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991.
Yifen HU Pengyu GAO Zhen XU Chuan ZHANG Lizhen HUANG Yunting HU Yarui AN Yingying GU 《Turkish Journal of Chemistry》2021,45(1):248
Ni(II)/CSs were prepared using a simple two-step hydrothermal method. The morphology and composition of the catalysts were studied with scanning electron microscope, transmission electron microscope, and X-ray diffraction. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy showed that the surface of the prepared carbon spheres was rich in hydroxyl groups, which was beneficial to remove CO intermediates, and therefore, improving the catalytic efficiency and the antipoisoning ability of the catalysts. The results of cyclic voltammetry and chronoamperometry showed that the electrocatalytic activity and stability of Ni(II)/CSs were higher than that of unloaded NiAc under alkaline environment. When the nickel content was 5 wt.%, the peak oxidation current density of methanol on Ni(II)/CSs electrocatalyst reached the maximum of 34.54 mA/cm2, which was about 1.8 times that of unloaded NiAc. These results indicate that Ni(II)/CSs has potential applications in the electrocatalytic oxidation of methanol. 相似文献
992.
以三(4-(吡啶-4-基)苯基)胺和Cu4I4(PPh3)4为原料,在水热条件下合成了一个新的Cu(Ι)配合物[Cu2I2(TPPA)2]n·4H2O[1, TPPA=三(4-(吡啶-4-基)苯基)胺],其结构经IR、元素分析、X-射线单晶衍射表征。1属正交晶系,'P b c n'空间群,晶胞参数a=29.257(5) Å, b=12.621(2)Å, c=18.304(4) Å, α=90°, β=90°, γ=90°。固态荧光测试结果显示,在365 nm激发态下,配合物1在低温时具有多重发射峰,在CIE坐标下对其颜色做了一定的探究,可作为优良发光材料应用于LED上调节白光。
相似文献
993.
PAN Chuanqi LIU Xiaoxuan ZHANG Xiang MAO Feihong XU Peiyan ZHU Yuhua DENG Hongtao LUO Zhu SUN Hongwei ZHANG Lizhi GUO Yanbing 《高等学校化学研究》2021,37(6):1341-1347
Copper oxide(CuO),due to its low cost,good chemical and physical stability,has recently been given special attention as a potential candidate for antibacterial agents.However,developing novel CuO nanocomposites with improved antibacterial property and unraveling the interface promotion mechanism has been a fundamental challenge for decades.Herein,well-defined CuO/graphdiyne(CuO/GDY)nanostructures with uniformly anchored CuO nanoparticles(ca.4.5 nm)have been fabricated.The CuO/GDY nanostructure exhibited superior E.coli inactivation efficiency,which is nearly 19 times and 7.9 times higher than the bare GDY and commercial CuO,respectively.The improved E.coli inactivation performance was mainly due to the increased reactive O2-species generated by the activation of molecular O2 over CuO/GDY surface.These findings demonstrate the efficient antibacterial activity of well-defined CuO/GDY nanostructures and provide insights on the development of efficient GDY-based antibacterial materials. 相似文献
994.
Ultrathin oxide nanofibers are widely used in an array of catalytic applications toward energy conversion and environmental protection. Remarkable progress has been made with regard to the development of engineering oxide nanofibers into unique structures to suit or enable various functions. We aim to provide a comprehensive overview of oxide nanofibers, including the structure engineering, derivates, assemblies and their applications. We begin with a brief introduction to the production of nanofibers with diversified compositions, structures and properties, followed by discussions of the wet-chemistry derivates. Afterward, we discuss the applications of catalytic oxide nanofibers, including electrocata-lysis, photocatalysis and thermal-catalysis. Then we highlight the most significant role of oxide nanofibers as catalyst support for the immobilization of metal nanoparticles. Moreover, we showcase the advanced assemblies based on oxide nanofibers, including their use as multi-functional membranes and foams. In the end, we offer perspectives on the challenges, opportunities and new directions for future development. 相似文献
995.
