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1.
Huazhong Tang Tao Tang Kun Xu 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,55(3):365-382
In this paper, the Kinetic Flux Vector Splitting (KFVS)
scheme is extended to solving the shallow water equations with
source terms. To develop a well-balanced scheme between the source
term and the flow convection, the source term effect is accounted
in the flux evaluation across cell interfaces. This leads to a
modified gas-kinetic scheme with particular application to the
shallow water equations with bottom topography. Numerical
experiments show better resolution of the unsteady solution than
conventional finite difference method and KFVS method with little
additional cost. Moreover, some positivity properties of the
gas-kinetic scheme is established. 相似文献
2.
较为详细地介绍AT91SAM7S64芯片的I2C接口控制器中外围数据控制器(PDC)的使用方式,并将其与AT24C04之间的通信作为实例给出完整的应用开发流程和软硬件详细描述。该方法的可行性已经为工程实践和实际产品所证实。该操作也可推广到其他AT91SAM7S系列ARM处理器与其他I2C接口器件间的通信。并对其他拥有外围数据控制器的接口开发有一定的借鉴意义。 相似文献
3.
E. M. Afsah M. M. Abou-Elzahab M. T. Zimaity G. R. Proctor 《Monatshefte für Chemie / Chemical Monthly》1984,115(8-9):1065-1070
When -keto-ester1 a was reacted with dimethyl acetylenedicarboxylate ring expansion occurred to give substituted cyclooctadienones.Michael reactions of the title compounds1 with unsaturated ketones gave adducts, some of which underwent further cyclization reactions. A new route to -tetralone ring system10 via cyclization of the intermediateMichael adduct9 is described.
Michael- und Ringerweiterungsreaktionen von 6-Carboethoxy-3,5-diaryl-2-cyclohexen-1-onen
Zusammenfassung Bei der Reaktion von -Keto-ester1 a mit Dimethyl-acetylendicarboxylat wurden unter Ringerweiterung substituierte Cyclooctadienone erhalten. DieMichael-Reaktion der Titelverbindung1 mit ungesättigten Ketonen ergab Addukte, von denen einige weitere Cyclisierungsreaktionen eingingen. Es wird ein neuer Weg zum -Tetralonsystem10 über die Cyclisierung des intermediärenMichael-Addukts9 beschrieben.相似文献
4.
-(2-Arylaminoethoxy)styrenes undergo cyclization in the presence of KOH to giveN-aryl-2-benzyloxazolidines inca. 90 % yield. The structures of the products were confirmed by IR and NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 340–341, February, 1994. 相似文献
5.
V. Ramamoorthy A. Ramasubbu S. Muthusubramanian S. Sivasubramanian 《Journal of inclusion phenomena and macrocyclic chemistry》1999,33(1):69-80
The nitrone is found to be included in the -cyclodextrin cavity in two different stoichiometries viz., 1G : 1H and 1G : 2H – the existence of which is proved by physical methods. The 1G : 2H complex of the nitrone serves as a good potent dipolarophile in the 1,3-dipolar cycloaddition reactions with olefins resulting in rate acceleration and regioselection. 相似文献
6.
We investigate then limit of then-vector model single-spin and pairspin correlation functions. In this limit we show that the correlation functions become those of the corresponding spherical model. 相似文献
7.
R. F. Klevtsova L. A. Glinskaya T. E. Kokina S. V. Larionov 《Journal of Structural Chemistry》2003,44(2):256-267
Single crystals of [Ni(Phen)(iBu2PS2)2] (I) and [Ni(Phen)3](iBu2PS2)2 (III) compounds were grown, and their structures were determined by Xray diffraction analysis (CAD4 diffractometer, MoK
radiation, 3336 F
hkl
, R = 0.0373 for I and 2575 F
hkl
for III). The crystals of complex I have a triclinic unit cell with the following parameters: a = 11.097(1) , b = 14.903(2) , c = 22.650(3); = 75.18(1)°, = 80.50(1)°, = 75.07(1)°, V = 3479.2(7)3, Z = 4, calc = 1.255 g/cm3, and space group
1; the crystals of III have a monoclinic unit cell with the following parameters: a = 19.010(3), b = 15.481(1) , c = 17.940(3); = 97.58(1)°, V = 5233.5(12)3, Z = 4, calc = 1.292 g/cm3, and space group C2/c. The structure of complex I is built from mononuclear molecules, and the structure of III, from [Ni(Phen)3]2+ complex cations and i Bu2PS2
- outersphere anions. The NiN2S4 coordination polyhedra in the structure of I and NiN6 in the structure of III are distorted octahedra. Based on structural data, the interaction between the coordinated Phen molecules of complexes I, [Ni(Phen)2(iBu2PS2)](iBu2PS2) (II), and III is considered, as well as the packing modes of these complexes. 相似文献
8.
A. L. Rusanov G. S. Matvelashvili G. V. Kazakova M. L. Keshtov A. K. Mikitaev 《Russian Chemical Bulletin》1996,45(3):633-636
Synthesis of 4,4-bis(4-aminophenoxy)benzophenone was performed starting from chloral. Various polyimides were obtained by reactions of 4,4 -bis(4-aminophenoxy)benzophenone with aromatic tetracarboxylic acid dianhydrides. Some of the polyimides obtained are crystalline compounds.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 673–676, March, 1996. 相似文献
9.
J. Rätz 《Aequationes Mathematicae》1976,14(1-2):67-71
LetK be a ring with an identity 1 0 andM, L two unitaryK-modules. Then, for any additive mappingf:M L, the setH
f
:={ K f(x)=f(x) for allx M} forms a subring ofK, the homogeneity ring off. It is shown that, forM {0},L {0} and any subringS ofK for whichM is a freeS-module, there exists an additive mappingf:ML such thatH
f
=S. This result is applied to the four Cauchy functional equations, and it leads also to an answer to the question as to whether it is possible to introduce onM a multiplication ·:M × M M makingM into a ring but not into aK-algebra. 相似文献
10.
遥感杂波的模拟广泛应用于遥感成像、电子对抗等相关领域.文章使用TMS320C64x DSP处理器根据实时侦察获取的遥感参数进行实时杂波信号的仿真生成,与理论数据比较有较大相关性. 相似文献