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Active Ageing and Labour Market Outcomes-An Analysis Using Survey Data in Urban India
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作者 Panchanan Das 《Management Studies》 2025年第3期122-134,共13页
This paper undertakes an analysis of labour market outcomes among aging population in Indian labour market by using household and personal level characteristics obtained from periodic labour force survey(PLFS)data for... This paper undertakes an analysis of labour market outcomes among aging population in Indian labour market by using household and personal level characteristics obtained from periodic labour force survey(PLFS)data for 2023-2024.It provides an analysis of the association of demographic and household characteristics with probability of choosing either paid-employment or self-employment by applying discrete choice model,after controlling for sample selection bias.By following strategic choice framework,endogenous sample selected probit model is used in finding out the role of different covariates in determining the chance of continuing work in self-employment and wage employment of any type after the age of statutory retirement.Social,economic,and other factors like gender are considered as key factors towards labour market participation of the aging population.This study examines the effects of age and education on decision to choose type of employment by the people beyond their statutory retirement age.The coefficient of female dummy is positive in regular-paid jobs and unpaid household work,but negative for own accounts work and employer irrespective of age cohorts suggesting that women are more likely to continue as regular paid jobs and unpaid household work,but less likely to be employer and own account worker as compared to men even after age 60 years and above. 展开更多
关键词 ageing population labour force participation developing Asia
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薄源^(110 m)Agγ级联符合修正分析 被引量:1
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作者 杜云武 毕朝文 +3 位作者 王亮 王茜 李元东 余强 《核电子学与探测技术》 北大核心 2025年第5期658-667,共10页
核电厂环境介质中^(110 m)Ag放射性水平一般较低,经浓缩富集制得薄厚度源,薄源的^(110 m)Agγ能谱级联符合效应较大,为了准确测量薄源^(110 m)Ag活度浓度,研究薄源^(110 m)Ag衰变过程γ能谱探测具有重要意义。依据衰变纲图分解^(110 m)A... 核电厂环境介质中^(110 m)Ag放射性水平一般较低,经浓缩富集制得薄厚度源,薄源的^(110 m)Agγ能谱级联符合效应较大,为了准确测量薄源^(110 m)Ag活度浓度,研究薄源^(110 m)Ag衰变过程γ能谱探测具有重要意义。依据衰变纲图分解^(110 m)Ag衰变为12个过程,采用蒙特卡罗仿真^(110 m)Ag衰变过程,记录每个过程无符合计数和符合计数,开展薄源^(110 m)Agγ能谱特征峰和级联符合修正分析。研究表明:^(110 m)Agγ能谱不同能量的特征峰由一个或几个不同衰变过程决定,并且每个衰变过程均发生3或4条γ级联符合相加,使其全能峰计数减少;1384.31 keV、1475.79 keV、1505.04 keV、1562.30 keV全能峰同时受到其他衰变过程级联符合相加峰影响,使其全能峰计数增加;其符合修正因子最大值、最小值分别为1.89、0.77。 展开更多
关键词 衰变纲图 ^(110 m)ag Γ能谱 符合修正
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巯基化改性纤维素复合气凝胶吸附还原Ag(Ⅰ)的研究
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作者 刘以凡 林昱灵 +5 位作者 陈颖 黄靖文 吕源财 林春香 叶晓霞 刘明华 《中国造纸学报》 北大核心 2025年第2期68-77,共10页
以纤维素为原料,通过交联反应引入橡椀单宁,制备单宁-纤维素复合气凝胶(VTCA),再通过酯化反应在VTCA结构上引入巯基,制备巯基化改性纤维素复合气凝胶(TVTCA),分析吸附还原Ag(Ⅰ)前后TVTCA的理化性质变化,考察其对水体中Ag(Ⅰ)的吸附还... 以纤维素为原料,通过交联反应引入橡椀单宁,制备单宁-纤维素复合气凝胶(VTCA),再通过酯化反应在VTCA结构上引入巯基,制备巯基化改性纤维素复合气凝胶(TVTCA),分析吸附还原Ag(Ⅰ)前后TVTCA的理化性质变化,考察其对水体中Ag(Ⅰ)的吸附还原效果,并探讨吸附还原作用机理。结果表明,吸附还原Ag(Ⅰ)后,TVTCA的孔隙结构坍塌,巯基和酚羟基与Ag(Ⅰ)发生了吸附还原作用;在pH值=5的最佳吸附条件下,TVTCA对Ag(Ⅰ)的平衡吸附量达111.67 mg/g;吸附符合准二级动力学模型和Langmuir等温吸附模型,是单分子层的化学吸附过程,属于放热反应。水体中共存离子的影响分析表明,引入巯基后,TVTCA的吸附选择性增强;TVTCA对Ag(Ⅰ)的吸附还原是静电吸引、螯合作用和还原反应的协同效果,其通过静电吸引及巯基和酚羟基的螯合作用将Ag(Ⅰ)吸附并固定至纤维素基气凝胶表面,通过单宁酚羟基将85.79%的Ag(Ⅰ)还原为Ag0。 展开更多
