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Syntheses, Crystal Structures and Antimicrobial Activities of Vanadium(V) Complexes with Similar Tridentate Hydrazone Ligands

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Chinese Journal of Structural Chemistry 2015年第6期34卷 885-893页

作者： LI Ke LI Shu-jing YAO Xin-Jian niu jing-jing QIU Xiao-Yang School of Chemistry & Chemical Engineering Zhoukou Normal University Department of Chemistry Shangqiu Normal University

Two hydrazone ligands （E）-N＇-（2-hydroxy-5-methoxybenzylidene）-2-hydroxybenzo- hydrazide （HLa） and （E）-N＇-（3,5-dichloro-2- hydroxybenzylidene）-4-methoxybenzohydrazide （HLb） were prepared and characterized by IR, UV-Vis and 1H NMR spectra. Based on the hydrazone ligands, two new structurally similar vanadium（V） complexes, [VOLaL].CH3OH （1） and [vOLbL] （2）, where L is the monoanionic form of benzohydroxamic acid （HL）, were prepared and characterized by IR and UV-Vis spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes as the monoclinic space group P21/n, with a = 7.5208（10）, b = 15.490（2）, c = 20.8929（18） A, β = 96.373（2）°, V = 2418.9（5） A3, Z = 4, R = 0.0831, wR = 0.2607 and GOOF = 1.061. Complex 2 crystallizes as the monoclinic space group P21/c, with a = 11.8577（18）, b = 16.468（2）, c = 12.2288（18） A, β = 106.064（2）°, V= 2294.7（6） A3, Z = 4, R= 0.0741, wR= 0.1745 and GOOF= 1.014. X-ray analysis indicates that the complexes are mononuclear vanadium （V） species, with the V atoms located in the octahedral coordination. The hydrazone ligands and the complexes were evaluated for their antibacterial （Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescence） and antifungal （Candida albicans and Aspergillus niger） activities by MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide） method.

关键词： hydrazone vanadium complex mononuclear complex crystal structure antimicrobial activity

Simple aspects of femtosecond stimulated Raman spectroscopy

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Science China Chemistry 2011年第12期54卷 1989-2008页

作者： ZHAO bin niu Kai LI XiuTing LEE Soo-Ying Division of Physics ＆ Applied Physics School of Physical ＆ Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore Division of Chemistry ＆ Biological Chemistry School of Physical ＆ Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore

Femtosecond stimulated Raman spectroscopy （FSRS）, using an overlapping pair of narrow band Raman pump and broadband probe pulses with heterodyne detection along the probe pulse direction, is a new nonlinear spectroscopic technique to record vibrational spectra of even highly fluorescent molecules and to study vibrational dynamics on excited electronic states of molecules, as in photoisomerization. FSRS is described by diagrammatic third-order perturbation theory with wave packet analysis. The phase matching condition gives rise to forty-eight terms for FSRS, but the resonant condition reduces it to just eight terms, which can be depicted by Feynman dual time-line diagrams, or closed time path loop diagrams, or the complementary four-wave mixing energy level diagrams. The eight terms fall into four sets-SRS（I）, SRS（Ⅱ）, IRS（I）, IRS（Ⅱ）-where SRS stands for stimulated Raman scattering and IRS stands for inverse Raman scattering. The SRS（I） set can also account for spontaneous Raman scattering, but the remaining SRS（Ⅱ）, IRS（I） and IRS（Ⅱ） terms are only present in stimulated scattering with the presence of a probe field. The SRS（I） set accounts for the Stokes Raman lines while the IRS（I） term accounts for the anti-Stokes lines, relative to the Raman pump frequency, in the FSRS spectrum. The remaining SRS（Ⅱ） and IRS（Ⅱ） terms give rise to broad baselines. Using a harmonic oscillator model, analytic results are obtained for the four-time correlation functions in the third-order polarizations. The issue of high time and high frequency resolution in time-resolved FSRS spectra is discussed. Calculations are made with the theory to compare with experimental results for：（a） resonance FSRS of fluorescent Rhodamine 6G and （b） 2D-FSRS from a coherent vibrational state that has been prepared by an impulsive, off-resonant pump pulse on CDCl3. The calculated results compared well with experimental results, and in the case of 2D-FSRS on CDCl3 there is a dominant cascade effect contribu

