In this study, polymer/silica hybrid compositeswere developed using grafting techniques for potential applications as adsorbent, heterogeneous catalyst, and ion exchange resin. Two commonly used grafting techniques i.e., radiation-induced grafting and emulsion graft polymerization have been explored to modify the surface of the commercially available silica microparticles with different monomers to fabricate composite materials for environmental applications. The mesoporous silica particles with high surface area, tunable pore size, and narrow pore size distribution were modified by treating with vinyltriethoxysilane to introduce polymerizable vinyl functionality on the particle surface for in-situ polymerization of various monomers to achieve polymer/silica hybrid composites. Silica/poly(acrylonitrile) and silica/polystyrene hybrid composites were fabricated by in-situ grafting of acrylonitrile (AN) and styrene (St), from surface of the modified silica (MS) microparticles, respectively. Radiation induced grafting was achieved by using the Co-60 irradiator. Systematic and detailed studies have been carried out to investigate the influence of various grafting parameters, i.e., gamma absorbed dose and monomer concentration, on the grafting of acrylonitrile. Under the optimized conditions of 1:12 silica to monomer ratio (w/v) and 20 kGy absorbed dose, afforded the highest grafting (748 %, the value indicates the % increase in weight of the silica particles after the AN grafting). Radiation induced grafting in a solvent free system provided eco-friendly route by avoiding hazardous organic solvents. The emulsion graft polymerization AN was carried out with potassium persulfate as initiator and tween 80 as surfactant in aqueous medium. Systematic investigations were carried out to elucidate the effect of monomer, initiator, and surfactant concentration on the grafting. The optimized conditions were found to be 6% monomer, 0.15 % initiator, and 1 % surfactant concentration that afforded the highest grafting (296 %). The nitrile (-CN) groups of the grafted poly(acrylonitrile) were converted into amidoxime functionality by treating with hydroxylamine. The emulsion grafting route is free from the requirements of using higher monomer concentration, costly organic solvents, and special equipment. In 2nd study, styrene was grafted onto modified silica particles to afford silicagrafted-styrene composite via radiation induced grafting and subsequent sulfonation of the grafted polystyrene. The effect of grafting conditions, such as absorbed dose, monomer concentration, and the type of solvent used was investigated in detail. The structural and morphological investigations of the hybrid composites were carefully performed by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) nitrogen adsorption-desorption isotherms. The amidoxime grafted silica materials prepared were evaluated as adsorbent for Cu(II) ions from the aqueous solution and were found to have higher loading capacities of 172 mg/g and 130 mg/g, respectively, for radiation-induced and emulsion grafted samples. The hybrid materials after loading with Cu(II) ions were also employed as heterogeneous catalyst for the reductive degradation of methylene blue (MB) in the presence of NaBH4 as reductant. The reduction process followed pseudo-first-order kinetics and the rate constant (k) was calculated 0.6224 min-1. The hybrid catalyst was found to be highly effective for the degradation of MB and can be easily recovered and reused several times with no appreciable loss of catalytic activity. The ion exchange capacity (IEC) of the fabricated silica-grafted-sulfonated styrene composite resin was evaluated by ion exchange titrations (back titration method). The IEC was found to be in the range of 0.43-2.97 meq/g depending on the degree of grafting. The facile fabrication method and high IEC value could lead to potential application of the fabricated resin in ion exchange resin in waste water treatment and metal recovery.
ریاض الدین احمد علمی اور تعلیمی حلقوں میں جناب ریاض احمد صاحب کی وفات سے جو خلا ہوا ہے اس قحط الرجاں میں اس کا پرُ ہونا مشکل ہے۔ ان کا اصل وطن غازی پور تھا۔ لیکن وہ الٰہ آباد میں متوطن ہوگئے تھے۔ انہوں نے مجیدیہ اسلامیہ انٹر کالج کے نیک نام اور کامیاب پرنسپل کی حیثیت سے بڑی شہرت و عزت حاصل کی وہ طلبہ کی ذہنی و دماغی اور علمی تربیت بڑی دلسوزی سے کرتے تھے، ان کے زمانے میں کالج کا معیار تعلیم بہت بلند تھا، ان سے فیض حاصل کرنے والے طلبہ کی تعداد بے شمار ہے۔ ریاض الدین احمد صاحب کا خاص مشغلہ درس و تدریس تھا لیکن انہیں علم سے شغف اور تحریر و تصنیف کا اچھا ذوق تھا، طلبہ کی درسیات کے لیے متعدد کتابیں لکھیں جو مقبول ہوئیں، سائنس ان کا خاص موضوع تھا، اس پر جو کتابیں لکھیں وہ مدارس کے طلبہ کے لئے خاص طور پر مفید ہیں، قرآن مجید کے درس و تعلیم کا اچھا منصوبہ بنایا تھا۔ ان میں بڑی دینی و ملی غیرت تھی، مسلمان بچوں کو اپنے عقیدہ و مذہب پر استوار اور ملی شناخت باقی رکھنے کے لیے انہوں نے ایمانی پرائمر وغیرہ کے نام سے کئی مفید کتابیں لکھیں۔ قدرت نے انہیں درد مند دل اور بے چین طبیعت عطا کی تھی، وہ قوم و ملت کی فلاح کے ہر کام میں پیش پیش اور مسلمانوں کی ترقی و سر بلندی کے لیے برابر فکرمند رہتے مجلس مشاورت اور دینی تعلیمی کونسل سے شروع ہی سے وابستہ رہے، دینی تعلیمی کونسل کے جلسوں اور کانفرنسوں میں دلچسپی سے شریک ہوتے تھے، ایک دفعہ اس کی ایک بڑی کانفرنس اعظم گڑھ میں ان کی صدارت میں ہوئی، ان کا خطبہ صدارت اور قاضی محمد عدیل عباسی کی اہم تقریر کو...