关键词 复合气凝胶 巯基化改性 吸附还原 纤维素 ag(Ⅰ)
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磁控溅射TiO_(2)/Ag光催化薄膜的微结构及性能
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作者 陆昆 江耀红 +1 位作者 赵立军 许俊华 《材料热处理学报》 北大核心 2025年第7期250-258,共9页
光催化技术作为一种高效、安全的环境友好型净化技术,深受人们的重视和关注。传统的TiO_(2)光催化材料在应用过程中仍存在着局限性,难以广泛应用。本研究通过磁控溅射多靶共沉积技术制备了不同Ag含量的TiO_(2)/Ag薄膜,Ag的引入能够极大... 光催化技术作为一种高效、安全的环境友好型净化技术,深受人们的重视和关注。传统的TiO_(2)光催化材料在应用过程中仍存在着局限性,难以广泛应用。本研究通过磁控溅射多靶共沉积技术制备了不同Ag含量的TiO_(2)/Ag薄膜,Ag的引入能够极大地提升薄膜的抗菌性能和可见光响应性能。利用X射线衍射仪(X-ray diffractometer, XRD)、X射线光电子能谱仪(X-ray photoelectron spectrometer, XPS)、高分辨透射电镜(Transmission electron microscopy, TEM)、场发射扫描电镜(Scanning electron microscopy, SEM)、紫外-可见分光光度计(Ultraviolet-visible, UV-Vis)和接触角测量仪等研究了不同Ag含量对薄膜微观结构、润湿性能、抗菌性能和可见光响应性能的影响。结果表明:制备的TiO_(2)/Ag薄膜主要由金红石型TiO_(2)相和Ag相组成;随着Ag含量的增加,薄膜的水滴接触角逐渐增大,在Ag靶功率为45 W时,薄膜具有最佳的疏水性能,接触角为142.27°;Ag元素的掺杂对薄膜的抗菌性能的提升有着显著作用,在Ag靶溅射功率为25 W时,薄膜对大肠杆菌的抑制作用最好,0.25麦氏标准大肠杆菌的抑菌圈直径最大,达到了4.5 mm;TiO_(2)/Ag薄膜吸收带边红移,禁带宽度显著变窄,达到了2.79 eV,薄膜的光响应范围拓宽至可见光区。 展开更多
关键词 磁控溅射 TiO_(2)/ag薄膜 微观结构 光催化 抗菌性能
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基于学生创新能力培养的综合型实验设计——以“Ag系负载型薄膜催化剂的制备及性能研究”为例
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作者 赵娣 陈钰 +4 位作者 刘洪燕 傅丽 李桂花 范爱鑫 魏磊 《云南化工》 2025年第1期104-108,共5页
依托化学与材料科学学院实验室综合训练教学平台的大型仪器资源和科研优势,以Ag系负载型薄膜催化降解有机污染物的反应为基础,提炼设计了薄膜催化剂的设计与制备、表征与分析、性能测试、机理探究等系列实验模块,通过科研问题导向和合... 依托化学与材料科学学院实验室综合训练教学平台的大型仪器资源和科研优势,以Ag系负载型薄膜催化降解有机污染物的反应为基础,提炼设计了薄膜催化剂的设计与制备、表征与分析、性能测试、机理探究等系列实验模块,通过科研问题导向和合作探究实践完成基于创新育人的综合型实验教学。综合型实验不仅使学生掌握电化学制备的基本实验技能和催化性能测试的综合应用能力,激发学生的科研兴趣,提升学生的创新思维和团队合作能力,同时有助于探索以科学研究带动创新人才培养的重要实施路径。 展开更多
关键词 创新能力 综合型实验 ag系薄膜催化剂 光催化性能 实验设计 电化学制备
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Z型异质结复合薄膜UIO-66-NH_(2)/Ag/Ag_(3)PO_(4)/Ni的可见光催化性能及机理
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作者 赵娣 刘洪燕 +4 位作者 王树军 孙欣语 张紫璇 齐学宇 刘子帆 《材料导报》 北大核心 2025年第8期153-158,共6页
设计和合成高效光催化剂需要实现反应位点的精确调控、光诱导载流子的快速迁移以及可见光的有效吸收。本工作采用恒流电沉积法制备了UIO-66-NH_(2)/Ag/Ag_(3)PO_(4)/Ni复合薄膜。UIO-66-NH_(2)和Ag_(3)PO_(4)的能带结构匹配良好,同时纳... 设计和合成高效光催化剂需要实现反应位点的精确调控、光诱导载流子的快速迁移以及可见光的有效吸收。本工作采用恒流电沉积法制备了UIO-66-NH_(2)/Ag/Ag_(3)PO_(4)/Ni复合薄膜。UIO-66-NH_(2)和Ag_(3)PO_(4)的能带结构匹配良好,同时纳米Ag作为光生载流子分离中心,形成了由Ag_(3)PO_(4)、Ag和UIO-66-NH_(2)组成的Z型异质结光催化体系,有效地分离了光生电子-空穴对,保留了强氧化-还原活性位点,因而UIO-66-NH_(2)/Ag/Ag_(3)PO_(4)/Ni复合薄膜在可见光下表现出优异的光催化性能。此外,光电化学测试结果表明,UIO-66-NH_(2)/Ag/Ag_(3)PO_(4)/Ni复合薄膜具有更高的载流子分离速率和更低的催化还原溶解O_(2)的反应势垒。活性物种实验结果表明,·O_(2)^(-)和空穴(h^(+))在光催化降解中起主要作用,进一步证实了系统的Z型异质结光催化降解机制。 展开更多
关键词 UIO-66-NH_(2)/ag/ag_(3)PO_(4)/Ni复合薄膜 Z型异质结 恒流电沉积 可见光 光催化
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基于AGEs-RAGE信号转导通路的鬼箭羽干预糖尿病肾病小鼠作用机制研究 被引量:2
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作者 王瑾瑾 牛钰琪 +2 位作者 马倩倩 左铭钰 闫国立 《中国慢性病预防与控制》 北大核心 2025年第2期126-134,共9页
