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21.
Branching and pruning: An optimal temporal POCL planner based on constraint programming 总被引:2,自引:0,他引:2
A key feature of modern optimal planners such as graphplan and blackbox is their ability to prune large parts of the search space. Previous Partial Order Causal Link (POCL) planners provide an alternative branching scheme but lacking comparable pruning mechanisms do not perform as well. In this paper, a domain-independent formulation of temporal planning based on Constraint Programming is introduced that successfully combines a POCL branching scheme with powerful and sound pruning rules. The key novelty in the formulation is the ability to reason about supports, precedences, and causal links involving actions that are not in the plan. Experiments over a wide range of benchmarks show that the resulting optimal temporal planner is much faster than current ones and is competitive with the best parallel planners in the special case in which actions have all the same duration.1 相似文献
22.
We compare, in this paper, the far field radiated by two fractal distributions of current. The first one is obtained by a fractal cut following the Cantor arrangement, the second one keeps the length of each previous current element, but modifies the distance between the elements which is now taken as a constant. We establish the analytical formulations of the far field at any step n of the Cantor set. Then, we extract the array factor and we analyse and compare the following properties : convergence of the radiation pattern, wide of the main lobe, side lobes level and directivity. 相似文献
23.
Thierry Nabeth 《Datenschutz und Datensicherheit - DuD》2006,30(9):538-542
Discussing on the subject of Identity, and reaching a common understanding is sometime difficult even between people having a similar background. It represents a formidable challenge when people originate from different disciplines (such as security, law or IT), and when they have totally different backgrounds (such as academics or practitioners). This article presents how FIDIS, a Network of Excellence, is addressing this challenge 相似文献
24.
ABSTRACT: The relationship between the content of N-acetylneuraminic acid residues of micellar K-casein and acid coagulability of milk was investigated. At 30 °C, partial deglycosylation of micellar K-casein does not significantly affect the content of micellar proteins, micellar surface charge, and micellar solvation. Casein micelles modified by the release of part of the N-acetylneuraminic acid residues showed a shorter acid gelation time, a higher rate of gel strengthening, and a higher final firmness. This enhancement in the gelation ability of the neuraminidase-treated casein micelles of milk should appear as the result of increase in number of hydrophobic sites on the surface of casein micelle due to enzymatic deglycosylation of micellar K-casein. 相似文献
25.
Dounia Saifia Mohammed Chadli Salim Labiod Thierry Marie Guerra 《International Journal of Control, Automation and Systems》2012,10(3):613-622
This paper proposes a method for designing robust H?? static output feedback stabilization of Takagi-Sugeno (T-S) fuzzy systems under actuator saturation. In this paper, the input saturation is represented by a polytopic model and the modeling error is assumed a norm-bounded uncertainty. A set invariance condition for robust H?? static output feedback system under actuator saturation is first established. Then, the estimation of the largest domain of attraction for the system is formulated and solved as a Linear Matrix Inequality (LMI) optimization problem. Two examples are used to demonstrate the effectiveness of the proposed design method. 相似文献
26.
Clarisse Roblin Steve Chiumento Cdric Jacqueline Eric Pinloche Cendrine Nicoletti Hamza Olleik Elise Courvoisier-Dezord Agns Amouric Christian Basset Louis Dru Marie Ollivier Aurlie Bogey-Lambert Nicolas Vidal Mohamed Atta Marc Maresca Estelle Devillard Victor Duarte Josette Perrier Mickael Lafond 《International journal of molecular sciences》2021,22(6)
The world is on the verge of a major antibiotic crisis as the emergence of resistant bacteria is increasing, and very few novel molecules have been discovered since the 1960s. In this context, scientists have been exploring alternatives to conventional antibiotics, such as ribosomally synthesized and post-translationally modified peptides (RiPPs). Interestingly, the highly potent in vitro antibacterial activity and safety of ruminococcin C1, a recently discovered RiPP belonging to the sactipeptide subclass, has been demonstrated. The present results show that ruminococcin C1 is efficient at curing infection and at protecting challenged mice from Clostridium perfringens with a lower dose than the conventional antibiotic vancomycin. Moreover, antimicrobial peptide (AMP) is also effective against this pathogen in the complex microbial community of the gut environment, with a selective impact on a few bacterial genera, while maintaining a global homeostasis of the microbiome. In addition, ruminococcin C1 exhibits other biological activities that could be beneficial for human health, as well as other fields of applications. Overall, this study, by using an in vivo infection approach, confirms the antimicrobial clinical potential and highlights the multiple functional properties of ruminococcin C1, thus extending its therapeutic interest. 相似文献
27.
