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Hydrothermal Synthesis and Structure Characterization of Compound Zn(Hpydc)_2(H_2O) (pydc=pyridine-2,5-dicarboxylate)

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Chinese Journal of Structural Chemistry 2001年第6期20卷 455-458页

作者：梁玉仓江茂椿等中科院福建物质结构所结构化学国家重点实验室福建福州 350002

The hydrothermal reaction of ZnO, H3PO4(85%), (H2NCH2CH2)2NH and H2pydc results in the formation of a discrete mononuclear zinc(II) complex Zn(Hpydc)2(H2O). It crystallizes in monoclinic space group C2/c with a = 17.9947(8), b = 7.1875(3), c = 12.5895(4) , b = 110.802(2), V = 1522.14(10) 3, Z = 4, Mr = 415.61, (C14H10N2O9Zn), Dc = 1.814g/cm3, = 16.71cm-1, F(000) = 840, R = 0.0505, wR = 0.1144. Each zinc(II) is coordinated to two nitrogen and three oxygen atoms of which two nitrogen and two oxygen atoms are from two pydc ligands, and one oxygen atom from the coordinated water molecule to form an irregular polyhedral geometry. The complex is linked further into a three-dimensional structure through the weak interactions of hydrogen bonds between the two oxygen atoms. IR spectrum of the complex is also discussed.

关键词： zinc complex hydrothermal synthesis crystal structure hydrogen bond weak interaction

Asymptotics of discounted aggregate claims for renewal risk model with risky investment

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Applied Mathematics(A Journal of Chinese Universities) 2010年第2期25卷 209-216页

作者： JIANG Tao School of Finance, Zhejiang Gongshang University, Hangzhou 310018, china School of Finance Zhejiang Gongshang University Hangzhou China

Under the assumption that the claim size is subexponentially distributed and the insurance surplus is totally invested in risky asset, a simple asymptotic relation of tail probability of discounted aggregate claims for renewal risk model within finite horizon is obtained. The result extends the corresponding conclusions of related references.

关键词： Discounted aggregate claims ruin probability within finite horizon renewal risk model risky investment subexponential class.

Crystallization characteristics of Ni-W-P composite coatings reinforced by CeO_2 and SiO_2 nano-particles

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Journal of Central South University 2014年第12期21卷 4424-4431页

作者：徐瑞东翟大成章俞之 State key Laboratory of Complex Nonferrous Metal Resources Clean Utilization(Kunming University of Science and Technology) Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology key Laboratory of Inorganic Coating Materials Chinese Academy of Sciences

Ni-W-P composite coatings reinforced by Ce O2 and Si O2 nano-particles on the surface of common carbon steels, were prepared by double pulse electrodeposition. The crystallization course was characterized by phase structures, crystallinity, grain sizes and microstructures. The results indicate that as-deposited composite coating is amorphous. Whereas it turns into the crystalline structure with 98.25% crystallinity, and Ni3 P, Ni2 P and Ni5P2 alloy phases precipitate from structures at 400 °C. Thereafter, Ni2 P and Ni5P2 metastable alloy phases turn into Ni3 P stable alloy phase at 500 °C. The crystallization course of the composite coating has finished when being heat-treated at 700 °C. The average sizes of Ni grains increase with the rise of heat treatment temperature from400 °C to 700 °C. Ce O2 and Si O2 nano-particles deposited into Ni-W-P alloys can delay the crystallization course and habit the growth of alloy phases.

关键词： composite coating double pulse electrodeposition Ni-W-P nano-particles crystallization characteristics

Loss of VAPB Regulates Autophagy in a Beclin 1-Dependent Manner

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Neuroscience Bulletin 2018年第6期34卷 1037-1046页

作者： Dan Wu Zongbing Hao Haigang Ren Guanghui Wang Laboratory of Molecular Neuropathology Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences Soochow University

Autophagy is an evolutionarily-conserved selfdegradative process that maintains cellular homeostasis by eliminating protein aggregates and damaged ***, vesicle-associated membrane protein-associated protein B(VAPB), which is associated with the familial form of amyotrophic lateral sclerosis, has been shown to regulate autophagy. In the present study, we demonstrated that knockdown of VAPB induced the up-regulation of beclin 1 expression, which promoted LC3(microtubuleassociated protein light chain 3) conversion and the formation of LC3 puncta, whereas overexpression of VAPB inhibited these processes. The regulation of beclin1 by VAPB was at the transcriptional level. Moreover,knockdown of VAPB increased autophagic flux, which promoted the degradation of the autophagy substrate p62 and neurodegenerative disease proteins. Our study provides evidence that the regulation of autophagy by VAPB is associated with the autophagy-initiating factor beclin 1.

关键词： VAPB Autophagy Beclin 1 ALS Autophagic flux LC3

Global Well-Posedness of Incompressible Navier-Stokes Equations with Two Slow Variables

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Chinese Annals of Mathematics,Series B 2017年第3期38卷 787-794页

作者： Weimin PENG Yi ZHOU College of Science University of Shanghai for Science and Technology School of Mathematical sciences Fudan University

In this paper, the global well-posedness of the three-dimensional incompressible Navier-Stokes equations with a linear damping for a class of large initial data slowly varying in two directions are proved by means of ... 详细信息

关键词： Global well-posedness Incompressible Navier-Stokes equations Slow variables

Flexural resonance vibrations of piezoelectric ceramic tubes in Besocke-style scanners

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Chinese Physics B 2012年第8期21卷 180-185页

作者：张辉张淑仪范理 Laboratory of Modern Acoustics Institute of AcousticsNanjing University

Flexural resonance vibrations of piezoelectric ceramic tubes in Besocke-style scanners with nanometer resolution are studied by using an electro-mechanical coupling Timoshenko beam model. Meanwhile, the effects of friction, the first moment, and moment of inertia induced by mass loads are considered. The predicted resonance frequencies of the ceramic tubes are sensitive to not only the mechanical parameters of the scanners, but also the friction acting on the attached shaking ball and corresponding bending moment on the tubes. The theoretical results are in excellent agreement with the related experimental measurements. This model and corresponding results are applicable for optimizing the structures and performances of the scanners.

