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菲与纳米银对胶州湾表层沉积物反硝化作用的复合毒性效应评价 预览
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作者 孙鹏飞 白洁 +3 位作者 李岿然 白晓岩 田延昭 赵阳国 《中国海洋大学学报:自然科学版》 CAS CSCD 北大核心 2020年第1期104-114,共11页
多环芳烃(PAHs)与纳米材料污染已对沉积物生态系统和人类生存环境构成严重威胁,其复合污染的毒性效应环境危害可能更大。为了深入探讨PAHs与纳米材料对近岸表层沉积物反硝化作用的复合毒性效应,本文选取位于胶州湾(JZB)的大沽河河口区(D... 多环芳烃(PAHs)与纳米材料污染已对沉积物生态系统和人类生存环境构成严重威胁,其复合污染的毒性效应环境危害可能更大。为了深入探讨PAHs与纳米材料对近岸表层沉积物反硝化作用的复合毒性效应,本文选取位于胶州湾(JZB)的大沽河河口区(DRE)E站和湾内S站,分别以菲和纳米银代表PAHs和纳米材料,通过测定不同剂量单一及复合污染下沉积物反硝化潜势(PDA)的变化,结合浓度相加模型(CA)、独立作用模型(IA)和中效/联合指数等效图法(CI)三种复合毒性评价方法,评价菲和纳米银对沉积物反硝化潜势的复合毒性效应,并对评价方法进行了优选。结果表明,两种污染物浓度越高,对研究区域反硝化潜势的抑制作用越大。菲、纳米银单一及复合作用下对河口区沉积物反硝化潜势的EC50值分别为44.62、112.49和64.86 mg·kg-1,对湾内分别为61.79、147.05和96.18 mg·kg-1。菲单一作用对反硝化潜势的抑制效应强于纳米银,但复合污染的抑制效应更强。两种污染物对河口区的沉积物反硝化潜势抑制效应强于湾内,可能与河口区具有较高Eh和沉积物颗粒度及较低的pH、盐度和有机质含量有关。三种毒性效应评价方法的结果表明,菲和纳米银的复合污染对2个站位反硝化潜势的毒性效应均为协同作用,且对大沽河河口区的协同作用更强。此外,CI法对复合效应的预测结果比CA和IA法更为接近实际观测值,且CI不需要考虑污染物作用模式的限制,因此认为CI法更适用于评价混合污染对沉积物反硝化作用复合影响的效果。本研究结果表明,菲和纳米银会增强彼此对反硝化菌及反硝化功能的毒性效应,由此推断,PAHs和纳米材料在环境中同时存在时比其单独存在对沉积环境的危害更大。 展开更多
关键词 纳米银 沉积物 反硝化作用 复合毒性
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银系抗菌剂对包装原纸性能的影响 预览
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作者 贾文静 王毓彤 徐朝阳 《包装工程》 CAS 北大核心 2019年第5期103-108,共6页
目的 研究银系抗菌剂对包装原纸抗菌性能、白度和力学性能的影响。方法 选用乙酸银、纳米银、磺胺嘧啶银等3种不同的银系抗菌剂,采用表面涂布的方法制备出抗菌纸;选用大肠杆菌和金黄色葡萄球菌检测其抗菌性能;比较抗菌纸和空白试样的力... 目的 研究银系抗菌剂对包装原纸抗菌性能、白度和力学性能的影响。方法 选用乙酸银、纳米银、磺胺嘧啶银等3种不同的银系抗菌剂,采用表面涂布的方法制备出抗菌纸;选用大肠杆菌和金黄色葡萄球菌检测其抗菌性能;比较抗菌纸和空白试样的力学性能。结果 3种抗菌纸对大肠杆菌和金黄色葡萄球菌均有一定的抗菌效果,抑菌圈直径为0.35~5.46 mm,其中对金黄色葡萄球菌的抗菌效果最为明显;当抗菌液的质量分数为0~0.5%时,随着浓度的增加,乙酸银抗菌纸的抗菌性能随之增加;当抗菌液的质量分数为0~10%时,随着浓度的增加,纳米银抗菌纸的抗菌性能也逐渐增加;当抗菌液的质量分数为0.6%时,磺胺嘧啶银抗菌纸抗菌性能达到最佳;抗菌剂对包装原纸白度有一定影响,但对力学性能的影响不明显。结论 3种抗菌纸对金黄色葡萄球菌的抗菌效果比对大肠杆菌的优良,抗菌纸的抗菌性能与抗菌剂种类和浓度有关;抗菌处理对包装原纸的力学性能和表面结构影响不大,但乙酸银和纳米银抗菌剂会导致纸张白度的下降。 展开更多
关键词 抗菌纸 抗菌性能 乙酸银 纳米银 磺胺嘧啶银
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Biosynthesis of Silver Nanoparticles from <i>Allium ampeloprasum</i>Leaves Extract and Its Antifungal Activity 预览
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作者 Samiyah Saeed Al-Zahrani Saleh Mohammed Al-Garni 《生物材料与纳米技术(英文)》 2019年第1期11-25,共15页
