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Synthesis and Characterization of Polyethylene Composites Based on Polysaccharide

Thesis Info

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Author

Mir, Sadullah

Program

PhD

Institute

Quaid-I-Azam University

City

Islamabad

Province

Islamabad.

Country

Pakistan

Thesis Completing Year

2011

Thesis Completion Status

Completed

Subject

Chemistry

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/1511

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727461287

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Some novel biodegradable polymer composites were synthesized, using polyolefin as a matrix with various natural polymers including chitosan, starch and carboxymethyl cellulose as biodegradable additives. The compatibility of the components was enhanced with different silane coupling agents. The materials were heat mixed in brabender plasti- corder mixer using roller rotor. During mixing, different temperatures were used to mix and decompose the initiator to start the grafting of silane and crosslinking of the polymer. The blended materials were hot pressed into sheets. The hydrolysis and the condensation reactions of silane were carried out in hot water at 95°C for 20 hours. After crosslinking reactions, the prepared sheets were dried in vacuum oven for 16 hours before characterization. The structural analysis of the non-crosslinked and crosslinked composites was carried out using Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM) techniques. The crosslinking reaction was confirmed by FTIR spectra, which revealed the important absorption peaks of siloxane (Si-O-Si) and Si-O-C bonds. SEM images also revealed that crosslinking has improved the dispersion and interaction between polymer and the additives. The degree of crosslinking as determined by gel content analysis was found to be directly proportional to the amount of chitosan in HDPE/chitosan composite. In LLDPE/starch/sepiolite composite, it decreased with high sepiolite loading. Thermogravimetric analysis showed higher thermal stability of the crosslinked composites. Differential scanning calorimetry showed decreasing trend of percentage crystallinity with increasing amount of additive. This behavior is associated to the network structure and the disorder of close packing of polyethylene chains. Rheological studies of crosslinked composites showed linear viscoelastic behavior with high complex viscosities (h*) and dynamic shear storage moduli (G`) reflecting a strong interaction between matrix-filler interphase and the elastic nature of the crosslinked samples. High tensile strength (TS) and reduced elongation at break (Eb) values were observed in all the crosslinked samples of HDPE/chitosan and HDPE/carboxymethyl cellulose composites. However, the TS and Eb values of non-crosslinked and crosslinked formulations for LLDPE/starch/sepiolite composite showed decreasing trends with high starch and sepiolite loading. Creep experiments indicated a small deformation in crosslinked composites, which showed that silane effectively coupled the immiscible components.
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چوتھا باب: کتب مقدسہ

تنخ

باب چہارم کے اہم نکات

  1. یہودی کتب مقدسہ کا تعارف۔
  2. مصنفہ و زبانی قانون میں فرق۔
  3. عبرانی بائیبل اور اس کے تراجم کا تعارف، تاریخ اور اہمیت۔
  4. مشنا، جیمارا ور تلمود کا تعارف۔
  5. ہلاخا کی تاریخ و اہمیت۔
  6. اپاکرفا، مدراش، زوہر اور سیدور کا تعارف۔

 

مذہبی یہودی اس بات پر یقین رکھتے ہیں کہ ان کی رہنمائی کے لیے خدا نے متعدد کتابیں نازل کیں۔ یہ کتب خدا کے الفاظ ہیں جو مختلف ادوار میں مختلف انبیا و رسل پر نازل ہوئے۔ چنانچہ وہ ان کتب کو یہودی مذہب کی بنیاد مانتے ہیں۔ یہودیوں کے تمام فرقے ان کتب کی عزت کرتے ہیں، تاہم معنی اخذ کرنے اور تشریحات میں دیگر مذاہب کے پیروکاروں کی طرح ان میں بھی اختلاف پایا جاتا ہے جو مذہبی نقطہ نظر سے کافی اہمیت کا حامل ہے

 

