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Analysis of Linear and Nonlinear Vibrations of Composite Rectangular Sandwich Plates with Lattice Cores

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Computers, Materials & Continua 2025年第1期82卷 223-257页

作者： alireza Moradi alireza Shaterzadeh Faculty of Mechanical Engineering Shahrood University of TechnologyShahroodP.O.Box ***Iran

For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this *** plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to *** this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain ***,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin *** the solution of this equation,the natural frequencies are ***,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple ***,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in *** confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is *** results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.

关键词： Free vibration composite sandwich plate lattice core galerkin method Duffing equation multiple scales method

Rainfall-induced wind erosion in soils stabilized with alkali-activated waste materials

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 465-480页

作者： alireza Komaei Abbas Soroush Seyed Mohammad Fattahi Hesam Ghanbari Department of Civil and Environmental Engineering Amirkabir University of TechnologyTehran159163431Iran

This study evaluates the efficacy of sustainable erosion control using slag-based alkali-activated cement crusts under varying rainfall and wind conditions. The rainfall intensities ranged from 30 mm/h to 120 mm/h, with durations ranging from 15 min to 90 min, and crust slopes of ∼2° (gentle) and 30° (steep). Wind tunnel experiments were conducted at wind velocities of 14 m/s, 21 m/s, and 28 m/s to investigate post-rainfall wind erodibility, along with changes in crust strength and microstructure analysis. The findings show the development of hydrated cementitious phases in alkali-activated material, which form around and between the particles during the alkaline activation process. Alkali-activated cement crusts significantly reduced erosion caused by rainfall and subsequent wind by several orders of magnitude. At the highest rainfall intensity of 120 mm/h, rainfall erosion was measured to be 1654.81 kg/m2 for untreated samples and 0.89 kg/m2 for treated samples, demonstrating a substantial 99.95% reduction in erosion due to the treatment. Similarly, at the highest wind speed tested, wind erosion was 122.75 kg/m2 for untreated samples and 0.095 kg/m2 for treated samples, indicating a significant 99.92% reduction in erosion due to the formation of an alkali-activated cement crust on the soil surface. However, exposure of the samples to 120 mm/h rainfall for 90 min resulted in a 5.2-fold increase in wind erosion compared to pre-rainfall conditions. Similarly, penetrometer results indicated a 37%–54% reduction in post-rainfall surface strength.

关键词： Rainfall erosion Alkali-activated material Wind erosion Crust formation

Psychometric Validation of the Persian Version of the Cannabis Use Disorder Identification Test

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Open Journal of Medical Psychology 2025年第1期14卷 71-96页

作者： Mahmood Amirinia Benjamin Ghasemi Parisa Aghazadeh alireza Mollazadeh Faculty of Medicine Sciences West Tehran Branch of Islamic Azad University Tehran Iran School of Environment and Natural Resources The Ohio State University Columbus Ohio USA Department of Psychology and Social Science Central Branch of Islamic Azad University Tehran Iran Department of Psychology Ashtian Branch of Islamic Azad University Ashtian Iran

The purpose of this paper is to look into how reliable and valid the Persian version of the Cannabis Use Disorder Identification Test-Revised (CUDIT-R-Pr) is. It will also compare the screening features of the CUDIT-R with those of the DSM-5 criteria for cannabis use disorder (CUD) based on the SCID-5-CT in a group of university students in Tehran, Iran. The study used the stratified random sampling technique to collect data from 541 students (19 to 24 years old) who used cannabis in Tehran universities in 2024. Confirmatory factor analysis confirmed the uni-dimensionality of the CUDIT-R-Pr. We checked the reliability of the CUDIT-R-Pr using Cronbach Alpha, split-half, inter-rater, test-retest stability over time, and parallel testing equivalence. The results indicated that CUDIT-R-Pr is reliable, reproducible, and responsive, with substantial agreement and adequate interpretability. The CUDIT-R shows that it can tell the difference between different levels of cannabis use severity, which is known as discriminant validity. Receiver operating characteristic analyses confirmed this, using an area under the receiver operating characteristics curve (AUC = 0.95) at a cutoff of ten or less. This allowed CUDIT-R-Pr to accurately predict any DSM-5 based on the highest correctly classified value (0.89), demonstrating high levels of sensitivity (0.96), specificity (0.69), and Youden value (0.65). The exact maximum Youden index (0.72) showed that CUDIT-R-Pr could also predict moderate DSM-5 with a cutoff of twelve or less. To validate and generalize the CUDIT-R-Pr for use among Iranian cannabis users, we need more research.

