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61.
Fatty acid composition and sensory characteristics of lamb carcasses from Britain and Spain 总被引:5,自引:0,他引:5
Fatty acid composition of intramuscular fat in M. Longissimus was measured in four groups of lambs representing two Spanish breeds: Rasa Aragonesa (RA) and Merino (ME) and two British lamb types: the Welsh Mountain breed (WM), whose carcasses were purchased in Spain and typical early lambs (EL) purchased in Britain. The lambs grown in Spain were concentrate fed and slaughtered at a lighter weight and lower age than those grown in Britain. The British lamb carcasses purchased in Spain were of a similar weight to the Spanish lambs but were lighter than the lamb carcasses purchased in Britain. The British lambs were grass fed. Relationships between fatty acid (FA) composition and sensory attributes were examined following sensory testing of all lambs by both British and Spanish taste panels. The production system was shown to be more important than breed in determining FA composition. British lambs had higher percentages, within total fatty acids, of 18:0, 18:3 (n-3) and long chain polyunsaturated n-3 FA and lower percentages of 18:2 (n-6) and long chain polyunsaturated n-6 FA than Spanish lambs. These differences were due to the different feeding systems used. The amounts of these FA in muscle (mg/100 g) were also different between the British and Spanish groups, not only because the British lambs had more total fat. For both taste panels, odour and flavour intensity were positively correlated with the amounts and percentages of 18:0 and 18:3 and negatively correlated with those of 18:2. This was explained by the fact that both panels gave higher odour and flavour intensity scores to the grass-fed British lamb with high 18:3 levels and lower scores to the concentrate-fed Spanish lamb with high 18:2 levels. However, 18:0 and 18:3 were positively correlated with flavour quality and overall appraisal for the British panel and negatively for the Spanish panel. Conversely, 18:2 was a positive contributor to flavour and overall preference for the Spanish panel and was negative for the British panel. The results show that the production system affects muscle fatty acid composition and the flavour of lamb. However, people's preference is determined to a large extent by their past experience. 相似文献
62.
C. Vidal-Valverde Marin Prodanov Isabel Sierra 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1997,205(6):464-469
Lentils (Lens culinaris, var. vulgaris cultivar Magda-20) were naturally fermented for 96 h at different lentil flour concentrations (79, 150 and 221 g/l) and temperatures
(28, 35 and 42°C). During fermentation, samples were taken at 24-h intervals and the changes in thiamin (vitamin B1), riboflavin (vitamin B2) and total and available niacin (vitamin B3) were investigated. Preparation of the lentil flour suspension to be fermented (i.e. the process of mixing the flour and
sterilized tap water) caused an increase of the available niacin content in all batches, while changes in thiamin and riboflavin
content were related to the conditions in which the preparation of the suspensions was carried out. The whole natural fermentation
process (from the raw state to after 96 h of fermentation), either did not affect or produced a slight decrease in the thiamin
content of lentils. In contrast, riboflavin, available niacin and total niacin contents increased throughout the 96 h period,
which ended with a 35 – 82% increase of riboflavin, a 24 – 91% increase of available niacin and a 20 – 58% increase of total
niacin. The temperature during the fermentation procedure had significant effect on the levels of thiamin and riboflavin in
fermented lentils. To obtain lentil flours with an improved amount of riboflavin and available niacin with a minimum loss
of thiamin, the natural fermentation of lentils should be carried out for 96 h at 42°C and with a lentil flour concentration
of 221 g/l.
Received: 21 February 1997 相似文献
63.
Liam Ellis Nicholas Dowson Jiri Matas Richard Bowden 《International Journal of Computer Vision》2011,95(2):154-179
This work proposes an approach to tracking by regression that uses no hard-coded models and no offline learning stage. The
Linear Predictor (LP) tracker has been shown to be highly computationally efficient, resulting in fast tracking. Regression
tracking techniques tend to require offline learning to learn suitable regression functions. This work removes the need for
offline learning and therefore increases the applicability of the technique. The online-LP tracker can simply be seeded with
an initial target location, akin to the ubiquitous Lucas-Kanade algorithm that tracks by registering an image template via
minimisation. 相似文献
64.
