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1.
Polyaniline (PANI) was blended with nylon 6,6 in concentrated H2SO4 and HCl solutions. The solvent coagulation method was utilised to extract short composite fibres of a centimetre in length. A solution of n-butyl acetate, acetone, toluene, 1 μM HCl and chloroform were used as coagulating bath to extract the fibres. The diameters of the fibres ranged from 200 to 300 nm, while the length measured approximately 1 cm, as determined from Scanning Electron Microscopy (SEM). The electrical conductivity varied from 10−4 to 10−2 S/cm for different mass fractions of PANI (xPANI) in the composite fibres. The percolation threshold was reached at xPANI values between 0.15 and 0.2, and further addition of PANI resulted in saturation of the conductivity of the composite fibre. To observe the effect of MWCNTs on the electrical conductivity of the nylon–PANI fibres, 0.04 g, 0.08 g, 0.4 g and 0.5 g of MWCNTs (1, 2, 10, 12.5 weight percentage, respectively) were added into the nylon–PANI solution and were extracted as fibres in the aforementioned solvents. The electrical conductivity of the short fibres increased by an order of magnitude (0.372 S/cm at 12.5 wt.%) when they were extracted in the presence of the MWCNTs. PANI doped in concentrated HCl exhibited an electrical conductivity of 4.46 S/cm.  相似文献   
2.
In this work, the binary N‐CDs@PANI hybrids were fabricated by introducing zero‐dimensional nitrogen‐doped carbon dots (N‐CDs) into reticulated PANI. Firstly, N‐CDs were prepared by one‐pot microwave method, and then, the N‐CDs were introduced into in situ oxidative polymerization of aniline (ANI) monomer. The N‐CDs with abundant functional groups and high electronic cloud density played a significant role in guiding the polyaniline‐ordered growth into intriguing morphologies. Moreover, morphology‐dependent electrochemical performances of N‐CDs@PANI hybrids were investigated and N‐CDs improve static interaction and enhance the special capacitances in the N‐CDs@PANI hybrids. Especially, the specific capacitance of PC4 hybrid can reach 785 F g?1, which exceed that of pure PANI (274 F g?1) at current density of 0.5 A g?1 according to three‐electrode measurement. And the capacitance retention of the PC4 hybrid still keeps 70% after 2000 cycles of charge and discharge. The N‐CDs@PANI hybrids can have potential applications in electrode materials, supercapacitors, nonlinear optics, and microwave absorption.  相似文献   
3.
通过电化学恒电流法,采用苯胺-硫酸电解液在钢片表面合成聚苯胺膜,利用电化学测试技术、扫描电子显微镜、能量散射谱仪和红外光谱仪研究掺杂稀土铈对电化学合成聚苯胺膜在金属基底上的耐蚀性影响。结果表明,稀土铈的掺杂使聚苯胺膜的微观形貌由不规则团块状转变为小薄片正六边形形貌;掺杂稀土铈改性后的聚苯胺膜耐蚀性提高,其交流阻抗弧增大明显,膜层的腐蚀电位向正方向移动,腐蚀电流减小;10%HCI点滴腐蚀t达115 s。  相似文献   
4.
利用电化学氧化还原法在不锈钢基底上制备聚苯胺纳米管(PANI NTs),将Cu2O沉积到PANI NTs,得到Cu2O/PANI/不锈钢电极,通过循环伏安法(CV)研究Cu2O/PANI/不锈钢电极的电化学行为。采用X-射线衍射(XRD)、透射电子显微镜(TEM)对Cu2O/PANI NTs进行结构表征,借助乙酰丙酮分光光度法和气相色谱法对CO2还原产物进行检测。结果表明:PANI在不锈钢基底上以直立的中空纳米管的形式横向生长,内经约为100nm,外径约为200nm;Cu2O/PANI NTs具有优良的光电催化还原性能,对 /CO2具有催化活性;Cu2O/PANI/不锈钢电极光电催化还原CO215h 后溶液中甲醛的浓度为29.5μmol/L。  相似文献   
5.
