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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 collected.Fillers 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 2,4,6-trinitrotoluene.For 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 initiation.Similarly,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 BCHMX.Specific rate constants from Vacuum Stability Test(VST)of four nitramines and twenty PBXs are introduced into relationships with their enthalpies of formation.Regarding to all the mentioned cases,increasing of energy content of the studied explosives leads to increase of the relative explosive strength or initiation reactivity,respectively.Exception 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 azide.Admixture 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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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 tetracyanoethylene.The 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 methods.The 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 lines.Of 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 discovery.The structure-activity relationships have been also discussed.Moreover,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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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 values.However,more realistic dependencies for the TMD and D values are obtained by using correlations with ratio of the intrinsic molecular volume,Vint,to△V(i.e.Vint/△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 other.It 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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Epidemiology of Measles Cases in South Darfur State, Sudan, 2011-2015

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Biomedical and Environmental Sciences 2017年第12期30卷 917-921页

作者： TAHA hussein Musa REHAB Ibrahim Kambo ABDELKAREEM Abdallah ahmed HASSAN hussein Musa Key Laboratory of Environmental Medicine Engineering Ministry of Education Department of Epidemioiogy and Biostatistics School of Public Health Southeast University Nanjing 210009 Jiangsu China World Health Organization WHO South Darfur Sub-Office Nyala 999129 Sudan Department of Physiology and Biochemistry Faculty of Veterinary Sciences University of Nyala P.O Box 155 999129 Sudan Department of Medical Microbiology Faculty of Medical Laboratory Sciences University of Khartoum Khartoum state P.O. Box 11081 Khartoum 999219 Sudan

Case-based surveillance measles data was defined according to World Health Organization （WHO） guidelines. A total of 511 measles cases were studied from 2011 to 2015 in Southern Darfur State, Sudan and 58.1% of cases were confirmed from Nyala city. About 43.4% of cases were males, 56.6% of cases were female, and 47.7% were children under five years old. Similarity, within February to June, the cases increased by 8.0% in children vaccinated through measles campaign, and 5.3% in children that used child vaccination card and 78.7% in unvaccinated one.

关键词： Epidemiology of Measles Cases South Darfur State

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Cronkhite-Canada syndrome:First case report from Egypt and North Africa

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World Journal of Gastrointestinal Endoscopy 2022年第10期14卷 642-647页

作者： ahmed Elsayed Alzamzamy Ashraf Aboubakr hussein H Okasha Abeer Abdellatef Shaimaa Elkholy Mahmoudd Wahba Mohamed Alboraie hussein Elsayed Mohamed O Othman Department of Gastroenterology and Hepatology Maadi Armed Forces Medical ComplexMilitary Medical AcademyCairo 11711Egypt Department of Internal Medicine Division of GastroenterologyHepatology and EndoscopyCairo UniversityCairo 11311Egypt Department of Internal Medicine Al-Azhar UniversityCairo 11311Egypt Department of Pathology Military Medical AcademyCairo 11711Egypt Department of Internal Medicine Baylor College of MedicineHoustonTX 77082United States

BACKGROUND Gastrointestinal(GI)polyposis is a rare condition in GI diseases.To date about 500 cases of Cronkhite-Canada syndrome(CCS)have been reported worldwide.CASE SUMMARY We report a 60-year-old female patient who presented with dyspepsia,abdominal pain,and weight loss of 1-year duration.Her physical examination showed alopecia and onychodystrophy.Upper endoscopy revealed diffuse markedly thickened gastric mucosa involving the whole stomach with thickened gastric rugae and numerous polypoidal lesions.Histopathological examination showed marked hyperplasia of the foveolar glands with inflammatory cell infiltration.Endoscopic ultrasound showed a significantly hypertrophic mucosa and muscularis mucosa,while the submucosa and the muscularis propria were spared,favouring its benign nature.Colonoscopy showed multiple sessile polyps scattered at different parts of the colon.Histopathological examination revealed tubular adenomatous polyps with low-grade dysplasia.Differential diagnoses included CCS,Menterier disease(MD),other polyposis syndromes,lymphoma,amyloidosis,and gastric malignancies.The presence of alopecia,nail dystrophy,GI polyposis,markedly thickened gastric mucosa and folds,abdominal pain,weight loss,and marked foveolar gland hyperplasia;all was in favour of CCS.Lymphoma was excluded due to sparing of the muscularis propria.The presence of colonic polyps and antral and duodenal infiltration,and the absence of hypoproteinaemia decreased the possibility for MD.CONCLUSION The patient was diagnosed as having CCS.

