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Chinese Journal of Traumatology 2013年第1期16卷 46-50页

作者： Mansour Sayyah Gholamreza Khosravi manzardokht bigdeli Trauma Research Center Kashan University of Medi-cal Sciences Kashan I.R. Iran Trauma Nursing Research Center Kashan Universityof Medical Sciences Kashan I.R. Iran

Abstract：Objective:Falls are one of the life events leading to injury and in serious cases cause high morbidity and *** research was conducted to determine the fall incidence among female population of Kashan city from the years 2005 to ***:This was a retrospective research using existing data from the data bank of trauma center of Kashan University of Medical *** of all the female patients treated at local hospitals with complete hospitalisation kept at the center were examined for 4 consecutive years from 2005 to ***:A total of 2 094 female patients' records were examined.A significantly higher incidence of injuy occurred in 2008 compared to 2005 (P＜0.0001).In addition,the highest frequency of injury occurred in age group above 65 years (31.9％)and in group with elementary education level (42.8％).Conclusion:The results showed that fall incidences occurred in the old age group above 65 *** injuries at this age may cause ***,preventive measures should be taken,such as increasing the awareness of the aging population about the seriousness of fall incidence and encouraging the aged individuals to get involved in fitness program to remain physical fit and healthy。

关键词：出现频率女性患者创伤人口老龄化城市损伤生活事件

Clean synthesis of 1,8-dioxooctahydroxanthenes promoted by DABCO-bromine in aqueous media

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Chinese Chemical Letters 2010年第10期21卷 1180-1182页

作者： Mohammadali bigdeli Faculty of Chemistry Tarbiat Moallem University

An efficient procedure is reported for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthenes using a one-pot condensation of arylaldehydes and 5,5-dimethyl-l,3-cyclohexandione in the presence of DABCO-bromine （TDB） as an acid catalyst. To the best of our knowledge this is the first time that DABCO-bromine is used as an acid catalyst in aqueous media for this type of reaction. This method provides several advantages such as use of water as solvent, easy and clean synthesis, simple work up and versatility.

关键词： 1,4-Diazabicyclooctane (DABCO)-bromine Octahydroxyxanthene Aqueous media Arylaldehyde Dimedone

Wet cyanuric chloride promoted efficient synthesis of amidoalkyl naphthols under solvent-free conditions

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Chinese Chemical Letters 2009年第4期20卷 383-386页

作者： Gholam Hossein Mahdavinia Mohammad A.bigdeli Department of Chemistry Islamic Azad University-Marvdasht BranchMarvdashtIran Faculty of Chemistry Tarbiat Moalem University49 Mofateh St.TehranIran

An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of wet-cyanuric chloride （wet-TCT） as a catalyst. The reactions were carried out under solvent-free media. The present methodology offers several advantages such as excellent yields, simple procedure and eco-friendly reaction condition.

关键词： One-pot Cyanuric chloride Catalyst Amidoalkyl naphthol Multicomponent

Controllable reactor based hybrid HVDC breaker

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High Voltage 2020年第5期5卷 543-548页

作者： Amir Heidary Mehdi bigdeli Kumars Rouzbehi Department of Electrical Engineering Zanjan BranchIslamic Azad UniversityZanjanIran 2Department of System Engineering and Automatic ControlUniversity of SevilleSevilleSpain

Short circuit fault occurrence in high-voltage DC (HVDC) systems causes extremely high currents in a fast raising time that does not experience current zero-crossing. To protect HVDC systems/grids against fault current, fast HVDC breaker is an essential equipment. This study presents the design procedure of a novel HVDC breaker based on solid-state controllable reactor which is able to reduce the fault current's rate of rise and fault current amplitude to less than grid nominal current in the breaking process. The main achievement of the proposed HVDC breaker is that not only breaker does not encounter fault current, but also none of the series HVDC equipment is influenced by the fault. The designed breaker performance is studied by PSCAD/EMTPS, and then the simulation results are validated by the developed laboratory experimental setup.

关键词： fault EMTP nominal

P-Dodecylbenzenesulfonic acid(DBSA),a Brфnsted acid-surfactant catalyst for Biginelli reaction in water and under solvent free conditions

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Chinese Chemical Letters 2011年第8期22卷 903-906页

作者： Mohammad Ali bigdeli Ghazaleh Gholami Enayatollah Sheikhhosseini Faculty of Chemistry Tarbiat Moallem University49 MofatehTehranIran

We report herein the use of p-dodecylbenzenesulfonic acid（DBSA） as a catalyst for a one-pot Biginelli reaction to afford 3,4- dihydropyrimidinone derivatives in good to excellent *** reaction proceeds efficiently in water and under solvent free *** of results indicate that although the yields are high and comparable for both methods,the reaction times are considerably shorter under solvent free conditions.

关键词： Biginclli reaction Dihydropyrimidinonc P-Dodecylbenzenesulfonic acid(DBSA)

LOCV calculation of the equations of state and properties of rapidly rotating neutron stars

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Chinese Physics C 2018年第6期42卷 128-133页

作者： A.H.Farajian M.bigdeli S.Belbasi Department of Physics University of Zanjan

In this paper, we have investigated the structural properties of rotating neutron stars using the numerical RNS code and equations of state which have been calculated within the lowest order constrained variational（LOCV）approach. In order to calculate the equation of state of nuclear matter, we have used UV（14）＋TNI and AV（18） *** have computed the maximum mass of the neutron star and the corresponding equatorial radius at different angular velocities. We have also computed the structural properties of Keplerian rotating neutron stars for the maximum mass configuration, MK, RK, fK and jmax.

