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Improvement on the Mechanical Performance and Resistance Towards Hydrolysis of Poly(glycolic acid)via Solid-state Drawing

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chinese journal of Polymer Science 2023年第1期41卷 14-23页

作者： jia-Xuan Li De-Yu Niu Bo Liu Peng-Wu Xu Wei-jun yang Pieter jan Lemstra Pi-Ming Ma The Key Laboratory of Synthetic and Biological colloids Ministry of EducationJiangnan UniversityWuxi214122China PlemPolco B.V. Roek 245508 KEVeldhoventhe Netherlands

Poly(glycolic acid)is a biocompatible as well as biocomposable polymer with superior mechanical and barrier properties and,consequently,has found important applications in both medical and packaging ***,the high hydrolysis rate in a high humidity environment restricts its *** this work,a solid-state drawing process after melt extrusion is applied in order to produce fibrous PGA with enhanced mechanical properties and a much better resistance towards *** crystal structure of PGA gradually transformed from spherulites into oriented fibrous crystals in the stretching direction upon solid-state ***,both the length of microfibril and the size of lamellae increased initially with the drawing ratio(DR),while the chain-folded lamellae transformed into extended-chain fibrils at high(er)*** oriented structures lead to an overall improvement of the mechanical properties of PGA,e.g.,the tensile strength increased from 62.0±1.4 MPa to 910±54 MPa and the elongation at break increased from around 7%to 50%.Meanwhile,the heat capacity of totally mobile amorphous PGA(∆c_(p)^(0)=0.64 j·g^(−1)·℃^(−1))was reported for the first time,which was used to analyze the content of mobile amorphous fraction(XMAF)and rigid amorphous fraction(XRAF).Both the oriented chain-folded lamellae crystals and the tightly arranged RAF are beneficial to prevent water molecules from penetrating the matrix,thus improving the resistance towards *** a consequence,the fibrous PGA with a DR of 5 showed a tensile strength retention rate of 17.3%higher in comparison with the undrawn sample after 7-days accelerated ***,this work provides a feasible method to improve the mechanical and resistance towards hydrolysis performance of PGA,which may broaden its application and prolong the shelf-life of PGA products.

关键词： Poly(glycolic acid) Solid-state drawing Fibrous crystal Mechanical property Hydrolysis resistance

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Effect of Nb doping on microstructure and magnetic properties of hot-deformed Nd-Fe-B magnets with Nd-cu eutectic diffusion

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journal of Materials Science & Technology 2022年第27期122卷 121-127页

作者： Tingting Song Xin Li Xu Tang Wenzong Yin yang Luo Dunbo Yu Wenlong Yan jinyun ju Renjie chen Aru Yan School of Marine Engineering Equipment Zhejiang Ocean UniversityZhoushan 316022China cAS Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo 315201China Grirem Advanced Materials co. Ltd.Beijing 100049China

To restrict grain growth in coarse grain regions caused by the diffusion of Nd-cu eutectic alloys,the Nb element was introduced into the precursor alloy to regulate the microstructure of melt-spun powder and die-upset *** magnetic properties and thermal stability of die-upset magnets were appreciably improved through the addition of *** the Nb-doped diffusion die-upset magnet,the grains inside the ribbons were refined and the coarse non-oriented surface crystallite got suppressed on the interface of ribbons during the hot-deformation process to form the anisotropic ***,Nd gathers at the intergranular phases,which is considered to enforce domain wall pinning *** Nb-modified microstructure is advantageous to thermal stability and coercivity ***-resolution transmission electron microscopy images revealed that the Nb element gathered on the grain boundary and triple grain boundary to form c-Nb and h-Nb Fe B to hinder the grain growth during the hot-deformation process,which led to direct enhancement in the ***,the c-Nb and h-Nb Fe B are nonmagnetic phases that strengthened the magnetic ***,the h-Nb Fe B precipitated from the hard magnetic phase and formed crystal defects which led to remanence deterioration.

