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Preservability of rabbit semen after chilled storage in tris based extender enriched with different concentrations of Propolis ethanolic extract (PEE)

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Asian pacific Journal of Reproduction 2017年第2期6卷 68-76页

作者： Islam El-Sayed El-Seadawy Walid said El-Nattat Magda Mohamed El-Tohamy Samy Ali hussein Aziza Yakot Abdelfattah El-Senosy ahmed said hussein Animal Reproduction and A I Dept.Veterinary Research DivisionNational Research CentreGizaEgypt Biochemistry and Clinical Biochemistry Dept. Faculty of Veterinary MedicineBenha UniversityEgypt Food Industry Dept Food Industry and Nutrition Research DivisionNational Research CenterGizaEgypt

Objective:To maintain semen quality of male rabbits during chilled storage by enrichment the tris based diluent with different concentrations of propolis ethanolic ***: Total phenolic and total flavonoid contents, as well as antioxidant activity was determined in propolis ethanolic extract (PEE). The extract was analysed by HPLC for separation and identification of target metabolites. Semen was collected from 10 rabbit bucks, pooled, then divided into five aliquots (each of 500 μL) and diluted each in 5 mL Tris-citric acid-glucose-egg yolk extender (TCGY). The 1st aliquot served as control while PEE was added at concentration of 0.8, 1.2, 1.6 and 2.0 mg/5 mL tris extender in the aliquot 2, 3, 4 and 5 respectively. Diluted semen samples were subjected to cooling at 4℃ for 72 h. Sperm motility, sperm viability, sperm abnormality, sperm membrane integrity and acrosome integrity were evaluated in chilled semen allover the chilling ***:The resluts revealed presence of a considerable amount of total phenolic compounds (98.67 mg GAE/g extract) and total flavonoids (70.16 mg CE/g extract) which were parallel to an antioxidant activity assessed as ABTS, DPPH and FRAP (198.65, 180.18 and 306.17 mM TE/g extract respectively). The dominant phenolic acid was chlorogenic acids (3.959 mg/g extract). Other compounds were found in less amounts rosmarinic acid (3.959 mg/g extract), myrcetin (1.946 mg/g extract), kaempferol (1.089 mg/g extract) and apeginin-7-glucoside (1.113 mg/g extract). Obtained results clearly demonstrated that the addition of (1.2-1.6) mg PEE in the chilled extended rabbit semen proved to be beneficial for maintaining semen characteristics compared to control and the addition of 0.8 and 2 mg ***: The enrichment of rabbit semen tris-basic extender with (1.2-1.6) mg PEE/5 mL tris-extender (as the best and safe concentrations) maintain the sperm characteristics in good condition all over 72 h of chilling.

关键词： Male rabbits Semen extender Propolis extract Antioxidants HPLC

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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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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

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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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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

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Crystal lattice free volume and thermal decomposition of nitramines

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Defence Technology（防务技术） 2019年第1期15卷 51-57页

作者： Svatopluk Zeman Ning Liu ahmed K.hussein Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of Pardubice Xi’an Modern Chemistry Research Institute

The linear, directly proportional, equations between the Arrhenius parameters(E_α, and log A) of the thermal decomposition and the crystal lattice free space per molecule, △V, of 22 nitramines are described. It is shown that, because of a significant limitation by the molecular structural characteristics of such compounds, they are divided into a number of partial relationships. These partial relationships divide the nitramines into a group of substances relating to dimethyl nitramine and a sub-group related to e-HNIW. These directly proportional equations mean that an increase in the △Vvalues is related to an increase in the thermal stability of the corresponding nitramines. A comparison with similar published dependencies for the impact and friction sensitivities, on the one hand, and with the relationship between the E_a values and the sum of the negative and positive extremes of molecular surface electrostatic potentials, on the other, confirms the well-known fact that intermolecular interaction in the nitramines studied plays a decisive role in the thermal reactivity of such compounds. The crystal lattice free space manifests itself here perhaps only in the solid state thermal decomposition of RDX, HMX and DINGU. This study again confirms a level of disorder in the distribution of the forces in the crystal lattice of the"common" quality of e-HNIW,compared with its "reduced sensitivity(RS)" or pure analogues.

关键词： Crystal lattice Thermal decomposition Initiation reactivity Nitramines

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Design, Sonosynthesis, Quantum-Chemical Calculations, and Evaluation of New Mono-and Bis-pyridine Dicarbonitriles as Antiproliferative Agents

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Chinese Journal of Chemistry 2020年第5期38卷 501-508页

作者： Wael Abdelgayd ahmed Arafa Modather F.hussein Chemistry Department College of ScienceJouf UniversityP.O.Box 2014SakakaAljoufKingdom of Saudi Arabia Chemistry Department Faculty of ScienceFayoum UniversityP.O.Box 63514Fayoum CityEgypt Chemistry Department Faculty of ScienceAl-Azhar UniversityAsyut branchEgypt