关键词： LOCV method neutron star matter equation of state rotating neutron star

Covalently anchored sulfonic acid on silica gel(SiO_2-R-SO_3H)as an efficient and reusable heterogeneous catalyst for the one-pot synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions

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Chinese Chemical Letters 2009年第5期20卷 539-541页

作者： Gholam Hossein Mahdavinia Mohammad A.bigdeli Yaser Saeidi Hayeniaz Department of Chemistry Islamic Azad University-Marvdasht BranchMarvdashtIran Faculty of Chemistry Tarbiat Moalem University49 Mofateh StreetTehranIran

A highly efficient one-pot synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions catalyzed by sulfonic acid covalently anchored onto the surface of silica gel is reported. All types of aldehydes, including aromatic, unsaturated, and heterocyclic, are used. The silica gel/sulfonic acid catalyst （SiO2-R-SO3H） is completely heterogeneous and can be recycled.

关键词： 1,8-Dioxooctahydroxanthenes Heterogeneous catalysis SiO2-R-SO3H Reusable

Surrogate models for the prediction of damage in reinforced concrete tunnels under internal water pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第8期22卷 632-656页

作者： Alireza bigdeli Aydin SHISHEGARAN Mohammad Ali NAGHSH Behnam KARAMI Arshia SHISHEGARAN Gholamreza ALIZADEH School of Civil Engineering Iran University of Science and TechnologyTehran 16846-13114Iran Institute of Structural Mechanics Bauhaus-University WeimarWeimar D-99423Germany School of Civil Engineering Isfahan University of TechnologyIsfahan ***Iran International Institute of Earthquake Engineering and Seismology Tehran 19537-14453Iran School of Civil Engineering Islamic Azad UniversityTehran 158474331Iran

In the present study,the performance of reinforced concrete tunnel(RCT)under internal water pressure is evaluated by using nonlinear finite element analysis and surrogate *** parameters,including the compressive and tensile strength of concrete,the size of the longitudinal reinforcement bar,the transverse bar diameter,and the internal water pre ssure,are considered as the input *** on the levels of variables,36 mix designs are selected by the Taguchi method,and 12 mix designs are proposed in this *** fiber reinforced concrete(CFRC)or glass fiber reinforced concrete(GFRC)is considered for simulating these 12 *** component regression(PCR),Multi Ln equation regression(MLnER),and gene expression programming(GEP)are employed for predicting the percentage of damaged surfaces(PDS)of the RCT,the effective tensile plastic strain(ETPS),the maximum deflection of the RCT,and the deflection of crown of *** error terms and statistical parameters,including the maximum positive and negative errors,mean absolute percentage error(MAPE),root mean square error(RMSE),coefficient of determination,and normalized square error(NMSE),are utili zed to evaluate the accuracy of the *** on the results,GEP performs better than other models in predicting the *** results sh ow that the internal water pressure and the mechanical properties of concrete have the most effect on the damag e and deflection of the RCT.

关键词： Gene expression programming(GEP) Taguchi method Finite element(FE)analysis Effective tensile plastic strain(ETPS) Deflection Damage

Silica supported perchloric acid(HClO_4-SiO_2):A mild,reusable and highly efficient heterogeneous catalyst for the synthesis of amidoalkyl naphthols

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Chinese Chemical Letters 2008年第10期19卷 1171-1174页

作者： Gholam Hossein Mahdavinia Mohammad A.bigdeli Majid M.Heravi Department of Chemistry Islamic Azad University-Marvdasht BranchMarvdashtIran Faculty of Chemistry Teacher Training University49 Mofateh StreetTehranIran Department of Chemistry School of SciencesAzzahra UniversityVanakTehranIran

An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of HClO4-SiO2 as a heterogeneous catalyst. The reactions were carried out under reflux and solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, easy work-up and ecofriendly reaction condition. The catalyst is easily prepared, stable, reusable and efficient under the reaction conditions.

关键词： One-pot HClO4-SiO2 Heterogeneous catalyst Amidoalkyl naphthol Multicomponent reaction

A series of 1,8-dioxooctahydroxanthenes are prepared using trichloroisocyanuric acid

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Chinese Chemical Letters 2009年第11期20卷 1275-1278页

作者： Mohammad A.bigdeli Firouzeh Nemati Gholam Hossein Mahdavinia Hamideh Doostmohammadi Faculty of Chemistry Tarbiat Moallem University49 Mofateh St.TehranIran Department of Chemistry Faculty of ScienceSemnan UniversitySemnanIran Department of Chemistry Islamic Azad University-Marvdasht BranchMarvdashtIran

A series of aromatic aldehydes are turned in to 3,3,6,6-tetramethy1-9-aryl-1,8-dioxooctahydroxanthene derivatives using trich/oroisocyanuric acid （TCCA） as the catalyst.

关键词： 1,8-Dioxooctahydroxanthenes Trichloroisocyanuric acid Homogenous catalyst 5,5-Dirnethyl-1,3-eyclohexandione