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Application of g-C_(3)N_(4)/sol-gel nanocomposite on AM60B magnesium alloy and investigation of its properties
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作者 Roghaye Samadianfard Davod Seifzadeh Burak Dikici 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第6期1113-1127,共15页
To protect the AM60B magnesium alloy from corrosion,a sol-gel coating containing hydroxylated g-C_(3)N_(4)nanoplates was applied.The chemical composition of the hydroxylated g-C_(3)N_(4)nanoplates was investigated usi... To protect the AM60B magnesium alloy from corrosion,a sol-gel coating containing hydroxylated g-C_(3)N_(4)nanoplates was applied.The chemical composition of the hydroxylated g-C_(3)N_(4)nanoplates was investigated using X-ray photoelectron spectroscopy(XPS).The hydroxylation process did not affect the crystal size,specific surface area,pore volume,average pore diameter,and thermal stability of the g-C_(3)N_(4)nanoplates.After incorporating pristine and hydroxylated g-C_(3)N_(4)nanoplates,dense sol-gel coatings were obtained.Transmission electron microscopy(TEM)revealed the uniform distribution of the modified g-C_(3)N_(4)in the coating.The average roughness of the coating was also reduced after adding the modified nanoplates due to the decreased aggregation tendency.Electrochemical impedance spectroscopy(EIS)examinations in simulated acid rain revealed a significant improvement in the anticorrosion properties of the sol-gel film after the addition of the modified g-C_(3)N_(4)due to the chemical bonding of the coating to the nanoplates. 展开更多
关键词 Mg alloy corrosion protection SOL-GEL g-C_(3)N_(4)nanocomposite electrochemical impedance spectroscopy
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Assessing the effects of alternative fuel treatments to reduce wildfire exposure
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作者 Roghayeh Jahdi Liliana Del Giudice +4 位作者 Massimo Melis Raff aella Lovreglio Michele Salis Bachisio Arca Pierpaolo Duce 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期373-386,共14页
Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap... Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap was applied to assess the potential of alternative fuel treatments for lowering wildfire losses in a 5,740-ha study area in eastern Sardinia,Italy.Twenty-seven wildfires at 10-m resolution were simulated considering three wind speeds(15,18,and 21 km h-1)to compare fuel treatments:no treatment(NT),irrigated agroforestry areas with shrub clearing(T1),prescribed fire in eucalyptus stands(T2),and irrigated grasslands(T3).The simulations replicated a recent large wildfire that occurred in the study area(Orrìwildfire,2019)and considered the weather and fuel moisture conditions associated with this event.The average wildfire exposure outputs(burned area,probability of burning,conditional flame length,potential crown fire occurrence,and surfaces withflame lengths above 2.5 m)decreased after fuel treatments,compared to no treatment.T1 was the most effective strategy in mitigating wildfire hazards and provided the most significant performance for several wildfire exposure indicators.Treating only 0.5%of the study area(~30 ha)resulted in a decrease in all wildfire exposure metrics to~10%within the study area.In addition,the total surface characterized by high flame length(average>2.5 m)was the lowest in the T1 treatment.This study can help land and fire managers optimize fuel treatment opportunities and wildfire risk mitigation strategies in Mediterranean areas. 展开更多
关键词 Fuel treatment strategies Fire prevention Mediterranean areas Minimum travel time(MTT) Wildfi re exposure
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Fabrication of g-C_(3)N_(4) nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)nanocomposites:Double S-scheme photocatalysts with impressive performance for the removal of antibiotics under visible light
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作者 Nasrin Sedaghati Aziz Habibi-Yangjeh Alireza Khataee 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第7期1363-1374,共12页
Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions... Novel graphitic carbon nitride(g-C_(3)N_(4))nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe)photocatalysts(denoted as GCN-NSh/Bi_(5)O_(7)Br/FeMOF,in which MOF is metal–organic framework)with double S-scheme heterojunctions were synthesized by a facile solvothermal route.The resultant materials were examined by X-ray photoelectron spectrometer(XPS),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),photoluminescence spectroscopy(PL),Fourier transform infrared spectroscopy(FT-IR),UV-Vis diffuse reflection spectroscopy(UV-vis DRS),photocurrent density,electrochemical impedance spectroscopy(EIS),and Brunauer–Emmett–Teller(BET)analyses.After the integration of Fe-MOF with GCN-NSh/Bi_(5)O_(7)Br,the removal constant of tetracycline over the optimal GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite was promoted 33 times compared with that of the pristine GCN.The GCN-NSh/Bi_(5)O_(7)Br/Fe-MOF(15wt%)nanocomposite showed superior photoactivity to azithromycin,metronidazole,and cephalexin removal that was 36.4,20.2,and 14.6 times higher than that of pure GCN,respectively.Radical quenching tests showed that·O_(2)-and h+mainly contributed to the elimination reaction.In addition,the nanocomposite maintained excellent activity after 4 successive cycles.Based on the developed n–n heterojunctions among n-GCN-NSh,n-Bi_(5)O_(7)Br,and n-Fe-MOF semiconductors,the double S-scheme charge transfer mechanism was proposed for the destruction of the selected antibiotics. 展开更多
关键词 g-C_(3)N_(4)nanosheet/Bi_(5)O_(7)Br/NH_(2)-MIL-88B(Fe) metal-organic framework double S-scheme heterojunctions ANTIBIOTICS pho-tocatalytic performance
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Relationship Between Degree of Starch Gelatinization and Quality Attributes of Parboiled Rice During Steaming 被引量:16
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作者 Ebrahim TAGHINEZHAD Mohammad Hadi KHOSHTAGHAZA +2 位作者 Saeid MINAEI Toru SUZUKI Tom BRENNER 《Rice science》 SCIE CSCD 2016年第6期339-344,共6页
Paddy rice samples were parboiled by soaking at 65℃ for 180 min and steaming at 96℃ for 2–10 min,and then dried to achieve the final moisture content of 11% ± 1%. The degree of starch gelatinization (DSG) an... Paddy rice samples were parboiled by soaking at 65℃ for 180 min and steaming at 96℃ for 2–10 min,and then dried to achieve the final moisture content of 11% ± 1%. The degree of starch gelatinization (DSG) andseveral quality attributes (head rice yield (HRY), color value and hardness) of parboiled rice were measured.Results showed that DSG (46.8%–77.9%), color value (18.08–19.04) and hardness (118.6–219.2 N) allincreased following steaming. In contrast, the HRY increased (64.8%–67.1%) for steaming times between 2–4min but decreased (67.1%–65.0%) for steaming times between 4–10 min. Linear relations between DSG andcolor value (R2 = 0.87), and DSG and hardness (R2 = 0.88) were observed. The suitable DSG of parboiled riceleading to the highest HRY was found to be 62.5%, obtained following 4 min of steaming. 展开更多
关键词 parboiling process RICE head rice yield color value HARDNESS degree of starch gelatinization
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Application of novel sol-gel composites on magnesium alloy 被引量:11
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作者 S.Nezamdoust D.Seifzadeh Z.Rajabalizadeh 《Journal of Magnesium and Alloys》 SCIE 2019年第3期419-432,共14页
Application o f defect-free,adherent,and corrosion protective sol-gel film on the magnesium alloys is generally difficult.In this study,two novel sol-gel/conversion coating composites were successfully deposited on AM... Application o f defect-free,adherent,and corrosion protective sol-gel film on the magnesium alloys is generally difficult.In this study,two novel sol-gel/conversion coating composites were successfully deposited on AM60B magnesium alloy in order to provide sufficient protection against the corrosion.The first composite(Ti-Zr/hybrid)was obtained via combination o f a hybrid sol-gel film(synthesized by mixing tetraethoxysilane(TEOS),and 3-glycidyloxypropyl-trimethoxysilane(GPTMS))as outer layer and Ti-Zr conversion coating as primer.Also,the second composite(Ti-Zr/PTMS)was applied in a similar manner by combination o f phenyl-trimethoxysilane(PTMS)so lgel film with the Ti-Zr conversion coating.The morphology and elemental composition of the Ti-Zr conversion film were assessed by the Scanning Electron Microscopy(SEM)and Energy Dispersive X-ray Spectroscopy(EDS),respectively.A cracky conversion film was applied on the alloy surface after immersion in the Ti-Zr conversion coating bath which was mainly composed of MgO,T i02,Zr02,and MgF2 compounds.Uniform,but not-adherent PTMS and hybrid sol-gel films(pure sol-gel films)with obvious defects were directly deposited onto the magnesium alloy without the Ti-Zr pretreatment which were morphologically characterized by the SEM.However,formation o f relatively uniform and completely defect-free Ti-Zr/hybrid and Ti-Zr/PTMS composites after using the Ti-Zr conversion coating as pretreatment was revealed by the SEM observations.In addition,the defects of the Ti-Zr conversion coating were completely filled by the sol-gel layers.The Ti-Zr/PTMS and Ti-Zr/hybrid composite coatings were provided much better corrosion protection capacity than the pure PTMS and hybrid sol-gel films,respectively which was confirmed by the Electrochemical Impedance Spectroscopy(EIS)and Potentiodynamic Polarization(PDP)examinations in 0.05 M NaCl solution. 展开更多
