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Complexation of Sm^(3+) and pamidronate: A DFT study

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Journal of Rare Earths 2015年第3期33卷 310-319页

作者： Masoud Arabieh mohammad Hassan Khodabandeh mohammad hossein karimi-Jafari Carlos Platas-Iglesias Karim Zare Computational Chemistry Laboratory NSTRI 11365-8486 Tehran Iran Department of Chemistry Faculty of Science Shahid Beheshti University G.C. Evin 19839-63113 Tehran Iran Department of Bioinformatics Institute of Biochemistry and Biophysics University of Tehran 13145-1384 Tehran Iran Departamento de Química Fundamental Universidade da Coru?a Campus da Zapateira-Rúa da Fraga 10 15008 A Coru?a Spain

We reported a quantum mechanical study of the complexes formed between Sm3＋ and the bisphosphonate ligand pamidronate in aqueous solution. According to available experimental p K a values pamidronate was expected to exist in aqueous solution, at physiologically relevant p H, in its di- and tri-protonated forms（denoted by H3 L and H2L）. The most stable structures of the ligands and Sm3＋ complexes were found by using a detailed analysis of the conformational space with semiempirical and DFT methods. The results showed that both H2 L and H3 L bisphosphonates acted as a tridentate ligands in their complexes with Sm3＋. The addition of explicit water molecules to the coordination sphere of the metal not only gave different coordination numbers for H2 L and H3 L complexes（CN=9 and 10）, but also provided different trends in stabilization energies. The results highlighted the importance of considering not only an explicit first coordination shell, but also a second hydration shell, for an adequate description of this type of complexes in aqueous solution.

关键词： samarium radiopharmaceutical bisphosphonates solvent effects rare earths

Multidisciplinary design optimization of a dual-spin guided vehicle

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Defence Technology（防务技术） 2024年第7期37卷 133-148页

作者： Jalal karimi mohammad Reza Rajabi Seyed hossein Sadati Seyed Mahid hosseini Department of Aerospace Engineering Malek Ashtar University of TechnologyTehranIran

In this research,a Multidisciplinary Design Optimization approach is proposed for the dual-spin guided flying projectile design considering external and internal parts of the body as design *** this way,a parametric formulation is *** related disciplines,including structure,aerodynamics,guidance,and control are *** total mass,maximum aerodynamic control effectiveness,minimum miss distance,maximum yield stress in all subsystems,controllability and gyroscopic stability constraints are some of objectives/constraints taken into *** problem is formulated in All-At-Ones Multidisciplinary Design Optimization approach structure and solved by Simulated Annealing and minimax *** optimal configurations are evaluated in various *** resulted optimal configurations have met all design objectives and constraints.

关键词： Flying projectile optimal design All-at-ones multidisciplinary optimization Structure discipline Guidance and control discipline Aerodynamic discipline

Numerical Modeling of an Advanced Semi-SWATH Hull in Calm Water and Regular Head Wave

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Journal of Marine Science and Application 2021年第4期20卷 646-659页

作者： Arman Zare Hassan Sayyadi mohammad hossein karimi Department of Mechanical Engineering Sharif Universityof TechnologyTehran 11155-9567Iran Department of Mechanical and AerospaceEngineering Malek-Ashtar University of TechnologyEsfahan 1774-15875Iran

A small waterplane area twin hull(SWATH)has excellent seakeeping performance and low wave-making resistance,and it has been applied to small working craft,pleasure boats,and unmanned surface ***,with the increase in speed,the hydrodynamic resistance of SWATH will increase exponentially because of its large wet surface,followed by the uncomfortable situation of the hull underwater part relative to the water level and in terms of high trim by stern and high sinkage.A way to improve this situation is to reduce the depth of the draft at high speeds to ensure that all or a part of the volume of the submerged bodies is above the water *** on this idea,a new type of semi-SWATH hull form was analyzed in this *** two submerged bodies of the SWATH have a catamaran boat *** paper employed Sie-mens PLM Star-CCM+to study the hydrodynamic performance of an advanced semi-SWATH ***-hull resistance was estimated for both SWATH and CAT(CATAMARAN)modes in calm ***,the efect of fxed stabilizing fns with diferent angles on the vertical motions of the vessel in regular head waves was investigated with an overset mesh *** vertical motion responses were estimated at diferent wave encounter frequencies,and the present numerical method results have been verifed by already published experimental data.

