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In order to design thermal protection system, it is important to predict heat transfer rate precisely on the hypersonic vehicles. In present paper, considering chemical reaction, interal energy excitation and thermo-chemical non-equilibrium effects of high temperature air, the thermo-chemical non-equilibrium flow-fields are simulated using the numerical code AEROPH_Flow. An aero physical numerical code system for Hypersonic vehicles, the distributions of heat transfer rate is obtained, and the analysis is done for the influence of the chemical reaction model, thermodynamic non-equilibrium model, surface temperature, surface material catalytic action on the computational results. The results show that thermo-chemical non-equilibrium models have a more important influence on the computational results, it is important for the selection of the correct air reaction model and thermal non equilibrium model according to the flight environment and thermo-chemical non-equilibrium mechanism of the flow field around the hypersonic vehicles; the heat transfer rate isn't always the highest for lower surface temperature, and it become very complicated for the variation law of heat transfer rate along with the surface temperature under the condition of high Mach number or thermo-chemical non-equilibrium flow, so the surface temperature may as well be fixed choosed according to the distribution of the real flight condition or different constant for computing exactly heat transfer rate on the hypersonic vehicles. [ABSTRACT FROM AUTHOR]

Blends of polystyrene (PS) and polypropylene (PP) were prepared through melt compounding. With an increase of PS content up to 30 wt%, the tensile strength of PP/PS blends increased from 37.4 MPa to 42.2 MPa, although the blends were widely regarded as immiscible. The DSC results showed that there's slight decrease in melting temperature of PP, showing insufficient evidence for partial compatibility between PP and PS. Almost no variation of distinct characterization peaks were observed in FTIR spectra of PS/PP blends compared with those of neat PP and PS, indicating there is no chemical interactions between PP and PS. Since the morphology investigation showed a droplet structure as PS content was up to 30 wt%, the improvement of tensile strength could be simply considered as due to the reinforcing effect of dispersed rigid PS particles on the PP, combining with partial compatibility between them as evaluated by change of C at glass transition for both PS and PP. More interestingly, DSC and DMA results showed that the blending of PS and PP could lead to a substantial decrease of the glass transition temperature ( T) of PP, and increase of T of PS. The annealing experiment was carried out to understand the change of T in PP/PS blends. It is believed that the compressive stress generated by the contracting PP should be the dominant mechanism for the T elevation of PS. On the other hand, the T decrease of PP is likely owing to the creation of a large amount free interface of PP and the dilatation of the PP phase resulting from the corresponding tension exerted by PS during cooling. [ABSTRACT FROM AUTHOR]

Ethyl 2-amino-4-methyl-5-(1H-1,2,4-triazol-1-yl)thiophene-3-carboxylate 2, obtained from Gewald reaction of 1-(1H-1,2,4-triazol-1-yl)acetone 1 with ethyl cyanoacetate and sulfur, was transferred into iminophosphorane 3. Further reaction of 3 with aromatic isocyanates gave carbodiimides 4, which were treated subsequently with a secondary amine to give 6-(1H-1,2,4-triazol-1-yl)-thieno[2,3-d]pyrimidin-4(3H)-ones 6 in good yields in the presence of a catalytic amount of sodium ethoxide. [ABSTRACT FROM AUTHOR]

Isothiocyanate 2, obtained from aza-Wittig reaction of iminophosphorane 1 with CS2, reacted with amine to give 2-thioxo-2,3,5,6,7,8-hexahydrobenzothieno[2,3-d]pyrimidin-4(1H)-ones 4 in the presence of sodium ethoxide. S-Alkylation of 4 produced 2-alkylthio-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidin-4(3H)-ones 5 in good yields. [ABSTRACT FROM AUTHOR]

The isothiocyanate 3, obtained from aza‐Wittig reaction of iminophosphorane 2 with CS2, reacts with phenylhydrazine to give thiosemicarbazide 4. Reactions of 4 with alkyl halides in the presence of K2CO3 directly provided 2‐alkylthio‐4H‐imidazol‐4‐ones 6 in good yields. [ABSTRACT FROM AUTHOR]

