全文获取类型
收费全文 | 111篇 |
免费 | 2篇 |
国内免费 | 8篇 |
学科分类
数理化 | 121篇 |
出版年
2023年 | 1篇 |
2019年 | 1篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 6篇 |
2009年 | 3篇 |
2008年 | 12篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 4篇 |
2003年 | 3篇 |
2002年 | 5篇 |
2001年 | 14篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
排序方式: 共有121条查询结果,搜索用时 46 毫秒
1.
较详细地讨论了附加压力与分散系统稳定性间的关系,指出分散相附加压力的降低是分散系统趋向稳定的根本原因。以乳状液为例,附加压力降低不仅减少了液滴间相互碰撞的概率,而且更重要的是,它与液滴表面形成牢固的保护膜密切相关。只有当液滴的附加压力趋近0时,分散系统才达到热力学上稳定的状态,此时乳状液已变成了微乳状液。上述讨论也基本适用于固/液分散系统。 相似文献
2.
Technical properties of two naphthalimide based disperse dyes on nylon 6 and polyester fibers were investigated in the presence of urea.The two naphthalimide based disperse dyes were synthesized.The dyes were purified and then fully characterized using ~1H-NMR,FTIR and melting point analysis.Dispersion of the dyes was prepared in water and applied on nylon 6 and PET fibers.The dyes offered good build-up properties on the substrates.In order to increase dye adsorption of the substrates,urea was added into... 相似文献
3.
A non-linear optical(NLO) material was synthesized by means of a simple method. This material can be applied in electro-optical(EO) devices, such as EO switches and modulators. The Disperse Red 1(DR1) was doped in polymethyl-methacrylate-co-glycidyl methacrylate(PMMA-co-GMA) as the NLO active chromophore. The synthesis process and material structure were expressed. The thermal properties, surface morphology and optical characteristics of the material were investigated by means of differential scanning calorimetry(DSC), thermogravimetric analysis (TGA), atomic force microscopy(AFM), and m-lines technique. Using the reflection technique, the value of the electro-optical coefficient γ33 was measured as 11 pm/V at a wavelength of 1310 nm. An EO switch with nanosecond response based on this material has been fabricated. 相似文献
4.
Tawfik A. Khattab Karima M. Haggag Mohamed H. Elnagdi Amal A. Abdelrahman Sherif Abdelmoez Aly 《无机化学与普通化学杂志》2016,642(13):766-772
The synthesis of heterocyclic azo‐dyes via conventional heating and microwave (MW) heating was investigated. From a sequence of reactions starting from cyanoacetic acid, 4‐arylazo‐2H‐pyrazol‐3‐ylamines and 4‐arylazo‐2‐phenyl‐2H‐pyrazol‐3‐ylamines were obtained. The structures these compounds were obtained by inspection of spectroscopic and analytical techniques including 1H and 13C NMR spectroscopy, IR spectroscopy, mass spectrometry, and elemental analysis. The fastness properties and UV/Vis absorption spectroscopic data of these disperse dyes in printing polyester fabrics were investigated. 相似文献
5.
Summary The aggregation behaviour of zinc-free insulin has been studied by small-angle neutron scattering as a function of protein
concentration,pH, and ionic strength of the solution. The distance distribution functions for the 12 samples have been obtained by indirect
Fourier transformation. The weight-averaged molecular mass and thez-averaged radius of gyration were determined. Both quantities vary systematically with the experimental conditions. They increase
with decreasingpH and with increasing ionic strength. The radius of gyration scales as a power law of the weight-average mass with the exponent
0.44. A similar scaling is found for a set of oligomers structures based on the crystal structure of zinc-free insulin. The
mass distribution between the oligomers was determined by a model based on these oligomers. The results from this model and
the Fourier transformations have been compared to an equilibrium model recently introduced by Kadimaet al. The model takes into account the variation of the effective charge of the monomer withpH and ionic strength. The neutron scattering results agree well with the predictions of the model.
Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994. 相似文献
6.
