Clump Distance to the Magellanic Clouds and Anomalous Colors in the Galactic Bulge

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现代科技拉进了人与人之间的距离的英语作文

现代科技拉进了人与人之间的距离的英语作文Modern technology has undoubtedly brought about numerous advancements that have transformed the way we live our lives. However, one concerning aspect of these technological developments is the growing distance between people. In the age of digital communication and social media, we find ourselves increasingly isolated from face-to-face interactions and genuine human connections.The rise of smartphones and instant messaging applications has revolutionized the way we communicate. Gone are the days when people would physically meet to catch up or have a meaningful conversation. Instead, we now rely on a constant stream of text messages, emojis, and short updates to stay connected with our friends and loved ones. While these tools may provide a sense of immediacy and convenience, they often lack the depth and emotional nuance that comes with in-person interactions.Moreover, the constant need to be connected to our devices has led to a phenomenon known as "phubbing," where individuals ignorethe people around them in favor of their phones. This behavior not only undermines the quality of our interpersonal relationships but also contributes to a growing sense of social isolation. Studies have shown that excessive screen time and digital engagement can lead to feelings of loneliness, depression, and anxiety, as we become increasingly disconnected from the physical world and the people in it.Another significant impact of modern technology on human relationships is the prevalence of social media. While platforms like Facebook, Instagram, and Twitter were initially designed to bring people together, they have often had the opposite effect. Instead of fostering genuine connections, these platforms have created a curated and often idealized version of our lives, leading to a sense of comparison and envy among users. This can lead to feelings of inadequacy and a disconnect from the authentic experiences of our peers.Furthermore, the anonymity and lack of face-to-face interaction on social media can encourage people to engage in cyberbullying, trolling, and other forms of online harassment. This can have devastating consequences on the mental health and well-being of individuals, particularly vulnerable populations such as teenagers and young adults.In addition to the impact on interpersonal relationships, modern technology has also influenced the way we approach romantic relationships. The rise of dating apps and online dating platforms has transformed the way we meet and interact with potential partners. While these tools can provide a convenient way to connect with a larger pool of potential matches, they can also contribute to a more superficial and transactional approach to relationships. The ease of swiping and the abundance of options can lead to a "fear of missing out" mentality, where individuals are constantly seeking the next best thing, rather than investing in meaningful connections.Moreover, the reliance on digital communication in romantic relationships can also lead to misunderstandings and a lack of emotional intimacy. Without the nonverbal cues and physical presence that come with in-person interactions, it can be challenging to convey the depth of our feelings and emotions effectively.Despite these challenges, it is important to recognize that modern technology is not inherently negative. When used in moderation and with intention, these tools can actually enhance our ability to stay connected with loved ones, access information, and explore new opportunities. The key is to find a balance between digital engagement and face-to-face interactions, and to prioritize the cultivation of meaningful relationships and genuine human connections.One potential solution to the growing distance between people in the digital age is to encourage more intentional and mindful use of technology. This could involve setting boundaries around screen time, actively engaging in offline activities and social events, and prioritizing quality time with loved ones. Additionally, educational initiatives and public awareness campaigns could help to raise awareness about the importance of maintaining a healthy balance between digital and physical interactions.Furthermore, the development of more socially conscious and community-oriented technology could also play a role in bridging the gap. For example, some social media platforms are exploring ways to foster more meaningful connections and facilitate in-person meetups and events. Similarly, advancements in virtual and augmented reality technologies could potentially create new avenues for more immersive and engaging forms of digital interaction.In conclusion, the impact of modern technology on human relationships is a complex and multifaceted issue. While these advancements have undoubtedly brought about many benefits, they have also contributed to a growing sense of distance and isolation between people. By recognizing the importance of maintaining a healthy balance between digital and physical interactions, and by exploring innovative solutions to foster more meaningfulconnections, we can work towards a future where technology enhances, rather than hinders, our ability to connect with one another.。

鲸鱼的歌唱：深海的回声英语作文

The Singing of Whales:Echoes of the Deep SeaWhales,the majestic creatures of the ocean,are known for their enchanting songs that resonate through the deep sea.Their melodic and complex vocalizations have captivated scientists and enthusiasts alike, sparking curiosity about the purpose and significance of their songs. Here are some reasons why the singing of whales is considered a fascinating phenomenon:Communication and Social Bonds:Whales use their songs as a means of communication within their social groups.These songs are often sung by male whales during the mating season to attract females and establish dominance.They serve as a way for whales to communicate their presence,location,and reproductive readiness.The intricate patterns and variations in their songs suggest a sophisticated form of communication.Cultural Transmission:Whales exhibit cultural behaviors,including their songs,which are passed down from generation to generation within their populations.Each population of whales has its unique song patterns,which can evolve and change over time.This cultural transmission of songs highlights the social learning and intelligence of whales.Long-Distance Communication:Whales'songs can travel vast distances through the ocean,thanks to the unique acoustic properties of water. These low-frequency sounds can travel for hundreds of miles,allowing whales to communicate with individuals in distant locations.The ability to communicate over long distances is crucial for maintaining social bonds,locating food sources,and navigating the vast ocean.Complex Song Structures:Whale songs are incredibly complex, consisting of a series of repeated phrases and themes.These songs can last for hours and contain a wide range of vocalizations,including clicks, whistles,and melodic patterns.The complexity of their songs suggests alevel of intelligence and cognitive abilities beyond what was previously understood.Emotional Expression:Whales'songs are believed to convey emotions and express individual identities.The melodic and haunting nature of their songs evokes a sense of beauty and mystery.Researchers have observed changes in the pitch,rhythm,and intensity of whale songs, suggesting that they may reflect the emotional state or intentions of the singing whale.Scientific Research and Conservation:Studying whale songs provides valuable insights into the behavior,population dynamics,and migration patterns of these magnificent creatures.Scientists use acoustic monitoring to track and analyze whale songs,contributing to our understanding of their complex social structures and the health of their populations.Conservation efforts aim to protect whales and their habitats,ensuring the continuation of their mesmerizing songs.In conclusion,the singing of whales is a captivating and mysterious phenomenon that serves as a form of communication,social bonding, and cultural transmission within their populations.Their complex and melodic songs travel through the deep sea,carrying echoes of their presence and emotions.Understanding and appreciating the significance of whale songs is crucial for their conservation and the preservation of the enchanting marine ecosystems they inhabit.。

方圆不独行,携手抵妙境作文

方圆不独行,携手抵妙境作文英文回答：Collaboration is a powerful tool that allows us to achieve incredible feats. When we work together, we can overcome challenges and reach new heights. This is especially true when it comes to exploring the unknown and venturing into uncharted territories. By joining forces, we can navigate the complexities of the world and discover the wonders that lie beyond.For example, imagine a group of scientists from different countries coming together to study the depths of the ocean. Each scientist brings their unique expertise and perspective, contributing to a collective understanding of the underwater world. Through their collaboration, they are able to uncover new species, understand marine ecosystems, and make groundbreaking discoveries.Collaboration not only enhances our knowledge andunderstanding, but it also fosters innovation. When diverse minds come together, they bring with them a wealth of ideas and perspectives. This diversity of thought sparkscreativity and leads to the development of new solutionsand technologies. By working together, we can tackle complex problems and find innovative ways to address them.Furthermore, collaboration promotes mutual support and growth. When we collaborate, we create a supportive environment where individuals can learn from one anotherand grow together. We can share our strengths and weaknesses, and help each other overcome obstacles. This sense of camaraderie and support fosters personal and professional growth, enabling us to become better versionsof ourselves.中文回答：合作是一种强大的工具，使我们能够实现令人难以置信的壮举。

海天奇观的名词解释英文

海天奇观的名词解释英文在这个广袤而神秘的地球上，自然界无处不在展现着令人叹为观止的景象。

其中，海洋和天空的交汇处，即海天奇观，以其壮美和神秘感而备受人们的关注。

下面，我们将对海天奇观的名词解释进行英文介绍。

1. 英文名词：Oceanic Aerial Phenomenon解释：Oceanic指的是海洋的，Aerial指的是与天空有关的，Phenomenon表示现象。

因此，Oceanic Aerial Phenomenon可以被理解为海洋和天空交汇处的奇观现象。

2. 英文名词：Marine Celestial Spectacle解释：Marine表示海洋的，Celestial表示天空的，Spectacle表示壮观的景象。

