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排序方式: 共有194条查询结果,搜索用时 31 毫秒
61.
In this paper, we present a combination method of constructing the
explicit and exact solutions of nonlinear partial differential
equations. And as an illustrative example, we apply the method to
the Benney-Kawahara-Lin equation and derive its many explicit and
exact solutions which are all new solutions. 相似文献
62.
Solving mKdV-sinh-Gordon equation by a modified variable separated ordinary differential equation method
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By introducing a more general auxiliary ordinary differential equation (ODE), a modified
variable separated ODE method is
developed for solving the mKdV--sinh-Gordon equation. As a result,
many explicit and exact solutions including some new formal
solutions are successfully picked up for the mKdV--sinh-Gordon
equation by this approach. 相似文献
63.
OV-17负载交联β-环糊精聚合物毛细管柱的研制 总被引:6,自引:0,他引:6
合成了一种非水溶性交联 β 环糊精聚合物。环糊精聚合物在异丙醚、二氯甲烷和苯的混合溶剂中 ,经超声波处理 0 5h ,配成质量浓度为 2 6g/L的溶胶状固定液 ,并采用超动态法成功地将其涂渍到弹性石英毛细管柱上。该毛细管柱柱效高达 30 0 0·m- 1 ,热稳定性好 ,属中等极性。对二甲苯和二氯苯芳香位置异构体及α 蒎烯、β 蒎烯、乳酸乙酯、α 苯乙醇、1 ,2 丙二醇、α 紫萝酮、α 氯代丙酸甲酯、γ 戊内酯等对映体进行了色谱分离。实验表明 ,经超声波处理过的非水溶性交联 β 环糊精聚合物适合作毛细管气相色谱固定相。 相似文献
64.
Velikorodov A. V. Poddubnyi O. Yu. Ionova V. A. Titova O. L. 《Russian Journal of Organic Chemistry》2011,47(10):1596-1597
Russian Journal of Organic Chemistry - 相似文献
65.
余德民 《纯粹数学与应用数学》2014,30(4):341-346
构造了一类无限维李代数,它是Virasoro-like李代数的推广.研究了这类李代数的两类自同构,这两类自同构均关于映射的合成构成自同构群,一类同构于对称群S3,另一类同构于Klein交换群.得到了这类李代数一些特殊的自同态、中心.证明了这类李代数不是半单李代数. 相似文献
66.
The rapid expansion of a supercritical solution (RESS) process represents an attractive prospect for producing sub-micron and nano-particles of medical compounds with low solubility. The solubility of phenacetin in supercritical carbon dioxide was measured by the analytical-isothermal method at pressures ranging from 9.0 MPa to 30.0 MPa and temperatures ranging from 308.0 K to 328.0 K. The results show that the mole fraction solubility of phenacetin in supercritical carbon dioxide is up to 10?5. Four density-based semi-empirical models were introduced to correlate the experimental data. Agreement between the model predictions and experimental data is greater with the Adachi-Lu-modified Chrastil model than with the Chrastil model, Méndez-Santiago-Teja model, and the Bartle model and the average absolute relative deviation (AARD) observed is 0.0483. The preparation of fine phenacetin particles by the RESS process under different conditions of extraction temperatures (308.0–328.0 K), extraction pressures (9.0–30.0 MPa), nozzle temperatures (373.0–393.0 K), nozzle diameters (0.1–0.8 mm), and collection distance (20.0–40.0 mm) was investigated. The size and morphology of the resultant particles were analysed by SEM. A remarkable modification in size and morphology can be obtained by condition-optimisation. 相似文献
67.
Ping Xu Xinyu Jiang Congshan Zhou Kewen Tang 《Journal of inclusion phenomena and macrocyclic chemistry》2013,77(1-4):447-453
The inclusion interaction between hydroxypropyl-β-cyclodextrin (HP-β-CD) and hydrophilic 2-chloromandelic acid (CMA) was studied by ultraviolet (UV) absorption spectrophotometer. A reliable determination of the complex stoichiometry was provided by the continuous variation technique. 1H NMR spectrum and Thermo-gravimetric/differential thermal analyzer (TG/DTA) techniques were explored to further characterize the inclusion complex, and molecular modeling was used to investigate the mechanism of inclusion interaction. The results showed that HP-β-CD reacted with R,S-CMA to form inclusion complexes, with 1:1 stoichiometry and inclusion stability constants KR and KS were 24 and 39 L/mol determined from UV data by the method of Benesi-Hildebrand’s. Molecular modeling confirmed experimental observation and indicated that the hydrogen bonding interaction plays an important role in the interactive inclusion between HP-β-CD and CMA. Besides, compared with the HP-β-CD, molecular modeling showed R, S-CMA interact with β-CD through different binding modes, in which Vander Waals is the main intermolecular force between β-CD and R-CMA (or S-CMA) while without obvious hydrogen bonding interaction. 相似文献
68.
The title compound 4-chloro-2-(morpholine-4-carbonyl)phenyl-4'-methoxybenzoate(C19H18ClNO5, Mr = 375.79), a 5-chlorosalicylic acid derivative incorporating morpholine moiety, was conveniently synthesized through two steps and crystallized in the monoclinic space group P21/c with a = 7.8501(10), b = 9.3149(12), c = 25.133(3), V = 1836.2(4)3, Z = 4, Dc = 1.359 Mg/m3, λ = 0.71073, μ(MoKα) = 0.237 mm-1, F(000) = 784, R = 0.0447 and wR = 0.1227 for 3982 independent reflections with I 2σ(I). The dihedral angles formed between 4-methoxybenzene and 5-chlorobenzene rings, the 5-chlorobenzene and morpholine, and 4-methoxybenzene and morpholine rings are 82.55(3), 72.56(5) and 47.68(0)° by X-ray analysis, respectively. Bioassay shows that the title compound has a good molluscidal effect. 相似文献
69.
Velikorodov A. V. Kutlalieva E. N. Stepkina N. N. Shustova E. A. Poddubny O. Yu. 《Russian Journal of Organic Chemistry》2020,56(9):1570-1575
Russian Journal of Organic Chemistry - Electrophilic amination of methyl N-(hydroxyphenyl)carbamates and methyl N-(4-methoxyphenyl)carbamate with sodium azide in 86% polyphosphoric acid (PPA) at... 相似文献
70.
M. A. Abdelrakhim A. G. Tyrkov E. A. Yurtaeva 《Russian Journal of Organic Chemistry》2014,50(2):280-284
A procedure of synthesis of 2-(2-methyltetrazol-5-yl)-2,2-dinitroacetonitrile has been developed and its reaction with substituted nitrile N-oxides has been investigated, proceeding by the mechanism of 1,3-dipolar cycloaddition and affording 2-methyl-5-[(1,2,4-oxadiazol-5-yl)(dinitro)methyl]-2H-tetrazoles. The latter react with KOH in ethanol forming the potassium salt of 2-methyltetrazol-5-yldinitromethane and substituted 5-hydroxy-1,2,4-oxadiazoles. 相似文献