Development of natural based nanomaterial immense interest of researchers involved in eco-friendly biosynthesis of nanoparticles. This research set out to investigate the potential of Allium ampeloprasum leaves extrac... Development of natural based nanomaterial immense interest of researchers involved in eco-friendly biosynthesis of nanoparticles. This research set out to investigate the potential of Allium ampeloprasum leaves extract to synthesize silver nanoparticles (AgNPs), and evaluate their antifungal activity against some toxigenic strains of Aspergillus isolates. In order to achieve this, AgNPs were prepared using plant extracts at room temperature and the formation of AgNPs was visually detected after the color changed to dark brown within few minutes. The biosynthesized AgNPs were characterized using the UV-vis spectroscopy, which confirmed the formation of AgNPs with a maximum peak at 437 nm due to the Plasmon resonance. The main active reduction agents were detected by Fourier Transmission infrared spectroscopy (FTIR). Also, the nanoparticles were characterized using Scanning electron microscope (SEM). The antifungal activity of AgNPs was investigated by agar well diffusion method, which revealed inhibition zones of 8 mm, 10 mm, 11 mm, 11 mm and 14 mm against Aspergillus flavus 1, A. parasiticus, A. flavus 2, A. ochraceus, and A. niger. The minimum inhibition concentration (MIC) was determined using micro broth dilution method. MIC values of AgNPs ranged from 652 - 2500 μg/ml. The fungi treated with AgNPs, were examined with (SEM), it was observed that the treated fungi were damaged. These results suggest that AgNPs have the potential to be used as an ideal eco-friendly approach to control toxigenic fungi. 展开更多
关键词 Silver Nanoparticles ANTIFUNGAL AGNPS Aspergillus ALLIUM ampeloprasum
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<i>Stachytarpheta cayennensis</i>Aqueous Extract, a New Bioreactor towards Silver Nanoparticles for Biomedical Applications 预览
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作者 Francois Eya’ane Meva Joel Olivier Avom Mbeng +12 位作者 Cecile Okalla Ebongue Carsten Schlüsener ülkü K?k?am-Demir Agnes Antoinette Ntoumba Phillipe Belle Ebanda Kedi Etienne Elanga Evrard-Rudy Njike Loudang Moise Henri Julien Nko’o Edmond Tchoumbi Vandi Deli Christian Chick Nanga Emmanuel Albert Mpondo Mpondo Christoph Janiak 《生物材料与纳米技术(英文)》 2019年第2期102-119,共18页
This study reports the preparation and characterization of silver nanoparticles synthesized by the mediation of the plant weed Stachytarpheta cayennensis through solution method. Ultraviolet visible spectroscopy (UV-V... This study reports the preparation and characterization of silver nanoparticles synthesized by the mediation of the plant weed Stachytarpheta cayennensis through solution