关键词： Seakeeping performance Semi-SWATH Stabilizing fns Vertical motions Overset mesh

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad M.karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

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计算机用户中干眼的发生情况（英文）

国际眼科杂志 2017年第8期17卷 1410-1414页

作者： mohammad hossein Davari Ghasem karimi Seyed Hamid Sajjadi Birjand医科大学心血管疾病研究中心 Birjand医科大学眼科 Birjand医科大学医学系耳鼻喉科 Birjand医科大学医学系学生研究委员会

目的:明确计算机用户中干眼的发生情况,并将其与非使用者进行比较。方法:这是一项病例对照研究,于2015年在Birjand进行。研究的样本量确定为304例(计算机用户组和对照组每组152例)。两组都使用非随机抽样方法。泪液分泌试验用于评价研... 详细信息

目的:明确计算机用户中干眼的发生情况,并将其与非使用者进行比较。方法:这是一项病例对照研究,于2015年在Birjand进行。研究的样本量确定为304例(计算机用户组和对照组每组152例)。两组都使用非随机抽样方法。泪液分泌试验用于评价研究对象的干眼情况。研究对象填写问卷,所用问卷通过回顾文献基于客观情况发展来。使用SPSS进行卡方检验和Fisher检验,显著性水平为0.05。结果:干眼发生率:对照组为3.3%(5例),计算机用户组为61.8%(94例)。两组差异具有统计学意义(P<0.01)。眼部不适症状发生率:对照组为7.9%(12例),计算机用户组为34.2%(52例),两组之间的差异具有统计学意义(P<0.01)。计算机用户组,不同性别、不同年龄之间干眼发生率无统计学差异(P=0.8)。干眼患者平均每天使用计算机时间为6.65±3.52h,对照组为1.62±2.54 h(T=13.25,P<0.001)。结论:这一研究显示了使用计算机和干眼、眼部症状发生具有显著相关性。因此,管理人员需要对员工使用计算机工作的时间予以特别的关注。

关键词：干眼计算机用户生理影响

Special Issue: International Conference on Sustainable Energy Sources, Technologies and Systems 2023 (ICSESTS-2023)

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CLEAN ENERGY 2024年第3期8卷 136-137页

作者： Kumar, Ravinder Ahmadi, mohammad hossein Lovely Profess Univ Sch Mech Engn Phagwra 144411 Punjab India Shahrood Univ Technol Fac Mech Engn Shahrood Iran

Guest editorial introducing the special issue on the International Conference on Sustainable Energy Sources, Technologies and Systems 2023.

关键词： solar energy storage wind energy geothermal hydropower biofuels batteries

Analyzing the Interplay of Sintering Conditions on Microstructure and Hardness in Indirect Additive Manufacturing of 17-4PH Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1611-1620页

作者： Erika Lannunziata mohammad hossein Mosallanejad Manuela Galati Gabriele Piscopo Abdollah Saboori Integrated Additive Manufacturing Center Department of Management and Production EngineeringPolitecnico di TorinoCorso Duca Degli Abruzzi 2410129TurinItaly

Indirect additive manufacturing(AM)methods have recently attracted attention from researchers thanks to their great potential for cheap,straightforward,and small-scale production of metallic *** diffusion additive manufacturing(ADAM),a variant of indirect AM methods,is a layer-wise indirect AM process recently developed based on fused deposition modeling and metal injection ***,there is still limited knowledge of the process conditions and material properties fabricated through this process,where sintering plays a crucial role in the final consolidation of ***,this research,for the first time,systematically investigates the impact of various sintering conditions on the shrinkage,relative density,microstructure,and hardness of the 17-4PH ADAM *** this reason,as-washed samples were sintered under different time-temperature *** sample density was evaluated using Archimedes,computed tomography,and image analysis *** outcomes revealed that sintering variables significantly impacted the density of brown 17-4PH Stainless Steel *** results indicated more than 99% relative densities,higher than the value reported by Markforged Inc.(~96%).Based on parallel porosities observed in the computed tomography results,it can be suggested that by modifying the infill pattern during printing,it would be possible to increase the final relative *** microhardness of the sintered samples in this study was higher than that of the standard sample provided by Markforged *** at 1330℃ for 4 h increased the density of the printed sample without compromising its mechanical *** to X-ray diffraction analysis,the standard sample provided by Markforged ***“1330℃—4 h”one had similar stable phases,although copper-rich intermetallics were more abundant in the microstructure of reference *** study is expected to facilitate the adoption of indirect metal AM methods by different sector

