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

Isolation and identification of pathogenic bacteria from ready-to -eat fast foods in Al-Quwayiyah, Kingdom of Saudi Arabia

Food-borne pathogens are becoming a globally formidable health problem and perceived as a major health concern in the Kingdom of Saudi Arabia (KSA). Contamination ensued through unclean raw food materials and particles, use of polluted water, unhygienic preparation processes and use of contaminated containers. Herein, the prevalence of food-borne pathogens in ready-to-eat (RTE) fast foods from fifteen different food eateries such as 7 restaurants, 6 cafeterias and 2 two college canteens in Al-Quwayiyah, Riyadh Region of Saudi Arabia was studied. Microbiological analysis of 155 fast food samples which included, Vegetable salad, Falafel, Kibtha and Shawarma. The isolates were detected using biochemical tests and API 20E and slide agglutination test were conducted for Salmonella spp. detection. Bacterial growth was found in all food samples tested. Moreover, the test also showed high levels of total aerobic count: vegetable salad 6.34+0.03, falafel 5.79 + 0.18, kibtha 5.06 +0.02 and shawarma 3.54 + 0.13. Organisms isolated include Salmonella spp. (15%), Escherichia coli (18%) and Staphylococcus aureus (7%). Salmonella is one of the most virulent pathogen implicated in food-borne disease outbreaks. There are numerous transmission routes for Salmonellosis, but the majority of the human infections are derived from consumption of contaminated poultry products. Consistently, Salmonella Enteritidis, Salmonella Typhimurium and Salmonella Heidelberg are the three most frequent serotypes recovered from humans each year. Serologically identified Salmonella serotypes from RTE fast food samples were Salmonella Typhimurium with 65%, the most predominant one compared to Salmonella Enteritidis that was 35%. The bacterial count of vegetable salad, falahfel, kibtha was statistically significant when compared with Shawarma (p < 0.05). This result indicated that most of the ready-to-eat food samples examined in the study did not meet any bacteriological quality standard as recommended by The New South Wales (NSW) Food Authority to be <5.0 log10 CFU g−1 and, therefore, it poses potential risks to consumers. Ready- to- eat fast foods must be cooked and served to the consumers with all hygienic measures.Keywords: foodborne pathogen, microbial quality, Ready- to- eat fast foods, Al-QuwayiyahAfr. J. Food Agric. Nutr. Dev. 2019; 19(3): 14739-1475

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

INFLUENCE OF FORMULATION FACTORS ON THE SIZE OF NANOSTRUCTURED LIPID CARRIERS AND NANOEMULSIONS PREPARED BY HIGH SHEAR HOMOGENIZATION

Objective: The main purpose of this work was to elucidate the effect of certain formulation factors on the size of nanostructured lipid carriers (NLCs) and nanoemulsions (NEs) by using high shear homogenization method.Methods: NLCs and NEs were prepared by high shear homogenization method using different liquid lipids types such as (Dermarol DCO® and Dermarol CCT®) at different concentrations. The effect of different concentration ratios of Tween 80 to Span 20 (2.5/1, 5/1, 10/1, 15/1) w/w % and different homogenization speeds (12 000, 18 000 rpm) on the resulted particle size were also studied.Results: The results revealed that the optimum NLCs and NEs resulted when we use Dermarol CCT® with a concentration of 90 % as liquid lipid and decreasing surfactant ratio to (2.5/1) w/w % with increasing the homogenization speed to 18 000 rpm. Conclusion: NLCs and NEs were successfully prepared, and from this study, it can be concluded that NLCs have the optimum particle size than Nanoemulsions

Thermal and Mechanical Properties of Polyethylene/Doped-TiO 2

Ethylene polymerization was carried out using highly active metallocene catalysts (Cp2ZrCl2 and Cp2TiCl2) in combination with methylaluminoxane. Titanium (IV) oxide containing 1% Mn as dopant was used as nanofillers. The effects of filler concentration, reaction temperature, and pressure on the thermal and mechanical properties of polymer were analyzed. The improvement of nanoparticles dispersion in the polyethylene matrix was checked by WAXD. The thermal properties were analyzed using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The filler impact on the melting temperature of polyethylene synthesized using Cp2ZrCl2 was very minimal which is due to the degree of short-chain branching. The ash content was also analyzed for each nanocomposite and found to be in line with the activity of the catalyst. There was a significant increase in the mechanical properties of the polyethylene by addition of filler

A new squat lobster of the genus Munidopsis (Crustacea, Decapoda, Munidopsidae) from the Mediterranean Sea

8 páginas, 4 figuras[EN]A new species of Munidopsis Whiteaves, 1874 is reported from the south of Crete, at 2046-2104 m, in the eastern Mediterranean Sea. The species (M. ariadne) is morphologically closely related to M. maunga Schnabel and Bruce, 2006, from New Zealand. The species is also close to M. polymorpha Koelbel, 1892, from Lanzarote, Canary Islands, and M. talismani A. Milne Edwards and Bouvier, 1894, from the NW Africa. The new species is described and illustrated and a diagnosis along with full illustration is provided for the latter 2 species.[ES]Una nueva especie de crustáceo del género Munidopsis (Crustacea: Decapoda: Munidopsidae) del mar Mediterráneo. – Se describe una especie nueva de Munidopsis Whiteaves, 1874 capturada al sur de Creta, a 2046-2104 m, en el Mediterráneo oriental. La especie (M. ariadne) es próxima morfológicamente a M. maunga Schnabel and Bruce, 2006, de Nueva Zelanda. La especie está también relacionada con M. polymorpha Koelbel, 1892, de Lanzarote, Islas Canarias, y M. talismani A. Milne Edwards and Bouvier, 1894, del NO de África.Peer reviewe

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

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

Differential, Tissue-specific, Transcriptional Regulation of Apolipoprotein B Secretion by Transforming Growth Factor β

n/