Automotive lubricating oils play a most vital role in our great complex civilization. To estimate the importance of its role one need only consider that every moving part of every machine is subjected to friction and wear. Friction consumes energy; wear causes changes in dimensions and eventual breakdown of the machine. To overcome this problem, lubricating oil is used to reduce friction, protect against wear, carry away heat, protect against rust and remove contaminants from the engine. This lubricating oil is made from crude oil after refining by introducing proper additives and its sources and reserves are limited and are not inexhaustible throughout the world. The used oil loses its effectiveness during operation due to the presence of contaminants. This oil is less subject to biodegradation and does not evaporate but becomes contaminated with substances that are hazardous to human health and the nvironment, so before it can discharged to the environment this oil requires suitable collection and treatment. Therefore to avoid adverse impacts, proper management of waste oil is needed. In this study, waste oil disposal practice in Pakistan has been identified as has the adverse environmental impact associated with it and waste oil management options are discussed in relation to proposed re-cycling options considering the prevailing market price of the new virgin oil. 12 re-generation locations have been identified all over Pakistan to create job opportunities for local people and also reduce transport costs. This study was carried out to evaluate the performance of different methods used to upgrade the waste lube oil into a usable product. Acid/ clay treatment was conducted at laboratory and small pilot scale using the sulfuric acid with different catalysts (Dimethyl Sulfoxide, Dimethyl Formamide and Zeolite) and waste oil ratios. The performance was evaluated against the properties of regenerated oil to the standard base oil, 500N and 150N, and it was found that regenerated oil does not match to standard base oil. In the solvent-extraction process, the performance was evaluated using single and composite solvents with catalysts at laboratory and pilot scale level. The two dependent variables, namely the Percentage of oil loss (POL) and Percentage of Sludge Removal (PSR) were examined as the key parameters in assessing the performance of the extraction process. The solvents used were (70% of 2-propanol and 30% of n-hexane) with addition of KOH, composite solvents (40% 2-propanol, 35% 1-butanol and 25% butanone) and (25% 2-propanol, 37% 1-butanol and 38% butanone) at different solvent-oil ratio and operating variables. In view of the practically and commercial aspect of the project, the used oil recycling process was consecutively run for three or four times at each composition. The physical properties of recovered/re-generated base oil were analyzed and compared. The results from the experimental work shows the laboratory and pilot scale operation revealed similar trends with a little higher performance from the pilot scale operation. This is due to the mechanical mixing of acid-oil/ solvent-oil, coagulants, activated earth clay and controlled heating (dehydration & distillation) extraction of light hydrocarbons and solvents. The properties of re-generated oil were matched to the standard base oil, 500N and 150N, the properties of solvent–oil ratio (25% 2-propanol, 37% Butanol and 38% Butanone) at SOR 6:1 was observed to be the most appropriate solvent composition and achieved about 68% oil recovery and the oil properties compared favorably to graded virgin oil and can be used for similar purposes. Since the quality of regenerated oil matched the virgin oil, it would reduce our dependency on imported oil, save foreign exchange, reduce adverse environment impact and help to preserve oil sources.
مارک، ایڈورڈ ویسٹر ایڈورڈ ویسٹر مارک کا انتقال ایڈورڈ ویسٹر مارک نے جو ایک عرصہ تک لندن یونیورسٹی میں عمرانیات کا پروفیسر تھا، گزشتہ اکتوبر میں انتقال کیا، وہ ایک عمیق النظر فلسفی اور بین الاقوامی شہرت کا مالک تھا، اوائل زندگی میں اس کو خیال پیدا ہوا کہ اخلاقی خیالات اور مذہبی اعتقادات میں گہرا تعلق ہے، چنانچہ اس نقطہ نظر سے اس نے یورپ کے علاوہ دوسری قوموں کے روایات اور اعتقادات کا مطالعہ کرنا چاہا اور اس کے لئے مراکش کو منتخب کیا، اور وہاں جاکر چار سال تک مقیم رہا، یہاں اس نے نہ صرف انسانیاتی معلومات جمع کئے، بلکہ وہاں کے لوگوں طرز زندگی و غور و فکر سے بھی واقفیت حاصل کرکے ان کے رسم و رواج کو آسانی سے سمجھا جو تمدن کے مختلف دور میں پیدا ہوتے رہے، یہاں کی تحقیقات اس نے اپنی مشہور کتاب ’’اخلاقی تخیلات کی ابتدا اور نشوونما‘‘ (The origin and development of moral ideas) میں قلمبند کی جو دو جلدوں میں ۱۹۰۶ء اور ۱۹۰۸ء میں شائع ہوئی تھی، یہ کتاب بہت اہم اور بلند پایہ سمجھی جاتی ہے اور اخلاقیات پر ایک فلسفیانہ مقالہ یا اخلاقی خیالات کی تاریخ کہی جاسکتی ہے، اس کتاب کی خوبی یہ ہے کہ اس میں تحلیلی اور تاریخی تجزیوں میں امتزاج پیدا کرکے یہ دکھایا گیا ہے کہ اخلاقی پسندیدگی اور ناپسندیدگی کی ابتدا معاشرتی تکدر اور تشکر سے ہوتی ہے، ڈاکٹر ویسٹر مارک کی اور دوسری تصنیفات یہ ہیں، مراکش میں انسانی شادی، رسم اور اعتقاد کی تاریخ، (۲)اخلاقی اضافیت، (۳)عیسائی مذہب اور اخلاق۔ (’’ص ۔ ع‘‘، دسمبر ۱۹۳۹ء)
