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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 567-586页

作者： zhiwei zhou Meixia CHEN Kun XIE School of Naval Architecture and Ocean Engineering Huazhong University of Science and Technology College of Engineering Huazhong Agricultural University

The free vibration of axially functionally graded(FG) tapered Timoshenko curved beams is studied with the numerical approach. By using the non-uniform rational B-spline(NURBS) basis functions, the exact geometry and the generalized displacement?eld are formulated. Variable geometric parameters and material properties, including the curvature, cross-sectional area, area moment of inertia, mass density, and Young’s modulus, are expanded as functions of the coordinate in a parametric domain. Based on Hamilton’s principle, the weak formulation is derived by applying a re?ned constitutive relation which considers the thickness e?ect. Natural frequencies and mode shapes are obtained from the eigenvalue equation. Circular, elliptic, and parabolic curved beams are considered in numerical examples. The obtained results are in good agreement with those in the existing studies and those calculated by the ?nite element software ***, the e?ects of the material gradient, taper ratio, slenderness ratio, and heightspan ratio on vibration behaviors are discussed.

关键词： free vibration functionally graded(FG) material non-uniform crosssection curved beam variable curvature thickness effect

Comprehensive treatment of a functional pancreatic neuroendocrine tumor with multifocal liver metastases

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Chinese Journal of Cancer Research 2014年第4期26卷 501-506页

作者： Wei Wang Sharvesh Raj Seeruttun Cheng Fang zhiwei zhou Department of Gastric and Pancreatic Surgery Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer Medicine

A 64-year-old man was admitted to the Sun Yat-Sen University Cancer Center with chief complaints of recurrent abdominal pain and diarrhea for about 3 years and with a history of surgical repair for intestinal perforation owing to stress ulcer. Positron emission tomography （PET）/computed tomography （CT） demonstrated a primary tumor on the pancreatic tail with multifocal liver metastases. Pathological and immunohistochemistry staining revealed the lesion to be a pancreatic neuroendocrine tumor （pNET）. According to the latest World Health Organization （WHO, 2013） classification, the tumor was classified as stage IV fimctional G1 pNET. After referral to the multidisciplinary treatment board （MDT）, the patient was started on periodic dose of omeprazole, somatostatin analogues and Interferon α （IFNα） and had scanning follow-ups. Based upon the imaging results, CT-guided radioactive iodine-125 （1251） seeds implantation therapy, radiofrequency ablation therapy （RFA） or microwave ablation technique were chosen for the treatment of the primary tumor. Transarterial chemoembolization （TACE）, RFA and microwave ablation techniques were decided upon for liver metastases. The patient showed beneficial response to the treatment with clinically manageable low-grade side effects and attained partial remission （RECIST criteria） with a good quality of life.

关键词： Pancreatic neuroendocrine tumor (pNET) functional liver metastases multidisciplinary team prognosis

Potential of Multi‑temporal InSAR for Detecting Retrogressive Thaw Slumps: A Case of the Beiluhe Region of the Tibetan Plateau

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International Journal of Disaster Risk Science 2023年第4期14卷 523-538页

作者： Zhiping Jiao Zhida Xu Rui Guo zhiwei zhou Liming Jiang State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China University of Chinese Academy of Sciences Beijing 100049China

Permafrost degradation due to climate warming is severely reducing slope stability by increasing soil pore water pressure and decreasing shear *** thaw slumps(RTSs)are among the most dynamic landforms in permafrost areas,which can result in the instability of landscape and ***,the spatiotemporal characteristics of surface deformation of RTSs are still unclear,and the potentials of deformation properties in mapping large-scale RTSs need to be further *** this study,we applied a multi-temporal Interferometric Synthetic Aperture Radar(MT-InSAR)method to map the spatiotemporal variations in surface deformation of RTSs in the Beiluhe region of the Tibetan Plateau by using 112 scenes of Sentinel-1 SAR data acquired from 2017 to *** deformation rates of RTSs ranged from−35 to 20 mm/year,and three typical motion stages were inferred by analyzing the deformation variation trend of the headwall of RTSs:stable,abrupt thaw,and linear subsidence.A total of 375 RTSs were identifed in the Mati Hill region by combining InSAR-based deformation results with visual interpretation of optical remote sensing *** them,76 RTSs were newly developed,and 26%more than the inventory derived from the optical images *** study demonstrated that the combination of InSAR-derived deformation with optical images has signifcant potential for detecting RTSs with high accuracy and efciency at the regional scale.

