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Advances in Applied Mathematics and Mechanics 2022年第2期14卷 315-343页

作者： Junpu Li Zhuojia Fu Yan Gu Qing-hua Qin School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhouHenan 450001China College of Mechanics and Materials Hohai UniversityNanjingJiangsu 211100China College of Mathematics Qingdao UniversityQingdaoShandong 266071China College of Engineering and Computer Science Australian National UniversityCanberra ACT 2601Australia

With the rapid development of computer technology,numerical simulation has become the third scientiﬁc research tool besides theoretical analysis and experi-mental *** the core of numerical simulation,constructing efﬁcient,accurate and stable numerical methods to simulate complex scientiﬁc and engineering prob-lems has become a key issue in computational *** article outlines the ap-plication of singular boundary method to the large-scale and high-frequency acoustic *** practical application,the key issue is to construct efﬁcient and accurate numerical methodology to calculate the large-scale and high-frequency soundﬁ*** article focuses on the following two research *** are how to discretize partial differential equations into more appropriate linear equations,and how to solve linear equations more efﬁ*** bottle neck problems encountered in the compu-tational acoustics are used as the technical routes,i.e.,efﬁcient solution of dense linear system composed of ill-conditioned matrix and stable simulation of wave propagation at low sampling *** article reviews recent advances in emerging appli-cations of the singular boundary method for computational *** collection can provide a reference for simulating other more complex wave propagation.

关键词： Singular boundary method origin intensity factor high-frequency acoustic problems large-scale acoustic problems Helmholtz equation

Tb(III) Transport in Dispersion Supported Liquid Membrane System with D2EHPA as Carrier in Kerosene

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Chemical Research in Chinese Universities 2011年第1期27卷 132-139页

作者： PEI Liang YAO Bing-hua WANG Li-ming MA Zhan-ying Faculty of Water Resources and Hydraulic Power Xi ＇an University of Technology Xi ＇an 710048 P. R. China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resource Research Chinese Academy of Sciences Beijing 100101 P. R. China

The transport of Tb（III） in dispersion supported liquid membrane（DSLM） with polyvinylidene fluoride membrane（PVDF） as the support and dispersion solution including HCl solution as the stripping solution and di（2-ethylhexyl） phosphoric acid（D2EHPA） dissolved in kerosene as the membrane solution, has been studied. The effects of pH value, initial concentration of Tb（III） and different ionic strength in the feed phase, volume ratio of membrane solution to stripping solution, concentration of HCl solution, concentration of carrier, different stripping agents in the dispersion phase on the transport of Tb（III） have also been investigated, respectively. As a result, the optimum transport conditions of Tb（III） were obtained, i.e., the concentration of HCl solution was 4.0 mol/L, the concentration of D2EHPA was 0.16 mol/L, the volume ratio of membrane solution to stripping solution was 30：30 in the dispersion phase and pH value was 4.5 in the feed phase. Ionic strength had no obvious effect on the transport of Tb（III）. Under the optimum conditions, the transport percentage of Tb（III） was up to 96.1% in a transport time of 35 min when the initial concentration of Tb（IIl） was 1.0× 10 -4 mol/L. The diffusion coefficient of Tb（III） in the membrane and the thickness of diffusion layer between feed phase and membrane phase were obtained and the values were 1.82×10 -8 m2/s and 5.61 um, respectively. The calculated results were in good agreement with the literature data.

关键词： Dispersion supported liquid membrane Di(2-ethylhexyl) phosphoric acid Terbium(III) Dispersion phase Transport flux Transport percentage

Synthesis, Structure, and Optical Limiting Properties of an Axial Substituted Bis(8-oxide quinoline)zirconium Phthalocyanine

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Chinese Journal of Structural Chemistry 2018年第12期37卷 1971-1978,1846页

作者： YOU Ming-hua FANG Xin LIN Mei-Jin College of Zhicheng Fuzhou University College of Chemistry Fuzhou University

A novel bis(8-oxide quinoline)zironium phthalocyanine [(OQ)2 Zr Pc] with two 8-oxide quinolone anions at the same axial positions has been successfully synthesized and its chemical structure has been assigned by the 1 H NMR, MS and two-dimensional correlation infrared(2D-IR) spectroscopy as well as by single-crystal X-ray structural analysis. It possessed a moderately effective nonlinear absorption coefficient βeff of 6.69×10-14cm/GW at 532 nm in DMF solution, implying it is a promising candidate for nonlinear optical materials.

