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ZnO nanowire-nanowall-like hybrid structure on graphene was synthesized with a simple chemical vapor deposition technique. This was done without a template by utilizing a catalyst to control the growth time and condensation. The surface morphology of nanostructure was characterized by using a field emission scanning electron microscope (FE-SEM). We found that the ZnO nanowire-nanowall-like hybrid structure was uniformly deposited on the graphene. The extremely strong ZnO (0002) peaks were observed by using x-ray diffraction (XRD). This method showed the preferred (0001) orientation and high crystalline quality of the ZnO nanostructures. The optical properties were investigated utilizing photoluminescence (PL). These results showed the strong green-yellow emission attributed to the robust inner reflection and scattering. This simplified method has great potential in synthesizing uniform ZnO nanowire-nanowall-like hybrid structures on graphene. These nanostructures may have important applications in new types of flexible gas sensors or other fields demanding high surface area materials. 相似文献
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A nanocomposite film of nitrate glycerol ether cellulose (NGEC)/graphene oxide (GO) was presented by a casting/evaporation technique. The effect of GO contents on mechanical properties of the NGEC/GO films was studied. Compared with pristine NGEC, the integration of 0.5 wt% GO resulted in 40%, 38% and 44% increase in Young's modulus, tensile strength and elongation at break of the NGEC/GO film. 相似文献
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反应合成AgSnO2电接触材料的组织与性能研究 总被引:9,自引:1,他引:9
采用反应合成技术和传统粉末冶金技术制备银氧化锡(AgSnO2)电接触材料。利用千瓦CO2激光器模仿电弧作用在试样表面产生局部熔化,对AgSnO2块体材料进行抗熔蚀性测试。对AgSnO:块体材料进行电导率测试和X射线衍射分析,对块体材料及冷拉拔的AgSnO2线材进行显微组织分析(扫描电镜、透射电镜)。研究结果表明,采用反应合成技术可以在银基体中合成尺寸细小、界面新鲜的SnO2颗粒,所制备的AgSnO2电接触材料中,微米级的SnO2颗粒系由纳米级的SnO2颗粒聚集而成I反应合成法制备的AgSnOz电接触材料较传统粉末冶金法制备的AgSnO2电接触材料具有更高的导电性和抗熔蚀性;该方法制备的AgSnO2电接触材料由于改变了Ag、SnO2的结合状态使材料的加工性能、导电性能和抗熔蚀性同时得到改善和提高。 相似文献
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Shu-Jing Yang Xue-Xue Han Xin-Feng Zhang Song Wang Hai-Lin Cong Xue-Jie Wang 《Integrated ferroelectrics》2020,207(1):62-74
AbstractIn this paper, a multilayer diazo resin-graphene oxide/polyacrylonitrile composite membrane was prepared by layer-by-layer self-assembly and UV-induced modification of commercial polyacrylonitrile (PAN) hollow fiber membranes grafted with diazo resin (DR) and graphene oxide (GO). Scanning electron microscopy (SEM), infrared spectroscopy, contact angle, thermogravimetric analysis (TG), water flux and adsorption properties of heavy metals were studied. The results showed that diazo resin (DR) and graphene oxide (GO) were successfully grafted onto PAN membranes by layer-by-layer self-assembly. Carbonyl and carboxyl groups appeared on the surface of the modified PAN