目的利用网络药理学方法和分子对接技术探究鬼箭羽治疗糖尿病肾病的作用机制,为鬼箭羽治疗糖尿病肾病潜在的作用机制提供理论依据。方法通过中药系统药理学数据库和分析平台(TCMSP)、UniProt数据库筛选鬼箭羽的活性成分及对应靶点;运用G... 目的利用网络药理学方法和分子对接技术探究鬼箭羽治疗糖尿病肾病的作用机制,为鬼箭羽治疗糖尿病肾病潜在的作用机制提供理论依据。方法通过中药系统药理学数据库和分析平台(TCMSP)、UniProt数据库筛选鬼箭羽的活性成分及对应靶点;运用GeneCards、DisGeNet、OMIM及TTD数据库获取糖尿病肾病疾病靶点;利用Venny平台获取两者的交集靶点;使用STRING平台及Cytoscape软件构建PPI网络;通过DAVID数据库及微生信平台进行GO和KEGG富集分析;使用Auto Dock Tools 1.5.7软件进行分子对接。采用db/db小鼠为糖尿病肾病实验研究动物,鬼箭羽干预后检测小鼠肾功能(血肌酐、尿素氮、尿蛋白/尿肌酐),HE、PAS、Masson染色及透射电镜观察肾脏形态与结构;RT-qPCR、免疫组化及Western blot检测相关基因与核心蛋白。采用SPSS 27.0软件进行单因素方差分析。结果获取鬼箭羽与糖尿病肾病的交集靶点124个,PPI网络筛选出7个核心基因。KEGG富集到癌症通路、糖尿病并发症AGEs-RAGE信号通路、脂质与动脉粥样硬化通路、流体剪切应力与动脉粥样硬化通路等。最终确定鬼箭羽治疗糖尿病肾病的核心靶点为糖基化终末产物受体(RAGE)、核转录因子(NF-κB)、血管内皮生长因子(VEGF)、白细胞介素6(IL-6)、肿瘤坏死因子-α(TNF-α)。分子对接结果显示,鬼箭羽的活性成分与核心靶点具有较好的结合能力。动物实验研究结果显示,与模型组比较,鬼箭羽中高剂量组小鼠血肌酐、尿素氮、尿蛋白/肌酐降低,差异均有统计学意义(P<0.05),肾脏组织病理变化减轻。RT-qPCR及Western blot结果显示,与模型组比较,鬼箭羽中高剂量组RAGE、NF-κB、IL-6mRNA及蛋白表达降低(P<0.05)。免疫组化及Western blot结果显示,与模型组比较,鬼箭羽中高剂量组VEGF、TNF-α蛋白表达降低(P<0.05)。结论鬼箭羽能够有效改善糖尿病肾病结构与功能,其作用机制可能是经由AGEs-RAGE信号转导及其下游靶点实现。 展开更多
关键词 鬼箭羽 糖尿病肾病 网络药理学 agEs-RagE信号转导通路
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La掺杂对Ag/SnO_(2)电接触材料性能的影响
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作者 侯海云 徐智超 +4 位作者 徐佳乐 张梦娇 方晨羽 陈苏醒 刘松涛 《西安工程大学学报》 2025年第5期8-16,共9页
为了探究La元素掺杂量对Ag/SnO_(2)电接触材料耐电弧烧蚀性能的影响规律和机理,制备了Ag/SnO_(2)电接触材料和不同La元素添加量的La掺杂Ag/SnO_(2)电接触材料,测试所制备电接触材料的物理性能和耐电弧烧蚀性能,研究结果发现:随着La元素... 为了探究La元素掺杂量对Ag/SnO_(2)电接触材料耐电弧烧蚀性能的影响规律和机理,制备了Ag/SnO_(2)电接触材料和不同La元素添加量的La掺杂Ag/SnO_(2)电接触材料,测试所制备电接触材料的物理性能和耐电弧烧蚀性能,研究结果发现:随着La元素添加量的增加,La掺杂Ag/SnO_(2)电接触材料的密度、硬度先增加后减小,电阻率先减小后增加,电弧作用下的质量损失先减小再增大。当La/Sn摩尔比达到0.25时,La掺杂Ag/SnO_(2)电接触材料的密度、硬度最大,电阻率最低,电弧作用下电接触材料的质量损失最小。相对于Ag/SnO_(2)电接触材料,La/Sn摩尔比达到0.25时,La掺杂Ag/SnO_(2)电接触材料的密度、硬度分别提高1.19%、5.26%,电阻率降低4.67%,电弧烧蚀后的质量损失降低42.00%。表明适量的La掺杂提高了Ag和掺杂SnO_(2)间的界面结合力,Ag/SnO_(2)电接触材料的耐电弧烧蚀性能明显改善,而过量的La掺杂反而会降低La掺杂Ag/SnO_(2)电接触材料的耐电弧烧蚀性能。 展开更多
关键词 ag/SnO_(2)电接触材料 LA掺杂 掺杂量 耐电弧烧蚀性能 影响机理
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The burden of depression,anxiety and schizophrenia among the older population in ageing and aged countries:an analysis of the Global Burden of Disease Study 2019 被引量:8
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作者 Ying Cheng Yu Fang +3 位作者 Jinxin Zheng shiyang Guan Meiti Wang Wu Hong 《General Psychiatry》 CSCD 2024年第1期83-93,共11页
Background Depression,anxiety and schizophrenia among older persons have become global public health challenges.However,the burden of these disorders in ageing and aged countries has not been analysed.Aims To investig... Background Depression,anxiety and schizophrenia among older persons have become global public health challenges.However,the burden of these disorders in ageing and aged countries has not been analysed.Aims To investigate the burden of depression,anxiety and schizophrenia among older adults in ageing and aged countries.Methods Using data from the Global Burden of Disease Study 2019,we calculated the estimated annual percentage change(EAPC)in the age-standardised incidence rates(ASiR)and age-standardised disability-adjusted life years(DALYs)rates(ASDR)for depression,anxiety and schizophrenia of older people in ageing countries(China,India,Indonesia)and aged countries(Japan,Italy,Portugal)between 1990 and 2019.Trends in incidence and DALYs were analysed by gender and age.Results In 2019,the highest incidence of depression,anxiety and schizophrenia in the older population in aged countries was in