检索结果-南通市图书馆

Frontiers of Chemical Science and Engineering 2024年第5期18卷 95-103页

作者： Jianxia Gu Ying Zhu Haiyan Zheng Chunyi Sun Zhongmin Su department of Chemistry Xinzhou Normal UniversityXinzhou 034000China School of Chemistry Northeast Normal UniversityChangchun 130024China

A novel,cheap and highly efficient Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen *** in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions,which avoids the aggregation of catalyst particles during the pyrolysis *** optimization,the obtained Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C possesses small size(3-8 nm),large specific surface area and hierarchical pore *** importantly,Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L^(-1)H_(2)SO_(4)(102.3 mV)and 1 mol·L^(-1)KOH(95 mV)to afford the current density of 10 mA·cm^(-2),as well as small Tafel slopes of 82.49 and 99.92 mV·dec^(-1),***,this catalyst also shows outstanding stability for 12 h without a significant change in current *** excellent catalytic performance of Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C can put down to the synergistic effect between multiple components and the small size of the *** work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.

关键词： polyoxometallates layered double hydroxide transition metal-based electrocatalysts hydrogen evolution reaction

Generic singularities for 2D pressureless flows

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china mathematics 2024年

作者： Alberto Bressan Geng Chen Shoujun Huang department of mathematics Penn State University University Park department of mathematics University of Kansas College of Mathematical Medicine Zhejiang Normal University

In this paper, we consider the Cauchy problem for pressureless gases in two space dimensions with the generic smooth initial data(density and velocity). These equations give rise to singular curves, where the mass has a positive density with respect to the 1-dimensional Hausdorff measure. We observe that the system of equations describing these singular curves is not hyperbolic. For analytic data, local solutions are constructed by using a version of the Cauchy-Kovalevskaya theorem. We then study the interaction of two singular curves in the generic position. Finally, for a generic initial velocity field, we investigate the asymptotic structure of the smooth solution up to the first time when a singularity is formed.

关键词：

Global Phase Portraits of Uniform Isochronous Centers System of Degree Six with Polynomial Commutator

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第3期40卷 577-599页

作者： Li-na GUO Ai-yong CHEN Shuai-feng ZHAO School of mathematics and Statistics Henan University of Science and TechnologyLuoyang 471023China department of mathematics Hunan First Normal UniversityChangsha 410205China School of Mechatronics Engineering Henan University of Science and TechnologyLuoyang 471023China

This paper studies the global phase portraits of uniform isochronous centers system of degree six with polynomial *** systems have the form x=-y+xf(x,y),y=x+yf(x,y),where f(x,y)=a_(1)x+a_(2)xy+a_(3)xy^(2)+a_(4)xy^(3)+a_(5)xy^(4)=xσ(y),and any zero of 1+a_(1)y+a_(2)y^(2)+a_(3)y^(3)+a_(4)y^(4)+a_(5)y^(5),y=y is an invariant straight *** last,all global phase portraits are drawn on the Poincare disk.

关键词： global phase portraits uniform isochronous center polynomial commutator invariant straight lines

维普期刊数据库

Influence of nonalcoholic fatty liver disease on response to antiviral treatment in patients with chronic hepatitis B:A meta-analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Hepatology 2024年第3期16卷 465-476页

作者： Shi-Yi Liu Dian Wang Jing Liu Lu-Ping Yang Gong-Ying Chen department of Medicine Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina department of Medicine Hangzhou Normal UniversityHangzhou 310011Zhejiang ProvinceChina department of Infectious and Hepatology Diseases Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015Zhejiang ProvinceChina

BACKGROUND Although hepatitis B virus infection is the leading cause of chronic liver injury globally,nonalcoholic fatty liver disease(NAFLD)is gradually gaining attention as another major chronic liver *** number of patients having chronic hepatitis B(CHB)with concomitant hepatic steatosis has *** To analyze the effect of NAFLD on the response to antiviral treatment in patients with *** Relevant English studies were systematically searched across PubMed,EMBASE,Web of Science,and Cochrane Library until October *** in which the treatment outcomes were compared between patients with CHB only and those with CHB and hepatic steatosis were *** Of the 2502 retrieved studies,11 articles were finally *** response until 48 wk(OR=0.87,95%CI:0.50–1.53,P=0.000)and 96 wk(OR=0.35,95%CI:0.24–0.53,P=0.24)and virological response until 96 wk(OR=0.80,95%CI:0.43–1.49,P=0.097)were lower in patients with hepatic steatosis than in patients with CHB *** Hepatic steatosis lowers the biochemical response to antiviral treatment in patients with CHB.

关键词： Nonalcoholic fatty liver disease Hepatitis B virus Antiviral treatment effect Meta-analysis

Room-temperature nitrogen-rich niobium nitride photodetector for terahertz detection

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optoelectronics Letters 2024年第11期20卷 641-646页

作者： LU Xuehui LIU Binding CHI Chengzhu LIU Feng SHI Wangzhou department of Physics Mathematics & Science College Shanghai Normal University

A sensitive room-temperature metal-semiconductor-metal(MSM) structure is fabricated on high-resistivity silicon substrates(ρ>4 000 Ω·cm) for terahertz(THz) detection by utilizing the photoconductive effect.