method. Ultraviolet visible spectroscopy (UV-Vis) determines the presence of nanoparticles in the solution. Infrared spectroscopy (IR) proves organic molecules at the particles interface. Powder X-ray diffraction (PXRD) provides phase composition and crystallinity. Shape was showed by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) demonstrated the elemental mapping of the silver nanoparticles. Hydrogen peroxide scavenging and phosphomolybdenum antioxidant assays, egg albumin denaturation anti-inflammation study, and the formation mechanism complete the study. The particles have been found composed of pure silver Ag and silver chloride AgCl nanocrystallites. The average crystallite sizes were found to be 13 nm and 20 nm for Ag and AgCl respectively. A Rietveld refinement based XRD pattern data followed by Williamson-Hall plot allows a size and strain analysis. Based on SEM, spherical agglomerates materials were formed and EDX proved the presence of Cl- ions. The reaction formation mechanism of Ag and AgCl is proposed to be simultaneous and competitive. The silver nanoparticles moderately inhibit the denaturation of egg albumin and exhibit antioxidant action;hence, the nanoparticles could be considered as a potential source for biomedical applications. 展开更多
关键词 Silver Nanoparticles Stachytarpheta cayennensis Size and Strain ANTI-OXIDANT ANTI-INFLAMMATION
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Characterization and Release Kinetics of Metronidazole Loaded Silver Nanoparticles Prepared from <i>Carica papaya</i>Leaf Extract 预览
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作者 Tenderwealth Clement Jackson Akeem Ayodeji Agboke +3 位作者 Edidiong Jumbo Udofa Adaeze Salome Ucheokoro Blessing Edidiong Udo Nonye Linda Ifekpolugo 《纳米粒子(英文)》 2019年第3期47-54,共8页
Silver nanoparticles were synthesized using eco-friendly method with the extract of Carica papaya as a reducing and stabilizing agent. Metronidazole 200 mg was loaded as a model drug to the silver nanoparticles. The p... Silver nanoparticles were synthesized using eco-friendly method with the extract of Carica papaya as a reducing and stabilizing agent. Metronidazole 200 mg was loaded as a model drug to the silver nanoparticles. The percentage yield of the metronidazole nanoparticle was high (96.00%). The entrapment efficiency 85.60% while the loading capacity was 8.90%. Differential scanning calorimetry showed there was no interaction between the reducing agent and model drug. Characterization