Japan(927271.3(752552.3-1125796.5),51498.2(37625.7-70487.3)and 126.0(61.0-223.2),respectively),while the highest incidence in ageing countries was in China(5797556.9(4599403.4-7133006.5),330256.1(246448.9-445987.4)and 1067.7(556.2-1775.9),respectively).DALYs for these disorders were similar,with the highest in Japan and China.From 1990 to 2019,the ASIR for depressive disorders decreased in aged countries but increased in ageing countries;the ASIR for anxiety disorders and schizophrenia declined in both ageing and aged countries.The ASDR for depressive disorders was consistent with the ASIR but not for anxiety disorders and schizophrenia.The ASIR for depressive disorders was higher in older women,while the opposite was observed in anxiety disorders and schizophrenia.Notably,the conditions of burden of depressive disorders,anxiety disorders and schizophrenia in the 65-70-year-old age group were the most burdensome.Conclusions The incidence and DALYs of these three mental disorders increased while exhibiting differences between ageing and aged countries.Raising awareness about formulating health policies for preventing and treating mental disorders in the older population is necessary to reduce the future burden posed by the ageing challenge. 展开更多
关键词 SCHIZOPHRENIA BURDEN ageing
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Ag/Bi_(2)O_(2)CO_(3)肖特基结光催化降解环丙沙星性能研究 被引量:1
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作者 王敏 辛德华 +6 位作者 邱云 章薇 王玉春 刘赵荣 史蒙 石乐 谈国强 《陕西科技大学学报》 北大核心 2025年第4期142-151,160,共11页
Bi_(2)O_(2)CO_(3)因其独特的二维层状结构在光催化环境净化领域引起了广泛关注.但太阳能利用率低、光生载流子复合率高等缺点限制了Bi_(2)O_(2)CO_(3)的应用.为了克服上述缺点,本文将高温热聚合和溶剂热反应相结合,制备得到了一系列Ag/... Bi_(2)O_(2)CO_(3)因其独特的二维层状结构在光催化环境净化领域引起了广泛关注.但太阳能利用率低、光生载流子复合率高等缺点限制了Bi_(2)O_(2)CO_(3)的应用.为了克服上述缺点,本文将高温热聚合和溶剂热反应相结合,制备得到了一系列Ag/Bi_(2)O_(2)CO_(3)复合光催化材料,并通过降解环丙沙星评价其光催化性能.结果表明,Ag/Bi_(2)O_(2)CO_(3)的光催化性能明显高于单组分Bi_(2)O_(2)CO_(3).最佳的Ag/Bi_(2)O_(2)CO_(3)样品在模拟太阳光和近红外光照射下对环丙沙星的降解速率分别为0.0254 min^(-1)和0.2272 h^(-1),为Bi_(2)O_(2)CO_(3)的5.91和10.42倍,相应的矿化率分别为69.64%和62.18%.Ag/Bi_(2)O_(2)CO_(3)光催化活性的提高可以归因于金属Ag的局域表面等离激元共振效应和界面肖特基结的协同作用,这不仅增强了材料体系对可见光和近红外光的吸收能力,同时提高了光生电子-空穴对分离效率.此外,所制备Ag/Bi_(2)O_(2)CO_(3)具有良好的循环稳定性.本研究为构筑高活性全光谱响应的Bi_(2)O_(2)CO_(3)基光催化材料提供了新思路. 展开更多
关键词 ag Bi_(2)O_(2)CO_(3) 肖特基结 全光谱催化 环丙沙星
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纳米TiO_(2)/Ag负载海藻酸钙纤维的制备及其抗菌性能 被引量:1
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作者 王洛涛 赵法澍 +1 位作者 朱驯 周彬 《印染》 北大核心 2025年第2期54-56,61,共4页
以钛酸四丁酯、氨基纳米银为原料,采用溶胶-水热法合成了纳米TiO_(2)/Ag分散液,通过浸渍后整理法制备了纳米TiO_(2)/Ag负载海藻酸钙纤维,并对制备的纤维进行表征和抗菌性能测试。透射电镜扫描(TEM)、X射线衍射(XRD)、扫描电镜(SEM)和X... 以钛酸四丁酯、氨基纳米银为原料,采用溶胶-水热法合成了纳米TiO_(2)/Ag分散液,通过浸渍后整理法制备了纳米TiO_(2)/Ag负载海藻酸钙纤维,并对制备的纤维进行表征和抗菌性能测试。透射电镜扫描(TEM)、X射线衍射(XRD)、扫描电镜(SEM)和X射线光电子能谱(XPS)结果显示纳米TiO_(2)/Ag成功负载在海藻酸钙纤维表面。纳米TiO_(2)/Ag负载海藻酸钙纤维对大肠埃希菌和金黄葡萄球菌具有优异的抑菌性能,抗菌率大于99%。 展开更多
关键词 抗菌整理 纳米TiO_(2)/ag 海藻酸钙纤维 静电吸附
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ZnFe_(2)O_(4)@Ag纳米复合材料的制备及其抑菌性能
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作者 张艳艳 房宇 +8 位作者 张萌萌 张滢 吴鹏 魏艳妮 刘晓琴 刘嘉华 丁佳睿 谭玉婷 郭少波 《复合材料学报》 北大核心 2025年第2期1092-1104,共13页
