Arabic Imperfect Verbs in Translation: A Corpus Study of English Renderings

This paper proposes a model for translating Standard Arabic imperfect verbs into English based on their contextual references. It starts with a brief introduction to tense and aspect in English and Arabic. Then, it shows the study aim and technique. After that, it provides an analysis of the study results by discussing the various translations of Arabic imperfect verbs in the translations of two novels written by Naguib Mahfouz. The study compares the translations with the original texts to highlight the different English renderings of the Arabic imperfect verbs.Cet article propose pour traduire en anglais des verbes arabes standard à l’inaccompli un modèle basé sur les références contextuelles. Il commence par une brève introduction sur le temps et l’aspect en anglais et en arabe. Ensuite, il présente le but et la technique d’étude. Il fournit une analyse des résultats d’étude en s’appuyant sur les diverses traductions des verbes arabes à l’inaccompli dans les traductions de deux romans de Naguib Mahfouz. L’étude compare les traductions aux textes originaux pour accentuer les différents réalisations en anglais de ces verbes arabes

A comparative structural characterisation of different lignin biomass

This study focuses on the structural characterisation techniques of lignin, which is the most abundant component in biomass and commonly produced as residual product in pulp mills industry. It is inexpensive, non-toxic and biodegradable. Four different lignins have been selected for this study including Alcell lignin, Kraft lignin and two milled wood lignins (MWL) derived from coniferous trees (softwoods) and deciduous trees (hardwood). Fourier transform infrared (FTIR) spectroscopy analysis has been performed on all four types of lignin to identify the functional groups present in the lignin structure. The results have indicated that Alcell lignin consists of more desirable functional groups than Kraft lignin with higher phenolic, carbonyl and aromatic groups. Elemental analysis has been performed to examine the carbon and hydrogen content. The elemental analysis results indicates that MWL contain more hydrogen and carbon in comparison to other two commercial lignins. Heating values have been investigated in terms of higher heating value (HHV) and lower heating value (LHV). The lowest values of HHV and LHV have been reported for Kraft lignin due to its condensed structure. The differential thermogravimetry (DTG) analysis have been performed, which determines the maximum degradation temperature of the lignins. The start and maximum degradation temperature for each lignin help to set the pyrolysis temperature of the lignin for bio-oil production. Components that have been observed via Py-GC-MS analysis have indicated that degradation of bonds has led to the formation of three main structural units of lignin known as guaiacyl (G), syringyl (S) and p-hydroxyphenyl propane (p-H)–type. The results indicate that the Py-GC-MS analysis of MWL have higher aromatic components in comparison to the commercially available lignins

A Conceptual Efficient Design Of Energy Recovery Systems Using A New Energy-area Key Parameter

Energy integration in petrochemical and refining industries is an effective concept to minimize dependence on heating and cooling utilities through networks of exchanger equipment. Pinch Analysis is very popular and successful technique to optimize heat recovery between heat sources and sinks. Yet, design of networks of exchangers is challenging and requires careful attention to energy consumption and exchanger areas. This work presents a graphical methodology to design exchanger networks taking into account both heat loads and transfer areas of exchanger units in one single information. A new parameter is introduced for design that is the ratio between the heat load and the exchanger area and is determined in kW/m2. It is defined as an energy-area parameter expressing how much heat the exchanger would transfer per every meter square of area. Such parameter will be valuable key in design to screen matches of exchangers providing that both the heat and area are considered. The higher the value of the parameter, the better the performance of the exchanger, i.e. maximum heat transfer rate for minimum exchanger area. The design methodology embedding the energy-area parameter guarantees HEN designs with energy targets and minimum areas. A case is studied for the production of 100,000 t/y of dimethyl ether. An optimum network is generated by applying the new parameter with less exchanger areas and hot utility of 25% and 30%, respectively compared with an automated design by Aspen Energy Analyzer®. Also, substantial savings of about 47% in the total cost of the network are earned

Simulation And Optimization Of Waste Heat To Electricity Through Organic Rankine Cycles (ORCs): A Case Study In An Oil Refinery

Energy efficiency has become a global problem that is detrimental to the chemical industries technically, economically and to the environment. Organic Rankine Cycle (ORC) is a promising technology that can solve this problem by recovering heat from low-grade waste heat sources by using organic working fluids. The heat source for the ORC system used in this article is air leaving air coolers in an oil refinery with a temperature of 140o C. The heat exchanger data for this refinery was used in the simulation of a basic cycle and a regenerative cycle using ASPEN HYSYS V.10. These ORC systems were simulated using hydrocarbons, refrigerants, and alternative refrigerants as the working fluids to compare their performance at three different condensation temperatures which are 15o C, 35o C, and 50o C. The system was optimized using the HYSYS optimizer to reach the optimum conditions for each working fluid. Results of this study have proven that the alternative working fluids R1234ze (Z) and R1224yd (Z) perform very well when compared to hydrocarbon working fluids and outperform the regular refrigerants. For the basic cycle which yielded the optimum results, R1234ze (Z) produced 1258.90 kW of turbine work and has a thermal efficiency of 11.31%. Hence, they are promising working fluids and are highly recommended to be used in the future since they perform highly economically in addition to being environmentally friendly

