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Synthesis and Structural Characterization of a New Hydrogen-bonded Polyrotaxane of [Co(H_2O)_6]_(2+) with 1,1′-(Propane-1,3-diyl)dipyridinium-4-carboxylate

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Chinese Journal of Structural Chemistry 2006年第8期25卷 957-964页

作者： JIANG ning-yi LI Song-Lin Department of Chemistry College of Science Tianjin University Tianjin 300072 China

A new double betaine 1,1′-（propane-1,3-diyl）dipyridinium-4-carboxylate L has been synthesized. Reaction of 1, 1′-（propane-1,3-diyl）dipyridinium-4-carboxylate tetrahydrate 1 with Co（ClO4）2-6H2O leads to the formation of a new Co（Ⅱ） coordination compound, namely [Co（H2O）6]-2H2O-2L-2ClO4 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1. monoclinic, space group C2/c, a = 18.945（4）, b = 7.700（2）, c = l 1.888（2）A,β = 101.67（3）°, V = 1698.3（6） A^3, Z = 4, F（000） = 760.0, Dc = 1.402 g/cm^3, the final R = 0.0607 and wR = 0.1607 for 950 observed reflections （1 〉 2σ（I））; and those for 2： monoclinic, space group P21/c, a = 17.982（1）, b = 15.879 （1）, c = 7.0716（5）/A,β= 100.675（1）°, V= 1984.3（3） ,A^3 Z= 4, F（000） = 1010.0, Dc = 1.631 g/cm^3, the final R = 0.0316 and wR = 0.0896 for 3784 observed reflections （1 〉20（I））. Crystal structure analysis indicates that in 1, molecules of L in a ＂V-shaped＂ conformation are linked to chains sustained by O-H…O hydrogen bonds between carboxylate groups and solvent water molecules. The chains are joined by O-H…O and C-H…O hydrogen bonds to further expand into a three-dimensional structure. For 2, molecules of L in a ＂Z-shaped＂ conformation are linked by hydrogen bonds between carboxylate groups and aqua ligands to form a chain of loops running down the b axis. The （2D→2D） polythreading in compound 2 represents the mode of parallel interpenetration of 2D sheets, having polyrotaxane character.

关键词： 1,1′-(propane-1,3-diyl)dipyridinium-4-carboxylate polyrotaxane hydrogen bonding betaine derivative

A quantum integral spectral enhancement method for Xray imaging

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Optoelectronics Letters 2020年第5期16卷 390-395页

作者： ZHU Yan xu ning-xin MU yi-ning WANG He WANG yi-ming REN Hang Department of Electronic Science and Technology Faculty of ScienceChangchun University of Science and TechnologyChangchun 130022China

In order to avoid the effect of photon defect on the imaging during X-ray generation,an imaging integral filter based on quantum enhancement was proposed in this paper to effectively reduce the sensitivity of X-ray detection system for quantum ***,the coupling constraint at the end of the image intensifier was analyzed by discussing the X-ray imaging *** effects of quantum thermal noise and defects on spectrum transfer were studied from the micro *** the effectiveness of the new integral filter method was verified from the view of the integral effect of fundamental space frequency transfer characteristics in Fourier ***,the superior ity and real-time performance of the quantum enhancement filter method were verified by the comparison filter testing.

关键词： mechanism. spectrum. quantum

过表达iNOS基因小鼠模型对日本血吸虫寄生适应性影响的研究

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热带医学杂志 2022年第12期22卷 1611-1615,1620,1757页

作者：赵思雨胡云逸张丽超徐美依宁江可风吴忠道沈佳中山大学中山医学院寄生虫学教研室广东广州510080 中山大学热带病防治研究教育部重点实验室广东广州510080 广东省媒介生物防治研究中心广东广州510080

目的构建细胞、组织特异性过表达一氧化氮合酶(iNOS)基因小鼠模型,观察其基本生理特征,检测该小鼠模型对日本血吸虫寄生适应性的影响,包括虫体的生存发育、产卵及对肝脏病理的影响。方法采用规律成簇的间隔短回文重复及其相关蛋白9(CRIS... 详细信息

