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961.
962.
963.
Tada A Geng Y Nakamura M Wei Q Hashimoto K Tajima K 《Physical chemistry chemical physics : PCCP》2012,14(11):3713-3724
This feature article focuses on the relationship between the interfacial structures constructed by molecular self-organization and the properties of organic photovoltaic devices. The use of self-assembled monolayers (SAMs) is reviewed for metal and metal oxide/organic interfaces, while surface-segregated monolayers (SSMs) are introduced as a new method for the modification of organic/organic interfaces. Research up to now has clearly demonstrated the effectiveness of the control of energy levels and other properties at the interfaces to enhance photovoltaic performance. The possibility of more precise control of the interfacial structures is also discussed. 相似文献
964.
Quanling Yang Shuji Fujisawa Tsuguyuki Saito Akira Isogai 《Cellulose (London, England)》2012,19(3):695-703
Mechanical, thermal and oxygen barrier properties of regenerated cellulose films prepared from aqueous cellulose/alkali/urea
solutions can be markedly improved by controlling the drying conditions of the films. By pre-pressing followed by vacuum drying
under compression, the tensile strength, Young’s modulus, coefficient of thermal expansion and oxygen permeability of the
dried films reached 263 MPa, 7.3 GPa, 10.3 ppm K−1 and 0.0007 ml μm m−2 day−1 kPa−1, respectively. Thus, films produced in this way show the highest performance of regenerated cellulose films with no orientation
of cellulose chains reported to date. These improved properties are accompanied by a clear increase in cellulose II crystallinity
from 50 to 62% during pre-pressing/press-vacuum drying process. At the same time, the film density increased from 1.45 to
1.57 g cm−3, and the moisture content under equilibrium conditions decreased from 14.1 to 9.8%. Hence, the aqueous alkali/urea solvent
system has potential applications in producing new and environmentally friendly cellulose films with high performances through
control of the drying conditions. 相似文献
965.
Daisuke Suzuki Tomoyo Yamagata Koji Horigome Kiyoshi Shibata Akira Tsuchida Tsuneo Okubo 《Colloid and polymer science》2012,290(2):107-117
Influence of the gel size on the morphology, phase diagram, and reflection spectroscopy of the colloidal crystals of thermo-sensitive
gel spheres, poly (N-isopropylacrylamide) (pNIPAm), was discussed by adding the data of two gel samples of pNIPAm(400–5) and pNIPAm(600–5) of
412 nm (at 25 °C) and 220 nm (at 45 °C) and of 517 nm (at 20 °C) and 294 nm (at 45 °C), respectively. Colloidal single crystals
formed, but not so large compared with the giant crystals of small pNIPAm gels reported previously. The suspensions even with
ion-exchange resins were turbid and hard to observe the single crystals clearly with the naked eyes as gel size increased.
The critical concentration of melting decreased sharply as the suspensions were deionized with coexistence of the mixtures
of cation- and anion-exchange resins. The critical concentration increased as the gel size increased and/or dispersion temperature
increased. Density of the gel spheres increased as their size increased. These results demonstrated that the colloidal crystallization
takes place by the extended electrical double layers formed around the gel spheres in addition of the excluded volume effect of the gels. Contribution of the electrical double layers on the crystallization increased sharply as temperature increased
and gel concentration decreased, respectively. The contribution also increased slightly as sphere size increased, when comparison
was made at the same gel concentration in wt.%. The present work clarified that the colloidal interfaces, which are inevitable
for the formation of the electrical double layers, are formed between the water phase and gel spheres, though the gel spheres
contain a lot of water molecules at the inner sphere region. 相似文献
966.
Minami H Mizuta Y Kimura A 《Langmuir : the ACS journal of surfaces and colloids》2012,28(5):2523-2528
The phase-transfer behavior of poly(acrylic acid) (PAA) particles from the hydrophobic ionic liquid N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)amide phase to the water phase in the particle state, which we reported previously, was examined in more detail. PAA particles were prepared in the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide ([Bmim][TFSA]) and the organic solvent chloroform and were extracted. The transfer of PAA particles to water in the particle state was also observed in [Bmim][TFSA] systems. In contrast, the transfer phenomenon was not observed in the chloroform system. It was clarified that water/oil interfacial tension γ(wo) is an important parameter in the extraction of PAA in the particle state from the viewpoint of free energy. When the cationic surfactant tetradecyltrimethylammonium bromide, aqueous solution was used as the extraction medium, the PAA particles were extracted in the particle state from chloroform to water, in which γ(wo) became as low as that of the ionic liquid. This suggests that the phase-transfer phenomenon of PAA particles in the particle state was induced by the ionic liquid's unique property of low interfacial tension with water despite its high hydrophobic character. 相似文献
967.
Keigo?SuzukiEmail author Nobuhiko?Tanaka Akira?Ando Hiroshi?Takagi 《Journal of nanoparticle research》2012,14(5):863
Size-tuned copper oxide nanoparticles with sizes of 9, 12, and 15 nm were fabricated by laser ablation and on-line size selection
using a differential mobility analyzer at a gas pressure of 666 Pa. The dependence of the particle properties on the in situ
annealing temperatures and selection sizes was investigated. The crystalline phases of the nanoparticles fabricated at temperatures
below 973 K were assigned to monoclinic cupric oxide (CuO) which converted into cubic cuprous oxide (Cu2O) when the annealing temperature was above 1,173 K. This indicates that the crystalline phases can be easily controlled by
changing the annealing temperature. TEM images confirmed that well-crystallized and well-dispersed CuO and Cu2O nanoparticles with narrow size distributions were obtained using this method. This fabrication process is useful and promising
for the future investigation of the intrinsic size-dependent properties of CuO and Cu2O. 相似文献
968.
969.
Akihiro Fukabori Valery Chani Kei Kamada Akira Yoshikawa 《Journal of Crystal Growth》2012,352(1):124-128
In this report, growth of Yb-doped sesqui-oxide crystals of Y2O3, Sc2O3, and Lu2O3 by the micro-pulling-down technique and their scintillation performance are discussed. Growth of these crystals is difficult mostly as a result of their extremely high melting point of around 2400 °C. Nevertheless, appropriate design of the thermal zone and careful control of the growth parameters allowed fabrication of these crystals of reasonable quality. Based on the results of measurements of emission spectra under α-ray excitation and pulse height spectra under α-ray and γ-ray excitations, scintillation characteristics of above crystals including emission wavelength and light yields under α-ray and γ-ray excitations were examined. Additionally, decay kinetics of these materials under α-ray excitation were evaluated. 相似文献
970.
Akira Ishida Yuichi Sasaki Ginga Akimoto Taikan Suehara Toshio Namba Shoji Asai Tomio Kobayashi Haruo Saito Mitsuhiro Yoshida Kenichi Tanaka Akira Yamamoto 《Hyperfine Interactions》2012,212(1-3):133-140
Positronium is an ideal system for the research of the quantum electrodynamics (QED) in bound state. The hyperfine splitting (HFS) of positronium, ΔHFS, gives a good test of the bound state calculations and probes new physics beyond the Standard Model. A new method of QED calculations has revealed the discrepancy by 15 ppm (3.9σ) of ΔHFS between the QED prediction and the experimental average. There would be possibility of new physics or common systematic uncertainties in the previous all experiments. We describe a new experiment to reduce possible systematic uncertainties and will provide an independent check of the discrepancy. We are now taking data and the current result of ΔHFS?=?203.395 1 ±0.002 4 (stat., 12 ppm) ±0.001 9 (sys., 9.5 ppm) GHz has been obtained so far. A measurement with a precision of O(ppm) is expected within a year. 相似文献