因此，Marine Celestial Spectacle可以被理解为海洋和天空交汇处的壮观景象。

3. 英文名词：Aqua-Cosmos Wonder解释：Aqua表示水的，Cosmos表示宇宙的，Wonder表示奇迹。

因此，Aqua-Cosmos Wonder可以被理解为水与宇宙交融处的奇迹。

4. 英文名词：Mystical Seasky Enigma解释：Mystical表示神秘的，Seasky表示海洋和天空，Enigma表示谜。

因此，Mystical Seasky Enigma可以被理解为神秘的海洋和天空之谜。

5. 英文名词：Oceanic Firmament Mirage解释：Oceanic表示海洋的，Firmament表示天空，Mirage表示幻象。

因此，Oceanic Firmament Mirage可以被理解为海洋与天空之间的幻象。

海天奇观是大自然中一种令人震撼和惊叹的现象，它们的出现常常超越了人类的想象力。

海洋在图景的边缘与蔚蓝的天空融为一体，创造出了一系列美丽而复杂的景观。

这些景象通常是由自然因素，如大气层和海洋的物理现象互相作用产生的。

例如，当太阳和海洋交织时，光线会发生折射和散射，形成令人惊叹的日落和日出景色。

知识的岛屿越大,无知的海岸线就越长英语作文

全文分为作者个人简介和正文两个部分：作者个人简介：Hello everyone, I am an author dedicated to creating and sharing high-quality document templates. In this era of information overload, accurate and efficient communication has become especially important. I firmly believe that good communication can build bridges between people, playing an indispensable role in academia, career, and daily life. Therefore, I decided to invest my knowledge and skills into creating valuable documents to help people find inspiration and direction when needed.正文：知识的岛屿越大,无知的海岸线就越长英语作文全文共3篇示例，供读者参考篇1The Larger the Island of Knowledge, the Longer the Shoreline of IgnoranceAs students, we are constantly in pursuit of knowledge, striving to expand the boundaries of our understanding andunravel the mysteries that surround us. However, the more we learn, the more we realize how vast the ocean of ignorance truly is. This paradoxical relationship between knowledge and ignorance is aptly captured in the phrase, "The larger the island of knowledge, the longer the shoreline of ignorance."At the outset of our academic journey, we are like explorers venturing into uncharted territories, armed with a sense of curiosity and a thirst for discovery. The world around us is a tapestry of unanswered questions, and each new piece of information we acquire is akin to a small pebble added to the island of our knowledge. With every lesson learned, every concept mastered, and every theory grasped, we feel a sense of accomplishment, as if we have conquered a new frontier.Yet, as our island of knowledge grows, so too does our awareness of the vast expanse of ignorance that surrounds it. With each new discovery, we uncover a multitude of new questions, each one beckoning us to explore further. It is as if the shoreline of our island extends infinitely, revealing new horizons of inquiry and inviting us to venture into the depths of the unknown.This realization can be both exhilarating and humbling. On one hand, it ignites within us a passionate desire to push theboundaries of our understanding, to dive into the depths of unexplored realms, and to contribute to the ever-expanding body of human knowledge. We are driven by an insatiable curiosity, a hunger for intellectual stimulation, and a desire to make our mark on the world through our discoveries and insights.On the other hand, the vastness of our ignorance can be daunting, reminding us of the limitations of our finite minds and the sheer immensity of the universe we inhabit. We are confronted with the sobering truth that no matter how much we learn, there will always be more to uncover, more mysteries to solve, and more questions to ponder.This dichotomy between knowledge and ignorance is not a cause for despair, but rather a testament to the beauty and complexity of the world we inhabit. It is a reminder that learning is a lifelong journey, one that demands humility, perseverance, and an unwavering commitment to intellectual growth.As students, we must embrace this paradox and allow it to fuel our quest for understanding. We must approach each new lesson with an open mind, recognizing that what we learn today may be challenged or refined by the discoveries of tomorrow. We must cultivate a spirit of intellectual curiosity, always seekingto probe deeper, to question assumptions, and to explore alternative perspectives.Furthermore, we must celebrate the collective nature of human knowledge, recognizing that no individual can possibly possess all the answers. We stand on the shoulders of giants, building upon the foundations laid by countless scholars, scientists, and thinkers who have come before us. It is through collaboration, cross-pollination of ideas, and the sharing of discoveries that we can truly push the boundaries of our understanding.The journey of knowledge is one that is never truly complete, for with each answer we uncover, a multitude of new questions emerge. Yet, it is this very journey that makes the pursuit of learning so exhilarating and fulfilling. As students, we have the privilege and responsibility to embrace this paradox, to revel in the joys of discovery while humbly acknowledging the vast oceans of ignorance that surround us.So let us dive into the depths of our curiosity, let us explore the uncharted territories of knowledge, and let us embrace the ever-expanding shoreline of ignorance. For it is in this endless cycle of learning and questioning that we find the true essenceof intellectual growth and the profound beauty of the human experience.篇2The Bigger the Island of Knowledge, the Longer the Shoreline of IgnoranceEver since I was a little kid, I've been fascinated by the vast unknown. Looking up at the night sky, I was in awe of the twinkling stars and the mysteries they held. As I grew older and began learning more in school, my childlike wonder evolved into an intellectual curiosity about the depths of human knowledge. It was in one of my philosophy classes that I first encountered the profound metaphor: "The bigger the island of knowledge, the longer the shoreline of ignorance." This idea resonated deeply with me and has continued to shape my perspective on learning and the pursuit of understanding.On the surface, the metaphor seems almost paradoxical. How can gaining more knowledge lead to increased ignorance? The answer lies in the nature of discovery itself. As we expand the boundaries of what is known, we invariably encounter new frontiers of the unknown. Much like an island's shoreline grows longer as its land mass increases, our awareness of the vastoceans of ignorance surrounding us expands in tandem with our acquisitions of knowledge.When I was a young student, my world of knowledge felt like a small, isolated island. The subjects I studied in elementary school – basic math, reading, writing, and science – were confined and well-defined. I could see the limits of my understanding, the shorelines were clear and close. However, as I progressed through my education, venturing into more advanced topics and specialized fields, the island grew. I learned about ancient civilizations, complex mathematical theories, intricate biological processes, and profound philosophical concepts. With each new discovery, novel fields of inquiry unveiled themselves, and the shorelines stretched further into the distance.It's a humbling realization that no matter how much we learn, there will always be an endless expanse of ignorance surrounding us. The more we know, the more we become aware of how much we don't know. This is not a cause for despair, however, but rather a testament to the boundless potential for growth and exploration that lies before us.One of the most exhilarating aspects of this metaphor is the implication that our journey of learning is never-ending. As wetraverse the shorelines of our current knowledge, venturing into the uncharted waters of ignorance, we inevitably discover new islands, new realms of understanding to explore and incorporate into our ever-expanding archipelago of knowledge.This process is not limited to the realm of academia or scientific endeavors; it permeates all facets of human experience. Every time we encounter a new culture, engage with a different perspective, or confront a complex challenge, we are presented with opportunities to expand our islands of knowledge and, consequently, reveal new shorelines of ignorance.The metaphor also serves as a potent reminder to approach knowledge with humility and an open mind. It would be folly to assume that our current understanding, no matter how vast, encompasses the entirety of truth or reality. There will always be aspects of the world, the universe, and the human experience that elude our comprehension, at least for the time being.As students, we must embrace this concept wholeheartedly. It is a call to maintain a sense of wonder, curiosity, and a thirst for learning that extends beyond the confines of our current curriculums or fields of study. We must be willing to question assumptions, challenge established paradigms, and venture intouncharted intellectual territories, for it is in those unexplored regions that the greatest discoveries and insights await.Furthermore, this metaphor encourages us to cultivate a sense of intellectual humility and respect for the perspectives and knowledge of others. Just as our individual islands of knowledge are surrounded by vast oceans of ignorance, so too are the collective islands of human understanding dwarfed by the enormity of the unknown. By recognizing the inherent limitations of our individual perspectives and embracing the diversity of knowledge and experiences that others bring to the table, we can collectively navigate the shorelines of ignorance more effectively.In practical terms, this metaphor can serve as a guiding principle for our approach to learning and problem-solving. When confronted with a complex issue or a gap in our understanding, we should not shy away from the discomfort of ignorance. Instead, we should embrace it as an opportunity to expand our knowledge, to venture beyond the familiar shorelines and explore the uncharted waters that lie beyond.This mindset fosters a culture of intellectual curiosity, critical thinking, and a willingness to challenge preconceived notions. It encourages us to ask probing questions, seek out diverseperspectives, and engage in respectful discourse and debate. By doing so, we not only expand our individual islands of knowledge but also contribute to the collective growth of human understanding.Ultimately, the metaphor of "the bigger the island of knowledge, the longer the shoreline of ignorance" is a profound and empowering concept that should shape our approach to learning and intellectual growth. It reminds us to embrace the vastness of the unknown with humility, curiosity, and a relentless pursuit of understanding. It challenges us to venture beyond the familiar shores, to explore new frontiers of knowledge, and to contribute to the collective expansion of human understanding.As students, we stand at the precipice of a boundless ocean of ignorance, with the opportunity to chart new intellectual territories and discover uncharted islands of knowledge. Let us embrace this metaphor as a guiding principle, a call to lifelong learning and intellectual exploration, and a testament to the endless potential that lies within the human spirit.篇3The Island of Knowledge and the Shoreline of IgnoranceAs a student, I often feel like I'm on a constant journey of exploration, sailing across vast seas of information in search of knowledge. Each new subject I delve into is like an uncharted island waiting to be discovered and understood. But as I've learned more and more, a peculiar pattern has emerged – the more I know, the more I realize how much I don't know. It's as if the island of my knowledge is surrounded by an ever-expanding shoreline of ignorance.When I was younger, the world seemed so simple. The islands of knowledge felt tiny and isolated, surrounded by seemingly endless oceans of the unknown. I remember learning basic facts about animals, planets, and historical events, feeling like I had a pretty good grasp on how everything worked. But as I grew older and my education progressed, those once-tiny islands began to merge and expand, revealing just how vast the realm of human understanding truly is.Take science, for instance. In primary school, science was a straightforward affair – we learned about the basic states of matter, the planets in our solar system, and perhaps did a few simple experiments with vinegar and baking soda. At that point, the "island" of scientific knowledge felt relatively small andself-contained. But as I advanced through secondary school andinto university-level coursework, that modest islet rapidly transformed into a sprawling archipelago of interconnected disciplines.Suddenly, I found myself grappling with complex concepts like quantum mechanics, evolutionary biology, and biochemistry. The more I studied, the more I realized how little I truly understood about the intricate workings of the universe. Each new discovery seemed to uncover a dozen more unanswered questions, like an ever-expanding fractal pattern of uncertainty.And it's not just the sciences that exemplify this phenomenon. The same principle holds true across all academic domains. In literature, for instance, I might have started with simple children's books and fables, only to eventually encounter the rich tapestries of symbolism and metaphor woven into the great novels and poems of human history. The island of literary knowledge, which once felt so simple and straightforward, revealed layers upon layers of nuance and interpretation the deeper I ventured.The truth is, the more we learn, the more we're forced to confront the boundaries of our understanding. With each new piece of knowledge we acquire, we're effectively redrawing the maps of what we know and don't know. The islands ofcomprehension may grow larger and more interconnected, but their sprawling shorelines only serve to highlight the vast, unexplored waters that still lie beyond.This realization can be both humbling and deeply motivating. On one hand, it's a stark reminder of the limitations of human intellect and the sheer scale of all that remains to be discovered. No matter how much we study and learn, there will always be more questions than answers, more mysteries to unravel.But at the same time, this ever-expanding shoreline of ignorance is what drives the relentless pursuit of knowledge forward. It's what inspires scientists to scour the depths of the oceans and the farthest reaches of the cosmos for new insights. It's what compels philosophers and thinkers to continually reexamine and refine the foundations of human understanding. The unknown isn't a barrier – it's an invitation to explore, to sail forth into uncharted waters and claim new lands of comprehension.As a student, this perspective has been invaluable in shaping my approach to learning. I've come to understand that true wisdom isn't about accumulating facts and figures, but about cultivating a deep sense of humility and curiosity. It's about recognizing that the more we know, the more we realize howlittle we truly understand about the complexities of the world around us.So while the island of my knowledge may continue to grow and evolve, I've learned to embrace the ever-lengthening shoreline of ignorance that surrounds it. For it is in those vast, unexplored waters that the greatest opportunities for discovery and growth lie. Each unanswered question is a siren call, beckoning me to set sail once more in search of new lands to claim, new horizons to conquer.The journey of learning is an endless one, with no final destination in sight. But that's precisely what makes it so exhilarating and rewarding. As long as the shoreline of ignorance continues to stretch out before us, there will always be new frontiers to explore, new mysteries to unravel, and new islands of knowledge to claim as our own.。

原始森林探险队作文英语

Embarking on an adventure into the heart of a pristine forest is an experience that few can truly fathom.The thrill of exploring untouched nature,the sounds of wildlife echoing through the trees,and the sense of being one with the environment is both humbling and exhilarating.Setting the Scene:The journey begins with a team of intrepid explorers,each with their own set of skills and expertise.They gather their gear,ensuring they have the necessary equipment for survival in the wild:tents,sleeping bags,compasses,maps,and first aid kits.The team is composed of a seasoned leader,a botanist to identify flora,a zoologist to study the fauna, and a survival expert to guide them through the challenges they may face.The Trek Begins:As the team ventures deeper into the forest,the air becomes denser,filled with the scent of damp earth and the hum of insects.The sunlight filters through the canopy above, casting a dappled pattern on the forest floor.The path is not clearly marked,and the team must rely on their navigational skills and the guidance of the forest itself to find their way.Encountering the Wildlife:The zoologist in the group is particularly excited as they come across various species of birds and mammals,some of which are rare and endangered.The team observes from a distance,taking notes and photographs to document their findings.They are careful not to disturb the animals or their habitats,respecting the delicate balance of the ecosystem. Overcoming Obstacles:The path is not without its challenges.The team encounters dense thickets,steep inclines, and even a swiftflowing river that they must cross.The survival expert leads the group in constructing a makeshift bridge,demonstrating the importance of teamwork and resourcefulness.Camping in the Wilderness:As night falls,the team sets up camp.The botanist identifies edible plants and berries, contributing to their meal for the evening.The sounds of the forest at night are a symphony of hoots,howls,and rustling leaves,adding an air of mystery to their surroundings.Discovering the Unseen:During their exploration,the team stumbles upon a hidden waterfall,a sight that takes their breath away.The water cascades down the rocks,creating a serene and refreshing environment.This discovery is a testament to the beauty and surprises that the forestholds.Reflecting on the Journey:As the expedition comes to an end,the team reflects on the lessons learned and the memories made.They have not only gained knowledge about the forest and its inhabitants but also about themselves and their ability to adapt and overcome challenges. The Return:Emerging from the forest,the team is greeted by the familiar sights and sounds of civilization.However,the experience of the原始forest has left an indelible mark on their hearts,inspiring a deeper appreciation for the natural world and the importance of conservation.In conclusion,the adventure into the原始forest is not just a physical journey but a spiritual one as well.It is a reminder of the interconnectedness of all life and the need to preserve the habitats that sustain it.The teams experience serves as a narrative of courage, curiosity,and the profound impact that immersing oneself in nature can have on ones perspective of the world.。

The effects of dust in simple environments Large Magellanic Cloud HII regions

ERIC F. BELL, KARL D. GORDON, ROBERT C. KENNICUTT, JR., & DENNIS ZARITSKY Steward Observatory, University of Arizona, Tucson, AZ 85721
TO APPEAR IN APJ: January 20 2002, vol. 565, no. 1
ies of different types, as a function of redshift, gives us direct in-
sight into where, when and how galaxies evolve (see e.g. Madau
et al. 1996; Blain et al. 1999; Steidel et al.ቤተ መጻሕፍቲ ባይዱ1999, for attempts to
ABSTRACT
We investigate the effects of dust on Large Magellanic Cloud (LMC) H II region spectral energy distributions using arcminute-resolution far-ultraviolet (FUV), Hα, far-infrared (FIR), and radio images. Widely-used indicators of the amount of light lost to dust (attenuation) at Hα and in the FUV correlate with each other, although often with substantial scatter. There are two interesting systematic discrepancies. First, Hα attenuations estimated from the Balmer decrement are lower than those estimated from the Hα-to-thermal radio luminosity ratio. Our data, at this stage, cannot unambiguously identify the source of this discrepancy. Second, the attenuation at 1500Å and UV spectral slope, β, correlate, although the slope and scatter are substantially different from the correlation ﬁrst derived for starbursting galaxies by Calzetti et al. Combining our result with those of Meurer et al. for ultra-luminous infrared galaxies and Calzetti et al. for starbursting galaxies, we conclude that no single relation between β and 1500Å attenuation is applicable to all star-forming systems.

