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Effect of Morphology and Age on the Closure Ability of Asian Box Turtles(Cuora)

Asian Herpetological Research 2022年第3期13卷 159-167页

作者： Fanrong xiao zhen HONG Haitao SHI Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158HainanChina Collegeof Agriculture and Rural Affairs Hainan Open UniversityHaikou 570208HainanChina

The ability of box turtles to close their shell as an antipredation adaptation and the potential impact of the anterior and posterior lobes of the plastron on the closing force and closing time remain relatively ***,keeled(Cuora mouhotii)and flowerback(***)box turtles,whose shell cannot and can be completely closed,respectively,were *** and posterior closing forces were measured using a force transducer,and the closing time was *** anterior closing force in both turtle species was substantially greater than the posterior closing force,reaching approximately 4-fold in ***,the anterior closing time in adults was significantly longer than the posterior closing *** closing force difference can be attributed to the substantially smaller anterior plastron lobe than the posterior lobe in the two ***,the anterior and posterior closing forces in both species positively correlated with body weight and showed no relationship with the length of the bridge and *** comparison showed that the anterior and posterior closing forces were significantly greater(approximately 2–4-fold)in flowerback box turtle than in keeled box turtles,regardless of age,and the closure time was significantly longer in adult flowerback box turtles than in adult keeled box *** the closing forces in both species showed negative allometry,the increase rate was significantly higher in flowerback box turtle than in keeled box *** closing forces in both species were observed to be approximately 4-fold stronger in adults than in *** sexual dimorphism concerning the anterior and posterior closing forces was observed in either *** summary,this is the first study to comparatively evaluate the anterior and posterior closing ability of box turtles,demonstrating that age,weight,plastron shape,and the degree of shell closure are important factors affecting closing ability.

关键词： anterior plastron lobe length closing force closing time Geoemydidae shell kinesis

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Reaction characteristics and kinetics of gallium in chlorination roasting of copper tailings using calcium chloride

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Rare Metals 2022年第3期41卷 1063-1070页

作者： Chang Lei Tao Chen Bo Yan xian-Ming xiao State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100082China

The mineral composition of copper tailings was examined, and the phase analysis of gallium was conducted for recovery of the rare scattered metal gallium from copper tailings. The reaction characteristics and kinetics of gallium in the chlorination roasting of copper tailings were investigated in a tube furnace apparatus under different conditions, including roasting temperature, quantity of chlorination agent,roasting time, and airflow. Calcium chloride was chosen for the chlorination reaction because it is highly effective for volatilization of metals. The results show that gallium mainly exists in limonites in the form of oxides, and increases in roasting temperature, quantity of chlorination agent, and roasting time are conducive to increasing the chloridizing volatilization rate of gallium. The tailings gradually melt when the roasting temperature exceeds 900℃, resulting in a decrease in the chloridizing volatilization rate of gallium. The chloridizing volatilization rate of gallium reaches 78.86%at roasting temperature of 900℃ for 40 min, airflow of 0.1 m^(3)·h^(-1), and calcium content of 33.33 wt%. Study of the reaction kinetics of gallium in chlorination roasting shows that the values of activation energy both for chemically controlled anddiffusion-controlled reactionsare44.64and11.93 kJ·mol^(-1), respectively. This indicates that the chemical reaction serves an important function in the chlorination volatilization of gallium. Taken together, the results reveal the usefulness of tailings as a source of rare metals and provide a basis for gallium recovery and environmentally friendly disposal of copper tailings.

关键词： Copper tailings Gallium recovery Chlorination roasting Calcium chloride Kinetics

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Chemical components and protective effects of Atractylodes japonica *** Kitam against acetic acid-induced gastric ulcer in rats

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World Journal of Gastroenterology 2023年第43期29卷 5848-5864页

作者： Bi-xian zhen Qian Cai Feng Li Department of Medicine Liaoning University of Traditional Chinese MedicineDalian 116600Liaoning ProvinceChina

