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Study of Physical Mechanisms of Regenerative Sooting Discharges

Thesis Info

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Author

Janjua, Sohail Ahmad

Program

PhD

Institute

Pakistan Institute of Engineering and Applied Sciences

City

Islamabad

Province

Islamabad

Country

Pakistan

Thesis Completing Year

2007

Thesis Completion Status

Completed

Subject

Physics

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/472

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727385312

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This thesis describes the experimental study of the sooting discharges in which a variety of carbon clusters is produced. The regenerative sooting discharges have been studied and their carbon cluster forming characteristics are compared with the non-regenerative sooting discharges. A large number of experimental arrangements have been used in which sublimation and sputtering processes were investigated in detail to understand the basic mechanisms for the formation of carbon clusters. The effects of experimental parameters on the clusters formed in the two types of carbonaceous discharges i.e. the non-regenerative and the regenerative sooting discharges are reported. Continuous as well as pulsed operations of the discharges have been studied. The carbon clusters are produced in carbonaceous environments where either the high temperature arc discharges sublime the graphite electrodes or the glow/arc discharges in the graphite hollow cathodes take place with sputtering being the dominant mechanism. Regenerative soot is shown to have different characteristics and constituents compared with those in the non-regenerative soot. We have shown that small clusters dominate in the regenerative sooting discharges. The basic constituents of the two types of soot are also different; in the case of the regenerative soot C 3 is the basic constituents while for the non- regenerative soot C 2 seems to be an essential basic unit. Emission spectroscopy of the non- regenerative discharges indicates the predominance of diatomic carbon C 2 in the continuous as well as the pulsed modes. C 2 is the main sublimed species. Under these conditions cage closure leading to fullerenes and nanotubes is more likely. Mass spectrometry with an ExB Wien velocity filter has been used to complement the results of emission spectroscopy in the case of the regenerative soot. The mass spectra from graphite hollow cathode duoplasmatron ion source clearly show that C 3 is the major surviving specie along with other clusters C 4 & C 5 with lesser yields. The environment of the twin plasmas in the duoplasmatron ion source is such that higher clusters cannot survive and are fragmented into smaller clusters with C 3 as the dominant end product.
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مولانا سید فخرالدین احمد

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اس حادثہ کے چند روز بعدہی مولانا سید فخرالدین احمدصاحب کاحادثہ وفات پیش آیا۔ حضرت شیخ الہند ؒ کافیضِ درس وتربیت ایک ابرکرم تھا جوعرب و عجم کے ہر خطے بربرسا اور ہرشخص نے بقدر حوصلہ واستعداد اس سے استفادہ کیا لیکن مولانا حضرت شیخ کے ان چند تلامذہ وتربیت یافتہ حضرات میں سے تھے جو علم وعمل، ورع وتقوی اور فکرونظر کے اعتبارسے اپنے استاد وشیخ کے قالب میں ڈھل گئے تھے۔ چنانچہ ایک طرف ان کی حسین شخصیت درس حدیث کے مسند کی زینت تھی تو دوسری جانب زہد وورع اورعبادت و ریاضت کے سجادہ کی رونق۔ وہ ایک طرف بلند پایہ اوروسیع النظر عالم محدث وفقیہ تھے تواس کے ساتھ ہی جنگ آزادی اور میدان استخلاص وطن کے بہادر سپاہی اورمجاہد بھی تھے۔ یہی وجہ ہے کہ مشغلہ درس وتدریس کے باوجود جمعیۃ العلماء سے اس کے ایک فعال ممبر کی حیثیت سے ہمیشہ وابستہ رہے۔ عمرکااکثروبیشتر حصہ مدرسہ شاہی مراد آباد کی خدمت میں صرف ہوا۔شیخ الاسلام مولانا حسین احمدمدنی کی وفات حسرت آیات کے بعد دارالعلوم دیوبند کے شیخ الحدیث بھی مقرر ہوئے اورجمعیت علمائے ہند کے صدر بھی اور آخراسی پردنیا سے رخصت ہوگئے۔ عمرکم وبیش پچاسی برس کی پائی۔ادھر چندسال سے چند در چند عوارض واسقام کے باعث بہت کمزور اورچلنے پھرنے سے معذور سے ہوگئے تھے۔ لیکن اس کے باوجود، اس کوان کی روحانی طاقت یاقوت ارادی کے علاوہ اورکیا کہیے کہ جب وہ درس بخاری کے لیے بیٹھتے تھے توگھنٹوں ایک ہی نشست سے بیٹھے رہتے تھے ۔ درس اور اسی سلسلہ میں طلباکے سوالات کے جوابات پوری حاضر حواسی سے دیتے تھے اور تقریر کے وقت آواز میں بھی ضعیفی وپیری کاکوئی اثرمحسوس نہیں ہوتا تھا۔طبعاً کم گو تھے، مگر جب ضرورت ہوتی تھی تو تقریر بہت واضح اورمدلل کرتے تھے۔خود بزرگ اور...

