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Ore Controls and Metallogenesis of Au-Ag Deposits at Atalla Mine,Central Eastern Desert of Egypt

Acta Geologica Sinica(English Edition) 2020年第5期94卷 1451-1470页

作者： mohamed ABD el MONSEF Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Institute of Geological Sciences Faculty of ScienceMasaryk UniversityBrnoCzech Republic

Gold-silver deposits in the Atalla area occur as hydrothermal quartz veins in NE–SW pre-existing fractures within the Atalla granitic *** orientation of such quartz veins has been attributed to extensional behavior related to the Atalla Shear Zone(ASZ).The Atalla area is covered by a variety of lithologies that are(from oldest to youngest):metasedimentary rocks,metavolcanic rocks,ophiolite assemblage(serpentinites/talc-carbonates),Atalla granite and Dokhan volcanic ***,Atalla granite ranges in composition from granodiorite to *** geochemistry constrains the calc-alkaine affinity of the Atalla granite that was intruded within an orogenic(syncollision)tectonic *** ore minerals are represented by gold/silver(electrum),pyrite(Py1&Py2),arsenopyrite,pyrrhotite,sphalerite,chalcopyrite,galena,covellite and *** temperature of ore formation ranges from 240 to 285℃and the estimated fluid pressure is in the range of 20–100 *** on the geological setting,ore textures and fluid characteristics;the Atalla Au-Ag deposits are considered to be orogenic in nature,formed from a continental collision(~653-590 Ma),synchronous with the emplacement of calc-alkaline magmatism during the evolutionary history of the Arabian Nubian Shield(ANS).The initial ore-forming fluid was primarily derived from a metamorphic source related to ophiolitic-serpentinite rocks under deep regional conditions of greenschist-amphibolite facies,where the Atalla granitic eruption provided the required temperature conditions for the metamorphic process to take *** such conditions,the transportation of ore metals as bisulfide complexes is *** deposition of ore minerals was triggered by fluidwallrock interaction through fracture pathways in conjunction with a temperature-pressure drop that is likely to have been related to uplift into the crustal levels.

关键词： Gold-silver arsenopyrite geothermometry fluid inclusions orogenic deposits Atalla Shear Zone(ASZ)

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Epidemiologic Profile Urinary Tract Infections: Experience of the Microbiology Laboratory of the University Hospital mohamed VI in Tangier

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Advances in Infectious Diseases 2024年第3期14卷 620-627页

作者： Nouhaila Chahid Chaimae Errabhi el Ghali Tazi Sihame el jamii Yasmine Kemmach Karima Rissoul Department of Microbiology University Hospital Center of Tangier Tangier Morocco Department of Medicine and Pharmacy University of Abdelmalek Essaadi Tangier Morocco

Urinary tract infection is one of the most common bacterial infections in humans. The urine cytobacteriological examination is the key test for its diagnosis. This work aims to Evaluate the prevalence of urinary tract infection at the Microbiology Laboratory of the University Hospital mohamed VI in Tangier and to highlight its epidemiological and bacteriological characteristics. It was a descriptive study with retrospective data collection which took place from January 2021 to June 2022, at the Microbiology Laboratory of the university hospital mohamed VI in Tangier. It covered all urine cytobacteriological examinations (ECBU) during the study period. We identified 77 cases of urinary tract infections out of 300 requests for (ECBU), that is a positivity rate of 25 %. The mean age was 55 years. The male gender was predominant. The epidemiological profile of the isolated strains was dominated by Enterobacteriaceae 81 %, followed by Gram-positive cocci 11 % and non-fermenting gram-negative bacteria 8 %. The main bacteria responsible for urinary tract infections in order of frequency: Escherichia coli 42 %, Klebsiella pneumoniae 20 %, Enterobacter cloacae 9 %, Staphylococcus aureus 6 %, Pseudomonas aeruginosa 5 % and Acinetobacter baumannii 3%. Most of the analyzed organisms showed resistance, especially to the beta-lactam antibiotic;the enterobacteria strains isolated had revealed resistance to amoxicillin: 74%, to amoxicillin-clavulanic acid in 40% of cases, and to third-generation cephalosporins in 24%. In terms of resistance mechanisms, 11 % of the Enterobacteriaceae were extended-spectrum β-lactamase producers and 9 % of the specimens were identified as carbapenemase producers. Of the Staphylococcus aureus strains isolated, 75% were resistant to meticillin. The Glycopeptides and linezolid were the most active molecules on these isolated strains. 15% of Enterococcus species isolated in our laboratory were resistant to glycopeptides (vancomycin and teicoplanin).

