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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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Theoretical characterization of the temperature-dependent saturation magnetization of magnetic metallic materials
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作者 吴金龙 董攀 +6 位作者 贺屹 马艳丽 李梓源 姚沁远 邱俊 麻建坐 李卫国 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期577-585,共9页
Based on the force-heat equivalence energy density principle,a theoretical model for magnetic metallic materials is developed,which characterizes the temperature-dependent magnetic anisotropy energy by considering the... Based on the force-heat equivalence energy density principle,a theoretical model for magnetic metallic materials is developed,which characterizes the temperature-dependent magnetic anisotropy energy by considering the equivalent relationship between magnetic anisotropy energy and heat energy;then the relationship between the magnetic anisotropy constant and saturation magnetization is considered.Finally,we formulate a temperature-dependent model for saturation magnetization,revealing the inherent relationship between temperature and saturation magnetization.Our model predicts the saturation magnetization for nine different magnetic metallic materials at different temperatures,exhibiting satisfactory agreement with experimental data.Additionally,the experimental data used as reference points are at or near room temperature.Compared to other phenomenological theoretical models,this model is considerably more accessible than the data required at 0 K.The index included in our model is set to a constant value,which is equal to 10/3 for materials other than Fe,Co,and Ni.For transition metals(Fe,Co,and Ni in this paper),the index is 6 in the range of 0 K to 0.65T_(cr)(T_(cr) is the critical temperature),and 3 in the range of 0.65T_(cr) to T_(cr),unlike other models where the adjustable parameters vary according to each material.In addition,our model provides a new way to design and evaluate magnetic metallic materials with superior magnetic properties over a wide range of temperatures. 展开更多
关键词 magnetic metallic materials temperature dependent saturation magnetization MODELING
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Origin of Magnetic Fields of Stellar Objects in the Universe Based on the 5D Projection Theory
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作者 Peter C. W. Fung K. W. Wong 《Journal of Modern Physics》 2017年第4期668-746,共79页
Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D p... Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D projection. The origin of such rotation is the balance of the angular momenta of stars and that of positive and negative charged e-trino pairs, within a 3D &otimes;1D?void of the stellar object, the existence of which is based on conservation/parity laws in physics if one starts with homogeneous 5D universe. While the in-phase e-trino pairs are proposed to be responsible for the generation of angular momentum, the anti-phase but oppositely charge pairs necessarily produce currents. In the 5D to 4D projection, one space variable in the 5D manifold was compacted to zero in most other 5D theories (including theories of Kaluza-Klein and Einstein [3] [4]). We have demonstrated, using the Fermat’s Last Theorem [5], that for validity of gauge invariance at the 4D-5D boundary, the 4th space variable in the 5D manifold is mapped into two current rings at both magnetic poles as required by Perelman entropy mapping;these loops are the origin of the dipolar magnetic field. One conclusion we draw is that there is no gravitational singularity, and hence no black holes in the universe, a result strongly supported by the recent discovery of many stars with masses well greater than 100 solar mass [6] [7] [8], without trace of phenomena observed (such as strong gamma and X ray emissions), which are supposed to be associated with black holes. We analyze the properties of such loop currents on the 4D-5D boundary, where Maxwell equations are valid. We derive explicit expressions for the dipolar fields over the whole temperature range. We then compare our prediction with measured surface magnetic fields of many stars. Since there