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Defence Technology（防务技术） 2021年第5期17卷 1609-1616页

作者： Hany S.Ayoub Ashraf f.el-sherif Ahmed elbeih Department of Physics Faculty of ScienceCairo UniversityEgypt Laser Photonics Research Center Engineering Physics DepartmentMilitary Technical CollegeCairoEgypt Explosives Department Military Technical CollegeKobry ElkobbahCairoEgypt

cis-1,3,4,6-Tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHmX)is an advanced energetic compound that expected to spread worldwide in the near ***,no approved remote detection methods were reported in current literature for this material,we performed hyper-spectral imaging and laser induced fluorescence(LIf)to a BCHmX sample under low laser fluence for determining the optimum laser wavelength used in any future BCHmX-LIf based remote detection *** this purpose,an experimental setup consisted of a sun spectrum lamp and hyper-spectral camera was built to illuminate and image white powder samples of BCHmX in comparison with the traditional explosives,HmX(1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane),RDX(1,3,5-trinitro-1,3,5-triazacyclohexane),PETN(2,2-Bis[(nitroxy)methyl]propane-1,3-diyldinitrate).The imaging reveals strong BCHmX sample absorption contrast among other samples at wavelength ranging from 400 to 410 *** light source was replaced by a 405 nm laser diode illuminator,a strong BCHmX sample LIf at the spectral range from 425 to 700 nm was observed under low laser fluence condition of 0.1 mJ/cm^(2).finally,we demonstrated successfully the ability of the 405 nm LIf and the hyperspectral imaging technique to detect finger print traces of BCHmX on white cellulose fabric from a distance of 15 m and a detection limit of 1 mg/cm^(2).

关键词： Hyperspectral imaging Remote trace detection BCHmX Laser induced fluorescence

Analysis of magnetic Resistive flow of Generalized Brinkman Type Nanofluid Containing Carbon Nanotubes with Ramped Heating

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Computers, materials & Continua 2021年第4期67卷 1069-1084页

作者： muhammad Saqib Ilyas Khan Sharidan Shafie Ahmad Qushairi mohamad el-Sayed m.sherif Department of mathematical Sciences Faculty of ScienceUniversiti Teknologi MalaysiaJohor Bahru81310Malaysia faculty of mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Center of Excellence for Research in Engineering materials(CEREm) King Saud UniversityAl-Riyadh11421Saudi Arabia Department of Physical Chemistry Electrochemistry and Corrosion LaboratoryNational Research CentreCairo12622Egypt

In recent times,scientists and engineers have been most attracted to electrically conducted nanofluids due to their numerous applications in various fields of science and *** example,they are used in cancer treatment(hyperthermia),magnetic resonance imaging(mRI),drugdelivery,and magnetic refrigeration(mR).Bearing in mind the significance and importance of electrically conducted nanofluids,this article aims to study an electrically conducted water-based nanofluid containing carbon nanotubes(CNTs).CNTs are of two types,single-wall carbon nanotubes(SWCNTs)and multiple-wall carbon nanotubes(mWCNTs).The CNTs(SWCNTs and mWCNTs)have been dispersed in regular water as base fluid to form waterCNTs *** Brinkman Type nanofluid model is developed in terms of time-fractional *** ramped heating and sinusoidal oscillations conditions have been taken at the *** model has been solved for exact analytical solutions via the fractional Laplace transform *** exact solutions have been graphically studied to explore the physics of various pertinent flow parameters on velocity and temperature *** empirical results reveal that the temperature and velocity fields decreased with increasing values of fractional parameters due to variation in thermal and momentum boundary *** is also indicated that the isothermal velocity and temperature are higher than ramped velocity and temperature.

关键词： Nanofluid fractional derivatives Brinkman type fluid exact solutions

Diode Pumped High Peak Power Quasi Q-Switched and Passively Q-Switched Nd:YVO<sub>4</sub>Lasers at 1064 nm and 532 nm using Cr:YAG and KTP crystals

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Optics and Photonics Journal 2013年第1期3卷 51-62页

作者： Ashraf f. el-sherif mahmoud m. Talat military Technical Institute Cairo Egypt Townes Laser Institute CREOL College of Optics and Photonics University of Central Florida Orlando USA

Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at fWHm and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at fWHm and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time.

关键词： High Power Diode Laser High Power Nd:YVO4 Laser Cr:YAG Saturable Absorber mirror Passive Q-Switching KTP Crystal Self Q-Switching Special Cooling System

Can We Predict menorrhagia with Intrauterine Contraceptive Device (IUCD) Insertion?

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Open Journal of Obstetrics and Gynecology 2017年第7期7卷 753-766页

作者： Ghada m. mansour sherif H. Hussein Haitham f. mohammed sherif.f. el m.kkawy sherif A. Akl Asmaa A. Abd el Dayem Department of Obstetrics and Gynecology Ain Shams University Cairo Egypt Ashmoun Hospital Ministry of Health Hospitals Cairo Egypt

