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Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses
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作者 Ting-Zhi Yan Shan Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期228-236,共9页
The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(ever... The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains. 展开更多
关键词 Exotic nuclei unified neutron skin thickness Yield ratios IQMD
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Unified deep learning model for predicting fundus fluorescein angiography image from fundus structure image
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作者 Yiwei Chen Yi He +3 位作者 Hong Ye Lina Xing Xin Zhang Guohua Shi 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第3期105-113,共9页
The prediction of fundus fluorescein angiography(FFA)images from fundus structural images is a cutting-edge research topic in ophthalmological image processing.Prediction comprises estimating FFA from fundus camera im... The prediction of fundus fluorescein angiography(FFA)images from fundus structural images is a cutting-edge research topic in ophthalmological image processing.Prediction comprises estimating FFA from fundus camera imaging,single-phase FFA from scanning laser ophthalmoscopy(SLO),and three-phase FFA also from SLO.Although many deep learning models are available,a single model can only perform one or two of these prediction tasks.To accomplish three prediction tasks using a unified method,we propose a unified deep learning model for predicting FFA images from fundus structure images using a supervised generative adversarial network.The three prediction tasks are processed as follows:data preparation,network training under FFA supervision,and FFA image prediction from fundus structure images on a test set.By comparing the FFA images predicted by our model,pix2pix,and CycleGAN,we demonstrate the remarkable progress achieved by our proposal.The high performance of our model is validated in terms of the peak signal-to-noise ratio,structural similarity index,and mean squared error. 展开更多
关键词 Fundus fluorescein angiography image fundus structure image image translation unified deep learning model generative adversarial networks
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Unified Control Theory from PID to ACPID
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作者 Zhezhao Zeng Yuqi Tang 《Advances in Pure Mathematics》 2024年第7期523-545,共23页
To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been propose... To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering. 展开更多
关键词 Insert Nonlinear Systems PID Control ACPID Control Total Disturbance unified Control Theory Zeng’s Stabilization Rules (ZSR)
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CHINA’S PUSH FOR UNIFIED NATIONAL MARKET BRINGS NEW OPPORTUNITIES
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作者 Tom Fowdy 《China Report ASEAN》 2024年第2期79-79,共1页
In recent years,China has implemented measures to advance the building of a unified national market,aiming to boost domestic demand and consolidate the foundations of its economic recovery.In March 2022,the Chinese go... In recent years,China has implemented measures to advance the building of a unified national market,aiming to boost domestic demand and consolidate the foundations of its economic recovery.In March 2022,the Chinese government issued a guideline on accelerating the construction of a unified national market.The issue was also a focus at the annual Central Economic Work Conference held in December 2023. 展开更多
关键词 unified PUSH measures
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The Unified Field
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第7期1010-1035,共26页
This is a Unified Field description based on the holographic Time Dilation Cosmology, TDC, model, which is an eternal continuum evolving forward in the forward direction of time, at the speed of light, c, at an invari... This is a Unified Field description based on the holographic Time Dilation Cosmology, TDC, model, which is an eternal continuum evolving forward in the forward direction of time, at the speed of light, c, at an invariant 1 s/s rate of time. This is the Fundamental Direction of Evolution, FDE. There is also an evolution down time dilation gradients, the Gravitational Direction of Evolution, GDE. These evolutions are gravity, which is the evolutionary force in time. Gravitational velocities are compensation for the difference in the rate of time, dRt, in a dilation field, and the dRtis equal to the compensatory velocity’s percentage of c, and is a measure of the force in time inducing the velocity. In applied force induced velocities, the dRt is a measure of the resistance in time to the induced velocity, which might be