On Intrinsic Magnetic Moments In Black Hole Candidates

关于磁化方法的物理题英文回答：Magnetic Materials and Magnetization Methods.Magnetic materials are substances that can be magnetized when exposed to a magnetic field. Magnetization is the process of aligning the magnetic moments of the atoms or molecules in a material in a certain direction. There are different methods for magnetizing materials, each with its own advantages and disadvantages.Types of Magnetization Methods:Saturation Magnetization: This method involves exposing a material to the maximum possible magnetic field strength to align all of its magnetic moments.Remanent Magnetization: After a material has been saturated, it will retain some of its magnetization evenwhen the magnetic field is removed. This residual magnetization is called remanence.Hysteresis: The relationship between the applied magnetic field strength and the magnetization of a material is often not linear. This nonlinearity is called hysteresis, and it can affect the magnetic properties of the material.Demagnetization: This process involves reducing the magnetization of a material by exposing it to a magnetic field in the opposite direction of its original magnetization.Factors Affecting Magnetization:The magnetization of a material depends on several factors, including:Material Properties: The composition, microstructure, and magnetic susceptibility of the material influence its ability to be magnetized.Magnetic Field Strength: The strength of the applied magnetic field determines the degree of magnetization.Temperature: High temperatures can reduce the magnetization of a material.Mechanical Stress: Applying mechanical stress to a material can affect its magnetic properties.Applications of Magnetization:Magnetization has various applications in different fields, such as:Data Storage: Magnetic recording is used in hard disk drives and magnetic tapes to store data.Magnetic Resonance Imaging (MRI): MRI scanners use powerful magnets to create images of the inside of the human body.Electric Motors and Generators: Magnets are used inelectric motors to convert electrical energy into mechanical energy and in generators to convert mechanical energy into electrical energy.Magnetic Separation: Magnets can be used to separate magnetic materials from non-magnetic materials.中文回答：磁性材料和磁化方法。

永磁体磁矩剩磁体积之间的关系The relationship between the magnetic moment and the remanent magnetization in permanent magnets is a complex and interesting topic. Permanent magnets, also known as ferromagnetic materials, have the ability to retain their magnetization once they have been magnetized. This property is crucial for their widespread applications in various technologies and industries.永磁体的磁矩是指一个永磁体单位磁极矩大小的一个向量，它受永磁体内部微观磁矩的影响。

而剩磁则是永磁体去除外磁场后仍然具有残余磁场的能力。

磁矩和剩磁之间的关系可以通过永磁体的磁化曲线来描述。

永磁体磁矩与剩磁体积之间的关系是复杂的，需要综合考虑永磁体的材料、形状、制备工艺等因素。

The relationship between the magnetic moment and the remanent magnetization can be understood through the hysteresis curve of a permanent magnet. When a permanent magnet is subjected to an external magnetic field, it becomes magnetized and the magnetic moments align in a particular direction. When the external magnetic field is removed, some of the magnetic moments in the material mayremain aligned, leading to remanent magnetization. The magnitudeof the remanent magnetization is directly related to the magnetic moment of the material.磁矩和剩磁之间的关系也受到永磁体的晶粒大小、磁畴结构以及化学成分等因素的影响。

Chapter 6 Magnetism of MatterThe history of magnetism dates back to earlier than 600 B.C., but it is only in the twentieth century that scientists have begun to understand it, and develop technologies based on this understanding. Magnetism was most probably first observed in a form of the mineral magnetite called lodestone, which consists of iron oxide-a chemical compound of iron and oxygen. The ancient Greeks were the first known to have used this mineral, which they called a magnet because of its ability to attract other pieces of the same material and iron.The Englishman William Gilbert(1540-1603) was the first to investigate the phenomenon of magnetism systematically using scientific methods. He also discovered that Earth is itself a weak magnet. Early theoretical investigations into the nature of Earth's magnetism were carried out by the German Carl Friedrich Gauss(1777-1855). Quantitative studies of magnetic phenomena initiated in the eighteenth century by Frenchman Charles Coulomb(1736-1806), who established the inverse square law of force, which states that the attractive force between two magnetized objects is directly proportional to the product of their individual fields and inversely proportional to the square of the distance between them.Danish physicist Hans Christian Oersted(1777-1851) first suggested a link between electricity and magnetism. Experiments involving the effects of magnetic and electric fields on one another were then conducted by Frenchman Andre Marie Ampere(1775-1836) and Englishman Michael Faraday(1791-1869), but it was the Scotsman, James Clerk Maxwell(1831-1879), who provided the theoretical foundation to the physics of electromagnetism in the nineteenth century by showing that electricity and magnetism represent different aspects of the same fundamental force field. Then, in the late 1960s American Steven Weinberg(1933-) and Pakistani Abdus Salam(1926-96), performed yet another act of theoretical synthesis of the fundamental forces by showing that electromagnetism is one part of the electroweak force. The modern understanding of magnetic phenomena in condensed matter originates from the work of two Frenchmen: Pierre Curie(1859-1906), the husband and scientific collaborator of Madame Marie Curie(1867-1934), and Pierre Weiss(1865-1940). Curie examined the effect of temperature on magnetic materials and observed that magnetism disappeared suddenly above a certain critical temperature in materials like iron. Weiss proposed a theory of magnetism based on an internal molecular field proportional to the average magnetization that spontaneously align the electronic micromagnets in magnetic matter. The present day understanding of magnetism based on the theory of the motion and interactions of electrons in atoms (called quantum electrodynamics) stems from the work and theoretical models of two Germans, Ernest Ising and Werner Heisenberg (1901-1976). Werner Heisenberg was also one of the founding fathers of modern quantum mechanics.Magnetic CompassThe magnetic compass is an old Chinese invention, probably first made in China during the Qin dynasty (221-206 B.C.). Chinese fortune tellers used lodestonesto construct their fortune telling boards.Magnetized NeedlesMagnetized needles used as direction pointers instead of the spoon-shaped lodestones appeared in the 8th century AD, again in China, and between 850 and 1050 they seemto have become common as navigational devices on ships. Compass as a Navigational AidThe first person recorded to have used the compass as a navigational aid was Zheng He (1371-1435), from the Yunnan province in China, who made seven ocean voyages between 1405 and 1433.有关固体磁性的基本概念和规律在上个世纪电磁学的发展史中就开始建立了。

