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Facile Synthesis of Ag/TiO2 by Photoreduction Method and Its Degradation Activity of Methylene Blue under UV and Visible Light Irradiation 预览
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作者 Hwei-Cheng Tseng Yu-Wen Chen 《催化剂现代研究(英文)》 2020年第1期1-19,共19页
A series of Ag/TiO2 with various Ag contents were prepared by photoreduction method. Commercial TiO2 from Evonik-Degussa was used as the catalyst. Ag was used as the cocatalyst. This facial synthesis method is cheap a... A series of Ag/TiO2 with various Ag contents were prepared by photoreduction method. Commercial TiO2 from Evonik-Degussa was used as the catalyst. Ag was used as the cocatalyst. This facial synthesis method is cheap and easy. TiO2 was suspended in water with various concentrations of silver nitrate. The solution was illuminated by UV light for 36 h. Ag would deposit on the surface of TiO2. This method can deposit all Ag cation in the starting material on TiO2 after 36 h irradiation by UV light. X-ray diffraction, high resolution-TEM, and X-ray photoelectron spectroscopy were used to characterize the surface, morphology and chemical composition of the catalysts. Photocatalytic degradation of methylene blue in water on these catalysts was carried out under UV and visible light irradiation, respectively. The methylene blue concentration in water was measured by a UV-vis spectrophotometer. The results showed that the bulk structure of TiO2 did not change and some of Ag was incorporated into the surface of TiO2 lattice. The change in the electronic state of Ti on surface is attributed to the replacement of titanium atoms by silver atoms on the TiO2 surface structure which induced visible light response and enhanced the photocatalytic activity. 1 wt% Ag is the optimum loading to have high activity. 展开更多
关键词 Titanium Dioxide Silver PHOTOCATALYST PHOTOREDUCTION PHOTOCATALYTIC Degradation of METHYLENE Blue
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基准转移、结构嵌入与信用离散——近世货币变迁中的白银问题
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作者 邱永志 张国坤 《中国经济史研究》 CSSCI 北大核心 2020年第1期27-40,共14页
元明以降,白银逐步成为举国上下的基准货币,深度影响着中国社会经济的演进路径。围绕白银货币化至货币白银化的历史源起、动态过程、促动机理及影响评价等问题,学界存有广泛争议。本文认为在宋金元时期白银货币化向货币白银化的演进过程... 元明以降,白银逐步成为举国上下的基准货币,深度影响着中国社会经济的演进路径。围绕白银货币化至货币白银化的历史源起、动态过程、促动机理及影响评价等问题,学界存有广泛争议。本文认为在宋金元时期白银货币化向货币白银化的演进过程中,中国货币体系经历了“铜钱基准”的陵夷并转向“白银基准”的内在变动过程。宋金时期白银在“铜钱基准体系”中的作用不断上升,金元之际白银价值基准地位初步确立,为明代货币白银化的出现提供了条件。明代白银通过均则折纳、加耗、折价等形式成规模并结构性地嵌入贡赋体制,并与民间市场上的白银替代一道形成了难以逆转的货币白银化态势。对于中国以银为核心基准的近世货币结构而言,结合信用制度的角度可以看出,在西欧新兴国家信用日益聚合的趋势下,中国社会呈现出信用离散的特征。国家信用层级的缺失、金融技术与构架的迟滞及称量银本身所致的信用外在化、记账单位的紊乱是其最明显的表征,中西方金融体制在信用层面发生日益显见的分流。 展开更多
关键词 白银 基准 贡赋 替代 信用
某银多金属矿石选矿试验研究 预览
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作者 孙洪丽 程晓霞 +2 位作者 康秋玉 张晗 岳辉 《黄金》 CAS 2020年第1期64-68,共5页
