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Rare Metals 2024年第9期43卷 4198-4221页

作者： Miao Ma Li-Xiao shen Jing Liu bin Xu Yun-Long Zhang Lei Zhao Zhen-Bo Wang School of Chemistry and Chemical Engineering Harbin Instituteof Technology College of Environmental and Chemical Engineering YanshanUniversity Unipower Hydrogen Technology (Jiangsu) Corporation

Proton exchange membrane fuel cells(PEMFCs) have been identified as a highly promising means of achieving sustainable energy conversion. A crucial factor in enhancing the performance of PEMFCs for further potential energy applications is the advancement in the field of catalyst engineering that has led to remarkable performance enhancement in facilitating the oxygen reduction reaction(ORR). Subsequently, it is important to acknowledge that the techniques used in preparation of membrane electrode assemblies(MEAs), the vital constituents of PEMFCs, also possess direct and critical influence on exhibiting the full catalytic activity of meticulously crafted catalysts. Here, a succinct summary of the most recent advancements in Pt catalysts for ORR was offered and their underly catalytic mechanism were discussed. Then, both laboratory-scale and industrial-scale MEA fabrication techniques of Pt catalysts were summarized. Furthermore, a detailed analysis of the connections between materials, process, and performance in MEA fabrication was presented in order to facilitate the development of optimal catalyst layers.

关键词： MEA fabrication techniques Membrane electrode assemblies Oxygen reduction reaction Pt catalysts

Bilayer Compounded Polytetrafluoroethylene Membrane for Enhanced Oil-Water Emulsion Separation

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Chinese Journal of Polymer Science 2024年第6期42卷 838-850页

作者： Yu-Liang Yang Tai-Ran Zhang Yan-Ting Han Shao-Yun Guo Qin-Gong Rong Jia-bin shen State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversitySichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing TechnologyChengdu610065China West China Hospital/West China School of Nursing Sichuan UniversityChengdu610041China Shandong Senrong New Materials Co. Ltd.Zibo256401China

In order to achieve efficient and durable oil-water emulsion separation,the membranes possessing high separation efficiency and mechanical strength attract extensive attention and are in great *** present study,a kind of polytetrafluoroethylene(PTFE)-based bilayer membrane was fabricated by electrospinning fibrous PTFE(fPTFE)on an expanded PTFE(ePTFE)*** morphological observation revealed that the fibrous structure of the fPTFE layer could be tailored by controlling the formulation of spinning *** addition of appropriate polyoxyethylene(PEO)would make the fibers in the fPTFE layer finer and more *** a result,the compounded membrane exhibited a small pore size of approximately 1.25µm and a substantial porosity nearing 80%.This led to super-hydrophobicity,characterized by a high water contact angle(WCA)of 149.8°,and facilitated rapid oil *** water-in-oil emulsion separation experiment further confirmed that the compounded membrane not only had a high separation efficiency closing 100%,but such an outstanding separation capacity could be largely retained,either through multiple cycles of use or through strong acid(pH=1),strong alkali(pH=12),or high-temperature(100°C)***,the mechanical behavior of the bilayer membrane was basically contributed by that of each layer in terms of their volume *** significantly,the poor creep resistance of fPTFE layer was suppressed by compounding with ePTFE ***,this study has laid the groundwork for a novel approach to create PTFE-based compounded membranes with exceptional overall characteristics,showing promise for applications in the realm of emulsion separation.

关键词： ePTFE Electrospinning membrane Bilayer compounding Emulsion separation

Osteology of Leptobrachella bijie(Anura,Megophryidae)

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Asian Herpetological Research 2024年第2期15卷 90-103页

作者： Wei LI Meihua ZHANG Zhonghao LUO Jing LIU Tuo shen Bo CHEN Haijun SU bin WANG College of Forestry Guizhou UniversityGuiyang 550025GuizhouChina Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina

The Asian leaf litter toad genus Leptobrachella contains more than 100 species widely distributed in southwestern ***,the systematic profiles of this group remain *** morphology is important for taxonomic and phylogenetic ***,few studies have focused on the osteology of the ***,we comprehensively described the osteological features of a representative species *** based on micro-CT scanning and double-staining *** results show that the skull of adult *** is well-ossified,exhibiting sexual dimorphism and minimal intraspecific *** skull length is slightly greater than the width,with the maxilla slightly overlapping with the *** nasal connects with the sphenethmoid in males,but only part or not connects with the sphenethmoid in *** transverse processes of the sacrum are robust and symmetrically butterfly-shaped,and the presacral vertebrae are *** pectoral girdle is *** phalangeal formula is 2-2-3-3 for the hand,and 2-2-3-4-3 for the *** study provides the first detailed and comprehensive osteological accounts of the genus Leptobrachella.