of the metronidazole malpractices using UV- vis spectroscopy, zeta sizer, scanning electron microscopy (SEM) was performed. The UV-Vis spectroscopy showed surface plasmon resonance of 435nm for the silver nanoparticle. The mean particle size was 250 nm while the polydispersity index was 0.22. The metronidazole nanoparticle showed an extended and controlled release profile. The kinetics of release was zero-order (R2 = 0.9931) for the metronidazole nanoparticle while the metronidazole normal release tablet followed Higuchi kinetics (R2 = 0.9745). 展开更多
关键词 Silver Nanoparticles ECO-FRIENDLY Synthesis CHARACTERIZATION Kinetics
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载银氧化锌复合涂层在骨科领域中的应用前景 预览
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作者 张腾 尚剑 《医学综述》 2019年第6期1160-1164,共5页
在骨科领域,内置物术后感染是较为严重的并发症,既可能导致手术失败,也可能引起败血症、骨髓炎,甚至死亡。骨折术后延迟愈合或不愈合导致的骨不连在临床中也十分常见。纳米银在骨科中展现了良好的抗菌特性,但纳米银的细胞毒性和生物相... 在骨科领域,内置物术后感染是较为严重的并发症,既可能导致手术失败,也可能引起败血症、骨髓炎,甚至死亡。骨折术后延迟愈合或不愈合导致的骨不连在临床中也十分常见。纳米银在骨科中展现了良好的抗菌特性,但纳米银的细胞毒性和生物相容等问题仍不能忽视。纳米氧化锌具有抗菌活性的同时也可以促进成骨活动。将纳米银和纳米氧化锌结合成载银氧化锌复合物既可以减少高剂量纳米银导致的细胞毒性,又能提高抗菌活性,促进成骨。但载银氧化锌复合物的临床研究较少,真正应用于骨科还需要进一步研究。 展开更多
关键词 纳米银 纳米氧化锌 载银氧化锌 复合涂层 骨科
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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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<i>Syzygium aromaticum</i>L. (Clove) Essential Oil as a Reducing Agent for the Green Synthesis of Silver Nanoparticles 预览
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作者 Matheus Vinicius de Oliveira Brisola Maciel Aline da Rosa Almeida +7 位作者 Michelle Heck Machado Ana Paula Zapelini de Melo Cleonice Gon?alves da Rosa Daniele Ziglia de Freitas Carolina Montanheiro Noronha Gerson Lopes Teixeira Rafael Dutra de Armas Pedro Luiz Manique Barreto 《应用科学(英文)》 2019年第2期45-54,共10页
The present investigation details a green synthesis of silver nanoparticles (AgNP) using the essential oil of Syzygium aromaticum L. (clove) as reducing agent, which is a matrix with a high content of eugenol, an impo... The present investigation details a green synthesis of silver nanoparticles (AgNP) using the essential oil of Syzygium aromaticum L. (clove) as reducing agent, which is a matrix with a high content of eugenol, an important compound for the reducing action of silver nitrate. The synthesis of AgNP was performed at different pH conditions (pH 7, 8, 9 and 10), and was monitored by UV-Vis Spectroscopy, Dynamic Light Scattering (DLS) and Transmission