全文获取类型
收费全文 | 118篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
化学 | 53篇 |
数学 | 35篇 |
物理学 | 31篇 |
出版年
2021年 | 3篇 |
2020年 | 3篇 |
2014年 | 2篇 |
2012年 | 3篇 |
2011年 | 10篇 |
2010年 | 2篇 |
2008年 | 2篇 |
2007年 | 9篇 |
2006年 | 5篇 |
2005年 | 5篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 1篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 9篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 3篇 |
1965年 | 1篇 |
排序方式: 共有119条查询结果,搜索用时 15 毫秒
91.
92.
J. K. Stille J. J. Hillman 《Journal of polymer science. Part A, Polymer chemistry》1967,5(8):2067-2077
The meso- and d,l-diastereomers of o-bis(epoxyethyl)benzene have been synthesized and identified. The diastereomers were polymerized by a variety of catalysts to give a polymer which has mainly isochroman recurring units as a result of a cyclopolymerization mechanism. Some features of the polymerization with the triisobutylaluminum catalyst system have been studied. The rates of polymerization of the monomers and the transition temperatures of the resulting polymers have been determined. The results are explained on the basis of a controlled intramolecular propagation and a stereospecific polymerization. 相似文献
93.
Pevsner PH Naftolin F Hillman DE Miller DC Fadiel A Kogus A Stern A Samuels HH 《Rapid communications in mass spectrometry : RCM》2007,21(3):429-436
The purpose of this study is to determine the feasibility of the direct matrix-assisted laser desorption/ionization (MALDI) identification of proteins in fixed T47D breast cancer cells and murine brain tissues. The ability to identify proteins from cells and tissue may lead to biomarkers that effectively predict the onset of defined disease states, and their dynamic behavior could be an important hint for drug target discoveries. Direct tissue application of trypsin allows protein identification in cells and tissues, while maintaining spatial integrity and intracellular organization. Using a chemical printer, matrix was co-registered on trypsinized human T47D breast cancer cells and cryo-preserved sections of murine brain tissue, followed by MALDI post-source decay (PSD) or MALDI collision-induced dissociation (CID), respectively. Mass-to-charge (m/z) data from the cells and brain tissues were processed using Mascot software interrogation of the National Center for Biotechnology Information (NCBI) database. Histone H2B was identified from cultured T47D human breast cancer cells. Tubulin beta2 was identified from mouse brain cortex following an induced stroke. These results suggest that MALDI PSD/CID, combined with bioinformatics, can be used for the direct identification of proteins from cells and tissues. Refinements in preparation techniques may improve this approach to provide a tool for quantitative proteomics and clinical analysis. 相似文献
94.
A. Robert Hillman Magdalena A. Skopek Stephen J. Gurman 《Journal of Solid State Electrochemistry》2010,14(11):1997-2010
XAS (EXAFS and XANES), XPS and IR spectroscopies were used to extract redox compositional and structural information on films
of electrodeposited Co and Ni hexacyanoferrates whose redox state was manipulated electrochemically. The X-ray methods provided
direct information on the metal species and IR provided indirect information via the behaviour of the ligand vibration. XPS
responses showed that the electrochemical response of Co hexacyanoferrate is attributable to Co (except for a small amount
of FeII oxidation at very positive potentials), and of Ni hexacyanoferrate to Fe; XANES edge shifts confirm these deductions. Local
structure around the metal atoms was extracted from EXAFS data in terms of M′–N, M′–C and M′–Fe (M′ = Co or Ni) distances
and the associated Debye-Waller factors as functions of film charge state. For Co hexacyanoferrate, the redox variation of
static disorder was consistent with a molecular model involving discrete CoII and CoIII sites, whose populations respond to potential, but not with a solid-state model. 相似文献
95.
Stepp CE Hillman RE Heaton JT 《The Journal of the Acoustical Society of America》2010,127(5):3166-3176
A simple, one degree of freedom virtual trajectory model of vocal fold kinematics was developed to investigate whether kinematic features of vocal fold movement confirm increased muscle stiffness. Model simulations verified that increases in stiffness were associated with changes in kinematic parameters, suggesting that increases in gesture rate would affect kinematic features to a lesser degree in vocal hyperfunction patients given the increased levels of muscle tension they typically employ to phonate. This hypothesis was tested experimentally in individuals with muscle tension dysphonia (MTD; N = 10) and vocal nodules (N = 10) relative to controls with healthy normal voice (N = 10) who were examined with trans-nasal endoscopy during a simple vocal fold abductory-adductory task. Kinematic measures in MTD patients were less affected by increased gesture rate, consistent with the hypothesis that these individuals have elevated typical laryngeal muscle tension. Group comparisons of the difference between medium and fast gesture rates (Mann-Whitney, one-tailed) showed statistically significant differences between the control and MTD individuals on the two kinematic features examined (p<0.05). Results in nodules participants were mixed and are discussed independently. The findings support the potential use of vocal fold kinematics as an objective clinical assay of vocal hyperfunction. 相似文献
96.
97.
We show that an infinite cyclic covering space M′ of a PD
n
-complex M is a PD
n-1-complex if and only if χ(M) = 0, M′ is homotopy equivalent to a complex with finite [(n−1)/2]-skeleton and π1(M′) is finitely presentable. This is best possible in terms of minimal finiteness assumptions on the covering space. We give
also a corresponding result for covering spaces M
ν with covering group a PD
r
-group under a slightly stricter finiteness condition.
相似文献
98.
Sojeong Kim Eun-Young Lee Prima F. Hillman Jaeyoung Ko Inho Yang Sang-Jip Nam 《Molecules (Basel, Switzerland)》2021,26(8)
Salicornia europaea L. is a halophyte that grows in salt marshes and muddy seashores, which is widely used both as traditional medicine and as an edible vegetable. This salt-tolerant plant is a source of diverse secondary metabolites with several therapeutic properties, including antioxidant, antidiabetic, cytotoxic, anti-inflammatory, and anti-obesity effects. Therefore, this review summarizes the chemical structure and biological activities of secondary metabolites isolated from Salicornia europaea L. 相似文献
99.
A. Robert Hillman David C. Loveday Andrew Glidle Johannes G. Vos Alan P. Clarke David Kelly Stanley Bruckenstein 《Macromolecular Symposia》1994,80(1):323-335
Electrochemical quartz crystal microbalance measurements are reported for redox switching of thin films of three macromolecule-metal complexes: poly(vinylferrocene) (PVF), 10% osmium-functionalized poly(vinylpyridine) (Os-PVP), and 10% osmium functionalized poly(vinylpyridine-co-styrene) (Os-PVP-co-PS). The data provide insight into the ion and solvent transfer processes associated with electron transfer between the electrode and the electroactive film. Four important parameters are identified: electrolyte composition, (co)polymer composition, prior film history and experimental time scale. 相似文献
100.