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1.
Angiotensin I‐converting enzyme inhibitory and Ca‐binding activities of peptides prepared from tuna cooking juice and spleen proteases 下载免费PDF全文
Jirawadee Kasiwut Wirote Youravong Pittaya Adulyatham Nualpun Sirinupong 《International Journal of Food Science & Technology》2015,50(2):389-395
Tuna cooking juice is a by‐product from the tuna canning industry. In this study, tuna cooking juice was hydrolysed by proteases extracted from the spleen. Tuna cooking juice showed the highest ACE inhibitory and Ca‐binding activities after hydrolysis for 270 and 180 min, respectively. The hydrolysate was further fractionated by ultrafiltration. The permeate exhibited highest ACE inhibitory and Ca‐binding activities when passed through 1 and 5 kDa cut‐off membranes, respectively. Gel filtration chromatography was used to determine the MW of bioactive peptides that exhibited highest ACE inhibitory and Ca‐binding activities. Those peptides that exhibited highest ACE inhibitory and Ca‐binding activities were the MW range of 238–829 Da and 1355–1880 Da, respectively. These results suggest that the tuna cooking juice and the spleen protease extract are a potential source of bioactive peptides that can be utilised as bioactive ingredients in functional food and nutraceuticals. 相似文献
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橡胶卷材挤出连续硫化生产线的结构特色与工作原理 总被引:1,自引:0,他引:1
介绍了橡胶防水防腐卷材挤出连续硫化生产线的结构、特点和工作原理;指出在目前国内同类设备中,该生产设备具有先进性,并可替代引进设备。 相似文献
4.
The thermal and mechanical properties and the morphologies of blends of poly(propylene) (PP) and an ethylene–(vinyl alcohol) copolymer (EVOH) and of blends of PP/EVOH/ethylene–(methacrylic acid)–Zn2+ ionomer were studied to establish the influence of the ionomer addition on the compatibilization of PP/EVOH blends and on their properties. The oxygen transmission rate (O2TR) values of the blends were measured as well. PP and EVOH are initially incompatible as was determined by tensile tests and scanning electronic microscopy. Addition of the ionomer Zn2+ led to good compatibility and mechanical behaviour was improved in all blends. The mechanical properties on extruded films were studied for 90/10 and 80/20 w/w PP/EVOH blends compatibilized with 10 % of ionomer Zn2+. These experiments have shown that the tensile properties are better than in the injection‐moulded samples. The stretching during the extrusion improved the compatibility of the blends, diminishing the size of EVOH domains and enhancing their distribution in the PP matrix. As was to be expected, the EVOH improved the oxygen permeation of the films, even in compatibilized blends. Copyright © 2004 Society of Chemical Industry 相似文献
5.
Al-Li alloys being developed as lighter, substitutes for conventional high strength Al alloys are to be processed by routine
methods. During extrusion of a 8090 Al-Li alloy, the extrusion die container failed causing some alarm. This failed die container
was analysed to examine if the failure was caused by interaction of Li diffusing out of Al-Li alloy with the carbides of die
steel. The evidence, although not conclusive, is sufficient to exercise caution during such processing. 相似文献
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7.
Sang C. Park 《The Visual computer》2003,19(1):38-49
A sweeping operation called polygonal extrusion is defined to improve the modeling power of CSG-based modeling. It is assumed that a 2D cross-sectional polygon (sweeping
polygon) moves in space while its containing plane is kept orthogonal to the tangent direction of the trajectory curve, a planar
polygonal chain having no self-intersections. The objective of the paper is to compute the boundary of the swept volume of
the sweeping polygon as a set of polygons (or triangles). The most significant challenge to accomplishing this objective is
the problem of trimming the swept volume. To solve the trimming problem, 2D-curve offsetting methods are employed. Two algorithms
are presented for polygonal extrusion that are based on different offsetting methods, the Voronoi diagram and PWID offset.
The proposed algorithms have been implemented and tested with various examples.
Published online: 28 January 2003 相似文献
8.
双螺杆反应挤出模型的研究 总被引:5,自引:0,他引:5
详细研究了双螺杆中反应挤出聚合物的动力学模型、流动模型和传热模型。通过实验得到了双螺杆反应器中聚合物的停留时间分布及平均停留时间。 相似文献
9.
JUJUN JULIANTY† PANFILO BELO‡ ELVEDA SMITH‡ LUCY McPROUD‡ 《International Journal of Food Science & Technology》1994,29(3):315-320
Four levels of egg white powder (EWP), 0, 1.5, 3.0 and 4.5%, were added to fisfc cracker formulation consisting of tapioca starch, fish paste, and water. the mixture was extruded through a single screw extruder, and the extrudate was cut, dried, heated in a microwave, and the degrees of expansion, bulk density, colour and protein content were measured.
The addition of 1.5 and 3.0% EWP had no significant effect ( P < 0.01) on diametral and longitudinal expansion, however, 4.5% EWP significantly ( P < 0.01) reduced them. Bulk density and protein content of the final product increased as the percentage of EWP increased in the formulation. the total colour difference measurement showed a significant increase ( P < 0.01) in brown colouration at 4.5% EWP. 相似文献
The addition of 1.5 and 3.0% EWP had no significant effect ( P < 0.01) on diametral and longitudinal expansion, however, 4.5% EWP significantly ( P < 0.01) reduced them. Bulk density and protein content of the final product increased as the percentage of EWP increased in the formulation. the total colour difference measurement showed a significant increase ( P < 0.01) in brown colouration at 4.5% EWP. 相似文献
10.
B.M. Naveena A.R. Sen M. Muthukumar S. Vaithiyanathan Y. Babji 《Journal of food science》2006,71(9):S603-S608
ABSTRACT: The aim of this study was to determine the effect of adding 3.3% sodium lactate (SL), 0.25% calcium lactate (CL), and 1.65% SL along with 0.125% CL (SL+CL) on the physicochemical properties, cooking characteristics, and microbiological quality of microwave-cooked chicken patties compared to control (no added lactates). The addition of lactates did not affect the proximate composition of cooked chicken patties. The pH of CL- or SL+CL-containing patties was significantly ( P < 0.05) reduced compared to control or SL patties. The SL-containing patties had lower ( P < 0.05) a w values compared to control or CL patties. The CL- or SL+CL-containing patties had lower denatured myoglobin and higher ( P < 0.05) cooking yield, surface redness (CIE a *), and chroma values. However, addition of CL alone resulted in higher total expressible fluid, indicating lower water-holding capacity. The CL-containing patties exhibited lower Warner–Bratzler shear force values and higher ( P < 0.05) penetrometer reading compared to the SL-containing patties, indicating soft texture. Thiobarbituric acid (TBA) values were significantly ( P < 0.05) reduced in all lactate-containing patties compared to control up to the 7th day of refrigerated storage under aerobic conditions. No difference ( P > 0.05) was observed in aerobic plate counts between control and lactate-added patties during 28-d storage. 相似文献