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131.
Mukhtar Amir Nasir Habib Rashid Badar Waheed Hizba 《Journal of Thermal Analysis and Calorimetry》2019,138(6):3939-3947
Journal of Thermal Analysis and Calorimetry - For effective and reliable ignition of ammonium perchlorate and hydroxyl-terminated polybutadiene (AP/HTPB) solid composite propellant base bleed (BB)... 相似文献
132.
Hashem Sharghi Omid Asemani Seyed Mohammad Hossein Tabaei 《Journal of heterocyclic chemistry》2008,45(5):1293-1298
TsOH/graphite and N,N‐dimethylaniline/graphite were found to be catalyst systems for condensation reaction of o‐phenylendiamine with different aldehydes to form benzimidazole derivatives under mild and simple conditions. The graphite was easily recovered by a simple extraction and could be reused without decrease of activity in the presence of fresh TsOH and N,N‐dimethylaniline. 相似文献
133.
Kohzadian Alireza Filian Hossein Kordrostami Zahra Zare Abdolkarim Ghorbani-Choghamarani Arash 《Research on Chemical Intermediates》2020,46(3):1941-1953
Research on Chemical Intermediates - In this paper, a rapid, easy and very efficient method for the synthesis of bis(pyrazolyl)methanes has been reported in the presence of nickel–guanidine... 相似文献
134.
Amirhossein Saali Mohammad Shokouhi Hossein Sakhaeinia Nima Kazemi 《Journal of solution chemistry》2020,49(3):383-404
The thermodynamic consistency test of solubility P–T–x data for binary mixtures including carbon dioxide (CO2) + a room temperature ionic liquid has been investigated. Experimental solubility data taken from the open literature for 32 binary mixtures of CO2/RTILs contains 80 isotherms. The applied consistency test is based on the fundamental Gibbs–Duhem equation with use of the generic Redlich–Kwong (GRK) equation of state (EoS) coupled with the van der Waals–Berthelot (GRK/vdWB) mixing rule. The optimum parameters were obtained by minimizing the summation of per cent relative deviations between modeled and experimental data, based on the bubble pressure algorithm. Modeling was found acceptable for all isotherms, which demonstrated the usability of the GRK equation of state. Results of the thermodynamic consistency test showed that 36 of the isothermal data sets were thermodynamically consistent, 37 were not fully consistent, 6 were thermodynamically inconsistent and only one data set was found to need another model. 相似文献
135.
136.
137.
A quantum chemical study has been carried out to investigate the effects of the size of H2O cluster and substituents (X = H, Me, OMe, CHO, NO, and NO2) in the para position of the anilide ion on the two-bond spin–spin coupling constants (SSCCs) 2h
J
N···O across in the N–H–O switching at B3LYP/6-311 ++G(2d,2p) level of theory. The changes in 2h
J
N···O SSCCs due to variation of substituent and H2O cluster size were well monitored by changes in binding energy, structural parameter, electron density topography, natural
charge, charge transfer, and percentage of p-character of N atom in the C–N bond. Linear correlations were found between 2h
J
N···O and above-mentioned properties. 相似文献
138.
Chambreau SD Boatz JA Vaghjiani GL Koh C Kostko O Golan A Leone SR 《The journal of physical chemistry. A》2012,116(24):5867-5876
In order to better understand the volatilization process for ionic liquids, the vapor evolved from heating the ionic liquid 1-ethyl-3-methylimidazolium bromide (EMIM(+)Br(-)) was analyzed via tunable vacuum ultraviolet photoionization time-of-flight mass spectrometry (VUV-PI-TOFMS) and thermogravimetric analysis mass spectrometry (TGA-MS). For this ionic liquid, the experimental results indicate that vaporization takes place via the evolution of alkyl bromides and alkylimidazoles, presumably through alkyl abstraction via an S(N)2 type mechanism, and that vaporization of intact ion pairs or the formation of carbenes is negligible. Activation enthalpies for the formation of the methyl and ethyl bromides were evaluated experimentally, ΔH(?)(CH(3)Br) = 116.1 ± 6.6 kJ/mol and ΔH(?)(CH(3)CH(2)Br) = 122.9 ± 7.2 kJ/mol, and the results are found to be in agreement with calculated values for the S(N)2 reactions. Comparisons of product photoionization efficiency (PIE) curves with literature data are in good agreement, and ab initio thermodynamics calculations are presented as further evidence for the proposed thermal decomposition mechanism. Estimates for the enthalpy of vaporization of EMIM(+)Br(-) and, by comparison, 1-butyl-3-methylimidazolium bromide (BMIM(+)Br(-)) from molecular dynamics calculations and their gas phase enthalpies of formation obtained by G4 calculations yield estimates for the ionic liquids' enthalpies of formation in the liquid phase: ΔH(vap)(298 K) (EMIM(+)Br(-)) = 168 ± 20 kJ/mol, ΔH(f,?gas)(298 K) (EMIM(+)Br(-)) = 38.4 ± 10 kJ/mol, ΔH(f,?liq)(298 K) (EMIM(+)Br(-)) = -130 ± 22 kJ/mol, ΔH(f,?gas)(298 K) (BMIM(+)Br(-)) = -5.6 ± 10 kJ/mol, and ΔH(f,?liq)(298 K) (BMIM(+)Br(-)) = -180 ± 20 kJ/mol. 相似文献
139.
The electrooxidation of Gabapentin was studied on nanotubes of nickel oxide-modified carbon paste electrode for the first time. Cyclic voltammetry was employed to investigate the electrooxidation process. A simple, sensitive, and efficient amperometric method was developed for the analysis of the drug, and the corresponding analytical parameters were reported. For Gabapentin, a detection limit of 0.3 μM was obtained in a linear range of 2.4–50 μM. The proposed amperometric method was also applied to the analysis of commercial capsules, and the results were in good agreement with the declared values. Also, the applicability of the method to the direct assay of the drug in human serum and urine was described. 相似文献
140.