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111.
B.C. Gou 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,5(1):39-45
Seven low-lying triply exited states of lithium-like oxygen and neon are calculated with the multichannel saddle-point and
saddle-point complex-rotation methods. The term energies are given for these excited states, along with level shifts and partial
Auger widths from dominant decay channels. The mass polarization effect and relativistic corrections are included. The radiative
transition rates are also calculated. These results are compared with other theoretical data in the literature.
Received: 25 May 1998 / Revised: 28 July 1998 / Accepted: 25 August 1998 相似文献
112.
运用模部分析方法考察了小Bond数条件下圆柱贮箱中弯曲静液面对液体晃动模态的重构作用.研究表明,圆柱贮箱中的液体作小幅晃动时,参与晃动的各阶基本模态的正交性若仅由Bessel模部来给出,则弯曲静液面将使各阶模态加权耦合,形成新的特征模态;参与晃动的各阶基本模态的正交性若由三角函数模部来给出,则弯曲静液面将独立改变各阶模态的固有频率,各阶模态之间不耦合.运用新的重构模态来研究圆柱贮箱中液体的横向受迫晃动,给出了其模态选择特征. 相似文献
113.
利用改进的马鞍点方法,截断变分方法,并考虑能量的相对论修正和质量极化效应,计算和研究了类理等电子系列的两个四重态(1s2p2p)4P0和(1s2s2p)4Pe态的精细结构和平均跃迁波长,并与实验和其它理论计算结果进行了比较。 相似文献
114.
Yang An Bo-Sheng Zhang Ya-Nan Ding Zhe Zhang Xue-Ya Gou Xue-Song Li Xiaolei Wang Yuke Li Yong-Min Liang 《Chemical science》2021,12(39):13144
This report describes palladium-catalyzed C–H glycosylation and retro Diels–Alder tandem reaction via structurally modified norbornadienes (smNBDs). smNBDs were proposed to regulate the reactivity of the aryl-norbornadiene-palladacycle (ANP), including its high chemoselectivity and regioselectivity, which were the key to constructing C2 and C3 unsubstituted C4-glycosidic indoles. The scope of this substrate is extensive; the halogenated six-membered and five-membered glycosides were applied to the reaction smoothly, and N-alkyl (primary, secondary and tertiary) C4-glycosidic indoles can also be obtained by this method. In terms of mechanism, the key ANP intermediates characterized by X-ray single-crystal diffraction and further controlled experiments proved that the migration-insertion of smNBDs with phenylpalladium intermediate endows them with high chemo- and regioselectivity. Finally, density functional theory (DFT) calculation further verified the rationality of the mechanism.This report describes palladium-catalyzed C–H glycosylation and retro Diels–Alder tandem reaction via structurally modified norbornadienes (smNBDs). 相似文献
115.
X.N. Jiang D. Xu D.L. Sun D.R. Yuan M.K. Lu S.Y. Gou X.L. Yu 《Crystal Research and Technology》2002,37(1):43-49
New growth phenomena ‐ direct incorporation of aggregates have been observed on the {110} faces of cadmium mercury thiocyanate CdHg(SCN)4 crystals by atomic force microscopy. These aggregates grow in two forms: some directly cover up the steps and forms new growth layers; while others are just incorporated at the step edges. These aggregates, which are mostly oriented along [111] direction, are formed by small columnar structural units. The aggregates have the similar structure of CdHg(SCN)4 crystals and greatly vary in nature with the variation of solution supersaturation σ and growth time t. With the increase of σ the aggregates become larger, consistent with the variation of growth units dimension with the supersaturation; and with the increase of growth time the aggregates become more structurally substantial. These observations have led to a new understanding about the crystal growth. 相似文献
116.
The last decade has witnessed multiple thermally responsive materials emerge as a significant class of stimuli‐responsive materials. These materials are elaborately designed and exert interesting properties. Herein, an overview of thermally responsive materials with respect to design strategies, fabrication procedures, and their applications is presented. Recently reported thermally responsive materials are highlighted. Then, applications of thermally responsive materials in bioimaging are summarized. 相似文献
117.
The geometrical structure, stability, magnetism, and electronic structure of bimetallic clusters AuM2 and Au2M2, where M are 4d transition metal elements, are investigated systematically by using the first-principles method based on
density functional theory. The calculation results show that there is a large amount of low-energy isomers with the very similar
structure. AuM2 and Au2M2 clusters display dramatic magnetism. The magnetic moment of the 4d element is either enhanced or weakened with respect to
the bulk value, which is largely dependent on the orbital exchange-splitting.
Supported by the National Natural Science Foundation of China (Grant Nos. 10674015 and 10604035) 相似文献
118.
采用基于密度泛函理论的第一性原理方法系统研究了Au与3d过渡元素构成的混合小团簇的结构、稳定性、电子结构及磁性,得到了Au与3d过渡元素构成的混合小团簇的稳定结构.计算结果表明,Au与3d元素可形成大量的低能异构体,特别是有些异构体在结构上极相近,这不同于共价或离子键类型的团簇.与纯过渡金属团簇类似,这类团簇也表现出复杂的磁性.过渡金属元素的磁矩相比体材料而言既有增强的、也有减弱的,与轨道的交换劈裂密切相关.对于基态构型,AuCr2,Au2Cr2关键词:
密度泛函理论
第一性原理方法
团簇
电子结构 相似文献
119.
120.
Treatments of nitrogen-containing heterocyclic dithioether ligands, 1,2-bis(4-(pyridin-3-yl) pyrimidin-2-ylthio) ethane (L1) and 1,3-bis (4-(pyridin-3-yl) pyrimidin-2-ylthio) propane (L2), with zinc or cadmium salts have resulted in the interesting frameworks with structural motifs from a mononuclear macrocycle or a dinuclear macrocycle to an one-dimensional structure. A small difference of the alkyl length between L1 and L2 led to conspicuous changes of the fluorescent properties of both ligands and their complexes. Mainly due to the size of metal atoms, structures of [ZnL2I2] (1) and [CdL2I2] (2) are varied from a mononuclear macrocycle to a 1D framework, while {[ZnL2(H2O)4](ClO4)2}2 (3) and {[CdL2(H2O)4](ClO4)2}2 (4) are dinuclear macrocycles in which perchlorate anions may play an important template role. As for complexes 5–8 ([ZnL1I2]n (5), [CdL1I2]n (6), {{[ZnL12(H2O)4](ClO4)2}0.5 · L10.5 · CH3OH} (7), {{[Cd0.5L1(H2O)2](ClO4)}2 · CH3OH · L1} (8)), the self-assemble processes were mainly directed by the organic ligand in the reactions of L1 with metal salts. Complexes 1–4 exhibit blue fluorescence emissions, among which 1 and 2 may be suitable as candidates for blue fluorescent materials. 相似文献