全文获取类型
收费全文 | 235篇 |
免费 | 2篇 |
专业分类
化学 | 131篇 |
晶体学 | 6篇 |
力学 | 1篇 |
数学 | 6篇 |
物理学 | 93篇 |
出版年
2020年 | 4篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 13篇 |
2012年 | 6篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 5篇 |
2008年 | 8篇 |
2007年 | 2篇 |
2006年 | 13篇 |
2005年 | 16篇 |
2004年 | 14篇 |
2003年 | 12篇 |
2002年 | 9篇 |
2001年 | 3篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1997年 | 5篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 6篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 1篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1966年 | 4篇 |
1965年 | 11篇 |
1963年 | 2篇 |
排序方式: 共有237条查询结果,搜索用时 437 毫秒
101.
102.
Hiroaki Masuzaki Masahiro Hosono Kazuo Nitta 《Applied biochemistry and biotechnology》2017,181(1):65-82
Two novel sugar acid-binding lectins were purified from Haplomitrium mnioides (Lindb.) Schust. using a procedure consisting of ammonium sulfate precipitation, G-50 gel filtration, hydroxyapatite chromatography, and HW-50 gel filtration. We reported their partial physicochemical properties: molecular weight, affinity for carbohydrates and organic acids, pH stability, and dependence of their hemagglutination activity on metal ions. We also determined their N-terminal amino acid sequences. H. mnioides lectins (HMLs) were monomers (one with a molecular weight of approximately 27 kDa, and the other with a molecular weight of approximately 105 kDa) under both nonreducing and reducing conditions. They were named HML27 and HML105, respectively. Both HMLs had an affinity for N-acetylneuraminic acid, d-glucuronic acid, d-glucaric acid, bovine submaxillary mucin, heparin, and organic acids, such as citrate, 2-oxoglutaric acid, and d-2-hydroxyglutarate. Furthermore, HML27 had an affinity for α-d-galacturonic acid, d-malate, l-malate, and pyruvate, while HML105 had an affinity for d-gluconic acid. HML27 and HML105 are novel plant lectins: they have an affinity for sugar acids and organic acids and specifically recognize the carboxyl group, and there is no homology between their N-terminal amino acid sequences and those of the previously described lectins and agglutinins. 相似文献
103.
Parallel phase-shifting digital holography (PPSDH) enables the instantaneous recording of three-dimensional fields. The three-dimensional field can be reconstructed using a computer by numerical scalar wave propagation. In PPSDH, we record a space-division multiplexed hologram that includes the required phase retardation in the spatial distribution of the reference wave and then interpolate the data at blanked pixels for each phase retardation to obtain the complex amplitude distribution of an object wave. The recorded quality of the multiplexed hologram influences the reconstruction quality. In this study, we investigate the effect of the intensity quantization of a multiplexed hologram on the reconstruction quality. We compare the influence of intensity quantization in PPSDH with that in the conventional phase-shifting method. Random noise is also added to the multiplexed hologram. The required intensity quantization level is helpful for selecting a digital image sensor. 相似文献
104.
Quantum motion of particles tunneling a double barrier potential is considered by using stochastic mechanics. Stochastic-mechanical trajectories give us information about complex motion of tunneling particles that is not obtained within the framework of ordinary quantum mechanics. Using such information, we calculate the tunneling times within each of the barriers which depend on the distance between them. It is found that the stochastic-mechanical tunneling time shows better asymptotic behavior than the quantum-mechanical dwell time and presence time. 相似文献
105.
Nobuyuki Kobayashi Shoji Nitta Hitoe Habuchi Takuya Yasui Takashi Itoh Shuichi Nonomura 《Molecular Crystals and Liquid Crystals》2013,570(1):781-786
Abstract C60 molecules were embedded in the pores of a zeolite FSM-16 by using a liquid phase method. The shift of photoluminescence spectra of C60 solid embedded in FSM-16 was discussed using data of ESR, PDS and SAXS. 相似文献
106.
Takashi Itoh Ryo Yasuda Takayuki Go Shoji Nitta Shuichi Nonomura 《Molecular Crystals and Liquid Crystals》2013,570(1):661-666
Abstract The intercalation of O2 in C60 and C70 solids have been studied. In both gas effusion spectra of C60 and C70 powder exposed to O2 at room temperature, two evolution peaks of O2 are found near 80 and 150°C. In both C60 and C70 powder, the peak near 80°C does not depend on a heating ratio and the peak near 150°C shifts to higher temperature with the heating ratio. The activation energy on diffusion of O2 in C60 and C70 solids are ~0.27eV and ~0.46eV, respectively. The number of O2 intercalated in C70 powder is larger than that in C60 powder. Electron spin density of 02-intercalated C60 film is larger than that of C70 film. The effect on the properties of C60 and C70 solids by the intercalation of O2 are discussed. 相似文献
107.
Tomokazu Numano Yoshihiko Kawabata Kazuyuki Mizuhara Toshikatsu Washio Naotaka Nitta Kazuhiro Homma 《Magnetic resonance imaging》2013
The purpose of this study was to develop a new technique for a powerful compact MR elastography (MRE) actuator based on a pneumatic ball-vibrator. This is a compact actuator that generates powerful centrifugal force vibrations via high speed revolutions of an internal ball using compressed air. This equipment is easy to handle due to its simple principles and structure. Vibration frequency and centrifugal force are freely adjustable via air pressure changes (air flow volume), and replacement of the internal ball. In order to achieve MRI compatibility, all parts were constructed from non-ferromagnetic materials. Vibration amplitudes (displacements) were measured optically by a laser displacement sensor. From a bench test of displacement, even though the vibration frequency increased, the amount of displacement did not decrease. An essential step in MRE is the generation of mechanical waves within tissue via an actuator, and MRE sequences are synchronized to several phase offsets of vibration. In this system, the phase offset was detected by a four-channel optical-fiber sensor, and it was used as an MRI trigger signal. In an agarose gel phantom experiment, this actuator was used to make an MR elastogram. This study shows that the use of a ball actuator for MRE is feasible. 相似文献
108.
Non-Abelian global strings are expected to form during the chiral phase transition. They have orientational zero modes in the internal space, associated with the vector-like symmetry SU(N)L+R broken in the presence of strings. The interaction among two parallel non-Abelian global strings is derived for general relative orientational zero modes, giving a non-Abelian generalization of the Magnus force. It is shown that when the orientations of the strings are the same, the repulsive force reaches the maximum, whereas when the relative orientation becomes the maximum, no force exists between the strings. For the Abelian case we find a finite volume correction to the known result. The marginal instability of the previously known Abelian η′ strings is discussed. 相似文献
109.
We show that knots of spin textures can be created in the polar phase of a spin-1 Bose-Einstein condensate, and discuss experimental schemes for their generation and probe, together with their lifetime. 相似文献
110.
Making use of the inelastic scattering function introduced by Ohtsuki, the position dependent stopping power is derived for energetic ions in a channeling condition. We can interprete the Lindhard theory, Esbensen-Golovchenko theory, and Burenkov-Komarov-Kumakhov theory for the channeling stopping power in terms of our method. Our results agree very well with experiment. 相似文献