Effect of magnetic field on poroelastic bone model for internal remodeling
静磁场对细胞内蛋白质影响研究进展
Industry Review 行业综述
静磁场对细胞内蛋白质影响研究进展
Effect of Static Magnetic Field on Intracellular Protein
◎ 赵 勇 1,郭利芳 1,盛占武 2 (1. 海南职业技术学院,海南 海口 570216; 2. 中国热带农业科学院海口实验站,海南 海口 570102) Zhao Yong1, Guo Lifang1, Sheng Zhanwu2 (1.Hainan College of Vocation and Technique, Haikou 570216, China; 2.Haikou Experimental Station, Chinese Academy of Tropical Agricultural Sciences,
1 静磁场对生物膜离子通道的影响
科学家们在对生物电产生机制的研究中观察到生 物膜对离子通透性的变化。20 世纪 50 年代,英国生 物物理学家 Hodgkin 等人通过大量研究后提出离子通
XIANDAISHIPIN 现代食品 / 01
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Jovanova-Nesic 等 人 [9] 采 用 AlCl3 处 理 大 鼠 大 脑 核区神经细胞,降低 Na/K 泵的活性,再用 60 mT 磁 场处理,结果发现可增加 Na/K 泵的活性。Rosen[10] 研 究发现在增殖的 GH3 细胞中电压激活的 Na+ 通道经 125 mT 的磁场作用后缩减。并非所有离子的运输都会
细胞、分子等多个层面开展。目前,细胞内蛋白质分 子受静磁场的影响多表现在细胞膜的离子通道和细胞 内的酶蛋白中。静磁场对生物系统的影响作为一个重 要的研究领域,多年来受到国内外学者的广泛关注。 国内外关于静磁场的生物学效应已有大量研究,证据 表明静磁场对很多生物体和生物组织均存在影响。研 究静磁场作用下生物有机体的响应机制,对深入了解 静磁场的生物学效应具有重要意义。
脉冲电磁场对骨质疏松的生物效应_关志成
T he prev entive ex periments demonstrate that the co rrected bone mineral density is hig her than that o f O VX g roup (P <0. 05). I n the further studies, the serum bo ne marker and biomechanics pro per ties w ill be te sted. Based o n the efficacy of cellular level and animal mo del, the effects o f pulsed electro magnetic fields w ere inv estiga ted , the bone mineral density w as improved and the pain level was alleviated significantly after treatment. Consequently , it is concluded
松的防治中发挥重要作用 。
关键词 :脉冲电磁场 ;骨质疏松 ;机理 ;成骨细胞 ;动物模型 ;临床研究
磁学 径向克尔 英文 kerr effect
IntroductionThe Kerr effect, also known as the magneto-optic Kerr effect (MOKE), is a phenomenon that manifests the interaction between light and magnetic fields in a material. It is named after its discoverer, John Kerr, who observed this effect in 1877. The radial Kerr effect, specifically, refers to the variation in polarization state of light upon reflection from a magnetized surface, where the change occurs radially with respect to the magnetization direction. This unique aspect of the Kerr effect has significant implications in various scientific disciplines, including condensed matter physics, materials science, and optoelectronics. This paper presents a comprehensive, multifaceted analysis of the radial Kerr effect, delving into its underlying principles, experimental techniques, applications, and ongoing research directions.I. Theoretical Foundations of the Radial Kerr EffectA. Basic PrinciplesThe radial Kerr effect arises due to the anisotropic nature of the refractive index of a ferromagnetic or ferrimagnetic material when subjected to an external magnetic field. When linearly polarized light impinges on such a magnetized surface, the reflected beam experiences a change in its polarization state, which is characterized by a rotation of the plane of polarization and/or a change in ellipticity. This alteration is radially dependent on the orientation of the magnetization vector relative to the incident light's plane of incidence. The radial Kerr effect is fundamentally governed by the Faraday-Kerr law, which describes the relationship between the change in polarization angle (ΔθK) and the applied magnetic field (H):ΔθK = nHKVwhere n is the sample's refractive index, H is the magnetic field strength, K is the Kerr constant, and V is the Verdet constant, which depends on the wavelength of the incident light and the magnetic properties of the material.B. Microscopic MechanismsAt the microscopic level, the radial Kerr effect can be attributed to twoprimary mechanisms: the spin-orbit interaction and the exchange interaction. The spin-orbit interaction arises from the coupling between the electron's spin and its orbital motion in the presence of an electric field gradient, leading to a magnetic-field-dependent modification of the electron density distribution and, consequently, the refractive index. The exchange interaction, on the other hand, influences the Kerr effect through its role in determining the magnetic structure and the alignment of magnetic moments within the material.C. Material DependenceThe magnitude and sign of the radial Kerr effect are highly dependent on the magnetic and optical properties of the material under investigation. Ferromagnetic and ferrimagnetic materials generally exhibit larger Kerr rotations due to their strong net magnetization. Additionally, the effect is sensitive to factors such as crystal structure, chemical composition, and doping levels, making it a valuable tool for studying the magnetic and electronic structure of complex materials.II. Experimental Techniques for Measuring the Radial Kerr EffectA. MOKE SetupA typical MOKE setup consists of a light source, polarizers, a magnetized sample, and a detector. In the case of radial Kerr measurements, the sample is usually magnetized along a radial direction, and the incident light is either p-polarized (electric field parallel to the plane of incidence) or s-polarized (electric field perpendicular to the plane of incidence). By monitoring the change in the polarization state of the reflected light as a function of the applied magnetic field, the radial Kerr effect can be quantified.B. Advanced MOKE TechniquesSeveral advanced MOKE techniques have been developed to enhance the sensitivity and specificity of radial Kerr effect measurements. These include polar MOKE, longitudinal MOKE, and polarizing neutron reflectometry, each tailored to probe different aspects of the magnetic structure and dynamics. Moreover, time-resolved MOKE setups enable the study of ultrafast magneticphenomena, such as spin dynamics and all-optical switching, by employing pulsed laser sources and high-speed detection systems.III. Applications of the Radial Kerr EffectA. Magnetic Domain Imaging and CharacterizationThe radial Kerr effect plays a crucial role in visualizing and analyzing magnetic domains in ferromagnetic and ferrimagnetic materials. By raster-scanning a focused laser beam over the sample surface while monitoring the Kerr signal, high-resolution maps of domain patterns, domain wall structures, and magnetic domain evolution can be obtained. This information is vital for understanding the fundamental mechanisms governing magnetic behavior and optimizing the performance of magnetic devices.B. Magnetometry and SensingDue to its sensitivity to both the magnitude and direction of the magnetic field, the radial Kerr effect finds applications in magnetometry and sensing technologies. MOKE-based sensors offer high spatial resolution, non-destructive testing capabilities, and compatibility with various sample geometries, making them suitable for applications ranging from magnetic storage media characterization to biomedical imaging.C. Spintronics and MagnonicsThe radial Kerr effect is instrumental in investigating spintronic and magnonic phenomena, where the manipulation and control of spin degrees of freedom in solids are exploited for novel device concepts. For instance, it can be used to study spin-wave propagation, spin-transfer torque effects, and all-optical magnetic switching, which are key elements in the development of spintronic memory, logic devices, and magnonic circuits.IV. Current Research Directions and Future PerspectivesA. Advanced Materials and NanostructuresOngoing