关键词： Multi-temporal InSAR Permafrost thawing Qinghai-Tibet Plateau(QTP) Retrogressive thaw slump

Optimized photocatalytic regeneration of adsorption-photocatalysis bifunctional composite saturated with Methyl Orange

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Journal of Environmental Sciences 2020年第8期32卷 40-51页

作者： Yi Shang Xing Li Yanling Yang Nan Wang Xiaoxuan Zhuang zhiwei zhou College of Architecture and Civil engineering Beijing University of TechnologyBeijing 100124China

Photo-responsive adsorption-photocatalysis nanocomposites are generally used in water and wastewater decontamination;however,the prolonged adsorption capacity of composites and the role of adsorption in concomitant photocatalysis are typically *** composites can be regenerated under light irradiation as their adsorption capacity ***,a novel adsorption-photocatalysis bifunctional nanocomposite,Bi-doped TiO2 supported on powdered activated carbon(Bi2O3/TiO2/PAC),was prepared using the solimpregnation-hydrothermal ***2O3/TiO2/PAC with a secondary calcination temperature of 700℃under a nitrogen atmosphere was selected for maximum adsorption capacity on Methyl Orange(MO).The composite displayed an excellent adsorption capacity and was easily separated and *** results demonstrate that 71.2%photocatalytic regeneration efficiency could be attained under visible light irradiation for 1 hr at an intensity of 750 W/m^2 and pH *** of the as-prepared Bi2O3/TiO2/PAC nanocomposite(700℃)indicates that it possesses a highly specific surface area and great optical properties,showing bifunctional adsorption-photocatalysis *** p-n heterojunction of the composite played a dominant role in the photocatalytic regeneration process,and effective degradation of MO could be achieved along with composite regeneration.

关键词： Photocatalytic regeneration Nanocomposite Powdered activated carbon Adsorption Photocatalysis

Coagulation efficiency and flocs characteristics of recycling sludge during treatment of low temperature and micro-polluted water

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Journal of Environmental Sciences 2012年第6期24卷 1014-1020页

作者： zhiwei zhou Yanling Yang Xing Li Wei Gao Heng Liang Guibai Li College of Architecture and Civil Engineering Beijing University of TechnologyBeijing 100124China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 15.0090China

Drinking water treatment sludge,characterized as accumulated suspended solids and organic and inorganic matter,is produced in large quantities during the coagulation *** proper disposal,regeneration or reuse of sludge is,therefore,a significant environmental *** sludge at low temperatures is an alternative method to enhance traditional coagulation *** the present study,the recycling mass of mixed sludge and properties of raw water （such as pH and turbidity） were systematically investigated to optimize coagulation *** determined that the appropriate dosage of mixed sludge was 60 mL/L,effective initial turbidity ranges were below 45.0 NTU,and optimal pH for DOMs and turbidity removal was 6.5-7.0 and 8.0,***,by comparing the flocs characteristics with and without recycling sludge,we found that floc structures with sludge were more irregular with average size growth to 64.7 μm from 48.1 μ*** sludge was a feasible and successful method for enhancing pollutants removal,and the more irregular flocs structure after recycling might be caused by breakage of reused flocs and incorporation of powdered activated carbon into larger flocs *** during the coagulation process,recycling sludge could be significant for the treatment of low temperature and micro-polluted source water.

关键词： recycling sludge sweep flocculation adsorption flocs characteristics

Suppress voltage decay of lithium-rich materials by coating layers with different crystalline states

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Journal of Energy Chemistry 2021年第9期30卷 591-598页

作者： zhiwei zhou Ziyan Luo Zhenjiang He Junchao Zheng Yunjiao Li Cheng Yan Jing Mao School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals Central South UniversityChangsha 410083HunanChina Engineering Research Center of the Ministry of Education for Advanced Battery Materials Central South UniversityChangsha 410083HunanChina School of Mechanical Medical and Process EngineeringScience and Engineering FacultyQueensland University of Technology(QUT)BrisbaneQueensland4001Australia School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina

Li-rich oxides are considered as the most commercial potential cathode materials due to the high theoretical specific discharge capacity. Here, ZrO_(2) in different crystalline states are applied as the coating layers to enhance the electrochemical performance of hollow Li[Li_(0.2)Mn_(0.54)Ni_(0.13)Co_(0.13)]O_(2) ***, a series of characterizations(XRD, SEM, TEM, EDX etc.) are conducted to compare the effects of ZrO_(2) coating layer with different crystalline states on the host material. The results elucidate that the Li-rich Mn-based material with the polycrystal ZrO_(2) coating layer has a slight advantage in rate performance, while the host material with the single crystal ZrO_(2)-coating layer has a better cycling performance and effectively suppresses voltage decay with the effect of excellently inhibiting layered to spinel-like phase transition and metal dissolution during charging and discharging process.