关键词： Epidemiology Urinary Tract Infection Cytobacteriological Urinary Test Uropathogens Multiresistant Bacteria Antibiotic Sensitivity Morocco

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Heterogeneous performance analysis of the new model of CFAR detectors for partially-correlated χ~2-targets

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Journal of Systems Engineering and electronics 2018年第1期29卷 1-17页

作者： el_MASHADE mohamed Bakry electrical Engineering Department Faculty of Engineering Al Azhar University

To mitigate the deleterious effects of clutter and jammer, modern radars have adopted adaptive processing techniques such as constant false alarm rate(CFAR) detectors which are widely used to prevent clutter and noise interference from saturating the radar’s display and preventing targets from being *** paper concerns with the detection analysis of the novel version of CFAR schemes(cell-averaging generalized trimmed-mean,CATM) in the presence of additional outlying targets other than the target under research. The spurious targets as well as the tested one are assumed to be fluctuating in accordance with the χ~2-model with two-degrees of freedom. In this situation, the processor performance is enclosed by the swerling models(SWI and SWII). Between these bounds, there is an important class of target fluctuation which is known as moderately fluctuating targets. The detection of this class has many practical applications. Structure of the CATM detector is described briefly. Detection performances for optimal, CAM, CA, trimmed-mean(TM) and ordered-statistic(OS) CFAR strategies have been analyzed and compared for desired probability of false alarm and determined size of the reference window. False alarm rate performance of these processors has been evaluated for different strengths of interfering signal and the effect of correlation among the target returns on the detection and false alarm performances has also been studied. Our numerical results show that, with a proper choice of trimming parameters,the novel model CAM presents an ideal detection performance outweighing that of the Neyman-Pearson detector on condition that the tested target obeys the SWII model in its fluctuation. Although the new models CAS and CAM can be treated as special cases of the CATM algorithm, their multi-target performance is modest even it has an enhancement relative to that of the classical CAcheme. Additionally, they fail to maintain the false alarm rate constant when the operati

关键词： adaptive target detection multi-pulse performance noise and interference partially-correlated χ~2-targets SWI & SWII target fluctuation models target multiplicity environments

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Innovative surfactant of Gemini-type for dissolution mitigation of steel in pickling HCl medium

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Chinese Journal of Chemical Engineering 2021年第6期34卷 125-133页

作者： Medhat Kamel mohamed Hegazy Salah Rashwan mohamed el Kotb Department of Chemistry Faculty of ScienceSuez Canal UniversityIsmailia 41522Egypt Egyptian Petroleum Research Institute(EPRI) Nasr CityCairo 11727Egypt

A new surfactant of Gemini-type,N,N'-((phthylbis(oxy))bis(ethane-2,1-diyl))bis(N,N-dimethyldodecan-1-aminium bromide)is prepped&*** dissolution suppression impact of the new compound on steel is performed in 1 mol·L^(-1)HCl environment by means of chemical and electrochemical *** prepared surfactant is an agreeable dissolution inhibitor for *** mitigation efficacy rises with the quantity of the *** surfactant belongs to inhibitors of *** adsorption of the synthesized compound followed the Langmuir's *** negative magnitudes of bothΔG_(ads)^(θ) andΔH^(adsθ)indicate that the adsorption process proceeds from its own accord and *** mechanism of adsorption is elucidated by scanning *** is established that the transfer resistance(R_(ct))value rose,where the value of the phase element(CPE)reduced with the amount of synthesized *** to the experimental data arrived by surface tension measurements,the prepared compound is a powerful active agent at the air/water boundary.

关键词： Innovative Gemini surfactant Synthesis Dissolution mitigation Steel Pickling HCl media

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Effect of different metal sulfate precursors on structural and catalytic performance of zirconia in dehydration of methanol to dimethyl ether

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燃料化学学报 2018年第1期46卷 67-74页

作者： Abd el-Aziz A.Said mohamed Abd el-Aal Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt

ZrO_2 was treated with 10% SO_4^(2-) from different metal sulfate precursors for methanol dehydration to dimethyl *** the samples exhibited tetragonal phase and no diffraction peaks corresponding to metal sulfates or metal oxides were *** FT-IR results revealed that there were different interactions between sulfate and ZrO_2,and this had a great effect on the surface area of the *** catalytic activity was measured over the catalysts in the temperature range of 100-300 ℃.The results revealed that sulfated zirconia with CuSO_4·5 H_2O and Al_2(SO_4)_3·16 H_2O showed the best catalytic *** maximum yield of DME ≈87% was obtained over CuSZ at a reaction temperature of 275 ℃.Moreover,the catalytic activity of the catalysts was correlated well with their surface acidity that measured by dehydration of isopropanol.