由于传统抗生素和抗菌剂的过度使用,导致大量耐药菌滋生,对社会公共安全和人类健康产生严重威胁。因此,迫切需要开发新一代的抗菌材料来应对耐药菌危害。本文以三氯化铁(FeCl+(3))、氯化锌(ZnCl_(2))和醋酸钠(NaOAc)为原料,采用“一锅... 由于传统抗生素和抗菌剂的过度使用,导致大量耐药菌滋生,对社会公共安全和人类健康产生严重威胁。因此,迫切需要开发新一代的抗菌材料来应对耐药菌危害。本文以三氯化铁(FeCl+(3))、氯化锌(ZnCl_(2))和醋酸钠(NaOAc)为原料,采用“一锅法”合成磁性ZnFe_(2)O_(4)纳米微球,并把平均粒径尺寸为8.8 nm的银纳米颗粒(Ag NPs)吸附到ZnFe_(2)O_(4)表面,制备得到ZnFe_(2)O_(4)@Ag磁性纳米复合材料。该材料可有效防止Ag NPs的团聚,同时小粒径的纳米银可大幅度提升复合材料的抑菌活性,且Zn和Fe元素的引入可提升生物相容性。采用TEM、XPS、XRD、UV-Vis、FTIR及VSM等对复合材料进行系统表征。以革兰氏阴性菌大肠杆菌(E.coli)、革兰氏阳性金黄色葡萄球菌(S.aureus)为测试菌,研究复合材料的抑菌活性和抑菌机制。实验结果表明:ZnFe_(2)O_(4)@Ag在浓度为200μg/mL时,60 min内对E.coli和S.aureus的抑菌活性可达到99.9%,抑菌机制显示:ZnFe_(2)O_(4)@Ag破坏细菌细胞壁与细胞膜,使细菌内溶物及离子泄露,从而使细菌渗透压失衡,导致细菌死亡。同时该复合材料的生物相容性较Ag NPs也大幅度提升。 展开更多
关键词 纳米材料 ZnFe_(2)O_(4)@ag 抑菌 抑菌机制 磁分离
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基于Ag-Ni-Fe纳米复合材料的电化学传感器快速检测水中Hg
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作者 邢晓轲 谷俊华 胡萍 《环境监测管理与技术》 北大核心 2025年第3期71-75,共5页
通过在Fe纳米粒子表面负载一层Ni纳米粒子来提高Fe的稳定性,并在Ni表面负载Ag纳米粒子,制备一种新型的Ag-Ni-Fe纳米复合材料,用来修饰玻碳电极(GCE),构建Ag-Ni-Fe/GCE电化学传感器,实现水中Hg的快速检测。试验表明:Ag-Ni-Fe纳米复合材... 通过在Fe纳米粒子表面负载一层Ni纳米粒子来提高Fe的稳定性,并在Ni表面负载Ag纳米粒子,制备一种新型的Ag-Ni-Fe纳米复合材料,用来修饰玻碳电极(GCE),构建Ag-Ni-Fe/GCE电化学传感器,实现水中Hg的快速检测。试验表明:Ag-Ni-Fe纳米复合材料具有良好的导电性和稳定性,可有效提高Ag-Ni-Fe/GCE传感器的灵敏度;Ag-Ni-Fe/GCE传感器对常见金属离子有良好的抗干扰能力,且在0.05 nmol/L~5.0 nmol/L和5.0 nmol/L~2 300 nmol/L范围内线性良好,方法检出限为0.071 4 nmol/L,实际样品的加标回收率为98.8%~102%。 展开更多
关键词 ag-Ni-Fe纳米复合材料 电化学传感器 快速检测 水质
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On the low cycle fatigue behaviour of an Al-Zn-Mg-Cu alloy processed via non-isothermal ageing 被引量:1
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作者 Guangyi Guo Guofu Xu +5 位作者 Yuan Tang Zhihao Zhao Zhihao Yi Haoran Li Ruohan Wang Xiaoyan Peng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第1期227-238,共12页
The low cycle fatigue behaviour of an Al-Zn-Mg-Cu alloy processed via non-isothermal ageing(NIA)was examined at different strain amplitudes.We showed that NIA improved the low cycle fatigue life(more than 7000 cycles)... The low cycle fatigue behaviour of an Al-Zn-Mg-Cu alloy processed via non-isothermal ageing(NIA)was examined at different strain amplitudes.We showed that NIA improved the low cycle fatigue life(more than 7000 cycles)by optimising the precipitate configuration within 5.5 h while maintaining comparable mechanical properties(570 MPa for tensile strength)and conductivity(nearly 39%IACS)to conventional isothermal ageing,simultaneously.Experimental observation combined with molecular dynamic simula-tion revealed that precipitation configuration manipulated by NIA had a crucial effect on fatigue resis-tance.A great number of repeatedly sheared and locally destructed GP zones enhanced co-planar slip and slip localisation in the under-aged alloy during the early stage of NIA,responsible for the dramatic displacement steps on the surface and resultant poor fatigue performance.As the NIA further proceeded,moderately coarsened precipitates with an average dimension of 6.0 nm and elevated number density ef-fectively impeded the dislocation movement and weaken the slip localisation to a great extent,improving the fatigue performance within a few hours. 展开更多
关键词 Non-isothermal ageing Fatigue Al-Zn-Mg-Cu alloy Precipitate manipulation Slip localization
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Ag掺杂BiOBr花状球压电光催化去除布洛芬