is coupling in distribution between the in-phase and anti-phase pairs of e-trinos, the generated mag-netic field is directly related to the angular momentum, leading to the result that the magnetic field can be expressible in terms of only the mechanical variables (mass M, radius R, rotation period P)of a star, as if Maxwell equations are “hidden”. An explanation for the occurrence of this “un-expected result” is provided in Section (7.6). Therefore we provide satisfactory answers to a number of “mysteries” of magnetism in astrophysics such as the “Magnetic Bode’s Relation/Law” [9] and the experimental finding that B-P graph in the log-log plot is linear. Moreover, we have developed a new method for studying the relations among the data (M, R, P) during stellar evolution. Ten groups of stellar objects, effectively over 2000 samples are used in various parts of the analysis. We also explain the emergence of huge magnetic field in very old stars like White Dwarfs in terms of formation of 2D Semion state on stellar surface and release of magnetic flux as magnetic storms upon changing the 2D state back to 3D structure. Moreover, we provide an explanation, on the ground of the 5D theory, for the detection of extremely weak fields in Venus and Mars and the asymmetric distribution of magnetic field on the Martian surface. We predict the equatorial fields B of the newly discovered Trappist-1 star and the 6 nearest planets. The log B?&minus;?log P graph for the 6 planets is linear and they satisfy the Magnetic Bode’s relation. Based on the above analysis, we have discovered several new laws of stellar magnetism, which are summarized in Section (7.6). 展开更多
关键词 5D Projection Theory Fermats Last Theorem Perelmans Mappings Self-Rotation Dipolar MAGNETIC FIELD of Stars LAWS of STELLAR Magnetism LAWS of STELLAR Angular Momentum MAGNETIC Bodes Law NON-EXISTENCE of Gravitational Singularity Semion State of Atoms in STELLAR Surface MAGNETIC Storm Planetary MAGNETIC FIELD Maxwell Equations at 4D-5D Boundary MAGNETIC Fields of the Trappist-1 System
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Theory of Electromagnetism and Gravity —Modeling Earth as a Rotating Solenoid Coil
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作者 Greg Poole 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期663-692,共30页
Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in ... Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in new understanding of the earth’s electrical system and gyroscopic rotation. The material makeup of the inner earth is better understood based on derived permeability and permittivity constants. The planet has been modeled as simple coils and then as a parallel impedance circuit which has led to fundamental insight into planetary speed control and RLC combination for Schumann Resonance of 7.83 Hz. Torque and Voltage Constants and the inverse Speed Constant are calculated using three methods and all compare favorably with Newton’s Gravitational Constant. A helical resonator is referenced and Schumann’s Resonant ideal frequency is calculated and compared with others idealism. A new theory of gravity based on particle velocity selector at the poles is postulated. Two equations are presented as the needed links between Faraday’s electromagnetism and Newtonian physics. Acceleration and Deceleration of earth is explained as a centripetal governor. A new equation for planetary attraction and the attraction of atomic matter is theorized. Rotation of the earth’s electrical coil is explained in terms of the Richardson effect. Electric power transfer from the sun to the planets is proposed via Flux Transfer Events. The impact of this evolving science of electromagnetic modeling of planets will be magnified as the theory is proven, and found to be useful for future generations of engineers and scientists who seek to discover our world and other planets. 展开更多
关键词 Ampere Biot-Savart CENTRIPETAL Acceleration CENTRIPETAL GOVERNOR Dynamo EARTH Einstein-de Haas Effect Electric Field Electromagnetism Flux Transfer Events GOVERNOR Control GRAVITY Gravitational CONSTANT Helical Resonator Lenz Law Lorentz Lightning Magnetic Field Motor CONSTANT Parallel Impedance Planet SPEED Control Schumann Resonance Richardson Effect Solenoid SPEED CONSTANT Solar Power System Torque CONSTANT Velocity Selector Voltage CONSTANT