Electron Microscopy. The synthesized nanoparticles presented characteristic Surface Plasmon Resonance bands with maximum absorbance between 405 and 460 nm. The DLS analysis revealed particle sizes from 31 to 72 nm and zeta potential between -30.1 and -50.8 mV indicating good stability against the agglomeration of the particles in solution. The micrographs obtained by TEM showed different particle shapes and a predominance of spherical-shaped nanoparticles, and average size ranging from 27 to 94 nm. The clove-based silver nanoparticles were efficient in controlling the growth of Escherichia coli and Staphylococcus aureus bacteria, and the minimum inhibitory concentration ranged from 60 to 100 μL/mL. This study highlights the feasibility of clove essential oil as an alternative for the synthesis of silver nanoparticles by a simple, inexpensive and eco-friendly method. 展开更多
关键词 Essential Oil CLOVE EUGENOL Silver Nanoparticles ANTIBACTERIAL Activity
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纳米银与银离子对土壤微生物及酶活性的影响 预览
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作者 舒昆慧 张丽 +1 位作者 伍玲丽 司友斌 《生态毒理学报》 CAS CSCD 北大核心 2019年第2期242-250,共9页
为研究纳米银和银离子对土壤微生物的影响,采用土壤培养方式,对不同剂量纳米银(10、50、100mg·kg^-1)和银离子(1、5、10mg·kg^-1)暴露下黄褐土、砖红壤中可培养微生物数量及土壤酶活性(脲酶、荧光素二乙酸酯水解酶、蔗糖酶、... 为研究纳米银和银离子对土壤微生物的影响,采用土壤培养方式,对不同剂量纳米银(10、50、100mg·kg^-1)和银离子(1、5、10mg·kg^-1)暴露下黄褐土、砖红壤中可培养微生物数量及土壤酶活性(脲酶、荧光素二乙酸酯水解酶、蔗糖酶、过氧化氢酶)进行研究,并采用纯培养方法对纳米银和银离子暴露下的大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)凋亡情况进行检测,对纳米银释放的银离子毒性进行评估。结果表明,随着纳米银剂量的增加,土壤可培养微生物数量显著减少,脲酶和过氧化氢酶活性降低,蔗糖酶、荧光素二乙酸酯水解酶(FDA酶)活性没有显著变化;银离子处理中微生物数量明显减少,但土壤酶活性被激活。10mg·L^-1纳米银暴露1h后大肠杆菌、金黄色葡萄球菌凋亡率、死亡率增高;随着培养时间的延长,纳米银缓慢释放银离子,并促进大肠杆菌的凋亡。综上分析,纳米银能够抑制土壤可培养微生物生长和酶活性,其中脲酶、过氧化氢酶对纳米银较为敏感,蔗糖酶、FDA酶受纳米银的影响较小;纳米银的毒性一方面是其本身的特异抗菌性,也有部分来自缓慢释放的银离子。 展开更多
关键词 纳米银 银离子 微生物数量 酶活性 土壤
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周期性银纳米颗粒阵列的光学特性
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作者 万巍 陈湛旭 +2 位作者 陈泳竹 陈耿炎 林家勇 《激光与光电子学进展》 CSCD 北大核心 2019年第13期214-219,共6页
利用剪裁的纳米球掩模沉积技术制备了周期性的银纳米颗粒与银纳米孔阵,并探讨了相关纳米结构的光学特性。先在玻璃基片上制备六角密排的聚苯乙烯纳米球作为掩模,然后利用电子束蒸镀银金属,在超声中去掉掩模,最终可以获得周期性的银纳米... 利用剪裁的纳米球掩模沉积技术制备了周期性的银纳米颗粒与银纳米孔阵,并探讨了相关纳米结构的光学特性。先在玻璃基片上制备六角密排的聚苯乙烯纳米球作为掩模,然后利用电子束蒸镀银金属,在超声中去掉掩模,最终可以获得周期性的银纳米三角颗粒。若在蒸镀银金属前先对聚苯乙烯纳米球进行氧等离子体刻蚀,可以获得周期性的银纳米孔阵。测量上述银纳米颗粒与银纳米孔阵中纳米银的透射谱,对其表面等离子体共振特性进行了分析。同时,利用三维时域有限差分方法对相关纳米结构的光吸收特性进行了数值模拟,理论模拟与实验结果基本相符。 展开更多
关键词 光电子学 表面等离子激元 纳米球掩模 银纳米颗粒 银纳米孔阵
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
