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101.
Alper Tolga Çolak Handan Günay Ersin Temel Orhan Büyükgüngör Ferdağ Çolak 《Transition Metal Chemistry》2017,42(1):85-93
Two 5-hydroxyisophthalate complexes of nickel(II), formulated as [Ni(μ-Hhip)(2-hepy)2] n (1) and [Ni2(μ-Hhip)2(dap)4] n (2) (H3hip = 5-hydroxyisophthalic acid, 2-hepy = 2-(2-hydroxyethyl)pyridine, dap = 1,3-diaminopropane), have been synthesized and characterized by chemical and spectroscopic methods. The molecular structures of the complexes have been determined by single-crystal X-ray diffraction analysis. The Ni(II) centres have distorted octahedral geometries in both crystals. Furthermore, both complexes have 1D chain structures in which the individual chains are linked together via hydrogen bonds to give 3D frameworks. Evaluation of the complexes by the agar diffusion method showed that they have weak antibiotic activities against the tested microorganisms. 相似文献
102.
For a d‐dimensional diffusion of the form dXt = μ(Xt)dt + σ(Xt)dWt and continuous functions f and g, we study the existence and uniqueness of adapted processes Y, Z, Γ, and A solving the second‐order backward stochastic differential equation (2BSDE) If the associated PDE has a sufficiently regular solution, then it follows directly from Itô's formula that the processes solve the 2BSDE, where ?? is the Dynkin operator of X without the drift term. The main result of the paper shows that if f is Lipschitz in Y as well as decreasing in Γ and the PDE satisfies a comparison principle as in the theory of viscosity solutions, then the existence of a solution (Y, Z,Γ, A) to the 2BSDE implies that the associated PDE has a unique continuous viscosity solution v and the process Y is of the form Yt = v(t, Xt), t ∈ [0, T]. In particular, the 2BSDE has at most one solution. This provides a stochastic representation for solutions of fully nonlinear parabolic PDEs. As a consequence, the numerical treatment of such PDEs can now be approached by Monte Carlo methods. © 2006 Wiley Periodicals, Inc. 相似文献
103.
104.
Bruno Bouchard H. Mete Soner Nizar Touzi 《Journal of Optimization Theory and Applications》2018,178(2):363-382
In this paper, we study the near-optimal control for systems governed by forward–backward stochastic differential equations via dynamic programming principle. Since the nonsmoothness is inherent in this field, the viscosity solution approach is employed to investigate the relationships among the value function, the adjoint equations along near-optimal trajectories. Unlike the classical case, the definition of viscosity solution contains a perturbation factor, through which the illusory differentiability conditions on the value function are dispensed properly. Moreover, we establish new relationships between variational equations and adjoint equations. As an application, a kind of stochastic recursive near-optimal control problem is given to illustrate our theoretical results. 相似文献
105.
A simple, precise and sensitive spectrofluorimetric method was developed and validated for the determination of ranitidine in pharmaceutical preparations. The method is based on derivatization of ranitidine with 4-fluoro-7-nitrobenzofurazan (NBD-F). The method was successfully validated in accordance to ICH guidelines. The validation characteristics included linearity, limit of detection, limit of quantification, accuracy, precision, specificity and robustness. The method is linear over the range of 40?C1200 ng/mL. The recoveries were ranged from 98.97 to 99.43%. The proposed method was applied for the determination of ranitidine in commercially available tablets. The results were compared with those obtained by reference method using t and F-tests. 相似文献
106.
Nesibe Avcibaşi Murat Uygun M. Emin Çorman Sinan Akgöl Adil Denizli 《Applied biochemistry and biotechnology》2010,162(8):2232-2243
Supermacroporous poly{2-hydroxyethyl methacrylate-co-[N,N-bis(2,6-diisopropylphenyl)-perylene-3,4,9,10-tetracarboxylic diimide]} [poly(HEMA-co-DIPPER)] monolithic cryogel column was prepared by radical cryocopolymerization of HEMA with DIPPER as functional comonomer
and N,N′-methylene-bisacrylamide (MBAAm) as crosslinker directly in a plastic syringe for adsorption of albumin. The monolithic cryogel
contained a continuous polymeric matrix having interconnected pores of 10–50 μm size. Poly(HEMA-co-DIPPER) cryogel was characterized by swelling studies, FTIR, scanning electron microscopy, and elemental analysis. The equilibrium
swelling degree of the poly(HEMA-co-DIPPER) cryogel was 14.7 g H2O/g dry cryogel. Poly(HEMA-co-DIPPER) cryogel was used in the adsorption/desorption of albumin from aqueous solutions. The nonspecific adsorption of albumin
onto plain poly(HEMA) cryogel was very low (3.36 g/g polymer). The maximum amount of albumin adsorption from aqueous solution
in acetate buffer was 40.9 mg/g polymer at pH 5.0. It was observed that albumin could be repeatedly adsorbed and desorbed
with the poly(HEMA-co-DIPPER) cryogel without significant loss of adsorption capacity. 相似文献
107.
