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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

cis-1,3,4,6-Tetranitrooctahydroimidazo-[4,5-d]imidazole(BCHMX)as a part of explosive mixtures

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Defence Technology（防务技术） 2018年第5期14卷 380-384页

作者： Svatopluk Zeman ahmed k.hussein ahmed Elbeih Marcela Jungova Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCZ-532 10PardubiceCzech Republic Military Technical College Kobry ElkobbahCairoEgypt

cis-1,3,4,6-Tetranitrooctahydroimidazo-[4,5-d]imidazole(BCHMX) is a relatively available bicyclic nitramine in the present. Due to the high energetic content of its molecule(deformation of valence angles) it has heat of formation higher than β-1,3,5,7-tetranitro-1,3,5,7-tetrazocane(β-HMX) by nearly three times. As a result, it has heat of explosion and relative explosive strength exceed that of β-HMX including their corresponding PBXs. However, penetration abilities of PBXs based on HMX are higher than those based on BCHMX. The relatively high initiation reactivity of BCHMX could be modified in a wide range by its incorporation in a suitable polymeric matrices. Regarding to the performance, coating of BCHMX crystals by 5 wt% Viton A produces the maximum performance while the mixture of BCHMX with polydimethylsiloxane(PDMS) seems to be the optimum composition for the development of PBX with low sensitivity.

关键词： BCHMX Initiation Sensitivity Explosive strength Penetration

Crystal lattice free volume in a study of initiation reactivity of nitramines:Friction sensitivity

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Defence Technology（防务技术） 2018年第2期14卷 132-136页

作者： Svatopluk Zeman Ning Liu Marcela Jungová ahmed k.hussein Qi-long Yan Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCZ-532 10PardubiceCzech Republic Xi'an Modern Chemistry Research Institute Xi'anShaanxi710065China School of Astronautics Northwestern Polytechnical UniversityXi'an 710072ShaanxiChina

The relationship between friction sensitivity(FS) and the crystal lattice free space per molecule, △V. of thirteen nitramines is described by a linear equation, divided into a number of the partial relationships with strong limitations by their molecular structure characteristics. Increasing FS due to raising of the △V values is not clearly confirmed. The influence of the △V values on friction sensitivity of nitramines is similar to that of their aza atoms which influence the mutual orientations of nitro groups in neighboring molecules. The dipole-dipole interaction of the oxygen and nitrogen atoms of nitro groups in neighboring nitramine molecules has a major effect on their own FS. In accordance with this interaction, a directly proportional relationship was derived between FS and the intrinsic gas phase molecular volume, V_(int), of the nitramines mentioned, which is divided also into several straight lines according to relatively tight molecular structure similarity. The relationships found again confirm a level of disorder in the distribution of the forces in the crystal lattice of the "common" quality of ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, in comparison with its reduced sensitivity(RS) or chemically pure analogue.

关键词： Crystal lattice Friction Initiation reactivity Nitramines

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Relative Explosive Strength of Some Explosive Mixtures Containing Urea and/or Peroxides

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火炸药学报 2016年第5期39卷 22-27,34页

作者： ahmed k.hussein Svatopluk ZEMAN Muhamed SUCESkA Marcela JUNGOVA Institute of Energetic Materials Faculty of Chemical Technology University of Pardubice Czech Republic Brodarski Institute-Marine Research and Special Technologies ZagrebCroatia

Several mixtures,based on urea derivatives and some inorganic oxidants,including also alumina,were studied by means of ballistic mortar techniques with TNT as the reference *** detonation pressure(P),detonation velocity(D),detonation energy(Q),and volume of gaseous product at standard temperature and pressure(STP),V,were calculated using EXPLO5V6.3 thermochemical *** performance of the mixtures studied was discussed in relation to their thermal reactivity,determined by means of differential thermal analysis(DTA).It is shown that the presence of hydrogen peroxide in the form of its complex with urea(*** UHP)has a positive influence on the explosive strength of the corresponding mixtures which is linked to the hydroxy-radical formation in the mixtures during their initiation *** radicals might initiate(at least partially)powdered aluminum into oxidation in the CJ plane of the detonation *** containing UHP and magnesium are dangerous because of potential auto-ignition.

关键词： ballistic mortar TNT DTA peroxides perchlorates nitrates urea

Enhancing the explosive characteristics of a Semtex explosive by involving admixtures of BCHMX and HMX

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Defence Technology（防务技术） 2020年第2期16卷 487-492页

作者： ahmed Elbeih ahmed k.hussein Tamer Elshenawy Svatopluk Zeman Sara M.Hammad Ahmad Baraka Mohamed A.Elsayed Mohamed Gobara Hesham Tantawy Military Technical College Kobry ElkobbahCairoEgypt Technical Research Center CairoEgypt Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCzech Republic Faculty of Pharmacy University of CairoGizaEgypt

A well-known ternary plastic explosive,Czech Semtex 1H,contains a mixture of PETN and RDX softened by *** this work,BCHMX was used to replace PETN in Semtex 1H to form Sem-BC+*** addition,another mixture based on BCHMX and HMX as energetic fillers bonded by the polymeric matrix of Semtex 1H(Sem-BC+HMX)was *** particle size distribution of each individual explosive was determined to obtain the optimum mixing *** and impact sensitivities were *** velocity of detonation was reported practically and the detonation properties were calculated by EXPLO5 *** explosive strength of each sample was measured by the ballistic mortar *** conclusion confirms that the velocity of detonation of Sem-BC+HMX was the highest in comparison with the prepared ***-BC+RDX has the least impact and frictions ***-BC+RDX has higher detonation velocity,detonation properties and explosive strength than Semtex *** of BCHMX in Semtex 1H as a replacement for PETN is the candidate to produce a high performance advanced Czech plastic explosive.

