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1.
Komeili Samane Takht Ravanchi Maryam Taeb Abbas 《Research on Chemical Intermediates》2018,44(2):1335-1349
Research on Chemical Intermediates - 0.03 wt% Pd catalysts on nickel and zinc aluminate supports were prepared by impregnation. The samples were characterized by XRD, BET, ICP, SEM, EDS,... 相似文献
2.
Mitra Ghassemzadeh Forough Adhami Abas Taeb Majid M. Heravi Bernhard Neumüller 《无机化学与普通化学杂志》2005,631(9):1568-1570
The reaction of 4‐amino‐6‐methyl‐1,2,4‐triazine‐3‐thione‐5‐one, HAMTTO, with silver (I) nitrate in methanol led under deprotonation to the polymeric compound [(AMTTO)Ag]n. The coordination polymer {[Ag(HAMTTO)]ClO4}n ( 1 ) is synthesized from the reaction of the latter polymeric compound with perchloric acid. Both compounds were characterized by elemental analysis and IR spectroscopy. Single‐crystal X‐ray diffraction studies on compound 1 showed that HAMTTO acts as a bidentate ligand and chelates the silver atom via its hydrazine nitrogen atom and its sulfur atom. Crystal data for 1 at ?90 °C: space group P21, Z = 2, a = 629.3(1), b = 748.7(1), c = 1071.7(1) pm, β = 98.28(1)°, R1 = 0.0533. 相似文献
3.
The kinetics of propane dehydrogenation and catalyst deactivation over Pt-Sn/Al2O3 catalyst were studied.Performance test runs were carried out in a fixed-bed integral reactor.Using a power-law rate expression for the surface reaction kinetics and independent law for deactivation kinetics,the experimental data were analyzed both by integral and a novel differential method of analysis and the results were compared.To avoid fluctuation of time-derivatives of conversion required for differential analysis,the conversion-time data were first fitted with appropriate functions.While the time-zero and rate constant of reaction were largely insensitive to the function employed,the rate constant of deactivation was much more sensitive to the function form.The advantage of the proposed differential method,however,is that the integration of the rate expression is not necessary which otherwise could be complicated or impossible.It was also found that the reaction is not limited by external and internal mass transfer limitations,implying that the employed kinetics could be considered as intrinsic ones. 相似文献
4.
Mitra Ghassemzadeh Forough Adhami Majid M. Heravi Abas Taeb Soheila Chitsaz Bernhard Neumüller 《无机化学与普通化学杂志》2001,627(5):815-819
The reaction of [(Ph3P)2CuCl]2 with 4‐amino‐6‐methyl‐1,2,4‐triazine‐thione‐5‐one (AMTTO, 1 ) in methanol and further recrystallization from methanol/acetone solution gives [(C4H4N3SON(=CMe2)Cu(PPh3)2Cl] ( 2 ) as a neutral complex. [(C4H4N3SON(=CMe2)Ag(PPh3)2]NO3 ( 4 ) can be obtained in excellent yield by the reaction of [(AMTTO)2Ag]NO3 ( 3 ) with triphenylphosphane in methanol/acetone. Both complexes were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for 2 at –80 °C: space group P1 with a = 1233.8(1), b = 1389.7(1), c = 1417.1(1) pm, α = 89.36(1)°; β = 65.10(1)°, γ = 65.95(1)°, Z = 2, R1 = 0.0582 and for 4 at –80 °C: space group P1, with a = 1193.3(1), b = 1308.5(1), c = 1385.3(1) pm, α = 94.69(1)°, β = 109.14(1)°, γ = 93.42(1)°, Z = 2, R1 = 0.0716. 相似文献
5.
The solubility data of acetaminophen in binary mixtures of 1-hexyl-4-methylpyridinium bromide and water were obtained over the temperature range from 293.15 to 313.15 K by using the gravimetric method under atmospheric pressure. Using the experimentally measured solubility values, the thermodynamic properties of dissolution, mixing and transfer processes were evaluated. The measured solubilities were correlated by the modified Wilson and the electrolyte non-random two liquid (E-NRTL) models. 相似文献
6.
Latent or unobserved phenomena pose a significant difficulty in data analysis as they induce complicated and confounding dependencies among a collection of observed variables. Factor analysis is a prominent multivariate statistical modeling approach that addresses this challenge by identifying the effects of (a small number of) latent variables on a set of observed variables. However, the latent variables in a factor model are purely mathematical objects that are derived from the observed phenomena, and they do not have any interpretation associated to them. A natural approach for attributing semantic information to the latent variables in a factor model is to obtain measurements of some additional plausibly useful covariates that may be related to the original set of observed variables, and to associate these auxiliary covariates to the latent variables. In this paper, we describe a systematic approach for identifying such associations. Our method is based on solving computationally tractable convex optimization problems, and it can be viewed as a generalization of the minimum-trace factor analysis procedure for fitting factor models via convex optimization. We analyze the theoretical consistency of our approach in a high-dimensional setting as well as its utility in practice via experimental demonstrations with real data. 相似文献
7.