Ertuğrul Gazi Sağlam Ömer Çelik Hamza Yılmaz Semra İde 《Transition Metal Chemistry》2010,35(4):399-405
Thionation of 3-methylbutylmagnesium bromide with Lawesson’s Reagent (LR) gave 4-methoxyphenyl (3-methylbutyl)dithiophosphinic
acid (DTPA), and the latter was converted to the ammonium salt (NH4L = Ammonium 4-methoxyphenyl (3-methylbutyl) dithiophosphinate). The complex, trans–bis[4-methoxyphenyl(3–methylbutyl) dithiophosphinato]
nickel(II) [NiL2], was prepared by the reaction of NH4L with NiCl2.6H2O in EtOH. Bis [4-methoxyphenyl (3-methylbutyl) dithiophosphinato]cobalt(II) [(CoL2)2] was also prepared in the same way. The structures of the complexes have been characterized by elemental analysis, FTIR,
1H, 13C, 31P NMR and X-ray diffraction. The single crystal X-ray structures of [NiL2] and [(CoL2)2] show that the nickel complex is square planar while the cobalt counterpart has tetrahedral coordination with a dimeric structure.
Bond lengths, angles, torsion angles and dihedral angles are correlated to the structures and also compared with the literature
data on similar compounds. 相似文献
108.
Çiǧdem Yüksektepe Nezihe Çalişkan Murat Genç Süleyman Servi 《Crystallography Reports》2010,55(7):1188-1193
The titled compound (1), has been synthesized and characterized by IR and 1H-NMR spectroscopy, and single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P-1. The crystal structure is stabilized by C-H…π and aromatic π-π interactions. There are also intramolecular N-H…N and C-H…N
hydrogen bonds in the molecule. The use of quantum chemical calculations to characterise and optimise the choice of material
is illustrated by ab initio treatments. Vibrational frequencies and LUMO-HOMO energy difference of 1 have also been investigated by Density functional theory (DFT) and Hartree-Fock (HF) calculations. Calculated frequencies
are in good agreement with the corresponding experimental data. 相似文献
109.
Nezihe Çalişkan Feyizan Güntepe Çiǧdem Yüksektepe Alaaddin Çukurovalı Orhan Büyükgüngör 《Crystallography Reports》2010,55(7):1183-1187
The title compound C18H21ClN2SO crystallizes with Z = 4 in space group P21/c. The structure of the title compound was characterized by 1H-NMR, 13C-NMR, IR and single crystal diffraction. There are an intermolecular N-H…O hydrogen bond and a C-H…π interactions in crystal
packing. In addition to the molecular geometry and packing obtained from X-ray experiment, the molecular geometry and vibrational
frequencies of the title compound in ground state have been calculated using density functional theory method DFT (B3LYP)
with 6-31G (d, p) basis set. Calculated frequencies, bond lengths, angles and dihedral angles are in good agreement with the corresponding
experimental data. 相似文献
110.
Ergül S 《Journal of chromatographic science》2006,44(9):543-547
Sodium diethyldithiocarbamate (DEDTC) and ammonium pyrolidinedithiocarbamate (PyDTC) are prepared as their Co or Cu (M) complexes [M(DEDTC)(2) and M(PyDTC)(2), respectively]. The complexes are prepared by reactions of DEDTC and PyDTC with metal (II) nitrates, and they are examined for chromatographic properties using thin-layer chromatography systems. These complexes and their mixtures are spotted on the activated and non-activated 250-microm thick thin layers of commercial silica gel (Si-60GF(254)). Pure toluene and a toluene-cyclohexane mixture (3:1, v/v) are used as mobile phases for running the complexes. These chromatographic systems are successfully used for the qualitative analysis of the corresponding metal cations and the separation of components in both M(DEDTC)(2) and M(PyDTC)(2) complex mixtures. In addition, non-activated layers are more successful than activated layers. This study may be useful in understanding the effects of stationary and mobile phase properties, retention mechanisms, and the effects of the nature of metal and ligand type on the chromatographic behavior and parameters [e.g., retention factors, theoretical plate numbers, and resolution] of the complexes. 相似文献