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991.
V. A. Shagun V. I. Smirnov L. G. Shagun S. G. Shevchenko Yu. L. Frolov 《Journal of Structural Chemistry》2006,47(5):831-838
The potential interaction surface between polyhydrated monomethyl mercury cation and 1-chloro-2.2-propane dithiol has been studied by quantum chemical methods. The system generates the hydroxonium cation due to the interaction, which is a demethylating agent for methylmercury. The total thermal balance of the demethylation reaction is 244.5 kJ/mol, the activation energy of the limiting stage in the process has a value of 39.1 kJ/mole. 相似文献
992.
New very stable quasi-planar clusters of bare boron are found by systematic ab initio density functional and quantum chemical methods. They are composed of dove-tailed hexagonal pyramids different from the classical forms of - or β-rhombohedral boron crystallines. The quasi-planar structures are considered to be fragments of quasi-planar surfaces, which can easily be obtained and constructed from a basic unit of hexagonal pyramids. A new investigation on double layers of boron quasi-planar surfaces shows an increase in the stability of the system which can be related to the overlap of π-orbitals between the layers. Therefore, we predict the existence of a series of parallel boron layers, as in graphite. These proposed surfaces can serve as lightweight protective armor, as a neutron-absorber material in fission reactions, or as very high temperature semiconductors. 相似文献
993.
A systematic and fundamental approach to associating mixtures is presented. It is shown how the thermodynamic functions may be computed starting from a partition function based on the cluster concept such as occurs in chemical theory. The theory provides a basis for and an extension of the existing chemical theory of (continuous) association. It is applicable to arbitrary association schemes. Analysis of separate cases is not necessary. The assumptions that were made to allow the development were chosen such as to make the principle of reactivity valid. It is this same principle that links various theories: the chemical theory of continuous association, the lattice fluid hydrogen bonding model, and first-order perturbation theory. The equivalence between these theories in appropriate limits is shown in a general and rigorous way. The theory is believed to provide a practical framework for engineering modeling work. Binary interaction parameters can be incorporated. The association scheme is accounted for by a set of generic equations, which should facilitate robust implementation in computer programs. 相似文献
994.
995.
996.
采用甚高频等离子体增强化学气相沉积技术成功地制备了不同硅烷浓度和辉光功率条件下的微晶硅电池.电池的J-V测试结果表明:在实验的硅烷浓度和功率范围内,随硅烷浓度的降低和功率的加大,对应电池的开路电压逐渐变小;硅烷浓度的不同对电池的短路电流密 度有很大的影响,但功率的影响在实验研究的范围内不是很显著.对于微晶硅电池,N层最好 是非晶硅,这是因为一方面可以降低对电流的横向收集效应,另一方面也降低了电池的漏电概率,提高了电池的填充因子.
关键词:
微晶硅太阳电池
甚高频等离子体增强化学气相沉积 相似文献
997.
分析与综述了医学图像归档与通信系统(PictureArchivingandCommunicationSystem,简称PACS的研究状况,提出了适用于国内医院的PACS设计方案,并对建立国内PACS的著于问题进行了探讨.实践表明该系统设计合理,通用性强,适合国内医院现代化管理的要求. 相似文献
998.
A new chemical vapor deposition (CVD) method, called ionization CVD, was developed, to produce non-agglomerated nanoparticles in which reactant gases are charged. A sonic-jet corona discharger was used as an ionizer in the developed nanoparticle generator. For a tetraethylorthosilicate (TEOS)/O2 chemical system, SiO2 nanoparticles were prepared. All particles formed by the ionization CVD were charged unipolarly. SEM micrographs of particles showed that the repulsive Coulombic force between charged particles reduces their coagulation rate and produces non-agglomerated nanoparticles that have a relatively high number concentration and small size. An external field was used to collect the charged particles onto Si wafers. These collected samples indicated that the deposition of charged particles could be controlled by the external electric field. Particle concentration measurement with a condensation nucleus counter at various TEOS concentrations suggested the particle formation mechanism in the ionization CVD was an ion-induced nucleation. 相似文献
999.
Vazid Ali Raminder Kaur Sukhmehar Singh H.P.S. Kang M. Husain 《Journal of Physics and Chemistry of Solids》2006,67(4):659-664
The structural modification and properties of polymeric materials are of utmost importance in deciding their applications. In the present study, the synthesis of polyaniline (PANI) has been carried out via chemical oxidation in acidic medium by potassium-dichromate and the yield of synthesized polyaniline was found to be 75-80%. The copper per chlorate tetrabenzonitrile salt (CuClO4·4BN) used for chemical doping in synthesized polyaniline is stable in organic solvent like acetonitrile (AN) and benzonitrile (BN). The effect of Cu+1 oxidation state (dopant) in polyaniline has been characterized by FTIR. Electrical and dielectric measurements show the decrease in the intensity of the Cu+1 salt signal and the appearance of a radical signal due to the formation of oxidative coupled in polymeric species. Electrical and dielectric properties of doped polyaniline samples show significant changes due to the effect of dopant (CuClO4·4BN). It is observed that the conductivity is contributing both by formation of ionic complex and particularly dominated by electronic due to the mobility of charge carriers along the polyaniline chain. 相似文献
1000.
采用射频磁控溅射方法在纯N2气氛中沉积了非晶CNx薄膜样品,并 在真空中退火至900 ℃.对高温退火引起的CNx薄膜化学成分、键合结构及其场发射特性方面的变 化进行研究.用傅里叶变换红外光谱和x射线光电子能谱分析样品的内部成分及键合结构的变化,其中sp2键及薄膜中N的含量与薄膜的场发射特性密切相关.退火实验的结果表明 高温退火可以导致CNx薄膜中N含量大量损失,并在薄膜中形成大量sp2<
关键词:
x薄膜')" href="#">CNx薄膜
化学键合
退火温度
场致电子发射 相似文献