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Saturation Magnetization and Law of Approach to Saturation for Selfformed Ionic Ferrofluids Based on MnFe2O4 Nanoparticles 被引量:2
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作者 林跃强 李建 +4 位作者 刘晓东 张廷珍 文榜才 张清梅 苗华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期325-330,I0002,共7页
The magnetization curves of MnFe2O4 nanoparticles and self-formed ferrofluids based on these particles have been measured at room temperature. The median size of the particles is 13.67 nm. The specific saturation magn... The magnetization curves of MnFe2O4 nanoparticles and self-formed ferrofluids based on these particles have been measured at room temperature. The median size of the particles is 13.67 nm. The specific saturation magnetization is less than the theoretical value for the ferrofluids. In the high field range from 5 kOe to 10 kOe, the higher the particle volume fraction is, the steeper the slope of the magnetization curves is when it approaches saturation. The behavior of the saturation magnetization and the law of approach to saturation are due to the presence of self-assembled aggregates of ring-like micelle structures which form in the absence of the magnetic field and field-induced aggregates, respectively. The field-induced aggregates have a dissipative structure, so that at high field, the law of approach to saturation magnetization is different from the one described using Langevin paramagnetism theory. The large particles in the ferrofluids result in apparent hysteresis. 展开更多
关键词 NANOPARTICLE FERROFLUID Magnetic property AGGREGATE
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure Shell THEOREM 3D Computer Model Quantum
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Absolute Internal Energy of the Real Gas 被引量:1
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作者 Albrecht Elsner 《Engineering(科研)》 2017年第4期361-375,共15页
The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations am... The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations among gas temperature T, pressure p and mass-specific volume v=V/M, the mass exists as a uniform gas of freely-moving particles having positive values U or as more or less structured matter with negative values U. In the regions U>0?above the critical point [Tc , pc , vc] it holds that p(T,v)>pc and v>vc, and below the critical point it holds that p(T,v)c and v>vv , where vv is the mass-specific volume of saturated vapor. In the adjacent regions with negative internal energy values Uc is the line of equal positive and negative energy contributions and thus represents a line of vanishing internal energy ?U=0. At this level along the critical isochor the ever present microscopic fluctuations in energy and density become macroscopic fluctuations as the pressure decreases on approaching the critical point;these are to be observed in experiments on the critical opalescence. Crossing the isochor vc from U>0 to UΔU>0 happens without any discontinuity. The saturation line vv also separates the regions between U>0 and U , but does not represent a line U=0. The internal-energy values of saturated vapor Uv and condensate Ui can be determined absolutely as functions of vapor pressure p and densities (M/V)v and (M/V)i , repectively, yielding the results Uiv, U=Ui+Uvc and U=Ui=Uv=0 at the critical point. Crossing the line Vv from U=Uv>0 to U=Uv+UiΔU=-Ui>0 to be removed from the particle system. The thermodynamic and quantum-mechanical formulations of the internal energy of a particle system only agree if both the macroscopic and microscopic energy scales have the same absolute energy reference value 0. Arguments for the energy reference value in the state of transition from bound to freely- moving particles in macroscopic classical and microscopic quantum particle systems are discussed. 展开更多
关键词 ENERGY Reference Value Zero in Microscopic and Macroscopic Particle Systems STATE of Transition from Bound to Freely-Moving Particles INTERNAL ENERGY Regions in the STATE Chart of Gas CRITICAL Point and CRITICAL Isochor Loci of VANISHING INTERNAL ENERGY CRITICAL OPALESCENCE BEC Calculation of INTERNAL Energies of Saturated Liquid and Vapor