关键词： Nd-Fe-B Hot deformation Diffusion Nb-doping coercivity

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Regional Allocation of cO_2 Intensity Reduction Targets Based on cluster Analysis

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Advances in climate change Research 2012年第4期3卷 220-228页

作者： yang Yuan cAI Wen-jia WANG can WANG Si-Qiang School of Environment Tsinghua University center for Earth System Science Tsinghua University National Energy Administration

To meet china＇s cO2 intensity target of 40%-45% reduction by 2020 based on the 2005 level, a regional allocation method based on cluster analysis is developed. Thirty chinese provinces are classified into six groups based on economy, emissions, and reduction potential indicators. Under the equity principle, the two most developed groups axe assigned the highest reduction targets （55% and 65%, respectively）. However, their reduction potent!al is limited. Under the efficiency principle, the two groups with the highest reduction potential take the highest targets （48% and 61%, respectively）, but their economy is relatively backward. When equity and efficiency are equally weighted, the 5th group with a prominent reduction potential takes the highest target （54%）, and the 2nd and the 3rd groups with large industry scales take the second highest target （49%）. However, under all the three allocation schemes, the targets are not greater than 40% for the 4th and the 6th groups, which have a relatively low economic ability, emissions, and reduction potential. Due to inconsistency between economic and reduction potential, corresponding market mechanisms and policy instruments should be established to ensure equity and efficiency of regional target allocation.

关键词： c02 intensity reduction targets allocation cluster analysis regional difference

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Micropore engineering on hollow nanospheres for ultra-stable sodium-selenium batteries

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journal of Energy chemistry 2023年第5期80卷 99-109,I0004页

作者： Gongke Wang Yumeng chen Yu Han Lixue yang Wenqing Zhao changrui chen Zihao Zeng Shuya Lei Shaohui Yuan Peng Ge School of Materials Science and Engineering Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage MaterialsHenan Normal UniversityXinxiang 453007HenanChina comprehensive Energy Research center Institute of Science and TechnologyChina Three Gorges CorporationBeijing 100038China School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Attracted by high energy density and considerable conductivity of selenium(Se),Na-Se batteries have been deemed promising energy-storage ***,it still suffers from sluggish kinetic behaviors and similar“shuttling effect”to ***,utilizing uniform hollow carbon spheres as precursors,Se-material is effectively loaded through vapor-infiltration *** to the distribution of optimized pores,the content of microspores could be up to~60%(cal confinement ***,the rich oxygen-containing groups and N-elements could be noted,inducing the evolution of electron-moving *** significantly,assisted by the interfacial c-Se bonds and tiny Se distributions,Se electrodes are activated during *** as cathodes for Na-Se systems,the as-resulted samples display a capacity of 593.9 mA h g^(-1)after 100 cycles at the current density of 0.1 *** after 6000 cycles,the capacity could be still kept at about 225 mA h g^(-1)at 5.0 *** by the detailed kinetic analysis,the designed microspores size induces the increasing redox reaction of nano Se,whilst the surface traits further render the enhancement of pseudo-capacitive ***,after cycling,the product Sex(xctive *** this,the work is anticipated to provide an effective strategy for advanced electrodes for Na-Se systems.

关键词： carbon host Tailoring pores Heteroatom doping Vapor-infltration method Sodium-selenium batteries

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Effect of titanium on the wettability between Fe-P-Ti alloy and Al2O3 substrate

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Progress in Natural Science:Materials International 2024年第3期34卷 555-561页

作者： Rui Wang Shengjie Bai Xu chen Likui Xie Zhiqiang Yu yang Kang Yihong Li Yong Hu Zhiyue Shi Zhijie Yan School of Materials Science and Engineering North University of China Shanxi Key Laboratory of Advanced Metal Materials for Special Environments North University of China cISDI Engineering cO. LTD. School of Materials Science and Engineering Taiyuan University of Science and Technology

It is of significance that the wettability between the molten alloy and the Al2O3affects the inclusion removal,nozzle clogging and refractory erosion. In the present work, the wettability between the Al2O3substrate and Fe–P–Ti alloys with different Ti content was investigated by using the sessile droplets method. The interfacial characteristics were investigated by scanning electron microscope（SEM）. The contact angles between the sintered Al2O3substrate and Fe–P–Ti alloys with 0, 0.05, 0.10 and 0.15 wt% Ti are 100.1°, 97.3°, 94.5°and 90.5°,respectively. The oxidation of [Al] and [Ti] in the molten alloys leads to the formation of the oxides on the droplets. With the increase of Ti content in the Fe–P–Ti alloys, the formed oxides change from Al2O3to Ticontaining oxides. The reaction between [Ti] and Al2O3substrate in the interface results in the formation of Ti-containing oxides. The quantity of the interfacial oxides increases with the increase of Ti content in the *** a result, the synergetic effect of the formation of the interfacial products and the oxides on the surface of droplets leads to the decrease of the contact angles between the Al2O3substrate and Fe–P–Ti alloys due to the increase of Ti content.

