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Color and Gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated Weathering

Journal of Renewable Materials 2024年第2期12卷 305-323页

作者： Fatemeh Hassani Khorshidi saeed kazemi najafi Farhood najafi Antonio Pizzi Dick Sandberg Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyP.O.Box 16765-654TehranIran LERMAB University of LorraineBlvd des AiguillettesNancy54000France Wood Science and Engineering LuleåUniversity of TechnologySkellefteåSweden

The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin *** this purpose,the prepared coatings were applied to pine wood surfaces and weathered ***,color and gloss of the coatings were measured before and after the weathering *** emission scanning electron microscopy(FE-SEM)micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 *** magnetic resonance(13C-NMR)spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based *** calorimetric analysis(DSC)test revealed that the glass-transition temperature(Tg)of lignin nanoparticles modified with diethylenetriamine(DETA)was 112.8℃ and Tg of lignin nano-particles modified with ethylenediamine(EDA)was 102.5℃,which is lower than the Tg of un-modified lignin(114.6℃)and lignin modified with DETA(126.8℃)and lignin modified with EDA(131.3℃).The coatings modified with lignin nano-particles had a greater change in *** lignin nano-particles in the modified coating are trapping hydroxyl radicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodified polyurethane *** weathering test,the nano-lignin-based coating had a rougher surface with a lower contact angle(0.78°)compared to the unmodified polyurethane coating(0.85°).

关键词： Amination propylene carbonate lignin biopolymer polyurethane coating polyol UN SDG 13

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Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(NIPU)

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Journal of Renewable Materials 2023年第5期11卷 2171-2190页

作者： saeed kazemi najafi Farhood najafi Antonio Pizzi Fatemeh Hassani Khorshidi Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyTehranIran LERMAB University of LorraineBlvd des AiguillettesNancyFrance

Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and *** compounds are mainly used as reactants to make other *** biopolymers,lignin is regarded as the base of a new polymer in polyol *** present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the *** this aim,first,lignin was extracted from raw ***,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene *** results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified ***,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR ***,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample.

关键词： Polyol lignin diethylenetriamine ethylenediamine propylene carbonate polyurethanes NIPU

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Coupling of RANS and BEM Solvers for Simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： saeed najafi Mehdi POURMOSTAFA LIU Peng-fei Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into *** main concern is to apply the wake effect of ship stern on the propeller *** this paper,a coupled BEM(Boundary Element Method)/RANS(Renolds-Averaged Navier−Stokes)solver is used to simulate propeller behind the hull in the self-propulsion *** motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational *** unsteady boundary element method which is also known as panel method is chosen to estimate the propeller *** wakes are treated using a time marching wake alignment ***,a RANS code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANS *** on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time *** of the solver is carried out using the towing tank test report of a 50 m oceanography research *** factor and trust deduction coefficient are estimated ***,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANS BEM coupled method ship propeller self-propulsion wake sheet pattern

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Isoimperatorin alleviates acetic acid-induced colitis in rats

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Asian Pacific Journal of Tropical Biomedicine 2024年第4期14卷 147-153页

作者： Saied Goodarzi Amir Hossein Abdolghaffari Behnaz najafi Mostafa Pirali Hamedani saeed Tavakoli Mahshad Marvi Maryam Baeeri Narguess Yassa Abbas Hadjiakhoondi Mohammad Abdollahi Zahra Tofighi Medicinal Plants Research Center Faculty of PharmacyTehran University of Medical SciencesTehranIran Department of Toxicology and Pharmacology Faculty of PharmacyTehran Medical SciencesIslamic Azad UniversityTehranIran Department of Pharmacognosy Faculty of PharmacyTehran University of Medical SciencesTehranIran Medicinal Plants Research Center Institute of Medicinal PlantsACECRKarajIran International Campus School of Pharmacy Tehran University of Medical SciencesTehranIran Toxicology and Diseases group The Pharmaceutical Sciences Research CenterTehran University of Medical SciencesTehranIran Department of Toxicology and Pharmacology Faculty of PharmacyTehran University of Medical SciencesTehranIran

Objective:To investigate the effect of isoimperatorin on histopathological and biochemical changes in acetic acid-induced colitis ***:Colitis was induced by intracolonic administration of acetic acid solution(4%v/v)in *** were divided into six groups including the sham group,the negative control group,the dexamethasone-treated group,and the groups treated with isoimperatorin(0.1,1,and 10 mg/kg/d by gavage).The treatments were administered for three days and then colonic status was assessed by macroscopic,histopathological,and biochemical ***:Isoimperatorin significantly alleviated colonic damage in a dose-dependent manner and improved histological changes in rats with acetic acid-induced *** also significantly reduced myeloperoxidase,TNF-α,IL-1β,and malodialdehyde ***:Isoimperatorin alleviates acetic acid-induced colitis in rats and may be a potential therapeutic agent for the treatment of colitis.

