全文获取类型
收费全文 | 168篇 |
免费 | 22篇 |
国内免费 | 20篇 |
专业分类
化学 | 117篇 |
晶体学 | 2篇 |
力学 | 7篇 |
数学 | 7篇 |
物理学 | 77篇 |
出版年
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 2篇 |
2020年 | 7篇 |
2019年 | 2篇 |
2018年 | 6篇 |
2017年 | 1篇 |
2016年 | 11篇 |
2015年 | 10篇 |
2014年 | 7篇 |
2013年 | 6篇 |
2012年 | 12篇 |
2011年 | 9篇 |
2010年 | 3篇 |
2009年 | 10篇 |
2008年 | 7篇 |
2007年 | 10篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 4篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 7篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有210条查询结果,搜索用时 15 毫秒
1.
Yonggang Shangguan Li Zhao Liyang Tao Qiang Zheng 《Journal of Polymer Science.Polymer Physics》2007,45(13):1704-1712
The effects of preparation method, composition, and thermal condition on formation of β‐iPP in isotactic polypropylene/ethylene–propylene rubber (iPP/EPR) blends were studied using modulated differential scanning calorimeter (MDSC), wide angle X‐ray diffraction (WAXD), and phase contrast microscopy (PCM). It was found that the α‐iPP and β‐iPP can simultaneity form in the melt‐blended samples, whereas only α‐iPP exists in the solution‐blended samples. The results show that the formation of β‐iPP in the melt‐blended samples is related to the crystallization temperature and the β‐iPP generally diminishes and finally vanishes when the crystallization temperature moves far from 125 °C. The phenomena that the lower critical temperature of β‐iPP in iPP/EPR obviously increases to 114 °C and the upper critical temperature decreases to 134 °C indicate the narrowing of temperature interval, facilitating the formation of β‐iPP in iPP/EPR. Furthermore, it was found that the amount of β‐iPP in melt‐blended iPP/EPR samples is dependent on the composition and the maximum amount of β‐iPP formed when the composition of iPP/EPR blends is 85:15 in weight. The results through examining the effect of annealing for iPP/EPR samples at melt state indicate that this annealing may eliminate the susceptibility to β‐crystallization of iPP. However, only α‐iPP can be observed in solution‐blended samples subjected to annealing for different time. The PCM images demonstrate that an obvious phase‐separation happens in both melt‐blended and solution‐blended iPP/EPR samples, implying that compared with the disperse degree of EPR in iPP, the preparation method plays a dominant role in formation of β‐iPP. It is suggested that the origin of formation of β‐iPP results from the thermomechanical history of the EPR component in iPP/EPR. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1704–1712, 2007 相似文献
2.
Soderstrom E McKenna JA Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R 《Physical review letters》1990,64(25):2980-2983
3.
Komamiya S Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gatto C Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R 《Physical review letters》1990,64(24):2881-2884
4.
5.
6.
7.
8.
9.
10.
Hongmin Liu Xiaojiang Ye Zhiwei Lian Yuangao Wen Wenfeng Shangguan 《Research on Chemical Intermediates》2006,32(1):9-16
Formaldehyde is one of the most harmful pollutants that endanger occupants' health and the way of its effective removal has
become a focus in the field of air quality. This paper studies the static photocatalytic removal of formaldehyde experimentally
and finds out that carbon monoxide, which is more harmful to occupants' health than the formaldehyde itself, is one of the
by-products in the process of photocatalytic oxidation of formaldehyde. The increase of carbon monoxide concentration should
be taken into consideration in the photocatalytic application. The photocatalyst surface at room temperature can weakly adsorb
CO and CO2, which can deactivate the photocatalysts. 相似文献