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Effect of energy content of the nitraminic plastic bonded explosives on their performance and sensitivity characteristics

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Defence Technology（防务技术） 2019年第4期15卷 488-494页

作者： Svatopluk Zeman ahmed k. Hussein Marcela Jungova ahmed Elbeih Institute of Enegetic Materials Faculty of Chemical Technology University of Pardubice CZ-532 10 Pardubice Czechia Military Technical College Kobry Elkobbah Cairo Egypt

Information about the forty nine nitraminic plastic bonded explosives(PBXs)and different nitramines were *** of these PBXs are nitramines 1,3,5-trinitro-1,3,5-triazinane(RDX)and β-1,3,5,7-tetranitro-1,3,5-tetrazocane(β-HMX),cis-1,3,4,6-tetranitro-octahydroimidazo-[4,5-d]imidazole(bicyclo-HMX,BCHMX)and e-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(e-HNIW,CL-20)which are bonded by polyfluoro-elastomers,polydimethyl-siloxane,poly-glycidyl azide,polyisobutylene,polystyrene-butadiene,poly-acrylonitrile-butadiene and hydroxyl-terminated polybutadiene in addition to a melt cast compositions based on 2,4,*** thirty two of these PBXs the relationships are specified and analyzed between heats of their combustion and relative explosive strengths;by means of these relationships it might be possible to estimate,which groupings in the macromolecule of binder could be liable to their primary fission in the PBXs ***,for forty two of these explosives,the relationships are described and analyzed between their enthalpies of formation and impact sensitivities;here is especially attention paid to PBXs filled by *** rate constants from Vacuum Stability Test(VST)of four nitramines and twenty PBXs are introduced into relationships with their enthalpies of *** to all the mentioned cases,increasing of energy content of the studied explosives leads to increase of the relative explosive strength or initiation reactivity,*** with the opposite trend,the outputs of VST are for BCHMX,where in PBXs are matrices with the esteric plasticizers or the energetic poly-glycidyl *** of RDX or HMX,respectively,into the BCHX PBXs gives ternary PBXs whose thermal stability,in the sense of applied VST,is higher comparing to the original binary explosives.

关键词： Enthalpy Explosive strength Combustion Nitramines PBX Thermal stability

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Thyme oil inclusion levels in a rabbit ration: Evaluation of productive performance, carcass criteria and meat quality under hot environmental conditions

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Animal Nutrition 2018年第4期4卷 410-416页

作者： ahmed A.A.Abdel-Wareth Eman M.M.taha karl-Heinz Südekum Jayant Lohakare Department of Animal and Poultry Production Faculty of Agriculture South Valley University Department of Food Science and Technology Faculty of Agriculture South Valley University Institute of Animal Science University of Bonn Department of Agriculture-Animal Science University of Arkansas at Pine Bluff

The aim of this study was to determine the impact of thyme essential oil supplementation in rabbit rations on performance, carcass criteria, and meat quality under hot environmental conditions. A total of 75, 4-week-old Californian male rabbits were assigned to 5 dietary treatments until 12 weeks of *** rabbits were reared in an open house system(38C average ambient temperature and 26% to 35%relative humidity). Treatments were as follows: unsupplemented standard ration, negative control(CON); standard ration supplemented with 1.50 g/kg olive oil as carrier, positive control(POS);POS t 50 mg/kg thyme oil(TO1); POS t 100 mg/kg thyme oil(TO2); and POS t 150 mg/kg thyme oil(TO3). Dietary thyme oil up to 150 mg/kg improved(P ke and growth performance in comparison to CON. The highest average daily gain and most efficient feed conversion ratio(linear,P kg using 1.50 g/kg olive oil as a carrier can be used as an efficient feed additive for improving productive performance of rabbits under hot environmental conditions.