Objective: Studying sub endometrial vascularity and blood flow in cases using intrauterine contraceptive devices for contraception with and without menorrhagia compared to cases not using intrauterine contraceptive devices. methods: Three hundred and fifteen women attending gynecology and family planning outpatient clinics in the maternity hospital, Ain Shams University were included in the study. They were classified into three groups, 105 women using IUCD with menorrhagia (group I), 105 women using IUCD without menorrhagia (group II), and 105 normal controls not using IUCD (group III). After excluding local causes for bleeding, blood disease or any medical disorders, transvaginal ultrasound including three dimensional power Doppler (3DPD) ultrasound was done for all women. Right and left uterine artery pulsatility index (PI) and resistance index (RI) were calculated, subednometrial blood flow RI and PI were obtained then 3DPD Vascular indices (VI, fI and VfI) of subendometrial blood flow were obtained for all cases. Statistical analysis was done to compare between the three groups. Results: A significant statistical difference was found as regards subendometrial vascularity indices, while there was no difference as regards bilateral uterine arteries Doppler indices in the three groups. Conclusion: Subendometrial vascularity in cases of menorrhagia with IUCD was markedly higher than in cases without menorrhagia and cases with no IUCD. 3DPD may be used for selection of cases prior to insertion of IUCD.

关键词： Intrauterine Contraceptive Devices IUCD 3D Power Doppler Ultrasound menorrhagia

Autologous CD34^+ and CD133^+ stem cells transplantation in patients with end stage liver disease

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World Journal of Gastroenterology 2010年第42期16卷 5297-5305页

作者： Hosny Salama Abdel-Rahman N Zekri Abeer A Bahnassy Eman medhat Hanan A Halim Ola S Ahmed Ghada mohamed Sheren A Al Alim Ghada m sherif Tropical medicine Department El-Kasr Al-Aini School of MedicineKasr Al-Aini st.Kasr AlAini11977 CairoEgypt Virology and Immunology Unit Cancer Biology DepartmentNational Cancer InstituteCairo UniversityKasr Al-Aini st.Fom El-Khaleeg11976 CairoEgypt Pathology Department National Cancer InstituteCairo UniversityKasr Al-Aini st.Fom El-Khaleg11976 CairoEgypt Biostatistics and Epidemiology Department National Cancer InstituteCairo University11976 CairoEgypt

AIm:To assess the utility of an autologous CD34 + and CD133 + stem cells infusion as a possible therapeutic modality in patients with end-stage liver ***:One hundred and forty patients with endstage liver diseases were randomized into two *** 1,comprising 90 patients,received granulocyte colony stimulating factor for five days followed by autologous CD34 + and CD133 + stem cell infusion in the portal *** 2,comprising 50 patients,received regular liver treatment only and served as a control ***:Near normalization of liver enzymes and improvement in synthetic function were observed in 54.5% of the group 1 patients;13.6% of the patients showed stable states in the infused *** of the patients in the control group showed *** adverse effects were ***:Our data showed that a CD34 + and CD133 + stem cells infusion can be used as supportive treatment for end-stage liver disease with satisfactory tolerability.

关键词： CD34 CD133 Stem cell Liver Hepatitis C virus

Diffusion-Weighted mR Imaging of the Benign Hepatic focal Lesions

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Open Journal of Radiology 2014年第1期4卷 136-143页

作者： Adel el-Badrawy Germeen Albair Ashmallah Ahmed mohamed Tawfik sherif Abdelfattah manal Salah-eldin Emad eldin Azmy Amro Awad el-Karef Ghada A. Salem Omar farouk Clinical Hematology Department Faculty of Medicine Mansoura University Mansoura Egypt Department of Surgical Oncology Faculty of Medicine Mansoura University Mansoura Egypt medical Oncology Department Faculty of Medicine Mansoura University Mansoura Egypt Pathology Department Faculty of Medicine Mansoura University Mansoura Egypt Radiology Department Faculty of Medicine Mansoura University Mansoura Egypt Tropical medicine Department Faculty of Medicine Zagazig University Egypt

Purpose: To determine the role of diffusion weighted mR imaging and apparent diffusion coefficient (ADC) in benign hepatic focal lesions. method and materials: This study included 47 patients (29 m, 18 f with mean age of 43 years) with benign hepatic focal lesions. They were cyst (n = 8), hemangioma (n = 23), abscess (n = 5), adenoma (n = 5), focal nodular hyperplasia (n = 4) and nodular regenerative hyperplasia (n = 2). They underwent routine mR imaging and diffusion mR weighted imaging using 1.5 tesla mR unit (Symphony-Siemens). Diffusion mR imaging was done using spin echo type of single shot echo planar imaging (EPI) with b value of 0, 500 & 1000 sec/mm2. The apparent diffusion coefficient (ADC) map was reconstructed and ADC value was measured. The mean ADC values correlated with histo-pathological results as well as follow-up imaging results. Results: Adequate ADC maps were obtained in 47 patients. The mean ADC values were 3.4 ± 0.12 × 10-3 mm2/sec in cystic lesion, 2.23 ± 0.08 × 10-3 mm2/sec in hemangioma, 1.94 ± 0.05 × 10-3 mm2/sec in abscess, 1.72 ± 0.07 × 10-3 in focal nodular hyperplasia, 1.65 ± 0.06 × 10-3 mm2/sec in adenoma, 1.62 ± 0.07 × 10-3 mm2/sec in nodular regenerative hyperplasia. The mean ADC values were significantly different within benign hepatic focal lesions (P fferences between the mean ADC values of fNH, adenoma and NRH were not statistically significant (P ffusion weighted mR imaging is a new imaging modality for diagnosis and characterization of different benign hepatic focal lesions, particularly in patient with renal dysfunction.

关键词： Diffusion mR Imaging Apparent Diffusion Coefficient Benign Hepatic focal Lesion