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991.
Design of a photocatalyst for bromate decomposition: surface modification of TiO2 by pseudo-boehmite
The rate of BrO3- reduction by a commercial TiO2 photocatalyst under UV illumination in an aqueous solution was increased by lowering the pH from 7 to 5. The effect is attributable to an enhancement of the electrical interaction between BrO3- and the positively charged surfaces of the TiO2 photocatalyst. The surface charge can be controlled by a surface modification of the TiO2 photocatalyst without controlling the pH of the water. In fact, the isoelectric point of surface-modified TiO2 was higher than that of the unloaded TiO2 photocatalyst, resulting in an increase in the rate of the photocatalytic reduction of BrO3- at a neutral pH. This increase is explained by an increase in the amount of adsorbed BrO3- on the photocatalyst surface. 相似文献
992.
Spatial confinement is known to induce a drastic change in the viscosity, relaxation times, and flow profile of liquids near the glass (or jamming) transition point. The essential underlying question is how a wall affects the dynamics of densely packed systems. Here we study this fundamental problem, using experiments on a driven granular hard-sphere liquid and numerical simulations of polydisperse and bidisperse colloidal liquids. The nearly hard-core nature of the particle-wall interaction provides an ideal opportunity to study purely geometrical confinement effects. We reveal that the slower dynamics near a wall is induced by wall-induced enhancement of 'glassy structural order', which is a manifestation of strong interparticle correlations. By generalizing the structure-dynamics relation for bulk systems, we find a quantitative relation between the structural relaxation time at a certain distance from a wall and the correlation length of glassy structural order there. Our finding suggests that glassy structural ordering may be the origin of the slow glassy dynamics of a supercooled liquid. 相似文献
993.
Soetikno V Watanabe K Sari FR Harima M Thandavarayan RA Veeraveedu PT Arozal W Sukumaran V Lakshmanan AP Arumugam S Suzuki K 《Molecular nutrition & food research》2011,55(11):1655-1665
Scope : We hypothesized that curcumin, a potent anti‐oxidant, might be beneficial in ameliorating the development of diabetic nephropathy through inhibition of PKC‐α and PKC‐β1 activity‐ERK1/2 pathway. Methods and results : Diabetes was induced by a single intraperitoneal injection of streptozotocin (STZ) (55 mg/kg) in rats. Three weeks after STZ injection, rats were divided into three groups, namely, normal, diabetic and diabetic treated with curcumin at 100 mg/kg/day, p.o., for 8 wk. At 11 wk after STZ injection, diabetic rats exhibited renal dysfunction, as evidenced by reduced creatinine clearance, increased blood urea nitrogen (BUN) and proteinuria, marked increases in lipid peroxidation, NOX4 and p67phox and decrease in anti‐oxidant enzyme. All of these abnormalities were significantly reversed by curcumin. Furthermore, the high‐glucose‐induced PKC‐α and PKC‐β1 activities and phosphorylated ERK1/2 was significantly diminished by curcumin. Curcumin also attenuated the expression of TGF‐β1, CTGF, osteopontin, p300 and ECM proteins such as fibronectin and type IV collagen. The high‐glucose‐induced expression of VEGF and its receptor VEGF receptor II (flk‐1) was also ameliorated by curcumin. Conclusion : These results prove that curcumin produces dual blockade of both PKC‐α and PKC‐β1 activities, which suggests that curcumin is a potential adjuvant therapy for the prevention and treatment of diabetic nephropathy. 相似文献
994.
