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Chinese Chemical Letters 2023年第10期34卷 102-105页

作者： Pengyuan qiu Yan An Xinyu Wang Shanna An Xiaoli Zhang jian Tian Wen zhu School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

As one of the 2D transition metal sulfides,1T phase MoS_(2) nanosheets(NSs)have been studied because of their distinguished conductivity and suitable electronic ***,the active sites are limited to a small number of edge sites only,while the basal plane is catalytically ***,we report that boron(B)doped 1T phase MoS_(2) NSs can replace precious metals as a co-catalyst to assist in photocatalytic H_(2) production of 2D layered g-C_(3)N_(4) nanosheets(g-C_(3)N_(4) NSs).The H_(2) evolution rate of prepared B-MoS_(2)@g-C_(3)N_(4) composites with 15 wt%B-MoS_(2)(B-MoS_(2)@g-C_(3)N_(4)–15,1612.75μmol h^(−1) g^(−1))is 52.33 times of pure g-C_(3)N_(4) NSs(30.82μmol h^(−1) g^(−1)).Furthermore,the apparent quantum efficiency(AQE)of B-MoS_(2)@g-C_(3)N_(4)–15 composites under the light atλ=370 nm is calculated and reaches 5.54%.The excellent photocatalytic performance of B-MoS_(2)@g-C_(3)N_(4)–15 composites is attributed to the B ions doping inducing the distortion of 1T phase MoS_(2) crystal,which can activate more base planes to offer more active sites for H_(2) evolution reaction(HER).This work of B-MoS_(2)@g-C_(3)N_(4) composites offers experience in the progress of effective and low-price photocatalysts for HER.

关键词： 1T phase MoS_(2) g-C_(3)N_(4)nanosheets Photocatalytic H_(2)evolution Active sites Boron doping

Recent Progress of Graphene Fiber/Fabric Supercapacitors:From Building Block Architecture,Fiber Assembly,and Fabric Construction to Wearable Applications

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Advanced Fiber Materials 2023年第3期5卷 896-927页

作者： Tuxiang Guan Zemei Li Dianchun qiu Guan Wu jian Wu Liping zhu Meifang zhu Ningzhong Bao State Key Laboratory of Materials‑Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009People’s Republic of China National Engineering Lab for Textile Fiber Materials and Processing Technology School of Materials Science and EngineeringZhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620People’s Republic of China

High-performance fiber-shaped power sources are anticipated to considerably contribute to the continuous development of smart wearable *** one-/two-dimensional(1D/2D)frameworks constructed from graphene sheets,graphene fibers and fabrics inherit the merits of graphene,including its lightweight nature,high electrical conductivity,and exceptional mechanical *** as-fabricated graphene fiber/fabric flexible supercapacitor(FSC)is,therefore,regarded as a promis-ing candidate for next-generation wearable energy storage devices owing to its high energy/power density,adequate safety,satisfactory flexibility,and extended cycle *** gap between practical applications and experimental demonstrations of FSC is drastically reduced as a result of technological *** this end,herein,recent advancements of FSCs in fiber element regulation,fiber/fabric construction,and practical applications are methodically reviewed and a forecast of their growth is presented.

关键词： Graphene fibers/fabrics Flexible supercapacitor Element regulation Fiber/fabric construction Wearable application

Ricci-Bourguignon Flow on Manifolds with Boundary

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Chinese Annals of Mathematics,Series B 2021年第6期42卷 953-968页

作者： Hongbing qiu Anqiang zhu School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Computational Science Wuhan UniversityWuhan430072China Corresponding author.School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

The authors consider the short time existence for Ricci-Bourguignon flow on manifolds with *** the initial metric has constant mean curvature and satisfies some compatibility conditions,they show the short time existe... 详细信息

关键词： Ricci-Bourguignon flow Boundary value problem

Stochastic optimal control of cable vibration in plane by using axial support motion

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Acta Mechanica Sinica 2011年第4期27卷 578-586页

作者： Ming Zhao Wei-qiu zhu Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University 310027 Hangzhou China

A stochastic optimal control strategy for a slightly sagged cable using support motion in the cable axial direction is proposed. The nonlinear equation of cable motion in plane is derived and reduced to the equations for the first two modes of cable vibration by using the Galerkin method. The partially averaged Ito equation for controlled system energy is further derived by applying the stochastic averaging method for quasi-non-integrable Hamiltonian systems. The dynamical programming equation for the controlled system energy with a performance index is established by applying the stochastic dynamical programming principle and a stochastic optimal control law is obtained through solving the dynamical programming equation. A bilinear controller by using the direct method of Lyapunov is introduced. The comparison between the two controllers shows that the proposed stochastic optimal control strategy is superior to the bilinear control strategy in terms of higher control effectiveness and efficiency.

