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11.
Sabine Sonnentag 《Behaviour & Information Technology》1996,15(4):213-225
This paper describes an empirical study of software design processes in which both cognitive i.e. planning the work process, knowledge about strategies and organizational i.e. work characteristics factors were examined. Thirty-five software designers with an average professional experience of 6.6 years worked on a software design task in a laboratory setting. Thinking-aloud protocols were analysed, and additional interview and questionnaire data were gathered. It was found that software designers do very little explicit planning but have a broad knowledge of useful strategies. Results of regression analyses indicated that the amount of explicit planning and knowledge of strategies is predicted by the amount of design work to accomplish, communication and cooperation requirements, and control at work. 相似文献
12.
13.
Current Research Activities
The Swedish approach to research and development in fire protection 相似文献14.
Maria Immaculata Arifin Samia Hannaoui Sheng Chun Chang Simrika Thapa Hermann M. Schatzl Sabine Gilch 《International journal of molecular sciences》2021,22(5)
Chronic wasting disease (CWD) is a prion disease found in both free-ranging and farmed cervids. Susceptibility of these animals to CWD is governed by various exogenous and endogenous factors. Past studies have demonstrated that polymorphisms within the prion protein (PrP) sequence itself affect an animal’s susceptibility to CWD. PrP polymorphisms can modulate CWD pathogenesis in two ways: the ability of the endogenous prion protein (PrPC) to convert into infectious prions (PrPSc) or it can give rise to novel prion strains. In vivo studies in susceptible cervids, complemented by studies in transgenic mice expressing the corresponding cervid PrP sequence, show that each polymorphism has distinct effects on both PrPC and PrPSc. It is not entirely clear how these polymorphisms are responsible for these effects, but in vitro studies suggest they play a role in modifying PrP epitopes crucial for PrPC to PrPSc conversion and determining PrPC stability. PrP polymorphisms are unique to one or two cervid species and most confer a certain degree of reduced susceptibility to CWD. However, to date, there are no reports of polymorphic cervid PrP alleles providing absolute resistance to CWD. Studies on polymorphisms have focused on those found in CWD-endemic areas, with the hope that understanding the role of an animal’s genetics in CWD can help to predict, contain, or prevent transmission of CWD. 相似文献
15.
Roxane Detry Vera Van Hoed Jérôme Sterckx Catherine Deledicque Kiyotaka Sato Christophe Blecker Sabine Danthine 《European Journal of Lipid Science and Technology》2021,123(1):2000155
Developing trans-free alternative fat solutions suitable for specific applications remains a challenge in edible fats and other domains. This is particularly true for palm oil-based puff pastry margarines, which suffer from post crystallization problems, leading to dramatic loss of functionality. This research is aimed at investigating the influence of triacylglycerol (TAG) compositions of palm oil-based puff pastry margarines on the physical properties of the fat crystal network, which determine the functionality of such products. Three model puff pastry margarines are produced at pilot scale under the same crystallization conditions. They share the same fatty acid composition and close solid fat content (SFC) profiles, whereas the proportions of major TAG (tripalmitoylglycerol (PPP), 1,3-di-palmitoyl-2-oleoylglycerol (POP), 1,2-di-palmitoyl-3-oleoylglycerol (PPO), 1,2-dioleoyl-3-palmitoylglycerol (POO)) are different. Polymorphism, melting profile, hardness, microscopic structures, and baking performance (puffing effect) of the model fats are examined during a period of 6 months. The following results are obtained: 1) The TAG composition significantly influences the post crystallization processes occurring in palm oil-based margarines. 2) High amounts of POP show negative influences. 3) The proportions of POP, PPO, and PPP should be carefully balanced to prevent detrimental crystal network rearrangements, leading to textural modifications (hardness increase) and significant reduction in baking performance. Practical Applications : The results presented in this work could be helpful for edible fat products developers, especially for roll-in fat applications. This research provides an overview of the relevant properties to study for the assessment of puff pastry margarine functionality. It also highlights the importance of ensuring long-term stability of palm oil-based fat products. Finally, it emphasizes that certain combinations of fat materials should be avoided to maintain the quality of palm oil-based puff pastry margarines. 相似文献
16.
