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Solute mixing in a permeable non-rectangular channel

International Journal of Sediment Research 2020年第2期35卷 134-145页

作者： Sonia Zebardast sayyed-Hassan Tabatabaei Fariborz Abbasi Manuchehr Heidarpour Department of Water Engineering Faculty of AgricultureShahrekord University Agricultural Engineering Research Institute (AERI) Agricultural ResearchEducation and Extension Organization (AREEO) 3. Department of Water EngineeringCollege of AgricultureIsfahan University of Technology

Understanding diffusion and solute transport,is regarded as a main activity in environmental management,sustainable development and sedimentation processes because of their role in diffusion of *** current paper presents an experimental study which was done in a parabolic channel with permeable and impermeable bed conditions in order to estimate the transverse mixing coefficient(TMC) and the maximum solute mixing length(SML) for different channel bed roughness coefficients and *** cross section of the channel was 0.5 m wide and 0.3 m deep with a parabolic shape(*** to furrow irrigation).Three levels of bed roughness coefficient of 0.02,0.04,and 0.06,and three discharges of 5,10,and 15 L/s were *** infiltration channel was applied at a low level and medium level as well as a case without *** the current experiments,sodium chloride was used as a soluble tracer and was injected into the water at mid depth in the upstream cross *** tracer concentration profile in the water and velocity profile were measured at eight cross sections in the *** results showed that the values of SML ranged between 20 and 46 m in impermeable and permeable beds channel beds *** assessment of usual discharge values,infiltration,and roughness coefficient of a furrow(agricultural field) indicated that the SML of the furrows were less than20 *** the current research,the average dimensionless mixing coefficient was found to be 0.17 in the nonrectangular ***,equations were developed to explain the TMC and SML in a permeable parabolic channel that could be beneficial in prediction of fertilizer transport in furrow irrigatio n.

关键词： Environmental hydraulics Fertigation Furrow irrigation Solute mixing length Transverse mixing coefficient

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Metal-Doped Brushite Cement for Bone Regeneration

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Journal of Bionic Engineering 2023年第6期20卷 2716-2731页

作者： Muhammad aqib Aneela Anwar Humayun Ajaz Samina Akbar Ahsan Manzoor Maham Abid Zohaib Waheed Qudsia Kanwal Department of Chemistry University of Engineering and TechnologyGT RoadLahore54890Pakistan Department of Chemistry University of LahoreLahore5400Pakistan

For the past several years,calcium phosphate cement was used in the biomedical *** biocompatibility,good bioactivity,self-setting qualities,minimum setting degree,appropriate toughness,and simple shape to accommodate any difficult geometry are among their most notable *** phosphate has some types and brushite is one of the most attractive mineral for bone repair *** is extensively employed in filling fractures and trauma treatments as a bone substituted *** kind of material can potentially be used as a medicine delivery *** replacement of metal,such as magnesium,zinc,and strontium ions,into the calcium phosphate structure is a major research topic these *** cement has low mechanical strength and quick setting *** is possible to produce biomaterials with higher mechanical *** adding metal that are great potential in controlling cellular density when included into *** a result,it is a successful method to develop quite well regenerative *** paper provides a detailed summary of the present achievements of metal-doped brushite cement for bone repair and healing *** major purpose of this work is to give a simple but thorough analysis of current successes in brushite cement doped with Zn,Mg,Sr,and other ions as well as to highlight new advancements and *** impact of metal replacement on cement physical and chemical properties,including microstructure,setting time,injectability,mechanical property,and ion release,is *** metal-doped cement has osteogenesis,angiogenesis,and antibacterial properties,as well as their prospective utility as drug carriers,also considered.

关键词： Calcium phosphate Brushite Bone cement Metal dopants Bone regeneration

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Road scene analysis for determination of road traffic density

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Frontiers of Computer Science 2014年第4期8卷 619-628页

作者： Omar AL-KADI Osama AL-KADI Rizik AL-sayyed Ja'far ALQATAWNA King Abdullah lI School for Information Technology University of Jordan Amman 11942 Jordan College of Engineering and Computer Science Australian National University Canberra ACT 0200 Australia

Road traffic density has always been a concern in large cities around the world, and many approaches were developed to assist in solving congestions related to slow traffic flow. This work proposes a congestion rate estimation approach that relies on real-time video scenes of road traffic, and was implemented and evaluated on eight different hotspots covering 33 different urban roads. The approach relies on road scene morphology for estimation of vehicles average speed along with measuring the overall video scenes randomness acting as a frame texture analysis indicator. Experimental results shows the feasibility of the proposed approach in reliably estimating traffic density and in providing an early warning to drivers on road conditions, thereby mitigating the negative effect of slow traffic flow on their daily lives.

