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Search Results: 1 - 10 of 594270 matches for " N. A. El-Hussiny "
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Production of Iron from Mill Scale Industrial Waste via Hydrogen  [PDF]
N. M. Gaballah, A. F. Zikry, M. G. Khalifa, A. B. Farag, N. A. El-Hussiny, M. E. H. Shalabi
Open Journal of Inorganic Non-metallic Materials (OJINM) , 2013, DOI: 10.4236/ojinm.2013.33005
Abstract:


Mill scale is very attractive industrial waste due to its richness in iron (about = 72% Fe). In this paper, the characterizations of mill scale were studied by different methods of analyses. The produced mill scale briquettes were reduced with hydrogen at varying temperatures, and the reduction kinetics was determined. Two models were applied and the energy of activation was calculated.


Effect of recycling blast furnace flue dust as pellets on the sintering performance
El-Hussiny N.A.,Shalabi M.E.H.
Science of Sintering , 2010, DOI: 10.2298/sos1003269e
Abstract: The Egyptian Iron and Steel Company generates a great amount of blast furnace flue dust. The recovery of metals and carbon from this flue dust becomes a very important demand due to the increase of the price of coke breeze and the decrease of the primary source of metals. At the same time, it make the environment more safe by decreasing pollution. Introducing these dust fines in the sintering process proves to be very harmful for different operating parameters. Thus, this study aims at investigating the production of pellets resulting from these fines, using molasses as organic binder and its application in sintering of iron ore. The sintering experiments were performed using flue dust as pellets as a substitute of coke breeze. The results revealed that, sintering properties such as inter strength increases with using the flue dust pellets, while productivity of both the sinter machine and sinter machine at blast furnace yard decreases. Also the vertical velocity of the sinter machine and the weight loss during the reduction of produced the sinter by hydrogen decrease.
Studying the pelletization of rosseta ilmenite concentrate with coke breeze using molasses and reduction kinetics of produced pellets at 800-1150oC
El-Hussiny N.A.,Shalabi M.E.H.
Science of Sintering , 2012, DOI: 10.2298/sos1201113e
Abstract: Ilmenite ore fine and coke breeze as reduced material which were pelletized with different amounts of molasses were studied in this investigation. The produced pellets at optimum condition were reduced in nitrogen atmosphere at temperature range 800-1150oC to determine the controlling mechanism. The reduction indicated that the reduction rates increased as the temperature increased and the controlling mechanism of reaction rate is solid-solid reaction.
Granulation of coke breeze fine for using in the sintering process
Mohamed F.M.,El-Hussiny N.A.,Shalabi M.E.H.
Science of Sintering , 2010, DOI: 10.2298/sos1002193m
Abstract: Coke breeze is the main fuel used in the sintering process. The value of -3+1 mm. represents the most favorable particle size for coke breeze in the sintering process. About 20% of total coke fines (-0.5 mm) are produced during different steps of preparation. Introducing these fines during the sintering process proves to be very harmful for different operating parameters. Thus ,this study aims at investigating the production of granules resulting from these fines using molasses as organic binder and its application in sintering of an iron ore. The results showed that the granules having the highest mechanical properties were obtained with 14.5 wt % molasses addition. The sintering experiments were performed by using coke breeze in different shapes (-3+1 mm in size, coke breeze without sieving and coke breeze granules -3+1 mm). The reduction experiments, microscopic structure and X-ray analysis for the produced sinter were carried out. The results revealed that, all sinter properties (such as shatter test, productivity of sinter machine and blast furnace, reduction time and chemical composition) for produced sinter by using coke breeze with size -3+1 mm and coke breeze granules were almost the same. The iron ore sinter which was produced by using coke breeze without sieving yielded low productivity for both sinter machine and blast furnace. Furthermore, using coke breeze without sieving in sintering of an iron ore decreases the vertical velocity of sinter machine and increases the reduction time.