A highly efficient,simple,and clean single-step sonosynthetic procedure has been sophisticated for assembling new series of mono-and bis-pyridine dicarbonitriles from ketones,HCl,and *** presented protocol is applicable for the preparation of a broad range of uniquely substituted pyridine dicarbonitriles and seems to be superior in comparison with other previously reported *** antiproliferative impact of the newly synthesized derivatives was screened towards three representative cancer cell lines(MCF-7,A549,and HCT116).Most of the evaluated derivatives showed a moderate to excellent anti-proliferative activity towards the selected cell *** these,compounds 4h,4k,10,12a,and 12b showed both potent anticancer activity(ICs058μM)on non-tumorigenic cells(MCF-10A and NCM460),suggesting their promising potential to be lead molecules for future antitumor drug *** structure-activity relationships have been also ***,quantum chemical studies based on Density Functional Theory(DFT)of the synthesized compounds were investigated and found to be consistent with the in vitro inhibitory activities.

关键词： pyridine nitrile synthesis

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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

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Plant Leaf Diseases Classification Using Improved K-Means Clustering and SVM Algorithm for Segmentation

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Computers, Materials & Continua 2023年第7期76卷 367-382页

作者： Mona Jamjoom ahmed Elhadad hussein Abulkasim Safia Abbas Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia Department of Computer Science Faculty of Computers and InformationSouth Valley UniversityQena83523Egypt Faculty of Science New Valley UniversityEl-Kharga72511Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt

Several pests feed on leaves,stems,bases,and the entire plant,causing plant *** a result,it is vital to identify and eliminate the disease before causing any damage to *** detecting plant disease and treating it is pretty challenging in this *** processing is employed to detect plant disease since it requires much effort and an extended processing *** main goal of this study is to discover the disease that affects the plants by creating an image processing system that can recognize and classify four different forms of plant diseases,including Phytophthora infestans,Fusarium graminearum,Puccinia graminis,tomato yellow leaf ***,this work uses the Support vector machine(SVM)classifier to detect and classify the plant disease using various steps like image acquisition,Pre-processing,Segmentation,feature extraction,and *** gray level co-occurrence matrix(GLCM)and the local binary pattern features(LBP)are used to identify the disease-affected portion of the plant *** to experimental data,the proposed technology can correctly detect and diagnose plant sickness with a 97.2 percent accuracy.

关键词： SVM machine learning GLCM algorithm K-means clustering LBP

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Double-antibody-based nano-biosensing systemfor the onsite monitoring of SARS-CoV-2 variants

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Microsystems & Nanoengineering 2023年第4期9卷 247-262页

作者： Heba A.hussein ahmed Kandeil Mokhtar Gomaa Rabeay Y.A.Hassan Virology Department Animal Health Research Institute(AHRI)Agricultural Research Center(ARC)Giza 12619Egypt Biosensors Research Laboratory Zewail City of Science and Technology6th October CityGiza 12578Egypt Center of Scientific Excellence for Influenza Viruses Environmental Research DivisionNational Research CentreGiza 12622Egypt Nanoscience Program University of Science and Technology(UST)Zewail City of Science and TechnologyGiza 12578Egypt

The fast and reliable diagnosis of COVID-19 is the foremost priority for promoting public health ***, double-antibody-based immunobiosensor chips were designed, constructed, and exploited for clinicaldiagnosis. Gold nanoparticles/tungsten oxide/carbon nanotubes (AuNPs/WO3/CNTs) were used as the active workingsensor surface to support the chemical immobilization of a mixture of SARS-CoV-2 antibodies (anti-RBD-S and anti-RBD-S-anti-Llama monoclonal antibodies). The morphology and chemical functionalization of the fabricateddisposable immunochips was characterized using scanning electron microscopy (SEM), Fourier transform infrared(FTIR) spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). After full assayoptimization, the immunobiosensor showed a high sensitivity to detect SARS-CoV-2-S protein with limits of detectionand quantification of 1.8 and 5.6 pg/mL, respectively. On the other hand, for the SARS-CoV-2 whole virus particleanalysis, the detection and quantification limits were determined to be 5.7 and 17 pg/mL, respectively. The biosensorshowed a highly selective response toward SARS-CoV-2, even in the presence of influenza, nontargeting humancoronaviruses, and Middle East respiratory syndrome coronavirus (MERS-CoV). The immunochips exhibited distinctresponses toward the variants of concern: B.1>C.36.3>Omicron> Delta> Alpha coronavirus variants. For biosensorvalidation, twenty-nine clinical specimens were analyzed, and the impedimetric responses were positively detected fortwo Delta samples, eighteen Omicron samples, and six B.1-type samples in addition to three negative ***, the immunobiosensor was fabricated in the form of ready-to-use chips capable of sensitive detection ofvirus variants, especially variants of concern (VOC) and interest, in a specimen within 15 min. The chips providedinstantaneous detection with the direct application of clinical samples and are considered a point-of-care

关键词： system limits optimization

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