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121.
122.
Kaho Tanaka Naohiko Akasaka Tomoyuki Kosai Shunya Honda Yuya Ushijima Shintaro Ishida Takeaki Iwamoto 《Molecules (Basel, Switzerland)》2021,26(6)
π-Electron systems of silicon have attracted attention because of their narrow HOMO-LUMO gap and high reactivity, but the structural diversity remains limited. Herein, new dialkylboryl-substituted disilenes were synthesized by the selective desilylation-borylation of the corresponding trimethylsilyl-substituted disilenes. The dialkylboryl-substituted disilenes were fully characterized by a combination of NMR spectroscopy, MS spectrometry, single-crystal X-ray diffraction analysis, and theoretical calculations. The longest-wavelength absorption bands of boryldisilenes were bathochromically shifted compared to the corresponding silyl-substituted disilenes, indicating a substantial conjugation between π(Si=Si) and vacant 2p(B) orbitals. In the presence of 4-(dimethylamino)pyridine (DMAP), the dialkylboryl groups in the boryl-substituted disilenes were easily converted to trimethylsilyl groups, suggesting the dialkylboryl-substituted disilenes in the presence of a base serve as the surrogates of disilenyl anions (disilenides). 相似文献
123.
124.
Inside Back Cover: Electrical Network of Single‐Crystalline Metal Oxide Nanoclusters Wired by π‐Molecules (Angew. Chem. Int. Ed. 42/2014)
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125.
Fusao Kawamura Yohji Seki Kaoru Iwamoto Hiroshi Kawamura 《International Journal of Heat and Fluid Flow》2007,28(6):1291-1301
Direct numerical simulation (DNS) of heat transfer in a channel flow obstructed by rectangular prisms has been performed for Reτ = 80–20, where Reτ is based on the friction velocity, the channel half width and the kinematic viscosity. The molecular Prandtl number is set to be 0.71. The flow remains unsteady down to Reτ = 40 owing to the disturbance induced by the prism. For Reτ = 30 and 20, the flow results in a steady laminar flow. In the vicinity of the prism, the three-dimensional complex vortices are generated and heat transfer is enhanced. The Reynolds number effect on the time-averaged vortex structure and the local Nusselt number are investigated. The mechanism of the heat transfer enhancement is discussed. In addition, the mean flow parameters such as the friction factor and the Nusselt number are examined in comparison with existing DNS and experimental data. 相似文献
126.
Munetoshi Seki Masateru Mikami Fujiyuki Iwamoto Yosuke Ono Takamasa Osone Hitoshi Tabata 《Journal of Crystal Growth》2010,312(15):2273-2278
Epitaxial thin films of TmFeCuO4 with a two-dimensional triangular lattice structure were successfully grown on yttria-stabilized-zirconia substrates by pulsed laser deposition and ex situ annealing in air. The films as-deposited below 500 °C showed no TmFeCuO4 phase and the subsequent annealing resulted in the decomposition of film components. On the other hand, as-grown films deposited at 800 °C showed an amorphous nature. Thermal annealing converted the amorphous films into highly (0 0 1)-oriented epitaxial films. The results of scanning electron microscopic analysis suggest that the crystal growth process during thermal annealing is dominated by the regrowth of non-uniformly shaped islands to the distinct uniform islands of hexagonal base. 相似文献
127.
Shigeo Hayakawa Shinya Matsumoto Mami Hashimoto Kenichi Iwamoto Hirofumi Nagao Michisato Toyoda Yasushi Shigeri Michiko Tajiri Yoshinao Wada 《Journal of the American Society for Mass Spectrometry》2010,21(9):1482-1489
Post-translational modifications (PTMs) of proteins are important in the activation, localization, and regulation of protein
function in vivo. The usefulness of electron capture dissociation (ECD) and electron-transfer dissociation (ETD) in tandem
mass spectrometry (MS/MS) using low-energy (LE) trap type mass spectrometer is associated with no loss of a labile PTM group
regarding peptide and protein sequencing. The experimental results of high-energy (HE) collision induced dissociation (CID)
using the Xe and Cs targets and LE-ETD were compared for doubly-phosphorylated peptides TGFLT(p)EY(p)VATR (1). Although HE-CID using the Xe target did not provide information on the amino acid sequence, HE-CID using the Cs target
provided all the z-type ions without loss of the phosphate groups as a result of HE-ETD process, while LE-ETD using fluoranthene
anion gave only z-type ions from z5 to z11. The difference in the results of HE-CID between the Xe and Cs targets demonstrated that HE-ETD process with the Cs target
took place much more dominantly than collisional activation. The difference between HE-ETD using Cs targets and LE-ETD using
the anion demonstrated that mass discrimination was much weaker in the high-energy process. HE-ETD was also applied to three
other phosphopeptides YGGMHRQEX(p)VDC (2: X = S, 3: X = T, 4: X = Y). The HE-CID spectra of the doubly-protonated phosphopeptides
(= [M + 2H]2+) of 2, 3, and 4 using the Cs target showed a very similar feature that the c-type ions from c7 to c11 and the z-type ions from z7 to z11 were formed via N-Cα bond cleavage without a loss of the phosphate group. 相似文献
128.
129.
We study the general energy and shape of the two-dimensional solid monolayer domains with the dipole-dipole interactions. Compared with the domain energy without tilted dipole moments [M. Iwamoto and Z. C. Ou-Yang, Phys. Rev. Lett. 93, 206101 (2004)], the general dipolar energy is not only shape and size but also boundary orientation dependent. The general shape equation derived by this energy using variational approach predicts a circular solution and an equilibrium shape grown from this circle. In particular, the latter is composed of two branches: a translation-induced growth of all odd harmonic modes and a pressure-induced cooperative deformation by all even harmonic modes. The good qualitative agreement between our prediction and the experimental observations shows the validity of the present theory. 相似文献
130.
Electrostatic phenomena occurring at the interface between metal/organic and organic/organic materials are discussed from the viewpoint of dielectrics physics. Focusing on two important origins of surface polarization phenomena, orientational ordering of polar molecules and displacement of excess charges at the interface, surface polarization phenomena of organic thin films are discussed. To define the orientational order of polar molecules, orientational order parameters are introduced, and surface polarization due to the alignment of dipoles is expressed. The generation of Maxwell displacement current (MDC) and optical second harmonic generation (SHG) that are specific for surface organic monomolecular films are discussed, and some experimental evidence are shown. As an extension of the concept of surface Fermi level introduced to discuss the electrostatic phenomena due to electron transfer at the interface between metal-organic insulators, the surface Fermi level is extended to the discussion on the electrostatic phenomena of organic semiconductor materials on metals. In this paper, some experimental evidence of surface polarization originating from polar molecules and displacement of excess charges are shown. After that, with consideration of these surface phenomena, single electron tunneling of organic films are briefly discussed in association with surface polarization phenomena. 相似文献