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41.
Soya protein-lipid film, an oriental food material, as traditionally prepared is limited in methionine and has inferior physical properties. A simple modification to the traditional method of preparation, involving addition of DL-methionine and glycerol to soya milk before film formation, yielded a product which was nutritionally improved and obviated the need to reconstitute it.  相似文献   
42.
Time-intensity (TI) sweetness and bitterness curves determined for six potent sweetener combinations with and without polydextrose were compared to sucrose in shortbread cookies. Hardness, fracturability and cohesiveness of shortbreads were determined. Sweetener combinations of aspartame/cyclamate, aspartame/cyclamate/saccharin, acesulfame K/saccharin, aspartame/saccharin/acesulfame K, acesulfame K/aspartame and aspartame/saccharin gave sweetener TI profiles similar to that of sucrose. Bitterness TI profiles were similar for all potent sweetener combinations but higher than for sucrose. Polydextrose increased hardness and fracturability and decreased cohesiveness of cookies compared to those made with high potency sweeteners without polydextrose. Textural characteristics of polydextrose cookies approached those of sucrose shortbreads.  相似文献   
43.
We report the cytotoxicity of the ginseng saponin metabolite, Compound K (20‐O‐D‐glucopyranosyl‐20(S)‐protopanaxadiol, IH901) on various human leukemia cell lines. Compound K had the most effect on U937, a human monocytic leukemia cell line among the tested cell lines. Compound K‐treated U937 cells showed characteristics of apoptosis: an exposure of phosphatidylserine from the inner cell membrane to the outer cell membrane, the formation of apoptotic bodies and DNA fragmentation. Compound K induced apoptosis by up‐regulating Bax, disrupting the mitochondrial membrane potential, and by activating caspase 9 and caspase 3. Therefore, we suggest that Compound K inhibits U937 cell growth by inducing apoptosis through the up‐regulation of Bax and caspase activation.  相似文献   
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45.
The physicochemical and sensory properties of skim milk yoghurts containing poly‐γ‐glutamic acid (PGA) at different levels (0.0025, 0.005 and 0.01%) were evaluated. Addition of PGA up to 0.01% to reconstituted skim milk (11%, w/v) did not affect the growth of lactic acid bacteria or the development of titratable acidity in yoghurt, whereas full‐fat control yoghurt had reduced acid production. No changes were found in viable cell counts of PGA yoghurts during storage (4 weeks at 4 °C). The addition of PGA (0.005%) significantly decreased syneresis in skim milk yoghurt and did not cause any undesirable effects in sensory acceptability.  相似文献   
46.
The Orlu hydroelectric power plant on the River Oriège is managed by ‘hydropeaking’ and generates significant and frequent daily fluctuations in flow downstream. Observations at this site aimed to determine the impact of these variations on the aquatic environment. Surveys were carried out in June and October, upstream and about 2 km downstream of the plant, with a view to studying fish feeding habits and nutritive resources. In June, when the natural river flow was high, invertebrate populations differed very little between the two sectors. In October, after the low-water period, density and biomass were significantly lower in the downstream sector than they were upstream. Invertebrate drift was studied by taking samples every hour over a 24-hour cycle. Upstream, this drift showed a clear daily rhythm, dominated by nocturnal drift. Downstream in June, invertebrate drift was more abundant than upstream; a similar nychthemeral rhythm was apparent, but there were significant peaks during hydropeaking. In October, this daily rhythm disappeared, and drift was extremely low when river flow was low; on the other hand, a marked increase was observed during hydropeaking. Fish feeding habits were studied parallel to drift by capturing about 20 fish every four hours and analysing their stomach contents. No clear rhythm in the daily food uptake was observed. Stomach content was more abundant downstream. Lastly, the number of prey captured by fish at a given period of the day did not appear to be linked with the effective quantity of invertebrates simultaneously available in the river.  相似文献   
47.
Abstracts are not published in this journal  相似文献   
48.
The vaporization of the system MgO-Cr2O3 was studied in a vacuum of 10−5 torr (10−3N/m2) at 1500° to 1700°C using the Langmuir and Knudsen methods. It was found that the phases in the system vaporize nearly congruently and the logarithm of the vaporization coefficient, α, of MgCr2O4 increases linearly with increasing reciprocal temperature. Alpha tends to unity at a temperature near the melting point (2525±23°C). The additivity rule can be applied to the Langmuir vaporization rates on the basis of the surface area ratios of the phases in the 2-phase system MgO-Cr2O3. The enthalpies of vaporization of MgCr2O4 were 695.0 and 549.2 kcaVmol for activated and equilibrium processes, respectively.  相似文献   
49.
The advent of scanning electron microscopy has facilitated our understanding of the biology in relation to surface microstructure of many invertebrates. In recent years, interest in biomimetics and bio‐inspired materials has further propelled the search for novel microstructures from natural surfaces. As this search widens in diversity to nurture deeper understanding of form and function, the need often arises to examine rare specimens. Unfortunately, most methods for characterization of the microtopography of natural surfaces are sacrificial, and as such, place limiting constraints on research progress in situations where only a few rare specimens are known, such as the rich resources lodged in natural history museum collections. In this paper, we introduce the use of optical coherence tomography (OCT) as a noninvasive tool for bioimaging surface microtopography of crab shells. The technique enables the capture of microstructures down to micron level using low coherence near‐infrared light source. OCT has allowed surface microtopography imaging on crab shells to be carried out rapidly and in a nondestructive manner, compared to the scanning electron microscope technique. The microtopography of four preserved crab specimens from Acanthodromia margarita, Ranina ranina, Conchoecetes intermedius and Dromia dormia imaged using OCT were similar to images obtained from scanning electron microscope, showing that OCT imaging retains the overall morphological form during the scanning process. By comparing the physical lengths of the spinal structures from images obtained from OCT and scanning electron microscope, the results showed that dimensional integrity of the images captured from OCT was also maintained.  相似文献   
50.
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