全文获取类型
收费全文 | 59篇 |
免费 | 1篇 |
专业分类
化学 | 40篇 |
晶体学 | 1篇 |
力学 | 2篇 |
数学 | 2篇 |
物理学 | 15篇 |
出版年
2021年 | 1篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2012年 | 4篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1957年 | 2篇 |
1956年 | 4篇 |
1955年 | 2篇 |
1937年 | 2篇 |
排序方式: 共有60条查询结果,搜索用时 15 毫秒
1.
It is shown unequivocally by chemical correlations (cf. Schemes 1--3) and Raman optical activity spectra (cf. Fig. 1 and 2) that the (R)-configuration has to be attributed to (+)-1-methylindane ((+)- 1 ). This is in contradiction to an earlier assignment of the (R)-configuration to (?)- 1 [2] which was based on the (R)-configuration of (+)-indane-1-carboxylic acid ( 3 ) [11]. 相似文献
2.
(?)-(S)- and (+)-(R)-3-methylcyclopentene (1) has been prepared in a stereochemically unambiguous synthesis. The (S)-configuration for (?)-1 was confirmed by correlation with (?)-(S)-1-methylindane. 相似文献
3.
Commercially available plastic films have been examined, in the spectral range up to 1200 cm−1, for use as a beam splitter in far-infrared Michelson interferometers. The materials reported include polyethylene terephthalate,
polycarbonate, polyvinylchloride, polypropylene, cellulose and polyethylene. 相似文献
4.
Tams Pfeil 《Applied Mathematical Modelling》2008,32(8):1599-1606
Let us consider the heat conduction problem described by a parabolic equation. We study under which conditions is the time-dependence on the boundary preserved inside the solid. The question is how information entering on the boundary penetrates the solid. E.g. consider a heat conducting solid subject to sinusoidally varying boundary condition. After decay of the transients, the temperature at any inner point varies in time sinusoidally with the same circular frequency, with space dependent amplitude and phase delay. So, sinusoidal signals inserted on the boundary are preserved. Information is also preserved in case of linear signals. Farkas and Mudri [H. Farkas, I. Mudri, Shape-preserving time-dependences in heat conduction, Acta Phys. Hung. 55 (1984) 267–273] have formulated this phenomenon, defined the notion of the boundary following solution and the shape-preserving signal forms, determined necessary and heuristic sufficient conditions for the shape-preserving signal forms.
Their work is extended by rigorous proofs of some sufficient conditions in this paper, and the minimum of the phase delay, expected to be attained on the boundary for physical reasons, is examined. 相似文献
5.
H. Wartenberg E. Pfeil und D. Du Rietz 《Fresenius' Journal of Analytical Chemistry》1937,109(1-2):76-79
Ohne Zusammenfassung 相似文献
6.
Boundary layer transition with and without transitional separation bubbles was investigated on a cylinder in cross flow. Measurements of the pressure distribution and hot-wire measurements within the boundary layer were carried out at two free-stream velocities and with different flow disturbances. The separation bubble reacts very sensitively to changes in inlet turbulence. Tollmien-Schlichting waves were observed in the separated shear layer just before transition, and their frequencies were in good agreement with stability theory. However, correlations concerning bubble length which were fitted using airfoil data are apparently not suitable for describing separation bubbles on cylinders. Finally, measurements in periodically disturbed flow show how the bubble reacts to this type of disturbance. 相似文献
7.
Ana Candalija Thomas Scior Hans-Richard Rackwitz Jordan E. Ruiz-Castelan Ygnacio Martinez-Laguna Jos Aguilera 《Molecules (Basel, Switzerland)》2021,26(13)
This article presents experimental evidence and computed molecular models of a potential interaction between receptor domain D5 of TrkB with the carboxyl-terminal domain of tetanus neurotoxin (Hc-TeNT). Computational simulations of a novel small cyclic oligopeptide are designed, synthesized, and tested for possible tetanus neurotoxin-D5 interaction. A hot spot of this protein-protein interaction is identified in analogy to the hitherto known crystal structures of the complex between neurotrophin and D5. Hc-TeNT activates the neurotrophin receptors, as well as its downstream signaling pathways, inducing neuroprotection in different stress cellular models. Based on these premises, we propose the Trk receptor family as potential proteic affinity receptors for TeNT. In vitro, Hc-TeNT binds to a synthetic TrkB-derived peptide and acts similar to an agonist ligand for TrkB, resulting in phosphorylation of the receptor. These properties are weakened by the mutagenesis of three residues of the predicted interaction region in Hc-TeNT. It also competes with Brain-derived neurotrophic factor, a native binder to human TrkB, for the binding to neural membranes, and for uptake in TrkB-positive vesicles. In addition, both molecules are located together in vivo at neuromuscular junctions and in motor neurons. 相似文献
8.
9.
10.
Pungente MD Jubeli E Øpstad CL Al-Kawaz M Barakat N Ibrahim T Abdul Khalique N Raju L Jones R Leopold PL Sliwka HR Partali V 《Molecules (Basel, Switzerland)》2012,17(3):3484-3500
The success of nucleic acid delivery requires the development of safe and efficient delivery vectors that overcome cellular barriers for effective transport. Herein we describe the synthesis of a series of novel, single-chain rigid cationic carotenoid lipids and a study of their preliminary in vitro siRNA delivery effectiveness and cellular toxicity. The efficiency of siRNA delivery by the single-chain lipid series was compared with that of known cationic lipid vectors, 3β-[N-(N',N'-dimethylaminoethane)carbamoyl]-cholesterol (DC-Chol) and 1,2-dimyristoyl-sn-glyceryl-3-phosphoethanolamine (EPC) as positive controls. All cationic lipids (controls and single-chain lipids) were co-formulated into liposomes with the neutral co-lipid, 1,2-dioleolyl-sn-glycerol-3-phosphoethanolamine (DOPE). Cationic lipid-siRNA complexes of varying (+/-) molar charge ratios were formulated for delivery into HR5-CL11 cells. Of the five single-chain carotenoid lipids investigated, lipids 1, 2, 3 and 5 displayed significant knockdown efficiency with HR5-CL11 cells. In addition, lipid 1 exhibited the lowest levels of cytotoxicity with cell viability greater than 80% at all (+/-) molar charge ratios studied. This novel, single-chain rigid carotenoid-based cationic lipid represents a new class of transfection vector with excellent cell tolerance, accompanied with encouraging siRNA delivery efficiency. 相似文献