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12-Ring Network Coordination Polymer——{[Cu(C_4N_2H_(10))_4]_2·H_4V_4O_(14)}_n Formed by Linking cyclo-[H_4V_4O_(14)]^(4-) with Cu(C_4N_2H_(10))^(2+)_4 Cation Clusters

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Chemical Research in Chinese Universities 2006年第6期22卷 688-691页

作者： LI ya-feng ZHANG Li-mei WU Lei-lei WANG Sheng-hai WANG Hai-lian shang xuan-xuan College of Chemistry and Molecular Engineering College of Mathematics and Physics Qingdao University of Science ＆ Technology 266042 Qingdao P. R. China

A novel 12-ring network coordination polymer, { [ Cu （ C4 N2 H10 ） 4 ]2 H4 V4 O14 } n （ denoted as QUST-4）, was hydrothermally synthesized and structurally determined by X-ray single-crystal diffraction analysis. QUST-4 was crystallized in a monoelinic system with space group P21/n. The parameters of the unit cell are a = 1. 0497（2） nm, b = 1.6728（3） nm, c=1.2857（3） nm, 3=94. 14（3）°, V=2.2517（8） nm^3, Z=4, Dcal = 1.841 Mg/m^3, R1 = 0. 1071, and wR3 =0. 2703. The largest difference peak and hole were 2284 and - 1040 c/nm^3, respectively. The SBU（ secondary building unit） of QUST-4 was a new cyclo- aggregate of polyoxovanadate cyelo-[ S4V4O14 ]^4 - , different from cyclo-[ V4O12 ]^4-, which was condensed from two tetrahedral and two trigonal bipyramids via ahernate arrangement. Cu（piper） 4 （ piper = piperazine ） group connected the cyclo- [ H4 V4 O14 ] ^4 - anions to form the 12-ring network. The adjacent layers were linked by van der Walls forces.

关键词： Coordination polymer Aggregate of polyoxovanadate Hydrothermal synthesis Network

Burden of mental disorders and risk factors in the Western Pacific region from 1990 to 2021

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World Journal of Psychiatry 2025年第1期15卷 93-105页

作者： ya-Xin Xu Xiao-xuan Niu Wen-Chang Jia Jing Wen Xue-Lin Cheng yan Han Ming-Hui Peng Jing Zhou yao Liu Sun-Fang Jiang Xiao-Pan Li Department of Health Management Centre Zhongshan HospitalFudan UniversityShanghai 200030China Department of General Practice Zhongshan HospitalFudan UniversityShanghai 200030China Department of Nutrition Zhongshan HospitalFudan UniversityShanghai 200032China School of Public Health Fudan UniversityShanghai 200032China

BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and *** To analyze the burden of MD in the WPR from 1990 to 2021,along with associated risk factors,to reveal changing trends and emerging *** We used data from the Global Burden of Disease 2021,analyzing prevalence,incidence,and disability-adjusted life years(DALYs)of MD from 1990 to *** methods included age-standardisation and uncertainty analysis to address variations in population structure and data *** Between 1990 and 2021,the prevalence of MD rose from 174.40 million cases[95%uncertainty interval(UI):160.17-189.84]to 234.90 million cases(95%UI:219.04-252.50),with corresponding DALYs increasing from 22.8 million(95%UI:17.22-28.79)to 32.07 million(95%UI:24.50-40.68).During this period,the burden of MD shifted towards older age *** and anxiety disorders were predominant,with females showing higher DALYs for depressive and anxiety disorders,and males more affected by conduct disorders,attention-deficit hyperactivity disorder,and autism spectrum ***,New Zealand,and Malaysia reported the highest burdens,whereas Vietnam,China,and Brunei Darussalam reported the ***,childhood sexual abuse and bullying,and intimate partner violence emerged as significant risk *** This study highlights the significant burden of MD in the WPR,with variations by age,gender,and *** coronavirus disease 2019 pandemic has exacerbated the situation,emphasizing the need for a coordinated response.

