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A DECOUPLING TWO-GRID METHOD FOR THE STEADY-STATE POISSON-NERNST-PLANCK EQUATIONS

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Journal of Computational Mathematics 2019年第4期37卷 556-578页

作者： ying Yang Benzhuo Lu Yan xie School of Mathematics and Computing Science Guangxi Colleges and Universities Key Laboratory of Data Analysis and Computation Guilin University of Electronic Technology Guilin 541004 China LSEC Institute of Computational Mathematics and Scientific/Engineering Computing the National Center for Mathematics and Interdisciplinary Sciences Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China LSEC Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

Poisson-Nernst-Planck equations are widely used to describe the electrodiffusion of ions in a solvated biomolecular system. Two kinds of two-grid finite element algorithms are proposed to decouple the steady-state Poisson-Nernst-Planck equations by coarse grid finite element approximations. Both theoretical analysis and numerical experiments show the efficiency and effectiveness of the two-grid algorithms for solving Poisson-Nernst-Planck equations.

关键词： Poisson-Nernst-Planck equations Two-grid finite element method Decoupling method Error analysis Gummel iteration

Wax deposition law and OLGA-Based prediction method for multiphase flow in submarine pipelines

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Petroleum 2022年第1期8卷 110-117页

作者： ying xie Jin Meng Diwen Chen School of petroleum engineering Southwest Petroleum UniversityChengdu610500China PipeChina Guangdong Pipe Network Co. LtdGuangdongChina

In this study,the effects of wax deposition on submarine multiphase pipelines are *** order to understand the mechanism of wax deposition in submarine multiphase pipelines,a wax deposition model in a submarine pipeline was established using the OLGA wax deposition module,and key factors influencing this phenomenon were ***,a multifactor impact analysis of wax deposition was performed via the orthogonal test *** results indicated the relative influence of five factors on oil-gas-water three-phase wax deposition,namely,oil flow rate,water content,inlet temperature,gas-oil ratio,and outlet ***,the main influencing factors of wax deposition in a multiphase pipeline flow were extracted,and the wax deposition prediction model was *** wax deposition rate under different operating conditions was simulated using the OLGA wax deposition simulation *** SPSS software was used to perform nonlinear regression analysis under different working *** this manner,the constant terms in the wax deposition prediction model for a submarine multiphase pipeline were *** prediction model could be used to programmatically predict wax deposition along a multiphase pipeline by programming the initial waxing *** using this method,the wax deposition prediction model of an MN submarine multiphase pipeline was obtained under different working *** comparing the predicted and the OLGA simulation results,it was concluded that the established wax deposition model can be used to accurately calculate the wax deposition in a submarine multiphase pipeline within an allowable error *** the physical properties and operating parameters of the conveying medium in a multiphase pipeline are given,the developed oil-gas-water three-phase wax deposition model can be used to predict the distribution of wax deposition in submarine multiphase pipelines without laboratory *** results of this stud

关键词： Submarine multiphase pipeline Wax deposition law OLGA Deposition model

PhIO-mediated Synthesis of Ketones from Aikynes and Alkenes

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Chemical Research in Chinese Universities 2019年第1期35卷 26-32页

作者： WEI ying ZHENG Xiangping xie Xinmiao Center for Molecular Systems and Organic Devices(CMSOD) Key Laboratory for Organic Electronics and Information Displays &Jiangsu Key Laboratory for BiosensorsInstitute of Advaneed Materials(LAM) Jiangsu National Synergetie Innovation Center for Advaneed Materials(SICAM) Nanjing University of Posts & TelecommunicationsNanjing 210023P.R.China

A facile and efficient method for the preparation of methyl ketones was developed in the reaction of alkynes and alkenes with PhIO-BF3·*** reaction features mild conditions,short time and metal-free *** possible mech... 详细信息

关键词： Alkyne Alkene Ketone Hydration reaction

Wilson's Disease in China

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Neuroscience Bulletin 2017年第3期33卷 323-330页

作者： Juan-Juan xie Zhi-ying Wu Department of Neurology and Research Center of Neurologyin the Second Affiliated Hospital and the Collaborative Innovation Center for Brain ScienceZhejiang University School of MedicineHangzhou 310009China

Wilson＇s disease（WD） is an autosomal recessive disorder of copper metabolism. Its incidence is higher in China than in western countries. ATP7 B is the causative gene and encodes a P-type ATPase, which participates in the synthesis of holoceruloplasmin and copper excretion. Disease-causing variants of ATP7 B disrupt the normal structure or function of the enzyme and cause copper deposition in multiple organs,leading to diverse clinical manifestations. Given the variety of presentations, misdiagnosis is not rare. Genetic diagnosis plays an important role and has gradually become a routine test in China. The first Chinese spectrum of disease-causing mutations of ATP7 B has been established. As a remediable hereditary disorder, most WD patients have a good prognosis with an early diagnosis and chelation treatment. However, clinical trials are relatively few in China, and most treatments are based on the experience of experts and evidences from other countries. It is necessary to study and develop appropriate regimens specific for Chinese WD patients.