Pengaruh Kinerja Kepegawaian Dalam Administrasi Perkantoran

Penelitian ini bertujuan untuk mengetahui dan menganalisis hubungan pengaruh kinerja kepegewaian dalam administrasi perkantoran di kantor camat kecamatann Tuhemberua kabupaten Nias Utara. Populasi dalam penelitian ini adalah pegawai Kantor Camat Kecamatan Tuhemberua yang berjumlah 12 orang. Jenis data yang digunakan dalam penelitian ini adalah data primer. Teknik pengumpulan data dengan angket, wawancara, observasi, ujian (test) dokumentasi. Teknik analisis data dengan melakukan verifikasi data, pengelolaan angket, dan pengolahan data: (a). Uji validitas data, (b). Uji reliabilitas data, dan (c). Pengujian hipotesis. Dari hasil perhitungan koefisien korelasi diperoleh rhitung (rxy) = 0,834 jika dikonsultasikan pada tabel harga kritik r produk moment untuk interval kepercayaan 5% setelah di hitung rhitung = 0,834 > rtabel = 0,576. Berdasarkan regresi linear sederhana maka sumbangan kinerja kepegawaian terhadap administrasi perkantoran di Kantor Camat Gunungsitoli Tuhemberua 2,668. Dari perhitungan koefisien determinasi besarnya pengaruh variabel x terhadap variabel y di Kantor Camat Gunungsitoli Tuhemberua 69, 48%. Berdasarkan kriteria pengujian hipotesis ternyata Ha adanya pengaruh dan H0 tidak adanya pengaruh, sebab thitung = 7, 20 > rtabel = 2,160 sehingga dapat dinyatakan adanya pengaruh kinerja kepegawaian terhadap administrasi perkantoran pada kantor camat Tuhemberuaa kabupaten Nias Utara.

Socio-Economic Determinants of Crimes: An Empirical Analysis of Prisoners in Punjab

Becker’s (1968) contribution to economics of crime has led the economists to dig out the causes and consequence of crimes. However, the menace of crimes adversely affects the overall social, economic and political health of a country. It is, therefore, imperative to identify the socio-economic determinants of crimes. The present work is an attempt to explore the socio-economic factors of crimes through conducting survey of the prisoners arrested against the charges of theft, robbery, dacoity and financial fraud in different prisons in Punjab. Other objectives include the elucidation of socio-economic and demographic characteristics of prisoners. The study was carried out in the Punjab because it has 53 percent of the country’s population, 60 percent of the total reported crimes and 67 percent of the prison population of Pakistan. A well-structured questionnaire was designed to interview prisoners and cluster sampling technique was used to draw the representative sample. A survey of 967 prisoners, regardless of their legal status, was conducted in 30 prisons in Punjab. The survey revealed that 50 percent prisoners were arrested for the indictment of theft, 21 percent were kept in the prisons due to robbery, 17 percent were arrested for dacoity, 11 percent were financial fraud offenders and only 1 percent was of the prisoners were arrested due to other crimes. Among prisoners arrested for theft, 10 percent held unemployment responsible for their involvement and 41 percent told that due to poverty they had committed theft. However, 6 percent claimed that due to family issues they had committed theft and 41 percent told different reasons of their participation in theft. Similarly, among prisoners arrested against the charges of robbery, 31 percent held poverty, 16 percent blamed unemployment, 7 percent told family background and 46 percent stated different reasons of their involvement in robbery. Prisoners of dacoity alleged poverty (26 percent), unemployment (8 percent), family background (10 percent) and different reasons (56 percent) of their detention. Only 8 percent of the financial fraud prisoners held unemployment, poverty, family background and keeping up with the joneses responsible of their involvement in financial fraud; however, the remaining 92 percent explained several reasons of their participation in financial fraud. Depending upon the nature of data, binary logistic regression technique was used to find out the relationship between socio- economic determinants and crimes. The results of binary logistic regression of the relationship between theft and socioeconomic determinants without including prison population background characteristics revealed that unemployment and family background had insignificant relationship with theft whereas poverty and other reasons had significant relationship with theft. Similar results were found when prison population background characteristics were included in the model. The relationship between robbery and socioeconomic determinants without prisoner background characteristics explained that unemployment and other reasons had significant relationship with robbery while poverty and family issues had insignificant relationship with robbery. On the other hand, by incorporating the prisoner background characteristics, only unemployment had significant relationship with robbery. The relationship between dacoity and socioeconomic determinants without prisoner background characteristics showed that only family issues had significant relationship with dacoity. The inclusion of prisoner background characteristics in the model resulted in insignificant relationship with unemployment, poverty, family background and other reasons. However, financial fraud had significant relationship with unemployment, poverty and other reasons while family background had insignificant relationship. Similar estimates were obtained when prisoner background characteristics were included in the model. The findings revealed that socio-economic and demographic characteristics provoke individuals to get involved in theft, robbery, dacoity and financial fraud in Punjab.