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91.
Graft copolymers of potato starch with acrylamide, acrylamide, and acrylic acid or N‐vinylformamide in the presence of 1–16 wt % montmorillonite were manufactured via reactive extrusion. XRD and TEM measurements exhibited intercalated structure of clay dispersion (d001 distance up to 2.3 nm). The influence of graft polymer(s) system and montmorillonite content on thermal properties, water sorption as well as polyvalent metal cation (Cd2+ and Fe3+) sorption of obtained starch graft copolymers has been determined. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
92.
The total lipids (8.6%) extracted from whole lupin seeds (Lupinus angustifolius L. var. “Uniwhite”) were found to be comprised of triglycerides (71.1%), phospho-lipids (14.9%), free sterols (5.2%), glycolipids (3.5%), sterol and wax esters (0.5%), free alcohols (0.4%), hydrocarbons (0.4%) and unidentified waxy material (4.0%). The main fatty acids in the total lipid extract were linoleic (48.3%), oleic (31.2%), palmitic (7.6%) and linolenic (5.4%). Erucic acid was not present, nor were cyclopropenoid acids. Seed coatings constituted 23.9% of the weight of the whole seeds and contained 1.5% lipids, the main classes of which were triglycerides (38.4%), free sterols (28.0%), phospholipids (9.7%), glycolipids (9.1%) and free alcohols (3.7%). The seed coatings and kernels contained the same fatty acid constituents, but the proportions of oleic, linoleic and linolenic acids were markedly different. β-Carotene was present, although at low concentration. When evaluated on its lipid composition, “Uniwhite” lupin seed appears suitable as a supplement for pig, poultry and stock feeding.  相似文献   
93.
94.
Laboratory and full-scale experiments were conducted to investigate the development and effect of heterogeneity caused by filter media nonuniformity, biofilm, particles, precipitates, and gas bubbles in rapid sand filters used for drinking-water treatment. Salt tracer experiments were conducted in laboratory columns and in a waterworks, where a new tracer method for rapid sand filters was developed. Pore-water velocities and dispersivities were estimated by fitting an analytical solution to the measured breakthrough curves. Results of the column experiments showed an increase in average longitudinal dispersivity of more than 33% in the 116?h after the start of filtration with a constant pore-water velocity and a zero-order nitrification rate of 9??mg?N/L/h. The full-scale experiments showed that the rapid sand filter was heterogeneous with pore-water velocities ranging from 2.2 to 3.3??m/h for the same inlet flow. A first-order nitrification reaction with spatially variable pore-water velocity could be interpreted as a zero-order reaction with a constant pore-water velocity. A model demonstrated that filter heterogeneity could result in higher filter outlet ammonium concentrations.  相似文献   
95.
Protection of Metals and Physical Chemistry of Surfaces - The paper presents mechanical properties of the porous Ti scaffold made with saccharose as a space holder. The Ti scaffolds had the...  相似文献   
96.
The present work determined iron content in fourteen species of vegetable prepared for consumption. The experimental material consisted of raw and boiled raw vegetables and two types of frozen product: one traditionally produced (blanching before freezing); the other obtained using the modified method (boiling before freezing), having the characteristics of a ready‐to‐eat convenience product. Nutrient density (ND) and recommended dietary intake (RDI) were established on the basis of iron content. The highest iron content was found in pea seeds (2.03 mg per 100 g fresh weight) and the lowest in root vegetables (0.38–0.60 mg). Iron retention was similar in all pea, broad bean, New Zealand spinach, kale, white cauliflower, celery and red beet products. In the remaining products, the significantly lowest retention was found in the traditionally frozen product (Sample C) and the highest in the ‘convenience’ frozen product (Sample D). The above‐mentioned order also applied to ND and RDI values. Only in the ND of parsnip calculated for women did any value fall below 100%.  相似文献   
97.
The aim of this study was to determine the quality indices and assess the influence of diets supplemented with mussels from contaminated (MCont) and non-contaminated areas (MNCont) on some indices of protein and lipid metabolism in rats fed with cholesterol. A wide range of in vitro tests demonstrated that mussels from contaminated area have a higher content of proteins, lipids and higher antioxidant capability. In the in vivo experiment, 28 male Wistar rats were divided into 4 diet groups each of 7 and named Control, Cholesterol (Chol), Chol/MCont and Chol/MNCont. During 30 days of the experiment rats of all four groups were fed basal diet (BD), supplemented with 1% of Chol, 1% of Chol and 5.6% of mussel’s dry matter (DM) from contaminated and 1% Chol and 5.6% of mussel DM from non-contaminated areas for Chol/MCont and Chol/MNCont groups, respectively. At the end of the experiment, a high digestibility coefficient of DM and crude protein in the Chol/MCont and Chol/MNCont groups of rats was found: 93.56 and 93.87% and 91.64 and 91.36%, respectively, and the differences were not significant (P > 0.05). However, the protein efficiency ratio was significantly higher in the Chol/MCont and Chol/MNCont than in the Control and Chol diet groups. Also the level of nitrogen retention as shown by feces and urine examination was higher in the Chol/MCont and Chol/MNCont groups. Diet, supplemented with mussel dry matter from both contaminated and non-contaminated areas significantly hindered the rise in plasma lipids and also hindered the decrease in plasma antioxidant activity. Minor changes were fixed in the protein profile of rat’s plasma after both mussels’ diet. In conclusion, supplementation of diets, containing cholesterol with mussels’ DM from both contaminated and non-contaminated areas improves animals’ protein metabolism and positively affects plasma lipid profile and plasma antioxidant activity. Antioxidant tests can be used as an additional index for the quality of mussels.  相似文献   
98.
The aim of the investigation was to evaluate the level of amino acids and the quality of protein in fresh and cooked leaves of kale and in two types of frozen product prepared for consumption after 12-months storage at −20 °C. Kale blanched before freezing (the traditional method) was cooked after refrigerated storage, while that cooked before freezing (the modified method) was defrosted and heated in a microwave oven. Both fresh and processed leaves of kale were a good source of amino acids. In all the samples, glutamic acid, proline and aspartic acid were the dominant, while lysine and leucine were the limiting amino acids. Cooked leaves contained 78% of the total amino acid content found in fresh leaves, while the traditional and modified frozen products contained 76% and 78%, respectively. The proportion of essential amino acids in total amino acids was 44% and 43%, respectively for fresh and cooked leaves and 46% for the frozen products. The lowest EAA index was found for the traditional frozen product (99); it was higher for the remaining samples, which were broadly similar to each other (105–106).  相似文献   
99.
Hansen  R. P.  Czochanska  Zofia 《Lipids》1974,9(10):825-827
Lipids - Phytanic, pristanic, and 4,8,12-trimethyltridecanoic acids were found to comprise from 2.7% (winter) to 13.3% (spring) of the fatty acids of the neutral lipids of earthworms collected in...  相似文献   
100.
Natural aggregates are characterized by considerable variability in their technical properties/sand, silt and clay fractions. The statistical estimation of the homogeneity of domestic natural aggregates was carried out at the Institute of Technology and Organization of Building Production in Warsaw Technical University. Total number of results amounted two thousand. A calculation has been made by EMC “Odra 204” for a program in algoritmic language Algol. Equations derived permit the forecast with 95% probability of the compressive strength of Portland—cement concrete on the basis of the variability of features of the aggregates.  相似文献   
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