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Hydroxyl-terminated Polyethylenes Bearing Functional Side Groups:Facile Synthesis and Their Properties

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Chinese Journal of Polymer Science 2021年第8期39卷 994-1003,I0006页

作者： Wan-Bin Zhang Jie Luo Yan-Meng Wang Xiu-Zhong zhu ce Zhang Jing Liu Mei-Le Ni Guang-Hua Zhang Shaanxi Collaborative Innovation center of Industrial Auxiliary Chemistry and Technology Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Chemical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science&TechnologyXi'an 710021China School of Light Industry and Engineering Qi Lu University of Technology(Shandong Academy of Sciences)Jinan 250353China

A series of hydroxyl-terminated polyethylenes(HTPE)bearing various functional side groups(***,ester and butane groups)were synthesized by the combination of ring opening metathesis polymerization(ROMP)and visible light photocatalytic thiol-ene *** products are named as a,w-dihydroxyl-polyllpropionyloxythio)methinetrimethylene](HTPECarboxy),a,w dihydroxy-poly(methylpropionatethio)methinetrimethylene](HTPEeser)and a,wdihydroxyl-poly[(butylthio)methinetrimethylene](HTPEbutane)*** investigation of ROMP indicated that the molecular weight of resultant hydroxy-terminated polybutadiene(HTPB)can be tailored by varying the feed ratios of monomer to chain transfer agent(CTA).The exploration of the photocatalytic thiol-ene reaction between HTPB precursor and methyl-3-mercaptopropionate revealed that blue light as well as oxygen accelerated the reaction.1H-NMR and 13C-NMR results verified all the double bonds in HTPB can be modified,and the main chain of resultant polymer can be considered as ***,relationship between the structure of side groups and the thermal properties of functional PEs was *** the results suggested that the Tg was in the order of HTPEbuanece of active hydroxyl end *** can serve as a plasticizer for PVC which can enhance the ductilityt of PVC without obviously sacrificing strength.

关键词： Polyethylene Ring-opening metathesis polymerization Thiol-ene reaction Polybutadiene Structure property relationships

Molten salt as ultrastrong polar solvent enables the most straightforward pyrolysis towards highly efficient and stable single-atom electrocatalyst

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Journal of Energy Chemistry 2021年第3期30卷 519-527页

作者： Nannan Li Wei Liu Chao zhu ce Hao Jingya Guo Hongyu Jing Jinwen Hu Cuncun Xin Danyang Wu Yantao Shi State Key Laboratory of Fine Chemicals Department of ChemistrySchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina SEU-FEI Nano-Pico center Key Laboratory of MEMS of Ministry of EducationCollaborative Innovation Center for Micro/Nano FabricationDevice and SystemSoutheast University2 No.4 PailouNanjing 210096JiangsuChina

Currently,pyrolysis as the most widely used method still has some key issues not well resolved for synthesis of carbon-supported single-atom catalysts(C-SACs),e.g.,the sintering of metal atoms at high temperature as well as the high cost and complicated preparations of *** this report,molten salts are demonstrated to be marvellous medium for preparation of C-SACs by pyrolysis of small molecular precursors(ionic liquid).The ultrastrong polarity on one hand establishes robust interaction with precursor and enables better carbonization,resulting in largely enhanced *** the other hand,the aggregation of metal atoms is effectively refrained while no nanoparticle or cluster is *** this strategy,a C-SAC with atomically dispersed Fe-N_(4) sites and a high specific area over 2000 m^(2) g^(-1) is obtained,which illustrates high ORR activity in both acid and alkaline ***,this SAC exhibits superior methanol tolerance and stability after acid soaking at 85℃ for 48 *** is believed that the molten-salts-assisted pyrolysis can be developed into a routine strategy as it not only can largely simply the synthesis of C-SACs,but also can be extended to prepare other types of SACs.

