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1.
研究了无应力作用条件下,均匀、各向同性、圆柱形微极结构弹性板中波的传播.导出了对称和斜对称模式下波传播的特征方程.对短波这一极端情况,无应力圆板中对称和斜对称模态波的特征方程退化为Pmyle曲表面波频率方程.并得到薄板的计算结果.给出了位移和微转动分量,并绘制了相应图形.给出了若干特殊情况的研究结果及对称和斜对称模态特征方程的图示.  相似文献   
2.
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed.  相似文献   
3.
Thermal decomposition of transition metal malonates, MCH2C2O4?xH2O and transition metal succinates, M(CH2)2C2O4?xH2O (M=Mn, Fe, Co, Ni, Cu, Zn) has been studied employing TG, DTG, DTA, XRD, SEM, IR and Mössbauer spectroscopic techniques. After dehydration, the anhydrous metal malonates and succinates decompose directly to their respective metal oxides in the temperature ranges 310–400 and 400–525°C, respectively. The oxides obtained have been found to be nanosized. The thermal stability of succinates have been found to be higher than that of the respective malonates.  相似文献   
4.
Thermal decomposition of ammonium tris (malonato) ferrate (III) tetrahydrate, i. e. (NH4)3[Fe(CH2C2O4)3]·4H2O has been studied up to 973 K in static air atmosphere employing Mössbauer and infrared spectroscopies, and non-isothermal techniques (TG, DTG, DTA). The anhydrous complex decomposes into an iron (II) intermediate at 453 K. The iron (II) species on further heating is reoxidized to -Fe2O3 as the final thermolysis product. An increase in particle size of -Fe2O3 with increasing decomposition temperature has been observed. The results are compared with the analogous oxalate complex.  相似文献   
5.
Thermal decomposition of some hydroxy iron(III) carboxylates, i.e., iron(III) lactate, Fe(CH3CHOHCOO)3, iron(III) tartrate, Fe2(C4H4O6)3 and iron(III) citrate, Fe(C6H5O7) · 5H2O has been studied in static air atmosphere in the temperature range 298–773 K employing Mössbauer, infrared spectroscopies and themogravimetric methods. The compounds directly decompose to -Fe2O3 without undergoing reduction to iron(II) intermediates. An increase in particle size of -Fe2O3 has been observed with increasing decomposition temperature. The thermal stability follows the sequence: iron(III) tartrate > iron(III)citrate > iron(III)lactate.  相似文献   
6.
The thermolysis of sodium hexa/benzoato/ferrate/III/, i. e. Na3[Fe/C6H5COO/6].4.5H2O has been investigated at different temperatures in air using Mössbauer, infrared spectroscopic and derivatographic techniques /DTG, DTA, TG/. The thermal decomposition proceeds without the reduction of iron/III/. An increase in particle size of -Fe2O3 formed during thermolysis has been observed with increasing temperature. The end product, -NaFeO2 is formed as a result of the solid state reaction between -Fe2O3 and sodium carbonate.  相似文献   
7.
The solid state reactions between ferrous oxalate dihydrate i.e. FeC2O4.2H2O and unsubstituted/ substituted aniline hydrochlorides have been studied. The products [FeCl/oxH/. AN-Cl] have been characterized by elemental analysis, infrared and Mössbauer spectroscopic techniques. The kinetic studies for the reactions have been performed at various temperatures for fixed particle sizes at constant compaction. The following order of reactivity has been observed: unsubstituted > p-substituted > m-substituted o-substituted.  相似文献   
8.
The thermal decomposition of cesium tris(oxalato) ferrate(III) dihydrate, Cs3 Fe(ox)3 2H2O has been studied at various temperatures in air, employing Mössbauer and infrared spectroscopies, and thermogravimetric methods. The complex undergoes reduction to an iron(II) intermediate at 473 K. The particle size of -Fe2O3 formed during thermolysis increases with increasing decomposition temperature. Finally, a solid state reaction between -Fe2O3 and cesium carbonate/oxide occurs, leading to the formation of fine particles of cesium ferrite (CsFeO2).  相似文献   
9.
Abstract

In this article, two static routing algorithms have been proposed and compared to some of the existing algorithms on the basis of blocking probability. The two proposed static routing and wavelength assignment algorithms reduce the blocking probability to maximize the utilization of the network. All of these algorithms are analyzed and compared with four wavelength assignment schemes, which are first-fit, random, most used, and least used. It is shown that our proposed static algorithms give the best performance for first-fit wavelength assignment and most used wavelength assignment strategies with reduced complexity. For least used wavelength assignment and random wavelength assignment, 1 fixed and 2 alternate routing algorithm gives the lowest blocking probability.  相似文献   
10.
A new set of free-base and zinc(II)-metallated, β-pyrrole-functionalized unsymmetrical push–pull porphyrins were designed and synthesized via β-mono- and dibrominated tetraphenylporphyrins using Sonogashira cross-coupling reactions. The ability of donors and acceptors on the push–pull porphyrins to produce high-potential charge separated states was investigated. The porphyrins were functionalized at the opposite β,β′-pyrrole positions of porphyrin ring bearing triphenylamine push groups and naphthalimide pull groups. Systematic studies involving optical absorption, steady-state and time-resolved emission revealed existence of intramolecular type interactions both in the ground and excited states. The push–pull nature of the molecular systems was supported by frontier orbitals generated on optimized structures, wherein delocalization of HOMO over the push group and LUMO over the pull group connecting the porphyrin π-system was witnessed. Electrochemical studies were performed to visualize the effect of push and pull groups on the overall redox potentials of the porphyrins. Spectroelectrochemical studies combined with frontier orbitals helped in characterizing the one-electron oxidized and reduced porphyrins. Finally, by performing transient absorption studies in polar benzonitrile, the ability of push–pull porphyrins to produce charge-separated states upon photoexcitation was confirmed and the measured rates were in the range of 109 s−1. The lifetime of the final charge separated state was around 5 ns. This study ascertains the importance of push–pull porphyrins in solar energy conversion and diverse optoelectronic applications, for which high-potential charge-separated states are warranted.  相似文献   
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