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991.
Yongbing Shen Goulven Cosquer Hiroshi Ito David C. Izuogu Alex J. W. Thom Toshiaki Ina Tomoya Uruga Takefumi Yoshida Shinya Takaishi Brian K. Breedlove Zhao‐Yang Li Masahiro Yamashita 《Angewandte Chemie (International ed. in English)》2020,59(6):2399-2406
The first three‐dimensional (3D) conductive single‐ion magnet (SIM), (TTF)2[Co(pdms)2] (TTF=tetrathiafulvalene and H2pdms=1,2‐bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt3]2[M(pdms)2] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms)2]n? and the TTF.+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms)2]n? donor and TTF.+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor–acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF)2[Co(pdms)2] ( 2‐Co ) is an excellent building block for preparing new conductive SIMs. 相似文献
992.
Zahariah Ismail Mohd Suria Affandi Yusoff Khairudin Hashim 《Journal of Dispersion Science and Technology》2013,34(1):72-75
A two-in-one product, a skin whitening lotion enriched with tocotrienols that ultra moisturizes and lightens, was successfully prepared. The basic formulation for this product was prepared by constructing a ternary phase diagram consisting of medium chain triglycerides (MCT), mixed glucose-based emulsifiers, and deionized water at 80°C. The right ratio of these compounds was selected based on liquid crystalline region to produce a stable product. Other palm-based materials were added to the basic formulation. The product was found to be stable for more than 3 months upon storage stability test. The mean droplet size is 10 µm with a monomodal distribution pattern which prevents agglomeration. This decreases Brownian motion, thus prolonging its stability. Long-term acute moisturizing tests showed a significant increase of between 21.2% and 15.4% hydration for 5 and 6 weeks, respectively. The efficacy testing on 20 subjects confirmed a reduction in melanin content, lightening the skin in 4 weeks. 相似文献
993.
L. L. M. Babkov Ya. Baran N. A. Davydova A. Petrashko K. E. Uspenskii 《Journal of Structural Chemistry》2006,47(4):745-753
The crystalline structure of 2-biphenylmethanol has been investigated by the radiographic method at room temperature, and its IR transmission spectra were measured in the 400–4000 cm?1 range. Structural-dynamic models of free molecules of 2-biphenylmethanol, biphenyl and methanol, hydrogen-bonded complexes of 2-biphenylmethanol with methanol and a tetramer of methanol molecules have been built by the density functional method (B3LYP/6-31G*). The structure, the energy, mechanical and electro-optical parameters, the frequency and intensity of normal vibrations in IR spectra of each of the mentioned molecular systems were calculated. The crystalline structure of 2-biphenylmethanol, its features determined by the hydrogen bond formation in the crystal has been found, its structure-forming role and energy were assessed, and IR spectra interpreted on the basis of single crystal X-ray diffraction data, the analysis of measured IR spectra, and results of molecular modeling. 相似文献
994.
In this work, investigation of the spectroscopic parameters of the luminescence of Yb3+ ions in single crystalline films of Lu3Al5O12 and Y3Al5O12 garnets was performed using the synchrotron radiation excitation with the energy in the range of Yb3+ charge transitions (CT), exciton range and the onset of interband transitions of these garnets. The basic spectroscopic parameters of the Yb3+ CT luminescence in LuAG and YAG hosts were determined and summarized with taking into account the differences in the band gap structure of these garnets. 相似文献
995.
996.
R. Watanabe T. Iyoda T. Yamada H. Yoshida 《Journal of Thermal Analysis and Calorimetry》2006,85(3):713-717
Phase transition process of PEOm-b-PMA(Az)n was investigated
by the simultaneous DSC-XRD measurement using the synchrotron radiation facility.
Four endothermic DSC peaks were observed during heating process. These DSC
peaks were assigned to the melting of PEO, the transition from SmX, which
is a mixture of super-cooled SmC and crystal, to SmC, from SmC to SmA, and
from SmA to isotropic liquid state as determined by XRD profiles. In SmC phase,
the liner expansion coefficient calculated from the spacing variation of the
smectic layer distance was larger than that of the other phases. This result
reflected the fact azobenzene moieties in the long-side chains of PMA(Az)n
forming the smectic layers and then they were tilted and stood up during the
heating process. 相似文献
997.
P.?Cluzeau F.?Bougrioua G.?Joly L.?LejcekEmail author H.T.?Nguyen 《Czechoslovak Journal of Physics》2005,55(6):719-737
A simplified model of an inclusion represented by (+1)-wedge disclination and two accompanying (– 1/2)-wedge disclinations on the surface of inclusion in smectic C free standing films is used to describe the elastic interaction of inclusions. The orientation of the axis connecting positions of all three disclinations relatively to the director orientation at far distances due to elastic anisotropy is investigated. The configuration with the lowest director perturbations and the lowest anisotropy elastic energy is such that the axis connecting disclinations is parallel to the distant director orientation. The interaction between inclusions at far distances is quadrupolar. The chaining of inclusions is approximately described considering their repulsion due to molecular anchoring at inclusion surfaces. 相似文献
998.
在晶场理论和分子场理论的基础上,通过模拟Taiki Ueda和M.S.Kim等人测量的磁化率实验结果,得到了稀土化合物CeRhGe和CeRhSn的晶场分裂,分析了晶场效应对化合物磁性质的影响.计算结果表明,Ce3 晶场分裂得到了双基态,两种化合物的第一激发能和总激发能分别是723 K、610 K和970 K、1130 K,与实验获得了较好的吻合. 相似文献
999.
The non-isothermal crystallization behavior of poly(trimethylene terephthalate) (PTT) and its blends with a liquid crystalline
polymer, namely Vectra A950 (VA), was studied by differential scanning calorimetry. The values of the half-time of crystallization,
t
0.5 and the parameter F(T) in the combined Avrami and Ozawa equation indicated that VA can enhance the PTT crystallization rate by acting as a nucleating
agent. The crystallization activation energy of the PTT phase increased with increasing VA content. The blends were immiscible,
as can be inferred from their morphology. Thermogravimetric analysis of the blends revealed improved thermal stability by
the incorporation of VA. 相似文献
1000.
Kenji Masuda Hironori Kaji Fumitaka Horii 《Journal of Polymer Science.Polymer Physics》2000,38(1):1-9
The chain conformation and hydrogen bonding in the crystalline and noncrystalline regions have been characterized for atactic poly(vinyl alcohol) (PVA) films prepared under different conditions by CP/MAS 13C NMR analyses developed recently. The CH resonance lines of the crystalline and noncrystalline components split in different ways, depending significantly on casting solvents and annealing. These lines are found to be successfully resolved into 3–7 constituent lines by the least‐squares curve fitting. In this analysis, nine lines with different chemical shifts are prepared as elementary lines for the curve fitting by assuming the upfield shifts due to the γ‐gauche effect and the downfield shifts due to the formation of the intramolecular hydrogen bonds. The integrated intensities of the constituent lines thus obtained are also interpreted in terms of statistical calculations, assuming the random distribution of the trans and gauche conformations along PVA chains and the statistical distribution of the intramolecular and intermolecular hydrogen bonds between appropriate adjacent OH groups. On the basis of probabilities ft and fa for the trans conformation and the intramolecular hydrogen bond obtained through these analyses, the effects of casting solvents and annealing are discussed for both crystalline and noncrystalline components. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1–9, 2000 相似文献