关键词： sexual dimorphism skeleton taxonomy

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复合固体推进剂颗粒脱湿损伤参数反演

推进技术 2016年第10期37卷 1977-1983页

作者：职世君曹付齐申志彬邢国强曹军伟中国空空导弹研究院河南洛阳471000 国防科技大学航天科学与工程学院湖南长沙410073

为确定复合固体推进剂颗粒脱湿损伤参数,采用分子动力学方法建立了复合固体推进剂颗粒夹杂模型,根据Surface-based cohesive方法,在高氯酸铵(AP)颗粒与基体之间的界面处设置接触损伤,对复合固体推进剂的细观损伤过程进行数值仿真计算。... 详细信息

为确定复合固体推进剂颗粒脱湿损伤参数,采用分子动力学方法建立了复合固体推进剂颗粒夹杂模型,根据Surface-based cohesive方法,在高氯酸铵(AP)颗粒与基体之间的界面处设置接触损伤,对复合固体推进剂的细观损伤过程进行数值仿真计算。将数值仿真得到的应力-应变曲线与试验曲线进行对比,建立颗粒脱湿损伤参数的优化目标函数,通过分步迭代计算,对颗粒脱湿损伤参数进行反演识别。结果表明:根据反演参数计算复合固体推进剂细观损伤过程,颗粒夹杂模型表现出的宏观应力-应变关系与试验结果吻合良好,说明双折线损伤模型可以近似表征复合固体推进剂的脱湿损伤。

关键词：固体推进剂细观力学界面损伤数值模拟参数反演

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番薯块根化学成分研究

中药材 2012年第6期35卷 913-917页

作者：尹永芹沈志滨孔令义广东药学院中药学院广东广州510006 中国药科大学天然药物化学教研室江苏南京210009

目的:研究番薯块根的化学成分。方法:95%乙醇提取回收溶剂后以氯仿萃取,萃取部位经多种层析方法分离;结合理化性质和波谱方法进行结构鉴定。结果:分离并鉴定了6个化合物,分别为:Batatinoside I(1)、枸橼苦素(2)、咖啡酸十八烷酯(3)、乙... 详细信息

目的:研究番薯块根的化学成分。方法:95%乙醇提取回收溶剂后以氯仿萃取,萃取部位经多种层析方法分离;结合理化性质和波谱方法进行结构鉴定。结果:分离并鉴定了6个化合物,分别为:Batatinoside I(1)、枸橼苦素(2)、咖啡酸十八烷酯(3)、乙酰-β-香树醇(4)、咖啡酸(5)、东莨菪素(6)。结论:其中,化合物1为结构新颖的树脂糖苷类化合物,并首次从番薯中分离得到。

关键词：番薯属番薯化学成分树脂糖苷

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巴西甘薯叶化学成分研究

中药材 2008年第10期31卷 1501-1503页

作者：尹永芹沈志滨孔令义广东药学院中药化学与分析教研室广东广州510006 中国药科大学天然药物化学教研室江苏南京210038

目的：研究巴西甘薯叶的化学成分。方法：巴西甘薯叶乙醇提取物经石油醚、乙酸乙酯、正丁醇萃取，其中乙酸乙酯、正丁醇萃取部位用硅胶柱色谱、Sephadex LH-20凝胶柱色谱等方法，分离得到4个化合物，经理化性质和波谱数据鉴定结构。结... 详细信息

目的：研究巴西甘薯叶的化学成分。方法：巴西甘薯叶乙醇提取物经石油醚、乙酸乙酯、正丁醇萃取，其中乙酸乙酯、正丁醇萃取部位用硅胶柱色谱、Sephadex LH-20凝胶柱色谱等方法，分离得到4个化合物，经理化性质和波谱数据鉴定结构。结果：从巴西甘薯叶中分离鉴定4个化合物，分别为枸橼苦素（1）、咖啡酸（2）、3，4-二咖啡酰基奎宁酸（3）、1，2，3，4-四氢-β-咔啉-3-羧酸（4）。结论：化合物1～4均为首次从该植物中分离得到。

关键词：甘薯化学成分

移动荷载作用下非局部地基梁动力响应分析的有限元法

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计算力学学报 2016年第3期33卷 301-305页

作者：姜人伟申志彬张亚辉国防科学技术大学航天科学与工程学院长沙410073 大连理工大学工业装备结构分析国家重点实验室大连116023

基于非局部地基理论,推导了移动荷载作用下非局部地基梁动力响应问题的有限元解,分别讨论了地基的非局部参数、刚度、阻尼系数以及移动荷载速度对非局部地基梁动力响应的影响,并比较了非局部结果与局部结果的差异。结果表明,地基的非局... 详细信息

