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Home > Transient Non-Thermal Mobility in Surface Subsurface Hetrogeneous Catalytic Reaction: Computer Simulation

Transient Non-Thermal Mobility in Surface Subsurface Hetrogeneous Catalytic Reaction: Computer Simulation

Thesis Info

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External Link

Author

Qaisrani, Abaid Ullah

Program

PhD

Institute

Gomal University

City

Dera Ismail Khan

Province

KPK

Country

Pakistan

Thesis Completing Year

2007

Thesis Completion Status

Completed

Subject

Physics

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/557

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727629425

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To study the effect of transient non-thermal mobility in surface-subsurface heterogeneous catalytic reaction, simulation work has been done for CO-O 2 and CO- NO catalytic reaction on different surfaces. One class of transient non-thermal mobility of species includes Ely-Rideal (ER) mechanism. The first simple lattice gas model was introduced by Ziff, Gulari and Barshad, as a computer simulation model and is known as the ZGB model, which was used to study CO- O 2 reaction system. It has been found through simulation that ER mechanism generates features in the ZGB model that brings it closer to the real system. The Consideration of ER mechanism annihilates second order phase transition of the ZGB model and the reaction rate begins to increase as soon as feed concentration CO departs from zero, which is consistent with the experimental results. The other class of transient non-thermal mobility is precursor mechanism. This mechanism adds some additional features in the phase diagram of a particular catalytic reaction, which could not be observed by considering the Langmuir-Hinshelwood mechanism. In the precursor mechanism, three different ranges of the surface environment have been investigated. Each environment consists of specific pattern for set of sites around the striking site. It is observed that the reactive window depends on the mobility of the precursors. It is also observed that when the probability of the precursor is increased, the production rates increases. Furthermore, the simulation is also performed to investigate the effect of diffusion of CO on the ZGB model. It has been found that the effect of diffusion of CO on the ZGB model is to increase the mobility of CO on the surface and hence the reaction rate increases with the result that the transition point y 2 shifts towards higher concentration of CO. However, the effect of diffusion of CO has no effect on the second order phase transition point y 1. The effect of diffusion of CO and N (atom) for CO-NO catalytic reaction has also been studied on BCC lattice. The effect of diffusion of CO and N on the production rates is found in the high concentration of CO. This mechanism is found responsible for slight increase in the window width where the concentration of CO is high. Through these models some experimental results have been reproduced of the real system.
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پروفیسر عثمان ادہمی

پروفیسر عثمان ادہمی
یہ خبر بڑے رنج و غم کے ساتھ سنی جائے گی کہ ۱۵؍ مارچ کو دہلی میں پروفیسر عثمان ادہمی کا انتقال ہوگیا ان کا آبائی وطن بستی تھا مگر انہوں نے علی گڑھ میں اپنا مکان تعمیر کرالیا تھا، وہ مسلم یونیورسٹی میں حیاتیات کے پروفیسر تھے۔ ان کی علمی اور تنظیمی صلاحیتوں کا اس وقت زیادہ اندازہ ہوا جب وہ سید حامد صاحب کی وائس چانسلری کے زمانے میں پراکٹر تھے اور غالباً انہی کی تحریک اور جناب حکیم عبدالمجید صاحب کی خواہش پر ادہمی صاحب یونیورسٹی سے سبکدوش ہو کر ہمدرد اسٹڈی سرکل کے ڈائریکڑ ہوئے، ان کی اور سید صاحب کی مشترکہ جدوجہد سے اس کوچنگ سنٹر سے گزشتہ چھ برسوں میں ستر (۷۰) آئی۔اے۔ایس منتخب ہوئے جو ایک بڑا کارنامہ ہے، وہ مولانا آزاد میموریل اکادمی کے صدر بھی تھے جو ایک زمانے میں ان کی جدوجہد سے سرگرم رہی، ادہمی صاحب ایک شریف انسان اور قوم و ملت کے خاموش اور مخلص خادم تھے، وہ نام و نمود اور صلہ و ستائش سے ہمیشہ بے پرواہ رہے۔ ان کی ذاتی زندگی بھی صاف اور پاکیزہ تھی۔ اﷲ تعالیٰ مغفرت فرمائے، متعلقین کو صبر جمیل دے اور ہمدرد اسٹڈی سرکل اور قوم کو ان کا نعم البدل عطا فرمائے۔ آمین! (ضیاء الدین اصلاحی، اپریل ۱۹۹۷ء)

 

ماحولیاتی آلودگی اور تعلیمات نبویﷺ

For the guidance of all human being and for resolving the problems Allah has told in Qur’an.  The environmental pollution is a major issue of our life, Allah has also fully guided for this regard too. There is mentioned in The Holy Quran about that. There are seven types of pollution are: Water pollution, Air pollution, Soil pollution, Thermal pollution, Radioactive pollution, Noise pollution, Light pollution. Environmental pollution has existed for centuries but only started to be significant in dub trial resolution. Pollution occurs when the natural environmental cannot destroy an element without creating harm or damage to itself. The elements involved are not produced by nature and the destroying process can vary from a few days to thousands of years. Though the first we should clean our self then our society will be cleaned and will not remain any kind of pollution. In this regard the Holly Quran is also telling us about the purification. There are two types of purification internal external. Internal purification to purity the soul form the effects of sins and act of disobedience though repenting sincerely form all sins and act of disobedience Purification of the heart from the fifth polytheism. External purification by removing of filth is by using pure water of the water for the removal of the for the worshiper's garment body and from the place of prayer. We must thin for this serious issue and have to reform our society from this important issue. In fort, we get rid from those absolutely in the right direction.

In Vitro Characterization of Hepatitis C Virus Rna Dependent Rna Polymerase

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