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Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： Li-Rong Xiao Chen Chen Shuo wang Zi-Yin Dai Hideo Kimura Cui Ni Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo Wei Du xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with Ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements

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陕西关中地区剪应力分布及近期地震趋势分析

西北地震学报 2000年第4期22卷 414-418页

作者：王亚秀李博李少睿陕西省地震局，陕西西安 710068

根据峰值速度与构造环境剪应力的关系 ,利用西安数字化地震台网记录到的小震资料 ,初步计算了陕西关中地区的剪应力分布 .结果表明 ,关中中部的剪应力值较低 ,近期发生较大地震的可能性较小 .但关中北部的韩城、西部的宝鸡—千阳、东部... 详细信息

根据峰值速度与构造环境剪应力的关系 ,利用西安数字化地震台网记录到的小震资料 ,初步计算了陕西关中地区的剪应力分布 .结果表明 ,关中中部的剪应力值较低 ,近期发生较大地震的可能性较小 .但关中北部的韩城、西部的宝鸡—千阳、东部的大荔—华阴一带剪应力值较高 ,存在发生 5级左右地震的背景 .

关键词：数字化地震台网地震趋势剪应力分布构造环境

中国农地经营规模对农业劳动生产率的影响及其区域差异

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自然资源学报 2017年第4期32卷 539-552页

作者：王亚辉李秀彬辛良杰谈明洪李薇中国科学院地理科学与资源研究所陆地表层格局与模拟重点实验室北京100101 中国科学院大学北京100049

农业劳动生产率偏低依旧是中国农业发展的瓶颈,它关系着农民增收和农业发展,提高劳动生产率迫在眉睫。在土地规模不断集中已成为顶层设计基本共识的前提下,理清农地经营规模与劳动生产率之间的关系尤为重要。基于此,论文利用2000—2013... 详细信息

农业劳动生产率偏低依旧是中国农业发展的瓶颈,它关系着农民增收和农业发展,提高劳动生产率迫在眉睫。在土地规模不断集中已成为顶层设计基本共识的前提下,理清农地经营规模与劳动生产率之间的关系尤为重要。基于此,论文利用2000—2013年中国大陆31个省份的面板数据,通过理论推断与实证检验,对劳动生产率与农地经营规模的关系进行了定量分析。结果表明:从全国、不同地貌及三大经济带来看,劳动生产率与农地经营规模之间均存在鲜明的"倒L型"关系,即初始阶段,扩大农地经营规模能显著提高劳动生产率,但区域间差异明显,后期劳动生产率会稳定在某一状态。当前,农地规模远小于人均农地的最优经营规模,农地规模的集中是提高劳动生产率的重要举措,推进发展适度规模经营的政策仍有较大的操作空间。政府需要做的是,降低土地流转的交易成本,推动实现多种形式的农地适度规模经营,并兼顾不同区域的差异。

关键词：劳动生产率农地经营规模平衡面板土地流转

Clinicopathological differences between patients with schistosomal appendicitis and non schistosomal appendicitis:A retrospectively study of past ten years

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World Journal of Clinical Cases 2025年第2期13卷 24-32页

作者： Xiao-Yi wang yao Hao Zi-Jian wang xiu-Liang Xu Jiang-Hua yang Department of Infectious Diseases The First Affiliated of Wannan Medical CollegeWuhu 241001Anhui ProvinceChina

BACKGROUND Chronic schistosomiasis causes multiple organ and multiple system diseases,especially the digestive *** eggs are mainly deposited in the stomach,liver and colorectal,but a few eggs are deposited in the appendix and cause *** present,there are few studies on schistosomal *** To explore the differences in epidemiological,clinical and pathological characteristics between schistosomal appendicitis and non-schistosomal appendicitis over the past decade in order to assess the impact of schistosomiasis on *** The differences of general data,clinical data and laboratory examination data of patients with appendicitis from October 2013 to October 2023 were retrospectively *** patients were divided into two groups for *** were 136 patients in schistosomal appendicitis group and 5418 patients in non-schistosomal appendicitis *** Schistosomal appendicitis accounted for 2.45%of all patients with appendicitis,and the annual proportion in the past decade was 2.2%,2.9%,1.8%,1.9%,3.4%,3.1%,1.9%,1.6%,3%,2.6%,*** prevalence of schistosomal appendicitis was middle-aged and elderly males,with an average age of 61.73±15.335 *** main population of non-schistosomal appendicitis was middle-aged men,with an average age of 35.8±24.013 years(P<0.001).The distribution of pathological types of appendicitis was different between the two groups(P<0.001).The incidence of acute suppurative appendicitis in non-schistosomal appendicitis was higher than that in schistosomal appendicitis[odds ratio(OR)=0.504;95%confidence interval(CI):0.349-0.728;P<0.001].The proportion of acute attack of chronic appendicitis in schistosomal appendicitis was higher than that in non-schistosomal appendicitis(OR=2.614;95%CI:1.815-3.763;P<0.001).The proportion of schistosomal appendicitis patients complicated with colorectal cancer was higher than that of nonschistosomal appendicitis patients(OR=5.087;95%CI:1.427-

关键词： Schistosomal appendicitis Schistosomiasis Appendix Colorectal cancer Clinicopathological characteristics

乌梁素海及其周边水体222 Rn的时空分布特征及其指示意义

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东北师大学报（自然科学版） 2023年第4期55卷 134-141页

作者：余楚吴利杰张翼龙王占川王秀雅郭娇中国地质科学院水文地质环境地质研究所河北石家庄050061 自然资源部地下水科学与工程重点实验室河北正定050803 河北地质大学水资源与环境学院河北石家庄050031

