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排序方式: 共有819条查询结果,搜索用时 750 毫秒
101.
Masakazu Katsuno Noboru Ohtani Tatsuo Fujimoto Hirokatsu Yashiro 《Journal of Electronic Materials》2005,34(1):91-95
The effect of off-orientation growth has been investigated in terms of stacking fault formation during physical vapor transport
(PVT) growth of silicon carbide (SiC) single crystals on the (11
0) seed crystal surface. Occurrence of stacking fault formation is largely dependent on the direction of off-orientation,
and basal plane stacking fault density is significantly reduced by growing the crystals on a (11
0) seed crystal off-oriented toward 〈0001〉. The density of the basal plane stacking faults rapidly decreases from 100–150
cm−1 to ∼10 cm−1 as the degree of off-orientation is increased from 0 to 10 deg. The results are interpreted in the framework of microscopic
facet formation during PVT growth, and the introduction of off-orientation of seed crystal is assumed to prevent (01
0) and (10
0) microfacet formation on the (11
0) growing surface through modification of the surface growth kinetics and to suppress the stacking fault formation.
An erratum to this article is available at . 相似文献
102.
Yamanaka N Aoyama T Ikeda N Higashihara M Kamata K 《Hemodialysis international. International Symposium on Home Hemodialysis》2005,9(3):303-308
Entropy (ENT) is a newly developed measure of the complexity of heart rate variability (HRV). The aim of this study was to characterize the complexity of HRV in patients with end-stage renal disease (ESRD) and to find a possible clinical utility. Healthy subjects and patients with ESRD undergoing hemodialysis (HD) were recruited. The HD population consisted of patients with and without diabetes mellitus (DM). An electrocardiogram was recorded before HD, and blood pressure was measured during HD. The coefficients of variation of R-R intervals, high- and low-frequency components, and ratio of the low- to high-frequency components were measured as variables of HRV. The ENT was used to describe the complexity of HRV. Forty-six healthy subjects and 27 HD patients participated in this study. The ENT negatively correlated with the duration of DM (p = 0.001), systolic blood pressure (p = 0.003), and mean blood pressure (p = 0.004) before a HD session. ENT in HD patients was lower than that in healthy subjects (p < 0.01). ENT in HD patients with DM was lower than that in HD patients without DM (p < 0.01). The change in systolic blood pressure (DeltaSBP) during a HD session showed high correlations to ENT and ultrafiltration rate (UFR) of the dialyzer. The following equation was obtained: DeltaSBP = 2.25 x ENT - 2.28 x UFR - 21.27 (R2 = 0.805; p < 0.0001). ENT decreased with uremic and diabetic status. ENT also represents a possible prediction of hypotension during a HD session. 相似文献
103.
Sorbistin, a new aminoglycoside antibiotic complex of bacterial origin. III. Structure determination
M Konishi S Kamata T Tsuno K Numata H Tsukiura 《Canadian Metallurgical Quarterly》1976,29(11):1152-1162
The structures of sorbistins A1, A2, B, C and D have been determined including stereo-chemistry. Sorbistins A1, A2 and B are composed of a 4-acyl-amino-4-deoxy-D-glucose and 1,4-diamino-1,4-dideoxy-D-sorbitol, the latter compound being hitherto undescribed in literature. Sorbistins C and D have the same aglycone of 1,4-diamino-1,4-dideoxy-D-sorbitol, which is linked with D-glucose and 4-amino-4-deoxy-D-glucose, respectively, through a glycosidic bond. 相似文献
104.
Okihashi M Osakada M Uchida K Nagayoshi H Yamaguchi T Kakimoto K Nakayama Y Obana H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2010,51(5):253-257
To conduct proficiency testing for the analysis of pesticide residues in processed foods, fortified samples of retort curry and pancake were examined. In the case of retort curry, heating and mixing were necessary at the time of preparation to provide a homogenous analytical sample. A mixture of 4 carbamates and 11 organophosphorus pesticides was spiked and 14 of them showed consistent results in the samples. In the case of pancake, 10 kinds of pesticides were added to the pastry. The prepared pastry was them cooked. The relative concentrations of most of the pesticides in the pancake were not affected and all the pesticides showed consistent results in the samples. These results showed that the two tested samples were suitable for proficiency testing. 相似文献
105.
106.