关键词： road congestion image texture local binary pattern scene morphology

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Abkhandari (Aquifer Management): a Green Path to the Sustainable Development of Marginal Drylands

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Journal of Mountain Science 2005年第3期2卷 233-243页

作者： sayyed Ahang Kowsar Fars Research Center for Agriculture and Natural Resources P.O. Box 71365-458 Shiraz I.R. Iran

Recurrent droughts and occasional floods are the facts of life in drylands. The presence of innumerable societies in deserts is the living proof that even the extremely dry environments are livable; the secret is how to adapt to the situation. Floodwater management, the most important art of sedentarized desert dwellers, is the secret of living with deserts. Floodwater irrigation alone, or in combination with the artificial recharge of groundwater （ARG）, has sustained the Persians for millennia. The scientists at the Kowsar Floodwater Spreading and Aquifer Management Research, Training and Extension Station in the Gareh Bygone Plain have been working since January 1983 to revive this ancient art and upgrade it to the level of science. A summary of important findings is provided as follows： 1. Debris cones and coarse alluvial fans are the best places for the ARG as they provide the potential aquifer for groundwater storage. The recharged water may be used for irrigation on the lower lying, fine alluvium; 2. Flood is not a proverbial curse but a blessing in disguise, and the turbid floodwater is the best resource for the sustainable development of drylands; 3. Translocation of fine clay minerals eventually makes the vadose zone impermeable. Planting deep-rooted, drought-resistent trees and shrubs, and introducing sowbugs （Hemilepistus shirazi Schuttz） are reliable methods to increase infiltration rate and the saturated hydraulic conductivity of the ARG systems; 4. The moving sand stabilization is best achieved by spreading turbid floodwater onto them. Establishing of living windbreaks and planting of fodder trees and shrubs turn a sand menace into a verdant pasture; 5. The 10 year average of native forage yield in the ARG systems has been 445 kg·ha^-1·year^-1 as opposed to 92 kg·ha^-***^-1 for the control. At 4×4 m^2 spacing, Atriplex lentiformis （Torr.） Wats. can annually yield 1500 kg ha^-1 of dry matter and support 3 heads of sheep; 6. The stem- and fuel wo

关键词： Floodwater artificial recharge of groundwater (ARG) drylands sustainable development

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Synthesis of highly functionalized pyrroles from primary amines and activated acetylenes in water

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Chinese Chemical Letters 2012年第10期23卷 1119-1121页

作者： S.Zahra sayyed-Alangi Zinatossadat Hossaini Faramarz Rostami-Charati Department of Chemistry Azadshahr BranchIslamic Azad UniversityAzadshahrIran Department of Chemistry Qaemshahr BranchIslamic Azad UniversityQaemshahrIran Department of Chemistry Faculty of ScienceGonbad Kavous UniversityP.O.Box 163Gonbadlran

Stable derivatives of pyrroles were prepared using multicomponent reactions of dialkyl acetylenedicarboxylate, primary amine and propiolate in the presence of N-methylimidazole in water at room temperature in good yie... 详细信息

关键词： Propiolate Dialkyl acetylenedicarboxilates Multicomponent reactions N-methylimidazole

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Estimation of sediment load and erosion of different geological units: A case study from a basin of north-eastern Iran

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Journal of Mountain Science 2021年第6期18卷 1591-1608页

作者： Maryam TAJBAKHSHIAN Abolfazl MOSAEDI Mohamad Hosein MAHMUDY GHARAIE sayyed Reza MOUSSAVI HARAMI Department of Geology Ferdowsi University of MashhadMashhad ***Iran Department of Water Science and Engineering Ferdowsi University of MashhadMashhad ***Iran