关键词： A

ON THE UNIVALENCE OF CERTAIN POLYHARMONIC MAPPINGS WITH BOUNDED LENGTH DISTORTIONS

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第6期44卷 2125-2138页

作者：汪欣 Saminathan PONNUSAMY 刘名生 department of mathematics Shenzhen Polytechnic University department of mathematics Indian Institute of Technology Madras School of Mathematical Sciences South China Normal University

The main purpose of this paper is to investigate the univalence of normalized polyharmonic mappings with bounded length distortions in the unit *** first establish the coefficient estimates for polyharmonic mappings with bounded length ***,using these results,we establish five Landau-type theorems for subclasses of polyharmonic mappings F and L(F), where F has bounded length distortion and L is a differential operator.

关键词： biharmonic mappings coefficients estimates harmonic mappings Landau-type theorems polyharmonic mappings

Hausdorff Measure of Space Anisotropic Gaussian Processes with Non-stationary Increments

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年

作者： Jun WANG Zhen-long CHEN Wei-jie YUAN Guang-jun SHEN School of mathematics and Physics Anhui Polytechnic University School of Statistics and mathematics Zhejiang Gongshang University department of mathematics Anhui Normal University

Let X={X(t), t∈R+}be a centered space anisotropic Gaussian process values in Rdwith non-stationary increments, whose components are independent but may not be identically distributed. Under certain conditions, then almost surely c1≤?-m(X([0, 1]))≤c2, where ? denotes the exact Hausdorff measure associated with function ?(s)=s(1/αk+∑i=1k(1-αi/αk)) log log 1/s for some 1≤k≤d,(α1,···, αd)∈(0, 1]d. We also obtain the exact Hausdorff measure of the graph of X on [0, 1].

关键词：

Curvature-enhanced multipartite coherence in the multiverse

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第7期48卷 259-272页

作者：吴树民王春旭王锐迪李金璇黄晓理曾浩生 department of Physics Liaoning Normal UniversityDalian 116029China department of Physics Hunan Normal UniversityChangsha 410081China

Here,we study the quantum coherence of N-partite Greenberger-Horne-Zeilinger(GHZ)and W states in the multiverse consisting of N causally disconnected de Sitter ***,N-partite coherence increases monotonically with curvature,whereas the curvature effect destroys quantum entanglement and discord,indicating that the curvature effect is beneficial to quantum coherence and harmful to quantum correlations in the *** find that with an increase in n expanding de Sitter spaces,the N-partite coherence of the GHZ state increases monotonically for any curvature,whereas the quantum coherence of the W state decreases or increases monotonically depending on the *** find a distribution relationship,which indicates that the correlated coherence of the N-partite W state is equal to the sum of all bipartite correlated coherence in the *** coherence exhibits unique properties in the multiverse,suggesting that it may provide some evidence for the existence of the multiverse.

关键词： multiverse curvature effect multipartite coherence

维普期刊数据库

The qqsQ(q=u,d;Q=c,b)tetraquark system in a chiral quark model

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第7期48卷 84-105页

作者：杨刚平加伦 Jorge Segovia department of Physics Zhejiang Normal UniversityJinhua 321004China department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China Departamento de Sistemas Físicos Químicos y NaturalesUniversidad Pablo de OlavideE-41013 SevillaSpain

The S-wave qqsQ(q=u,d;Q=c,b)tetraquarks,with spin-paritiesJ^(P)=0^(+),1^(+),and 2^(+),in both isoscalar and isovector sectors,are systematically studied using a chiral quark *** meson-meson,diquark-antidiquark,and K-type arrangements of quarks and all possible color wave functions are comprehensively *** four-body system is solved using the Gaussian expansion method,a highly efficient computational ***,a complex-scaling formulation of the problem is established to disentangle bound,resonance,and scattering *** theoretical framework has already been successfully applied in various tetra-and penta-quark *** the complete coupled channel and within the complex-range formulation,several narrow resonances of qqsC and qqsb systems are obtained,in each allowed I(J^(P))-channel,within the energy regions of 2.4-3.4 GeV and 5.7-6.7GeV,*** predicted exotic states,which indicate a richer color structure when going towards multiquark systems beyond mesons and baryons,are expected to be confirmed in future high-energy particle and nuclear experiments.

关键词： quantum chromodynamics quark models

GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第4期44卷 1301-1326页

作者： Xuejun ZHANG Yuting GUO Hongxin CHEN Pengcheng TANG College of mathematics and Statistics Hunan Normal University.Changsha 410081China School of mathematics Hunan UniversityChangsha 410082China School of mathematics and Computational Science Hunan University of Science and TechnologyXiangtan 411201China

In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type *** order to prov... 详细信息

关键词： Forelli-Rudin type operator L^(p,q,s,k)(B_(n))space boundedness unit ball

维普期刊数据库