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11.
Two exotic fruits (Snake fruit and Mangosteen) were characterized by polyphenols, proteins and antioxidant potentials and by their influence on plasma lipids and antioxidant activity in rats fed cholesterol. The content of polyphenols (14.9±1.5 and 9.2±0.8 mg GAE g−1) and antioxidant potential (46.7±4.7 and 72.9±7.4 μmol TE g−1) in Snake fruit was significantly higher than in Mangosteen (P<0.05). Twenty male Wistar rats were divided into four dietary groups: Control, Chol, Chol/Snake and Chol/Mangosteen. After 4 weeks of the experiment diets supplemented with Snake fruit and to a lesser degree with Mangosteen significantly hindered the rise in plasma lipids and hindered a decrease of antioxidant activity. Changes were found in fibrinogen fraction, such as solubility and mobility by the number of protein bands detected in SDS-electrophoresis: Chol/Snake differed from Chol/Mangosteen. In conclusion, Snake fruit and Mangosteen contain high quantity of bioactive compounds, therefore positively affect plasma lipid profile and antioxidant activity in rats fed cholesterol-containing diets. Such positive influence is higher in rats fed diet with added Snake fruit.  相似文献   
12.
GC and GC‐MS analysis of fruit volatile oil of star anise (Illicium verum Hook) showed the presence of 25 components which account for the 99.9% of the total amount. The major components were trans‐anethole (94.37%), methyl chevicol (1.82%) and cis‐anethole (1.59%). 15 Components were identified from its acetone extract accounting for 80.27% of the total amount. trans‐Anethole (51.81%) was found as a major component along with linoleic acid (11.6%), 1‐(4‐methoxyphenyl)‐prop‐2‐one (6.71%), foeniculin (5.29%) and palmitic acid (1.47%). Using an inverted petriplate method, the volatile oil completely inhibited the growth of Fusarium moniliforme at 6 µl dose. In case of extract, 50% mycelial zone inhibition was obtained for Penicillium citrinum and Penicillium viridicatum. Moreover, using food poison technique, the volatile oil was found to be effective for controlling the growth of F. moniliforme and Aspergillus niger whereas the extract has been found to be highly effective for Aspergillus flavus. In antibacterial investigations, using agar well diffusion method, the extract has shown better activity for Staphylococcus aureus and Bacillus cereus in comparison with volatile oil and commercial bactericide, ie Ampicillin. However, volatile oil has shown better activity for Salmonella aeruginosa and Bacillus subtilis. Moreover, the extract has shown excellent activity for the inhibition of primary and secondary oxidation products in rapeseed oil which were evaluated using peroxide, thiobarbituric acid, p‐anisidine and carbonyl values. The activity of extract was further confirmed using other antioxidant properties such as ferric thiocyanate method in linoleic acid system, reducing power and scavenging effect (%) on 1,1‐diphenyl‐2‐picrylhydrazyl radical (DPPH) radical. Hence, the extract could be considered as natural antioxidant which may be used for chemoprevention of diseases occurring due to oxidative deterioration. Copyright © 2005 Society of Chemical Industry  相似文献   
13.
