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排序方式: 共有262条查询结果,搜索用时 31 毫秒
111.
T. Inoue T. Furukawa A. Yoshimi Y. Ichikawa M. Chikamori Y. Ohtomo M. Tsuchiya N. Yoshida H. Shirai M. Uchida K. Suzuki T. Nanao H. Miyatake H. Ueno Y. Matsuo T. Fukuyama K. Asahi 《Hyperfine Interactions》2013,220(1-3):59-63
The present status of an active spin maser which is being developed for an experimental search for 129Xe atomic electric dipole moment (EDM) is presented. In order to realize the long term stability of maser frequency, systematic effects for the spin maser operation were investigated. The correlations in the maser frequency with the solenoid current, the environmental field and the cell temperature were found. With the solenoid current and environmental field being stabilized and the cell temperature lowered, a frequency precision of 7.9 nHz has been achieved for the maser operation. 相似文献
112.
Goto-Inoue N Manabe Y Miyatake S Ogino S Morishita A Hayasaka T Masaki N Setou M Fujii NL 《Analytical and bioanalytical chemistry》2012,403(7):1863-1871
Lipids in skeletal muscle play a fundamental role both in normal muscle metabolism and in disease states. Skeletal muscle lipid accumulation is associated with several chronic metabolic disorders, including obesity, insulin resistance, and type 2 diabetes. However, it is poorly understood whether the lipid composition of skeletal muscle changes by contraction, due to the complexity of lipid molecular species. In this study, we used matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) to investigate changes in skeletal muscle lipid composition induced by contraction. We successfully observed the reduction of diacylglycerol and triacylglycerol, which are generally associated with muscle contraction. Interestingly, we found the accumulation of some saturated and mono-unsaturated fatty acids and poly-unsaturated fatty acids containing phosphatidylcholine in contracted muscles. Moreover, the distributions of several types of lipid were changed by contraction. Our results show that changes in the lipid amount, lipid composition, and energy metabolic activity can be evaluated in each local spot of cells and tissues at the same time using MALDI-IMS. In conclusion, MALDI-IMS is a powerful tool for studying lipid changes associated with contractions. 相似文献
113.
114.
Yuto?Tanaka Nikolay?N.?Nedyalkov Minoru?Obara 《Applied Physics A: Materials Science & Processing》2009,96(1):91-98
We present new results for laser excited semiconductor crystals probed by ultrashort x-ray pulses diffracted by the crystal
lattice. First we discuss acoustical phonons of semiconductors, i.e. indium antimonite and germanium, and then we describe
the temporal evolution of the laser-induced metal–semiconductor phase transition of samarium sulfide. 相似文献
115.
Komeiji Y Ishikawa T Mochizuki Y Yamataka H Nakano T 《Journal of computational chemistry》2009,30(1):40-50
Fragment Molecular Orbital based-Molecular Dynamics (FMO-MD, Komeiji et al., Chem Phys Lett 2003, 372, 342) is an ab initio MD method suitable for large molecular systems. Here, FMO-MD was implemented to conduct full quantum simulations of chemical reactions in explicit solvation. Several FMO-MD simulations were performed for a sphere of water to find a suitable simulation protocol. It was found that annealing of the initial configuration by a classical MD brought the subsequent FMO-MD trajectory to faster stabilization, and also that use of bond constraint in the FMO-MD heating stage effectively reduced the computation time. Then, the blue moon ensemble method (Sprik and Ciccotti, J Chem Phys 1998, 109, 7737) was implemented and was tested by calculating free energy profiles of the Menschutkin reaction (H3N + CH3Cl --> +H3NCH3 + Cl-) in the presence and absence of the solvent water via FMO-MD. The obtained free energy profiles were consistent with the Hammond postulate in that stabilization of the product by the solvent, namely hydration of Cl-, shifted the transition state to the reactant-side. Based on these FMO-MD results, plans for further improvement of the method are discussed. 相似文献
116.
Honami Tamaya Yuto Torii Takumi Ishikawa Prof. Dr. Hideyuki Nakano Dr. Toshifumi Iimori 《Chemphyschem》2019,20(19):2531-2538
We report absorption, fluorescence, and Raman spectroscopy of 7,7,8,8-tetracyanoquinodimethane (TCNQ) in a variety of solvents. The fluorescence quantum yields (QYs) of linear alkane solutions are similar to one another, but QY is shown to acutely decrease in other solvents with increasing polarities. The slope of the solvatochromic plot of absorption maxima is inverted from negative to positive with an increase in solvent polarity. A significant change in the frequency of carbon-carbon double bond stretching modes is not observed in Raman spectra of TCNQ in different solvents. The molar absorption coefficient is determined to calculate the oscillator strength of the absorption band. The radiative decay rate constant calculated from the oscillator strength is approximately ten times larger than that elucidated from the fluorescence lifetime and QY. These spectroscopic parameters reveal that the relaxation occurs from a Franck-Condon excited state to a distinct fluorescence emissive state with a smaller transition dipole moment. 相似文献
117.
Novel optically active hypervalent iodine(V) reagents with planar chiral crown ether backbones were synthesized using the intramolecular Huisgen reaction as a key step and l-methyl lactate as the source of chirality. The relative configurations of these reagents and stabilities of planar chiralities were determined by DFT calculations. These planar chiral reagents were applied to the hydroxylative dearomatization/[4 + 2]-dimerization reactions of phenols to afford bisthymol and biscarvacrol, a natural product, with moderate enantioselectivities. 相似文献
118.
Inside Back Cover: A Bioorthogonal Approach for the Preparation of a Titanium‐Binding Insulin‐like Growth‐Factor‐1 Derivative by Using Tyrosinase (Angew. Chem. Int. Ed. 38/2016)
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119.
S. Kubono N. Ikeda M. Yasue T. Nomura Y. Fuchi H. Kawashima S. Kato H. Orihara T. Shinozuka H. Ohnuma H. Miyatake T. Shimoda 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(3):359-360
The first excited state above the p +19Ne threshold in20Na has been identified at 2.637 MeV (± 15 keV) with Jπ=0+ or 1+ from the20Ne(3He, t)20Na reaction, suggesting this state to be the s-wave resonance in the p +19Ne scattering at stellar energies. 相似文献
120.
Takeshi Nakatani Tomohiro Matsushita Yutaka Miyatake Tomohito Nohno Atsushi Kobayashi Keiki Fukumoto Shunsuke Okamoto Azusa Nakamoto Fumihiko Matsui Ken Hattori Masato Kotsugi Yuji Saitoh Shigemasa Suga Hiroshi Daimon 《Progress in Surface Science》2003,71(5-8):217-239
A stereograph of atomic arrangement was displayed directly on the screen of display-type spherical-mirror analyzer without any computer-aided conversion process for the first time. This stereoscopic photograph enables viewing three-dimensional atomic arrangement. This technique was realized taking advantage of the phenomenon of circular dichroism in photoelectron angular distribution. The azimuthal shifts of forward focusing peaks in a photoelectron angular distribution taken with left and right helicity light in a special arrangement are the same as the parallaxes in a stereo view of atoms. Hence a stereoscopic recognition of three-dimensional atomic arrangement is possible, when the left eye and the right eye respectively view the two images obtained by left and right helicity light simultaneously. 相似文献