关键词： phthalocyanines zirconium complex axial substitution single-crystal structure optical limiting properties

A Computational Investigation of the Group Effect of Pits on the Ultimate Strength of Steel Plates

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China Ocean Engineering 2018年第6期32卷 665-674页

作者： FU Qiang FANG Hui WU Ren-xia YU Xue-hui LI hua-jun Institute of Coastal and Offshore Engineering School of Engineering Ocean University of China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace Engineering Xi'an Jiaotong University

In this work, we focus on assessing the group effect of localized corrosion on the ultimate strength of the marine structural plates and study the load-deformation behaviors of plates of various slenderness and uniaxial ***, we investigate different corroded patterns from a single circular pit to 25 circular pits distributed over the plate and carry out hundreds of nonlinear finite element simulations by combining the number, depth, distribution of pits with imperfections and slenderness of plate. The distribution of multiple pits causes scattering of stress concentration on the plate, then the plastic section of plate changes with wider distribution of damage simultaneously. The ultimate strength arises when un-loading zone comprised of the yielding strips and holes extends across the plate. It can be concluded that the corroded condition defined as group effect of pits manipulates the deformation state and the loading capacity of plate at the ultimate strength mode that coincides with the proportion of effective loading area and section in the process of post-buckling. To validate the effect of pits group, we perform the numerical experiments of the post-buckling of steel plates containing pits in a row with different orientation.

关键词： group effect localized corrosion post-buckling ultimate strength

Value of contrast-enhanced ultrasound in deep angiomyxoma using a biplane transrectal probe:A case report

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World Journal of Gastroenterology 2023年第26期29卷 4214-4221页

作者： Qiong Zhang hua-Lin Yan Qiang Lu Yan Luo Department of Medical Ultrasound West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Deep angiomyxoma(DAM)is a very rare tumor *** resonance imaging(MRI)is considered the best imaging modality for diagnosing *** tomography(CT)is used mainly to assess the invasion range of *** value of ultrasonography in the diagnosis of DAM is still *** a literature review,we summarized the current state of ultrasonic examination for DAM and reported for the first time the contrast-enhanced ultrasound(CEUS)features of DAM seen using a biplane transrectal *** SUMMARY A 37-year-old woman presented with a sacrococcygeal mass that had gradually increased in size over the previous 6 *** and CT examinations failed to allow a definite diagnosis to be *** core needle biopsy(CNB)guided by transrectal ultrasound and CEUS was suggested after a multidisciplinary *** ultrasound of the lesion showed a layered appearance with alternating hyperechoic and hypoechoic *** CEUS showed a laminated distribution of the contrast agent that was consistent with the layered appearance of the tumor on grayscale *** performed transperineal CNB of the enhanced area inside the tumor under transrectal CEUS guidance and finally made a definitive diagnosis of DAM through *** patient underwent laparoscopic-assisted transabdominal surgery combined with transperineal surgery for large pelvic tumor resection and pelvic floor peritoneal *** recurrence or metastasis was found at the ninemonth *** Transrectal CEUS can show the layered perfusion characteristics of the contrast agent,guiding subsequent transperineal CNB of the enhanced area within the DAM.

关键词： Contrast-enhanced ultrasound Transrectal ultrasound Transperineal core needle biopsy Deep angiomyxoma Pelvic tumor Case report

Impact of variations of threshold voltage and hold voltage of threshold switching selectors in 1S1R crossbar array

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Chinese Physics B 2018年第11期27卷 630-633页

作者： Yu-Jia Li hua-Qiang Wu Bin Gao Qi-Lin hua Zhao Zhang Wan-Rong Zhang He Qian Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Institute of Microelectronics Tsinghua UniversityBeijing 100084China

The impact of the variations of threshold voltage(V_(th))and hold voltage(V_(hold))of threshold switching(TS)selector in1 S1 R crossbar array is *** on ON/OFF state I–V curves measurements from a large number of Ag-filament TS selectors,V_(th)and V_(hold)are extracted and their variations distribution expressions are obtained,which are then employed to evaluate the impact on read process and write process in 32×321 S1 R crossbar array under different bias *** results indicate that V_(th)and V_(hold)variations of TS selector can lead to degradation of 1 S1 R array performance parameters,such as minimum read/write voltage,bit error rate(BER),and power *** the read process,a small V_(hold)variation not only results in the minimum read voltage increasing but it also leads to serious degradation of *** the standard deviation of V_(hold)and V_(th)increases,the BER and the power consumption of 1 S1 R crossbar array under 1/2 bias,1/3 bias,and floating scheme degrade,and the case under 1/2 bias tends to be more serious compared with other two *** the write process,the minimum write voltage also increases with the variation of V_(hold)from small to large value.A slight increase of V_(th)standard deviation not only decreases write power efficiency markedly but also increases write power *** results have reference significance to understand the voltage variation impacts and design of selector properly.

关键词： RRAM threshold switching selector crossbar array variation

Hepatitis B virus infection and intrahepatic cholangiocarcinoma

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World Journal of Gastroenterology 2014年第19期20卷 5721-5729页

作者： hua-Bang Zhou Jing-Yi Hu He-Ping Hu Department I of Hepatobiliary Diseases Eastern Hepatobiliary Surgery HospitalSecond Military Medical University School of Medicine Shanghai Jiao Tong University

Intrahepatic cholangiocarcinoma(ICC)is a devastating malignant tumor arising from the peripheral intrahepatic bile duct *** incidence and mortality of ICC is markedly increasing over the past two decades worldwide,though the cause for this rise in incidence is unclear,thus intensifying the search for alternative etiological agents and pathogenetic ***,primary sclerosing cholangitis,parasitic infection(Opisthorchis viverrini or Clonorchis sinensis),fibropolycystic liver disease,and chemical carcinogen exposure are thought to be the risk factors for ***,the majority of ICC patients do not have any of these risk factors,and none of the established risk factors can explain the recent increasing trend of ***,identifying other risk factors may lead to the prevention and early detection of *** hepatitis B virus(HBV)infection is the predominant cause of hepatocellular carcinoma in HBVendemic *** review discusses the evidence implicating chronic HBV infection as a likely etiology of ICC and the pathogenetic mechanisms that might be involved.