2011年技术物理学院08级（激光方向）专业英语翻译重点！！！作者：邵晨宇Electromagnetic电磁的principle原则principal主要的macroscopic宏观的microscopic微观的differential微分vector矢量scalar标量permittivity介电常数photons光子oscillation振动density of states态密度dimensionality维数transverse wave横波dipole moment偶极矩diode 二极管mono-chromatic单色temporal时间的spatial空间的velocity速度wave packet波包be perpendicular to线垂直be nomal to线面垂直isotropic各向同性的anistropic各向异性的vacuum真空assumption假设semiconductor半导体nonmagnetic非磁性的considerable大量的ultraviolet紫外的diamagnetic抗磁的paramagnetic顺磁的antiparamagnetic反铁磁的ferro-magnetic铁磁的negligible可忽略的conductivity电导率intrinsic本征的inequality不等式infrared红外的weakly doped弱掺杂heavily doped重掺杂a second derivative in time对时间二阶导数vanish消失tensor张量refractive index折射率crucial主要的quantum mechanics 量子力学transition probability跃迁几率delve研究infinite无限的relevant相关的thermodynamic equilibrium热力学平衡（动态热平衡）fermions费米子bosons波色子potential barrier势垒standing wave驻波travelling wave行波degeneracy简并converge收敛diverge发散phonons声子singularity奇点（奇异值）vector potential向量式partical-wave dualism波粒二象性homogeneous均匀的elliptic椭圆的reasonable公平的合理的reflector反射器characteristic特性prerequisite必要条件quadratic二次的predominantly最重要的gaussian beams高斯光束azimuth方位角evolve推到spot size光斑尺寸radius of curvature曲率半径convention管理hyperbole双曲线hyperboloid双曲面radii半径asymptote渐近线apex顶点rigorous精确地manifestation体现表明wave diffraction波衍射aperture孔径complex beam radius复光束半径lenslike medium类透镜介质be adjacent to与之相邻confocal beam共焦光束a unity determinant单位行列式waveguide波导illustration说明induction归纳symmetric 对称的steady-state稳态be consistent with与之一致solid curves实线dashed curves虚线be identical to相同eigenvalue本征值noteworthy关注的counteract抵消reinforce加强the modal dispersion模式色散the group velocity dispersion群速度色散channel波段repetition rate重复率overlap重叠intuition直觉material dispersion材料色散information capacity信息量feed into 注入derive from由之产生semi-intuitive半直觉intermode mixing模式混合pulse duration脉宽mechanism原理dissipate损耗designate by命名为to a large extent在很大程度上etalon 标准具archetype圆形interferometer干涉计be attributed to归因于roundtrip一个往返infinite geometric progression无穷几何级数conservation of energy能量守恒free spectral range自由光谱区reflection coefficient（fraction of the intensity reflected）反射系数transmission coefficient（fraction of the intensity transmitted）透射系数optical resonator光学谐振腔unity 归一optical spectrum analyzer光谱分析grequency separations频率间隔scanning interferometer扫描干涉仪sweep移动replica复制品ambiguity不确定simultaneous同步的longitudinal laser mode纵模denominator分母finesse精细度the limiting resolution极限分辨率the width of a transmission bandpass透射带宽collimated beam线性光束noncollimated beam非线性光束transient condition瞬态情况spherical mirror 球面镜locus（loci）轨迹exponential factor指数因子radian弧度configuration不举intercept截断back and forth反复spatical mode空间模式algebra代数in practice在实际中symmetrical对称的a symmetrical conforal resonator对称共焦谐振腔criteria准则concentric同心的biperiodic lens sequence双周期透镜组序列stable solution稳态解equivalent lens等效透镜verge 边缘self-consistent自洽reference plane参考平面off-axis离轴shaded area阴影区clear area空白区perturbation扰动evolution渐变decay减弱unimodual matrix单位矩阵discrepancy相位差longitudinal mode index纵模指数resonance共振quantum electronics量子电子学phenomenon现象exploit利用spontaneous emission自发辐射initial初始的thermodynamic热力学inphase同相位的population inversion粒子数反转transparent透明的threshold阈值predominate over占主导地位的monochromaticity单色性spatical and temporal coherence时空相干性by virtue of利用directionality方向性superposition叠加pump rate泵浦速率shunt分流corona breakdown电晕击穿audacity畅通无阻versatile用途广泛的photoelectric effect光电效应quantum detector 量子探测器quantum efficiency量子效率vacuum photodiode真空光电二极管photoelectric work function光电功函数cathode阴极anode阳极formidable苛刻的恶光的irrespective无关的impinge撞击in turn依次capacitance电容photomultiplier光电信增管photoconductor光敏电阻junction photodiode结型光电二极管avalanche photodiode雪崩二极管shot noise 散粒噪声thermal noise热噪声1.In this chapter we consider Maxwell’s equations and what they reveal about the propagation of light in vacuum and in matter. We introduce the concept of photons and present their density of states.Since the density of states is a rather important property，not only for photons，we approach this quantity in a rather general way. We will use the density of states later also for other(quasi-) particles including systems of reduced dimensionality.In addition,we introduce the occupation probability of these states for various groups of particles.在本章中，我们讨论麦克斯韦方程和他们显示的有关光在真空中传播的问题。

核磁共振英语词汇英文回答：Nuclear magnetic resonance (NMR) is a powerfulanalytical tool that utilizes magnetic fields and radio waves to investigate the properties of atoms and molecules. It offers a non-destructive and versatile technique for characterizing materials at the atomic and molecular level. NMR has various applications across multiple scientific disciplines, including chemistry, physics, biology, and medicine.The basic principle of NMR involves the interaction between atomic nuclei with a magnetic field. Certain nuclei, such as 1H (proton), 13C, 15N, and 31P, possess anintrinsic magnetic moment due to their nuclear spin. When placed in a magnetic field, these nuclei align with or against the field, resulting in two distinct energy states. By applying radio waves to the sample at specific frequencies, it is possible to induce transitions betweenthese energy states.The absorption of radio waves by the nuclei leads to the resonance phenomenon, which forms the basis of NMR. The resonant frequency for a particular nucleus depends on its chemical environment, including the electron density and surrounding atoms. By analyzing the resonance frequencies and patterns, NMR provides detailed information about the structure, dynamics, and interactions of molecules.NMR spectroscopy is a widely used technique for identifying and quantifying different atoms and functional groups within molecules. It plays a crucial role in determining the molecular structure of organic and inorganic compounds, as well as studying chemical reactions and reaction mechanisms. NMR also finds applications in drug discovery and development, protein structure determination, and metabolomics.In medical imaging, NMR is employed as a non-invasive tool for obtaining detailed anatomical and functional information about the human body. Magnetic resonanceimaging (MRI) utilizes NMR techniques to create high-resolution images of organs, tissues, and blood vessels. MRI is particularly valuable for diagnosing and monitoring a wide range of medical conditions, including brain disorders, cardiovascular diseases, and musculoskeletal injuries.NMR also has applications in other fields, such as materials science, polymer characterization, and geological studies. It is a versatile technique that provides valuable insights into the structure, dynamics, and properties of various materials and systems.In summary, nuclear magnetic resonance (NMR) is a powerful analytical tool that offers a non-destructive and versatile approach for investigating the properties of atoms and molecules. Its applications span multiple scientific disciplines, including chemistry, physics, biology, and medicine, providing insights into molecular structure, dynamics, and interactions.中文回答：核磁共振（NMR）是一种强大的分析工具，利用磁场和射频波来研究原子和分子的性质。