SHEN Qifei XU Ruohan WANG Zhi ZHAO Tianyu ZHOU Yu XU Yanzi YANG Zhiwei LEI Ming MENG Lingjie DANG Dongfeng 《高等学校化学研究》2021,37(1):143-149
Aggregation-induced emission(AIE)luminogens(AIEgens)with high brightness in aggregates exhibit great potentials in biological imaging,but these AIEgens are seldom applied in super-resolution biological imaging,especially in the imaging by using the structural illumination microscope(SIM).Based on this consideration,we synthesized the donor-acceptor typed AIEgen of DTPA-BTN,which not only owns high brightness in the near-infrared(NIR)emission region from 600 nm to 1000 nm(photoluminescence quantum yield,PLQYs=11.35%),but also displays excellent photo-stability.In addition,AIE nanoparticles based on 4,7-ditriphenylamine-[1,2,5]-thiadiazolo[3,4-c]pyridine(DTPA-BTN)were also prepared with highly emissive features and excellent biocompatibility.Finally,the developed DTPA-BTN-based AIE nanoparticles were applied in the super-resolution cellular imaging via SIM,where much smaller full width at half-maximum values and high signal to noise ratios were obtained,indicating the superior imaging resolution.The results here imply that highly emissive AIEgens or AIE nanoparticles can be promising imaging agents for super-resolution imaging via SIM. 相似文献
996.
无机纳米颗粒在塑料抗紫外的研究中一直备受关注,主要介绍了四种(TiO2、ZnO、SiO2、CeO2)典型的无机纳米颗粒在该领域的应用。首先归纳了其既能吸收又能反射或散射紫外线的抗紫外机理;其次,分别论述了不同无机纳米颗粒适用的紫外光波长范围,以在塑料中的添加方法和应用特点为主线,重点介绍了国内外四种无机纳米颗粒在塑料抗紫外性能中的研究现状和进展;最后,将四种无机纳米颗粒在塑料抗紫外性能中的应用特点进行了对比,提出了应用过程中存在的分散和相容性差等问题,以期为无机纳米颗粒的深入应用和发展提供一定的参考。 相似文献
997.
998.
999.
该研究在前期已制备获得的拟除虫菊酯代谢物3-苯氧基苯甲酸(3-PBA)纳米抗体(Nb)基础上,将其进行生物素化,并利用多聚辣根过氧化物酶标记的链霉亲和素(polyHRP-SA)进行信号扩增,建立了基于生物素-亲和素系统高灵敏间接竞争ELISA检测3-PBA残留的分析方法。对抗原抗体工作浓度、缓冲液条件(pH值、离子浓度、吐温-20浓度)及polyHRP-SA浓度进行优化后,所建方法对3-PBA的半抑制浓度(IC50)为1.7 ng/mL,线性范围为0.37~7.4 ng/mL,检出限(LOD)为0.15 ng/mL。将该方法用于人尿样品(高温酸水解后固相萃取净化)和环境水样品(简单过滤)中3-PBA的检测,加标回收率分别为87.0%~127%和78.0%~113%,相对标准偏差(RSD)不大于10%。该方法具有灵敏度高、操作简便,适用于生物与环境样本中3-PBA的快速筛查。 相似文献
1000.
该文建立了一种简单、高效的新型疏水性低共熔溶剂液液微萃取法,用于提取和富集市售包装豆奶中的三嗪类(阿特拉津、去草净)和苯脲类(灭草隆、绿麦隆)除草剂,并结合高效液相色谱对目标分析物进行分离和测定。以六氟异丙醇为氢键供体,四丁基氯化铵为氢键受体,按照不同摩尔比制备了一系列疏水性低共熔溶剂,并对影响萃取效果的实验条件进行了优化,包括低共熔溶剂的种类及用量、氯化钠用量、涡旋时间、pH值和温度。结果表明,在最佳实验条件下,4种目标物在1.00~500.00 μg/L范围内具有良好的线性关系(r ≥ 0.998 4),检出限和定量下限分别为0.56~0.95 μg/L和1.87~3.16 μg/L,日内和日间相对标准偏差(RSD)分别为0.28%~2.0%和2.1%~7.5%,加标回收率为86.4%~117%。该方法具有操作简单快速、萃取时间短、试剂用量少和实验成本低等优点,可用于市售包装豆奶中三嗪类和苯脲类除草剂的分析检测。 相似文献