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151.
Preparation and properties of CuInS2 thin film prepared from electroplated precursor 总被引:1,自引:1,他引:1
Yoshio Onuma Kenji Takeuchi Sumihiro Ichikawa Yasunari Suzuki Ryo Fukasawa Daisuke Matono Kenji Nakamura Masao Nakazawa Koji Takei 《Solar Energy》2006,80(1):132-138
Thin CuInS2 films were prepared by sulfurization of Cu/In bi-layers. First, the precursor layer was electroplated onto the treated surface of Mo-coated glass. Observation of the cross-section prepared by focused ion beam (FIB) etching revealed that the void-free film was initially formed on the top surface of the precursor layer and continued to grow until the advancing front of the film reached the Mo layer. The nucleation of voids near the bottom of the CuInS2 film followed. To determine whether the condition of the Cu/In alloy influences the CuInS2 quality we investigated the Cu/In alloy state using FIB. We found that the annealed precursor of low Cu/In ratio (1.2) has several voids in the mid position in the layer compared with Cu-rich precursor (1.6). The cross-sectional view of the Cu-rich absorber layer is uniform compared with the low copper absorber layer. Thin film solar cells were fabricated using the CuInS2 film (Cu/In ratio: 1.2) as an optical absorber layer. It was found that the optimization of a sulfurization period is important in order to improve the cell efficiency. We have not yet obtained good results with high Cu-rich absorber because of a blister problem. This blister was found before sulfurization. So, we are going to solve this blister problem before sulfurization. 相似文献
152.
Daisuke Watanabe Keishi Nishio Yoshio Sakka Masataka Ohgaki Ian J. Davies Tomohiro Umeda Seiichiro Koda Kiyoshi Itatani 《Journal of Materials Science》2011,46(6):1956-1962
High-density β-calcium orthophosphate (β-Ca3(PO4)2, also called β-tricalcium phosphate: β-TCP) ceramics with submicrometer-sized grains were fabricated using a pulse-current
pressure firing route. The maximum relative density of the β-TCP compacts was 98.7% at 1050 °C and this was accompanied by
a translucent appearance. The mean grain size of the β-TCP compacts increased slightly with temperature to reach 0.78 μm at 1000 °C. However, upon further increasing the firing
temperature to 1050 °C the mean grain size increased significantly to 1.6 μm. The extent of plastic deformation during tensile
testing was examined at temperatures between 900 and 1100 °C using a strain rate in the range 9.26 × 10−5 to 4.44 × 10−4 s−1. The maximum tensile strain achieved was 145% for a test temperature of 1000 °C and strain rate of 1.48 × 10−4 s−1 and this was attributed to the relatively high density and small grain size. 相似文献
153.
In this study, microbial precipitation of carbonate was observed using high microbial urease activity, and it was found that the ratio of Mg/Ca affected the types of crystals produced. Without Mg2+, calcite was produced using only CaCl2, while the presence of Mg produced Mg-calcite, magnesite and/or possibly dolomite of round, spherical or fibrous shapes, depending on reaction time, pH and Mg/Ca ratio. The carbonate produced contributed to the development of cementation for sands. The presence of Mg showed a relatively strong cementation of the carbonate. 相似文献
154.
High‐Yield Preparation,Versatile Structural Modification,and Properties of Layered Cobalt Hydroxide Nanocones 下载免费PDF全文
Xiaohe Liu Renzhi Ma Yoshio Bando Takayoshi Sasaki 《Advanced functional materials》2014,24(27):4292-4302
A low‐cost oil bath synthetic route is presented to produce uniform and highly crystalline layered cobalt hydroxide nanocones (NCs) intercalated with dodecyl sulfate anions (C12H25OSO3?, DS?). A new exfoliating procedure, by gradually unravelling/unzipping these NCs through heat treatment in formamide‐water binary solution, is developed to prepare unilamellar nanosheets. Moreover, the NCs can be readily modified with various inorganic or organic anions via a conventional anion‐exchange process at ambient temperature. The exchanged product, for example, NO3?–intercalated NCs, can be more easily and rapidly transformed into cobalt oxides (e.g., Co3O4 and CoO) than the original DS?–intercalated form while retaining a conical feature. Both the cobalt hydroxide NCs and exfoliated nanosheets are electrochemically redoxable, exhibiting a Faradaic pseudocapacitive behavior. The magnetic measurements further reveal both antiferromagnetic behaviors for transformed Co3O4 and CoO NCs. Their Néel temperature values are lower than those of bulk oxides due to finite size and geometric confinement effect. The peculiar conical feature of NCs with a hollow interior and tunable layer spacing, as well as exfoliated unilamellar nanosheets with all surface area exposed, may show promise for potential applications in electrochemical energy storage and magnetic devices. 相似文献
155.
Cuiling Li Bo Jiang Hungru Chen Masataka Imura Liwen Sang Victor Malgras Yoshio Bando Tansir Ahamad Saad M. Alshehri Satoshi Tominaka Yusuke Yamauchi 《Nano Research》2016,9(6):1752-1762
Mesoporous Au films consisting of a network of interconnected Au ligaments around ultra-large pores were found to exhibit a promising electrocatalytic activity towards sluggish reactions. Mesoporous Au films with pore sizes up to 25 nm were successfully fabricated using a polymeric micelle approach. A superior catalytic activity of the mesoporous Au films towards methanol oxidation was confirmed, which was thoroughly analyzed and compared with that of other Au materials. An intrinsic investigation on the high catalytic activity revealed that the superior performance of the as-prepared mesoporous Au film was related to its unique atomic structures around the mesopores with well-crystallized facets and several step/kink sites on the Au surfaces. These findings showcase a strategic and feasible design for preparing highly active Au-based catalysts that could be used as promising candidates in electrocatalytic applications. 相似文献
156.
