排序方式: 共有78条查询结果,搜索用时 15 毫秒
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分别采用循环伏安法和线性扫描伏安法研究了双酚A在多壁碳纳米管修饰玻碳电极上的电化学行为,并建立了一种灵敏简便的检测双酚A的电化学方法。实验结果表明:与裸玻碳电极相比,多壁碳纳米管修饰电极明显提高了双酚A的氧化电流;当外加电压为0~1.0 V、扫描速率为100 mV/s、缓冲溶液pH为5时,双酚A浓度分别在0.05~10.00μmol/L和20.00~100.00μmol/L的范围内与氧化峰电流呈良好的线性关系,检出限为0.013μmol/L。采用该修饰电极对实际试样进行加标回收实验,回收率为97%~104%。 相似文献
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为提高碳纳米材料低压膜污染的可恢复性和强化其灭菌效果,本研究将氧化石墨烯(Graphene oxide,GO)与聚乙二醇(Polyethylene glycol,PEG)非共价改性后的多壁碳纳米管(Multi-walled carbon nanotube,MWCNT)以两种结构形式(共混式/嵌入式)负载到0.45 μm聚醚砜片式膜表面,制备了共混式/嵌入式GO-MWCNT低压膜.进而研究了GO-MWCNT不同结构形式对处理典型污染物(牛血清蛋白、腐殖酸、海藻酸钠)过程中膜污染情况的影响.实验结果显示,MWCNT中GO的添加,可使碳纳米材料膜孔径分布更集中,纯水通量在2.011 L·m-2·h-1·kPa-1以上,属于低压膜的运行范围.在处理小尺寸牛血清蛋白的膜滤过程中,采用共混结构(M系列)的GO-MWCNT膜,缓解污染效果优于顶层嵌入结构(I系列);在处理较大尺寸的腐殖酸、海藻酸钠的膜滤过程中,采用顶层嵌入结构(I系列)的GO-MWCNT膜,缓解污染效果优于共混结构(M系列).GO的添加使得碳纳米材料低压膜的抗蛋白质黏附性能得到有效提高,在保证膜表面粗糙度不会大幅度提高的前提下,添加0.2 mg GO的抗蛋白黏附效果优于添加0.5 mg GO.共混式/嵌入式GO-MWCNT膜均可以充分发挥GO边缘切割杀菌作用,GO投加量与灭菌性能呈正相关.其中,共混结构(M系列)的GO-MWCNT膜灭菌效果优于顶层嵌入结构(I系列). 相似文献
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以石墨粉和纳米TiO2为原料,采用水热法合成了还原氧化石墨烯(RGO)-TiO2纳米管复合光催化剂。运用XRD,TEM,FTIR和UV-Vis DRS技术对该复合光催化剂进行了表征,并考察了其在模拟太阳光下催化还原CO2的活性。表征结果显示:尺寸均一的TiO2纳米管均匀生长在RGO片层表面;RGO的引入拓宽了TiO2纳米管的光响应范围。实验结果表明:TiO2纳米管与适量RGO复合后,光催化还原CO2的活性明显增强;在GO加入量(水热合成时GO质量占GO与TiO2总质量的百分比,GO质量以氧化石墨计)为5%、光催化剂加入量为1.5 g/L的最佳条件下,光催化剂的催化活性是复合前的4倍;RGO-TiO2纳米管复合光催化剂具有良好的重复使用性能。 相似文献
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以钛基氧化物涂层材料(Ti/SnO2-Sb2O5-IrO2)为阳极,碳纳米管修饰的石墨(GE—CNT)为阴极构建电化学系统进行硝酸根(NO3-)去除研究,考察了阴极材料、阴极电位和pH值对电化学法去除水中NO[的影响,同时检测了铵离子(NH4+)和亚硝酸根(NO2-)的生成量。结果表明,利用碳纳米管修饰的石墨阴极可获得较好的硝态氮去除效果;随着阴极电位负移,NO3-去除率随之升高;酸性条件下NO3-去除率最高,NH;生成量也更多。对于由NO3-转化产生的NH4+,在氯离子存在条件下再次进行电化学处理120min,其去除率可达97.1%。 相似文献
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Shengpeng Mo Hui He Quanming Ren Shuangde Li Weixia Zhang Mingli Fu Limin Chen Junliang Wu Yunfa Chen Daiqi Ye 《环境科学学报(英文版)》2019,31(1):136-144
Herein, we reported the synthesis of well-defined Co_3O_4 nanoarrays(NAs) supported on a monolithic three-dimensional macroporous nickel(Ni) foam substrate for use in highefficiency CO oxidation. The monolithic Co_3O_4 NAs catalysts were obtained through a generic hydrothermal synthesis route with subsequent calcination. By controlling the reaction time,solvent polarity and deposition agent, these Co_3O_4 NAs catalysts exhibited various novel morphologies(single or hybrid arrays), whose physicochemical properties were further characterized by using several analytical techniques. Based on the catalytic and characterization analyses, it was found that the Co_3O_4 NAs-6 catalyst with nanobrush and nanomace arrays displayed enhanced catalytic activity for CO oxidation, achieving an efficient 100% CO oxidation conversion at a gas hourly space velocity(GHSV) 10,000 hr~(-1) and 150°C with longterm stability. Compared with the other Co_3O_4 NAs catalysts, it had the highest abundance of surface-adsorbed oxygen species, excellent low-temperature reducibility and was rich in surface-active sites(Co~(3+)/Co~(2+)= 1.26). 相似文献
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目的提高太阳电池阵的可靠性。方法对空间用高轨高压太阳电池阵的静电防护技术进行试验研究,通过外加电弧的方式对太阳电池试验件进行一次放电模拟试验,通过电子注入模拟高轨等离子体环境,采用单一电子能量模拟多能谱能量的环境,对太阳电池阵二次放电进行摸底试验。结果一次放电对太阳电池试验件无影响,二次放电发生时,太阳电池串之间电压的阈值为80 V,二次放电会对太阳电池串输出功率造成一定影响。结论在太阳电池阵设计过程中,控制太阳电池串之间的并联间隙为1 mm,相邻太阳电池串之间电压差不大于80 V、在相邻太阳电池串之间涂敷硅橡胶等方法能有效控制太阳电池阵二次放电的发生,大大提高了太阳电池阵的可靠性。 相似文献
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Multi-walled carbon nanotubes (MWCNTs) were oxidized and characterized by Fourier transform infrared spectroscopy. The adsorption characteristics of the oxidized MWCNT adsorbent were examined using Janus Green (JG) as adsorbate. In batch tests, the effects of pH, adsorbent dose, contact time, and temperature were studied. The maximum adsorption capacity was found to be 56 mg g?1. The experimental data were fitted to the Langmuir, Freundlich, and Tempkin isotherm models, the first one being the most appropriate. Kinetic analysis showed that adsorption was most accurately represented by a pseudo-second-order model. 相似文献