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The document can be customized andmodifiedafter downloading,please adjust and use it according toactual needs, thank you!In addition, our shop provides you with various types ofpractical materials,such as educational essays, diaryappreciation,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 andwriting methods,please pay attention!示例作文篇一：Title: Pursuit of Passion or Practicality: A Student's DilemmaIn the vast landscape of academic opportunities, studentsoften find themselves at a crossroads, contemplating the choice between selecting a major based on personal interest or one that promises better job prospects. This decision, fraught with anticipation and uncertainty, is not an easy one to make. It is a question that echoes within the minds of countless young scholars, each weighing the delicate balance between heart and head.On one hand, the allure of a passion-based major lies in its capacity to ignite a lifelong love for learning. It is a journey that begins with the thrill of discovery, where one delves into subjects that spark curiosity and ignite the imagination. These majors, such as art, music, or literature, offer a sense of fulfillment beyond mere employment. They foster creativity,critical thinking, and a deep understanding of the human experience. Pursuing one's passion, it is argued, leads to a more satisfying life, even if the financial rewards may not be immediate or substantial.However, the practical side cannot be ignored. The job market is dynamic, and sometimes, a degree with a clear career path bes the safer bet. Fields like engineering, medicine, or finance offer stability and a predictable career trajectory. These majors provide students with the necessary skills and knowledge to enter lucrative industries, ensuring financial security and potentially afortable lifestyle.The dilemma then arises from the fear that passion might be overshadowed by the harsh realities of the real world. Thepressure to conform to societal expectations, financial responsibilities, and the need for immediate gratification can make the practical choice seem more appealing. Yet, the potential long-term regrets of forsaking one's true calling could weigh heavily.A balanced approach, therefore, seems the most viable solution. One can choose a major thatbines both passion and practicality. Many institutions now offer interdisciplinary programs that integrate theory with practical applications, allowing students to explore their interests while equipping them with employableskills. Alternatively, pursuing a passion initially and then seeking to pivot or specialize within the industry later can also be a strategy.Ultimately, the decision should rest on an individual's values, priorities, and aspirations. It is crucial to remember thatsuccess is not solely measured by salary or job title but also by personal fulfillment and happiness. Pursuing a major that aligns with one's heart may lead to a more meaningful career, even if it takes time to find its footing.In conclusion, the choice between a passion-driven major and a job-oriented one is a deeply personal one. While practical considerations are important, it is the spark of genuine interest that fuels the fire of innovation and progress. It is a journeythat requires self-reflection, resilience, and the courage tofollow one's dreams, regardless of the road ahead. After all, life is a canvas, and the choice of major is but one brushstroke in the masterpiece of our existence.示例作文篇二：Title: Pursuit of Passion or Practicality: The Choice of a Fulfilling Academic JourneyIn the labyrinth of life's decisions, one of the most daunting choices young minds face is selecting a major - a path that will shape not only their academic future but also their professional life. Should we choose a field that ignites our passion or opt for one with better job prospects? This question often prompts introspection and deliberation, a conundrum that echoes within countless hearts.On one hand, the allure of passion lies in its magnetic pull. It is the spark that drives us to explore, innovate, and push boundaries. Pursuing a subject we love, be it art, music, or science, brings a sense of intrinsic joy and satisfaction. We wake up eager to learn, and the hours spent studying seem like moments of play rather than labor. Such passion-driven majors foster creativity, critical thinking, and resilience, skills that can transcend any specific job market.However, the practical side cannot be overlooked. Intoday'spetitive world, a secure career often relies on fields with high demand and steady job prospects. Engineering, medicine, and technology, for instance, consistently rank among the top-paying and in-demand professions. Choosing such majors ensures financial stability and a tangible return on investment in terms ofeducation and time.The dilemma then bes a delicate balance between heart and head. Many argue that passion should guide our decisions, as it leads to a more fulfilling life. They contend that happiness derived from doing what one loves outweighs material gains. Others, however, advocate for a pragmatic approach, believing that securing astable livelihood should take precedence over personal fulfillment.I, too, am torn between these two ideologies. On one hand, I dream of immersing myself in a field where my curiosity can flourish, where every challenge is an opportunity to grow. But on the other hand, the thought of financial stability and the responsibility towards family beckons.Ultimately, I believe that the choice should be a synthesis of both. We must find a major that satisfies our passion while also providing realistic opportunities for growth and financial security. It may not be a clear-cut decision, but rather a continuous exploration and adaptation. Our education should be a journey of self-discovery, where we learn to navigate between our interests and the demands of the real world.In conclusion, the choice of a major is not a binary decision between passion and practicality, but a nuanced dance between the two. It is about finding the sweet spot where our love for learning meets the realities of the job market. After all, a fulfilling life is not solely about the destination, but also about the journey, the experiences, and the joy derived from pursuing what we truly love.示例作文篇三：Title: Pursuit of Passion or Practicality: The Choice of a Fulfilling MajorIn the labyrinth of life's decisions, one of the most crucial milestones for a student is choosing a major that will shape their future trajectory. The eternal debate rages on: should one opt for a passion-driven course or a job-oriented major? This conundrum often leaves young minds grappling with the weight of personal fulfillment against financial stability.On one hand, the allure of a passion-based major is undeniablypelling. It is the pursuit of what ignites the soul, the subject that whispers, "this is where you belong." Imagine immersing oneself in the realm of art, science, or literature, driven solely by the love for it. Such an education promises alife rich in intellectual exploration, fostering creativity and critical thinking skills. It is a journey that can lead to a sense of purpose, a fire that burns brighter than any résumé.However, the practical side cannot be ignored. The reality of the job market demands skills that are in demand, majors thatoffer a clear career path and potential financial security. Engineering, medicine, business, and technology - these majors, though often seen as less romantic, provide tangible opportunities for employment and growth. They offer a safety net, ensuring that one's hard work translates into a stable ie and a predictable future.The choice between the two is not a black-and-white affair but a nuanced dance between heart and head. It is about striking