Penelitian ini bertujuan untuk mengetahui peningkatan keaktifan dan hasil belajar siswa pada mata pelajaran Pendidikan Agama Islam (PAI) setelah diterapkannya metode pembelajaran demonstration berbasis discussion process. Metode penelitian yang digunakan dalam penelitian ini adalah Penelitian Tindakan Kelas (PTK). Penelitian dilakukan di SMA EKASAKTI Padang pada kelas XI. Metode pengumpulan data yang dilakukan pada penelitian ini adalah: observasi, wawancara, dokumentasi, dan tes. Analisis data dalam penelitian ini dilakukan secara deskriptif kuantitatif dan kualitatif. Hasil dari penelitian ini adalah: (1). Kesiapan siswa dalam menerima pelajaran sebelum dilakukan tindakan 39, 06%, setelah siklus I 70, 31%, dan setelah siklus II 86, 23%. (2). Keaktifan siswa dalam proses pembelajaran sebelum dilakukan tindakan 23, 18%, setelah siklus I 67, 97%, dan setelah siklus II 85, 41%. (3). Persentase siswa yang mendapatkan nilai tuntas di atas 70 sebelum dilakukan tindakan 31, 75%, setelah siklus I 68, 25%, dan setelah siklus II 87, 75%. (4). Terdapat peningkatan yang signifikan antara masing-masing indikator pada setiap siklus, hal tersebut dapat di lihat dari peningkatan kesiapan, keaktifan, dan hasil belajar siswa pada saat sebelum dilakukan tindakan, pada siklus I dan pada siklus II. Pada siklus II semua indikator telah melampaui target persentase indikator keberhasilan yang telah ditetapkan. Sehingga siklus penelitian dapat dihentikan pada siklus II dan dapat di tarik kesimpulan bahwa metode pembelajaran demonstration berbasis discussion process berhasil serta lebih efektif dibandingkan dengan metode ceramah.
Studies to evaluate selenium (Se) supplementation through various application methods for its enrichment in bread wheat (Triticum aestivum L.) were conducted in the Seed Science Laboratory and Agronomic Research Area, Department of Agronomy, University of Agriculture, Faisalabad, Pakistan. Initially, two laboratory studies were conducted to optimize the rate of Se supplementation for seed priming and seed coating of two wheat cultivars Shafaq-2006 and Lasani-2008. Laboratory experiments were carried out in a completely randomized design in factorial arrangements and replicated thrice. In an initial field study, the impact of exogenous Se supplementation by various methods on the enrichment of two local bread wheat cultivars was undertaken while in a second experiment, grain enrichment potential through foliage applied Se on wheat cv. Lasani-2008 was investigated. Both field experiments were carried out in randomized complete block design in a factorial arrangement having a net plot size of 2.7× 6.0 m with three and four replications respectively. Results of the laboratory priming experiment revealed that seeds primed in 0.125 mM and 1.25 mM Se priming solution gave a significantly improved stand establishment and seedling growth rate as exhibited by a substantial reduction in the time to undertake 50% emergence (T50) and the mean emergence time (MET) as compared to other treatments. In the second laboratory trial, coating of 1 kg of wheat seed with either 1.5 or 1.0 g Se considerably improved the early emergence, which in turn resulted in a healthy seedling stand establishment and better growth of seedlings of both wheat cultivars studied. In the first field study, Se supplementation by foliage feeding (100 g ha-1 or 50 g ha-1) significantly improved spike length, number of spikelets spike-1, number of grains spike-1, the number of productive tillers m- 2, 1000-grain weight, biological yield, grain yield and harvest index of both wheat cultivars and during both years of the study. However, non-significant variation in plant height for both varieties was recorded with Se nutrition. Maximum Se enrichment was observed in grains of wheat cv. Lasani- 2008 when treated with foliar feeding of 100 g Se ha-1. Lasani-2008 showed better potential for accumulation of Se in grains as compared to Shafaq-2006. Results of the second field study revealed that different sources of Se supplementation, applied at different growth stages, significantly affected the growth and yield of wheat. Maximum grain yield was attained with foliar spray of sodium selenate at booting stage. In contrast, Se foliage sprays applied at anthesis (flowering) caused significantly higher accumulation of Se in wheat grains as compared to all other treatments. In first field trial, Se application through seed priming, at the rate of 0.125 mM showed the maximum net benefit while in the second field study; maximum net benefit was obtained with the Se foliar spray at the booting stage of growth.