research in the field focuses on exploring the radial Kerr effect in novel magnetic materials, such as multiferroics, topological magnets, and magnetic thin films and nanostructures. These studies aim to uncover newmagnetooptical phenomena, understand the interplay between magnetic, electric, and structural order parameters, and develop materials with tailored Kerr responses for next-generation optoelectronic and spintronic applications.B. Ultrafast Magnetism and Spin DynamicsThe advent of femtosecond laser technology has enabled researchers to investigate the radial Kerr effect on ultrafast timescales, revealing fascinating insights into the fundamental processes governing magnetic relaxation, spin precession, and all-optical manipulation of magnetic order. Future work in this area promises to deepen our understanding of ultrafast magnetism and pave the way for the development of ultrafast magnetic switches and memories.C. Quantum Information ProcessingRecent studies have demonstrated the potential of the radial Kerr effect in quantum information processing applications. For example, the manipulation of single spins in solid-state systems using the radial Kerr effect could lead to the realization of scalable, robust quantum bits (qubits) and quantum communication protocols. Further exploration in this direction may open up new avenues for quantum computing and cryptography.ConclusionThe radial Kerr effect, a manifestation of the intricate interplay between light and magnetism, offers a powerful and versatile platform for probing the magnetic properties and dynamics of materials. Its profound impact on various scientific disciplines, coupled with ongoing advancements in experimental techniques and materials engineering, underscores the continued importance of this phenomenon in shaping our understanding of magnetism and driving technological innovations in optoelectronics, spintronics, and quantum information processing. As research in these fields progresses, the radial Kerr effect will undoubtedly continue to serve as a cornerstone for unraveling the mysteries of magnetic materials and harnessing their potential for transformative technologies.。
有研粉末新材料股份有限公司上交所科创板上市
• 56 •粉末冶金工业第31卷•行业动灸*有研粉末新材料股份有限公司上交所科创板上市2021年3月17日,有研粉末新材料股份有限公司正式在上海证券交易所科创板上市,股票代码为 688456=粉末冶金产业技术创新战略联盟(CPMA)理事长、中国钢研科技集团有限公司董事长张少明,联盟副理 事长、有研粉末新材料股份有限公司董事长汪礼敏出席上市仪式。
出席上市仪式的还有有研科技集团有限 公司的领导,联盟副理事长李普明、申承秀,联盟专家委副主任曲选辉,联盟副秘书长曹阳以及联盟理事汪 志荣、薛志生等领导和专家。
有研粉末新材料股份有限公司以先进有色金属粉体材料的设计、研发、生产和销售为主营业务,主要产 品包括铜基金属粉体材料、微电子锡基焊粉材料和3D打印粉体材料等。
此次1PO,有研粉末新材料股份有 限公司拟将4.05亿元募集资金用于有研粉末新材料股份有限公司科技创新中心建设项目、新建粉体材料基 地建设项目、泰国产业基地建设项目以及补充流动资金。
有研粉末新材料股份有限公司己经掌握众多与有色金属粉体材料制备和应用相关的核心技术,目前生 产经营应用的主要核心技术有:球形金属粉体材料制备技术;高品质电解铜粉绿色制备技术;系列无铅环保 微电子焊粉制备及材料设计技术;扩散/复合粉体材料均匀化制备技术;超细金属粉体材料制备技术;3D打 印粉体材料制备技术;高性能粉末冶金中空凸轮轴制备技术。
有研粉末新材料股份有限公司铜基金属粉体材料广泛应用于粉末冶金、超硬工具、摩擦材料、电碳制 品、电工合金等领域,主要客户包括汽车零部件供应商辉门集团,赫格纳斯集团,东睦股份,博深股份,天宜 上佳,神奇电碳集团等;微电子锡基焊粉材料专门用于微电子封装领域,主要客户包括确信爱法、铟泰科技、弘辉电子等世界知名锡焊料生产商。
有研粉末新材料股份有限公司主营产品为铜基金属粉体材料、微电子锡基焊粉材料和3D打印粉体材 料。
2020年上半年,有研粉末新材料股份有限公司以上主营业务收入分别为4.80亿元、丨.77亿元、59.29万元,占比分别为65.16%、24.03%、0.08%,铜基金属粉体材料占比超50%。
磁场流速对传感器用Cu电极电解过程及质量的影响
第31卷第2期 202丨年4月粉宋冶全工业P O W D E R M E T A L L U R G Y I N D U S T R YVol. 31,No.2,p52-56Apr. 2021DOI : 10.13228/j.boyuan.issn 1006-6543.20200137磁场流速对传感器用C u电极电解过程及质量的影响孙娟',孙栗2,金晗3(1.河南科技职业大学,河南周口466000; 2.国网浙江海宁市供电公司,浙江海宁314400;3.中原工学院能源与环境学院,河南郑州460000)摘要:在电解工艺制备铜的过程中加入磁场以达到协同强化效果,分析了磁场流速对传感器用C u电极电解过程及质量的影响。
结果表明:施加磁场后,形成了更复杂的铜电解反应。
当提高磁场流速后,铜阳极质量损失减小,最大阴极析出量出现于流速为0.25 m/s的情况下。
磁场流速对C u电极电解阶段的杂质离子产生着显著影响。
受到磁场作用后,杂质离子浓度减小,实际效果受到此磁场取向与流速的共同作用。
处于0.25 m/s磁场流速下,能够获得最大的阴极析出速率,从而减小电解液内的杂质离子浓度并降低铜损失。
处于垂直磁场中,在0〜0.75 m/s范围的电解液黏度基本恒定,并在0.25 m/s时达到最小值。
垂直磁场可以对电子传输发挥抑制作用,增强扩散效果。
随着流速的增大,阻碍了 Cir1扩散过程,在0.25 m/s速率下获得最大阴极析出量。
关键词:磁化电解;强磁场;铜电解;表面质量文献标志码:A 文章编号:1006-6543(2021)02-0052-05Effect of magnetic field velocity on electrolysis process and quality of Cuelectrode used in sensorSUN Juan1,SUN Li2,JIN Han3(1. Henan Vocational University of Science and Technology, Zhoukou 466000, China; 2. State Grid HainingPower Supply Company, Haining 314400, China; 3. School of Energy and Environment, Zhongyuan Universityof Technology, Zhengzhou 460000, China)A bstract:The effect of magnetic field velocity on the electrolytic process and the quality of Cu electrode used inthe sensor was analyzed.The results show that a more complex copper electrolysis reaction is formed by applying amagnetic field.After increasing the magnetic field velocity, the mass loss of copper anode decreased, and the maximum cathode precipitation appeared at the flow rate of 0.25 m/s.The magnetic field velocity has a significant effecton the impurity ions in Cu electrode electrolysis stage.The concentration of impurity ions decreases after the magnetic field is applied, and the actual effect is influenced by the magnetic field orientation and the flow velocity.Atthe magnetic field velocity of 0.25 m/s, the maximum cathode precipitation rate can be obtained, thus reducing theconcentration of impurity ions in the electrolyte and reducing the copper loss.In the vertical magnetic field, the electrolyte viscosity in the range of 0-0.75 m/s is basically constant, and reaches the minimum value at 0.25 m/s.Vertical magnetic field can inhibit electron transport and enhance diffusion.With the increase of flow rate, C u2'diffusionprocess was hindered, and the maximum cathode precipitation was obtained at the rate of 0.25 m/s.Key w ords:magnetization electrolysis; strong magnetic field; copper electrolysis; surface quality 现阶段,电解技术己经成为一种非常广泛的铜 制备工艺。
介绍地球磁场的作文英文
介绍地球磁场的作文英文英文:The Earth's magnetic field is a fascinating and essential aspect of our planet. It plays a crucial role in protecting the Earth from harmful solar winds and cosmic radiation. The magnetic field is generated by the movement of molten iron and nickel in the Earth's outer core. This movement creates electric currents, which in turn produce a magnetic field. This field extends from the Earth'sinterior out into space and is often compared to a giant bar magnet.The Earth's magnetic field has a significant impact on our daily lives, although we may not always be aware of it. For example, it is the reason why a compass always points north. The magnetic field also affects the behavior of migratory birds and certain animal species that use it for navigation. Furthermore, it helps scientists understand the geological history of the Earth, as the magnetic mineralsin rocks align themselves with the Earth's magnetic fieldat the time of their formation.The magnetic field is not static and has undergone numerous reversals throughout Earth's history. These reversals, known as geomagnetic reversals, occur when the magnetic north and south poles switch places. This phenomenon has been studied by scientists, and the evidence of these reversals can be found in the ocean floor and in rocks.中文:地球的磁场是我们星球上一个迷人且至关重要的方面。
地球磁场对大脑的影响
