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光纤端面涂覆敏感材料的高灵敏度传感器

光电子．激光 2022年第4期33卷 349-355页

作者：陈海林江超叶文豪王媛宋娇李宏湖北师范大学物理与电子科学学院湖北黄石435002

描述了一种基于法布里-佩罗干涉仪(Fabry-Perot interferometer, FPI)结构的双参数光纤传感器,并演示了它可以同时测量气压和温度。所提出的FPI传感结构由覆盖在单模光纤端面上半球形的紫外固化胶组成,FPI产生的光谱干涉峰对环境温度和... 详细信息

描述了一种基于法布里-佩罗干涉仪(Fabry-Perot interferometer, FPI)结构的双参数光纤传感器,并演示了它可以同时测量气压和温度。所提出的FPI传感结构由覆盖在单模光纤端面上半球形的紫外固化胶组成,FPI产生的光谱干涉峰对环境温度和气压变化敏感。选择传感器干涉谱中两个谐振峰波谷Dip 1和Dip 2,跟踪它们的波长随气压和温度的变化,构建传输矩阵,能够同时测量气压和温度,并消除交叉敏感。实验结果表明Dip 1点的气压与温度灵敏度分别为2.925 nm/MPa和-1.165 nm/℃,Dip 2点的气压与温度灵敏度分别为4.715 nm/MPa和-1.209 nm/℃。利用Dip 1和Dip2的气压与温度灵敏度构建测量矩阵,传感器实现了多参数测量。通过长时间稳定性实验发现传感器测量气压与温度的最大误差分别为0.068 MPa和0.19℃。该传感器具有灵敏度高、结构简单紧凑、造价低廉等优点,在工业生产中具有一定的应用价值。

关键词：光纤传感器法布里-珀罗干涉仪紫外(ultraviolet UV)胶气压温度

Quadric SFDI for Laplacian Discretisation in Lagrangian Meshless Methods

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Journal of Marine Science and Application 2020年第3期19卷 362-380页

作者： Shiqiang Yan Q.w.Ma Jinghua w.ng School of Mathematics Computer Science and EngineeringUniversity of LondonEC1V 0HBLondonUK

In the Lagrangian meshless(particle)methods,such as the smoothed particle hydrodynamics(SPH),moving particle semi-implicit(MPS)method and meshless local Petrov-Galerkin method based on Rankine source solution(MLPG_R),the Laplacian discretisation is often required in order to solve the governing equations and/or estimate physical quantities(such as the viscous stresses).In some meshless applications,the Laplacians are also needed as stabilisation operators to enhance the pressure *** particles in the Lagrangian methods move follow.ng the material velocity,yielding a disordered(random)particle distribution even though they may be distributed uniformly in the initial *** schemes have been developed for a direct estimation of second derivatives using finite difference,kernel integrations and weighted/moving least square *** of the schemes suffer from a poor convergent *** have a better convergent rate but require inversions of high order matrices,yielding high computational *** paper presents a quadric semi-analytical finite-difference interpolation(QSFDI)scheme,which can achieve the same degree of the convergent rate as the best schemes available to date but requires the inversion of significant lower-order matrices,i.e.3×3 for 3D cases,compared with 6×6 or 10×10 in the schemes with the best convergent *** patch tests have been carried out for either estimating the Laplacian of given functions or solving Poisson’s *** convergence,accuracy and robustness of the present schemes are compared with the existing *** will show that the present scheme requires considerably less computational time to achieve the same accuracy as the best schemes available in literatures,particularly for estimating the Laplacian of given functions.

