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Spectrally adapted red flare tracers with superior spectral performance

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Defence Technology（防务技术） 2017年第6期13卷 406-412页

作者： Ramy Sadek mohamed Kassem mohamed abdo Sherif Elbasuney School of Chemical Engineering Military Technical CollegeKobry ElkobaCairoEgypt

The production of bright light, with vivid color, is the primary purpose of signaling, illuminating devices,and fire control purposes. This study, reports on the development of red flame compositions with enhanced performance in terms of luminous intensity, and color quality. The light intensity and the imprint spectra of developed red flame compositions to standard NATO red tracer(R-284 NATO) were measured using digital luxmeter, and UV-Vis. spectrometer. The main giving of this study is that the light intensity of standard NATO red tracer was increased by 72%, the color quality was also improved by60%(over the red band from 650 to 780 nm). This enhanced spectral performance was achieved by means of deriving the combustion process to maximize the formation of red color emitting species in the combustion flame. Thanks to the optimum ratio of color source to color intensifier using aluminum metal fuel; this approach offered the highest intensity and color quality. Upon combustion, aluminum was found to maximize the formation SrCL(the main reactive red color emitting species) and to minimize the interfering incandescent emission resulted from MgO and SrO. Quantification of active red color emitting species in the combustion flame was conducted using chemical equilibrium thermodynamic code named ICT. The improvement in red flare performance, established the rule that the color intensifier should be in the range from 10 to 15 Wt % of the total composition.

关键词： Pyrotechnics Colored flames Tracers Luminous intensity Molecular spectroscopy

Novel yellow colored flame compositions with superior spectral performance

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Defence Technology（防务技术） 2017年第1期13卷 33-39页

作者： Ramy Sadek mohamed Kassem mohamed abdo Sherif Elbasuney School of Chemical Engineering Military Technical CollegeKobry El-KobbaCairoEgypt

The production of colored flames is the primary purpose of military signaling, projectile tracing, and illuminating devices. Certain elements and compounds when heated to high temperature have the unique property of emitting lines or narrow bands in the visible region(380-780 nm). This study, reports on the development of novel yellow colored flame compositions with enhanced spectral performance in terms of luminous intensity, and color quality to standard Russian yellow tracer. The light intensity and the imprint spectra of developed yellow flares were measured using digital luxmeter and UV e Vis. spectrometer respectively. The main giving of this study is that the light intensity, and color quality of Russian yellow tracer were improved by 287%, and 170% respectively. This was accomplished by means of optimizing the ratio of novel binder to color source using aluminum metal fuel. Aluminumbased formulations were found to maximize the formation of yellow reactive emitting specimens, and to eliminate any interfering incandescent emission resulted from Mg O. Quantification of yellow color emitting specimens in the combustion gaseous products was achieved using chemical equilibrium thermodynamic code named ICT(Institute of Chemical Technology in Germany, Virgin 2008); in an attempt to judge the light quality. This improvement in yellow flare performance established the rule that the emission intensity increases as the reaction temperature increases. In the meantime upper limit of temperature was avoided to maximize the color quality.

关键词： Pyrotechnics Colored flames Yellow tracer Atomic spectroscopy Color quality

Novel colored flames via chromaticity of essential colors

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Defence Technology（防务技术） 2019年第2期15卷 210-215页

作者： Ramy Sadek mohamed Kassem mohamed abdo Ahmed Fahd Hesham Tantawy Amir Elsaidy Sherif Elbasuney School of Chemical Engineering Military Technical College

Colored flame compositions have distinctive variety of applications ranging from military signaling,rocket tracking, and illuminating devices. Certain elements and compounds when heated to high temperature are able to emit unique wavelengths in the visible region. This study, reports on the development of novel colored flames that cannot be generated by emitting atomic/molecular species. This was achieved by using chromaticity of basic colored flames. Mixing of high quality primary colored flames including Blue, Yellow, and Red in proper ratio was conducted; any interfering incandescent emission resulted from MgO was eliminated using Al metal fuel. The spectral characteristics in terms of luminous intensity, and color quality were evaluated using digital luxmeter and UV-Vis. spectrometer *** quality mixed colored flames include violet, sweet pink, and marigold were developed. This study shaded the light on the state of the art for the real development of novel colored flame compositions and chromaticity of basic colored flames.

关键词： Pyrotechnics Colored flame Atomic spectroscopy Molecular spectroscopy Luminous intensity Color quality Chromaticity

Toxoplasma gondii infection can induce retinal DNA damage: an experimental study

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International Journal of Ophthalmology(English edition) 2014年第3期7卷 431-436页

作者： Nagwa Mostafa El-Sayed eman mohamed Aly Department of Medical Parasitology Research Institute of Ophthalmology Department of Basic Science Biophysics and Laser Science Unit Research Institute of Ophthalmology

