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Chinese Chemical Letters 2015年第9期26卷 1113-1116页

作者： seyed Meysam Baghbanian Department of Chemistry Ayatollah Amoli BranchIslamic Azad University

In this work,the natural nanozeolite clinoptilolite（Nano CP） was successfully functionalized by propylsulfonic acid and applied as efficient heterogeneous catalyst for the synthesis of quinoxaline derivatives in aqueous *** nanocatalyst was characterized by various techniques such as ChN,XRD,FT-IR,BET,TGA/DTA,SEM,TEM and *** results show its applicability as green,reusable and promising catalyst in organic *** was found that the nanocatalysts could be recycled and reused eight times without significant loss of catalytic activities.

关键词： Clinoptilolite heterogeneous catalyst Nanozeolite Propylsulfonic acid O_uinoxalines

Performance of Iranian Okra Ecotypes Under Various Accelerated Aging Conditions

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horticultural Plant Journal 2019年第1期5卷 17-23页

作者： Ghasem Parmoon seyed Amir Moosavi seyed Ataollah Siadat Department of Agronomy Faculty of Agriculture University of Mohaghegh Ardabili Department of Plant Production and Genetics Faculty of Agriculture Khuzestan Agricultural Sciences and Natural Resources University

Knowledge of seed quality and preservation of okra seeds is very limited, and the main purpose of this study was to simulate the condition of seed quality loss during storage and the physiological implications, which has led to seed vigor loss. A factorial experiment was conducted with the aim of studying the mechanism of longevity loss of the three endemic okra ecotypes of Iran(Ahwaz, Isfahan, Mashhad) in response to different accelerated aging durations(24, 48, 96, and 192 h). The accelerated aging condition was incubation of seeds to the temperature of 40 °C with 99% humidity. Germination of okra seeds was improved at 24 and 48 h compared to non-aged seeds, while at 192 h of accelerated aging, seed germination(49%) reduced to 50% of its value in 48 h(96.4%). Our results revealed that Iranian okra ecotypes were able to survive accelerated aging conditions up to 48 h. Antioxidant enzyme activity decreased with the increase in aging durations. Among investigated cultivars, seedling vigor of Mashhad ecotypes was the most sensitive to aging treatments. Our results revealed that the seed reservoir use efficiency value was 66%lower when exposed to 192 h of aging compared to the control. The cultivar Isfahan exhibited the minimum reduction of antioxidant activity,and, interestingly, this ecotype was the most aging tolerant.

关键词： Abelmoscul esculentus antioxidant activity deterioration germination protein seed vigor

Potassium forms in calcareous soils as affected by clay minerals and soil development in Kohgiluyeh and Boyer-Ahmad Province,Southwest Iran

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Journal of Arid Land 2018年第2期10卷 217-232页

作者： Sirous ShAKERI seyed A ABTAhI Department of Agriculture Payame Noor UniversityTehran 19395-3697Iran Department of Soil Science College of AgricultureShiraz UniversityShiraz 71964-84334Iran

Potassium（K） is known as one of the essential nutrients for the growth of plant species. The relationship between K and clay minerals can be used to understand the K cycling, and assess the plant uptake and potential of soil K fertility. This study was conducted to analyze the K forms（soluble, exchangeable, non-exchangeable and structural） and the relationship of K forms with clay minerals of calcareous soils in Kohgiluyeh and Boyer-Ahmad Province, Southwest Iran. The climate is hotter and drier in the west and south of the province than in the east and north of the province. A total of 54 pedons were dug in the study area and 32 representative pedons were selected. The studied pedons were mostly located on calcareous deposits. The soils in the study area can be classified into 5 orders including Entisols, Inceptisols, Mollisols, Alfisols and Vertisols. The main soil clay minerals in the west and south of the study area were illite, chlorite and palygorskite, whereas they were smectite, vermiculite and illite in the north and east of the province. Due to large amount of smectite and high content of organic carbon in soil surface, the exchangeable K in surface soils was higher than that in subsurface soils. It seems that organic matter plays a more important role than smectite mineral in retaining exchangeable K in the studied soils. Non-exchangeable K exhibited close relationships with clay content, illite, vermiculite and smectite. Although the amount of illite was the same in almost all pedons, amounts of structural and non-exchangeable K were higher in humid regions than in arid and semi-arid regions. This difference may be related to the poor reservoir of K~＋ minerals like palygorskite and chlorite together with illite in arid and semi-arid regions. In humid areas, illite was accompanied by vermiculite and smectite as the K~＋ reservoir. Moreover, the mean cumulative non-exchangeable K released by CaCl_2 was higher than that released by oxalic acid, which may be

关键词： clay minerals potassium forms calcareous soils oxalic acid K+ reservoir Iran

