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931.
The aim of the study was (i) to detect changes of dry matter, NaCl and twenty‐two free amino acids contents, pH and levels of selected microorganisms in four layers of cheese (from edge to core) during ripening and storage period and (ii) to describe the changes of the above‐mentioned parameters caused by early relocation of cheese from optimum ripening conditions to refrigeration temperatures. The number of mesophilic aerobic and facultative anaerobic bacteria and lactic acid bacteria differed significantly (P < 0.05) during the experiment dependent on the analysed layer and ripening/storage conditions. The free amino acid content differed significantly in individual analysed layers of cheese and also according to individual ripening/storage conditions. The highest content of free amino acids was found in samples stored at optimal ripening temperatures. Cheese hardness was also analysed and the lowest one was detected in samples ripened under optimal temperatures for the whole period. Early release of cheeses into storage rooms with lower temperature significantly affected properties of these products.  相似文献   
932.
Videogame-based competitions have been the target of considerable interest among researchers over the past few years since they provide an ideal framework in which to apply soft computing techniques. One of the most popular competitions is the Simulated Car Racing Competition which, thanks to the realism implemented by recent car simulators, provides an excellent test bed for the application of autonomous driving techniques. The present work describes the design and implementation of a car controller able to deal with competitive racing situations. The complete driving architecture consists of six simple modules, each one responsible for a basic aspect of car driving. Three modules use simple functions to control gear shifting, steering movements, and pedal positions. A fourth manages speed control by means of a simple fuzzy system. The other two modules are in charge of (i) adapting the driving behaviour to the presence of other cars, and (ii) implementing a basic ‘inter-lap’ learning mechanism in order to remember key track segments and adapt the speed accordingly in future laps. The controller was evaluated in two ways. First, in runs without adversaries over several track designs, our controller allowed some of the longest distances to be covered in a set time in comparison with data from other previous controllers, and second, as a participant in the 2009 Simulated Car Racing Competition which it ended up winning.  相似文献   
933.
A new algorithm is described for distributed joint diagonalization of real symmetric or complex Hermitian matrices. The approach, which is based on the Jacobi diagonalization, utilizes distribution of the computational power and memory space, minimizes the communication costs, and runs on clusters of personal computers. It further combines two-step load balancing algorithm with a standard Kalman filter to enable quick but low-cost adaptation to resource varying conditions. Theoretical analysis of its performance shows that the communication costs (when normalized by computational costs) decline linearly with the number and size of the diagonalized matrices. This is also confirmed by experimental results: the measured speedup ratio yields 42.2 when jointly diagonalizing 800 matrices of size 400 × 400 on a cluster of 50 personal computers.  相似文献   
934.
BACKGROUND: The effect of acrylic acid neutralization on the degradation of alkoxyamine initiators for nitroxide‐mediated polymerization (NMP) was studied using styrene/acrylic acid and styrene/sodium acrylate random copolymers (20 mol% initial acrylate feed concentration) as macro‐initiators. The random copolymers were re‐initiated with fresh styrene in 1,4‐dioxane at 110 °C at SG1 mediator/BlocBuilder® unimolecular initiator ratios of 5 and 10 mol%. RESULTS: The value of kpK (kp = propagation rate constant, K = equilibrium constant) was not significantly different for styrene/acrylic acid and styrene/sodium acrylate compositions at 110 °C (kpK = 2.4 × 10?6–4.6 × 10?6 s?1) and agreed closely with that for styrene homopolymerization at the same conditions (kpK = 2.7 × 10?6–3.0 × 10?6 s?1). All random copolymers had monomodal, narrow molecular weight distributions (polydispersity index M?w/M?n = 1.10–1.22) with similar number‐average molecular weights M?n = 19.3–22.1 kg mol?1. Re‐initiation of styrene/acrylic acid random copolymers with styrene resulted in block copolymers with broader molecular weight distributions (M?w/M?n = 1.37–2.04) compared to chains re‐initiated by styrene/sodium acrylate random copolymers (M?w/M?n = 1.33). CONCLUSIONS: Acrylic acid degradation of the alkoxyamines was prevented by neutralization of acrylic acid and allowed more SG1‐terminated chains to re‐initiate the polymerization of a second styrenic block by NMP. Copyright © 2008 Society of Chemical Industry  相似文献   
935.
Vegetables are rich sources of the biologically active compounds which have beneficial effects in prevention of some diseases and certain types of cancer. From the point of view of protection and health, the objective of this paper was to optimize food content in order to obtain a functional food. In order to improve the nutritive and protective properties of the product, the beetroot and carrot juices enriched with brewer’s yeast autolysate were subjected to lactic-acid fermentation with Lactobacillus acidophilus NCDO1748.  相似文献   
936.
937.
Boehmite (γ-AlOOH) nanoparticles were successfully synthesized by the two-reverse emulsion technique at 90°±1°C under constant agitation with varying Al3+ concentrations in the aqueous solution. A mixture of cyclohexane and the surfactant, sorbitan monooleate (Span 80), constituted the support solvent in the reverse emulsions. The synthesized particles were characterized by thermogravimetry, differential thermal analysis, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), particle size analysis, and transmission electron microscopy (TEM). XRD and FTIR results confirmed crystalline boehmite formation at 90°±1°C. The average particle size of boehmite was found to be 10 nm. The spherical morphology of the boehmite nanoparticles was confirmed by TEM.  相似文献   
938.
最近好像流行转型,冯小刚拍起了战争片,而星爷则开始拍“儿童片”。相比冯导的《集结号》,星爷的这次转型并不太成功,当然,这只是就电影本身而言。在商场上,星爷早已大获成功,除了票房收入,Intel的广告费、电影周边的玩偶疯卖,早已让星爷赚得盆满钵满了。  相似文献   
939.
940.
Fractionation of Co, Cu, Fe, Mn, Mo, Ni, P and Zn in extracts of buckwheat and amaranth flour in 0.02 mol·l−1 Tris-HCl (pH = 7.5) buffer was performed by SEC/ICP-MS. All metals except for Fe and Mn (both samples) and Cu (amaranth only) are concentrated in a low-molecular fraction (M r < 2 kDa). Fe is bound in a high-molecular fraction (M r > 150 kDa). The main part of Mn is present as a labile complex or an ionic form. Cu in amaranth extract is also bound in medium-molecular fractions (10 and 40 kDa) and in a high-molecular one (M r > 150 kDa). Fractions rich in trace metals were isolated using preparative-scale SEC and the organic ligands of metals were refined by immobilized metal affinity chromatography. Low content of sulphur-containing amino acids (Cys, Met) and high content of acidic amino acids (Glu, Asp) are typical for all these purified fractions. A part of Zn (buckwheat) and almost all Cu (amaranth) in the low-molecular fractions were located in phosphorus rich sub-fractions. However, all Ni (both samples), the majority of Zn (buckwheat) and all Cu (buckwheat) were found in phosphorus-less sub-fractions. No phytochelatins were found in MALDI-MS spectra of isolated ligands.  相似文献   
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