Claudia Bernal Monica Mesa Ligia Sierra 《Materials science & engineering. C, Materials for biological applications》2012,32(6):1380-1385
Monomodal or bimodal porous silicas with large mesopores, constituted by particles or having a monolithic (block type) morphology, respectively, are synthesized using sodium silicate as siliceous species source, cetyltrimethylammonium bromide (CTAB) as pore template and ethyl acetate (EtAc) as pH modifier. The monomodal porosity is represented by 20–30 nm pores and the bimodal one by these pores and also macropores. These characteristics are modulated in function of the CTAB and EtAc concentrations as well as the pH and hydrothermal treatment. The role of these reagents upon the porosity is rationalized. The presence of high CTAB concentration and a rather low pH decreasing rate (function of EtAc concentration and hydrothermal treatment) are essential for having the already known bimodal mesoporous silicas (BMS). On the contrary a rather high pH decreasing rate promotes the formation of the new bimodal mesoporous–macroporous silicas (BMMS) synthesized in this work, where the EtAc also plays the role of emulsion forming agent. The hydrolytic stability of the synthesized silica under aqueous conditions, at different pH values, makes these silicas good candidates for application in different areas of catalysis, especially in the enzymatic one. 相似文献
65.
66.
67.
Lucie G. Bowden Matthew J. Simpson Ruth E. Baker 《Journal of the Royal Society Interface》2013,10(88)
Cell trajectory data are often reported in the experimental cell biology literature to distinguish between different types of cell migration. Unfortunately, there is no accepted protocol for designing or interpreting such experiments and this makes it difficult to quantitatively compare different published datasets and to understand how changes in experimental design influence our ability to interpret different experiments. Here, we use an individual-based mathematical model to simulate the key features of a cell trajectory experiment. This shows that our ability to correctly interpret trajectory data is extremely sensitive to the geometry and timing of the experiment, the degree of motility bias and the number of experimental replicates. We show that cell trajectory experiments produce data that are most reliable when the experiment is performed in a quasi-one-dimensional geometry with a large number of identically prepared experiments conducted over a relatively short time-interval rather than a few trajectories recorded over particularly long time-intervals. 相似文献
68.
This paper describes a convolution-based approach to the analysis of images containing few texture classes. Segmentation of foreground and background textures, or detection of boundaries between similarly textured objects, is demonstrated. The application to industrial inspection applications is demonstrated. Near frame-rate performance on low-cost hardware is possible, since only convolution with small kernels is used. A new algorithm to optimize convolution kernels for the required texture analysis task is presented. A key feature of the paper is the industrial readiness of the techniques described. 相似文献
69.
Germán Sierra Gallego Joël Barrault Catherine Batiot-Dupeyrat Fanor Mondragón 《Catalysis Today》2010,149(3-4):365-371
LaNiO3 type perovskite was prepared by the “self-combustion” method and was used as catalyst precursor for the methane decomposition reaction at 600 and 700 °C. CH4 conversion reaches 80% at 700 °C and 65% at 600 °C using pure CH4. The yield of CNT and H2 were 2.2 gCNT g?1 h?1 and 8.2 L g?1 h?1 at 700 °C respectively after 4 h of reaction. When the reaction is prolonged to 22 h the catalytic activity decreases but the catalyst is still active, the production of hydrogen reaches 63.5 L (STP) per gram of catalyst and the production of MWCNT was equal to 17 g per gram of catalyst.Multi-wall carbon nanotubes were characterized by X-ray diffraction (XRD), surface area (BET), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Raman spectroscopy. TEM micrographs showed that MWCNT longer than 20 μm were formed with inner diameters ranging from 5 to 16 nm and outer diameters up to about 40 nm.The results obtained here clearly show that the use of the perovskite LaNiO3 as catalytic precursor is very effective for the simultaneous production of carbon nanotubes and hydrogen. 相似文献
70.
In the last years the amount of information being transmitted through communication networks has increased, and this has lead to an increased use of security protocols. The implementations of security protocols do not accurately follow the standards and this causes many malfunctions and security flaws. In this paper we will analyze the different approaches followed by the scientific community to evaluate security protocols' implementations, and will also analyze the special characteristics of security protocols, in order to deduce which are the key points for such an evaluation, how they can be evaluated and also if existing evaluation techniques can be used. 相似文献