the_chem_proper_of_cyclohexene,cyclohexane_&_benz
北海2024年08版小学六年级下册第三次英语第6单元期末试卷
北海2024年08版小学六年级下册英语第6单元期末试卷考试时间：90分钟（总分:140）A卷考试人：_________题号一二三总分得分一、选择题(共计20题，共40分)1、What is the name of the famous American musician known for "Hello"?A. AdeleB. Taylor SwiftC. Billie EilishD. Rihanna答案：A2、What do we use to make a call?A. PhoneB. ComputerC. TelevisionD. Radio答案:A3、Which of these is a popular sport played with a ball?A. SwimmingB. SoccerC. RunningD. Cycling4、What is the capital of South Korea?A. BeijingB. SeoulC. TokyoD. Hanoi答案:B5、Which of these is not a planet?A. MarsB. SunD. Earth6、选择题：What is the color of a ripe banana?A. GreenB. YellowC. RedD. Brown7、Which shape has four equal sides?A. RectangleB. TriangleC. SquareD. Circle答案：C8、What is the opposite of "hot"?A. ColdB. WarmC. CoolD. Chilly9、Which fruit is yellow and curved?A. AppleB. BananaC. OrangeD. Mango10、What do we call the imaginary line dividing the Earth into Eastern and Western Hemispheres?A. Prime MeridianB. EquatorC. Tropic of CapricornD. Antarctic Circle答案:A11、What is the term for a young monkey?A. InfanB. CubC. KitD. Pup答案:A12、What do you call a place where you can see stars?A. PlanetariumC. ZooD. Aquarium答案:A13、What common kitchen appliance is used for cooking food quickly using steam?A. OvenB. MicrowaveC. StoveD. Toaster答案:B14、What is the freezing point of water?A. 0°CB. 32°CC. 100°CD. -32°C15、What is the main ingredient in guacamole?A. TomatoB. AvocadoC. PepperD. Onion16、Which animal is known for being slow?A. CheetahB. RabbitC. TortoiseD. Dog答案：C17、What is the name of the first man on the moon?A. Buzz AldrinB. Neil ArmstrongC. Yuri GagarinD. John Glenn答案:B18、选择题：What is the capital of Finland?A. HelsinkiB. EspooC. TurkuD. OuluWhat do we call the force that pulls objects toward the Earth?A. GravityB. MagnetismC. FrictionD. Electricity20、Which of these is a winter sport?A. SwimmingB. SkiingC. RunningD. Cycling二、听力题(共计20题，共40分)1、听力题：The chemical structure of a compound determines its ______.2、听力题：The ______ helps with the digestion of carbohydrates.3、听力题：The chemical symbol for aluminum is _______.4、听力题：The capital of Guyana is __________.5、听力题：A _______ is a device that can convert energy from one form to another.6、听力题：A ____ is a tiny creature that hops in gardens.7、听力题：The chemical formula for butane is ______.8、听力题：I like to _____ at the park. (play)9、听力题：The dog is ________ and friendly.10、听力题：The process of filtration is used to separate __________ from liquids.Combustion of hydrocarbons produces _____ (carbon dioxide and water).12、听力题：We like to ________ (play) outside.13、听力题：Fermentation is an anaerobic process that produces _____ and alcohol.14、听力题：I have a _____ (trophy) for my team.15、听力题：The baby is _____ in the stroller. (sitting)16、听力题：The ancient Greeks believed in many ________.17、听力题：The chemical formula for nitric acid is __________.18、听力题：The _______ of light can be tested by examining its spectrum.19、听力题：The __________ is a natural feature that changes over time.20、听力题：In a chemical reaction, the energy required to start the reaction is called the _____ energy.三、填空题(共计20题，共10分)1、填空题：The ancient Egyptians built magnificent ________ (金字塔).2、填空题：The __________ (历史的启迪) sparks curiosity.3、填空题：My cousin is a great __________ (手工艺者).4、填空题：We have a ______ (丰富的) library collection.My __________ (玩具名) always brings me __________ (名词).6、填空题：My favorite drink is ________ (热巧克力) in winter.7、填空题：My dog loves to roll over for a ______ (零食).8、填空题：The ________ was a landmark event in the history of education reform.9、填空题：I love reading ______ (漫画) because they are fun and ______ (有趣).10、填空题：Plants need _____ (养分) from the soil to flourish.11、填空题：The _____ (老虎) has beautiful stripes on its fur.12、填空题：Certain plants offer shade and beauty, enhancing outdoor ______ spaces.(某些植物提供阴凉和美丽，提升户外空间的吸引力。
宁波2024年03版小学三年级T卷英语第一单元自测题
宁波2024年03版小学三年级英语第一单元自测题考试时间：100分钟（总分:120）A卷考试人：_________题号一二三四五总分得分一、综合题(共计100题)1、听力题：The soup is ___ (hot/cold) today.2、填空题：The _____ (灌溉) method can change the health of crops.3、听力题：The three common states of matter are solid, liquid, and _____.4、听力题：The sky is ________ (blue) on a sunny day.5、听力题：My cousin is a ______. She has many pets.6、听力题：The chemical symbol for neptunium is ______.7、听力题：The cat is _____ (小).8、听力题：The chemical symbol for copper is ____.9、填空题：The discovery of ________ has drastically changed our approach to agriculture.10、听力题：The chemical formula for arsenic trioxide is _______.11、What type of animal is a dolphin?A. FishB. ReptileC. MammalD. Amphibian12、What do we call the process of plants making their food?A. DigestionB. PhotosynthesisC. RespirationD. Fermentation答案:B13、填空题：My birthday is in ______ (十月).14、听力题：The kitten is _____ (cute/ugly).15、填空题：The first successful joint transplant was performed in ________.16、听力题：Ants work together to carry _______.17、填空题：A _____ (leaf) changes color in autumn.18、选择题：What do we call the place where animals are kept for public display?A. ZooB. AquariumC. FarmD. Circus19、What do we call the study of the structure and function of cells?A. CytologyB. HistologyC. AnatomyD. Physiology答案:A20、听力题：The Earth has one moon, but Mars has ______.21、What is the name of the animal that hops and has a pouch?A. KangarooB. DogC. CatD. Lion答案: A22、填空题：Certain plants are valuable for their ______ properties, contributing to local economies. (某些植物因其药用特性而有价值，为当地经济做出贡献。
小学上册第六次英语第二单元真题试卷
小学上册英语第二单元真题试卷英语试题一、综合题(本题有100小题，每小题1分，共100分.每小题不选、错误，均不给分)1.What is 2 + 2?A. 3B. 4C. 5D. 6B2.I want to ______ a superhero. (become)3.Which animal is known for its ability to change colors?A. ChameleonB. ElephantC. TigerD. Bear4.Many plants are ______ (多年生) and return each year.5.I can’t wait to show my friends my new ____. (玩具名称)6.Which fruit is yellow and sour?A. AppleB. LemonC. OrangeD. Cherry7.What do we call the process of making fabric from fibers?A. WeavingB. KnittingC. SewingD. SpinningA8.What is the smallest continent?A. AfricaB. EuropeC. AustraliaD. Asia9.I like to run in the ______ (公园) every morning to stay fit.10. A rabbit has long _______ that help it navigate the world.11.What do we call a young crocodile?A. HatchlingB. CalfC. KitD. PupA Hatchling12.What do we use to write on a blackboard?A. PenB. CrayonC. ChalkD. MarkerC13.I love to _____ (study) different plant species.14.Geologists use the term "strata" to refer to ______ of rock layers.15.We go to the ______ (市场) for fresh fruits.16.What is the term for a large body of salt water?A. RiverB. LakeC. OceanD. PondC17.What do we call a machine used to take pictures?A. CameraB. ProjectorC. ScannerD. Television18.I saw a _________ in the garden. (蜗牛)19.What is the capital city of Indonesia?A. JakartaB. BaliC. BandungD. SurabayaA20.My friend, ______ (我的朋友), loves to play basketball.21.The _____ (铁路) connects cities.22.This game is very _______ (有趣).23.I want to _____ (eat/drink) some water.24.How many states are in the USA?A. 50B. 51C. 52D. 4825. A chemical _______ shows how substances react with each other. (反应式)26.The bee is _____ on the flower. (buzzing)27.I enjoy ______ (与家人一起) playing sports.28.I enjoy playing with my ______ (玩具车) in the living room. It goes ______ (快).29.The classroom is ________ and bright.30.What do frogs live in?A. TreesB. WaterC. DesertD. CavesB31.What is the name of the fairy tale character with long hair?A. Snow WhiteB. RapunzelC. BelleD. ArielB32.The chemical formula for potassium permanganate is _____.33.The _____ (叶片) can be broad or narrow.34.The chemical formula for ammonium phosphate is _____.35.Wildflowers grow __________ (自然) in meadows.36.The cake is ________ (非常好吃).37.I see a _______ (fox) in the distance.38.The capital of Cabo Verde is __________.39.The ancient Egyptians used _______ to write on. (纸草)40.What is the name of the ship that sank in 1912?A. LusitaniaB. TitanicC. BritannicD. MayflowerB41.We will visit our ______ (uncle) next weekend.42. A balanced chemical equation has the same number of ______ on both sides.43.Curtain symbolized the divide between ________ (东西方). The Kore44.Table sugar is also known as _____.45.What do you call the movement of air?A. WindB. BreezeC. StormD. CurrentA46.I like to practice ______ (瑜伽) to relax and stay healthy.47.How many letters are in the word "elephant"?A. 6B. 7C. 8D. 9答案:B48.My ________ (玩具名称) is a source of inspiration.49.The Sahara is the largest _______ in Africa.50.The _______ (The Enlightenment) emphasized reason and individualism.51.The chemical symbol for germanium is __________.52.What is the name of the longest river in the world?A. AmazonB. NileC. MississippiD. YangtzeB53.What is the name of the famous Egyptian structure built as a tomb?A. ColosseumB. Great WallC. PyramidD. Taj MahalC54.He is a firefighter, ______ (他是一名消防员), responding to emergencies.55.Which day comes after Friday?A. MondayB. SaturdayC. SundayD. ThursdayB56.The first human-made object to land on the moon was _______.57.What is the fastest land animal?A. ElephantB. CheetahC. HorseD. KangarooB58.The ______ teaches us about scientific discoveries.59.How many bones are in a child's body?A. 206B. 205C. 300D. 25060.What is the capital of Greece?A. AthensB. ThessalonikiC. CreteD. Rhodes61. A __________ is a substance that can conduct electricity when dissolved in water.62.The __________ is a major geographical region in Africa. (撒哈拉沙漠)63.The _____ (营养) from the soil is vital for growth.64.The teacher gives us _____ for homework. (assignments)65.The ice is very ___. (slippery)66. A hamster's cheeks can hold a lot of ______ (食物).67.My favorite game is ________ (视频游戏) on the computer.68.The water is ________ in the lake.69.What is the name of the device we use to listen to music?A. RadioB. TelevisionC. ComputerD. PhoneAA. CombB. ToothbrushC. TowelD. SpoonB71.What is 7 + 8?A. 16B. 15C. 14D. 13A72.The ______ (蓝鲸) is known to be the largest animal ever.73. A frog's legs help it swim and ______ (跳).74.I enjoy going to ______ with my family.75.We have a _____ (活动) this weekend.76.The capital of Sri Lanka is __________.77.What is the opposite of 'happy'?A. SadB. ExcitedC. AngryD. Joyful78. A _______ is a measure of the amount of solute in a solution.79.The ________ (地理学) is fascinating to study.80.My brother loves __________ (学习新技能).81.In the spring, I see many ______ (蝴蝶).82.The children are ___ a game. (playing)83.The ____ is a small rodent that likes to nibble on seeds.84. A ______ (松鼠) stores nuts for winter.85.What do farmers grow?A. BooksB. CropsC. CarsD. ClothesB86.The Earth's atmosphere is made up of different gases, primarily ______.87.Which season comes after spring?A. WinterB. SummerC. FallD. Autumn88.Which shape has three sides?A. SquareB. CircleC. TriangleD. RectangleCA. HatB. ShoesC. GlovesD. ScarfB90.They are going to ________ the zoo.91.The _____ (袋鼠) carries its baby in a pouch.92. A _______ is a solution that cannot dissolve any more solute.93.Which animal is known for its ability to change color?A. ChameleonB. EagleC. SharkD. PenguinA Chameleon94.My ________ (玩具名称) is a celebration of fun.95.The first man on the moon was __________ (尼尔·阿姆斯特朗).96.What do we call a baby llama?A. CalfB. FoalC. CriaD. KidC Cria97.Which animal is known for its ability to hop?A. FrogB. DogC. CatD. FishA98.The chemical formula for hydrochloric acid is ________.99.We will _______ (join) the club.100.What do we call the process of making a choice?A. Decision-makingB. PlanningC. OrganizingD. ArrangingA。
西安“PEP”2024年小学六年级第8次英语第一单元期中试卷
西安“PEP”2024年小学六年级英语第一单元期中试卷考试时间：100分钟（总分:120）B卷一、综合题(共计100题共100分)1. 选择题：Which of these is a type of fish?A. SalmonB. ChickenC. PorkD. Beef答案:A2. 填空题：The __________ (历史的交汇) creates possibilities.3. 填空题：The ________ likes to swim in the pool.4. 选择题：How many days are in a leap year?A. 365B. 366C. 367D. 364答案:B5. 听力题：A ______ is a homogeneous mixture of two or more substances.6. 填空题：My mom grows ________ in the kitchen.7. 听力题：A __________ is a piece of land surrounded by water on all sides.8. 填空题：Vines can _____ (攀爬) up walls.9. 听力题：The chemical formula for calcium carbonate is ______.10. 填空题：The ________ is a significant structure in London.11. 选择题：What do you call the person who writes a book?A. ReaderB. AuthorC. EditorD. Publisher答案: B. Author12. 填空题：The __________ (历史的反馈) influences future research.13. 选择题：What do you call a story about a person's experiences?A. NarrativeB. BiographyC. AutobiographyD. All of the above答案:D14. 听力题：My uncle loves collecting ____ (comic books).15. 填空题：My uncle is a __________ (电工).16. 听力题：The _______ changes with the seasons.17. 填空题：We celebrate my brother’s __________ every year. (生日)18. 填空题：The cat's purring is a sign of ______ (放松).19. 选择题：What do you call the process of making bread rise?A. FermentationB. ProofingC. KneadingD. Mixing20. 填空题：I love to play ______ outside.21. 听力题：__________ are substances that can conduct electricity when dissolved in water.22. 听力题：The __________ can provide critical insights into the impacts of climate change.23. 听力题：The capital of Georgia is __________.24. 听力题：The chemical symbol for silver is ______.25. 听力题：The caterpillar turns into a _____.26. 填空题：The first human to break the sound barrier was ______ (查尔斯·扬)。
化学化工英语试题及答案
