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81.
Li Kaidi Zhang Fangfang Wu Haoran Wang Yina Du Jimin Lu Yayun Wang Weimin Zhao Guoyan Kang Dae Joon 《Journal of Solid State Electrochemistry》2018,22(12):3977-3983
Journal of Solid State Electrochemistry - Here, we demonstrate the synthesis of sheet-shaped Co2P grown on carbon cloth (sheet-shaped Co2P-CC) through a facile route. Electrochemical measurements... 相似文献
82.
83.
By implementing heterogeneous sampling communication mechanism, this article addresses the exponential synchronization issue of drive–response chaotic neural networks (CNNs) with interval time-varying delays by simultaneously taking into account the semi-Markovian switchings and saturating actuators. More specifically, a semi-Markovian jumping model whose transition rates (TRs) are not constant but depends on the sojourn time (ST) is introduced to characterize the stochastic changing among the interaction of CNNs, which makes the NNs model under consideration more suitable for some actual circumstances. More particularly, we assume that the sampling intervals are heterogeneous and time-varying, which may be more practical in real-life applications than homogeneous sampling policy. Additionally, by introducing some new terms, one novel time-dependent Lyapunov–Krasovskii function (LKF) is ingeniously constructed, which can fully capture the characteristic information of heterogeneous sampling pattern. Benefitting from the introduced relaxed free-weighting matrices (FWM) and resorting to the formed LKF, some sampling-interval-dependent sufficient conditions for controller design of the resulting semi-MJNNs error system are established and expressed by linear matrix inequalities (LMIs). These LMIs-based constraints can be effectively checked by utilizing the available software packages. Therein, the developed synchronization criteria dependent on both the lower and upper bounds of sampling periods, and the available information about the actual sampling pattern is fully considered. Ultimately, two numerical examples are provided to demonstrate the feasibility and practicability of our theoretical findings. 相似文献
84.
85.
Linex损失及PA样本下单边截断型分布族参数函数的EB估计 总被引:1,自引:0,他引:1
在Linex损失函数下,运用同分布PA样本密度函数的核估计方法,构造了一类单边截断型分布族参数函数的EB估计,并建立了它的收敛速度.在一定条件下,证明了这个收敛速度可充分接近1. 相似文献
86.
《Polyhedron》2002,21(12-13):1229-1234
Reaction between 8-aminoquinoline and benzenesulfonyl, toluene-4-sulfonyl and naphthalene-2-sulfonyl chlorides in a basic medium leads to the formation of the corresponding sulfonamides. Reaction of these sulfonamides with Ni(II) salts leads to the formation of the corresponding complexes, with a NiL2 stoichiometry. Determination of the crystalline structure by X-ray diffraction shows an octahedral environment for the Ni(II) ions, sulfonamides acting as bidentate ligands and two solvent molecules completing the octahedral coordination. The spectroscopic and magnetic properties of these compounds are also discussed. 相似文献
87.
Graphene was prepared by electrochemical reduction of exfoliated graphite oxide at cathodic potentials, and used to fabricate a graphene-modified glassy carbon electrode (GCE) which was applied in a sensor for highly sensitive and selective voltammetric determination of hydroquinone (HQ). Compared to a bare (conventional) GCE, the redox peak current for HQ in pH 5.7 acetate buffer solution is significantly increased, indicating that graphene possesses electrocatalytic activity towards HQ. In addition, the peak-to-peak separation is significantly improved. The modified electrode enables sensing of HQ without interference by catechol or resorcinol. Under optimal conditions, the sensor exhibits excellent performance for detecting HQ with a detection limit of 0.8?μM, a reproducibility of 2.5% (expressed as the RSD), and a recoveries from 98.4 to 101.2%. Figure
Graphene based glassy carbon electrode was used to determine hydroquinone in the simultaneous presence of it isomers of catechol (CC) and resorcinol (RC). The desired sensitivity and selectivity is attributed to the good conductivity and excellent electrocatalytic ability of graphene. 相似文献
88.
To explore the coordination abilities of nitronyl nitroxide ligands, two ligands substituted with quinoxaline ( L1 ) and 2‐phenyl‐1, 2, 3‐triazole ( L2 ) and their NiII and ZnII complexes: Ni( L1 )(hfac)2 ( 1 ), Ni( L2 )(hfac)2 ( 2 ), and Zn( L2 )(hfac)2 ( 3 ) (hfac = hexafluoroacetylacetonate), were synthesized and characterized. X‐ray single‐crystal diffraction analysis shows that compound 1 has a mononuclear structure, which is further linked into a three‐dimensional (3D) supramolecular network by C–H ··· F hydrogen‐bonding, C–H ··· π, and π ··· π stacking interactions. Complexes 2 and 3 have similar mononuclear structures, which are further linked into one‐dimensional (1D) supramolecular chains by various intermolecular weak interactions, such as C–H ··· F hydrogen‐bonding, and π ··· π stacking interactions. The results indicate that the steric bulk of L1 and L2 and the existence of hexafluoroacetylacetonate (hfac) play important roles in controlling the formation of the final frameworks of complexes 1 – 3 . Moreover, the luminescent properties of the ligands and their complexes were investigated in detail. 相似文献
89.
《Solid State Sciences》2012,14(9):1385-1391
The phase constitution and phase structure of Zn0.5Ti1−xZrxNbO4 ceramics were analyzed by multiphase structure refinement. The diffraction patterns of Zn0.5Ti1−xZrxNbO4 showed that the ixiolite phase ZnTiNb2O8 and rutile phase Zn0.15Nb0.30Ti0.55O2 were obtained. The distortion of oxygen octahedron, bond valence of Ti-site and volume of oxygen octahedron were calculated. For the main phase ZnTiNb2O8, with substitution of Zr4+ for Ti4+, the distortion of oxygen octahedron and the bond valence of Ti-site increased. The increase of Ti-site bond valence led to a harder rattling of Ti cations of the specimens. As a result, the contribution of the rattling effect to the polarizabilities of the specimens decreased, and subsequently the dielectric constant decreased. With increasing fraction of Zn0.15Nb0.30Ti0.55O2, the Qf value decreased. The decrease of τf was mainly attributed to the increase of Ti-site bond valence. With the Ti-site bond valence increasing, the bonding strength between oxygen ion and Ti4+ ion became stronger, and the dilution of the average ionic polarizability decreased. 相似文献
90.
《Solid State Sciences》2012,14(9):1361-1366
Two structurally diverse coordination polymers [Ce2(m-BDC)2(m-HBDC)2(MOPIP)2·3/2H2O]n (1) and [Pr2(m-BDC)3(MOPIP)2·H2O]n(2) have been synthesized by hydrothermal reaction of lanthanide chloride with mixed ligands benzene-1,3-dicarboxylic acid and 2-(4-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (MOPIP). The crystal structures of the complexes are zipper-like chains of octacoordinate Ln3+ ions, in which Ln3+ ions are bridged in different coordination modes by m-BDC2+ and decorated by MOPIP ligands. These chains are further assembled into three-dimensional supramolecular framework by π⋯π stacking and hydrogen bonding interactions. The fluorescent property and thermal stability were also investigated. Additionally, Natural bond orbital (NBO) analysis of complex 2 shows a weak covalent interaction between the coordinated atoms and Pr3+ ions. 相似文献