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91.
Nonlinear Dynamics - Two types of constitutive equations consisting of instantaneous and power type hereditary contributions are proposed in order to model generalized capacitor (inductor). The... 相似文献
92.
Wei Peng Henriette S. de Bruijn Timo L. M. ten Hagen Go M. van Dam Jan L. N. Roodenburg Kristian Berg Max J. H. Witjes Dominic J. Robinson 《Photochemistry and photobiology》2020,96(3):708-717
Targeted photodynamic therapy (PDT) in head/neck cancer patients with a conjugate of the anti-epidermal growth factor receptor (EGFR) antibody, Cetuximab and a phthalocyanine photosensitizer IR700DX is under way, but the exact mechanisms of action are still not fully understood. In this study, the EGFR-overexpressing human head/neck OSC-19-luc2-cGFP tumor with transfected GFP gene was used in a skin-fold window chamber model in BALB/c nude mice. The uptake and localization of the conjugate in the tumor and its surrounding normal tissues were studied by an intravital confocal laser scanning microscopy with image analyses. The tumor was also irradiated with 690 nm laser light 24 h after conjugate administration. The vascular and tumor responses were examined by morphological evaluation and immunohistochemistry (IHC). The amount of conjugate in the tumor peaked at 24–48 h after injection. Image analyses of colocalization correlation parameters demonstrated a high fraction of the conjugate IR700DX colocalized in the GFP-expressing tumor cells. PDT-treated tumors showed extensive necrotic/apoptotic destruction with little vascular damage, while IHC showed no HIF-1α expression and decreased EGFR and Ki67 expression with activated caspase-3 overexpression, indicating a direct killing of tumor cells through both necrotic and apoptotic cell death. 相似文献
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PHOTOCHEMOTHERAPY OF CANCER: EXPERIMENTAL RESEARCH 总被引:15,自引:0,他引:15
96.
A Catalytic Oxidative Quinone Heterofunctionalization Method: Synthesis of Strongylophorine‐26 下载免费PDF全文
Kristian M. Jacobsen Henriette N. Tobiesen Line Clemmensen Prof. Dr. Thomas B. Poulsen 《Angewandte Chemie (International ed. in English)》2018,57(31):9805-9809
The preparation of heteroatom‐substituted p‐quinones is ideally performed by direct addition of a nucleophile followed by in situ reoxidation. Albeit an appealing strategy, the reactivity of the p‐quinone moiety is not easily tamed and no broadly applicable method for heteroatom functionalization exists. Shown herein is that Co(OAc)2 and Mn(OAc)3?2 H2O act as powerful catalysts for oxidative p‐quinone functionalization with a collection of O, N, and S nucleophiles, using oxygen as the terminal oxidant. Preliminary mechanistic observations and the first synthesis of the cytotoxic natural product strongylophorine‐26 is presented. 相似文献
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The theory of positive real functions is used to provide bounds for the largest possible disk to be inscribed in the stability region of an explicit Runge-Kutta method. In particular, we show that the closed disk |+r| r can be contained in the stability region of an explicitm-stage Runge-Kutta method of order two if and only ifr m – 1. 相似文献
99.
Malavika A. Bhide Kristian L. Mears Claire J. Carmalt Caroline E. Knapp 《Chemical science》2021,12(25):8822
Ethyl and amide zinc thioureides [L1ZnEt]2 (1), [L1*ZnEt]2 (2) and [L1Zn(N(SiMe3)2)]2 (3) have been synthesised from the equimolar reaction of thiourea ligands (HL1 = iPrN(H)CSNMe2 and HL1* = PhN(H)CSNMe2) with diethyl zinc and zinc bis[bis(trimethylsilyl)amide] respectively. New routes towards heteroleptic complexes have been investigated through reactions of 1, 2 and 3 with β-ketoiminates (HL2 = [(Me)CN(H){iPr}–CHC(Me) O]), bulky aryl substituted β-diiminates (HL3 = [(Me)CN(H){Dipp}–CHC(Me) N{Dipp}] (Dipp = diisopropylphenyl) and HL3* = [(Me)CN(H){Dep}–CHC(Me) N{Dep}] (Dep = diethylphenyl)) and donor-functionalised alcohols (HL4 = Et2N(CH2)3OH and HL4* = Me2N(CH2)3OH) and have led to the formation of the heteroleptic complexes [L1*ZnL3*] (5), [L1ZnL4]2 (6), [L1ZnL4*]2 (7), [L1*ZnL4] (8) and [L1*ZnL4*] (9). All complexes have been characterised by 1H and 13C NMR, elemental analysis, and the X-ray structures of HL1*, 1, 2, 6 and 7 have been determined via single crystal X-ray diffraction. Variable temperature 1H, COSY and NOESY NMR experiments investigating the dynamic behaviour of 5, 6 and 7 have shown these molecules to be fluxional. On the basis of solution state fluxionality and thermogravimetric analysis (TGA), alkoxyzinc thioureides 6 and 7 were investigated as single-source precursors for the deposition of the ternary material zinc oxysulfide, Zn(O,S), a buffer layer used in thin film photovoltaic devices. The aerosol-assisted chemical vapour deposition (AACVD) reaction of 7 at 400 °C led to the deposition of the heterodichalcogenide material Zn(O,S), which was confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray analysis (EDX), with optical properties investigated using UV/vis spectroscopy, and surface morphology and film thickness examined using scanning electron microscopy (SEM).This work investigates the synthesis and solution dynamics of heteroleptic alkoxyzinc thioureides for the chemical vapour deposition of the heterochalcogenide material Zn(O,S). 相似文献
100.
Sylvester-Hvid KO Mikkelsen KV Nymand TM Astrand PO 《The journal of physical chemistry. A》2005,109(5):905-914
We present a combined molecular dynamics/quantum chemical perturbation method for calculating the refractive index of liquid water at different temperatures. We compare results of this method with the refractive index obtained from other solvent models. The best agreement with the experimental refractive index of liquid water and its temperature dependence is obtained using correlated gas-phase polarizabilities in the classical Lorentz-Lorenz expression. Also, the iterative self-consistent reaction field approach in the semicontinuum implementation matches the experimental refractive index reasonably well. 相似文献