化学化工英语试题及答案一、选择题（每题2分，共20分）1. Which of the following is a chemical element?A. WaterB. OxygenC. HydrogenD. Carbon答案：B, C, D2. The chemical formula for table salt is:A. NaOHB. NaClC. HClD. NaHCO3答案：B3. What is the process called when a substance changes from a solid to a liquid?A. SublimationB. VaporizationC. MeltingD. Condensation答案：C4. In the periodic table, which group contains alkali metals?A. Group 1B. Group 2C. Group 17D. Group 18答案：A5. What is the name of the process where a substance decomposes into two or more substances due to heat?A. CombustionB. OxidationC. ReductionD. Decomposition答案：D6. Which of the following is a physical property of a substance?A. ColorB. TasteC. SolubilityD. Reactivity答案：A7. What is the term for a compound that releases hydrogen ions (H+) when dissolved in water?A. BaseB. AcidC. SaltD. Neutral答案：B8. The law of conservation of mass states that in a chemical reaction:A. Mass is lostB. Mass is gainedC. Mass remains constantD. Mass can be converted into energy答案：C9. Which of the following is a type of chemical bond?A. Ionic bondB. Covalent bondC. Hydrogen bondD. All of the above答案：D10. What is the name of the process where a substance absorbs energy and changes from a liquid to a gas?A. MeltingB. VaporizationC. SublimationD. Condensation答案：B二、填空题（每题2分，共20分）1. The symbol for the element iron is ________.答案：Fe2. The pH scale ranges from ________ to ________.答案：0 to 143. A compound that produces a basic solution when dissolvedin water is called a ________.答案：base4. The smallest particle of an element that retains its chemical properties is called a ________.答案：atom5. The process of separating a mixture into its individual components is known as ________.答案：separation6. The study of the composition, structure, and properties of matter is called ________.答案：chemistry7. The process of a substance changing from a gas to a liquid is called ________.答案：condensation8. A(n) ________ reaction is a type of chemical reactionwhere two or more substances combine to form a single product. 答案：synthesis9. The volume of a gas at constant temperature and pressureis directly proportional to the number of ________.答案：moles10. The process of converting a solid directly into a gas without passing through the liquid phase is known as ________. 答案：sublimation三、简答题（每题10分，共30分）1. Explain what is meant by the term "stoichiometry" in chemistry.答案：Stoichiometry is the calculation of the relative quantities of reactants and products in a chemical reaction.It is based on the law of conservation of mass and involvesthe use of balanced chemical equations and the molar massesof substances to determine the amounts of reactants needed to produce a certain amount of product or the amounts ofproducts formed from a given amount of reactant.2. Describe the difference between a physical change and a chemical change.答案：A physical change is a change in the state or form of a substance without altering its chemical composition. Examples include melting, freezing, and boiling. A chemical change, on the other hand, involves a change in the chemical composition of a substance, resulting in the formation of new substances. Examples include combustion and rusting.3. What are the three main types of chemical bonds, and givean example of each.答案：The three main types of chemical bonds are ionic bonds, covalent bonds, and metallic bonds. An ionic bond is formed when electrons are transferred from one atom to another, resulting in the formation of oppositely charged ions. An example is the bond between sodium (Na) and chloride (Cl) in table salt (NaCl). A covalent bond is formed when two atoms share electrons, as seen in water (H2O) where hydrogen atoms share electrons with oxygen. Metallic bonds occur in metals, where a "sea" of delocalized electrons is shared among positively charged metal ions, as in sodium metal。
化学英语考试题及答案
化学英语考试题及答案一、选择题（每题2分，共20分）1. What is the chemical symbol for oxygen?A. OB. OHC. H2OD. O22. Which of the following is not a basic unit of a chemical element?A. AtomB. MoleculeC. ProtonD. Electron3. What is the law of conservation of mass?A. Mass is neither created nor destroyed in a chemical reaction.B. Mass is always created in a chemical reaction.C. Mass is always destroyed in a chemical reaction.D. None of the above.4. What is the correct chemical formula for water?A. H2OB. H2O2C. O2HD. OH-5. Which of the following is a noble gas?A. Oxygen (O)B. Helium (He)C. Carbon (C)D. Nitrogen (N)6. What is the valency of hydrogen in the compound HCl?A. +1B. -1C. +2D. -27. Which of the following is a compound?A. Oxygen gas (O2)B. Carbon dioxide (CO2)C. Hydrogen gas (H2)D. Nitrogen gas (N2)8. What is the common name for the chemical NaCl?A. SodiumB. ChlorineC. Table saltD. Baking soda9. What is the atomic number of carbon?A. 6B. 16C. 12D. 810. What is the process of a substance changing from a solidto a liquid state called?A. SublimationB. VaporizationC. MeltingD. Condensation二、填空题（每空1分，共10分）11. The chemical equation for the combustion of methane is__________.Answer: CH4 + 2O2 → CO2 + 2H2O12. The symbol for the element with atomic number 17 is__________.Answer: Cl13. The process of a substance changing from a liquid to agas is known as __________.Answer: Vaporization14. The chemical formula for calcium carbonate is __________. Answer: CaCO315. The valency of chlorine in the compound KCl is __________. Answer: -116. The noble gas that is used in balloons is __________.Answer: Helium (He)17. The atomic number of oxygen is __________.Answer: 818. The process of a substance changing from a gas to aliquid is known as __________.Answer: Condensation19. The chemical symbol for the element with the highest atomic mass is __________.Answer: Og (Oganesson)20. The law that states the total mass of the reactants equals the total mass of the products in a chemical reaction is known as the __________.Answer: Law of Conservation of Mass三、简答题（每题5分，共20分）21. Explain the difference between a pure substance and a mixture.Answer: A pure substance consists of a single type of particle, while a mixture is composed of two or moredifferent substances that are not chemically combined.22. What is an acid and what are its properties?Answer: An acid is a substance that donates hydrogen ions (H+) when dissolved in water. Properties of acids include a sour taste, the ability to change the color of certain indicators, and the ability to react with bases to form salts and water.23. Describe the process of photosynthesis.Answer: Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll pigments. It involves theconversion of carbon dioxide and water into glucose and oxygen in the presence of light energy.24. What is a chemical equilibrium and how is it represented? Answer: Chemical equilibrium is the state in a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction, resulting in no net change in the concentrations of reactants and products. It is represented by the equilibrium constant expression, Kc, which is the ratio of the concentrations of products to reactants raised to their respective stoichiometric coefficients.四、计算题（每题5分，共10分）25. If 10 grams of sodium bicarbonate (NaHCO3) are dissolved in water and reacted with an excess of hydrochloric acid (HCl), calculate the volume。
The Chemistry of Green Synthesis and Catalysis
