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71.
The influences of heat treatment and test condition on the microstructure and stress rupture properties of a Ni-Mo-Cr-Fe base corrosion-resistant superalloy have been investigated in this paper. Optical microscope and scanning electron microscope were employed for the microstructure observation, and X-ray diffraction, electron probe micro-analyzer, and transmission electron microscope were used for phase determination. It was found that the grain size increased and the volume fractions of initial M6C carbides decreased along with the increase in solution treatment temperature. When tested at 650 °C/320 MPa, the stress rupture lives decreased with the increase in solution treatment temperature, but the stress rupture lives increased slightly at first and then decreased for the samples solution heat treated at 1220 °C when tested at 700 °C/240 MPa. The elongations showed the descendent trends under these two conditions. The stress rupture life and elongation for the aged samples all showed a noticeable improvement at 650 °C/320 MPa, but there was no noticeable improvement at 700 °C/240 MPa. The reasons can be attributed to the grain size, test conditions, and the initial and secondary carbides. 相似文献
72.
库车坳陷中新生界天然气成藏动力学研究 总被引:3,自引:0,他引:3
库车坳陷是塔里木盆地北部一近东西走向的狭长坳陷,以中新生代地层为主。地层压实排出水离心流区位于拜城凹陷和阳霞凹陷,克拉苏-依奇克里克构造带、东秋里塔克构造带和塔北前缘隆起带为越流泄水区。库车坳陷在早第三纪-库车早期主要为油藏、凝析油气藏形成时期;库车晚期-第四纪西域期是气藏的主要形成时期。天然气经短距离侧向汇聚,通过沟通源岩和圈闭的断裂垂向富集。在强烈的构造挤压和气体充注条件下,被具有很好封闭性的下第三系膏盐岩严密封闭,形成异常高压气藏。下伏三叠系-侏罗系源岩的沉积埋藏水、粘土矿物脱出水沿断裂带伴随天然气向浅部越流,在构造顶部形成相对低矿化度的地下水化学特征。 相似文献
73.
Zhou Zhixin Shao Chenning Zheng Haonan Zhou Huimin Yang Xin Lou Xiongwei Li Jian Hui Guohua Zhao Zhidong 《Wireless Networks》2020,26(4):2797-2808
Wireless Networks - Utility tunnel is one of the important infrastructures for the planning and building of smart city. It is of great significance to improve the efficiency of maintenance and... 相似文献
74.
75.
Gold/1-butyl-3-methylimidazolium hexafluorophosphate (Au/[Bmim][PF6]) nanofluids containing different stabilizing agents were fabricated by a facile one-step chemical reduction method, of which
the nanofluids stabilized by cetyltrimethylammonium bromide (CTABr) exhibited ultrahighly thermodynamic stability. The transmission
electron microscopy, UV-visible absorption, Fourier transform infrared, and X-ray photoelectron characterizations were conducted
to reveal the stable mechanism. Then, the tribological properties of these ionic liquid (IL)-based gold nanofluids were first
investigated in more detail. In comparison with pure [Bmim][PF6] and the nanofluids possessing poor stability, the nanofluids with high stability exhibited much better friction-reduction
and anti-wear properties. For instance, the friction coefficient and wear volume lubricated by the nanofluid with rather low
volumetric concentration (1.02 × 10-3%) stabilized by CTABr under 800 N are 13.8 and 45.4% lower than that of pure [Bmim][PF6], confirming that soft Au nanoparticles (Au NPs) also can be excellent additives for high performance lubricants especially
under high loads. Moreover, the thermal conductivity (TC) of the stable nanofluids with three volumetric fraction (2.55 ×
10-4, 5.1 × 10-4, and 1.02 × 10-3%) was also measured by a transient hot wire method as a function of temperature (33 to 81°C). The results indicate that the
TC of the nanofluid (1.02 × 10-3%) is 13.1% higher than that of [Bmim][PF6] at 81°C but no obvious variation at 33°C. The conspicuously temperature-dependent and greatly enhanced TC of Au/[Bmim][PF6] nanofluids stabilized by CTABr could be attributed to micro-convection caused by the Brownian motion of Au NPs. Our results
should open new avenues to utilize Au NPs and ILs in tribology and the high-temperature heat transfer field. 相似文献
76.
A ZnO photonic amorphous diamond nanostructure was successfully synthesised using a feather barb of the Rosy-Faced Lovebird as supporting template via a facile sol-gel process. Different from ordered structures, an isotropic PBG around 500 nm was evidenced from reflectance spectra and an optical metallurgical microscopy image, which overlaps with the visible emission peak of ZnO. As a result, the inhibition of visible emission inside the PBG and the enhancement of UV emission at the PBG edges have both been observed, which is independent from the incident angle. Moreover, the rapid thermal annealing can also help improve the crystallinity of ZnO and raise the UV/visible emission ratio without affecting the structure. These results can be very useful for the study of the modification of the optical emission properties of ZnO and other semiconductor materials as well as research on ZnO random lasing. 相似文献
77.
Abhishek JayswalXiang Li Anand ZanwarHelen H. Lou Yinlun Huang 《Computers & Chemical Engineering》2011,35(12):2786-2798
In the design of chemical/energy production systems, a major challenge is to identify the bottleneck issues and improve its sustainability effectively. Due to the multi-dimensional feature of sustainability, how to account for the impacts of various design factors and the cause-and-effect relationships can be very difficult. This paper will present a sustainability root cause analysis method based on the combination of Pareto Analysis and Fishbone diagram. The sustainability of the process is assessed incorporating economic, environmental, societal and efficiency concerns.This methodology is able to help the designers focus the attention on the most important fundamental causes, discover opportunities for sustainability improvement and provide critical guidance to design for sustainability. The efficacy of this methodology will be demonstrated through a case study on a biodiesel production technology. 相似文献
78.
Cathodic reactions, specially the oxygen and hydrogen activities, have been extensively investigated on carbon steel in simulated fuel-grade ethanol (SFGE) environments using cathodic potentiodynamic polarization and electrochemical impedance spectroscopy. Under normal conditions, oxygen reduction is the major cathodic reaction for carbon steel in SFGE. Hydrogen evolution, confirmed by hydrogen permeation test, is activated by de-aeration and at much higher cathodic overpotential. The dissociation of acetic acid in SFGE enhances the proton related cathodic reactions. Water in ethanol can increase the proton dissociation rate, resulting in a higher cathodic current density. At potentials close to free corrosion potential, the reduction of surface oxidized products contributes to the cathodic activities in SFGE. Based on this study, the possible effects of cathodic reactions on corrosion of carbon steel in SFGE are also discussed. 相似文献
79.
9-Amino epi-quinine was used as a ligand in the atom transfer radical polymerization (ATRP) for the first time, and high monomer conversion as well as small polydispersity could be obtained. The 9-amino epi-quinine-containing organosilane was synthesized and immobilized onto three different silica supports, i.e., fumed SiO2, SBA-15, and MCM-48, followed by complexing with CuBr. With the MCM-48 supported catalyst, polymerization of methyl methacrylate achieved high monomer conversion, small polydispersity, and low residual copper content in the product. This heterogeneous catalyst could also be recycled effectively. 相似文献
80.