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91.
The aim of this study was to assess the influence of amaranth seeds in different doses, under conditions of oxidative stress induced by dietary fructose, on antioxidant status of selected rat tissues, erythrocytes and plasma. Fructose administration caused oxidative stress that was manifested by the increase in plasma malondialdehyde and by the decrease in the enzymatic antioxidant activity. Co-administration of amaranth seeds influenced the oxidative stress, as was evidenced by decreasing malondialdehyde in plasma and changing the activities of antioxidant enzymes (erythrocyte superoxide dismutase, catalase, and plasma glutathione peroxidase). Our findings demonstrate that amaranth seeds can act as a moderate protective agent against fructose-induced changes. Our results suggest that the antioxidative system of plasma, heart and lungs is more efficient when amaranth seeds are present in the diet.  相似文献   
92.
The present paper describes the results of experimental investigations of heat transfer and pressure drop during the condensation of the R134a and R404A refrigerants in pipe minichannels with internal diameters d = 0.31–3.30 mm. The results concern investigations of the local heat transfer coefficient and a pressure drop in single mini-channels. The results were compared with calculations according to the correlations proposed by other authors. Within the range of the examined parameters of the condensation process in mini-channels produced from stainless steel, it was established that the values of the heat transfer coefficient may be described with Akers et al. and Shah correlations within a limited range of the mass flux density of the refrigerant and the mini-channel diameter. A pressure drop during the condensation of these refrigerants is described in a satisfactory manner with Friedel and Garimella correlations. On the basis of the experimental investigations, the authors proposed their own correlation for the calculation of local heat transfer coefficient αx.  相似文献   
93.
Measurements of developing films in adiabatic high pressure steam-water flow in annular geometry have been reanalyzed and compared to a linearized film-flow model. The development rate of the outer film could be determined with good accuracy in four cases. In one case it was also possible to conclude that the inner film develops faster than the outer one. When compared to the linearized model, these observations show that the deposition rate has to be almost independent of the drop concentration at the investigated conditions. Furthermore, any significant deposition by direct impaction of drops can be excluded as it would couple the development of the two films. These conclusions are quite general and do not depend on the use of any particular correlation for the deposition or entrainment rates. Finally, a rough estimate of the deposition rate was possible, confirming that deposition rates are considerably lower at high pressure steam-water flows than in air-water flows.  相似文献   
94.
95.
Summary The action of-irradiated patulin onSaccharomyces cerevisiae OCK 2144 in liquid culture was studied. Patulin irradiated in an aqueous solution with doses ranging over 0.34–1.36 kGy inhibited the yeast growth in a proportion to the concentration of undestroyed toxin. Patulin disappearance in the growth medium occurred between 12–72 h of incubation at 30° C. The patulin content did not essentially change in the period of log phase of yeast growth which is accompanied by rapid glucose uptake.
Einfluß des -bestrahlten Patulins aufSaccharomyces cerevisiae
Zusammenfassung Es wurde die Wirkung von-bestrahltem Patulin aufSaccharomyces cerevisiae OCK 2144 in Flüssigkultur untersucht. Patulin beeinflußte nach der Bestrahlung in wäßrigen Lösungen mit Dosen von 0,34 bis 1,36 kGy das Hefewachstum entsprechend dem Toxininhalt. Der Patulinabbau im Zuchtmedium erfolgte zwischen 12 und 72 h der Inkubation bei 30 °C. Der Patulingehalt veränderte sich nicht in der logarithmischen Phase des Hefewachstums, in dem der schnelle Glucoseverbrauch erfolgte.
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96.
97.
We consider polynomial vector fields of the form and their polynomial perturbations of degree n. We present a sufficient condition that the perturbed system has an invariant surface close to the plane z = 0. We study limit cycles which appear on this surface. The linearized condition for limit cycles, bifurcating from the curves y 2x 3 + 3x = h, leads to a certain 2- dimensional integral (which generalizes the elliptic integrals). We show that this integral has a representation R 1(h)I 1 + + R e(h)I e, where R j (h) are rational functions with degrees of numerators and denominators bounded by O(n). In the case of constant and one-dimensional matrix A(x,y) we estimate the number of zeros of the integral by const n.  相似文献   
98.
Summary A new Dukat variety of strawberries was used to study the effect of irradiation combined with cold storage on their shelf life and chemical composition. Strawberries, with or without stems, were irradiated with a dose of 2.5 or 3.0 kGy within 6–10 or 20–24 h after harvesting. Results of the sensory evaluation showed that the minimum storage time for the fruits could be extended by a minimum of 9 days. If the time between harvest and irradiation was shorter, better results for storage experiments were obtained. Fruits with stems were more suitable for cold storage after irradiation than those without stems. Irradiation of strawberries did not change the titratable acidity and content of the reducing sugars. Colour intensity and ascorbic acid levels decreased in proportion to the absorbed dose and storage time.
Die Eignung von Erdbeeren der Sorte Dukat durch Bestrahlung die Lagerstabilität bei der Kaltlagerung zu verlängern
Zusammenfassung Bei der neuen Erdbeersorte Dukat wurde der Einfluß der Bestrahlung zusammen mit der Kaltlagerung auf ihre Lagerstabilität und chemische Zusammensetzung untersucht. Die Erdbeeren mit oder ohne Stiele wurden mit 2,5 und 3,0 kGy Bestrahlungsdosen innerhalb 6–10 bzw. 20–24 h nach der Ernte bestrahlt. Die sensorischen Ergebnisse haben gezeigt, daß die Lagerstabilität der Früchte um mindestens 9 Tage verlängert werden kann. Wenn die Zeit zwischen Ernte und Bestrahlung kürzer war konnten bessere Ergebnisse erzielt werden. Die Früchte mit Stiel waren zur Kaltlagerung nach der Bestrahlung besser geeignet als die ohne Stiele. Die Bestrahlung von Erdbeeren beeinflußte nicht die Titrationsacidität und den Gehalt an reduzierenden Zuckern. Die Intensität der Farbe und der Ascorbinsäuregehalt verminderten sich im Verhältnis zur Bestrahlungsdose und Lagerungszeit.
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99.
100.
The traditionally perceived function of nutrition includes supplying the consumer with the appropriate quantity and quality of substrates. As nutritional substrates, proteins are prone to spontaneously occurring non-enzymatic glycosylation (glycation) which can alter their molecular structure, making them highly bioactive. Glycated food proteins are able to modify the bacterial intestinal ecosystem, which is of great importance for the optimal usage of nutrients and maintenance of both intestinal homeostasis and balanced health status of the consumer. This study aimed to determine the impact of glycated pea proteins on the intestinal bacteria from a healthy human. The analyses were conducted with the use of experimental batch-type simulator models imitating human intestinal conditions. The glycated pea proteins affected the growth of gut commensal bacteria, particularly lactobacilli and bifidobacteria, whose levels increased significantly. There was a corresponding shift in the bacterial metabolites with increased levels of the short chain fatty acids (SCFAs); acetate, propionate lactate and butyrate. Intestinal bacteria were able to utilize these pea proteins thus indicating that the energy encrypted in glycated pea proteins, partially inaccessible for gastric enzymes, may be salvaged by gut microbiota. Such changes in microbial composition may beneficially impact the intestinal environment and exert a health-promoting effect in humans.  相似文献   
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