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排序方式: 共有999条查询结果,搜索用时 15 毫秒
991.
Yota Takamura Kengo Hayashi Yusuke Shuto Satoshi Sugahara 《Journal of Electronic Materials》2012,41(5):954-958
A high-quality Co2FeSi (CFS)/SiO
x
N
y
/Si tunnel junction was fabricated, in which the SiO
x
N
y
barrier layer was formed by radical oxynitridation of an Si(100) substrate and the CFS electrode was formed by silicidation
of an Fe/Co/amorphous-Si multilayer deposited on the barrier layer. The ultrathin SiO
x
N
y
barrier layer completely blocked diffusion of Co and Fe atoms into the Si substrate during rapid thermal annealing (RTA)
for the silicidation. X-ray diffraction investigations clarified that the CFS film on the ultrathin SiO
x
N
y
barrier layer exhibited a highly (110)-oriented texture structure and that the film had the L21 structure with a high degree of L21 order. High resolution cross-sectional transmission electron microscopy investigations revealed that the CFS/SiO
x
N
y
interface was atomically flat and that the crystal lattice of the CFS film was directly grown on the SiO
x
N
y
surface without degradation of the crystallinity at the interface. 相似文献
992.
Ikushima S Tateishi Y Kanai K Shimada E Tanaka M Ishiguro T Mizutani S Kobayashi O 《Journal of Bioscience and Bioengineering》2012,113(4):496-501
Yeast plays a capital role in brewing fermentation and has a direct impact on flavor and aroma. For the evaluation of competent brewing strains during quality control or development of novel strains it is standard practice to perform fermentation tests, which are costly and time-consuming. Here, we have categorized DNA markers which enable to distinguish and to screen brewing strains more efficiently than ever before. Sequence analysis at 289 loci in the genomes of six bottom fermenting Saccharomyces pastorianus strains revealed that 30 loci contained single nucleotide polymorphisms (SNPs). By determining the nucleotide sequences at the SNP-loci in 26 other S. pastorianus strains and 20 strains of the top fermenting yeast Saccharomyces cerevisiae, almost all these strains could be discriminated solely on the basis of the SNPs. By comparing the fermentative phenotypes of these strains we found that some DNA markers showed a strong association with brewing characteristics, such as the production of ethyl acetate and hydrogen sulphide (H2S). Therefore, the DNA markers we identified will facilitate quality control and the efficient development of brewing yeast strains. 相似文献
993.
Extracted lipids obtained from black and red rices were analysed by high-performance liquid chromatography (HPLC), for endogenous tocochromanols. The molecular species and fatty acid (FA) distribution of triacylglycerols (TAG) isolated from these total lipids were analysed by a combination of AgNO3 thin-layer chromatography (TLC) and gas chromatography (GC), and were investigated in relation to the content of endogenous tocochromanols. With a few exceptions, the predominant tocols were γ-tocotrienol and α-tocopherol, followed by α-tocotrienol (red) and γ-tocopherol (black) with much smaller amounts of β-, δ-tocopherols and δ-tocotrienol. The lipids of these rices were comprised mainly of TAG (76.4–80.5%), free FA (7.2–9.8%), and phospholipids (3.5–3.6%), whilst other components were present in minor proportions (0.1–4.1%). The principal FA components were palmitic (16:0), oleic (18:1n − 9) and linoleic (18:2n − 6) acids. Fifteen different TAG molecular species were detected and quantified by successive applications of AgNO3-TLC and GC. The major TAG components were S2M (7.0–7.8%), SM2 (12.6–12.9%), M3 (15.7–16.5%), SMD (23.5–23.7%), SD2 (5.7–5.8%), M2D (9.3–9.8%), MD2 (8.1–8.6%) and D3 (5.8–7.4%) (where S, M, D, and T denote a saturated FA, a monene, a diene, and a triene, respectively). The results suggested that these rice lipids contain large amounts of nutraceuticals with proven positive health effects. 相似文献
994.
Kohei Kamiya Wakako Hamabe Shogo Tokuyama Ken Hirano Toshiko Satake Yuko Kumamoto-Yonezawa Hiromi Yoshida Yoshiyuki Mizushina 《Food chemistry》2010
During the course of our studies to develop new uses for the Noni (Morinda citrifolia) root, 10 anthraquinones, rubiadin (1), rubiadin 1-methyl ether (2), lucidin (3), damnacanthol (4), 1,3-dihydroxy-2-methoxymethylanthraquinone (5), 3-hydroxy-1-methoxy-2-methoxymethylanthraquinone (6), nordamnacanthal (7), damnacanthal (8), sorandidiol (9) and morindone (10), were isolated. Compounds 5, 6, 7, 8 and 10 exhibited remarkable inhibition against the activities of animal pols, and compound 10 was the strongest inhibitor in the anthraquinones investigated. Among mammalian pols, compound 10 inhibited the pol activities of A- (pol γ), B- (pols α, δ and ε) and Y- (pols η, ι and κ) families, but did not influence the activities of X-family pols (pols β, λ and terminal deoxynucleotidyl transferase). The tendency of pol inhibition showed a positive correlation with the suppression of human colon cancer cell HCT116 growth. These results suggested that the Noni root containing anthraquinones may be used as an anticancer functional food. 相似文献
995.