Effects of 946-nm thermal shift and broadening on Nd^(3+):YAG laser performance

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Chinese Physics B 2015年第12期24卷 342-345页

作者： seyed Ebrahim Pourmand Ghasem Rezaei Department of Optics and Laser Engineering Estahban Branch Islamic Azad University Department of Physics College of Sciences Yasouj University

Spectroscopic properties of flashlamp pumped Nd^3＋：YAG laser are studied as a function of temperature in a range from-30℃ to 60℃. The spectral width and shift of quasi three-level 946.0-nm inter-Stark emission within the respective intermanifold transitions of ^4F3/2→^4I9/2are investigated. The 946.0-nm line shifts toward the shorter wavelength and broadens. In addition, the threshold power and slope efficiency of the 946.0-nm laser line are quantified with *** lower the temperature, the lower the threshold power is and the higher the slope efficiency of the 946.0-nm laser line is,thus the higher the laser output is. This phenomenon is attributed to the ion-phonon interaction and the thermal population in the ground state.

关键词： 946-nm Nd:YAG laser thermal broadening thermal shift flashlamp pump slope efficiency threshold power

Characteristics of a multi-component MgO-based bioceramic coating synthesized in-situ by plasma electrolytic oxidation

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Journal of Magnesium and Alloys 2021年第5期9卷 1611-1625页

作者： Nasrinsadat Azarian seyed Mohammad Mousavi Khoei Department of Mining and Metallurgical Engineering Amirkabir University of Technology(Tehran Polytechnic)P.O.Box 15875-4413TehranIran

Plasma electrolytic oxidation(PEO)has held great potential for the advancement of biodegradable implants,as it helps in developing porous bioceramic coatings on the surface of magnesium *** this research work,MgO-based bioceramic coatings containing the Si,P,Ca,Na,and F elements have been successfully fabricated on an AZ31 magnesium alloy plate utilizing the PEO *** characteristic current-voltage behavior of the samples during the process was surveyed in an electrolyte containing Ca(h_(2)PO_(4))_(2),Na_(2)SiO_(3)·9h_(2)O,Na_(3)PO_(4)·12h_(2)O,NaF,and KOh with a ph of 12.5 and electrical conductivity of 20 mS/cm^(-1).The results revealed that applying a voltage of 350-400 V(that is 50-100 V higher than the breakdown limit)could greatly facilitate the synthesis of a PEO ceramic coating with fewer defects and more uniform *** resulting coating was a compositionally graded bioceramic layer with a thickness in the range of 3.5±0.4 to 6.0±0.7µm,comprising the above-mentioned elements as promising bioactive *** synthesized ceramic features were investigated in terms of the elemental distribution of components through the thickness,which indicated a gradual rise in the Si and P contents and,conversely,a decline in the F content towards the outer *** growth mechanism of the PEO coating has been discussed accordingly.

关键词： Az31 magnesium alloy Plasma electrolytic oxidation Bioceramic Coating MgO-based ceramic

Production of γ-Al<sub>2</sub>O<sub>3</sub>from Kaolin

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Open Journal of Physical Chemistry 2011年第2期1卷 23-27页

作者： seyed Ali hosseini Aligholi Niaei Dariush Salari Department of Applied Chemistry Faculty of Chemistry University of Tabriz Tabriz Iran

The paper reports a process for synthesis of γ-alumina from kaolin. Kaolin was transformed to meta-kaolin by calcination at 800oC for 2h. γ-alumina powder was synthesized through extracting alumina from meta- kaolin via h2SO4 and meta-kaolin reactions and consequently precipitation in ethanol, which led to form the aluminum sulfate. The precipitated aluminum sulfate was dried and calcined at 900 oC for 2h, which resulted the formation of γ-alumina. The structure of γ-alumina was confirmed by XRD and FTIR and the mean particles size of γ-alumina was determined by SEM to be 0.5 - 0.9 μm. The study revealed the kaolin could be promising material for preparation of γ-alumina.

关键词： Kaolin γ-Alumina Aluminum Sulfate Calcination

Visible light-induced synthesis of biomass-derived quinoxaline by using Co phthalocyanine immobilized on pyridine-doped g-C_(3)N_(4)

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Journal of Energy Chemistry 2023年第7期82卷 638-652,I0013页

作者： Mingren Jin seyed Mohsen Sadeghzadeh Jinzhu Chen College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 511443GuangdongChina New Materials Technology and Processing Research Center Department of ChemistryNeyshabur BranchIslamic Azad UniversityNeyshaburIran

