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11.
Abstract The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plantsobtained whose protein content was higher than 18.5%, the highest one was 21.44%. There were 3plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We cansee that the whole DNA of soybean transformed into wheat via ion beam implantation can inducethe increase in wheat protein content dramatically. The result also shows that the transformationefficiency of different gene types of wheat receptor varies greatly that the implanting time has acertain effect on the efficiency of transformation.  相似文献   
12.
关于影响面条食用品质相关因素的探讨   总被引:3,自引:0,他引:3  
从小麦生产概况、面条发展历史和工艺、国内外对面条食用品质的研究3个方面,分析了我国面条工业发展缓慢的原因,提出了小麦育种-面粉工业-制面工业,3个环节紧密配合,协调发展,才能形成良性循环的新思路。  相似文献   
13.
Crosslinking modification can effectively improve the water resistance of soy protein isolate (SPI) adhesive, but it often depends on petroleum-based reagents, violating the concept of green environmental protection. Here, inspired by the breaking and recombination of the disulfide bond in the perm process, a high-performance wood adhesive is prepared by incorporation of SPI (modified by sodium sulfite to cleave the disulfide bonds of protein chains) and feather keratin (FK, extracted from waste chicken feathers by breaking the disulfide bond) without using any other crosslinkers. The crosslinking reaction occurs by disulfide bonds derived from the sulfhydryl group of FK and SPI. Thus the wet shear strength of the SPI/FK-20 adhesive is improved from 0.57 to 1.18 MPa, an increment of 107%. This study provides a green strategy to prepare high-performance protein-based adhesive from the waste products-chicken feathers, which will contribute to the development of the environmentally friendly wood adhesive industry.  相似文献   
14.
The objective of this study was the production of rice husk flour (RHF) and wood flour (WF) filled polybutylene succinate (PBS) biocomposites as alternatives to cellulosic material filled conventional plastic (polyolefins) composites. PBS is one of the biodegradable polymers, made from the condensation reaction of 1,4‐butanediol and succinic acid that can be naturally degraded in the natural environment. We compared the mechanical properties between conventional plastics and agro‐flour–filled PBS biocomposites. We evaluated the biodegradability and mechanical properties of agro‐flour–filled PBS biocomposites according to the content and filler particle size of agro‐flour. As the agro‐flour loading was increased, the tensile and impact strength of the biocomposites decreased. As the filler particle size decreased, the tensile strength of the biocomposites increased but the impact strength decreased. The addition of agro‐flour to PBS produced a more rapid decrease in the tensile strength, notched Izod impact strength, and percentage weight loss of the biocomposites during the natural soil burial test. These results support the application of biocomposites as environmentally friendly materials. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1513–1521, 2005  相似文献   
15.
羟丙基糯米粉糊的特性及应用初探   总被引:1,自引:0,他引:1  
研究了羟丙基糯米粉糊的性质,以及流变特性和温度影响流变特性的规律,并对其在蚝油食品中作为增稠稳定剂的应用做了初步研究。结果表明,糯米粉经羟丙基化后,凝沉性更弱,受热易于成糊和分散,糊的粘度提高,冻融稳定性极佳,透明度大为提高,但是抗剪切稳定性反而降低。在实验测定的温度下,羟丙基糯米粉糊呈现假塑性流体的特征且假塑性随醚化程度的提高而增强。应用试验表明其增稠效果好、稳定性高,可用做增稠稳定剂。  相似文献   
16.