关键词： Indirect additive manufacturing Atomic diffusion additive manufacturing 17-4PH stainless steel Computed tomography Sintering

Assessment of electrostatic discharge sensitivity of nitrogen-rich heterocyclic energetic compounds and their salts as high energy-density dangerous compounds: A study of structural variables

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DEFENCE TECHNOLOGY 2024年第9期39卷 15-22页

作者： Keshavarz, mohammad hossein Bani, Sedigheh Heydari Bakhtiari, Reza hosseini, Seyyed Hesamodin Malek Ashtar Univ Technol Fac Appl Sci Esfahan 177415875 Iran

Nitrogen-rich heterocyclic energetic compounds (NRHECs) and their salts have witnessed widespread synthesis in recent years. The substantial energy-density content within these compounds can lead to potentially dangerous explosive reactions when subjected to external stimuli such as electrical discharge. Therefore, developing a reliable model for predicting their electrostatic discharge sensitivity (ESD) becomes imperative. This study proposes a novel and straightforward model based on the presence of specific groups (-NH2 or -NH-, -N = N+ -O(- )and -NNO2, -ONO2 or -NO2) under certain conditions to assess the ESD of NRHECs and their salts, employing interpretable structural parameters. Utilizing a comprehensive dataset comprising 54 ESD measurements of NRHECs and their salts, divided into 49/5 training/test sets, the model achieves promising results. The Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and Maximum Error for the training set are reported as 0.16 J, 0.12 J, and 0.5 J, respectively. Notably, the ratios RMSE(training)/RMSE(test), MAE(training)/MAE(test), and Max Error(training)/Max Error(test) are all greater than 1.0, indicating the robust predictive capabilities of the model. The presented model demonstrates its efficacy in providing a reliable assessment of ESD for the targeted NRHECs and their salts, without the need for intricate computer codes or expert involvement. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Electrostatic discharge sensitivity Heterocyclic energetic compounds containing azole compound Interpretable structural parameter Safety ELECTRIC SPARK SENSITIVITY THERMAL-DECOMPOSITION IMPACT SENSITIVITY NITRAMINES PERFORMANCE EXPLOSIVES PREDICTION

Improvement of Surface Mechanical and Tribological Characteristics of L-PBF Processed Commercially Pure Titanium through Ultrasonic Impact Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1034-1046页

作者： Iman Ansarian Reza Taghiabadi Saeid Amini mohammad hossein Mosallanejad Luca Iuliano Abdollah Saboori Department of Materials Science and Metallurgy Imam Khomeini International University(IKIU)QazvinIran Department of Mechanical Engineering University of KashanKashanIran Integrated Additive Manufacturing Center Department of Management and Production EngineeringPolitecnico di TorinoCorso Duca Degli Abruzzi 2410129TurinItaly

Multi-pass ultrasonic impact treatment(UIT)was applied to modify the microstructure and improve the mechanical and tribological characteristics at the near-surface region of commercially pure Ti(CP-Ti)specimens produced by the laser powder bed fusion(L-PBF)*** considerably refined the L-PBF process-related acicular martensites(α′-M)and produced a well-homogenized and dense surface microstructure,where the porosity content of 1-,3-,and 5-pass UITed samples was reduced by 43,60,and 67%,*** UITed samples showed an enhancement in their near-surface mechanical properties up to a depth of about 300μ*** nanoindentation results for the 3-pass UITed sample revealed an increase of about 53,45,and 220%in its nanohardness,H/E_(r),and H_(3)/E_(r)^(2)indices,*** stylus profilometry results showed that performing the UIT removed the L-PBF-related features/defects and offered a smooth *** roughness average(R_(a))and the skewness(R_(sk))of the 3-pass UITed sample were found to be lower than those of the L-PBFed sample by 95 and 223%,*** the UIT also enhanced the material ratio,where the maximum load-bearing capacity(~100%)in as-L-PBFed(as-built)and 3-pass UITed samples was obtained at 60-and 10-µm depths,*** tribological investigations showed that applying the UIT resulted in a significant reduction of wear rate and average coefficient of friction(COF)of *** instance,under the normal pressures of 0.05 and 0.2 MPa,the wear rate and COF of the 3-pass UITed sample were lower than those of the L-PBFed sample by 65 and 58%,and 20 and 17%,respectively.

关键词： Laser powder bed fusion Ultrasonic impact treatment Commercially pure Ti(CP-Ti) Surface mechanical properties Tribological properties