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Simulating the Turbulent Hydrothermal Behavior of Oil/MWCNT Nanofluid in a Solar Channel Heat Exchanger Equipped with Vortex Generators

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Computer Modeling in Engineering & Sciences 2021年第3期126卷 855-889页

作者： Rachid Maouedj younes Menni Mustafa Inc Yu-Ming Chu Houari Ameur Giulio Lorenzini Unite de Recherche en Energies Renouvelables en Milieu Saharien URERMSCentre de Developpement des Energies RenouvelablesCDERAdrar01000Algeria Department of Physics Unit of Research on Materials and Renewable EnergiesFaculty of SciencesAbou Bekr Belkaid UniversityTlemcen13000Algeria Department of Mathematics Science FacultyFirat UniversityElazig23119Turkey Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung40402Taiwan Department of Mathematics Huzhou UniversityHuzhou313000China Hunan Provincial Key Laboratory of Mathematical Modeling and Analysis in Engineering Changsha University of Science&TechnologyChangsha410114China Department of Technology University Centre of NaamaNaama45000Algeria Department of Engineering and Architecture University of ParmaParco Area delle Scienze 181/AParma43124Italy

Re-engineering the channel heat exchangers(CHEs)is the goal of many recent studies,due to their great importance in the scope of energy transport in various industrial and environmental *** the internal geometry of the CHEs by using extended surfaces,i.e.,VGs(vortex generators),is the most common technique to enhance the efficiency of heat *** work aims to develop a newdesign of solar collectors to improve the overall energy *** study presents a new channel design by introducing *** FVM(finite volume method)was adopted as a numerical technique to solve the problem,with the use of Oil/MWCNT(oil/multi-walled carbon nano-tubes)nanofluid to raise the thermal conductivity of the flow *** study is achieved for a Re number ranging from12×10^(3) to 27×10^(3),while the concentration(φ)of solid particles in the fluid(Oil)is set to 4%.The computational results showed that the hydrothermal characteristics depend strongly on the flow patterns with the presence of VGs within the *** the Oil/MWCNT rates with the presence of VGs generates negative turbulent velocities with high amounts,which promotes the good agitation of nanofluid particles,resulting in enhanced great transfer rates.

关键词： Channel heat exchanger forced-convection Oil/MWCNT nanofluid CFD vortex generators

Nonlinear increase,invisibility,and sign inversion of a localized fs-laser-induced refractive index change in crystals and glasses

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Light(Science & Applications) 2020年第1期9卷 1398-1409页

作者： Jerome Lapointe Jean-Philippe Berube Yannick Ledemi Albert Dupont Vincent Fortin younes Messaddeq Real Vallee Centre d’Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalG1V 0A6 QuebecQCCanada

Multiphoton absorption via ultrafast laser focusing is the only technology that allows a three-dimensional structural modification of transparent ***,the magnitude of the refractive index change is rather limited,preventing the technology from being a tool of choice for the manufacture of compact photonic integrated *** propose to address this issue by employing a femtosecond-laser-induced electronic band-gap shift(FLIBGS),which has an exponential impact on the refractive index change for propagating wavelengths approaching the material electronic resonance,as predicted by the Kramers–Kronig *** by theoretical calculations,based on a modified Sellmeier equation,the Tauc law,and waveguide bend loss calculations,we experimentally show that several applications could take advantage of this ***,we demonstrate waveguide bends down to a submillimeter radius,which is of great interest for higher-density integration of fs-laser-written quantum and photonic *** also demonstrate that the refractive index contrast can be switched from negative to positive,allowing direct waveguide inscription in ***,the effect of the FLIBGS can compensate for the fs-laser-induced negative refractive index change,resulting in a zero refractive index change at specific wavelengths,paving the way for new invisibility applications.

关键词： waveguide millimeter refractive

A novel visible-light Nd-doped CdTe photocatalyst for degradation of Reactive Red 43:Synthesis,characterization,and photocatalytic properties

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Journal of Rare Earths 2016年第1期34卷 45-54页

作者： younes HANIFEHPOUR Nazanin HAMNABARD Bamin KHOMAMI Sang Woo JOO Bong-Ki MIN Jae Hak JUNG School of Mechanical Engineering Yeungnam University Department of Chemical and Biomolecular Engineering University of Tennessee Center for Research Facilities Yeungnam University School of Chemical Engineering Yeungnam University