针对某银多金属矿石矿物种类多、嵌连关系复杂等特性,进行了混合浮选试验研究,考察了磨矿细度、pH、调整剂、精选次数等因素对浮选指标的影响。结果表明:在磨矿细度-0. 074 mm占75%及最佳药剂、流程结构条件下,采用混合浮选闭路流程,可... 针对某银多金属矿石矿物种类多、嵌连关系复杂等特性,进行了混合浮选试验研究,考察了磨矿细度、pH、调整剂、精选次数等因素对浮选指标的影响。结果表明:在磨矿细度-0. 074 mm占75%及最佳药剂、流程结构条件下,采用混合浮选闭路流程,可获得银品位1 039. 80 g/t、银回收率91. 83%的混合精矿,尾矿银品位降低至7. 66 g/t,混合精矿中铜、铅、锌、钼均获得了较好的富集,回收指标较好。 展开更多
关键词 混合浮选 多金属矿 富集 回收率
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"Hanfu"Reshapes Chinese Fashion Style 预览
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作者 Zhang Peihao 《今日中国:英文版》 2020年第1期64-66,共3页
Not long ago,a group of photos of college graduates caught the attention of many Chinese netizens.Dozens of female students from Hunan University of Chinese Medicine,holding silver needles in front of the statue of Bi... Not long ago,a group of photos of college graduates caught the attention of many Chinese netizens.Dozens of female students from Hunan University of Chinese Medicine,holding silver needles in front of the statue of Bian Que,a legendary ancestor of traditional Chinese medicine,or wandering around in the garden and smelling herbs,posed for graduation photos.What sparked all the buzz was that instead of wearing the standard Western-style bachelor’s graduation gown,they wore colorful traditional Chinese Hanfu clothing.Hanfu means clothing of the Han people,who are the predominant ethnic group in China. 展开更多
关键词 SILVER HUNAN predominant
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硫酸分离-火试金重量法测定碲化铜中的金和银 预览
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作者 李先和 万双 《化学分析计量》 CAS 2020年第1期13-17,共5页
建立了用硫酸分离-火试金重量法测定碲化铜中的金和银含量的方法。用硫酸溶解碲化铜样品,过滤,除去铜和碲,得到含金、银的沉淀物,沉淀物经灰化、配料、高温熔融制得铅扣。将铅扣灰吹,得到金银合粒,用硝酸溶解分离金,用重量法测定金含量... 建立了用硫酸分离-火试金重量法测定碲化铜中的金和银含量的方法。用硫酸溶解碲化铜样品,过滤,除去铜和碲,得到含金、银的沉淀物,沉淀物经灰化、配料、高温熔融制得铅扣。将铅扣灰吹,得到金银合粒,用硝酸溶解分离金,用重量法测定金含量。用金银合粒的质量扣除金粒的质量和分金液、洗液中杂质的质量即为银含量。采用灰皿、残渣熔融法补正,或用含碲、铜物料做基体加入纯金、纯银同试样方法测定,根据金、银的回收率加以补正,从而得到试样中的碲含量。实验结果表明,浓硫酸的加入量为30 mL,残余量应不少于15 mL。火试金中硅酸度为1左右,试样进炉温度以900℃为宜。该方法金、银测定结果的相对标准偏差分别为0.33%~1.97%,0.28%~1.27%(n=9)。金的回收率为98.5%~100.2%,银的回收率为95.5%~101.4%。该法满足生产控制检测和贸易结算的要求。 展开更多
关键词 硫酸分离 火试金重量法 碲化铜
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海外白银流入、被迫通商与银铜平行本位有效性研究--来自1819-1919年清代宁波府的经验证据 预览
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作者 赵红军 《杭州师范大学学报:社会科学版》 CSSCI 2019年第3期105-121,共17页
以1819-1919年海外白银流入、宁波口岸被迫通商背景下的银铜平行本位的有效性问题为考察对象,发现宁波当地相对市场化的银铜比价平行本位体制具有较高的市场有效性,对海外白银流入与宁波被迫通商等都做出了灵敏反应,并且也对冲了相关外... 以1819-1919年海外白银流入、宁波口岸被迫通商背景下的银铜平行本位的有效性问题为考察对象,发现宁波当地相对市场化的银铜比价平行本位体制具有较高的市场有效性,对海外白银流入与宁波被迫通商等都做出了灵敏反应,并且也对冲了相关外部冲击对当地大米价格的负面影响,但这一机制在大米市场的有效性不应被高估。宁波通商口岸的开通,对宁波大米市场产生了正向冲击,其中相对市场化的宁波银铜平行本位制度却在一定程度上抑制了这种外来冲击,说明市场化基础上的和平贸易而不是强迫贸易才是世界贸易可持续发展的人间正道。 展开更多
关键词 白银 清代 宁波 银铜平行本位 银铜比价 米价 市场有效性
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Characterization of Yubileyny Field Ore Potential Based on New Structure-Substance Information 预览
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作者 Lyubov Ilyinichna Yalovik Alexander Vasilyevich Tatarinov 《地质材料(英文)》 2019年第1期1-16,共16页
