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71.
Effects of the antiosteoblastogenesis factor Semaphorin 4D (Sema4D), expressed by thrombin-activated platelets (TPs), on osteoblastogenesis, as well as osteoclastogenesis, were investigated in vitro. Intact platelets released both Sema4D and IGF-1. However, in response to stimulation with thrombin, platelets upregulated the release of Sema4D, but not IGF-1. Anti-Sema4D-neutralizing monoclonal antibody (mAb) upregulated TP-mediated osteoblastogenesis in MC3T3-E1 osteoblast precursors. MC3T3-E1 cells exposed to TPs induced phosphorylation of Akt and ERK further upregulated by the addition of anti-sema4D-mAb, suggesting the suppressive effects of TP-expressing Sema4D on osteoblastogenesis. On the other hand, TPs promoted RANKL-mediated osteoclastogenesis in the primary culture of bone-marrow-derived mononuclear cells (BMMCs). Among the known three receptors of Sema4D, including Plexin B1, Plexin B2 and CD72, little Plexin B2 was detected, and no Plexin B1 was detected, but a high level of CD72 mRNA was detected in RANKL-stimulated BMMCs by qPCR. Both anti-Sema4D-mAb and anti-CD72-mAb suppressed RANKL-induced osteoclast formation and bone resorptive activity, suggesting that Sema4D released by TPs promotes osteoclastogenesis via ligation to a CD72 receptor. This study demonstrated that Sema4D released by TPs suppresses osteogenic activity and promotes osteoclastogenesis, suggesting the novel property of platelets in bone-remodeling processes.  相似文献   
72.
Principal component analysis was applied to spectral luminous efficiencies determined by the heterochromatic brightness matching by 51 and 70 observers for the field size. 2° and 10°, respectively, which were used to derive the CIE Vb,2(Λ) and Vb,10(Λ). Four principal components were found to explain the individual variation. the two deviation indices were introduced by slightly modifying the first and second principal scores and they were effectively used to specify individual variations and to predict the spectral luminous efficiency curve. Equations were derived to predict these two deviation indices as functions of luminous efficiencies at two wavelengths, 460 and 640 nm in the case of 2° field and 470 and 630 mm in 10° field. the luminous efficiency curves thus predicted by the two deviation indices fitted very nicely to the experimentally determined luminous efficiency curves of all the observers. A way to utilize the deviation indices in practice where observers play an important role is proposed to avoid some confusion that may take place because of individual variation.  相似文献   
73.
Summary Liquid crystalline side-chain polysiloxanes were prepared without metal complex catalyst. Mesogenic groups such as cholesteryl, 4-cyano-4-biphenyl and 4-methoxy-4-biphenyl group were introduced into polysiloxane by esterification and from DSC measurements they were compatible with other liquid crystalline polysiloxanes reported previously.  相似文献   
74.
TAG (MLM) with medium-chain FA (MCFA) at the 1,3-positions and long-chain FA (LCFA) at the 2-position, and TAG (LMM) with LCFA at the 1(3)-position and MCFA at 2,3(1)-positions are a pair of TAG regioisomers. Large-scale preparation of the two TAG regioisomers was attempted. A commercially available FFA mixture (FFA-CLA) containing 9-cis, 11-trans (9c, 11t)- and 10t,12c-CLA was selected as LCFA, and caprylic acid (C8FA) was selected as MCFA. The MLM isomer was synthesized by acidolysis of acyglycerols (AG) containing two CLA isomers with C8FA: A mixture of AG-CLA/C8 FA (1∶10, mol/mol) and 4 wt% immobilized Rhizomucor miehei lipase was agitated at 30°C for 72 h. The ratio of MLM to total AG was 51.1 wt%. Meanwhile, LMM isomer was synthesized by acidolysis of tricaprylin with FFA-CLA: A mixture of tricaprylin/FFA-CLA (1∶2, mol/mol) and 4 wt% immobilized R. miehei lipase was agitated at 30°C for 24 h. The ratio of LMM to total AG was 51.8 wt%. MLM and LMM were purified from 1,968 and 813 g reaction mixtures by stepwise short-path distillation, respectively. Consequently, MLM was purified to 92.3% with 49.1% recovery, and LMM was purified to 93.2% with 52.3% recovery. Regiospecific analyses of MLM and LMM indicated that the 2-positions of MLM and LMM were 95.1 mol% LCFA and 98.3 mol% C8 FA, respectively. The results showed that a process comprising lipase reaction and short-path distillation is effective for large-scale preparation of high-purity regiospecific TAG isomers.  相似文献   
75.