K. Watanabe M. Masuda K. Nakamura† T. Inaba A. Noda T. Yanagida T. Yanaki 《International journal of cosmetic science》2005,27(2):143-144
Removing makeup is considered to be the first step in the skincare process. Makeup that has served its purpose is a kind of impurity that should ideally be removed completely to maximize the effects of skincare products applied afterwards. However, the use of silicone resins has significantly improved the long‐lasting property of makeup with the result that makeup can hardly be removed efficiently either with surfactant‐type cleansers like soaps or with oil‐based cleansers like liquid crystalline cleansers. Furthermore, oil‐based makeup removers do not leave the skin feeling fresh but oily, and often have been used in combination with surfactant‐type cleansers. In other words, complete makeup removal and a fresh skin feel are considered to be incompatible in conventional formulation technologies. To obtain compatible systems, we investigated the applicability of a system known as the bicontinuous phase and eventually succeeded in developing a novel system for a makeup remover. This phase can be prepared with a specific composition with a complete hydrophilic‐lipophilic balance in an oil/surfactant/water system by using cyclo‐siloxane, which dissolves silicone resin well. The bicontinuous phase has an oil‐ and water‐continuous microstructure, showing affinity for both aqueous and oily substances. This bicontinuous phase was applied to the development of a novel makeup remover. Determination of remover cap‐ability and fresh skin feel revealed that the makeup could be completely removed and that the amount of oil remaining on skin surface after wash‐off was much less than with previous oil‐based removers. The results of the sensory test also supported the finding that the remover was far superior to conventional products. This makeup remover is the first example of the application of the bicontinuous phase technology to a cosmetic product and clearly seems to provide the best conditions for subsequent skin care, meaning that it is suitable for the first step in the skincare process. 相似文献
995.
Suppressive effects of bifidobacteria on lipid peroxidation in the colonic mucosa of iron-overloaded mice 总被引:2,自引:0,他引:2
Ito M Sawada H Ohishi K Yoshida Y Yokoi W Watanabe T Yokokura T 《Journal of dairy science》2001,84(7):1583-1589
The antioxidative effects of live bifidobacteria on lipid peroxidation in the colonic mucosa were investigated. Bifidobacterium bifidum strain Yakult, which has been used for production of fermented milk, most effectively inhibited lipid peroxidation catalyzed by ferrous iron in liposomes among 10 species of bifidobacteria from human intestinal flora. Oral administration of B. bifidum strain Yakult for 2 wk significantly decreased the level of lipid peroxide (thiobarbituric acid reactive substance) in the colonic mucosa of iron-overload mice (Fe 0.07% in diet). The iron concentrations in plasma and cecum contents were not affected by administration of B. bifidum strain Yakult. Bifidobacterium bifidum strain Yakult had no chelating or incorporating activity for ferrous iron in vitro. Therefore, the antioxidative effect of B. bifidum strain Yakult in the colonic mucosa was not thought to be based on the removal of ferrous iron from the reaction system of lipid peroxidation. These results suggested that B. bifidum strain Yakult protected the colonic mucosa from oxidative injury without inhibiting iron absorption. 相似文献
996.
Watanabe T Furukawa S Kitamoto K Takatsuki A Hirata R Ogihara H Yamasaki M 《International journal of food microbiology》2005,105(2):131-137
As a non-thermal sterilization process, high-pressure carbon dioxide treatment (HPCT) is considered to be promising. The main sterilizing effect of HPCT is thought to be acidification in cytoplasm of microorganisms. We investigated the tolerance mechanism of Saccharomyces cerevisiae to HPCT with special reference to vacuolar and plasma membrane H(+)-ATPases. HPCT was imposed at 35 degrees C, 4 to 10 MPa, for 10 min. slp1 mutant defective in vacuole morphogenesis was more sensitive to HPCT than its isogenic parent. Concanamycin A, a specific inhibitor of vacuolar H(+)-ATPase (V-ATPase), at 10 microM rendered the parent more HPCT-sensitive to the level of slp1. To confirm further the contribution of V-ATPase to the tolerance against HPCT in S. cerevisiae, we compared vma1 mutant of V-ATPase with its isogenic parent for their HPCT sensitivity. vma1 mutant was more sensitive to HPCT than its parent. Addition of 10 microM vanadate, an inhibitor of plasma membrane H(+)-ATPase (P-ATPase), to the wild type strains also increased the inactivation ratio. These results clearly show that V- and P-ATPases contribute to the tolerance against HPCT in S. cerevisiae by accumulating excess H(+) from cytoplasm to vacuole and excluding H(+) outside of the cell, respectively. 相似文献
997.
