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China Ocean Engineering 2019年第4期33卷 446-458页

作者： YU Yang-zhe feng Guo-qing li chen-feng REN Hui-long College of Shipbuilding Engineering Harbin Engineering University

The study of the ultimate strength of stiffened plates is a hot topic in ocean engineering. The ultimate strength and behavior of collapse of stiffened plates were investigated using experimental and numerical methods. Two stiffened plates, with one and two half-bays in both longitudinal and transverse directions, were tested under the uniaxial compression. There were clamped boundaries at both ends of the stiffened panels and a restrained boundary on the transverse frames. The novel three-dimensional laser scanning technology was used to measure the initial geometric imperfections and the ultimate deformation of the stiffened panels after the test. The initial geometric deformation was imported into the finite element model, and the ultimate strength and behavior of collapse of the stiffened plates were calculated using the finite element analysis. FE analysis results based on the measured initial geometric imperfections were compared with the test results. It is concluded that structural deformation can be well measured by three-dimensional laser scanning technology, and can be conveniently imported into the finite element analysis. With the measured initial geometric imperfections considered, the FE analysis results agree well with the experimental results in ultimate strength, behavior of collapse, and the ultimate displacement distribution of the stiffened panels.

关键词： Stiffened plate ultimate strength experiment three dimensional laser scanning initial geometric imperfection

Electrophysiological changes of autonomic cells in left ventricular outflow tract in guinea pigs with iron deficiency anemia complicated with chronic heart failure

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1197-1200页

作者： ling Fan li-feng chen Jing Fan Department of Hematology The First Affiliated Hospital of Hebei North University Department of Physiology Basic Medical College Hebei North University Department of Obstetrics and Gynecology The Sixth Hospital of Zhangjiakou

Objective: To investigate the electrophysiological changes of autonomic cells in left ventricular outflow tract in guinea pigs with iron deficiency anemia complicated with chronic heart ***: Guinea pigs model of iron deficiency anemia complicated with chronic heart failure in 10 guinea pigs of the experimental group was made by feeding a low iron diet,pure water and subcutaneous injection of isoproterenol. The control group consisting of 11 guinea pigs was given normal food, normal water and injected with normal saline. The left ventricular outflow tract model specimen was also prepared. The standard microelectrode technique was used to observe electrophysiological changes of autonomic cells in the outflow tract of left ventricular heart failure complicated with iron deficiency anemia in guinea pig model. The indicators of observation were maximal diastolic potential, action potential amplitude, 0 phase maximal depolarization velocity, 4 phase automatic depolarization velocity, repolarization 50% and 90%, and spontaneous discharge ***: Compared with the control group, 4 phase automatic depolarization velocity,spontaneous discharge frequency and 0 phase maximal depolarization velocity decreased significantly(P litude reduced(P lities of the left ventricular outflow tract in guinea pigs with iron deficiency anemia complicated with heart failure.

关键词： Iron deficiency anemia Chronic heart failure Guinea pig model Autonomic cells Left ventricular outflow tract Electrophysiology

Biotemplated synthesis of three-dimensional porous MnO/C-N nanocomposites from renewable rapeseed pollen： An anode material for lithium-ion batteries

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Nano Research 2017年第1期10卷 1-11页

作者： li-feng chen Sheng-Xiang Ma Shu Lu Yue feng Jia Zhang Sen Xin Shu-Hong Yu Division ofNanomatefials & Chemistry Hefei National Laboratory for Physical Sciences at Microscale Collaborative Innovation Center of Suzhou Nano Science and Technology CAS Center for Excellence in Nanoscience Department of Chemistry Department of Materials Science & Engineering University of Science and Technology of China Hefei 230026 China Anhui Key Laboratory of Controllable Chemical Reaction and Material Chemical Engineering School of Chemical Engineering Hefei University of Technology Hefei 230009 China