People get cataract in their eyes when they age. The color perceived by the senile cataract eyes desaturates because of the environment light that scatters in the eyes by the hazy crystalline lenses. We investigated the effect of the desaturation on brightness of objects in terms of the equivalent lightness , which is composed of the achromatic lightness and the chromatic lightness . If the color desaturates, becomes smaller and consequently becomes smaller in the cataract eyes. with and without cataract experiencing goggles at room illuminances to cover mesopic to photopic level was measured. Red, yellow, green, and blue patches of size 2° × 2° arc of the visual angle were investigated with the direct heterochromatic brightness matching between the color patches and a gray scale. Both took about the same value. with goggles was then transferred to the final where the matching gray scale was observed without goggles to express the equivalent lightness of cataract eyes by the gray scale perceived by normal eyes. with goggles was lower than without goggles by about 10 L* units in all the four colors. This reduction was almost equal to the reduction of L* by the reduced transmittance of the goggles showing that there was no effect of color desaturation. The color appearance in the color patches was measured by the elementary color naming method, and the results clearly showed the color desaturation with goggles implying decrease of . We concluded that the scattered environment light compensated the decrease of to keep the brightness of stimuli unchanged. © 2011 Wiley Periodicals, Inc. Col Res Appl, 38, 267–276, 2013  相似文献   
76.
77.
New rotary molecular machines (1 and 2) were synthetically constructed from two distinct porphyrin-based rotors, a cerium(IV) bis(porphyrinate)s double-decker (CeDD) and a porphyrinatorhodium(III)-based rotor. These rotors are adjacently mounted on rotational axes aligned to near vertical as resembling the bevel-gear-shaped structure. Structural study using NMR analysis reveals that these distinct rotors are connected through a coordination bond between rhodium(III) and a pyridyl group. At temperature from 193 to 393 K, each rotor represents rotational motion driven by heat fluctuation without decomposition into the corresponding precursors in dichloromethane-d 2 and tetrachloroethane-d 4. Importantly, the mechanical interaction between the teeth of these rotors is strongly dependent on the central metal atom in a DD rotor and the teeth structure in a porphyrinatorhodium(III)-based rotor. Understanding such relationship between the chemical structures and mechanical interaction is of importance for generating cooperative motion in the hybrid machinery system.  相似文献   
78.
The graft polymerization of various monomers onto PVA has been studied by radical polymerization mechanism. Successful grafting of acrylonitrile (AN), acrylamide (AAm), acrylic acid, methyl methacrylate, and vinyl acetate was reported by using chemical (Minoet al., 1959; Ide, 1961; Maskimov et al., 1965) and radiation (Misra et al., 1987) methods. On the other hand, less attention has been paid to ionic graft polymerization. Sasson and Zilkha reported on grafting formaldehyde onto potassium-metallated PVA (Sasson and Zilkha, 1969). Galin studied grafting of AN and propane sulfone onto sodium-metallated PVA (Galin, 1971). We used the same anionic system for the polymerization of AAm (Ikeda and Suzuki, 1980).  相似文献   
79.
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully.  相似文献   
80.
We report the initial results of GaAs and GaInP solar cells grown by all solid-state molecular-beam-epitaxy (MBE) technique. For GaAs single-junction solar cell, with the application of AlInP as the window layer and GaInP as the back surface field layer, the photovoltaic conversion efficiency of 26% at one sun concentration and air mass 1.5 global (AM1.5G) is realized. The efficiency of 16.4% is also reached for GaInP solar cell. Our results demonstrate that the MBE-grown phosphide-contained III-V compound semiconductor solar cell can be quite comparable to the metal-organic-chemical-vapor-deposition-grown high-efficiency solar cell.  相似文献   
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