Organic materials have attracted remarkable interest in the field of electronics due to good me- chanical stability and semiconducting and conducting properties. Organic semiconductors have the advantage of large area fabrication and low temperature deposition. Hence, low cost electronic de- vices can be easily fabricated over large scale by employing organic materials. The stated features assure organic materials as prominent candidates for the development of organic electromechani- cal sensors. The aim of this work was to study the applicability of organic materials for various electromechanical sensors. In this research work, thin films of various organic semiconducting ma- terials and composites were employed for the development of organic field effect transistor (OFET) and sensors to investigate their electromechanical properties. In this dissertation, the organic materials investigated were copper phthalocyanine (CuPc), poly-N-epoxypropylcarbazole (PEPC), nickel phthalocyanine (NiPc) and carbon nanotubes (CNTs). Inorganic materials, vanadium oxide (VO 2 ) and cuprous oxide Cu 2 O were also investigated and used in making composites for altering the properties of devices. CuPc was employed in fabrication of OFET by vacuum evaporation method. The OFET was then characterized for pressure and displacement sensing properties. The variations in drain to source resistance were measured for applied pressure and change in displacement, respectively. PEPC microcomposite thin films were drop-casted on a variety of substrates to fabricate sand- wich type sensors. The different substrates used were aluminium, steel, plastic and glass (with prefabricated electrodes). The substrates in this study served dual purpose, i.e., serving as an elec- trode and providing mechanical support to the device. The sensors were investigated for applied pressure and change in displacement. The measurements were made for different concentrations of composites and for different thicknesses of thin films. The variations in resistance and capac- itance of the transducer were observed with the applied stimuli. In the first case, Cu 2 O-PEPCii microcomposites were used to develop pressure sensor. The thicknesses of the films were in the range of 30 − 100μm. The AC resistance and capacitance at 120 Hz of the transducer decreased by 1.1 ∼ 1.4 and increased by 1.2 ∼ 1.8 times respectively as the pressure was increased up to 100 kN m −2 . Afterwards, V 2 O 4 -PEPC microcomposites were used to develop another pres- sure sensor. The thickness of the V 2 O 4 -PEPC films were in the range of 20 − 40 μm. The DC resistance of the sensor decreased on average by 24 times as the pressure was increased up to 11.7 kN m −2 . Finally, Cu 2 O-PEPC-NiPc microcomposites were used to develop pressure sensor. The film thickness of the composite was in the range of 20 − 30 μm. The decrease in resistance of the sensor was observed 10 times by increasing the external uniaxial pressure up to 11.7 kN m −2 . In case of displacement sensor, Cu 2 O-PEPC microcomposites were used to fabricate displacement transducer. The thicknesses of the films were in the range of 50 − 60 μm. As the displacement from 0 − 0.6 mm, the decrease in sensors DC resistance was observed as 1.5 times to the initial resistance, and accordingly, the increase in AC capacitance (at 120 Hz) was measured 2.31 times to the initial capacitance by applying the displacement in the range of 0 to 1.3 mm. Furthermore, the CNTs based Al/CNT/Al sandwich type sensors were investigated. Sensors were fabricated by deposition of the CNTs on the adhesive elastic polymer tape and placing it in the elastic casing. The resistance-pressure and resistance-displacement relationships were determined to ensure the piezoresistive properties of CNTs. The diameter of multiwalled nanotubes (MWNTs) varied between 10 − 30 nm. The nominal thicknesses of the CNTs layers in the sensors were ∼ 300 − 430 μm. The interelectrode length (gap) and width of the sensors were in the range of 4 − 6 mm and 3 − 4 mm, respectively. In investigation of the pressure sensor, the decrease in DC resistance was noted as 3 − 4 times as the pressure was increased up to 17 kN/m 2 , whereas the DC resistance of the displacement sensors from different batches was decreased in average by 3 times as the displacement was increased up to 900 μm. Finally, measurements were made on CNT-Cu 2 O composite as a strain sensor. The press-tablets of the composite were fabricated and glued on the flexible elastic beam. The electromechanical properties of the sensors were measurediii under compression and tension. The inter-electrode length (gap between the contacts) and width of the samples were in the range of 6 − 8 mm and 10 mm, respectively. The variation in DC resistance of the transducers were observed under compression and tension. It was noted that the resistance decreases 24 − 28 times under compression while increases 44 − 46 times under tension. The resistance-strain relationships were also simulated.