Erosion of geological units and sediment load in rivers can be considered as the serious problems in recent *** sediment loads generate major hazards for water resources development,particularly in terms of loss of reservoir storage due to sedimentation and siltation of water distribution *** this paper,the performance of four sediment rating curve (SRC) development methods was evaluated for the Shirin Darreh River(SDR) basin (1750 km^(2)),located in North Khorasan Province,*** of flow discharge (Q) and suspended sediment flux (SSF)(Q-SSF pairs,N=957)and daily flow discharge,recorded by the Regional Water Company of North Khorasan (RWCNK) at the Qaleh-Barbar (QB) gauging site during 1989-2018 were *** flow discharge classification method performed best by meeting the desired criteria of most statistical indices,including normalized root mean square error (NRMSE),mean bias error (MBE),mean absolute error (MAE),index of agreement (d),and coefficient of determination (R^(2)).Based on the optimized method,the rate of suspended sediment transportation at the study site was estimated about2.7×10^(6) ton year^(-1).Erodibility of the exposed formations in the study area was estimated based on a factorial scoring model (FSM).Three indices,focused on the outcrop and erodibility,were calculated for the geological units at sub-basin and total *** deposits are the most extensive geological unit in the three sub-basins and the maximum formation outcrop ratio (FOR) and participation in erosion (PCE)were obtained for these rocks at total *** fact,marl unit can be regarded as the main source to supply the suspended sediments in the study basin.

关键词： Geological units Sediment rating curve Flow discharge Suspended sediment concentration Erodibility

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Kinetics of the water-gas shift reaction in Fischer-Tropsch synthesis over a nano-structured iron catalyst

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Journal of Natural Gas Chemistry 2010年第4期19卷 362-368页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht sayyed Faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi university of Mashhad Research Institute of Petroleum Industry of National Iranian Oil Company

Based on formate and direct oxidation mechanisms,three Langmuir-Hinshelwood-Hougen-Watson （LHHW） kinetic models of the water-gasshift （WGS） reaction over a nano-structured iron catalyst under Fischer-Tropsch synthesis （FTS） reaction conditions were derived and compared with those over the conventional *** conventional and nanostructured Fe/Cu/La/Si catalysts were prepared by co-precipitation of Fe and Cu nitrates in aqueous media and water-oil micro-emulsion,*** WGS kinetic data were measured by experiments over a wide range of reaction conditions and comparisons were also made for various rate *** rate expressions based on the formate mechanism with the assumption that the formation of formate is rate determining step were found to be the best.

关键词： kinetics water-gas-shift reaction iron catalyst Fischer-Tropsch synthesis

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Machine Learning-based USD/PKR Exchange Rate Forecasting Using Sentiment Analysis of Twitter Data

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Computers, Materials & Continua 2021年第6期67卷 3451-3461页

作者： Samreen Naeem Wali Khan Mashwani aqib Ali M.Irfan Uddin Marwan Mahmoud Farrukh Jamal Christophe Chesneau Department of Computer Science&IT Glim Institute of Modern StudiesBahawalpur63100Pakistan Institute of Numerical Sciences Kohat University of Science&TechnologyKohat26000Pakistan Department of Computer Science Concordia College BahawalpurBahawalpur63100Pakistan Institute of Computing Kohat University of Science and TechnologyKohat26000Pakistan Faculty of Applied Studies King Abdulaziz UniversityJeddah21577Saudi Arabia Department of Statistics The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Mathematics Universitéde CaenLMNOCampus IIScience 3Caen14032France

This study proposes an approach based on machine learning to forecast currency exchange rates by applying sentiment analysis to messages on Twitter(called tweets).A dataset of the exchange rates between the United States Dollar(USD)and the Pakistani Rupee(PKR)was formed by collecting information from a forex website as well as a collection of tweets from the business community in Pakistan containing finance-related *** dataset was collected in raw form,and was subjected to natural language processing by way of data *** variable labeling was then applied to the standardized dataset,where the response variables were divided into two classes:“1”indicated an increase in the exchange rate and“−1”indicated a decrease in *** better represent the dataset,we used linear discriminant analysis and principal component analysis to visualize the data in three-dimensional vector *** that were obtained using a sampling approach were then used for data *** machine learning classifiers—the simple logistic classifier,the random forest,bagging,naïve Bayes,and the support vector machine—were applied to the optimized *** results show that the simple logistic classifier yielded the highest accuracy of 82.14%for the USD and the PKR exchange rates forecasting.