Mitra Ghassemzadeh Forough Adhami Majid M. Heravi Abas Taeb Soheila Chitsaz Bernhard Neumüller 《无机化学与普通化学杂志》2002,628(13):2887-2893
The complexes [Cu(AMTTO)Cl2] ( 2 ), [Cu(AMTTO)2]Cl ( 3 ), and [Cu(AMTTO)(PPh3)2Cl] ( 4 ) have been prepared and characterized by IR spectroscopy and elemental analyses. Also single‐crystal X‐ray diffraction studies on compound 2 , 3 and 4 revealed that AMTTO acts in 2 as a bidentate ligand via nitrogen and sulfur atoms, in 3 and 4 as a monodentate via sulfur atoms. Complex 3 was already mentioned in literature, but the structure was not described in detail. The molecules in 2 form infinite chains through additional weak Cu—S interactions along [010] indicating the Jahn‐Teller distortion of the d9 ion Cu2+. The infinite chains are connected by hydrogen bonding along [100]. Crystal data for 2 at —80°C: monoclinic, space group P21/m, a = 666.7(1), b = 609.4(1), c = 1132.6(2) pm, b = 95.46(2)°, Z = 2, R1 = 0.0365; for 3 at —80°C: orthorhombic, space group Pbcn, a = 1291.2(2), b = 1146.5(1), c = 1000.5(1) pm, Z = 4, R1 = 0.0315; for 4 at —80°C: monoclinic, space group, P21/n, a = 879.4(1), b = 1849.3(2), c = 2293.8(3) pm, β = 92.38(1)°, Z = 4, R1 = 0.0688. 相似文献
8.
Forough Adhami Mitra Ghassemzadeh Majid M. Heravi Abas Taeb Bernhard Neumüller 《无机化学与普通化学杂志》1999,625(9):1411-1412
The reaction of 4-amino-6-methyl-1,2,4-triazine-3(2 H)-thione-5-one (AMTTO) with silver(I) nitrate in methanol gives the complex [Ag(AMTTO)2]NO3 ( 1 ). 1 was characterized by IR and 13C NMR spectroscopy and by an X-ray structure analysis [space group C2/c, Z = 4, lattice dimensions at –80 °C: a = 1306.7(2), b = 1139.0(2), c = 1089.2(1) pm, β = 94.54(1)°, R1 = 0.0294]. The cation possesses a highly distorted linear coordination sphere in the solid state. 相似文献
9.
Farnaz Tahriri Zangeneh Abbas Taeb Khodayar Gholivand Saeed Sahebdelfar 《Journal of Energy Chemistry》2013,22(5):726-732
The kinetics of propane dehydrogenation and catalyst deactivation over Pt-Sn/Al2O3 catalyst were studied. Performance test runs were carried out in a fixed-bed integral reactor. Using a power-law rate expression for the surface reaction kinetics and independent law for deactivation kinetics, the experimental data were analyzed both by integral and a novel differential method of analysis and the results were compared. To avoid fluctuation of time-derivatives of conversion required for differential analysis, the conversion-time data were first fitted with appropriate functions. While the time-zero and rate constant of reaction were largely insensitive to the function employed, the rate constant of deactivation was much more sensitive to the function form. The advantage of the proposed differential method, however, is that the integration of the rate expression is not necessary which otherwise could be complicated or impossible. It was also found that the reaction is not limited by external and internal mass transfer limitations, implying that the employed kinetics could be considered as intrinsic ones. 相似文献
10.
Samane?KomeiliEmail author Abbas?Taeb Maryam?Takht Ravanchi Maryam?Rahimi Fard 《Research on Chemical Intermediates》2016,42(12):7909-7921
Nickel aluminates were prepared by sol–gel and impregnation methods and calcined at 1100 °C. The sol–gel made samples were prepared with different amounts of nickel (Ni/Al molar ratio equal to 0, 0.25, 0.5, and 0.75) and aging times (24 and 48 h). The samples were characterized by X-ray diffraction, induced couple plasma, nitrogen physisorption, transmission and scanning electron microscopy, and ammonia temperature programmed desorption (NH3-TPD). In the sol–gel made samples, only the NiAl2O4 structure of nickel aluminate was defined, while for impregnation, NiAl10O16 was formed as well. The sol–gel made samples had low specific surface areas (7.7–12.4 m2/g), but a sample prepared by impregnation method had higher specific surface area (67.2 m2/g). The surface acidity density decreased by increasing the amount of nickel and was the lowest for impregnation method. 相似文献