关键词： MSO 4/ZrO2 甲醇脱水 DME

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In field control of Botrytis cinerea by synergistic action of a fungicide and organic sanitizer

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Journal of Integrative Agriculture 2018年第6期17卷 1401-1408页

作者： Fatima Ayoub Najwa Ben oujji mohamed Ayoub Athman hafidi Rachid Salghi Shehdeh Jodeh Laboratory of Applied Chemistry and Environment National School of Applied ScienceIbn Zohr University Ecolink International Zone Industrielle Department of Chemistry An-Najah National University

A new Integrated Pest Management program based on the combination of synthetic pesticide with a GRAS （generally recognized as safe）-classified sanitizer for the control of Botrytis cinerea in field conditions was described. The aim behind this research was to determine whether the use of this mixture would enhance the efficiency of pesticides while decreasing the recommended dose. Naturally infected tomato plants, grown in the greenhouse, were treated with two commonly used fungicides SWITCH （Syngenta, Switzerland） and SIGNUM （BASF, Germany） each alone or combined with a commercially available organic sanitizer PERACLEAN？5 （Evonik Industries, Germany）. A total of 27 treatments were tested consisting of three concentrations of synthetic fungicide （×1, ×1/2 and ×1/4 of the recommended dose） either applied separately or combined with three concentrations of the tested sanitizer （0.5, 1 and 1.5％）. The control efficacy achieved by the fungicides applied alone ranged between 0 and 66.7％ while all fungicide-sanitizer mixtures resulted in up to 70％ control of grey mould. The treatment that provides the maximum control of B. cinerea was the result mixture of ×1/4 of the recommended concentration of SWITCH （15 g L-1） with 0.5％ of PERACLEAN？5. This combination suppressed 85％ of grey mold infections while decreasing the usually used amount of this pesticide by 75％, reducing therefore the well known negative impacts of chemical pesticides on environment and consumers health.

关键词： Botrytis cinerea tomatoes peroxyacetic acid PERACLEAN^(■)5 SIGNUM SWITCH

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Strong Band-Edge Emission from ZnS Quantum Dots Stabilized by Gum Arabic

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Chinese Physics Letters 2008年第12期25卷 4480-4481页

作者： Hatim mohamed el-Khair Dirar Department of Physics Faculty of Science and Technology Ai-Neelain University PO Pox 12702 Khartoum 11121 Sudan

ZnS quantum dots （QDs）, prepared by soft-condensation, exhibit robust structure of a quantum size equal 3.13 nm mediated two-dimensional gum Arabic surfactant as characterized by scan tunnelling microscope （STM）. Strong blue-shifted absorption and emission bands are depicted by optical characterization even for the sample stored under ambient condition for two weeks. These enhancements can be attributed to the completely passivated surface trap states by Gum Arabic.

关键词： field emission molybdenum dioxide enhancement factor

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Advanced algorithms for retrieving pileup peaks of digital alpha spectroscopy using antlions and particle swarm optimizations

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Nuclear Science and Techniques 2020年第4期31卷 47-68页

作者： mohamed S.el_Tokhy Engineering Department NRCAtomic Energy AuthorityP.No.13759InshasEgypt

Optimization algorithms are applied to resolve the second-order pileup(SOP)issue from high counting rates occurring in digital alpha *** are antlion optimizer(ALO)and particle swarm optimization(PSO)*** optimization algorithms are coupled to one of the three proposed peak finder *** custom time-domain algorithms are proposed for retrieving SOP peaks,namely peak seek,slope tangent,and fast array *** addition,an average combinational algorithm is *** time occurrence of the retrieved peaks is tested for an elimination of illusive *** methods are inaccurate and *** and PSO optimizations are used for the localization of retrieved *** cost values that achieve the best fitness values are ***,the optimum positions of the detected peak heights are *** metrics of the optimized algorithms and their influences on the retrieved peaks parameters are *** among such algorithms are investigated,and the algorithms are inspected in terms of their computational time and average *** peak seek algorithm achieves the lowest average computational error for pulse parameters(amplitude and position).However,the fast array algorithm introduces the largest average error for pulse *** addition,the peak seek algorithm coupled with an ALO or PSO algorithm is observed to realize a better performance in terms of the optimum cost and computational *** contrast,the performance of the peak seek recovery algorithm is improved using the ***,the computational time of the peak optimization using the PSO is much better than that of the ALO *** a final conclusion,the accuracy of the peaks detected by the PSO surpasses that for the peaks detected by the *** implemented peak retrieval algorithms are validated through a comparison with experimental results from previous *** proposed algorithms achieve a notable pr

