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81.
活性染料染色废水的日光脱色降解   总被引:2,自引:0,他引:2  
在太阳光照射条件下,使用铁(Ⅲ)-草酸盐络合物/H2O2对存在于水中三种中温型活性染料进行光催化降解研究,重点考察了太阳光的强度和活性染料的浓度对脱色降解反应的影响结果表明:太阳光的强度低于50001ux,染料的脱色率低于40%;在高于400001ux、照射60分钟脱色率高于98%,在高于900001ux时,照射10分钟,可使活性蓝MS脱色率接近100%,太阳光的强度越高,溶液中的染料浓度越低。  相似文献   
82.
There are many photoaligned azo dyes that can be used for orientation of liquid crystals in various display devices. However, the structure of these compounds needs to be optimized to increase the rate of the process of molecule photoalignment, as well as to spread the application of these compounds. The main coordination metal that presents in the molecules of azo dyes is sodium derivatives. The use of other alkali metals remains an open question. We used quantum‐chemical computation methods and reversible intermolecular bonding model to determine the effect of metal coordination on the velocity of photoalignment. The theoretical predictions were experimentally verified using sodium, potassium, lithium, and cesium salts of the model azo dye synthesized by us. We conclude that potassium azo derivatives are the fastest, ceteris paribus.  相似文献   
83.
The polymeric microspheres were synthesized by the precipitation copolymerization of glycidyl methacrylate (GMA) with methacrylic acid(MAA) or 2‐hydoxyethyl methacrylate (2‐HEMA) containing styrene (ST) in SC‐CO2. Scanning electron microscopy (SEM) showed that the products were spherical microparticles, with the addition of MAA and/or 2‐HEMA as the monomer, with diameter of 0.2–2 μm. The effects of copolymerization pressure, temperature, and ratios of GMA/MAA, ST, and/or GMA/2‐HEMA, on the particle size and morphology were investigated in detail. A new experiment setup is proposed for the large amount of production, based on the rule of lower monomer concentration, more stable system, and better use of the present polymerization apparatus. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2425–2431, 2007  相似文献   
84.
Investigation of the photocatalytic decoloration of nine water-soluble anionic azo dyes widely used for the coloration of textiles was conducted in a photoreactor by a selected reduction based on bisulfite-mediated borohydride. The influence of the irradiation power on their decoloration was discussed in this work. The decoloration processes of two typical azo dyes, Reactive Red MS and C.I. Direct Blue 15 were examined with UV–vis measurement and their decoloration kinetics was also investigated. Moreover, identification of benzidine compounds released from the photoreduction of four direct dyestuffs was undertaken. The results indicated that the reduction of the dyes was significantly enhanced under the increasing irradiation. It was found that the overall degradation followed pseudo-first-order kinetics and two distinct stages were observed in the decoloration processes of Reactive Red MS and C.I. Direct Blue 15. The decay rates at first stage were slightly changed, but the decay rates at second stage were significantly affected by the light intensity. In addition, UV–vis spectra showed that the azo linkages in molecule structure of the dyes were destroyed during the decoloration. Finally, dimethoxyl benzidine or benzidine produced from the photoreduction of four direct dyes was identified as the decoloration products through a rapid spectrophotometric method.  相似文献   
85.
以水杨酸为原料,经硝化、酰卤化、氨化等三步反应,得到重要的染料中间体2,4-二硝基-6-氰苯胺,总收率70.5%。  相似文献   
86.
In order to obtain an efficient hybrid inorganic–organic nonlinear optical (NLO) materials, an azo-dye containing three electronic donor groups 2,5-dimethyl-4-(4′-nitrophenylazo)phenol (DMNPAP) was synthesized and reacted with 3-isocyanatopropyl triethoxysilane (ICTES) to give an alkoxysilane dye (ICTES–DMNPAP). Molecular structural characterizations for DMNPAP and ICTES–DMNPAP were investigated by elemental analysis, 1H NMR, FTIR, UV–visible spectra and differential scanning calorimetry (DSC). The alkoxysilane dye could be hydrolyzed and polymerized in the presence of water, and then transparent hybrid films could be fabricated by spin coating on the indium–tin-oxide (ITO) glass substrates. Compared with the dye 4-nitro-4′-hydroxy-azobenzene (NHA) containing only one hydroxyl as donor group, DMNPAP exhibited larger βCTμg value measured by solvatochromic method, and second harmonic generation (SHG) measurement of the hybrid films was in agreement with the result.  相似文献   
87.
一般的酸性染料溶解度较小,而本文所介绍的单或双偶氮酸性染料,实际上是以碱金属盐的形式存在,由于加入了(按重量计)80%~30%的木质素磺酸铵,改善了室温的冷水溶解度。木质素磺酸铵既作为标准化试剂,用来调节高强度染料到稳定的商品染料,同时又能提高染料在室温时冷水溶解度。  相似文献   
88.
Polymer peroxides were synthesized by copolymerizing tert‐butyl‐3‐isopropenylcumylperoxide (D‐120) with styrene (St). Exothermic peak at 192.7°C in DSC thermogram indicated that peroxy bonds in D‐120 remained intact during the copolymerizing process. The polymeric peroxide was used to initiate polymerization of St. GPC results showed that polystyrene (PS) initiated by the polymeric peroxides was composed of both linear and branched molecules. In addition, the rheology test showed that PS samples initiated by polymeric peroxide contained branched structure and had lower shear viscosities. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 197–202, 2006  相似文献   
89.
分散染料在涤/锦双组分纤维上色差的色度学分析   总被引:3,自引:0,他引:3  
将涤 /锦复合丝分离成单一组分的超细涤纶和锦纶。用常用的分散染料同浴染色后 ,测定了各染色样品的颜色三刺激值 ,并经过色度学计算。实验分析表明 ,分散染料对锦纶染色物的反射光主波长值较相应涤纶染色物向长波方向移动 ;蒽醌类分散染料在锦纶上的得色量较小 ,彩度较低 ;而偶氮类分散染料对涤 /锦染色的总色差较小 ,较适合于涤 /锦复合丝的染色。  相似文献   
90.
Functional polyurethane surfactants (di‐block and tri‐block) were synthesized by addition polymerization of 2,4‐toluenediisocyanate with poly(propylene oxide) and monoallyl‐end‐capped poly(ethylene oxide). The chemical structure of the polyurethane surfactants was confirmed by Fourier transform infrared and 1H NMR spectroscopy. These polymeric surfactants were found to have excellent surface activity. The lowest surface tension of polyurethane surfactant aqueous solutions could be reduced to 37.6 mN m?1. All the polyurethane surfactants synthesized had low critical micelle concentrations and could reduce the surface tension even at very low concentration levels (10?6–10?5 mol L?1). The solubilization of toluene in micelles of the synthesized polyurethane surfactants was studied using UV‐visible spectroscopy, and the results showed that they all exhibited good solubilization capacity. Possible solubilization positions of toluene in the micelles are conjectured. Copyright © 2006 Society of Chemical Industry  相似文献   
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