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131.
This paper describes a new method for prediction of the Chapman-Jouguet detonation pressures of CHNOFCl explosives using the heat of detonation, Qdet, the number of moles of gaseous products of detonation per gram of explosive, α, and the average molecular weight of gaseous products, M. The equation has the form: PCJ=15.88α(MQdet)1/2ρ02−11.17, where PCJ is the Chapman-Jouguet detonation pressure and ρ0 the loading density. Calculated PCJ by this procedure show good result with respect to measured detonation pressure for any pure or mixture of ideal and some of less ideal CHNOFCl explosives at ρ0>0.8 g/cm3. 相似文献
132.
A mild and efficient method has been reported for preparation of Schiff base ligands through condensation reaction of various aromatic aldehydes and ketones with different aromatic amines in the presence of montmorillonite as a heterogeneous catalyst under solvent free conditions. The advantages of this friendly, economically, environmentally and mild method are such as; simplicity of the reaction procedure, reusability of catalyst, simple work‐up, high product yields and very short reaction times. 相似文献
133.
Hossein Eshghi Zinat Gordi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1553-1557
Abstract A facile and efficient method for the preparation of Z-aldoximes is improved by means of P2O5/SiO2 reagent in solvent-free media. Advantages of this method are the use of inexpensive and selective reagent, with high yields in simple operation, and short reaction time under solvent-free conditions. 相似文献
134.
Majid M. Heravi Neda Zamani Ahari Hossein A. Oskooie Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1701-1712
Abstract Mild and efficient S-methylation of thiols and o-methylation of phenols and naphthols occurs with dimethyl sulfate (DMS) supported on basic alumina under microwave irradiation in solventless system. 相似文献
135.
Saeed Khojaste Effatpanah Mohammad Hossein Ahmadi Seyed Hamid Delbari Giulio Lorenzini 《Entropy (Basel, Switzerland)》2022,24(2)
In recent decades, there has been an increasing trend toward the technical development of efficient energy system assessment tools owing to the growing energy demand and subsequent greenhouse gas emissions. Accordingly, in this paper, a comprehensive emergy-based exergoeconomic (emergoeconomic) method has been developed to study the biomass combustion waste heat recovery organic Rankine cycle (BCWHR-ORC), taking into account thermodynamics, economics, and sustainability aspects. To this end, the system was formulated in Engineering Equation Solver (EES) software, and then the exergy, exergoeconomic, and emergoeconomic analyses were conducted accordingly. The exergy analysis results revealed that the evaporator unit with 55.05 kilowatts and the turbine with 89.57% had the highest exergy destruction rate and exergy efficiency, respectively. Based on the exergoeconomic analysis, the cost per exergy unit , and the cost rate of the output power of the system were calculated to be 24.13 USD/GJ and 14.19 USD/h, respectively. Next, by applying the emergoeconomic approach, the monetary emergy content of the system components and the flows were calculated to evaluate the system’s sustainability. Accordingly, the turbine was found to have the highest monetary emergy rate of capital investment, equal to , and an output power monetary emergy of . Finally, a sensitivity analysis was performed to investigate the system’s overall performance characteristics from an exergoeconomic perspective, regarding the changes in the transformation coefficients (specific monetary emergy). 相似文献
136.
Hossein Vahabi Laurent Ferry Claire Longuet Rodolphe Sonnier Claire Negrell-Guirao Ghislain David José-Marie Lopez-Cuesta 《European Polymer Journal》2012,48(3):604-612
The influence of phosphonated groups on thermal degradation and flammability has been investigated in the case of two chemically modified PMMA. Thermogravimetric analysis as well as pyrolysis combustion flow calorimetry have been used to define the efficiency of phosphorus in both condensed and vapor phases. A theoretical study was also performed to determine the contribution of phosphonated groups to the effective heat of combustion, residue content and heat release capacity. Empirical and theoretical approaches agreed to highlight that PMMA modified with monophosphonated comonomer is more efficient in both condensed and vapor phases in terms of flammability and char formation. These results were attributed to the ability of phosphonate groups to interact with ester groups and also to the weakness of the P–C–N bonds. Moreover, this study proposes a method for designing the chemical environment of phosphonate group in polymers to achieve better flame retardancy. 相似文献
137.
Hossein Anaraki-Ardakani Shirin Sadeghian Foroghossadat Rastegari Alireza Hassanabadi 《合成通讯》2013,43(12):1990-1999
The three-component reaction between dialkyl acetylenedicarboxylates and triphenylphosphine in the presence of arylsulfonyl hydrazides or aryl hydrazines produces highly functionalized, salt-free phosphorus ylides in excellent yields. 相似文献
138.
139.
Mehrnoosh Farahmand Hosein Mohammadzadeh Hossein Mehri-Dehnavi Robabeh Rahimi 《International Journal of Theoretical Physics》2017,56(3):706-719
We study superdense coding with uniformly accelerated particle in single mode approximation and beyond single mode approximation. We use four different functions, the capacity of superdense coding, negativity, discord and the probability of success for evaluating the final results. In single mode approximation, all the four functions behave as expected, however in beyond single mode approximation, except the probability of success, the other three functions represent peculiar behaviors at least for special ranges where the beyond single mode approximation is strong. 相似文献
140.
Mohammad Hossein Tavakoli Hossein KarbaschiFeridoun Samavat Ebrahim Mohammadi-Manesh 《Journal of Crystal Growth》2010,312(21):3198-3203
A set of 2D finite element numerical simulation of induction heating process for an oxide Czochralski crystal growth system has been made for a range of f=1–100 kHz applied frequency of driving current. It was shown that the frequency selection has a marked effect in all basic induction phenomena, including electromagnetic field distribution, skin depth, coil efficiency, and intensity and structure of heating in the growth setup. 相似文献