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41.
四异丁氧基镍酞菁的合成及其溶剂效应 总被引:2,自引:0,他引:2
4 异丁氧基邻苯二腈与氯化镍在强有机碱 1 ,8 二氮杂双环 (5 ,4,0 )十一碳烯 7催化下反应 ,合成了四异丁氧基镍酞菁 ,产物经FT -IR、元素分析、UV -Vis吸收光谱和1 H NMR表征了结构 ;并研究了其溶剂效应 ,结果表明 :最大吸收峰波数ν与函数 f(n ,ε)存在一定的线性关系 ,线性相关系数为 0 940 2 ,而Bayliss函数项 (n2 - 1 ) /(2n2 +1 )决定了最大吸收波长 (λmax)的位移变化 ;化合物的λmax在不同溶剂中随聚集程度增加 ,发生一定程度的蓝移 相似文献
42.
ZnFe2O4高温煤气脱硫剂的再生 总被引:1,自引:0,他引:1
在热天平上对自制的ZnFe2O4脱硫剂进行了再生工艺研究,考察了再生温度、O2浓度对ZnFe2O4脱硫剂再生性能的影响;进行了多次硫化、再生循环实验,并与加入玻璃粉的样品进行了比较。结果表明,700℃下氧含量2.0%(vol)时再生可以获得良好的再生率和二次硫化反应活性;玻璃粉的少量加入,会改善脱硫剂长期使用的稳定性,但反应活性有所下降。 相似文献
43.
Silk fibers and membranes were acylated with octadecenylsuccinic anhydride (ODSA) at 75°C for different times. Swelling [N,N‐dimethylformamide (DMF) and dimethyl sulfoxide (DMSO)] and nonswelling (xylene) solvent media were used for the reaction. Silk membranes that reacted in DMF or DMSO displayed faster reaction kinetics and attained higher weight‐gain values than fibers. The effect of the solvent on the reaction yield was in the following order: DMSO > DMF ? xylene. The Fourier transform infrared spectra of acylated silk samples showed the characteristic absorption bands of the anhydride at 2990, 2852, 1780–1700, and 1170 cm?1. The intensity of the latter band, which increased linearly with the weight gain, was used as a marker for evaluating the reaction kinetics of the samples acylated in the nonswelling medium. The moisture regain and water retention of silk fibers acylated with ODSA decreased significantly, regardless of the solvent system used. Accordingly, the water repellency increased. Acylation induced an increase in the thermal stability of the silk fibers and membranes. Fine particles adhering to the surfaces of the silk fibers acylated in xylene were detected by scanning electron microscopy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 324–332, 2003 相似文献
44.
运用TEM、TPD、XRD等技术考察了烧焦温度对异构化催化剂Pd/HM再生性能的影响。结果表明:在823K时,催化剂上金属钯粒子能重新分散,催化剂恢复活性,且稳定性不变,二次再生性也较好。 相似文献
45.
Hui Gu Rowland M. Cannon Hans J. Seifert Michael J. Hoffmann Isao Tanaka 《Journal of the American Ceramic Society》2002,85(1):25-32
The nitrogen solubility in the SiO2 -rich liquid in the metastable binary SiO2 -Si3 N4 system has been determined by analytical TEM to be 1%–4% of N/(O + N) at 1973–2223 K. Analysis of the near edge structure of the electron energy loss peak indicates that nitrogen is incorporated into the silicate network rather than being present as molecular N2 . A regular solution model with a positive enthalpy of mixing for the liquid was used to match the data for the metastable solubility of N in the presence of crystalline Si3 N4 and to adjust the computed phase diagram. The solubility of Si3 N4 in fused SiO2 is far less than reported in liquid silicates also containing Al, Mg, and/or Y. Apparently, these cations act as modifiers that break anion bridges in the silicate network and, thereby, allow further incorporation of Si3 N4 without prohibitive amounts of network cross-linking. Finally, indications emerged regarding the diffuse nature of the Si3 N4 -SiO2 interface that leads to amorphous regions of higher N content. 相似文献
46.
Schaefer-Sindlinger A. Lappas I. Vogt C. D. Ito T. Kurachi H. Makino M. Takahashi A. 《Topics in Catalysis》2007,42(1-4):307-317
This paper will give an overview about the filter development for diesel particulate emission control in automotive applications.
The material development for passenger car diesel particulate filters led to new materials like silicon carbide while for
heavy duty applications still Cordierite plays a major role. But in the future other materials might also be used for passenger
cars. This paper will show the basic difference between both applications and describe the material design in terms of filter
properties (base material, back pressure aspects, filtration efficiency, coating impact). Current application on vehicles
with catalysed soot filters (CSF) with and without oxidation catalyst will be presented. Furthermore an outlook will be given
on materials for catalysed soot filters for the future. 相似文献
47.
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Investigations on white spirit and acetone permeation resistance of modified polyamide and nylon 6 clay (MPANYC) blends and their corresponding polyethylene/MPANYC bottles were reported in this study. The white spirit and acetone permeation resistance of MPANYC sheets improve consistently with increasing NYC contents present in MPANYC resins after blending nylon 6 clay (NYC) in modified polyamide (MPA) resins. However, the order of barrier improvement of the PE/MPANYC and PE/NYC bottle specimens is not corresponding to the order of barrier improvement of the MPANYC and/or NYC barrier resins added in PE. The blow-molded PE/NYC bottle specimen exhibits similarly worse white spirit and acetone solvent permeation resistance as the PE bottle specimen, wherein no clearly formed NYC laminas but only dispersed NYC droplets or agglomerates were found on the fracture surfaces of the PE/NYC bottles. However, after blending optimum compositions of MPANYC in PE, the PE/MPANYC bottles with demarcated MPANYC laminas exhibit significantly better white spirit and acetone permeation resistance than the PE/MPA bottle, wherein the white spirit and acetone permeation rates of the PE/MPA8NYC1 bottle are about 1.3 and 1.4 times slower than those of the PE/MPA bottle, respectively. In order to understand these interesting barrier properties of PE/MPANYC and PE/NYC bottles, rheological, thermal, wide angle X-ray diffraction and morphological properties of the base MPANYC and NYC resins and their corresponding morphology present in the blow-molded bottles were investigated. 相似文献
50.