Mathematica as an Efficient Tool to Optimize the Kinetic Study of Ethyl Acetate Hydrolysis

Mathematica is a powerful program for computing both numeric and algebraic calculations as well as graphing two- and three-dimensional curves and surfaces. It is used increasingly in many fields of science now such as physics, engineering, chemistry and even biology because of the fast interaction of mathematics with almost the fields of science nowadays. We report here, optimizing the kinetic data for the hydrolysis of ethyl acetate through caustic soda via using Mathematica

Hydrothermal Synthesis Of Graphene Supported Pd/Fe 3 O 4 Nanoparticles As Efficient Magnetic Catalysts For Suzuki Cross – Coupling

This research reports a reproducible, reliable, and efficient method for preparing palladium nanoparticles dispersed on a composite of Fe3O4 and graphene as an active catalyst with high efficiency for being used in Suzuki cross – coupling reactions. Graphene supported Pd/Fe3O4 nanoparticles (Pd/Fe3O4 /G) exhibit a remarkable catalytic performance towards Suzuki coupling reactions. Moreover, the prepared catalyst recyclability was up to nine times without losing its high catalytic activity. The catalyst was prepared using hydrothermal synthesis; the prepared catalyst is magnetic in order to facilitate catalyst separation out of the reaction medium after reaction completion simply through using a strong magnet. This approach offers unique advantages including recyclability, mild reaction conditions, and reproducibility. Furthermore, the magnetic properties of the prepared catalyst made a huge enhancement to the ability to purify the reaction products from catalyst and other side products. The high catalytic performance and recyclability of the prepared catalyst are due to the strong interaction between the catalyst and the support. Moreover, the reduced GO nanosheets have defect sites acting as nucleation centers to anchor the Pd and Fe3O4 nanoparticles and hence minimize the harmful effect of potential agglomeration and subsequently the anticipated decrease in the catalyst catalytic activity as a direct impact for this unfavorable agglomeration

The Kinetic Study of DPT Using Mathematica as an Efficient Optimization Tool

Mathematica is a powerful program for computing both numeric and algebraic calculations as well as graphing two- and three-dimensional curves and surfaces. It is used increasingly in many fields of science now such as physics, engineering, chemistry and even biology because of the fast interaction of mathematics with almost the fields of science nowadays. Synthesis of Cyclotetramethylene Tetramine through the action of nitrating mixture formed of ammonium nitrate and fuming nitric acid on hexamine in presence of acetic acid, acetic anhydride and p-formaldehyde has been proven. The pathway is relatively long and Hexamine Dinitrate and Dinitro Pentamethylene Tetramine (DPT) are two of the main intermediate compounds. The former was prepared, purified, and then characterized. Conversion of this compound into the latter has been followed up experimentally. Herein, we report the Preparation of Dinitro Pentamethylene Tetramine (DPT) from Hexamine Dinitrate - as an alternative synthetic route - which is an important intermediate appears through preparation of DPT from Hexamine directly. DPT was prepared at different temperatures. The variation of some factors like: temperature and time has been investigated. The obtained results were reliable and consistent with the literature. The conversion of Hexamine Dinitrate to HMX as another synthetic route was not fully studied from the point of view of kinetics. In this paper, it is intended to study the effect of time and temperature on the conversion rate of hexamine dinitrate to DPT. This scientific approach is considered as a bridge through which we aim to initiate a complete kinetic study of an important intermediate in the synthesis route of one of the most powerful energetic materials. We report here, optimizing the kinetic data for the synthesis of DPT via using Mathematica

