全文获取类型
收费全文 | 131篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 22篇 |
机械仪表 | 3篇 |
建筑科学 | 1篇 |
矿业工程 | 1篇 |
能源动力 | 2篇 |
轻工业 | 7篇 |
无线电 | 26篇 |
一般工业技术 | 23篇 |
冶金工业 | 28篇 |
自动化技术 | 24篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 1篇 |
2020年 | 3篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 1篇 |
2014年 | 3篇 |
2013年 | 4篇 |
2012年 | 4篇 |
2011年 | 4篇 |
2010年 | 1篇 |
2009年 | 2篇 |
2008年 | 7篇 |
2007年 | 9篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 7篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 10篇 |
1997年 | 4篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1985年 | 5篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1970年 | 5篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有137条查询结果,搜索用时 0 毫秒
131.
The repercussions of the cumulative industrial influx of CO2 into the atmosphere on the carbonate system of the sea have been examined. In accordance with earlier workers, an unsaturation state for CaCO3 seems inevitable in the mixed layer as a whole; however, a sizable part of the continental shelf, the region of maximum productivity of sea life, would still remain suitable for the growth of calcareous bodies. In view of the changing carbonate chemistry of the sea some general implications concerning marine carbonates are discussed. 相似文献
132.
Mrudul Gadhvi R. V. Upadhyay Kinnari Parekh R. V. Mehta 《Bulletin of Materials Science》2004,27(2):163-168
Texturing of two different magnetic fluids were carried out in paraffin wax under the influence of an external magnetic field.
The textured samples were characterized using magnetization measurement and a.c. susceptibility techniques. The results are
discussed in the light of ratio of anisotropic energy to magnetic and thermal energies. 相似文献
133.
The combustion method has been modified to increase the recovery of tritiated water after combustion of a tritium-labeled
tissue sample. This was accomplished by cooling the bottom of the combustion flask in a dry ice-acetone bath while irradiating
the top with an infrared lamp. The procedure resulted in at least 92% to 102% recovery of the tritiated water. The NCS solubilizer
was found to be superior to hyamine for solubilizing14C labeled tissue samples. The samples yielded light yellow-colored solutions when incubated for 15 hr at 50–55C. The counting
efficiency of this solution was 75% or higher. 相似文献
134.
B. B. Parekh P. M. Vyas Sonal R. Vasant M. J. Joshi 《Bulletin of Materials Science》2008,31(2):143-147
Oxalic acid metabolism is important in humans, animals and plants. The effect of oxalic acid sodium salt is widely studied
in living body. The growth of sodium oxalate single crystals by gel growth is reported, which can be used to mimic the growth
of crystals in vivo. The grown single crystals are colourless, transparent and prismatic. The crystals have been characterized by thermogravimetric
analysis, FT-IR spectroscopy and dielectric response at various frequencies of applied field. The crystals become anhydrous
at 129·3°C. Coats and Redfern relation is applied to evaluate the kinetic and thermodynamic parameters of dehydration. The
dielectric study suggests very less variation of dielectric constant with frequency of applied field in the range of 1 kHz-1
MHz. The nature of variation of imaginary part of complex permittivity, dielectric loss and a.c. resistivity with applied
frequency has been reported. 相似文献
135.
Major desalination processes consume a large amount of energy derived from oil and natural gas as heat and electricity. Solar desalination, although researched for over two decades, has only recently emerged as a promising renewable energy-powered technology for producing fresh water. Solar desalination based on the humidification-dehumidification cycle presents the best method of solar desalination due to overall high-energy efficiency. This paper provides a comprehensive technical review of solar desalination with a multi-effect cycle providing a better understanding of the process. Discussion on methods to improve system performance and efficiency paves the way towards possible commercialisation of such units in the future. 相似文献
136.
137.
Angiotensin converting enzyme 2 (ACE2) is a critical component of the compensatory axis of the renin angiotensin system. Alterations in ACE2 gene and protein expression, and activity mediated by A Disintegrin And Metalloprotease 17 (ADAM17), a member of the “A Disintegrin And Metalloprotease” (ADAM) family are implicated in several cardiovascular and neurodegenerative diseases. We previously reported that activation of kinin B1 receptor (B1R) in the brain increases neuroinflammation, oxidative stress and sympathoexcitation, leading to the development of neurogenic hypertension. We also showed evidence for ADAM17-mediated ACE2 shedding in neurons. However, whether kinin B1 receptor (B1R) activation has any role in altering ADAM17 activity and its effect on ACE2 shedding in neurons is not known. In this study, we tested the hypothesis that activation of B1R upregulates ADAM17 and results in ACE2 shedding in neurons. To test this hypothesis, we stimulated wild-type and B1R gene-deleted mouse neonatal primary hypothalamic neuronal cultures with a B1R-specific agonist and measured the activities of ADAM17 and ACE2 in neurons. B1R stimulation significantly increased ADAM17 activity and decreased ACE2 activity in wild-type neurons, while pretreatment with a B1R-specific antagonist, R715, reversed these changes. Stimulation with specific B1R agonist Lys-Des-Arg9-Bradykinin (LDABK) did not show any effect on ADAM17 or ACE2 activities in neurons with B1R gene deletion. These data suggest that B1R activation results in ADAM17-mediated ACE2 shedding in primary hypothalamic neurons. In addition, stimulation with high concentration of glutamate significantly increased B1R gene and protein expression, along with increased ADAM17 and decreased ACE2 activities in wild-type neurons. Pretreatment with B1R-specific antagonist R715 reversed these glutamate-induced effects suggesting that indeed B1R is involved in glutamate-mediated upregulation of ADAM17 activity and ACE2 shedding. 相似文献