地球磁场对大脑的影响英文回答:The influence of the Earth's magnetic field on the brain is a fascinating topic that has been studied by scientists for many years. While the exact mechanisms are not fully understood, there is evidence to suggest that the magnetic field can have an impact on brain function and behavior.One way in which the Earth's magnetic field may affect the brain is through its influence on the production and release of certain neurotransmitters. Neurotransmitters are chemicals that allow nerve cells to communicate with each other, and they play a crucial role in regulating mood, cognition, and other brain functions. Studies have shown that exposure to magnetic fields can alter the levels of certain neurotransmitters, such as serotonin and dopamine, in the brain. These changes in neurotransmitter levels can in turn affect mood and behavior.For example, research has found a link between magnetic field exposure and changes in sleep patterns. The Earth's magnetic field is known to fluctuate throughout the day, and these fluctuations have been shown to affect the production of melatonin, a hormone that regulates sleep-wake cycles. When the magnetic field is disrupted, it can disrupt melatonin production, leading to sleep disturbances and other sleep-related issues.In addition to neurotransmitter levels, the Earth's magnetic field may also influence the brain through its impact on electrical activity. The brain generateselectrical signals that are essential for communication between neurons. It has been suggested that magnetic fields can influence these electrical signals, potentiallyaltering brain function.One study, for instance, found that exposure to a magnetic field can affect the brain's response to visual stimuli. Participants in the study were exposed to a magnetic field while viewing images, and their brainactivity was measured using electroencephalography (EEG). The results showed that the magnetic field altered the brain's response to the visual stimuli, suggesting that magnetic fields can modulate neural activity.It is important to note that the effects of the Earth's magnetic field on the brain are still not fully understood, and more research is needed to determine the exact mechanisms at play. Additionally, it is worth mentioning that the influence of the Earth's magnetic field on the brain is likely to be subtle and may vary from person to person.中文回答:地球磁场对大脑的影响是一个引人入胜的课题,科学家们已经研究了多年。
磁场的生物效应(biologicaleffectofmagneticfield)物理小百科
磁场的生物效应(biologicaleffectofmagneticfield)物理小
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磁场的生物效应(biologicaleffectofmagneticfield)
磁场的生物效应(biologicaleffectofmagneticfield)
研究磁场生物效应的领域也称为磁生物学。
其中包括地磁场和人工磁场对生物的作用。
地磁场强度较弱,小于80A/m(1Oe)生物定向是地磁场作用的事例之一。
澳大利亚指南白蚁会定向筑巢,鲨鱼通过自身产生的电场对地磁场定向,Blakemore(1981年)发现螺旋菌能准确地游向北磁极方向,鸟类根据磁场和重力场定向。
K.V.Frisch对蜜蜂的舞蹈语言和地磁场作用机理的精心研究,在1973年获得了诺贝尔奖。
大量研究报道表明,一定条件的强磁场会影响生物大分子的构象和功能,会使染色体变异,影响DNA复制和蛋白质表达,刺激或抑制细胞生长,旋转磁场可打碎体内结石。
磁效应对组织、器官、神经系统乃至整体都有影响。
磁场的生物效应研究对生物工程和现代医学具有重要的意义。
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电磁的生物效应 英语
电磁的生物效应英语Electromagnetic fields, or EMFs, are all around us in our modern world. They are produced by everything from Wi-Fi signals, power lines and cell phone towers, to microwaves and computer screens. While there is still much debate about the long-term health effects of exposure to EMFs, some studies suggest that they can have a range of biological effects on our bodies.Step 1: Understanding Electromagnetic FieldsBefore we can discuss the biological effects of EMFs,it's important to understand what they are. EMFs areinvisible fields of energy that are created when electrically charged particles, such as electrons, move through space. They can be created by natural sources, such as the sun and the earth's magnetic field, or by artificial sources, such as electrical appliances and electronic devices.Step 2: The Biological Effects of EMFsWhile the long-term health effects of exposure to EMFs are still not fully understood, there is evidence to suggest that they can have a range of biological effects on our bodies. Some of these effects include:- Disrupting the body's natural electromagnetic fields: Our bodies have their own natural electromagnetic field, and exposure to external EMFs can disrupt this field, potentially leading to negative health effects.- Changes in the function of cells: Studies have shown that exposure to EMFs can affect the function of cells in our bodies, including DNA damage, changes in gene expression, andaltered cell growth.- Increased risk of cancer: Some studies have suggested alink between EMF exposure and an increased risk of certain types of cancer, such as brain cancer and leukemia.Step 3: Limiting Exposure to EMFsWhile it's impossible to completely avoid exposure to EMFs in our modern world, there are steps we can take tolimit our exposure. Some strategies include:- Avoiding close proximity to sources of EMFs, such as power lines and cell phone towers.- Turning off electronic devices when they are not in use.- Using wired devices instead of wireless ones, as wireless devices produce more EMFs.- Using shielding products, such as EMF-blocking fabrics and phone cases.In conclusion, while the long-term health effects of exposure to electromagnetic fields are not yet fully understood, it's important to be aware of the potential risks and take steps to limit our exposure. By understanding what EMFs are and how they can affect our biology, we can make informed decisions about our use of electronic devices and other sources of electromagnetic radiation in our daily lives.。
碳包覆的磁性纳米材料萃取酞酸酯
第32卷㊀第12期2013年㊀㊀12月环㊀境㊀化㊀学ENVIRONMENTALCHEMISTRYVol.32,No.12December2013㊀2013年3月27日收稿.㊀∗国家自然科学基金(21207059,21171085);山东省自然科学基金(ZR2010BM027,ZR2011BQ012)资助.㊀∗∗通讯联系人,Tel:13864593698;E⁃mail:lduzsx@126.comDOI:10.7524/j.issn.0254⁃6108.2013.12.003碳包覆的磁性纳米材料萃取酞酸酯∗王颖辉1㊀腾㊀飞2㊀张媛媛3㊀张升晓3∗∗㊀刘军深3㊀吴㊀茜3(1.烟台开发区城市管理环保局,烟台,264006;㊀2.上海通用东岳汽车有限公司,烟台,264006;3.鲁东大学,烟台,264025)摘㊀要㊀利用水热反应制备碳材料包覆的Fe3O4(Fe3O4/C)纳米颗粒,并将这种材料用作固相萃取吸附剂,从环境水样中富集酞酸酯类(PAEs)污染物.由于纳米材料大的比表面积和碳材料强的吸附能力,Fe3O4/C吸附剂拥有较高的萃取效率.从500mL的环境水样中定量萃取PAEs目标物,只需50mg的吸附剂.PAEs在Fe3O4/C表面的吸附可快速达到平衡,并且用少量的乙腈就能将分析物洗脱下来.在优化的固相萃取条件下,几种PAEs的检出限在17 58ng㊃L-1之间.通过水样的加标回收率来评价该方法,其加标回收率在94.6% 106.6%之间,相对标准偏差为2% 8%.关键词㊀酞酸酯,磁性固相萃取,碳材料.酞酸酯类化合物(PAEs)作为增塑剂用于塑料制品的生产,来提高塑料强度和增大可塑性.这类物质会从塑料制品中迁移转化进入环境,从而对环境造成污染.PAEs具有三致(致突㊁致畸㊁致癌)作用,属于环境内分泌干扰物,其中有6种化合物已被美国国家环保局列为 优先监控污染物 [1].目前测定水体PAEs的前处理方法主要有液液萃取[2]㊁固相萃取[3]㊁固相微萃取[4]等方法.李玫瑰等[5]以甲苯为萃取溶剂,采用微滴液相微萃取方法快速分析水溶性食品中的PAEs.王东新[6]以中空纤维膜液相微萃取方法从天然水体中萃取了4种PAEs,并结合气相色谱进行分析.胡庆兰[7]采用自制的固相微萃取涂层,通过顶空固相微萃取与气相色谱法联用测定水中的PAES.固相萃取法以有机溶剂消耗少㊁操作简便等优点被广泛采用.王鑫等[8]采用C18小柱萃取饮用水和自来水中的4种PAEs类污染物,并用气相色谱法测定.陈永山等[9]研究了流速和除水方式等条件对C18固相萃取柱富集PAEs回收率的影响,他们还用罗里硅土净化土壤提取液,测定了土壤中的11种PAEs类污染物[10].纳米材料拥有大的比表面积和短的扩散路径,使其具有很高的萃取效率和较快的吸附速度,近年来被开发研究用作固相萃取吸附剂,从环境或生物样品中富集污染物[11⁃12].然而纳米材料填充的固相萃取小柱具有很大的反压,样品通过小柱需要消耗大量的时间.因此,磁性纳米材料用作固相萃取吸附剂的研究应运而生[13⁃15],张小乐等[16]合成了C18基团修饰的磁性介孔硅胶材料,并利用该材料建立了磁性固相萃取⁃色谱分析方法,测定了环境水样中PAEs污染物的含量.我们以前的研究[17⁃19]表明,在基于磁性纳米颗粒的固相萃取方法中,可将经过修饰的磁性纳米材料分散到样品中进行目标物吸附,达到吸附平衡后,利用磁铁快速将吸附了目标物的磁性材料分离出来,然后将目标物进行洗脱㊁测定,该快速磁分离方法避免了传统固相萃取中耗时的过柱操作,能够节省大量时间.本文制备了一种新型的磁性纳米材料(Fe3O4/C),并以该纳米材料为固相萃取吸附剂从环境水样中富集PAEs污染物.优化了吸附剂用量㊁平衡时间㊁盐度㊁pH㊁解吸附等固相萃取条件,并将这种新型的固相萃取技术与高效液相色谱(HPLC)结合,开发了一种分析环境水体中PAEs的新方法.1㊀实验部分1.1㊀化学试剂和材料㊀㊀酞酸丙酯(DPP)㊁酞酸丁酯(DBP)㊁酞酸环己酯(DCP)和酞酸辛酯(DOP)标准样品从美国Acros2244㊀环㊀㊀境㊀㊀化㊀㊀学32卷Organics公司购得.十八烷基三乙氧基硅烷购买自日本东京化学试剂公司.FeCl3㊃4H2O和FeCl2㊃6H2O从北京化学试剂公司购买.葡萄糖购买自北京红星化学公司.色谱纯的甲醇和乙腈购自美国的ThermoFisher公司.实验用的纯水来自于美国Milli⁃Q纯水系统.1.2㊀Fe3O4和Fe3O4/C纳米材料的制备和表征采用化学共沉淀的方法制备Fe3O4磁性纳米材料.首先将2.0gFeCl2㊃4H2O和5.2gFeCl3㊃6H2O溶解到25mL的预先脱氧的去离子水,再加入0.85mL浓盐酸.将以上溶液逐滴加到250mL1.5mol㊃L-1的NaOH溶液,边加边机械搅拌并通氮气保护.反应完成后,生成的黑色Fe3O4纳米颗粒用200mL去离子水洗2次,再分散到110mL的去离子水中,悬浮液中Fe3O4纳米颗粒的浓度约为20mg㊃mL-1.采用水热法在纳米Fe3O4的表面包覆一层碳材料.