关键词： Antioxidant Essential oil Meat characteristics Nutrition Production

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In-hospital outcomes of transapical versus surgical aortic valve replacement: from the U.S. national inpatient sample

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Journal of Geriatric Cardiology 2021年第9期18卷 702-710页

作者： Ashraf Abugroun Osama Hallak ahmed taha Alejandro Sanchez-Nadales Saria Awadalla Hussein Daoud Efehi Igbinomwanhia Lloyd W klein Department of Internal Medicine Medical College of Wisconsin(MCW)WIUSA Division of Cardiology Ketter-ing Medical CenterOHUSA Department of Internal Medicine School of MedicineIndiana UniversityIndianapolisIndianaUSA Department of Cardiovascular Disease Cleveland Clinic FloridaFLUSA Division of Epidemiology&Biostatistics University of Illinois-ChicagoILUSA Division of Cardiology Creighton UniversityNEUSA Department of Cardiology Case Western Reserve University(MetroHealth)OHUSA University of California San Francisco(UCSF)San FranciscoCAUSA

OBJECTIVE To compare the outcomes of transapical transcatheter aortic valve replacement(TA-TAVR)and surgical aortic valve replacement(SAVR)using a large US population *** The *** Inpatient Sample was queried for all patients who underwent TA-TAVR or SAVR during the *** primary outcome was all-cause in-hospital *** outcomes were in-hospital stroke,pericardiocentesis,pacemaker insertion,mechanical ventilation,vascular complications,major bleeding,acute kidney injury,length of stay,and cost of *** were modeled using multi-variable logistic regression for binary outcomes and generalized linear models for continuous *** A total of 1560 TA-TAVR and 44,280 SAVR patients were *** who underwent TA-TAVR were older and *** to SAVR,TA-TAVR correlated with a higher mortality(4.5%vs.2.7%,effect size(SMD)=0.1)and higher periprocedural *** multivariable analysis,both TA-TAVR and SAVR had a similar adjusted risk for in-hospital ***-TAVR correlated with lower odds of bleeding with(adjusted OR(aOR)=0.26;95%CI:0.18-0.38;Pk-adjusted analysis showed that TA-TAVR has no advantage over SAVR except for patients with chronic lung disease where TA-TAVR has higher mortality.

关键词： logistic In-hospital outcomes of transapical versus surgical aortic valve replacement from the U.S national inpatient sample

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Solitary kinetic Alfven waves in dense plasmas with relativistic degenerate electrons and positrons

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Plasma Science and Technology 2019年第4期21卷 85-93页

作者： Monzurul k ahmed Om P SAH Department of Physics Biijhora MahavidyalayaBongaigaon-783380AssamIndia

Propagation of solitary kinetic Alfven waves(kAWs)is investigated in small but finite/3(particle-to-magnetic pressure ratio)collisionless dense plasma whose constituents are non degenerate wann ions,and relativistic degenerate electrons and *** the use of reductive perturbation technique,kortweg-de Vries equation is derived to obtain small amplitude localized wave solution of *** effects of plasma 0,positron concentration,electron relativistic degeneracy parameter,ion thermal temperature and obliqueness parameter on solitary kAWs are *** results of this theoretical investigation are aimed at elucidating characteristics of kinetic Alfven solitary waves in relativistic degenerate e-p-i plasmas found in dense astrophysical objects specifically neutron stars and white dwarfs.

关键词： solitary kinetic Alfven waves dense plasmas electron-positron-ion plasma,relativistic degenerate plasma reductive perturbation technique

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Solitary kinetic Alfvén waves in a dense electron–positron–ion plasma with degenerate electrons and positrons

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Plasma Science and Technology 2017年第12期19卷 42-49页

作者： Monzurul k ahmed Om P SAH Depatment of Physics Birjhora MahavidyalayaBongaigaon-783380AssamIndia