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作者 胡征 王逸 +4 位作者 张广治 林子力 陈平 吕文英 刘国光 《环境科学学报》 北大核心 2025年第4期13-24,共12页
压电光催化系统能够利用机械能和光子能去除污染物.本文通过光还原法成功制备了银掺杂的溴氧化铋(Ag/BiOBr)并利用压电光催化实现了对废水中布洛芬(IBU)的有效去除.X射线衍射(XRD)和扫描电子显微镜(SEM)证明了Ag粒子的成功掺杂.Ag掺杂... 压电光催化系统能够利用机械能和光子能去除污染物.本文通过光还原法成功制备了银掺杂的溴氧化铋(Ag/BiOBr)并利用压电光催化实现了对废水中布洛芬(IBU)的有效去除.X射线衍射(XRD)和扫描电子显微镜(SEM)证明了Ag粒子的成功掺杂.Ag掺杂引起的局域表面等离子体共振(LSPR)效应被紫外-可见漫反射(UV-vis DRS)证实.与纯BiOBr相比,2-Ag/BiOBr具有更高的IBU降解活性,在30 min内可去除95.8%的IBU,是BiOBr的2.24倍,这归因于Ag粒子充当电子介体和LSPR效应导致增强的光吸收性能和光生电荷传输性能.此外,电子自旋共振(ESR)和猝灭实验验证了·O_(2)^(-)和^(1)O_(2)是2-Ag/BiOBr压电光催化降解IBU的主要活性氧物种(ROS).最后,本文提出了3种IBU可能的降解途径,并预测其转化产物的毒性.2-Ag/BiOBr具有稳定性和环境适应性,展现出处理实际水体的潜力.本研究可为BiOBr的改性提供方法参考,并为其在压电光催化降解污染物的实际应用提供理论依据. 展开更多
关键词 ag/BiOBr 压电光催化 布洛芬 电荷分离
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High density dislocations enhance creep ageing response and mechanical properties in 2195 alloy sheet 被引量:1
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作者 WEI Shuo MA Pei-pei +3 位作者 CHEN Long-hui YANG Jian-shi ZHAN Li-hua LIU Chun-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2194-2209,共16页
The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formabilit... The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formability of Al-Cu-Li alloy is vital.A thorough comparison of the effects of cryo-deformation and ambient temperature large pre-deformation(LPD)on the creep ageing response in the 2195 alloy sheet at 160℃with different stresses has been made.The evolution of dislocations and precipitates during creep ageing of LPD alloys are revealed by X-ray diffraction and transmission electron microscopy.High-quality 2195 alloy sheet largely pre-deformed by 80%without edge-cracking is obtained by cryo-rolling at liquid nitrogen temperature,while severe edge-cracking occurs during room temperature rolling.The creep formability and strength of the 2195 alloy are both enhanced by introducing pre-existing dislocations with a density over 1.4×10^(15)m^(−2).At 160℃and 150 MPa,creep strain and creep-aged strength generally increases by 4−6 times and 30−50 MPa in the LPD sample,respectively,compared to conventional T3 alloy counterpart.The elongation of creep-aged LPD sample is low but remains relevant for application.The high-density dislocations,though existing in the form of dislocation tangles,promote the formation of refined T1 precipitates with a uniform dispersion. 展开更多
关键词 creep ageing Al-Cu-Li alloy high dislocation density cryogenic rolling dislocation strengthening
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Dislocation density-me diate d creep ageing behavior of an Al-Cu-Li alloy 被引量:1
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作者 Chang Zhou Lihua Zhan +1 位作者 Chunhui Liu Minghui Huang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第7期204-217,共14页