BACKGROUND Atractylodes japonica *** Kitam.(***,Chinese name:Guan-Cangzhu,Japanese name:Byaku-jutsu),a perennial herb,which is mainly distributed in northeast area of China,it’s often used to treat digestive system diseases such as gastric ulcer(GU).However,the mechanism of its potential protective effects against GU remains *** To investigate the protective effects of *** on acetic acid-induced GU *** The chemical constituents of *** were determined by ultra performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)*** rat model of GU was simulated by acetic acid *** pathological changes of gastric tissues were evaluated by hematoxylin-eosin stain,the levels of epidermal growth factor(EGF),EGF receptor(EGFR),nuclear factor kappa-B(NF-κB),interleukin-1β(IL-1β),IL-10,Na^(+)-K^(+)-ATPase(NKA)in serum and gastric tissues were determined by enzyme-linked immunosorbent assay,and the mRNA expressions of EGFR,NF-κBp65,IkappaBalpha(IκBα)and Zonula Occludens-1(ZO-1)in gastric tissues were determined by real-time reverse transcription polymerase chain reaction,and the efficacy was ***,plasma metabolomic analysis was performed by UPLC-MS/MS to screen the specific potential biomarkers,metabolic pathways and to explore the possible *** 48 chemical constituents were *** of them have strong pharmacological activity,the results also revealed that *** significantly improved the pathological damage of gastric tissues,increased the expression levels of IL-10,IκBαrelated to anti-inflammatory factors,decreased the expression levels of IL-1β,NF-κB,NF-κBp65,related to proinflammatory factors,restored the levels of factors about EGF,EGFR,ZO-1 associated with ulcer healing and the levels of factors about NKA associated with energy *** analysis identified 10 potential differential metabolites and enriched 7 related metabolic *** These findings

关键词： Atractylodes japonica Koidz.ex Kitam. Ulcer Acetic acid Digestive system diseases Metabolomics Rats

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Flat-type permanent magnet linear alternator:A suitable device for a free piston linear alternator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 345-352页

作者： Qing-feng LI Jin xiao zhen HUANG MOE Key Laboratory for Power Machinery and Engineering Shanghai Jiao Tong University Shanghai 200240 China

We proposed the flat-type permanent magnet linear alternator (LA) for free piston linear alternators (FPLAs) instead of the tubular one. Using the finite element method (FEM), we compare these two kinds of LAs. The FEM result shows that the flat-type permanent magnet LA has higher efficiency and larger output specific power than the tubular one, therefore more suitable for FPLAs, and that the alternator design can be optimized with respect to the permanent magnet length as well as the air gap.

关键词： Free piston (FP) Linear alternator (LA) Internal combustion engine (ICE) Finite element method (FEM)

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Hot compression deformation behavior of biomedical Ni-Ti alloy

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Rare Metals 2019年第7期38卷 609-619页

作者： zhen Wang xiao-Wen Xu Bing Zhang School of Physics and Electronics Central South University Changsha 410083 China School of Basic Medical Science Central South University Changsha 410083 China School of Metallurgical Engineering Xi'an University of Architecture and Technology Xi'an 710000. China

Biomedical Ti-55.78 (wt%) Ni alloy samples were prepared by vacuum induction melting, and their hot compression deformation behavior was studied in the deformation temperature range of 750-950℃, the strain rate range of 0.001-1.000 s^-1 and the true strain range of 0.1 -0.7. The constitutive equation of the as-cast biomedical Ni-Ti alloy was established based on the Arrhenius constitutive model, and error analysis of the constitutive equation was carried out. The processing zone and unstable thermal deformation zone of the as-cast biomedical Ni-Ti alloy were obtained by establishing hot processing maps based on a dynamic material model. The results showed that deformation temperature and strain rate were the main factors affecting the flow stress. The results of error verification of the constitutive equation show that the predicted flow stress curves agree well with the measured ones. Therefore, the constitutive equation based on Arrhenius can accurately predict the high temperature flow stress of as-cast biomedical Ni-Ti alloy. The optimum parameters for forging process of biomedical Ni-Ti alloy are the strain rate less than 0.003 s^-1 and the hot deformation temperature range of 930-950℃.

关键词： Biomedical Ni-Ti alloy Hot compression deformation Constitutive equation Hot processing map

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Etiology for Degenerative Disc Disease

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Chinese Medical Sciences Journal 2016年第3期31卷 185-191页

作者： Dhungana Hemanta xiao-xing Jiang zhen-zhou Feng Zi-xian Chen Yuan-wu Cao Department of Orthopedics Zhongshan HospitalFudan University

Degenerative disc disease is a multifaceted progressive irreversible condition and an inevitable part of aging,which has been found to be a contributing factor for low back pain and might cause radiculopathy,myelopathy,spinal stenosis,degenerative spondylolisthesis,and *** etiology is complex and *** genetics influence more dominant,the occupational and mechanical influences still persist as a major risk *** review emphasizes up-to-date knowledge regarding etiology of disc degeneration with special consideration on occupational,lifestyle factors,and genetic polymorphisms.