Spatial-genetic relation of a polycomponent ore mineralization (Au, Ag, PGE, Cu, Pb, Zn, Ni) with dynamometamorphic complex, formed by the picrite-komatiite-tholeiite series rocks of Kelyana-Irokinda greenstone belt, ... Spatial-genetic relation of a polycomponent ore mineralization (Au, Ag, PGE, Cu, Pb, Zn, Ni) with dynamometamorphic complex, formed by the picrite-komatiite-tholeiite series rocks of Kelyana-Irokinda greenstone belt, is identified. Productivity of various ore mineralization morphostructural types (quartz-vein, zones of veining and sulfide dissemination) differing in mineral composition and content of useful components is considered. It is shown that the main industrial value is represented by veined and disseminated ores with relatively poor useful components content, but at the same time forming large-capacity ore zones. The occurrence extent, localization conditions and ore zones hyperthetical resources are favorable for the production of economically cost-effective open pit (quarry) mining operations. An effective sampling method is recommended to carry out the prospect and exploration of large-capacity deposits on the Yubileyny field and other similar to its Transbaikalia ore objects. 展开更多
关键词 ORE MINERALIZATION QUARTZ VEINS Veined ZONES Dynamometamorphic Gold Silver PLATINUM Group Elements
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含银废液中银的回收和利用 预览
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作者 许亚兰 宁梦洁 +2 位作者 陶鹏程 王梦巧 杨明 《武汉轻工大学学报》 2019年第2期91-93,108共4页
实验探究了高温石墨还原法、甲醛还原法和锌粉置换法回收银的效果,并对不同的实验方法进行了分析,高温石墨还原法、甲醛还原法和锌粉置换法回收银的回收率分别为99.3%,98.7%和90.5%。高温石墨还原法具有银的回收率较高,反应时间短,实验... 实验探究了高温石墨还原法、甲醛还原法和锌粉置换法回收银的效果,并对不同的实验方法进行了分析,高温石墨还原法、甲醛还原法和锌粉置换法回收银的回收率分别为99.3%,98.7%和90.5%。高温石墨还原法具有银的回收率较高,反应时间短,实验安全性高,无有害气体产生等特点,值得采用。同时,还对用回收银制备高锰酸银的工艺进行了探讨,并取得了满意的结果。 展开更多
关键词 回收 废液 高锰酸银
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焙烧-氰化浸出锰银矿中银的扩大试验 预览
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作者 王明 齐建云 +1 位作者 宁新霞 王祥 《贵金属》 CAS CSCD 北大核心 2019年第1期47-50,共4页
采用添加剂焙烧-氰化浸出中试处理锰银矿。回转窑连续运转80h,物料焙烧时间30±5min,所得焙砂产率85.54%,焙砂中银含量237.73g/t、锰含量24.68%,银回收率99.19%,锰回收率98.70%;焙砂经500L反应釜直接氰化浸出,浸出液固比2:1~2.2:1,... 采用添加剂焙烧-氰化浸出中试处理锰银矿。回转窑连续运转80h,物料焙烧时间30±5min,所得焙砂产率85.54%,焙砂中银含量237.73g/t、锰含量24.68%,银回收率99.19%,锰回收率98.70%;焙砂经500L反应釜直接氰化浸出,浸出液固比2:1~2.2:1,时间6~15h,氰化钠用量700g/t原矿,所得银浸出率86.5%,氰化尾渣满足冶金用锰矿石标准。 展开更多
关键词 有色金属冶金 焙烧-氰化 中试 锰银矿
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硫化物介质中银合金失泽过程中铜的作用 预览
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作者 J.ORTÍZ-CORONA F.J.RODRÍGUEZ-GÓMEZ 《中国有色金属学报:英文版》 SCIE EI CAS CSCD 2019年第12期2646-2657,共12页
由于暴露在硫化物环境(H2S)中,银和银合金的外观美感和电学性能往往会发生一些变化,这是文化遗产金属制品腐蚀和防护领域的一个问题。采用电化学阻抗谱(EIS)和扫描电子显微镜(SEM)技术分析0.925、0.800和0.720银合金在0.07%(体积分数)... 由于暴露在硫化物环境(H2S)中,银和银合金的外观美感和电学性能往往会发生一些变化,这是文化遗产金属制品腐蚀和防护领域的一个问题。采用电化学阻抗谱(EIS)和扫描电子显微镜(SEM)技术分析0.925、0.800和0.720银合金在0.07%(体积分数)硫化铵溶液中浸没不同时间的失泽过程中铜的作用。极化曲线表明,铜含量和硫化物使腐蚀电流密度增大,延缓银合金的钝化。在开路电势(OCP)处得到的阻抗谱呈现不完整的、压扁的单一容抗弧,表明电荷转移电阻随着合金中铜含量增大而降低。相反,双层电容随着铜含量增大而增大。SEM-EDS分析表明,由于S优先与Cu反应,银合金中的富铜相被选择性溶解,导致局部腐蚀,从而延缓钝化膜的形成。在铜含量较低的合金中观察到明显的局部腐蚀。硫化介质中银合金失泽的机理取决于合金的性质以及铜对硫的较大亲和力。银和铜溶解形成腐蚀产物的过程被认为是速率决定步骤。 展开更多