An evaluation of the exhaust emissions from a compression ignition engine for fuels composed of 100 and 30% methyl esters of soy oil (SME) is described. These fuels were compared with a low-sulfur, petroleum #2 diesel fuel in a Caterpillar 3304, prechamber, 75 kW diesel engine, operated over heavy- and light-duty transient test cycles developed by the United States Bureau of Mines. More than 60 h of testing was performed on each fuel. The objective was to determine the influence of the fuels upon diesel particulate matter (DPM) and gaseous emissions. The effect of a modern diesel oxidation catalyst (DOC) also was determined in an effort to minimize emissions. Neat SME produced a higher volatile fraction of the DPM, but much less carbon soot fraction, leading to overall DPM reductions of 23 to 30% for the light- and heavy-duty transients. The DOC further reduced the volatile fraction and the total DPM. The SME fuel reduced gaseous emissions of CO by 23% and hydrocarbons by over 30% without increasing NOx. The DOC further reduced CO and hydrocarbon levels. Mutagenicity of the SME exhaust was low. Results indicate that SME fuel, used with a proper DOC, may be a feasible emission reduction technology for underground mines. References to specific products do not imply endorsement by the U.S. Bureau of Mines, a now defunct agency.  相似文献   
17.
对蒙脱土进行有机改性制得有机蒙脱土(OMMT),并制备了聚氯乙烯侑机蒙脱土/木粉(PVC/OMMT/WF)纳米复合材料。采用硅烷偶联剂对木粉表面进行改性,有效提高了聚氯乙烯/木粉(PVC/WF)复合材料的力学性能,其中加入1.5%(质量含量,下同)硅烷偶联剂可使复合材料的冲击强度和拉伸强度分别提高14.8%和18.5%。研究了OMMT的加入对木粉改性前后的PVC/WF复合材料力学性能、耐热性能及阻燃性能的影响,结果表明,木粉未经改性时,OMMT加入无助于PVC/OMMT/WF复合材料力学性能的提高;木粉用硅烷偶联剂改性后,添加少量的OMMT,可使PVC/OMMT/WF复合材料的冲击强度和拉伸强度明显提高。研究表明,添加OMMT可显著延迟复合材料的点燃时间,燃烧残余率也明显增加,OMMT是PVC/WF复合材料的高效阻燃剂。  相似文献   
18.
A new non-heating technique was developed for the sterilization of food stuff. Applying a roller compactor, ultra-high pressure sterilization has experimentally demonstrated its ability to sterilize dry powders, such as corn flour and Chinese herbs, with little quality deterioration. Also, the degree of food sterilization was found correlated well with the linear press forces between the rollers, roller gaps, and number of compaction passes. In comparison to the conventional high pressure sterilization technique, the new dry continuous processing method has the advantage of lower investment cost and is more versatile for sterilizing various food powders.  相似文献   
19.
Flaking and extruding dehulled soybeans were evaluated as a means of enhancing oil extraction efficiency during enzyme-assisted aqueous processing of soybeans. Cellulase, protease, and their combination were evaluated for effectiveness in achieving high oil extraction recovery from extruded flakes. Aqueous extraction of extruded full-fat soy flakes gave 68% recovery of the total available oil without using enzymes. A 0.5% wt/wt protease treatment after flaking and extruding dehulled soybeans increased oil extraction recovery to 88% of the total available oil. Flaking and extruding enhanced protease hydrolysis of proteins freeing more oil. Treating extruded flakes with cellulase, however, did not enhance oil extraction either alone or in combination with protease. Discrepancies in oil extraction recoveries were encountered when merely considering crude free fat because some oil became bound to denatured protein during extrusion and/or sample drying. Bound fat was unavailable for determination by using the hexane extraction method, but was accounted for by using the acid hydrolysis method for total oil determination. Oil extraction recovery from extruded soybean flakes was affected by oil determination methods, which was not the case for unextruded full-fat soy flour.  相似文献   
20.
表面处理对木粉增强PVC发泡复合板材性能的影响   总被引:9,自引:0,他引:9  
研究表面处理的木粉对发泡聚氯乙烯(PVC)板材的增强改性效果。使用铝酸酯偶联剂、丙烯酸丁酯预聚物对木粉进行表面处理,将其混合到聚氯乙烯发泡板材配料中进行板材加工生产,结果表明,经处理的木粉能提高发泡PVC板材的拉伸强度和冲击强度。用铝酸酯偶联剂处理木粉的发泡板材力学性能好于用丙烯酸丁酯预聚物处理的板材;而用丙烯酸丁酯预聚物处理木粉的复合材料在流变加工性能优于用铝酸酯处理木粉的复合材料。  相似文献   
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