Recycling of mill scale in sintering process
El-Hussiny N.A.,Mohamed F.M.,Shalabi M.E.H.
Science of Sintering , 2011, DOI: 10.2298/sos1101021e
Abstract: This investigation deals with the effect of replacing some amount of Baharia high barite iron ore concentrate by mill scale waste which was characterized by high iron oxide content on the parameters of the sintering process., and investigation the effect of different amount of coke breeze added on sintering process parameters when using 5% mill scale waste with 95% iron ore concentrate. The results of this work show that, replacement of iron ore concentrate with mill scale increases the amount of ready made sinter, sinter strength and productivity of the sinter machine and productivity at blast furnace yard. Also, the increase of coke breeze leads to an increase the ready made sinter and productivity of the sintering machine at blast furnace yard. The productivity of the sintering machine after 5% decreased slightly due to the decrease of vertical velocity.
Reducibility study of Rossetta ilmenite ore briquettes and powder with coke breeze at 800-1100°C
Abd el Gawad Hala H.,El-Hussiny N.A.,Wassef Marguerite A.,Khalifa M.G.
Science of Sintering , 2013, DOI: 10.2298/sos1301079a
Abstract: Ilmenite ore fine and coke breeze as reduced material were briquetted with different amounts of organic materials such as molasses or pitch were studied in this investigation. The produced briquettes at reasonable condition were reduced in nitrogen atmosphere at temperature range 800 - 1100oC to determine the factors controlling the reduction and to determine the controlling mechanism. Also ilmenite ore fine with coke breeze were reduced at the same temperature range in nitrogen atmosphere without briquetting process, for the sake of comparison.
Reduction of Low Grade Egyptian Manganese Ore via Hydrogen at 800℃ - 950℃  [PDF]
Hala H. Abd El-Gawad, M. M. Ahmed, N. A. El-Hussiny, M. E. H. Shalabi
Open Access Library Journal (OALib Journal) , 2014, DOI: 10.4236/oalib.1100427
Abstract: Low grade manganese ore fine was briquetted with different amounts of molasses under different pressure was studied in this investigation. In this study, the characterizations of raw materials were studied by different methods of analyses such as X-ray and chemical analyses. The results of briquetting show that as the pressing pressure load increased both the drop damage resistance and crushing strength increased and the optimum amount of molasses added was 2% and the pressing pressure was 216.7745 MPa. The produced briquettes were reduced by different flow rate of hydrogen at different temperatures, and the reduction kinetics was determined. The results indicated that: 1) The reduction rates by hydrogen increased with increasing temperature of the reduction; 2) Increase hydrogen flow rate at constant temperature of reduction leads to increase rate of reduction; 3) The zero order is control step at time 0 - 5 min and from 5 to 20 min the gaseous diffusion in case of cylindrical products and from 20 to 60 min the reaction controlled by nucleation and growth.
Sodium Titanates Formation by Roasting of Pellets or Powder Mixture of Soda Ash and Rossetta Region Ilmenite Ore Concentrate in Air  [PDF]
Inass Ashraf Nafeaa, Amina F. Zekry, Mohamed Gamal Khalifa, Abd El-Fatah B. Farag, Naglaa A. El-Hussiny, Khaled El Hossiny, Mohamed El-Menshawi Hussein Shalabi
Open Journal of Metal (OJMetal) , 2014, DOI: 10.4236/ojmetal.2014.42003
Abstract:
Alkaline metals and hydrogen titanates are of great interest for possible applications. The qualities of soda ash and Rosetta ilmenite ore concentrate pellets were investigated. The kinetic formation of sodium titanate via roasting of soda ash and ilmenite pellets and powder was studied in the temperature range of 800C to 900C.
