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271.
Lecithin:cholesterol acyltransferase (LCAT) deficiency is a genetic disorder associated with low levels of serum HDL cholesterol. The proband of the Finnish LCAT-deficient family had corneal opacities, proteinuria, anemia with stomatocytosis, low serum HDL cholesterol (0.27 mmol/L), and low LCAT activity. Sequence analysis of his LCAT gene revealed compound heterozygosity for two different mutations: a C insertion in exon 1 between nucleotides 932 and 937 and a C-to-T point mutation in exon 6 at position 4976. The C insertion in exon 1 is predicted to result in premature termination and a truncated polypeptide containing only 16 amino acids. The C-to-T point mutation in exon 6 substitutes cysteine for arginine at residue 399. The functional significance of the Arg399-->Cys mutation was examined by expressing the mutated and wild-type LCAT cDNAs in COS cells. COS cells transfected with mutated and wild-type cDNAs showed comparable levels of mature LCAT mRNA. However, LCAT activity in the cell media of COS cells transfected with the mutant LCAT cDNA was significantly lower than that of COS cells transfected with the wild-type cDNA (1.4% versus 12.0% cholesterol esterified, respectively). A polymerase chain reaction-based duplex assay, in which both mutations can be detected simultaneously, was used for preliminary screening of Finnish subjects with serum HDL levels below 0.9 mmol/L; two additional individuals heterozygous for the Arg399-->Cys mutation were identified.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
272.
Predicting time-sharing in mobile interaction   总被引:1,自引:0,他引:1  
The era of modern personal and ubiquitous computers is beset with the problem of fragmentation of the user’s time between multiple tasks. Several adaptations have been envisioned that would support the performance of the user in the dynamically changing contexts in which interactions with mobile devices take place. This paper assesses the feasibility of sensor-based prediction of time-sharing, operationalized in terms of the number of glances, the duration of the longest glance, and the total and average durations of the glances to the interaction task. The data used for constructing and validating the predictive models was acquired from a field study (N = 28), in which subjects performing mobile browsing tasks were observed for approximately 1 h in a variety of environments and situations. The predictive accuracy achieved in binary classification tasks was about 70% (about 20% above default), and the most informative sensors were related to the environment and interactions with the mobile device. Implications to the feasibility of different kinds of adaptations are discussed.  相似文献   
273.
Anthocyanins, the natural red and purple colorants of berries, fruits, vegetables, and tubers, improve carbohydrate metabolism and decrease the risk factors of metabolic disorders, but their industrial use is limited by their chemical instability. Acylation of the glycosyl moieties of anthocyanins, however, changes the chemical properties of anthocyanins and provides enhanced stability. Thus, acylated anthocyanins are more usable as natural colorants and bioactive components of innovative functional foods. Acylated anthocyanins are common in pigmented vegetables and tubers, the consumption of which has the potential to increase the intake of health-promoting anthocyanins as part of the daily diet. For the first time, this review presents the current findings on bioavailability, absorption, metabolism, and health effects of acylated anthocyanins with comparison to more extensively investigated nonacylated anthocyanins. The structural differences between nonacylated and acylated anthocyanins lead to enhanced color stability, altered absorption, bioavailability, in vivo stability, and colonic degradation. The impact of phenolic metabolites and their potential health effects regardless of the low bioavailability of the parent anthocyanins as such is discussed. Here, purple-fleshed potatoes are presented as a globally available, eco-friendly model food rich in acylated anthocyanins, which further highlights the industrial possibilities and nutritional relevance of acylated anthocyanins. This work supports the academic community and industry in food research and development by reviewing the current literature and highlighting gaps of knowledge.  相似文献   
274.
The equilibrium sampling in silicone is increasingly applied to measure freely dissolved concentrations and chemical activities within bioaccumulation research of hydrophobic organic chemicals. Two equilibrium methods were applied to PCB-contaminated soil and sediment, and directly calibrated with respect to equilibrium partitioning concentrations in lipids (C(lipid,partitioning)): (i) Solid phase microextraction in the headspace above the sample (HS-SPME) required optimization for its application to PCBs, and it was calibrated above external partitioning standards in olive oil. (ii) Equilibrium sampling with internally coated glass jars with varying thicknesses of silicone (PDMS) resulted in proportionality between coating and analyte mass, which confirmed several validity criteria. C(lipid,partitioning) was here determined as product of PDMS concentration and PDMS to lipid partition ratio. The results of the two methods were in good agreement and thus validated each other. Finally, the coated glass jar method was applied to field sediment containing invertebrates, which lead to C(lipid,partitioning) that were about two times higher than measured lipid-normalized concentrations in the organisms. Temperature differences and animal lipid structure were discussed as possible reasons for this discrepancy. Both methods combine high analytical performance, reduced equilibration times and new calibration possibilities, which makes them suited for bioaccumulation research and environmental monitoring.  相似文献   
275.
Printed, organic diodes with a thin organic interfacial layer forming a Schottky barrier were fabricated and characterized. Experiments indicated that the thickness of the barrier layer is <10 nm. The interfacial layer reduces the reverse current of the diode by 2 orders of magnitude without significantly affecting the forward characteristics above 1 V. As a result, printed organic diodes with a rectification ratio of 5 orders of magnitude were fabricated. The diodes enable applications where low reverse currents are needed.  相似文献   
276.