a balance between personal fulfillment and professional viability. One must remember that passion does not always guarantee success, and practicality does not guarantee happiness. It is possible to find a major thatbines both, allowing for a fulfilling career in a field one loves.A wise approach would be to conduct thorough research, understanding the intersection between personal interests and market trends. Internships, part-time jobs, and informational interviews can provide valuable insights into the real-world implications of various majors. It's essential to consider the long-term prospects and the potential for personal growth, rather than just focusing on immediate job prospects.Ultimately, the decision should stem from a place of self-awareness and understanding. It's about identifying what truly motivates and drives you, while also acknowledging the practical considerations of the world outside academia. Remember, the choice of a major is not a final destination, but a stepping stone on a lifelong journey of learning and self-discovery.In conclusion, the pursuit of passion or practicality is not a zero-sum game. Both aspects have their value, and the key lies in finding the sweet spot that aligns your heart and mind. Embrace the challenge, make a well-informed decision, and trust that the right path will reveal itself, leading you to a fulfilling and prosperous life.示例作文篇四：Title: Pursuit of Passion or Practicality: A Student's DilemmaIn the labyrinth of life's decisions,高中生们 often find themselves at a crossroads when ites to choosing a major - should they follow their heart and pursue their passions, or opt for a field that promises better job prospects? This question, fraught with anticipation and anxiety, is a rite of passage for many young minds.The allure of passion lies in its magnetic pull, the sparkthat ignites an insatiable curiosity and a desire to delve deep into a subject. It's the love for art that fuels the painter's strokes, the thrill of science that propels the inventor forward. Pursuing a passion, one could argue, leads to a more fulfilling life, as it allows individuals to cultivate a unique identity and contribute to society through their authentic work.On the other hand, the practical side of the argument cannot be ignored. In today'spetitive job market, choosing a major with high employability rates can provide financial security and stability. Engineering, medicine, and business, for instance, are often cited as fields with promising career prospects and relatively lower unemployment rates. These majors offer a clear roadmap, enabling graduates to navigate the professional world with confidence.The dilemma, however, is not a binary choice between passion and pragmatism. It is about finding a balance, a middle ground where both interests can coexist. One could choose a major thatbines their personal passions with practical skills, ensuring a harmonious blend of fulfillment and stability. For instance, a graphic designer who also acquires strong business management skills would have a unique advantage in the industry.Moreover, it is important to remember that success is not solely defined by employment statistics. Many successful individuals have embarked on careers that initially seemed unrelated to their passions, but their relentless pursuit of what they loved eventually led them to innovative and impactful work. The key lies in resilience, adaptability, and the willingness to learn and grow.In conclusion, the decision to choose a major should not be driven solely by fear or ambition, but rather by a thoughtful consideration of personal inclinations, future aspirations, and the potential for growth. Passion should guide us, but we must also be realistic about the practical implications of our choices. After all, life is a journey, and the true reward lies not only in the destination but also in the experiences and lessons learned along the way. As students, we must dare to dream big while being grounded in reality, for that is the path to a well-lived, meaningful life.示例作文篇五：Title: The Pursuit of Passion or Practicality: A Student's DilemmaIn the vast landscape of academic choices, a student stands at a crossroads, faced with an eternal question - should they pursue their passion or opt for a career-oriented major? This decision, though daunting, is a pivotal one that shapes not only their academic journey but also their future trajectory.On one hand, the allure of passion lies in its ability to ignite a fire within. It is the spark that drives us to delve deep into subjects that ignite our curiosity and imagination. When we study what we love, hours of learning be moments of pure joy. The intrinsic motivation propels us through challenges and setbacks, turning them into stepping stones towards mastery. Pursuing a passion, be it art, science, or literature, allows for personal growth and fulfillment beyond the confines of a job market.However, the practical side cannot be ignored. Intoday'spetitive world, securing a well-paying job often relies on choosing a field with high demand and job stability. Engineering, medicine, and technology are examples of majors that offer lucrative opportunities and potential for long-term career security. These fields may not always align with one's passion, but they provide a solid foundation for financial independence and materialfort.The dilemma arises when we weigh the satisfaction of pursuing a dream against the pragmatism of a secure future. Some argue that passion should guide our decisions, as it fosters creativity and innovation, essential for societal progress. They contend that if one can find a way to make a living doing what they love, theywill be more likely to excel and contribute positively.On the other hand, proponents of practicality emphasize that financial stability and job security are crucial aspects of life. They argue that while passion is important, it should not overshadow the need for financial stability, especially in light of economic uncertainties and the need to support oneself and loved ones.Ultimately, the choice between passion and practicality is a deeply personal one. It requires introspection, understanding of one's priorities, and realistic expectations. It is about finding a balance, perhaps a middle ground where one can pursue a subject they are passionate about while also ensuring a sustainable career path.For me, the ideal scenario would be to strike a harmonious blend. I would seek a major thatbines my interests with marketability, allowing me to pursue my passions while preparing for the professional world. This way, I can nurture my creativity while having the reassurance of a stable future.In conclusion, the decision to choose a passion-driven or job-oriented major is not a black-and-white issue. It is a nuanced exploration of self-discovery and the pursuit of a fulfilling life. As a student, I believe that it is possible to find a path that satisfies both the heart and the head, and that is the truevictory in this lifelong journey of learning and growth.