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1.
On the basis of the behavioral approach system (BAS) dysregulation theory of bipolar disorder, this study examined the relation between occurrence of a BAS activation-relevant life event--goal striving--and onset of hypomanic and depressive episodes and symptoms. In particular, the authors examined the relation between preparing for and completing final exams (a goal-striving event) and onset of bipolar spectrum episodes and symptoms in college students with bipolar II disorder or cyclothymia (i.e., "soft" bipolar spectrum conditions). One hundred fifty-nine individuals with either a bipolar spectrum disorder (n=68) or no major affective psychopathology (controls; n=91) were further classified on the basis of whether they were college students (i.e., completed final exams). Consistent with the BAS dysregulation theory, preparing for and completing final exams was associated with an increase in hypomanic but not depressive episodes and symptoms in individuals with a soft bipolar spectrum diagnosis. Furthermore, self-reported BAS sensitivity moderated the presence of certain hypomanic symptoms during final exams. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
In a previous paper (Mancini and Savassi, 1999), it was shown that every plane panel, used to brace tall building structures, can be easily and generally approached through the use of the continuous medium technique (CMT) (Albigés and Goulet, 1960). In that paper, following a so‐called local formulation, i.e., by deriving the governing differential equations system of the panel, in terms of u(z) panel horizontal displacement and wi columns or walls axial displacements, the equivalence (likeness) of formal mathematics, and hence of structural behaviour, between the panel composed by a pair of shear walls associated by lintel beams and another panel formed by the plane association, by pinned horizontal bars, of one shear wall and one single bay frame, was also shown. In both cases, axial deformations due to axial forces on vertical members were taken into account. In this paper, confirming those conclusions, but now following a global formulation (i.e., considering the total potential energy of each panel: strain energy plus applied load potentials), the mathematical equivalence between those two types of plane panels is again revealed by comparison of their two total potential energy analytical expressions. Additionally, based on that variational approach, the one‐dimensional finite element formulation is presented. This enlarges the possibilities of solutions for more general types of panels, like those with variable geometry or loading, without any further difficulty. The procedure, for any type of panel, can be codified in one single computer program, very similar to those used to solve plain continuous beam problems. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
3.
We have examined the applicability of this simple and effective test to polymer systems widely used in the medical industry. First, it was found that not every polymer examined exhibited a distinct onset of autocatalytic oxidation detectable by DSC. However, for cases where distinct onsets are found, powerful insights can be obtained. These included activation energy of the degradation, thermal oxidative shelf life prediction, and correlation, with product performances. Actual examples are presented to illustrate the utility of the test.  相似文献   
4.
Eddie Cheng 《Information Sciences》2007,177(22):4877-4882
We prove that when linearly many vertices are deleted in a Cayley graph generated by a transposition tree, the resulting graph has a large connected component containing almost all remaining vertices.  相似文献   
5.
Transmission Control Protocol (TCP) provides mechanisms for reliable data communications. Although it works well in wired networks, it fails to offer satisfactory performance in lossy and wireless environments. And in the multi-hop wireless infrastructure, packet delivery suffers high cumulative loss rate if traveling over multiple wireless hops. The Selective acknowledgment (SACK) is one header option that might be used to combat segment corruptions in air channels. In this paper, an alternative set of flow control mechanisms is proposed to handle high packet loss rate in a wireless medium. Using a measurement-based mechanism, sustainable segment delivery is achievable through a novel size-reduction method. Multiple segment retransmission mechanisms are introduced to reduce successive timeout events. One single byte loss is sufficient to waste all other bytes in a file received at a destination. That is, a good TCP flow control mechanism should provide a high successful file transmission completion rate, and this is set as our design goal. Through thorough simulations, our proposed multi-segment retransmission designs perform with higher successful file transfer rate and fewer timeout events than NewReno and SACK under a wide range of packet loss probabilities.  相似文献   
6.
