全文获取类型
收费全文 | 68篇 |
免费 | 0篇 |
专业分类
化学 | 38篇 |
力学 | 1篇 |
数学 | 4篇 |
物理学 | 25篇 |
出版年
2018年 | 1篇 |
2017年 | 1篇 |
2012年 | 3篇 |
2011年 | 2篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 2篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 7篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1975年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有68条查询结果,搜索用时 15 毫秒
1.
CV Tomy D Pal SS Banerjee S Ramakrishnan AK Grover S Bhattacharya MJ Higgins G Balakrishnan McK Paul 《Pramana》2002,58(5-6):925-935
The weakly pinned single crystals of the hexagonal 2H-NbSe2 compound have emerged as prototypes for determining and characterizing the phase boundaries of the possible order-disorder
transformations in the vortex matter. We present here a status report based on the ac and dc magnetization measurements of
the peak effect phenomenon in three crystals of 2H-NbSe2, in which the critical current densities vary over two orders of magnitude. We sketch the generic vortex phase diagram of
a weakly pinned superconductor, which also utilizes theoretical proposals. We also establish the connection between the metastability
effects and pinning. 相似文献
2.
Alberti G Brunet E Dionigi C Juanes O de La Mata MJ Rodríguez-Ubis JC Vivani R 《Angewandte Chemie (International ed. in English)》1999,38(22):3351-3353
The hydrophilic oxygen atoms of polyethylenoxide chains inserted as pillars in gamma-zirconium phosphate form hydrogen bonds with the acid groups of the host. As a result the pillars are almost perpendicular to the gamma layers. Upon changing the pH level of the supernatant solution the hydrogen bonds are broken and the pillars become almost perpendicular to the layers (shown schematically). Thus there is a reversible enlargement-shortening of the interlayer space. 相似文献
3.
The pyrolyses of silyl esters of pyruvic acid and phenylglyoxylic acid gave rise to acylsilanes in high yield. An intramolecular rearrangement involving an intermediate siloxycarbene is proposed to account for the reaction. 相似文献
4.
5.
6.
The 29Si and 14N nmr spectra of some bissilylamides and monosilylamides are reported. The results are compared with those for model silylesters, amines and imines. The compound of formula CF3CONCH3Si(CH3)3 (MSTFA) is shown to exist as a tautemeric mixture of a silylamide and a silylimidate. This assignment is confirmed by 13C nmr. A rationale is proposed for the structure directing effect of substituents on the amide carbon atom. 相似文献
7.
8.
Bassindale AR MacKinnon IA Maesano MG Taylor PG 《Chemical communications (Cambridge, England)》2003,(12):1382-1383
Hexasilsesquioxane cages (T6) have been prepared from a range of alkyl and aryl trichlorosilanes using a "non aqueous" hydrolysis with dimethyl sulfoxide. 相似文献
9.
Benzylpiperazine (BZP) is an amphetamine-type stimulant, which was legally available in New Zealand and widely used in “Party
Pills” until reclassification as a Class C drug in April 2008. BZP was included as part of a multi-analyte method developed
for hair screening using high-performance liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS). A 20-mg sample
of hair is extracted and partially purified using mixed-mode solid-phase extraction cartridges prior to analysis by LC-MS/MS.
The method was developed as a broad screen for drugs of abuse (including amphetamines, opiates, and benzodiazepines), with
only the BZP results being presented here. The assay was validated and found to be linear over the range of 0.085 to 8.65 ng/mg
with correlation coefficient of r
2 ≥ 0.99. Blank hair samples spiked with BZP at 0.22 and 2.16 ng/mg gave intra- and inter-day precision coefficients of variation
of ≤10% (n = 6 per day, 3 days) at both levels and calculated extraction efficiencies of 78% and 91%, respectively. The results from
the samples submitted to the laboratory for BZP analysis showed 11% were positive (n = 126). The mean BZP level was 3.9 ng/mg (range, 0.4–33 ng/mg; the result was extrapolated when above the calibration). These
data are the first available showing the levels expected from users of BZP. 相似文献
10.