AIM:To detect whether Toxoplasma gondii(***)infection of mice can induce retinal DNA ***:A total of 20 laboratory-bred male Swiss albino mice were used and divided into four groups:control group(non-infected animals);*** infected group;immunosuppressed infected group;and infected group treated with sulfadiazine and *** eyes were collected 6wk post infection and retinas were *** retina was immediately processed for comet assay and the frequency of tailed nuclei(DNA damage)was *** addition,retinal DNA damage was revealed by various comet assay parameters that were provided by the image analysis software including tail length,percentage of DNA in the tail,percentage of tailed cells and tail ***:The obtained results showed that *** infection induced a statistically significant increase in the frequency of tailed nuclei,tail length,percentage of DNA in the tail,and tail moment in mice retinal cells compared to the control group(which showed some degree of DNA damage).In immunosuppressed infected group,retinal DNA damage was severing and there was significant increase in various comet assay parameters compared to both control and infected *** treatment with sulfadiazine and pyrimethamine,retinal DNA damage decreased and all comet assay parameters showed a statistical significant decrease compared to infected ***:*** infection can induce DNA damage in mice retinal cells.

关键词： Toxoplasma gondii retinochoroiditis DNA damage comet assay

Vital Parameters Assessments of Starvation Tolerance of in vitro Populus alba Culture

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Phyton-International Journal of Experimental Botany 2022年第4期91卷 889-902页

作者： mohamed Fathy Ahmed eman Zakaria Ahmed Salman Aloufi Mohammed Alqurashi Amal Alyamani eman Fayad eman Tawfik Hussien Horticulture Department Faculty of AgricultureAin Shams UniversityCairo11566Egypt Botany and Microbiology Department Faculty of ScienceHelwan UniversityCairo11795Egypt Department of Biotechnology Faculty of SciencesTaif UniversityTaif21944Saudi Arabia

Populus alba is a large woody deciduous *** plant has been introduced to shooting,then multiplication of rooting on Murashige and Skoog(MS)*** work was designed to estimate the effect of two factors(low levels of 1-Naphthaleneacetic acid NAA and sucrose)on *** response resulting in 6 treatments compared to the control,with twelve measured *** was a significant difference in some measurements in morphology,like plantlets fresh-weight,shoot-,root-length,and leaf *** the physiological measurements,there were significant differences in all the measured *** low concentrations of sucrose and media composition/power(MS grams/L)led to starvation in plants;however,these conditions led to enhancement in some morphological and physiological parameters to overcome the starvation effect,compared to the *** RAPD-PCR molecular marker(four decamers)was used to evaluate the new individuals’genetic variation(instability),resulting in a total polymorphism percentage of 50.83%.It was formerly known that the plantlets were identical to each other and to the mother *** this study,however,the use of distinct media power,hormonal and sucrose levels resulted in molecular variation reflected in ***’s morphological and physiological responses.

关键词： Genetic stability Populus alba RAPD-PCR somaclonal variations starvation

Streptococcus peumoniae in an Egyptian urban community:incidence of erythromycin-resistance determinants and antibiotic susceptibility profile

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Asian Pacific Journal of Tropical Medicine 2008年第4期1卷 20-23页

作者： Fatma Abdelaziz Amer eman mohamed Elbehedy mohamed Elahmady Microbiology and Immunology Department Faculty of PharmacySinai UniversitySinaiEgypt Microbiology & Immunology Department Faculty of MedicineZagazig UniversityZagazigEgypt

Objectives:To determine the incidence of resistance of Streptococcus(Strep).pneumoniae isolated in our locality to erythromycin,to screen for the two resistance determinants erm(B) and mef(A) genes,and to identify the susceptibility profile to commonly used ***:Samples were collected from patients attending the Outpatient Department of Zagazig University Hospital,Zagazig,Egypt,between February 2006 and March *** was identified by conventional *** to erythromycin and 15 antibiotics were identified by disc diffusion method,as outlined by CLSI.E-test was used for MIC determination of ***(B) and mef(A) genes were detected by ***:Eighty-one Strep. pneumoniae strains were ***- one of them(63%) were erythromycin-resistant,and mef(A) gene was the predominant resistance ***,imipenem and gatifloxacin had the best activity against the isolates,whereas tetracycline had the ***-two(51.85%) out of the 81 *** strains were ***:High incidence of resistance to erythromycin and multiple antimicrobials ***(A) was the principal erythromycin-resistance gene.

关键词： Strep,pneumoniae Erythromycin erm.(B) gene mef(A) gene Antibiotic resistance Egypt

Maximizing the Benefit of Rate Transient Analysis for Gas Condensate Reservoirs

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Energy Engineering 2021年第5期118卷 1411-1423页

作者： Mahmoud abdo Tantawy Ahmed A.M.Elgibaly Ahmed mohamed Farag Faculty of Petroleum and Mining Engineering Suez UniversitySuezEgypt Abu Qir Petroleum Company AlexandriaEgypt

In recent years,many trials have been made to use the Rate Transient Analysis(RTA)techniques as a method to describe the gas condensate *** problem with using these techniques is the multi-phase behavior of the gas condensate ***,the Pressure Transient Analysis(PTA)is commonly used in this case to analyze the reservoir *** this paper,we are going to compare the results of both PTA and RTA of three wells in gas condensate *** comparison showed a great match between the results of the two mentioned techniques for the first time using a reference GOR of 75,000 SCF/***,we concluded that we could depend on RTA instead of PTA to spare the cost associated with the PTA in the gas condensate reservoirs.