关键词： Gastrointestinal polyposis Thickened gastric mucosa Cronkhite-Canada syndrome Case report

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Association of anxiety- depressive disorders with irritable bowel syndrome among patients attending a rural family practice center: a comparative cross- sectional study

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General Psychiatry 2021年第6期34卷 16-23页

作者： Alaa Adel Mohammed Heba ahmed moustafa Hebatallah Nour-Eldein Rabab Atta Saudi Family Medicine Department Suez Canal UniversityIsmailiaEgypt

Background Comorbidity of irritable bowel syndrome(IBS)and psychiatric disorders is common,and the prevalence of at least one psychiatric disorder has been reported as high as 80%among patients with IBS.Aims To explore the association of anxiety-depressive disorders with IBS and its different subtypes,and to evaluate the associations of lifestyle habits,dietary habits and sleeping quality with IBS.Methods A comparative cross-sectional study was conducted at the AL-Mahsama Family Practice Center,Ismailia,Egypt.It was carried out between October 2019 and October 2020.Participants were categorised into 175 patients with IBS,diagnosed using the Rome IV criteria,and 175 patients without IBS.A semistructured questionnaire was used to collect data on sociodemographic characteristics,lifestyle habits,dietary habits and sleep quality from both groups.The Hamilton Anxiety Rating Scale was used to assess anxiety symptoms,whereas the Beck Depression Inventory Second Edition was used to assess depression symptoms.Results There was a high statistically significant difference between both groups with regard to age,education,occupation and socioeconomic status(SES),being a smoker,being physically inactive,having sleep disturbance and having irregular meals;being either obese or overweight was more reported in the IBS group.There was a high statistically significant difference in the rate of anxiety and depression between patients with and without IBS.Mild,moderate and severe anxiety were reported in 37.1%,42.9%and 20.0%of patients with IBS while most(80.0%)of the patients without IBS reported mild anxiety.Regarding depression,mild,moderate and severe depression were reported in 60.0%,14.3%and 25.7%of the patients with IBS while most(82.9%)of the non-IBS participants reported mild depression.Conclusions The study shows a significant association between anxiety-depressive disorders and IBS,but no significant associations between anxiety-depressive disorders and IBS subtypes.

关键词： patients disorders sectional

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Microbiological Quality of Freshly Prepared, Packaged Fruit and Milk Juices Sold in Cafés, Shops, and Supermarkets in Hargeisa, Somaliland

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Advances in Microbiology 2023年第5期13卷 212-222页

作者： Mohamud ahmed Farah ahmed hussein Esa Helmi S. Abdelaziz Department of Health Science Faculty of Medicine and Health Science Abaarso Tech University Hargeisa Somaliland College of Applied Science University of Hargeisa Hargeisa Somaliland Hargeisa Water Quality Control Laboratory Hargeisa Water Agency Hargeisa Somaliland Department of Microbiology Faculty of Medical Laboratory Science Haldoor Medical University Hargeisa Somaliland

Background: Due to their delicious taste, high nutritional content, and health benefits, fruit juices are well-known drinks in many countries and are now an essential component of the modern diet. Objective: Determining the microbiological quality of both packaged and freshly made fruit and milk juices. Method: The spread-plate approach was employed to isolate and count the bacteria. 90 ml of sterile peptone water were blended with 10 ml of well-mixed, packed, and freshly made fruit juices. The samples were sequentially diluted (101 - 105) in accordance with the Indian Manual of Food Microbiological Testing Methods. Results: From eight samples of imported packaged fruit and milk juice, the average of total coliform, staphylococci, and viable bacterial counts were zero, 1.39 × 102, and 2 × 102 CFU/ml, respectively. In contrast, from three samples of locally produced fruit and milk juice, the average of total coliform, staphylococci, and viable bacterial counts were zero, 5.83 × 102, and 2.73 × 103 CFU/ml, respectively. Four samples of handmade prepared fruit and milk juices had a mean of total coliform, staphylococci, and viable bacterial count of 1.441 × 104, 4.1 × 103, and 2.35 × 105 CFU/ml, respectively. Conclusion: 33.3% of the results from microbiological analysis of freshly made fruit and milk juices met the permissible range of the Revised Microbiological Standards for Fruit and Vegetables and Their Products, which were published in 2018 and as well as the Hong Kong Center for Food Safety, whereas 66.7% of the microbiological analyses of freshly prepared fruit and milk juices were above the permissible reference range of GSO standard 2000. 12.5% of the investigated imported and packed fruits and milk juices had one failed test (TSC), which was above the acceptable limit, 87.5% of the tested samples of fruit and milk juices fulfilled the necessary standards of TCC, TVBC, and TSC. 100% of the tested locally manufactured fruit and milk juices complied with TSC, TCC, and TVBC requirements. All investigations sh