Application of Highly Functional Ti-Oxide-Based Photocatalysts in Clean Technologies 总被引:1,自引:0,他引:1
Masato Takeuchi Shirou Sakai Afshin Ebrahimi Masaya Matsuoka Masakazu Anpo 《Topics in Catalysis》2009,52(12):1651-1659
Various Ti-oxide based photocatalysts such as the highly dispersed Ti-oxide species within zeolite frameworks, TiO2 nano-particles hybridized with hydrophobic zeolite adsorbents as well as visible light responsive TiO2 thin films have been successfully prepared. Characterization studies at the molecular level, such as X-ray absorption fine
structure (XAFS) and photoluminescence (PL), revealed that the highly dispersed Ti-oxide species within the nano-spaces of
zeolites possess a tetrahedral coordination and that they demonstrate unique and high performance for the photocatalytic decomposition
of NOx and the photocatalytic reduction of CO2 with H2O. A high photocatalytic reactivity for the TiO2 semiconducting photocatalysts could be achieved by blending them with hydrophobic siliceous zeolites which was equal to the
performance of TiO2 deposited with expensive Pt particles. The role of the siliceous zeolites can be described as a so-called “catch and release
effect of organic compounds”, i.e., (i) the condensation of the reactants within the hydrophobic cavities of zeolites and;
(ii) the efficient diffusion of the reactant onto the TiO2 photocatalytic sites. Furthermore, a novel photocatalytic system which can convert abundant solar energy into renewable H2 energy by the decomposition of H2O into H2 and O2 can also be achieved by using visible light responsive TiO2 thin film photocatalysts prepared by a RF-magnetron sputtering deposition method. The conversion efficiency of solar energy
into H2 energy may be estimated at ca. 0.1% from the initial rate of H2 evolution. 相似文献
107.
Takashi Kubo Masato Takeuchi Masaya Matsuoka Masakazu Anpo Atsushi Nakahira 《Catalysis Letters》2009,130(1-2):28-36
Morphologic control of Pt supported titanate nanotubes was attempted by the hydrothermal hot-pressing (HHP) technique in order to improve the handleability as a photocatalyst. The bulk of Pt-nanocrystal supported titanate nanotubes was successfully fabricated without the H2 reduction process by applying the HHP technique. The bulky Pt-nanocrystal supported titanate nanotubes possessed dense microstructures, significantly sharp distributions of mesopores, and high Brunauer–Emmett–Teller (BET) surface area. Furthermore, the bulky Pt-nanocrystal supported titanate nanotubes showed the photocatalytic degradation activities of 2-propanol aqueous solution under UV-light irradiation. 相似文献
108.
Akio Ueda Dai Kato Tomoyuki Kamata Hiroshi Uetsuka Shigeru Hirono Osamu Niwa 《Carbon》2009,47(8):1943-7599
We fabricated electrochemically stable fluorinated nano-carbon film that had an sp2 and sp3 hybrid nanocrystalline structure formed using the electron cyclotron resonance (ECR) sputtering method. This fluorinated ECR (F-ECR) nano-carbon film prepared with a short CF4 plasma treatment has a high fluorine content (F/C:0.20) and a low oxygen content (O/C:0.02) on its surface and retains its original morphology. This F-ECR nano-carbon is capable of a lower capacitance current, and a wider potential window than untreated ECR nano-carbon. The electron transfer rates at an F-ECR electrode are as high as those of untreated carbons for , whereas they are much slower than those of untreated ECR nano-carbon for Fe2+/3+ and owing to its selective sp2 fluorination. These slow electron transfer rates for Fe2+/3+ and are maintained during potential cycles due to its robust nanocrystalline structure. In contrast, these slow electron transfer rates were easily recovered for fluorinated glassy carbon under same condition. Furthermore, a smaller fluorination effect was observed for polycrystalline boron-doped diamond owing to the low reactivity of its sp3 bonds. Our ECR nano-carbon film is suitable for the effective fabrication of a fluorinated surface while maintaining a relatively active electrochemical interface and excellent stability. 相似文献
109.
Masato Takeuchi Junichi Deguchi Manabu Hidaka Shiro Sakai Kyoungja Woo Pyuck-Pa Choi Jong-Ku Park Masakazu Anpo 《Applied catalysis. B, Environmental》2009,89(3-4):406-410
The photocatalytic oxidation of gaseous acetaldehyde with O2 on commercial TiO2 nano-particles could be successfully enhanced by a simple mechanical blending with a high-silica mordenite (MOR) zeolite, the surface of which showed high hydrophobic properties. When the TiO2 nano-particles of ca. 5–20 wt% were mixed with the MOR zeolite powders in an agate mortar for only 5 min, the blended TiO2/MOR samples showed higher photocatalytic reactivity as compared to the pure TiO2 nano-particles. Since the high-silica zeolite powders are highly transparent in UV light regions, the incident UV light is effectively irradiated onto the whole part of the TiO2 nano-particles without any loss of light intensity. Furthermore, the siliceous MOR zeolite powders effectively adsorb the gaseous acetaldehyde molecules and supply them onto the surfaces of the blended TiO2 nano-particles, resulting in an enhancement of the photocatalytic reactivity. 相似文献
110.
Centrifuge model test of tunnel face reinforcement by bolting 总被引:5,自引:0,他引:5
Hirohisa Kamata Hideto Mashimo 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2003,18(2-3):205
Typical auxiliary bolting methods were tested using centrifugal models with sandy ground to confirm their strengthening effects on tunnel faces. Face bolting, vertical pre-reinforcement bolting and forepoling were tested separately, in various arrangements. Also, the experimental results were compared with the analytical results by the Distinct Element Method (DEM). Experimental results demonstrate that each bolting technique has an optimum length and arrangement to perform effectively. DEM modeling with a staggered block pattern was used to stimulate the failure states observed in the experiment. The effect of the bolting obtained from the experimental results was also confirmed by numerical simulations. 相似文献