全文获取类型
收费全文 | 3903篇 |
免费 | 217篇 |
国内免费 | 17篇 |
专业分类
电工技术 | 37篇 |
综合类 | 6篇 |
化学工业 | 848篇 |
金属工艺 | 119篇 |
机械仪表 | 136篇 |
建筑科学 | 215篇 |
矿业工程 | 17篇 |
能源动力 | 277篇 |
轻工业 | 542篇 |
水利工程 | 33篇 |
石油天然气 | 25篇 |
无线电 | 266篇 |
一般工业技术 | 683篇 |
冶金工业 | 190篇 |
原子能技术 | 59篇 |
自动化技术 | 684篇 |
出版年
2024年 | 23篇 |
2023年 | 53篇 |
2022年 | 91篇 |
2021年 | 135篇 |
2020年 | 138篇 |
2019年 | 112篇 |
2018年 | 208篇 |
2017年 | 170篇 |
2016年 | 212篇 |
2015年 | 126篇 |
2014年 | 209篇 |
2013年 | 495篇 |
2012年 | 227篇 |
2011年 | 269篇 |
2010年 | 208篇 |
2009年 | 309篇 |
2008年 | 192篇 |
2007年 | 178篇 |
2006年 | 127篇 |
2005年 | 74篇 |
2004年 | 71篇 |
2003年 | 52篇 |
2002年 | 57篇 |
2001年 | 47篇 |
2000年 | 36篇 |
1999年 | 25篇 |
1998年 | 51篇 |
1997年 | 26篇 |
1996年 | 26篇 |
1995年 | 18篇 |
1994年 | 23篇 |
1993年 | 11篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1986年 | 6篇 |
1985年 | 9篇 |
1984年 | 8篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1979年 | 10篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1965年 | 3篇 |
1960年 | 5篇 |
排序方式: 共有4137条查询结果,搜索用时 15 毫秒
81.
European Journal of Wood and Wood Products - Medium density fibreboards (MDF) are currently not recycled after service life, but various publications report on recycling by the disintegration of... 相似文献
82.
83.
Mustafa Şengül Tuba Erkaya Muhammet Dervişoğlu Oğuz Aydemir Osman Gül 《International Journal of Dairy Technology》2014,67(3):373-383
In the present study, biochemical, chemical and texture changes in Tulum cheeses made using calf rennet and microbial rennets (Aspergillus niger protease and Rhizomucor miehei protease) were compared during ripening for up to 90 days. A total of 15 free fatty acids (FFAs) were detected in the cheese samples. The peroxide values (PV) of the cheeses increased significantly (P < 0.05) during ripening and the cheese made with calf rennet had the highest PV. Proteolysis in the cheeses increased as the ripening time increased. αs1‐casein and β‐casein degradation was higher in cheeses manufactured with R. miehei protease. Cheeses made with calf rennet were significantly (P < 0.05) harder, more adhesive, more cohesive and more resilient than those made with microbial rennet. 相似文献
84.
85.
86.
87.
Different starter culture added groups (Group I: Lactobacillus sake, Staphylococcus xylosus; Group II: Lactobacillus plantarum, Staphylococcus carnosus; Group III: Lactobacillus curvatus, Staphylococcus carnosus, and Staphylococcus xylosus) and control group sausage samples were produced experimentally at two different temperatures (22 and 26 °C). In raw materials and all groups, by the 0th, 2nd, 5th and 7th days of the ripening period, the analysis of HPLC and biogenic amine (tyramine, histamine, cadaverine, putrescine, phenylethylamine, tryptamine, spermine, and spermidine) amounts, microbiological (Lactic acid bacteria, Micrococcus/Staphylococcus, Enterobacteriaceae, Enterococcus spp., and moulds–yeasts) and chemical (pH, dry matter, and salt) have been done. During the ripening period, there is no statistical discrepancy (P > 0.05) in terms of biogenic amine amounts, microbiological, and chemical values detected from the sausage samples produced at 26 and 22 °C. However, in both levels of temperature, there is statistical discrepancy (P < 0.001) detected in terms of tyramine, putrescine values and the count of Enterococcus spp. between the starter culture added samples and control group samples. By this study, it has been stated that the ripening temperature does not make any statistical discrepancy (P > 0.05) for all values but the use of starter culture prevents the formation of biogenic amine in Turkish fermented sausages. 相似文献
88.
One of the most important spoilage factors of foods is molds. Therefore, it is important to determine the presence of mold in foods quickly because of the deterioration of aroma, flavor, appearance, and textural structure as well as the mycotoxins, which are toxic secondary metabolites of molds. Twenty-five percent of agricultural products worldwide are infected with mycotoxins directly or indirectly. With the global population increasingly rising, the need for access of safe and adequate food in the future has great importance. Quantification of ergosterol, a constituent of the membrane of molds and a precursor of vitamin D2, is a feasible method for determination of fungal contamination in foods. The aim of this review is to discuss the possibility of using ergosterol as an indicator of mold growth in foods. 相似文献
89.
90.
İnci Türk Toğrul 《International Journal of Food Science & Technology》2010,45(6):1146-1152
In this work, heat and moisture transport occurred during drying of black grapes in a laboratory dryer were investigated. In the experiments, the air was passed through the chamber at a variety of flow rates (0.5, 0.75, 1.0 and 1.25 m s?1) and temperatures (40, 50, 60 and 70 °C). Thermal and moisture diffusivities were determined. The possibility of expressing the moisture removal from the grapes was searched with the fourteen one‐layer drying models selected from the literature. Among all the models, the Page model was found the best for explaining the experimental results. The effects of the drying temperature and air velocity on the constants and coefficients of Page model and diffusivities were also investigated by multiple combinations of the different equations as the linear, power, logarithmic, exponential, polynomial, inverse polynomial and Arrhenius type by non‐ linear regression analyses. Models obtained were also analysed statistically using t‐test, RMSE, MBE and χ2. 相似文献