In this paper, a novel subspace projection approach is proposed for analysis of speech signal under stressed condition. The subspace projection method is based on the assumption of orthogonality between speech subspace and stress subspace. Speech and stress subspaces contain speech and stress information, respectively. The projection of stressed speech vectors onto the speech subspace will separate speech-specific information. In this work, the speech subspace consists of neutral speech vectors. Speech and stress recognition techniques are used to verify the orthogonal relation between speech and stress subspaces. The evaluation database consists of 119 word vocabulary under neutral, angry, sad and Lombard conditions. Hidden Markov models for speech and stress recognition are used with mel-frequency cepstral coefficient features for evaluation of estimated speech and stress information.  相似文献   
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Prakash S  Singh S  Rana S 《Applied optics》2005,44(28):5905-5909
A technique for a tilt-angle measurement of reflecting objects based on the Lau interferometry coupled with the moire readout has been proposed. A white-light incoherent source illuminates a set of two gratings, resulting in the generation of the Fresnel image due to the Lau effect. The Fresnel image is projected onto a reflecting object. The image reflected from the object is superimposed onto an identical grating, which results in the formation of a moiré fringe pattern. The inclination angle of moiré fringes is a function of tilt angle of the object. Theory and experimental arrangement of the proposed technique is presented and results of the investigation are reported.  相似文献   
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The aim of this investigation was to determine the bioactive compounds and the antioxidant potentials of Snake fruit and Mangosteen and their influence on plasma lipid levels and antioxidant activity in rats fed cholesterol-containing diets. It was found that total polyphenols and antioxidant potentials of Snake fruit were significantly higher than those of Mangosteen (P < 0.05). A cholesterol-containing diet supplemented with the studied exotic fruits showed a positive affect on rat’s plasma lipid levels and on the antioxidant activity during 30 days of feeding. In rat’s plasma of the Chol/Snake diet group, the fibrinogen fraction showed a decrease in the amounts and compositions of electrophoretic protein bands in the range of 110 and 14 kDa. However, all the positive results of this experiment on animals could not be automatically applied to humans.  相似文献   
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In pot and field experiments cereals were grown with greatly differing rates of N, P and K applications. For maize and sorghum, soil moisture levels were also varied. N applications, P- and K-deficiency, and moisture stress generally increased the total N content of grain, from 1.06 to 2.68, 1.01 to 2.42 and 0.81 to 2.33% (as % of DM) for maize, sorghum and rice, respectively. P, K and moisture stress affected the amino acid composition only indirectly through their effects on N concentration. In all three cereals increasing N concentrations were associated with decreases in crude protein of lysine, methionine, cystine, threonine, tryptophan and, generally, with increases of isoleucine, leucine, phenylalanine and glutamate. Lysine as a percentage of dry matter increased up to the highest N concentration in all three cereals. Linear regressions with significant correlation coefficients were found between concentrations of most (g 16 g?1 N) or all (mg 100 g?1 DM) amino acids and N content of grain. Based on all experimental data equations for lysine were: g 16 g?1 N=4.44–0.89 × %N; 4.23–0.86 × % N; 4.39–0.42 × % N for maize, sorghum and rice, respectively. Correction of P- and K-deficiency decreased N content of grain and resulted in higher lysine content and better nutritional value of grain protein, whereas correction of N-deficiency had the opposite effect. The amino acid composition of rice was much more balanced than that of maize and sorghum with a leucine/isoleucine ratio of 2 compared to that of 3 in maize and sorghum. In rat feeding experiments true digestibility of maize and sorghum protein was high (about 95%) but increased only slightly with increasing N in grain, whereas the biological value decreased considerably, from 63 to 55 and from 70 to 58, respectively. The chemical score underestimated the nutritional value of both cereal proteins.  相似文献   
20.
A series of cobalt substituted lithium zinc ferrites having the compositional formula Li0.4–0.5xZn0.2CoxFe2.4–0.5xO4, where 0.00 ≤ x ≤ 0.1 in steps of 0.02, was prepared by the citrate precursor method. Structural studies on the prepared samples were carried out by using XRD and SEM measurements. Spinel phase structure of the samples was confirmed by XRD. From the XRD data the lattice parameter and the theoretical density were calculated. The experimental density was also determined using the Archimedes principle. Lattice parameter was observed to increase with increasing Co2+ ion concentration. The densification in both the cases, theoretical and experimental, shows an increase with composition. SEM studies carried out show that average grain diameter are in the range of 300 nm–650 nm and a fall is observed with increasing Co2+ ion content. The investigation on initial permeability as a function of composition and frequency were also undertaken. It is seen that there is decrease in the value of initial permeability with addition of Co content. The initial permeability and permeability loss show dispersion with frequency. Possible mechanisms contributing to the above processes are discussed.  相似文献   
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