关键词： Stay cable Active control - Stochastic optimalcontrol Dynamical programming principle

A symplectic finite element method based on Galerkin discretization for solving linear systems

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1305-1316页

作者： Zhiping qiu Zhao WANG Bo zhu Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100083China

We propose a novel symplectic finite element method to solve the structural dynamic responses of linear elastic *** the dynamic responses of continuous medium structures,the traditional numerical algorithm is the dissipative algorithm and cannot maintain long-term energy ***,a symplectic finite element method with energy conservation is constructed in this paper.A linear elastic system can be discretized into multiple elements,and a Hamiltonian system of each element can be *** single element is discretized by the Galerkin method,and then the Hamiltonian system is constructed into the Birkhoffian ***,all the elements are combined to obtain the vibration equation of the continuous system and solved by the symplectic difference *** the numerical experiments of the vibration response of the Bernoulli-Euler beam and composite plate,it is found that the vibration response solution and energy obtained with the algorithm are superior to those of the Runge-Kutta *** results show that the symplectic finite element method can keep energy conservation for a long time and has higher stability in solving the dynamic responses of linear elastic systems.

关键词： Galerkin finite element method linear system structural dynamic response symplectic difference scheme

Relationship between somatostatin receptor subtype expression and clinicopathology,Ki-67,Bcl-2 and p53 in colorectal cancer

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World Journal of Gastroenterology 2006年第13期12卷 2011-2015页

作者： Cheng-Zhi qiu Chuan Wang Zhong-Xin Huang Shi-Ze zhu You-Yi Wu jian-Long qiu Department of General Surgery Second Affiliated Hospital of Fujian Medical University Quanzhou 362000 Fujian Province China Department of Oncology Affiliated Union Hospital to Fujian Medical University Fuzhou 350001 Fujian Province China Department of Pathology Second Affiliated Hospital of Fujian Medical University Quanzhou 362000 Fujian Province China

AIM： To study the SSTR1, 2, 3, 4, 5 expression and their relationships with clinico-pathological factors, cell proliferation, Bcl-2 and p53 expression in colorectal cancer cells. METHODS： Immunohistochemical staining of five SSTR subtypes, Ki-67, Bcl-2 and p53 was performed by the standard streptavidin-peroxidase （SP） technique for the paraffin sections of 127 colorectal cancers, and expression of five SSTR subtypes in 40 specimens of normal colorectal mucosae was detected with the same method. RESULTS： Positive staining for five SSTR subtypes was observed in colorectal cancer cells and normal colorectal mucosae. SSTR1 was the most predominant subtype in both colorectal cancer and normal colorectal mucosa, and the second was SSTR5 or SSTR2. As compared with normal colorectal mucosa, SSTR4 was more frequently expressed in colorectal cancer cells （2.5% vs 18.9%, P〈 0.05）; the expression of SSTR2, 4, 5 in moderately to well differentiated colorectal adenocarcinoma was significantly higher than that in poorly differentiated ones （P〈 0.05）, the SSTR1 expression in colorectal cancer with positive lymph node metastasis was significantly higher than that with negative lymph node metastasis （72.2% and 54.5%, P〈 0.05）. In addition, in the ulcerative type of colorectal cancer, SSTR2 expression was obviously decreased （P 〈 0.05）; the correlation did not reach a statistical significance between the five SSTR subtypes expression and Dukes＇stages （P〉 0.05）, but the frequency of SSTR1 expression increased with Dukes＇ stage, while SSTR3 and SSTR5 expression decreased with Dukes＇ stage. Moreover, there was no correlation between expression of the five SSTR subtypes and other clinicopathological factors such as age, sex, tumor site, tumor depth, distant metastasis. The proliferative indexes in colorectal cancer cells with negative expression of SSTR2 and SSTR3 were significantly higher than that with positive expression （P〈0.05）. The Bcl-2 expression in colorectal cancer cells with po

关键词： Somatostatin receptor subtype Cell proliferation Apoptosis, p53, Colorectal cancer Immunohistochemistry

A micro-chip exploding foil initiator based on printed circuit board technology

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Defence Technology（防务技术） 2022年第8期18卷 1435-1444页

作者： Zhi Yang Peng zhu Qing-yun Chu qiu Zhang Ke Wang Hao-tian jian Rui-qi Shen School of Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Micro-Nano Energetic Devices Key Laboratory Ministry of Industry and Information TechnologyNanjing210094China

Conventional exploding foil initiator (EFI) in ignition or detonation applications hosts many performance advantages, but was hindered by the bulky, inaccurate, inefficient and expensive shortcomings. We highlight a novel micro-chip exploding foil initiator (McEFI) using printed circuit board (PCB) technology. The structural parameters were determined based on energy coupling relationship at the component interfaces. Next, the prototype McEFI has been batch-fabricated using PCB technology, with a monolithic structure of 7.0 mm (l) × 4.5 mm (w) × 4.0 mm (δ). As expected, this PCB-McEFI illustrated the successful firing validations for explosives pellets. This paper has addressed the cost problem in both military munitions and civil markets wherever reliable, insensitive and timing-dependent ignition or detonation are involved.