关键词： Isoimperatorin Inflammatory bowel disease Acetic acid Colitis TNF-α IL-1β

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Review of application of artificial intelligence techniques in petroleum operations

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Petroleum Research 2023年第2期8卷 167-182页

作者： saeed Bahaloo Masoud Mehrizadeh Adel najafi-Marghmaleki Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Department of Petroleum Engineering School of Science and EngineeringKhazar UniversityBakuAzerbaijan Department of Petroleum Engineering Ahwaz Faculty of PetroleumPetroleum University of TechnologyAhwazIran

In the last few years,the use of artificial intelligence(AI)and machine learning(ML)techniques have received considerable notice as trending technologies in the petroleum *** utilization of new tools and modern technologies creates huge volumes of structured and un-structured *** and processing of these information at faster pace for the performance assessment and forecasting for field development and management is continuously growing as an important field of *** difficulties which were faced in predicting the operative features by utilizing the conventional methods have directed the academia and industry toward investigations focusing on the applications of ML and data driven approaches in exploration and production operations to achieve more accurate predictions which improves decision-making *** research provides a review to examine the use cases and application of AI and ML techniques in petroleum industry for optimization of the upstream processes such as reservoir studies,drilling and production *** challenges related to routine approaches for prognosis of operative parameters have been evaluated and the use cases of performance optimizations through employing data-driven approaches resulted in enhancement of decision-making workflows have been ***,possible scenarios of the way that artificial intelligence will develop and influence the oil and gas industry and how it may change it in the future was discussed.

关键词： Artificial intelligence Machine learning Upstream operation Oil and gas industry Petroleum systems Decision-making

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Propulsion Performance of Spanwise Flexible Wing Using Unsteady Panel Method

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Journal of Ocean University of China 2020年第3期19卷 505-518页

作者： najafi saeed LIU Pengfei Ocean Engineering and Technology Department Iranian National Institute for Oceanography(INIO)Tehran ***Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

In this paper, the propulsion performance of a spanwise flexible oscillating wing, which is broadly similar to the undulation of a fin fluke, is investigated. The geometry of the fluke underwent three prescribed harmonic oscillating motions simultaneously while surging with constant velocity. The effect of deflection phase angle, flexibility parameter, and wing tip deflection amplitude on thrust coefficient and swimming efficiency was studied. A low-order unsteady panel method coupled with a time stepping algorithm for free wake alignment is implemented in a computer program to estimate the propulsion efficiency of lifting bodies. A novel approach is introduced to evaluate the singular integrals of line vortices by using an adaptive mollifier function. This method is an efficient way to accelerate computational speed by reducing the order of problem from R^3 to body boundaries. Results present the significant effect of phase angle on the propulsion characteristics of oscillating fluke.

关键词： propulsion performance fin whale fluke flexible wing panel method wake alignment

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使用非定常粘性和无粘求解器研究双螺旋桨在不同船舶尾流场中的性能

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Journal of Marine Science and Application 2022年第2期21卷 92-105页

作者： saeed najafi Mehdi Pourmostafa Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Fatemi Ave.14155-4781 TehranIran Department of Maritime Engineering Amirkabir University of TechnologyHafez Ave.15875-4413 TehranIran

In this study,the performance of a twin-screw propeller under the influence of the wake field of a fully appended ship was investigated using a coupled Reynolds-averaged Navier–Stokes(RANS)/boundary element method(BEM)*** unsteady BEM is an efficient approach to predicting propeller *** applying the time-stepping method in the BEM solver,the trailing vortex sheet pattern of the propeller can be accurately captured at each time *** is the main innovation of the coupled ***,to ascertain the effect of the wake field of the ship with acceptable accuracy,a RANS solver was developed.A finite volume method was used to discretize the Navier–Stokes equations on fully unstructured *** simulate ship motions,the volume of the fluid method was applied to the RANS *** validation of each solver(BEM/RANS)was separately performed,and the results were compared with experimental ***,the BEM and RANS solvers were coupled to estimate the performance of a twin-screw propeller,which was affected by the wake field of the fully appended *** proposed model was applied to a twin-screw oceanography research *** results demonstrated that the presented model can estimate the thrust coefficient of a propeller with good accuracy as compared to an experimental self-propulsion *** wake sheet pattern of the propeller in open water(uniform flow)was also compared with the propeller in a real wake field.

关键词： Twin propeller Reynolds-averaged Navier-Stokes(RANS) Boundary element method(BEM) Time-stepping method(TSM) Wake sheet pattern Effective wake field

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Forest Road Detection Using LiDAR Data

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Journal of Forestry Research 2014年第4期25卷 975-980页

作者： Zahra Azizi Akbar najafi saeed Sadeghian Faculty of Natural Resources Tarbiat Modares University P.O. Box:46414–356 Noor IRAN Geomatics College of National Cartographic Center P.O. BOX: 13185-1684 Tehran IRAN

We developed a three-step classification approach for forest road extraction utilizing LiDAR data. The first step employed the IDW method to interpolate LiDAR point data （first and last pulses） to achieve DSM, DTM and DNTM layers （at 1 m resolution）. For this interpolation RMSE was 0.19 m. In the second step, the Support Vector Machine （SVM） was employed to classify the LiDAR data into two classes, road and non-road. For this classification, SVM indicated the merged distance layer with intensity data and yielded better identification of the road position. Assessments of the obtained results showed 63% correctness, 75% completeness and 52% quality of classification. In the next step, road edges were defined in the LiDAR-extracted layers, enabling accu- rate digitizing of the centerline location. More than 95% of the Li- DAR-derived road was digitized within 1.3 m to the field surveyed nor- rnal. The proposed approach can provide thorough and accurate road inventory data to support forest management.