目的构建细胞、组织特异性过表达一氧化氮合酶(iNOS)基因小鼠模型,观察其基本生理特征,检测该小鼠模型对日本血吸虫寄生适应性的影响,包括虫体的生存发育、产卵及对肝脏病理的影响。方法采用规律成簇的间隔短回文重复及其相关蛋白9(CRISPR/Cas9)技术将大鼠的iNOS基因片段定点插入到C57小鼠的Rosa26位点,获得F0代Rosa26^(CAG-LSL-Rat iNOS)杂合子小鼠,再分别与LysM^(Cre)、Alb^(Cre)、Tek^(Cre)工具小鼠繁配,构建髓系细胞/内皮细胞/肝脏特异性过表达iNOS基因的基因工程小鼠,即Rosa26^(CAG-LSL-Rat iNOS)LysM/Alb/Tek^(Cre)基因工程小鼠,观察其基本生理特征。随后建立日本血吸虫感染动物模型。感染6周后,灌注法收集虫体并计数,采用碱消化法计数沉积在肝脏组织中的虫卵数量,利用苏木精-伊红(HE)、马松(Masson)及天狼星红染色法观察肝脏虫卵肉芽肿及肝纤维化的情况。结果与C57^(WT)小鼠比较,过表达iNOS基因小鼠的体重、毛色、精神状态及情绪等基本行为学特征差异无统计学意义(P>0.05)。但iNOS基因过表达后会使阳性小鼠的出生率明显减少及引起死亡。在感染日本血吸虫尾蚴后6周,与C57^(WT)小鼠比较,C57^(LysM-iNOS)小鼠体内的虫体数量[(28.1±2.2)条/只vs.8条/只]、肝脏沉积的虫卵数量[(84754±44232)个/克肝脏vs.13825个/克肝脏)]、肝脏虫卵肉芽肿炎症反应[小鼠单个视野肉芽肿数量:(7.2±2.7)个vs.(1.3±0.8)个,P0.05)。结论表达iNOS的髓系细胞是影响日本血吸虫寄生适应性的重要效应细胞,内皮细胞中iNOS的过表达对日本血吸虫寄生适应性的影响较小,而肝脏中特异性高表达iNOS基因可显著减少日本血吸虫感染引起的肝脏虫卵肉芽肿炎症反应和肝纤维化的形成。

关键词： iNOS过表达日本血吸虫宿主适应性 CRISPR/Cas9 细胞特异性

Effect of relaxation time on the squeezed correlations of bosons for evolving sources in relativistic heavy-ion collisions

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Nuclear Science and Techniques 2022年第2期33卷 87-92页

作者： Wei-ning Zhang Peng-Zhi xu School of Physics Dalian University of TechnologyDalian 116024China College of Computer Science and Technology Jilin Normal UniversitySiping 136000China

The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the relaxation time of the *** this study,we investigated the effect of relaxation time on the SBBC *** propose a method for calculating the SBBC function with relaxation-time approximation for evolving *** functions of D^(0)D^(-0)in relativistic heavy-ion collisions were investigated using a hydrodynamic *** found that the relaxation time reduces the amplitudes of the SBBC *** becomes apparent for long relaxation times and large initial relative deviations of the chaotic and squeezed amplitudes from their equilibrium values in the temporal steps.

关键词： Relaxation time Squeezed back-to-back correlation Evolving source Relativistic heavy-ion collisions

Dynamic scaling characteristics of single-phase natural circulation based on different strain transformations

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Nuclear Science and Techniques 2023年第9期34卷 128-141页

作者： Jia-ning xu Xiang-Bin Li Zhong-yi Wang Yu-Sheng Liu De-Chen Zhang Qiao Wu School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy Beijing 102206China China Institute of Nuclear Industry Strategy BeijingChina Nuclear and Radiation Safety Center MEEBeijing 100082China Department of Nuclear Engineering Oregon State UniversityCorvallisOR 97331USA

To understand the dynamical system scaling(DSS)analysis theory,the applicability of DSSβ-andω-strain transformation methods for the scaling analysis of complex loops was explored.A simplified model consisting of two loops was established based on the primary and secondary sides of a nuclear reactor,andβ-andω-strain transformation methods were used to ana-lyze the single-phase natural circulation in the primary *** comparison with the traditional method,simplified DSSβ-andω-strain methods were developed based on the standard scaling *** strain parameters in these four methods were modified to form multiple groups of scaled-down *** transient process of the natural circulation was simulated using the Relap5 code,and the variation in the dynamic flow characteristics with the strain numbers was obtained using different scaling *** results show that both the simplified and standard DSS methods can simulate the dynamic characteristics of natural circulation in the primary *** scaled-down cases in the simplified method exhibit the same geometric scaling and correspond to small core power *** contrast,different scaled-down cases in the standard DSS method correspond to different geometric scaling criteria and require more *** dynamic process of natural circula-tion can be simulated more accurately using the standard DSS method.

