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JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2023年第9期20卷 2103-2125页

作者： javaherian, mohammad Movaheditabar, Parviz Shahid Chamran Univ Ahvaz Fac Sci Dept Chem POB *** Ahvaz Iran

Organic synthesis under green and efficient conditions is crucial for sustainable development. Among the 12 principles of green chemistry, using "safer solvents" is considered as one of the vitally necessary principles of correlated to the organic syntheses. Water is the most abundant and entirely safe molecule in the earth. It is a non-toxic, nonflammable, odorless, colorless, cheapest, renewable, easily accessible, and non-hazardous natural compound. Actually, water is the most ordinary and extraordinary solvent in the world. It is the only compound that naturally exists in three states of matter as solid, liquid, and gas. So, it occupies a unique position in nature due to its task as a solvent for biochemical reactions performed in the bodies of creatures. From the view point of organic synthesis, some of the chemical transformations such as Diels-Alder cycloaddition reaction are found to be more accelerated in water than traditional organic solvents. Ease of product separation is also another advantage of using water in organic reactions, even though, in the reactions that no remarkable rate acceleration is seen. This short review is focused on the importance of the role of water in promoting organic reactions. Organic reactions using water as a green solvent focusing on biphasic systems are reviewed. In this sense, aqueous phase heterogeneous catalysis reactions have a great interest. The advantages and limitations of using water as a green alternative solvent to volatile organic solvents are discussed. We have tried to show a clear image of the role of water in organic reactions. Thus, several considerable examples are given, and some related concepts such as hydrophobic effect, hydrogen bonding, phase-transfer catalysts, and superheated water as essential factors in organic reactions are concisely discussed. [GRAPHICS] .

关键词： In water On water Biphasic organic-aqueous systems Hydrophobic effect Phase-transfer catalyst Supercritical water

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Offshore wind development in the Great Lakes: challenges, resources and technical solutions

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OCEAN DYNAMICS 2025年第3期75卷 1-25页

作者： javaherian, mohammad Javad Wang, Andrew Hall, Lauren Zuo, Lei Univ Michigan Dept Naval Architecture & Marine Engn Ann Arbor MI 48109 USA Univ Michigan Cooperat Inst Great Lakes Res Ann Arbor MI 48109 USA Greenhills Sch Ann Arbor MI USA Virginia Tech Dept Mech Engn Blacksburg VA USA

Offshore wind energy offers a significant opportunity for renewable energy development in the Great Lakes. However, progress has been hampered by a range of challenges. This paper delves into the environmental, technological, infrastructural, regulatory, and human factors that have constrained offshore wind development in the region. While some aspects of these challenges have been studied, there remains a significant need for a comprehensive review that surveys the available data, tools, and technical approaches. This paper aims to fill this gap by systematically analyzing and presenting the challenges, along with the technical approaches, resources, and potential solutions required to overcome them. Special attention is given to address the freshwater ice challenge, a complex and critical issue that has not been fully addressed in the existing literature. By synthesizing current research and available methodologies, this paper seeks to provide a valuable resource for stakeholders involved in offshore wind energy development in the Great Lakes. The outcomes are intended to highlight the essential tools and approaches needed to overcome the existing barriers and unlock the substantial offshore wind energy potential of the Great Lakes. Additionally, the technologies and methodologies reviewed in this paper can be applied to Arctic regions or other bodies of water experiencing similar weather conditions and water/ocean dynamics.

关键词： Great lakes Offshore wind Fixed offshore wind platform Floating offshore wind platform Wind turbine Ice

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Flow Visualization, Hydrodynamics, and Structural Response of a Flexible Wedge in Water Entry Experiments

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JOURNAL OF SHIP RESEARCH 2023年第1期67卷 59-71页

作者： javaherian, mohammad Javad Ren, Zhongshu Gilbert, Christine Virginia Polytech Inst & State Univ Dept Aerosp & Ocean Engn Blacksburg VA 24061 USA

In this article, a free-falling flexible wedge into calm water is experimentally studied to understand the relationship between the spray root, peak pressure, and structural response. High-speed cameras are employed to record the spray root propagation, whereas hydrodynamic loading is measured with an array of pressure transducers. Stereoscopic-Digital Image Correlation (S-DIC) is used to measure deflection on the bottom of the wedge during the impact. Experiments are conducted from different drop heights to study the effect of impact velocity. Results are interpreted in light of an experimental data set of a rigid wedge of comparable dimensions. The comparison between the rigid and flexible wedges shows that due to fluid-structure interaction, the evolution of the spray root on a flexible wedge is slightly delayed compared to the rigid one.