Sota H Yoshimine H Whittier RF Gotoh M Shinohara Y Hasegawa Y Okahata Y 《Analytical chemistry》2002,74(15):3592-3598
Despite high theoretical sensitivity, low-cost manufacture, and compactness potentially amenable to lab-on-a-chip use, practical hurdles have stymied the application of the quartz crystal microbalance (QCM) for aqueous applications such as detection of biomolecular interactions. The chief difficulty lies in achieving a sufficiently stable resonance signal in the presence of even minute fluctuations in hydrostatic pressure. In this work, we present a novel versatile planar sensor chip design (QCM chip) for a microliter-scale on-line biosensor. By sealing the quartz resonator along its edges to a flat, solid support, we provide uniform support for the crystal face not exposed to solvent, greatly decreasing deformation of the crystal resonator under hydrostatic pressure. Furthermore, this cassette design obviates the need for direct handling when exchanging the delicate quartz crystal in the flow cell. A prototype 27-MHz sensor signal exhibited very low noise over a range of flow rates up to 100 microL/min. In contrast, signals obtained from a conventional QCM sensor employing an O-ring-based holder were less stable and deteriorated even further with increasing flow rate. Additional control designs with intermediate amounts of unsupported undersurface yielded intermediate levels of stability, consistent with the interpretation that deformation of the crystal resonator under fluctuating hydraulic pressure is the chief source of noise. As a practical demonstration of the design's high effective sensitivity, we readily detected interaction between myoglobin and surface-bound antibody. 相似文献
157.
158.
Yoshio Hasegawa Chun-Xiang Feng Yong-Cai Song Zi-Lie Tan 《Journal of Materials Science》1991,26(13):3657-3664
Polycarbosilanes containing titanium alkoxide as pendant groups (atom ratio Ti/Si = 0.07 and 0.15) were synthesized. These polymers were melt-spun and then heat-treated in a vacuum, in oxygen or ammonia gas flow, resulting in Si-Ti-C-O, Si-Ti-0 and Si-Ti-O-N fibres, respectively. The pyrolysis process of the polymer is discussed in connection with the mechanical properties and the structure of the fibre. At high heat-treatment temperatures, -SiC and TiC (in Si-Ti-C-O fibre), anatase (in Si-Ti-O fibre) and TiN (in Si-Ti-O-N fibre) crystallized, which may be closely related to the decomposition of the Si-O-Ti bond in the fibre. 相似文献
159.
N Maruyama T Katsube Y Wada MH Oh AP Barba De La Rosa E Okuda S Nakagawa S Utsumi 《Canadian Metallurgical Quarterly》1998,258(2):854-862
Beta-conglycinin, one of the dominant storage proteins of soybean, is a trimer composed of three subunits, alpha, alpha' and beta. All subunits are N-glycosylated and alpha and alpha' contain extension regions in addition to the core regions common to all subunits. Non-glycosylated individual subunits and deletion mutants (alpha(c) and alpha'(c)) lacking the extension regions of alpha and alpha' were expressed in Escherichia coli. All recombinant proteins were purified to near homogeneity and appeared to have the correct conformation, as judged by CD, density-gradient centrifugation and gel-filtration profiles, indicating that the N-linked glycans and extension regions are not essential for the folding and the assembly into trimers of beta-conglycinin. Density-gradient centrifugation, gel-filtration and differential scanning calorimetry profiles of the recombinant proteins and the native beta-conglycinin indicated that the N-linked glycans and extension regions contribute to the dimension of beta-conglycinin but not to the density and the thermal stability. Comparing the solubilities of the individual subunits with those of deletion mutants, only the alpha and alpha' subunits were soluble at lower ionic strength (mu < 0.25) at around the pH value of the endoplasmic reticulum. This suggests that the extension regions play an important role in the prevention of aggregation in the endoplasmic reticulum in analogy with the N-linked glycans. 相似文献
160.
Isamu Moriguchi Masakuni Honda Taro Ohkubo Yoshio Mawatari Yasutake Teraoka 《Catalysis Today》2004,90(3-4):297-303
Mesoporous silica and mesoporous metallosilicates with Al, Ti and Fe as foreign metal species were successfully synthesized by the rapid room temperature method. Mesoporous metallosilicates with low contents of foreign metals possessed high surface area (Sa), large mesopore volume (Vmp) and highly ordered hexagonal mesoporous structure. Increases in foreign metal contents caused disordering the mesoporous structures and lowering the Sa and Vmp values. Bleaching of aqueous methylene blue (MB) by mesoporous silica and metallosilicates was investigated. Mesoporous aluminosilicate and ferrosilicate with cation-exchangeable ability showed the excellent property for the adsorption of MB of cationic dye, while mesoporous ferrosilicate and titanosilicate which absorbed UV lights catalyzed the photocatalytic decomposition of MB under UV-illumination. 相似文献