关键词： Machine learning exchange rate sentiment analysis linear discriminant analysis principal component analysis simple logistic

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p-TSA-catalyzed one-pot synthesis and docking studies of some 5H-indeno[ 1,2-b]quinoline-9,11 (6H,10H)-dione derivatives as anticonvulsant agents

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Chinese Chemical Letters 2016年第5期27卷 721-725页

作者： Kamaal Ahmed Balkrishna Dubey sayyed Nadeem Birendra Shrivastava Pankaj Sharma Department of Pharmaceutical Chemistry TIT College of Pharmacy Anand Nagar Bhopal 462021 Madhya Pradesh India Department of Pharmacology Technocrats Institute of Technology-Pharmacy Anand Nagar Bhopal Modhya Pradesh 462021 India School of Pharmaceutical Sciences Jaipur National University Jaipur Rajasthan India

The present work describes a facile, one-pot three component environment friendly, green synthesis of a series of 5-（4-methoxyphenyl）-7,7-dimethyl-10-phenyl-7,8-dihydro-SH-indeno[ 1,2-b]quinoline- 9,11 （6H,10H）-dione derivatives 8（a-n）. 1,3-indanedione, awl-aldehyde and enaminone was thoroughly ground in the presence of catalytic amount of p-toluene sulfonic acid （p-TSA） to give the titled compounds in good yields. All the synthesized derivatives were evaluated for their anticonvulsant activity using the maximal electroshock （MES） method with phenytoin as a standard drug along with their neurotoxicity effect. Derivatives 8b, 8e and 8k exhibited significant anticonvulsant activity （P 〈 0.001）. The neurotoxicity study clearly revealed that all the tested compounds are non-toxic at a dose of 40 mg/kg. The molecular modeling studies also predicted good binding interactions of most active molecules with the serotonin 5-HT2A receptor. Therefore, it can be safely concluded that synthesized derivatives 8（a-n） would represent useful leads for further investigation in the development of a new class of anticonvulsant agents.

关键词： 5H-Indeno[1 2-b]quinoline One potp-toluene sulfonic acid (p-TSA) Anticonvulsant activity Molecular docking

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Pedestrian street and its effect on economic sustainability of a historical Middle Eastern city:The case of Chaharbagh Abbasi in Isfahan,Iran

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Geography and Sustainability 2023年第3期4卷 188-199页

作者： Soudabeh Shahmoradi sayyed Mahdi Abtahi Pedro Guimaraes Department of urban planning Iranian Knowledge-Based Company of Pezhvak Tarh IranianIsfahan Science and Technology TownIsfahan University of Technology BlvdIsfahanIran Department of Civil Engineering Isfahan University of TechnologyIsfahanIran Centre of Geographical Studies Associated Laboratory TERRAInstitute of Geography and Spatial PlanningLisboaPortugal

Pedestrianization is an urban revitalization strategy to enhance sustainability and livability in car-oriented *** many studies in this research field,the effects of pedestrianization on the economy of cities in developing countries still need further ***,the impact of this strategy on the tenant mix of com-mercial and historical areas in Middle East countries is *** address these inadequacies,we considered Chaharbagh Abbasi street,located in the heart of Isfahan,Iran,and investigated the impact of a pedestrianization project with particular emphasis on how it affects the economic sustainability of existent commercial ***-and post-project data along with field observations and quantifications used to assess structural replacements in trade,were analyzed with SPSS and ArcGIS *** results revealed unexpected outcomes,such as the closure of some traditional businesses(27.5%),a stagnation in sales(69%)and a decrease in job offers(84%)leading the local economy to a fragile ***,it was found that the footfall volume increased by 64% and 73% from the retailers’and pedestrians’*** evolution along with a wide opening of food and beverage stores(approximately 60%)makes the post-pedestrianization results more promising than earlier *** conclusion,these findings reinforce the importance of pedestrian streets in revitalizing economic activities in historical and commercial areas from the perspective of economic *** to the lack of similar investigations in Middle East countries,these findings can support decision-makers and urban planners to take preventive measures in preserving the diversity of individual small shops for upcoming urban rehabilitation projects in terms of pedestrianization.

关键词： Urban planning Pedestrianization Chaharbagh abbasi Sustainable Development Goals(SDGs) Economic sustainability Historic city centers

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