温度-磁性双重敏感性复合纳米催化剂Fe3O4@Ag/P(NIPAM-co-MPTMS)的合成及性能 预览
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作者 姜春阁 范颖兰 张颖 《陕西师范大学学报:自然科学版》 CAS CSCD 北大核心 2019年第4期76-83,共8页
以负载纳米银粒子的Fe3O4@Ag异质结构为核,N-异丙基丙烯酰胺(NIPAM)和3-(甲基丙烯酰胺)丙基三甲氧基硅烷(MPTMS)为单体,通过乳液聚合法得到Fe3O4@Ag/P(NIPAM-co-MPTMS)有机-无机复合材料。通过透射电子显微镜(TEM)、X-射线光电子能谱(X... 以负载纳米银粒子的Fe3O4@Ag异质结构为核,N-异丙基丙烯酰胺(NIPAM)和3-(甲基丙烯酰胺)丙基三甲氧基硅烷(MPTMS)为单体,通过乳液聚合法得到Fe3O4@Ag/P(NIPAM-co-MPTMS)有机-无机复合材料。通过透射电子显微镜(TEM)、X-射线光电子能谱(XPS)、X射线衍射(XRD)仪、热分析(TGA)和紫外-可见(UV-Vis)分光光度计等手段对Fe3O4@Ag/P(NIPAM-co-MPTMS)有机-无机复合材料的结构、组成和性质进行表征。研究结果表明,通过调节银氨溶液初始浓度可控制纳米银的分散性,且有机-无机杂化网络壳层厚度可通过单体的加入量进行调节。该复合纳米催化剂具有较高的催化活性、温度可调控性和重复使用性。 展开更多
关键词 磁性纳米粒子 纳米银 敏感性 复合纳米催化剂 对硝基苯酚还原
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含金属纳米颗粒化妆品(皂和香波)的制备及性能评价 预览
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作者 张永民(译) 《中国洗涤用品工业》 2019年第2期47-60,共14页
以绿茶提取物为还原剂和稳定剂制备了银和金纳米颗粒,进而化妆品中植入纳米银或纳米金,从而赋予了配方抗菌活性。通过UV-vis吸收光谱分析确认了金属纳米颗粒的成功制备及其在化妆品配方中的成功植入。通过动态光散射分析了金属纳米颗粒... 以绿茶提取物为还原剂和稳定剂制备了银和金纳米颗粒,进而化妆品中植入纳米银或纳米金,从而赋予了配方抗菌活性。通过UV-vis吸收光谱分析确认了金属纳米颗粒的成功制备及其在化妆品配方中的成功植入。通过动态光散射分析了金属纳米颗粒的尺寸大小及分布。利用扫描电子显微镜-X射线能谱对金属纳米颗粒和含金属纳米颗粒的妆品配方的微观结构进行了分析,评价了金属纳米颗粒从化妆品中的释放、在模拟皮肤中的渗透等生理性能,以黑曲霉菌为目标,测量了含金属纳米颗粒化妆品的抗菌性能。结果显示,金属纳米颗粒的引入并不会破坏化妆品配方的稳定性;它们虽然可以穿透皮肤,但短时间内是无法完成的;含金属纳米颗粒的化妆品对黑曲霉菌显示了较强的抗菌活性。 展开更多
关键词 银纳米颗粒 金纳米颗粒 香波 肥皂 抗菌活性
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蜂窝状Ag纳米颗粒膜制备及应用于表面增强拉曼散射基底 预览
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作者 刘元君 叶芬 +3 位作者 王威 张俊豪 晏超 袁爱华 《无机化学学报》 SCIE CAS CSCD 北大核心 2019年第10期1861-1868,共8页
通过静态呼吸图法制备了具有高度有序微结构的聚苯乙烯-嵌段-聚4-乙烯吡啶共聚物(PS-b-P4VP)膜。以该嵌段共聚物膜为模板,可制得金属纳米粒子阵列。借助光化学还原途径制得了具有蜂窝状微结构的Ag纳米颗粒膜。以罗丹明6G(R6G)为探针分子... 通过静态呼吸图法制备了具有高度有序微结构的聚苯乙烯-嵌段-聚4-乙烯吡啶共聚物(PS-b-P4VP)膜。以该嵌段共聚物膜为模板,可制得金属纳米粒子阵列。借助光化学还原途径制得了具有蜂窝状微结构的Ag纳米颗粒膜。以罗丹明6G(R6G)为探针分子,考察了蜂窝状Ag纳米颗粒膜用作表面增强拉曼散射(SERS)基底的性能。蜂窝状Ag纳米颗粒膜对R6G分子的表面拉曼散射增强因子高达1.31×10^9。另外,该SERS基底还显示了较低的检测限,检测限低至10^-10mol·L^-1。拉曼信号面扫显示了基底很好的信号均匀性。在此SERS基底上30μm×30μm范围内随机收集的120个拉曼信号强度的相对标准偏差仅为~12%。 展开更多
关键词 纳米粒子 聚合物 蜂窝状阵列 SERS 呼吸图法
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纳米银对果蝇化蛹、羽化、寿命及细胞凋亡和蛋白表达的影响
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作者 孟帅帅 王博 林欣大 《应用生态学报》 CAS CSCD 北大核心 2019年第10期3579-3588,共10页