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The Mathematical and Physical Theory of Rational Human Intelligence: Complete Empirical-Digital Properties;Full Electrochemical-Mechanical Model (Part I: Mathematical Foundations)
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作者 Leo Depuydt 《Advances in Pure Mathematics》 2013年第5期491-561,共71页
The design of this paper is to present the first installment of a complete and final theory of rational human intelligence. The theory is mathematical in the strictest possible sense. The mathematics involved is stric... The design of this paper is to present the first installment of a complete and final theory of rational human intelligence. The theory is mathematical in the strictest possible sense. The mathematics involved is strictly digital—not quantitative in the manner that what is usually thought of as mathematics is quantitative. It is anticipated at this time that the exclusively digital nature of rational human intelligence exhibits four flavors of digitality, apparently no more, and that each flavor will require a lengthy study in its own right. (For more information,please refer to the PDF.) 展开更多
关键词 Artificial INTELLIGENCE Boolean ALGEBRA Booles ALGEBRA Black Box Theories Brain Science Cognition Cognitive Science Digital MATHEMATICS Electricity and Magnetism J.-L. Lagrange and Partial Differential Equations J. C. Maxwells Theory of Electromagnetism Neuroscience Non-Quantitative and Quantitative MATHEMATICS Physics RATIONAL Human INTELLIGENCE COMPLETE Theory of RATIONAL Thought and Language
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Correlation of Blood Lactate and Mixed Venous Oxygen Saturation in Off-Pump CABG
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作者 Ganapathy Sambandam Kamalakkannan Ranjith Karthekeyan +4 位作者 Mahesh Vakamudi Sandeep Bangale Rajeshkumar Kodali Hemanand Nayagam Sushma Nandipati 《World Journal of Cardiovascular Surgery》 2014年第7期131-138,共8页
Aim: To evaluate the correlation of blood lactate and mixed venous oxygen saturation to predict outcome in off-pump coronary artery bypass grafting. Method: This is a randomized study including 30 patients. Blood lact... Aim: To evaluate the correlation of blood lactate and mixed venous oxygen saturation to predict outcome in off-pump coronary artery bypass grafting. Method: This is a randomized study including 30 patients. Blood lactate and mixed venous oxygen saturation were measured in 4 groups of patients—number of grafts, presence or absence of left main coronary artery disease, ejection fraction and serum creatinine. Blood samples were taken before induction, after grafting, on intensive care unit admission, 24 hours and 48 hours after surgery. The measured blood lactate and mixed venous oxygen saturation are compared to assess the outcomes in terms of duration of ventilation and intensive care unit stay. Results: The blood lactate and mixed venous oxygen saturation values increased post operatively but no statistically significant difference in three groups— number of grafts, left main coronary artery disease and ejection fraction. In serum creatinine group, the blood lactate value was found to be statistically significant after grafting in patients with creatinine <1.5 mg/dl, however, there was a significant disparity in numbers. Conclusion: Mixed venous oxygen saturation is a better predictor of morbidity than blood lactate in terms of intensive care unit stay in patients undergoing off pump coronary artery bypass grafting. 展开更多
关键词 OFF-PUMP Coronary Artery BYPASS Grafting Blood LACTATE Mixed VENOUS Oxygen saturation EJECTION Fraction DURATION of Ventilation DURATION of Intensive Care Unit Stay
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Saturation Estimation with Complex Electrical Conductivity for Hydrate-Bearing Clayey Sediments:An Experimental Study 被引量:1
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作者 XING Lanchang ZHANG Shuli +8 位作者 ZHANG Huanhuan WU Chenyutong WANG Bin LAO Liyun WEI Wei HAN Weifeng WEI Zhoutuo GE Xinmin DENG Shaogui 《Journal of Ocean University of China》 CAS CSCD 2024年第1期173-189,共17页
