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1.
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   
2.
In industrial fluid cokers the feedstock, consisting of heavy bituminous hydrocarbons, is atomized with steam and injected into a hot fluidized bed of coke. Good and uniform contact of the liquid droplets with the solid particles is required to provide heat for the cracking reactions while minimizing mass transfer effects. Experiments in a pilot plant coker have suggested that the initial particle/liquid mixing, in the spray jet, is rather poor. Experiments in a X-ray scanner showed that liquid droplets and entrained particles accumulate just below the tip of the jet plume to form agglomerates.An experimental technique was used to quantitatively determine the quality of mixing with a variety of nozzle configurations including several novel designs. By improving spray stability, redistributing liquid droplets to the solids-rich region of the jet and increasing the surface area of the gas-liquid jet-fluidized bed interface, liquid/solid contact is improved.  相似文献   
3.
Degumming of hemp fiber by high temperature alkali cooking was investigated, and the effect of temperature and dosage of alkali on the constituents, structure, and thermal degradation of hemp fiber was also discussed in this work. The morphology, structure, and thermal degradation of hemp fiber after high temperature cooking were investigated through SEM, FTIR, WAXD, and TG analysis. The results indicated that the high temperature cooking process was effective for removing hemicelluloses and lignin and could also improve the thermal stability of cellulose. Crystallinity index of the treated hemp fiber was increased, which was related to the cooking temperature and NaOH dosage. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
4.
Systems processed by thermoplastic extrusion can be regarded as heterophase polymer melts of incompatible water-plasticized biopolymers. In the process of thermoplastic extrusion, proteins and polysaccharides are melted at high pressure and temperature below the temperature region of their thermal decomposition. Dispersed particles of these systems can be deformed in flow. The mixed-melt anisotropic structure, formed in flow, is fixed by rapid conversion of the melt jet that lets the extruder die from a viscous state to a rubber-like state and then to a glassy state caused by cooling and drying. Incompatibility of proteins and polysaccharides in their water-plasticized melt mixtures impacts on structure formation and texturization during thermoplastic extrusion. Presented at the 20th ISF World Congress and 83rd AOCS Annual Meeting and Expo, May 10–14, 1992, Toronto, Ontario, Canada.  相似文献   
5.
介绍了国内首套双容器KAMYR连蒸系统的特点,总结了该系统生产运行控制的关键环节,对其中筛选部分技术改造的必要性进行了阐述,并分析、总结了技改的成功经验及其显著效果。  相似文献   
6.
Amylomaize V, amylomaize VII, wheat and rice starches were extrusion cooked in a single-screw extruder at 140°C barrel temperature and 140 rpm screw speed. Extrudates were ground and re-extruded through a 3 mm cylindrical die nozzle using screws with no mixing (NM), 1 mixing (1M) or two mixing (2M) elements. Overall expansions were the highest and bulk densities were lowest with 1M. Radial expansions for amylomaize V, amylomaize VII, and wheat starches were the highest with 1M and lowest with 2M. Amylopectin contents of starches decreased with corresponding increases of gel permeation chromatograph peak II fractions when number of mixing elements was increased. λmax values of peak I and peak II decreased upon re-extrusion of starches with increasing number of mixing elements.  相似文献   
7.
The concentrations of individual and total glucosinolates were measured in four types of Portuguese cabbage and in one hybrid white cabbage before and after cooking. Typical Portuguese culinary procedures include boiling the cabbage for 10 min but for particular kale types the leaves are first shredded then boiled for 5 min (Caldo verde). Analysis of the fresh cabbage, cooked leaves and cooking water showed that the glucosinolate content of the cabbages is reduced by more than 50%. Almost all of this loss is accounted for as intact glucosinolates in the cooking water, normally used for soups in Portugal.  相似文献   
8.
周一鹿  陈忠敏 《丝绸》1994,(9):22-24
本文针支目前我国煮茧实务中存在的主要问题,参考日本对煮熟度与绪丝量、丝量的关系,影响清洁成绩的大环类,裂丝的发生数与茧吐水量、膨化率的关系的研究结果,提出了解决问题的有效方法。  相似文献   
9.
A study was made of the effect that final internal processing temperature (63, 70 and 78°C) and chilling storage (2°C) exerted on the characteristics (cooking loss, purge loss, colour, Instron texture profile analysis) of high-fat (242 g kg−1) and low-fat (100 g kg−1) bologna sausage. High-fat sausages were harder and chewier than low-fat sausages. Lower fat contents were accompanied by a significant reduction in the cooking loss and purge loss. Binding properties were not affected ( P> 0·05) by final internal cooking temperature. In general, Hunter colour parameter a values were higher in low-fat samples subjected to a high final internal cooking temperature than in those cooked up to only 63°C. High internal temperatures produced harder meat emulsions, an effect which was more pronounced in high-fat than in low-fat sausages. Cohesiveness and springiness of sausages was not affected ( P> 0·05) by heat treatment. There were no major variations in textural parameters as a result of chilled storage.  相似文献   
10.
实验研究了不同超高压条件对湿粉条中腐败霉菌黑曲霉(Aspergillus 305.01和Aspergillus 305.02)杀菌效果以及对粉条蒸煮特性的影响。实验结果表明随着处理压力升高和时间延长,超高压对黑曲霉的杀菌效果增强。经400 MPa/10 min的超高压处理后,粉条的Aspergillus 305.01与Aspergillus 305.02均下降了6.01个对数值;与未处理菌悬液相比,Aspergillus 305.01和Aspergillus 305.02的核酸吸光值分别从0.03和0.04增加至0.56和0.48、蛋白质吸光值分别从0.04和0.08增加至0.70和0.44、电导率分别从0.04 mS/cm和0.06 mS/cm增加至0.12 mS/cm和0.20 mS/cm。在400 MPa处理下,提高超高压处理时间,电导率、核酸损失和蛋白质损失增多,表明超高压是通过改变细胞膜的部分功能,引起胞内核酸、蛋白质和电解质等物质流出,从而导致细胞死亡。此外,随着处理时间增加,粉条的煮沸损失、膨润度增大,而断条率变化不显著。综合超高压对湿粉条的杀菌效果和蒸煮特性的影响,400 MPa处理10 min是湿粉条杀菌的较优条件,为超高压改善湿粉条的杀菌效果和品质提供了理论依据。  相似文献   
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