called “anti-gravity” or “negative gravity”. The two effects keep the continuum uniformly evolving forward at c. It is demonstrated that gravity is already a part of the electromagnetic field equations in way of the dRt element contained in the TDC velocity formula. Einstein’s energy formula is defined as a velocity formula and a modified version is used for charged elementary particle solutions. A time dilation-based derivation of the Lorentz force ties gravity directly to the electromagnetic field proving the unified field of gravity and the EMF. It is noted how we could possibly create gravity drives. This is followed by a discussion of black holes, proving supermassive objects, like massive black hole singularities, are impossible, and that black holes are massless Magnetospheric Eternally Collapsing Objects (MECOs) that are vortices in spacetime. . 展开更多
关键词 unified Field GRAVITY Anti-Gravity Astrophysics Einstein General Relativity Special Relativity Galactic Rotation Velocities Time Dilation SPACETIME Space Time Spacetime Continuum Quantum Continuum MECO Black Hole Event Horizon Timelike Spacelike Lightlike
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Fundamental Issues Towards Unified Design Theory of Recycled and Natural Aggregate Concrete Components 被引量:1
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作者 Jianzhuang Xiao Kaijian Zhang +2 位作者 Tao Ding Qingtian Zhang Xuwen Xiao 《Engineering》 SCIE EI CAS CSCD 2023年第10期188-197,共10页
In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of research.However,the design methodology for RAC structural components remains a challenge.Conseque... In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of research.However,the design methodology for RAC structural components remains a challenge.Consequently,demands for a unified design of natural aggregate concrete(NAC)and RAC components have been presented.Accordingly,this study analyses the necessity of a unified design theory and provides an in-depth demonstration of the strength determination,compressive constitutive relationship,and design method of concrete components.The coefficient of variation of RAC strength is found to be generally higher than that of NAC strength.The compressive and tensile strengths of RAC can be defined and determined using the same method as that used for NAC.The uniaxial compressive constitutive relationship between NAC and RAC has a unified mathematical expression.However,the elastic modulus of RAC decreases,and its brittleness exhibits an increasing trend compared with that of NAC.Finally,to unify the design formulae of RAC and NAC components for bearing capacity,modification factors for RAC components are proposed considering safety and reliability.Additionally,the feasibility of the proposed unified time-dependent design theory is demonstrated in terms of conceptual design and structural measures considering the effects of strength degradation and reinforcement corrosion.It is believed that this study enriches and develops the basic theory of concrete structures. 展开更多
关键词 Recycled aggregate concrete(RAC) Natural aggregate concrete(NAC) Strength determination Constitutive relation Reliability unified design theory
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Analysis and Power Quality Improvement in Hybrid Distributed Generation System with Utilization of Unified Power Quality Conditioner
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作者 Noor Zanib Munira Batool +4 位作者 Saleem Riaz Farkhanda Afzal Sufian Munawar Ibtisam Daqqa Najma Saleem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1105-1136,共32页
This paper presents a comprehensive study that includes the sizing and power flow by series and parallel inverters in a distributed generation system(DGs)that integrates the system of hybrid wind photovoltaic with a u... This paper presents a comprehensive study that includes the sizing and power flow by series and parallel inverters in a distributed generation system(DGs)that integrates the system of hybrid wind photovoltaic with a unified power quality conditioner(UPQC).In addition to supplying active power to the utility grid,the system of hybrid wind photovoltaic functions as a UPQC,compensating reactive power and suppressing the harmonic load currents.Additionally,the load is supplied with harmonic-free,balanced and regulated output voltages.Since PVWind-UPQC is established on a dual compensation scheme,the series inverter works like a sinusoidal current source,while the parallel inverter works like a sinusoidal voltage source.Consequently,a smooth alteration from interconnected operating modes to island operating modes and vice versa can be achieved without load voltage transients.Since PV-Wind-UPQC inverters handle the energy generated through the hybrid wind photovoltaic system and the energy demanded through the load,the converters should be sized cautiously.A detailed study of the flow of power via the PV-Wind-UPQC is imperative to gain a complete understanding of the system operation and the proper design of the converters.Thus,curves that allow the sizing of the power converters according to the power flow via the converters are presented and discussed.Simulation results are presented to assess both steady state and dynamic performances of the grid connected hybrid system of PV-Wind-UPQC.This investigation is verified by simulating and analyzing the results with Matlab/Simulink. 展开更多