Clays have considerable influence on the electrical properties of hydrate-bearing sediments.It is desirable to understand the electrical properties of hydrate-bearing clayey sediments and to build hydrate saturation(S... Clays have considerable influence on the electrical properties of hydrate-bearing sediments.It is desirable to understand the electrical properties of hydrate-bearing clayey sediments and to build hydrate saturation(S_(h))models for reservoir evaluation and monitoring.The electrical properties of tetrahydrofuran-hydrate-bearing sediments with montmorillonite are characterized by complex conductivity at frequencies from 0.01 Hz to 1 kHz.The effects of clay and Sh on the complex conductivity were analyzed.A decrease and increase in electrical conductance result from the clay-swelling-induced blockage and ion migration in the electrical double layer(EDL),respectively.The quadrature conductivity increases with the clay content up to 10%because of the increased surface site density of counterions in EDL.Both the in-phase conductivity and quadrature conductivity decrease consistently with increasing Sh from 0.50 to 0.90.Three sets of models for Sh evaluation were developed.The model based on the Simandoux equation outperforms Archie’s formula,with a root-mean-square error(E_(RMS))of 1.8%and 3.9%,respectively,highlighting the clay effects on the in-phase conductivity.The fre-quency effect correlations based on in-phase and quadrature conductivities exhibit inferior performance(E_(RMS)=11.6%and 13.2%,re-spectively)due to the challenge of choosing an appropriate pair of frequencies and intrinsic uncertainties from two measurements.The second-order Cole-Cole formula can be used to fit the complex-conductivity spectra.One pair of inverted Cole-Cole parameters,i.e.,characteristic time and chargeability,is employed to predict S_(h) with an E_(RMS) of 5.05%and 9.05%,respectively. 展开更多
关键词 gas hydrate complex electrical conductivity hydrate-bearing clayey sediment hydrate saturation Simandoux equation frequency dispersion Cole-Cole formula
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Numerical Analysis of the Magnetization Behavior in Magnetic Resonance Imaging in the Presence of Multiple Chemical Exchange Pools
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作者 Kenya Murase 《Open Journal of Applied Sciences》 2017年第1期1-14,共14页
The purpose of this study was to demonstrate a simple and fast method for solving the time-dependent Bloch-McConnell equations describing the behavior of magnetization in magnetic resonance imaging (MRI) in the presen... The purpose of this study was to demonstrate a simple and fast method for solving the time-dependent Bloch-McConnell equations describing the behavior of magnetization in magnetic resonance imaging (MRI) in the presence of multiple chemical exchange pools. First, the time-dependent Bloch- McConnell equations were reduced to a homogeneous linear differential equation, and then a simple equation was derived to solve it using a matrix operation and Kronecker tensor product. From these solutions, the longitudinal relaxation rate (R1ρ) and transverse relaxation rate in the rotating frame (R2ρ) and Z-spectra were obtained. As illustrative examples, the numerical solutions for linear and star-type three-pool chemical exchange models and linear, star- type, and kite-type four-pool chemical exchange models were presented. The effects of saturation time (ST) and radiofrequency irradiation power (ω1) on the chemical exchange saturation transfer (CEST) effect in these models were also investigated. Although R1ρ and R2ρ were not affected by the ST, the CEST effect observed in the Z-spectra increased and saturated with increasing ST. When ω1 was varied, the CEST effect increased with increasing ω1 in R1ρ, R2ρ, and Z-spectra. When ω1 was large, however, the spillover effect due to the direct saturation of bulk water protons also increased, suggesting that these parameters must be determined in consideration of both the CEST and spillover effects. Our method will be useful for analyzing the complex CEST contrast mechanism and for investigating the optimal conditions for CEST MRI in the presence of multiple chemical exchange pools. 展开更多
关键词 Bloch-McConnell Equations MULTIPLE CHEMICAL EXCHANGE POOLS CHEMICAL EXCHANGE saturation TRANSFER (CEST) Magnetic Resonance Imaging (MRI) Amide Proton TRANSFER (APT) MRI Numerical Analysis