关键词： Alpha spectrometry instrument Second-order pileup Signal processing Optimization algorithms

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Predictors of long-term survival after pancreaticoduodenectomy for peri-ampullary adenocarcinoma: A retrospective study of 5-year survivors

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Hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 443-449页

作者： Ayman el Nakeeb mohamed el Sorogy Helmy Ezzat Rami Said mohamed el Dosoky mohamed Abd el Gawad Ahmed M elsabagh Ehab el Hanafy Gastroenterology Surgical Center Mansoura University

Background: Pancreaticoduodenectomy(PD) is the standard curative treatment for periampullary tumors. The aim of this study is to report the incidence and predictors of long-term survival( ≥ 5 years) after PD. Methods: This study included patients who underwent PD for pathologically proven periampullary adenocarcinomas. Patients were divided into 2 groups: group(I) patients who survived less than 5 years and group(II) patients who survived ≥ 5 years. Results: There were 47(20.6%) long-term survivors( ≥ 5 years) among 228 patients underwent PD for periampullary adenocarcinoma. Patients with ampullary adenocarcinoma represented 31(66.0%) of the long-term survivors. Primary analysis showed that favourable factors for long-term survival include age < 60 years old, serum CEA < 5 ng/mL, serum CA 19-9 < 37 U/mL, non-cirrhotic liver, tumor size < 2 cm, site of primary tumor, postoperative pancreatic fistula, R0 resection, postoperative chemotherapy, and no recurrence. Multivariate analysis demonstrated that CA 19-9 < 37 U/mL [OR(95% CI) = 1.712(1.24 8–2.34 8), P = 0.001], smaller tumor size [OR(95% CI) = 1.335(1.032–1.726), P = 0.028] and R0 resection [OR(95% CI) = 3.098(2.095–4.582), P < 0.001] were independent factors for survival ≥ 5 years. The prognosis was best for ampullary adenocarcinoma, for which the median survival was 54 months and 5-year survival rate was 39.0%, and the poorest was pancreatic head adenocarcinoma, for which the median survival was 27 months and 5-year survival rate was 7%. Conclusions: The majority of long-term survivors after PD for periampullary adenocarcinoma are patients with ampullary tumor. CA 19-9 < 37 U/mL, smaller tumor size, and R0 resection were found to be independent factors for long-term survival ≥ 5 years.

关键词： Pancreatic carcinoma Pancreatic head carcinoma Pancreaticodudenectomy Long-term survival

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Processing of Ceramic Based Nanocomposite Usingα-Al_2O_3 Powder and FeCl_2 Solution as Starting Materials

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Journal of Materials Science & Technology 2007年第6期23卷 837-842页

作者： mohamed M.el-Sayed Seleman Department of Materials and Metallurgical Engineering Faculty of Petroleum and Mining EngineeringPost Code 43721SuezEgypt

Alumina-iron nanocomposite powders were prepared by a two-step process. In the first step, α-Al2O3-FeCl2 powder mixture was formed by mixing α-Al2O3 powders with FeCl2 solution followed by drying. In the second step, the FeCl2 in the dry power mixture was selectively reduced to iron particles. A reduction temperature of 750℃ for 15 min in dry H2 was chosen based on the thermodynamic calculations. The concentration of iron in FeCl2 solution was calculated to be 20 vol. pct in the final composite. Two techniques were used to produce composite bulk materials. The Al2O3 nanocomposite powders were divided to two batches. The first batch of the produced mixture was hot pressed at 1400℃ and 27 MPa for 30 min in a graphite die. To study the effect of oxygen on the Al2O3/Fe interface bonding and mechanical properties of the composite, the second batch was heat treated in air at 700℃ for 20 min to partially oxidize the iron particles before hot pressing. Characterization of the composites was undertaken by conventional density measurements, X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and electron probe micro analysis （EPMA）. The suggested processing route （mixing, reduction and hot pressing） produces ceramic-metal nanocomposite much tougher than the pure Al2O3. The fracture strength of the produced Al2O3/Fe nanocomposite is nearly twice that of the pure Al2O3. The presence of spinel phase, FeAl204, as thick layer around the Fe particles in the Al2O3 matrix has a detrimental effect on interfacial bonding between Fe and AI203 and the fracture properties of the composite.

关键词： Ferrous chloride Reduction Alumina-iron nanocomposite Spinel phase

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