lithium-ion batteries （liBs） are currently recognized as one of the most popular power sources available. To construct advanced liBs exhibiting long-term endurance, great attention has been paid to enhancing their poor cycle stabilities. As the performance of liBs is dependent on the electrode materials employed, the most promising approach to improve their life span is the design of novel electrode materials. We herein describe the rational design of a three-dimensional （3D） porous MnO/C-N nanoarchitecture as an anode material for long cycle life liBs based on their preparation from inexpensive, renewable, and abundant rapeseed pollen （R-pollen） via a facile immersion-annealing route. Remarkably, the as-prepared MnO/C-N with its optimized 3D nanostructure exhibited a high specific capacity （756.5 mAh·g^-1 at a rate of 100 mA·g^-1）, long life span （specific discharge capacity of 513.0 mAh·g^-1, -95.16% of the initial reversible capacity, after 400 cycles at 300 mA·g^-1）, and good rate capability. This material therefore represents a promising alternative candidate for the high-performance anode of next-generation liBs.

关键词： 3D porous MnO/C-Nnanocomposite rapeseed pollen renewable biomass lithium-ion batter long cycle life

Effects of probiotic therapy on hepatic encephalopathy in patients with liver cirrhosis:an updated meta-analysis of six randomized controlled trials

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 354-360页

作者： Jun Xu Rui Ma li-feng chen li-Jun Zhao Kan chen Ren-Bing Zhang Department of Surgery Zhejiang University Hospital Zhejiang University

BACKGROUND： liver cirrhotic patients with hepatic encephalopathy have poor prognosis. Probiotics alter the intestinal microbiota and reduce the production of ammonia. We conducted a meta-analysis about the role of probiotics on liver cirrhotic patients with hepatic *** SOURCES： We collected the relevant literatures up to February 21, 2014 from databases of PubMed, EMBASE and the Cochrane Central Register of Controlled Trials. A statistical analysis was conducted by RevMan 5.2 and STATA 12.0 ***： Six randomized controlled trials involving 496 liver cirrhotic patients were included. The results showed that probiotic therapy significantly reduced the development of overt hepatic encephalopathy（OR [95% CI]： 0.42 [0.26, 0.70],P=0.0007）. However, probiotics did not affect mortality, levels of serum ammonia and constipation（mortality： OR [95% CI]：0.73 [0.38, 1.41], P=0.35; serum ammonia： WMD [95% CI]：-3.67 [-15.71, 8.37], P=0.55; constipation： OR [95% CI]： 0.67 [0.29,1.56], P=0.35）.CONCLUSION： Probiotics decrease overt hepatic encephalopathy in patients with liver cirrhosis.

关键词： probiotics hepatic encephalopathy liver cirrhosis ammonia meta-analysis

The reversible addition-fragmentation chain transfer(RAFT) miniemulsion polymerization of vinyl acetate mediated by xanthate

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Chinese Chemical Letters 2009年第6期20卷 733-737页

作者： Bo Jiang Qing Hua Zhang Xiao li Zhan feng Qiu chen Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 People's Republic of China

The reversible addition-fragmentation chain transfer （RAFT） miniemulsion polymerization of vinyl acetate （VAc） mediated by methyl （methoxycarbonothioyl） sulfanyl acetate （MMSA） was carried out. The results showed that polymerizations initiated by AIBN and KPS proceeded in a controlled way. The RAFT miniemulsion polymerization of VAc initiated by KPS showed the shorter inhibition period, higher propagation rate coefficient and final conversion than those in experiment initiated by AIBN. When the monomer conversion reached 25%, the polydispersity index （PDI） of polymer became broad, which was related to chain transfer reaction in RAFT miniemulsion of VAc.

关键词： Xinyl acetate Xanthate Reversible addition-fragmentation chain transfer Miniemulsion

Gradual or Hysteretic Transition:Anion Effects on Cobalt(II)Spin Crossover Complexes

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Chinese Journal of Chemistry 2024年第19期42卷 2381-2390页

作者： Yu-chen Sun Ying-lian li cheng-cheng Zhang feng-li chen Dong Shao Yue Zhao Hai-Yan Wei Xin-Yi Wang State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu 210023China Jiangsu Key Laboratory of Biofunctional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjingJiangsu 210023China Hubei Key Laboratory of Processing and Application of Catalytic Materials College of Chemistry and Chemical EngineeringHuanggang Normal UniversityHuanggangHubei 438000China