将0.4gFe3O4用去离子水冲洗,直至溶液为中性,然后分散到80mL0.5mol㊃L-1的葡萄糖溶液中,将此混合物超声20min后转移到聚四氟乙烯内衬的反应釜中.将反应釜在180ħ加热4h,反应完成后,用磁铁将Fe3O4/C纳米材料分离,再用去离子水和乙醇冲洗几次除去杂质.最后将反应产物分散到70mL的去离子水中得到10mg㊃mL-1的Fe3O4/C.利用透射电镜(TEM,H⁃7500,Hitachi,Japan)观察制得的吸附材料的形貌和粒径,工作电压为80kV.材料的能谱图(EDS)采用S⁃3000N能谱仪(Hitachi,Japan)测定.材料的红外谱图采用KBr压片的方式在NEXUS670傅立叶变换红外光谱仪(NicoletThermo,U.S.)采集.1.3㊀固相萃取的程序将50mg的Fe3O4/C吸附剂分散到500mL水样中,搅拌20s使吸附剂在溶液中均匀分散.将1个Nd⁃Fe⁃B强力磁铁置于容器底部进行磁分离.经过大约10min,溶液变清澈,吸附剂被完全分离到容器底部,将上清液倒掉.在吸附剂中加入2mL乙腈,超声10s后置于磁铁上分离,洗脱液转移到离心管中,取20μL进HPLC系统测定.由于塑料制品可能会释放出PAEs,因此在实验过程中使用玻璃容器.1.4㊀HPLC分析利用美国安捷伦公司的高效液相色谱系统对PAEs进行分离和分析,迪马C18色谱柱(250ˑ4.6mm,粒径5μm),采用梯度淋洗的方法分离,50%的乙腈水溶液和纯乙腈分别为流动相A和B,流速为1mL㊃min-1.梯度淋洗程序如下:前15min内B保持在40%,在10min内B由40%升至100%,保持10min,随后在3min内回到初始状态.PAEs采用紫外检测器测定,波长设在226nm.2㊀结果与讨论2.1㊀吸附剂的表征图1为Fe3O4和Fe3O4/C的透射电镜图片.Fe3O4纳米颗粒为近似球形,粒径分布比较均匀,平均直径大约为10nm.Fe3O4/C纳米颗粒呈现出明显的核壳结构,内层颜色较深的为Fe3O4核,而外层颜色相对较浅的部分是碳层.Fe3O4核使得材料具有磁性,而碳包覆层赋予材料强的吸附能力.图1㊀Fe3O4(a)和Fe3O4/C(b)纳米材料的透射电镜图(放大倍数:200000)Fig.1㊀TEMimagesofFe3O4(a),andFe3O4/C(b)nanoparticle㊀12期王颖辉等:碳包覆的磁性纳米材料萃取酞酸酯2245㊀Fe3O4和Fe3O4/C的能谱图见图2.在Fe3O4纳米颗粒的能谱图中只有一个很小的碳峰,在其表面包覆一层碳材料后,Fe3O4/C的能谱图中出现了一个较大的碳峰,其表面碳元素的摩尔百分含量达到54 4%,而铁元素的摩尔百分含量降低到13.8%,说明碳材料被成功的包覆到了Fe3O4纳米颗粒表面.图2㊀Fe3O4(a)和Fe3O4/C(b)纳米材料的能谱图Fig.2㊀EDSspectraofFe3O4(a)andFe3O4/C(b)nanoparticle利用傅立叶变换红外光谱分析Fe3O4和Fe3O4/C材料的表面基团.由图3可见,Fe3O4和Fe3O4/C的红外谱图上都有1个580cm-1的吸收峰,为Fe3O4的特征吸收峰[20].在Fe3O4/C的谱图上1700cm-1和1616cm-1的峰是C O和C C的振动吸收峰[21],这表明在水热反应的过程中,葡萄糖碳化包覆到了纳米Fe3O4的表面.1000 1300cm-1的峰是C OH的伸缩振动峰和O H弯曲振动峰[22],3100 3700cm-1之间的宽峰是O H伸缩振动峰[23].Fe3O4/C纳米材料的表面上羟基和羧基基团的存在使得该材料具有表面亲水性,能够在水溶液中分散和稳定存在,并且材料的表面亲水性降低了分析物在其表面的不可逆吸附,能够在一定程度上克服碳材料用作固相萃取洗脱困难的缺点.2.2㊀萃取条件的优化2.2.1㊀吸附剂用量的选择为了获得最优的目标物回收率,在0 100mg的范围改变Fe3O4/C吸附材料的加入量进行萃取,其结果列于图4.随Fe3O4/C吸附剂加入量的增加,PAEs的回收率也逐渐增加,当吸附剂用量为40mg时,PAEs的回收率达到最大值,吸附剂的用量继续增加,回收率基本保持平衡,不会再有明显的增加.使用没有修饰的Fe3O4作为固相萃取的吸附剂,即使其用量达到100mg,对PAEs的回收率也不会超过10%.图3㊀Fe3O4和Fe3O4/C纳米材料的红外谱图Fig.3㊀IRspectraofFe3O4andFe3O4/Cnanoparticle图4㊀吸附剂用量对PAEs回收率的影响Fig.4㊀EffectoftheamountofFe3O4/CsorbentontheextractionefficiencyofPAEs㊀㊀结果表明,能够有效吸附PAEs的是Fe3O4/C材料表面的碳层.碳纳米管和有机化合物之间的吸附主要通过疏水作用,π⁃π键㊁氢键作用和静电作用[24],Fe3O4/C纳米颗粒表面也是碳材料,因此其相互2246㊀环㊀㊀境㊀㊀化㊀㊀学32卷作用机理相同.要达到满意的回收率只需要Fe3O4/C吸附剂40mg,可能是因为Fe3O4/C材料拥有大的比表面积和碳材料的强吸附能力.为保证分析物的完全吸附,在水样中加入50mg的Fe3O4/C纳米吸附剂.2.2.2㊀乙腈用量和平衡时间的选择选用乙腈从Fe3O4/C吸附剂上解吸PAEs.为了能够将PAEs充分解吸附,将Fe3O4/C吸附剂在洗脱液中超声20s再分离.由图5(a)可以看出,只需1mL乙腈就可将80%以上的目标物解吸下来,增加乙腈的用量,PAEs的回收率略有增加,但影响不大,本实验选用2mL乙腈作为洗脱剂.传统的碳材料用作固相萃取吸附剂时,常常面临洗脱困难的问题[25].而本研究中Fe3O4/C材料较易洗脱,一方面可能是因为包覆在纳米材料上的薄层碳使得分析物的扩散路径较短,便于洗脱,另一方面可能是因为包覆上的碳材料表面是亲水性,有效避免了分析物在其上发生不可逆吸附.Fe3O4/C是超顺磁性并且拥有大的饱和磁强度,但由于其在水溶液中分散良好且表面羧基使颗粒之间存在静电斥力,因此从纯水中用磁铁分离需要较长时间.为了帮助磁分离,在水溶液中加入2mL1mol㊃L-1的NaCl溶液提供补偿离子.用一个Nd⁃Fe⁃B强力磁铁能在10min将吸附剂完全吸附到容器的底部.通常要达到完全吸附目标物和吸附剂要有充分的接触时间.改变平衡时间考察目标物回收率的变化,由图5(b)可以看出,随着平衡时间由0到120min,PAEs的回收率没有明显变化,说明分析物能在很短的时间内完全吸附到Fe3O4/C材料上.这种快的吸附速率应归功于纳米材料短的扩散路径.磁性分离和快速的吸附,使这种新型固相萃取方法能够避免耗时的过柱操作,具有可操作性和实用性.图5㊀洗脱液乙腈用量(a)和平衡时间(b)对PAEs回收率的影响Fig.5㊀Effectofacetonitrilevolume(a)andstandingtime(b)ontherecoveryofPAEs2.2.3㊀盐度和pH的选择为了考察盐度对PAHs回收率的影响,在溶液中加入NaCl调整盐度.由图6(a)可以看出,在盐度为1 500mmol㊃L-1的范围内,目标物的回收率基本不受影响,表明Fe3O4/C能从高盐度水样中萃取目标物而不受影响.吸附剂表面电荷的类型和密度通常会随溶液pH的改变而变化,因此溶液的pH可能会影响一些分析物在Fe3O4/C纳米材料上的吸附.改变溶液的pH值在3 10范围内考察其对PAHs萃取回收率的影响.由图6(b)可以看出,在设定的pH范围内PAEs的回收率没有明显变化,说明Fe3O4/C纳米材料在此pH范围内比较稳定,不会被破坏,另一方面可能是因为PAEs在设定的条件以中性分子形式存在,材料表面电荷的改变对它们的吸附没有明显的影响.基于Fe3O4/C的磁性固相萃取方法无需严格控制溶液pH,用于环境水样品的分析更加便利和稳定.2.2.4㊀水样体积选择利用Fe3O4/C作吸附剂进行固相萃取,可以将材料分散在溶液中进行吸附,达到吸附平衡后用磁铁将吸附剂分离出来进行洗脱,该方法免去了耗时的过柱操作,因此非常适用于大体积环境水样的分析.如图7所示,利用50mgFe3O4/C吸附剂,当水样的体积由200mL增加到1000mL时,PAHs的回收率没有明显下降,说明Fe3O4/C吸附材料具有大的穿透体积.通过从1000mL水样中萃取目标物并将洗脱液浓缩到2mL,PAEs的富集系数可以达到500倍.㊀㊀12期王颖辉等:碳包覆的磁性纳米材料萃取酞酸酯2247图6㊀盐度(a)和溶液pH值(b)对PAEs回收率的影响Fig.6㊀Effectofsalinity(a)andsolutionpH(b)ontheextractionefficiencyofPAEs图7㊀水样体积对PAEs回收率的影响Fig.7㊀EffectofwatersamplevolumeontherecoveyofPAEs2.3㊀分析方法相关参数固相萃取程序结合HPLC⁃UV检测建立了标准曲线,其线性范围为0.1 20ng㊃mL-1.从500mL纯水样品中萃取目标物并用2mL溶剂洗脱,PAEs的富集系数为250倍.线性范围㊁线性相关系数和检出限等参数列于表1.由表1可以看出,该方法有较高的灵敏度㊁宽的线性范围和良好的精密度,PAEs的线性相关系数R2>0.999.DPP㊁DBP㊁DCP㊁DOP的检出限(信噪比为3)分别为35㊁58㊁17㊁33ng㊃L-1.表1㊀标准曲线的方法参数Table1㊀Analyticalparametersoftheproposedmethod分析物线性范围/(ng㊃mL-1)曲线方程线性相关系数(R2)方法检出限a/(ng㊃L-1)DPP0.1 20y=0.5578x+0.05610.999835DBP0.1 20y=0.5476x+0.06340.999758DCP0.1 20y=0.9865x-0.03270.999717DOP0.1 20y=0.5948x+0.10360.999933㊀㊀a检测限根据信噪比为3确定(S/N=3),x为分析物浓度,y为紫外信号强度.2.4㊀实际水样的测定实际水样选取实验室自来水和校园人工湖的湖水,采用所建立的磁性固相萃取方法测定水样中和加标后的水样中的PAEs,3次平行测定水样和加标水样结果平均值㊁加标水样的回收率平均值及标准偏差列于表2.自来水样中DPP浓度为0.104ng㊃mL-1,其他未检出;湖水中DPP和DBP浓度分别为0 215和0.132ng㊃mL-1,其余未检出.水样中低浓度的PAEs可能来自于塑料管路或者是塑料制品的释放.加标水样中PAEs的平均回收率在94.6% 106.6%之间,相对标准偏差为2% 8%.图8为湖水样品及其加标色谱图,其峰型良好,基质相对比较干净,没有太多杂峰的干扰.2248㊀环㊀㊀境㊀㊀化㊀㊀学32卷表2㊀实际水样中PAEs的浓度及其加标回收结果Table2㊀ConcentrationsofPAEsinrealwatersamplesandrecoveriesofsamplesspikedwithanalytes水样加标/(ng㊃mL-1)测定值a/(ng㊃mL-1)DPPDBPDCPDOP回收率ʃ相对标准偏差/%bDPPDBPDCPDOP0.000.104ndcndnd自来水0.50.6120.5040.5240.533101.6ʃ3101.0ʃ2104.8ʃ6106.6ʃ855.155.104.864.79100.9ʃ2102.0ʃ497.2ʃ495.8ʃ70.000.2150.132ndnd湖水0.50.7450.6530.5230.492106.0ʃ7104.2ʃ6104.6ʃ798.4ʃ454.954.964.734.8494.7ʃ696.6ʃ594.6ʃ796.8ʃ6㊀㊀注:a3次平行测定结果.b3次测定相对标准偏差.cnd未检出.图8㊀湖水样品中PAEs的色谱图.湖水样品(a),湖水加标0.5ng㊃mL-1(b)和5ng㊃mL-1(c)Fig.8㊀HPLC⁃UVchromatogramsoflakewater(a),anditsspikedsampleswith0.5ng㊃mL-1(b)and5ng㊃mL-1(c)ofeachanalyte3㊀结论制备了超顺磁性的Fe3O4/C吸附剂,并用其从大体积环境水样中富集痕量的PAEs污染物.与传统的和文献报道的固相萃取方法比较,该方法具有如下优点:(a)超顺磁性吸附剂可以直接分散到水样中吸附目标物,达到吸附平衡后用磁铁分离洗脱,磁分离方法避免了耗时的过柱操作.(b)Fe3O4/C具有纳米材料大的比表面积和碳材料强的吸附能力,因此从大体积水样中萃取目标物只需要少量吸附剂就能获得满意的结果.(c)目标物的回收率不受溶液盐度和pH值的影响,因此在萃取时不需要对水样进行繁琐的调整.(d)Fe3O4/C吸附剂的制备方法简单,所用试剂价格低廉,无毒.在进行萃取的过程中不会在环境水样中引入有毒有害的物质,环境友好.参㊀考㊀文㊀献[1]㊀王红芬,程晗煜,洪坚平.环境中酞酸酯的污染现状及防治措施[J].环境科学与管理,2010,35(7):33⁃36[2]㊀CaiYQ,CaiYE,ShiYL,etal.Aliquid⁃liquidextractiontechniqueforphthalateesterswithwater⁃solubleorganicsolventsbyaddinginorganicsalts[J].MicrochimicaActa,2007,157:73⁃79[3]㊀王超英,李碧芳,李攻科.固相微萃取/高效液相色谱联用分析水中邻苯二甲酸酯[J].分析测试学报,2005,24(5):35⁃38[4]㊀PeñalverA,PocurllE,BorrullF,etal.Determinationofphthalateestersinwatersamplesbysolid⁃phasemicroextractionandgaschromatographywithmassspectrometricdetection[J].JChromatogrA,2000,872:191⁃201[5]㊀李玫瑰,李元星,毛丽秋.微滴液相微萃取技术用于气相色谱⁃质谱法测定食品中的酞酸酯[J].色谱,2007,25(1):35⁃38[6]㊀王东新.中空纤维液相微萃取⁃气相色谱测定不同天然水体中的酞酸酯类化合物[J].南京师范大学学报(工程技术版),2008,8(3):43⁃46[7]㊀胡庆兰.自制固相微萃取涂层同时测定水中的多环芳烃和酞酸酯[J].吉林大学学报(理学版),2013,51(2):317⁃320[8]㊀王鑫,许小苗,俞晔,等.固相萃取⁃气相色谱法同时测定水中的酞酸酯类环境激素[J].食品工业科技,2008,29(4):287⁃289[9]㊀陈永山,骆永明,章海波,等.固相萃取法处理环境水样中酞酸酯:流速与除水方式的影响[J].环境化学,2010,29(5):954⁃959[10]㊀黄玉娟,陈永山,骆永明,等.气相色谱⁃质谱联用内标法测定土壤中11种酞酸酯[J].环境化学,2013,32(4):658⁃665㊀㊀12期王颖辉等:碳包覆的磁性纳米材料萃取酞酸酯2249[11]㊀CaiYQ,JiangGB,LiuJF,etal.Multiwalledcarbonnanotubesasasolid⁃phaseextractionadsorbentforthedeterminationofbisphenolA,4⁃n⁃Nonylphenol,and4⁃tert⁃Octylphenol[J].AnalChem,2003,75:2517⁃2521[12]㊀WangHY,CampigliaAD.Determinationofpolycyclicaromatichydrocarbonsindrinkingwatersamplesbysolid⁃phasenanoextractionandhigh⁃performanceliquidchromatography[J].AnalChem,2008,80:8202⁃8209[13]㊀ZhaoXL,ShiYL,CaiYQ,etal.Cetyltrimethylammoniumbromide⁃coatedmagneticnanoparticlesforthepreconcentrationofphenoliccompoundsfromenvironmentalwatersamples[J].EnvironSciTechnol,2008,42:1201⁃1206[14]㊀ZhaoXL,ShiYL,WangT,etal.Preparationofsilica⁃magnetitenanoparticlemixedhemimicellesorbentsforextractionofseveraltypicalphenoliccompoundsfromenvironmentalwatersamples[J].JChromatogrA,2008,1188:140⁃147[15]㊀LiJD,ZhaoXL,ShiYL,etal.Mixedhemimicellessolid⁃phaseextractionbasedoncetyltrimethylammoniumbromide⁃coatednano⁃magnetsFe3O4forthedeterminationofchlorophenolsinenvironmentalwatersamplescoupledwithliquidchromatography/spectrophotometrydetection[J].JChromatogrA,2008,1180:24⁃31[16]㊀张小乐,王巍杰,张一江,等.