关键词 保护与修复 失泽 电化学阻抗谱 银合金 腐蚀机理
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Hydrophobicity of Highly Ordered Nanorod Polycrystalline Nickel and Silver Surfaces 预览
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作者 Jan Macko Natália Podrojková +6 位作者 Radim Hrdy Andrej Oriňak Renáta Oriňaková Jaromír Hubálek Jaroslav Vojtu? Zuzana Kostecká Roger M. Smith 《矿物质和材料特性和工程(英文)》 2019年第5期279-293,共15页
Highly ordered nickel and silver nanorods arrays prepared by alumina template assisted electrodeposition were investigated to determine the effect of the array geometry on metal surface hydrophobicity and adhesion for... Highly ordered nickel and silver nanorods arrays prepared by alumina template assisted electrodeposition were investigated to determine the effect of the array geometry on metal surface hydrophobicity and adhesion forces. The nanorod geometry, clustering and pinning were used to characterize surface hydrophobicity and its modulation. A contribution of metal crystallographic orientation to the surface energy was calculated. To characterize nanorod array surface properties and elucidate the source of the particle adhesion effects has been calculated. The dispersive components of surface tension?&gamma;SD?and surface polarizability ks, as surface features that markedly characterize hydrophobicity and adhesion, were calculated. The highest hydrophobicity was found for Ag nanorods with aspect ratio of 10 then Ni nanorods with aspect ratio 10. The same geometry of nanorods particles resulted in different surface hydrophobicity and it was ascribed to the orientation of Ag and Ni crystals formed on the top of nanorods. Due to high hydrophobicity nanorod array surfaces could be used as an antifouling surface in medicine to select areas on implant surface not to be colonized by cells and tissues. 展开更多
关键词 NANORODS Silver NICKEL HYDROPHOBICITY Surface Energy CRYSTALLINITY
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Ag/AgO/羧甲基壳聚糖抗菌水凝胶制备及其释药性能研究
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作者 官淑敏 曹渊 +1 位作者 徐彦芹 王烨 《化工新型材料》 CAS CSCD 北大核心 2019年第5期167-171,共5页
通过银(Ag)/氧化银(AgO)原位沉淀法制备具有pH敏感性的Ag/AgO/羧甲基壳聚糖(CMCS)抗菌水凝胶(Ag/AgO/CMCS)以及载药阿司匹林(ASA)的Ag/AgO/CMCS/ASA载药水凝胶,并对水凝胶的溶胀性能、降解性能、释药性能及抗菌性能的影响进行了研究。... 通过银(Ag)/氧化银(AgO)原位沉淀法制备具有pH敏感性的Ag/AgO/羧甲基壳聚糖(CMCS)抗菌水凝胶(Ag/AgO/CMCS)以及载药阿司匹林(ASA)的Ag/AgO/CMCS/ASA载药水凝胶,并对水凝胶的溶胀性能、降解性能、释药性能及抗菌性能的影响进行了研究。制得的Ag/AgO/CMCS/ASA载药凝胶的网络主要通过氢键和分子间作用力交联,交联点Ag主要以单质Ag和Ag2+态存在。在缓冲溶液pH=7.4条件下,制得的Ag/AgO/CMCS/ASA载药凝胶在12h内的累计释药量为75.20%,对革兰氏阴性大肠杆菌(Ec.oli)的抑制率最大达到92.32%,在医疗领域具有广阔的应用前景。 展开更多
关键词 氧化银 羧甲基壳聚糖 pH敏感性水凝胶 抗菌
Effects of silver nanoparticles with different dosing regimens and exposure media on artificial ecosystem