关键词： Cannabis Use Disorder Marijuana Psychometrics Validity Reliability Iran

Attitude of acute care nurses to the family presence during resuscitation and emotional intelligence:a cross sectional study

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Frontiers of Nursing 2025年第1期12卷 107-114页

作者： Amir Hooshmand alireza Sadeghi Sajad Noorian Mojtaba Senmar Yasamin Mehri Amirhosein Babaei Najmeh Chegini Student Research Committee Qazvin University of Medical SciencesQazvinIran Department of Statistics Faculty of ScienceUniversity of QomQomIran Student Research Committee Social Determinants of Health Research CenterResearch Institute for Prevention of Non-Communicable DiseasesQazvin University of Medical SciencesQazvinIran

Objective:Cardiopulmonary resuscitation(CPR)is one of the most important life-saving procedures in the *** to medical guidelines,family presence during CPR is still not accepted in some *** presence during CPR depends on the nurses’attitude,which is influenced by various *** intelligence(EI)helps nurses make wise decisions and display responsible behavior,which is necessary for proper and good performance in *** study’s purpose was to determine the attitude of acute care nurses toward family presence during CPR and its relationship with ***:The descriptive-analytical study was conducted among the nurses of acute care units(intensive care unit[ICU],critical care unit,and emergency department)in teaching hospitals of Qazvin University of Medical Sciences,Iran,in 2022-2023.A total of 186 nurses were included in the study using convenience *** data collection tools were a checklist of demographic characteristics,nurses’attitude toward the presence of family scale,and Siberia Schering’s EI *** collected data were analyzed using descriptive and analytical statistics and SPSS ***:The mean age of the participants was(32.05±6.93)*** 186 nurses participating in the study,127(68.3%)were women and the rest were *** mean score of attitude was 47.41±9.41(the minimum score of the nurses was 19 and the maximum score was 95).The mean score of EI was 99.27±8.86(the minimum score was 69 and the maximum score was 128).The results of Pearson’s correlation coefficient showed no significant relationship between the total score of attitude and EI of the participants(P=0.588).Data analysis showed that only the self-arousal dimension of EI has a significant relationship with the range of family self-control behaviors in attitude(P=0.037).Conclusions:The results showed that the nurses of acute care units have a positive attitude toward the presence of the family during CPR and have high ***

关键词： attitude cardiopulmonary resuscitation critical care emotional intelligence family presence nurse

Calculation of time-varying equivalent inductance and resistance of helical flux compression generators using the 2D filamentary method and dynamic matrix concept in the frequency domain

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Chinese Physics B 2010年第1期19卷 557-562页

作者： M.H.Khanzade Y.alinejad-Beromi A.Shoulaie Iran University of Science & Technology Semnan University

In this paper we present an approach to calculate the time-varying equivalent inductance and resistance of helical flux compression generators accurately. This approach is based on the 2D filamentary method and uses the dynamic matrix concept. By using this method, it is possible to consider both the effects of the armature presence and frequency on the inductance and resistance of the HFCGs. The latter effect has not been discussed in previous open literature. The validation of the presented method has been verified by measurement results.

关键词： helical flux compression generators liner seed current

A new approach for correlating of H_(2)S solubility in[emim][Lac],[bmim][ac]and[emim][pro]ionic liquids using two-parts combined models

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Chinese Journal of Chemical Engineering 2022年第4期35卷 521-527页

作者： alireza Afsharpour Faculty of Chemical and Materials Engineering Shahrood University of TechnologyShahroodIran

Two bi-part combined models containing reaction equilibrium thermodynamic model and an equation of state(EoS)including cubic plus association(CPA)or modified Soave-Redlich-Kwong(SRK),were employed to correlate H_(2)S solubility in ionic liquids[emim][Lac],[bmim][Ac]and[emim][Pro].RETM and CPA/mSRK are responsible for chemical and phase equilibria calculations,*** RETM defines a complex formation reaction between an H_(2)S and two IL molecules into the liquid phase so that a complex in the form of H_(2)S(IL)_(2)is probable to *** the other side,CPA/mSRK EoSs perform phase equilibria computations to find pressure and vapor phase *** the case of CPA,both of H_(2)S and the ionic liquids were considered as self-associating components which pursue 4 C and 2 B schemes,*** model computes the pure IL parameters using experimental density *** this work,critical properties were estimated through the modified Lydersen-Joback-Reid method,Eotvos and Guggenheim ***,the binary systems were investigated by applying *** presents average absolute deviations(AADs)equal to 2.41%,13.42%and 3.52%for[emim][Lac],[bmim][Ac],and[emim][Pro],***,the AADs obtained by mSRK are 3.75%,5.07%,and 6.06%,*** it is evident from the results,the combination of RETM with both CPA and m SRK EoSs will result in good correlation accuracy.