关键词： Ultrastrong polar solvent Molten salts one-pot pyrolysis Carbon-supported single atom catalysts Oxygen reduction reaction

Asian Horseshoe Crab Bycatch in Intertidal Zones of the Northern Beibu Gulf:Suggestions for Conservation Management

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Journal of Ocean University of China 2022年第3期21卷 611-621页

作者： WANG Chun-Chieh CHEN Ruifang YANG Xin WEN Yulong KUANG Yang ZHANG ce zhu Junhua KWAN Kit Yue Guangxi Key Laboratory of Marine Environmental Science Guangxi Beibu Gulf Marine Research CenterGuangxi Academy of SciencesNanning530007China Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation College of Marine SciencesBeibu Gulf UniversityQinzhou535011China

Bycatch poses a severe challenge to global fishery *** studies have focused on marine megafauna bycatch,research on relevant issues regarding invertebrates is limited,particularly for the threatened horseshoe *** this study,the distribution of fishing gears and the bycatch intensity of Asian horseshoe crabs in the intertidal zones of the northern Beibu Gulf that harbors the most abundant juvenile Asian horseshoe crabs populations in China were *** intertidal nursery habitats for Tachypleus tridentatus and Carcinoscorpius rotundicauda were surveyed from May to July in 2021.A transect that crossed the tidal creeks and tidal flats between the high tide embankment/vegetation and low tide line of a given habitat was surveyed during the ebb *** type,number,and GPS of fishing gears were recorded when sighted,and the number and prosomal width of each horseshoe crab species were *** intensities differed among habitats,ranging from 0.3 to 18.4 and 1.2 to 22.7 individuals per kilometer of transect for *** and ***,*** the three identified fishing gear types,ground cages and stick net sets caused a stronger bycatch pressure on these two *** *** bycatch and *** bycatch were large individuals in late juvenile and adult ***,the ground cages and stick net sets along/near the tidal creeks,mangrove fringe,and low tide line should be regulated and removed to ensure the functionality of the intertidal zone as the spawning corridor and nursery habitat of Asian horseshoe crabs.

关键词： Tachypleus tridentatus Carcinoscorpius rotundicauda ground cage stick net tidal creek mangrove low tide line spawning corridor

Recent progress of Pd/zeolite as passive NO_(x) adsorber: Adsorption chemistry, structure-performance relationships, challenges and prospects

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Chinese Chemical Letters 2022年第3期33卷 1169-1179页

作者： ce Bian Dan Li Qian Liu Shoute Zhang Lei Pang zhu Luo Yanbing Guo Zhen Chen Tao Li Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China DongFeng Trucks R&D center Wuhan 430056China Key Laboratory of Pesticide and Chemical Biology of Ministry of Education Institute of Environmental and Applied ChemistryCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Due to the technology limitation and inferior deNO_(x) efficiency of urea selective catalytic reduction (SCR) catalysts at low temperatures, passive NO_(x) adsorber (PNA) for decrease of NO_(x), CO and hydrocarbons (HCs) during “cold start” of vehicles was proposed to meet the further tighten NO_(x) emission regulations in future. Among them, Pd modified zeolite PNA materials have received more attention because of their excellent NO_(x) storage capacity, anti-poisoning and hydrothermal stability and since Pd/zeolite PNA was proposed, a variety of advanced characterization methods have been applied to investigate its adsorption behavior and structure-performance relationship. The comprehension of the active sites and adsorption chemistry of Pd/zeolite PNA was also significantly improved. However, there are few reviews that systematically summarize the recent progress and application challenges in atomic-level understanding of this material. In this review, we summarized the latest research progress of Pd/zeolite PNA, including active adsorption sites, adsorption mechanism, material physicochemical properties, preparation methods, storage and release performance and structure-performance relationships. In addition, the deactivation challenges faced by Pd/zeolite PNA in practical applications, such as chemical poisoning, high temperature hydrothermal aging deactivation, etc., were also discussed at the micro-level, and some possible effective countermeasures are given. Besides, some possible improvements and research hotspots were put forward, which could be helpful for designing and constructing more efficient PNA materials for meeting the ultra-low NO_(x) emission regulation in the future.