关键词 PHOTOVOLTAIC wind turbine unified power quality conditioner power flow distributed generation system
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Fractional derivative statistical damage model of unsaturated expansive soil based on unified hydraulic effect
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作者 ZHANG Hua WANG Peng 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2769-2782,共14页
Unsaturated expansive soil is widely distributed in China and has complex engineering properties.This paper proposes the unified hydraulic effect shear strength theory of unsaturated expansive soil based on the effect... Unsaturated expansive soil is widely distributed in China and has complex engineering properties.This paper proposes the unified hydraulic effect shear strength theory of unsaturated expansive soil based on the effective stress principle,swelling force principle,and soil–water characteristics.Considering the viscoelasticity and structural damage of unsaturated expansive soil during loading,a fractional hardening–damage model of unsaturated expansive soil was established.The model parameters were established on the basis of the proposed calculation method of shear strength and the triaxial shear experiment on unsaturated expansive soil.The proposed model was verified by the experimental data and a traditional damage model.The proposed model can satisfactorily describe the entire process of the strain-hardening law of unsaturated expansive soil.Finally,by investigating the damage variables of the proposed model,it was found that:(a)when the values of confining pressure and matric suction are close,the coupling of confining pressure and matric suction contributes more to the shear strength;(b)there is a damage threshold for unsaturated expansive soil,and is mainly reflected by strength criterion of infinitesimal body;(c)the strain hardening law of unsaturated expansive soil is mainly reflected by fractional derivative operator. 展开更多
关键词 Unsaturated expansive soil unified hydraulic effect Shear strength theory Hardening-damage model Fractional derivative
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Unified Understanding of Cosmological Energy Fields: Exploring Gravitation, Repulsion, and More
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作者 Pramod Kumar Agrawal 《Natural Science》 2023年第11期263-284,共22页
First, we develop a unitary process that can explain all four physical activations: electromagnetic wave, electromagnetic force, repulsion, and attraction. Second, it is clarified that cosmological and physical entiti... First, we develop a unitary process that can explain all four physical activations: electromagnetic wave, electromagnetic force, repulsion, and attraction. Second, it is clarified that cosmological and physical entities relate to different levels of existence in the universe and, hence, cannot be considered under the same paradigm. We know that biological entities use physical substances as executants;analogously, physical entities use cosmological substances as executants. Therefore, we have introduced new terms for the cosmological substances used as executants in physical activities. Third, this study introduces the primary elements of the cosmological world, such as visibility, forcibility, fullness, and hollowness, and defines them according to their attributes. This study explains how different combinations and placements of primary elements create different cosmological fields. These fields are used in all physical activations. Finally, we explain the entity model and how all physical activations occur. This study concludes that all physical activations use primary elements and follow the same universal law. Therefore, this study addresses the untouched subject of the creation of repulsion and attraction (gravitation). Furthermore, it addresses several cosmic mysteries that are yet to be resolved. 展开更多
关键词 Cause of Gravitation Cause of Repulsion Model of Entity unified Theory Multi-Disciplinary Approach
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Monoidal Hom-unified积与monoidal Hom-Hopf代数的可裂扩张
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作者 李敏 张腾月 陈全国 《曲阜师范大学学报(自然科学版)》 CAS 2023年第3期21-24,共4页