The Chemistry of Green Synthesis andCatalysisIntroductionThe modern world is facing many environmental problems caused by human activities. Environmental pollution, climate change, and depletion of natural resources are the major concerns. To address these issues, scientists are exploring ways to develop sustainable technologies and practices. The field of green chemistry aims to reduce the environmental impact of chemical processes by minimizing waste, using renewable resources, and reducing toxic substances. Green synthesis and catalysis are two important subfields of green chemistry, which have great potential for sustainable development.What is Green Synthesis?Green synthesis refers to the development of chemical reactions that are environmentally benign and sustainable. It involves using renewable resources, reducing the use of hazardous chemicals, and minimizing waste. Green synthesis is important because traditional chemical processes are often resource-intensive, produce large amounts of waste, and use toxic solvents, which can have adverse effects on human health and the environment.Green synthesis can be achieved by several methods, including using bio-based feedstocks, replacing hazardous solvents with benign ones, using microwave or ultrasound-assisted reactions, and using catalysts. Catalysts are an important tool in green synthesis, as they often allow the reaction to proceed more efficiently and with fewer environmental impacts.What is Catalysis?Catalysis is the process of accelerating a chemical reaction by adding a substance known as a catalyst. A catalyst works by lowering the activation energy required for the reaction to occur. It does not affect the thermodynamics of the reaction and is notconsumed in the reaction. Therefore, catalysts can be used repeatedly to speed up reactions without being depleted.Catalysis plays a crucial role in many industrial processes, including the production of fuels, polymers, and pharmaceuticals. However, traditional catalytic processes often use high temperatures and pressures, require toxic solvents, and produce hazardous waste. This is where green catalysis comes in.What is Green Catalysis?Green catalysis is a branch of green chemistry that focuses on developing sustainable catalysts and catalytic processes. Its goal is to reduce the environmental impact of catalytic reactions by using renewable resources, minimizing waste and toxicity, and improving efficiency.Green catalysis has many benefits over traditional catalysis. For example, it can reduce energy consumption and therefore lower greenhouse gas emissions. It can also use non-toxic and renewable resources, which can reduce the environmental impact of the reaction. In addition, green catalysis often uses less hazardous solvents, which improves the safety of the reaction for workers and reduces the risk of contaminated waste.Green Synthesis and Catalysis in ActionThere are many examples of green synthesis and catalysis being used in industrial processes. For example, the production of biodiesel is a green synthesis process that uses vegetable oil or animal fat as a renewable feedstock. The reaction is catalyzed by sodium hydroxide or potassium hydroxide, which are both inexpensive and non-toxic catalysts.Another example is the production of pharmaceuticals using enzyme catalysis. Enzymes are biocatalysts that work under mild conditions of temperature and pressure and produce little or no waste. Their use in the production of pharmaceuticals can reduce the environmental impact of the process and improve the safety for workers.ConclusionGreen synthesis and catalysis are two important subfields of green chemistry that have great potential for sustainable development. By using renewable resources, minimizing waste and toxicity, and improving efficiency, these processes can reduce the environmental impact of chemical reactions. Green synthesis and catalysis are already being used in many industrial processes, and their use is likely to increase in the future as the demand for sustainable technologies and practices grows.。
小学下册Y卷英语第4单元真题[含答案]
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小学下册英语第4单元真题[含答案]考试时间：90分钟（总分:120）B卷一、综合题(共计100题共100分)1. 听力题：I like to _____ (swim) in summer.2. 填空题：I love _____ (eating) fresh fruits and vegetables.3. 听力题：A ______ is a natural feature that influences local ecosystems.4. 选择题：What do we call the part of our body that helps us breathe?A. HeartB. LungsC. LiverD. Stomach答案:B5. 选择题：What is 5 + 3?A. 6B. 7C. 8D. 9答案:C6. 选择题：What do we call the soft material that covers the ground in a forest?A. SoilB. SandC. GrassD. Moss答案:DHow many days are there in a week?A. 5B. 6C. 7D. 8答案:C8. 听力题：A chemical that can act as a reducing agent is called a ______.9. 听力题：A chemical reaction can occur when reactants collide with sufficient ______.10. 听力题：We go to school by ______ (bus).11. 填空题：The pelican has a big _______ (嘴巴).12. 选择题：What do you call the process of water turning into vapor?A. PrecipitationB. EvaporationC. CondensationD. Freezing答案:B13. 听力题：A __________ is a small animal that loves to dig.14. 填空题：My brother always helps me ____.15. 听力题：The ________ (expedition) is adventurous.16. 填空题：The __________ was an important event in the fight for independence in Latin America. (独立战争)17. 填空题：Ancient Greece is known for its contribution to _______ (philosophy) and arts.18. 填空题：A caterpillar turns into a ______.What is the capital of Italy?A. RomeB. ParisC. MadridD. Lisbon20. 听力题：The chemical formula for calcium phosphate is ______.21. 选择题：Which season comes after winter?A. SummerB. FallC. SpringD. Autumn答案:C22. 选择题：What is the capital city of France?A. MadridB. BerlinC. ParisD. Lisbon答案:C23. 选择题：How do you say hello in Spanish?A. BonjourB. CiaoC. HolaD. Guten Tag答案:C24. 听力题：The color of litmus paper turns red in ______ solutions.25. 选择题：What type of animal is a dolphin?A. FishB. MammalC. ReptileD. Bird26. 听力题：I _____ (like/hate) broccoli.I have a _____ (遥控车) that can spin.28. 听力题：The ______ is known for her motivational speeches.29. 填空题：Planting in rows can help with ______ and maintenance. (成排种植可以帮助管理和维护。
青岛“PEP”2024年小学五年级上册第4次英语第二单元期中试卷
青岛“PEP”2024年小学五年级上册英语第二单元期中试卷考试时间：100分钟（总分:140）A卷考试人：_________题号一二三四五总分得分一、综合题(共计100题)1、What is the opposite of right?A. WrongB. CorrectC. TrueD. Accurate答案:A2、听力题：The reaction of acids with metals is often used to produce ______.3、听力题：The chemical formula for ammonium phosphate is _______.4、填空题：A wolf's howl can be heard over long ________________ (距离).5、听力题：The _______ needs sunlight to grow tall.6、What is the name of the bear species that lives in the Arctic?A. Grizzly BearB. Polar BearC. Black BearD. Brown Bear答案:B. Polar Bear7、听力题：Leaves capture _______ from the sun.8、What is the name of the event where you celebrate a new beginning?A. GraduationB. WeddingC. BirthdayD. New Year答案: D9、填空题：We have ______ (许多) animals in the zoo.10、What is the main function of the roots of a plant?A. To produce flowersB. To absorb nutrients and waterC. To support the plantD. To attract pollinators答案: B11、填空题：I like to _______ (参加) science fairs.12、填空题：A _____ (章鱼) can change its shape to fit through tight spaces.13、填空题：I saw a _______ (蜘蛛) spinning a web.14、听力题：She has long ______ (hair).15、听力题：I have a new ___. (computer)16、听力题：The ________ (mountaineer) climbs high peaks.17、填空题：He is a _____ (作家) who writes poetry.18、填空题：The first people to settle in Australia were the __________ (土著).19、听力题：A mountain is a large landform that rises ______ above the surrounding land.20、填空题：I enjoy ______ (学习) about different subjects.21、听力题：Some plants can grow in _______ water.22、听力题：My mom likes to _____ new recipes. (try)23、填空题：My ________ (玩具) helps me learn about colors.24、What is the capital city of Slovenia?A. LjubljanaB. MariborC. CeljeD. Kranj25、填空题：The __________ (历史的思维模式) inspires innovation.26、填空题：She has a beautiful _______ (声音).27、What is the capital of Puerto Rico?a. San Juanb. Poncec. Bayamónd. Mayagüez答案:a28、选择题：What is the name of our planet?A. MarsB. EarthC. VenusD. Jupiter29、What is the name of the famous English playwright?A. Charles DickensB. J.K. RowlingC. William ShakespeareD. Mark Twain答案：C30、选择题：What do you call the person who teaches you in school?A. DoctorB. TeacherC. EngineerD. Chef31、填空题：The __________ (历史的研究领域) continues to grow.32、填空题：My pet likes to play with my _________ (绒毛玩具).33、填空题：A wolverine is a strong ______ (动物).34、听力题：They ride their _____ (bikes) to school.35、填空题：I have a toy ________ that can walk.36、填空题：A goldfish can live in a ______ (鱼缸).37、What is the name of the famous bed and breakfast in "The Shining"?A. Overlook HotelB. Bates MotelC. The Stanley HotelD. The Grand Budapest Hotel答案: A38、听力题：The chemical formula for hydrochloric acid is _______.39、What do we call the top layer of soil?A. BedrockB. SubsoilC. TopsoilD. Humus答案: C40、听力题：The Earth's layers interact in various ______ ways.41、听力题：A compound that can donate protons is called an ______.42、填空题：________ (植物资源开发) benefits communities.The ________ (生态影响监测) keeps track of changes.44、What is the symbol for the element oxygen?A. OB. OxC. O2D. O3答案:A45、填空题：I like to __________ (动词) my __________ (玩具名) before bedtime.46、填空题：The _____ (花蕾) opens to reveal blossoms.47、填空题：My friend is __________ (具有创造力).48、What is the opposite of "fast"?A. QuickB. SlowC. RapidD. Swift答案: B49、填空题：A _______ (螃蟹) walks sideways.50、填空题：在中国历史中，________ (philosophers) 的思想对社会发展产生了深远的影响。
哈佛大学高等有机化学讲义Lecture15
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D. A. Evans
Cycloaddition Reactions: Part–1
s Other Reading Material:
应用化学专业英语第一单元The-Roots-Of-Chemistry
The Roots Of ChemistryChemistry can be broadly defines as the science of molecules and their transformations.化学可以广泛地定义为科学的分子和他们的转换。
In contrast to mathematics,chemistry is older than people. 与数学不同，化学比人类更久远。
The appearance of life and people on our planet (earth) is most probably the end result of specific chemical processes .生命的出现和人类生活在我们地球上都最可能是特殊化学过程的结果。
Chemical processes have been present in the lives of people from the dawn of history until the present time .化学过程存从古至今存在人们的生活中。
Initially ,these processes were not under our control 最初，这些过程不受我们的控制，,for instance ,the fermentation of fruit juice,the rotting of meat and fish ,and the burning of wood .例如，果汁的发酵，肉和鱼的腐烂，木材的燃烧。
Later on we learned to control chemical processes and to use them to prepare a variety of different products such as food ,metals ,ceramics and leather .后来，我们学着控制化学过程，用它们来准备一系列不同的产品例如食物。
成都2024年05版小学四年级K卷英语第3单元期末试卷
成都2024年05版小学四年级英语第3单元期末试卷考试时间：90分钟（总分:120）A卷一、综合题(共计100题)1、What is the capital of Slovakia?A. PragueB. BratislavaC. BudapestD. Ljubljana答案:B. Bratislava2、What type of animal is a dolphin?A. FishB. MammalC. ReptileD. Amphibian答案: B3、听力题：The symbol for barium is _____.4、How do you say "good morning" in Italian?A. BuongiornoB. BuonaseraC. BuonanotteD. Ciao5、填空题：The ________ is a tiny creature that flies.6、What is the term for the distance around a circle?A. DiameterB. RadiusC. CircumferenceD. Area答案:C7、听力题：The _____ (市场) has fresh produce.8、What kind of animal is an octopus?A. MammalB. FishC. ReptileD. Mollusk答案: D9、填空题：My uncle is a skilled __________ (修理工).10、What do you use to write on paper?A. PaintB. PencilC. GlueD. Scissors答案:B11、听力题：I have a _____ of jellybeans. (bag)12、听力题：My ______ tells me about different cultures.13、听力题：The first permanent English settlement in America was _______.14、What is the name of the famous American author known for his works on adventure?A. Mark TwainB. Ernest HemingwayC. F. Scott FitzgeraldD. John Steinbeck答案:A15、听力题：The ______ is a great motivator.16、听力题：The sun is ________ in the sky.17、What do we call the process of breaking down food in the body?A. DigestionB. AbsorptionC. AssimilationD. Ingestion答案: A18、填空题：The ______ (香味) of fresh herbs can enhance cooking.19、Which animal can fly?A. FishB. BirdC. DogD. Cat20、What do we celebrate on July 4th in the USA?A. ThanksgivingB. Independence DayC. ChristmasD. New Year答案:B21、填空题：The __________ (森林) helps clean the air.22、What is the opposite of ‘big’?A. LargeB. SmallC. HugeD. Tall23、填空题：I love to play ________ (桌游) with my family.24、Which animal is known for its ability to fly south for the winter?A. PenguinB. EagleC. SparrowD. Dolphin答案:C25、填空题：He is _______ at playing soccer.We should always be ________ (尊重) to others.27、听力题：The bumblebee collects pollen from _______.28、听力题：The Earth is the _____ planet from the sun.29、听力题：I like to _____ (ride/drive) my bike.30、What do we call the light given off by the sun?A. MoonlightB. StarlightC. SunlightD. Firelight答案:C31、填空题：The turtle is slow but very _______ (智慧).32、Which of these is a frozen dessert?A. CakeB. Ice creamC. CookieD. Pie答案:B33、填空题：My mother is a _____ (作家) and publishes books.34、选择题：What is the name of the famous painter known for his artwork of the Mona Lisa?A. Vincent van GoghB. Pablo PicassoC. Leonardo da VinciD. Claude Monet35、What is the name of the famous television show featuring a group of friends living in New York City?A. FriendsB. SeinfeldC. How I Met Your MotherD. The Office答案: AWe share our ___ (toys).37、Sea is a ________ (盐水湖). 填空题：The Dead38、What do you call a person who repairs computers?A. TechnicianB. EngineerC. ProgrammerD. Developer答案:A39、填空题：My __________ (玩具名) is great for __________ (活动).40、What is the color of a typical eggplant?A. GreenB. YellowC. PurpleD. Red答案:C41、填空题：The kangaroo keeps its baby in its _________ (育儿袋).42、听力题：A __________ is a geological feature that can shape human activities.43、选择题：Which creature is known for spinning webs?A. AntB. SpiderC. BeeD. Fly44、How many colors are in the flag of Canada?A. OneB. TwoC. ThreeD. Four45、填空题：I love going to the ______ (艺术展) to see incredible works. It inspires my creativity.古代的________ (cultures) 通过艺术和宗教信仰表达自我。
高等有机化学：6.4 消除反应 (Elimination Reaction)
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（2）β-消除
消除主要形式
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Saytzev's rule: The preferred alkene is the isomer bearing the greatest number of alkyl groups attached to the double bond. Hoffmann's elimination: When an alkene is formed by heating a quaternary ammonium hydroxide the preferred isomer is that bearing the smallest number of alkyl groups at the double bond.
化学专英试题及答案