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作者 Jingwen Zeng Piao Xu +9 位作者 Guiqiu Chen Guangming Zeng Anwei Chen Liang Hu Zhenzhen Huang Kai He Zhi Guo Weiwei Liu Jing Wu Jiangbo Shi 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第1期181-192,共12页
Due to the wide use of silver nanoparticles(AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In thi... Due to the wide use of silver nanoparticles(AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In this study, comparative experiments were conducted to investigate the toxicological impacts of polyvinylpyrrolidone-coated silver nanoparticles(PVP-AgNPs) with two kinds of dosing regimens, continuous and one-time pulsed dosing, in different exposure media(deionized water and XiangJiang River water). There were a number of quite different experimental results(including 100% mortality of zebrafish,decline in the activity of enzymes, and lowest number and length of adventitious roots) in the one-time pulsed dosing regimen at high PVP-AgNP concentration exposure(HOE)compared to the three other treatments. Meanwhile, we determined that the concentration of leached silver ions from PVP-AgNPs was too low to play a role in zebrafish death. Those results showed that HOE led to a range of dramatic ecosystem impacts which were more destructive than those of other treatments. Moreover, compared with the continuous dosing regimen, despite the fact that higher toxicity was observed for HOE, there was little difference in the removal of total silver from the aquatic environment for the different dosing regimens. No obvious differences in ecological impacts were observed between different water columns under low concentration exposure. Overall, this work highlighted the fact that the toxicity of Ag NPs was impacted by different dosing regimens in different exposure media, which may be helpful for assessments of ecological impacts on aquatic environments. 展开更多
关键词 SILVER nanoparticles TOXICITY DOSING REGIMEN SILVER ions ZEBRAFISH
Removal of Stabilized Silver Nanoparticles from Surface Water by Conventional Treatment Processes 预览
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作者 Hafiz H. M. Salih Amro M. El Badawy +1 位作者 Thabet M. Tolaymat Craig L. Patterson 《纳米粒子(英文)》 2019年第2期21-35,共15页
Engineered nanomaterials are used in many applications, including pollution sensors, photovoltaics, medical imaging, drug delivery and environmental remediation. Due to their numerous applications, silver nanoparticle... Engineered nanomaterials are used in many applications, including pollution sensors, photovoltaics, medical imaging, drug delivery and environmental remediation. Due to their numerous applications, silver nanoparticles (Ag NPs) are receiving a large amount of attention. Ag NPs may occur in drinking water sources either during manufacturing, consumption and/or disposal processes. This potentially leads to the presence of Ag NPs in finished drinking water, which could have public health impacts. The objective of this