membranes; layer-by-layer self-assembly modification did not destroy the original morphology of PAN membranes, resulting in smaller pore size and higher surface roughness; hydrophilicity of the modified PAN-(DR-GO)3 membranes. The contact angle of pure water decreases from 87.8 degrees to 55.5 degrees, and the water flux increases from 733.30?g.m?1.h?1 to 1250.48?g.m?1.h?1. The thermo gravimetric curves of PAN films before and after modification did not change significantly, and the PAN films before and after modification had good thermal stability. The modified PAN membrane can achieve adsorption equilibrium in a relatively short time, and has good adsorption performance for heavy copper ions, with the adsorption rate as high as 92%. 相似文献
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采用磁控溅射工艺制备了磁损耗型FeCoB-SiO2磁性纳米颗粒膜。利用X射线衍射仪、扫描探针显微镜、透射电子显微镜观测样品的微结构和形貌特征,采用振动样品磁强计、四探针法、微波矢量分析仪及微带短路扫频测量方法测量薄膜试样的磁电性能和微波磁导率。重点分析了SiO2电介质含量、薄膜微结构对样品电磁性能的影响。结果表明,所制备的FeCoB-SiO2纳米颗粒膜具有良好的软磁性能和高频电磁性能,2GHz时复磁导率实部和虚部均高于80,可以应用于抗电磁干扰和微波吸收材料。 相似文献
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Y2O3掺杂ZnO-Bi2O3压敏瓷的显微组织和电性能 总被引:1,自引:0,他引:1
为了提高氧化锌压敏瓷的综合电性能,采用高能球磨制备Y2O3掺杂ZnO压敏瓷,通过扫描电镜和X射线衍射对其显微组织和相成分进行了分析,探讨了Y2O3对氧化锌压敏瓷电性能和显微组织影响机理。结果表明,Y2O3掺杂摩尔分数在0~1.00%时,压敏瓷的电位梯度为332~597V/mm,非线性系数为23.6~40.1,漏电流为0.06~0.90μA。当Y2O3掺杂摩尔分数为0.60%时氧化锌压敏瓷的综合电性能最好,压敏瓷电位梯度为482V/mm,非线性系数为35,漏电流为0.17μA。掺杂Y2O3使压敏瓷晶粒细化是由于Y2O3或者单独以Y2O3氧化物形式存在,钉扎在晶界,阻碍晶粒长大;或者与Bi2O3固溶形成含Y的富铋相,使Bi2O3促进晶粒生长的作用受到抑制。 相似文献
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电树枝是一种发生在高分子材料中的电致裂纹现象,是一种严重威胁以高聚物为主要绝缘材料的电力设备运行安全的电老化现象.为了分析蒙脱土对聚乙烯电树枝化的抑制作用,本文采用熔融插层法制备了聚乙烯/蒙脱土(PE/MMT)复合材料,通过扫描电子显微镜对其结构进行了表征,证实了该复合材料基本上达到了纳米数量级,即形成了纳米复合材料.试验研究了交、直流电压作用下纯聚乙烯(PE)和PE/MMT纳米复合材料的树枝化特性(如电树生长速度、分形维数等特征),结果表明聚乙烯/蒙脱土纳米复合材料对电树具有较好的抑制效果. 相似文献
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叶小亮 《上海电机学院学报》2014,(6):334-337
利用化学气相沉积法制备氧化锌(ZnO)纳米线,通过微加工工艺获得了基于 ZnO 纳米线与ZnO石墨烯量子点纳米复合材料的紫外光探测器。ZnO 石墨烯纳米复合材料的结构和表面形貌通过 X 射线电子衍射和扫描电镜来表征,结果表明,ZnO 纳米线的直径约为33 nm,与石墨烯量子点很好地复合在了一起。利用紫外可见吸收谱对样品的光吸收进行了记录,实验表明,基于ZnO复合石墨烯量子点纳米复合材料的紫外探测器在 UV 照射下显示出良好的光响应行为,该类型基于ZnO复合石墨烯量子点探测器可能在ZnO紫外探测的应用方面具有潜在的意义。 相似文献
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为阐明Cu-Cr-Zr合金时效过程中的组织性演化规律,本文对经过连续铸造、固溶和冷拉拔的Cu-1.5Cr-0.2Zr合金进行时效处理,研究了时效温度和时效时间对该合金组织和性能的影响,并对该合金在不同温度下的时效行为进行了分析。结果表明:对Cu-Cr-Zr合金施以450℃/3 h时效可获得最佳的性能组合,其显微硬度和导电率分别为241 HV和72.5%IACS。时效时合金化元素的脱溶使合金基体的过饱和度降低,发生了合金化元素再分配过程。时效态Cu-Cr-Zr合金的断裂机制为微孔聚集型延性断裂。 相似文献
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In this investigation, PZT films were sputter-deposited on Si/SiO2/Ti/Pt substrates using a dual-target system. The dual targets Pb/PZT(PbZr0.54Ti0.46O3) and PbO/PZT(PbZr0.54Ti0.46O3) were used to reveal the effects of various lead compensation source materials on the microstructure and ferroelectric properties of the films. The structures of the films were characterized by X-ray diffractometry (XRD) and field emission scanning