关键词： Mental disorders Western pacific region Global Burden of Disease Risk factors Disability-adjusted life years

On Ding Projective Complexes

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维普期刊数据库

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Acta Mathematica Sinica,English Series 2018年第11期34卷 1718-1730页

作者： Gang yaNG xuan shang DA Department of Mathematics Lanzhou Jiaotong University

In the paper, Ding projective modules and Ding projective complexes are considered. In particular, it is proven that Ding projective complexes are precisely the complexes X for which each Xm is a Ding projective R-mod... 详细信息

关键词： Gorenstein projective modules Ding projective and Ding injective modules Ding projec-tive complexes

Supersymmetric Sawada-Kotera-Ramani Equation: Bilinear Approach

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Communications in Theoretical Physics 2008年第3期49卷 685-688页

作者： YU ya-xuan Department of Mathematics Ningbo University Ningbo 315211 China

In this paper, using the Hirota＇s bilineax method, we consider the N = 1 supersymmetric Sawada-Kotera- Ramani equation and obtain the Bazcklund transformation of it. Its one- and two-supersoliton solutions axe obtain... 详细信息

关键词： N = 1 supersymmetric Sawada-Kotera-Ramani equation Backlund transformation supersoliton solutions

New Compacton Solutions and Solitary Pattern Solutions for Modified Nonlinearly Dispersive mK(m,n,a,b) Equation

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Communications in Theoretical Physics 2009年第10期52卷 637-640页

作者： YU ya-xuan Department of Applied Mathematics Ningbo University Ningbo 315211 China

In this paper exact solutions of a new modified nonlinearly dispersive equation （simply called inK（m, n, a, b） Ua Ub equation）, u^m-1 ut ＋ α（ u^n）x ＋β（u^a（u^b）xx）x = 0, is investigated by using some direct algorithms. As a result, abundant new compacton solutions （solitons with the absence of infinite wings） and solitary pattern solutions （having infinite slopes or cusps） are obtained.

关键词： mK(m n a b) equation compacton solution solitary pattern solution

Modified scaling angular spectrum method for numerical simulation in long-distance propagation

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Chinese Physics B 2021年第3期30卷 266-274页

作者： Xiao-Yi Chen ya-xuan Duan Bin-Bin Xiang Ming Li Zheng-shang Da The Advanced Optical Instrument Research Department Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

The angular method(AS)cannot be used in long-distance propagation because it produces severe numerical errors due to the sampling problem in the transfer *** ways can solve this problem in AS for long-distance *** is zero-padding to make sure that the calculation window is wide enough,but it leads to a huge calculation *** other is a method called band-limited angular spectrum(BLAS),in which the transfer function is truncated and results in that the calculation accuracy decreases as the propagation distance *** this paper,a new method called modified scaling angular spectrum(MSAS)to solve the problem for long-distance propagation is proposed.A scaling factor is introduced in MSAS so that the sampling interval of the input plane can be adjusted arbitrarily unlike AS whose sampling interval is restricted by the detector’s pixel *** sampling interval of the input plane is larger than the detector’s pixel size so the size of calculation window suitable for long-distance field propagation in the input plane is smaller than the size of the calculation window required by the ***,the method reduces the calculation redundancy and improves the calculation *** results from simulations and experiments show that MSAS has a good signal-to-noise ratio(SNR),and the calculation accuracy of MSAS is better than BLAS.

