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Acta mechanica Sinica 2018年第3期34卷 507-514页

作者： z.m.zheng B.Wang School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Instimt Franco-Chinois de l'Energie Nucleaire Sun Yat-Sen UniversityZhuhai 519000China

Conventional heat transfer fluids usually have low thermal conductivity, limiting their efficiency in many applications. many experiments have shown that adding nanosize solid particles to conventional fluids can greatly enhance their thermal conductivity. To explain this anomalous phenomenon, many theoretical investigations have been conducted in recent years. Some of this research has indicated that the particle agglomeration effect that commonly occurs in nanofluids should play an important role in such enhancement of the thermal conductivity, while some have shown that the enhancement of the effective thermal conductivity might be accounted for by the structure of nanofluids, which can be described using the radial distribution function of particles. However, theoretical predictions from these studies are not in very good agreement with experimental results. This paper proposes a prediction model for the effective thermal conductivity of nanofluids, considering both the agglomeration effect and the radial distribution function of nanoparticles. The resulting theoretical predictions for several sets of nanofluids are highly consistent with experimental data.

关键词： Nanofluid Thermal conductivity modeling Agglomeration Radial distribution function

Predicting the response of continuous RC deep beams under varying levels of differential settlement

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 686-700页

作者： m.z.NASER R.A.HAWILEH Glenn Department of Civil Engineering Clemson UniversityClemsonSC 29634USA Department of Civil Engineering American University of SharjahSharjahUnited Arab Emirates materials Science and Engineering Research Institute American University of SharjahSharjahUnited Arab Emirates

This paper investigates the effect of differential support settlement on shear strength and behavior of continuous reinforced concrete(RC)deep beams.A total of twenty three-dimensional nonlinear finite element models were developed taking into account various constitutive laws for concrete material in compression(crushing)and tension(cracking),steel plasticity(i.e.,yielding and strain hardening),bond-slip at the concrete and steel reinforcement interface as well as unique behavior of spring-like support *** models are first validated by comparing numerical predictions in terms of load-deflection response,crack propagation,reaction distribution,and failure mode against that of measured experimental data reported in *** the developed models were successfully validated,a parametric study was designed and *** parametric study examined number of critical parameters such as ratio and spacing of the longitudinal and vertical reinforcement,compressive and tensile strength of concrete,as well as degree(stiffness)and location of support stiffness to induce varying levels of differential *** study also aims at presenting a numerical approach using finite element simulation,supplemented with coherent assumptions,such that engineers,practitioners,and researchers can carry out simple,but yet effective and realistic analysis of RC structural members undergoing differential settlements due to variety of load actions.

关键词： concrete continuous beams deep beams finite element modeling support settlement

Dye removal using some surface modified silicate minerals

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International Journal of mining Science and Technology 2014年第2期24卷 183-189页

作者： Selim K.A. youssef m.A. Abd El-Rahiem F.H. Hassan m.S. Central metallurgical Research and Development Institute

The objective of this work is to study the efficiency of some surface modified phyllosilicate minerals （bentonite and glauconite） in the removal of dyes from textile waste water. It is found that complete dye removal was achieved by using 10-25g modified glauconite from solutions having a dye concentration of 10-50 mg/L. Adsorption data were modeled using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms. Adsorption capacities and optimum adsorption isotherms were predicted by linear regression method. The analysis of experimental isotherms showed that Langmuir isotherm reasonably fit the experimental data in the studied concentration range for the adsorption of dye onto glauconite mineral surface where Freundlich isotherm fit the experimental data for the adsorption of dve onto bentonite mineral surface.

关键词： Glauconite Bentonite Dye removal modified silicate minerals Adsorption

Relative carcinogenicity of tacrolimus vs mycophenolate after solid organ transplantation and its implications for liver transplant care

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World Journal of Hepatology 2024年第4期16卷 650-660页

作者： Dorothy Liu mark m youssef Josephine A Grace marie Sinclair Department of Gastroenterology Austin HealthMelbourne 3084VictoriaAustralia Victorian Liver Transplant Unit Austin HealthMelbourne 3084VictoriaAustralia Department of medicine University of MelbourneMelbourne 3084VictoriaAustralia