electron microscopy (FESEM). The chemical binding state was determined using X-ray photoelectron spectrometry (XPS). Ferroelectric polarizability was measured using a Radiant Technology RT66A tester. The influence of deposition temperatures on the microstructure and ferroelectric properties of the films was studied. Perovskite PZT films were successfully deposited using the Pb/PZT and the PbO/PZT dual target sputtering systems at a substrate temperature of between 500 and 580C. Structural change was elucidated as a function of deposition temperatures and the lead sources were correlated with the ferroelectric properties of the film. The ferroelectric characteristics of the PZT films deposited using the PbO/PZT dual target were better than those of films deposited using the Pb/PZT dual target, because the former films had a higher bonding energy. 相似文献
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AbstractWith the depletion of petrochemical energy and the greenhouse effect issues caused by petrochemical energy. It is imperative to develop a kind of fuel cell has the advantages of environmental-friendly, energy saving, and low waste emission, which has great potential in future. Therefore, it’s necessary to develop a composite material with low-cost, environmental-friendly, and good stability to replace the Pt-based electrocatalyst. In this research, we prepared the Mn,Ni-doped carbon nanotubes (Mn,Ni/NCNTs) by one-step in-situ method. The transition metal (Mn, Ni) nanoparticles were coated on the acidified-carbon nanotubes to prepare the precursor. After calcined at a certain temperature, the Mn,Ni/NCNTs composite was obtained successfully. The catalytic performance of the catalysts prepared by different transition metals and different calcination temperatures were systematically studied. The results showed the produced composites had layered tubular structure, large surface area, and possessed excellent stability and methanol resistance. This kind of composite is a promising catalyst in the future practical application. 相似文献
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石油焦流化床燃烧过程铁金属脱硝的实验研究 总被引:1,自引:0,他引:1
在流化床内添加脱硝剂是降低氮氧化物排放的有效途径之一,该文对铁基脱硝剂进行了实验研究。在实验室规模流化床反应台架上,模拟流化床燃烧石油焦的气氛,研究了铁对氮氧化物排放的影响,并考察了流化床密相区中CO,石油焦焦炭,石灰石等对铁与氮氧化物之间的多相反应的影响。结果表明:Fe对NO有很强的还原作用;石油焦焦炭和CO对Fe与NO之间的多相反应具有很强的促进作用,可还原Fe的氧化物,延长Fe的作用时间;而石灰石对Fe与NO之间的多相反应几乎没有作用。在流化床燃石油焦过程中,Fe可有效降低NO的排放。 相似文献
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选择性非催化还原脱硝特性试验研究 总被引:10,自引:3,他引:7
采用锅炉燃烧模拟装置研究了氨水和尿素的选择性非催化还原(selective non-catalytic reduction,SNCR)脱硝性能,考察了工况参数对脱硝效率的影响,并研究了添加剂碳酸钠、乙醇、甘油和乙酸甲酯对SNCR脱硝特性的影响。试验结果表明氨水和尿素脱硝适宜工况参数:温度窗口927~
1 110 ℃,最佳反应温度约1 000 ℃,停留时间约为1.2 s,氨氮比为1.5。氨氮比为1.5的典型试验条件下时,氨水和尿素的最大脱硝效率为90%左右。一定参数范围内,增加氨氮比、增加停留时间、较高的初始NO浓度都会提高SNCR脱硝效率。烟气中氧浓度增大尿素的脱硝效率明显降低,氨水的还原能力降低不明显。碳酸钠可以拓宽SNCR温度窗口,并使其向低温方相移动。有机添加剂在较低温度下激发还原反应,提高低温下氨剂还原效率,降低了最大脱硝效率。碳酸钠可以减少喷入氨剂引起的CO排放,在较低温度下有机添加剂可不同程度地增加CO排放。 相似文献