示例作文篇六：Title: The Dance of Passion and Practicality: A Quest for the Ideal MajorIn the labyrinth of life's decisions, one of the most pivotal choices we confront as students is the selection of a major.Should we pursue our heart's desire, embarking on a journey of passion, or should we prioritize job prospects, securing a promising future? This conundrum, a delicate balance between personal fulfillment and practicality, is a nuanced dance thateach of us must learn to navigate.The allure of passion lies in its ability to ignite a fire within us. It is the spark that drives us to explore, to question, and to relentlessly pursue knowledge. When we choose a major that aligns with our passions, we embark on a path of intrinsic motivation. Our learning bes a joy, not a chore. We wake up eager to engage with our subjects, turning every challenge into an opportunity for growth. However, the path of passion is often uncharted, with potential uncertainties and financial risks.On the other hand, the pursuit of a job-secure major seems more pragmatic. It promises a clear career trajectory, steady ie, and a sense of stability. These majors, often rooted in fieldslike engineering, medicine, or business, provide a solid foundation for a successful professional life. They cater to the practical needs of society, ensuring a direct link between education and employability.The decision between the two is not a black-and-white one.It's a spectrum, a blend of both. Ideally, one would wish for a major thatbines their passion with employability. A field that allows them to utilize their skills while pursuing their interests. This is where the concept of 'career happiness'es into play. It is the sweet spot where personal fulfillment meets professional success.Many argue that passion should precede practicality, citingthe potential for innovation and groundbreaking discoveries.History has shown that groundbreaking minds often emerged from unconventional paths, driven by their relentless curiosity. Yet, others contend that practicality should be the guiding light, emphasizing the importance of financial stability and job security.Ultimately, the choice should be a reflection of one's priorities, values, and aspirations. It's about finding the right balance between the excitement of exploring the unknown andthefort of a secure future. While it may seem daunting at first, this decision is not set in stone. It's a journey that can change, evolve, and adapt over time.In conclusion, the quest for the ideal major is not just about choosing a degree, but a lifelongmitment to self-discovery and growth. It's about striking a chord between the vibrant melody of passion and the steady rhythm of practicality. Remember, a well-lived life is abination of both, a harmonious blend of dreams and reality, where the heart and head dance together in perfect harmony.示例作文篇七：Title: Pursuing Passion or Pragmatism: A Tug of War between Interests and Job ProspectsIn the vast landscape of higher education, students often find themselves at a crossroads, faced with the daunting decision of choosing a major that aligns with their passions or one that promises better job prospects. This conundrum is not unique to any era, yet it continues to spark intense debates among young minds. As a student myself, I believe this choice is not a zero-sum game but a delicate balance between personal fulfillment and practicality.To begin with, the allure of pursuing a passion lies in its intrinsic motivation. It's the spark that ignites our curiosityand keeps us engaged even during challenging times. When we study something we love, the learning process bes an adventure, not a chore. For instance, a student with a passion for art might choose Fine Arts, despite the potential financial uncertainties, because the joy derived from creating and expressing oneself is invaluable.However, the argument for practicality cannot be dismissed. In today'spetitive job market, choosing a major with strong employability can provide a safety net. Fields such as engineering, medicine, or business management offer clear career paths and lucrative opportunities. The thought of securing a stable future and supporting oneself or family is apelling factor for many.The tug-of-war between these two extremes often leads to introspection and self-discovery. It's crucial to understand that one does not have to sacrifice one for the other. Manyinstitutions now offer interdisciplinary programs, allowing students to merge their interests with practical skills. For example, a student passionate about sustainability could major in Environmental Science and Management,bining their love for nature with the knowledge needed for a green career.Moreover, the ability to adapt and learn is a valuable skillin today's rapidly changing world. Even in a seemingly "practical" major, there's room for creativity and personal growth. Conversely, a well-versed individual in a less conventional field can often surprise employers with their innovative approach and entrepreneurial spirit.Ultimately, the decision should stem from a deep understanding of oneself. Are you more driven by the thrill of discovery or the security of a steady ie? It's essential to consider both short-term and long-term goals, acknowledging that life is a series of choices that lead to a cumulative oue.In conclusion, the pursuit of passion or job prospects is not a dichotomy, but rather a harmonious blend. While passion provides the fire within, practicality serves as the solid foundation. As I navigate my academic journey, I strive to strike a balance between the two, knowing that true success lies in finding a path that satisfies both my heart and my head. After all, the mostfulfilling careers are those that marry our interests with the realities of the world we inhabit.示例作文篇八：Title: Pursuing Passion or Practicality: A Thought-Provoking JourneyIn the labyrinth of life's decisions, students often find themselves at a crossroads, contemplating the choice between selecting a major that ignites their passion or one that promises better job prospects. This conundrum is not unique to any era, yet it remains a timeless question that echoes in the hearts of young minds. The debate between passion and practicality is a nuanced dance, each step carrying its own weight of fulfillment and future security.On one hand, the allure of a passion-based major is undeniable. It is the pursuit of what captivates our hearts, the subjects that make us lose track of time. It is the spark that ignites a fire within, turning mundane hours into moments of creative explosion.A degree in literature, for instance, allows one to delve into the depths of human emotions, while a passion for science can lead to groundbreaking discoveries. The joy of learning for the sake of knowledge, the thrill of creation, these are the intangiblerewards that such majors offer.However, the specter of practicality looms large. Intoday'spetitive job market, a major that guarantees employability often holds more sway. Fields like engineering, business, and healthcare, for example, are in high demand due to their direct applicability to real-world problems. The promise of a stable salary, benefits, and career growth can provide a sense of financial security, a foundation upon which dreams are built.The decision, then, is not an either-or proposition. It is a delicate balance between the heart and the head. One must consider the potential for personal fulfillment against the practical realities of life. Passion should not be dismissed as frivolous; it can serve as a driving force, inspiring creativity and resilience in the face of challenges. On the other hand, practicality ensures that one's skills align with the demands of the world, increasing the likelihood of success.Ultimately, the choice should be made with a clear understanding of oneself. What点燃 your soul? What kind of impact do you wish to make? Are you seeking a life filled with purpose or one where financial stability is paramount? It is crucial to remember that a well-rounded education, regardless of the major, can equip one with the necessary skills to navigate both worlds.In conclusion, the choice between passion and practicality is a deeply personal one. It requires introspection, courage, and a willingness to embrace the unknown. Remember, a life well-lived is not solely about the destination but also about the journey, the experiences, and the joy derived from pursuing what truly matters. So, embark on this path with a heart full of enthusiasm, armed with the knowledge that both passion and practicality can coexist, leading to a fulfilling and prosperous future.。

