全文获取类型
收费全文 | 69篇 |
免费 | 4篇 |
专业分类
化学 | 50篇 |
数学 | 4篇 |
物理学 | 19篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 2篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2003年 | 1篇 |
2001年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1974年 | 3篇 |
1935年 | 2篇 |
排序方式: 共有73条查询结果,搜索用时 15 毫秒
31.
L. W. Winkler E. Ekman A. Samyschlayewa W. Zimmermann K. Bodendorf N. Prileshajew L. Kofler F. Krämer P. HOrkheimer J. Reilly N. Noonan P. J. Drumm W. Peyer H. Iffinger S. Kroll W. J. Blackie J. F. Clevenger M. L. Pabst A. R. Bliss jun R. W. Morrison E. O. Prather jun 《Analytical and bioanalytical chemistry》1935,102(3-4):141-146
32.
33.
John Noonan 《Journal of Difference Equations and Applications》2013,19(4-5):355-377
Th powerful (and so far under-utilized) Goulden—Jackson Cluster method for finding the generating function for the number of words avoiding, as factors, the members of a prescribed set of ‘dirty words’, is tutorialized and extended in various directions. The authors' Maple implementations, contained in several Maple packages available from this paper's website www.math.temple.edu/zeilberg/gj.html, ar described and explained. 相似文献
34.
35.
36.
Anthony J. Varni Manami Kawakami Stephanie N. Kramer Megan Rice Steven J. Geib Linda A. Peteanu Tomasz Kowalewski Kevin J. T. Noonan 《Journal of polymer science. Part A, Polymer chemistry》2022,60(3):579-589
In this study, the impact of ester side group regiochemistry on electronic and conformational properties of regioregular polyfurans was explored. A derivative with alternating head-to-head and tail-to-tail orientation of the side groups was synthesized and compared with its head-to-tail analogue, and these were benchmarked against the related regioregular poly(3-hexylfurans). The study revealed that alkyl ester side groups in a head-to-head orientation will create significant steric strain as compared with linear alkyl chains with identical regiochemistry. Though the head-to-head ester side groups lead to twisting along the polymer backbone, they also produce a protective effect against photodegradation in comparison with a poly(3-hexylfuran). Altogether, the work highlights how side groups can impact conformational properties and stability of polyfurans. 相似文献
37.
Background
Our previous work described the neural processes of motor response inhibition during a stop signal task (SST). Employing the race model, we computed the stop signal reaction time (SSRT) to index individuals' ability in inhibitory control. The pre-supplementary motor area (preSMA), which shows greater activity in individuals with short as compared to those with long SSRT, plays a role in mediating response inhibition. In contrast, the right inferior prefrontal cortex (rIFC) showed greater activity during stop success as compared to stop error. Here we further pursued this functional differentiation of preSMA and rIFC on the basis of an intra-subject approach. 相似文献38.
The commonly observed 0.970 eV peak in the low-temperature photoluminescence from electron-irradiated Si is strongly suppressed in Ga-doped material. Another important peak at 0.790 eV is inhibited by Al doping. The present results are in conflict with previous identification of the defect responsible for the 0.790 eV peak. New luminescent bands observed only in samples with Al and Ga doping are reported. 相似文献
39.
Angular variations in the emission intensities of M2, 3VV (62 eV) Auger electrons from a Cu (110) surface have been measured. Large changes are observed as a function of both polar and azimuthal angles. Effects of the incident beam energy and angle of incidence have been determined, and interpretations of the the data are proposed. 相似文献
40.
Many environmental samples contain complex mixtures of organic compounds with different sources, polarities and reactivities. This study reports a method for the analysis of both polar/water-soluble and apolar organic compounds in several kinds of environmental samples. The analytical method consists of extraction with a mixture of dichloromethane:methanol (2:1, v/v), silylation using BSTFA (N,O-bis-(trimethylsilyl)trifluoroacetamide) and analysis by gas chromatography-mass spectrometry (GC-MS), a common device in chemical and environmental laboratories. Fifty individual sugar standards, including monosaccharides, sugar alcohols, anhydrosugars, disaccharides and trisaccharides, were analyzed for the determination of their fragmentation patterns and retention times. Recoveries (at three concentrations) and limits of detection (LOD) were determined for a standard mixture containing glucose (monosaccharide), sorbitol (sugar alcohol), levoglucosan (anhydrosugar) and sucrose (disaccharide), and they varied from 68 to 119% and 130 to 360 ng mL(-1), respectively. The method was used for the analysis of aerosol particle, soil and sediment samples, and demonstrated its feasibility in detecting not only several important environmental sugars (e.g., glucose, fructose, inositol, mannitol, sorbitol, levoglucosan, sucrose, mycose), but also a large range of organic compound classes from other polar components (e.g., dicarboxylic acids) to apolar compounds such as n-alkanes. Therefore, the analytical method presented here demonstrated its usefulness for a better understanding of sources and transport of various organic compounds in different environmental compartments. 相似文献