科技拉远了人与人之间的距离作文英语

科技拉远了人与人之间的距离作文英语Technology has undoubtedly brought about significant changes in the way we live our lives. It has revolutionized the way we communicate, work, and interact with one another. However, with these advancements, there is a growing concern that technology has also contributed to a sense of isolation and distance between people.In the past, human interaction was primarily face-to-face. People would gather in physical spaces, engage in conversations, and form meaningful connections. The advent of technology, particularly the internet and social media, has transformed the way we communicate. We can now connect with people across the globe with just a few taps on our smartphones. While this has undoubtedly made it easier to stay in touch with loved ones and maintain long-distance relationships, it has also led to a shift in the quality and depth of our interactions.One of the most significant ways in which technology has impacted human relationships is the way we communicate. Instead of engaging in face-to-face conversations, we often rely on text messages, emails, and social media posts to convey our thoughts and feelings. While these methods can be convenient and efficient,they lack the personal touch and nonverbal cues that are essential for building and maintaining meaningful relationships. Without the ability to read body language, tone of voice, and facial expressions, it becomes increasingly difficult to truly understand and empathize with one another.Moreover, the constant bombardment of information and notifications from our digital devices can be overwhelming and distracting. We find ourselves constantly checking our phones, scrolling through social media, and engaging in multiple conversations simultaneously. This fragmentation of our attention can make it challenging to be fully present and engaged in the moment, which is crucial for fostering deep connections with others.Another concern is the way technology has influenced our social behavior. Many people, particularly younger generations, have become accustomed to communicating through screens rather than face-to-face interactions. This can lead to a lack of social skills and difficulty in navigating real-world social situations. As a result, some individuals may struggle to form and maintain meaningful relationships, leading to feelings of loneliness and isolation.Furthermore, the anonymity and lack of accountability that often come with online interactions can encourage people to behave in ways they might not in a face-to-face setting. This can lead to thespread of misinformation, cyberbullying, and a general lack of empathy and understanding between individuals.It is important to recognize that technology is not inherently good or bad. It is a tool that can be used to enhance our lives and strengthen our connections with others. However, it is crucial that we learn to strike a balance and use technology in a way that complements and enhances our human interactions, rather than replacing them entirely.One way to achieve this balance is to be mindful of our technology use and make a conscious effort to prioritize face-to-face interactions. This could involve setting aside dedicated time for family and friends, engaging in hobbies and activities that bring us together in physical spaces, and being present and attentive during conversations.Additionally, we can use technology in a way that fosters deeper connections. For example, video calls can allow us to see and hear each other, creating a more personal and engaging experience than a simple text message. Social media can also be used to share meaningful experiences and connect with like-minded individuals, rather than just scrolling and consuming content.Ultimately, the challenge lies in finding a way to integrate technology into our lives in a way that enhances our human connections, ratherthan isolating us from one another. By being mindful of our technology use and prioritizing face-to-face interactions, we can work towards maintaining and strengthening the meaningful relationships that are so essential to our well-being and happiness.。

宇宙光速之旅英语作文400字左右

宇宙光速之旅英语作文400字左右Venturing into the uncharted territories of the cosmos, the concept of interstellar travel has long captivated the imaginations of scientists, engineers, and dreamers alike. Among the formidable challenges posed by this ambitious endeavor, the fundamental limitation of the speed of light stands as a formidable obstacle.The speed of light, denoted by the constant "c," is an immutable law of nature. In a vacuum, it propagates at an astonishing velocity of approximately 299,792,458 meters per second. This extraordinary speed, while enabling the transmission of information and energy across vast distances, also imposes inherent constraints oninterstellar travel.To traverse the interstellar void between stars and galaxies, spacecraft would require propulsion systems capable of propelling them at relativistic speeds, approaching a significant fraction of the speed of light.However, as a spacecraft approaches these relativistic velocities, several fundamental challenges arise.Firstly, the time dilation effect of special relativity becomes increasingly pronounced. As a spacecraft approaches the speed of light, time slows down relative to an observer at rest. This means that the crew of a relativistic spacecraft would experience time at a slower rate than those on Earth. For example, a hypothetical spacecraft traveling at 90% of the speed of light for one year would return to Earth after only two years, as measured by the Earth's clocks, while the crew on board would have experienced approximately two and a half years.Another significant challenge is the relativistic increase in mass. As a spacecraft approaches the speed of light, its mass increases exponentially. This means that the amount of energy required to accelerate a spacecraft to relativistic speeds becomes prohibitively large. Conventional rocket propulsion, based on the principle of action and reaction, would be inadequate for interstellar travel due to the exponential increase in energyrequirements.Furthermore, the interstellar medium is far from being a perfect vacuum. It contains various particles, including interstellar dust and gas. Collisions with these particles at relativistic speeds could generate enormous heat and radiation, posing significant hazards to the crew and spacecraft. Adequate shielding and protection measures would be essential to mitigate these risks.Despite these formidable challenges, the pursuit of interstellar travel continues to inspire scientific research and technological innovation. Scientists and engineers are exploring various theoretical and experimental approaches to overcome the limitations imposed by the speed of light. These include concepts such as warp drives, which propose the manipulation of spacetime to create a "bubble" around the spacecraft, allowing it to travel faster than the speed of light without violating the laws of physics.Additionally, the development of advanced propulsionsystems, such as ion propulsion and nuclear fusion propulsion, offers potential solutions for achieving relativistic speeds. These propulsion systems couldgenerate continuous thrust over extended periods, enabling spacecraft to accelerate gradually and reach relativistic velocities without encountering the same exponential energy requirements as conventional rocket propulsion.While the challenges of interstellar travel are immense, they are not insurmountable. Through continued scientific research, technological advancements, and unwavering determination, humanity may one day venture beyond the confines of our solar system and embark on extraordinary journeys to distant stars and galaxies.。

英译汉。高英

Lesson 11)The one I am thinking of particularly is entered by Gothicarched gateway of aged brick and stone .You pass from the heat and glare of a big, open square into a cool, dark cavern which extends as far as the eye can see, losing itself in the shadowy distance.此时此刻我要说的集市的入口是一座古老的砖石结构的哥特式拱门，年代非常久远。

当你穿过一个烈日暴晒的大型露天广场，然后走进一个凉爽、幽暗的洞穴。

这洞穴一直一直向前延伸，一眼望不到尽头，最终消失在远处的阴影里。

2)It is a point of honor with the customers not to let the shopkeeper guess what it is she really likes and want until the last moment. 对于顾客来说，至关重要的一点是，不到最后一刻是不能让店主猜到她心里究竟中意哪样东西、想买哪样东西的.3)The seller ,on the other hand ,makes a point of protesting that the price he is charging is depriving him of all profit, and that he is sacrificing this because of his personal regard for the customer. 而在店主那一方来说，则是竭尽全力的让顾客相信，他开出的价钱使他根本无利可图，而他之所以愿意这样做完全是出于本人对顾客的敬重。