research was to investigate the removal of several types of stabilized Ag NPs by potable water treatment processes. Specifically, this research achieved these objectives through: 1) Synthesis of Citrate-reduced Ag NPs, Polyvinylpyrrolidone stabilized (PVP) Ag NPs and Branched polyethyleneimine stabilized (BPEI) Ag NPs, 2) Characterization of synthesized Ag NPs to determine their aggregation potential, Zeta potential profiles, (pHpzc) and obtain morphological data from SEM images, and 3) An evaluation of the efficacy of conventional water treatment processes (i.e., coagulation, flocculation, sedimentation and sand filtration) in removing stabilized Ag NPs from natural water. The three NPs were found to be stable at the nano size in natural water. Alum coagulation had no impact on the PVP and BPEI Ag NPs. Flocculation and settling were found to be key steps for removal of these NPs. The three Ag NPs were not permanently removed by means of conventional water treatment processes employed in this study. 展开更多
关键词 SILVER Nanoparticles DRINKING WATER WATER Treatment Ag Nano PARTICLE
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Sensitive and Label-Free Detection of Protein Secondary Structure by Amide Ⅲ Spectral Signals using Surface-Enhanced Raman Spectroscopy 预览
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作者 Kang-zhen Tian Chang-chun Cao +2 位作者 Xin-ming Nie Wen Wang Cai-qin Han 《化学物理学报》 SCIE CAS CSCD 2019年第5期603-610,共8页
Proteins and peptides perform a vital role in living systems, however it remains a challenge for accurate description of proteins at the molecular level. Despite that surface-enhanced Raman spectroscopy (SERS) can pro... Proteins and peptides perform a vital role in living systems, however it remains a challenge for accurate description of proteins at the molecular level. Despite that surface-enhanced Raman spectroscopy (SERS) can provide the intrinsic fingerprint information of samples with ultrahigh sensitivity, it suffers from the poor reproducibility and reliability. Herein, we demonstrate that the silver nanorod array fabricated by an oblique angle deposition method is a powerful substrate for SERS to probe the protein secondary structures without exogenous labels. With this method, the SERS signals of two typical proteins (lysozyme and cytochrome c) are successfully obtained. Additionally, by analyzing the spectral signals of the amide Ⅲ of protein backbone, the influence of concentration on the folding status of proteins has been elucidated. With the concentration increasing, the components of α-helix and β-sheet structures of lysozyme increase while the secondary structures of cytochrome c almost keep constant. The SERS method in this work offers an effective optical marker to characterize the structures of proteins. 展开更多
关键词 Surface-enhanced RAMAN SPECTROSCOPY SILVER nanorod Protein SECONDARY structures