关键词： Dynamical system scaling analysis β-strain transformation ω-strain transformation Natural circulation

Numerical simulation of shock wave phenomena in hydrodynamic model of semiconductor devices

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 71-76页

作者： xu ning YANG Geng College of Optical and Electric Engineering Nanjjing University of Posts and Telecommunications Nanjing 210003 China College of Mathematics and Physics Nanking University of Posts and Telecommunications Nanjing 210003 China

We propose a finite element method to investigate the phenomena of shock wave and to simulate the hydrodynamic model in semiconductor devices. An introduction of this model is discussed first. Then some scaling factors and a relationship between the changing variables are discussed. And then, we use a finite element method （P1-iso-P2 element） to discrete the equations. Some boundary conditions are also discussed. Finally, a sub-micron n%＋-n-n^＋ silicon diode and Si MESFET device are simulated and the results are analyzed. Numerical results show that electronic fluids are transonic under some conditions.

关键词： hydrodynamic model semiconductor devices finite element method shock wave

How to build a habitable planet:an interview with Charles H. Langmuir

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National Science Review 2024年第6期11卷 76-80页

作者： yi-Gang xu the Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Earth is the only known habitable planet in the solar system. Understanding how Earth developed its unique habitability has been the frontier of Earth sciences and has become one of the main themes of current deep-space explorations. What are the decisive factors that led to a habitable planet? What is the role of solid Earth processes in the origin of life and in modulating the surface environment? Are Earth’s habitability studies relevant to current challenges that human beings face? These questions have attracted the interest of both scientists and the public alike.

关键词： Earth (planet)

The remarkable effect of amino hydrogen on membrane permeability and organelle staining of 1,8-naphthalimide dyes

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Chinese Chemical Letters 2024年第2期35卷 347-351页

作者： Zhifeng Li Qinglong Qiao ning xu Kai An Wenchao Jiang yi Tao Pengjun Bao yinchan Zhang Zhaochao xu School of Chemistry Dalian University of TechnologyDalian 116024China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Membrane permeability and intracellular diffusion of fluorescent probes determine staining selectivity of intracellular ***,the relationship between the molecular structure of fluorescent probes and their membrane permeability and intracellular distribution is poorly *** this paper,we reported a series of 1,8-naphthalimide dyes and carried out cell imaging experiments,and found that the presence of amino hydrogen in these dyes played a crucial role in their cell membrane permeability and intracellular *** secondary amino group containing compounds 1-4 show excellent membrane permeability and strong fluorescence in living *** the tertiary amine containing dyes 5 and 6 can hardly permeate the cell membrane though they show extremely similar structure with compounds *** 1 can selectively image lipid droplets by selecting the wavelength of excitation *** the specificity for lysosomes,2 and 4 have been used in long-term time-lapses imaging of lysosomal dynamics and tracking the process of lysosome-lysosome interaction,fusion and *** effect of hydrogen-containing amino substituent on the cell membrane permeability of fluorescent molecules is promising for the development of better biocompatible probes.

关键词： Amino hydrogen 1,8-Naphthalimide Cell permeability Lipid droplet Lysosome

The Average Errors for Hermite Interpolation on the 1-Fold Integrated Wiener Space

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Chinese Annals of Mathematics,Series B 2012年第5期33卷 737-750页

作者： Guiqiao xu Jingrui ning Department of Mathematics Tianjin Normal University Tianjin 300387 China.

For the weighted approximation in Lp-norm,the authors determine the weakly asymptotic order for the p-average errors of the sequence of Hermite interpolation based on the Chebyshev nodes on the 1-fold integrated Wiener *** this result,it is known that in the sense of information-based complexity,if permissible information functionals are Hermite data,then the p-average errors of this sequence are weakly equivalent to those of the corresponding sequence of the minimal p-average radius of nonadaptive information.

关键词： Chebyshev polynomial Hermite interpolation Weighted Lp-norm 1-Fold integrated Wiener space