In modern science and technology the glow discharges have a wide varity of applications. In microelectronics industry the glow discharges are used for etching of surfaces to from topographical surface features, as well as for deposition of thin films. In material processing industry the glow discharges are used extensively for deposition of various thin films, coatings and surface layers. In the present work the diagnostics of pulsed DC generated nitrogen-hydrogen mixture plasma, using an Active Screen Cage is performed so that the optimum working conditions for the purpose of material processing are obtained. Trace rare gas optical emission spectroscopy is used to investigate the effect of current density, filling pressure and hydrogen concentration for the measurement of excitation temperature, vibrational temperature, dissociation fraction and nitrogen atom density. The nitrogen plasma is generated by using 50 Hz pulsed-DC power source. The excitation temperature is determined from Ar-I line intensities, using Boltzmann’s plot method. It has been observed that the excitation temperature increases with both current density and hydrogen concentration, where as it decreases with filling pressure. In order to find out the vibrational temperature of the second positive ?ʋ(?3??,?́→?3??,?̋) system, the Δ? = -2 sequence is used due to comparatively longer lifetime (τ ~ 36 ns) using Boltzmann’s plot method. The behavior of the vibrational temperature remains similar like in the case of excitation temperature. The nitrogen dissociation fraction is calculated using actinometery and line ratio methods. It is observed that the dissociation fraction increases by adding 40% of hydrogen in the nitrogen plasma and then upon further increase of hydrogen concentration it decreases sharply. The atomic density of nitrogen is also calculated using actinometery method, which also increase with hydrogen concentration up to 40% hydrogen in the mixture. Using the optimum condition of current density, filling pressure and hydrogen concentration, different types of steels including AISI 316, AISI 304, mild steel and high xviii carbon steel are nitrided in the presence of the active screen cage. The treated samples are analysed by X-ray diffractrometery (XRD) to investigate the changes in the crystallographic structure. Scanning electron microscope (SEM) is used to investigate the surface morphology of the plasma irradiated samples, where the changes in the surface hardness are measured by Vickers microhardness tester. The XRD pattern of all the samples confirms the presence of nitrides with iron, carbon and chorimum. Microhardness results reveal a 3-7 times harder surface for different samples. The nitrogen mass transfer mechanism in active screen cage plasma nitriding process is also investigated using optical emission spectroscopy. The dominant species including NH, Fe-I, ?2+, N-I and N2 along with ??and ?? lines are observed using optical emission spectroscopy (OES). The factor of sample treatment time for both of Active screen cage and DC plasma nitriding of AISI 316 stainless steel are investigated. Increasing trend in microhardness is observed in both cases but three-fold more hardness is achieved using Active Screen Cage in comparision to direct current plasma nitriding. On the basis of metallurgical and OES observations a new phenomelogical scheme for a nitrogen mass transfer mechanism in active screen cage plasma nitriding process is proposed
میں اور دکتور محمود قاہرہ یونیورسٹی سے کبری الجامعہ کی طرف گامزن تھے کہ سڑک کے کنارے ایک ادھیڑ عمر کا آدمی دیکھا جس کا چہرہ غربت اور معاشی بد حالی کا منہ بولتا ثبوت تھا ۔ موصوف سڑک پر جھاڑو لگا رہا تھا اور بہت سارا کچرا اس کے ناتواں ہاتھوں سے زیادہ کمزور تیلی دار جھاڑو سے اس طرح واپس نکل رہا تھا جس طرح ارنسٹ ہمینگوے کے ناول ’’اولڈ مین اینڈ سی ‘‘ کے مرکزی کردار مچھیرے کے سمندر میں پھینکے ہوئے جال سے نکلتا ہوا پانی ۔میں نے دکتور محمود کو کہا تمھاری حکومت اس آدمی کو جتنی تنخواہ دے رہی ہے اس میں ایسے ہی کام کی گنجائش نکلتی ہے ۔ مصر کی معاشی حالت اور یہاں کے مزدور کی اوقات کی تلخی کو مدِ نظر رکھ کر میں نے پوچھا کہ تمھارے حکمران بھی تو ساٹھ عشرے میں اشتراکی تھے ، جواب دیا جی بالکل ۔اس نے کہا روس سے مراسم ہی کی وجہ سے یہا ں پر پین عرب ازم اور مصری تہذیب کو زیادہ اجاگر کیا جاتا رہا ہے ۔میں نے کہا شاید اس لیے یہاں کے چوراہوں پر ابوالہول براجمان ہے اور پوری مصری قوم اس آس پر بیٹھی ہے کہ پنجوں پر کھڑا ابوالہول ایک نہ ایک دن اٹھے گا اور مصر ترقی کی شاہرہ پر گامزن ہو گا اور صرف یہ نہیں بلکہ مصریوں کے بیٹوں کو قتل کر نے والے رعمسیس کے نام پر ایک بڑی شاہرہ اور چوک کے نام بھی قاہرہ شہر میں رکھے گئے ۔ دکتور محمود مصر کے سیاسی حالات سے گفتگو کو موڑتے ہوئے مجھ سے پوچھتے ہیں کہ اشتراکیوں کی زندگی کیسے گزرتی ہے ۔میں نے کہا آئیڈیل کی تلاش میں گھٹ گھٹ کر ۔میں نے بات پھر مصر کی طرف...
