全文获取类型
收费全文 | 93篇 |
免费 | 10篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 26篇 |
机械仪表 | 1篇 |
建筑科学 | 5篇 |
能源动力 | 6篇 |
轻工业 | 2篇 |
水利工程 | 7篇 |
无线电 | 3篇 |
一般工业技术 | 30篇 |
冶金工业 | 2篇 |
自动化技术 | 20篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2012年 | 11篇 |
2011年 | 6篇 |
2010年 | 6篇 |
2009年 | 10篇 |
2008年 | 4篇 |
2007年 | 5篇 |
2006年 | 8篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有103条查询结果,搜索用时 0 毫秒
101.
Georgia Antonopoulou Hariklia N. Gavala Ioannis V. Skiadas Gerasimos Lyberatos 《International Journal of Hydrogen Energy》2010
The present study focused on the influence of pH on the fermentative hydrogen production from the sugars of sweet sorghum extract, in a continuous stirred tank bioreactor. The reactor was operated at a Hydraulic Retention Time of 12 h and a pH range of 3.5–6.5. The maximum hydrogen production rate and yield were obtained at pH 5.3 and were 1752 ± 54 mL H2/d or 3.50 ± 0.07 L H2/L reactor/d and 0.93 ± 0.03 mol H2/mol glucose consumed or 10.51 L H2/kg sweet sorghum, respectively. The main metabolic product at this pH value was butyric acid. The hydrogen productivity and yield were still at high levels for the pH range of 5.3–4.7, suggesting a pH value of 4.7 as optimum for hydrogen production from an economical point of view, since the energy demand for chemicals is lower at this pH. At this pH range, the dominant fermentation product was butyric acid but when the pH culture sharply decreased to 3.5, hydrogen evolution ceased and the dominant metabolic products were lactic acid and ethanol. 相似文献
102.
Panayiotis V. Ioannou Maria A. Lala Gerasimos M. Tsivgoulis 《European Journal of Lipid Science and Technology》2011,113(11):1357-1362
Pure tetraesters of erythritol with C10, C12, C14, C16, C18 saturated, and C18:1 unsaturated (oleoyl) fatty acyl chains have been prepared for the first time and characterized using the acylating systems fatty acid/N,N′‐dicyclohexylcarbodiimide/4‐dimethylaminopyridine (DMAP), fatty acid anhydride/DMAP, fatty acyl chloride/pyridine, and fatty acyl chloride/boron trifluoride etherate. For the first three systems the yields were in the range of 80–90% while the fatty acyl chloride/pyridine system has the advantage of lower cost. The fatty acyl chloride/boron trifluoride etherate system gave lower (ca 70%) yields of the tetraesters. The tetraesters of erythritol may have applications analogues to those of triglycerides. In addition, new applications can be envisaged for these compounds, as a result of their differences in physical, chemical, and biochemical properties compared to triglycerides. Practical applications: The tetraesters of erythritol with saturated fatty acyl chains may have applications analogous to those of saturated triglycerides. However, tetraesters with unsaturated fatty acid chains may have greater prospects of having industrial uses after doing chemistry on the carbon–carbon double bonds. 相似文献
103.
Sombolos KI Christidou FN Bamichas GI Gionanlis LD Karagianni AC Anagnostopoulos TC Natse TA 《Hemodialysis international. International Symposium on Home Hemodialysis》2006,10(1):88-93
We report a new and simple way that can reveal the presence of vascular access recirculation (VAR) in patients undergoing hemodialysis (HD). Acid-base and blood gas parameters (pH, pO(2), pCO(2), and HCO(3)) were measured in blood samples drawn from an arterial fistula needle before the initiation of HD and from arterial and venous lines simultaneously 5 min later, in 31 patients (group A). Vascular access recirculation was measured using the glucose infusion test (GIT) immediately after the withdrawal of the 5-min samples. The same study was repeated in 30 patients in whom HD lines were reversed (group B). A comparison with baseline (predialysis) values of an analysis of the arterial line in group A at 5 min revealed that pCO(2) increased by 1.14+/-2.5 mmHg and HCO(3) by 0.6+/-0.6 mM/L (p<0.02 and p<0.00001, respectively). The corresponding pO(2) and pH values did not show significant differences. Glucose infusion test at 5 min (GITa) was -0.058+/-0.03%. A comparison with baseline (predialysis) values of an analysis of the arterial line in group B at 5 min revealed that pCO(2) increased by 7.7+/-3.5 mmHg and HCO(3) by 2.9+/-1.0 mM/L (p<0.000001 in each case). The pH level was significantly lower in comparison with baseline values (p<0.00001), while pO(2) did not show a significant difference. Glucose infusion test at 5 min (GITb) was 12.0+/-6.1% (p<0.000001 in comparison with GITa values). Clinically significant VAR was defined as HCO(3) increment >1.8 mM/L, based on the receiver-operating characteristics curve, which showed a threshold value of HCO(3) increment >1.8 mmol/L as a predictor of GIT recirculation. Five minutes after the initiation of high-flux HD with a 0 ultrafiltration rate, there is a small increment in arterial HCO(3) values relative to predialysis values. Clinically significant VAR is present when this increment is higher than 1.8 mM/L. 相似文献