基于非局部地基理论,推导了移动荷载作用下非局部地基梁动力响应问题的有限元解,分别讨论了地基的非局部参数、刚度、阻尼系数以及移动荷载速度对非局部地基梁动力响应的影响,并比较了非局部结果与局部结果的差异。结果表明,地基的非局部参数、刚度和阻尼是地基梁的动力响应的主要影响参数,地基梁最大响应及其发生的时刻与移动荷载速度有关。研究成果可为轨道地基系统设计提供参考。

关键词：移动荷载非局部地基有限元动力响应轨道地基系统

Review of the field environmental sensing methods based on multi-sensor information fusion technology

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 1-13页

作者： Yuanyuan Zhang bin Zhang Cheng shen Haolu Liu Jicheng Huang Kunpeng Tian Zhong Tang Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China School of Mechanical Engineering Southeast UniversityNanjing 211189China School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Field environmental sensing can acquire real-time environmental information,which will be applied to field operation,through the fusion of multiple ***-sensor fusion refers to the fusion of information obtained from multiple sensors using more advanced data processing *** main objective of applying this technology in field environment perception is to acquire real-time environmental information,making agricultural mechanical devices operate better in complex farmland environment with stronger sensing ability and operational *** this paper,the characteristics of sensors are studied to clarify the advantages and existing problems of each type of sensors and point out that multiple sensors can be introduced to compensate for the information ***,the mainstream information fusion types at present are *** characteristics,advantages and disadvantages of different fusion methods are *** important studies and applications related to multi-sensor information fusion technology published at home and abroad are ***,the existing problems in the field environment sensing at present are summarized and the prospect for future of sensors precise sensing,multi-dimensional fusion strategies,discrepancies in sensor fusion and agricultural information processing are proposed in hope of providing reference for the deeper development of smart agriculture.

关键词： multi-sensor information fusion field environmental sensing fusion methods smart agriculture

SUPER WOMAN 2(SPW2)maintains organ identity in spikelets by inhibiting the expression of floral homeotic genes OsMADS3,OsMADS58,OsMADS13,and DROOPING LEAF

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Journal of Integrative Agriculture 2024年第1期23卷 59-76页

作者： Hui Zhuang Jinsong Lan Qiuni Yang Xiaoyu Zhao Yuhuan Li Jingya zhi Yalin shen GuanghuaHe Yunfeng Li Rice Research Institute Key Laboratory of Application and Safety Control of Genetically Modified CropsAcademy of Agricultural SciencesSouthwest UniversityChongqing 400715China

Flower organ identity in rice is mainly determined by the A-,B-,C-and E-class genes,with the majority encoding MADS-box transcription ***,few studies have investigated how the expression of these floral organ identity genes is regulated during flower *** this study,we identified a gene named SUPER WOMAN 2(SPW2),which is necessary for spikelet/floret development in rice by participating in the regulation of the expression of pistil identity genes such as OsMADS3,OsMADS13,OsMADS58 and *** the spw2 mutant,ectopic stigma/ovary-like tissues were observed in the non-pistil organs,including sterile lemma,lemma,palea,lodicule,and stamen,suggesting that the identities of these organs were severely affected by mutations in ***2 was shown to encode a plant-specific EMF1-like protein that is involved in H3K27me3 modification as an important component of the PRC2 *** analysis showed that the SPW2 mutation led to the ectopic expression of OsMADS3,OsMADS13,OsMADS58,and DL in non-pistil organs of the *** ChIP-qPCR results showed significant reductions in the levels of H3K27me3 modification on the chromatin of these ***,we demonstrated that SPW2 can mediate the process of H3K27me3 modification of pistil-related genes to regulate their expression in non-pistil organs of spikelets in *** results of this study expand our understanding of the molecular mechanism by which SPW2 regulates floral organ identity genes through epigenetic regulation.

关键词： rice(Oryza sativa) spikelet organ identity H3K27me3

Simultaneous Bulk-and Surface-initiated Living Polymerization Studied with a Heterogeneous Stochastic Reaction Model

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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： Jia-Shu Ma zhi-Ning Huang Jia-Hao Li Bang-Ping Jiang Yan-Da Liao Shi-Chen Ji Xing-Can shen State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Computer Science and Engineering&School of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization