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61.
Hiroshi Oki Ichiro Oura Tatsuhito Nakamura Kenichi Ogata Shin-ichi Fukuzawa 《Tetrahedron: Asymmetry》2009,20(18):2185-2191
A series of diphosphine ClickFerrophos ligands (CF), based on a triazoleferrocene backbone, was synthesized in a four-step sequence via click chemistry methodology. In addition to the four previously synthesized ligands CF1, CF4, CF7 and CF10, six novel CF ligands CF2–3 and CF5–8 were prepared. Hydrogenation reactions of alkenes and ketones were significantly improved upon by using CF ligands as rhodium- or ruthenium-complexes in which the % ee values can be optimized by choosing the appropriate CF ligand depending on the substrate. 相似文献
62.
Isao Ohta Ichiro Hagino Takenori Kaneko 《International Journal of Infrared and Millimeter Waves》1989,10(6):729-735
Two different types of 5/2-wavelength rat-race-type directional couplers with a remarkably increased power-split ratio for a realizable ring-impedance, in particular which are useful for millimeter-wave circuits suffering from the severe restriction on the usable impedance range, are described. Experimental corroboration is provided in the microwave region (at 8 GHz). 相似文献
63.
Photoluminescence spectra of thenardite Na2SO4 activated with rare-earth ions, Ce, Sm, Tb, Dy and Tm
Five Na2SO4:RE3+ phosphors activated with rare-earth (RE) ions (RE3+=Ce3+, Sm3+, Tb3+, Dy3+ and Tm3+) were synthesized by heating natural thenardite Na2SO4 from Ai-Ding Salt Lake, Xinjiang, China with small amounts of rare-earth fluorides, CeF3, SmF3, TbF3, DyF3 and TmF3, at 920 °C in air. The photoluminescence (PL) and optical excitation spectra of the obtained phosphors were measured at 300 and 10 K. In the PL spectrum of Na2SO4:Ce3+ at 300 K, two overlapping bands with peaks at 335 and 356 nm due to Ce3+ were first observed. Narrow bands observed in PL and excitation spectra of Na2SO4:RE3+ (RE3+=Sm3+, Tb3+, Dy3+ and Tm3+) phosphors were well identified with the electronic transitions within the 4fn (n=5, 8, 9 and 12) configurations of RE3+. The existence of excitation bands with high luminescence efficiency at wavelengths shorter than 230 nm is characteristic of Na2SO4:RE3+ (RE3+=Sm3+, Tb3+, Dy3+ and Tm3+) phosphors. The obtained results suggest that these phosphors are unfavorable as the phosphor for usual fluorescence tubes, i.e., mercury discharge tubes, but may be favorable as the phosphor for UV-LED fluorescent tubes and as cathodoluminescence, X-ray luminescence and thermoluminescence phosphors. 相似文献
64.
Abstract
We have been interested in behaviors of suspended particles in a volatile droplet placed on a smooth substrate. It is known that the particles gather and deposit in the vicinity of the macroscopic contact line of the droplet, which is generally called ‘coffee stain problem’. A convective flow induced by non-uniform evaporation through the interface brings suspended particles toward the pinned contact line in the drying droplet, which forms a ring stain. We have focused on the dynamics of the droplet with/without suspended particles spreading on the solid substrate and on the behaviors of particles in the evaporating droplet. Spreading process of the droplet is significantly affected by the suspended particles. We indicate flow patterns in the droplet, in which the flow exhibits a modal structure with a mode number in the azimuthal direction, and indicate particles depositions after the dryout of the droplet. Three-dimensional particle tracking velocimetry is applied to reconstruct such unique flow patterns in the spreading process of the droplet. Resultant patterns of the particles depositing on the substrate are introduced. 相似文献65.
Yasuaki Ueki Takashi Torigoe Hirofumi Ono Ryo Yoshiie Joseph H. Kihedu Ichiro Naruse 《Proceedings of the Combustion Institute》2011,33(2):1795-1800
Gasification technology is recognized as one of the possibilities for utilizing biomass effectively. This study focused on woody biomass gasification fundamentals, using a bench-scale packed-bed reactor. In this experiment, pellets of black pine were gasified, using air as the oxidizing agent. Gasification tests were carried out under both updraft and downdraft conditions. Temperature distributions and compositions of syngas inside the gasifier were continuously monitored during gasification experiments at several ports on the wall of the reactor. The syngas at the exit of the gasifier was also sampled to estimate the amount of tar. Lower heating values of the syngas under updraft and downdraft conditions were 4.8 and 3.8 MJ/m3N, respectively. It was easier to control the height of the packed bed under the downdraft condition than under the updraft condition. Under the updraft condition, a bridging phenomenon occurred. Tar generation under the downdraft condition was lower than that under the updraft condition. This is because tar passes through a partial combustion zone or higher temperature zone in the downdraft gasifier. 相似文献
66.