从monoidal Hom-Hopf代数的分裂扩张的观点出发,对monoidal Hom-unified积进行等价刻画,即一个monoidal Hom-Hopf代数(E,β)同构于一个monoidal Hom-unified积(A■H,α■γ)当且仅当存在一个可裂单的monoidal Hom-Hopf代数同态i:(A,α)... 从monoidal Hom-Hopf代数的分裂扩张的观点出发,对monoidal Hom-unified积进行等价刻画,即一个monoidal Hom-Hopf代数(E,β)同构于一个monoidal Hom-unified积(A■H,α■γ)当且仅当存在一个可裂单的monoidal Hom-Hopf代数同态i:(A,α)→(E,β). 展开更多
关键词 monoidal Hom-Hopf代数 monoidal Hom-unified 可裂单态射
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An Outline of the Grand Unified Theory of Gauge Fields
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作者 Bi Qiao 《Journal of Modern Physics》 CAS 2023年第3期212-326,共25页
This paper attempts to propose a grand unified guiding principle of gauge fields from the mathematical and physical picture of fiber bundles: it is believed that our universe may have more fundamental interactions tha... This paper attempts to propose a grand unified guiding principle of gauge fields from the mathematical and physical picture of fiber bundles: it is believed that our universe may have more fundamental interactions than the four fundamental interactions, and the gauge fields of these fundamental interactions are just a unified gauge potential on the fiber bundle manifold or the components connected to the bottom manifold, that is, our universe;these components can meet the transformation of gauge potential, and even can be transformed from a fundamental interaction gauge potential to another fundamental interaction gauge potential, and can be summarized into a unified equation, namely the expression of the generalized gauge equation, corresponding to the gauge transformation invariance;so gauge transformation invariance is a necessary condition to unify field theory, but quantization of field is not a necessary condition;the four (or more) fundamental interaction fields of the universe are unified into a universal gauge field defined by the connection of the principal fiber bundle on the cosmic base manifold. 展开更多
关键词 Gauge Field Principal Fiber Bundle Gauge Transformation Invariance Grand unified Theory of Physics
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Scavenging Microwave Wireless Power:A Unified Model,Rectenna Design Automation,and Cutting-Edge Techniques
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作者 Si-Ping Gao Jun-Hui Ou +1 位作者 Xiuyin Zhang Yongxin Guo 《Engineering》 SCIE EI CAS CSCD 2023年第11期32-48,共17页
While sufficient review articles exist on inductive short-range wireless power transfer(WPT),long-haul microwave WPT(MWPT)for solar power satellites,and ambient microwave wireless energy harvesting(MWEH)in urban areas... While sufficient review articles exist on inductive short-range wireless power transfer(WPT),long-haul microwave WPT(MWPT)for solar power satellites,and ambient microwave wireless energy harvesting(MWEH)in urban areas,few studies focus on the fundamental modeling and related design automation of receiver systems.This article reviews the development of MWPT and MWEH receivers,with a focus on rectenna design automation.A novel rectifier model capable of accurately modeling the rectification process under both high and low input power is presented.The model reveals the theoretical boundary of radio frequency-to-direct current(dc)power conversion efficiency and,most importantly,enables an automated system design.The automated rectenna design flow is sequential,with the minimal engagement of iterative optimization.It covers the design automation of every module(i.e.,rectifiers,matching circuits,antennae,and dc–dc converters).Scaling-up of the technique to large rectenna arrays is also possible,where the challenges in array partitioning and power combining are briefly discussed.In addition,several cutting-edge rectenna techniques for MWPT and MWEH are reviewed,including the dynamic range extension technique,the harmonics-based retro-directive technique,and the simultaneous wireless information and power transfer technique,which can be good complements to the presented automated design methodology. 展开更多
关键词 Microwave wireless power transfer Microwave wireless energy harvesting unified Rectifier model Automated rectenna design Emerging rectenna techniques
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Research and Practice on High Availability Scheme of Unified Identity Authentication System Based on CAS in Colleges and Universities
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作者 Man Liu Lei Yu 《Journal of Information Security》 2023年第1期16-24,共9页