关键词： femtosecond stimulated Raman spectroscopy temporal and spectral resolution cascade effect

Suspension Polymerization of Methyl Methacrylate Stabilized Solely by Palygorskite Nano Fibers

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Chinese Journal of Polymer Science 2014年第2期32卷 123-123,124-129页

作者：黎白钰 Yin-ping Wang Xiao-bin niu Zai-man Liu The School of Chemical & Biological Engineering Lanzhou Jiaotong University

A kind of fibrous clay, palygorskite （PAL）, was used as the sole stabilizer in suspension polymerization without the using of any other stabilizer usually used, especially polymeric stabilizers. In order to improve the compatibility with the organic monomer, PAL nano fibers were organically modified with silane coupling agent methacryloxypropyltrimethoxysilane （MPS）. Transmission electron microscopy （TEM） and Fourier-transform infrared （FTIR） spectroscopy results show that the hydrolyzed MPS was attached onto PAL surface through Si--O--Si bonds formation without morphology change of PAL. At a loading amount of PAL to monomer as low as 0.36 wt%, effective stabilization could be achieved. After suspension polymerization, spherical poly（methyl methacrylate）（PMMA） particles were obtained. Scanning electron microscopy （SEM） analysis on both the outer surface and the inner cracked surface of the spherical PMMA particles indicates that the PAL particles reside on the surface of the PMMA spheres. The densely stacked PAL together with attached silane coupling agent stabilized the droplets throughout the suspension polymerization.

关键词： Palygorskite Attapulgite Clay Poly(methyl methacrylate) Suspension polymerization.

Combined thrombectomy and intracoronary administration of glycoprotein IIb/IIIa inhibitors improves myocardial reperfusion in patients undergoing primary percutaneous coronary intervention： a meta-analysis

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Journal of Geriatric Cardiology 2017年第10期14卷 614-623页

作者： Xiao-Wei niu jing-jing ZHANG Ming BAI Yu PENG Zheng ZHANG The First Clinical Medical School Lanzhou University Lanzhou China Baiyin Second People's Hospital Baiyin China Department of Cardiology the First Hospital of Lanzhou University Lanzhou China

Background Suboptimal myocardial reperfusion is common in patients with ST-segment elevation myocardial infarction （STEMI） undergoing primary percutaneous coronary intervention （PPCI）. Furthermore, it results in increased infarct size and mortality rates. We performed a meta-analysis to evaluate the role of aspiration thrombectomy （AT） combined with intracoronary administration of glycoprotein IIb/IIIa inhibitors （GPI） in the improvement of myocardial reperfusion and clinical outcomes. Methods PubMed, Embase, Web of Science, and CENTRAL databases were searched for randomized controlled trials （RCTs） investigating combined AT and intracoronary GPI treatment versus AT alone. Outcomes of interest were thrombolysis in myocardial infarction myocardial perfusion grade （TMPG）, infarct size （IS） assessed by cardiac magnetic resonance imaging, left ventricular ejection fraction （LVEF）, major adverse cardiac events （MACE） at short-term （〈 1 month） and long-term （6-12 months） follow-up, and bleeding complications during the hospital stay. Results Eight trials involving 923 patients were included. Compared with AT alone, combined AT and intracoronary GPI significantly increased TMPG 3 flow （RR： 1.15, 95% CI： 1.04 to 1.26）, reduced IS [mean difference （MD）： -3.46, 95% CI： -5.18 to -1.73], and improved LVEF （MD： 1.44, 95% CI： 0.54 to 2.33）. Furthermore, GPI use decreased the risk of MACE at long-term follow-up （RR： 0.60, 95% CI： 0.37 to 0.98）. There was no significant difference between the two groups in the incidence of minor and major bleeding complications. Conclusions Our findings showed that compared with AT alone, combined AT and intracoronary GPI treatment resulted in improved myocardial reperfusion, better cardiac function, and MACE-free survival benefits at the long-term follow-up for patients with STEMI undergoing PPCI.

