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11.
Weixiong Wang Daniel De Kee Damir Khismatullin 《ournal of non Newtonian Fluid Mechanics》2011,166(12-13):734-744
In our previous report, we showed that a rheometer equipped with a double concentric cylinder geometry with slotted rotor could effectively reduce wall slip effects and thus it could be used as an alternative to a rheometer with a vane geometry in yield stress measurements. Here, we use three-dimensional CFD simulation to compare these two geometries for rheological measurements of power law and yield stress fluids. Our results indicate that the double concentric cylinder rheometer with slotted rotor (DCCR/SR) is able to accurately measure rheological properties of a wider spectrum of test fluids than a vane rheometer because of significant reduction of the end and secondary flow effects. 相似文献
12.
Damir I. Sagdeev Marina G. Fomina Ilmutdin M. Abdulagatov 《Journal of solution chemistry》2017,46(4):966-988
The density and viscosity of a ternary 1-hexene(1) + 1-octene(2) +1-decene(3) mixture (\( w_{1} = w_{2} = w_{3} = 0.333 \) weight fractions or \( x_{1} = 0.4257 \),\( x_{2} = 0.3190 \), \( x_{3} = 0.2553 \) mole fractions of 1-hexene, 1-octene, and 1-decene, respectively) have been simultaneously measured over the temperature range from (298 to 471) K and at pressures up to 196 MPa using a combined method of hydrostatic weighing and falling-body techniques, respectively. The combined expanded uncertainties of the density, pressure, temperature, concentration, and viscosity measurements at the 95% confidence level with a coverage factor of k = 2 are estimated to be (0.15 to 0.30)%, 0.05%, 0.02 K, 0.005 mol%, and (1.5 to 2.0)%, respectively. The measured densities and viscosities were used to calculate the excess molar volumes and viscosity differences. The excess molar properties (\( G_{\text{m}}^{\text{E}} , \, H_{\text{m}}^{\text{E}} , \, S_{\text{m}}^{\text{E}} \) and \( C_{\text{pm}}^{\text{E}} \)) and their pressure derivatives as a function of temperature and pressure have been calculated using the derived excess molar volumes. The measured viscosities were used to develop a theoretically based viscosity correlation model (Arrhenius–Andrade type equation) for the mixture. 相似文献
13.
Damir A. Safin Maria G. Babashkina Axel Klein Heinrich Nöth Michael Bolte Dmitriy B. Krivolapov 《Polyhedron》2010
Reaction of the potassium salt of N-(diisopropoxyphosphoryl)-p-bromothiobenzamide p-BrC6H4C(S)NHP(O)(OiPr)2 (HL) with Cd(II) cations in freshly dried and distilled EtOH leads exclusively to the complex [Cd(p-BrC6H4C(S)NH2-S)(L-O,S)2] ([Cd(LI)L2]), while the same reaction in H2O leads to the complex [Cd(HL-O)2(L-O,S)2] ([Cd(HL)2L2]). The corresponding reactions with Zn(II) always lead to the complex [Zn(L-O,S)2] ([ZnL2]) regardless of the solvent. The crystal structure of [Cd(HL)2L2].2/3H2O reveals to be a polymorph to the previously reported anhydrous [Cd(HL)2L2]. 相似文献
14.
15.
The halogen/lithium (X/Li) exchange’s usefulness is challenged by the extreme conditions employed during the conversion of a bromo or an iodo substituent to an organolithium intermediate. Our preliminary disclosure reveals that simple X/Li exchanges can be accomplished at ambient temperature and in doped hydrocarbon media using n-BuLi. Use of a continuous reactor featuring brief reaction times (?1 s) and large product throughputs further facilitates the production of a product resulting from a sequential X/Li exchange and nucleophilic addition. 相似文献
16.
We give new bounds and asymptotic estimates on the largest Kronecker and induced multiplicities of finite groups. The results apply to large simple groups of Lie type and other groups with few conjugacy classes. 相似文献
17.
ABSTRACT 6-Amino coumarin has been established as an efficient nitrite ion selective fluorescent sensor. The developed method shows linearity up to 1.6 × 10?6 mol L?1 of nitrite ion concentration. Interference from other common anions is almost negligible. The reagent shows strong binding affinity towards nitrite ion as evident from its binding constant value (5.8 × 104), estimated by Stern-Volmer method. Some real samples were analyzed. Single crystal X-ray structure of the reagent is reported. Preliminary computational studies on the molecular level interaction between the reagent and nitrite ion were performed by density functional theory (DFT, B3LYP) method. 相似文献
18.
G. Baroni S.Di. Liberto F. Meddi S. Petrera G. Romano M. Juric O. Adamovic I. Otterlund G. Baumann R. Devienne H. Areti C.J.D. Hebert J. Hebert J. Lory C. Meton D. Schune B. Willot G. Rey 《Nuclear Physics B》1976,103(2):213-220
The single- and two-particle inclusive rapidity distributions for proton-nucleus interactions at 300 GeV in nuclear emulsions are presented. The analysis of the data with the two-particle rapidity correlation function R(ν1, ν2) shows clear evidence of short range correlations. A remarkable asymmetry between projectile and target hemisphere is found. 相似文献
19.
Damir Kinzebulatov 《Potential Analysis》2018,48(2):207-222
We construct a L p -strong Feller process associated with the formal differential operator ? Δ + σ ?? on \(\mathbb R^{d}\), \(d \geqslant 3\), with drift σ in a wide class of measures (e.g. the sum of a measure having density in weak L d space and a Kato class measure), by exploiting a quantitative dependence of the smoothness of the domain of an operator realization of ? Δ + σ ?? generating a holomorphic C 0-semigroup on \(L^{p}(\mathbb R^{d})\), p > d ? 1, on the value of the relative bound of σ. 相似文献
20.
Annika Arndt Damir Posavec Stefan Schwarzer Mathias S. Wickleder Prof. Dr. 《无机化学与普通化学杂志》2008,634(3):431-435
The reaction of the nitrates M(NO3)3·6H2O (M = La, Pr) and (H3O)2PtCl6 led to yellow single crystals of [M(NO3)2(H2O)6]2[PtCl6]·2H2O (M = La, Pr) (monoclinic, P21/c, Z = 2, La/Pr: a = 697.4(3)/695.5(1), b = 1654.5(1)/1652.5(2), c = 1317.7(6)/1318.5(3) pm, β = 93.97°(7)/93.93°(2), Rall = 0.0169/0.0659) while the reaction of M(NO3)3·5H2O (M = Gd, Dy) and (H3O)2PtCl6 yielded yellow single crystals of [M(NO3)(H2O)7][PtCl6]·4H2O (monoclinic, P21/n, Z = 4, Gd/Dy: a = 838.72(3)/838.40(2), b = 2131.98(6)/2139.50(7), c = 1142.63(3)/1143.10(3) pm, β = 95.670(4)/95.698(3), Rall = 0.0475/0.0337). The crystal structures consist of octahedral [PtCl6]2? anions and complex [M(NO3)2(H2O)6]2+ and [M(NO3)(H2O)7]2+ cations, respectively. The thermal decomposition of both types of compounds leads via various steps to elemental platinum and the oxide chlorides MOCl (M = La, Pr, Gd, Dy). 相似文献