Almighty Allah revealed the Holy Qur’an for guidance of the mankind. This guidance cannot be acquired without pondering over the meanings of this book. Different scholars dedicated their lives for understanding and then spreading the message of the Almighty Allah. This book is a study of the work on translations and tafasīr of Holy Qur’an. In Sub-Continent, a large number of religious scholars dedicated themselves for the service of Holy Qur’an. Their vision was broad and they elaborated meanings of the Holy Qur’an according to their own mental approach They were appreciated and criticized by scholars of different sects of the society. There is a dire need to understand and spread the teachings of the Holy book. Hopefully this work will encourage the readers to be aware of the research of theologians. Shāh Walī Allāh is the most important religious figure of Sub-Continent. He and his sons played very important role in spreading the message of Qur’an. Brief services of this family are elaborated in this book. Scholars of Sindh have contributed in writing translations and commentaries of Holy Qur’an. Some of their contributions are highlighted. The reader will also find introduction of well-known translations and tafasīr of the 20th century. But this introduction is restricted to the Sub-continent. Through this book. the writer wants only to motivate people for learning the Holy Book. It is not claimed that services of all the Qur’anic theologians of Sub-continent are highlighted. This is a matter of pride for the author that things are discussed without any prejudice. The readers are the best judges. Suggestions regarding the improvement will be welcomed. I am thankful to Prof. Dr. Shams-ul-Basar and Dr. Zohaib Ahmad for guidance and Co-operation regarding the publication of this work. May Allah Almighty shower blessings on them. If...
Man is always trying to make his life easier and accomplished. He has faced mass destruction in history due to epidemics like small pox, malaria and plague. In order to combat diseases, exploration of man led him to search for causative agents and their control. A time reached when it was found that microbes are themselves a source of potent metabolites which have proved to be effective as drugs and medicines showing great antibiotic activity. It is necessary to find out new sources for potential new antimicrobial compounds. Several hundred important compounds have been isolated which have antibiotic activities and diverse chemical nature. But these compounds should have minimum toxicity to be useful clinically. Because of the increasing resistance of pathogens, there was a never ending desire and need to search for more. Bioactive Compounds have been extracted from microbes which are produced as secondary metabolites. Day by day, new compounds are being discovered giving a hope of golden future of drug industry. The current article emphasizes the importance and need to search for new bioactive compoundsto overcome infections caused by multiple drug resistant (MDR) and biofilm forming pathogens irrespective of the previously present knowledge.
Fossil fuels are a major contributor to the today’s world energy demand as well as greenhouse gases causing global warming. The idea to reduce the dependence on fossil fuels for a green future needs a stepwise transition from fossil fuels to renewable sources. Among the various renewable sources hydrogen is probably the most promising alternative due to its availability, high heating value per unit weight, and zero emissions. The only challenge associated with hydrogen is its safe and feasible storage. The methylcyclohexane-toluene-hydrogen (MTH) system is the one that is considered safe and economical option for hydrogen production, storage and transportation, and utilization. The dehydrogenation reaction of the MTH system is highly endothermic and requires considerable amount of heat energy at a fast rate to have high equilibrium conversions. The successful utilization of hydrogen economy based on the MTH system therefore requires a highly active, selective, and stable dehydrogenation catalyst with its associated reaction kinetics. An intensified dehydrogenation reactor design that supplies high rates of heat transfer to the catalyst bed is also desired. A comprehensive review of the literature regarding kinetics of the methylcyclohexane (MCH) dehydrogenation over Pt containing catalysts has revealed that there is no consensus among the researchers on describing the reaction mechanism, rate-determining step, and inhibition offered by a product. Different researchers have suggested different reaction chemistry and developed different kinetic rate equation. There is hardly a study on the design and simulation of an intensified dehydrogenation reactor that is capable of being used on commercial scale applications. In the present study, an attempt is made to address the discrepancies in the kinetics of the MCH dehydrogenation that exist in the literature. The experimental data of 5 different Pt containing catalysts over a wide range of operating conditions is used to conduct a detailed kinetic study of the dehydrogenation reaction. Various kinetic models are developed based on the power law, Langmuir-Hinshelwood-Hougen-Watson (LHHW), and Horiuti-Polanyi reaction mechanism. The developed kinetic model equations are analyzed both kinetically and statistically and the best fitted kinetic model for each of the catalysts is worked out. The kinetic model based on single-site LHHW kinetics where loss of first hydrogen is the rate limiting step is found appropriate in representing the data of all the catalysts. This leads to report a unified kinetic model for the methylcyclohexane dehydrogenation reaction over any Pt containing catalyst. In addition to that, a new reaction mechanism called associative adsorption of methylcyclohexane is proposed and a kinetic model equation developed based on this mechanism is found successful in representing the relevant experimental data. A 2.0 MW power plant, working on the methylcyclohexane dehydrogenation reaction to yield hydrogen gas as fuel for the power production, is proposed and simulated in Aspen Hysys. The operating conditions such as stream flowrates, temperatures, pressures, and thermal efficiency are worked out. It is found that 17.4148 kmol/h methylcyclohexane are required to produce 2.0 MW net power output. Also, it is found that there is enough energy in the exhaust gases of the turbine that can carry out the dehydrogenation reaction. Using the best-fit kinetic model and the simulation data obtained for 2.0 MW power plant, a novel reactor-heat exchanger design is mathematically modeled and simulated. The proposed reactor configuration is found highly appropriate in carrying out the dehydrogenation reaction.