纳米银因具有强有效的抗菌作用而被广泛应用于医药领域,然而它存在潜在的生物毒性.本研究选取经典的模式生物黑腹果蝇,探究纳米银对生物体的毒性作用机理.测定不同浓度纳米银处理下的Oregon R、w1118、MTF突变体等品系的化蛹率、羽化时... 纳米银因具有强有效的抗菌作用而被广泛应用于医药领域,然而它存在潜在的生物毒性.本研究选取经典的模式生物黑腹果蝇,探究纳米银对生物体的毒性作用机理.测定不同浓度纳米银处理下的Oregon R、w1118、MTF突变体等品系的化蛹率、羽化时间、羽化率及寿命;用rpr-lacZ品系的lacZ活性测定不同纳米银浓度处理下翅成虫盘的细胞凋亡情况;通过SDS-PAGE研究不同浓度纳米银浓度处理下MTF突变体中肠蛋白的表达差异,并利用质谱分析差异蛋白的氨基酸序列.结果显示:纳米银处理浓度升高至200μg·mL^-1及以上时,MTF突变体化蛹率和羽化率显著降低;纳米银处理浓度升高至800μg·mL^-1时,Oregon R和w1118化蛹率和羽化率显著降低,而化蛹时间和羽化时间与纳米银处理浓度无显著关系.不同浓度纳米银处理对Oregon R和w1118的寿命无影响,而200μg·mL^-1纳米银显著降低MTF突变体平均寿命.随纳米银处理浓度升高,细胞凋亡也逐渐增多.SDS-PAGE及质谱分析表明,随纳米银浓度上升,质子泵ATP激酶、热激蛋白、糖代谢相关酶系等蛋白的表达量上升.本研究表明,高浓度的纳米银会促进细胞凋亡致使部分蛋白表达量发生改变,从而降低果蝇存活率,为后续进一步了解其毒性作用机理提供理论依据. 展开更多
关键词 纳米银 果蝇 细胞凋亡 蛋白表达
基于富里酸的载银碳基吸附剂脱除元素态汞的研究 预览
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作者 刘新强 张华伟 《洁净煤技术》 CAS 2019年第1期136-141,共6页
汞是煤中有害微量元素之一,具有很强的挥发性,几乎所有的汞在煤燃烧过程中都会释放进入大气,对环境和人体健康造成影响。焦炉煤气甲烷化制取液化天然气过程中,为降低元素态汞的污染,通常在液化前将Hg0脱除。本文针对工艺要求,利用富里... 汞是煤中有害微量元素之一,具有很强的挥发性,几乎所有的汞在煤燃烧过程中都会释放进入大气,对环境和人体健康造成影响。焦炉煤气甲烷化制取液化天然气过程中,为降低元素态汞的污染,通常在液化前将Hg0脱除。本文针对工艺要求,利用富里酸廉价、储量丰富、碳含量≥40%、具有亲水性和弱酸性、可与金属离子发生离子交换反应生成络合物等优点,选取富里酸为模板剂和碳源,利用其分子结构中丰富的表面官能团易与银离子螯合的特性,采用冷冻干燥、高温碳化等手段原位合成了纳米银负载的碳基吸附材料Ag/FA,用于低温脱除还原性气体中的元素态汞(Hg0)。对合成的材料进行分析表征,重点考察了操作温度、空速、H2S等因素对吸附剂脱汞性能和寿命的影响。XRD表征结果表明,单质银出现了4个尖锐的衍射峰,分别对应单质银的不同立方晶面,这说明纳米级单质银粒子以高分散形态成功负载到碳材料中,并计算出银颗粒的平均粒径约为12 nm。吸附剂评价结果表明,在反应温度30~60℃,空速小于60 000 h-1时,吸附剂具有良好的脱汞性能,脱汞效率可保持在99%以上,并具有一定抗H2S毒化能力。当穿透率为5%时,吸附剂的汞吸附量可达到650μg/g。Ag/FA吸附剂在经过4次再生后,仍保持95%以上的脱汞效率,且吸附50 h后的Hg0吸附量为552μg/g。Hg-TPD表征结果表明,吸附剂表面负载的纳米银粒子是汞吸附的活性位,气态汞首先扩散到吸附剂表面,然后与吸附剂上负载的银粒子反应生成Ag-Hg合金。本文利用腐植酸可以螯合银离子的特性,制备的基于腐植酸的Ag/FA新型气态汞吸附材料,可有效脱除焦炉煤气甲烷化气体中的单质汞,具有优良的吸附效率和吸附容量。 展开更多
关键词 元素态汞 富里酸 碳材料 纳米银 吸附剂
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银纳米颗粒与抗生素对耐甲氧西林金黄色葡萄球菌的协同抗菌效应研究 预览
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作者 王阳斌 夏永泉 《现代检验医学杂志》 CAS 2019年第5期130-132,共3页
目的观察传统抗生素与银纳米颗粒联用时的体外抗菌效果。方法以耐甲氧西林金黄色葡萄球菌为研究对象,通过纸片扩散法评估银纳米颗粒与抗生素联用时的协同抗菌效应。结果青霉素、红霉素、头孢西丁、阿米卡星等传统抗生素的抑菌效果在与... 目的观察传统抗生素与银纳米颗粒联用时的体外抗菌效果。方法以耐甲氧西林金黄色葡萄球菌为研究对象,通过纸片扩散法评估银纳米颗粒与抗生素联用时的协同抗菌效应。结果青霉素、红霉素、头孢西丁、阿米卡星等传统抗生素的抑菌效果在与银纳米颗粒联用后均出现了不同程度的增强,抑菌环增比率可达0.62~3.69。结论传统抗生素与银纳米颗粒之间具有协同抗菌效应,两者结合使用可有效提高抗菌效率,降低临床抗生素的使用量。 展开更多
关键词 银纳米颗粒 耐甲氧西林金黄色葡萄球菌 抗生素 细菌耐药
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纳米银比色法快速检测三价铬离子 预览
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作者 操江飞 韦寿莲 陈淼鑫 《分析测试学报》 CSCD 北大核心 2019年第10期1270-1274,共5页
利用甲基紫含N供电子配位原子,可通过桥联作用和配位反应吸附于纳米银表面,而Cr3+的引入导致纳米银溶胶发生团聚现象,且溶液的颜色由亮黄色变成灰红色,从而建立了测定痕量Cr3+的比色法。在优化条件下,Cr3+的线性范围为2.0~10.0μmol... 利用甲基紫含N供电子配位原子,可通过桥联作用和配位反应吸附于纳米银表面,而Cr3+的引入导致纳米银溶胶发生团聚现象,且溶液的颜色由亮黄色变成灰红色,从而建立了测定痕量Cr3+的比色法。在优化条件下,Cr3+的线性范围为2.0~10.0μmol·L^-1,r=0.9976,裸眼检出限为0.3μmol·L^-1。方法用于环境中Cr3+的检测,回收率为93.2%~100%,相对标准偏差(RSD)小于1.5%。该方法具有快速、灵敏、选择性好等优点。 展开更多
关键词 纳米银 三价铬离子 甲基紫 比色检测