From the very beginning Islam has given great importance to discipline. In every facet of life discipline has a role to play. Today when we delve deep in to our lives, we are amazed as to how it has always proved its worth. It has brought the tide of revolution in everyone's mind. Similarly, the element of discipline saves a society from disruption and instability. It infuses in life satisfaction and contentment. Contrarily, indiscipline and mismanagement give birth to dejection and dissatisfaction. Time management plays a vital role in the establishment of discipline in a society. Considering the vast importance of time management in the light of discipline, the following article throws a great deal of light on it in the Islamic perspective.
Many conventional fluids, such as water, sodium alginate, organic liquids (e.g., propylene and ethylene glycols, etc.) and some others, are quite often used in various engineering and industrial processes as coolants. The use of water in car radiators is a very basic example. Nowadays, scientists are keenly looking for ways to enhance the performance of engines and such equipment where these coolants are being used. Conventionally, the heat transfer capability of these liquids is not up to the mark. Therefore several attempts have been made to enhance their thermo-physical capabilities. The use of nanofluids is one of such efforts. Scientists, over the past few decades, have been working on the idea of mono-nanofluids (nanofluids with single nanomaterials), to enhance the thermal efficiency of these traditional fluids. However, to improve the number of desirable features of mononanofluids, a novel subject of hybrid nanofluids (nanofluids with two or more nanomaterials) has come into existence. It exhibits superior thermo-mechanical properties when compared to mono nanofluids. In this manuscript, a number of thermal conductivity models, for both mono and hybrid nanofluids, have been employed to see the working of these models in different geometries. In the case of hybrid nanofluids, the modified versions of the models (such as Renovated Hamilton and Crosser’s model, Bruggeman’s model, Hamilton and Crosser’s model, Maxwell’s model, and Xue’s model) for thermal conductivity have been considered. The flow of mono as well as hybrid nanofluids inside an expanding\contracting domains, rectangular conduit with the lower stretchable wall, curved stretching surface, and curved channels, have been studied in details. A novel analysis of hybrid nanofluid flow between two Riga plates is also a part of this manuscript. Moreover, the squeezing flow of a hybrid nanofluid inside a rotating rectangular conduit, with lower stretchable walls, has also been investigated. The impact of the externally applied magnetic field, along with the internal heat generation phenomena, on the flows and heat transport mechanism of some mono and hybrid nanofluids have thoroughly been examined. Heat and mass transfer under the influence of nonlinear thermal radiation and chemical reaction effects in several geometries have been studied in this manuscript. xi In our analysis, we have used certain similarity transformations and scaling parameters to reduce the governing partial differential equations to the corresponding systems of nonlinear ordinary differential equations (dimensionless). This process reduces the number of variables, and parameters, which leads to a relatively more straightforward mathematical treatment. However, the resulting systems are still complicated enough to have an exact solution. For their treatment, we have discussed the implementation of several approximation techniques based on the method of weighted residuals and wavelet methods. We have also proposed some modifications in wavelet methods for a better and more flexible implementation. The plots for velocity, together with temperature, and concentration profiles (wherever applicable) are presented to capture the effects of involved parameters on the respective profiles. It has been found that the addition of nanomaterials significantly boosts the thermal and heat transport properties of the host fluid and that these phenomena are more prominent for the hybrid nanofluids.