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201.
We prove that any global bounded solution of a phase field model with memory terms tends to a single equilibrium state for
large times. Because of the memory effects, the energy is not a Lyapunov function for the problem and the set of equilibria
may contain a nontrivial continuum of stationary states. The method we develop is applicable to a more general class of equations
containing memory terms.
Received August 11, 2000; accepted September 25, 2000. 相似文献
202.
Xiao Zhang Eric J. Watson Conor A. Dullaghan Sergiu M. Gorun Dwight A. Sweigart 《Angewandte Chemie (International ed. in English)》1999,38(15):2206-2208
Stable unsaturated heterocycles such as benzofuran are difficult to remove from petroleum by conventional catalytic hydrotreating. However, in a model system, coordination of Mn(CO)3+ to the aromatic ring of benzofuran activates the C−O bond towards insertion of [Pt(PPh3)2] [Eq. (1)]. The insertion is preceded by precoordination to the furan C=C bond; thus, the 2,3-dihydro analogue of 1 , which lacks this double bond, does not undergo insertion of the Pt moiety. 相似文献
203.
Ana Arauzo Elena Bartolom Javier Luzn Pablo J. Alonso Angelica Vlad Maria Cazacu Mirela F. Zaltariov Sergiu Shova Juan Bartolom Constantin Turta 《Molecules (Basel, Switzerland)》2021,26(18)
We present the magnetic properties of the metal-organic framework {[CoCxAPy]·2.15 H2O}n (Cx = bis(carboxypropyl)tetramethyldisiloxane; APy = 4,4′-azopyridine) (1) that builds up from the stacking of 2D coordination polymers. The 2D-coordination polymer in the bc plane is formed by the adjacent bonding of [CoCxAPy] 1D two-leg ladders with Co dimer rungs, running parallel to the c-axis. The crystal packing of 2D layers shows the presence of infinite channels running along the c crystallographic axis, which accommodate the disordered solvate molecules. The Co(II) is six-coordinated in a distorted octahedral geometry, where the equatorial plane is occupied by four carboxylate oxygen atoms. Two nitrogen atoms from APy ligands are coordinated in apical positions. The single-ion magnetic anisotropy has been determined by low temperature EPR and magnetization measurements on an isostructural compound {[Zn0.8Co0.2CxAPy]·1.5 CH3OH}n (2). The results show that the Co(II) ion has orthorhombic anisotropy with the hard-axis direction in the C2V main axis, lying the easy axis in the distorted octahedron equatorial plane, as predicted by the ab initio calculations of the g-tensor. Magnetic and heat capacity properties at very low temperatures are rationalized within a S* = 1/2 magnetic dimer model with anisotropic antiferromagnetic interaction. The magnetic dimer exhibits slow relaxation of the magnetization (SMM) below 6 K in applied field, with a τlf ≈ 2 s direct process at low frequencies, and an Orbach process at higher frequencies with U/kB = 6.7 ± 0.5 K. This compound represents a singular SMM MOF built-up of Co-dimers with an anisotropic exchange interaction. 相似文献
204.
Almost global solutions are constructed to three-dimensional, quadratically nonlinear wave equations. The proof relies on generalized energy estimates and a new decay estimate. The method applies to equations that are only classically invariant, such as the nonlinear system of hyperelasticity. © 1996 John Wiley & Sons, Inc. 相似文献
205.
Bahrin Lucian G. Clima Lilia Shova Sergiu Rosca Irina Cojocaru Corneliu Bejan Dana Sardaru Monica C. Marangoci Narcisa Lozan Vasile Rotaru Alexandru 《Research on Chemical Intermediates》2019,45(2):453-469
Research on Chemical Intermediates - Tetrazole- and nitrile-containing bimesitylene derivatives with potential use in coordination chemistry were synthesized and characterized, and their structural... 相似文献
206.
Stoian Sergiu Alexandru Gabor Augusta Raluca Albu Ana-Maria Nicolae Cristian Andi Raditoiu Valentin Panaitescu Denis Mihaela 《Journal of Thermal Analysis and Calorimetry》2019,138(4):2469-2480
Journal of Thermal Analysis and Calorimetry - Polypropylene (PP) is a versatile polymer, with a wide range of applications, from household appliances to packaging and automotive components.... 相似文献
207.
208.
Dmitri V. Zagorevskii Sergiu P. Palii John L. Holmes 《Journal of the American Society for Mass Spectrometry》1994,5(9):814-825
The formation of diethyl halonium ions (C2H5)2X+ (X = Cl, Br, I) by a variety of ion-molecule reactions is described. The dissociation characteristics (metastable and collision-induced dissociation mass spectra) of these ions and their isomers were studied in detail. Some of the neutral fragmentation products were examined by their collision-induced dissociative ionization mass spectra. The participation of classical (1, CH3CH2X+CH2CH3) and nonclassical forms of the ions was considered. Dissociation reactions for which loss of positional identity of H-D atoms took place, for example C2H4 loss (a common fragmentation of metastable ions) and C2H5 + formation, were interpreted as involving nonclassical ions, 2. It was concluded that the ion-molecule reactions produced both ion structures, but in different halogen-dependent proportions. For (C2H5)2C1+ ions, 2 is the major species, for (C2H5)2Br+ both 1- and 2-type ions are generated, whereas for (C2H5)2I+ the classical form 1 must be the predominant structure. 相似文献
209.
210.