بزدل قوم کا بہادر لیڈر
4اپریل 1979ء کو بھٹو صاحب کو گڑھی خدا بخش دفن کر دیا گیا ۔6اپریل کو فوج کا پہرہ ختم ہوا تو پاکستان پیپلز پارٹی کے قائدین فاتحہ خوانی کے لیے گئے ۔ان میں بھٹو کے وکیل یحیٰ بختیار بھی تھے جب گائوں پہنچے تو لوگوں نے انہیں گھیر لیا اور پوچھنے لگے آپ تو ہمارے لیڈر کے سب سے قریب تھے ۔آخری وقت انہوں نے کوئی پیغام دیا یا کچھ کہا ۔یہ سن کر یحییٰ بختیار کی آنکھوں میں آنسو آگئے اور بولے بھٹو صاحب نے آخری ملاقات میں مجھ سے کہا ’’بزدل قوموں کے بہادر لیڈروں کا یہی انجام ہو تا ہے ‘‘
Electrical energy is the most efficient and the cleanest form of energy at the moment that is being transmitted and distributed amongst end-users. From its earlier days, the AC system was preferred as an economical solution for transmission and distribution. However, the development in the power electronics technology and the evolution of highly efficient power electronic converters have established the resurgence of DC power system. Furthermore, the trend is shifting towards DC loads as various energy efficient appliances, such as DC inverter air conditioners, operate on DC nowadays. This further advocates the shift towards the DC power system. This research works is an effort to perform the comparative analysis of AC Distribution System (ACDS) and DC Distribution System (DCDS), with regards to power quality and harmonic distortion in particular. The comparison is performed considering load profile and load variation on daily basis. Simulations are performed in MATLAB. It has been concluded at the end that ACDS is better than DCDS in terms of power quality as total harmonic distortion of the DCDS under the same loading and same load variation during the whole day was significantly higher than that of ACDS.
Present study complies with different principles of green chemistry utilizing efficient instrumental techniques i.e; microwaves, ultrasonic waves and replacement of hazardous solvents with greener ones. The overall progress of chemical reactions achieved through application of green chemistry, was compared with the traditional methods. In the first part of this research work, synthesis of N’-benzylidene-2-(2-fluorobiphenyl)propanehydrazides was carried out for which, 2-(2-fluorobiphenyl-4-yl)propanoic acid was esterified to methyl 2-(2- fluorobiphenyl-4-yl)propanoate under the influence of microwaves followed by its hydrazinolysis. 2-(2-Fluorobiphenyl-4-yl)propanehydrazide thus obtained, was then reacted in an ultrasonic bath with different benzaldehydes to get a series of N’-benzylidene-2-(2- fluorobiphenyl)propanehydrazides. In the second series, 2-(2-fluorobiphenyl-4-yl)propane hydrazide was converted to 4-amino-5- [1-(2-fluoro-biphenyl-4-yl)-ethyl]-4H-[1,2,4]triazole-3-thiole followed by its reaction with different benzaldehydes under conventional and green technologies to get a series of 4- (benzylidene-amino)-5-[1-(2-fluorobiphenyl-4-yl]-4H-[1,2,4]triazole-3-thiole compounds. In another series, different substituted chalcones were prepared by clasian condensation method which were then reacted with 2-(2-fluorobiphenyl-4-yl) propane hydrazide in a mixture of water and ethanol to get a series of 2-(2-fluorobiphenyl-4-yl)-propionic acid(1,3- diphenyl-allylidene)-hydrazide. These reactions were conducted utilizing green technologies and were compared with using conventional methods. Comparison of both the conventional and microwaves/ultrasound assisted reactions indicates a significant reduction in reaction times and improvement in reaction yields. Besides, chemical characterization and X-ray crystallography of selected compounds, all the synthesized compounds were evaluated for their anti-oxidant potential [Total anti-oxidant activity, ferric reducing anti-oxidant power (FRAP) and total phenolic contents], and analgesic activities using (tail flick, hot plate and writhing methods) and most of them were found to possess potential as lead compounds for drug discovery.