化学专英试题及答案一、选择题（每题2分，共10分）1. The term "stoichiometry" refers to the:A. Study of chemical reactionsB. Calculation of amounts of reactants and products in chemical reactionsC. History of chemistryD. Physical properties of substances2. Which of the following is not a state of matter?A. SolidB. LiquidC. GasD. Energy3. The SI unit for the amount of substance is the:A. CoulombB. JouleC. MoleD. Newton4. In the periodic table, elements are arranged in order of increasing:A. Atomic massB. Atomic numberC. ElectronegativityD. Ionization energy5. The process of converting a solid to a liquid is called:A. SublimationB. VaporizationC. MeltingD. Decomposition二、填空题（每空1分，共10分）1. The chemical symbol for the element oxygen is ________.2. The law that states that the volume of a gas is directly proportional to the number of molecules is known as________'s law.3. The process of a substance changing from a liquid to a solid is called ________.4. The pH scale ranges from ________ to ________, with 7 being neutral.5. A compound that releases hydrogen ions when dissolved in water is known as an ________.三、简答题（每题5分，共20分）1. Explain what is meant by the term "valency" in chemistry.2. Describe the difference between a physical change and a chemical change.3. What is the significance of the Avogadro's number in chemistry?4. Discuss the role of catalysts in chemical reactions.四、计算题（每题10分，共20分）1. If 5 moles of a gas occupy 22.4 liters at standard temperature and pressure (STP), calculate the volume occupied by 10 moles of the same gas at STP.2. A 1.5 M solution of hydrochloric acid (HCl) is mixed witha 3.0 M solution of sodium hydroxide (NaOH) in a 1:1 volume ratio. Calculate the molarity of the resulting solution.五、实验题（每题15分，共30分）1. Describe a laboratory procedure to test for the presence of chloride ions in a solution.2. Outline the steps to prepare a standard solution of potassium permanganate (KMnO4) for titration.答案：一、选择题1. B2. D3. C4. B5. C二、填空题1. O2. Boyle3. Solidification4. 0, 145. Acid三、简答题1. Valency refers to the combining power of an element, which is the number of hydrogen atoms it can combine with or replace in a chemical reaction.2. A physical change is a change in the state or form of a substance without altering its chemical composition, while a chemical change involves a transformation that results in theformation of new substances.3. Avogadro's number (6.022 x 10^23) is significant becauseit represents the number of particles (atoms, molecules, ions, etc.) in one mole of a substance.4. Catalysts are substances that increase the rate of a chemical reaction without being consumed in the process, thus facilitating the reaction without altering the overall chemical equilibrium.四、计算题1. 44.8 liters2. 0.75 M五、实验题1. To test for chloride ions, add a small amount of silver nitrate solution to the test solution. If a white precipitate forms, it indicates the presence of chloride ions.2. To prepare a standard solution of KMnO4, dissolve a known mass of the compound in a minimal amount of distilled water, then dilute it to a known volume in a volumetric flask. The concentration can be calculated using the mass and volume of the solution.。
生物专业英语试题及答案
生物专业英语试题及答案一、选择题（每题2分，共20分）1. Which of the following is not a type of cell organelle?A. MitochondriaB. NucleusC. RibosomeD. Cell wall2. The process of DNA replication is catalyzed by:A. PolymeraseB. TransposaseC. LigaseD. Helicase3. In eukaryotic cells, where is the transcription of DNA primarily carried out?A. CytoplasmB. MitochondriaC. NucleusD. Ribosomes4. What is the basic unit of heredity in all living organisms?A. GeneB. ChromosomeC. DNA moleculeD. Protein5. The term "genome" refers to:A. The complete set of genes of an organismB. The entire DNA of an organismC. The sum of all the proteins in an organismD. The collection of all the cells in an organism6. Which of the following is a method of genetic engineering?A. CrossbreedingB. CloningC. CRISPR-Cas9D. Natural selection7. What is the role of tRNA in protein synthesis?A. To provide the energy for the processB. To carry specific amino acids to the ribosomeC. To serve as the template for protein synthesisD. To catalyze the formation of peptide bonds8. The Hardy-Weinberg principle states that the allele frequencies in a population will remain constant in the absence of:A. MigrationB. Genetic driftC. Natural selectionD. All of the above9. Which of the following is not a type of mutation?A. DeletionB. InsertionC. TranslocationD. Translation10. The process of photosynthesis primarily occurs in the:A. Cell wallB. CytoplasmC. ChloroplastsD. Nucleus二、填空题（每空1分，共10分）1. The chemical structure of DNA is a double ________ helix.2. The process by which a fertilized egg develops into a mature organism is called ________.3. In genetics, the term "dominant" refers to an allele that expresses its effect when ________.4. The scientific name for a species is composed of two parts: the genus name and the ________ name.5. The primary function of the Golgi apparatus is to ________, modify, and package proteins for secretion or delivery toother organelles.三、简答题（每题10分，共20分）1. Explain the difference between prokaryotic and eukaryotic cells.2. Describe the process of mitosis and its significance incell division.四、翻译题（每题15分，共30分）1. Translate the following sentence into English:"基因编辑技术，如CRISPR-Cas9，为研究和治疗遗传性疾病提供了新的可能性。
小学上册第六次英语第1单元期末试卷
小学上册英语第1单元期末试卷考试时间：90分钟（总分:100）B卷一、综合题(共计100题共100分)1. landfill) is where waste is buried. 填空题：The ____2. 填空题：The park is ________ (热闹的).3. 选择题：Which insect can create honey?A. AntB. BeeC. ButterflyD. Mosquito答案: B4. 选择题：What is the process of water changing to vapor called?A. EvaporationB. CondensationC. PrecipitationD. Freezing5. 选择题：What color are strawberries?A. BlueB. YellowC. RedD. Green6. 听力题：A ____ can often be seen in gardens looking for food.7. 听力题：A _______ is a type of plant that grows in the desert.8. 听力题：A flamingo gets its pink color from its ______.9. 选择题：Which of these is a type of fruit?A. LettuceB. CarrotC. TomatoD. Spinach答案:C10. 选择题：What do we call a person who studies the effects of climate change on species?A. EcologistB. BiologistC. ConservationistD. Environmental Scientist答案: A11. 选择题：What is the name of the fairy tale character who had long hair?A. Snow WhiteB. CinderellaC. RapunzelD. Sleeping Beauty答案:C12. 选择题：What is the name of the famous explorer who sailed the Pacific Ocean?A. Ferdinand MagellanB. Christopher ColumbusC. Vasco da GamaD. John Cabot答案: A13. 听力题：Fossils can provide information about past ______ environments.14. 填空题：I got a new ________ for my birthday.15. 填空题：My dog loves to dig ______ (洞) in the backyard.16. 选择题：What is the primary ingredient in hummus?B. ChickpeasC. PeasD. Beans答案:B17. 选择题：What is the main organ in the human body that pumps blood?A. BrainB. LungsC. HeartD. Liver答案: C18. 填空题：The butterfly rests on a ______ (花).19. ng Rebellion was a massive civil war in ________ (中国). 填空题：The Taj20. 听力题：I have a _______ (surprise) for you.21. 填空题：My __________ (玩具名) is a great __________ (名词) for learning.22. 填空题：I like to watch the birds in the ______.23. 选择题：What do we call the process of a caterpillar becoming a butterfly?A. MetamorphosisB. GrowthC. ChangeD. Transformation答案: A24. 填空题：I love to pick ______ (水果) in the summer. They are so ______ (美味).25. 选择题：What is the capital city of Malaysia?a. Kuala Lumpurb. Penangc. Johor Bahru答案:a26. 填空题：My favorite superhero _________ (玩偶) has a cool _________ (披风).27. 填空题：I love to feel the __________ on my face during a sunny day. (微风)28. 填空题：The ________ is one of the Seven Wonders of the Ancient World.29. 听力题：The __________ is the measure of how much matter is in a given volume.30. 