Double 2-alkylthio-5-phenylmethylidene-4H-imidazol-4-ones 6 were synthesized by S-alkylation of double 2-thioxo-5-phenylmethylidene-4-imidazolidinone 5, which was obtained via cyclization of vinyl isothiocyanate 4 with ethylenediamine. [ABSTRACT FROM AUTHOR]

The carbodiimides 2, obtained from aza–Wittig reactions of iminophosphorane 1 with aromatic isocyanates, reacted with aliphatic primary amines to give mainly 2-alkylamino-4(3H)-quinazolinones 4 with unusual selectivity. [ABSTRACT FROM AUTHOR]

2-Alkylthio-5-phenylmethylidene-4H-imidazolin-4-ones 5 were synthesized by S-alkylation of thioimidazolinones 4, which were obtained via cyclization of carbodiimides 2 with Na2S/HOAc. The direct reaction of carbodiimides 2 with butylthiol could not give 2-butylthio-4H-imidazolin-4-ones 3. [ABSTRACT FROM AUTHOR]

Abstract: 2,3,4,5-Tetrasubstituted 4,5-dihydro-3H-1,4-benzodiazepines were synthesized in one-pot by a new sequential Ugi 4CC/Staudinger/aza-Wittig reaction, starting from easily accessible o-azidobenzaldehyde, α-amino ketone hydrochloride, isocyanide and carboxylic acid. [Copyright &y& Elsevier]

It is important for the design of radio communication system to understand the plasma distribution in high-temperature flowfield. A numerical method to simulate the complicated plasma flow field around a hypersonic flight vehicle is developed by solving the Navier-Stokes equations with thermo-chemical non-equilibrium source terms. The method is validated by comparison of the distribution of electron number densities with flight experiment. The effects of chemical reaction and thermo-chemical nonequilibrium model the wall temperatures and catalytic activities on the computational results are studied. The distribution of plasma in flow over a lifting body are investigated too. The results show that the electron number densities computed by seven-species and eleven-species chemical model are different obviously when the flowfield temperatures beyond 10000K, and in the case O+ must be taken into account in chemical reaction models besides NO+. The wall conditions, especially the catalytic activities, have a more important effect on the distribution of plasma, the reliable data of the wall catalytic activities, have a more important effect on the distribution of plasma, the reliable data the wall catalytic activities, have a more important effect on the distribution of plasma, the reliable data of the wall catalytic activities, have a more important on the distribution of plasma, the reliable data of the wall catalytic activities and temperatures must be obtained firstly in order to simulate exactly the plasma flow over a lift body. [ABSTRACT FROM AUTHOR]

Abstract: The 6-(4-alkoxycarbonylalkoxy)phenoxy-3-alkylthio-5-(fluoro-substituted)phenyl-1-phenylpyrazolo[3,4-d]pyrimidin-4-ones 6 have been successfully synthesized via a tandem aza-Wittig and annulation reactions of the corresponding iminophosphorances 4, aromatic isocyanate, and substituted phenols 2 in 59–69% isolated yields using actonitrile as solvent. These novel compounds 6 could be oxidized to sulfones 7 by hydrogen peroxide in satisfactory yields (57–93%). Their structures were clearly verified by spectroscopic data (IR, 1H NMR, 13C NMR, MS, Elemental analysis or X-ray diffraction crystallography). The results of preliminary bioassay indicated that these compounds possess herbicidal activity against the root of rape and barnyard grass. [Copyright &y& Elsevier]

The one-pot title reaction starts from aryl substituted Baylis-Hillman phosphonium salts, arylglyoxylates, alkyl cyanides, and primary alkyl amines and does not tolerate aryl amines. [ABSTRACT FROM AUTHOR]

The reactions of phosphonium salts, arylglyoxals, amines, and isocyanides give dihydrobenzazepinones in good yields via a sequential Ugi condensation and intramolecular Wittig reaction. [ABSTRACT FROM AUTHOR]

Title compounds (V) and (VII) are synthesized in a facile one-pot procedure by a new sequential Ugi 4CC/Staudinger/aza-Wittig reaction. [ABSTRACT FROM AUTHOR]

An abstract of the article "One-Pot Synthesis of Isoquinolin-1(2H)-ones by a Sequential Ugi 4CC/Wittig Process" that was published in the previous issue is presented.