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Chinese Chemical Letters 2009年第4期20卷 393-396页

作者： Yaghoub Sarrafi Marzieh Sadatshahabi kamal alimohammadi Department of Chemistry Mazandaran UniversityBabolsarIran

Pyridinium bromochromate has been found to be a highly efficient and selective reagent for the α-monobromination of 1,3- diketones and β-keto-esters in the absence of base, Lewis acid, or other catalyst. The product... 详细信息

关键词： α-Monobromination β-Ketoesters Pyridinium bromochromate 1,3-Diketones

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Microwave-assisted chemoselective copper-catalyzed amination of o-chloro and o-bromobenzoic acids using aromatic amines under solvent free conditions

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Chinese Chemical Letters 2009年第7期20卷 784-788页

作者： Yaghoub Sarrafi Manijeh Mohadeszadeh kamal alimohammadi Faculty of Chemistry Mazandaran UniversityBabolsarIran

Copper-catalyzed synthesis of N-aryl anthranilic acid derivatives using effective amination of 2-chloro and 2-bromobenzoic acid under microwave irradiation is reported. Some of the advantages of this method are high chemoselectivity, short reaction times, ease of work up procedure and elimination of the need for acid protection. 2009 Published by Elsevier B.V. on behalf of Chinese Chemical Society.

关键词： Microwave-assisted Copper-catalyzed Solvent free Amination N-Aryl anthranilic acid

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Modeling relationships between the network distance and travel time dynamics for assessing equity of accessibility to urban parks

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Geo-Spatial Information Science 2021年第3期24卷 509-526页

作者： Tahereh Ghaemi Rad Abbas alimohammadi GIS Department Faculty of Geomatics EngineeringCenter of Excellence in Geospatial Information TechnologyK.N.Toosi University of TechnologyTehranIran

Static models of accessibility are usually based on the fixed distance or Average Travel Time(ATT)*** of ignoring the traffic as a dynamic process affecting the accessibility through the change of Travel Time(TT),these models lead to unperceived temporal *** contrast to the consideration of the temporal Variation of TT(VTT)in the previous studies,the variation of traffic-related TT and its relations with network distance has not been *** this study,relations between VTT and network distance to access urban parks in Tehran megacity has been *** maps at five times of day are used to produce TT maps of Traffic Analysis Zones(TAZs)to their 3-closest *** of the Gini coefficients of accessibility show significant inequities of accessibility at different times of *** between the distance,ATT,and TT_(max) are modeled by statistical *** show both TT and TTmax have significant positive relations with distance and traffic and reach their maximum at 6 *** of significant relations between distance,ATT,TT_(max),and VTT provides interesting knowledge for the conversion of temporal measures of equity(TT)to a physical measure of equity(distance).A simple application of these findings for effective management of the spatiotemporal inequities is the definition of critical distances from public *** an example,to decrease the TT_(max) of TAZs to less than 12 min,their maximum distance to the closest parks should be less than 4 *** developed approach can be adopted for the accessibility evaluation of the other public services,particularly the health and education centers.

关键词： Spatiotemporal equity accessibility travel time variability Gini coefficient Lorenz curve urban parks Tehran megacity

Synthesis and characterization of new optically active copoly(amid-imide)s based on N-phthalimido-L-aspartic acid and aromatic diamines

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Chinese Chemical Letters 2010年第4期21卷 407-411页

作者： Khalil Faghihi Hamidreza alimohammadi Polymer Research Laboratory Department of ChemistryFaculty of ScienceIslamic Azad UniversityBranch ArakIran Yaung Research Club Islamic Azad UniversityBranch ArakIran

In this article,six new optically active copoly(amide-imide)s(10a-f) were synthesized through the direct polycondensation reaction of N-phthalimido-L-aspartic acid(4) with 1,5-diamino naphthalene(8),3,4-diamino benzophenone(9) in the presence of therphthahc acid(7),fumaric acid(6) and adipic acid(5) as a second diacid in a medium consisting of N-methyl-2-pyrrolidone,triphenyl phosphite, calcium chloride and *** resulting copolymers were fully characterized by means of FT-IR spectroscopy,elemental a...

