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Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

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国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri Mohammad sadegh Mirdehghan Mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children

Ranking of design scenarios of TMD for seismically excited structures using TOPSIS

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1372-1386页

作者： sadegh ETEDALI Department of Civil Engineering Birjand University of TechnologyBirjand 97175-569Iran

In this paper,desigh scenarios of a tuned mass damper(TMD)for seismically excited structures are ***,10 design scenarios in two cases,namely unconstrained and constrained for the maximum TMD,are considered in this study.A free search of the TMD parameters is performed using a particle swarm optimization(PSO)algorithm for optimum tuning of TMD ***,nine criteria are adopted with respect to functional,operational,and economic views.A technique for order performance by similarity to ideal solution(TOPSIS)is utilized for ranking the adopted design scenarios of *** studies are conducted on a 10-story building equipped with *** results indicate that the minimization of the maximum story displacement is the optimum design scenario of TMD for the seismic-excited structure in the unconstrained case for the maximum TMD ***,H2 of the displacement vector of the structure exhibited optimum ranking among the adopted design scenarios in the constrained case for the maximum TMD *** findings of this study can be useful and important in the optimum design of TMD parameters with respect to functional,operational,and economic perspectives.

关键词： seismic-excited building TMD optimum design PSO design scenario TOPSIS

Numerical study of cavitating flow in orifices and its effect on spray characteristics

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Journal of Hydrodynamics 2018年第5期30卷 908-919页

作者： Morteza ghorbani Mechatronics Engineering Program Faculty of Engineering and Natural Science Sabanci University Department of Biomedical Engineering and Health Systems KTH Royal Institute of Technology

The bubbly flow regime inside orifices has significant effects on several applications, and studying its trend along an orifice could be helpful in identifying the flow mechanism in various situations. The flow regime inside an orifice depends on the situation which has been specified for the orifice. Orifice geometry has a considerable effect on bubbly flow in injectors. Meanwhile, spray characteristics are influenced by the fuel flow inside an orifice, which has strong effects on the mixture of fuel-air. In this study, spray characteristics are studied for different values of the orifice angle. The cavitation phenomenon which occurs inside an orifice varies in intensity and patterns at different angles of the orifice and consequently has diverse effects on spray characteristics. The governing equations are solved by the SIMPLE algorithm. The spray flow is modeled by the discrete droplet method（DDM）, the droplet breakup is modeled by the WAVE model, and the primary breakup is modeled by the DIESEL BREAK UP model. In order to generate cavitation phenomenon inside orifices and investigate its effect on spray characteristics, the angle of orifice with respect to the injector body is varied and the problem is studied for different angles of orifice.

关键词： Cavitation iinjector angle microchannel spray

Analysis of Spray Evaporation in a Model Evaporating Chamber:Effect of Air Swirl

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Journal of Thermal Science 2023年第2期32卷 837-853页

作者： Mohammad sadegh ABEDINEJAD Department of Mechanical Engineering Faculty of EngineeringAlzahra UniversityTehranIran

Spray evaporation of liquid fuels in a turbulent flow is a common process in various engineering applications such as *** between fuel droplets(discrete phase)and fluid flow(continuous phase)have a considerable effect on liquid fuel *** this paper,both the single-and two-phase modeling of liquid fuel injection into a model evaporating chamber are *** influences of important issues such as turbulence models,coupling between gas phase and droplets,secondary break-up and air swirling on the current spray simulation are ***,the shear stress transport turbulence model,Taylor analogy break-up and two-way coupling models are applied to simulate the two-phase *** and spray of fuel droplets in hot air are modeled employing an Eulerian-Lagrangian *** current results show an acceptable agreement with the *** the fuel atomizer,bigger droplets are detected near the spray edge and minor droplets are situated in the *** increasing the droplets axial position,the droplets diameter decreases with a finite *** smaller droplets have a deeper penetration,but their lifetime is smaller and they evaporate sooner.A linear relation between penetration and lifetime of smaller droplets is *** droplet penetration and mean axial velocity of gas phase are observed for no air swirling *** effect of variation of swirl number on the lifetime of droplets is almost *** enhancing the swirl number,the uniformity of droplet size distribution is reduced and some large droplets are formed up in the domain.

关键词： secondary break-up droplet evaporation air swirling fuel spray gas-droplets coupling

Production of ultra-transparent glass-ceramics via controlled crystallization of nanocrystals in the glassy matrix of LAST

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International Journal of Minerals,Metallurgy and Materials 2014年第1期21卷 71-76页

作者： Mohammad sadegh Shakeri Materials and Energy Research Center(MERC)

Microstructural variation in glass-ceramics encompasses the range from nanocrystalline transparent materials to microcrystalline tough materials. In this investigation, the crystallization process was controlled for the development of ultra transparent LiEO-A1203-SiO2 glass-ceramics containing TiO2 as a nucleating agent （LAST）. Results of UV-Vis absorption spectra were compared with the expected theo- retical values calculated by the Rayleigh scattering method for the determination of ultra transparency. Results of the investigation illustrate that the control of crystallization increases the range of ultra transparency by the reduction of crystal size and their uniformity in the glassy matrix. Last but not the least, the optimized samples are ultra transparent approximately in the whole light wavelengths.