剑桥雅思阅读4原文翻译及答案解析（test3）

剑桥雅思阅读4原文翻译及答案解析(test3)为了帮助大家更好地备考雅思阅读，下面小编给大家分享剑桥雅思阅读4原文翻译及答案解析(test3)，希望对你们有用。

剑桥雅思阅读4原文(test3)READING PASSAGE 1You should spend about 20 minutes on Questions 1-13 which are based on Reading Passage 1 below.Micro-Enterprise Credit for Street Youth‘I am from a large, poor family and for many years we have done without breakfast. Ever since I joined the Street Kids International program I have been able to buy my family sugar and buns for breakfast. I have also bought myself decent second-hand clothes and shoes.’Doreen Soko‘We’ve had business experience. Now I’m confident to expand what we’ve been doing. I’ve learnt cash management, and the way of keeping money so we save for re-investment. Now business is a part of our lives. As well, we didn’t know each other before —now we’ve made new friends.’Fan KaomaParticipants in the Youth Skills Enterprise Initiative Program, ZambiaIntroductionAlthough small-scale business training and credit programs have become more common throughout the world, relatively little attention has been paid to the need to direct such opportunities to young people. Even less attention has been paid to children living on the street or in difficult circumstances.Over the past nine years, Street Kids International (S.K.I.) hasbeen working with partner organisations in Africa, Latin America and India to support the economic lives of street children. The purpose of this paper is to share some of the lessons S.K.I. and our partners have learned.BackgroundTypically, children do not end up on the streets due to a single cause, but to a combination of factors: a dearth of adequately funded schools, the demand for income at home, family breakdown and violence. The street may be attractive to children as a place to find adventurous play and money. However, it is also a place where some children are exposed, with little or no protection, to exploitative employment, urban crime, and abuse.Children who work on the streets are generally involved in unskilled, labour-intensive tasks which require long hours, such as shining shoes, carrying goods, guarding or washing cars, and informal trading. Some may also earn income through begging, or through theft and other illegal activities. At the same time, there are street children who take pride in supporting themselves and their families and who often enjoy their work. Many children may choose entrepreneurship because it allows them a degree of independence, is less exploitative than many forms of paid employment, and is flexible enough to allow them to participate in other activities such as education and domestic tasks.Street Business PartnershipsS.K.I. has worked with partner organisations in Latin America, Africa and India to develop innovative opportunities for street children to earn income.The S.K.I. Bicycle Courier Service first started in the Sudan. Participants in this enterprise were supplied with bicycles, whichthey used to deliver parcels and messages, and which they were required to pay for gradually from their wages. A similar program was taken up in Bangalore, India.Another successful project, The Shoe Shine Collective, was a partnership program with the Y.W.C.A. in the Dominican Republic. In this project, participants were lent money to purchase shoe shine boxes. They were also given a safe place to store their equipment, and facilities for individual savings plans.The Youth Skills Enterprise Initiative in Zambia is a joint program with the Red Cross Society and the Y.W.C.A. Street youths are supported to start their own small business through business training, life skills training and access to credit.Lessons learnedThe following lessons have emerged from the programs that S.K.I. and partner organisations have created.Being an entrepreneur is not for everyone, nor for every street child. Ideally, potential participants will have been involved in the organisation’s programs for at least six months, and trust and relationship-building will have already been established.The involvement of the participants has been essential to the development of relevant programs. When children have had a major role in determining procedures, they are more likely to abide by and enforce them.It is critical for all loans to be linked to training programs that include the development of basic business and life skills.There are tremendous advantages to involving parents or guardians in the program, where such relationships exist. Home visits allow staff the opportunity to know where the participants live, and to understand more about each individual’s situation.Small loans are provided initially for purchasing fixed assetssuch as bicycles, shoe shine kits and basic building materials for a market stall. As the entrepreneurs gain experience, the enterprises can be gradually expanded and consideration can be given to increasing loan amounts. The loan amounts in S.K.I. programs have generally ranged from US$30-$100.All S.K.I. programs have charged interest on the loans, primarily to get the entrepreneurs used to the concept of paying interest on borrowed money. Generally the rates have been modest (lower than bank rates).ConclusionThere is a need to recognise the importance of access to credit for impoverished young people seeking to fulfil economic needs. The provision of small loans to support the entrepreneurial dreams and ambitions of youth can be an effective means to help them change their lives. However, we believe that credit must be extended in association with other types of support that help participants develop critical life skills as well as productive businesses.Questions 1-4Choose the correct letter, A, B, C or D.Write your answers in boxes 1-4 on your answer sheet.1 The quotations in the box at the beginning of the articleA exemplify the effects of S.K.I.B explain why S.K.I. was set up.C outline the problems of street children.D highlight the benefits to society of S.K.I.2 The main purpose of S.K.I. is toA draw the attention of governments to the problem of street children.B provide school and social support for street children.C encourage the public to give money to street children.D give business training and loans to street children.3 Which of the following is mentioned by the writer as a reason why children end up living on the streets?A unemploymentB warC povertyD crime4 In order to become more independent, street children mayA reject paid employment.B leave their families.C set up their own businesses.D employ other children.Questions 5-8Complete the table below.Choose NO MORE THAN THREE WORDS from Reading Passage 1 for each answer.Write your answers in boxes 5-8 on your answer sheet.Country Organisations Involved Type of Project Support Provided5………………and………………S.K.I courier service ? provision of 6………………………Dominican Republic ? S.K.IY.W.C.A 7………………… ? loansstorage facilitiessavings plansZambia ? S.K.I.The Red CrossY.W.C.A. setting up small businesses ? business training8…………trainingaccess to creditQuestions 9-12Do the following statements agree with the claims of the writer in Reading Passage 1?In boxes 9-12 on your answer sheet writeYES if the statement agrees with the claims of the wirterNO if the statement contradicts the claims of the writerNOT GIVEN if it is impossible to say what the writer thinks about this9 Any street child can set up their own small business if given enough support.10 In some cases, the families of street children may need financial support from S.K.I.11 Only one fixed loan should be given to each child.12 The children have to pay back slightly more money than they borrowed.Question 13Choose the correct letter, A, B, C or D.Write your answer in box 13 on your answer sheet.The writers conclude that money should only be lent to street childrenA as part of a wider program of aid.B for programs that are not too ambitious.C when programs are supported by local businesses.D if the projects planned are realistic and useful.READING PASSAGE 2You should spend about 20 minutes on Questions 14-26 which are based on Reading Passage 2 on the following pages.Questions 14-27Reading Passage 2 has four sections A-D.Choose the correct heading for each section from the list of headings below.Write the correct number i-vi in boxes 14-17 on your answer sheet.List of HeadingsI Causes of volcanic eruptionIi Efforts to predict volcanic eruptionIii Volcanoes and the features of our planetIv Different types of volcanic eruptionV International relief effortsVi The unpredictability of volcanic eruptions14 Section A15 Section B16 Section C17 Section DVolcanoes-earth-shattering newsWhen Mount Pinatubo suddenly erupted on 9 June 1991, the power of volcanoes past and present again hit the headlinesA Volcanoes are the ultimate earth-moving machinery. A violent eruption can blow the top few kilometres off a mountain, scatter fine ash practically all over the globe and hurl rock fragments into the stratosphere to darken the skies a continent away.But the classic eruption — cone-shaped mountain, big bang, mushroom cloud and surges of molten lava — is only a tiny part of a global story. Vulcanism, the name given to volcanic processes, really has shaped the world. Eruptions have rifted continents, raised mountain chains, constructed islands and shaped the topography of the earth. The entire ocean floor has abasement of volcanic basalt.Volcanoes have not only made the continents, they are also thought to have made the world’s first stable atmosphere and provided all the water for the oceans, rivers and ice-caps. There are now about 600 active volcanoes. Every year they add two or three cubic kilometres of rock to the continents. Imagine a similar number of volcanoes smoking away for the last 3,500 million years. That is enough rock to explain the continental crust.What comes out of volcanic craters is mostly gas. More than 90% of this gas is water vapour from the deep earth: enough to explain, over 3,500 million years, the water in the oceans. The rest of the gas is nitrogen, carbon dioxide, sulphur dioxide, methane, ammonia and hydrogen. The quantity of these gases, again multiplied over 3,500 million years, is enough to explain the mass of the world’s atmosphere. We are alive because volcanoes provided the soil, air and water we need.B Geologists consider the earth as having a molten core, surrounded by a semi-molten mantle and a brittle, outer skin. It helps to think of a soft-boiled egg with a runny yolk, a firm but squishy white and a hard shell. If the shell is even slightly cracked during boiling, the white material bubbles out and sets like a tiny mountain chain over the crack — like an archipelago of volcanic islands such as the Hawaiian Islands. But the earth is so much bigger and the mantle below is so much hotter.Even though the mantle rocks are kept solid by overlying pressure, they can still slowly ‘flow’ like thick treacle. The flow, thought to be in the form of convection currents, is powerful enough to fracture the ‘eggshell’ of the crust into plates, and keep them bumping and grinding against each other, or even overlapping, at the rate of a few centimetres a year. Thesefracture zones, where the collisions occur, are where earthquakes happen. And, very often, volcanoes.C These zones are lines of weakness, or hot spots. Every eruption is different, but put at its simplest, where there are weaknesses, rocks deep in the mantle, heated to 1,350℃, will start to expand and rise. As they do so, the pressure drops, and they expand and become liquid and rise more swiftly.Sometimes it is slow: vast bubbles of magma — molten rock from the mantle — inch towards the surface, cooling slowly, to show through as granite extrusions (as on Skye, or the Great Whin Sill, the lava dyke squeezed out like toothpaste that carries part of Hadrian’s Wall in no rthern England). Sometimes — as in Northern Ireland, Wales and the Karoo in South Africa —the magma rose faster, and then flowed out horizontally on to the surface in vast thick sheets. In the Deccan plateau in western India, there are more than two million cubic kilometres of lava, some of it 2,400 metres thick, formed over 500,000 years of slurping eruption.Sometimes the magma moves very swiftly indeed. It does not have time to cool as it surges upwards. The gases trapped inside the boiling rock expand suddenly, the lava glows with heat, it begins to froth, and it explodes with tremendous force. Then the slightly cooler lava following it begins to flow over the lip of the crater. It happens on Mars, it happened on the moon, it even happens on some of the moons of Jupiter and Uranus. By studying the evidence, vulcanologists can read the force of the great blasts of the past. Is the pumice light and full of holes? The explosion was tremendous. Are the rocks heavy, with huge crystalline basalt shapes, like t he Giant’s Causeway in Northern Ireland? It was a slow, gentle eruption.The biggest eruptions are deep on the mid-ocean floor, where new lava is forcing the continents apart and widening the Atlantic by perhaps five centimetres a year. Look at maps of volcanoes, earthquakes and island chains like the Philippines and Japan, and you can see the rough outlines of what are called tectonic plates —the plates which make up the earth’s crust and mantle. The most dramatic of these is the Pacific ‘ring of fire’ wh ere there have been the most violent explosions —Mount Pinatubo near Manila, Mount St Helen’s in the Rockies and El Chichón in Mexico about a decade ago, not to mention world-shaking blasts like Krakatoa in the Sunda Straits in 1883.D But volcanoes are not very predictable. That is because geological time is not like human time. During quiet periods, volcanoes cap themselves with their own lava by forming a powerful cone from the molten rocks slopping over the rim of the crater; later the lava cools slowly into a huge, hard, stable plug which blocks any further eruption until the pressure below becomes irresistible. In the case of Mount Pinatubo, this took 600 years.Then, sometimes, with only a small warning, the mountain blows its top. It did this at Mon t Pelée in Martinique at 7.49 a.m. on 8 May, 1902. Of a town of 28,000, only two people survived. In 1815, a sudden blast removed the top 1,280 metres of Mount Tambora in Indonesia. The eruption was so fierce that dust thrown into the stratosphere darkened the skies, cancelling the following summer in Europe and North America. Thousands starved as the harvests failed, after snow in June and frosts in August. Volcanoes are potentially world news, especially the quiet ones.Questions 18-21Answer the questions below using NO MORE THAN THREE WORDS AND/OR A NUMBER from the passage for each answer.Write your answers in boxes 18-21 on your answer sheet.18 What are the sections of the earth’s crust, often associated with volcanic activity, called?19 What is the name given to molten rock from the mantle?20 What is the earthquake zone on the Pacific Ocean called?21 For how many years did Mount Pinatubo remain inactive?Questions 22-26Complete the summary below.Choose NO MORE THAN TWO WORDS from the passage for each answer.Write your answers in boxes 22-26 on your answer sheet.Volcanic eruptions have shaped the earth’s land surface. They may also have produced the world’s atmosphere and 22…… . Eruptions occur when molten rocks from the earth’s mantle rise and expand. When they become liquid, they move quickly through cracks in the surface. There are different types of eruption. Sometimes the 23……. moves slowly and forms outcrops of granite on the earth’s surface. When it moves more quickly it may flow out in thick horizontal sheets. Examples of this type of eruption can be found in Northern Ireland, Wales, South Africa and 24…… . A third type of eruption occurs when the lava emerges very quickly and 25…… violently. This happens because the magma moves so suddenly that 26…… are emitted.READING PASSAGE 3You should spend about 20 minutes on Questions 27-40 which are based on Reading Passage 3 belowObtaining Linguistic DataA Many procedures are available for obtaining data about alanguage. They range from a carefully planned, intensive field investigation in a foreign country to a casual introspection about one’s mother tongue carried out in an armchair at home.B In all cases, someone has to act as a source of language data — an informant. Informants are (ideally) native speakers of a language, who provide utterances for analysis and other kinds of information about the language (e.g. translations, comments about correctness, or judgements on usage). Often, when studying their mother tongue, linguists act as their own informants, judging the ambiguity, acceptability, or other properties of utterances against their own intuitions. The convenience of this approach makes it widely used, and it is considered the norm in the generative approach to linguistics. But a lin guist’s personal judgements are often uncertain, or disagree with the judgements of other linguists, at which point recourse is needed to more objective methods of enquiry, using non-linguists as informants. The latter procedure is unavoidable when working on foreign languages, or child speech.C Many factors must be considered when selecting informants —whether one is working with single speakers (a common situation when languages have not been described before), two people interacting, small groups or large-scale samples. Age, sex, social background and other aspects of identity are important, as these factors are known to influence the kind of language used. The topic of conversation and the characteristics of the social setting (e.g. the level of formality) are also highly relevant, as are the personal qualities of the informants (e.g. their fluency and consistency). For larger studies, scrupulous attention has been paid to the sampling theory employed, and in all cases, decisions have to be made about thebest investigative techniques to use.D Today, researchers often tape-record informants. This enables the linguist’s claims about the language to be checked, and provides a way of making those claims more accurate (‘difficult’ pieces of speech can be li stened to repeatedly). But obtaining naturalistic, good-quality data is never easy. People talk abnormally when they know they are being recorded, and sound quality can be poor. A variety of tape-recording procedures have thus been devised to minimise the ‘observer’s paradox’ (how to observe the way people behave when they are not being observed). Some recordings are made without the speakers being aware of the fact — a procedure that obtains very natural data, though ethical objections must be anticipated. Alternatively, attempts can be made to make the speaker forget about the recording, such as keeping the tape recorder out of sight, or using radio microphones. A useful technique is to introduce a topic that quickly involves the speaker, and stimulates a natural language style (e.g. asking older informants about how times have changed in their locality).E An audio tape recording does not solve all the linguist’s problems, however. Speech is often unclear and ambiguous. Where possible, therefore, the recording has to be supplemented by the observer’s written comments on the non-verbal behaviour of the participants, and about the context in general.A facial expression, for example, can dramatically alter the meaning of what is said. Video recordings avoid these problems to a large extent, but even they have limitations (the camera cannot be everywhere), and transcriptions always benefit from any additional commentary provided by an observer.F Linguists also make great use of structured sessions, inwhich they systematically ask their informants for utterances that describe certain actions, objects or behaviours. With a bilingual informant, or through use of an interpreter, it is possible to use translation techniques (‘How do you say table in your language?’). A large number of points can be covered in a short time, using interview worksheets and questionnaires. Often, the researcher wishes to obtain information about just a single variable, in which case a restricted set of questions may be used: a particular feature of pronunciation, for example, can be elicited by asking the informant to say a restricted set of words. There are also several direct methods of elicitation, such as asking informants to fill in the blanks in a substitution frame (e.g. I___ see a car), or feeding them the wrong stimulus for correction (‘Is it possible to say I no can see?’).G A representative sample of language, compiled for the purpose of linguistic analysis, is known as a corpus. A corpus enables the linguist to make unbiased statements about frequency of usage, and it provides accessible data for the use of different researchers. Its range and size are variable. Some corpora attempt to cover the language as a whole, taking extracts from many kinds of text; others are extremely selective, providing a collection of material that deals only with a particular linguistic feature. The size of the corpus depends on practical factors, such as the time available to collect, process and store the data: it can take up to several hours to provide an accurate transcription of a few minutes of speech. Sometimes a small sample of data will be enough to decide a linguistic hypothesis; by contrast, corpora in major research projects can total millions of words. An important principle is that all corpora, whatever their size, are inevitably limited in their coverage, and always need to be supplementedby data derived from the intuitions of native speakers of the language, through either introspection or experimentation.Questions 27-31Reading Passage 3 has seven paragraphs labeled A-G.Which paragraph contains the following information?Write the correct letter A-G in boxes 27-31 on your answer sheet.NB You may use any letter more than once.27 the effect of recording on the way people talk28 the importance of taking notes on body language29 the fact that language is influenced by social situation30 how informants can be helped to be less self-conscious31 various methods that can be used to generate specific dataQuestions 32-36Complete the table below.Choose NO MORE THAN THREE WORDS from the passage for each answer.Write your answers in boxes 32-36 on your answer sheet.METHODS OF OBTAINING LINGUISTIC DATA ADVANTAGES DISADVANTAGES32……as informant convenient method of enquiry not objective enoughNon-linguist as informant necessary with 33…… and child speech the number of factors to be consideredRecording an informant allows linguists’ claims to be checked 34……of soundVideoing an informant allows speakers’ 35…… to be observed 36……might mi ss certain thingsQuestions 37-40Complete the summary of paragraph G below.Choose NO MORE THAN THREE WORDS from the passage for each answer.Write your answers in boxes 37-40 on your answer sheet.A linguist can use a corpus to comment objectively on 37…… . Some corpora include a wide range of language while others are used to focus on a 38…… . The length of time the process takes will affect the 39…… of the corpus. No corpus can ever cover the whole language and so linguists often find themselves relying on the additional information that can be gained from the 40…… of those who speak the language concerned.剑桥雅思阅读4原文参考译文(test3)Passage1参考译文Micro-Enterprise Credit for Street Youth流浪儿童的小型企业贷款‘I am from a large, poor family and for many years we have done without breakfast. Ever since I joined the Street Kids International program I have been able to buy my family sugar and buns for breakfast. I have also bought myself decent second-hand clothes and shoes.’Doreen Soko“我来自一个贫困的大家庭。