关键词： Rate transient analysis production data analysis well testing permeability skin factor gas condensate

Liver stiffness as a predictor of hepatocellular carcinoma behavior in patients with hepatitis C related liver cirrhosis

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Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 22-28页

作者： Sameh A Lashen mohamed M Elshafei Fahmy H Hablass eman A Alsayed Asmaa A Hassan Department of Internal Medicine Faculty of MedicineUniversity of AlexandriaAlexandriaEgypt Department of Radiology Faculty of MedicineUniversity of AlexandriaAlexandriaEgypt Department of Biomedical Informatics and Medical Statistics Medical Research InstituteUniversity of AlexandriaAlexandriaEgypt

Background: Risk strati cation and prognostication of hepatocellular carcinoma (HCC) help to improve patient outcome. Herein we investigated the role of liver stiffness measurement (LSM) in the prediction of HCC behavior. Methods: Totally 121 na ve patients with HCC were included. HCC radiological evaluation and staging were done. LSM was measured using virtual touch quanti cation. Patients were divided into early to intermediate HCC (BCLC-0, A and B) and late HCC (BCLCC and D). HCC was treated according to the BCLC stage. HCC recurrence-free interval was estimated. Results: The mean LSM inside the tumor was signi cantly lower than the peri-tumoral area and the cirrhotic non-cancerous liver parts (P<0.001). In late HCCs stage, the mean LSM inside the tumor and in the peri-tumoral tissue was lower than the corresponding values in the early to intermediate HCCs stage (P<0.001). LSM inside the tumor and in the peri-tumoral tissue negatively correlated with serum AFP, tumor vascular invasion, and stage (P<0.05). The recurrence-free interval was directly correlated to LSM inside the tumor and inversely to LSM in cirrhotic non tumorous liver part. Kaplan-Meier analysis showed that the recurrence-free interval was signi cantly longer in patients with LSM inside the tumor of ≥1.25m/s compared to those with LSM inside the tumor of<1.25m/s. Conclusions: LSM can serve as a potential non-invasive predictor for HCC clinical behavior and the recurrence-free interval following loco-regional treatments.

关键词： Fibrosis Hepatitis C Hepatocellular carcinoma Point shear wave Liver cirrhosis

Synthesis, Structural Characterization, and Antimicrobial Activities of Mn（II）, Co（II）, Ni（II）, Cu（ll） and Zn（II） Complexes of Triazole-based Azodyes

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Chinese Journal of Chemistry 2011年第6期29卷 1124-1132页

作者： Khedr, Abdalla M. Gaber, mohamed Abd EI-Zaher, eman H. Chemistry Department Faculty of Science Tanta University Tanta Egypt Botany Department Faculty of Science Tanta University Tanta Egypt

The synthesis and characterization of new transition metal complexes of Mn（ll）, Co（II）, Ni（II）, Cu（II） and Zn（II） with 3-（2-hydroxynaph-l-ylazo）-1,2,4-triazole （HL1） and 3-（2-hydroxy-3-carboxynaph-l-ylazo）-1,2,4-triazole （HL2） have been carried out. Their structures were confirmed by elemental analyses, thermal analyses, spectral and magnetic data. The IR and 1H NMR spectra indicated that HL1 and HL2 coordinated to the metal ions as bidentate monobasic ligands via the hydroxyl O and azo N atoms. The UV-Vis, ESR spectra and magnetic moment data revealed the formation of octahedral complexes [MnL1（AcO）（H2O）3] （1）, [CoL1（AcO）（HzO）3]·H2O （2）, [MnL2- （AcO）（H20）3] （6） and [CoL2（AcO）（H2O）3] （7）, [NiL1（AcO）（H2O）] （3）,[ZnLI（AcO）（HzO）]·H2O （5）, [NiL2- （AcO）（H2O）] （8）, [ZnL2（AcO）（H2O）]·H2O （10） have tetrahedral geometry, whereas [CuLI（AcO）（H2O）2] （4） and [CuL2（AcO）（H2O）2]·5H2O （9） have square pyramidal geometry.. The mass spectra of the complexes under EI-con- ditions showed the highest peaks corresponding to their molecular weights, based on the atomic weights of 55Mn, 59Co, 58Ni, 63Cu and 64Zn isotopes; besides, other peaks containing other isotopes distribution of the metal. Kinetic and thermodynamic parameters of the thermal decomposition stages were computed from the thermal data using Coats-Redfern method. HL2 and complexes 6--10 were found to have moderate antimicrobial activities against Staphylococcus＇ aureus （gram positive）, Escherichia coli （gram negative） and Salmonella sp bacteria, and antifungal activity against Fusarium oxysporum, Aspergillus niger and Candida albicans. Also, in most cases, metallation increased the activity compared with the free ligand.

关键词： analytical and inorganic chemistry triazole azodyes metal(II) chelates antimicrobial activities