Through the use of a reductive perturbation technique, solitary kinetic Alfvén waves（kAWs） are investigated in a low but finite b（particle-to-magnetic pressure ratio） dense electron–positron–ion plasma where electrons and positrons are degenerate. The degenerate plasma model considered here permits the existence of sub-Alfvénic compressive solitary kAWs. The influence of r（equilibrium positron-to-ion density ratio）, sF（electron-to-positron Fermi temperature ratio）, b and obliqueness parameter lzon various characteristics of solitary kAWs are examined through numerical plots. We have shown that there exists a critical value of lzat which a soliton width attains its maximum value which decreases with an increase in r and *** is also found that solitons with a higher energy propagate more obliquely in the direction of an ambient magnetic field. The results of the present investigation may be useful for understanding low frequency nonlinear electromagnetic wave propagation in magnetized electron–positron–ion plasmas in dense stars. Specifically, the relevance of our investigation to a pulsar magnetosphere is emphasized.

关键词： kinetic Alfvén waves solitons electron–positron–ion plasma degenerate plasma Thomas–Fermi approximation

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Connected Components-based Colour Image Representations of Vibrations for a Two-stage Fault Diagnosis of Roller Bearings Using Convolutional Neural Networks

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 73-93页

作者： Hosameldin O.A.ahmed Asoke k Nandi Department of Electronic and Electrical Engineering Brunel University LondonUxbridge UB83PHUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’anChina

Roller bearing failure is one of the most common faults in rotating *** techniques for bearing fault diagnosis based on faults feature extraction have been *** feature extraction from fault signals requires expert prior information and human ***,deep learning algorithms have been applied extensively in the condition monitoring of rotating machines to learn features automatically from the input *** its robust performance in image recognition,the convolutional neural network(CNN)architecture has been widely used to learn automatically discriminative features from vibration images and classify health *** paper proposes and evaluates a two-stage method RGBVI-CNN for roller bearings fault *** first stage in the proposed method is to generate the RGB vibration images(RGBVIs)from the input vibration *** begin this process,first,the 1-D vibration signals were converted to 2-D grayscale vibration *** the conversion was completed,the regions of interest(ROI)were found in the converted 2-D grayscale vibration ***,to produce vibration images with more discriminative characteristics,an algorithm was applied to the 2-D grayscale vibration images to produce connected components-based RGB vibration images(RGBVIs)with sets of colours and texture *** the second stage,with these RGBVIs a CNN-based architecture was employed to learn automatically features from the RGBVIs and to classify bearing health *** cases of fault classification of rolling element bearings are used to validate the proposed *** results of this investigation demonstrate that RGBVI-CNN can generate advantageous health condition features from bearing vibration signals and classify the health conditions under different working loads with high ***,several classification models trained using RGBVI-CNN offered high performance in the testing results of the overall classification accura

关键词： Bearing fault diagnosis Image representation of vibrations Deep learning Convolutional neural networks

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An energetic nano-fiber composite based on polystyrene and 1,3,5-trinitro-1,3,5-triazinane fabricated via electrospinning technique

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Defence Technology(防务技术) 2023年第9期27卷 1-8页

作者： Mahmoud Abdelhafiz ahmed k.Hussein Waleed F.khalil ahmed Elbeih Military TechnicalCollege(MTC) KobryElkobbahCairoEgypt Safety FuelCycleDepartment NRSRCEgyptianAtomicEnergyAuthority(EAEA)CairoEgypt