中英文对照资料外文翻译文献附录Ⅰ：Magnetoelastic Torque Sensor Utilizing a Thermal Sprayed Sense-Element for Automotive Transmission ApplicationsABSTRACTA Magnetoelastic based Non-Contacting, Non-Compliant Torque Sensor is being developed by Siemens VDO for automotive transmission applications. Such a sensor would benefit the automotive industry by providing the feedback needed for precise computer control of transmission gear shifting under a wide range of road conditions and would also facilitate cross-platform usage of a common transmission unit.Siemens VDO has prototyped transmission torque sensors operating on the principle of Inverse- magnetostriction, also referred to as the Inverse-Joule Effect and the Villari Effect. Magnetostriction, first documented in the mid 1800’s, is a structural property of matter that defines a material’s dimensional changes as a result of exposure to a magnetic field. Magnetostriction is caused when the atoms that constitute a material reorient in order to align their magnetic moments with an external magnetic field. This effect is quantified for a specific material by its saturation magnetostriction constant, which is a value that describes a material’s maximum change in length per unit length.Inverse-magnetostriction, conversely, defines changes in a material’s magnetic properties in response to applied mechanical forces. Material that is highly magnetostrictive and elastic in nature is referred to as being magnetoelastic. The premise of the Siemens VDO torque sensor design is that a magnetoelastic material can be bonded to a cylindrical shaft and magnetized in its mechanical quiescent state to create a sense- element. While under torque, principle tensile and compressive stress vectors in the form of counter- spiraling, mutually orthogonal helices develop in the shaft and are conveyed to the magnetoelastic sense-element giving rise to a measurable magnetic field change. The magnetic field deviation that arises from the magnetoelastic sense-element is directly proportional to the magnitude of the imposed torque. In effect, the magnetic field is modulated by torque. A sensitive magnetometer then translates the field strength into an analog voltage signal, thereby completing the torque-to-voltage transducer function.Critical to the success of the Siemens VDO torque sensor design is an intimate attachment of the sense- element to the torque-bearing member. Inconsistencies in the boundary between the sense-element and the torque-bearing member will result in aberrant coupling of stresses into the sense-element manifesting in performance degradation. Boundary inconsistenciescan include such imperfections as voids, contaminates, lateral shearing, and localized zones of stress pre-load. Such inhomogeneities may be inherent to an attachment method itself or may subsequently be caused by systemically rendered malformations.Thermal spray, the process where metal particles are deposited onto a substrate to form a coating, was used to address the issue of securely affixing magnetic material to a torque-bearing member. In addition to achieving the prerequisite of an intimate and secure bond, the thermal spray process can be regulated such that the deposited magnetic material is pre-loaded with the internal stresses needed to invoke the inverse- magnetostriction effect.Summarizing, the passive nature of the magnetic sense- element provides an intrinsically simple kernel for the Siemens VDO torque sensor that makes for a highly reliable and stable design. The thermal spray process adds robustness to the mechanical aspect by permitting torque excursions to an unprecedented ±2000% of full scale (per prototype validation testing of certain constructs) without the need for ancillary torque limiting protection devices. Furthermore, accuracy, repeatability, stability, low hysteresis, rotational position indifference, low cost and amenability to the high-volume manufacturing needs of the automotive marketplace are all attributes of this torque sensing technique. When coupled with a magnetometer that is grounded in well- established fluxgate technology, the resultant sensor is inherently dependable and can potentially establish a new standard for torque measuring sensors.INTRODUCTIONAs is well known, automotive transmissions are designed to alter the power transfer ratio between the engine and the drive wheels effectively optimizing engine loading. The engine thereby runs in a narrow and efficient operating band even though the vehicle travels over a wide range of speeds. For automatic transmissions, shift valves select the gear ratio based generally on the throttle position, engine vacuum and the output shaft governor valve state. With the advent of electronic sensors and computerized engine controllers, transmission shift functions have been migrating towards closed-loop operation under software processing control. Along with this progression came the realization that the transmission output torque would provide a valuable feedback parameter for shift and traction control algorithms. The measurement of output torque, however, proved elusive due to the extremely harsh operating conditions. One particular SUV application under consideration required 1% accuracy in measurements of roughly 2700 Nm with possible torque excursion of 4700 Nm; all while exposed to temperature extremes -45 to +160 o C.One method for measuring torque is to examine the physical stresses that develop in a shaft when it is subjected to an end-to-end twisting force. The principle stresses are compressive and tensile in nature and develop along the two counter-spiraling, mutually orthogonal 45 o helices. They are defined by the equation :t = Tr / JWhere T is the torque applied to the shaft, r is the shaft radius and J is the polar moment of inertia.Setting p r4/ 2 = J for a solid cylindrical shaft and r = d/2 yields:t = 16T / p dOnce again, T is the torque applied to the shaft and d is the shaft diameter.Furthermore, the degree of twist experienced by the shaft for a given torque is given by2: q = 32(LT) / (p d4G)Where L is the length of the shaft, T is the applied toque, d is the diameter of the shaft and G is the modulus of rigidity of the shaft. The modulus of rigidity defines