Cobalt ferrite, having an inverse spinel structure and the inherent properties of high coercivity, moderate saturation magnetization and high electrical resistivity, is a potential candidate for magnetic storage devices and high frequency applications. In the present study, cobalt ferrite has been doped with various dopants like Cr, rare earths (Sm, Ho, Er, Dy and Pr) and Zr co-doped with Mg, Mn and Ni, in order to improve the electrical and magnetic properties while maintaining a spinel structure and moderate saturation magnetization values a micro-emulsion method of preparation in which a cheap surfactant, namely polyethylene glycol, has been used. The formation of spinel phase occurs between 573 and 673K as indicated by the thermal analyses (TG/DTA), but a well crystalline and stable spinel phase is achieved at 1073K as evident from the powder X-ray diffraction studies of the synthesized samples. All the doped cobalt ferrite samples are in single spinel phase as confirmed by XRD and magnetic susceptibility measurements. The average crystallite sizes of the doped cobalt ferrite samples are in the range of 13 nm to 70 nm. The elemental composition of doped cobalt ferrites is confirmed by energy dispersive X-ray fluorescence analysis which shows an agreement between the theoretical and experimental compositions of the prepared samples. Electrical resistivity as measured at 293K the by two point probe method is found to have a value of 1.25 × 106 Ωm for un-doped cobalt ferrite which is enhanced by doping with Cr, Zr-Mg, Zr-Mn and Zr- Ni. For small contents of rare earth metal cations introduced into spinel lattice of cobalt ferrite the electrical resistivity (at 293K) increases to a larger extent due to insulating nature of rare earth oxides. The variation in electrical resistivity with composition and temperature has been discussed on the basis of hopping model of electron conduction in ferrites. The activation energy of hopping and drift mobility of the charge carrier is calculated from the resistivity data. The dielectric properties are measured by inductance capacitance resistance (LCR) meter in the frequency range of 100Hz – 1MHz and dielectric constant (έ), dielectric loss angle (tanδ) and dielectric loss factor ( ε ′′ ) are calculated from the capacitance data. These dielectric parameters are found to decrease with increasing frequency. This behaviour is typical of ferrites as explained by Koop’s model. The dielectric constant (έ) and the dielectric losses of the un-doped cobalt ferrite have been reduced by doping in the present work. Curie temperature has been determined from the low field AC-magnetic susceptibility measurements and was found to increase for specific contents of dopants as compared to the un-doped cobalt ferrite while for others a lower value of Curie temperature was observed. Saturation magnetization has been increased by doping with Cr up to x = 0.5, Zr-Mn content x = 0.1, Sm content x = 0.04 and Er content x = 0.08 while for the rest of compositions the saturation magnetization has been decreased as compared to the un-doped cobalt ferrite sample. Beside this, the coercivity of the materials prepared in the present study has been increased by doping rare earth metal cations, while it has been reduced by Cr and Zr co-doped with Mg, Mn and Ni, in cobalt ferrites. The reduction in magnetization has been discussed in terms of dilution of magnetization, crystallite size effects and the spin canting introduced by the dopants at octahedral sites.