关键词： Solubility Thermodynamics Ionic liquids CPA RETM mSRK

Extraordinary adsorption of acidic fuchsine and malachite green onto cheap nano-adsorbent derived from eggshell

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1591-1602页

作者： Atefeh Moosavi Ali Akbar Amooey Ali alinejad mir Mojtaba Hedayati Marzbali Faculty of Chemistry University of MazandaranBabolsarIran Department of Chemical Engineering University of MazandaranBabolsarIran Chemical&Environmental Engineering School of EngineeringRMIT UniversityMelbourneVictoria 3000Australia

Removal of dyestuffs such as Acidic Fuchsine(AF)and Malachite Green(MG)being present in many forms in industries is vital to protect water reservoirs from their catastrophic effects on the *** study attempts to effectively eliminate these dyes using a low-cost and eco-friendly ***,as a biocompatible by-product,was initially characterized,then some modifications were conducted,and its morphology and chemical structure were then examined through(Atomic force microscopy)AFM,(Fourier-Transform Infrared Spectroscopy)FTIR,(Energy-Dispersive X-ray Spectroscopy)EDS and(Brunauer–Emmett–Teller)BET *** revealed that the modifications on raw material gave rise to a natural nano-adsorbent presenting porous medium appropriate for targeted adsorbate molecules with the average particle size and average pore diameter of 54 and^2 nm,*** groups on the adsorbent surface were also of importance to assist the adsorption of AF and *** effect of contact time,adsorbent dose,solution p H and initial concentration was ***-second order model accurately correlated the experimental kinetic data for both ***,the participation of intra-particle diffusion along with film diffusion in controlling the process was *** isotherm model fitted very well to the equilibrium data for both dyes and maximum monolayer adsorption capacity of AF and MG was accordingly calculated to be 5000 and 3333.33 mg·g-1 *** inherent characteristics of eggshell make it a potential material to remove contaminants from wastewater in future applications.

关键词： Egg shell Acidic Fuchsine Malachite Green Ultrahigh adsorption

Multi-ion Double Layers in a Magnetized Plasma

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Communications in Theoretical Physics 2015年第11期64卷 555-564页

作者： M.Shahmansouri H.alinejad M.Tribeche Department of Physics Faculty of ScienceArak University Department of Physics Faculty of Basic ScienceBabol University of Technology Faculty of Physics Theoretical Physics LaboratoryPlasma Physics GroupUniversity of Bab-EzzouarUSTHB

A theoretical investigation is carried out to study the existence,formation and basic properties of ion acoustic(IA) double layers(DLs) in a magnetized bi-ion plasma consisting of warm/cold ions and Boltzmann distributed *** on the reductive perturbation technique,an extended Korteweg de-Vries(KdV) equation is *** propagation of two possible modes(fast and slow),and their evolution are *** effects of obhqueness,magnitude of the magnetic field,ion concentration,polarity of ions,and ion temperature on the IA DL profile are analyzed,and then the ranges of parameters for which the IA DLs exist are investigated in details.

关键词： ion acoustic waves bi-ion plasma double-layers

Seismic hazard assessment of Tehran,Iran with emphasis on near-fault rupture directivity effects

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Earthquake Science 2018年第1期31卷 1-11页

作者： Ehsan Bazarchi Reza Saberi Majid alinejad Department of Civil and Environmental Engineering University of TabrizTabrizIran Nuclear Science and Technology Research Institute(NSTRI) TehranP.O.Box 113658486Iran Shakhes Pajouh Engineering Institute of Natural Hazards IsfahanP.O.Box 81655-1537Iran

Many destructive earthquakes happened in Tehran, Iran in the last centuries. The existence of active faults like the North Tehran is the main cause of seismicity in this city. According to past investigations, it is estimated that in the scenario of activation of the North Tehran fault, many structures in Tehran will collapse. Therefore, it is necessary to incorporate the near field rupture directivity effects of this fault into the seismic hazard assessment of important sites in Tehran. In this study, using calculations coded in MATLAB, Probabilistic Seismic Hazard Analysis （PSHA） is conducted for an important site in Tehran. Following that, deaggregation technique is performed on PSHA and the contribution of seis- mic scenarios to hazard is obtained in the range of distance and magnitude. After identifying the North Tehran fault as the most hazardous source affecting the site in 10000-year return period, rupture directivity effects of this fault is incorporated into the seismic hazard assessment using Somerville et al. （1997） model with broadband approach and Shahi and Baker （2011） model with narrowband approach. The results show that the narrowband approach caused a 27% increase in the peak of response spectrum in 10000-year return period compared with the conventional PSHA. Therefore, it is necessary to incorporate the near fault rupture directivity effects into the higher levels of seismic hazard assessment attributed to important sites.

关键词： Probabilistic seismic hazard analysis North Tehran fault rupture directivity effect deaggregation controlling earthquake