Creep aging is well-known to be a time-dependent,coupled process of deformation and precipitation strengthening for age-hardening alloys.Its existing mechanisms are mainly attributed to those interac-tions between ato... Creep aging is well-known to be a time-dependent,coupled process of deformation and precipitation strengthening for age-hardening alloys.Its existing mechanisms are mainly attributed to those interac-tions between atomic diffusion and dislocation motion.However,an understanding of the relationship between dislocation density and a special multistage creep behavior,i.e.,double steady creep feature,is still far limited.Here we investigate the effect of various dislocation density levels on such an abnormal multistage creep of an Al-Cu-Li alloy.We find that the increased dislocation densities enable an apparent time decrease(from 6.2 h to 0.8 h)of their first steadyⅡ-stage.The yield strength of post-aged sam-ples increases from 425.0 MPa to 580.0 MPa while the corresponding elongation decreases from 12.3%to 7.3%for the creep-aged samples#1 to#4.Microstructural results also reveal that a great difference in dislocation configuration,tailored by various density levels,results in varying creep processes of theⅡ-stage.This stage is closely related to the nucleation and early growth of T_(1)precipitates.Their number densities(maximum:2.9×10^(19)m^(-3))and the average length(maximum:21.3 nm)of T_(1)precipitates are much smaller than those of the stable peak-aged T_(1)phases,suggesting that creepⅡ-stage of all three creep-aged samples is dominant by the nucleation and initial growth of those T_(1)precipitates.This study provides valuable insights into the dislocation density-mediated creep deformation of an Al-Cu-Li alloy. 展开更多
关键词 Dislocation density Al-Cu-Li alloy Creep ageing T_(1)precipitation
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Gambling to public health in ageing populations: a life expectancy evaluation perspective 被引量:1
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作者 Stanley Chi-on Shiu 《Global Health Journal》 2024年第4期206-212,共7页
Objective:Gambling is a complex topic in relation to health systems.It is always unclear how to strike a balance between the gambling economy and the impact of gambling on public health or social wellbeing at any age.... Objective:Gambling is a complex topic in relation to health systems.It is always unclear how to strike a balance between the gambling economy and the impact of gambling on public health or social wellbeing at any age.There are limited studies considering the association between determinants of gambling and the life expectancy of the ageing population in a country.From an evaluation perspective,this article aims to demonstrate the correlation between life expectancy and gambling and public health systems.Methods:The approach of analysis has two parts.One is the influence of gambling prevalence in populations on life expectancy among old adults.Another is the association between the effect of changes in legal gambling provisions within public health systems and life expectancy among old adults.Healthy adjusted life expectancy at age 60 from the World Health Organization and gross gambling yield were used.ANOVA was performed with SPSS.Results:The population groups with HALE at age 60 of 15 years or over are likely more active in gambling than the population groups with smaller HALE at age 60 of 14 years or less.On the other hand,the influence of a health policy may be sidelined when it is implemented for older adult populations because the resource distribution magnitude or number of strategical techniques