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YOUNG-NAM KIM SEONG-IL HEO MYEONG-HYEON WANG 《Journal of Food Processing and Preservation》2009,33(1):87-104
Fibrinolytic, antigenotoxic and immunomodulating properties of chungkukjang were evaluated. The purified fibrinolytic enzyme was characterized as an alkaline serine protease with molecular weight of 22 kDa determined by fibrin zymography and stable over pH range 6.0–10.0 below 50C. The comet assay showed that N-methyl-N ' -nitro-N-nitrosoguanidine (MNNG)-induced DNA damage level (190.8 AU) in 3T3 cells was considerably decreased to 121.2 AU with chungkukjang extracts (CB) showing 49.7% of protection. Incubation of the 3T3 cells with CB significantly reduced the cytotoxicity of MNNG. [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay revealed that the addition of CB enhanced the proliferation of RAW 264.7 (mouse leukemic monocyte macrophage cell line) macrophages up to about 150% of the control levels. RAW 264.7 macrophages incubated with CB induced a strong increase in nitric oxide (NO), tumor necrosis factor -α (TNF-α) and interleukin-1α (IL-1α) with a dose-dependent manner. After 24 h incubation with 1 mg/mL of CB, NO, TNF-α and IL-1α showed the highest production of 511, 2.46 and 0.258 ng/mL, respectively. 相似文献
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The new measurement scheme of IP performance metrics is proposed for the mobile network in heterogeneous wireless network environment. In the proposed scheme, when Mobile Nodes (MNs) inside the mobile network needs to understand the condition of multiple communication paths outside the mobile network, they can get IP performance metrics, such as delay, jitter, bandwidth, packet loss, etc., irrespective of the presence or absence of measurement functionality. At the same time, the proposed scheme does not require the MN to be involved in measuring IP performance metrics. The Multihomed Mobile Router (MMR) with heterogeneous wireless interfaces measures IP performance metrics on behalf of the MNs inside the mobile network. Then, MNs can get measured IP performance metrics from the MMR using L3 messages. The proposed scheme can reduce burden and power consumption of MNs with limited resource and battery power since MNs don't measure IP performance metrics directly. In addition, it can reduce considerably traffic overhead over wireless links on multiple measurement paths since signaling messages and injected testing traffic are reduced. 相似文献
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ABSTRACT: This research explores whether homeownership leads to increased individual social capital among low‐ to moderate‐income families. Social capital refers to social resources a person can access through contacts with others in his or her social networks. We theorize that homeownership can motivate interactions with others in one's neighborhood and therefore build social capital. Using a sample of low‐ and moderate‐income homeowners and a matched sample of renters, we collect data on overall social resources and neighborhood‐specific social resources. We find that homeowners have more total social capital resources and more neighborhood social capital resources than renters. Neighborhood group involvement has an indirect effect on social capital, but explains only a small amount of the influence of homeownership. These findings hold when controlling for household‐level and neighborhood‐level sociodemographic variables, as well as when using statistical models that account for endogeneity. Based on this evidence, we conclude that homeownership gives people access to social capital via increased social ties to others. We discuss the implications of this finding for housing policy and suggest new directions for research on social capital. 相似文献
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The use of repeater for the support of high rate data transmission and the extension of cell coverage is imperative for the Wibrc system,which based on the IEEE 8M.16e standardization.Generally,if the separation between transmitting and receiving antennas isnot sufficient,the oscillation of repeater and the interference due to the feedback signals from original transmitted signal may be ocerur.Hence,the Interference Cancellation System(ICS)should be implemented as the important part of the repeater system far the mobile cellular systems in order to eliminate unwanted signals from the corruptW signals in the receiver.In this paper,we propose an adaptive technique for the Least Mean Square(LMS)-based interference cancellation methods by changing the step size according to the variation of channel environment in order to improve the performance degradation which oceuurs by using the fixed step size approach.Simrlatim results show that the proposed sclxme attains a little lower Berafor Rate(BER)performance and much faster convergence speed compared to the conventional LMS-based interference cancellation techniques.The proposed scheme can be applied to other Orthogonal Frequency Division Multiple(OFDM)-based cellular systems and also be expected to achieve a similar performance improvement to W17-advanced system,which is called as the next generation mobile communication standards. 相似文献
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Roughness coefficient and its uncertainty in gravel-bed river 总被引:1,自引:0,他引:1
Manning's roughness coefficient was estimated for a gravel-bed river reach using field measurements of water level and discharge,and the applicability of various methods used for estimation of the roughness coefficient was evaluated.Results show that the roughness coefficient tends to decrease with increasing discharge and water depth,and over a certain range it appears to remain constant.Comparison of roughness coefficients calculated by field measurement data with those estimated by other methods shows that,although the field-measured values provide approximate roughness coefficients for relatively large discharge,there seems to be rather high uncertainty due to the difference in resultant values.For this reason,uncertainty related to the roughness coefficient was analyzed in terms of change in computed variables.On average,a 20%increase of the roughness coefficient causes a 7% increase in the water depth and an 8% decrease in velocity,but there may be about a 15% increase in the water depth and an equivalent decrease in velocity for certain cross-sections in the study reach.Finally,the validity of estimated roughness coefficient based on field measurements was examined.A 10% error in discharge measurement may lead to more than 10% uncertainty in roughness coefficient estimation,but corresponding uncertainty in computed water depth and velocity is reduced to approximately 5%.Conversely,the necessity for roughness coefficient estimation by field measurement is confirmed. 相似文献