关键词： Total Viable Bacterial Count (TVBC) Total Coliform Count (TCC) Total Staphylococci Count (TSC) Colony Forming Unit (CFU) Gulf State Organization (GSO) Food and Drug Agent (FDA)

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Gd掺杂BiVO4高效制备及光催化去除有机物性能研究

Gd掺杂BiVO4高效制备及光催化去除有机物性能研究

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作者： hussein Abdelraouf Mohamed ahmed hussein 哈尔滨工业大学

学位级别：硕士

药品和个人护理产品(PPCPs)是一类新兴的有机污染物(EOC),包含各类抗生素、激素和人工合成麝香等。近些年,PPCPs在生活污水和工业废水中被广泛检出,如果不经过处理,将通过江河湖泊,在食物链中层层富集,最终影响人类健康。大多数PPCPs结... 详细信息

药品和个人护理产品(PPCPs)是一类新兴的有机污染物(EOC),包含各类抗生素、激素和人工合成麝香等。近些年,PPCPs在生活污水和工业废水中被广泛检出,如果不经过处理,将通过江河湖泊,在食物链中层层富集,最终影响人类健康。大多数PPCPs结构稳定,自然条件下难以降解,常规水处理技术难以将其有效去除。光催化技术是一种将太阳能转化为化学能的工艺,具有环保、可持续和低成本的优点,因此被广泛应用于PPCPs类污染物的降解。铋基光催化剂(BiVO)具有窄带隙、n型结构、可见光响应、无毒、成本低、稳定性好等优点,可作为光催化剂降解PPCPs。为提高BiVO电子空穴的分离效率,本研究采用金属和非金属掺杂。此外,为了节省制备过程中的功耗,使用快速合成方法在低于100℃条件下制备不同的光催化剂,以降解各种PPCPs。与水热合成法(HSM)和微波水热合成法(MHSM)相比,快速合成方法在低于100℃(STSM)对氧氟沙星(OFL)的降解表现出优越性,STSM、HSM和MHSM制备的BiVO对OFL的去除率分别为0.02855、0.02151和0.01422 min。研究还表明,制备条件的p H值为7时,Gd掺杂比其他金属掺杂更有优势,Br掺杂相对于S掺杂更有优势。利用紫外-可见漫反射光谱(DRS)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、光致发光光谱(PL)和比表面积分析(BET)对光催化剂进行表征,分析改性前后光催化剂的特性。Gd掺杂使BiVO具有四方相结构,而Br的掺杂对BiVO的单斜相结构没有影响。采用快速合成方法在低于100℃条件下合成原始和改性BiVO光催化剂,结果表明,快速合成的材料在Gd掺杂后显著增加了原始BiVO光催化剂材料的比表面积。同时,Br的掺杂对BiVO的吸收边和禁带宽度影响较小,而Gd的掺杂对吸收边和禁带宽度有较大影响。此外,Gd掺杂影响了BiVO的粒径,使其粒径变小,有助于提高其吸附和光催化活性,而Br对原始BiVO的粒径几乎没有影响。在太阳光条件下,5%、7%和10%的Gd掺杂BiVO对OFL的去除速率常数分别是未改性BiVO的1.53、1.61和1.83倍。暗反应40 min,光照1 h后,5%Gd-BiVO对双氯芬酸、盐酸四环素、氧氟沙星、罗丹明B和磺胺嘧啶(10 mg/L)的降解率分别达到98.63±0.08%、98.07±0.49%、97.98±2.02%、92.09±0.36%和78.56±0.38%。在酸性条件下,Gd掺杂的光催化剂具有较好的光催化性能,SO和HPO显著抑制了OFL的降解,这是由于SO和HPO离子对h和OH的捕获。5%Gd-BiVO在循环使用5次后也表现出较好的降解性能,具有良好的可重复利用性。研究发现,在BiVO、Br-BiVO和Gd-BiVO体系中,光生空穴h和O是主要的活性物种,而OH在整个体系中的作用较小。根据淬灭实验和ESR实验结果,提出了BiVO和Gd-BiVO体系的降解机制。本研究通过较简单方法制备的Gd掺杂BiVO光催化剂,提升了光生电子空穴的分离效率,在模拟太阳光照射下,实现了高效降解PPCPs和染料类污染物。

关键词： Gd-BiVO4 太阳光 OFL 降解机理高效制备

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