Leptin, insulin and thyroid hormones in a cohort of Egyptian obese Down syndrome children: a comparative study
Yahia Sohier,EL-farahaty Reham M,El-Hawary Amany K,El-hussiny Mona A
BMC Endocrine Disorders , 2012, DOI: 10.1186/1472-6823-12-22
Abstract: Background Obesity is a major worldwide health problem. It is commonly observed in Down syndrome individuals than in the general population. The reason for increased risk of obesity in DS is unclear. The current study was designed to clarify differences in some obesity- related hormones in a group of prepubertal Down syndrome children. Methods Thirty six Egyptian children with Down syndrome were enrolled in this study, divided according to their body mass index (BMI) into 23 obese and13 non obese. Another group of 43 non Down children were recruited, they were divided according to their BMI into 20 patients having simple obesity and 23 non obese, as control groups. Fasting blood samples were collected for estimation of fasting blood glucose (FBG), insulin, leptin, free thyroxin (FT4), thyroid stimulating hormones (TSH) and creatine kinase (CK). Insulin resistance was assessed by Homeostasis Model Assessment method (HOMA-IR). The ratio of leptin to BMI (LEP/BMI) was used as an index of leptin resistance. Results Median values of FBG, insulin, and HOMA-IR were significantly higher in Down versus non Down groups, while median values of leptin and leptin resistance were non-significantly different among Down versus non Down groups. Median TSH values were non- significantly different between obese Down and obese non Down. Although the median values of TSH and FT4 were within normal range in Down groups, four cases of subclinical hypothyroidism were encountered. Leptin levels were correlated with insulin and IR but not with TSH in Down groups. Conclusion Increased circulating leptin, a marker of leptin resistance in obese children with Down syndrome seems to be similar to that in children with simple obesity. Elevated FBG and insulin in obese Down children highlights the presence of early IR. Associated myopathy evidenced by mildly elevated CK levels could be an added factor for obesity in such group of patients.
An Innovative Cloning Platform Enables Large-Scale Production and Maturation of an Oxygen-Tolerant [NiFe]-Hydrogenase from Cupriavidus necator in Escherichia coli
Johannes Schiffels, Olaf Pinkenburg, Maximilian Schelden, El-Hussiny A. A. Aboulnaga, Marcus E. M. Baumann, Thorsten Selmer
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0068812
Abstract: Expression of multiple heterologous genes in a dedicated host is a prerequisite for approaches in synthetic biology, spanning from the production of recombinant multiprotein complexes to the transfer of tailor-made metabolic pathways. Such attempts are often exacerbated, due in most cases to a lack of proper directional, robust and readily accessible genetic tools. Here, we introduce an innovative system for cloning and expression of multiple genes in Escherichia coli BL21 (DE3). Using the novel methodology, genes are equipped with individual promoters and terminators and subsequently assembled. The resulting multiple gene cassettes may either be placed in one vector or alternatively distributed among a set of compatible plasmids. We demonstrate the effectiveness of the developed tool by production and maturation of the NAD+reducing soluble [NiFe]-hydrogenase (SH) from Cupriavidus necator H16 (formerly Ralstonia eutropha H16) in E. coli BL21Star? (DE3). The SH (encoded in hoxFUYHI) was successfully matured by co-expression of a dedicated set of auxiliary genes, comprising seven hyp genes (hypC1D1E1A2B2F2X) along with hoxW, which encodes a specific endopeptidase. Deletion of genes involved in SH maturation reduced maturation efficiency substantially. Further addition of hoxN1, encoding a high-affinity nickel permease from C. necator, considerably increased maturation efficiency in E. coli. Carefully balanced growth conditions enabled hydrogenase production at high cell-densities, scoring mg·(Liter culture)?1 yields of purified functional SH. Specific activities of up to 7.2±1.15 U·mg?1 were obtained in cell-free extracts, which is in the range of the highest activities ever determined in C. necator extracts. The recombinant enzyme was isolated in equal purity and stability as previously achieved with the native form, yielding ultrapure preparations with anaerobic specific activities of up to 230 U·mg?1. Owing to the combinatorial power exhibited by the presented cloning platform, the system might represent an important step towards new routes in synthetic biology.
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