对内蒙古自治区乌梁素海湖泊及其周边河渠、地下水中放射性同位素氡(222 Rn)含量的时空分布特征进行了调查分析.结果表明:乌梁素海非灌溉期(2021年9月上旬)湖水、出入湖河渠水、近湖岸地下水的222 Rn活度均小于灌溉期(2020年10月下旬),... 详细信息

对内蒙古自治区乌梁素海湖泊及其周边河渠、地下水中放射性同位素氡(222 Rn)含量的时空分布特征进行了调查分析.结果表明:乌梁素海非灌溉期(2021年9月上旬)湖水、出入湖河渠水、近湖岸地下水的222 Rn活度均小于灌溉期(2020年10月下旬),非灌溉期湖水的222 Rn活度约为灌溉期的39%,表明灌溉入渗、排水过程改变了区域地下水水动力条件,加速了区域地下水的循环流动,增大了水循环系统中的222 Rn活度;河湖222 Rn活度的时空差异性显著,灌溉期湖水222 Rn在总排干入湖区偏大,表明总排干退水是湖水222 Rn的主要源项.非灌溉期湖水222 Rn活度(129.72~194.59 Bq/m^(3))和退水渠内湖水222 Rn活度(277.25 Bq/m^(3))均大于总排干内湖水222 Rn活度(110.72 Bq/m^(3)),指示地下水对湖水存在一定的补给;非灌溉期西南岸地下水222 Rn活度仅为区域平均值的47.5%,指示该地区存在湖水的侧渗补给,稀释了地下水中的222 Rn.乌梁素海接受地下水的补给,但补给水量不大,在灌溉期总排干入湖水量对湖体水环境起主要的控制作用,在非灌溉期地下水对湖体水环境的影响程度可能要高于灌溉期.

关键词：乌梁素海氡同位素湖水地下水补排关系

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu Hao-Yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie Xu ya-Qi Li Zhi-Zhen Ren Liang wang Wei-Chang Hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

家蝇肽聚糖识别蛋白(PGRP-SA)的克隆表达及细菌结合研究

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生物技术通报 2016年第8期32卷 145-151页

作者：罗嫚王宇胡亚修江帆王涛彭建尚小丽吴建伟贵州医科大学寄生虫学教研室贵阳550004 贵州省疾病预防控制中心贵阳550004

对家蝇PGRP-SA基因进行克隆表达以及研究其重组蛋白与细菌结合能力。从构建的家蝇(Musca domestica)幼虫cDNA质粒文库中筛选到PGRP-SA基因,以cDNA质粒为模板设计引物,通过PCR扩增,获得PGRP-SA基因完整编码序列。运用生物信息学方法对该... 详细信息

对家蝇PGRP-SA基因进行克隆表达以及研究其重组蛋白与细菌结合能力。从构建的家蝇(Musca domestica)幼虫cDNA质粒文库中筛选到PGRP-SA基因,以cDNA质粒为模板设计引物,通过PCR扩增,获得PGRP-SA基因完整编码序列。运用生物信息学方法对该基因及其编码蛋白进行预测和分析。构建pET-28a(+)-PGRP-SA重组质粒,转化到大肠杆菌BL21(DE3)中进行诱导表达及蛋白纯化。利用半定量RT-PCR检测PGRP-SA在家蝇3龄幼虫不同组织中的表达量差异。PGRP-SA重组蛋白进行微生物结合实验。结果表明,PGRP-SA基因ORF全长615 bp,编码204个氨基酸,理论分子量22.8 k D,等电点9.11,具有保守的PGRP结构域。成功构建了pET-28a(+)-PGRP-SA重组质粒,蛋白经IPTG诱导后在大肠杆菌中获得表达,经亲和层析柱纯化获得目的蛋白,利用Western blot检测证明纯化蛋白与预期大小相符。PGRP-SA在家蝇3龄幼虫血淋巴、脂肪体、前肠、中肠、气管、马氏管都有表达,血淋巴组织中表达量最高,后肠无表达,由此说明PGRP-SA基因的表达具有一定的组织性。PGRP-SA重组蛋白能与金黄色葡萄球菌和大肠杆菌结合,与白色念珠菌不能结合。成功表达及纯化家蝇PGRP-SA蛋白,证实家蝇PGRP-SA能与金黄色葡萄球菌和大肠杆菌结合。

关键词：家蝇先天免疫肽聚糖识别蛋白原核表达微生物结合实验

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基于身份部分盲签名方案的分析与改进

计算机工程与科学 2018年第12期40卷 2193-2197页

作者：曹素珍戴文洁王彩芬王秀娅孙晗左为平西北师范大学计算机科学与工程学院甘肃兰州730070 天水师范学院数学与统计学院甘肃天水741001

部分盲签名致力于解决匿名性和可控性之间的矛盾,在保护用户隐私的同时又能在必要时追溯用户身份。目前基于身份的部分盲签名方案中普遍存在公共信息被篡改的问题。通过对刘二根的方案的安全性分析,指出其方案中用户可以非法修改公共信... 详细信息

部分盲签名致力于解决匿名性和可控性之间的矛盾,在保护用户隐私的同时又能在必要时追溯用户身份。目前基于身份的部分盲签名方案中普遍存在公共信息被篡改的问题。通过对刘二根的方案的安全性分析,指出其方案中用户可以非法修改公共信息。在此基础上,提出一个改进的基于身份的部分盲签名方案。在随机预言模型下,基于离散对数困难问题,证明了方案在满足部分盲性的同时,能有效抵抗适应性选择消息下的存在性伪造攻击。新方案没有使用计算开销较大的双线性对运算,且克服了公共信息被篡改的缺陷,与现有方案相比,在安全和效率方面都有显著提高。

关键词：基于身份部分盲签名双线性对随机预言模型

Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing Li xiufang Li Zi-xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing wang Wei wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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