磁性介孔硅胶萃取剂的制备及萃取性能研究[J].环境化学,2012,31(4):422⁃428[17]㊀ZhangSX,NiuHY,CaiYQ,etal.BariumalginatecagedFe3O4@C18magneticnanoparticlesforthepre⁃concentrationofpolycyclicaromatichydrocarbonsandphthalateestersfromenvironmentalwatersamples[J].AnalChimActa,2010,665:167⁃175[18]㊀ZhangSX,NiuHY,HuZJ,etal.PreparationofcarboncoatedFe3O4nanoparticlesandtheirapplicationforsolid⁃phaseextractionofpolycyclicaromatichydrocarbonsfromenvironmentalwatersamples[J].JChromatogrA,2010,1217:4757⁃4764[19]㊀ZhangSX,NiuHY,ZhangYY,etal.Biocompatiblephosphatidylcholinebilayercoatedonmagneticnanoparticlesandtheirapplicationintheextractionofseveralpolycyclicaromatichydrocarbonsfromenvironmentalwaterandmilksamples[J].JChromatogrA,2012,1238:38⁃45[20]㊀BruceIJ,SenT,Surfacemodificationofmagneticnanoparticleswithalkoxysilanesandtheirapplicationinmagneticbioseparations[J].Langmuir,2005,21:7029⁃7035[21]㊀LiY,LengTH,LinHQ,etal.PreparationofFe3O4@ZrO2core⁃shellmicrospheresasaffinityprobesforselectiveenrichmentanddirectdeterminationofphosphopeptidesusingmatrix⁃assistedlaserdesorptionionizationmassspectrometry[J].JProteomeRes,2007,6:4498⁃4510[22]㊀LiY,XuXQ,QiDW,etal.NovelFe3O4@TiO2core⁃shellmicrospheresforselectiveenrichmentofphosphopeptidesinphosphoproteomeanalysis[J].JProteomeRes,2008,7:2526⁃2538[23]㊀LimSF,ZhengYM,ZouSW,etal.CharacterizationofcopperadsorptionontoanalginateencapsulatedmagneticsorbentbyacombinedFT⁃IR,XPS,andmathematicalmodelingstudy[J].EnvironSciTechnol,2008,42:2551⁃2556[24]㊀PanB,XingBS.Adsorptionmechanismsoforganicchemicalsoncarbonnanotubes[J].EnvironSciTechnol,2008.42(24):9005⁃9013[25]㊀HennionMC.Graphitizedcarbonsforsolid⁃phaseextraction[J].JChromatogrA,2000,885:73⁃95Carboncoatedmagneticnanoparticleforsolid⁃phaseextractionofphthalateestersfromwatersamplesWANGYinghui1㊀㊀TENGFei2㊀㊀ZHANGYuanyuan3㊀㊀ZHANGShengxiao3∗㊀㊀LIUJunshen3㊀㊀WUQian3(1.CityManagementBureauofEnvironmentalProtectionofYantaiDevelopmentZone,Yantai,264006,China;2.ShanghaiGeneralMotor(Dongyue)AutoCompany,Yantai,264006,China;㊀3.LudongUniversity,Yantai,264025,China)ABSTRACTCarboncoatedFe3O4nanoparticles(Fe3O4/C)weresynthesizedbyasimplehydrothermalreactionandappliedassolid⁃phaseextraction(SPE)sorbentstoextracttracephthalateesters(PAEs)fromenvironmentalwatersamples.TheFe3O4/Csorbentspossesshighextractionefficiencyduetostrongadsorptionabilityofcarbonmaterialsandlargespecificsurfaceareaofthenanoparticles.Only50mgofsorbentswereneededtoextractPAEsfrom500mLwatersamples.Theadsorptionreachedequilibriumrapidlyandtheanalyteswereelutedwithacetonitrilereadily.SalinityandsolutionpHhadnoobviouseffectontherecoveyofPAHs,whichavoidsfussyadjustmenttowatersamplebeforeextraction.Underoptimizedconditions,thedetectionlimitofPAEswasintherangeof17 58ng㊃L-1.Theaccuracyofthemethodwasevaluatedbytherecoveriesofspikedsamples.Goodrecoveries(94.6% 106.6%)withlowrelativestandarddeviationsfrom2%to8%wereachieved.ThisnewSPEmethodprovidesseveraladvantages,suchashighextractionefficiency,highbreakthroughvolume,convenientextractionprocedure,andshortanalysistime.Keywords:PAEs,magneticsolid⁃phaseextraction,carbonmaterials.。
阳极磁增强对电解制氢速率的影响
2021年第4期工程师园地全球工业化发展,各国对能源的需求越来越大,化石燃料燃烧带来许多环境问题,开发绿色可再生新能源成为解决能源和环境问题的重要途径。
H 2是一种理想的二次能源,具有燃烧热值高,其能量密度是固体燃料的两倍多[1],来源丰富,反应产物绿色无污染等优点,被认为是未来最有潜力的能源载体和传统化石能源的最佳替代品。
H 2制备的途径有多种,传统化石燃料制氢虽然是一种工艺简单、成本低廉的制氢方法,成本可以控制在0.6~1.5元·m -3,95%以上的H 2是由煤、天然气、石油等化石燃料制取所得[2]。
但化石燃料制氢过程中不仅制得的H 2纯度低,而且会产生大量温室气体,不符合当今社会绿色工业发展的要求。
而电解水制氢法,设备简单,工艺流程相对稳定可靠,且产生的H 2纯度高,可以基本满足高纯度的H 2的需求,且不产生污染,能够循环利用,是一种相对比较理想的方法。
但缺陷是电能消耗较大,电费占整个电解水制氢费用的80%左右[3],电解水制氢的成本是目前工业化制氢领域中最高的。
在这耗能问题上,各国一直都在努力,日本开发了高温加压法,将电解水的效率提高到75%;美国建成一种SPE 工业装置,能量利用效率达90%;我国研制了双反应器制氢工艺,先进的PEM 电解工艺,使其总转换效率达95%,电解水制氢的电耗一般为4.5~5.5kWh ·m -3[4]。
通过研究者不懈的努力,电解水制氢技术不断提高,可将具有强烈波动特性的可再生能源(如水能、太阳能、风能等)转换为电能,用于电解,间接转化为氢能储存待利用,符合现代经济和环境可持续发展的要求[5]。
电解水的过程包括两个半反应,即阴极析氢反应与阳极析氧反应,二者均需要较高的过电位才能进行。
缓慢的反应动力学过程限制着整个电解水反胡兰基1,顾培发2,石华1,胡春联2,李文温2,严桂花2(1.青海省地质矿产测试应用中心,青海西宁810021;2.青海师范大学化学化工学院,青海西宁810016)摘要:本文主要在电解产氢装置上加持磁性用于探究电解产氢速率。
多极射频联合强力磁脉冲在松弛皮肤及身体塑型的非侵入性治疗
Synergistic Multi-polar Radiofrequency and Pulsed Magnetic Fields in the Non-Invasive Treatment of Skin Laxity and Body Contouring.多极射频联合强力磁脉冲在松弛皮肤及身体塑形的非侵入性治疗---R.Stephen Mulholland,MD,Plastic Surgeon,Toronto Canada 射频一直是被用在紧肤、祛皱、消脂、塑型领域最常见和最主要的非侵入性技术,并且可以达到相对显著的结果。
目前的射频技术有单级射频、双极射频、三级射频,以及最新技术多极射频。
射频的作用原理是通过高频的电流穿透真皮和皮下组织,在对表皮层没有任何伤害的情况下,高频电流会带动带电离子的碰撞,这些带电离子的碰撞将动能转化为热能。
射频的作用不会依赖于皮肤的类型及组织的选择性吸收,主要是通过热能对不同的目标组织造成不同的生物刺激作用,从而产生不同的临床效果,真皮层的主要细胞成分是纤维母细胞和由胶原蛋白、弹性蛋白和蛋白聚糖组成的细胞外基质(ECM),射频的热量会导致胶原蛋白即刻收缩和甘油三酯的分解,射频的热能能够使胶原母细胞产生炎性反应,从而造成更多的新的弹性蛋白的产生和修复,如果能采用足够的频率、足够的持续时间的射频治疗,将对皮肤产生超生理的影响,那么真皮层将随着时间的推移,产生新的蛋白质和蛋白聚糖,增强皮肤的紧实程度,从而呈现出更平滑紧致、更年轻的皮肤状态。
射频热刺激能刺激脂肪组织产生热调节,增强脂肪酶的活性,促使脂肪细胞中甘油三酯分解为游离脂肪酸和甘油。
INTRODUCTION介绍大部分的外科整形手术和美容医学工作是致力于解决患者皮肤松弛或身体轮廓的问题,无论是过去还是现在,皮肤松弛一直是采用手术拉皮的方法,不管是整容手术还是腹部去脂,乳房提升,或是手臂整形,都会通过良好的切口来切除多余的皮肤,大部分都能够使病人得到满意的结果。
Apparatus and method for decreasing bio-effects of
专利名称:Apparatus and method for decreasing bio-effects of magnetic gradient field gradients发明人:Irving N. Weinberg,Pavel Stepanov申请号:US15438269申请日:20170221公开号:US09903922B2公开日:20180227专利内容由知识产权出版社提供专利附图:摘要:A magnetic field generator includes a power source and a segmented or un-segmented coil connected to the power source to generate a time-varying magneticfield. Energy is applied to the coil so that the coil generates a time-varying magnetic fieldgradient with a magnitude of at least 1 milliTesla per meter and a rise-time of less than 1000 microseconds. The coil may be comprised of overlapping, non-overlapping or partially overlapping coil segments that may individually energized to further improve the operating characteristics of the coil to further decrease bio-effects in magnetic resonance imaging through the use of reduced pulse lengths and multi-phasic magnetic gradient pulses.申请人:Weinberg Medical Physics, Inc.地址:North Bethesda MD US国籍:US代理机构:Barnes & Thornburg LLP更多信息请下载全文后查看。
Effect of Static Magnetic Field on Extracellular P
August 2013, Vol. 7, No. 8, pp. 796-801Journal of Life Sciences, ISSN 1934-7391, USAEffect of Static Magnetic Field on Extracellular Proteins Synthesis in Escherichia coliAshti M. Amin, Fouad Houssein Kamel and Saleem S. QaderMedical Technical Institute, University of Polytechnic, Erbil 44001, IraqReceived: April 07, 2013 / Accepted: June 14, 2013 / Published: August 30, 2013.Abstract: Escherichia coli type 1 was used as a model system to determine whether static magnetic fields are a general stress factor. The bacterial broth culture were exposed to different magnetic force (400, 800, 1200 and 1600 Gauss) with incubation at 37 °C for different times (24, 48 and 72 hrs) under aerobic conditions. The response of the cells to the magnetic fields was estimated from the change in total protein synthesis by using spectrophotometer at 550 nm and by using of SDS-PAGE (Sodium dodecyl sulfate- polyacrylamide gel electrophoresis). Results concluded that was approximately no reproducible changes qualitatively in extracellular proteins were observed in the SDS-PAGE electrophoresis and did not act as a general stress factor. While, increases in the level of extra-cellular synthesis were observed using different magnetic field exposed samples when compared with the