High-Velocity Clouds Related to the Magellanic System

a r X i v :a s t r o -p h /9909080v 2 8 M a r 2001HIGH-VELOCITY CLOUDS RELATED TO THE MAGELLANIC SYSTEMM.E.PUTMAN Center for Astrophysics and Space Astronomy,University of Colorado,Boulder CO,80309-0389,USA.1.Introduction The results of the interaction between the Milky Way and the Magellanic Clouds are revealed through several high velocity complexes which are con-nected to the Clouds.The exact mechanism of their formation is under some debate,but they remain the only group of high-velocity clouds (HVCs)for which we have an origin and roughly a distance.Given that,the Magellanic HVCs can be used as a calibrator for other HVCs,while also providing an opportunity to closely investigate the remnants of an interacting system.These HVCs may hold the key to the star formation history,kinematic structure,and present Hubble type of the Magellanic Clouds,and their proximity to the Milky Way allows us to estimate key Galactic parameters.The HVCs related to the Magellanic System can be classiﬁed into three major complexes:the Magellanic Bridge,an HI connection between the Clouds;the Magellanic Stream,which trails the clouds and is one of the largest HI features in the sky outside of our Galaxy;and the Leading Arm,a more diﬀuse HI ﬁlament which leads the Clouds.In terms of HVCs,these features have been studied rather extensively.In this review,I willﬁrst describe the observational results for each complex and subsequently discuss their origin and relationship to the overall HVC population.All of the HI data presented are from the HI Parkes All-Sky Survey (HIPASS)(Barnes et al.2001;Putman et al.2001).2.The Magellanic Bridge2.1.HI STRUCTURE AND KINEMATICSThe Magellanic Bridge is a continuous ﬁlament of HI which stretches from the body of Small Magellanic Cloud (SMC)to an extended arm of the2M.E.PUTMANLarge Magellanic Cloud(LMC)(see Figure1).The Bridge merges almost seamlessly with the SMC,but the boundary between the Bridge and SMC is usually deﬁned at(ℓ,b)=(295◦,−41.5◦)and v LSR=125km s−1,where the loop which extends from the SMC at approximately(ℓ,b)=(297◦,44◦) rejoins the tail of the SMC(also known as Shapley’s wing).This is also the boundary that was originally chosen based on stellar associations(West-erlund&Glaspey1971);however,with the increasing numbers of stellar associations found in the Bridge,this boundary is also somewhat ambigu-ous(see§2.2).The Bridge emerges from the SMC’s tail at the high column densities of1021cm−2and remains clumpy,but gradually decreases in col-umn density to1020cm−2at(ℓ,b)=(287◦,−35.5◦).At this latter position, the Bridge joins with what appears to be an extended spiral arm of the LMC(Kim et al.1998;Putman et al.1999).South of the Bridge in Galac-tic coordinates,especially on the SMC-side,the chaotic beginnings of the Magellanic Stream are present.In general,the Bridge is a more orderly feature than the Stream,possibly representing the Bridge’s shorter history or a more stable environment.The Bridge has an HI mass of approximately 5.5×107M⊙,but this value is highly dependent on whether extensions into the SMC,LMC and Stream are included.The Bridge has a regular velocity gradient along its mainﬁlament,grad-ually increasing in velocity and decreasing in spatial width as it approaches the LMC.Theﬁnal dense pockets of emission do not disappear until350 km s−1at(ℓ,b)=(283◦,−42◦).McGee&Newton(1986)report on line proﬁles which contain up to5components throughout the Bridge(with a velocity resolution of4.1km s−1).They report systematic proﬁle variations in the central Bridge region,but sporadic diﬀerences in the regions of the Bridge which extend into the Magellanic Stream,possibly indicating a more turbulent environment.The presentation of high resolution data has begun with the Australia Telescope Compact Array(ATCA)observations of Sta-nimirovic et al.(1997).Detailed kinematic information will also soon be available with Parkes multibeam narrow-band observations.HI absorption studiesﬁnd that the cool atomic phase gas exists in the Bridge,indicating that the pressure in this region is surprisingly high and that stars may have formed from the Bridge material directly,rather than being drawn out from the SMC(Kobulnicky&Dickey1999).Sensitive CO studies of the Bridge would be an interesting future pursuit.MAGELLANIC HVCS3 2.2.STARS!The Magellanic Bridge is the only HVC which has stars associated with it, and in this respect it may be inaccurate to call it an HVC1.The stars are very scarce and the gas to star ratio remains extremely high,so it is conceiv-able that future stellar searches mayﬁnd stars associated with other HVCs. Early stellar searches in the SMC tail included the discovery of a number of B-type giants and dwarfs(e.g.Sanduleak1969).Searches for blue stars then continued throughout the Bridge(e.g.Irwin et al.1990),and were identi-ﬁed from(ℓ,b)=(296◦,−41◦)to at least(ℓ,b)=(287◦,−36◦).Demers& Battinelli(1998)ﬁnd that the stars in the tail of the SMC(also called the wing)have little distance variation,indicating that it does not have a sub-stantial depth.On the other hand,at the tip of the SMC tail/wing,there are two Bridge associations within17′(300pc at55kpc)which are≈5 kpc apart along the line of sight.In general,the stars in the Bridge show a distance gradient expected for a feature linking the LMC(at50kpc)and the SMC(at60kpc).The stars do not form a continuous link as the HI does,but are found in loose associations scattered throughout the SMC tail and decreasing in number towards the central region of the Bridge.Chemical abundances for the stars in the Bridge were thought to be consistent with an SMC origin(Rolleston et al.1993;Hambly et al.1994); however,recent determinations by Rolleston&McKenna(1999)suggest they are deﬁcient by∼0.6dex compared to similar B-type stars in the SMC.The ages of the Bridge stars range from10-25Myr,much younger than expected if they were torn from the SMC200Myr ago as most tidal models predict.This indicates that the Bridge is actually a star forming region,but searches for ongoing star formation have not yet been success-ful.By considering all of the stars in the Bridge,Grondin et al.(1992)ﬁnd that the Bridge’s IMF is shallower than that of the Milky Way or the Clouds.This favors the formation of massive stars and may indicate that cloud-cloud collisions are the dominant star formation trigger(Scov-ille et al.1986;Christodoulou et al.1997).There has been no detection of a horizontal branch star population in the Bridge,indicating that the halos of the two clouds do not meet(Grondin et al.1992).Kunkel et al.(1997) have found an abundance of intermediate-age(several Gyr)carbon stars scattered throughout the Bridge region,with possible extensions into the beginning of the Stream.Diﬀuse Hαemission also appears to be prevalent in the Bridge region closest to the SMC(Johnson et al.1982;Marcelin et al. 1985),as would be expected with the presence of hot young stars.However, 1Also,although the Bridge is an HVC in the Galactic reference frame,it is not tech-nically an HVC in the Magellanic reference frame,unlike the Stream and Leading Arm.4M.E.PUTMANFigure1.Neutral hydrogen column density map of the Magellanic Clouds and Bridge with the main features discussed in the text labelled.The intensity scale is logarithmic ranging from1021cm−2(black)to2×1018cm−2.there are also several non-detections in the central region of the Magellanic Bridge(Veilleux et al.2001).3.The Magellanic Stream3.1.HI STRUCTURE AND KINEMATICSThe Magellanic Stream,discovered25yrs ago(Wannier&Wrixon1972; Mathewson et al.1974),is a complex arc of neutral hydrogen which starts from the Magellanic Clouds and trails for over100◦.The Stream contains ≈2×108M⊙of neutral hydrogen(at an average distance of55kpc)and has a velocity gradient of over700km s−1from head to tip,390km s−1 greater than that due to Galactic rotation alone.Recent HIPASS obser-vations of the Magellanic Stream provide almost a two-fold improvement in spatial resolution over previous survey data,and depict increasing com-plexity in the Stream’s structure(see Figure2).In particular the maps reveal multipleﬁlaments at the Stream’s head,a twisting ladder structure along the Stream’s length,and small dense clouds which extend20◦from the Stream’s mainﬁlament.A broad overview of the HI properties of the Magellanic Stream is presented below.See Putman et al.(2001)for a full description.The beginning of the Stream is rather chaotic,as it spews out from sev-eral locations north of the SMC and Bridge at v LSR=90−240km s−1(see Figures2&3).There is a slight discontinuity in velocity as the HI enters the Stream from the Bridge.Figure3shows how the Stream becomes more negative in velocity as it extends away from the Clouds,and how there are multiple initialﬁlaments which come to a clumpy end at l≈−60◦andMAGELLANIC HVCS5 v LSR≈85km s−1.The mainﬁlament of the Stream continues towards the South Galactic Pole,where it reaches0km s−1.2It then proceeds north to (ℓ,b)≈(90◦,−40◦),v LSR≈−450km s−1,and column densities of only a few×1018cm−2(versus a few×1019cm−2at the Stream’s head).Relative to the Galactic Center,the radial velocity of the Stream gradually becomes more negative from the head(∼50km s−1)to the tip(∼-200km s−1).The mainﬁlament of the Stream is not as complex as the head,but it is also a complicated structure which appears to be made up of two distinct components.The splitting of the Stream into twoﬁlaments is evi-dent throughout,but is most obvious beyond the multipleﬁlaments at the Stream’s head.The twoﬁlaments run parallel for the length of the Stream and begin to merge towards the tail(much as if one were looking down a long straight road).There are also several horse-shoe shaped structures which join the twoﬁlaments at several positions.This helical structure may represent the orbit of the Magellanic Clouds about each other,with the two ﬁlaments representing material from the Bridge and SMC.Small compact clouds are found throughout Figs.2and3,surround-ing the Stream’s mainﬁlament in both position and velocity.Many of the small clouds,both in and about the Stream,show head-tail structures(i.e.a dense core with a diﬀuse extension of approximately twice the diame-ter of the core(tadpoles))and hollow bow-shock signatures(also noted by Mathewson et al.(1979)).This is especially true at the Stream’s head,with the tails generally pointing away from the Clouds.This could be depicting the Stream’s interaction with the Galaxy’s halo(Pietz et al.1996),or it could simply represent the way the gas has been stripped from the Clouds. Some of the small clouds of positive velocity HI about the South Galac-tic Pole in Figs.2and3are actually galaxies of the Sculptor Group.It has been argued that the abundance of small clouds between these galax-ies are not associated with the Stream,but are members of the Sculptor Group(Mathewson et al.1975;Haynes&Roberts1979).Considering the Stream’s clumpy nature throughout this area,it would be diﬃcult to make a conﬁdent claim of a cloud’s association with the Sculptor Group or other dwarf galaxies(e.g.Carignan et al.1998).However,it is curious how the clumps remain in the southern region of the Sculptor Group from veloci-ties of−240to+240km s−1,and do not follow the Stream as closely in velocity as other clumps along its length.Could these clumps be the rem-nants of an ejection from the Galactic Centre,or possibly intergalactic HI clouds along the Coma-Sculptor-Local Group supergalacticﬁlament(Tully &Fisher1987;Jerjen,Freeman&Binggeli1998)?Hαobservations,metal-2When the Stream’s velocity coincides with that of the Milky Way(≈0km s−1), detailed information is lost in the Galactic emission and in the data reduction,which has problems when the emission completelyﬁlls the scan(see Putman et al.2001).6M.E.PUTMANlicity and distance determinations should help distinguish between these possibilities.The small-scale HI spatial structure of the Stream has not yet been investigated,but ATCA observations are being actively pursued.HIPASS has a velocity resolution of only26km s−1with Hanning smoothing,but higher velocity resolution observations(1km s−1)are in progress with the Parkes narrow-band facility(Br¨u ens et al.2000).Higher velocity resolution observations have also been completed in the past by Haynes(1979),who noted the complex,multi-proﬁle nature of the Stream in the region near the South Galactic Pole,by Cohen(1982),who found the Stream to also have a strong transverse velocity gradient,and by Morras(1983;1985),who noted the bifurcation of the Stream.The northern tip of the Stream was studied by Wayte(1989).He notes the continued bifurcation of the Stream and a complex velocity structure which may indicate that the tail of the Stream is breaking up into many individual clouds at diﬀerent velocities. The line proﬁles of the clouds at the tip show a core/envelope structure reminiscent of some non-Magellanic HVCs(Wakker&vanWoerden1997). If these non-Magellanic HVCs are generally less distant than the majority of the Stream(see van Woerden et al.