关键词： Al2O3 substrate contact angle Fe–P–Ti alloys Interfacial reaction Wettability

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Elasto-Plastic FEM Analysis of Residual Stress in Spun Tube

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journal of Materials Science & Technology 2004年第4期20卷 379-382页

作者： Fuan HUA, Yuansheng yang, Dayong GUO, Wenhui TONG and Zhuangqi HUInstitute of Metal Research, chinese Academy of Sciences, Shenyang 110016, china Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The residual stress distribution of Hastelloy c corrosion-resistant alloy tubes after power spinning was simulated with the elasto-plastic finite element method combining with the element birth and death technique, the influences of spinning parameters on the distribution of the residual stress were investigated in detail, and the formation mechanism of residual stress during tube spinning was discussed. Based on the calculation of the residual stress, the reasons for annealing cracks on the spun tube during interpass heat treatment were explored. The simulation results and the characteristics of annealing cracks show that the circumferential residual tensile stress is a main factor to cause the annealing cracks.

关键词： Residual stress Power spinning Annealing cracks Elasto-plastic FEM Element birth and death

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Enhanced methane production in an anaerobic digestion and microbial electrolysis cell coupled system with co-cultivation of Geobacter and Methanosarcina

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journal of Environmental Sciences 2016年第4期28卷 210-214页

作者： Qi Yin Xiaoyu Zhu Guoqiang Zhan Tao Bo Yanfei yang Yong Tao Xiaohong He Daping Li Zhiying Yan Key Laboratory of Environmental and Applied Microbiology Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China Environmental Microbiology Key Laboratory of Sichuan Province Chengdu 610041 China

The anaerobic digestion（AD）and microbial electrolysis cell（MEc）coupled system has been proved to be a promising process for biomethane *** this paper,it was found that by co-cultivating Geobacter with Methanosarcina in an AD–MEc coupled system,methane yield was further increased by 24.1%,achieving to 360.2 m L/g-cOD,which was comparable to the theoretical methane yield of an anaerobic *** the presence of Geobacter,the maximum chemical oxygen demand（cOD）removal rate（216.8 mg cOD/（L·hr））and current density（304.3 A/m3）were both increased by 1.3 and 1.8 fold compared to the previous study without Geobacter,resulting in overall energy efficiency reaching up to 74.6%.community analysis demonstrated that Geobacter and Methanosarcina could coexist together in the biofilm,and the electrochemical activities of both were confirmed by cyclic *** study observed that the carbon dioxide content in total gas generated from the AD reactor with Geobacter was only half of that generated from the same reactor without Geobacter,suggesting that Methanosarcina may obtain the electron transferred from Geobacter for the reduction of carbon dioxide to *** together,Geobacter not only can improve the performance of the MEc system,but also can enhance methane production.

关键词： AD–MEc coupled system Geobacter Methanosarcina co-cultivation Methane production

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Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

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Pedosphere 2021年第2期31卷 243-254页

作者： Márcio R.MARTINS Leonardo F.SARKIS Selenobaldo A.c.SANT’ANNA camila A.SANTOS Karla E.ARAUjO Ricardo c.SANTOS Ednaldo S.ARAÚjO Bruno j.R.ALVES claudia P.jANTALIA Robert M.BODDEY Mohammad ZAMAN Segundo URQUIAGA Embrapa Agrobiology Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Federal Rural University of Rio de janeiro(UFRRj) Rod.BR 465km 7Seropédica RJ CEP 23891-000(Brazil) Agroscope Research Division Agroecology and EnvironmentClimate and Agriculture GroupReckenholzstrasse 191Zurich 8046(Switzerland) Soil and Water Management&crop Nutrition Joint FAO/IAEA Division of Nuclear Techniques in Food&AgricultureP.O.Box 100Vienna A-1400(Austria)