关键词： high-speed craft hydroelasticity wedge drop visualization spray root S-DIC

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Virginia tech advanced towing carriage

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART M-JOURNAL OF ENGINEERING FOR THE MARITIME ENVIRONMENT 2023年第4期237卷 867-877页

作者： Gilbert, Christine javaherian, mohammad Javad Woolsey, Craig Shepheard, Mark Virginia Polytech Inst & State Univ Kevin T Crofton Dept Aerosp & Ocean Engn Blacksburg VA USA Virginia Polytech Inst & State Univ Kevin T Crofton Dept Aerosp & Ocean Engn 4505 Main St STE 435 Blacksburg VA 24061 USA

Virginia Tech has recently acquired a new towing carriage and vertical planar motion mechanism. The new towing carriage replaces the original carriage that was installed in the 1960s. The original carriage had a maximum speed of roughly 3 m/s, and the new carriage has a maximum speed of 7 m/s with the current wavemaker installation. The towing tank facility is used for both teaching and research activities in ocean engineering. The vertical planar motion mechanism includes two linear actuators to change the pitching and heaving behavior of a surface or subsurface test article to model different phenomena such as slamming or porpoising of surface vessels and vertical plane maneuvers for subsurface vessels. The focus of this paper is on the determination of the specifications for the towing tank to meet both teaching and research needs and the early resistance experiments that have been conducted during initial shake-down of the new facility. The authors will discuss how preliminary resistance experiments compare to the USNA towing tank facility.

关键词： Tow tank vertical planar motion mechanism high-speed hydrodynamics resistance experiments

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A Verification and Validation Study on a Loosely Two-Way Coupled Hydroelastic Model of Wedge Water Entry

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JOURNAL OF SHIP RESEARCH 2023年第3期67卷 197-212页

作者： Ren, Zhongshu javaherian, mohammad Javad Gilbert, Christine M. Virginia Polytech Inst & State Univ Kevin T Crofton Dept Aerosp & Ocean Engn Blacksburg VA 24061 USA

The interaction between the structural response and hydrodynamic loading (hydroelasticity) must be considered for design and operation purposes of high-speed planing craft made of composites that are prone to frequent water impact (slamming). A computational approach was proposed to study the hydroelastic slamming of a flexible wedge. The computational approach is a loose two-way coupling between a Wagnerbased hydrodynamic solution and a linear finite element plate model. Verification and validation (V&V) was performed on this coupled model. It was found that the model overpredicts rigid-body/spray root kinematics by <15% and hydrodynamic loading/ structural response by <26%.

关键词： V&V hydroelasticity fluid-structure interaction slamming

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Igneous rock powder as a heterogeneous multi-oxide nano-catalyst for the synthesis of 5-substituted-1H-tetrazoles in polyethylene glycol

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JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2022年第5期19卷 1805-1816页

作者： Movaheditabar, Parviz javaherian, mohammad Nobakht, Valiollah Shahid Chamran Univ Ahvaz Dept Chem Fac Sci Ahvaz Iran

The use of igneous rock nano-powder as a heterogeneous and recyclable multi-oxide nano-catalyst synthesizing of 5-substituted-1H-tetrazoles is reported. The igneous rock nano-powder was initially prepared by using the ball-milling method. Then, the structure, morphology, and magnetic properties of the prepared igneous rock nano-powder were characterized with some different spectroscopic, microscopic, and thermogravimetric techniques, such as FTIR, FESEM, XRF, XRD, Histogram, and EDS. The instrumental analyses showed that the prepared igneous rock powder is a mixture of metal oxides, such as Si, Al, Ca, Mg, Fe, Na, Mn, and Sr. It showed an excellent catalytic performance in synthesizing of 5-substituted-1H-tetrazoles through [3 + 2] cycloaddition reaction between sodium azide and nitrile compounds. Various aliphatic and aromatic nitriles and sodium azide were reacted in the presence of a catalytic amount of igneous rock nano-powder at 80 (o) C temperature in PEG-400. The protocol was simple and rapid, with suitable yields of the obtained tetrazoles. The igneous rock nano-powder is readily accessible, reusable, and holds potential for further application in acid-catalyzed organic syntheses and industrial requirements. Graphic abstract