BACKGROUND De novo malignancy is a leading cause of late morbidity and mortality in liver transplant *** immunosuppression has been shown to contribute to post-transplant malignancy(PTm)*** is emerging evidence on the differential carcinogenic risk profile of individual immunosuppressive drugs,independent of the net effect of *** inhibitors such as tacrolimus may promote tumourigenesis,whereas mycophenolic acid(mPA),the active metabolite of mycophenolate mofetil,may limit tumour *** transplantation(LT)is relatively unique among solid organ transplantation in that immunosuppression monotherapy with either tacrolimus or mPA is often achievable,which makes careful consideration of the risk-benefit profile of these immunosuppression agents particularly relevant for this ***,there is limited clinical data on this subject in both LT and other solid organ transplant *** To investigate the relative carcinogenicity of tacrolimus and mPA in solid organ *** A literature search was conducted using mEDLINE and Embase databases using the key terms“solid organ transplantation”,“tacrolimus”,“mycophenolic acid”,and“carcinogenicity”,in order to identify relevant articles published in English between 1st January 2002 to 11th August *** terms,synonyms and explosion of meSH terms,Boolean operators and truncations were also utilised in the *** lists of retrieved articles were also reviewed to identify any additional *** duplicates,abstracts from 1230 records were screened by a single reviewer,whereby 31 records were reviewed in ***-text articles were assessed for eligibility based on pre-specified inclusion and exclusion *** A total of 6 studies were included in this *** studies were large population registries or cohort studies,which varied in transplant era,type of organ transplanted and immunosuppression protocol us

关键词： Immunosuppression Solid organ transplantation Liver transplantation Carcinogenicity Tacrolimus mycophenolate

Evaluating ultrasound signals of carbon steel fatigue testing using signal analysis approaches

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Journal of Central South University 2014年第1期21卷 232-241页

作者： m.m.Padzi S.Abdullah m.z.Nuawi S.m.Beden z.m.Nopiah Department of mechanical and materials Engineering Universiti Kebangsaan Malaysia

The application of ultrasound techniques to monitor the condition of structures is becoming more prominent because these techniques can detect the early symptoms of defects such as cracks and other *** early detection of defects is of vital importance to avoid major failures with catastrophic *** assessment of an ultrasound technique was used to investigate fatigue damage *** tests were performed according to the ASTm E466-96 standard with the attachment of an ultrasound sensor to the test *** 1045 carbon steel was used due to its wide application in the automotive industry.A fatigue test was performed under constant loading stress at a sampling frequency of 8 *** sets of data acquisition systems were used to collect the fatigue strain signals and ultrasound *** of the signals were edited and analysed using a signal processing *** methods were used to evaluate the signals,the integrated Kurtosis-based algorithm for z-filter technique(I-kaz) and the short-time Fourier transform(STFT).The fatigue damage behaviour was observed from the initial stage until the last stage of the fatigue *** results of the I-kaz coefficient and the STFT spectrum were used to explain and describe the behaviour of the fatigue damage.I-kaz coefficients were ranged from 60 to 61 for strain signals and ranged from 5 to 76 for ultrasound signals.I-kaz values tend to be high at failure point due to high amplitude of respective *** spectrogram displays the colour intensity which represents the damage severity of the strain signals.I-kaz technique is found very useful and capable in assessing both stationary and non-stationary signals while STFT technique is suitable only for non-stationary signals by displaying its spectrogram.

关键词： fatigue ultrasound signal analysis integrated Kurtosis-based algorithm for z-filter technique short-time Fouriertransform

Entanglement of the Thermal State of an Anisotropic XYz Spin Chain in an Inhomogeneous Constant magnetic Field

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Chinese Physics Letters 2012年第3期29卷 9-12页

作者： A.-S.F.Obada G.m.Abd Al-Kadar F.K.Faramawy A.A.youssef mathematics Department Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

A system of a two-qubit Heisenberg anisotropic XYz spin chain in an inhomogeneous constant magnetic field with the Dzyaloshinskii-moriya interaction is *** energy eigenvalues,the corresponding eigenstates and the thermal states of the system are *** entanglement is investigated according to Wootter's *** concurrence is studied against temperature for different values of the parameters involved.