关键词： Laplacian discretisation Lagrangian meshless methods QSFDI Random/disordered particle distribution Poisson’s equation Patch tests

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土壤中营养及污染元素的化学平衡第1版

土壤中营养及污染元素的化学平衡

石墨烯带长度变化与电子结构和电子输运的关系

1986年

作者：（美）w·L·Lindsay

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固体电子学研究与进展 2012年第1期32卷 1-5,35页

作者：陈蕾闫雨桐 Terence K S w 王利光江南大学理学院江苏无锡214122 新加坡南洋理工大学电气与电子工程学院新加坡636798

利用基于非平衡格林函数的密度泛函方法,对长度变化石墨烯带的电子结构和输运特性进行了研究,得出在同一长度的石墨烯带内,系统态密度的峰值与电子传输概率的峰值具有较好的对应关系,但是电子传输概率的大小与电子态密度值的大小没有明... 详细信息

利用基于非平衡格林函数的密度泛函方法,对长度变化石墨烯带的电子结构和输运特性进行了研究,得出在同一长度的石墨烯带内,系统态密度的峰值与电子传输概率的峰值具有较好的对应关系,但是电子传输概率的大小与电子态密度值的大小没有明显的正比关系。随着长度的增加,电子的传输更倾向于集中在某几个能量态,传输曲线呈现梳齿状,这是由于石墨烯带越长,电子态呈现越稳定的分布。研究还得出不同长度的石墨烯带的电导值和HOM O-LUM O差值成反比,且随着石墨烯带长度增大,其电导出现非线性变化,且呈现规则的振荡状态。

关键词：石墨烯带密度泛函电子传输态密度

Critical Void Volume Fraction Identification Based on Mesoscopic Damage Model for NVA Shipbuilding Steel

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Journal of Marine Science and Application 2019年第4期18卷 444-456页

作者： Zijie Song Zhiqiang Hu Jonas w.Ringsberg State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Engineering Newcastle UniversityNewcastle upon Tyne NE17RUUK Department of Mechanics and Maritime Sciences Chalmers University of TechnologySE-41296 GothenburgSweden

NVA mild steel is a commonly used material in the shipbuilding *** accurate model for description of this material’s ductile fracture behaviour in numerical simulation is still a challenging *** this paper,a new method for predicting the critical void volume fraction fc in the Guson-Tvergaard-Needleman(GTN)model is introduced to describe the ductile fracture behaviour of NVA shipbuilding mild steel during ship collision and grounding *** of the previous methods for determination of the parameter fc use a converse method,which determines the values of the parameters through comparisons between experi-mental results and numerical simulation results but with high uncertainty.A new method is proposed based on the Hill,Bressan,and williams hypothesis,which reduces the uncertainty to a satisfying *** accurately describe the stress-strain relationship of materials before and after necking,a combination of the Voce and Swift models is used to describe the material properties of NVA mild steel.A user-defined material subroutine has been developed to enable the application of the new parameter deter-mination method and its implementation in the finite element software *** is observed that the model can accurately describe structural damage by comparing the numerical simulation results with those of experiments;thus,the results demon-strate the model’s capacity for structural response prediction in ship collision and grounding scenario simulations。

关键词： Ship collision and grounding Guson-Tvergaard-Needleman model NVA steel Ductile fracture Finite element method

Complexation of Both Enantiomers of 2-Phenylpropionic Acid with Cyclodextrin: Determination of Binding Constant, Stoichiometry, Bioavailability and Co-Conformation

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Journal of Encapsulation and Adsorption Sciences 2012年第3期2卷 48-59页

作者： Ali Aboel Dahab Norman w. Smith Pharmaceutical Sciences Research Division King’s College London UK