(پی ایچ۔ڈی سکالر شعبہ اُردو، منہاج یونیورسٹی لاہور)
عرب ممالک میں اُردو سے محبت کرنی والی ایک ایسی شخصیت موجود ہے جنہوں نے ایم۔اے اُردو، پھر ڈاکٹریٹ کی ڈگری بھی اُردو میں حاصل کی۔مصر سے تعلق رکھنے والی عرب نژاد اُردو شاعرہ، افسانہ نگار ،کالم نگار، سفر نامہ نگار ڈاکٹر ولا جمال العسلی ہیں ۔
ڈاکٹر ولا جمال نے پی ایچ۔ڈی کی ڈگری کے حصول کے لیے مقالہ بہ عنوان "فہمیدہ ریاض کی شاعری "لکھا۔اس وقت عین شمس یونی ورسٹی مصر کے شعبہ اُردو میں تدریسی خدمات سرانجام دے رہی ہیں ۔
مادری زبان عربی بولنے والی ڈاکٹر ولا جمال کی اُردو سے والہانہ محبت ہم اُردو والوں کے لیے ایک قابل فخر بات ہے۔وہ اُردو سے پیار کا اظہار کچھ یوں کرتی ہیں :
اس کے ہر لفظ میں ہے اس لیے سمٹی خوشبو
دختر نیل کی سانسوں میں گھلی ہے اُردو
یہ شعر ان کی کتاب "دخترِ نیل " میں بہ طور انتساب شامل ہے۔اسی کتاب کے پیش لفظ میں وہ اُردو سے پیار کا اقرار کچھ یوں بھی کرتی ہیں:
"میں اُردو سے عقیدت کی حد تک محبت رکھتی ہوں ۔اُردو کے لیے خود کو وقف کر دیتی ہوں ۔اپنی زندگی میں اسے سب سے زیادہ اہمیت دیتی ہوں۔"(پیش لفظ:ص14)
نے اُردو سے اپنی محبت کا ثبوت کچھ اس طرح دیا ہے کہ متنوع اور فکر انگیز موضوعات کو مختلف اصناف میں طبع آزمائی کرکے پیش کیا ہے۔لیکن ان کی وجہ شہرت شاعری بن چکی ہے۔ان کا شاعری کا پہلا مجموعہ "سمندر ہے درمیان" کے نام سے شائع ہوا، یہ...
The study aimed to analyze lexical items underpinned in the textbooks used in the current teaching of ESP and GE. Using content analysis, a systematic evaluation of texts to examine nuances to bridge the gap between quantitative and qualitative data. This was such of importance, however, difficult to study due to issues of interest like in the study, frequency of lexical items in ESP, and GE textbooks. Results found 13,713 lexical items in Hospitality Management, 17,561 in Criminology, 4576 in Tourism, 7167 in Marine Engineering, and 512 in Information Technology. Furthermore, the overall percentage of ESP lexical items fell in Tier 2 (with multiple-meaning while the least was in Tier 3, specifically on context-specific vocabulary. It is the core of vocabulary learning to ensure English language teaching. It is its goal to help learners better understand language, allowing them to understand others as they want to express themselves as well. This applies not only in speaking but also in writing and reading. Wilkins (1972, p. 111-112) stated that without grammar very little understanding can be acquired and without vocabulary there can be no learning at all. Thus, even without good grammar, so long as you equipped with useful words and expression, one can still manage to communicate. Lewis (1993) argued that “lexis is the heart of language” and that it develops a better fluency and expression in English. He also added the significance to the learners of acquiring a more productive vocabulary knowledge, also, their eagerness to develop their own personal vocabulary strategies. Thus, a proposed bridge model program was recommended to highlight the study findings using the lexicons found from the different respective courses.
Apricot (Prunus armeniaca L.) is a highly nutritious fruit with a variety of bioactive health promoting components. In the first experiment, among the tested varieties, Habi extracted with 80% methanol maintained the higher total phenolic contents, flavonoid contents, radicle scavenging activity and were equally good in regards to antibacterial potential against Escherichia coli, Salmonella entritidis, Pseudomonas flourescens and Helicobacter pylori. These collected extracts were then examined against different solvents. Similar trend was also observed in TPC, TFC, DPPH activity and antimicrobial activities against tested bacteria with butanol extracts of the Habi variety. In the second experiment, comparatively a higher TPC, TFC and DPPH activity was recorded in 4 hrs of extraction time with 40oC temperature at deep orange stage. Similar trend was also recorded in regards to antibacterial activities against tested pathogen respectively. The results also confirmed the higher potential of butanol then other counterparts indicating the maximum values of TPC, TFC and DPPH activity and antibacterial activities against four tested pathogens. In the third experiment, the spectrum of FTIR spectroscopy confirmed the presence of polyphenolic compounds in these extracts. HPLC analysis revealed presence of various bioactive compounds especially chlorogenic acid in butanol extract. These fractions also showed a significant antibacterial activity against four pathogens. This organism showed sensitivity to a dose of 20 μg/ml. It was further found that about 8.4 and 3.8 μg/ml of CA was present in one fruit on fresh and dry weight basis. Finally, H. pylori positive patients were identified followed by a dose of fresh and dried Habi variety to male and female patients for the period of 20 days. Later on, the results suggested that three dried apricots showed promising effects in the urease (up to 37.5%) and IgG (15.8%) of positive patients. So, three dried apricots (approx. 15 gm) are recommended for eradication of infection.