Comprehensive Summary To better understand the impact of different anions on the structures and SCO properties of the CoII SCO complexes,six new complexes[Co(terpy-CH_(2)OH)_(2)]A_(2)·sol(terpy-CH_(2)OH=4′-(hydroxymethyl)-2,2′;6′,2″-terpyridine,A=Br^(–)(1,sol=1.5H_(2)O),I^(–)(2),N_(3)^(–)(3,sol=2H_(2)O),H_(3)BCN^(–)(4),OTf^(–)(5),and TsO^(–)(6,sol=4H_(2)O·CH_(3)CN),have been synthesized and *** six compounds consist of mononuclear[Co(terpy-CH_(2)OH)_(2)]^(2+)cations and charge-balancing anions that differ in size,shape,and hydrogen bonding *** 1,2,3,and 6 displayed incomplete gradual SCO transitions,whereas 4 and 5 exhibited abrupt hysteretic spin transitions with loops of 12 and 16 K(250.0—262.0 K for 4,and 370.0—386.0 K for 5,respectively),closely resembling our previously reported complexes with SCN^(–)and SeCN^(–)*** occurrence of the order-disorder transition of the CH2OH groups and their transition temperatures are determined by the size and hydrogen bonding capability of the ***,the transition temperatures of complexes with H_(3)BCN^(–),SCN^(–),OTf^(–),and SeCN^(–)anions exhibit an upward trend as the size and mass of the anions increase,as confirmed through detailed single crystal structure analyses conducted in both high-spin and low-spin states for all four complexes.

关键词： Cobalt Solid-state structures Magnetic properties Spin crossover Anion effect

Monomer reactivity ratios for fluoroacrylate and butyl methacrylate in miniemulsion copolymerizations initiated by potassium persulphate

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Chinese Chemical Letters 2009年第4期20卷 478-482页

作者： Qing Hua Zhang Zhen Huan Luo Xiao li Zhan feng Qiu chen College of Materials Science and Chemical Engineering Zhejiang University Hangzhou 310027 China

Miniemulsion copolymerization of butyl mathacrylate （BMA） with fluoroacrylate （HFMA, TFMA） was carried out at 70 ℃ by employing potassium persulphate （KPS） as initiator. Copolymer compositions at low conversion levels were determined by ^1H NMR spectra techniques. The reactivity ratios were evaluated by employing Kellen-Tudos （K-T） methods, which yields the apparent reactivity ratios, rBMA = 0.74, rHFMA = 0.87 and rBMA = 0.73, rTFMA = 0.75, respectively, and Q- and e-values of HFMA and TFMA were calculated by the Alfrey-Price method. The results show that HFMA and TFMA are more active than BMA, and the cross-propagation rate constant is greater than the self-propagation one in these two copolymerizations.

关键词： Fluoroacrylate Reactivity ratios Miniemulsion Copolymerization

Precise separation and efficient recovery of Pd(Ⅱ)from high-level liquid waste by XAD-based adsorbents

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Rare Metals 2024年第10期43卷 5372-5390页

作者： Hao-Ran Dong Shun-Yan Ning Zeng-Yuan li Si-Zhi Xu feng-Tao Hu feng Gao You-Bin Wang li-feng chen Xiang-Biao Yin Toyohisa Fujita Mohammed FHamza Yue-Zhou Wei School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China School of Nuclear Science and Technology University of South ChinaHengyang 421001China

