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101.
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The role of emotion and its associated psychophysiology have received little systematic attention in studies of psychopathology. In the present study, dysthymic and control subjects with high or low fear levels were compared on a task involving anticipation of pleasant and unpleasant slides to evaluate whether dysthymic subjects would demonstrate differential affective processing. Dysthymic subjects were found to differ from controls in several psychophysiological measures, though not in ratings of the slides or in behavioral performance. Although dysthymic subjects showed normal or heightened initial reactions to emotionally significant warning stimuli, results suggest that they withdrew and ceased affective processing as the actual emotional stimulus approached. Response mobilization processes supporting normal overt behavior appear to be intact, but aspects of the orienting response may be dysfunctional in dysthymia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Controlling Spatiotemporal Mechanics of Supramolecular Hydrogel Networks with Highly Branched Cucurbit[8]uril Polyrotaxanes 下载免费PDF全文
Cindy Soo Yun Tan Ji Liu Alexander S. Groombridge Steven J. Barrow Cécile A. Dreiss Oren A. Scherman 《Advanced functional materials》2018,28(7)
Attempts to rationally tune the macroscopic mechanical performance of supramolecular hydrogel networks through noncovalent molecular interactions have led to a wide variety of supramolecular materials with desirable functions. While the viscoelastic properties are dominated by temporal hierarchy (crosslinking kinetics), direct mechanistic studies on spatiotemporal control of supramolecular hydrogel networks, based on host–guest chemistry, have not yet been established. Here, supramolecular hydrogel networks assembled from highly branched cucurbit[8]uril‐threaded polyrotaxanes (HBP‐CB[8]) and naphthyl‐functionalized hydroxyethyl cellulose (HECNp) are reported, exploiting the CB[8] host–guest complexation. Mechanically locking CB[8] host molecules onto a highly branched hydrophilic polymer backbone, through selective binary complexation with viologen derivatives, dramatically increases the solubility of CB[8]. Additionally, the branched architecture enables tuning of material dynamics of the supramolecular hydrogel networks via both topological (spatial hierarchy) and kinetic (temporal hierarchy) control. Relationship between macroscopic properties (time‐ and temperature‐dependent rheological properties, thermal stability, and reversibility), spatiotemporal hierarchy, and chain dynamics of the highly branched polyrotaxane hydrogel networks is investigated in detail. Such kind of tuning of material mechanics through spatiotemporal hierarchy improves our understanding of the challenging relationship between design of supramolecular polymeric materials and their complex viscoelasticity, and also highlights a facile strategy to engineer dynamic supramolecular materials. 相似文献
104.
J. J. Heijnen W. A. Enger A. Mulder P. A. Lourens A. A. Keijzers F. W. J. M. M. Hoeks 《Starch - St?rke》1986,38(12):419-428
From pilot experiments (0,3–3,6 m3) and full scale application (300 m3) it is shown that the improved anaerobic fluid bed technology represents a very reliable and compact high-rate technology for the purification of highly fluctuational industrial wastewater. A two-stage process (acidification/methanation) appeared to have advantages with respect to process stability as well as purification capacity. On full scale the average purification capacity, reached six months after start-up, was 28 kg COD/m3 day (based on the volume of the methane reactor), with peaks of 50 kg COD/m3 day. Further increases in capacity may be expected in the future. 相似文献
105.
Lucas Veuthey Alessandro Aliotta Debora Bertaggia Calderara Cindy Pereira Portela Lorenzo Alberio 《International journal of molecular sciences》2022,23(5)
Procoagulant platelets are a subtype of activated platelets that sustains thrombin generation in order to consolidate the clot and stop bleeding. This aspect of platelet activation is gaining more and more recognition and interest. In fact, next to aggregating platelets, procoagulant platelets are key regulators of thrombus formation. Imbalance of both subpopulations can lead to undesired thrombotic or bleeding events. COAT platelets derive from a common pro-aggregatory phenotype in cells capable of accumulating enough cytosolic calcium to trigger specific pathways that mediate the loss of their aggregating properties and the development of new adhesive and procoagulant characteristics. Complex cascades of signaling events are involved and this may explain why an inter-individual variability exists in procoagulant potential. Nowadays, we know the key agonists and mediators underlying the generation of a procoagulant platelet response. However, we still lack insight into the actual mechanisms controlling this dichotomous pattern (i.e., procoagulant versus aggregating phenotype). In this review, we describe the phenotypic characteristics of procoagulant COAT platelets, we detail the current knowledge on the mechanisms of the procoagulant response, and discuss possible drivers of this dichotomous diversification, in particular addressing the impact of the platelet environment during in vivo thrombus formation. 相似文献
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Shoham Ben-David Cindy Eisner Daniel Geist Yaron Wolfsthal 《Formal Methods in System Design》2003,22(2):101-108
Over the past nine years, the Formal Methods Group at the IBM Haifa Research Laboratory has made steady progress in developing tools and techniques that make the power of model checking accessible to the community of hardware designers and verification engineers, to the point where it has become an integral part of the design cycle of many teams. We discuss our approach to the problem of integrating formal methods into an industrial design cycle, and point out those techniques which we have found to be especially effective in an industrial setting. 相似文献
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109.
Bilezikjian LM Blount AL Donaldson CJ Vale WW 《Reproduction (Cambridge, England)》2006,132(2):207-215
Activins, as members of the transforming growth factor-beta superfamily, control and orchestrate many physiological processes and are vital for the development, growth and functional integrity of most tissues, including the pituitary. Activins produced by pituitary cells work in conjunction with central, peripheral, and other local factors to influence the function of gonadotropes and maintain a normal reproductive axis. Follistatin, also produced by the pituitary, acts as a local buffer to bind activin and modulate its bioactivity. On the other hand, inhibins of gonadal origin provide an endocrine feedback signal to antagonize activin signaling in cells that express the inhibin co-receptor, betaglycan, such as gonadotropes. This review highlights the pituitary roles of activin and the mechanisms through which these actions are modulated by inhibin and follistatin. 相似文献
110.
Meays CL Broersma K Nordin R Mazumder A Samadpour M 《Environmental science & technology》2006,40(17):5289-5296
Nonpoint source fecal contamination is a concern for drinking water supplies worldwide. In this study, 4812 E. coli isolates were classified to source. Results of this experiment show that the fecal coliform (FC) counts varied by year, month, and site, for each of the watersheds sampled. For both years, the lowest FC counts tended to be at the highest elevation sites followed by the drinking water intake sites at the lowest elevation. The highest FC counts tended to be at the mid-elevation sites on BX, Deer, and Duteau Creeks. The sources of E. coli varied significantly with stream for 2003 and 2004 (P < 0.001, df = 39), although the main sources of E. coli (avian, deer/elk, canine, rodent, bovine, and bear) tended to be similar between watersheds. The dominant sources of E. coli changed from 2003 (avian, deer/elk, and canine) to 2004 (avian, bovine, and rodent). It is important to look at the results of more than 1 year of source tracking data to get a better picture of the dominant sources within a watershed. Overall, wildlife was the largest contributor of E. coli to the watersheds in both 2003 (> 84%) and 2004 (> 73%). 相似文献