关键词： flexural resonance vibration Timoshenko beam theory Besocke-style scanner

Impacts of channel morphology on residues and ecological risks of polychlorinated biphenyls in water and sediment in Chahe River

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Water Science and Engineering 2016年第4期9卷 300-311页

作者： Zhen-hua Zhao Jie Sun Xiao-kun Fang Li-ling Xia Javid Hussain Department of Plant Soil and Microbial Sciences Michigan State University East Lansing MI 48824 USA key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education Hohai University Nanjing 210098 China College of Environment Hohai University Nanjing 210098 China Nanjing Institute of Industry Technology Nanjing 210016 China

The impacts of channel morphology on the residues and ecological risks of 14 polychlorinated biphenyl(PCB) congeners in water and sediment were investigated in summer(July) and autumn(September) in the Chahe River,in Nanjing,*** residual concentrations of trichlorobiphenyls(tri-CBs,PCB 18) and tetra-CBs(PCB 52) in water were significantly higher than those of penta-CBs to deca-CBs,and the average residual concentration of ∑PCBs(sum of 14 PCB congeners) in summer was about six times higher than in ***,the residues in sediment did not change *** analysis(RDA) indicated that channel morphology and the corresponding environmental indices had significant impacts on PCB residues and their composition profiles in water and *** overflow weir and lake-type watercourse may remarkably reduce the residual concentration and ecological risks of PCBs in *** highest reduction percentages of the residual concentration and ecological risks of ∑PCBs induced by an overflow weir were 78%and 67%,respectively,and those induced by a lake-type watercourse were 36%and 70%,*** watercourses with different channel morphologies were ranked by residual ∑PCBs concentrations in the following descending order:the natural ecological watercourse,vertical concrete watercourse,and vegetation-type riprap ***,they were ranked by residual ∑PCBs concentrations in sediment in the following descending order:the vertical concrete watercourse,vegetation-type riprap watercourse,and natural ecological watercourse.

关键词： Channel morphology RDA Ecological risk Toxic equivalent concentration

Numerical investigation of the nonlinear spectral broadening aiming at a few-cycle regime for 10 ps level Nd-doped lasers

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Chinese Physics B 2022年第9期31卷 320-325页

作者： Xi-Hang Yang Fen-Xiang Wu Yi Xu Jia-Bing Hu Pei-Le Bai Hai-Dong Chen Xun Chen Yu-Xin Leng key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of sciences Beijing 100049China

We present a cascaded nonlinear spectral broadening scheme for Nd-doped lasers,featuring with long pulse duration and high average *** scheme is based on two multi-pass cells(MPCs)and one multiple-plate supercontinuum generation(MPSG),and the numerical investigation is driven by a home-made Nd-doped fiber laser with 12 ps pulse duration,50 kHz repetition rate and 100 W average *** MPC-based first two stages allow us to broaden the pulse spectrum to 4 nm and 43 nm respectively,and subsequently,the MPSG-based third stage allows us to reach 235 nm spectral *** broadened spectrum can support a Fourier-transfer-limited pulse duration of 9.8 fs,which is shorter than three optical *** the best of our knowledge,it is the first time to demonstrate the possibility of few-cycle pulses generation based on the 10 ps level Nd-doped *** few-cycle and high average power laser sources should be attractive and prospective,benefiting from the characteristics of structure compact,low-cost and flexibility.

关键词： nonlinear spectral broadening picosecond lasers high average power

A self-adaptive grey forecasting model and its application

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Journal of Systems Engineering and Electronics 2022年第3期33卷 665-673页

作者： TANG Xiaozhong XIE Naiming College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Industry and Finance Huangshan Vocational and Technical CollegeHuangshan 245000China

GM(1,1)models have been widely used in various fields due to their high performance in time series ***,some hypotheses of the existing GM(1,1)model family may reduce their prediction performance in some *** solve this problem,this paper proposes a self-adaptive GM(1,1)model,termed as SAGM(1,1)model,which aims to solve the defects of the existing GM(1,1)model family by deleting their modeling ***,a novel multi-parameter simultaneous optimization scheme based on firefly algorithm is proposed,the proposed multi-parameter optimization scheme adopts machine learning ideas,takes all adjustable parameters of SAGM(1,1)model as input variables,and trains it with firefly *** Sobol’sensitivity indices are applied to study global sensitivity of SAGM(1,1)model parameters,which provides an important reference for model parameter ***,forecasting capability of SAGM(1,1)model is illustrated by Anhui electricity consumption *** show that prediction accuracy of SAGM(1,1)model is significantly better than other models,and it is shown that the proposed approach enhances the prediction performance of GM(1,1)model significantly.

关键词： grey forecasting model GM(1,1)model firefly algo-rithm Sobol’sensitivity indices electricity consumption prediction