关键词： forest road LiDAR SVM IDW method

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Sediment contribution from different geologic formations and land uses in an Iranian small watershed,case study

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International Journal of Sediment Research 2017年第2期32卷 210-220页

作者： Seyed Hamidreza Sadeghi saeed najafi Alireza Riyahi Bakhtiari Department of Watershed Management Engineering Faculty of Natural ResourcesTarbiat Modares University Department of Environmental Sciences Faculty of Natural ResourceTarbiat Modares University

Many intra and extra problems occurred due to unsustainable human use of natural resources leading to increasing sediment loads in the ***,few studies have been comprehensively conducted in progressing countries to prioritize sediment sources from different points of views,particularly in some countries like Iran where such valuable information is essential for proper watershed resources *** present study was therefore planned to assess the importance of potential sediment sources viz.,spatial sources(geologic units) and source types(land use units) in sediment yield in Idelo watershed as one of the important sub-watersheds of Sefidrood large Watershed in Zanjan Province,Iran,using composite *** addition,the results of the sediment fingerprinting approach were compared with those of field measurement data obtained from studying soil erosion types(viz.,sheet,rill and gully erosion).Toward this attempt,16 tracers were detected in different geologic units and land uses and the sediment yielded at the watershed *** results showed that the composite fingerprints of the different geologic units comprising As,N,Cu,Zn,OC and Co tracers could correctly distinguish 86% of the sediment source *** red gypsiferous marl contributed 85 percent in sediment *** regard to source types,the optimum composite fingerprint encompassed only N and Cu and provided a discriminatory efficiency of 90%.Besides that,the rangelands with 48.8% study area coverage had a significant contribution of 88% in sediment *** field measurements confirmed the reliability of results of fingerprinting approach in apportioning watershed scale sediment sources on the base of consistency of the two sets of *** was also understood from the results,besides successful applicability of composite fingerprinting in assessing the provenance of the sediment yielded at the watershed outlet that the geologic formations and land use types played differe

关键词： Composite fingerprinting Multivariate mixing model Soil erosion Spatial sources Source types

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The Herpetofauna of Iran: Checklist of Taxonomy, Distribution and Conservation Status

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Asian Herpetological Research 2015年第4期6卷 257-290页

作者： Barbod SAFAEI-MAHROO Hanyeh GHAFFARI Hadi FAHIMI Siamak BROOMAND Mahtab YAZDANIAN Elnaz najafi MAJD Seyyed saeed HOSSEINIAN YOUSEFKHANI Elham REZAZADEH Mahboubeh Sadat HOSSEINZADEH Reza NASRABADI Mehdi RAJABIZADEH Meysam MASHAYEKHI Alireza MOTESHAREI Alireza NADERI Seyed Mahdi kazemi Pars Herpetologists Institute Department of Environmental Sciences Faculty of Natural Resources University of Kurdistan Department of Biology Faculty of Science Ege University Department of Biology Faculty of Science Ferdowsi University of Mashhad Department of Biology Faculty of Scince Razi University Department of Biodiversity Institute of Science and High Technology and Environmental Sciences Graduate University of Advanced Technology Department of Environment Islamic Azad University Science and Research Natural History Museum of Iran Pardisan Nature Park Department of the Environment Department of Biology College of Sciences Qom Branch Islamic Azad University

We present an annotated checklist for a total 241 reptiles and 22 amphibians including 5 frogs, 9 toads, 7 newts and salamanders, 1 crocodile, 1 worm lizard, 148 lizards, 79 snakes and 12 turtles and tortoises, includes the most scientific literature up to August 2014 and also based on several field surveys conducted in different Provinces of Iran from 2009 to 2014. We present an up-to-dated checklist of reptiles and amphibians in Iran. We provide a comprehensive listing of taxonomy, names, distribution and conservation status of all amphibians and reptiles of Iran. This checklist includes all recognized named taxa, English names for classes, orders, families, species, subspecies along with Persian names for species, including indication of native and introduced species. For the first time we report two non-native introduced reptiles from natural habitats of Iran. Of the total 22 species of amphibians in Iran, 6（27.2%） are endemic and of the total 241 species of reptiles, 55（22.8%） are endemic. Of the 22 amphibians species in Iran, 3（13%） are Critically Endangered, 2（9%） are Vulnerable and of the 241 reptile species 3（1.2%） are Critically Endangered, 4（1.6%） are Endangered and 10（4.1%） are Vulnerable. Accordingly, this paper combines significant aspects of taxonomy, common names, conservation status and distribution of the Iranian herpetofauna.

关键词： Amphibians Anura Caudata Reptiles Crocodylia Squamata Testudines Persian common name

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