关键词： Igneous rock Nano-powder Heterogeneous nano-catalyst Nitriles Sodium azide Tetrazoles Cycloaddition

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Vertical Wedge Drop Experiments as a Model for Slamming

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JOURNAL OF SHIP RESEARCH 2022年第4期66卷 297-314页

作者： Ren, Zhongshu javaherian, mohammad Javad Gilbert, Christine Virginia Polytech Inst & State Univ Kevin T Crofton Dept Aerosp & Ocean Engn Blacksburg VA 24061 USA

A deeper comprehension of hydrodynamic slamming can be achieved by revisiting the wedge water entry problem using flexible structures. In this work, two wedge models that are identical, with the exception of different bottom thicknesses, are ver-tically dropped into calm water. Pressure, full-field out-of-plane deflection, strain, vertical acceleration, and vertical position are measured. Full-field deflections and strains are measured using stereoscopic-digital image correlation (S-DIC) and strain gauges. A nondimensional number, R, quantifying the relative stiffness of the struc-ture with respect to the fluid load is revisited. An experimental parametric study on the effect of R on the nondimensional hydrodynamic pressure and the maximum strain is presented. It was found there is a sharp change in the trend of pressure and strain when R passes through a critical value. It was also discovered that the structural deformation causes a delay in the peak pressure arrival time and a reduc-tion in the peak pressure magnitude during the wedge water entry.

关键词： hydroelasticity wedge drop fluid-structure interaction slamming

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Nano-silica melamine trisulfonic acid as an efficient and reusable heterogeneous catalyst in esterification reactions

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JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2022年第10期19卷 4197-4207页

作者： javaherian, mohammad Latifi, Saeideh Heidarizadeh, Fariba Shahid Chamran Univ Ahvaz Dept Chem Fac Sci Ahvaz Iran

The use of nano-silica melamine trisulfonic acid as a reusable heterogeneous solid acid catalyst in the esterification reaction of carboxylic acids and alcohols is reported. The reaction conditions were optimized by testing temperature, each component of catalyst, feedstock ratios as well as load of catalyst. The synthesized catalyst was characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis techniques. The results showed that nano-silica melamine trisulfonic acid was an efficient dehydrating agent in the condensing reactions between different kinds of aliphatic and aromatic carboxylic acids and alcohols. The method was simple, rapid, straightforward, catalyst reusability, and holds potential for further application in acid-catalyzed organic synthesis and industrial requirements.

关键词： Nano-silica melamine trisulfonic acid Heterogeneous catalyst Acetylation Esterification Carboxylic acid Alcohol

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A comparative study of sonographic and clinical parameters in patient with upper trapezius muscle trigger point following dry needling and intramuscular electrical stimulation: a randomized control trial

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CHIROPRACTIC & MANUAL THERAPIES 2025年第1期33卷 1-14页

作者： Hadizadeh, Monavar Rahimi, Abbas Velayati, Meysam javaherian, mohammad Naderi, Farokh Keshtkar, Abbasali Dommerholt, Jan Shahid Beheshti Univ Med Sci Dept Physiotherapy Sch Rehabil Damavand Ave Tehran *** Iran Shahid Beheshti Univ Med Sci Akhtar Orthoped Hosp Dept Radiol Tehran Iran Univ Tehran Med Sci Sch Rehabil Dept Physiotherapy Tehran Iran Iran Univ Med Sci Dept Radiol Tehran Iran Univ Tehran Med Sci Sch Publ Hlth Dept Hlth Sci Educ Dev Tehran Iran Bethesda Physiocare Bethesda MD USA Myopain Seminars Bethesda MD USA Univ Maryland Sch Med Dept Phys Therapy & Rehabil Sci Baltimore MD USA