关键词： High-performance polymers Copoly(amide-imide)s Direct polycondensation

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An investigation into the vibration of harmonic drive systems

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Frontiers of Mechanical Engineering 2013年第4期8卷 409-419页

作者： M.Masoumi H.alimohammadi School of Mechanical Engineering Semnan University School of Engineering Tarbiat Modares University

Harmonic drive systems are precise and specific transmission gear systems which are beneficial in terms of the high transmission ratio and almost zero *** inherent and spectacular properties result in using this mechanism in robotic and space sciences where the precision and lightwieght play an important *** paper presents a vibration analysis of harmonic drive systems using the shell *** of vibration for the flexspline and the circular spline of the system are derived and used to find the natural frequencies for both parts and,moreover,vibration response of the system under the operating condition is ***,obtained vibration equations are utilized to study the effects of different involved parameters such as the geometry of the flexspline and its gear tooth,eccentricity,and unbalancing on the vibrational behavior of the system.

关键词： harmonic drive system strain wave gearing mechanism vibration analysis natural frequencies

Evaluation of Wastewater Quality Compared to Well Water in Irrigation

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Open Journal of Ecology 2017年第4期7卷 271-278页

作者： Rahim alimohammadi Nafchi Agricultural Engineering Research Department Chahrmahal and Bakhtiari Agricultural and Natural Resources Research and Education Centre AREEO Shahrekord Iran

Water resources’ scarcity and increasing demand for water consumption have necessitated the use of unconventional water for optimized and sus-tainable consumption of water resources. The present project1 was con-ducted to investigate effects of domestic wastewater in comparison to well water, in a randomized complete block design with four treatments in three replications during three years. Concentrations of cations and anions in soil and plants as well as plants’ fresh and dry weight were measured in the present research per harvesting time. Results showed that the concentration of elements in alfalfa was higher in treatments being irrigated with wastewater resulting in the significant differences in nitrogen, phosphorus, sodium and chloride. The mean of elements’ concentration at soil with the depth of 0 - 30 cm in wastewater treatments was much more than those treatments irrigated with groundwater. Concentrations of elements in wastewater treatment with the depth of 30 - 60 cm were higher than well water treatments. Electrical conductivity, pH, total nitrogen, copper and iron significantly differed in different years and different treatments. Treatments irrigated with wastewater showed higher yield compared to treatments irrigated with well water (29,158 and 1252.5 kg per ha). Using wastewater of domestic treatment plant increased production per unit area and subsequently increased elements concentration in soil and plant.

关键词： Elements Concentration in Soil and Plant Irrigation Reusing Wastewater of Domestic Treatment Plant

Comparison of Water Use Efficiency in Alfalfa Using Water and Waste Water

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Journal of Agricultural Chemistry and Environment 2016年第4期5卷 191-199页

作者： Rahim alimohammadi Nafchi Agricultural Engineering Research Department Chaharmahal and Bakhtiari Agricultural and Natural Resources Research and Education Center AREEO Shahrekord Iran

Growth of cultural and economic level of societies has caused conversion of villages to cities and establishment of wastewater treatment plant in cities. Wastewater treat- ment plants discharge significant amounts of wastewater into natural waterways and their output at the most critical time (the hottest day that crop water need reaches to maximum due to physiological conditions) reaches to the highest amount. Hence, with regard to permanent and accessible wastewater and study on performance and production of forage per water or wastewater consumption unit, the research project was performed in form of statistical plan of totally random blocks with four treatments in three replications during three years. The results indicate that function of forage at the third year of project implementation has increased than the first and second years. Treatments 2 and 4 (the treatments to use wastewater) had greater function than treatments 1 and 3 (treatments that have irrigated with well water), found with significant difference. In average, function of forage (dry and wet) in treatments irrigated with wastewater than the treatments irrigated with well water has been greater to 37 and 32 percent regardless of consumption amount. Water con- sumption efficiency in the treatments to use wells water and wastewater equals to 0.867 and 1.09 kg production of dry hay per cubic meter of water or wastewater.