control.Key words: Magnetic field, optical density, Escherichia coli, extracellular protein, electrophoresis.1. IntroductionA magnetic field is the area of influence exerted by a magnetic force. This field is normally focused along two poles. These poles are usually designated as north and south. However these directions are not the only two that a magnetic field can have. Most magnetic objects are composed of many small fields called domains [1]. The literature on biomagnetic effects on the growth and development of various organisms has been quite extensive showing both positive and negative findings. Among the positive findings attributed to strong magnetic fields are: altered growth rate, enzyme activities, cellular metabolism, DNA synthesis and animal orientation [2].In this project, the authors tried to detect the effects of magnetic field on E. coli protein synthesis and its activity. Like other biological macromolecules such as polysaccharides and nucleic acids, proteins are essential parts of organisms and participate in virtually every process within cells. Many proteins are enzymesCorresponding author: Fouad Houssein Kamel, Ph.D., Assist. Prof., research fields: biophysics, nanotechnology. E-mail:*********************.that catalyze biochemical reactions and are vital to metabolism [3].In most bacteria, the most numerous intracellular structure is the ribosome, the site of protein synthesis in all living organisms. All prokaryotes have 70 S (where S = Svedberg units) ribosomes. The 70 S ribosome is made up of 50 S and 30 S subunits [4].Proteins are lengthy chains of amino acids which are folded back upon themselves. The nature of a protein is determined both by the amino acid chain and by the way in which the protein is folded [5].The mode of gene expression affects the location of the protein produced. The proteins may either be located in the cytoplasm of E. coli or secreted though the cell membrane [6].Genes encoded in DNA are first transcribed into pre-messenger RNA (mRNA) by proteins such as RNA polymerase. In prokaryotes like E. coli the mRNA may either be used as soon as it is produced, or be bound by a ribosome after having moved away from the nucleoid. The rate of protein synthesis is higher in prokaryotes than eukaryotes and can reach up to 20 amino acids per second[7].All Rights Reserved.Effect of Static Magnetic Field on Extracellular Proteins Synthesis in Escherichia coli797The size of a synthesized protein can be measured by the number of amino acids it contains and by its total molecular mass, which is normally reported in units of daltons (synonymous with atomic mass units), or the derivative unit kilodalton [8].To perform in vitro analysis, a protein must be purified away from other cellular components. This process usually begins with cell lysis, in which a cell’s membrane is disrupted and its internal contents released into a solution known as a crude lysate. The resulting mixture can be purified using ultracentrifugation, which fractionates the various cellular components into fractions containing soluble proteins; membrane lipids and proteins; cellular organelles and nucleic acids. Precipitation by a method known as salting out can concentrate the proteins from this lysate. Various types of chromatography are then used to isolate the protein or proteins of interest based on properties such as molecular weight, net charge and binding affinity [9].The level of purification can be monitored using various types of gel electrophoresis like SDS-PAGE if the desired protein’s molecular weight and isoelectric point are known, by spectroscopy if the protein has distinguishable spectroscopic features, or by enzyme assays if the protein has enzymatic activity. Additionally, proteins can be isolated according their charge using electro focusing [8].2. Materials and MethodsBacterial suspension of Escherichia coli which was isolated from urine sample and cultured on MacConkey agar will be inoculated in to five groups of tube containing nutrient broth media and exposed each one of these four tubes in one of magnetic field which were prepared with different forces including 400, 800, 1200, 1600 G and measured by Teslometer in Physical Department of College of Science. The tube number five as a control without magnetic power, all of these tubes incubated separately for 24, 48 and 72 hrs at 37 ºC. The inoculation of API kit (BioMerieux Company) with bacteria from each groups were performed separately to identify the enteric bacteria type [8]. A plastic strip holding twenty mini-test tubes is inoculated with a saline suspension of a pure culture. This process also rehydrates the desiccated medium in each tube. A few tubes are completely filled [7], and some tubes are overlaid with mineral oil such that anaerobic reactions can be carried out (ADH, LDC, ODC, H2S, URE) [10].After incubation in a humidity chamber for 18-24 hrs at 37 °C, the color reactions are read. Note especially the color reactions for amino acid decarboxylations (ADH through ODC) and carbohydrate fermentations (GLU through ARA). The amino acids tested are (in order) arginine, lysine and ornithine. Decarboxylation is shown by an alkaline reaction (red color of the particular pH indicator used). The carbohydrates tested are glucose, mannitol, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin and arabinose. Fermentation is shown by an acid reaction (yellow color of indicator). Hydrogen sulfide production (H2S) and gelatin hydrolysis (GEL) result in a black color throughout the tube. A positive reaction for tryptophan deaminase (TDA) gives a deep brown color with the addition of ferric chloride [10].The identification and separation of proteins were measured by SDS-PAGE (sodium dodecyl sulfate- polyacrylamide gel electrophoresis). According to API test, it can be known which types of proteins in the experiment have effected by magnetic field, so these proteins should be separated by SDS-PAGE method. Proteins separate by charge when exposed to an electric field. In order to separate proteins electrophoretically by size, they are first mixed with SDS, a negatively charged detergent. SDS binds to all proteins in the mixture and denatures them so that each molecule assumes a random coil configuration and becomes negatively charged. Thus, each protein will migrate toward the anode during electrophoresis, and its rate of migration will depend on its size, larger protein take longer to slither through the gel matrix, while smallerAll Rights Reserved.Effect of Static Magnetic Field on Extracellular Proteins Synthesis in Escherichia coli 798one migrate more rapidly through the gel matrix. At the end, the proteins in the gel are visualized by Coomassie brilliant blue (250 R), and the particular banding pattern, or fingerprint, of each bacterial samples can be discerned by comparing with protein marker [9].The concentration and activity of the extracellular enzymes (proteins) are measured by Total Protein kit (Biuret Method Ready for use). Total proteins were measured for both treated and non treated groups by spectrophotometer and by using Biolabo reagents so high rate of proteins may be caused by an increased in the concentration of specific proteins [11]. 