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Comparison of.purif.cation processes of.natural gas obtained f.om three dif.erent regions in the world

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Journal of.Natural Gas Chemistry 2012年第1期21卷 61-68页

作者： Tansel Koyun Mehmet Kunduz Hakan f. Oztop ibrahim Ucgul Department of.Mechanical engineering Suleyman Demirel University Department of.Mechanical engineering Technology Faculty Fιrat University Deparment of.Mechanical engineering College of Engineering King Saud University Department of.Textile engineering Suleyman Demirel University

Natural gases obtained f.om dif.erent regions in the world as Scholen-Germany, Saudi Arabia and Iran were purif.ed with a package code and the obtained results were compared in this study. f.r purif.cation process, both natural gases f.owing in a vertical pipe and monoethanolamine （MEA） f.owing as a f.lm f.om the internal surf.ce of.a pipe were examined together. Both f.uids were f.own in a vertical and laminar regime. Binary dif.usion coef.icients, Schmidt numbers （Sc） and dynamical viscosities were calculated individually f.r three types of.natural gases. It is demonstrated that the chemical absorption method by MEA process is the most appropriate method at high DamkOhler （Da） numbers particularly f.r natural gases containing high concentrations of.CO2 and H2S.

关键词： natural gas purif.cation monoethanolamine (MEA)

Ef.ects of.body mass index on intraocular pressure and ocular pulse amplitude

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International Journal of.Ophthalmology(english edition) 2012年第5期5卷 605-608页

作者： Remzi Karadag Zeynel Arslanyilmaz Bahri Aydin ibrahim f. hep.en Department of.Ophthalmology Istanbul Medeniyet University Medical SchoolIstanbul Turkey Department of.Ophthalmology Fatih University Medical SchoolAnkara Turkey

AIM: To investigate the ef.ects of.body mass index (BMI) on intraocular pressure (IOP) and ocular pulse amplitude(OPA). METHODS: Totally 140 healthy individuals without any systemic diseases were included in the study. BMI (kg/m2) was calculated f.r every individual. IOP and OPA were measured with Pascal Dynamic contour tonometer (DCT). Blood pressure was also measured along with the DCT. The patients were divided into three groups according to BMI as: Group1, BMIf.IOP, OPA, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were used in statistical ***: In Group1, the means of.IOP, OPA, were 16.8±2.3mmHg, 2.7±0.7mmHg respectively; and SBP, DBP were 120.0±6.1mmHg, and 77.4±5.6mmHg respectively. In group2, the mean IOP, OPA, SBP, and DBP were f.und to be 16.6±2.1mmHg, 2.4±0.7mmHg, 121.7±5.3mmHg, and 79.5±4.9mmHg respectively. In group3, the mean IOP, OPA, SBP, and DBP were f.und to be 17.3±1.7mmHg, 2.1±0.7mmHg, 122.4±5.7mmHg, and 79.7±5.2mmHg respectively. There were no statistically signif.cant dif.erence between groups in terms of.IOP, SBP and DBP, while OPA values were signif.cantly lower in group3 (P=0.001). CONCLUSION: Decreased OPA values in individuals with higher BMI may indicate that subjects with higher BMI have lower choroidal perf.sion and lower ocular blood f.ow.

关键词： body mass index choroidal perf.sion intraocular pressure ocular pulse amplitude obesity

Synthesis of.some new f.sed coumarin derivatives

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Chinese Journal of.Chemistry 2000年第4期18卷 590-595页

作者： EL-DEen ibrahim Mohey ibrahim H.K. MAHMOUD f.f. f.culty of.Education Suez Canal University Port-Said EgyptFaculty of Science Suez Canal University Ismailia EgyptFaculty of Science (for Girls) Al-Azhar University Nasr City Egypt

2-Hydrazino-4-hydroxy-5H-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (3) was prepared via condensation of.2 with hydrazine hydrate. Treatment of.3 with methylene chloride, ethyl chlorof.rmate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 - ( substituted ) hydrazino - 4 -hydro-xy-5H-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (4, 5, 6, and 10), f.llowed by cyclization of.4, 5 and 6 with dimethyl f.rmamide and f.sed sodium acetate under ref.ux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β-(toloyl) acrylic acid, ethyl α-cyano-p-methoxycinnamate, diethyl malonate and acetyl chloride af.ording the corresponding 2-(substituted) hydrazino-4-hydroxy-5H-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).