may not be the same for younger adult populations.The study here is marked as a good practical start,and there is room for further research with big data analysis on additional gambling variables against other life expectancy variables,quality of life variables or public health system variables.Conclusion:Associations between the determinants of gambling and the life expectancy of the ageing population in a country have not yet been identified.Continuous measurements of policy implementation and effectiveness and assessments of health equity,while gambling policies worldwide continue to change,have not yet been performed.Researchers and policy makers should understand the importance of holistic integration of the gambling economy and policy within a public health and social paradigm with the help of big data insights to achieve sustainability in their cities and health equity in their communities. 展开更多
关键词 ageing GAMBLING Public health Health systems Health policy Life expectancy MEASUREMENTS
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Mitigating the negative catalytic effect of CuO by FAS-17 coated Al nanopowder:Isothermal ageing of Al/CuO nanothermite at 71°C and 60%relative humidity 被引量:1
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作者 Fuwei Li Qian Wang +6 位作者 Jian Cheng Zehua Zhang Yuxuan Zhou Keer Ouyang Jianbing Xu Yinghua Ye Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期156-167,共12页
The safety and reliability of weapon systems would be significantly affected by changes in the performance of energetic materials due to ambient temperature and humidity.Nanothermites have promising applications due t... The safety and reliability of weapon systems would be significantly affected by changes in the performance of energetic materials due to ambient temperature and humidity.Nanothermites have promising applications due to their excellent reactivity.Therefore it becomes extremely important to understand their aging and failure process in the environment before using them.Here,the aging and failure process of Al/CuO in 71°C/60%RH were investigated,and showed that CuO nanoparticles negatively catalyze Al nanopowders,resulting in rapid hydration.The anti-aging effect of FAS-17-coated Al nanopowder was also examined.The aging process of Al,Al/CuO,and Al@FAS-17/CuO in high humidity and heat environment were revealed by quasi-in situ SEM and TEM methods.Compared with the aging of pure Al,the Al nanopowder in the nanothermites strongly agglomerated with the CuO nanopowder and hydrated earlier.This may be caused by CuO catalyzed hydration of Al nanopowder.The energy release experiments showed that the performance of Al/CuO decreased rapidly and failed to ignite after 4 h of aging.In contrast,the Al@FAS-17/CuO thermite can achieve long-term stability of up to 60 h in the same environment by simple cladding of FAS-17.It is found that FAS-17 coated Al nanopowder can prevent both particle agglomeration and water erosion,which is an effective means to make nanothermites application in high humidity and heat environment. 展开更多
关键词 Al/CuO nanothermite FAS-17 coating aging and failure process
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