选择题：How many players are on a soccer team?A. ElevenB. TenC. NineD. Twelve31. 听力题：A __________ is a measure of how fast a reaction occurs.32. 选择题：What is the capital of Belize?a. Belmopanb. Belize Cityc. San Ignaciod. Corozal答案:a33. 听力题：An ant is an example of a __________ insect.34. 选择题：What is the capital of Finland?A. HelsinkiB. OsloC. TallinnD. Riga答案:A35. 填空题：The __________ (种植者) planted seeds in rows.What do you call the line that separates two countries?A. BoundaryB. BorderC. FrontierD. Division37. 填空题：I found a ________ in the grass.38. 选择题：What is the capital of Kyrgyzstan?A. BishkekB. OshC. Jalal-AbadD. Tokmok39. 听力题：The Earth’s crust is made up of several large ______.40. 选择题：What do we call the act of trying out new things?A. ExperimentingB. TestingC. SamplingD. All of the Above答案：D41. 选择题：Which word means "to look at something closely"?A. ObserveB. IgnoreC. ForgetD. Understand42. 填空题：The __________ (历史的启发) can motivate change.43. 填空题：Turtles can withdraw into their ______ (壳).44. 填空题：My mom works as a ______ (我妈妈工作是) teacher.45. 听力题：The Orion constellation is best seen in ______._____ (农田) are filled with crops.47. 听力题：I have a _____ (pen).48. 选择题：What do we call the small pieces of glass used for decoration?A. MarbleB. BeadsC. GemsD. Mosaic答案:D49. 选择题：What do we call a scientist who studies marine life?a. Marine biologistb. Oceanographerc. Aquatic ecologistd. Ichthyologist答案:a50. 选择题：What is the name of the famous mountain in North America?A. Mount DenaliB. Mount RushmoreC. Mount RainierD. Mount Whitney答案: A. Mount Denali51. 选择题：Which of these is NOT a primary color?A. RedB. BlueC. GreenD. Yellow52. 填空题：A _____ (海豚) can leap out of the water gracefully.53. 选择题：What is 2 + 2?A. 3B. 4C. 5D. 6答案:B54. 填空题：I can jump very ______.55. 听力题：She _____ (has/have) a cute puppy.56. 选择题：What is the primary color of grass?A. RedB. YellowC. BlueD. Green答案: D57. 填空题：The first successful vaccine was developed by _______. (詹纳)58. 听力题：They are ___ (happy/sad) about the trip.59. 选择题：Which animal is known for being very slow?A. RabbitB. TurtleC. CheetahD. Kangaroo答案:B60. 填空题：He is very _____ (善于沟通) in meetings.61. 选择题：What is the name of the famous clock tower in London?A. Big BenB. Eiffel TowerC. Statue of LibertyD. Colosseum答案: A62. 选择题：What is the capital of Sweden?A. StockholmB. GothenburgD. Uppsala答案: A63. 听力题：I like to eat _____ (苹果).64. 听力题：I can ________ (skate) on rollerblades.65. 听力题：I like to ________ my homework.66. 听力题：A _____ is a phenomenon where a star dimples.67. 选择题：What is the name of the famous artist known for his "The Kiss"?A. Gustav KlimtB. Edvard MunchC. Vincent van GoghD. Claude Monet答案: A68. 选择题：What is the capital city of Portugal?A. LisbonB. PortoC. FaroD. Madeira69. 听力题：The chemical formula for sodium phosphate is _____.70. 听力题：I like to ________ cartoons.71. 填空题：A tortoise can retract its head into its ______ (壳).72. community project) addresses local needs. 填空题：The ____73. 选择题：What do we call the study of how living things interact with each other and their environment?B. BiologyC. ZoologyD. Botany答案: A. Ecology74. 选择题：Which fruit is known for having seeds on the outside?A. RaspberryB. StrawberryC. BlueberryD. Blackberry75. 听力题：The __________ is a well-known landmark of freedom.76. 填空题：I love to draw pictures of ________.77. 听力题：I like to ______ stories about adventures. (read)78. 填空题：The garden is vibrant with ______.79. 选择题：What do you call a person who studies insects?A. EntomologistB. BiologistC. ZoologistD. Botanist答案: A80. 听力题：I see a rainbow after the ______ (storm).81. 听力题：The cat is _____ (black).82. 听力题：A __________ is formed by the accumulation of minerals over time.83. 听力题：My favorite color is _______ (blue).84. 听力题：A ____ has a spiny back and can curl into a ball for protection.85. 填空题：The first successful test of a nuclear bomb occurred in ________ (1945).86. 听力题：The body of water located between Africa and the Arabian Peninsula is the __________ Sea.87. 填空题：The goldfish swims in circles in its _________. (鱼缸)88. 听力填空题：I believe in the power of friendship. Friends support each other and share good times. I feel lucky to have a friend like __________ who always makes me smile.89. 听力题：The city of Vilnius is the capital of _______.90. 选择题：Which season comes after summer?A. WinterB. FallC. SpringD. Rainy答案:B91. 填空题：The __________ is a famous landmark in Beijing. (天坛)92. 听力题：I see a _____ (dragon) in the story.93. 填空题：My dad helps me fix my ____.94. 选择题：What is the opposite of "hot"?A. ColdB. WarmC. CoolD. Boiling答案: A95. 填空题：My ________ (玩具) can be used for storytelling.96. 听力题：The _____ (garden) is full of plants.97. 填空题：Koalas eat _______ (桉树叶).98. 填空题：I enjoy _______ (与家人一起)庆祝节日.99. 选择题：What do you call the process of a plant producing seeds?A. GerminationB. PollinationC. FertilizationD. Seed Dispersal答案: B100. 听力题：The __________ is located at the southernmost point of South America.。
环状和链状烯烃的硅氢加成研究
收稿日期:1999-09-22作者简介:盛晓莉(1977-),女,硕士生1 文章编号:1006-0464(2000)01-0131-05环状和链状烯烃的硅氢加成研究盛晓莉 李凤仪 杨 健(南昌大学应用化学研究所,江西南昌 330047)摘 要:用同一种催化剂合成了含环己基有机硅化合物和含乙烯基有机硅化合和物,并比较了催化合成这两种类型的有机硅化合物对催化剂的活化方式、反应温度控制的不同,发现环状烯烃比链状烯烃在催化加成上有更高的要求。
前者必须在有氧的参与下才能有效地控制反应,而后者无须氧的介入,从而对这两种反应机制进行了初探。
关键词:环己烯;乙烯;催化加成;三氯硅烷;甲基二氯硅烷中图分类号:O643132 文献标识码:A以环己烯和含氢氯硅烷为原料合成的环己基氯硅烷是一种重要的硅烷偶联剂,又是合成有机硅聚合物、有机硅氧聚合物的中间体〔1〕,同时又可用作光电材料,如电致感光的光感受器中的光敏感层〔2〕,使得光感受器具有高的敏感性,好的抗磨性,好的胶粘性以及重复使用性。
它还可用作印刷术中的防染剂〔3〕,太阳能电池中的感光乳剂胶层〔4〕等。
以乙炔和三氯硅烷为原料合成的乙烯基三氯硅烷也是一种重要的硅烷偶联剂,它不仅可以适用于作玻璃纤维表面处理和增强塑料层压品的处理剂,也可用于含氯树脂的改性和橡胶工业的偶联剂,同时又是工业中的基本单体,以其为单体可制得一系列与之相关的下游产品。
以乙炔和甲基二氯硅烷为原料合成的甲基乙烯基二氯硅烷是高温硫化硅橡胶中的重要单体。
我们所采用的硅氢加成法使用的是均相催化剂,其具有催化活性高、反应条件温和的特点。
通过对这两种不同类型烯烃的加成反应的比较,对其反应机理和影响因素进行了考察。
1 实验部分111 主要实验原料环己烯(化学纯),其它原料乙炔,三氯硅烷,甲基二氯硅烷使用前均经过处理。
112 催化剂的制备取一定量的氯铂酸制成络合型催化剂,其浓度为0.0386mol/L 。
113 硅氢加成法制备环己基氯硅烷的实验在100mL 四口烧瓶中加入一定量催化剂和一定量溶剂及环己烯,用鼓泡带入氯硅烷进四口烧瓶,同时通入一定流速的空气。
宁波2024年统编版小学P卷英语第2单元真题(含答案)
宁波2024年统编版小学英语第2单元真题(含答案)考试时间：80分钟（总分:120）A卷一、综合题(共计100题共100分)1. 选择题：What is the capital of Papua New Guinea?A. Port MoresbyB. LaeC. Mount HagenD. Madang答案:A2. 选择题：What is the name of the famous singer known as "The King of Pop"?A. Elvis PresleyB. Michael JacksonC. PrinceD. Frank Sinatra答案:B3. 听力题：The process of combining substances to form a new substance is called _____.4. 选择题：What is the capital of Colombia?A. BogotáB. MedellínC. CaliD. Cartagena5. 听力题：The chemical formula for acetic acid is ________.6. 听力题：The chemical formula for arachidic acid is ______.What do we call the solid part of the Earth?A. AtmosphereB. LithosphereC. HydrosphereD. Biosphere8. 听力题：The kitten is ______ on the windowsill. (resting)9. 听力填空题：I love exploring new places. Every summer, my family goes on a trip to __________. We visit museums, parks, and try local foods.10. 填空题：Every morning, I ______ (吃) breakfast with my family.11. 听力题：The element with atomic number is __________.12. 听力题：The ______ shares her passions with others.13. 选择题：What is the name of the tool used to measure temperature?A. BarometerB. ThermometerC. SpeedometerD. Altimeter答案:B14. 选择题：What sound does a dog make?A. MeowB. MooC. BarkD. Quack15. 选择题：What is the capital of France?A. RomeB. ParisC. BerlinD. Madrid答案:BWhich is the tallest mountain in the world?A. K2B. KilimanjaroC. EverestD. Fuji答案:C17. 听力题：I can ___ (count) to ten.18. 选择题：What do we call the act of breathing in?A. ExpirationB. InspirationC. ExhalationD. Respiration答案:B19. 填空题：The puppy learns tricks from its _________. (主人)20. 填空题：The rabbit’s nose _______ (快速地) twitches.21. 选择题：What is the chemical symbol for water?A. O2B. H2OC. CO2D. NaCl22. 选择题：What do we call a place where animals are kept for public display?A. FarmB. ZooC. ParkD. Garden答案: B23. 填空题：I like to collect ________ (玩偶) from different places.24. 填空题：The _______ (The Spanish Conquest) of the Aztecs led to Spanish colonization.The __________ (珍稀动物) need protection from extinction.26. 听力题：Reactions that absorb energy from the surroundings are called ________ reactions.27. 选择题：What color is a typical lemon?A. GreenB. YellowC. RedD. Orange答案: B28. 填空题：I have a _____ (色笔) that I use to draw my favorite animals. 我有一支彩色笔，用来画我最喜欢的动物。
