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171.
172.
Since dentistry has been identified as being a stressful profession, dentists, with the help of the members of the dental team, must attempt to achieve a relatively stress-free working environment. In addition to recognising potential occupational stressors it is important for dentists to be able to assess their emotional responses to the practice of dentistry and to arrange their daily working lives in such a way as to reduce occupational stress. This paper examines the means by which dentists may assess occupational stress as well as person-centred and/or situation-centred strategies of coping with and controlling occupational stress in general dental practice. 相似文献
173.
The routine wearing of gloves during the dental treatment of patients forms an integral part of the recommended guidelines of many authorities worldwide. Compliance has been variable but there is evidence to show that this is increasing, as are other cross-infection control measures. A survey of glove use by general dental practitioners in England and Wales was carried out in 1989. This paper reports a follow up study in 1991/2 which aimed to identify any differences that had occurred in the interim. The results indicated that there was increasing compliance with recommended cross-infection control measures, although only one fifth of respondents were found to change gloves between patients. Of those practitioners who did not change gloves between patients, half considered that blood contact was not a reason for changing gloves. Comparisons are made with compliance rates in other countries and recommendations made for further education within the dental profession on the subject of cross-infection control. 相似文献
174.
Armin Biere Edmund M. Clarke Yunshan Zhu 《Electronic Notes in Theoretical Computer Science》2001,23(2):34-45
The verification process of reactive systems in local model checking [1,7] and in explicit state model checking is[13,15] on-the-fly. Therefore only those states of a system have to be traversed that are necessary to prove a property. In addition, if the property does not hold, than often only a small subset of the state space has to be traversed to produce a counterexample. Global model checking [6,23] and, in particular, symbolic model checking [4,22] can utilize compact representations of the state space, e.g. BDDs [3], to handle much larger designs than what is possible with local and explicit model checking. We present a new model checking algorithm for LTL that combines both approaches. In essence, it is a generalization of the tableau construction of [1] that enables the use of BDDs but still is on-the-fly. 相似文献
175.
176.
Michael Burke Ron Cytron Jeanne Ferrante Wilson Hsieh 《The Journal of supercomputing》1989,3(2):71-88
This paper presents an efficient algorithm that automatically generates a parallel program from a dependence-based representation of a sequential program. The resulting parallel program consists of nested fork-join constructs, composed from the loops and statements of the sequential program. Data dependences are handled by two techniques. One technique implicitly satisfies them by sequencing, thereby reducing parallelism. Where increased parallelism results, the other technique eliminates them by privatization: the introduction of process-specific private instances of variables. Additionally, the algorithm determines when copying values of such instances in and out of nested parallel constructs results in greater parallelism. This is the first algorithm for automatically generating parallelism for such a general model. The algorithm generates as much parallelism as is possible in our model while minimizing privatization.An earlier version of this paper was presented at the First Workshop on Languages and Compilers for Vector and Parallel Machines, which was held at Cornell University in August 1988. That same year a select group of these workshop papers were published in two special issues of the journal: volume 2, numbers 2 and 3. 相似文献
177.
Chakrapani V. Varanasi Leon Chuck Lyle Brunke Jack Burke Andrew D. Chaney Paul N. Barnes 《Journal of Electronic Materials》2007,36(10):1265-1269
A simple testing method is used to compare the yield strengths (YS) of biaxially textured metallic substrates (Ni and its
alloys) presently under development for YBa2Cu3O7−x
coated conductors. This method is based on a retired ASTM D3379 tensile test standard method that was originally recommended
for single filament materials. Several common textured substrates, such as Ni, Ni-3at.%W, and Ni-5at.%W, procured from different
manufacturers, were tested using this method, and the data were compared with the values reported in the literature. A new
alloy substrate (constantan (Cu55-Ni44-Mn1wt.%)) that is biaxially textured in-house was also tested using this method, and
the YS data were compared with those of other substrates. For the substrates used in this study, the data obtained using this
method indicated that Ni substrates have YS of ∼52 MPa, Ni-3at.%W substrates have YS of ∼106 MPa, Ni-5at.%W substrates have
YS 163 MPa, and Cu55-Ni44-Mn1 wt.% substrates have YS of 74 MPa. 相似文献
178.
CP Tensen KJ Cox JF Burke R Leurs RC van der Schors WP Geraerts E Vreugdenhil H Heerikhuizen 《Canadian Metallurgical Quarterly》1998,10(11):3409-3416
Neuropeptide Y is an abundant and physiologically important peptide in vertebrates having effects on food intake, sexual behaviour, blood pressure and circadian rhythms. Neuropeptide Y homologues have been found in invertebrates, where they are very likely to play similar, important roles. Although five neuropeptide Y-receptor subtypes have been identified in mammals, none has been reported from invertebrates. Here we describe the cloning of a neuropeptide Y-receptor from the brain of the snail Lymnaea stagnalis. The identity of the receptor was deduced by expressing the neuropeptide Y-receptor-encoding cDNA in Chinese Hamster Ovary cells, which were subsequently challenged with size-fractionated Lymnaea brain extracts. An active peptide, selected on the basis of its ability to induce changes in cAMP levels, was purified to homogeneity, analysed by mass spectrometry and amino acid sequence determination, and turned out to be a Lymnaea homologue of neuropeptide Y. 相似文献
179.
We have earlier reported a higher Fcgamma-receptor (FcgammaR)-mediated generation of reactive oxygen species, measured as luminol-enhanced chemiluminescence (CL) from peripheral neutrophils in adult periodontitis patients. The aims of this study were to confirm our previous results and to elucidate the mechanism of this phenomenon by measuring CL in parallel with the intracellular production of hydrogen peroxide, after stimulation with opsonized bacteria. To determine whether the higher CL was associated with altered responsiveness to priming, the cells were preincubated with tumor necrosis factor alpha (TNFalpha) and lipopolysaccharide (LPS). While CL was significantly higher in subjects with periodontitis, there was no difference in hydrogen peroxide production between the patients and the controls, indicating that the hyperreactivity is related to the generation of other oxygen species than H2O2 and/or to processes in the outer cell membrane. The responsiveness to priming with LPS on CL was slightly but not significantly higher in the periodontitis group, suggesting that priming could be of value for distinguishing subjects with periodontitis. When assaying intracellular production of H2O2, TNFalpha and LPS had both a priming and an activating effect. There were no significant differences between the two groups. In conclusion, this study shows a higher FcgammaR-mediated CL of peripheral neutrophils from adult patients with periodontitis, thus confirming our earlier results. The hyperreactivity seems to be related to the outer cell membrane or to oxygen species other than H2O2. 相似文献
180.