Toshinori Taishi Hideaki Ise Yu Murao Takayuki Osawa Masashi Suezawa Yuki Tokumoto Yutaka Ohno Keigo Hoshikawa Ichiro Yonenaga 《Journal of Crystal Growth》2010,312(19):2783-2787
Oxygen-containing germanium (Ge) single crystals with low density of grown-in dislocations were grown by the Czochralski (CZ) technique from a Ge melt, both with and without a covering by boron oxide (B2O3) liquid. Interstitially dissolved oxygen concentrations in the crystals were determined by the absorption peak at 855 cm−1 in the infrared absorption spectra at room temperature. It was found that oxygen concentration in a Ge crystal grown from melt partially or fully covered with B2O3 liquid was about 1016 cm−3 and was almost the same as that in a Ge crystal grown without B2O3. Oxygen concentration in a Ge crystal was enhanced to be greater than 1017 cm−3 by growing a crystal from a melt fully covered with B2O3; with the addition of germanium oxide powder, the maximum oxygen concentration achieved was 5.5×1017 cm−3. The effective segregation coefficients of oxygen in the present Ge crystal growth were roughly estimated to be between 1.0 and 1.4. 相似文献
67.
Anne Davaille Angela Limare Floriane Touitou Ichiro Kumagai Judith Vatteville 《Experiments in fluids》2011,50(2):285-300
We present an experimental study of the dynamics of a plume generated from a small heat source in a high Prandtl number fluid
with a strongly temperature-dependent viscosity. The velocity field was determined with particle image velocimetry, while
the temperature field was measured using differential interferometry and thermochromic liquid crystals. The combination of
these different techniques run simultaneously allows us to identify the different stages of plume development, and to compare
the positions of key-features of the velocity field (centers of rotation, maximum vorticity locations, stagnation points)
respective to the plume thermal anomaly, for Prandtl numbers greater than 103. We further show that the thermal structure of the plume stem is well predicted by the constant viscosity model of Batchelor
(Q J R Met Soc 80: 339–358, 1954) for viscosity ratios up to 50. 相似文献
68.
Ichiro Nishizaki Hideki Katagiri Tomohiro Hayashida 《Central European Journal of Operations Research》2010,18(3):383-396
A multiattribute utility function can be represented by a function of single-attribute utility functions if the decision maker’s
preference satisfies additive independence or mutually utility independence. Additive independence is a preference condition
stronger than mutually utility independence, and the multiattribute utility function is in the additive form if the former
condition is satisfied, otherwise it is in the multiplicative form. In this paper, we propose a method for sensitivity analysis
of multiattribute utility functions in multiplicative form, taking into account the imprecision of the decision maker’s judgment
in the procedures for determining scaling constants (attribute weights). 相似文献
69.
Ichiro Tsunenari Jyoji Yamate Masae Iwaki Mitsuru Kuwamura Takao Kotani Sadashige Sakuma 《Microscopy and microanalysis》2003,9(6):532-541
Angiogenesis, a biologic process whereby endothelial cells divide and migrate to form new blood vessels, is a key step in tumor growth, invasion, and metastasis. In the present study, we investigated the differences in angioarchitecture between two different tumors induced by cloned cell lines (MT-8 and MT-9), derived from a transplantable rat malignant fibrous histiocytoma, by scanning electron microscopy of vascular corrosion casts. During a 3-week observation period after implantation, the growth of MT-8 tumors appeared to be faster than that of MT-9 tumors. Histologically, MT-8 tumors were of the uniformly undifferentiated sarcoma type arranged in characteristic organoid structures, and MT-9 tumors showed a storiform growth pattern. In MT-8 tumors, neovascularization occurred by sprouting at postimplantation (PI) week 1, and the newly formed capillaries gradually became more tortuous. In MT-9 tumors, at PI week 1, the corrosion casts of newly formed capillaries mainly showed a wavy course but no finger-like outgrowths of capillaries were seen. At PI weeks 2 and 3, the sprouting was seen specifically in MT-9 tumors, forming basket-like structures and glomeruloid structures of capillaries. These results indicate that angiogenesis or angioarchitecture of MT-8 tumors is different from that of MT-9 tumors, depending on the differences in their tumor histology and by the features like absence or presence of basket-like structures and glomeruloid structures of capillaries. 相似文献
70.
Michihito Ueda Masahiro Ueda Hiroaki Takagi Masayuki J. Sato Toshio Yanagida Ichiro Yamashita Kentaro Setsune 《Physica A》2008,387(16-17):4475-4481
“End of Moore’s Law” has recently become a topic. Keeping the signal-to-noise ratio (SNR) at the same level in the future will surely increase the energy density of smaller-sized transistors. Lowering the operating voltage will prevent this, but the SNR would inevitably degrade. Meanwhile, biological systems such as cells and brains possess robustness against noise in their information processing in spite of the strong influence of stochastic thermal noise. Inspired by the information processing of organisms, we propose a stochastic computing model to acquire information from noisy signals. Our model is based on vector matching, in which the similarities between the input vector carrying external noisy signals and the reference vectors prepared in advance as memorized templates are evaluated in a stochastic manner. This model exhibited robustness against the noise strength and its performance was improved by addition of noise with an appropriate strength, which is similar to a phenomenon observed in stochastic resonance. Because the stochastic vector matching we propose here has robustness against noise, it is a candidate for noisy information processing that is driven by stochastically-operating devices with low energy consumption in future. Moreover, the stochastic vector matching may be applied to memory-based information processing like that of the brain. 相似文献