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Gas hydrate saturation from NGHP 02 LWD data in the Mahanadi Basin
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作者 Uma Shankar Pradeep Kumar Yadav +1 位作者 Sneha Devi Udham Singh Yadav 《Energy Geoscience》 EI 2024年第2期279-289,共11页
During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock p... During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area A.We applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and NGHP-02-13.Rock physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this site.Saturation of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic log.However,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of hydrate.At site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 mbsf.Site NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 mbsf.Site NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 mbsf.Combined observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the Mahanadi Basin in the turbidite channel system. 展开更多
关键词 Mahanadi Basin Gas hydrate Sonic log Effective medium modeling Electrical resistivity log Archies analysis Gas hydrate saturation
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过渡金属取代的钨铝杂多配合物的制备、表征和性质
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作者 苏占华 徐学勤 +2 位作者 马慧媛 唐晓梅 周百斌 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第5期647-652,共6页
用分步设计法合成了以铝为中心原子的过渡元素与钨的三元杂多配合物,经ICP、TG分析确定其化学式为K4,6,7[AlM(OH2)W11O39]·xH2O(M=V5+、Cr3+、Mn2+、Fe3+、Co2+、Ni2+、Cu2+、Zn2+、Cd2+)。采用IR、UV、XRD、183W和27AlNMR等对配... 用分步设计法合成了以铝为中心原子的过渡元素与钨的三元杂多配合物,经ICP、TG分析确定其化学式为K4,6,7[AlM(OH2)W11O39]·xH2O(M=V5+、Cr3+、Mn2+、Fe3+、Co2+、Ni2+、Cu2+、Zn2+、Cd2+)。采用IR、UV、XRD、183W和27AlNMR等对配合物的结构进行了表征,表明配合物具有Keggin结构;循环伏安法对该系列配合物的氧化还原性质研究表明,其氧化还原过程为不可逆的两电子还原,配合物的磁化率测试均表现为顺磁性,还对其热稳定性进行了讨论。 展开更多
关键词 Keggin Cr^3%PLUS% Mn^2%PLUS% Fe^3%PLUS% CO^2%PLUS% Ni^2%PLUS% Cu^2%PLUS% Zn^2%PLUS% ^27AL ICP XRD NMR
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人脑初级体感皮质M_(20)反应的性别差异-脑磁图研究
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作者 孙吉林 李素敏 +3 位作者 吴杰 吴晶 赵华东 尹岭 《现代电生理学杂志》 2005年第2期68-71,共4页
目的:应用脑磁图(MEG)研究健康受试者初级体感皮质反应M20的潜伏期、波幅及位置的性别差异。方法:对40例受试者给予双侧腕部正中神经电刺激,固定电流脉冲0.3ms,刺激间期0.5s,诱发初级体感皮质兴奋。脑磁图检查后进行MR扫描,层厚1.5mm。... 目的:应用脑磁图(MEG)研究健康受试者初级体感皮质反应M20的潜伏期、波幅及位置的性别差异。方法:对40例受试者给予双侧腕部正中神经电刺激,固定电流脉冲0.3ms,刺激间期0.5s,诱发初级体感皮质兴奋。脑磁图检查后进行MR扫描,层厚1.5mm。大脑初级体感皮质反应由等电流偶极(ECD)评价。将脑磁图所获得的M20反应叠加到MRI上,形成磁源性影像(MSI)。结果:依照给予电刺激后反应潜伏期不同分别称为M20、M35及M60,因M35及M60易受刺激间期(ISI)的影响,只对M20的潜伏期、波幅及反应位置的性别差异进行分析。结果为(1)M20左、右半球潜伏期男性20.6±1.0ms和20.7±1.2ms,女性20.1±0.9ms和20.2±0.9ms,男女性同侧半球潜伏期无显著性差异(P>0.05);(2)M20左、右半球波幅男性23.6±11.2nAm和25.4±11.2nAm,女性25.8±10.5nAm和27.6±7.8nAm,男女性同侧半球波幅无显著性差异(P>0.05);(3)左半球男女性M20偶极位置在X轴位存在显著性差异(P<0.05),显示男性X轴上与女性相比稍偏外侧,右半球男女性M20偶极位置在X轴位无显著性差异(P>0.05),Y,Z轴无显著性差异(P>0.05);(4)磁源性影像显示所有受试者M20反应峰值均位于中央后回。结论:脑磁图可明确不同性别的大脑初级体感皮质反应M20潜伏期、波幅及位置。磁源性影像显示M20峰值位于? 展开更多
关键词 MR M35 MRI
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磁性阿克拉霉素纳米粒的研制和理化性质
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作者 张伟 沈锡中 +1 位作者 邓勇辉 王吉耀 《复旦学报(医学版)》 CAS CSCD 北大核心 2005年第2期155-159,共5页
目的 制备纳米级磁性阿克拉霉素微粒 ,考察其理化性质和磁场响应性。方法 运用化学沉淀法制备Fe3 O4纳米颗粒 ,并与阿克拉霉素水溶液分散在正己烷油相体系。采用反相微乳液界面聚合的方法生成聚合物将水液滴包埋 ,由此制备内含磁性颗... 目的 制备纳米级磁性阿克拉霉素微粒 ,考察其理化性质和磁场响应性。方法 运用化学沉淀法制备Fe3 O4纳米颗粒 ,并与阿克拉霉素水溶液分散在正己烷油相体系。采用反相微乳液界面聚合的方法生成聚合物将水液滴包埋 ,由此制备内含磁性颗粒和阿克拉霉素的磁性纳米载药系统 ,并通过扫描电镜、透射电镜、动态光散射磁强计等考察磁性阿克拉霉素纳米粒的理化性质及体内外磁场响应性。结果 磁性阿克拉霉素纳米粒平均粒径2 1 0nm ,阿克拉霉素载药率 1 0 .0 %,包封率 36 .2 %。制备过程中的各参数包括单体用量、体系油水相体积比例、有机溶剂的种类和乳化剂的用量等都会影响磁性阿克拉霉素纳米粒粒径和阿克拉霉素包封率。制备后 4℃保存 ,3个月稳定性好。结论 磁性阿克拉霉素纳米粒粒径小 ,载药率和包封率高 ,体外具有良好的磁场响应性。 展开更多
关键词 Fe3O4 4
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Modelling rapid non-destructive test using light weight deflectometer on granular soils across different degrees of saturation
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作者 Javad Ghorbani Arooran Sounthararajah +1 位作者 Troyee Tanu Dutta Jayantha Kodikara 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2732-2748,共17页