Unified identity authentication has become the basic information service provided by colleges and universities for teachers and students. Security, stability, high concurrency and easy maintenance are our requirements... Unified identity authentication has become the basic information service provided by colleges and universities for teachers and students. Security, stability, high concurrency and easy maintenance are our requirements for a unified identity authentication system. Based on the practical work experience of China University of Geosciences (Beijing), this paper proposes a high availability scheme of unified identity authentication system based on CAS, which is composed of multiple CAS Servers, Nginx for load balancing, and Redis as a cache database. The scheme has been practiced in China University of Geosciences (Beijing), and the application effect is good, which has practical reference significance for other universities. 展开更多
关键词 unified Identity Authentication CAS REDIS High Availability Colleges and Universities
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Reachable set estimation for discrete-time Markovian jump neural networks with unified uncertain transition probability
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作者 Yufeng Tian Wengang Ao Peng Shi 《Journal of Automation and Intelligence》 2023年第3期167-174,共8页
This paper focuses on the reachable set estimation for Markovian jump neural networks with time delay.By allowing uncertainty in the transition probabilities,a framework unifies and enhances the generality and realism... This paper focuses on the reachable set estimation for Markovian jump neural networks with time delay.By allowing uncertainty in the transition probabilities,a framework unifies and enhances the generality and realism of these systems.To fully exploit the unified uncertain transition probabilities,an equivalent transformation technique is introduced as an alternative to traditional estimation methods,effectively utilizing the information of transition probabilities.Furthermore,a vector Wirtinger-based summation inequality is proposed,which captures more system information compared to existing ones.Building upon these components,a novel condition that guarantees a reachable set estimation is presented for Markovian jump neural networks with unified uncertain transition probabilities.A numerical example is illustrated to demonstrate the superiority of the approaches. 展开更多
关键词 Markovian jump neural networks unified uncertain transition probabilities Reachable set estimation Double-boundary approach Vector wirtinger-based summation inequality
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基于OPC Unified Architecture的服务器研究 被引量:8
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作者 孙发 刘枫 《仪器仪表标准化与计量》 2006年第5期14-17,共4页
首先介绍现有OPC规范以及其存在的不足,然后介绍OPC基金会即将推出的OPCUnifiedArchitecture规范,并重点研究OPCUnifiedArchitecture服务器的实现机制及方法,通过与现有OPC规范的比较,揭示OPCUA在平台无关性、可互操作性、可靠性等方面... 首先介绍现有OPC规范以及其存在的不足,然后介绍OPC基金会即将推出的OPCUnifiedArchitecture规范,并重点研究OPCUnifiedArchitecture服务器的实现机制及方法,通过与现有OPC规范的比较,揭示OPCUA在平台无关性、可互操作性、可靠性等方面的显著优势。 展开更多
关键词 OPC OPC unified ARCHITECTURE 可互操作
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UPLC-Q-TOF-MS^(E)技术结合UNIFI筛查平台分析加味逍遥丸化学成分 被引量:4
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作者 孙健 刘子维 +9 位作者 刘莹 张美玉 李孟莹 张海鸣 聂颖兰 权建野 闫寒 彭娟 栗俞程 杨书彬 《中国药物警戒》 2023年第2期181-190,共10页
目的运用高效液相色谱-四极杆-飞行时间串联质谱法(UPLC-Q-TOF-MS^(E))对加味逍遥丸的化学成分进行分析与鉴定,为复方质量控制及药效物质基础研究提供理论依据。方法采用ACQUITY UPLC BEH C_(18)柱(2.1 mm×100 mm,1.7μm,Waters),... 目的运用高效液相色谱-四极杆-飞行时间串联质谱法(UPLC-Q-TOF-MS^(E))对加味逍遥丸的化学成分进行分析与鉴定,为复方质量控制及药效物质基础研究提供理论依据。方法采用ACQUITY UPLC BEH C_(18)柱(2.1 mm×100 mm,1.7μm,Waters),以0.1%甲酸水-乙腈为流动相,梯度洗脱,进样量5μL,流速0.3 mL·min^(-1),柱温40℃。采用电喷雾离子源,在正、负2种模式下进行复方质谱检测与分析,并且使用UNIFI平台对MS^(E)模式下采集的质谱数据,结合化合物准分子离子、质谱裂解途径及标准品进行结构确认。结果通过分析目标化合物的分子离子峰和二级质谱特征碎片离子,并且结合标准品裂解规律以及相关文献资料,共鉴定了其中78个化学成分,包括3个倍半萜类成分、4个苯丙素类成分、13个单萜类成分、7个酚类成分、5个环烯醚萜类成分、10个黄酮类成分、23个三萜类成分及13个其他类成分。结论运用UPLC-Q-TOF-MS^(E)技术可快速分析鉴定复方加味逍遥丸的主要化合物类型,可为复方质量控制及药效物质基础研究提供理论依据。 展开更多
关键词 加味逍遥丸 高效液相色谱-四级杆-飞行时间串联质谱法(UPLC-Q-TOF-MS^(E)) 化学成分 unifi平台
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Unified symmetry of nonholonomic mechanical systems with variable mass 被引量:7
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作者 夏丽莉 李元成 +1 位作者 后其宝 王静 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期903-906,共4页
Based on the total time derivative along the trajectory of the system the definition and the criterion for a unified symmetry of nonholonomic mechanical system with variable mass are presented in this paper. A new con... Based on the total time derivative along the trajectory of the system the definition and the criterion for a unified symmetry of nonholonomic mechanical system with variable mass are presented in this paper. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced from the unified symmetry, are also obtained, An example is given to illustrate the application of the results. 展开更多
关键词 variable mass nonholonomic mechanical system unified symmetry conserved quantity