1 mL of total protein reagent which contain (sodium hydroxide, Na-K tartrate, potassium iodide and copper 11 sulfate) mix with 20 µL bacterial protein for each group separately, 1 mL of reagent mix with 20 µL standard (which contain Bovine Albumin 6 g/dL) and 1 mL of reagent mix with 20 µL ddH2O as reagent blank. Mix well, let stand for 10 minutes at room temperature, record absorbance at 550 nm against reagent blank [11].3. ResultsIn this project, the E. coli was used as a model system to determine the magnetic fields (MFs) effects. Table 1 and Fig. 1 show the change in the E. coli type 1 enzymes such as ADH, CIT and GEL. It is clear from Table 1 and Fig. 1 that the bacterial exposure period 24 hrs to different forces of SMF (400, 800, 1200 and 1600 G), appears that treating bacterial cells can inhibit or promote enzyme activity according to API test, these results are in a good agreement with Gremion et al. [12]. The literature on biomagnetic effects on the growth and development of various organisms has been quite extensive showing both positive and negative findings. Among the positive findings attributed to strong magnetic fields are: altered growth rate, enzyme activities, cellular metabolism, DNA synthesis and animal orientation.Resulted in the inhibition of ADH, CIT and GEL enzymes at 24 hours incubation time (Table 1 and Fig.1) but 48 hrs and 72 hrs incubation times shows that only ADH and CIT are effected to SMF, as shown in Table 2 and Fig. 2. By this test the E. coli which were type 1 could be identified.SDS-Gel for E. coli to identify bands that affected by different forces of magnetic fields, with this experiment the authors wanted to isolate the proteins that are affected by magnetic forces. 10% SDS-PAGE stained with Coomassie for five different samples of the E. coli, as shown in Fig. 3. Indeed, normal bands of approximately 86, 78, 60, 58, 56, 43, 48, 34, 27 and 20 kDa were observed in the presence of E. coli suspension, lysozyme and magnetic fields were used in this experiment.Total proteins were measured for both treated and non treated groups by spectrophotometer at 550 nm and by using Biolabo reagents so high rate of proteins may be caused by an increased in the concentration of specific proteins, as seen in Table 3.4. DiscussionExposing of bacteria to different forces of magnetic fields leads to change the bacteria enzymes according to API test these results are in a good agreement with Gremion et al. [13]. The literature on biomagnetic effects on the growth and development of various organisms has been quite extensive showing both positive and negative findings. Among the positive findings attributed to strong magnetic fields are:Table 1 The API test for E. coli samples with magnetic forces and without at 24 hrs.24 hrsARAAMYMELSACRHASORINOManGLUGELVPINDTDAUREH2SCITODCLDCADHONDGControl+-++++-++--++---++++400+-++++-++--++--+++-+800+-++++-+++-++--+++-+1200+-++++-++--++--+++-+1600+-++++-++--++--+++-+All Rights Reserved.Effect of Static Magnetic Field on Extracellular Proteins Synthesis in Escherichia coli 799Fig. 1 The API test for E. coli samples with magnetic forces at 24 hrs.Table 2 The API test for E. coli at 48 hrs and 72 hrs.48 & 72hrs ARAAMY MEL SAC RHA SOR INO Man GLU GEL VP IND TDA URE H 2S Cit ODC LDC ADH ONDG Control + - + + + + - + + - - + + - - - + + + + 400 + - + + + + - + + - - + + - - + + + - + 800 + - + + + + - + + - - + + - - + + + -+ 1200 + - + + + + - + + - - + + - - + + + - + 1600+-++++-++--++--+++-+Fig. 2 The API test for E. coli at 48 hrs and 72 hrs.altered growth rate, enzyme activities, cellular metabolism, DNA synthesis and animal orientation. According of the SDS-PAGE, the bacterial cells were exposed to different forces of magnetic fieldunder aerobic conditions (24 hrs), no reproduciblechanges were observed in the SDS-gel when compared with the control it means that no effect ofthe different forces of magnetic fields were detectedAll Rights Reserved.800Fig. 3 SDS-g G; 4: 800 G; 5Table 3 Th measured by Samples in different MF Control 400 G 800 G 1200 G 1600 Gwhen compa 3, it can be field causes samples whe 5. Conclus The bacte are effected According t forces of ma with the c activity are total protein Effect of St gel for E. coli t 5: 1200 G; 6: 1he total protei spectrophotom ncubation in forces ared with the seen that the the increase en compared sionserial enzymes to magnetic the SDS-PAG agnetic fields ontrol. The effected by n test.tatic Magneti to identify ban 1600 G.in of E. coli meter. nTotal protein 348.5 448.4 401.2 398.3 351.01control. Acc e different fo of total prote with the cont s, such as AD field accord GE, no effect was detected concentratio magnetic fie ic Field on Ex 6nds that affecte for each grou at 550 nmcording the T orces of magn ein in all expo trol.DH, CIT and G ding to API t t of the diffe d when comp on and prot elds accordin xtracellular P5 4 ed by different up isTablenetic osed GEL ests.erent ared teins ng to Ac T the coll Cen stud Re [1][2][3][4][5]roteins Synth 3 2 1t forces of mag knowledgm The authors g Rizgari Teac lection. Grate nter staff grou dent of Scienc ferencesD. Todorovi Rauš, L. Nik field (50 mT Tenebrio (Ins (2013) 44-50E. Aarholt, low-frequenc Phys Med Bi A.R. Davis, W the Living Sy K. Mitra, C. S protein-condu Nature 438 (2C.M. Dobson folding, in:hesis in Esch 1gnetic fields. 1:mentsgratefully ack ching Hospita eful thanks f up, and also ce College fo ć, T. Markovi ćkoli ć, et al., The T) on developm secta, Coleopte .E.A. Flinn, cy magnetic fie ol 26 (4) (1981W.C.Jr. Rawls, ystem, Acres, U Schaffitzel, T. S ucting channel b 2005) 318-324.n, The nature R.H. Pain (E herichia coli: Marker; 2: C knowledge th al laboratorie for the Medi to Sazan Qad or her help in , Z. Proli ć, S. e influence of ment and moto era), Int J Radi C.W. Smith elds on bacteria ) 613-621. Magnetism and USA, Kansas Ci Shaikh, Structur bound to a trans and significan Ed.), Mechanism 150 10080 60 50 40 30 25Control; 3: 400he support of es for sample cal Research dir the Ph.D.the analysis.Mihajlovi ć, S.static magnetic or behaviour of iat Biol. 89 (1)h, Effects of al growth rate,d Its Effects on ity, 1974. re of the E. coli slating ribosom nce of protein ms of Protein 0 fe h . .c f ) f , n i m, n nAll Rights Reserved.Effect of Static Magnetic Field on Extracellular Proteins Synthesis in Escherichia coli801Folding, Oxford University Press, Oxford shire, 2000, pp.1-28.[6] F.A. Marston, The purification of eukaryotic polypeptidessynthesis in E. coli,Biochem J. 240 (1) (1986 November15) 1-12.[7]L. Potenza, L. Ubaldi, R. De Sanctis, R. De Bellis, L.Cucchiarini, M. Dachà, Effects of a static magnetic fieldon cell growth and gene expression in Escherichia coli,Mutat Res. 561 (1-2) (2004 Jul 11) 53-62.[8] A. Fulton, W. Isaacs, Titin, a huge, elastic sarcomericprotein with a probable role in morphogenesis, BioEssays13 (4) (1991) 157-161.[9]J. Wiltfang, N. Arold, V. Neuhoff, A new multiphasicbuffer system for sodium dodecyl sulfate-polyacrylamidegel electrophoresis of proteins and peptides with molecular masses 100,000-1,000, and their detection withpicomolar sensitivity, Electrophoresis 12 (5) (1991)352-366.[10]J. Hey, A. Posch, A. Cohen, Fractionation of complexprotein mixtures by liquid-phase isoelectric focusing,Methods in Molecular Biology 424 (2008) 225-239.[11]P.C. Appelbaum, J. Stavitz, M.S. Bentz, Four methodsfor identification of gram-negative no fermenting rods:Organisms more commonly encountered in clinicalSpecimens, J. Clin. Microbiol. 12 (1980) 271-278.[12] C.A. Burtis, E.R. Ashwoo, Text Book of ClinicalChemistry, 3rd ed., W.B. Saunders, 1999, pp. 477-530. [13]G. Gremion, D. Gaillard, P.F. Leyvraz, B.M. Jolles,Effect of biomagnetic therapy versus physiotherapy fortreatment of knee osteoarthritis: A randomized controlledtrial, J Rehabil Med. 41 (13) (2009 Nov) 1090-1095.All Rights Reserved.。