This study introduces an advanced finite element model for the light weight deflectometer(LWD),which integrates contact mechanics with fully coupled models.By simulating LWD tests on granular soils at various saturati... This study introduces an advanced finite element model for the light weight deflectometer(LWD),which integrates contact mechanics with fully coupled models.By simulating LWD tests on granular soils at various saturation levels,the model accurately reflects the dependence of the LWD modulus on dry density,water content,and effective stress.This model addresses and overcomes the limitations of previous finite element models for this specific problem.Simultaneously,this research presents the first experimentally validated fully coupled contact impact model.Furthermore,the research provides a comparative assessment of elastoplastic and nonlinear elastic models and contrasts an enriched node-tosegment method(developed in this study)with the more precise mortar technique for contact mechanics.These comparisons reveal unique advantages and challenges for each method.Moreover,the study underscores the importance of careful application of the LWD modulus,emphasising the need for sophisticated tools to interpret soil behaviour accurately. 展开更多
关键词 Granular soils PLASTICITY Finite element analysis Contact mechanics MODULUS Degree of saturation
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鞍区肿瘤的MRI表现与鉴别诊断 被引量:4
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作者 侯金文 李传福 《医学影像学杂志》 1998年第4期200-203,共4页
目的:明确不同类型鞍区肿瘤的MRI特征。材料与方法:回顾性分析44例经手术病理证实的鞍区肿瘤MRI表现。结果:19例垂体大腺瘤、12例颅咽管瘤、9例鞍区脑膜瘤及4例鞍上池表皮样囊肿均有其一定的特征性MRI表现。垂体大腺瘤起源于垂体,... 目的:明确不同类型鞍区肿瘤的MRI特征。材料与方法:回顾性分析44例经手术病理证实的鞍区肿瘤MRI表现。结果:19例垂体大腺瘤、12例颅咽管瘤、9例鞍区脑膜瘤及4例鞍上池表皮样囊肿均有其一定的特征性MRI表现。垂体大腺瘤起源于垂体,大多数向上生长呈“雪人”形,个别向下生长突破鞍底,瘤体内可发生囊变(47%)或出血(32%)而致信号强度不均;颅咽管瘤多发生于鞍上,少数累及鞍内,囊实性或囊性者居多,其中于T1加权像上囊液可呈低、等、高不同信号强度为其特点;脑膜瘤多位于鞍上池前部,信号均匀与脑灰质相似,增强扫描有时可见脑膜尾征;发生于鞍上池的表皮样囊肿沿脑池生长,边缘不规则,信号强度与脑脊液相似。结论:MRI对鞍区肿瘤有重要的鉴别诊断价值。 展开更多
关键词 MRI MRI T1
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Oils with different degree of saturation:effects on ileal digestibility of fat and corresponding additivity and bacterial community in growing pigs
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作者 Lu Wang Yifan Chen +2 位作者 Yuansen Yang Nuo Xiao Changhua Lai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1657-1668,共12页
Background Oils are important sources of energy in pig diets.The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of o... Background Oils are important sources of energy in pig diets.The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of oil supplemented.An experiment was conducted to evaluate the effects of oils with different degree of saturation on the fat digestibility and corresponding additivity and bacterial community in growing pigs.Methods Eighteen crossbred(Duroc×Landrace×Yorkshire)barrows(initial body weight:29.3±2.8 kg)were surgically fitted with a T-cannula in the distal ileum.The experimental diets included a fat-free basal diet and 5 oil-added diets.The 5 oil-added diets were formulated by adding 6%oil with different ratio of unsaturated to saturated fatty acids(U:S)to the basal diet.The 5 oils were palm oil(U:S=1.2),canola oil(U:S=12.0),and palm oil and canola oil were mixed in different proportions to prepare a combination of U:S of 2.5,3.5 and 4.5,respectively.Results The apparent and standardized ileal digestibility(AID and SID)of fat and fatty acids increased linearly(P<0.05)as the U:S of dietary oils increased except for SID of fat and C18:2.The AID and SID of fat and fatty acids differed among the dietary treatments(P<0.05)except for SID of unsaturated fatty acids(UFA)and C18:2.Fitted one-slope broken-line analyses for the SID of fat,saturated fatty acids(SFA)and UFA indicated that the breakpoint for U:S of oil was 4.14(R^(2)=0.89,P<0.01),2.91(R^(2)=0.98,P<0.01)and 3.84(R^(2)=0.85,P<0.01),respectively.The determined SID of fat,C18:1,C18:2 and UFA in the mixtures was not different from the calculated SID of fat,C18:1,C18:2 and UFA.However,the determined SID of C16:0,C18:0 and SFA in the mixtures were greater than the calculated SID values(P<0.05).The abundance of Romboutsia and Turicibacter in pigs fed diet containing palm oil was greater than that in rapeseed oil treatment group,and the two bacteria were negatively correlated with SID of C16:0,C18:0 and SFA(P<0.05).Conclusions The optimal U:S for improving the utilization efficiency of mixed oil was 4.14.The SID of fat and UFA for palm oil and canola oil were additive in growing pigs,whereas the SID of SFA in the mixture of two oils was greater than the sum of the values of pure oils.Differences in fat digestibility caused by oils differing in degree of saturation has a significant impact on bacterial community in the foregut. 展开更多