 دریائے نیل کے کنارے اگنے والے نرسل کی طرح کے پودے سے بنائے گئے کاغذ جسے پیپرس/پپائرس/قرطاس مصری کہا جاتا ہے یا جانوروں کی چمڑی سے بنے کاغذ پر انہیں مختلف ادوار میں مختلف لوگوں نے لکھا۔ ہاتھ سے لکھی جانے والی ان کتب میں کاتبین نئے مشمولات بھی شامل کرتے رہے، مثلاً "کتابِ یسعیاہ" چونکہ تین مختلف ادوار سے متعلق ہے اس لیے کہا جاتا ہے کہ اسے تین مختلف لوگوں نے لکھا ہے۔ زیادہ تر محققین کا خیال ہے کہ تقریبا 400 قبل مسیح تک ان کتب کی تکمیل ہوتی رہی ہے۔[1] ان میں سے بیشتر کتب کی زبان عبرانی ہے جبکہ کچھ کتابیں آرامی زبان میں بھی لکھی گئیں ہیں۔ آرامی ذخیرہ الفاظ میں عبرانی سے ملتی جلتی ہے لیکن گرائمر اور لغوی اعتبار سے مختلف ہے۔۔ جلاوطنی سے پہلے تک یہ کتب...

مولانا ابو یوسف محمد شریف محدث کوٹلوی کی خدمات حدیث شریف

In this paper, based on the primary sources, an attempt has been made to discuss the contribution and services of Mawlānā Abū Yūsuf Muḥammad Sharīf (d. January 1951) commonly known as Faqīh-i-Ā‘ẓam and Muḥaddith-i-Koṯalwī in the field of Ḥadīth, the second most important source of Islamic Law. Mawlānā Muḥaddith-i-Koṯalwī having a deep insight in the Science of Ḥadīth has written extensively on this facet of Islamic learning. Mawlānā Abū Yūsuf Muḥammad Sharīf Muḥaddith-i-Koṯalwī through his fatāwā, articles, sermons and books done a great service for the Science of Ḥadīth. He has explained the five pillars of Islam and other rituals in the light of different āḥādīth. Being a Ḥanafī ‘ālim, Mawlānā Muḥaddith-i-Koṯalwī also proved that the Fiqh-i-Ḥanafī, the most popular fiqh among the South Asian Muslims, is in accordance with the authentic āḥādīth. He has also discussed the difference between a Ḥadīth and Sunnah.

The Relationship Between Environmental Beliefs and Green Purchase Intentions: Examing the Mediating Role of Environmental Concern and Moderating Role of Environmental Responsibility

The voice of environmentally concerned consumers led many firms to incorporate the green marketing elements in their business models. Many organizations spent millions of dollars on the development, selling and promotional campaigns of green products. The notion was also supported by researchers and international survey organizations in the form of growing demand and market share of green products. However, in reality, existing sales trends of green products in the markets are not promising. Although consumers are in favor of green products and green firms even some of them are agreed to pay extra amount to buy green products but when comes to make a purchase decision, conventional products remain their first choice at the point of sale. Thus, non-acceptance of green products by the consumers at large scale is becoming a major issue of concern for marketing managers. Therefore, it is very timely to explore and understand the underlying mechanism of human attitude formation process. The aim of this research is to examine the impact of environmental beliefs on green purchase intentions. Although, environmental beliefs have a significant role in motivating the individuals to behave in an environmental friendly way still a weak relationship between environmental beliefs and green purchase intentions has been reported in prior research. Therefore, the mediating role of environmental concern between environmental beliefs and green purchase intentions as well as moderating role of environmental responsibility between environmental beliefs and environmental concern was explored to advance the existing stream of research in the field of green marketing. The conceptual framework was developed based on the theory of reasoned action. Survey method was used to collect data from consumers of Rawalpindi and Islamabad. For this purpose, already established measures were adapted from xi previous studies in the field of green marketing. Subsequently, 519 useable responses were utilized for data analysis through statistical techniques. Structural Equation Modeling (SEM) technique was used to gauge the model fit and to test the hypothesized associations. Likewise, the conceptual framework was also tested through bootstrapping technique suggested by Preacher and Hayes. The results revealed that environmental concern mediate the relation between environmental beliefs and green purchase intentions. Similarly, moderating role of environmental responsibility between environmental beliefs and environmental concern was also proved. The thesis was winded up by highlighting the theoretical, contextual and managerial implications along-with future research avenues.