Model-order reduction (MOR) is a typical approach to speed up the post-layout verification simulation step in circuit design. This paper studies the benefits of using circuit partitioning in a complete MOR flow. First, an efficient reduction algorithm package comprising of partitioning, reduction, and realization parts is presented. The reduction flow is then discussed using theoretical analysis and simulations from an array of 65-nm technology node interconnect circuits. It is shown that the reduction efficiency and computational costs quickly worsen with increased circuit size when using a direct projection-based MOR approach. In contrast, by using partitioning, the MOR can retain the scalability of the reduction problem, being computationally lighter and more efficient even with larger circuits. In addition, using partitioning may improve the robustness of the MOR flow in cases with circuits with many ports or sensitive verification simulations.  相似文献   
277.
The main objective of this study was to determine the level of surface contamination in fish processing factories and the presence of Listeria in the factory environment and products. Another objective was evaluation of the different hygiene-monitoring methods. Total aerobic heterotrophic and enterobacteria, yeast and mold samples were collected and ATP levels measured in 28 factories. The number of well or adequately washed and disinfected factories was small (2 of 28), in terms of total aerobic heterotrophic bacterial counts on the surfaces. Most surfaces contaminated with bacteria were heavily contaminated. Results of the ATP and the total bacteria contact agar slide methods were poorly correlated (r = 0.21) although 68% of the samples were categorized as good to moderate or unacceptable with both methods. The Listeria-positive surface samples usually contained increased numbers of total bacteria (70.9%). The contamination of products and raw fish together with Listeria spp. was 45% and with Listeria monocytogenes 12%. Cold smoked fish was the most contaminated, with 75% Listeria spp. and cold salted fish with 20% L. monocytogenes. Listeria innocua was found in the samples more than twice as often as L. monocytogenes.  相似文献   
278.
Rye bran is a high-fibre ingredient also containing starch and protein. The aim of this work was to investigate the effects of extrusion processing and bran particle size on the structural and mechanical properties of extruded rye bran. Native rye bran particle size of 750–1,250 μm was milled to produce feed material with three different average particle sizes (coarse, 440 μm; medium, 143 μm; fine, 28 μm). A co-rotating twin screw extruder was used for extrusion with various processing parameters. Extrusion processing did not have a significant (P?<?0.05) effect on soluble dietary fibre (SDF) content but the amount of insoluble dietary fibre (IDF) increased by 7.1–9.5 % in medium- and 11.3–12.3 % in fine-particle-sized rye bran extrudates as compared to the raw material prior to extrusion. Decreasing the particle size of rye bran to 28 μm resulted in lower amounts of IDF and total dietary fibre, but a higher amount of SDF after extrusion compared to coarse-particle-sized rye bran. Decreasing the particle size of rye bran to 28 μm gave more expanded (179–223 %), less hard (145–336 N), more crispy (2.7–7.2?×?10?4) and porous (79.2–83.9 %) extrudates compared to the coarse-particle-sized rye bran extrudates, which were less expanded (151–176 %), harder (210–433 N), less crispy (0.5–2.8?×?10?4) and less porous (64.4–65.1 %). Reduction of the particle size of rye bran significantly (P?<?0.05) increased the crispiness compared to the extrudates made of coarse-particle-sized rye bran. The results demonstrated that the structural and mechanical properties of rye bran extrudates can be improved without starch addition by reducing the particle size of bran.  相似文献   
279.
ABSTRACT: The capability of an electronic nose, MGD-1, in the detection of aroma differences among 5 samples of strawberry ice cream of varying fat content (0,9, or 18% dairy or vegetable fat) was compared with the human nose. R-indices were determined to detect sensory differences. In addition, the headspace compositions of samples were determined with static headspace gas chromatography. The effect of the amount of fat on the aroma release could be detected with all three methods. The headspace of the nonfat sample was very different from the other samples, but samples containing 9 or 18% of fat were also differentiated. The type of fat did not significantly affect the aroma release. The MGD- 1's capability for detecting the aroma differences was fairly comparable with the sensory and the static headspace gas chromatographic method.  相似文献   
280.
The in vitro fermentabilities of rye, wheat and oat brans and of a commercial fibre preparation, inulin, were compared. The brans were first digested enzymatically to remove starch and protein. The digested brans and inulin were then fermented with human faecal inoculum. The progress of fermentation was studied by following the consumption of carbohydrates and the production of short‐chain fatty acids and gases. Inulin, a short fructose polymer, was consumed significantly faster than the more complex carbohydrates of cereal brans. Carbohydrates of oat bran (rich in β‐glucan) were consumed at a higher rate than those of rye and wheat brans (rich in arabinoxylan). In all brans, glucose was consumed faster than the other main sugars, arabinose and xylose, and arabinose was degraded only slightly. The total production of short‐chain fatty acids was slightly higher with oat bran than with rye and wheat brans and inulin. In the fermentation of inulin, relatively more butyric acid and less propionic acid were produced than in the fermentation of brans. The decrease in pH was also greater in the case of inulin. Wheat bran led to a slightly slower gas formation than rye and oat brans. Formation of gases was fastest and greatest in the case of inulin. In conclusion, rye, wheat and oat brans were fermented in a rather similar way. Fermentation of the brans was different from that of inulin. Cereal brans might serve as a more balanced source of dietary fibre supplement than gas‐producing, readily fermentable polysaccharides such as inulin. © 2000 Society of Chemical Industry  相似文献   
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