关键词： Semtex Explosives Combustion Sensitivity Detonation Explosive strength

Efficient Computation Offloading of IoT-Based Workflows Using Discrete Teaching Learning-Based Optimization

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Computers, Materials & Continua 2022年第11期73卷 3685-3703页

作者： Mohamed k.hussein Mohamed H.Mousa Department of Computer Science Faculty of Computers and InformaticsSuez Canal UniversityIsmailiaEgypt Department of Information Technology College of Computer Science at AlKamilUniversity of JeddahJeddahSaudi Arabia

As the Internet of Things(IoT)and mobile devices have rapidly proliferated,their computationally intensive applications have developed into complex,concurrent IoT-based workflows involving multiple interdependent *** exploiting its low latency and high bandwidth,mobile edge computing(MEC)has emerged to achieve the high-performance computation offloading of these applications to satisfy the quality-of-service requirements of workflows and *** this study,we propose an offloading strategy for IoT-based workflows in a high-performance MEC *** proposed task-based offloading strategy consists of an optimization problem that includes task dependency,communication costs,workflow constraints,device energy consumption,and the heterogeneous characteristics of the edge *** addition,the optimal placement of workflow tasks is optimized using a discrete teaching learning-based optimization(DTLBO)*** experimental evaluations demonstrate that the proposed offloading strategy is effective at minimizing the energy consumption of mobile devices and reducing the execution times of workflows compared to offloading strategies using different metaheuristics,including particle swarm optimization and ant colony optimization.

关键词： High-performance computing internet of things(IoT) mobile edge computing(MEC) workflows computation offloading teaching learning-based optimization

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

The role of crystal lattice free volume in nitramine detonation

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Defence Technology（防务技术） 2019年第4期15卷 519-525页

作者： Svatopluk Zeman Ning Liu ahmed k. hussein Institute of Energetic Materials Faculty of Chemical Technology University of Pardubice CZ-532 10 Pardubice Czech Republic Xi'an Modern Chemistry Research Institute Xi'an Shaanxi 710065 China Military Technical College Kobry Elkobbah Cairo Egypt

Crystal lattice free volumes,△V,of 22 nitramines introduced into relationships of maximal theoretical crystal densities(TMD),detonation velocities(D)and volume heats of explosives(ρ.Q).Values of all these characteristics increase with an increase in the AV ***,more realistic dependencies for the TMD and D values are obtained by using correlations with ratio of the intrinsic molecular volume,Vint,to△V(***/△V),whereby the dependence on the D values reflects their similar relationship to a sum of the positive(VS,max)and negative(VS,min)extremes of the molecular surface electrostatic potentials(VS,∑).Also,directly proportional linear relationships are specified between the VS,∑ values on the one hand,and the △V and Vint/△V values,on the *** is stated that the crystal lattice free volumes might have a similar role in detonation of nitramines as the intermolecular force effect in their molecular crystals(they are as if representative of such forces).

关键词： Crystal lattice Detonation Initiation reactivity Nitramines

Fast adaptive regression-based model predictive control

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Control Theory and Technology 2023年第4期21卷 555-570页

作者： Eslam Mostafa hussein A.Aly ahmed Elliethy Electrical and Computer Engineering Military Technical CollegeCairo14627Egypt

Model predictive control(MPC)is an optimal control method that predicts the future states of the system being controlled and estimates the optimal control inputs that drive the predicted states to the required *** computations of the MPC are performed at pre-determined sample instances over a finite time *** number of sample instances and the horizon length determine the performance of the MPC and its computational cost.A long horizon with a large sample count allows the MPC to better estimate the inputs when the states have rapid changes over time,which results in better performance but at the expense of high computational ***,this long horizon is not always necessary,especially for slowly-varying *** this case,a short horizon with less sample count is preferable as the same MPC performance can be obtained but at a fraction of the computational *** this paper,we propose an adaptive regression-based MPC that predicts the best minimum horizon length and the sample count from several features extracted from the time-varying changes of the *** proposed technique builds a synthetic dataset using the system model and utilizes the dataset to train a support vector regressor that performs the *** proposed technique is experimentally compared with several state-of-the-art techniques on both linear and non-linear *** proposed technique shows a superior reduction in computational time with a reduction of about 35–65%compared with the other techniques without introducing a noticeable loss in performance.

关键词： Regression analysis MPC Control Parametrization Wavelet Support vector regression(SVR) Optimization