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71.
In this work we propose a generalization of the notion of directional monotonicity. Instead of considering increasingness or decreasingness along rays, we allow more general paths defined by curves in the n-dimensional space. These considerations lead us to the notion of α-monotonicity, where α is the corresponding curve. We study several theoretical properties of α-monotonicity and relate it to other notions of monotonicity, such as weak monotonicity and directional monotonicity.  相似文献   
72.
Two graphene-like materials, obtained by thermal exfoliation and reduction of a graphite oxide at 700 and 1000 °C, were studied as active electrodes in the positive half-cell of a Vanadium Redox Flow Battery (VRFB). In particular, that obtained at 1000 °C exhibited an outstanding electrochemical performance in terms of peak current densities (30.54 and 30.05 mA cm?2 for the anodic and cathodic peaks at 1 mV s?1, respectively) and reversibility (ΔEp = 0.07 V). This excellent behavior is attributed to the restoration of sp2 domains after thermal treatment, which implies the production of a graphene-like material with a high electrical conductivity and accessible surface area. Moreover, the residual functional groups, –OH, act as active sites towards the vanadium redox reactions. This represents a significant step forward in the development of highly effective VRFB electrode materials.  相似文献   
73.
This review focuses on the application of NMR methods for understanding, at the molecular and atomic levels, the diverse mechanisms by which sugar molecules are recognised by the binding sites of lectins, antibodies and enzymes. Given the intrinsic chemical natures of sugars and their flexibility, it is well established that NMR parameters should be complemented by computational methods in attempts to unravel the structural and conformational features of the molecular recognition process unambiguously. We therefore aim here to describe new and significant advances in the knowledge of carbohydrate-protein interactions, obtained by employing state-of-the-art NMR and molecular modelling. We have not attempted to prepare an exhaustive review but have tried to focus on describing the key aspects that should be considered when tackling a problem within this research topic.  相似文献   
74.
The aim of this study was to assess the effectiveness of inoculation with a native arbuscular mycorrhizal (AM) fungus, Glomus mosseae (Nicol. and Gerd.) Gerd. and Trappe, or a filamentous fungus, Penicillium aurantiogriseum Dierckx 1901, on the establishment of Coronilla juncea L. seedlings grown in a polluted, semiarid soil. For that, root and shoot biomass, nutrient uptake, mycorrhizal colonisation and nitrate reductase (NR) and phosphatase activities were analysed. Six months after planting, the shoot biomass of C. juncea was increased only by the inoculation with G. mosseae (by about 62% compared with non-mycorrhizal plants). The shoot NR and root acid phosphatase activities were increased more by inoculation with G. mosseae than with P. aurantiogriseum inoculation. The root NR activity and foliar nutrient contents were increased only by the inoculation with the AM fungus. The root Zn and Cu decreased with the AM fungus. In conclusion, the autochthonous AM fungus was an effective inoculant with regard to stimulating growth and alleviating heavy metal toxicity for plants growing on a soil contaminated by multiple heavy metals. Inoculation with an autochthonous, filamentous fungus does not seem to be a good strategy for phytoremediation of such problematic sites.  相似文献   
75.
We present a case of eruptive collagenomas of the skin in a young girl. The typical clinical features and histology of this rare condition are described. The differential diagnosis and other types of cutaneous collagenomas are briefly discussed. A biopsy is required to confirm the excessive mature collagen which predominates in these lesions.  相似文献   
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This perspective article focuses on the recent advances in the rational design of catalyst for NH3 decomposition at different length scales, from catalyst nanoparticles to reactor design. For an overall optimum performance, all scales should be optimized in a concerted manner. The study of the mechanism of reaction has given guidelines for the catalyst design. As far as reactor design is concerned, a structured reactor is beneficial for this reaction because it minimizes the inhibiting effect of produced H2, besides other inherent advantages. This holistic optimization of catalysts is expected to pave the way for application of NH3 as H2 storage media.  相似文献   
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We investigated the relationship between maintenance bolus dose of vecuronium bromide (Vb) and the recovery time measured by TOF Guard in patients anesthetized with isoflurane (1.2-2.0%)-N2O-O2 (GOI group, n = 19) and epidural anesthesia (2% mepivacaine) plus isoflurane (0.5%)-N2O-O2 (EPI group, n = 14). In both groups, anesthesia was induced with propofol 2 mg.kg-1 and Vb 0.1 mg.kg-1 and ventilation was controlled to keep end tidal CO2 between 35-40 mmHg. When the muscle relaxation recovered to 25% of train-of four ratio (TOFR), doses of Vb 0.06, 0.04 or 0.02 mg.kg-1 were administered. Recovery time to TOFR 25% at each Vb dose (T 0.06, T 0.04 and T 0.02 respectively) was observed. T 0.02, T 0.04 and T 0.06 in GOI group were 36.7 +/- 3.2, 50.7 +/- 4.3 and 60.7 +/- 5.02 min (mean +/- SE), respectively and those in EPI group were 42.6 +/- 2.53, 52.2 +/- 2.51 and 59.9 +/- 3.22 min, respectively. There were no significant differences in the recovery time between these two groups. In both groups, although the recovery time to TOFR 25% was prolonged significantly in proportion to the increasing doses of Vb, the increase did not correlate with the dose of Vb. We suggest that frequent administration of Vb 0.02 mg.kg-1 decreases the total amount of Vb to keep TOFR within 25%.  相似文献   
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