关键词： Hepatitis B virus Intrahepatic cholangiocarcinoma Epidemiology Etiopathogenesis

A membrane-inspired algorithm with a memory mechanism for knapsack problems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第8期14卷 612-622页

作者： Juan-juan HE Jian-hua XIAO Xiao-long SHI Tao SONG Key Laboratory of Image Processing and Intelligent Control School of AutomationHuazhong University of Science and Technology The Logistics Research Center Nankai University

Membrane algorithms are a class of distributed and parallel algorithms inspired by the structure and behavior of living cells. Many attractive features of living cells have already been abstracted as operators to improve the performance of algorithms. In this work, inspired by the function of biological neuron cells storing information, we consider a memory mechanism by introducing memory modules into a membrane algorithm. The framework of the algorithm consists of two kinds of modules (computation modules and memory modules), both of which are arranged in a ring neighborhood topology. They can store and process information, and exchange information with each other. We test our method on a knapsack problem to demonstrate its feasibility and effectiveness. During the process of approaching the optimum solution, feasible solutions are evolved by rewriting rules in each module, and the information transfers according to directions defined by communication rules. Simulation results showed that the performance of membrane algorithms with memory cells is superior to that of algorithms without memory cells for solving a knapsack problem. Furthermore, the memory mechanism can prevent premature convergence and increase the possibility of finding a global solution.

关键词： Membrane algorithm Memory mechanism Knapsack problem

Horizontal Velocity of Variable Gauge Rolling:Theory and Finite Elements Simulation

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Journal of Iron and Steel Research International 2013年第10期20卷 10-16页

作者： ZHANG Guang-ji LIU Xiang-hua HU Xian-lei ZHI Ying State Key Laboratory of Rolling and Automation Northeastern University

Within the production chain of longitudinal profiled （LP） plates and tailor rolled blanks （TRB）, variable gauge roiling （VGR） represents the vital important forming stage, in which shape and properties are tailored to sat- isfy customers＇ requirements. It is of vital importance to reveal the relationship between work-piece horizontal veloci- ty and roll vertical velocity during VGR, which is not only a key point to understand the deformation law, but also an important content for setting VGR process parameters. It is proved that the simplified assumption of equal dis- charge per second condition （EDSC） breaks down during VGR. Due to this reason the differential equation of the work-piece horizontal velocity （VGR-V） is performed by keeping the material volume constant. To attain a compre- hensive understanding of this underlying process in detail, numerical approaches based on finite elements method have been performed by utilizing the Abaqus Explicit. Rolling experiment is carried out which indicates that the nu- merical result coincides with the expel＇imental result well. A fine spatial discretization of work-piece is essential for special emphasis has to be put on detecting different horizontal velocity of work-piece cross section, often leading to a hundred thousand degrees of freedom even for plane strain calculations. The data obtained by using Abaqus Explicit coincide with the results determined by theory. A theoretical basis on deformation parameters and mechanical param- eters during VGR process is provided.

关键词： variable gauge rolling horizontal velocity non-linear finite element analysis

Electrochemical performance of La_(1-x)Sr_xCuO_(3-δ)-Sm_(0.15)Ce_(0.85)O_(1.925) composite cathodes in IT-SOFCs

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Rare Metals 2006年第Z1期25卷 256-260页

作者： ZHENG Minzhang XIN hua LIU Xiaomei LIU Qian XU Dan SU Wenhui Department of Physics Jilin University Changchun 130023 China College of Tele Communications Engineering Jilin University Changchun 130023 China Department of Physics Jilin University Changchun 130023 China Department of Physics Jilin University Changchun 130023 China 　 Department of Physics Jilin University Changchun 130023 China

The cathode material La1-xSrxCuO3-δ(x=0.15, 0.2, 0.3, 0.4) was synthesized by a sol-gel method. X-ray diffraction reveals that a single phase of perovskite is formed. The investigation of the electrical properties suggests that La0.7Sr0.3CuO3-δ has the highest electrical conductivity. La0.7Sr0.3CuO3-δ powder was mixed with different amount SDC (Sm0.15Ce0.85O1.925) powder (5wt.%-30wt.%) as composite cathodes. Electrochemical properties of the composite cathodes were researched further. Investigation suggests that the addition of appropriate amount SDC to La0.7Sr0.3CuO3-δ can improve the electrochemical properties and obtain better cathodic performance. Using La0.7Sr0.3CuO3-δ-SDC composite materials as a cathode based on SDC electrolyte, higher current density and power density at intermediate temperatures can be obtained.

关键词： SOFC Composite Cathode La1-xSrxCuO3-δ SDC