关键词： Synthesis f.sed coumarin derivatives cyclization

Inf.uence of.chemical reaction on heat and mass transf.r of.non-Newtonian f.uid with yield stress by f.ee convection f.om vertical surf.ce in porous medium considering Soret ef.ect

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Applied Mathematics and Mechanics(english Edition) 2010年第6期31卷 675-684页

作者： f. S. ibrahim f. M. HADY S. M. ABDEL-GAIED M. R. EID Department of.Mathematics Faculty of Science Assiut University Department of.Science and Mathematics Faculty of Education Assiut University

The ef.ect of.chemical reaction on f.ee convection heat and mass transf.r f.r a non-Newtonian power law f.uid over a vertical f.at plate embedded in a f.uid-saturated porous medium has been studied in the presence of.the yield stress and the Soret ef.ect. The governing boundary layer equations and boundary conditions are cast into a dimen- sionless f.rm by similarity transf.rmations, and the resulting system of.equations is solved by a f.nite dif.erence method. The results are preSented and discussed f.r concentration prof.les, as well as the Nusselt number and the Sherwood number f.r various values of.the parameters, which govern the problem. The results obtained show that the f.ow f.eld is inf.uenced appreciably by the presence of.the chemical reaction parameter γ the order *** chemical reaction parameter m, the Soret number St, the buoyancy ratio N, the Lewis number Le, and the dimensionless rheological parameter Ω.

关键词： non-Newtonian f.uid f.ee convection chemical reaction yield stress Soret ef.ect

Determination of.gamma-ray parameters f.r polyethylene glycol of.dif.erent molecular weights

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Nuclear Science and Techniques 2017年第11期28卷 180-187页

作者： ibrahim f. Al-Hamarneh Mohammad W. Marashdeh f.had I. Almasoud Ahmad Alkaoud Department of.Physics Faculty of Science Al-Balqa Applied University Al-Salt 19117 Jordan Department of.Physics College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU)Riyadh 11623 Saudi Arabia Nuclear Science Research Institute King Abdulaziz City for Science and Technology (KACST) Riyadh 11442 Saudi Arabia National Centre f.r Nuclear Technology (NCNT) King Abdulaziz City for Science and Technology (KACST)Riyadh 11442 Saudi Arabia

Mass attenuation coef.icient(μ_m) f.r polyethylene glycol(PEG) of.dif.erent molecular weights was determined by using NaI(Tl) scintillator and Win Xcom mixture rule at gamma energies of.59.5, 302.9, 356.0, 661.7, 1173.2 and 1332.5 keV. The total atomic, molecular and electronic cross sections, half.value layer, ef.ective atomic and electron numbers, mass energy-absorption coef.icients and kerma relative to air are calculated. The energy and compositional dependence of.μ_m values, and the related radiation absorption parameters, are evaluated and discussed. The experimental results agree well with the theoretical ones, within an uncertainty of.1% in the ef.ective atomic number f.r all PEG samples at the designated energies.

关键词： Polyethylene glycol Mass attenuation coef.icient Ef.ective atomic number Electron density Kerma relative to air

Cyclization of.4,5-Diamino Pyrazole Derivatives and Their Antibacterial Activities

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Chinese Journal of.Chemistry 2011年第7期29卷 1451-1459页

作者： Rizk, Hala f. EI-Badawi, Mahmoud A. ibrahim, Seham A. EI-Borai, Mohamed A. Department of.Chemistry Faculty of Science Tanta University Tanta Egypt

A convenient synthesis of.intermediate 4,5-diamino-3-aryl-l-phenylpyrazoles 4a--4c was reported. The dif.erent cyclization reactions were carried out with chalcone, 2-mercaptoacetic acid and p-anisialdehyde, ethyl chlorof.rmate, glyoxal and thiourea to af.ord dif.erent N and S containing heterocycles. The reaction conditions were compared by conventional heating and microwave irradiation. The structures of.the cyclization products were de- termined by analytical and spectroscopic data. All the synthesized compounds were screened f.r antibacterial activities in vitro.