Electrospinning is a simple technique used to fabricate polymeric nano-fibrous *** nano-fibers have found a wide range of valuable applications in the biomedical ***,it has not been utilized with solid high explosives ***,the electrospinning technique has been used to fabricate polystyrene(PS)/1,3,5-trinitro-1,3,5-triazinane(RDX)composite *** governed electrospinning parameters,voltage,distance from the collector,flow rate,mandrel rotating speed,time,and solution concentration,that greatly affect the morphology of the obtained nanofibers were *** fabricated PS/RDX nano-fibers were characterized using scanning electron microscopy(SEM),X-ray diffractometer(XRD),and Fourier Transform Infrared(FTIR)*** impact and friction sensitivities of PS/RDX were also *** thermal behavior of the prepared composite and the pure materials were studied by the thermal gravimetric analysis technique(TGA).SEM results proved the fabrication of PS/RDX fibers in the nano-size via *** spectroscopy confirmed the existence of the characteristic functional groups of both PS and RDX in the composite *** sharp peaks showed the conversion of amorphous PS into crystalline shape via electrospinning and also confirmed the formation of PS/RDX *** PS fibers absorbed the heat and increased the onset decomposition of the pure RDX from 181.5 to 200.7℃in the case of PS/RDX ***,PS/RDX nano-fibers showed the relatively low impact and friction sensitivities of 100 J and 360 N *** results could introduce PS/RDX nanofibrous composite in the field of explosives detection with high levels of safety.

关键词： Electrospinning Nano-fibers 1,3,5-Trinitro-1,3,5-triazinane(RDX) Polystyrene(PS) Sensitivity

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Evaluation of GALAD Score in Diagnosis and Follow-up of Hepatocellular Carcinoma after Local Ablative Therapy

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Journal of Clinical and Translational Hepatology 2023年第2期11卷 334-340页

作者： Rasha Eletreby Marwa Elsharkawy Alaa Awad taha Mohamed Hassany Amr Abdelazeem Mohamed El-kassas ahmed Soliman Endemic Medicine Department Faculty of MedicineCairo UniversityCairoEgypt Clinical and Chemical Pathology Department Faculty of MedicineCairo UniversityCairoEgypt Hepatogastroenterology Department Theodore Bilharz Research InstituteGizaEgypt Hepatogastroenterology Department National Hepatology and Tropical Medicine Research InstituteCairoEgypt Endemic Medicine Department Faculty of MedicineHelwan UniversityCairoEgypt

Background and Aims:Strategies for detection of early hepatocellular carcinoma(HCC)are still *** GALAD score is a serum biomarker-based model designed to predict the probability of having *** aimed to assess the ability of GALAD score to diagnose early HCC and its validity to follow patients after local ablation ***:This multicenter prospective study included 108 patients in two groups,58 HCC patients(67 focal lesions)with local ablative therapy(study group),and a control group of 50 patients with liver *** GALAD scores of the study and control groups,and of the HCC patients before and after ablative therapy were ***:Most patients were men(74.1%in study group and 76%in controls)with hepatitis C virus infection(98.30%in the study group,and 94%in controls).GALAD scores were significantly higher in HCC patients than in those with benign cirrhosis(2.65 vs.−0.37,p=0.001).Ablative therapy was successful in 94.4%of focal lesions<2 cm,and in 86.10%of 2–5 cm *** GALAD score was also significantly lower at 1 month after ablation in patients with well-ablated tumors(2.19 vs.0.98,p=0.001).The best cutoff values of GALAD score for diagnosis of early HCC,and for prediction of well ablation of HCC were 0.74 and≤3.31(areas under the curve of 0.92 and 0.75,sensitivities of 84.48%and 76.19%,specificities of 89.13%and 83.33%,positive predictive values of 90.74%and 94.1%,and negative predictive values of 82%and 35.7%respectively).Conclusion:The GALAD score was effective for the diagnosis of early HCC and for followup after ablative therapy.

关键词： GALAD score HCC Ablative therapy Liver cirrhosis Egypt

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Preparation and Properties of PBXs Based on FOX-7 in Controlled Fragmentation Warhead Application

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含能材料 2018年第10期26卷 843-849页

作者： karim k Elsharkawy Lin Guo ahmed M Enew School of Chemistry and Environment Beijing University of Aeronautics and Astronautics Chemical Department Faculty of EngineeringCairo University