关键词： Lithium-ion battery Cathode material Surface modification Electrochemical performance Voltage decay

Catalytic degradation of chlorinated volatile organic compounds(CVOCs)over Ce-Mn-Ti composite oxide catalysts

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Journal of Environmental Sciences 2024年第4期138卷 326-338页

作者： zhiwei zhou Qianqian Li Guijin Su Jiaxin Pang Bohua Sun Jing Meng Bin Shi Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Developing industrially moldable catalysts with harmonized redox performance and acidity is of great significance for the efficient disposal of chlorinated volatile organic compounds(CVOCs)in actual exhaust ***,commercial TiO_(2),typically used for molding catalysts,was chosen as the carrier to fabricate a series of Ce_(0.02)Mn_(0-0.24)TiO_(x) materials with different Mn doping ratios and employed for chlorobenzene(CB)*** introduction of Mn remarkedly facilitated the synergistic effect of each element via the electron transfer processes:Ce^(3+)+Mn^(4+/3+)■Ce^(4+)+Mn^(3+/2+)and Mn^(4+/3+)+Ti^(4+)■Mn^(3+/2+)+Ti^(3+).These synergistic interactions in Ce_(0.02)Mn_(0.04-0.24)TiO_(x),especially Ce_(0.02)Mn_(0.16)TiO_(x),significantly elevated the active oxygen species,oxygen vacancies and redox properties,endowing the superior catalytic oxidation of *** the Mn doping amount increased to 0.24,a separate Mn_(3)O_(4) phase appeared,which in turn might weaken the synergistic ***,the acidity of Ce_(0.02)Mn_(0.04-0.24)TiO_(x) was decreased with the Mn doping,regulating the balance of redox property and ***,Ce_(0.02)Mn_(0.16)TiO_(x) featured relatively abundant B-acid *** coordinating redox ability and moderate acidity promoted the deep oxidation of CB and RCOOH-intermediates,as well as the rapid desorption of Cl species,thus obtaining sustainable *** comparison,CeTiO_(x) owned the strongest acidity,however,its poor redox property was not sufficient for the timely oxidative decomposition of the easier adsorbed CB,resulting in its rapid *** finding provides a promising strategy for the construction of efficient commercial molding catalysts to decompose the industrial-scale CVOCs.

关键词： Chlorobenzene Ce_(0.02)Mn_(0-0.2)4tiox materials Redox ability Acidity Synergistic interaction

Non-Existence of Entire Solution of a Type of System of Equations

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Journal of Mathematical Research with Applications 2024年第2期44卷 213-224页

作者： zhiwei zhou Ying ZHANG Zhigang HUANG School of Mathematics Suzhou University of Science and Technology Information Construction and Management Center Suzhou University of Science and Technology

In this paper, we will prove that the system of differential-difference equations■ has no transcendental entire solution(f(z), g(z)) with ρ(f, g) < ∞ such that λ(f) < ρ(f) andλ(g) < ρ(g), where P1(z), Q1(z), P2... 详细信息

关键词： transcendental entire function finite order system of differential-difference equations

Validation of risk scoring models for predicting stroke-associated pneumonia in patients with ischaemic stroke

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Stroke & Vascular Neurology 2016年第3期1卷 122-126页

作者： Siyin Gong zhiwei zhou Muke zhou Zhao Lei Jian Guo Ning Chen Li He Neurology Department West China Hospital of Sichuan UniversityChengduChina

Objective:Various risk scoring models have been developed to predict stroke-associated pneumonia(SAP).We aim to determine whether these risk models could effectively predict SAP in Chinese patients with ischaemic stroke(IS).Methods:Consecutive patients with IS in West China hospital between January 2011 and September 2013 were included to assess the predictive performance of risk scoring models,including Chumbler’s score,A^(2)DS^(2) and *** area under the receiver operating characteristic curve(AUROC)was used to evaluate the performance of each risk model in predicting ***:A total of 1569 consecutive patients with IS within 30 days of onset in West China hospital were *** incidence of pneumonia is 15.3%.The AUROC of Chumbler’s score,A^(2)DS^(2) and AISAPS was 0.659,0.728 and 0.758,respectively,and AISAPS had the highest ***:A^(2)DS^(2) and AISAPS had acceptable discriminatory abilities to predict SAP in Chinese patients with IS within 30 days of onset.

关键词： pneumonia patients predicting

Process Modeling and Control Simulation for a 500W@4.5K Helium Refrigerator

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Journal of Harbin Institute of Technology(New Series) 2016年第4期23卷 15-21页

作者： Xiaofei Lu zhiwei zhou Ming Zhuang Lilong Qiu Institute of Plasma Physics Chinese Academy of Sciences

In order to investigate dynamic behaviors of a 500W@ 4.5K helium refrigerator,the process simulator has been completed. The cryogenic process model is described and main components are customized. The realtime communication between the process model and the control system has been achieved. Compared with the preliminary experimental data,the errors of temperatures during the process of 300 K-80 K are less than 10%.The process model is validated to predict the cool-down process very well. The controller parameters are tuned in simulation and applied to the actual refrigerator suitably. Based on the dynamic simulation,the operation of Joule-Thomson( JT) by pass valve has been optimized. And the cool- down process from 300 K to 4. 5 K has been simulated under the control programs. Simulation results indicate that this dynamic simulator based on actual control architecture is available to process control and operation optimization for the helium refrigerators.

关键词： Helium refrigerator process simulation controller tuning operation optimization virtual commissioning