关键词： system concurrence states

Environmental impact of radionuclide migration in groundwater from a low intermediate level radioactive waste repository

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Journal of Environmental Sciences 2001年第2期13卷 180-184页

作者： J S Wang z F Yang S S Li z m Wang Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90Sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

关键词： intermediate level radioactive waste repository Environmental impact of radionuclide migration in groundwater from a low

EFFECT OF GRAIN REFINING ON PRImARYαPHASE IN SEmI-SOLID A356 ALLOY PREPARED BY LOW SUPERHEAT POURING AND SLIGHT ELECTROmAGNETIC STIRRING

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Acta metallurgica Sinica(English Letters) 2008年第1期21卷 57-64页

作者： z. Liu W.m. mao z.D. zhao Faculty of material and Chemical Engineering Jiangxi University of Science and Technology Ganzhou 341000 China School of material Science and Engineering University of Science ＆ Technology Beijing Beijing 100083 China

The semi-solid slurry of A356 alloy, which is grain-refined by Al-Ti-B master alloy, is prepared by low superheat pouring and slight electromagnetic stirring. The effects of grain refining on the morphology and the grain size of the primary α phase in the slurry manufactured are researched. The results indicate that the slurry with particle-like and rosette-like primary α phases can be prepared by low superheat pouring and slight electromagnetic stirring from liquid A356 alloy grain-refined, in which the pouring temperature can be suitably raised. Compared with the A356 samples without grain refining, the grain size and particle morphology of primary α phase as well as the distribution of the grain with particle-like or rosette-like along radial in the ingot in A356 are markedly improved by grain refining.

关键词： Semi-solid Grain-refined Low superheat pouring Slight electromagnetic stirring A356 alloy Al-Ti-B

Is Li-ESWT effective in diabetic patients with severe erectile dysfunction?

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Asian Journal of Andrology 2022年第5期24卷 521-524页

作者： müslüm Ergün Osman Akyüz Department of Urology School of MedicineAtlas UniversityIstanbul 34200Turkey

Noninvasive low-intensity extracorporeal shockwave treatment(Li-ESWT)has been widely used to treat erection *** is no clear information regarding either the selection of patients for the treatment or the treatment *** this study,we aimed to investigate the efficacy of extracorporeal shockwave therapy in diabetic patients with severe erectile dysfunction(International Index of Erectile Function-5[IIEF-5]scores of 5 to 7).Sixty-three diabetes mellitus patients with erectile dysfunction having IIEF-5 scores of 5 to 7 and not showing a recovery of potency despite phosphodiesterase type 5 inhibitor therapy for the past 6 months were included in the *** patients were evaluated based on their IIEF-5 scores and Erection Hardness Scale *** IIEF-5 score(mean±standard deviation[s.d.])increased from 5.29±1.67 to 5.56±1.85,with a difference of 0.27±0.18(P>0.05).The Erection Hardness Scale scores(mean±s.d.),on the other hand,increased from 1.46±0.50 to 1.48±0.50,with a difference of 0.02±0(P>0.05).In conclusion,the response to phosphodiesterase type 5 inhibitors did not change after extracorporeal shockwave treatment in diabetes mellitus patients with severe erectile dysfunction(IIEF-5 scores of 5 to 7).

关键词： diabetes mellitus International Index of Erectile Function-5 score low-intensity extracorporeal shockwave treatment severe erectile dysfunction

Exploring physical features of anisotropic quark stars in Brans-Dicke theory with a massive scalar field via embedding approach

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Chinese Physics C 2022年第4期46卷 185-198页

作者： Abdelghani Errehymy G.mustafa youssef Khedif mohammed Daoud Laboratory of High Energy Physics and Condensed matter(LPHEmaC) Department of PhysicsFaculty of Sciences Aïn ChockHassanⅡUniversity of CasablancaB.P.5366 MaarifCasablanca 20100Morocco Department of Physics Zhejiang Normal UniversityJinhua 321004China Department of Physics Faculty of SciencesUniversity of Ibn TofailB.P.133Kenitra 14000Morocco Abdus Salam International Centre for Theoretical Physics MiramareTrieste 34151Italy

The main aim of this study is to explore the existence and salient features of spherically symmetric relativistic quark stars in the background of massive Brans-Dicke *** exact solutions to the modified Einstein field equations are derived for specific forms of coupling and scalar field functions using the equation of state relating to the strange quark matter that stimulates the phenomenological mIT-Bag model as a free Fermi gas of *** use a well-behaved function along with the Karmarkar condition for class-one embedding as well as junction conditions to determine the unknown metric *** radii of strange compact stars viz.,PSR J1416-2230,PSR J1903+327,4U 1820-30,CenX-3,and EXO1785-248,are predicted via their observed mass for different values of the massive Brans-Dicke *** explore the influences of the mass of scalar field m_(ϕ),coupling parameter ωBD,and bag constant B on state determinants and perform several tests on the viability and stability of the constructed stellar ***,we find that our stellar system is physically viable and stable as it satisfies all the energy conditions and necessary stability criteria under the influence of a gravitational scalar field.

关键词： Brans-Dicke gravity karmarkar's condition exact solutions strange stars mIT bag EoS anisotropy