P. B. Warren 《Il Nuovo Cimento D》1994,16(8):1231-1236
Summary The scaling of the ratio of the hydrodynamic radius to the radius of gyration of fractal aggregates is probed by numerical
simulations for several different algorithms. In common with previous work it is found that this ratio shows a significant
and long-lasting finite-size effect for particle-cluster aggregates, but a much less significant finite-size effect for hierarchical
cluster-cluster aggregates. Simple theoretical models which reproduce the behaviour are discussed.
Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994. 相似文献
7.
Discrete simulation methods are efficient tools to investigate the behaviors of complex fluids such as dry granular materials
or dilute suspensions of hard particles. By contrast, materials made of soft and/or concentrated units (emulsions, foams,
vesicles, dense suspensions) can exhibit both significant elastic particle deflections (Hertz-like response) and strong viscous
forces (squeezed liquid). We point out that the gap between two particles is then not determined solely by the positions of
their centers, but rather exhibits its own dynamics. We provide the first ingredients of a new discrete numerical method,
named Soft Dynamics, to simulate the combined dynamics of particles and contacts. As an illustration, we present the results for the approach
of two particles. We recover the scaling behaviors expected in three limits: the Stokes limit for very large gaps, the Poiseuille-lubricated limit for small gaps and even smaller surface deflections, and the Hertz limit for significant surface deflections. We find that for each gap value, an optimal force achieves the fastest approach
velocity. The principle of larger-scale simulations with this new method is provided. They will consitute a promising tool
for investigating the collective behaviors of many complex materials. 相似文献
8.
Roger M Guenoun P Muller F Belloni L Delsanti M 《The European physical journal. E, Soft matter》2002,9(4):313-326
The concentration profiles of monomers and counterions in star-branched polyelectrolyte micelles are calculated through Monte
Carlo simulations, using the freely jointed chain model. We have investigated the onset of different regimes corresponding
to the spherical and Manning condensation of counterions as a function of the strength of the Coulomb coupling. The Monte
Carlo results are in fair agreement with the predictions of Self-Consistent-Field analytical models. We have simulated a real
system of diblock copolymer micelles of (sodium-polystyrene-sulfonate)(NaPSS)-(polyethylene-propylene)(PEP) with f = 54 hydrophilic branches of N = 251 monomers at room temperature in salt-free solution. The calculated form factor compares nicely with our neutron scattering
data.
Received 18 July 2002 and Received in final form 11 October 2002
RID="a"
ID="a"e-mail: roger@drecam.saclay.cea.fr 相似文献
9.
Kamaladin Gharanjig Mokhtar Arami Shohre Rouhani Hajir Bahrami Barahman Movassagh Niyaz Mohammad Mahmoodi 《中国化学会会志》2007,54(4):1021-1028
Five novel monoazo disperse dyestuffs based on N‐ester‐1,8‐naphthalimide were synthesized. Acenaphthene was nitrated, then oxidized to 4‐nitro‐1,8‐naphthalic anhydride. 4‐Nitro‐1,8‐naphthalic anhydride was reacted with methyl and ethyl glycinate in alcoholic media, followed with reduction. 4‐Amino‐N‐methyl and ethyl glycinate‐1,8‐naphthalimide were obtained. These products were diazotized and coupled with appropriate aromatic amines to give bluish‐red or violet dyestuffs. All intermediates and dyestuffs were purified and characterized by 1H‐NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Dispersion of dyestuffs was prepared in water and applied to polyester fabrics. The dyed fabrics showed that four of the synthesized dyestuffs were suitable for coloring polyester fibers, producing deep bluish red with very good build up properties. 相似文献
10.
We demonstrate that ferroelectric liquid crystals dispersed in a polymer matrix can form uniaxially aligned elliptical droplets. The alignment is controlled by mechanical shear during the polymerization of a UV-curable adhesive. The possibility of prealignment makes polymer-dispersed ferroelectric liquid crystals suitable for application in flexible electro-optical displays. In contrast to surface stabilized ferroelectric liquid crystal displays, the electro-optical effect in our system is due to the deformed-helix ferroelectric (DHF) effect. 相似文献