关键词： Exploding foil initiator Printed circuit board Monolithic structure Firing validations

Internal structural optimization of hollow fan blade based on sequential quadratic programming algorithm

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航空动力学报 2011年第4期26卷 787-793页

作者： YANG jian-qiu WANG Yan-rong School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

Several structural design parameters for the description of the geometric features of a hollow fan blade were determined.A structural design optimization model of a hollow fan blade which based on the strength constraint and minimum mass was established based on the finite element method through these ***,the sequential quadratic programming algorithm was employed to search the optimal *** groups of value for initial design variables were chosen,for the purpose of not only finding much more local optimal results but also analyzing which discipline that the variables according to could be benefit for the convergence and *** surface method and Monte Carlo simulations were used to analyze whether the objective function and constraint function are sensitive to the variation of variables or *** the robust results could be found among a group of different local optimal solutions.

关键词： hollow fan blade structural optimization sequential quadratic algorithm finite element method Monte Carlo simulations

Automated Kinematics Measurement and Aerodynamics of a Bioinspired Flapping Rotary Wing

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Journal of Bionic Engineering 2017年第4期14卷 726-737页

作者： jianghao Wu jian qiu Yanlai Zhang School of Transportation Science and Engineering Beihang University Beijing 1 O0191 China

A physical model for a micro air vehicle with Flapping Rotary Wings （FRW） is investigated by measuring the wing kine- matics in trim conditions and computing the corresponding aerodynamic force using computational fluid dynamics. In order to capture the motion image and reconstruct the positions and orientations of the wing, the photogrammetric method is adopted and a method for automated recognition of the marked points is developed. The characteristics of the realistic wing kinematics are presented. The results show that the non-dimensional rotating speed is a linear function of non-dimensional flapping frequency regardless of the initial angles of attack. Moreover, the effects of wing kinematics on aerodynamic force production and the underlying mechanism are analyzed. The results show that the wing passive pitching caused by elastic deformation can sig- nificantly enhance lift production. The Strouhal number of the FRW is much higher than that of general flapping wings, indi- cating the stronger unsteadiness of flows in FRW.

关键词： bioinspired flapping rotary wing aerodynamics wing kinematics measurement computational fluid dynamics micro air vehicle

Predicting TBM penetration rate in hard rock condition:A comparative study among six XGB-based metaheuristic techniques

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Geoscience Frontiers 2021年第3期12卷 201-213页

作者： jian Zhou Yingui qiu Danial Jahed Armaghani Wengang Zhang Chuanqi Li Shuangli zhu Reza Tarinejad School of Resources and Safety Engineering Central South UniversityChangsha 410083China Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam School of Civil Engineering Chongqing UniversityChongqing 400045China Faculty of Civil Engineering University of Tabriz29 Bahman Blvd51666 TabrizIran

A reliable and accurate prediction of the tunnel boring machine(TBM)performance can assist in minimizing the relevant risks of high capital costs and in scheduling tunneling *** research aims to develop six hybrid models of extreme gradient boosting(XGB)which are optimized by gray wolf optimization(GWO),particle swarm optimization(PSO),social spider optimization(SSO),sine cosine algorithm(SCA),multi verse optimization(MVO)and moth flame optimization(MFO),for estimation of the TBM penetration rate(PR).To do this,a comprehensive database with 1286 data samples was established where seven parameters including the rock quality designation,the rock mass rating,Brazilian tensile strength(BTS),rock mass weathering,the uniaxial compressive strength(UCS),revolution per minute and trust force per cutter(TFC),were set as inputs and TBM PR was selected as model *** with the mentioned six hybrid models,four single models i.e.,artificial neural network,random forest regression,XGB and support vector regression were also built to estimate TBM PR for comparison *** models were designed conducting several parametric studies on their most important parameters and then,their performance capacities were assessed through the use of root mean square error,coefficient of determination,mean absolute percentage error,and *** of this study confirmed that the best predictive model of PR goes to the PSO-XGB technique with system error of(0.1453,and 0.1325),R^(2) of(0.951,and 0.951),mean absolute percentage error(4.0689,and 3.8115),and a10-index of(0.9348,and 0.9496)in training and testing phases,*** developed hybrid PSO-XGB can be introduced as an accurate,powerful and applicable technique in the field of TBM performance *** conducting sensitivity analysis,it was found that UCS,BTS and TFC have the deepest impacts on the TBM PR.

关键词： TBM penetration rate Hard rock XGB-based hybrid model Predictive model Metaheuristic optimization