Specific response of osteoblast-like cells on hydroxyapatite layer containing serum protein 总被引:3,自引:0,他引:3
Kizuki T Ohgaki M Ichinose S Nakamura S Hashimoto K Toda Y Yokogawa Y Yamashita K 《Journal of materials science. Materials in medicine》2006,17(9):859-867
Accelerations of bone-like apatite deposition and cell growth on an electrically polarized ceramic hydroxyapatite have been
reported. A relationship between these phenomena was investigated in a previous report, and then it was suggested that osteoblast-like
cell’s (MC3T3-E1) growth had relevance to the mineral growth. The effect of the formed apatite layer especially appeared to
be on the cell adhesion. The acceleration of cell proliferation on the polarized HAp has been shown using fibroblastic cell
(L929) and nerve cell (SK-N-SH) lines, therefore the effect of the layer on L929 and SK-N-SH was investigated to support the
mechanism of acceleration of cell proliferation by polarization of HAp. In this study, the effect of the bone-like apatite
layer was not confirmed on L929 cell’s growth. On the other hand, the acceleration of nerve cell’s proliferation was confirmed
on the formed apatite layer. However, the remarkable improvement of the cell adhesion of SK-N-SH was not confirmed on the
apatite layer. Consequently, it was considered that the bone-like apatite containing serum protein obtained by the coprecipitation
of bone-like apatite and serum protein has a pronounced role only in the activity of osteoblast-like cells. 相似文献
996.
Itano Y Bandow H Takenaka N Saitoh Y Asayama A Fukuyama J 《The Science of the total environment》2007,379(1):46-55
We investigated the relationships between ambient O(3) concentrations and the concentrations of its precursors, NO(x) and NMHC, in Osaka, Japan. The levels of O(x)' (where [O(x)']=[O(3)]+[NO(2)]-0.1x[NO(x)] where the last term accounts for primary emissions of NO(2)) were uniform within the city even in the photochemically active season. We suggested that NO oxidation by peroxy radicals was a minor contributor, and that oxidation of locally emitted NO by background O(3) in the city was the primary control on NO(2) concentrations. Ozone concentrations increased linearly from 1985 to 2002 at a rate of 0.6 ppbv/yr, even though O(x)' concentrations remained constant after the mid 1990s. The trend for O(x)' concentrations could not be explained in terms of an increase in local O(3) production, and the trend was found to reflect background O(3) concentrations in Japan. There was a clear relationship between the NO(2)/O(x)' ratio and NO(x) concentration: the ratio decreased with decreasing NO(x) concentration. As a consequence, O(3) increased with decreasing NO(x) concentration. The reduction of NO(x) emissions was deemed to be an important factor for the recent trend of increasing O(3) concentrations in Osaka City. 相似文献
997.
Katsuyoshi Ebe Kazurou Harada Yoshiyuki Ishihara Toshiyuki Todaka 《Electrical Engineering in Japan》2000,132(4):53-61
A new analytical approach to the finite element calculation of torque in motors including eccentric rotor, based on the Maxwell stress method, is proposed in this paper, where the effects due to eccentricity on the cogging torque and the torque characteristics with regard to the speed are confirmed. A brushless dc motor is employed as an analytical model for two kinds of eccentricity. Consequently, in the case of eccentric motors, the unbalanced radial force functions as the repulsive force against rotation which causes the reduction of average torque, and two kinds of eccentric motors have the same tendency regarding the effects on the torque. This proposed approach is applicable to any kind of motor including eccentric rotor. © 2000 Scripta Technica, Electr Eng Jpn, 132(4): 53–61, 2000 相似文献
998.
This paper presents experimental results of lightning surges incoming into a customer due to lightning to an antenna of the customer, a pole and a ground nearby the customer, and briefly discusses lightning current distribution in the customer, a distribution line and a telephone line. Based on experimental results, modeling of each component is explained, and EMTP simulations are carried out. The ground voltage rise is represented by a mutual resistance between grounding electrodes. EMTP simulation results have been observed to agree qualitatively with the measured results, and it becomes possible to investigate lightning surges and current distribution in a customer by an EMTP simulation. 相似文献
999.
Raw sago starch digesting amylase was obtained from Penicillium brunneum No. 24. with strong ability to digest sago starch granules. The crude enzyme from this strain contains CMC-ase and avicelase. The specific activity of the enzyme did not increase proportionally with purification. We tried combination of our purified enzyme with other hydrolytic enzymes as a means of improving the hydrolysis of sago starch granules. Addition of cellulase at the initial stage of the hydrolyzation process resulted in an increase in the ability of raw starch digesting amylase to digest sago starch granules. Adding 10 unit/g starch of cellulase. followed of our purified raw starch digesting amylase in small portion at various time intervals was found effective in the hydrolysis of untreated sago starch granules. The treatment resulted in a convertion rate of untreated sago starch granules to glucose near to complete after 120h enzymes reaction, and was also effective in reducing the reaction time of hydrolysis of treated sago starch granules. This process showed that mainly glucose was produced. 相似文献