Beer is an alcoholic beverage made from a cereal grain extract and is widely consumed in sub‐Saharan Africa and the world at large. However, beer consumption could expose consumers to mycotoxins. In this review, we appraised the different mycotoxins associated with beer contamination, elucidating their structures and incidence in cereals involved in beer production. The common mycotoxins that are found within the brewing process are reviewed. These include aflatoxin B1 (AFB1), fumonisin (FB), ochratoxin A (OTA), zearalenone (ZEA) and deoxynivalenol (DON), which are the prime contaminants in beer produced in sub‐Saharan Africa. Residual levels of <20% of AFB1, OTA and FB2 together with the transformation of ZEA (into a less toxic compound β‐zearalenol) can be achieved during the production of beers originating from Europe/America, while >50% of DON and higher ratios of FB1 can be recovered in finished beer. Adsorption is the major means of mycotoxin removal during beer production. In contrast, traditional African beer processes show no significant efficient removal of mycotoxins. This is because the prevailing environmental conditions during beer production are favourable to mycotoxigenic fungal proliferation. This subsequently leads to relatively high concentration of mycotoxins in freshly processed beer, with a possible increase during the beer shelf‐life owing to the absence of appropriate microbial stabilisation treatments in the finished processed beer. © 2019 The Institute of Brewing & Distilling  相似文献   
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8.
Renewable electric power plant development is one of the fastest-growing industries in the United States and the world. There are a significant number of investors that are entering this market, some with and some without prior energy industry experience. Developers, especially those without energy industry experience, can potentially commit serious mistakes and waste millions of dollars in their initial investment. This is primarily because interfacing with electric utilities is not a well-understood process and does not readily conform to general experience or common sense.  相似文献   
9.
The interaction between the construction market and the overall economy has attracted much attention, but few studies have investigated the influence of the property market on the construction market in terms of property price. The disaggregated data of Hong Kong’s housing and retail construction sectors are collected to investigate the impact of property price on construction output. The newly developed autoregressive distributed lag (ARDL) bounds testing approach and the error correction (EC)-based Granger causality test are employed. The bounds testing results suggest that there exist stable long-run relationships between construction output and property price for both housing and retail construction sectors. Specifically, a 1.00% increase in the housing price and retail price lead to a 0.55% and 0.42% increase in construction outputs for the two sectors respectively. In addition, the Granger causality tests confirm a distinct long-run causal flow from property price to construction output. Furthermore, the proposed ARDL approach provides an effective method for forecasting construction output.  相似文献   
10.
The role of temperature in determining the chemical stability of a waste form, as well as its leach rate, is very complex. This is because the dissolution kinetics is dependent both on temperature and possibility of different rate-controlling mechanisms that appear at different temperature regions. The chemical durability of Alumina-Borosilicate Glass (ABG) and Glass–Graphite Composite (GGC), bearing Tristructural Isotropic (TRISO) fuel particles impregnated with cesium oxide, were compared using a static leach test. The purpose of this study is to examine the chemical durability of glass–graphite composite to encapsulate coated fuel particles, and as a possible alternative for recycling of irradiated graphite. The test was based on the ASTM C1220-98 methodology, where the leaching condition was set at a temperature varying from 298 K to 363 K for 28 days. The release of cesium from ABG was in the permissible limit and followed the Arrhenius’s law of a surface controlled reaction; its activation energy (Ea) was 65.6 ± 0.5 kJ/mol. Similar values of Ea were obtained for Boron (64.3 ± 0.5) and Silicon (69.6 ± 0.5 kJ/mol) as the main glass network formers. In contrast, the dissolution mechanism of cesium from GGC was a rapid release, with increasing temperature, and the activation energy of Cs (91.0 ± 5 kJ/mol) did not follow any model related to carbon kinetic dissolution in water. Microstructure analysis confirmed the formation of Crystobalite SiO2 as a gel layer and Cs+1 valence state on the ABG surface.  相似文献   
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