关键词： Alfalfa Water Wastewater Water Consumption Efficiency

Unveiling the potential impact of vitamin C in postoperative spinal pain

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中华神经外科杂志(英文) 2024年第3期10卷 1-6页

作者： Ranjbari Fatemeh alimohammadi Ehsan Clinical Research Development Center Taleghani and Imam Ali Hospital Kermanshah University of Medical Sciences Kermanshah Iran Department of Neurosurgery Kermanshah University of Medical Sciences Kermanshah Iran

Background Spinal surgery is a common procedure associated with significant postoperative pain, and identifying effective interventions to manage this pain is crucial for optimizing patient outcomes. This review assesses the existing literature to determine the overall impact of vitamin C supplementation on spinal postoperative *** Vitamin C could be considered a potentially beneficial adjunctive therapy for managing spinal postoperative pain, but its routine use requires further investigation.

关键词： Vitamin C Ascorbic acid Spinal surgery Postoperative pain Review article Background

Techno-Economic and Sustainability Analysis of Potential Cooling Methods in Irish Data Centres

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Journal of Electronics Cooling and Thermal Control 2021年第3期10卷 35-54页

作者： Lee Gibbons Tim Persoons Sajad alimohammadi School of Mechanical and Design Engineering Technological University Dublin Dublin Ireland Department of Mechanical Manufacturing & Biomedical Engineering Trinity College Dublin Dublin Ireland

11% of Irish electricity was consumed by data centres in 2020. The Irish data centre industry and the cooling methods utilised require reformative actions in the coming years to meet EU Energy policies. The resell of heat, alternative cooling methods or carbon reduction methods are all possibilities to conform to these policies. This study aims to determine the viability of the resell of waste heat from data centres both technically and economically. This was determined using a novel application of thermodynamics to determine waste heat recovery potential in Irish data centres, and the current methods of heat generation for economical comparison. This paper also explores policy surrounding waste heat recovery within the industry. The Recoverable Carnot Equivalent Power (RCEP) is theoretically calculated for the three potential cooling methods for Irish data centres. These are air, hybrid, and immersion cooling techniques. This is the maximum useable heat that can be recovered from a data centre rack. This study is established under current operating conditions which are optimised for cooling performance, that air cooling has the highest potential RCEP of 0.39 kW/rack. This is approximately 8% of the input electrical power that can be captured as useable heat. Indicating that Irish data centres have the energy potential to be heat providers in the Irish economy. This study highlighted the technical and economic aspects of prevalent cooling techniques and determined air cooling heat recovery cost can be reduced to 0.01 €/kWhth using offsetting. This is financially competitive with current heating solutions in Ireland.

关键词： Ireland Data Centres Techno-Economic Novel Cooling Methods Heat Resell Sustainability Energy Demand

Quantitative Detection of Inositol Hexakisphosphate (InsP6) in Crop Plants Using Polyacrylamide Gel Electrophoresis (PAGE)

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American Journal of Plant Sciences 2013年第12期4卷 1-6页

作者： Mohammad alimohammadi Nawab Ali Mariya Khodakovskaya Department of Applied Science University of Arkansas at Little Rock Little Rock USA

Inositol phosphates are essential for cell development and signaling in all living organisms. Inositol hexakisphosphate (InsP6) is the most abundant phosphoinositol in both plants and animals. While the concentration of inorganic phosphorous (Pi) is often limited in soil, some plants overcome this limitation by creating a phosphate reservoir that serves as a source of Pi during phosphate deficiency. Although this strategy benefits plant development and signaling under adverse environmental conditions, excessive accumulation of Pi in crop plants has raised serious concerns about its toxicity and ill effects on human health. Consumption of crop plants with high InsP6 content or food products made from these crops is found to reduce nutrient intake significantly by way of chelating essential metal cations in human and livestock fed by such plants. Therefore, it is necessary to determine InsP6 contents in crop plants. Several methods have been developed for the screening and detection of InsP6 in plants. These detection methods however, are complex, labor-intensive, and often provide inaccurate results. We have developed a fast, reliable, and cost-effective method for the detection and quantification of InsP6 in plants using polyacrylamide gel electrophoresis (PAGE) with potential applications in industry, quality control labs, and research projects.

关键词： Inositol Hexakisphosphate Polyacrylamide Gel Electrophoresis High-Performance Liquid Chromatography Nutrient Deficiency