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11.
We construct two d-dimensional independent diffusions , with the same viscosity ν≠0 and the same drift u(x,t)=(pρta(x)v1+(1?p)ρtb(x)v2)/(pρta(x)+(1?p)ρtb(x)), where ρta,ρtb are respectively the density of Xta and Xtb. Here and p∈(0,1) are given. We show that is the unique weak solution of the following pressureless gas system such that as t→0+. To cite this article: A. Dermoune, S. Filali, C. R. Acad. Sci. Paris, Ser. I 337 (2003). 相似文献
12.
Ahmed I. Khodair Mona A. Elsafi Siham A. Al‐Issa 《Journal of heterocyclic chemistry》2019,56(9):2358-2368
A series of 3‐substituted 2‐thioxo‐2,3‐dihydro‐1H‐benzo[g]quinazolin‐4‐ones 4a – e were synthesized from the reaction of 3‐aminonaphthalene‐2‐carboxylic acid 1 with isothiocyanate derivatives 2a – e . The alkylation of 4a – e with alkyl halides gave 3‐substituted 2‐alkylsulfanyl‐2,3‐dihydro‐1H‐benzo[g]quinazolin‐4‐ones 5a – o . S‐Glycosylation was carried out via the reaction of 4a – e with glycopyranosyl bromides 7a and 7b under anhydrous alkaline conditions. The structure of the compounds was established as S‐nucleoside and not N‐nucleoside. Conformational analysis has been studied by homonuclear and heteronuclear two‐dimensional NMR methods (2D DFQ‐COSY, heteronuclear multiple quantum coherence, and heteronuclear multiple bond correlation). The S site of alkylation and glycosylation was determined from the 1H and 13C heteronuclear multiple quantum coherence experiments. 相似文献
13.
Assia Siham Hadj Hamou Khaled Elmiloudi Said Djadoun 《Journal of Polymer Science.Polymer Physics》2009,47(21):2074-2082
In a first step of this contribution, the observed glass transition temperature‐composition behavior of miscible blends of poly(styrene‐co‐N,N‐dimethylacrylamide) (SAD17) containing 17 mol % of N,N‐dimethylacrylamide and poly(styrene‐co‐acrylic acid) (SAA18, SAA27, and SAA32) containing increasing acrylic acid content, are analyzed according to theoretical approaches. Both Kwei and Brostow equations describe well the experimental data though better fits were obtained with the Brostow's approach. The specific interactions involved in these systems are a combination of intra and interassociation hydrogen bonding. The positive deviation from the linear mixing rule of Tg‐composition observed within the SAA18+SAD17 blend system, indicates that interassociation interactions are prevailing. More pronounced intra‐association interactions within the SAA32+SAD17 blend system led to a large negative deviation while a fine balance is established between these two types of interactions within the SAA27+SAD17 blend. A thermodynamic analysis was carried out according to the Painter‐Coleman association model. The miscibility and phase behavior of SAD17+SAA18 and SAD17+SAA27 blends are well predicted. However, this model predicts a partial miscibility of SAD17+SAA32 system. Finally, the fitting parameter free method developed by Coleman to predict the Tg‐composition behavior is applied. This method predicts fairly well the evolution trend of experimental Tgs of the SAA18+SAD17 and SAA27+SAD17 blend systems. However, the compositional dependence of SAA32+SAD17 blend Tg was not predictable by this method. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47:2074–2082, 2009 相似文献
14.
Siham?Difi Ismael?Saadoune Moulay?Tahar?Sougrati Rachid?Hakkou Kristina?Edstrom Pierre-Emmanuel?LippensEmail author 《Hyperfine Interactions》2016,237(1):61
The role of iron in Na 1.5Fe 0.5Ti 1.5(PO 4)3/C electrode material for Na batteries has been studied by 57Fe Mössbauer spectroscopy in operando mode. The potential profile obtained in the galvanostatic regime shows three plateaus at different voltages due to different reaction mechanisms. Two of them, at 2.2 and 0.3 V vs Na +/Na 0, have been associated to redox processes involving iron and titanium in Na 1.5Fe 0.5Ti 1.5(PO 4)3. The role of titanium was previously elucidated for NaTi 2(PO 4)3 and the effect of the substitution of Fe for Ti was investigated with 57Fe Mössbauer spectroscopy. We show that iron is an electrochemically active center at 2.2 V with the reversible Fe 3+/Fe 2+ transformation and then remains at the oxidation state Fe 2+ along the sodiation until the end of discharge at 0 V. 相似文献
15.