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Characterization and Biosorption Performance of Silver by Bacillus Licheniformis 预览
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作者 卞霄婧 柯志滨 +3 位作者 钟超 骆韵涵 刘明华 程扬健 《结构化学》 SCIE CAS CSCD 2019年第1期61-68,2共9页
The demand of silver is increasing rapidly in recent decades, because silver and its related products are widely used in modern industry and decoration. It is necessary to recover silver from waste water using an effi... The demand of silver is increasing rapidly in recent decades, because silver and its related products are widely used in modern industry and decoration. It is necessary to recover silver from waste water using an efficient and environmental friendly method due to its environmental and economic benefits. In this paper, we eliminated the interference of Cl-and light conditions, and then studied the characterization and biosorption performance of silver by Bacillus licheniformis. The max biosorption amount was 87.4 mg/g(dry weight) with the initial Ag+concentration of 100 mg/L at pH 6.0. XRD pattern showed that the product was an amorphous compound. SEM/EDS-mapping and FT-IR results implied that phosphate, amino and carboxyl groups located on the cell walls involved in the biosorption of Ag^+. The XPS spectra result showed that the value of EB of Ag 3d(5/2367.51 eV corresponded to the energy values for Ag(Ⅰ), and indicated Ag^+ adsorbed to the surface of cell still maintained mono-valence. The results confirm that B. licheniformis just adsorb Ag^+ but cannot covert soluble Ag^+ to silver nano-particles(AgNP). 展开更多
关键词 SILVER precious METAL BIOSORPTION BACILLUS LICHENIFORMIS
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基于功能化Fe3O4@Ag纳米粒子快速检测Hg^2+的SERS方法
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作者 左方涛 徐威 赵爱武 《化学学报》 SCIE CAS CSCD 北大核心 2019年第4期379-386,共8页
近年来,汞作为一种重要的污染物引起了人们的广泛关注.迄今为止,基于表面增强拉曼光谱(Surface-enhancedRaman scattering, SERS)的Hg^2+检测方法因其在不同的检测方法中具有高灵敏度而备受关注.基于“turn-off”机制,我们合成出一种磁... 近年来,汞作为一种重要的污染物引起了人们的广泛关注.迄今为止,基于表面增强拉曼光谱(Surface-enhancedRaman scattering, SERS)的Hg^2+检测方法因其在不同的检测方法中具有高灵敏度而备受关注.基于“turn-off”机制,我们合成出一种磁性Fe3O4@Ag (FA)纳米材料用于Hg^2+的SERS 检测.磁等离子体共振纳米颗粒结合了磁共振和等离子体共振特性,可用于高灵敏度和高选择性的汞离子的SERS 检测.通过修饰带正电的聚二烯丙基二甲基氯化铵(PDADMAC, PolyDADMAC, PDDA)层, Fe3O4@Ag表面吸附上带负电的甲基橙探针分子,在Hg2+存在的情况下,可以观察到SERS 信号显著降低.由于Hg^2+与Ag纳米颗粒会快速反应并在Ag 纳米颗粒表面形成一层汞齐,从而影响了Ag 纳米颗粒的表面等离子体共振(Surface Plasmon Resonance, SPR)性能,导致电磁场强度的减弱;同时,这样也会导致Ag 纳米颗粒的表面Zeta 电位的降低,并且影响拉曼探针分子在其表面的吸附,从而进一步导致SERS信号的降低.因此,在含有Hg^2+的情况下, SERS强度的降低主要归因于Hg^2+与AgNPs的相互作用.通过我们的实验可以证明,基于“turn-off”机制检测Hg2+的方法的检测限可以低至10^-10 mol/L.本实验设计的SERS纳米传感器可用于快速检测环境中Hg^2+,为构建重金属离子SERS纳米传感器提供了巨大的潜力. 展开更多
关键词 表面增强拉曼光谱 汞离子(Ⅱ) 磁性纳米材料 快速检测 银纳米粒子
Breaking 12% efficiency in flexible organic solar cells by using a composite electrode
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作者 Guang Zeng Jingwen Zhang +3 位作者 Xiaobin Chen Hongwei Gu Yaowen Li Yongfang Li 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第7期851-858,共8页