关键词： glass-ceramics transparency nanocrystals crystallization

Effect of Y_2O_3 on the crystallization kinetics of TiO_2 nucleated LAS glass for the production of nanocrystalline transparent glass ceramics

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International Journal of Minerals,Metallurgy and Materials 2013年第5期20卷 450-455页

作者： Mohammad sadegh Shakeri Materials and Energy Research Center (MERC) P.O. Box 31779-83634KarajIran

Crystallization kinetics of metastable B-quartz solid solution as a desirable phase for the production of trans- parent lithium aluminosilicate （LAS） glass ceramics was investigated in the presence of Y203. Accordingly, differential thermal analysis scans were performed thoroughly to study the mechanism of crystallization kinetics. The aim of this investigation is to discover the complicated mechanism of crystallization process in the presence of co-additives and ac- cordingly find a way for increasing the transparency of glass ceramics. It is shown that the bulk （3D） growth is intensively increased by the enhancement of Y203. Then again, reducing nucleation and increasing growth mechanisms were recog- nized for the LAS system in the presence of Y2O3. Results of the investigation illustrate that when co-additives are added to glasses, it is necessary to nucleate the optical component separately before the growth process.

关键词： glass ceramics lithium aluminosilicate yttria crystallization kinetics nanocrystals transparency

Fabrication,microstructure,and optical properties of nanocrystalline transparent LAST glass ceramics containing CeO_2

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 401-407页

作者： Mohammad sadegh Shakeri Materials and Energy Research Center (MERC)

In the present research, the effect of CeO2 dopant on the fabrication of transparent lithium aluminosilicate titanate （LAST） glass ceramics was investigated. Nanocrystallineβ-quartz solid solution （s.s.） was observed to be the main phase crystallized in this system. Com-parable refractive indices of the glassy matrix andβ-quartz s.s., as well as the incorporation of very fine grains size were determined as the main reasons for retaining the transparency of the glass ceramics. CeO2 was introduced as a suitable optical agent, playing a role as a network modifier in the glass ceramics, because it does not accelerate the growth process and retards the extended growth of crystals. Optical investi-gations indicate that the Fermi energy level, direct and indirect band gaps, and Urbach energy decrease with increasing nanocrystal content in the glassy matrix of specimens, which can be related to the expansion of conduction band, the enhancement of ionic bonds in the crystal lat-tice, and the enhancement of structural arrangement degree, respectively.

关键词： glass ceramics nanocrystals alurninosilicates titanates transparency optical properties

Line of sight waypoint guidance for a container ship based on frequency domain identification of Nomoto model of vessel

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Journal of Central South University 2016年第8期23卷 1944-1953页

作者： M.T.ghorbani Instituto Superior Tecnico Torre Norte-8.17 1049-001 Lisboa Portugal

CIFER software is used to identify steering and roll dynamics of a container ship. In this software, advanced features such as the Chirp-Z transform(CZT) and composite window optimization are applied to the time history of steering and roll dynamics to extract high quality frequency responses. From the extracted frequency responses, two linear transfer functions of Nomoto model are fitted for yaw and roll dynamics of the vessel. Based on the identified Nomoto model, a PID heading controller and a Kalman filter observer are constructed. The simulation results of heading controller for line of sight(LOS) waypoint guidance show excellent tracking of pilot inputs in the presence of wave induced motions and forces.

关键词： container ship Nomoto model Kalman filter frequency domain identification CIFER software

Oxidative desulfurization of model and real oil samples using Mo supported on hierarchical alumina–silica: Process optimization by Box–Behnken experimental design

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2759-2770页

作者： Nasim ghorbani Gholamreza Moradi Catalyst Research Center Department of Chemical EngineeringFaculty of EngineeringRazi UniversityKermanshahIran

The catalytic performance of Mo supported on hierarchical alumina–silica(Si/Al = 15) with Mo loadings of 3, 6 and 15 wt% was investigated for the oxidative desulfurization(ODS) of model and real oil samples. Hierarchical alumina–silica(h Al–Si) was synthesized by economical and ecofriendly silicate-1 seed-induced route using cetyltrimethylammonium bromide(CTAB) as mesoporogen. The effect of CTAB on the structure of catalyst was studied by characterization techniques. The results revealed that 6%Mo/h Al–Si had the highest sulfur removal compared to the other catalyst loadings. The effect of operating parameters was evaluated using Box–Behnken experimental design. The optimal desulfurization conditions with the 6%Mo/h Al–Si catalyst were determined at oxidation temperature of 67 ℃, oxidation time of 42 min, H2O2/S molar ratio of 8 and catalyst dosage of 0.008 g·ml^-1 for achieving a conversion of 95%. Under optimal conditions, different sulfur-containing compounds with initial concentration of 1000 ppm, Dibenzothiophene(DBT), Benzothiophene(BT) and Thiophen(Th), showed the catalytic oxidation reactivity in the order of DBT > BT>Th. According to the regeneration experiments, the 6%Mo/h Al–Si catalyst was reused 4 times with a little reduction in the performance. Also, the total sulfur content of gasoline and diesel after ODS process reached 156.6 and 4592.2 ppm, respectively.

关键词： Oxidative desulfurization Hierarchical alumina–silica Silicate-1 seed-induced route Box–Behnken experimental design