关键词： Wilson’s Disease Copper Epidemiology Pathogenesis Management

Use of near-infrared spectroscopy and least-squares support vector machine to determine quality change of tomato juice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第6期10卷 465-471页

作者： Li-juan xie Yi-bin ying College of Biosystems Engineering and Food Science Zhejiang University Hangzhou 310029 China

Near-infrared (NIR) transmittance spectroscopy combined with least-squares support vector machine (LS-SVM) was investigated to study the quality change of tomato juice during the storage. A total of 100 tomato juice samples were used. The spectrum of each tomato juice was collected twice: the first measurement was taken when the tomato juice was fresh and had not undergone any changes, and the second measurement was taken after a month. Principal component analysis (PCA) was used to examine a potential capability of separating juice before and after the storage. The soluble solid content (SSC) and pH of the juice samples were determined. The results show that changes in certain compounds between tomato juice before and after the storage period were obvious. An excellent precision was achieved by LS-SVM model compared with discriminant partial least-squares (DPLS), soft independent modeling of class analogy (SIMCA), and discriminant analysis (DA) models, with 100% of a total accuracy. It can be found that NIR spectroscopy coupled with LS-SVM, DPLS, SIMCA, and DA can be used to control the quality change of tomato juice during the storage.

关键词： Near-infrared (NIR) spectroscopy Least squares-support vector machine (LS-SVM) Quality change Tomato juice

Direction of Arrivals Estimation for Correlated Broadband Radio Signals by MVDR Algorithm Using Wavelet

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China Communications 2017年第3期14卷 190-197页

作者： ying Liu Chi xie Yourun Zhang School of Energy Science and Engineering University of Electronic Science and Technology of China Chengdu 611731 China Department of Mechanical Engineering Jincheng College of Sichuan University Chengdu 611731 China School of Microelectronics and Solid-State Electronics University of Electronic Science and Technology of China

A theoretical relationship between the wavelet transform and the fast fourier transformation(FFT) methods in broadband wireless signal is proposed for solving the direction of arrivals(DOAs) estimation problem. This leads naturally to the derivation of minimum variance distortionless response(MVDR) algorithm, which combines the benefits of subspace methods with those of wavelet, and spatially smoothed versions are utilized which exhibits good performance against correlated signals. We test the method's performance by simulating and comparing the performance of proposed algorithm, FFT MVDR and MVDR with correlated signals, and an improved performance is obtained.

关键词： array antenna broadband radio signal direction of arrival MVDR algorithm wavelet

Geographical differences of leaf traits of the endangered plant Litsea coreana *** and its relationship with climate

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Journal of Forestry Research 2023年第1期34卷 125-135页

作者： Gangyi Yuan Qiqiang Guo Yaqin Zhang Qin gui Na xie Siqiong Luo Institute for Forest Resources and Environment of guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceCollege of ForestryGuizhou UniversityGuiyang 550025People’s Republic of China

Seventeen morphological and anatomical characteristics of the leaves were selected from five natural populations to explore the variation in leaf traits of Lits ea core ana *** and the effects of geographical environment on these *** analysis of variance,multiple comparisons,principal component analysis(PCA),and correlation analysis were conducted to explore the variations within and between populations and their correlation with geographical and climatic *** differences in the 17 leaf traits were observed within and among *** average,the relative contribution of within population variation to total variation was 24.8%,which was lower than among population variation(54.6%).The average differentiation coefficient of the traits was 65.8%,and the average coefficient of variation 11.8%,ranging from6.7%for main vein thickness to 21.4%for petiole *** PC A results showed that morphological characteristics were divided into two categories,and the level of variation was greater than that of leaf *** of the leaf traits were significantly correlated with geography and climate and showed a gradual variation with longitude,latitude,and *** areas with high temperatures,less rainfall,and strong seasonal rainfall,the leaves are larger,longer and *** study shows that variations in leaf traits of *** *** mainly come from variations among *** level of trait differentiation among populations is high and the level of variation within populations *** findings help further understand leaf morphological characteristics of this species and can provide a valuable reference for the protection and sustainable utilization of this natural resource.

关键词： Litsea coreana var.sinensis Climate Leaf trait variations Natural populations Endangered species

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Synthesis, characterization, theoretical investigation, and properties of monoclinic-phase InWO4 hollow nanospheres

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Nano Research 2018年第9期11卷 4664-4672页

作者： Yuping Wang Di Wang ying xie Guofeng Wang Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials ScienceHeilongjiang University Harbin 150080 China

As a newly discovered member of the ttmgstate famil3~ InWO4 hollow nanospheres with a monoclinic wolframite structure were synthesized successfully. The crystal phase of InWO4 was investigated via a combination of CASTEP geometric optimization and experimental simulation. InWO, has a space group of P2/c with two InWO, formula units per unit cell. The optimized cell dimensions are a = 5.16 A, b = 5.97 A, and c = 5.23 A, with a = 90°, β= 92.11°, 7 = 90°, giving a unit cell volume of 161.10 A^3, which is consistent with the experimental measurements. More importantly, InWO4 was a promising host material for different Ln^3＋（Ln = Eu and Yb/Er） ions. For InWO4：Yb^3＋/Er^3＋ excited at 980 nm, transitions from the ^4G11/2 （384 nm）, ^2H9/2 （411 nm）, and ^4F7/2 （487 nm） levels to the ground state （^4I15/2） of Er^3＋ were observed. In addition to the aforementioned properties, the InWO4 hollow nanospheres can be used to improve the performance of dye-sensitized solar cells, which is chiefly attributed to their light scattering.

关键词： InWO4 rare earth hollow nanospheres luminescence

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 249-256页

作者： Qing-Yun Fang Chengyihan Gu yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han Jin xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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