Experimental islet transplantation

Pancreatic islet transplantation is a promising treatment modality for patients with insulin- dependent diabetes. Besides whole pancreas transplantation, it is the only treatment that can make patients normoglycemic without risking episodes of hypoglycemia. It can also prevent, slow down and even reverse the development of secondary complications to diabetes. Compared to whole pancreas transplantation, islet transplantation is much less invasive and may also be used in patients with a high surgical risk profile, but clinical outcome data are so far better for whole pancreas transplantation. However, graft survival necessitates life-long immunosuppression and for islet transplantation more than one donor is usually needed. There is therefore a need for more specific immunosuppression with less side effects as well as methods by which the donor pool can be expanded. In this project we have assessed the capability of costimulation blockade, i.e. blocking the second signal of T lymphocyte activation, to prevent rejection of allogeneic (between individuals) and xenogeneic (between species) islet grafts, in particular when transplanted to recipients already sensitized to the graft. We have shown that a triple costimulation blockade regimen with anti-CD154 antibodies, CTLA4Ig and anti-LFA-1 antibodies could not prolong survival of islet allografts when transplanted under the kidney capsule of sensitized C57BL/6 mice. Either induced antibodies or memory T cells may be responsible for this inability of conventional costimulation blockade to prolong graft survival in sensitized animals. We tried to resolve this question in a rat-to-mouse xenotransplantation model, in which immune or naïve serum was injected intraperitoneal at the time of islet transplantation. Again, the recipient animals were given costimulation blockade. The immune serum had no negative impact on the grafts immediately (within 96 hours) post- transplantation or on the graft survival long-term in mice receiving costimulation blockade. These results suggest that preformed antibodies are not the main cause for graft rejection in sensitized recipients treated by costimulation blockade. In the animal transplantation models used, streptozotocin or alloxan is used to induce diabetes through their toxic effects on pancreatic β-cells. It has been reported that these drugs are also toxic for other cells and tissues, including cells of the immune system. Therefore, we compared recipients given streptozotocin or alloxan for diabetes induction with regard to graft survival times, spleen size and toxic effects on leukemic cells in vitro. We conclude that streptozotocin is more toxic on immune cells than alloxan, and may therefore not be a suitable agent for diabetes induction in transplantation models assessing different immunosuppressive protocols. Further, we showed that the erythropoietin analogue, pyroglutamate helix B surface peptide (ARA 290) could protect islets from apoptosis when exposed to pro-inflammatory cytokines in vitro, while no clear effect was seen on graft survival when injected into the recipients. Further studies are needed on this potential islet-protective agent. In conclusion, islet transplantation holds great promise for the future as a treatment modality for insulin-dependent diabetes. However, further research is needed in order to find optimal immunosuppressive protocols with acceptable side effects that can promote long term graft survival. Costimulation blockade may be such a modality provided memory T cell activation can be perturbed and tolerance induced also in sensitized recipients

Better Heat And Power Integration Of An Existing Gas-oil Plant In Egypt Through Revamping The Design And Organic Rankine Cycle

Objective: The current study aims mainly to Maximize Condensate Recovery (NGLs), focusing on a gas processing train of Gas-Oil Separation Plant (GOSP) located in Egypt with a capacity of 4,230 kmole/h. Methods: The research study accounts for the constraint of Reid Vapor Pressure (RVP) specification, which makes the storage in floating roof tanks is of a great risk. The study proposes the installation of the cryogenic train that recovers condensates (C4+). This train comprises of compression unit, expansion unit, three-phase separators and a re-boiled absorber. The problem of RVP will no longer exist because of the re-boiled absorber achieving RVP according to export specifications (RVP below 82.74 kPa). Heat integration is applied over the whole process to minimize the reliability of the external utilities. Further, an Organic Rankine cycle (ORC) is introduced to the existing unit for more heat integration to develop useful work from process waste heat. Furthermore, both environmental emissions of CO2 and economic implications are investigated. Results: Energy integration played a vital role in decreasing the compressing power by about 31%, the cooling load by about 81%, and eliminating the heating load leading to zero CO2 emissions. Conclusion: The new energy-integrated retrofit scenarios exceed the recommended revamping schemes by previous works and base case in all aspects of condensate recovery, energy-saving, environmental concerning and economics

Graphical Revamping Of A Crude Distillation Unit Under Two Variable Operational Scenarios - Naphtha Stabilizer And Reformer Operated

Energy costs represent significant parts of the total operating costs of crude refining industries. Energy integration is a typical solution to reduce heating and cooling utilities in crude refining plants through maximizing the target temperature of crude oil streams before entering the furnace. Over the past few decades, a significant progress has been made in energy integration methods including Pinch technology and mathematical programming approaches. Example of these is a graphical technique which plots Thot versus Tcold for energy analysis and revamping studies. The current research employs the Thot - Tcold diagrams in an algorithm to retrofit an existing crude atmospheric distillation unit (CDU) located in north of Egypt (Suez region). This real CDU unit is operated under two different operational modes: (i) without naphtha stabilizer; the process reformer is in operation to reform all naphtha streams without stabilization, and (ii) with naphtha stabilizer; LPG is separated from naphtha stream. The performance of the current HEN is analyzed using the graphical axes of Thot - Tcold diagrams. The graphical method is used to identify exchangers across the Pinch and recognize the potential modifications to improve the energy performance and reduce fuel consumption. Implementing the graphical identified modifications on the existing plant resulted in: (1) stabilizer scenario; energy savings are achieved by 21.1% with additional capital investment of 0.81 MM$and annual energy savings of 0.82 M$, (2) reformer scenario; the energy savings are 0.42 MM$with capital investment of 0.33 M$