(1999)for some distances),this change in proﬁle may indicate that the tip of the Stream is getting closer to the Galaxy.Tidal or ram pressure forces may be responsible for stripping oﬀthe clouds’outer layers.3.2.OPTICAL OBSERVATIONSA new method of studying the Magellanic Stream has come with the discov-ery that the Stream can be detected in Hαemission(e.g.Weiner&Williams 1996).The detections vary tremendously in surface brightness(0.04−0.4 Rayleighs),and are usually in regions of high HI column density(>1019 cm−2).There does not appear to be a correlation between the Hαemission measure and HI column density,however the current lack of high-resolution HI data makes this diﬃcult to test.It is possible that Hαemission will be detected beyond the HI contours of the Stream as this has been observed for other complexes(Tufte et al.1998)and may indicate the presence of an ionized sheath.Other lines have also now been detected,including[NII], [SII],and a non-detection of[OIII](Bland-Hawthorn et al.1999).It is not clear how the emission line results should be interpreted.Earlier sugges-tions that ram-pressure is responsible for the Hαemission seem less secure in light of the line ratios and the higher resolution HI maps which show that the strong detections do not always correlate with the leading edges of HI condensations(Putman&Gibson1999).Bland-Hawthorn&Maloney (1999)conclude that shock ionization requires unrealistically high halo den-MAGELLANIC HVCS7 sities at d≈50kpc and suggest ionizing photons from the Galaxy are the main cause for the emission.On the other hand,the Hαemission measures in the Stream are generally∼2times higher than HVCs which have upper distance limits of∼10kpc(Tufte et al.1998).It remains to be seen if the contribution of ionizing photons from the LMC,or the eﬀects of shadowing and nearby spiral arms,can account for this diﬀerence.If the escape of ion-izing photons from the Galaxy and the Magellanic Clouds can be accurately determined,the emission measures can be used to determine the distance to various points along the Stream(Bland-Hawthorn&Maloney1999).A complete map of the Stream’s ionized gas would be a very interesting complement to the HI data presented here.There have been numerous searches for stars which are associated with the Stream,as they might be expected if the Stream were formed via a gravitational interaction.All of the searches for stars within the HI contours of the Stream have been negative,with most of the searches being based on the assumption that the Stream is young and should be populated by A-F stars.Br¨u ck&Hawkins(1983)claimed no stellar Stream counterpart based on star counts down to magnitude20.5in B in the section of the Stream closest to the Clouds.Recillas-Cruz(1982)and Tanaka&Hamajima(1982) did a similar search of the tip of the Stream and found no excess of A-type stars.Guhathakurta&Reitzel(1998)recently used the Keck telescope to complete a deep stellar search in a5′×7′region at(ℓ,b)≈60◦,-68◦(within MS IV)and claimed an upper limit on the Stream’s star-to-gas ratio of0.1 (5%that of the LMC).It is possible that these results are still not deﬁnitive, given the young population of stars searched for in the early searches and the limited area covered by the Keck search;but a more likely explanation is that the HI Stream does not contain stars.There is still the possibility of an oﬀset stellar stream(as seen in many other interacting systems;Hibbard &Yun1999)or a stellar stream that is signiﬁcantly less extended than the Stream due to the initial HI distribution of the Clouds being more extended (Yoshizawa1998).A possible oﬀset stellar tidal counterpart has been found by Majewski et al.(1999),who searched for giant stars about the Clouds and found interesting populations in a region north of the LMC.3.3.METALLICITY&DISTANCE DETERMINATIONSMetallicity and abundance determinations for the Magellanic Stream are consistent with a Magellanic Clouds origin.The Stream’s primary metal-licity determination uses Fairall9as a probe and has been investigated by Gibson et al.(2000),Lu et al.(1994)and Songaila(1981),all of whom obtained consistent results.Recently,Gibson et ed GHRS data and new HI observations to obtain a S/H of0.21solar,extremely close to the8M.E.PUTMANmetallicity of the SMC.They also detected Mg II near the tip of the Stream which indicates that the Stream gas extends at least15◦from the HI shown in Figure2.Lu et al.(1994)found Si/H>∼0.2solar and S/H<∼0.3so-lar along the Fairall9sightline.Theyﬁnd the subsequent Si/S ratio to be greater than or equal to0.6the solar ratio,which indicates that dust deple-tion is not prevalent in the Stream(Si is easily depleted onto dust grains)3. This is consistent with the lack of extinction and infrared emission from the Stream(Fong et al.1987).The extinction result is based primarily on galaxy counts(see also Mathewson et al.1979)and,though inconclusive, the results suggest at most a very small level of extinction.Sembach et al.(2000)have detected O VI associated with the Magellanic Stream,indicating that hot gas must be present.It is very diﬃcult to produce O VI with photoionization and they suggest movement through a hot Galactic halo medium may be responsible.Lu et al.also have a possible detection of C IV absorption at the position of Fairall9.This suggests,along with the Hαdetections discussed above,that the metallicity estimates are subject to an ionization correction.Another uncertainty in the metallicity determinations is the HI column density.The above determinations are based on fairly low spatial resolution HI data(15.′5or34′),and HVCs have been known to vary by a factor ofﬁve in column density on scales of only1′(WvW97).The metallicity determinations remain clear in their indication of the Stream being made up of non-primordial gas and are consistent with the Stream originating from the Magellanic Clouds.Distance estimates for the Stream are based largely on theoretical in-teraction models(see section5.2for a full description).Watanabe(1981) made the assumption that the shape of the Stream clouds(i.e.elongation) is determined by the strength of the Galactic tidal disruption force and estimates the Stream lies between36-50kpc.Hαobservations also have the potential to provide distance information(see section3.2).4.The Leading Arm4.1.HI STRUCTURE AND KINEMATICSThe Leading Arm is made up of a string of clouds on the leading side of the Magellanic Clouds which have only recently been clariﬁed as being connected to each other and the Magellanic System through HIPASS obser-vations(Putman et al.1998).The beginning of the Leading Arm protrudes from the Magellanic Bridge and LMC along several clumpyﬁlaments(see Figure4).The multipleﬁlaments give the appearance that the Leading Arm is associated with both of the Clouds.The Leading Arm is relatively 3They assumed the intrinsic Si/S ratio was the same as the Sun’s.MAGELLANIC HVCS9 Figure2.An integrated intensity map of the Magellanic Stream(v LSR=−400to+400 km s−1),which includes the region shown in Figure1,part of the Leading Arm shown in Figure4and the full extent of the Magellanic Stream.The Stream passes through the velocity of Galactic emission at(ℓ,b)≈315◦,-80◦,and the emission between+/-20 km s−1in this region has been excluded(see Putman et al.(2000)for the channel maps). The intensity values are on a logarithmic scale,with everything above6×1020cm−2 black and the faintest levels at approximately2×1018cm−2.Figure3.Velocity distribution of the Magellanic Stream ranging from-450km s−1(light grey)to380km s−1(dark).thin(∼1/4the width of the trailing Stream),but roughly continuous un-til the Galactic Plane,where it abruptly shifts in Galactic Longitude from 307◦to290◦.The Leading Arm is very clumpy,with diﬀuseﬁlaments con-necting the clumps.Theseﬁlaments were missed in previous surveys due to sparse spatial sampling(Mathewson&Ford1984;Morras1982),and it was thought that the clumps were isolated high-velocity clouds.There are also dense clouds about the mainﬁlament of the Leading Arm(primarily on the lower longitude side),similar to the small clouds which surround the Stream.10M.E.PUTMANThe Leading Arm’s velocity distribution is somewhat confusing,and this may be due to the projection of the feature.It emanates from the Clouds at v lsr≈180km s−1and its velocity steadily increases until it reaches356km s−1at(ℓ,b)=(302◦,−17◦).From this position it decreases in velocity to≈200km s−1as it moves towards the Galactic Plane(see Putman et al.(1998)for channel maps).When the Arm shifts in position by15◦in longitude at the Plane,it also shifts in velocity,starting at≈320km s−1at latitude+8◦and extending to150km s−1at latitude+30◦. Relative to the Galactic Center,the Leading Arm extends in velocity from v gsr=−29to178km s−1.The metallicity determination discussed below suggests that the feature at positive latitudes is a continuation of Magellanic material;however,it is diﬃcult to reproduce the Leading Arm’s initial ∼60◦deﬂection angle from the great circle deﬁned by the Stream,while also retaining the positive latitude clouds as tidal debris(Gardiner1999). Verschuur(1975)suggested that the high positive velocity features which make up the Leading Arm are actually distant spiral features which form an intergalactic bridge between the Clouds and the Milky Way.This seems unlikely since the HIPASS observations show the Leading Arm’s velocity to be distinct from the velocity of the Galactic HI in this direction(∼120 km s−1;Burton1988).It appears as if the data shown in Figure4represent the full extent of the Leading Arm feature,as maps further north of b=30◦do not show any obvious continuation of emission.It is curious that theﬁlament abruptly ends at a relatively high column density;however,there could be more tenuous or fully ionized gas further along.The Leading Arm is not as ordered or massive as the Stream,possibly due to its leading position or age.The mass of the Leading Arm is approximately2×107M⊙,an order of magnitude less massive than the Stream,assuming they are both at the distance of the Magellanic Clouds.High resolution ATCA observations are in progress for many positions along the Leading Arm.Wakker et al.(1999)have already analyzed ATCA data for a position on the positive latitude side of the Plane and found velocity widths of5-10km s−1and column density contrasts of a factor of 3on arc minute scales.They also note the two-component velocity structure of this cloud,similar to other non-Magellanic HVCs,and derive a pressure of18000R−1D−1kpc K cm−3(where R is the resolution in arc minutes and D is the distance to the cloud).Other observations of the Leading Arm include the work of Bajaja et al.(1989),Morras&Bajaja(1983)and Morras(1982); all of which are at a lower spatial resolution but higher velocity resolution than the data shown here.Figure4.A HIPASS peak intensity map which shows the full extent of the Leading Arm,as well as the Magellanic Clouds,the Bridge and the beginning of the Stream(as labelled).The position of the background galaxy,NGC3783,is also noted(see§4.2). To avoid the emission from the Galactic Plane(which extends out to120km s−1in this direction),only velocities between130and400km s−1were used.(Thus the strange appearance of the SMC which begins at≈80km s−1.)Many features are intentionally saturated to bring out the low level emission.It is a linear intensity scale ranging from approximately0.1to2K(black).4.2.METALLICITY DETERMINATIONApart from the fact that the Leading Arm emanates from the Magel-lanic System,the strongest evidence that it is made of Magellanic ma-terial comes from the Lu et al.(1998)metallicity determination for HVC 287.5+22.5+240.Derived from GHRS spectra of the background galaxy NGC3783(see Figure4for position),a S/H of≈0.25⊙was found,consis-tent with the metallicity of the Magellanic Clouds.They also found Fe/H =0.033⊙,with the subsolar Fe/S ratio indicating dust may be present.This ﬁlament lies spatially(and kinematically)in a region where tidal models predict gaseous tidal debris to reside,and the metallicity determination suggests that despite the oﬀset positioning of thisﬁlament,it is indeed part of the Magellanic Leading Arm.The position of the Seyfert galaxy ESO265-G23is another possible background source which can be used to determine the Leading Arm’s metallicity;however it appears to be just oﬀthe HI contours in the HIPASS map(see Putman&Gibson1999).This position may either have a very low column density or represent the ionized medium of the Arm.5.Theoretical Origin Models5.1.BRIDGEIt is generally agreed that the LMC and SMC are bound and that the Bridge was formed via a tidal encounter between the two Clouds(e.g.Gardiner& Noguchi1996(hereafter GN96);Moore&Davis1994).Theﬁnding of stars in the Bridge region supports the tidal model,though the young stellar population may have been born in the Bridge(see§2.2).Few models can simultaneously reproduce both the Bridge and the Stream accurately.GN96 are relatively successful by reﬁning the models of Lin&Lynden Bell(1982) and Murai&Fujimoto(1980).Theyﬁnd that the Magellanic Bridge was most likely pulled from the SMC0.2Gyr ago during a close encounter between the two Clouds(at7kpc separation).The GN96model,in which the SMC is composed of both a disk and a halo,nicely explains the diﬀerent bridge and tail HI components and the velocity distribution of the young (early-type)and old(carbon star)stellar populations.In contrast to GN96,Kunkel et al.(1994)attempt to reproduce the properties of the SMC and Bridge by leaving the LMC and SMC unbound and ignoring the eﬀect of the Galaxy(i.e.they do not reproduce the Mag-ellanic Stream).They suggest that the carbon stars are part of the tidal bridge,separate from the HI and embedded in some type of ionized medium. Heller&Rohlfs(1994)agree with GN96that the two Clouds are bound, but argue that they have remained in a stable binary system for the last 1010years and that tidal forces from the Galaxy were not strong enough to pull out the Magellanic Stream.They suggest the Bridge or intercloud region was formed0.5Gyr ago when there was a close encounter between the LMC and SMC,and this also marks the beginning of the formation of the Magellanic Stream.The chaotic nature of the HI features north of the Bridge(at the head of the Stream)indicates that the Bridge and Stream were not formed in conjunction or that one is pulling material from the other.In the best model of Li(1999),the Clouds have only been gravita-tionally aﬀecting each other for the past2Gyr,as he alsoﬁnds that when the Clouds are a lifelong binary,the interaction between the two Clouds does not allow the Magellanic Stream to form.All of the models assume that the Bridge is made up of material from the SMC,with the LMC ripping material from its less massive companion. The HIPASS data show an extension of the LMC which suggests that the LMC also contributes to the Bridge’s mass(see Figure1).This feature may be reproduced when the potential of the LMC is modelled more realistically.。

