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51.
Zinc oxide (ZnO) nanograin and nanorod films were prepared by magnetron sputter deposition and an aqueous solution growth
method. Their surface wettability was studied in relation to their surface morphologies. While the surfaces of both films
were hydrophobic, the nanorod films exhibited higher surface hydrophobicity. A superhydrophobic surface was obtained on a
ZnO nanorod film with a water contact angle of 151 deg. Results have shown that their surface wettability was influenced by
the morphology of ZnO nanostructures, including the grain size, the length, and density of nanorods. Both types of ZnO films
showed switchable wettability under ultraviolet irradiation and dark storage. 相似文献
52.
53.
GaN蓝光LED电极接触电阻的优化 总被引:1,自引:0,他引:1
通过分析LED的工作电压和晶圆上两相邻N电极间电阻来讨论快速退火(RTA)和表面处理对GaN基蓝光LED接触电极的影响.研究了p-GaN表面处理对Ni/Au与p-GaN接触电阻的影响.结果表明,用KOH清洗p-GaN表面比用HCl清洗更能有效地改善Ni/Au与p-GaN的接触电阻.讨论了在氧和氮混合气氛下两种退火温度对P电极接触电阻的影响,当退火温度从570 ℃升到620 ℃时接触电阻升高.研究了氮气氛下不同退火温度和时间对LED电极接触的影响,发现在480 ℃下连续退火对N接触有利,但却使P接触变差,而450 ℃、10 min的氮气氛退火能同时得到较好P接触和N接触. 相似文献
54.
丁二酸改性电子墨水用球形SiO2颗粒的FTIR及XPS分析 总被引:2,自引:3,他引:2
采用丁二酸对球状亚微米级SiO2颗粒进行表面改性,以提高SiO2颗粒于四氯乙烯溶剂中的电泳性能,制备适于电子墨水用的白色电泳颗粒。利用傅立叶红外光谱(FTIR)、X射线光电子谱(XPS)和Zeta电位粒度仪,研究了丁二酸改性SiO2颗粒的表面键合情况及其在四氯乙烯溶剂中的Zeta电位变化情况。研究发现,丁二酸仅有一端的羧基与SiO2颗粒表面的羟基发生酯化反应,而且当丁二酸的用量为3g(50mL乙腈中)时,接枝于SiO2颗粒表面的丁二酸的量达到最大值,此时C1s(O—CO)/Si(原子比)有最大值为5.77×10-2。Zeta电位测试结果表明,丁二酸改性后的SiO2颗粒在四氯乙烯中的Zeta电位比改性前的SiO2颗粒提高了约5.5倍。 相似文献
55.
56.
利用高重频YAG激光作用在固体表面所产生的等离子体使工件和电极之间在电压远低于击穿阈值的条件下产生放电。实验结果显示 ,放电坑基本上呈火山坑形 ,既有单坑结构 ,也有多坑结构 ,其形貌受到放电波形、电源极性、放电介质等因素的影响。放电坑表面形貌的规律是 :①除了涂油时的阳极放电坑是单坑结构以外 ,其他条件下的放电坑都是复合多坑结构 ;②单坑结构呈火山坑形 ,坑底为圆弧形 ,熔凝物堆积在坑的边缘 ,多坑结构则是一个大的放电坑中有多个凸起尖峰 相似文献
57.
Yujun Tong Jichang Liu Zhengtian Yao Weifeng Fang 《Petroleum Science and Technology》2017,35(5):436-442
The preparation and evaluation of 30# hard grade asphalt by blending softening point hard deoil asphalt with several soft components were investigated. The results showed that the properties and proportions of blending soft components had a great influence on the properties of 30# asphalt. Chunfeng 70# asphalt and Maoming deoil asphalt were more suitable as blending soft components and their blended asphalt met the technical requirements of GB/T 15180-2010 when the proportion of hard deoil asphalt were 6–12% and 8–16%, respectively. PG grade results indicated that dynamic modulus of 30# asphalts at high temperature increased significantly, and antirutting ability was also improved notably, while the bending resistant ability at low temperature was slightly inferior to the high-grade asphalt. The results of mix performance tests showed that 30# hard grade asphalt had excellent anti–high-temperature deformation ability and preferable water stability compared with high-grade asphalts. 相似文献
58.
Hessa A. AlMulla 《Petroleum Science and Technology》2017,35(8):775-782
The aim of this study was to find new correlations to predict the properties of petroleum fractions blends. Several correlations for viscosity, smoke point, freezing point, Reid vapor pressure, aniline point, and cloud point were developed. These new correlations were assessed for their ability to predict the properties by comparing the estimated values with the experimental data as well as other correlations in literature. The developed correlations gave an absolute average deviation of 2.6 mm2/s for viscosity, 0.015 mm for smoke point, 0.05 K for freezing point, 6.47 kPa for RVP, 0.32 K for aniline point, and 0.9 K for cloud point. 相似文献
59.
中国石油化工股份有限公司洛阳分公司延迟焦化装置掺炼FCC油浆的比例稳定维持在10%以上,最高达到13.6%。掺炼FCC油浆后,延迟焦化装置的操作苛刻度降低,经济效益可观,每月可创效864万元;但石油焦和蜡油产品质量变差,石油焦挥发分质量分数下降1.25百分点,灰分质量分数上升0.15百分点,蜡油残炭质量分数上升1.19百分点,密度上升67 kg/m~3,装置燃料气、3.5 MPa蒸汽、电的单耗均上升;加热炉炉管和炉出口转油线结焦加剧,炉出口压力上升速率较掺炼油浆前增大0.015 MPa/月;出现了加热炉进料泵出口弯头、跨线阀、进料调节阀阀芯严重磨蚀等问题,装置安全运行风险急剧上升。针对存在问题提出了开展预知性维修、控制油浆固含量、进行设备材质升级、缩短检修周期、优化工艺流程等应对措施和建议。 相似文献
60.
M. T. Sinn J. A. del Alamo B. R. Bennett K. Haberman F. G. Celii 《Journal of Electronic Materials》1996,25(2):313-319
We have studied surface roughness on mismatched In0.65Al0.35As epilayers of various thicknesses on (001) InP. The sample set spans the entire range from coherently strained to completely
relaxed epilayers. As characterization tools, we have used atomic force microscopy (AFM), laser light scattering (LLS), and
variable azimuthal angle ellipsometry (VAAE). AFM reveals that the surfaces are covered by densely packed ellipsoidal islands
elongated along the [1-10] direction. The island size increases with layer thickness. Island anisotropy and the root mean square of the surface roughness
increase with increasing thickness but decrease upon full lattice relaxation. LLS intensity displays a prominent azimuthal
dependence that correlates well with the two-dimensional power spectrum of the surface topography, as predicted by theory.
VAAE reveals a sinusoidal dependence of the ellipsometric parameter Δ on azimuthal angle. The amplitude of A correlates well
with the short wavelength anisotropy of the surface power spectrum. Our work suggests that LLS and VAAE are fast, nondestructive,
sensitive techniques for characterization of surface roughness in mismatched III-V heterostructures. 相似文献