We report on a neutron scattering study of the molecular structure of a self-assembled supramolecular polymer composed of a bicopper complex within a solution of a covalent polymer (atactic polystyrene/trans-decalin). The study is achieved by putting two binary phases in contact and allowing for diffusion of both components in either phase. It is shown that the one-dimensional bicopper filaments are compatible to a high extent with the atactic polymer. These results are discussed in the light of a recently devised encapsulation process of the bicopper filaments within the fibrils of a physical network of isotactic polystyrene. 相似文献
28.
Eric Jorge Thierry Chartier Phillippe Boch 《Journal of the American Ceramic Society》1990,73(8):2552-2554
Ultrasonication is very effective in dispersing alumina and barium titanate slurries. When optimum conditions are used, very short durations (2 to 3 min) are enough to achieve well-dispersed, stable suspensions. 相似文献
29.
This study examines the incorporation of highly unsaturated n−3 fatty acids (HUFA) into triacylglycerols (TAG) of brown adipose
tissue (BAT), and their effect on the positional distribution of saturated (SFA) and of unsaturated (UFA) 16- or 18-carbon
fatty acids. To this end, rats were fed a fish oil diet for up to four weeks. The stereospecific analysis of TAG was based
on generation ofsn-1,2- andsn-2,3-acylglycerols by Grignard degradation, followed by synthesis of phosphatidic acid and specific hydrolysis with phospholipase
A2. From the end of the first week of fish oil feeding, a steady-state in the fatty acid composition of TAG in BAT was reached.
HUFA concentration increased 30-fold, mainly at the expense of n−9 UFA and of SFA. The amount of SFA decreased selectively
at position 3, where these fatty acids were progressively replaced by n−3 HUFA. By contrast, the amount of UFA decreased at
all positions, and their positional distribution was not affected. About 60% of HUFA was incorporated at position 3. Nearly
twice as much 22∶6n−3 was incorporated into TAG than had been previously observed in white adipose tissue (WAT) [Leray, C.,
Raclot, T., and Groscolas, R. (1993)Lipids 28, 279–284]. At the steady-state, the distribution of HUFA was characterized by high proportions of 22∶6n−3 and 20∶5n−3 in
position 3. Moreover, in each position of TAG, a steady level was reached rapidly (within 1 wk). It is concluded that, during
fish-oil feeding, fatty acids in TAG of BAT show characteristic time-course changes that lead to a characteristic composition
and a tissue-specific positional distribution. This suggests that adipose tissue has its own specificity in controlling the
build-up of TAG stores, which is likely to be regulated by the specificity of acylating enzymes as well as molecular rearrangements. 相似文献
30.
We present dynamic studies of surface reactions using video-Field Ion Microscopy (FIM) along with Pulsed Field Desorption
Mass Spectrometry (PFDMS). Catalytic water formation is followed using rhodium and platinum 3D field emitter crystals for
the oxidation of hydrogen with either oxygen (Rh) or NO (Pt). Strongly non-linear dynamics are observed with nanoscale spacial
resolution. For both reactions quasi-oscillatory behaviour exists under certain conditions of temperatures and partial pressures.
An influence of the probing electric field is observed and possibly essential in establishing oscillatory behaviour. Local
chemical probing of selected surface areas with up to 400 atomic surface sites proves catalytic water formation to take place.
Since water ions (H2O+/H3O+) cause image formation of the O2–H2 reaction on Rh, respective videos provide space-time resolved information on the catalytically active sites. Atom-probe data
also reveal that the surface of the Rh sample reversibly switches from a metallic to an oxidized state during oscillations.
As to the NO–H2 reaction on Pt, fast ignition phenomena are observed to precede wave fronts. After catalytic water formation, NO molecules
diffuse into emptied areas and cause high image brightness. Depending on the size of the Pt crystal, the reaction may ignite
in planes or kinked ledges along the <100> zone lines. Thus FIM provides clear experimental evidence that kinks are more reactive
than steps in the catalytic NO + H2 reaction. Pt surface oxidation occurs and has probably been underestimated in previous FIM studies. 相似文献