Novel high-efficiency visible-light-sensitive Nd-doped CdTe nanoparticles were prepared with various doping concentra- tions of neodymium ion by a facile hydrothermal method. The reaction products were analyzed via X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, photoelectron spectroscopy （XPS）, and UV-Vis diffuse re- flectance spectroscopy techniques. Red shift was seen in the absorption band edge peak in the UV-Vis absorbance specmun with in- creasing Nd content. The XRD and XPS results confirmed that Nd ions successfully replaced Cd atoms and were incorporated into the crystal lattice of CdTe. SEM and TEM images indicated spherical structure and high crystallinity. Even at a very low Nd/CdTe molar ratio of 2 mol.%, Nd doping could greatly enhance the photocatalytic activity of CdTe. The photocatalytic activity of Nd-doped CdTe nanoparticles was evaluated by monitoring the decolorization of RRed 43 in aqueous solution under visible-light irradiation. The color removal efficiency of Nd0.08Cd0.9eYe and pure CdTe were 83.14% and 14.32% after 100 min of treatment, respectively. Among different amounts of the doping agent, 8 tool.% Nd indicated the highest decolorization. The presence of radical scavengers such as CF, CO3-, SO4〉, and huthanol was found to reduce the decolorization efficiency.

关键词： neodymium cadmium telluride hydrothermal photocatalyst rare earths

Numerical study of n-heptane/benzene separation by thermal diffusion column

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1745-1755页

作者： Neda Hashemipour Javad Karimi-Sabet Kazem Motahari Saeed Mahruz Monfared younes Amini Mohammad Ali Moosavian Department of Chemical Engineering Faculty of EngineeringArak UniversityArakIran Material and Nuclear Fuel Research School(MNFRS) Nuclear Science and Technology Research InstituteTehranIran Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran Department of Chemical Engineering Isfahan University of TechnologyIsfahanIran School of Chemical Engineering Faculty of EngineeringUniversity of TehranTehranIran

In this article,numerical simulations are performed to investigate the performance of the thermal diffusion column for the separation of n-heptane/benzene *** present work tried to optimize column by analyzing significant parameters such as feed flow rate,temperature and *** order to obtain the hydrodynamic and temperature and mass distribution inside thermal diffusion column,computational fluid dynamic(CFD) method is applied to solve the Navier-Stocks *** simulations are conducted to study the main parameters in both stationary and time-dependent *** using the separation work unit as a function of cut,the optimal cut for maximum SWU occurs within a limited range of 0.47-0.5 for feed rate between 0.5 and 4 g min^-*** findings reveal that the optimum feed rate in the range of optimum cut is about 1 g min^-*** transient study,results show that the best cut for reaching to steady-state condition is θ=0.5.

关键词： Thermal diffusion column(TDC) Computational fluid dynamic Separative work unit n-Heptane/benzene separation

CFD-Based Simulation and Analysis of Hydrothermal Aspects in Solar Channel Heat Exchangers with Various Designed Vortex Generators

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Computer Modeling in Engineering & Sciences 2021年第1期126卷 147-173页

作者： Mohamed Salmi younes Menni Ali J.Chamkha HouariAmeur Rachid Maouedj Ahmed Youcef Department of Physics University of M’silaM’sila28000Algeria Laboratory of Physics and Chemistry of Materials University of M’silaM’sila28000Algeria Unit of Research on Materials and Renewable Energies Department of PhysicsAbou Bekr Belkaid UniversityTlemcen13000Algeria Faculty of Engineering Kuwait College of Science and TechnologyDoha DistrictKuwait Center of Excellence in Desalination Technology King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Technology University Center of NaamaNaama45000Algeria Unite de Recherche en Energies Renouvelables en Milieu Saharien URERMSCentre de Developpement des Energies RenouvelablesCDERAdrar01000Algeria

The hydrothermal behavior of air inside a solar channel heat exchanger equipped with various shaped ribs is analyzed *** bottom wall of the exchanger is kept adiabatic,while a constant value of the temperature is set at the upper *** duct is equipped with a flat rectangular fin on the upper wall and an upstream V-shaped baffle on the lower ***,five hot wall-attached rib shapes are considered:trapezoidal,square,triangular pointing upstream(type Ⅰ),triangular pointing downstream(type Ⅱ),and equilateral-triangular(type Ⅲ)cross *** of the flow rates are also inspected for various Reynolds numbers in the turbulent regime(1.2×10^(4)-3.2×10^(4)).The highest performance(η)value is given for the Ⅱ-triangular rib case in all Re values,while the square-shaped ribs show a significant decrease in the η along the achieved Re *** η value at Remax is 2.567 for the Ⅱ-triangular roughness *** with the other simulated cases,this performance is decreased by about 3.768%in the case of Ⅰ-triangular ribs,15.249% in the case of Ⅲ-triangular ribs,20.802% in the case of trapezoidal ribs,while 27.541% in the case of square ribs,at the same ***,a comparison ismade with air-heat exchangers that have non-rough walls and contain cross-shaped VGs presented previously,in order to highlight the effectiveness of the rough surface presence in the baffled and finned *** obtained results indicated that the triangular-shaped rib(type Ⅱ)has the most significant hydrothermal behavior than the other *** indicates the necessity of roughness heat transfer surfaces for finned and baffled channels to improve significantly the performance of the air-heat exchangers they contain.

