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71.
The concentrations of individual and total glucosinolates were measured in four types of Portuguese cabbage and in one hybrid white cabbage before and after cooking. Typical Portuguese culinary procedures include boiling the cabbage for 10 min but for particular kale types the leaves are first shredded then boiled for 5 min (Caldo verde). Analysis of the fresh cabbage, cooked leaves and cooking water showed that the glucosinolate content of the cabbages is reduced by more than 50%. Almost all of this loss is accounted for as intact glucosinolates in the cooking water, normally used for soups in Portugal.  相似文献   
72.
Recovering of forest biomass from Spanish hybrid poplar plantations   总被引:1,自引:0,他引:1  
Residues recovering from traditional poplar plantations for timber production are a potential relevant biomass source in Spain and other temperate countries. Three different residual biomass harvesting systems have been work-studied in order to characterize the work methods and analyze their productivity and cost. Two were oriented to branches, top and/or energy wood collection, chipping and transport using different work methods, while the other one consisted of after-logging stumps removal and shredding. Different sized and powered chippers worked in the two first cases, besides different farm tractors with trailers for off-road chips transport. Also the trucks and the loading machines were different. In the third site, a backhoe excavator removed the stumps, and a bucket loader collected them to be grinded by a shredding machine. Productivity and cost have been analyzed using IUFRO standards, providing average figures and, when possible, predictive productivity equations. Most capital-intensive equipment option has shown to be most productive, but less investment requiring system is cheaper and may be most interesting for some enterprise and plantation sizes. In addition, logistics of biomass and timber supply has been analyzed, and some indications about equipment sizing, machine annual production and relocation costs related to supply area and average plantation size are provided.  相似文献   
73.
Recently, the need for quantitative information on the spatiotemporal distribution of floating macroalgae, particularly the two species of genus Sargassum, has grown because of blooms of these species in the Gulf of Mexico and Caribbean Sea. Remote sensing is one of the most frequently used tools to assess pelagic Sargassum distribution. The purpose of this study was to implement a methodological approach to detect floating algae in an efficient and replicable manner at a moderate cost. We analyzed Landsat 8 imagery, from which we calculated four vegetation indices and one floating-algae index to implement a supervised classification, together with the bands 2 and 5, using the Random Forest algorithm. The analysis was performed monthly from 2014 to 2015 for the northeastern Yucatan Peninsula, Mexico, with a total of 91 analyzed images. The quantitative performance metrics of the classifier (overall, Kappa and Tau) were greater than 80%, whereas bands 2 and 5 as well as the atmospherically resistant vegetation index made the greatest contributions to the classifications. During summer 2015, more than 4,000 ha of Sargassum coverage per image were observed, which was substantially greater than that over the rest of the period. This approach constitutes a transferable alternative for the systematic detection of Sargassum, which enables a quantitative semi-automated time series comparison.  相似文献   
74.
Stock market automated investing is an area of strong interest for the academia, casual, and professional investors. In addition to conventional market methods, various sophisticated techniques have been employed to deal with such a problem, such as ARCH/GARCH predictors, artificial neural networks, fuzzy logic, etc. A computational system that combines a conventional market method (technical analysis), genetic programming, and multiobjective optimization is proposed in this work. This system was tested in six historical time series of representative assets from Brazil stock exchange market (BOVESPA). The proposed method led to profits considerably higher than the variation of the assets in the period. The financial return was positive even in situations in which the share lost market value.  相似文献   
75.
Amorphous and polycrystalline Sn‐doped IrO2 thin films, Ir1‐xSnxO2, are grown for the first time. Their electrical response and strength of the spin–orbit coupling are studied in order to better understand and tailor its performance as spin current detector material. These experiments prove that the resistivity of IrO2 can be tuned over several orders of magnitude by controlling the doping content in both the amorphous and the polycrystalline state. In addition, growing amorphous samples increase the resistivity, thus improving the spin current to charge current conversion. As far as the spin–orbit coupling is concerned, the system not only remains in a strong spin–orbit coupling regime but it seems to undergo a slight enhancement in the amorphous state as well as in the Sn‐doped samples.  相似文献   
76.
Multidimensional Systems and Signal Processing - In general, the fusion of visible-light and infrared images produces a composite representation where both data are pictured in a single image. The...  相似文献   
77.
78.
BACKGROUND: In Equatorial Guinea, as a result of the recent growth of the oil industry, there is an opportunity to address important public health problems through public and private initiatives. To propose effective nutrition and public health strategies, it is important first to have reliable information on the nutritional status of the population and the underlying factors affecting it. OBJECTIVE: To assess the nutritional status and the prevalence of anemia among Equatoguinean children in a nationally representative sample and to identify the risk factors associated with the nutritional problems detected. METHODS: The study was a cross-sectional survey using a multistaged, stratified, cluster-selected sample. The survey included a sociodemographic, health, and dietary questionnaire and measurement of hematocrit and anthropometric features, from which nutritional indicators based on the National Center for Health Statistics (NCHS) reference and the World Health Organization (WHO) standards were calculated. Logistic regression models were used for the multivariate analysis. A total of 552 children aged 0 to 60 months were surveyed. RESULTS: The overall prevalence of stunting (< -2 height-for-age z-scores [HAZ]) was 29.7% based on the NCHS reference and 35.2% based on WHO standards; the risk factors associated with stunting were age (p < .0001), low socioeconomic status (p = .01), and fishing by a member of the household (p = .003) The prevalence of mild anemia (hemoglobin < 110 g/L) was 69.3%, and that of moderate or severe anemia (hemoglobin < 80 g/L) was 8.3%. The only significant risk factor associated with moderate to severe anemia was low household socioeducational level (p = .01). CONCLUSIONS: Stunting and anemia are public health problems in Equatorial Guinea. Integrated strategies, including fighting poverty and improving maternal education, should be undertaken.  相似文献   
79.
Hippocampal and striatal systems are widely related to spatial tasks. Depending on the strategies used, different memory systems can be activated. In this study, the authors used the cytochrome c-oxidase technique as a functional marker of the hippocampal and dorsal striatum activity related to training in several water maze tasks. Current results show a differential participation of the hippocampal and striatal systems in navigation. When spatial information is relevant, participation of the hippocampal system is more important, and when the task is similar to a response learning one, the striatal system is more active. According to computational models, CA3 seems to be more active when the associative demand is higher, whereas CA1 and dentate gyrus activity are higher when spatial information processing is required. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
The circadian clock (CC) is a daily system that regulates the oscillations of physiological processes and can respond to the external environment in order to maintain internal homeostasis. For the functioning of the CC, the clock genes (CG) act in different metabolic pathways through the clock-controlled genes (CCG), providing cellular regulation. The CC’s interruption can result in the development of different diseases, such as neurodegenerative and metabolic disorders, as well as cancer. Leukemias correspond to a group of malignancies of the blood and bone marrow that occur when alterations in normal cellular regulatory processes cause the uncontrolled proliferation of hematopoietic stem cells. This review aimed to associate a deregulated CC with the manifestation of leukemia, looking for possible pathways involving CG and their possible role as leukemic biomarkers.  相似文献   
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