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排序方式: 共有593条查询结果,搜索用时 15 毫秒
461.
1INTRODUCTIONAlotofstudieshaverevealedthatmesocyclicdiaminesandtheirderivativesareversa tilechelatingagentsandtheyshowedunusu... 相似文献
462.
1 INTRODUCTIONBiscyclopentadienyllanthanidechloridesforallthelanthanideelementshavebeensynthesizedandstructurallycharacterized〔1〕.Tert-butylcyclopentadienylisasuitableligandforpreparationoflanthanocenechlorides.Thesynthesesandmolecu-larstructuresof〔(… 相似文献
463.
1 INTRODUCTION There has been an increasing interest in the re- search of diode-pumped solid-state lasers in recent years because of the rapid development of high power diode lasers. The absorption peak of Nd3 ions at about 800 nm corresponding to 4I9/2→ 2H9/2 tran- sition is suitable for commercial laser diode GaAlAs pumping[1]. KLa(MoO4)2 is a kind of disordered crystalline host for lasing rare-earth ions[2], and it belongs to Scheelite (CaWO4) structure[3]. The disorder derives… 相似文献
464.
Syntheses and Crystal Structures of Two 3D Zinc(II) Compounds Involving Coordination and Hydrogen Bonds 总被引:1,自引:1,他引:0
CHEN Bai-Quana b HAN Leia WU Ben-Laia b WU Ming-Yana b HUANG You-Guia b HONG Mao-Chuna a 《结构化学》2006,25(5)
1 INTRODUCTION Self-assembly through coordination and hydrogen bonds has been proved to be a powerful tool for con- structing functional organic crystalline materials[1~4]. Except for the important role of H-bonds in the sta- bilization of structures, hydrogen bonding groups namely hydroxyl, amide groups in adjacent coor- dination polymeric chains or discrete lamellas can form hydrogen bonds, which allow for the assembly of well-formed crystalline solid[5, 6]. Our recent inte- rest is foc… 相似文献
465.
LI Ya-Mina b ZHANG Jian-Juna SHENG Tian-Lua FU Rui-Biaoa HU Sheng-Mina LAI Zhu-Zhia WU Xin-Taoa② a 《结构化学》2006,25(8):891-894
1 INTRODUCTION The transition-metal Schiff base complexes have attracted much attention due to their beautiful struc- tures, multifunctions like catalysis[1~3] and materials science[4~6]. Recently, some Schiff base complexes based on guanidinate ligands have been explored[7~9], and most of them were synthesized by stepwise reactions. Due to the steric and electrical flexibility and abundant donor functionality of the guanidinate species, the ligand may adopt various coordination modes.… 相似文献
466.
XU Hui-Ying a YU Qing-Sen b ZOU Jian-Wei b② WANG Yan-Hua a WANG Hong-Qing b CHEN Xue-Song a a 《结构化学》2006,25(7):811-817
1 INTRODUCTION Halogenated methyl-phenyl ethers (anisoles) are ubiquitous organic compounds in the environment. There are 134 possible congeners consisting of 19 chloroanisoles, 19 bromoanisoles and 96 bromo- chloroanisoles. Although they are not produced… 相似文献
467.
1 INTRODUCTION Quantitative structure-chromatographic retention relationship (QSRR)[1], a method using the computer auxiliary means to perform simulation and predic- tion of organic compounds’ chromatographic reten- tion behavior, has been developed recently. In this process, the first step is how to effectively fetch the information of molecular structure, and transform it into a set of characteristic numeric codes, that is, the so-called molecular structure characterization(MSC). Ge… 相似文献
468.
1 INTRODUCTION Interaction between cations and π electron systems is a kind of common and important non-covalent inter- action[1~21]. It could be observed in many systems, such as gas ion-molecule complexes and biological macromolecular proteins. Especially, in biological macromolecular systems, this interaction is signi- ficant for revealing the structures and functions of proteins or disclosing the atomic essence of protein- ligand effect. Interaction between benzene and metal ions h… 相似文献
469.
Structural parameters of 24 substituted naphthalin compounds were computed at four levels using Hartree-Fock and DFT methods. Based on the experimental data of octanol/water partition coefficient (lgKow),three-parameter (energy of the highest occupied molecular orbital (EHOMO),the most positive atomic net charges of molecule (q+) and molecular average polari-zability (α)) dependent equations were developed using structural parameters as theoretical des-criptors. Especially,lgKow dependent equation calculated at the HF/6-311G** level is more advantageous than others in view of their correlation and predictive abilities. This dependent equation was validated by variance inflation factors (VIF) and t-test methods and used to predict lgKow of eight designed compounds. Upon comparison,the predictive abilities of our work are all more advantageous than those calculated from molecular property calculator program. 相似文献
470.
HAN Qiu-Xiaa ZHANG Da-Lib MA Jian-Ruc WANG Jing-Pingc NIU Jing-Yangc a 《结构化学》2007,26(8):949-954
The synthesis, X-ray crystal structure, thermal properties and electrochemistry of the new complex formulated as {Er(DMSO)7}PW12O40 are reported. The single-crystal X-ray analysis reveals that the crystal crystallizes in the monoclinic system, space group P21/c with a = 11.767(2), b = 14.909(3), c = 34.905(7) , β = 98.97(3)°, Mr = 3591.33, V = 6049(2) 3, Dc = 3.944 g/cm3, Z = 4, GOOF = 1.098, F(000) = 6340, R = 0.0490 and wR = 0.1202. Crystal structure analysis indicates that the Er(Ⅲ) is seven-coordinate with a distorted pentagonal bipyramid and combines to the anion [PW12O40]3- via static electric force. 相似文献