成都2024年小学三年级I卷英语第四单元全练全测(含答案)
成都2024年小学三年级英语第四单元全练全测(含答案)考试时间：80分钟（总分:120）A卷考试人：_________题号一二三四五总分得分一、综合题(共计100题)1、听力题：My mom is a ______. She takes care of our family.2、填空题：A tarantula's silk is used to create a ______ (网).3、听力题：Electromagnetic radiation includes visible light and ______.4、What is the name of the holiday celebrated on July 4th in the USA?A. ThanksgivingB. Independence DayC. ChristmasD. Memorial Day答案:B5、听力题：The chemical formula for sodium citrate is __________.6、听力题：A physical change does not alter the ______ of a substance.7、听力题：My mom loves to decorate our ____ (home).8、What do you call a person who studies music?A. MusicianB. ComposerC. MusicologistD. All of the above答案:D9、听力题：The chemical symbol for calcium is ______.10、填空题：My grandma makes the best ______ (饼干). I love to help her in the ______ (厨房).11、填空题：Many people enjoy ______ (种植) flowers in their gardens.12、填空题：The __________ (探险故事) inspire many people.13、填空题：_____ (environment) affects plant health.14、填空题：I like to collect ________ (古董) and learn their history.15、填空题：They are ______ (兄弟) and sisters.16、What do you call a young whale?A. CalfB. PupC. KitD. Lamb17、听力题：I see a ___ at the store. (toy)18、填空题：The _____ (狮子) rules over the African savanna.19、What do you call a baby chicken?A. DucklingB. GoslingC. ChickD. Puppy20、What do we call the color of the sun?A. BlueB. YellowC. GreenD. Red答案: B. Yellow21、What do we call the study of plants?A. BiologyB. BotanyC. ZoologyD. Ecology答案:B. Botany22、选择题：What instrument is used to measure temperature?A. BarometerB. ThermometerC. SpeedometerD. Altimeter23、填空题：A _____ (生态旅游) can focus on plant life.24、填空题：A lemur has big ______ (眼睛) and a long tail.25、How many days are there in a week?A. FiveB. SixC. SevenD. Eight答案: C. Seven26、听力题：A ______ can develop into various forms.27、听力题：The ______ teaches us about nutrition.28、Which fruit is yellow and curved?A. AppleB. BananaC. CherryD. Grape29、What do you call a group of musicians?A. BandB. OrchestraC. EnsembleD. All of the above30、听力题：I enjoy _____ (reading/writing) stories.31、听力题：The element with atomic number is __________.32、听力题：The process of changing from a liquid to a gas is called ______.33、填空题：A manatee is known as a sea ______ (牛).34、选择题：What is the main language spoken in Brazil?A. SpanishB. PortugueseC. FrenchD. English35、What is the name of the famous bear that loves honey?A. Paddington BearB. Winnie-the-PoohC. Yogi BearD. Baloo答案: B. Winnie-the-Pooh36、What do we use to take pictures?A. CameraB. PhoneC. ComputerD. Tablet37、填空题：I enjoy painting ______ pictures.38、What sweet food is made from cocoa beans?A. CandyB. ChocolateC. CakeD. Ice cream答案:B39、听力题：Saturn's moons include Titan and ______.40、What do we call a person who travels to space?A. AstronautB. PilotC. ScientistD. Engineer答案:A41、What is the capital of the USA?A. New YorkB. Washington D.C.C. Los AngelesD. Chicago答案:B42、填空题：I have a pet ______ that is very friendly.43、听力题：Kites fly high due to _______ and lift.44、选择题：What do we call the soil used to grow plants?A. ClayB. DirtC. CompostD. Potting soil45、What do we call the study of the Earth?A. BiologyB. GeographyC. AstronomyD. Physics答案:B46、听力题：The boy is learning to ________.47、Which animal is known as the "King of the Jungle"?A. ElephantB. LionC. TigerD. Bear48、听力题：She has a nice ________.49、What do we call the line around the Earth?A. EquatorB. LatitudeC. LongitudeD. Meridian答案：A50、填空题：My brother has a passion for __________ (动物保护).51、填空题：My aunt, ______ (我的阿姨), is an excellent baker.52、How many zeros are in one thousand?A. 2B. 3C. 4D. 5答案:B. 353、What do you call a baby goat?A. CalfB. KidC. LambD. Pup54、听力题：The process of fermentation is used to produce _______.55、听力题：The cat lounges in a _____ sunny spot.56、填空题：My family enjoys going to the ____.57、What is the opposite of 'up'?A. DownB. LeftC. RightD. Forward58、听力题：A ____ is a friendly pet that loves being around people.59、听力题：The chemical formula for calcium chloride is ______.A __________ is a creature that can glow in the dark.61、听力题：A __________ is known for its long ears and strong legs.62、听力题：She is a good ________.63、What is the main language spoken in the United States?A. SpanishB. FrenchC. EnglishD. Chinese答案: C. English64、How many continents are there in Africa?A. 5B. 6C. 7D. 865、What do we call a person who designs clothes?A. TailorB. Fashion designerC. ModelD. Stylist答案:B66、填空题：My favorite book is about a __________ (英雄) who saves the day.67、填空题：________ (植物适应性策略) are employed for success.68、听力题：A solution that has a high concentration of ions is called a ______ solution.69、填空题：In _____ (印度), there are many active volcanoes.70、填空题：The _____ (种子) of a plant can be found inside its fruit.71、听力题：The bird is ___ in the sky. (soaring)We visited the _____ (博物馆).73、选择题：Which device do we use to call someone?A. TelevisionB. TelephoneC. RadioD. Computer74、选择题：What is the smallest continent?A. AfricaB. EuropeC. AustraliaD. Asia75、听力题：I need to _____ (buy/sell) groceries.76、填空题：Certain plants are capable of surviving long periods of ______ without water.(某些植物能够在缺水的条件下存活很长时间。
水相条件下烯烃的选择性氧化
水相条件下烯烃的选择性氧化崔晓雪;杨静;郑永丽;曹卫忠【摘要】A series of olefins were oxidized using H2O2,V2O5,Aliquat 336and water.The influence of catalyst,dosage of PTC and hydrogen peroxide were discussed.The most optimum condition was as follows,substrate ∶V2O5∶H2O2∶ Aliquat336 =1∶ 0.04∶ 2.5∶ 0.15.The experimental resultsof oxidation of different olefins showed that the electron rich olefins could be selectively oxidized in the system built by H2O2,V2O5,Aliquat 336 and water.%以水为媒介,甲基三辛基氯化铵(Aliquat 336)为相转移催化剂,五氧化二钒(V2O5)为催化剂,用双氧水(H2O2)对烯烃进行氧化,讨论了V2O5、Aliquat 336和H2O2的用量对氧化反应的影响,确定了水相氧化体系的最优反应比,即烯烃:H2O2∶ V2O5:甲基三辛基氯化铵=1∶2.5∶0.04∶0.15.通过对不同烯烃的氧化实验,证明该反应体系具有选择性,即可以选择性氧化富电子的烯烃.【期刊名称】《化学工程师》【年(卷),期】2017(031)001【总页数】4页(P75-78)【关键词】烯烃;选择性氧化;水相;五氧化二钒;双氧水【作者】崔晓雪;杨静;郑永丽;曹卫忠【作者单位】天津渤海职业技术学院,天津300402;天津渤海职业技术学院,天津300402;天津渤海职业技术学院,天津300402;天津渤海职业技术学院,天津300402【正文语种】中文【中图分类】O621.3烯烃的氧化反应是化学工业中重要的反应之一，其氧化产物环氧化合物、醛、酮、酸等是化工生产中重要的原料、涂料以及重要的有机合成中间体。