地理位置方面的英语作文

Growing up in a small town nestled in the heart of the countryside, Ive always been fascinated by the concept of geography. The way the world is divided into continents, countries, and cities, each with its unique characteristics and history, has always intrigued me. My journey into understanding the importance of geography began with my own hometown and expanded to encompass the wider world.My hometown, with its rolling hills and lush green fields, was my first lesson in geography. I learned about the local flora and fauna, the rivers that crisscrossed the landscape, and the mountains that loomed in the distance. I was amazed by how the geography of my town shaped its culture, economy, and even the daily lives of its inhabitants. The farmers depended on the fertile soil and the changing seasons, while the local industries were influenced by the availability of natural resources.As I grew older, my interest in geography expanded beyond my hometown.I began to study maps and globes, fascinated by the vastness of the world and the diversity of its people. I learned about the different continents, the major rivers and mountain ranges, and the various climate zones. I was particularly drawn to the idea of how geography influences culture, politics, and history.One of the most significant moments in my journey was when I visited a coastal city for the first time. The bustling port, the salty sea air, and the endless horizon were a stark contrast to the quiet countryside I was used to. I was struck by how the proximity to the sea shaped the citys economy, culture, and even the mindset of its people. The city thrived on trade andtourism, and the people had a sense of openness and adventure that I had not encountered before.This experience made me realize the power of geography in shaping the world we live in. The location of a place can determine its climate, its natural resources, and its access to trade routes, all of which can have a profound impact on its development and the lives of its inhabitants. For example, countries with abundant natural resources like oil or minerals often have a different economic trajectory than those without such resources. Similarly, countries located along major trade routes have historically been more prosperous and influential.Moreover, geography can also be a source of conflict and cooperation. Disputes over territory, access to resources, and strategic locations have led to wars and political tensions throughout history. At the same time, shared geography can foster cooperation and integration, as seen in regional blocs like the European Union.In conclusion, geography is an essential aspect of our world that shapes our lives in countless ways. From the local level of my hometown to the global scale of continents and oceans, geography influences our environment, our economies, and our interactions with one another. As I continue to explore the world and learn more about its geography, I am constantly reminded of its power and significance. Whether its the mountains that inspire awe, the rivers that provide sustenance, or the cities that pulse with life, geography is the foundation upon which our world is built.。

乌尤尼天空之镜中英双语

6
This is a wonderful was like a paradise land, not fiction computer scene, but the Uyuni salt lake (Salar de Uyuni) in Bolivia, but also by the United States called "Sky Mirror" is truly showing rhyme.[raim]
Attraction
• 在十月，它是玻利维亚的夏天，美国南部，但也有白色的世界里，是非常适合携带的冬季运动，但没有光泽闪烁的冰，而是盐。 • In October, it’s just summer in Bolivia, South America, but there is also a white world where is very suitable for carrying winter sports here, but there is not shiny flashing ice, but salt.
夏季的雨后，湖面积水，像镜子一样，反射着美丽的令人窒息的天空景色，这就是传说中的“天空之境”的成因。
Climate
•November–January •June •At night 41 °F) •Humidity •Relatively low •Rainfall •April – November per month •January 21 °C (70 °F) 13 °C (55 °F) 9 -- 5 °C (16 --
在乌尤尼盐沼也有许多珍稀野生动物和植物，化石的地质年代，天然地热温泉和酒店完全由盐砖成的。
Attraction

我学会了天意谷作文

我学会了天意谷作文英文回答：Upon embarking on our literary journey through "The Valley of Divine Intent," we encounter a profound and enigmatic realm where human destiny and the tapestry offate intertwine. Throughout this intricate narrative, the interplay of language, culture, and spirituality unfolds before our very eyes, revealing the intricate workings of a world steeped in mysticism and symbolism.The valley, a secluded sanctuary nestled amidst towering peaks and flowing waters, serves as a microcosmfor the human soul. Its inhabitants, each burdened with their own unfathomable past, seek refuge within its sacred confines, hoping to find solace and meaning in a world that often seems incomprehensible.As we delve deeper into the valley's hidden depths, we encounter a cast of characters whose lives are inextricablylinked by a web of unseen forces. There is the enigmatic sage, a guardian of ancient wisdom who guides the lostsouls seeking enlightenment. There is the young woman, haunted by a tragic love affair, who yearns for redemption. And there is the enigmatic wanderer, a solitary figure who traverses the valley, bearing witness to the interconnectedness of all living beings.Through their interactions, these characters confront the fundamental questions that have plagued humanity since time immemorial: the nature of destiny, the power of choice, and the search for meaning in a seemingly chaotic universe. As they navigate the trials and tribulations that befall them, they discover the profound impact that their own actions have on the shape of their lives."The Valley of Divine Intent" is a testament to the enduring power of storytelling. Through its evocative language and nuanced exploration of human nature, it transports us to a realm where the boundaries betweenreality and imagination blur, and where the search fortruth and enlightenment becomes a lifelong quest.中文回答：在《天意谷》这本旷世佳作中，我们踏入一个深邃而神秘的领域，在那里，人类命运与命运的织锦交织在一起。

关于走进大海拥抱世界的英文作文一百字

关于走进大海拥抱世界的英文作文一百字Exploring the Vast Ocean and Embracing Our Wonderful WorldHave you ever stuck your toes into the cool ocean water and felt the soft sand squish between your feet? The ocean is so amazing and full of mysteries waiting to be discovered! That's why I want to become a marine biologist when I grow up. There is still so much about the ocean that we don't understand. By studying it closely, we can learn incredible things about our planet and all the creatures that live in the deep blue sea.Can you imagine being surrounded by marine life of every color, shape and size? Just picture a school of shimmering silver fish darting back and forth. Or a vibrant pink anemone waving its tentacles. Or a playful dolphin leaping out of the water! The ocean is teeming with fascinating animals that are fun to watch.But the ocean isn't just pretty to look at. It's also hugely important for the entire world. It produces over half of the oxygen in the air we breathe! Isn't that wild? The ocean is like the lungs of our planet. Tiny ocean plant creatures called phytoplankton release oxygen as a byproduct when they maketheir own food from sunlight. Without enough phytoplankton, the world's oxygen levels could drop dangerously.The ocean's currents also help regulate temperatures and weather patterns across the globe. Warm and cold ocean currents move heat from the equator towards the poles, preventing the equator from getting too hot and the polar regions from getting too cold. It's like the ocean acts as the world's air conditioning and heating system all in one!Not only that, but the ocean provides food for billions of people. Seafood is a major source of protein and nutrients for many cultures. My family loves sushi night when we get to eat fresh tuna, salmon and shrimp. Some of my friends have only ever tasted fish sticks or tuna fish sandwiches though. I feel bad for them because they're missing out on some seriously tasty dishes!In many ways, the ocean connects all people together, no matter where they live. Ocean currents can carry objects incredible distances, eventually washing them up on distant shores. I read about this exhibit of debris from the 2011 Japanese tsunami that drifted all the way across the Pacific Ocean before landing in Oregon and California. Among the wreckage were bottles, refrigerators, motorcycles and even an entire dock! Itmakes you realize just how small the world can feel sometimes when the ocean's reach is truly global.Seafarers have navigated ocean waters for trade and exploration going back thousands of years to the ancient Greeks, Romans, Phoenicians and more. They were true adventurers who weren't afraid of the unknown. Columbus and other explorers much later were able to make their famous voyages across the Atlantic thanks to innovations in shipbuilding, navigation and maritime technology. The ocean has always represented a exciting frontier full of risks but also great rewards. I'm definitely an explorer at heart, so a career studying and traveling across the ocean would be a dream come true!Even though around 80% of the ocean remains unmapped and unexplored by humans, we've still learned so many unbelievable facts about the mysteries lying under the surface. For example, did you know that the deepest point of the ocean is the Challenger Deep in the Mariana Trench? It plunges down nearly 7 miles below sea level - that's deeper than Mount Everest is tall above sea level! The immense pressure at that depth is absolutely crushing. Can you imagine encountering an alien-like creature that can somehow survive in those intense conditions?There are so many incredible places and species yet to be found in the ocean. Giant squid were considered mythical for a long time before scientists collected evidence proving their existence in the deep. The megamouth shark wasn't discovered until 1976 when the 16-foot beast got caught up in a navy submarine net. And who knows what other bizarre creatures are still hiding out there, like the fantastical objects and monsters depicted in old sailors' tales?Those mythical sea monsters were likely just regular marine animals that seemed scary and unfamiliar to sailors at the time. But the depths of the ocean still represent one of the last great unexplored frontiers on planet Earth. There are mountain ranges, deep trenches, volcanically active hydrothermal vents, lost shipwrecks, and so much more to investigate! With ocean technologies like submersibles improving all the time, more and more of the ocean's secrets are being uncovered.。