Michael Schwall Leslie M. Schoop Siham Ouardi Benjamin Balke Claudia Felser Peter Klaer Hans‐Joachim Elmers 《Advanced functional materials》2012,22(9):1822-1826
A thermodynamically stable phase separation of Co2Dy0.5Mn0.5Sn into the Heusler compound Co2MnSn and Co8Dy3Sn4 is induced by rapid cooling from the liquid phase. The phase separation forms an ordered flower‐like structure on the microscale. The increased scattering of phonons at the phase boundaries reduces the thermal conductivity and thus improves thermoelectric and spincaloric properties. 相似文献
16.
Mohamed A. A. Radwan Marwa A. Shehab Siham M. El-Shenawy 《Monatshefte für Chemie / Chemical Monthly》2009,140(4):445-450
Abstract 5-Aminobenzo[b]thiophene-2-carboxylic acid was converted to the corresponding 5-(2-chloroacetamido)benzo[b]thiophene-2-carboxylic acid by reaction with chloroacetyl chloride. This acetamido product was treated with different alkyl,
cycloalkyl, aryl, and heterocyclic amines to afford a series of C5-substituted benzo[b]thiophenes. These compounds were found to possess potent anti-inflammatory activity.
Graphical abstract
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17.
Shakya Anshul Chikhale Rupesh V. Bhat Hans Raj Alasmary Fatmah Ali Almutairi Tahani Mazyad Ghosh Surajit Kumar Alhajri Hassna Mohammed Alissa Siham A. Nagar Shuchi Islam Md Ataul 《Molecular diversity》2022,26(1):265-278
Molecular Diversity - Transmembrane protease serine-2 (TMPRSS2) is a cell-surface protein expressed by epithelial cells of specific tissues including those in the aerodigestive tract. It helps the... 相似文献
18.
Ouardi S Fecher GH Kozina X Stryganyuk G Balke B Felser C Ikenaga E Sugiyama T Kawamura N Suzuki M Kobayashi K 《Physical review letters》2011,107(3):036402
This study reports on the linear dichroism in angular-resolved photoemission from the valence band of the Heusler compounds NiTi0.9Sc0.1Sn and NiMnSb. High-resolution photoelectron spectroscopy was performed with an excitation energy of hν = 7.938 keV. The linear polarization of the photons was changed using an in-vacuum diamond phase retarder. The valence band spectra exhibit the typical structure expected from first-principles calculations of the electronic structure of these compounds. Noticeable linear dichroism is found in the valence band of both materials, and this allows for a symmetry analysis of the contributing states. The differences in the spectra are found to be caused by symmetry-dependent angular asymmetry parameters, and these occur even in polycrystalline samples without preferential crystallographic orientation. 相似文献
19.
Siham Benkouda Mounir Amir Tarek Fortaki Abdelmadjid Benghalia 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(11):1350-1366
The dual-frequency behavior of stacked high T
c
superconducting rectangular microstrip patches fabricated on a two-layered substrate is investigated using a full-wave spectral
analysis in conjunction with the complex resistive boundary condition. Using a matrix representation of each layer, the dyadic
Green’s functions of the problem are efficiently determined in the vector Fourier transform domain. The stationary phase method
is used for computing the radiation electric field of the antenna. The proposed approach is validated by comparison of the
computed results with previously published data. Variations of the lower and upper resonant frequencies, bandwidth and quality
factor with the operating temperature are given. Results showing the effects of the bottom patch thickness as well as the
top patch thickness on the dual-frequency behavior of the stacked configuration are also presented and discussed. Finally,
for a better comprehension of the dual-frequency operation, a comparison between the characteristics of the lower and upper
resonances is given. 相似文献
20.
Alqaradawi SY Bazzi HS Mostafa A Nour el-M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(4):1594-1598
The solid charge-transfer complexes formed in the reaction of the electron donor 1,4,7-trimethyl-1,4,7-triazacyclononane (TMTACN) with the acceptors iodine, tetracyanoethylene (TCNE) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) have been isolated. These were characterized through electronic and infrared spectra as well as thermal and elemental analysis. The results show that the formed solid CT-complexes have the formulas [(TMTACN)I]I3, [(TMTACN)(TCNE)5] and [(TMTACN)(TCNQ)3] in full agreement with the known reaction stoichiometries in solution. The chloranil CT-solid complex cannot be isolated in pure form. 相似文献