Although enantiomers of 2-phenylpropionic acids (2-PPAs), or profens are important group of nonsteroidal anti-inflammatory drugs (NSAIDs) and have been in clinical use for many years, there is no literature covering its binding interaction in particular with cyclodextrins. NSAIDs are marketed as racemates, chiral discrimination and knowledge of enantiomeric bioavailability is essential. Circular dichroism (CD) spectroscopy is the technique of choice for elucidating chirality and monitoring and characterizing molecular recognition phenomena in solution. Methods em-ploying the fundamentals of the simultaneous measurements of absorbance and CD and a novel efficient titration method have been developed to study the binding of β-Cyclodextrin (β-CyD) and the two enantiomers of 2-PPA as a function of pH. The effect on physicochemical properties and bioavailability was investigated. The binding constant, stoichiometry and pKa for both the free and the bound drugs were determined using a Levenburg-Marquadt non-linear equation. The exact nature of the enantiomer discriminating interactions by cyclodextrins (CyDs) is not well understood. In this work, the interactions and co-conformations of both enantiomers of 2-PPA with β-CyD were explained and es-timated using spectroscopic variations upon complexation. The results indicated a change in the physicochemical prop-erties of 2-PPAs upon complexation and highlighted the enantioselective binding of β-CyD as a function of pH. The charge on the guest molecule and its stereochemistry are of great importance in regulating the stability of the guest/β-CyD complexes;hence the bioavailability of drugs. This work elucidates 2-PPAs/β-CyD binding interactions and highlights the effect of β-CyD on drugs with an effective novel method for binding titration and the potential of the simultaneous measurements of absorbance and CD in future chiral drug interactions studies.

关键词： β-Cyclodextrin Binding Constant Bioavailability 2-Phenylpropionic Acid UV and Circular Dichroism

Electrochemical corrosion behavior of bulk ultra-fine grained Fe-Ni-Cr alloy

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Transactions of Nonferrous Metals Society of China 2014年第6期24卷 1989-1994页

作者：武占文陈吉朴楠孙成 w.HASSAN 张星航谢禹钧辽宁石油化工大学机械工程学院抚顺113001 中海油能源发展股份有限公司管道工程分公司天津300452 Department of Mechanical Engineering Materials Science and Engineering ProgramTexas A&M UniversityCollege Station

The corrosion behavior of bulk ultra-fine grained（UFG） Fe-Ni-Cr alloy prepared by equal-channel angular pressing technique was investigated in 0.25 mol/L Na2SO4＋0.05 mol/L H2SO4 solution by electrochemical *** compared to the coarse grained（CG） counterpart,the UFG alloy exhibits an acceleration of the active dissolution and a shrunk passive region with a higher passive *** Mott-Schottky analysis in conjunction with the point defect model indicates mat the donor diffusion coefficient in the passive films of the UFG sample increases greatly to one magnitude order higher and the donor density is slightly lower than that of the CG sample.

关键词： stainless steel Fe-Ni-Cr polarization acid corrosion passivation

Solar Radiation, Perelman Entropy Mapping, DNA, Viruses etc.

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Open Journal of Biophysics 2020年第2期10卷 54-58页

作者： Kai w. w.ng Peter C. w. Fung wan K. Chow Department of Physics and Astronomy University of Kansas Lawrence USA Department of Physics Department of Medicine and Centre on Behavioral Health University of Hong Kong Hong Kong China Department of Building Services Engineering The Hong Kong Polytechnic University Hong Kong China

A short note based on the homogeneous 5D space-time topological mappings is extended to cover DNAs of viruses and how the body’s immune system can be enhanced to recognize and remove it.

关键词： 5D Homogeneous Space-Time and Perelman Mappings Nitrogenous Bases DNA Viruses Coronavirus Immune System

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软件攻坚术:速成原型与知识工程的结合

计算机科学 1990年第2期17卷 15-25页

作者： Pamela w.Jordan Karl S.Keller Richard w.Tucker David Vogel 中原

本文提出一种叫做两阶段软件攻坚术的软件开发方法,它是速成原型法与知识工程相结合的产物。使用这种方法能生产功能更多的原型,而所需时间为四个月,而不像传统原型法那样需要2年。文中论及该方法与现有原型法的差别,并以开发美国陆军的... 详细信息

本文提出一种叫做两阶段软件攻坚术的软件开发方法,它是速成原型法与知识工程相结合的产物。使用这种方法能生产功能更多的原型,而所需时间为四个月,而不像传统原型法那样需要2年。文中论及该方法与现有原型法的差别,并以开发美国陆军的 MSES 为例,说明了它的要领和主要做法。最后对该方法提出了几点建议。

关键词：软件开发知识工程软件攻坚术