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111.
Manju Rajeswaran Thomas N. Blanton Ching W. Tang William C. Lenhart Steven C. Switalski David J. Giesen Brian J. Antalek Thomas D. Pawlik Denis Y. Kondakov Nicholas Zumbulyadis Ralph H. Young 《Polyhedron》2009
The interest in organic materials for use in organic light-emitting diodes (OLEDs) began with the pioneering report of efficient green electroluminescence from Alq3, tris(quinolin-8-olato)aluminum(III), by Tang and Van Slyke [C.W. Tang, S.A. Van Slyke, Appl. Phys. Lett. 51 (1987) 913]. After more than 20 years of intense research and development in OLEDs, Alq3 continues to be a widely used electroluminescent material in OLED technology. Alq3 is used in the electron-transport and/or electron-injecting layer in multilayer device structures and also as an effective host material for various dyes. Much is known about the properties of this metal chelate complex, yet much remains unknown despite numerous studies. In recent years, five crystalline phases (α, β, γ, δ, and ε) of Alq3 have been identified. In the present report, a combined structural, thermal, and spectroscopic (Raman, fluorescence, and nuclear magnetic resonance) analysis of different crystalline phases of Alq3 is presented. 相似文献
112.
113.
We report results of molecular dynamics investigations into neutral impurity diffusing within an amorphous solid as a function
of the size of the diffusant and density of the host amorphous matrix. We find that self diffusivity exhibits an anomalous
maximum as a function of the size of the impurity species. An analysis of properties of the impurity atom with maximum diffusivity
shows that it is associated with lower mean square force, reduced backscattering of velocity autocorrelation function, near-exponential
decay of the intermediate scattering function (as compared to stretched-exponential decay for other sizes of the impurity
species) and lower activation energy. These results demonstrate the existence of size-dependent diffusivity maximum in disordered
solids. Further, we show that the diffusivity maximum is observed at lower impurity diameters with increase in density. This
is explained in terms of the Levitation parameter and the void structure of the amorphous solid. We demonstrate that these
results imply contrasting dependence of self diffusivity (D) on the density of the amorphous matrix, ρ. D increases with ρ for small sizes of the impurity but shows an increase followed by a decrease for intermediate sizes of the impurity atom.
For large sizes of the impurity atom, D decreases with increase in ρ. These contrasting dependence arises naturally from the existence of Levitation Effect.
相似文献
114.
We characterize all the central topological groupsG for which the centreZ(L
1(G)) of the group algebra admits a finite universal Korovkin set. It is proved thatZ(L
1(G)) has a finite universal Korovkin set iffĜ is a finite dimensional, separable metric space. This is equivalent to the fact thatG is separable, metrizable andG/K has finite torsion free rank, whereK is a compact open normal subgroup of certain direct summand ofG. 相似文献
115.
116.
To study the effect of nanofiller particle TiO2 on sodium (Na+) – ion conducting solid polymer electrolyte (SPE) film: [80PEO:20NaPF6] and nanocomposite polymer electrolyte (NCPE): [80PEO:20NaPF6] + xTiO2, where x = 1–9 wt. (%) have been prepared. SPE film composition: [80PEO:20NaPF6] selects as Ist-phase host and nano-sized (<100 nm) filler materials TiO2 as IInd-phase dispersoid. Both SPE and NCPE films have been prepared by the hot-press technique. Filler particle-dependent conductivity study reveals the NCPE system: [80PEO:20NaPF6] + 8TiO2 as the highest conducting composition with σrt − 3.53 × 10−6 S cm−1, which is approximately one order of magnitude higher than the SPE optimum conducting composition (OCC) (σrt) ≈ 7.78 × 10−7 S cm−1. Ion transport properties for both SPE and NCPE system have been evaluated in terms of ionic conductivity (σ) and total ionic (tion)/cationic (t+) transference numbers using combined AC/DC techniques in order to evaluate its usefulness in all-solid-state battery applications. Structural/thermal properties have been characterized using X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques. A cyclic voltammetry (CV) study has been performed in SPE and NCPE OCC film to evaluate the electrochemical performance for battery application. 相似文献
117.
Nan-Gang Ma Eric M. Y. Yau Manju Aravind Dickon H. L. Ng † Sammy L. I. Chan 《哲学杂志》2013,93(35):3771-3784
A Mg–Mg2Ni nano-eutectic and MgO-reinforced Mg-based metal matrix composite (Mg-MMC) was synthesized by in-situ reactions. When a Mg-rich sample containing 20?wt%?NiO is sintered at 420°C, MgO, Ni and Mg2Ni are formed in the Mg matrix. When a sample molten at 550°C is furnace-cooled to room temperature, a lamellar two-phase Mg–Mg2Ni eutectic is formed, with the Mg2Ni lamella about 1.5?µm thick. Proeutectic Mg together with the MgO formed in situ act as heterogeneous nuclei for the growth of the Mg–Mg2Ni eutectic. Quenching the molten sample to room temperature results in a lamellar two-phase eutectic containing Mg2Ni nanofibres. In the eutectic grown at the Mg grain, the Mg2Ni nanofibres with a diameter of about 25?nm are bent, whereas in the eutectic grown at the MgO grain, the Mg2Ni nanofibres with a diameter of about 30?nm are long and straight, while the Mg phase of this eutectic is oxygen enriched. The differences in morphologies between the two Mg–Mg2Ni eutectics are ascribed to the growth rates of Mg and Mg2Ni, which differ in the eutectic grown at the Mg grain, but remain similar when growth takes place at the MgO grain. 相似文献
118.
In this paper, the eight channels dense wavelength division multiplexing (DWDM) optical communication system has been simulated, and power penalty introduced due to neighboring channels required to compensate the crosstalk has been calculated. It has been observed that the intermediate channels are more affected as compared to the boundary channels and more power is required to compensate the loss of information due to crosstalk. 相似文献
119.
A highly efficient and general method based on transmetalation with an organozinc reagent is developed for selective preparation of homo- and heteroleptic meridional tris-cyclometalated iridium complexes. The molecular structure of mer-Ir(1-piq)2(ppy) (2) has been determined by a single-crystal X-ray diffraction analysis. The emission properties of a series of meridional complexes are reported. 相似文献
120.
V. Arun G. P. Preetha S. Manju A. R. Biju K. K. M. Yusuff 《Journal of chemical crystallography》2011,41(7):1013-1017