the level of elasticity of the shaft material, thus, a lower G value would manifest in a shaft with a higher degree of twist for any given applied torque.Torque induced stresses that occur in the shaft material are transferred into an affixed magnetic coating and give rise to measurable changes in its surrounding magnetic field that are directly proportional to the magnitude of the applied torque; with the polarity of the magnetic field, i.e., north or south, governed by the direction of the applied torque. In essence, this is the premise of torque sensing by means of inverse magnetostriction.TORQUE SENSOR EMBODIMENTTo effectively invoke the inverse-magnetostriction effect, the magnetic material must be correctly pre-loaded with stress anisotropy in its quiescent state. In the case of a cylindrically shaped magnetic element, the anisotropic forces must be circumferential (i.e., tangential) in nature and can be either compressive or tensile –depending on the polarity or sign of the material’s saturation magnetostriction constant. Achieving a homogenous pre-load throughout the magnetic material is crucial if the sensor is to accurately interpret torque regardless of its rotational position within a stationary magnetometer.POSITIVE MAGNETOELASTIC DEVICESEarlier efforts to create such a torque sensing element relied on a sense element made of material with a positive saturation magnetostriction constant. This embodiment was realized with a ring-shaped magnetoelastic element made from 18% nickel-iron alloy that intrinsically requires tensile circumferential pre- loading 3 . Such a pre-load was achieved by pressing the ring onto a tapered area of the base shaft – effectively stretching it. The effect of tensile stress on the magnetic hysteresis behavior is shown in Figure 1 where the remnant inductance, B r , nearly triples. The “easy-axes” of the magnetic domains align circumferentially due to the anisotropy defined by the principal tensile stress vector. When magnetically biased, the system in effect operates as a circumferentially shorted magnet with B approaching B r and H approaching zero.NEGATIVE MAGNETOELASTIC DEVICESTo advance the state of the art, Siemens VDO Automotive has opted for a magnetoelastic element witha negative saturation magnetostriction constant. In this case, the alloy is very high in nickel content exhibiting a saturation magnetostriction, l s , in the range of -3e-5 dl/l and requires the stress pre-load to be tangentially compressive in nature. To achieve this embodiment, the magnetoelastic material that constitutes the sense element is “deposited” onto the base shaft using a high- velocity-oxygen-fuel (HVOF) thermal spray process. The coating thickness is only 0.5mm with an axial length of 25mm. The sense element material is endowed with compressive stress by means of precise control of the thermal spray process parameters. This proprietary procedure transforms a deposition process that normally confers isotropic material properties into one that renders the requisite stress anisotropy.Prototype FabricationMagnetoelastic ElementThe specification for the shaft requires the measurement of torque levels of 2700 Nm with no deleterious effects following exposures of up to 4700 Nm. Operating temperature is -45 o C to 160 o C.By converting from the earlier torque sensor “pressed-on ring” concept to one based on a magnetoelastic material with a negative saturation magnetostriction constant, l s , the design is advanced in several respects. Primarily, its resiliency against stress/corrosion cracking is enhanced by 1) the inherent insusceptibility of high nickel content alloys towards corrosives and 2) by the lower porosity of material in compression. This is in distinct contrast with the high iron content ring placed in tension which is vulnerable to fissuring, material creep and stress corrosion cracking which can, over time, relieve the necessary anisotropic forces causing performancedegradation.An important consequence of using the thermal spray technology is the intimate bond provided between the deposited magnetoelastic element and the base shaft. By using a thermal spray process, the boundary whereby torque induced stresses are transferred is free of such imperfections as voids, galled or furrowed material and localized stress gradients that are all characteristically associated with the pressed-on ring technique. These imperfections can induce aberrations in the magnetic field shape thereby imparting torque measurement errors relative to the rotational position of the shaft with respect to a stationary magnetometer. Furthermore, the strong bond at the interface effectively eliminates the slippage commonly associated with the interference fit of a pressed-on ring during extreme torque exposures. Any movement at this interface will manifest as a biasing of material stresses causing a zero-shift measurement error. This is not a concern when the magnetoelastic element is deposited using an HVOF thermal spray gun. Torque excursions to an unprecedented ±2000% of full scale have been successfully applied directly to prototype sensors without ancillary torque limiting protection devices.In addition, depositing the magnetoelastic element onto a rotating shaft provides an inherently mechanically balanced assembly that imposes no angular velocity (RPM) or angular acceleration limits on the system.Other thermal spray technology attributes are its amenability to high volume manufacturing environments, the robustness of the process insuring consistent reproducibility, and an overall reduction in fabrication steps –such as the elimination of machining procedures to mass-produce rings, cutting operations for precisely matching tapers on the shaft and ring, and pressing operations to install rings onto shafts.Magnetic Field ShapingContributions from the mechanical mounting tolerances of system components (e.g., bearings and bushings) can manifest as a misalignment between the centroid centerlines of the magnetometer and the magnetoelastic element. Once calibrated, any displacement in the positional relationship between these two components will alter the system’s transfer function, possibly causing the overall error to exceed specification. The sharply focused nature of the magnetic field radially emanating from the magnetoelastic element during the application of torque (see Figure 3) accentuates this effect. This error can be minimized by shaping the physical structure of the magnetoelastic element resulting in a contouring of the magnetic field to a more favorable shape. As shown in Figure 4, the magnetic field is made to be less pronounced with an hourglass shaped magneto elastic element and sensitivity to misalignment is, thus, reduced. In this example, the magneto elastic element is contoured such that the air gap between the magneto elastic element and the magnetometer is reduced when axial displacement between their centroid centerlines occurs. The expected reduction in magnetic signal strength caused by this displacement is thus compensated by the air gap reduction.Shafts can be fabricated with a variety of contoured surface adaptations and the thermal sprayed magnetoelastic element’s shape will expectedly follow suit. As is evident, a pressed-on ring manifestation of the magnetoelastic element would be