关键词： Glycoprotein llb/IIIa inhibitors Meta-analysis Myocardial reperfusion Thrombectomy Percutaneous coronary intervention

Latest developments in precancerous lesions of hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第12期22卷 3305-3314页

作者： Zhao-Shan niu Xiao-Jun niu Wen-Hong Wang jing Zhao Laboratory of Micromorphology Medical College of Qingdao University Clinical Medicine Specialty Medical College of Qingdao University Department of Pathology Medical College of Qingdao University Department of Pathology the Affiliated Hospital of Qingdao University

Hepatocarcinogenesis in human chronic liver diseases is a multi-step process in which hepatic precancerous lesions progress into early hepatocellular carcinoma(HCC) and progressed HCC, and the close surveillance and treatment of these lesions will help improve the survival rates of patients with HCC. The rapid development and extensive application of imaging technology have facilitated the discovery of nodular lesions of ambiguous significance, such as dysplastic nodules. Further investigations showed that these nodules may be hepatic precancerous lesions, and they often appear in patients with liver cirrhosis. Although the morphology of these nodules is not sufficient to support a diagnosis of malignant tumor, these nodules are closely correlated with the occurrence of HCC, as indicated by long-term follow-up studies. In recent years, the rapid development and wide application of pathology, molecular genetics and imaging technology have elucidated the characteristics of precancerous lesions. Based on our extensive review of the relevant literature, this article focuses on evidence indicating that high-grade dysplastic nodules are more likely to transform into HCC than low-grade dysplastic nodules based on clinical, pathological, molecular genetic and radiological assessments. In addition, evidence supporting the precancerous nature of large cell change in hepatitis B virus-related HCC is discussed.

关键词： Hepatocellular carcinoma Precancerous lesions High-grade dysplastic nodule Large cell change Small cell change

Progress in Bio‑inspired Anti‑solid Particle Erosion Materials:Learning from Nature but Going beyond Nature

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Chinese Journal of Mechanical Engineering 2020年第3期33卷 5-31页

作者： Shuaijun Zhang Junqiu Zhang bin Zhu Shichao niu Zhiwu Han Luquan Ren Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun 130022China Department of Mechanical Engineering Sciences University of SurreyGuildfordSurrey GU27XHUK.

Solid particle erosion is a common phenomenon in engineering fields,such as manufacturing,energy,military and ***,with the rising industrial requirements,the development of anti-solid particle erosion materials remains a great *** billions of years of evolution,several natural materials exhibit unique and exceptional solid particle erosion *** materials achieved the same excellent solid particle erosion resistance performance through diversified *** resistance arises from their micro/nanoscale surface structure and interface material properties,which provide inspiration for novel multiple solutions to solid particle ***,this review first summarizes the recent significant process in the research of natural anti-solid particle erosion materials and their general design *** to these principles,several erosion-resistant structures are *** with advanced micro/nanomanufacturing technologies,several artificial anti-solid particle erosion materials have been ***,the potential applications of anti-solid particle erosion materials are ***,the remaining challenges and promising breakthroughs regarding anti-solid particle erosion materials are briefly discussed.