关键词 ADDITIVITY Bacterial community Fat and fatty acids Growing pigs Ratio of unsaturated to saturated fatty acids Standardized ileal digestibility
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Experimental analysis of matrix moveable oil saturation in tight sandstone reservoirs of the south Ordos Basin,China
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作者 Ting Xu Jun Pu +1 位作者 Xuejie Qin Yi Wei 《Energy Geoscience》 EI 2024年第1期184-195,共12页
Tight oil reservoirs in the south Ordos Basin are characterized by fractured,heterogeneous oil-bearing strata(an oil saturation of less than 55%on average),normal pressure(0.8±)and extra-low permeability(less tha... Tight oil reservoirs in the south Ordos Basin are characterized by fractured,heterogeneous oil-bearing strata(an oil saturation of less than 55%on average),normal pressure(0.8±)and extra-low permeability(less than 0.3 mD).In the Chang 8 tight sandstone reservoir in Honghe oilfield,micro-and nanopores,especially those with a pore-throat radius of less than 1 mm,account for more than 90%.Fluid flow in the matrix is non-linear and crude oil flow rates are very low under normal pressure gradients.An improved understanding of oil mobility in a tight matrix is key to further development of normalpressure tight-oil resources in the continental basin.In this study,constant-velocity and high-pressure mercury injection experiments were conducted using samples of typical tight sandstone cores obtained from the south of Ordos Basin.A new method for reconstructing the full-scale pore-throat distribution characteristics of tight sandstone reservoirs was established successfully,based on which multistage centrifugal tests,tests of low-pressure differential displacement of oil by water,and nuclear magnetic resonance tests were conducted in order to obtain the distribution characteristics of moveable fluid in different pores.The moveable oil saturation(MOS)and degree of oil recovery(i.e.ratio of accumulative oil production to producing geologic reserves)of the core samples under different differential pressures for displacement were determined.As for the tight oil reservoirs in the south Ordos Basin,the moveable fluids are mainly stored in sub-micron(0.10-0.5 mm)pores.For Type I reservoirs(k>0.1 mD),the volume percentage of moveable fluid in pores with a radius larger than 0.5 mm is relatively high(greater than 40%).The degree of oil recovery of water flooding serves as the basis for forecasting recoverable reserves for tight oil reservoirs.Recoverable reserves under water flooding,mainly occur in pores with a radius greater than 0.5 mm.The contribution of Type I reserves to oil production is observed to be greater than 60%,and the degree of oil recovery reaches up to 17.1%.These results help improve our understanding on the evaluation and classification of Chang 8 tight sandstone reservoirs in Honghe oilfield and serve as theoretical basis for pilot tests to explore effective injection media and development methods to improve the matrix-driven pressure differences and displacement efficiency for oil. 展开更多
关键词 Tight reservoir Pore-throat structure Moveable fluid volume Moveable oil saturation(MOS) Waterflooding oil recovery South Ordos basin
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鞍区胶质瘤的CT和MRI诊断 被引量:11
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作者 彭旭红 张雪林 +1 位作者 许尚文 杨波 《临床放射学杂志》 CSCD 北大核心 2005年第6期481-483,共3页
目的分析鞍区胶质瘤的CT和MRI特点及临床发病特征。资料与方法经手术病理证实的鞍区胶质瘤8例,其中7例位于鞍上,1例位于鞍内。3例行CT检查,5例行MRI检查。结果鞍上胶质瘤体积较大,呈不规则分叶状,边界光滑锐利,基本没有瘤周水肿,瘤内偏... 目的分析鞍区胶质瘤的CT和MRI特点及临床发病特征。资料与方法经手术病理证实的鞍区胶质瘤8例,其中7例位于鞍上,1例位于鞍内。3例行CT检查,5例行MRI检查。结果鞍上胶质瘤体积较大,呈不规则分叶状,边界光滑锐利,基本没有瘤周水肿,瘤内偏上方多发囊变,无明显钙化及出血,少数可沿视觉通路生长,CT平扫稍低或等密度,MRI检查T1WI呈稍低、低信号,T2WI高信号,CT及MR增强扫描,肿瘤实性部分可见显著强化。此外,临床上这些患者就诊时多有眼部症状,而均无下丘脑及垂体内分泌异常症状。鞍内胶质瘤位置偏后,瘤周无水肿,瘤内可有多发微囊变,无明显钙化及出血。结论鞍上胶质瘤有比较典型的CT和MRI特点,结合患者临床发病特点,有助于提高其术前诊断率;鞍内胶质瘤易误诊,对有多发微囊变的位置偏后的鞍内肿瘤,应考虑到本病可能。 展开更多
关键词 MRI MRI MRI MR CT CT T1WI T2WI
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