Effects of magnetic fields on biological systems
Effects of magnetic fields onbiological systems磁场对生物系统的影响磁场是我们周围的一个普遍存在的自然现象,它是指物体围绕着自己的轴旋转以创建一个绕轴旋转的电场。
磁场可以直接或间接地影响与之相互作用的物质,其中包括生物系统。
在现代科学中,人们已经开始意识到磁场对生物系统的影响,研究称为磁生物学。
磁场的来源可以是自然的,例如地球磁场,也可以是人造的,例如电磁设备和磁共振成像仪。
现代人类在各个方面离不开电磁设备,如手机、电视、电脑等,而磁共振成像仪已经成为诊断医学中不可或缺的工具。
然而,这些设备产生的磁场是否对生物系统产生负面影响是一个值得关注的问题。
生物系统受磁场影响的机制还不完全清楚,但已经发现存在一些可能的影响机制,例如:1. 对于含有大量铁分子的细胞,磁场可以改变其代谢。
铁是许多生物分子的组成部分,包括血红蛋白和储存铁的蛋白。
一些研究表明,强磁场可能会改变铁的代谢,导致其离子状态改变、释放或在组织中聚集。
2. 磁场可以改变细胞膜的状态。
细胞膜起着保护和选择性渗透的作用。
一些研究表明,磁场可能会改变细胞膜的物理状态,从而影响细胞与环境之间的交互。
3. 磁场可能会影响生物分子的活性。
生物分子的活性受其周围环境的影响,而磁场可能会改变这一环境,从而影响分子的构象、反应速率和产物选择性。
具体而言,磁场对人类和其他生物的影响方式和级别尚未完全确定。
一些研究表明,磁场可能会对人类和其他动物的生理和心理机能产生不利影响,例如:1. 磁场可能会干扰人类和动物的睡眠。
一些研究表明,磁场可能会干扰人类和动物的大脑活动,从而影响睡眠质量。
2. 磁场可能会导致头痛和其他健康问题。
一些研究表明,长时间暴露在较强的磁场中可能会导致头痛、恶心、眩晕等健康问题。
3. 磁场可能会影响人类和动物的行为。
一些研究表明,磁场可能会影响动物的迁徙和导航能力,也可能会影响人类的认知和情绪。
介绍地球磁场的英语作文
介绍地球磁场的英语作文Earth's magnetic field is like a giant invisible shield wrapped around our planet. It's like our own cosmic bodyguard, deflecting harmful solar winds and cosmic rays away from us. Without it, we'd be in serious trouble, getting bombarded by all sorts of dangerous radiation from space.Think of it as Earth's own magnetic superhero cape, always ready to swoop in and save the day. But unlike a regular superhero, this cape isn't made of fabric or fancy materials. It's actually created by the swirling molteniron deep inside the Earth's core. That's some serious superhero material right there!But just like any superhero, Earth's magnetic field has its weaknesses too. Sometimes it gets a little wonky and starts flipping its poles. Yup, you heard that right –it's like the magnetic North Pole decides to take a vacation down to the South Pole for a while. Scientistsaren't exactly sure why it does this, but they think it has something to do with the chaotic dance of the molten iron inside the Earth's core.And hey, did you know that animals can actually sense Earth's magnetic field? It's true! Birds, turtles, and even some bacteria use it like a built-in GPS to navigate their way around the world. Talk about having a natural sense of direction!So next time you look up at the sky and marvel at the stars, take a moment to appreciate Earth's magnetic field quietly working its magic to keep us safe. It might not wear a flashy costume or have a catchy theme song, but it's definitely one of the coolest superheroes out there.。
有机金属卤化物钙钛矿发光的磁场效应
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文档下载后可定制随意修改,请根据实际需要进行相应的调整和使用,谢谢!并且,本店铺为大家提供各种各样类型的实用资料,如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等,如想了解不同资料格式和写法,敬请关注!Download tips: This document is carefully compiled by the editor. I hope that after you download them, they can help you solve practical problems. The document can be customized and modified after downloading, please adjust and use it according to actual needs, thank you!In addition, our shop provides you with various types of practical materials, such as educational essays, diary appreciation, sentence excerpts, ancient poems, classic articles, topic composition, work summary, word parsing, copy excerpts, other materials and so on, want to know different data formats and writing methods, please pay attention!有机金属卤化物钙钛矿是一类备受研究关注的新型光电材料,其优异的光电性能使其在光电领域有着广泛的应用前景。
介绍地球磁场的作文英文
介绍地球磁场的作文英文The Earth's magnetic field is a powerful force that surrounds our planet, protecting it from the harmfuleffects of solar radiation.It is generated by the movement of molten iron in the Earth's outer core, creating a complex and ever-changing magnetic field that extends into space.This magnetic field is essential for life on Earth, as it helps to protect the atmosphere from being stripped away by solar winds and cosmic rays.Without the Earth's magnetic field, life as we know it would not be possible, as the harsh conditions of space would make our planet uninhabitable.The magnetic field also plays a crucial role in navigation, as it allows animals such as birds and sea turtles to navigate across long distances.In addition, the Earth's magnetic field has been used by humans for centuries for navigation and orientation, and it continues to be an important tool for modern technology, such as compasses and GPS systems.Overall, the Earth's magnetic field is a fascinating and essential part of our planet, providing protection, navigation, and a glimpse into the inner workings of the Earth.。
1.仿生脉冲电磁场对去卵巢大鼠骨质疏松治疗作用及机理的初步探讨
・论 著・仿生脉冲电磁场对去卵巢大鼠骨质疏松治疗作用及机理的初步探讨谢 肇1,李起鸿1,许建中1,孟 萍2,谭祖键1(第三军医大学西南医院:1.骨科,全军矫形外科中心;2.老年科,重庆400038) 摘 要:目的 观察仿生电磁场对去卵巢大鼠骨质疏松的治疗作用,探讨其作用机理。
方法 6月龄雌性未孕Wistar大鼠40只,按体质量随机分为模型组(OVX)、假手术组(Sham)、仿生电磁场治疗组(EM)、雌激素治疗组(E)。
OVX、EM、E组行双侧卵巢切除术,Sham组行假手术。
术后8周,E组苯甲酸雌二醇肌肉注射,0.5mg/kg,1次/2周。
EM组大鼠暴露于仿生电磁场治疗,1h・1次-1・d-1,OVX、Sham组不予以任何处理,作为对照组。
治疗10周后测量腰椎骨密度、椎体的最大载荷、右侧胫骨骨结构以及血尿生化。
结果 仿生电磁场显著改善了大鼠腰椎骨密度(P<0.01)、最大载荷(P<0.01),骨结构也明显改善。
血尿生化显示骨形成大于骨吸收。
结论 仿生电磁场对去卵巢大鼠骨质疏松具有明显的治疗作用,增强成骨细胞功能,抑制破骨细胞功能是其治疗作用的可能机理之一。
关键词:仿生电磁场;绝经后骨质疏松症;治疗作用;机理中图分类号:R365.68文献标识码:A文章编号:167128348(2005)0720968203The therapeuetic effect of bionics electromagnetic f ields in OVX2induced osteoporosis rats and its mechanismX I E Zhao,L I Qi2hong,X U J ian2z hong,et al.(Department of Orthopedics,Orthopedic Center of PL A,S outhwest Hos pital,the T hi rd M ilitary Medical Universit y,Chongqing400038,China)Abstract:Objective To investigate the therapeuetic effect of bionics electromagnetic fields and to explore the mechanism of that in postmenopausal osteoporosis.Methods The fourty62month old female Wistar rats were randomly divided into four different groups:ovariectomy group(OVX),sham operation group(Sham),E group(Estrogen+OVX)and EM group(B EMF+OVX). All rats were subjected to bilateral ovariectomy except sham operation group.After8weeks operation,the E group rats were given estrogen0.5mg/kg,1/2W.EM group rats were exposed to bionics electromagnetic fields,1h/d.OVX and Sham group rats were given nothing.After the treatments finished,the specimens of left tibia.R esults After the treatment with B EMF,BMD at the lumbar spine significantly increased by24.3%(vs.OVX),the maximum load of EM group markedly significantly increased by 22%(vs.OVX)(P<0.01).The trabecular volume and trabecular connections significantly increased(vs.OVX).The TRA P concentrations in EM group decreased(vs.OVX)(P<0.05),The B GP concentrations,the AL P concentrations increased(vs. OVX)(P<0.05).Conclusion The B EMF are useful in the treatment of postmenopausal osteoporosis resulting f rom ovariectomy. Building up the osteoblasts and controlling the osteoclasts may be one of mechanisms of therapeutic effect of B EMF on postmenopa2 usal osteoporosis.K ey w ords:bionics electromagnetic fields;postmenopausal osteoporosis;therapeutic effect;mechanism 绝经后骨质疏松症是危害中、老年女性健康的常见疾病,从根本上彻底治愈目前尚无可能。