Sabine Caré 《Cement and Concrete Research》2003,33(7):1021-1028
In order to determine the influence of aggregates on chloride ion ingress, mortar specimens were cast with different aggregate size distribution and the same aggregate volume content. One side of the specimen was in contact with alkaline solution containing sodium chloride. The process of chloride ingress is due to diffusion. The effect of the interfacial transition zone (ITZ) around aggregate and of the tortuosity due to aggregates have been taken into account for interpreting the experimental data obtained. These two competing effects have been quantified by using the theory of composite materials. It appears that the diffusion coefficient varies as a function of the ITZ volume content and of the tortuosity. 相似文献
17.
Desislava Bögner Frederike Schmachtl Björn Mayr Christopher P. Franz Sabine Strieben Gregor Jaehne 《臭氧:科学与工程》2019,41(2):105-117
Recirculating Aquaculture Systems (RAS) reduce water consumption by efficient filtration to maintain appropriate levels of accumulating compounds and sludge. Sludge is mechanically separated by drum filters and disposed of to the detriment of overall system water budgets. Dissolved nitrogen compounds are reduced via nitrification–denitrification filters, requiring commercial external carbon sources. The reuse of sludge after ozone pre-treatment may represent the next step in RAS optimization. The present study analyzes the content of sludge from RAS and tests ozonation as a pre-treatment for recycling as carbon source. The dissociative effect of ozone and the physicochemical changes due to ozonation lead to a significant increase in soluble carbon availability. Predominantly long-chain fatty acid (FA) (saturated and unsaturated) with 16 and 18 carbon atoms independently of the treatment were found in the profiles. Saturated FA concentrations in solution increased after 20, 40, and 60 min ozonation. The solid content of the sludge was practically unaffected by ozonation in terms of FA profile: only saturated FA slightly increases after 40 min treatment. The implications of these findings for denitrifying bacteria are discussed.
Abbreviations: Recirculating Aquaculture Systems (RAS); Advanced Oxidation Processes (AOPs) 相似文献
18.
Sabine Braipson-Danthine Claude Deroanne 《Journal of the American Oil Chemists' Society》2006,83(7):571-581
Several oils and fats often used for the industrial preparation of European shortenings were blended in binary systems. The
equilibrium (after 48 h at 15°C) solid fat contents (SFC; determined by pulsed NMR spectroscopy) were measured and plotted
against blend composition. SFC of the blends resulted from the SFC of each fat for the considered temperature as well as the
type of interaction existing between those fats (namely, ideal behavior, monotectic interaction, eutectic interaction, and
so on). The type of relationship fitted was dependent on the kind of interaction: Linear relationships were found for total
compatibility between fats, and polynomial-type (order 2) relationships were found for fats exhibiting incompatibility. Some
corresponding ternary oils and fats blends were also prepared and analyzed. Selected relationships (regression equations of
the fitted curves) obtained for binary blends were combined in order to calculate the SFC of the corresponding ternary blends.
Experimental values were generally close to predicted ones. The representation of SFC as a function of composition is interesting
as it allows one to determine rapidly and easily the type of molecular interaction between two fats and also to determine
equations that can be combined to calculate easily the SFC of corresponding ternary blends crystallized in the same way with
a good accuracy. The texture (hardness) of several binary and ternary blends was also measured. The combination of the results
obtained for SFC with the results obtained for the hardness of binary blends allows the prediction of the hardness of a corresponding
ternary blend under the same conditions. 相似文献
19.
20.
Sabine Krist Stefanie Bail Heidrun Unterweger Martin B. Ngassoum Ahmed M. Mohagir Gerhard Buchbauer 《European Journal of Lipid Science and Technology》2006,108(7):583-588
Shea butter is used as an edible vegetable fat in many African countries. It can be utilized as a substitute or complete replacement for cocoa butter in various applications and plays an important role in traditional African medicinal practice. Although detection of volatile compounds by solid‐phase micro‐extraction gas‐chromatography mass‐spectroscopy (SPME‐GC‐MS) is a very reliable and reproducible technique, which can be used as an important part of authenticity checking, production monitoring and contamination detection, no published data about volatile compounds of shea butter are available so far. In this investigation, the characteristic volatiles in the headspace of original African shea butter samples were identified by using SPME‐capillary‐GC coupled to a mass selective detector. Almost 100 different volatile components were identified, e.g. fatty acids, saturated and unsaturated aldehydes and ketones, terpenes, and typical Maillard reaction products such as methylfuranes and pyrazines. Furthermore, the samples have been olfactorily evaluated by a panel of professional flavorists and trained analytical chemists. It can be stated that variations in processing conditions of shea butter result in considerable differences in the composition of headspace volatiles, detected by SPME‐GC‐MS and human olfaction. 相似文献