The polyaniline (PANI)–poly (vinyl alcohol) (PVA) composite film doped with HCl was prepared by adopting PVA as matrix. Effects of PVA content and film drying temperature on properties of HCl–PANI–PVA composite film were studied. A comparison was made for tensile strength, elasticity, conductivity and thermal stability of PVA, HCl–PANI or HCl–PANI–PVA. PVA film presented the highest tensile strength and elasticity (150.8?MPa and 300.0%), but its conductivity was the lowest. The conductivity of HCl–PANI–PVA was the highest (1500?S?m?1), and tensile strength and elasticity of HCl–PANI–PVA were higher than those of HCl–PANI. The order of their thermal stability is PVA?>?HCl–PANI?>?HCl–PANI–PVA before 260°C, and the order of their thermal stability is HCl–PANI?>?HCl–PANI–PVA?>?PVA after 260°C. At the same time, the structure and conductive mechanism of composite materials were characterised and analysed through infrared and scanning electron microscopy (SEM).  相似文献   
6.
Polymer brush coatings for combating marine biofouling   总被引:4,自引:0,他引:4  
A variety of functional polymer brushes and coatings have been developed for combating marine biofouling and biocorrosion with much less environmental impact than traditional biocides. This review summarizes recent developments in marine antifouling polymer brushes and coatings that are tethered to material surfaces and do not actively release biocides. Polymer brush coatings have been designed to inhibit molecular fouling, microfouling and macrofouling through incorporation or inclusion of multiple functionalities. Hydrophilic polymers, such as poly(ethylene glycol), hydrogels, zwitterionic polymers and polysaccharides, resist attachment of marine organisms effectively due to extensive hydration. Fouling release polymer coatings, based on fluoropolymers and poly(dimethylsiloxane) elastomers, minimize adhesion between marine organisms and material surfaces, leading to easy removal of biofoulants. Polycationic coatings are effective in reducing marine biofouling partly because of their good bactericidal properties. Recent advances in controlled radical polymerization and click chemistry have also allowed better molecular design and engineering of multifunctional brush coatings for improved antifouling efficacies.  相似文献   
7.
Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline dissolved in aqueous phosphoric acid. The polymer was characterized by UV–Visible spectroscopy (UV–Vis), thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopic (FTIR) techniques. Hardener free epoxy coating was formulated with 10% PANI. The curing process of epoxy resin by PANI was analyzed using FTIR and a suitable mechanism of curing was suggested. The corrosion protective performance of conventional polyamide cured epoxy and PANI cured epoxy coating on steel has been assessed in 3% NaCl by electrochemical impedance spectroscopy (EIS). The self-healing property of the PANI cured epoxy coating on steel in 3% NaCl was studied by scanning vibrating electrode technique (SVET).  相似文献   
8.
PANI/Ag-TiO2纳米纤维复合材料的制备及其抗菌性能研究   总被引:2,自引:0,他引:2  
采用水热法制备Ag掺杂量不同的Ag/TiO2纳米复合材料,通过原位聚合法制备PANI/Ag-TiO2纳米纤维复合材料,利用XRD、SEM、FT-IR等检测技术对复合材料的结构进行了表征。研究了光源、Ag掺杂量、不同实验菌种等因素对PANI/Ag-TiO2纳米纤维复合材料抗菌性能的影响。结果表明:在无光照射情况下,PANI/Ag-TiO2纳米纤维复合材料具有良好的抗菌性能,在长波紫外光照射情况下,抗菌性能进一步增强。在浓度1 mg/mL时,在无需光照的情况下对4种实验菌种杀菌率均达到99.99%。  相似文献   
9.
To solve the electromagnetic pollution,herein,a CoFe2O4/C/PANI composite was developed by a green route,which was constructed with spinel of metal oxide,graphitized carbon and conductive polymer composites.Benefiting from the designable interfaces and increased dipoles,the microwave dielectric response capability can be boosted significantly and resulted in the enhanced microwave absorbing performance.As revealed by the reflection loss curve,the minimum reflection loss(RLmin) reached-51.81 dB at 12.4 GHz under a matched thickness of 2.57 mm.At 2.5 mm,the effective absorbing band covered 8.88 GHz,suggesting the desirable wideband feature.In our case,the method of utilization of a novel green way to fabricate multiple-component EM absorber can be a promising candidate for high-performance EM absorber.  相似文献   
10.
采用简单的阴离子表面活性剂诱导原位化学聚合法,以过硫酸铵(APS)为氧化剂,在十二烷基硫酸钠(SDS)的盐酸溶液中制得了珊瑚状聚苯胺( PANI)微纳米材料.对所制备的PANI分别采用傅里叶变换红外光谱(FT-IR)、场发射扫描电镜(FE-SEM)进行表征.实验结果表明加入SDS后,可以得到一种珊瑚状分级结构PANI微...  相似文献   
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