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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

Access Option

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

Similar


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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باب نہم: قدرتی وسائل کےآداب واخلاق

طہارت و نظافت کا اصول

اسلام زندگی بسرکرنے کے ہر پہلو کے متعلق ہدایات و احکام کا جامع تصور دیتا ہے۔ اسلام میں پاک و صاف وسائل ِ حیات کے استعمال کی ترغیب دی گئی ہے۔ اسلام میں طہارت و نظافت کے معاملے میں انتہائی مثالی تعلیمات و ہدایات بیان کی گئی ہیں۔ اسلام آلودگی و گندگی سے نفرت اور صفائی و پاکیزگی سے محبت کا جذبہ پیدا کرتا ہے۔ اصول ِ طہارت پر عمل کرنا حکم الہی ہے۔ طہارت کے اصول کی پیروی سے انسان فکری پاکیزگی حاصل کرتا ہے۔ اگر کوئی انسان اپنے نفس کو پاکیزہ رکھنا چاہتا ہے تو اسے لا محالہ طہارت کے اصول پر عمل کو اپنی اولین خصلت بنا نا ہوگا۔ طہارت کے اہتمام سے انسانی قلب و رووح میں نورانیت پیدا ہو جاتی ہے۔ فقہ اسلامی کی ہر کتاب کا آغاز کتاب "کتاب الطھارۃ "کیا جاتا ہے۔ شاہ ولی اللہ ؒ نے حجتہ اللہ البالغہ میں طہارت و نظافت کے اصول پر تفصیلی اور فکر انگیز روشنی ڈالی ہے اور اصول ِ طہارت کو اساسیاتِ اخلاق کے اولین درجے پر فائز کیا ہے۔ اصول طہارت کی پیروی انسانی فطرت کا خاصہ ہے۔

علامہ راغب اصفہانی کے مطابق طہارت کی دواقسام ہیں:

" والطَّهَارَةُ ضربان: طَهَارَةُ جسمٍ، وطَهَارَةُ نفسٍ، وحمل عليهما عامّة الآيات"[1]

طہارت کی دو قسمیں ہیں: 1۔ جسمانی و ظاہری طہارت 2۔ قلبی و باطنی طہارت قرآنی آیات میں جہاں بھی طہارت کا ذکر کیا گیا ہے، وہاں یہ دونوں قسم کی طہارت و نظافت پر عمل کرنا مراد ہوتاہے۔ امام بخاری ؒ نے صیح بخاری کا آغاز نیت کے اخلاص یعنی قلبی پاکیزگی سے کیا ہے۔ یعنی دل کی صفائی کو جسم کی صفائی پر فوقیت و برتری حاصل ہے۔

قرآن...

The Quranic Statements on Blood and Flesh and Medical Science

The Qur’an has mentioned, among so many things, animal blood and flesh. It so appears that all of its statements on these two matters are invariably in agreement with the modern medical science. The Qur’an declares the dead-animal as forbidden for consumption. There are reasons for that. Medical science provides justification for non-consumption of dead animals’ flesh and blood. This article discusses how medical science supports the Qur’anic injunction on animals’ flesh and blood.

Impact of Theileriosis in Naturally Infected Cattle and Buffaloes

Tick born infections are most common problem in dairy animals of tropical region. This infection causes heavy economical losses in terms reduced milk yield and meet production. Keeping in view the economic importance of tick born infection i.e Theileriosis, present study was organized to resolve the consequences of Theileriosis on naturally infected cattle and buffaloes. The objective of the study was occurrence of disease and correlate exposure of ticks and tick-borne Theileriosis at the peri-urban and urban areas of Hyderabad, Sindh, Pakistan. Data was collected from the selected farmers in study areas through survey questionnaire. Ticks and blood samples of 2400 buffaloes and 300 cows were collected from 20 dairy farms of urban and Peri-urban areas of Hyderabad, during November 2013 to October 2014. Ticks were identified on the basis of their physical characteristics. Thin blood smears were prepared and stained for identification of Theileria spp. DNA was extracted from blood samples of non infected (control) and infected cows and buffaloes. Extracted DNA was amplified by specific genes of Theileria spp. through Polymerase Chain Reaction (PCR) to detect the Theilerial infection in both animal species. Microscopic examination of blood from suspected cows revealed 73 % and 76% prevalance of thielarial infection in urban and peri-urban areas respectively. Buffaloes showed 65% and 75% prevalnce in urban and peri-urban areas respectively. Overall prevlance of thielariosis in cows was higher i.e 75% than buffaloes which is 70%. Cows and bufflaoes in urabn areas showed less prevalance of Theilariosis than peri-urban areas. PCR results given overall infection rate in cows was calculated as 79% that is higher than that in buffaloes which is 76%. Comparative results indicated higher infection rate on PCR than by staining method. Analytical investigations of data revealed significant difference (P<0.05) between prevalance percentage between both species as well as between urban and perii-urban areas of Hyderabad. Identification of ticks indicated that Hyalomma antolicum anatolicum was the highly prevalent tick in both peri-urban and urban areas i.e. 44.32 %, and 44.57% respectively. High tick infestation in cows were in external genitalia, udder and perineum (45%) followed by dewlap (20%), inner thighs (15%).Where as in buffaloes external genitalia, udder and perineum (55%) followed by dewlap (23%). Clinical examination of infected cows indicted anorexia (88%), fever (87%), pale mucus membrane (75%) and enlargement of lymph nodes (47%). Whereas, infected buffaloes had anorexia 95%, fever (91%), pale mucous membrane (80%) and enlarged lymph nodes (49%). Nasal discharge, skin lesions and diarrhea were the minor signs in both species. Analysis of associated risk factors affecting prevalence of tick infestation and Theilerial infection in cows and buffaloes determined the type of house and housing, environmental conditions, gender and age of significantly affects on prevalence of theileriosis. Prevalence was high in semi-intensive house with kacha floor, during months of July to October in adult females. Complete Blood count investigations showed statistically a significant decrease in mean Hgb, PCV, MCH, RBCs, WBCs (P<0.001),whereas significant increase was noted LY count corpuscular volume (P<0.001). It was concluded from the current study that Haylomma anatolicum anatolicum is a vector of Theileria annulata. Load of vector tick and risk of infection is greatly influenced by housing system, climatic conditions. Sensitivity to infection also varies in male, female and also different age groups; adult females are more sensitive to tick infestation as compare to male and young animals. Molecular detection is more sensitive and specific method for detection of Theileria. Theilerial infection influences the blood, causing blood loss anemia resulting in ill health of cows and buffaloes. Chemical analysis of milk of infected cows and buffaloes revealed that protein, ash and lactose were significantly declined (P<0.05) whereas, fat and total solids were significantly increased (P<0.05) in Theileria infected cows and buffaloes, but pH and acidity was unaffected. Financial losses occur in terms of reduced quality and quantity of milk and meat. The total financial fall of RS- 0.17 million / animal was recorded in current study. Theileriosis is one of main causes of financial fall for livestock holders.