Efficient separation of palladium(Pd(Ⅱ))from high-level liquid waste(HLLW)not only helps the safe disposal of nuclear waste,but also is a vital importan supplement to Pd(Ⅱ)***,16 kinds of nove Amberlite XAD resins-based adsorbents were prepared by vacuum impregnation method for the separation of Pd(Ⅱ)from simulated HLLW,and the MMBT/XAD7HP prepared using 4-methyl-2-mercaptobenzothiazole(MMBT)as ligand and Amberlite XAD7HP resin(XAD7HP)as the carrier was selected as the optimal research *** analysis experiments proved the successful preparation of MMBT/XAD7HP,which exhibited ultrahigh adsorption selectivity for Pd(Ⅱ)(distribution coefficient(K_d)≥12584.5 ml·g^(-1),separation factor(SF_(Pd/M))≥2818.4)and superior adsorption capacity(Q≥130.1 mg·g^(-1)).The adsorption kinetics and adsorption isotherms for Pd(Ⅱ)matched with pseudo-secondorder(PSO)kinetics model and Langmuir model,indicating that the adsorption mode for Pd(Ⅱ)by MMBT/XAD7 HP was monolayer chemical *** dynamic column experiments showed that MMBT/XAD7 HP achieved efficiently separation of Pd(Ⅱ)from simulated HLLW,and the recovery rate was nearly 100% The adsorption mechanism was analyzed by Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT),and the ultrahigh selectivity of MMBT/XAD7 HP is attributed to the preferred affinity of the soft-N,S donor atoms in MMBT for Pd(Ⅱ).MMBT has the shortest frontline molecular orbital energy band gap(HOMO-LUMO)among the four ligands,which makes it easier to become an electron donor to attract Pd^(2+)to participate in ***_(3)^(-)participates in the adsorption to keep charge *** summary,MMBT/XAD7 HP has broad application prospects for the treatment of Pd(Ⅱ)in HLLW.

关键词： XAD Palladium HLLW Adsorption Column experiments

The experimental studies on the carbon and nitrogen budgets of Pseudeuphausia sinica

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Acta Oceanologica Sinica 2003年第2期22卷 265-272页

作者： Guo Donghui, li Shaqjing, chen feng, Wang Guizhong, chen Gang Department of Oceanography,Institute of Subtropic Ocean,Xiamen University,Xiamen 361005,China Xiamen Univ Dept Oceanog Inst Subtrop Ocean Xiamen 361005 Peoples R China

The carbon and nitrogen budgets were estimated on the adult females, juveniles and post-furcilia larvae of Pseudeuphausia sinica fed on newly hatching nauplii of Artemia salina in the laboratory. It was found that the ingestion rate was linearly related to the food concentration, suggesting high feeding potential. The linear correlation could be established between the respirating rate (carbon consumption rate) and carbon ingestion rate, as well as carbon assimilation rate. The regression coefficients (*** dynamic action coefficients) were in the range from 9% to 16% (ingested C) or 10% to 17% (assimilated C) respectively, with lower in the post-furcilia larvae. There also existed a linear correlation equation between estimated total nitrogen excretion rate and the rates of nitrogen ingestion and assimilation separately, except for the juveniles. The defecation rates increased with the increase of the ingestion rate; as a result, assimilation efficiency was not related to the ingestion rate, ranging from 0.84 to 0.95. The results inducated that the nitrogen content in food particles was a key factor limiting the growth of P. sinica. The critical ingestion rate was 10 μgN·mg-1 body dry weight per day. Assimilated N was lost mostly by excretion, following allocated to somatic growth. The nitrogen loss by moult only accounted for a minor part. As for carbon budget, respiration and somatic growth also accounted for most of assimilation, but varied with ingestion rates. Moult loss was minor. Estimated reproductive growth (C&N) in the adult females accounted for somewhat higher percent of assimilation than the moult growth. The net growth efficiency (K2) increased with the increase of the ingestion rates, but decreased slightly for juvenile and post-furcilia larvae after the rates up to a certain value.

关键词： Pseudeuphausia. sinica carbon and nitrogen budgets Xiamen harbour

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF FREE SURFACE VORTEX

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Journal of Hydrodynamics 2008年第4期20卷 485-491页

作者： li Hai-feng chen Hong-xun MA Zheng ZHOU Yi Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China China Ship Scientific Research Center Wuxi 214082 China

An experimental model was set up to investigate the formation and evolution of the free surface vortex. A Particle Image Velocimetry （PIV） was used to measure the free surface vortex flow field at different development stages. Flow visualization was used to locate the vortex position and find its structure. Empirical formulas about the critical submergence and the whole field structure were obtained. It is found that the tangential velocity distribution is similar to that of the Rankine vortex and the radial velocity changes little in the vortex functional scope. Vortex starts from the free surface and gradually intensifies to air entrainment vortex. The vortex core moves during the formation and evolution of the free surface vortex. Based on the experimental model, the vortex position and structure were predicted by numerical simulation combined with a vortex model and compared with that of the experiments, which shows satisfactory agreement.

关键词： free surface vortex Particle Image Velocimetry (PIV) numerical simulation rankine vortex