关键词： CFD heat exchanger vortex generators ribs hydrothermal aspects

Pancreatic stromal Gremlin 1 expression during pancreatic tumorigenesis

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Genes & Diseases 2022年第1期9卷 108-115页

作者： Joy M.Davis Binglu Cheng Madeline M.Drake Qiang Yu Baibing Yang Jing Li Chunhui Liu Mamoun younes Xiurong Zhao Jennifer M.Bailey Qiang Shen Tien C.Ko Yanna Cao Department of Surgery The University of Texas Health Science Center at HoustonHoustonTX 77030USA Department of Pathology&Laboratory Medicine The University of Texas Health Science Center at HoustonHoustonTX 77030USA Department of Neurology The University of Texas Health Science Center at HoustonHoustonTX 77030USA Department of Internal Medicine The University of Texas Health Science Center at HoustonHoustonTX 77030USA Department of Genetics Louisiana State University Health Sciences CenterNew OrleansLA 70112USA

Chronic pancreatitis(CP)is a major risk factor of pancreatic ductal adenocarcinoma(PDAC).How CP promotes pancreatic oncogenesis remains unclear.A characteristic feature of PDAC is its prominent desmoplasia in the tumor microenvironment,composed of activated fibroblasts and *** can be characterized as M1 or M2,with tumor-inhibiting or-promoting functions,*** reported that Gremlin 1(GREM1),a key pro-fibrogenic factor,is upregulated in the stroma of *** current study aimed to investigate the expression of GREM1 and correlation between GREM1 and macrophages within the pancreas during chronic inflammation and the development of *** mRNA in situ hybridization,we detected GREM1 mRNA expression withinα-smooth muscle actin(SMA)-positive fibroblasts of the pancreatic *** designated FibroblastsGrem1+marginally increased from CP to pancreatic intraepithelial neoplasia(PanIN)and *** PDAC,FibroblastsGrem1+increased with higher pathological tumor stages and in a majority of PDAC subtypes ***,FibroblastsGrem1+positively correlated with total macrophages(MacCD68+)and M2 macrophages(M2CD163+)in *** begin exploring potential molecular links between FibroblastsGrem1+and macrophages in PDAC,we examined the expression of macrophage migration inhibitory factor(MIF),an endogenous counteracting molecule of GREM1 and an M1 macrophage promoting *** IHC staining of MIF,we found MIF to be expressed by tumor cells,positively correlated with GREM1;by IHC co-staining,we found MIF to be negatively correlated with M2CD163+*** findings suggest that GREM1 expression by activated fibroblasts may promote PDAC development,and GREM1/MIF may play an important role in macrophage phenotype.

关键词： Fibroblasts Gremlin 1 Macrophage migration inhibitory factor Macrophages

Manufacturable Novel Nanogrease with Superb Physical Properties

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Nanomanufacturing and Metrology 2021年第4期4卷 289-297页

作者： Hammad younes Ding Lou Haiping Hong Huahui Chen Hongtao Liu Yinhuai Qiang Department of Electrical Engineering South Dakota School of Mines and TechnologyRapid CitySD 57701USA Department of Material Science and Engineering School of Mechanical and Electrical EngineeringChina University of Mining and TechnologyBeijing 100083China School of Material Science and Engineering China University of Mining and TechnologyXuzhou 221166China

High-performance nanogrease manufactured from carbon nanomaterials is observed to be stable and homogeneous and have superb physical properties,such as thermal and electrical conductivities,compared with current commercial greases made of lithium,calcium,and *** the first time,carbon nanomaterials have been observed to disperse well as the sole thickeners in oil systems,e.g.,polyalphaolefin and polyester(ROYCO),without the aid of any chemical ***-dimensional percolation network structures that exist among carbon nanomaterials are easily scalable,which can be attributed to the intermolecular van der Waals ***,the introduction of hydrogen bonding in any form to grease significantly increases its thermal and electrical conductivities and substantially reduces the weight percentage of carbon nanomaterials needed to fabricate stable *** example,loading of only 1.4 wt%hydroxyl-functionalized multiwalled carbon nanotube(MWNT-OH)with Krytox XHT750 oil leads to a 37.8%increase in thermal ***,75%glycerol,25% water,and 4.5 wt% MWNT-OH yielded the lowest electrical resistivity of 10.0 Ω *** finding can be extended to hydrogen bonding materials with functional groups,such as OH,COOH,F,and *** nanogrease reported in this study has been manufactured using the three-roll mill method,which is an easy and cost-effective method,as the loading weight percentage of carbon nanomaterials to fabricate stable grease decreases from 12 wt% to 3-4 wt%.Furthermore,the process is easily scalable,reproduced,and *** novel high-performance nanogrease has a high commercial value and numerous applications and could replace current commercial greases.