关键词： Emission control Pd/zeolite Passive NO_(x)adsorber NO_(x)storage Cold start

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妊娠子宫破裂的超声诊断价值

中国医药导报 2008年第27期5卷 77-78页

作者：陈建成吴建伟李树兴柯亮朱策均梁美艳深圳市观澜人民医院广东深圳518110

目的:探讨妊娠子宫破裂的超声影像学特点及诊断价值。方法:回顾性分析我院收治的12例妊娠子宫破裂患者的资料。结果:本组12例病例中,妊娠子宫完全性破裂8例,妊娠子宫不完全性破裂3例,超声误诊1例,超声诊断符合率为91.7%,所有病例均经手... 详细信息

目的:探讨妊娠子宫破裂的超声影像学特点及诊断价值。方法:回顾性分析我院收治的12例妊娠子宫破裂患者的资料。结果:本组12例病例中,妊娠子宫完全性破裂8例,妊娠子宫不完全性破裂3例,超声误诊1例,超声诊断符合率为91.7%,所有病例均经手术证实。结论:超声作为一种无创伤性检查方法,对妊娠子宫破裂的诊断有较高的特异性,在妊娠子宫破裂的病例中,应用超声可明确有无穿孔、穿孔的部位、大小以及腹腔积液的情况,对临床诊断及治疗提供十分重要的指导价值。

关键词：妊娠子宫破裂超声诊断

Identification of key genes controlling cancer stem cell characteristics in gastric cancer

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World Journal of Gastrointestinal Surgery 2020年第11期12卷 442-459页

作者： Chao Huang ce-Gui Hu Zhi-Kun Ning Jun Huang Zheng-Ming zhu Department of Gastrointestinal Surgery The Second Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Self-renewal of gastric cancer stem cells(GCSCs)is considered to be the underlying cause of the metastasis,drug resistance,and recurrence of gastric cancer(GC).AIM To characterize the expression of stem cell-related genes in *** RNA sequencing results and clinical data for gastric adenoma and adenocarcinoma samples were obtained from The Cancer Genome Atlas database,and the results of the GC mRNA expression-based stemness index(mRNAsi)were *** gene coexpression network analysis was then used to find modules of interest and their key *** analysis of key genes was performed using the online tool Kaplan-Meier Plotter,and the online database Oncomine was used to assess the expression of key genes in *** mRNAsi was significantly upregulated in GC tissues compared to normal gastric tissues(PceNPF,TTK,KIF4 A,SGOL2,PLK4,XRCC2,a n d C1 orf112)were identified in the brown *** functional and pathway enrichment analyses showed that the key genes were significantly enriched in the spindle cellular component,the sister chromatid segregation biological process,the motor activity molecular function,and the cell cycle and homologous recombination *** analysis and Oncomine analysis revealed that the prognosis of patients with GC and the expression of three genes(RAD54 L,TPX2,and XRCC2)were consistently *** Sixteen key genes are primarily associated with stem cell self-renewal and cell proliferation ***54 L,TPX2,and XRCC2 are the most likely therapeutic targets for inhibiting the stemness characteristics of GC cells.

关键词： Gastric cancer Cancer stem cell Key gene The Cancer Genome Atlas database Weighted gene coexpression network analysis mRNA expression-based stemness index

A loss-of-function mutant allele of a glycosyl hydrolase gene has been co-opted for seed weight control during soybean domestication

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Journal of Integrative Plant Biology 2023年第11期65卷 2469-2489页

作者： Siming Wei Bin Yong Hongwei Jiang Zhenghong An Yan Wang Bingbing Li ce Yang Weiwei zhu Qingshan Chen Chaoying He State Key Laboratory of Plant Diversity and Specialty Crops/State Key Laboratory of Systematic and Evolutionary Botany Institute of Botanythe Chinese Academy of SciencesBeijing 100093China China National Botanical Garden Beijing 100093China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China College of Agriculture Northeast Agricultural UniversityHarbin 150030China Jilin Academy of Agricultural Sciences Changchun 130022China The Innovative Academy of Seed Design the Chinese Academy of SciencesBeijing 100101China

The resultant DNA from loss-of-function mutation can be recruited in biological evolution and ***,we present such a rare and potential case of“to gain by loss”as a neomorphic mutation during soybean domestication for increasing seed *** a population derived from a chromosome segment substitution line of Glycine max(SN14)and Glycine soja(ZYD06),a quantitative trait locus(QTL)of 100-seed weight(q HSW)was mapped on chromosome 11,corresponding to a truncatedβ-1,3-glucosidase(βGlu)*** novel gene hsw results from a 14-bp deletion,causing a frameshift mutation and a premature stop codon in theβ*** contrast to HSW,the hsw completely lostβGlu activity and function but acquired a novel function to promote cell expansion,thus increasing seed *** hsw instead of HSW produced large soybean seeds,and surprisingly,truncating hsw via gene editing further increased the seed *** further found that the core 21-aa peptide of hsw and its variants acted as a promoter of seed *** variation in these transgenic soybean lines substantiated the integration hsw into cell and seed size ***,the hsw allele underwent selection and expansion during soybean domestication and *** work cloned a likely domesticated QTL controlling soybean seed weight,revealed a novel genetic variation and mechanism in soybean domestication,and provided new insight into crop domestication and breeding,and plant evolution.

