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531.
532.
Hiromi Yoshida Yuka Tomiyama Megumi Tanaka Yoshiyuki Mizushina 《Journal of the science of food and agriculture》2007,87(14):2709-2714
BACKGROUND: The fatty acid distribution of triacylglycerols (TAG) and major phospholipids (PL) obtained from four varieties of peas (Pisum sativum) was investigated. The total lipids extracted from the peas were separated by thin layer chromatography into seven fractions. RESULTS: The major lipid components were PL (52.2–61.3%) and TAG (31.2–40.3%), while hydrocarbons, steryl esters, free fatty acids and diacylglycerols (sn‐1,3 and sn‐1,2) were also present in minor proportions (5.6–9.2%). The main PL components isolated from the four varieties were phosphatidylcholine (42.3–49.2%), phosphatidylinositol (23.3–25.2%) and phosphatidylethanolamine (17.7–20.5%). Significant differences (P < 0.05) in fatty acid distribution were found for different pea varieties. Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among the three PL. However, the principal characteristics of the fatty acid distribution in the TAG and three PL were evident among the four varieties: unsaturated fatty acids were predominantly located in the sn‐2 position while saturated fatty acids primarily occupied the sn‐1 or sn‐3 position in the oils of the peas. CONCLUSION: These results should be useful to both producers and consumers for the manufacture of pea foods in Japan. Copyright © 2007 Society of Chemical Industry 相似文献
533.
ABSTRACT: Green peas were submitted to osmotic pretreatments in carbohydrate-salt syrups to evaluate the effect of alternative agents on quality and assess the stabilization accomplished during subsequent storage in a wide temperature range-down to −24°C, including the −3 to −12°C detrimental zone. Green color and L-ascorbic acid loss were kinetically studied, and their temperature dependence was modeled by Arrhenius and Will-iams-Landel-Ferry equations. Dehydrofrozen samples exhibited significantly improved stability, with the rate of L-ascorbic acid loss, being reduced by as much as 3-fold for peas osmotically pretreated with oligofructose, trehalose, and maltitol systems. The cryostabilization results are discussed in relation to glass transition behavior of the modified osmodehydrofrozen food matrix. 相似文献
534.
Legume starches were compared for physicochemical properties that may explain differences in functional properties. Field pea starch had higher amylose, greater swelling power and solubility, and lower pasting temperatures than pinto and navy bean starches. Scanning electron microscopy (SEM) showed that field pea starch had larger, more irregularly shaped granules and more broken large granules than pinto or navy starches. The most starch damage was observed for field pea. Pinto and navy bean starches had greater resistance to swelling at 60°C than field pea indicating a more strongly bonded micellar network. Higher cold paste viscosity was observed for navy bean and field pea. 相似文献
535.
文章针对目前国际市场要求固体融雪盐产品品质高,粒度要求不尽相同的特点,研制适应滩区作业环境使用的轻型融雪盐筛分设备,不但使产品适应国际市场的需求,而且为企业带来较好的经济效益。 相似文献
536.
537.
Witoon Prinyawiwatkul Kay H. McWatters Larry R. Beuchat R. Dixon Phillips Dr. Mark A. Uebersak 《Critical reviews in food science and nutrition》1996,36(5):413-436
Cowpeas (Vigna unguiculata L. Walp) are an important grain legume in East and West African countries as well as in other developing countries. The U.S. is the only developed country producing large amounts of cowpeas. High protein (18 to 35%) and carbohydrate (50 to 65%) contents, together with an amino acid pattern complementary to that of cereal grains, make cowpeas potentially important to the human diet from a nutritional standpoint. Despite their potential as an inexpensive source of protein and energy, cowpeas are underutilized in the U.S. and other industrialized countries. A simple technology for preparing cowpea flour would stimulate increased consumption of this legume. This paper reviews the status of cowpea flour production technologies and uses of cowpea flour in various food products. 相似文献
538.
为分析有机融雪剂对沥青性能的影响及其作用机理,测定腐蚀后沥青三大指标和黏度,对比腐蚀前后沥青宏观表面特征和微观相态参数的变化,并基于Verhulst模型量化沥青腐蚀周期内针入度的变化.结果 表明:有机融雪剂与沥青发生相似相溶,削弱了沥青的高、低温性能和抗老化性能;有机融雪剂腐蚀后基质沥青表面出现腐蚀孔和溶解坑,荧光显微试验表明SBS分子经浸泡腐蚀后出现明显"线性"和"块状"团聚,导致沥青微观结构参数(孔隙面积和直径)发生不同程度的改变;腐蚀后沥青针入度变化符合Verhulst模型. 相似文献
539.
为了保证结构服役安全,有必要对不均匀积雪荷载作用下网架结构工作状态进行分析。采用CFD数值模拟技术,基于准动态网格划分方法,以一正放四角锥网架结构为研究背景,分析了网架结构在持续降雪24 h中的屋面不均匀积雪分布变化情况,并详细探讨了不同风向角和不同风速对网架屋面积雪分布变化情况的影响; 最后建立了该网架结构的有限元模型,分析了不同雪荷载工况的结构工作状态。结果表明:与其他有风条件下的工况相比,风速为12 m?s-1、风向角为90°时的结构屋面平均雪压和积雪沉积区域占比最大,因此它是结构的最不利工况,该工况的平均雪压是无风条件下均布积雪平均雪压的88.9%,但结构杆件的最大应力值及挠度值却较均布积雪作用时有所增加,而且部分杆件从受拉杆变为受压杆; 风致不均匀积雪是网架结构在服役期间的安全隐患,应在工程设计中予以重视。 相似文献
540.