关键词： Nanogrease Three-dimensional network percolation structure Carbon nanomaterial Van der Waals forces Hydrogen bonding Thermal conductivity Electrical conductivity

Carbonization, Activation and Description of Activated Carbon from Palm Tree Leaves

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American Journal of Analytical Chemistry 2022年第9期13卷 331-345页

作者： Sara M. younes Basma M. El Dakiky Eman R. Sadik Chemical Engineering Department Borg El Arab Higher Institute Engineering and Technology Alex Egypt

One of the maximum residences of activated carbon is adsorption capacity, this significance grows every day in a variety of fields. One of its examples is water treatment, processing of potable, all of those residences deliver capacity of activated carbon in smell elimination and flavor in residues of dissolved natural and color. Activated carbon was made from the carbonization of palm tree leave’s stems and activated using calcium chloride, then tested with an increase in reactivity indicated by iodine adsorption test up to 68.6% reactivity increase in commercial sample and 48.7% in palm tree leaves sample. As the methods and precursors of activated carbon are very diverse and result in deferent adsorption properties, the primary test includes: carbonization of palm tree leaves, size reduction and classification of the charcoal produced, applying an iodine test on the non-activated sample, activating another sample with activating agent CaCl2 to comparison between the activated carbon and the non-activated carbon and shows the increasing in the adsorption capacity for elemental iodine in activated carbon.

关键词： Palm Tree Activated Carbon Adsorption Calcium Chloride Carbonization Activation Iodine Test

Survival rate and the determinants of progression from HIV to AIDS and from AIDS to the death in Iran: 1987 to 2016

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Asian Pacific Journal of Tropical Medicine 2019年第2期12卷 72-78页

作者： Mohammad Mirzaei Maryam Farhadian Jalal Poorolajal Parvin Afsar Kazerooni Katayoun Tayeri younes Mohammadi Department of Epidemiology School of Public Health Hamadan University of Medical Sciences Research Center for Health Sciences Department of Biostatistics School of Public Health Hamadan University of Medical Sciences Modeling of Noncommunicable Diseases Research Center Department of Epidemiology School of Public Health Hamadan University of Medical Sciences HIV/AIDS Research Center Shiraz University of Medical Sciences Iranian Research Center of HIV&AIDS Tehran University of Medical Sciences Social Determinants of Health Research Center School of Public Health Hamadan University of Medical Sciences

Objective: To examine the prognostic factors of progression from HIV to AIDS and AIDS to the death in people living with HIV/AIDS in ***: In this registry-based retrospective cohort study, we recruited 28 873 HIV-infected people from 158 Behavioral Diseases Counseling Centers of *** outcomes of interest included survival rates from HIV diagnosis to AIDS and from AIDS to the *** used Kaplan-Meier and Cox regression model to investigate survival rate and factors affecting on survival controlling effect of confounding ***: The one, three, five, and ten-year survival rate from HIV to AIDS were 85%, 73%, 61% and 32%, and for AIDS to death were 90%, 81%, 74% and 55%, *** Cox regression analysis indicated that the risk of progression from AIDS phase toward death in individuals with CD4 less than 200/mm^3, infected with tuberculosis(TB) and not treated by antiretroviral therapy(ART) was 2.17(95% CI: 1.62-2.90), 1.49(95% CI: 1.01-2.20) and 4.88(95% CI: 3.42-6.96) times higher *** risk of progression to AIDS in patients with baseline CD4 less than 200/mm^3 was 2.32(95% CI: 2.14, 2.51) times higher than patients with CD4 > 200/mm^3(P=0.001).On the other hand, tuberculosis increases the risk of death by 49.0%(P=0.04).The hazard ratio of death in patients who did not receive ART was 4.88(95% CI: 3.42, 6.96) times higher than patients who received ART(P<0.001).Conclusion: The early detection of HIV, the screening and treatment of TB and receiving the ART improve the survival of HIV/AIDS patients significantly, and prevent the transmission of HIV to other people.

关键词： HIV/AIDS Prognostic factor Survival time Tuberculosis Cohort study