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Silver Exsolution-Enhanced Electrical Properties of Lanthanum-Based Perovskites 预览
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作者 Rokas Sa?inas Kent Kammer Hansen 《材料科学与工程:中英文A版》 2019年第3期116-129,共14页
The effect of silver(Ag)exsolution on the electrical conductivity of strontium-doped lanthanum manganite(La1-x-ySrxAgyMnO3-δ,LSAM)and ferrite(La1-x-ySrxAgyFeO3-δ,LSAF)perovskites was investigated.The single-phase Ag... The effect of silver(Ag)exsolution on the electrical conductivity of strontium-doped lanthanum manganite(La1-x-ySrxAgyMnO3-δ,LSAM)and ferrite(La1-x-ySrxAgyFeO3-δ,LSAF)perovskites was investigated.The single-phase Ag-doped materials formed at 800℃ using modified Pechini method and revealed thermal stability in oxidizing atmosphere up to sintering temperature of the materials at 1,200℃.The exsolution of the metallic Ag nanoparticles was performed at 420-500℃ in reducing atmosphere of 5%H2/N2.Scanning electron microcopy results exhibited the metallic Ag phase nanoparticles on the surface of the oxide backbone with a good contact of Ag to the surface of the perovskite after exsolution.The electrical conductivity of the materials was investigated in the temperature range of 50-900℃ in air and isothermally in 5%H2/N2 at 420 and 500℃ by means of four probe DC measurement method,and reached 80-230 S·cm^-1 for undoped and Ag-doped LSF and LSM.The electrical conductivity results showed improving conductivity in Ag-doped single-phase and Ag nanoparticle decorated perovskites after Ag exsolution.The results revealed the dependence of electrical conductivity on the atmosphere,temperature and Ag exsolution time. 展开更多
关键词 SILVER nanoparticles EXSOLUTION SOFC cathodes LSM LSF ceramics
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医用银离子抗菌水凝胶敷料的制备及性能研究 预览
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作者 朱新华 黄春兰 +1 位作者 吴丽莎 李雄杰 《当代化工》 CAS 2019年第10期2257-2260,共4页
将纳米银与水凝胶两者性能结合,制备医用银离子抗菌水凝胶敷料,并对其性能进行研究.不使用分散剂,采用水凝胶的纳米孔吸附银离子的方式制备纳米银,使用壳聚糖、冰醋酸、纳米银、泊洛沙姆、碳酸氨、甘油六种试剂制备纳米银抗菌凝胶,并采... 将纳米银与水凝胶两者性能结合,制备医用银离子抗菌水凝胶敷料,并对其性能进行研究.不使用分散剂,采用水凝胶的纳米孔吸附银离子的方式制备纳米银,使用壳聚糖、冰醋酸、纳米银、泊洛沙姆、碳酸氨、甘油六种试剂制备纳米银抗菌凝胶,并采用类似的方式制备纳米银抗菌凝胶敷料.分别对制备得到的水凝胶敷料进行 UV-vis 分析,并测试其抗菌性、溶胀性和生物相容性.实验结果表明,在不添加分散剂和还原剂的条件下,硝酸银可以被还原成纳米银,表明纳米银制备方法可行;水凝胶对大肠杆菌的最大抑菌圈为4.20 mm左右,对葡萄球杆菌的最大抑菌圈为3.52 mm左右,均具有良好的抗菌效果,且纳米银的添加,更加增强了水凝胶的抗菌性;相较于其他甘油含量的水凝胶敷料,添加 2%甘油的敷料具有更好的溶胀性;银离子抗菌水凝胶敷料具有较好的生物相容性,在促进细胞增殖分化方面具有无可比拟的优势. 展开更多
关键词 纳米银 水凝胶 敷料 制备
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