关键词： angular spectrum diffraction Fourier optics and signal process

Broad-band phase retrieval method for transient radial shearing interference using chirp Z transform technique

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Chinese Physics B 2021年第8期30卷 398-406页

作者： Fang Xue ya-xuan Duan Xiao-Yi Chen Ming Li Suo-Chao Yuan Zheng-shang Da The Advanced Optical Instrument Research Department Xi'an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi'an 710119China University of Chinese Academy of Sciences Beijing 100049China

The transient radial shearing interferometry technique based on fast Fourier transform(FFT)provides a means for the measurement of the wavefront phase of transient light ***,which factors affect the spatial bandwidth of the wavefront phase measurement of this technology and how to achieve high-precision measurement of the broad-band transient wavefront phase are problems that need to be studied *** this end,a theoretical model of phase-retrieved bandwidth of radial shearing interferometry is established in this *** influence of the spatial carrier frequency and the calculation window on phase-retrieved bandwidth is analyzed,and the optimal carrier frequency and calculation window are *** this basis,a broad-band transient radial shearing interference phase-retrieval method based on chirp Z transform(CZT)is proposed,and the corresponding algorithm is *** theoretical simulation,a known phase is used to generate the interferogram and it is retrieved by the traditional method and the proposed method *** residual wavefront RMS of the traditional method is 0.146λ,and it is 0.037λfor the proposed method,which manifests an improvement of accuracy by an order of *** the same time,different levels of signal-to-noise ratios(SNRs)from 50 dB to 10 dB of the interferogram are simulated,and the RMS of the residual wavefront is from 0.040λto 0.066λ.In terms of experiments,an experimental verification device based on a phase-only spatial light modulator is built,and the known phase on the modulator is retrieved from the actual *** RMS of the residual wavefront retrieved through FFT is 0.112λ,and it decreases to 0.035λthrough *** experimental results verify the effectiveness of the method proposed in this ***,the method can be used in other types of spatial carrier frequency interference,such as lateral shearing interference,rotational shearing interference,flipping shearing interference,and

关键词： radial shearing interference chirp Z transform(CZT) phase retrieval

Research on new type of fast-opening mechanism in steam turbine regulating system and optimization of operation tactic

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第5期9卷 633-639页

作者： Xiao-xiao LI xuan-yin WANG Fu-shang LI The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Shandong Electrical Power Institute Jinan 250002 China

With the analysis on regulating system in 200 MW steam turbine, the necessity of appending the fast-opening function to the original system is set forth and a new type of fast-opening mechanism is devised. The mathematical model of system is built up. With the use of AMESIM software, the displacement curve of the piston, the force curve of the cartridge valve spool, the pressure curve and the flux curve in the regulation process are obtained based on simulation. The performances of three fast-opening systems composed of cartridge valves with different diameters are compared. Based on the analysis on factors that affect the execution time of fast-opening, the dead zone of the fast-opening system is put forward. To overcome the defect, dif- ferent operation modes are adopted for different zones. The result shows that with the increase of the valve diameter, the regulating time in the dead zone significantly exceeds the fast-opening time in the whole journey. Accordingly, the optimization operation tactic in the dead zone and the qualification conditions are brought forward. The fast-opening system composed of 32 mm cartridge valves is taken as an example with use of the tactic. The simulation result shows that the maximum regulating time is shortened by 509 ms.

关键词： Steam turbine Fast-opening Regulating system AMESIM

In situ TiN-reinforced CoCr2FeNiTi(0.5) high-entropy alloy composite coating fabricated by laser cladding

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Rare Metals 2020年第10期39卷 1190-1195页

作者： ya-Xiong Guo Qi-Bin Liu Xiao-Juan shang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Materials Structure and Strength Guiyang 550025China

The fcc structural CoCr2 FeNiTi(0.5) high-entropy alloy(HEA) composite coating with TiN particles reinforced was acquired by laser cladding on the commercial904 L stainless *** results show that phase structure is mainly composed of fcc solid solution and TiN *** coating exhibits excellent structural stability below850℃.The microstructure consists of irregular dendrite and TiN *** electron microscopy(TEM) results reveal that the close-packed plane of fcc phase is(111) with interplanar spacing of ~ 0.208 *** interface between TiN and fcc matrix is *** the angle of boundary between dendrite and matrix is ~ 65°.The hardness and corrosion resistance of coating have much improvement compared with those of substrate.

关键词： TiN particle reinforced High-entropy alloy Semi-coherent interface Laser cladding