incompatible with this technique. Various contours are being considered for further reducing the sensitivity to misalignment and for improving other performance parameters such as magnetic field strength and hysteresis.Cylindrical Shaft Shown with Superimposed Associated Magnetic Field (i.e., Radially Directed Flux Density)Contoured Shaft (Hourglass Shape) Shown with Superimposed Associated Magnetic Field (i.e., Radially Directed Flux Density)In Figures 3 and 4, the spatial image of the shaft is mapped using a laser displacement system and the superimposed magnetic field is mapped in 3-space with a hall cell.MagnetometerRounding out the torque sensor hardware complement is a non-contacting magnetometer that translates the magnetic signal emitted by the shaft’s sense element into an electrical signal that can be read by system-level devices. Coupling the torque signal to some interim conditioning electronics magnetically is an attractive option due to its “non-contacting” attribute. A signal transference scheme capable of spanning an air gap is advantageous sinceit requires no slip rings, brushes or commutators that can be affected by wear, vibration, corrosion or contaminants.The fundamental magnetometer embodiment, shown in Figure 5, is circular with the shaft passing through its center. The magnetometer encompasses the magnetoelastic element of the shaft and the shaft is allowed to freely rotate within the fixed magnetometer. Power and the output signal pass through the magnetometer’s wiring harness.Transmission Torque Sensor MagnetometerThe magnetometer actually performs several functions beyond measuring a magnetic field’s strength. These functions include magnetic signal conditioning, electrical signal conditioning, implementation of self-diagnostics, and the attenuation of magnetic and electromagnetic noise sources.The magnetic detection method chosen for the torque sensor is fluxgate magnetometry, also known as saturable-core magnetometry. This is a well-established technology that has been in use since the early 1900’s. Fluxgate ma gnetometers are capable of measuring small magnetic field of strengths down to about 10 -4 A/m (or 10 -6 Oe) with a high level of stability. This performance is roughly three orders of magnitude better than that achieved by Hall Effect devices. Although many fluxgate designs use separate drive and pickup coils, the torque sensor magnetometer was designed to use a single coil for both functions.Magnetic signal conditioning is accomplished by use of flux guides integral to the magnetometer. These flux guid es amplify the magnetic signal radiating from the shaft’s sense element prior to detection by the fluxgates thereby improving the signal-to-noise ratio. The flux guides provide additional signal conditioning by integrating inhomogeneities in the magnetic signal relative to the shaft rotational position that might otherwise be misinterpreted as torque variations. The flux guide configuration is shown in Figure 6 and a magnetic simulation of the resulting field concentration is shown in Figure 7.Flux guides surrounding magnetoelastic elementAxial view of magnetic simulation with flux guide material’s relative DC permeability set to 50,000 (e.g., HyMu “80”)To further improve the magnetometer’s immunity to stray signals present in the ambient, common-mode rejection schemes are employed in the design of both the electronic and magnetic circuits. For example, wherever possible, differential circuitry was used in theelectronic design in order to negate common-mode noise. This practice was carried over to the magnetic design through the use of symmetrically shaped flux guides and symmetrically placed fluxgates that cancel common- mode magnetic signals that originate outside the system.Finally, to augment the electrical and magnetic common- mode rejection strategies, EMI and magnetic shielding practices were incorporated into the design to further improve the signal-to-noise ratio. Stray magnetic and electro-magnetic signals found in the ambient are prevented from reaching the fluxgates and the shaft’s magnetic torque-sensing element through the use of shielding material that encompasses these critical components.The functional diagram of Figure 8 depicts the concept of the magnetometer by showing a simplified version of the circuitry with extraneous components removed for additional clarity. An application specific integrated circuit (ASIC) contains all the circuitry necessary to perform the indicated functions.Magnetometer Functional DiagramSummarizing, the multi-function, fluxgate based magnetometer design provides the optimal platform for detecting the modulated magnetic field that emanates from the shaft’s torque-sensing magnetic element. By coupling time-proven fluxgate technology with an innovative flux guide configuration and with sophisticated electronic circuitry, the resultant magnetometer is durable, accurate, and stable and comprehensively achieves the design goals dictated by the application.CONCLUSIONThe latest developments in the magnetoelastic torque sensor that are presented here advance the current state of the technology by addressing many obstacles that have delayed itsacceptance by the automotive industry. Thermal spray deposition of the magnetoelastic element has resolved problems that have plagued earlier versions of the magnetoelastic torque sensor’s active element. The lack of integrity of the shaft/magnetoelastic element interface, stress-corrosion cracking, long term stability, inhomogeneity of magnetic properties and manufacturing processes that run counter to high volume production, are no longer hindering the introduction of magnetoelastic torque sensors into the automotive marketplace. With design goals clearly defined and an aggressive development program invariably progressing, the prospect of an automotive, magnetoelastic based non-compliant torque sensor is now more readily attainable.ACKNOWLEDGMENTSI would like to acknowledge the efforts of Ivan Garshelis who pioneered this approach to torque sensing and who had the unwavering vision to recognize this technology’s potential; and Carl Gandarillas whose scientific and analytical investigative approach has explicated much of the mystery associated with thermal sprayed magnetics. I would also like to express my gratitude to the torque sensor development team at Siemens VDO Automotive for their dedication and the extra effort that they put forth; and to Siemens VDO Automotive management for having the courage to invest in a new technology and the patience to see it through.REFERENCES1. Raymond J. Roark and Warren C. Young, Formulas for Stress and Strain, 5 th Edition, McGraw-Hill; Chapter 9, Torsion2. Stephen H.Crandall and Norman C. Dahl, An Introduction to the Mechanics of Solids, McGraw-Hill; Chapter 6, Torsion3. Ivan J. Garshelis, Magnetoelastic Devices, Inc., IEEE Transaction On Magnetics ; 0018-9464/92 V ol. 28, No. 5 September 5, 1992ADDITIONAL SOURCES1. Richard L. Carlin, Magnetochemistry; Springer-Verlag2. Rollin J. Parker, Advances In Permanent Magnetism; John Wiley & Sons3. Etienne du Tremolet de Lachhesserie, Magnetostriction Theory and Applications of Magnetostriction; CRC Press4. Richard M. Bozorth, Ferromagnetism; IEEE Press附录Ⅱ：磁力矩传感器利用一个热喷涂感知元件在汽车变速器中的应用摘要一个非接触式的，非兼容扭矩的传感器是由西门子VDO正在开发应用于汽车传动之中。