Visible light-driven valorization of biomass has recently been a pioneering field for nitrogen-containing heterocyclics syntheses due to its sustainable ***,various aromatic ring-doped g-C_(3)N_(4) nanosheets(Ar-g-C_(3)N_(4);Ar=Py,Pm,Ph)were precisely designed to modulate their intrinsic electronic and band structure,which involves pyridine(Py),pyrimidine(Pm),and benzene(Ph)-doped g-C_(3)N_(4).Photocatalysts(CoPc/Ar-g-C_(3)N_(4)) of cobalt(II)phthalocyanine(CoPc)-fabricated Ar-g-C_(3)N_(4) were then developed for oxidative cyclization of furoin with 1,2-phenylenediamines for syntheses of various biomass-derived quinoxalines under visible-light *** catalytic activity(in terms of TOFs)of serial CoPc/Ar-g-C_(3)N_(4) samples increased with their transient photocurrents with CoPc/Py-g-C_(3)N_(4) as the most active *** CoPc/Py-g-C_(3)N_(4),CoPc species functioned as both sensitizer and catalytic sites;while,doped Py led to a narrowed bandgap *** research further demonstrated that O_(2) was activated to superoxide radical(·O_(2)^(-)) by photoexcited high-level-energy electron(hLEE)transfer from Py-g-C_(3)N_(4) to CoPc for the subsequent aerobic oxidation.

关键词： Biomass Functionalized carbon nitride Nitrogen-containing heterocyclics Photocatalysis Quinoxaline

Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

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Chinese Optics Letters 2009年第5期7卷 435-436页

作者： hassan Kaatuzian seyed Iman Taghavi Photonics Research Laboratory Electrical Engineering DepartmentAmirkabir University of Technology

An optical bandwidth analysis of a quantum-well （16 nm） transistor laser with 150-μm cavity length using a charge control model is reported in order to modify the quantum-well location through the base region. At constant bias current, the simulation shows significant enhancement in optical bandwidth due to moving the quantum well in the direction of collector-base junction. No remarkable resonance peak, limiting factor in laser diodes, is observed during this modification in transistor laser structure. The method can be utilized for transistor laser structure design.

关键词： well Simulation of quantum-well slipping effect on optical bandwidth in transistor laser

Laboratory large-scale pullout investigation of a new reinforcement ofcomposite geosynthetic strip

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第5期13卷 1147-1159页

作者： Mehrdad Tajabadipour seyed hamid Lajevardi Department of Civil Engineering Sirjan University of TechnologySirjanIran Department of Civil Engineering Arak BranchIslamic Azad UniversityArakIran

In this paper,more than 70 large-scale pullout tests were performed to evaluate the performance of an innovative composite geosynthetic strip(CGS)reinforcement in sandy *** CGS reinforcement is composed of a geosynthetic strip(GS)and parts of a scrap truck tire as transverse *** experimental pullout results for the CGS reinforcement were compared with the suggested theoretical equations and ordinary reinforcements,including the GS,the steel strip(SS),and the steel strip with rib(SSR).The pullout test results show that adding three transverse members to the GS reinforcement(CGS3)with S/h?6.6(where S and h are the space and height of the transverse members,respectively)increases pullout resistance by more than 120%,170%,and 50%compared to the GS,the SS,and the SSR,*** result shows that the CGS3(CGS with three transverse members)reinforcement needs at least 55.5%,63%,and 33.3%smaller length compared to the GS,the SS,and the SSR,*** general,implementation of mechanically stabilized earth wall(MSEW)with the proposed strip may help geotechnical engineers prevent costly designs and solve the problem of MSEW implementation in cases where there are limitations of space.

关键词： Pullout resistance Composite geosynthetic strip(CGS) Soilegeosynthetic interface Scrap tires Large-scale pullout tests

纳米晶La_(1-x)Eu_xFeO_3的合成、表征及催化甲苯燃烧反应活性(英文)

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催化学报 2011年第9期32卷 1465-1468页

作者： seyed Ali hosseini Mohammad Taghi SADEGhI-SORKhANI Leila KAFI-AhMADI Abdolali ALEMI Aligholi NIAEI Dariush SALARI Department of Applied Chemistry Faculty of Chemistry University of Tabriz Department of Inorganic Chemistry Faculty of Chemistry University of Tabriz

Nanostructured LaFeO3 and substituted La1-xEuxFeO3 (x = 0.1, 0.15, and 0.2) perovskites were synthesized by sol-gel auto-combustion and their activities during the combustion of toluene were evaluated. The structure and physico-chemical properties of the perovskites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and BET surface area analyses. The compounds were crystallized as a perovskite phase with an orthorhombic structure. The mean particle size of the perovskites increased with an increase in europium loading while the specific surface area decreased. Characterization data confirmed that a total insertion of Eu into LaFeO3 occurred at x ≤ 0.15. however, Eu2O3 segregation occurred to some extent especially at x >0.15. The catalytic activity of the catalysts increased substantially with an increase in Eu substitution in the evaluated range.

关键词： perovskite sol-gel europium volatile organic compounds catalytic oxidation