Measuring ammonia(NH_(3))volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen(N)losses in *** small area of chambers used for NH_(3)volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are *** aims were:i)to investigate the effect of using multiple open chambers on the variability in the measurement of NH_(3)volatilization in urea-amended field plots and ii)to define the critical period of NH_(3)-N losses during which the concentration of sampling effort is capable of reducing *** use of only one chamber covering 0.015%of the plot(51.84 m^(2))generates a value of NH_(3)-N loss within an expected margin of error of 30%around the true *** reduce the error margin by half(15%),3–7 chambers were required with a mean of 5 chambers per *** the sampling efforts in the first two weeks after urea application,which is usually the most critical period of N losses and associated errors,represents an efficient strategy to lessen uncertainty in the measurements of NH_(3)*** strategy enhances the power of detection of NH_(3)-N loss abatement in field experiments using chambers.

关键词： chamber method experimental error gas emission low-cost chamber nitrogen cycling nitrogen loss soil variability

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重连口服液联合抗感染治疗成人社区获得性肺炎临床研究

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临床肺科杂志 2025年第1期30卷 27-30页

作者：方莉杨程童佳兵高雅婷童祥丽安徽中医药大学第一附属医院安徽合肥230032 安徽中医药大学安徽合肥230031

目的对重连口服液联合抗感染用于成人社区获得性肺炎(community acquired pneumonia, cAP)患者的临床治疗效果以及临床不良反应予以观察。方法成人cAP患者80例,通过随机分组,形成对照组和治疗组,每组各40例。对照组采用传统的西医学... 详细信息

目的对重连口服液联合抗感染用于成人社区获得性肺炎(community acquired pneumonia, cAP)患者的临床治疗效果以及临床不良反应予以观察。方法成人cAP患者80例,通过随机分组,形成对照组和治疗组,每组各40例。对照组采用传统的西医学临床治疗方案,治疗组在此治疗基础上使用重连口服液。对治疗组和对照组患者的临床症状改善程度以及药物应用效果进行观察,比较两组治疗前后的血常规、炎性相关指标以及临床不良反应。结果治疗组比对照组有更高的治疗总有效率(Pc-反应蛋白(hs-cRP)、外周血降钙素原(PcT)、血清淀粉样蛋白A(SAA)、中性粒细胞百分比(Neu%)、白介素-6(IL-6)、白细胞计数(WBc)水平均显著下降(P均cAP患者具有显著的临床治疗成效,能对患者肺部感染进行有效把控,同时也能够缓解患者畏寒发热、咳嗽、咳痰等不适状况,且没有明显不良反应出现,能够在临床中进行推广应用。

关键词：社区获得性肺炎重连口服液疗效炎症指标

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Serological Targeted Analysis of an ITIH4 Peptide Isoform: A Preterm Birth Biomarker and Its Associated SNP Implications

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journal of Genetics and Genomics 2015年第9期42卷 507-510页

作者： Zhou Tan Zhongkai Hu Emily Y.cai cantas Alev Ting yang Zhen Li joyce Sung Yasser Yehia El-Sayed Gary M.Shaw David K.Stevenson Atul j.Butte Guojun Sheng Karl G.Sylvester Harvey j.cohen Xuefeng B.Ling Institute of Developmental and Regenerative Biology Hangzhou Normal University Department of Surgery Stanford University Lab for Early Embryogenesis RIKEN Center for Developmental Biology Department of Obstetrics and Gynecology Stanford University Department of Pediatrics Stanford University Stanford

Over 11% of all pregnancies in the US result in preterm birth, greatly contributing to perinatal morbidity and mortality （Goldenberg and Rouse, 1998）. Preterm birth etiologies remain largely unknown, and effective prevention methods have yet to be developed. The use of biofluid （e.g., serum or urine） for the analysis of the naturally occurring peptidome （MW 〈 4000） as a source of biomarkers has been reported for different diseases （Villanueva et al., 2006; Ling et al., 2010a, 2010b, 2010c, 2011）. Mass spectrometry-based profiling of naturally occurring peptides can provide an extensive in- ventory of serum peptides derived from either high-abundant endogenous circulating proteins or cell and tissue proteins （Liotta and Petricoin, 2006）.

关键词： Serological Targeted Analysis of an ITIH4 Peptide Isoform A Preterm Birth Biomarker and Its Associated SNP Implications SNP

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