关键词： 4,5-diaminopyrazole cyclization f.sed heterocyclic ring systems microwave chemistry antibacterial activities

COVID19 Outbreak:A Hierarchical f.amework f.r User Sentiment Analysis

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Computers, Materials & Continua 2022年第2期70卷 2507-2524页

作者： Ahmed f.ibrahim M.Hassaballah Abdelmgeid A.Ali Yunyoung Nam ibrahim A.ibrahim Department of.Computer Science Faculty of Computer ScienceNahda UniversityBanisuefEgypt Department of.Computer Science Faculty of Computers and InformationSouth Valley UniversityQenaEgypt f.culty of.Computers and Inf.rmation Minia UniversityAlMiniaEgypt Department of.Computer Science and engineering Soonchunhyang UniversityAsanKorea

Social networking sites in the most modernized world are f.ooded with large data *** the sentiment polarity of.important aspects is necessary;as it helps to determine people’s opinions through what they *** Coronavirus pandemic has invaded the world and been given a mention in the social media on a large *** a very short period of.time,tweets indicate unpredicted increase of.*** ref.ect people’s opinions and thoughts with regard to coronavirus and its impact on *** research community has been interested in discovering the hidden relationships f.om short texts such as Twitter and Weiboa;due to their shortness and *** this paper,a hierarchical twitter sentiment model(HTSM)is proposed to show people’s opinions in short *** proposed HTSM has two main f.atures as f.llows:constructing a hierarchical tree of.important aspects f.om short texts without a predef.ned hierarchy depth and width,as well as analyzing the extracted opinions to discover the sentiment polarity on those important aspects by applying a valence aware dictionary f.r sentiment reasoner(VADER)sentiment *** tweets f.r each extracted important aspect can be categorized as f.llows:strongly positive,positive,neutral,strongly negative,or *** quality of.the proposed model is validated by applying it to a popular product and a widespread *** results show that the proposed model outperf.rms the state-of.the-art methods used in analyzing people’s opinions in short text ef.ectively.

关键词： COVID19 COVID data sentiment analysis hierarchical clustering sentiment tree

Boundary-layer non-Newtonian f.ow over vertical plate in porous medium saturated with nanof.uid

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Applied Mathematics and Mechanics(english Edition) 2011年第12期32卷 1577-1586页

作者： f.M. HADY f. S. ibrahim S. M. ABDEL-GAIED M. R. EID Department of.Mathematics Faculty of Science Assiut University Assiut 71516 Egypt Department of.Science and Mathematics Faculty of Education Assiut University The New Valley 72111 Egypt

The f.ee convective heat transf.r to the power-law non-Newtonian f.ow f.om a vertical plate in a porous medium saturated with nanof.uid under laminar conditions is investigated. It is considered that the non-Newtonian nanof.uid obeys the mathematical model of.power-law. The model used f.r the nanof.uid incorporates the ef.ects of.Brown- ian motion and thermophoresis. The partial dif.erential system governing the problem is transf.rmed into an ordinary system via a usual similarity transf.rmation. The numer- ical solutions of.the resulting ordinary system are obtained. These solutions depend on the power-law index n, Lewis number Le, buoyancy-ratio number Nr, Brownian motion number Nb, and thermophoresis number Nt. f.r various values of.n and Le, the ef.ects of.the inf.uence parameters on the f.uid behavior as well as the reduced Nusselt number are presented and discussed.

关键词： non-Newtonian f.ee convection nanof.uid porous media

An Expansion Theorem f.r an Eigenvalue Problem of.an Arbitrary Multiply Connected Domain with an Eigenparameter in a General Type of.Boundary Conditions

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Acta Mathematica Sinica,english Series 1995年第4期11卷 399-407页

作者： E. M. E. Zayed S. f. M. ibrahim Mathematics Department f.culty of.Science Zagazig University Zagazig Egypt Mathematics Department f.culty of.Science Ain Shams University Heliopolis Cairo Egypt

The object of.this paper is to establish an expansion theorem f.r a regular right- def.nite eigenvalue problem with an eigenvalue parameter λ which is contained in the Schrodinger partial dif.erential,equation and in a general type of.boundary conditions on the boundary of.an arbitrary multiply connected bounded domain in R^n(n≥2).We associate with this problem an essentially self.adjoint operator in a suitably def.ned Hilbert space and then we develop an associated eigenf.nction expansion theorem.

关键词： Eigenvalue problem Multiply connected domain Eigenf.nction expansion