اہلیہ، مفتی عتیق الرحمن عثمانی ایک افسوس ناک خبر نہایت افسوس کے ساتھ اطلاع دی جاتی ہے کہ ۲۷/ مارچ ۱۹۸۵ء کی صبح سات بجے حضرت مفتی عتیق الرحمن عثمانی کی اہلیہ کا انتقال ہوگیا۔ تدفین قبرستان مہندیان میں ہزارہا افراد کے درمیان عمل میں آئی۔ حضرت مفتی صاحب کی اہلیہ کی رحلت سے خاندان عثمانی کو زبردست جھٹکا لگا ہے۔ براہِ کرم زیادہ سے زیادہ ایصال ثواب کریں۔ مرحومہ اہلیہ مفتی صاحب بڑی خوبیوں اور بے پناہ صلاحیتوں کی مالک تھیں۔ ادارہ ندوۃ المصنفین کے بہت سے علمی، دینی اور مذہبی و تجارتی معاملات میں حصہ لیتیں اور اپنے مشوروں سے ادارے کو کمک پہنچاتی تھیں جس سے استفادہ حاصل ہوتا اور حضرت مفتی صاحب ان کے اس عمل سے بے حد متاثر ہوتے۔ اگر آپ حضرت مفتی عتیق الرحمن کی اہلیہ کے ابتدائی حالاتِ زندگی پر روشنی ڈالتے ہیں تو وہ جن حالات سے دوچار ہوتی رہیں کس طرح انھوں نے اس کو حسن و خوبی سے نبھایاوہ ہر لحاظ سے بے مثال ہے۔ حضرت مفتی عتیق الرحمن صاحب کے دل میں ان کی خوبیوں کی قدرو منزلت دن دوگنی رات چوگنی برابر مزید بڑھتی چلی گئی اور اہلیہ کی اتنی طویل علالت سے ان کا دل بے حد متاثر ہوتا تھا۔ میری والدہ ماجدہ کی جدائی میرے لیے بہت بڑا سانحہ ہے۔ [عمید الرحمن عثمانی، اپریل ۱۹۸۵ء] ___________________ مفتی عتیق الرحمن عثمانی کی اہلیہ کاانتقال افسوس ہے کہ ۲۷؍ مارچ کوحضرت مفتی عتیق الرحمن عثمانی ؒ کی اہلیہ محترمہ راقم الحروف کی خالہ اماں__ہم سب کو داغِ مفارقت دے گئیں اس طرح ایک ہی خاندان کے تین افراد دس ماہ کے اندر اندر اس دُنیا سے رخصت ہوکررفیق اعلیٰ سے جاملے۔ سب سے پہلے گذشتہ سا ل۱۰؍ مئی کواحقر کی والدۂ محترمہ کے سایہ عاطفت سے ہم محروم ہوئے اس کے...
Hafiz Ibn-e-Kaseer’s ‘Al-Bidaya Wan-Nehaya’ maintains a remarkable position in the field of historiography. In this valuable book, he has described the occurrences of the important nations of the past and the epochs of the previous Prophets up to his own era. Although ‘Al-Bidaya Wan-Nehaya’ is basically a book of ‘History’, yet the worthy author has referred to numerous salient events pertaining to the life and mission of the holy Prophet (SAW). A considerable portion of the book, about two thousand pages, relates to the biograph of the Holy Prophet (SAW). Hafiz Ibn-e-Kaseer’s mode of ‘Seerah-writing’ differs from all other biographers in certain aspects. There are some distinctive marks which distinguish his biography from others. The following Article is an analytic account of the characteristic features and merits as well as deficiencies and shortcomings of ‘Al-Bidaya wan-Nehaya’ with special reference to the science ‘Seerat-Writing’ and it aims at determining its credibility as a source of Prophetic Biography
In higher education, the students face a range of differences in teaching learning environment and academic standards than their prior educational background. This study investigated the relationship of ‘program demand’ with ‘academic self-regulation* and ‘performance’ of university students. The objectives of the study were to determine the relationship of program demand with academic self¬ regulation and to explore the relationship of program demand with academic performance, An intensive review of related literature paved the way towards further exploration of concerned variables. Students of Master’s level in University of the Punjab studying in semester system formed the population of the study. All students (132) enrolled in two Master’s level program (MBA and MERA) were selected as sample for this longitudinal study spread on three academic semesters. Research data were collected using three instruments. They were the questionnaire for teachers regarding Program Demand to assess the demands of the programs, Academic Self- Regulation Scale to measure the degree of self-regulation of the students, and Achievement scores of students to determine correlation between programs, The collected data was imported on SPSS 15.0 and different statistical techniques, i.e., descriptive statistics, l-test, Mann- Whitney Test, Point-biscrial coefficient of correlation, and Pearson product- moment correlation coefficient measures were applied according to the nature of the research questions addressed. Major findings and results of the research explored that MBA program of study was high demanding than MERA program of study on program demand scale but it was intcrestinglyfound that students of low demanding (MERA) program gained more in their self-regulation as academic session progressed, although still remained less sclf-rcgulated as compared to students of MBA in aggregate score, The relationship of program xiiidemand with various faciorsof academic self-regulation was negligible on overall behaviors of male, female, regular and private students. The relationship of academic performance with factors of academic self-regulation varied in strength, direction and significance. The academic performance of students of high demanding program (MBA) was significantly higher than low demanding (MERA) program of study. This correlation was significant, strong and positive from beginning to the end of the study.