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41.
碳纳米管/环氧树脂复合材料力学性能影响因素的研究 总被引:6,自引:1,他引:6
本文研究了碳纳米管在环氧树脂中的分散方式及碳纳米管长度对环氧树脂复合材料力学性能的影响,并对单壁与多壁碳纳米管分别制备的环氧树脂复合材料的力学性能进行了分析探讨。本实验条件如下:搅拌时间为8h时复合材料的冲击强度、拉伸强度和弯曲强度分别可比1h时增加41%、22%和38%;超声波处理时间为4h时复合材料的冲击强度、拉伸强度和弯曲强度分别可比处理1h时增加143%、30%和45%,但超声波处理时间不宜过长,否则会破坏碳纳米管表面,导致性能下降。短碳纳米管在环氧树脂中的分散性较好,对环氧树脂复合材料的增强效果较好。长碳纳米管对提高复合材料的韧性有利。与长度为50μm时相比,碳纳米管长度为2μm时制备的环氧树脂复合材料的拉伸强度和弯曲强度高49.2%和45.3%,但断裂伸长率低33%。与单壁碳纳米管相比,多壁碳纳米管与环氧树脂的界面结合力更好,更适于做环氧树脂增韧材料。相同实验条件下多壁碳纳米管/环氧树脂复合材料的冲击强度、断裂伸长率和拉伸强度较单壁碳纳米管/环氧树脂复合材料可分别提高31%、24%和28%。 相似文献
42.
醇处理对静电纺MWNTs/丝素/聚酰胺复合纤维的影响 总被引:1,自引:0,他引:1
醇蒸汽对改善静电纺纤维的结构与性能具有重要作用。采用静电纺丝的方法制备了MWNTs/丝素/聚酰胺6/66复合纤维毡,并用无水乙醇蒸汽对其处理。研究发现,碳纳米管质量分数较少的试样中,纤维发生了溶胀,并粘连在一起,随着碳纳米管质量分数的增加,纤维只是发生了径向膨胀。乙醇蒸汽处理使纤维毡的结晶结构、热稳定性以及力学性能都得到了显著的提高。碳纳米管质量分数为0.1%时,结晶度从55.8%增加到63.9%,断裂强度、初始模量以及断裂伸长分别增加了45%、103%和134%。 相似文献
43.
This review article focuses on several approaches in the characterization and modification of carbon surfaces with electrocoated thin films which has been realized by recent progress in experimental methods. Electropolymerization and electrocopolymerization of π-conjugated polymers (pyrrole, carbazole, N-vinylcarbazole and aniline) onto carbon surfaces are reviewed with 348 references. Particular emphasis is placed on the recent nanoscale surface characterization techniques applied to the resulting electrocoated polymers onto carbon fibers (i.e., scanning electron microscopy (SEM), cyclic voltammetry (CV), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), focused ion beam-secondary ion mass spectroscopy (FIB-SIMS), Fourier transformed infrared spectroscopy (reflectance-FTIR), and Raman spectroscopic measurements). 相似文献
44.
Fang Zhengping Wang Jianguo Gu Aijuan Tong Lifang 《Frontiers of Materials Science in China》2007,1(4):415-422
The effect of multi-walled carbon nanotubes (MWNTs), both amino-functionalized (f-MWNTs) and unfunctionalized (p-MWNTs) on
the curing behavior of epoxy resin (EP) cured with triethanolamine (TEA), was investigated using differential scanning calorimetry
(DSC). Because the triethylenetetramine (TETA) grafted on the f-MWNTs could act as curing agent and the produced tertiary
amine as negative ionic catalysts of curing reaction of EP, so the activation energy of the EP/TEA system was decreased by
the addition of f-MWNTs. Viscosity played a key role in the curing behavior of the EP/TEA/MWNTs system, for high viscosity
of the EP/TEA/MWNTs system could hinder the motion of the functional groups. The curing heat in EP/TEA/f-MWNTs (weight ratio
1/0.1/0.01) system was higher than the neat EP/TEA (weight ratio 1/0.1) system, while the curing heat in EP/TEA/p-MWNTs (weight
ratio 1/0.1/0.01) was lower than the neat system. When the content of f-MWNTs was increased to 2 phr (weight ratio of 1/0.1/0.02),
the curing heat became lower than that of the neat EP/TEA system, which was the result of the higher viscosity of the EP/f-MWNTs/TEA
system. Since the curing heat indicated the curing degree of the system generally, the addition of the f-MWNTs was thought
to increase the curing degree of the epoxy matrix at a relatively low content. 相似文献
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为了研究大面积多壁碳纳米管(MWNTs)的光电响应特性,利用剥离技术和旋涂法制备了大 面积MWNTs薄膜器件;采用532nm激光作为激励光源,当激光照射薄 膜器件不同位置时,测试其光电流和光电 压。实验结果表明,激光诱导产生的光电流/电压与光照位置有关,当光照位置在器件两端 时,光电流、光电压 最大,两端的光电流分别为0.04μA、-0.06μA和光电压分别为0.04mV、-0.06mV; 当激光照射在器件几 何中心时,光电流、光电压趋于0。分析表明,光热电效应是光电流、电压产生和变化的主 要原因。 相似文献
48.
In this article, a facile strategy was developed to prepare BA‐MMA‐GMA/MWNTs (multiwalled carbon nanotubes) hybrid nanoparticles as nanofillers in rubber by single‐step grafting technique. First, a new macromolecular surface modifier butyl acrylate (BA)‐α‐methyl methacrylate(MMA)‐glycidyl methacrylate (GMA) terpolymer was synthesized via radical copolymerization. Afterward, this terpolymer modifier was covalently grafted onto the surface of crude MWNTs by single‐step grafting technique. The structure, surface properties, and thermal stability of modified MWNTs were systematically investigated by FTIR, TGA, and TEM. FTIR results showed that BA‐MMA‐GMA terpolymer was successfully grafted onto the surface of MWNTs. TGA indicated that the optimum mass fraction of macromolecular modifier coated on the surface of MWNTs was 9 wt %. TEM images revealed that an organic coating layer was formed and the modified MWNTs showed good dispersibility in acetone. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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用溶液共混法制得了MWNTs/PS-PVC复合材料,进行了电导率的测试分析.通过对载流子浓度、迁 移率的测量以及电导活化能的计算等分析研究了影响MWNTs/PS-PVC复合材料电导率的因素和导电机制.结 果表明:当PS与PVC的质量比为1∶1时,MWNTs/PS-PVC复合材料的导电阈值最低;当MWNTs的质量分 数为1.5%,PS在PS-PVC基体中的质量分数为50%时,MWNTs/PS-PVC复合材料的电导率比MWNTs/PVC单一聚合物复合材料的提高了4个数量级.在导电网络的形成过程中,MWNTs/PS-PVC复合材料中形成的与无机化合物超晶格结构类似的n-i-p-i结构,降低了MWNTs/PS-PVC复合材料的电导活化能,增加了载流子浓度,使MWNTs/PS-PVC复合材料电导率显著提高. 相似文献