Elevation of bovine serum C-reactive protein and serum amyloid P component levels by lactation 总被引:1,自引:0,他引:1
M Morimatsu A Watanabe K Yoshimatsu T Fujinaga M Okubo M Naiki 《The Journal of dairy research》1991,58(3):257-261
C-reactive protein (CRP) and serum amyloid P component (SAP), which are known to increase in sera from humans and many other animals with acute inflammation caused by infection, toxic drug administration or injury, were previously purified from bovine serum. These serum levels were determined by enzyme-linked immunosorbent assay (ELISA) using specific antiserum to bovine CRP or SAP which was prepared by immunizing rabbits and goats with each purified protein. Among 68 healthy Holstein cows, 45 non-lactating cows had levels of CRP and SAP of 20.6 +/- 1.4 and 27.6 +/- 1.3 micrograms/ml respectively; 23 lactating cows had higher levels of CRP and SAP (76.0 +/- 13.6 and 38.3 +/- 5.5 micrograms/ml respectively). In the latter group, there was a high correlation between milk yield and serum CRP levels (P less than 0.001). From these observations, it was assumed that lactation might stimulate CRP synthesis rather than SAP synthesis in bovine liver as an acute phase reaction, and that CRP might be called a lactation-associated protein. 相似文献
998.
Tsunenori Watanabe Yoshihisa MikiTakeo Masuda Hiroshi DeguchiHiroyoshi Kanai Saburo HosokawaKenji Wada Masashi Inoue 《Ceramics International》2011,37(8):3183-3192
Synthesis of the γ-Ga2O3-Al2O3 solid solutions by spray pyrolysis was examined. Spherical particles were obtained using an aqueous solution of Al(NO3)3 and Ga(NO3)3 with HNO3. For Ga-rich composition, γ-phase solid solutions were directly crystallized by the spray pyrolysis. For Al-rich composition, spray pyrolysis gave amorphous products unless a sufficient thermal energy was supplied during the spray pyrolysis. Subsequent calcination of the amorphous products gave γ-Ga2O3-Al2O3 solid solutions. However, physical properties of the solid solutions were affected by the spray pyrolysis conditions. 相似文献
999.
Yoshiaki Kano Kyohei Watanabe Takashi Kosaka Nobuyuki Matsui 《Electrical Engineering in Japan》2011,174(1):49-58
This paper proposes a new modeling approach for circuit‐field‐coupled time‐stepping electromagnetic analysis of a saturated interior permanent magnet synchronous motor (IPMSM). To predict the drive performance quickly, the proposed approach consists of a dynamic simulator based on a new analytical model of the d‐ and q‐axis magnetization characteristics (λ‐id‐iq‐θ). The model can take into account not only cross‐saturation but also the harmonics of the inductance distributions and EMF waveforms. The validity of the model is verified from suitable simulation results for the instantaneous current and torque waveforms of the IPMSM. The proposed analysis leads to a dramatic reduction in the computation time compared to circuit‐field‐coupled time‐stepping FEA, while maintaining analytical accuracy. The effectiveness of the proposed method is experimentally verified using a 10‐kW, 15,000‐rpm concentrated‐winding IPM motor. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(1): 49–58, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21024 相似文献
1000.
Kami D Takeda S Itakura Y Gojo S Watanabe M Toyoda M 《International journal of molecular sciences》2011,12(6):3705-3722
Nanoparticle technology is being incorporated into many areas of molecular science and biomedicine. Because nanoparticles are small enough to enter almost all areas of the body, including the circulatory system and cells, they have been and continue to be exploited for basic biomedical research as well as clinical diagnostic and therapeutic applications. For example, nanoparticles hold great promise for enabling gene therapy to reach its full potential by facilitating targeted delivery of DNA into tissues and cells. Substantial progress has been made in binding DNA to nanoparticles and controlling the behavior of these complexes. In this article, we review research on binding DNAs to nanoparticles as well as our latest study on non-viral gene delivery using polyethylenimine-coated magnetic nanoparticles. 相似文献