关键词： Bio-inspired materials Solid particle erosion Surface structures Micro/nanomanufacturing technologies Applications

Hydrothermal Synthesis and Crystal Structure of a New 2D Layer Compound [{Ni(en)_2}_2Sb_8V_(14)O_(42)]·5.5H_2O

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Chemical Research in Chinese Universities 2009年第4期25卷 426-429页

作者： YU Li LIU Jiang-ping WANG jing-ping niu jing-yang Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Ifenan University Kaifeng 475001 P. R. China

A new compound based on polyoxovanadate [{Ni（en）2}2Sb8V14O42]·5.5H2O（en=ethylenediamine）（1） was synthesised hydrothermally as black rhombus *** 1 crystallized in the monoclinic system with space group P21/n,Z=4,a=1.46953（9） nm,b=1.28623（8） nm,c=1.76008（11） nm,β=105.7230（10）°.In the asymmetric unit,cluster {Sb8V14O42} can be considered as an Sb derivative of the {V18O42} *** {Sb8V14O42} cluster as a building block interconnected to four other neighboring units by {Ni（en）2} bridging groups which are linked through the terminal oxygen atoms of the polyoxoanions,forming a two dimensional network.

关键词： Hydrothermal synthesis Antimony-substituted Polyoxovanadate

Hybrid Tungstocuprate [Cu(2,2′-bpy)_3]_2H_4[CuW_(12)O_(40)]·6H_2O Based on Keggin Polyoxoanion [CuW_(12)O_(40)]^(6-) with Cu~Ⅱas Heteroatom

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Chemical Research in Chinese Universities 2007年第3期23卷 263-267页

作者： WANG jing-ping MA Peng-tao LI Jie niu jing-yang Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 P. R. China

A novel hybrid tungstocuprate （ Ⅱ ） [ Cu （2,2＇-bpy） 3 ] 2 H4 [ CuW12O40 ] · 6H2O （ 2,2＇-bpy = 2,2＇-bipyfidine） was synthesized via hydrothermal method and characterized using elemental analyses, IR, UV, XPS, TG-DSC, EPR, and X-ray single crystal diffraction. The structural analysis shows that the complex consists of an unusual Keggin-type polyoxoanion [ CuW12O40 ]^6- and a pair of chiral complex cations [ Cu（2,2＇-bpy） 3 ]^＋ together with four protons and six crystallization water molecules, and the Keggin polyoxoanion is connected with [ Cu （2,2＇-bpy）3 ]^＋v/a multiple C-H…O hydrogen bonds resulting in a dimer.

关键词： Hydrothermal synthesis Polyoxometalates Keggin Tungstocuprate

A Review of Intelligent Configuration and Its Security for Complex Networks

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Chinese Journal of Electronics 2024年第4期33卷 920-947页

作者： Yue ZHAO bin YANG Fei TENG Xianhua niu Ning HU Bo TIAN Science and Technology on Communication Security Laboratory School of Computer and Information Engineering Chuzhou University School of Computing and Artificial Intelligence Southwest Jiaotong University School of Computer and Software Engineering Xihua University Cyberspace Institute of Advanced Technology Guangzhou University

Complex networks are becoming more complex because of the use of many components with diverse technologies. In fact, manual configuration that makes each component interoperable has breed latent danger to system security. There is still no comprehensive review of these studies and prospects for further research. According to the complexity of component configuration and difficulty of security assurance in typical complex networks, this paper systematically reviews the abstract models and formal analysis methods required for intelligent configuration of complex networks, specifically analyzes, and compares the current key technologies such as configuration semantic awareness, automatic generation of security configuration, dynamic deployment, and verification evaluation. These technologies can effectively improve the security of complex networks intelligent configuration and reduce the complexity of operation and maintenance. This paper also summarizes the mainstream construction methods of complex networks configuration and its security test environment and detection index system, which lays a theoretical foundation for the formation of the comprehensive effectiveness verification capability of configuration security. The whole lifecycle management system of configuration security process proposed in this paper provides an important technical reference for reducing the complexity of network operation and maintenance and improving network security.

关键词： Complex networks Intelligent configuration Configuration security Software defined network Lifecycle management