‘Adl and Qisṭ is indeed a manifestation of God’s mercy, rather, it may also be seen as a principal objective of Shariʿah. The origin or sources of administration of justice in Islām are the Quran, Sunnah of the holy Prophet, consensus of opinions of the jurists of Islamic jurisprudence and Analogy (Qiyās). Justice is a sacred obligation of supererogatory. It is obligatory upon the Muslim rulers to appoint judges for the dispensation of justice to attain equality, to protect the human rights from their violation, to safeguard the lives and properties, and to maintain law and order in society. As a judge is supposed to accomplish a very important and noble task being a regent of Allāh, hence, some vital merits and criteria regarding the conditions and qualifications for the appointment of the Qāḍī or judge in the light of the Qur’ān, Sunnah and Islamic jurisprudence and the code of conduct for the Pakistani judges must be observed at all costs. The author of this paper has discussed these conditions and qualifications in this article. There are some unanimous conditions for the appointment of judges, while some others are not agreed upon. While presenting the difference of opinions of the Islamic jurists, the author tried to explain, reconcile the opinions and at some places presented her own view in the light of her analysis and arguments. These conditions are around thirty, but the author according to her own discretion chose some of the most important ones to discuss in this paper.
The work in this dissertation describes the bioassay-guided isolation, and structure elucidation of sixteen compounds isolated from the fruit part of Aristolochia indica Linn. The dichloromethane, and butanolic fractions of the plant material exhibited activities against prostrate (PC-3), and cervical (HeLa) cancer cell lines. The dichloromethane fraction afforded three new compounds, including aristoloquinone (1), aristolocenone (2), and aristoloanoide (3), while the known compounds were identified as dshamirone (4), chrysophanol (5), 4,8-dihydroxy-6-methoxy-2-methylanthraquinone (6), b -sitosterol (7), oleanolic acid (8), ursolic acid (9), 2-(hydroxymethyl)-3 O furaldehyde (10), hydroquinone (11), and 4 -(acetoxy) phenyl acetate (12). The butanolic fraction of the plant yielded three new constituents, aristoloside A (13), aristoloside B (14), and aristoloside C (15), along with a known compound which was identified as butyl 3-O-β- D-glucopyranosyl-(3R), 4-dihydroxy-butanoate (16). The structures of these constituents were elucidated by using modern spectroscopic techniques, including UV, IR, MS, 1D, and 2D-NMR. HO The isolated compounds were tested for their in vitro cytotoxicity against cancer cell lines. Compounds 8, 9, and 11 showed high sensitivity towards the cervical and prostrate cancer cell lines, as compared to the standard drug, doxorubicin. The other natural/ synthetic compounds were also evaluated for their antitumor activity. Among the natural compounds, physalin derivatives showed a potent activity, whereas among synthetic compounds, organotin (IV) carboxylate, and imidazole derivatives exhibited an excellent activity against the cancer cell lines.