BackgroundThe most common cause of muscle pain is myofascial pain syndrome. Myofascial pain syndrome caused by sensitive areas called trigger points (TrP). Some physiotherapy modalities have acceptable effects for this disorder, but it is necessary to check the effects of placebo, appropriate dose, and long-term effects for each intervention. The aim of this study is to investigate the effect of intramuscular electrical stimulation (IMES) compared to dry needling (DN) on sonographic and clinical parameters in upper trapezius muscle *** is a randomized, single-blind control trial. The study period was from December 2, 2020, to April 10, 2021. Thirty volunteer patients with active upper trapezius TrP were randomly allocated into two groups: (1) IMES, (2) DN. Participants received interventions in three sessions. Primary outcome measurements were neck range of motion (ROM) and TrP circumference. Secondary outcome measurements were pain by visual analog scale (VAS), pain pressure threshold (PPT), disability, TrP longitudinal and transverse diameter, TrP stiffness, and muscle blood flow by vascular resistance index (RI). All outcome measurements were evaluated before, after, and one month after the intervention. If the data were normal, the repeated measure ANOVA test was used;if data were not normal, the Friedman test and the Kruskal-Wallis test was used. A significance level of 0.05 has *** increment was significantly more in the IMES group. TrP circumference decrement was significantly more in the IMES group. VAS changes did not show significant difference between two groups. The PPT improvement was significantly more in the IMES group. Disability changes were not significant. Longitudinal diameter changes were significantly more in the IMES group. TrP stiffness changes were not significant. The vascular RI decreased significantly in IMES *** seems that both IMES and DN have promising effects for improving upper trapezius T

关键词： Trigger point Myofascial pain Intramuscular electrical stimulation Dry needling Ultrasound imaging Upper trapezius

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Investigating the effects of core stability training on balance and gait in people with multiple sclerosis: A systematic review and meta-analysis

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MULTIPLE SCLEROSIS AND RELATED DISORDERS 2024年 87卷 105686-105686页

作者： Choobsaz, Haniyeh Sangtarash, Fatemeh javaherian, mohammad Hadizadeh, Monavar Univ Tehran Med Sci Sch Rehabil Dept Physiotherapy Tehran Iran Univ Tehran Med Sci Liver Transplantat Res Ctr Tehran Iran Shahid Beheshti Univ Med Sci Sch Rehabil Dept Physiotherapy Tehran Iran

Background and objectives: Balance disorders are a common concern in people with multiple sclerosis (PwMS). Core stability exercises are recommended as one of the treatment principles of rehabilitation in patients with balance disorders. This systematic review and meta-analysis investigate the effects of core stabilization exercises (CSE) on balance in PwMS. Methods: Online databases were searched from 1980 to December 15, 2022, including PubMed/Medline, Scopus, Web of Science, CINAHL, PEDro, Embase, and ProQuest to identify randomized controlled trials (RCTs) investigating the effects of CSE on balance in PwMS. The methodological qualities of the included studies were assessed using the modified Cochrane risk bias tool for randomized trials. Random-effect meta-analyzes were performed on the Berg balance test and Biodex balance system outcomes. Results: Seven RCTs were included in this study. A total of 379 patients (EDSS <6) were enrolled in the included studies. All researchers had applied CSE within six to ten weeks with the frequency of two to three sessions/week. According to qualitative results, core stability exercise significantly changes the most balanced outcomes. The meta-analyses illustrated that allocated participants to experimental groups had statistically significantly higher Berg balance test scores (standardized mean difference: 1.1;95 % CI: [0.1, 2.11) and insignificant lower Biodex score (standardized mean difference: -0.59;95 % CI: [-1.09, -0.091) compared to the control groups. Conclusion: Six to ten weeks of CSEs is an effective therapeutic strategy for balance improvement in PwMS that can help improve balance, especially in patients with moderate disability levels (EDSS3.5 -6). Further randomized clinical trials are needed to compare the efficacy of CSEs and routine balance training in PwMS.

关键词： Core stability exercise Balance Multiple sclerosis Systematic review Meta-analysis

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