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41.
The vacuum fluctuation (VF) effects on the properties of the hyperonic neutron star matter are investigated in the framework of the relativistic mean field (RMF) theory. The VF corrections result in the density dependence of in-medium baryon and meson masses. We compare our results obtained by adopting three kinds of meson-hyperon couplings. The introduction of both hyperons and VF corrections softens the equation of state (EoS) for the hyperonic neutron star matter and hence reduces hyperonic neutron star masses. The presence of the δ field enlarges the masses and radii of hyperonic neutron stars. Taking into account the uncertainty of meson-hyperon couplings, the obtained maximum masses of hyperonic neutron stars are in the range of 1.33M⊙-1.55M⊙. 相似文献
42.
在液膜拉脱过程中,对吊环的受力以及受力的变化情况进行分析,以便正确测量求得液体表面张力,减少α的实验测量误差。 相似文献
43.
本文研究了匀质悬链的几何形状为悬链线和抛物线的力学条件;探讨了悬链形状与外力作用分布的一般关系;得到了一系列与悬链线有关的参数计算公式. 相似文献
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45.
《Solid State Sciences》2004,6(5):461-468
The hydrothermal reactions of appropriate vanadium oxides and copper(II) salts with bisterpy in the presence of phosphoric acid or fluorophosphoric acid yield the Cu(II)-bisterpy/oxovanadium phosphate materials [{Cu2(bisterpy)}V3O5(HPO4)2(PO4)] (1) and [{Cu2(bisterpy)}V2O5(HPO4)2] (2). Compound 1 is layered material, consisting of inorganic {V3O5(HPO4)2(PO4)}n4n− chains propagating parallel to the crystallographic a-axis, linked in the second dimension through binuclear {Cu2(bisterpy)}4+ units. The chain is constructed from corner-sharing {V4O10(PO4)2}6− and {V2O2(PO4)4}6− cluster building blocks. There are two distinct vanadium sites: a tetrahedral {V(V)O4} site and a square pyramidal {V(IV)O5} center. The Cu(II)-bisterpy subunits are linked to the vanadophosphate chains through phosphate oxygen atoms exclusively. In contrast, the structure of 2 is three-dimensional, exhibiting inorganic {Cu2V2O5(HPO4)2}n networks linked through bisterpy bridges to provide the overall three-dimensional connectivity. The oxovanadium subunit consists of the well-documented {V2O7} binuclear unit of corner-sharing tetrahedral. 相似文献
46.
The preparation and characterization of nanoparticle TiO2/Ti films and their photocatalytic activity
《Journal of Physics and Chemistry of Solids》2003,64(4):615-623
Nanoparticle TiO2/Ti films were prepared by a sol–gel process using Ti(OBu)4 as raw material, the as-prepared film samples were also characterized by TG-DTA, XRD, TEM, SEM, XPS, DRS, PL, SPS and EFISPS testing techniques. TiO2 nanoparticles experienced two processes of phase transition, i.e. amorphous to anatase and anatase to rutile at the calcining temperature range from 450 to 700 °C. TiO2 nanoparticles calcined at 600 °C had similar composition, structure, morphology and particle size with the internationally commercial P-25 TiO2 particles. Thus, the conclusion that 600 °C might be the most appropriate calcining temperature during the preparation process of nanoparticle TiO2/Ti film photocatalysts could be made by considering the main factors such as the properties of TiO2 nanoparticles, the adhesion of nanoparticle TiO2 film to Ti substrate, the effects of calcining temperature on Ti substrate and the surface characteristics and morphology of nanoparticle TiO2/Ti film for the practice view. The Ti element mainly existed on the nanoparticle TiO2/Ti(3) film calcined at 600 °C as the chemical state of Ti4+, while O element mainly existed as three kinds of chemical states, i.e. crystal lattice oxygen, hydroxyl oxygen and adsorbed oxygen with increasing band energy. Its photoluminescence (PL) spectra with a peak at about 380 nm could be observed using 260 nm excitation, possibly resulting from the electron transition from the bottom of conduction band to the top of valence band. The PL peak position was nearly the same as the onset of its diffuse reflection spectra (DRS) and surface photovoltage spectroscopy (SPS), demonstrating that the effects of the quantum size on optical property were greater than that of the Coulomb and surface polarization. The PL spectra with two peaks related to the anatase and rutile, respectively, could be observed using the excited wavelength of 310 nm. Weak PL spectra could be observed using the excited wavelength of 450 nm, resulting from surface states. In addition, during the experimental process of the photocatalytic degradation phenol, the photocatalytic activity of nanoparticle TiO2/Ti film with three layers calcined at 600 °C was the highest. 相似文献
47.
连通图G的Balaban指标(也称J指标)定义为J=J(G)=(|E(G)|)/μ+1∑_(uυ∈E(G)),其中σ_G(u)=∑(w∈V(G)d_G(u,w)此处μ是基圈数.Balaban指标常用于各种QSAR和QSPR的研究.本文根据Balaban指标的计算公式及文中提到的变换方式,我们得到了一些序关系.基于这些序关系,我们确定了n个顶点的树中具有最小Balaban指标的前21个树. 相似文献
48.
The max-cut problem is a classical NP-hard problem in graph theory. In this paper, we adopt a local search method, called MCFM, which is a simple modification of the Fiduccia-Mattheyses heuristic method in Fiduccia and Mattheyses (Proc. ACM/IEEE DAC, pp. 175?C181, 1982) for the circuit partitioning problem in very large scale integration of circuits and systems. The method uses much less computational cost than general local search methods. Then, an auxiliary function is presented which has the same global maximizers as the max-cut problem. We show that maximization of the function using MCFM can escape successfully from previously converged discrete local maximizers by taking increasing values of a parameter. An algorithm is proposed for the max-cut problem, by maximizing the auxiliary function using MCFM from random initial solutions. Computational experiments were conducted on three sets of standard test instances from the literature. Experimental results show that the proposed algorithm is effective for the three sets of standard test instances. 相似文献
49.
Guocai Zheng 《合成通讯》2019,49(7):933-941
An efficient protocol for the synthesis of cycloalkyl carboxylates and alcohols from cyclic olefins is described. The cyclic olefins were converted to corresponding target molecules under solvent-free conditions catalyzed by two novel multi-SO3H functionalized multi heteropolyanion-based ionic hybrids through one-pot consecutive addition esterification and hydrolysis reactions. This approach has several advantages, including high yield, simple workup and simple purification. 相似文献
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