关键词： domestication frameshift mutation QTL seed weight soybean to gain by loss

Effect of Ag on High-Temperature Oxidation Behavior of Mg-6.5Gd-5.6Y-0.1Nd-0.01ce-0.4Zr Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第11期37卷 1843-1857页

作者： Shuang Guo Tianyu Liu Tianjiao Luo Yingju Li Xiaohui Feng Qiuyan Huang ce Zheng Cheng zhu Yuansheng Yang Weirong Li Feng Li School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China Institute of Metal Research Chinese Academy of ScienceShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China Shandong Provincial Key Laboratory of High Strength Lightweight Metallic Materials Qilu University of Technology(Shandong Academy of Sciences)Jinan250014China Dongguan EONTEC Co.Ltd Guangdong523662China

In this paper,the isothermal oxidation experiments were used to study the effect of Ag on the high-temperature oxidation behavior of Mg-6.5Gd-5.6Y-0.1Nd-0.01ce-0.4Zr(wt%)alloy oxidized at 350℃,400℃ and 450℃ for 120 *** results show that the oxidation weight gain of the alloy mainly occurs in the early oxidation stage(0-20 h).This reason attributes to the lack of protective oxide film and the rapid inward diffusion of oxygen through the macroscopic defects of the incomplete oxide *** dense oxide films such as Y_(2)O_(3),Gd_(2)O_(3),and ZrO2 form,they hinder the inward transport of oxygen ions and improve the high-temperature oxidation resistance of the *** addition,the role of the Ag element at three temperatures is *** addition of Ag mainly promotes the formation of eutectic phases such as Mg3Gd,Mg24Y5,and Ag2Gd,which reduces the content of Gd and Y elements in the alloy matrix,resulting in a decrease in the diffusion rate of Gd and Y elements during the oxidation process at 350℃ and 400℃,and weakens the oxidation resistance of Ag-containing ***,in the oxidation experiment at 450℃,a large amount of eutectic phase is solid dissolved into the matrix,reducing the difference in element *** this time,it is detected that the Ag element promoted the outward diffusion of Gd and Y elements,accelerating the formation of the oxide *** oxidation resistance of Ag-containing alloys is improved.

关键词： Magnesium alloy High-temperature oxidation Thermogravimetric analysis Gibbs free energy Oxide film Oxidation resistance

基于LabVIEW的动车螺栓联接状态监测系统

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变频器世界 2024年第8期27卷 102-108页

作者：王秋实张隽朱册李俊男柳子轩洪鑫陈春桥王珑皓吉林铁道职业技术学院吉林省吉林市132000

螺栓的紧固状态是动车各结构健康状态的重要指标,一旦螺栓发生松动,将引起某个结构的故障或损坏,更有甚者威胁到动车组安全平稳运行,因此对螺栓联接状态的监测显得尤为重要。本文将螺栓的转动表示为凸轮的转动,并利用一种等强度弹性元... 详细信息

螺栓的紧固状态是动车各结构健康状态的重要指标,一旦螺栓发生松动,将引起某个结构的故障或损坏,更有甚者威胁到动车组安全平稳运行,因此对螺栓联接状态的监测显得尤为重要。本文将螺栓的转动表示为凸轮的转动,并利用一种等强度弹性元件将螺栓的转动表示为弹性元件的应变变化,从而实现螺栓转角的检测。为了得到转角与应变之间的对应关系,本文设计了相应的螺栓转角测量实验,并用LabVIEW编写程序进行数据的处理。基于实验结果,设计了一种级联式易拆装传感器结构,并对传感器的静态特性进行了测试,测试结果表明该传感器的精度为6.679%,灵敏度为9.2363μ/,该传感器性能优越。

关键词：螺栓转角 LabVIEW 应变传感器监测系统