The performance of flexible organic solar cells(OSCs)significantly relies on the quality of transparent flexible electrode.Here,we used silver nanowires(AgNWs)with various weight ratios to dope high-conductive poly(3,... The performance of flexible organic solar cells(OSCs)significantly relies on the quality of transparent flexible electrode.Here,we used silver nanowires(AgNWs)with various weight ratios to dope high-conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate(PH1000)to optimize the optical and electronic properties of PH1000 film.A high-quality flexible composite electrode PET/Ag-mesh/PH1000:AgNWs-20 with smooth surface,a low sheet resistance of 6Ω/sq and a high transmittance of 86%at 550-nm wavelength was obtained by doping 20 wt%AgNWs to PH1000(PH1000:AgNWs-20).The flexible OSCs based on the PET/Ag-mesh/PH1000:AgNWs-20 electrode delivered a power conversion efficiency(PCE)of12.07%with an open circuit voltage(Voc)of 0.826 V,a short-circuit current density(Jsc)of 20.90 m A/cm2and a fill factor(FF)of69.87%,which is the highest reported PCE for the flexible indium-tin oxide(ITO)-free OSCs.This work demonstrated that the flexible composite electrodes of PET/Ag-mesh/PH1000:AgNWs are promising alternatives for the conventional PET/ITO electrode,and open a new avenue for developing high-performance flexible transparent electrode for optoelectronic devices. 展开更多
关键词 FLEXIBLE ELECTRODES FLEXIBLE organic solar cells silver NANOWIRE composite ELECTRODE power conversion EFFICIENCY
大面积银微纳光栅的制备及其表面等离子体共振传感特性研究 预览
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作者 陈志伟 郎咸忠 +3 位作者 唐斌 朱熠奇 吴钦 蒋美萍 《电镀与涂饰》 CAS CSCD 北大核心 2019年第7期311-316,共6页
提出了一种基于普通CD-R光盘聚碳酸酯层表面磁控溅射镀银的简便纳米制备技术,用以大面积制备一维银微纳光栅,该光栅可作为高灵敏、低成本的表面等离激元共振(SPR)传感器。通过实验测量和数值计算的方法研究了银层厚度对银微纳光栅SPR的... 提出了一种基于普通CD-R光盘聚碳酸酯层表面磁控溅射镀银的简便纳米制备技术,用以大面积制备一维银微纳光栅,该光栅可作为高灵敏、低成本的表面等离激元共振(SPR)传感器。通过实验测量和数值计算的方法研究了银层厚度对银微纳光栅SPR的影响。结果发现,银层厚度为108 nm的银微纳光栅具有最优的综合传感性能,其灵敏度和品质因数分别达到490 nm/RIU和22 RIU?1。该技术在化学生物传感器制备方面具有潜在的应用价值。 展开更多
关键词 聚碳酸酯 磁控溅射 光栅 表面等离子体共振 时域有限差分法 蔗糖 折射率传感
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电感耦合等离子体质谱法测定水系沉积物中银铜砷锑铋镉 预览
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作者 杨艳明 《冶金分析》 CAS 北大核心 2019年第7期58-64,共7页
水系沉积物中银、铜、砷、锑、铋和镉等金属元素的准确测定,对地质找矿工作具有重要的指导意义。实验采用王水于水浴条件下溶解样品,通过选择适宜的同位素以及选用干扰元素校正方程克服了质谱干扰,利用仪器软件在线校正了氯离子对砷的干... 水系沉积物中银、铜、砷、锑、铋和镉等金属元素的准确测定,对地质找矿工作具有重要的指导意义。实验采用王水于水浴条件下溶解样品,通过选择适宜的同位素以及选用干扰元素校正方程克服了质谱干扰,利用仪器软件在线校正了氯离子对砷的干扰,以2%~3%(V/V)王水为测定介质,建立了电感耦合等离子体质谱法(ICP-MS)测定水系沉积物中银、铜、砷、锑、铋和镉6种元素的方法。在优化的实验条件下,各元素校准曲线线性相关系数均在0.9990以上,方法检出限为0.0028~0.045μg/g,测定下限为0.008~0.13μg/g。采用实验方法测定水系沉积物实际样品中银、铜、砷、锑、铋和镉,测定结果分别与采用交流电弧发射光谱法(ES)测定银,原子荧光光谱法(AFS)测定砷、锑、铋,火焰原子吸收光谱法(FAAS)测定铜,石墨炉原子吸收光谱法(GF-AAS)测定镉的结果基本一致;测得结果的相对标准偏差(RSD,n=11)为0.28%~2.0%。将实验方法应用于水系沉积物标准物质分析,银、铜、砷、锑、铋和镉测定结果的相对标准偏差(n=12)为0.45%~6.0%。 展开更多
关键词 水浴 电感耦合等离子体质谱法(ICP-MS) 水系沉积物
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