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Unified analytical solution for deep circular tunnel with consideration of seepage pressure,grouting and lining 被引量:5
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作者 李学峰 杜守继 陈兵 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1483-1493,共11页
A new unified analytical solution is presented for predicting the range of plastic zone and stress distributions around a deep circular tunnel in a homogeneous isotropic continuous medium. The rock mass, grouting zone... A new unified analytical solution is presented for predicting the range of plastic zone and stress distributions around a deep circular tunnel in a homogeneous isotropic continuous medium. The rock mass, grouting zone and lining are assumed as elastic-perfectly plastic and governed by the unified strength theory(UST). This new solution has made it possible to consider the interaction between seepage pressure, lining, grouting and rock mass, and the intermediate principal stress effect together. Moreover, parametric analysis is carried out to identify the influence of the related parameters on the plastic zone radius. Under the given conditions, the results show that the plastic zone radius decreases with an increasing cohesion, internal friction angle and hydraulic conductivity of lining and unified failure criterion parameter, respectively; whereas the plastic zone radius increases with the growth of elasticity modulus of lining. Comparison of results from the new solution and the other published one shows well agreement and provides confidence in the new solution proposed. 展开更多
关键词 unified strength theory (UST) INTERMEDIATE principal stress SEEPAGE pressure GROUTING LINING analytical solution
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A unified gas-kinetic scheme for multiscale and multicomponent flow transport 被引量:3
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作者 Tianbai XIAO Kun XU Qingdong CAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第3期355-372,共18页
Compressible flows exhibit a diverse set of behaviors, where individual particle transports and their collective dynamics play different roles at different scales. At the same time, the atmosphere is composed of diffe... Compressible flows exhibit a diverse set of behaviors, where individual particle transports and their collective dynamics play different roles at different scales. At the same time, the atmosphere is composed of different components that require additional degrees of freedom for representation in computational fluid dynamics. It is challenging to construct an accurate and efficient numerical algorithm to faithfully represent multiscale flow physics across different regimes. In this paper, a unified gas-kinetic scheme(UGKS) is developed to study non-equilibrium multicomponent gaseous flows. Based on the Boltzmann kinetic equation, an analytical space-time evolving solution is used to construct the discretized equations of gas dynamics directly according to cell size and scales of time steps, i.e., the so-called direct modeling method. With the variation in the ratio of the numerical time step to the local particle collision time(or the cell size to the local particle mean free path), the UGKS automatically recovers all scale-dependent flows over the given domain and provides a continuous spectrum of the gas dynamics. The performance of the proposed unified scheme is fully validated through numerical experiments.The UGKS can be a valuable tool to study multiscale and multicomponent flow physics. 展开更多
关键词 unified gas-kinetic scheme(UGKS) multiscale modeling MULTICOMPONENT flow
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Unified Water Gravity Wave Theory and Improved Linear Wave 被引量:3
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作者 Fu Yuhua Senior Engineer, Structural Engineering Department, China Offshore Oil Development and Engineering Corp., Beijing 《China Ocean Engineering》 SCIE EI 1992年第1期57-64,共8页
Based on Least Square Method, this paper presents variational principle for handling various water gravity wave theories and the unified water gravity wave theory was given. By using this variational principle of unif... Based on Least Square Method, this paper presents variational principle for handling various water gravity wave theories and the unified water gravity wave theory was given. By using this variational principle of unified water wave theory, two kinds of improved linear waves were derived. The first one uses the same boundary conditions which were applied to derive 5-order Stokes wave. The second one uses the accurate boundary conditions (Eqs. 11 and 12). The two improved linear waves were compared with the existing linear wave. 展开更多
关键词 WAVE unified theory improved linear wave
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