Polymer bonded explosive(PBX)formulations were successfully prepared in the laboratory scale containing 1,1-diamino-2,2-dinitroethene(FOX-7)and hexogen(RDX)as brisant high explosives and different binder types of polyurethane(PU)based on glycidyl azide polymer(GAP) and hydroxyl-terminated polybutadiene(HTPB) as an energetic and inert polymeric binder *** technique was used for the preparation of different PBX formulations based on FOX-7/RDX and PU(GAP/HTPB)with 14% *** sensitivity to different initial impulses and performance characteristics of the explosive and lethal zone of the tested controlled fragmentation warhead by the fragmentation warhead assessment test(arena test)were studied,in which the arena test was carried out with a controlled fragmentation warhead made from Ck45 steel,with dimensions(100 mm length,30 mm outer diameter and 3 mm thickness).Results show that PBXGF4 has lower sensitivity to impact and heat than those of PBXGR4 by 188.4% and 3.2% *** friction sensitivity is the same as that of *** has better performance,in which detonation velocity increases by 2.1% and brisance increases by 0.5% when compared with those of *** was concluded that PBXGF4 which based on FOX-7 bonded with PU/GAP matrix has good characteristics as PBX,specially in the sensitivity to impact and can be applied for replacing PBXs based on RDX in the advanced PBXs for low sensitive fragmentation warheads.

关键词： polymer bonded explosive(PBX) controlled fragmentation warhead 1,1-diamino-2,2-dinitroethene(FOX-7) hexo-gen(RDX) preparation sensitivity performance characterization arena test

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First United Arab Emirates consensus on diagnosis and management of inflammatory bowel diseases:A 2020 Delphi consensus

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World Journal of Gastroenterology 2020年第43期26卷 6710-6769页

作者： Maryam Alkhatry Ahmad Al-Rifai Vito Annese Filippos Georgopoulos Ahmad N Jazzar ahmed M khassouan Zaher koutoubi Rahul Nathwani Mazen S taha Jimmy k Limdi Gastroenterology and Endoscopy Department Ibrahim Bin Hamad Obaid Allah HospitalMinistry of Health and PreventionRas Al KhaimanUnited Arab Emirates Department of Gastroenterology Sheikh Shakbout Medical CityAbu DhabiUnited Arab Emirates Department of Gastroenterology Valiant ClinicDubaiUnited Arab Emirates Department of Gastroenterology and Endoscopy American HospitalDubaiUnited Arab Emirates Gastroenterology and Endoscopy Unit Al Zahra HospitalDubaiUnited Arab Emirates Gastroenterology Division Sheikh Khalifa Medical CityAbu DhabiUnited Arab Emirates Digestive Disease Unit Rashid HospitalDubaiUnited Arab Emirates Digestive Disease Institute Cleveland ClinicAbu DhabiUnited Arab Emirates Department of Gastroenterology Mediclinic City HospitalDubaiUnited Arab Emirates Gastroenterology and Hepatology Tawam HospitalAl AinUnited Arab Emirates Department of Gastroenterology The Pennine Acute Hospitals NHS TrustManchester Academic Health SciencesUniversity of ManchesterManchester M85RBUnited Kingdom

Ulcerative colitis and Crohn’s disease are the main entities of inflammatory bowel disease characterized by chronic remittent inflammation of the gastrointestinal *** incidence and prevalence are on the rise worldwide,and the heterogeneity between patients and within individuals over time is *** progressive advance in our understanding of the etiopathogenesis coupled with an unprecedented increase in therapeutic options have changed the management towards evidence-based interventions by clinicians with *** guideline was stimulated and supported by the Emirates Gastroenterology and Hepatology Society following a systematic review and a Delphi consensus process that provided evidence-and expert opinion-based *** up-to-date guidance is provided regarding diagnosis,evaluation of disease severity,appropriate and timely use of different investigations,choice of appropriate therapy for induction and remission phase according to disease severity,and management of main complications.

关键词： Ulcerative colitis Crohn’s disease Infliximab Adalimumab Vedolizumab Ustekinumab Tofacitinib

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