用英语描写南海禅寺的作文

Nestled in the serene landscape of the South China Sea, Nanhai Temple stands as a beacon of spiritual tranquility and architectural splendor. The temples history is deeply rooted in the rich cultural tapestry of China, dating back to the Tang Dynasty, and it continues to be a place of pilgrimage and reflection for many.As you approach the temple, the first thing that captures your attention is the majestic gate, adorned with intricate carvings and traditional Chinese motifs. The gate serves as a threshold between the mundane world and the sacred space within, inviting visitors to step into a realm of peace and contemplation.Beyond the gate, the temple grounds unfold like a meticulously crafted garden, with lush greenery, winding pathways, and tranquil ponds that reflect the surrounding beauty. The air is filled with the gentle rustling of leaves and the melodic chirping of birds, creating a symphony of nature that complements the temples serene atmosphere.The main hall of Nanhai Temple is a marvel of traditional Chinese architecture, with its sweeping eaves, upturned roof corners, and vibrant colors that symbolize the harmony between heaven and earth. Inside, the hall is illuminated by the soft glow of candles and the warm light filtering through the paper windows, casting a peaceful ambiance that envelops the visitors.The temple is home to numerous Buddha statues, each with its own unique expression and posture, representing various aspects of Buddhist teachings and philosophy. The most revered statue is the Maitreya Buddha, which stands tall and regal, embodying the qualities of compassion, wisdom, and generosity.In addition to its religious significance, Nanhai Temple is also a treasure trove of cultural and artistic heritage. The walls of the temple are adorned with exquisite murals and calligraphic inscriptions, showcasing the artistic prowess and spiritual depth of the monks and scholars who have visited over the centuries.As you wander through the temple grounds, you cant help but feel a sense of awe and reverence for the centuries of history and devotion that have shaped this sacred space. The Nanhai Temple is not just a place of worship, but also a living testament to the enduring power of faith and the human spirits quest for enlightenment and inner peace.。

科技拉进了人与人的距离英语作文

科技拉进了人与人的距离英语作文In an era where digital footprints are as common as heartbeats, technology has woven an intricate tapestry that connects us in ways previously unimaginable. The advent of smartphones, social media, and instant messaging platforms has not only revolutionized communication but has also bridged the gaps between people, regardless of their geographical locations. The once daunting distance that separated individuals is now just a swipe or a click away, with the power of technology bringing us closer than ever before.The digital age has gifted us with the ability to share our lives in real-time, allowing us to stay updated with the milestones and moments of our loved ones, even when oceanslie between us. Social media platforms like Facebook, Instagram, and Twitter have become the new town squares, where we gather to share stories, ideas, and experiences. The immediacy of these interactions has created a sense of community and belonging that transcends borders and cultures.Moreover, the rise of video conferencing tools like Zoom and Skype has transformed the way we work, learn, and collaborate. Remote work has become a viable option for many, as teams can now meet virtually and brainstorm ideas without the need for physical presence. Students can attend lectures and participate in discussions from the comfort of their homes, breaking down barriers to education that were oncedefined by geographical constraints.In addition, technology has also played a pivotal role in humanitarian efforts, enabling rapid response and support during times of crisis. Disaster relief efforts are coordinated more efficiently, and aid can be mobilizedswiftly through digital networks. The sharing of information and resources has become a lifeline for those in need, showcasing the profound impact that technology can have onour collective well-being.However, it is important to recognize that while technology has brought us closer, it also presents challenges. The digital divide remains a pressing issue for many who lack access to the internet and the devices necessary to connect. Furthermore, the reliance on technology can sometimes lead to a sense of isolation, as virtual connections may not always replace the warmth of face-to-face interactions.In conclusion, the power of technology to bring people together is undeniable. It has transformed our lives, making the world a smaller, more connected place. As we continue to innovate and develop new technologies, it is ourresponsibility to ensure that these advancements areinclusive and beneficial to all, fostering a global community that is truly united by the threads of technology.。

天空为什么会下雨英语作文

天空为什么会下雨英语作文Precipitation: A Journey from Clouds to Earth.The sky above us, an ever-changing canvas, plays host to a multitude of meteorological marvels. Among these phenomena, rain stands out as a vital yet enigmatic process that has intrigued and fascinated humankind for centuries. How does this liquid nourishment descend from the ethereal heights of the atmosphere to quench the thirst of our planet? Embarking on a scientific adventure, we shall unravel the intricate mechanisms behind the celestial dance of precipitation.Cloud Formation: The Genesis of Rain.At the heart of the precipitation process lies the formation of clouds, ethereal agglomerations of microscopic water droplets or ice crystals suspended in the atmosphere. These clouds are born when warm, moisture-laden air rises into the cooler regions of the sky. As the air ascends, itexpands and cools, causing the water vapor it contains to condense into tiny droplets. These droplets, initially too small to be visible to the naked eye, coalesce to formlarger and denser cloud formations.Types of Clouds: A Tapestry of Atmospheric Personalities.Clouds exhibit a wide array of shapes and appearances, each reflecting the unique conditions under which they form. Cirrus clouds, delicate wisps of ice crystals, grace the high skies, while towering cumulonimbus clouds, the behemoths of the atmosphere, herald the impending arrivalof rain or thunderstorms. Stratus clouds, on the other hand, blanket the sky in an unbroken gray sheet, often obscuring the sun's warmth.Condensation and Coalescence: The Growth of Water Droplets.Within the confines of clouds, water droplets undergo a continuous process of growth and coalescence. As aircurrents carry droplets of varying sizes through the cloud, collisions occur, causing smaller droplets to merge with larger ones. Over time, these collisions result in the formation of raindrops, which, heavy with their accumulated mass, embark on their descent towards the earth's surface.Precipitation: The Descent of Liquid Blessings.When raindrops grow sufficiently heavy to overcome the upward force of air resistance, they succumb to gravity's relentless pull and initiate their journey towards the ground. As they fall, they may encounter updrafts that momentarily suspend their descent or downdrafts that accelerate their plummeting trajectory.Types of Precipitation: A Symphony of Watery Forms.The precipitation that reaches the earth's surface manifests in a variety of forms, each with its own distinctive characteristics. Rain, the most familiar form, consists of liquid water droplets with a diameter of approximately 0.5 millimeters. Drizzle, on the other hand,features smaller droplets that measure less than 0.5 millimeters, creating a fine, misty sensation. Snow, a frozen marvel, forms when water vapor directly condenses into ice crystals in the frigid upper atmosphere. Hail, the icy harbinger of thunderstorms, develops when raindrops are carried aloft by strong updrafts and repeatedly freeze and melt as they ascend and descend within the cloud.The Significance of Precipitation: A Lifeline forEarth's Ecosystems.Precipitation plays a pivotal role in the intricate tapestry of life on Earth. Rainwater nourishes vegetation, replenishes aquifers, and provides drinking water for countless organisms. It shapes landscapes, carving rivers and valleys through erosion and weathering. Snow, acting as a natural insulator, protects plants and animals from extreme cold and provides a vital source of water for ecosystems during the spring thaw.Conclusion: An Ode to the Celestial Symphony.Rain, a seemingly simple phenomenon, reveals itself as a complex and fascinating process that connects the heavens and the earth. From the formation of clouds to the descent of raindrops, precipitation weaves an intricate tapestry of meteorological wonder. Its life-giving waters sustain ecosystems, shape landscapes, and quench the thirst of countless beings. As we gaze upon the sky, let us marvel at the celestial symphony of precipitation, a testament to the extraordinary beauty and interconnectedness of our natural world.。

旅行心向大海的英语作文

Traveling towards the sea has always been a dream for many,and for good reason. The vastness of the ocean,its tranquility,and its beauty are unmatched by any other natural landscape.Heres a detailed English essay on the allure of the sea and the experiences it offers.The Call of the SeaFrom a young age,Ive been captivated by the endless horizon where the sky meets the sea.The thought of traveling towards the ocean has always stirred a sense of adventure and freedom within me.The sea,with its vast expanse,represents a world of possibilities, a place where one can escape the confines of the everyday and immerse oneself in the raw,untamed beauty of nature.The Journey BeginsThe journey to the sea is often as thrilling as the destination itself.The anticipation builds as one leaves the urban landscapes behind,trading the noise and chaos for the serene sounds of waves crashing against the shore.The air becomes fresher,the colors brighter, and the world seems to open up as the first glimpse of the ocean comes into view. Exploring the ShorelineUpon reaching the coast,the first thing that strikes you is the sheer scale of the sea.The shoreline stretches out in both directions,seemingly endless.Walking along the beach, with the sand beneath your feet and the sea breeze in your hair,is an experience that connects you to the earth in a profound way.The rhythmic sound of the waves is soothing,and the sight of the seas surface,shimmering under the sun,is mesmerizing. Diving into the DepthsFor the more adventurous,the sea offers the chance to explore its depths.Snorkeling or scuba diving allows one to witness the vibrant marine life that thrives beneath the surface. Coral reefs teem with fish of all shapes,sizes,and colors,creating an underwater world that is as fascinating as it is mysterious.The Solace of the SeaThe sea is not only a place for excitement and exploration it is also a sanctuary for those seeking peace and reflection.Sitting by the shore,watching the sunset over the water,can provide a moment of tranquility that is hard to find elsewhere.The seas constant motionserves as a reminder of lifes ebb and flow,and the sound of the waves can wash away the worries of the day.Cultural EncountersTraveling to coastal regions often means immersing oneself in the local culture.Fishing villages,seaside markets,and coastal cuisine offer a taste of the seas influence on the people who live along its shores.The stories and traditions of these communities are intertwined with the ocean,adding another layer of depth to the travel experience.The Impact of TravelTraveling towards the sea can have a profound impact on ones perspective.It can inspire a sense of awe at the power of nature,a respect for the environment,and a desire to protect the oceans for future generations.The experiences gained from such journeys can lead to a deeper appreciation of the world and our place within it.ConclusionIn conclusion,the sea is more than just a body of water it is a symbol of freedom, adventure,and tranquility.It offers a wealth of experiences that can enrich ones life and broaden ones horizons.Whether its the thrill of exploration,the peace of solitude,or the joy of cultural discovery,the sea has something for every traveler.As I continue to travel towards the sea,I carry with me the memories of the places Ive visited and the lessons Ive learned,knowing that the ocean will always hold a special place in my heart.。