关键词： degenerative intervertebral disc disease cervical spine genetics back pain

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Existence and Nonexistence of Global Positive Solutions for a Weakly Coupled P-Laplacian System

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Acta Mathematicae Applicatae Sinica 2013年第3期29卷 541-554页

作者： xian-zhong ZENG zhen-hai LI Yong-geng GU School of Mathematics and Computing Science Hunan University of Science and Technology College of Science Guangxi University for Nationalities Department of Mathematics Hunan Normal University

In this paper, we deal with a weakly coupled evolution P-Laplacian system with inhomogeneous terms. We obtain a critical criterion concerning existence and nonexistence of its global positive solutions. Such a criterion is different from that of the weakly coupled evolution P-Laplacian system with homogeneous terms. Further, we demonstrate existence and nonexistence of its global positive solutions.

关键词： the evolution P-Laplacian system inhomogeneous terms blow-up global existence

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Design and modeling of a free-piston engine generator

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Frontiers in Energy 2023年第6期17卷 811-821页

作者： Jinlong WANG Jin xiao Yingdong CHENG zhen HUANG Key Laboratory for Power Machinery and Engineering(Ministry of Education) Shanghai Jiao Tong UniversityShanghai 200240China

Free-piston engine generators (FPEGs) can be applied as decarbonized range extenders for electric vehicles because of their high thermal efficiency, low friction loss, and ultimate fuel flexibility. In this paper, a parameter-decoupling approach is proposed to model the design of an FPEG. The parameter-decoupling approach first divides the FPEG into three parts: a two-stroke engine, an integrated scavenging pump, and a linear permanent magnet synchronous machine (LPMSM). Then, each of these is designed according to predefined specifications and performance targets. Using this decoupling approach, a numerical model of the FPEG, including the three aforementioned parts, was developed. Empirical equations were adopted to design the engine and scavenging pump, while special considerations were applied for the LPMSM. A finite element model with a multi-objective genetic algorithm was adopted for its design. The finite element model results were fed back to the numerical model to update the LPMSM with increased fidelity. The designed FPEG produced 10.2 kW of electric power with an overall system efficiency of 38.5% in a stable manner. The model provides a solid foundation for the manufacturing of related FPEG prototypes.

关键词： free-piston engine generator linear permanent magnet synchronous machine system design numerical model finite element method

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ASYMPTOTIC BEHAVIOR OF SOLUTION BRANCHES OF NONLOCAL BOUNDARY VALUE PROBLEMS

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Acta Mathematica Scientia 2020年第2期40卷 341-354页

作者： xian XU Baoxia QIN zhen WANG Department of Mathematics Jiangsu Normal UniversityXuzhou 221116China School of Mathematics Qilu Normal UniversityJinan 250013China

In this article, by employing an oscillatory condition on the nonlinear term,a result is proved for the existence of connected component of solutions set of a nonlocal boundary value problem, which bifurcates from infinity and asymptotically oscillates over an interval of parameter values. An interesting and immediate consequence of such oscillation property of the connected component is the existence of infinitely many solutions of the nonlinear problem for all parameter values in that interval.

关键词： Global solution branches Leray-Schauder degree asymptotic oscillation property

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Solid phase synthesis of peptide–siRNA conjugates containing disulfde bond unit

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Chinese Chemical Letters 2013年第10期24卷 873-876页

作者： xiao-Feng Wang xian-Tao Yang Yue Chen Yang Liu Lang Zou zhen-Jun Yang Li-He Zhang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University

A disulfide-modified nucleoside was designed and synthesized. After loading the modified nucleoside on controlled pore glass （CPG）, solid phase synthesis strategy was used to prepare peptide-oligonucleotide conjugates （N-3＇） containing disulfide bond unit. The 3＇-sense strand peptide-siRNA conjugate （VII） maintained good gene silencing activity, while that of the 3＇-antisense strand conjugate decreased somewhat. And the sense strand off-target effect of VII decreased remarkably.

关键词： siRNA Solid synthesis Disulfide bond Peptide Conjugate

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