关键词 SOL-GEL COMPOSITE Magnesium alloy CORROSION
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Reciprocal impact of host factors and Helicobacter pylori genotypes on gastric diseases 被引量:5
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作者 Sahar Honarmand-Jahromy Farideh Siavoshi +2 位作者 Reza Malekzadeh Taher Nejad Sattari Saeid Latifi-Navid 《World Journal of Gastroenterology》 SCIE CAS 2015年第31期9317-9327,共11页
AIM: To assess the impact of Helicobacter pylori(H. pylori) genotypes and patient age and sex on the development of gastric diseases.METHODS: H. pylori-infected patients(n = 233) referred to the endoscopy unit at Tehr... AIM: To assess the impact of Helicobacter pylori(H. pylori) genotypes and patient age and sex on the development of gastric diseases.METHODS: H. pylori-infected patients(n = 233) referred to the endoscopy unit at Tehran University of Medical Sciences(Tehran,Iran) were diagnosed with chronic gastritis(CG),gastric ulcer(GU),or duodenal ulcer(DU). Brucella blood agar was used for biopsy cultures and H. pylori isolation under microaerobic conditions. H. pylori isolates were confirmed with biochemical tests and through amplification of the 16 S r RNA gene. DNA was extracted from fresh cultures of the H. pylori isolates and used for amplification of vac A alleles and the cag A gene. Statistical analysis was performed to determine the association between H. pylori genotypes,age(< 40 years vs > 40 years) and sex of the patient,and gastric diseases.RESULTS: CG was the most prevalent gastric disease(113/233; 48.5%),compared to GU(64/233; 27.5%)and DU(56/233; 24%). More patients were male,and gastric diseases were more frequent in patients > 40 years(P < 0.05). The percentage of CG and GU patients that were male and female did not show a significant difference; however DU was more common in males(P < 0.05). Interestingly,a diagnosis of CG in patients > 40 years was more common in females(18.5%) than males(11.6%)(P = 0.05),whereas a diagnosis of GU or DU in patients > 40 years was more frequent in males(14.6% vs 10.7% and 12.4% vs 4.3%,respectively). Overall,genotyping of the H. pylori isolates revealed that the vac A s1(82%),vac A m2(70%),and cag A+(72.5%) alleles were more frequent than vac A s2(18%),vac A m1(29.2%),and cag A-(all P < 0.05). The vac A s1m2 cag A+ genotype was the most prevalent within the three disease groups. vac A s1m2 frequency was 56.2% with a similar occurrence in all diagnoses,while vac A s1m1 appeared more often in DU patients(33.9%). A genotype of vac A s2m2 occurred in 15% of isolates and was more common in CG patients(21.2%); vac A s2m1 was the least common genotype(3%). The vac A s1 allele was found to be a risk factor for DU,vac A s2 for CG,and vac A s1 and vac A s2 for GU(all P < 0.05). The vac A s2m2 genotype was associated with the development of CG and GU compared to DU(P < 0.05). No correlation was found between vac A m or cag A and gastric diseases.CONCLUSION: The outcome of H. pylori infection is the result of interaction between bacterial genotypes and the age and sex of infected individuals. 展开更多
关键词 Age GASTRIC disease GENDER GENOTYPE HELICOBACTER p
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Microwave-Assisted Preparation of CdS Nanoparticles in a Halide-Free Ionic Liquid and Their Photocatalytic Activities 被引量:3
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作者 M.ESMAILI A.HABIBI-YANGJEH 《催化学报》 SCIE CAS CSCD 北大核心 2011年第6期933-938,共6页
A microwave-assisted (4-6 min) method was used for the preparation of CdS nanoparticles in 1-ethyl-3-methylimidazolium ethyl sulfate,a halide-free room-temperature ionic liquid (RTIL).The samples were characterized by... A microwave-assisted (4-6 min) method was used for the preparation of CdS nanoparticles in 1-ethyl-3-methylimidazolium ethyl sulfate,a halide-free room-temperature ionic liquid (RTIL).The samples were characterized by powder X-ray diffraction,energy dispersive X-ray spectroscopy,and scanning electron microscopy.Diffuse reflectance spectra showed a 1.33 eV blue shift relative to bulk CdS.The photocatalytic activities of the nanoparticles for photodegradation of methylene blue (MB) using UV and visible light were measured.The photodegradation of MB decreased with calcination temperature.First order rate constants for the reaction under visible and UV irradiations over the nanoparticles prepared in the RTIL rich media were 5.4 and 2.5 higher,respectively,than the sample prepared in water. 展开更多
关键词 固体超强碱 氧化钙 硝酸钾 氧化铝 氧化锆 氢氧化钾 硝酸钙
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Pushover analysis of asymmetric-plan buildings based on distribution of the combined modal story shear and torsional moment 被引量:3
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作者 Kazem Shakeri Karim Tarbali Mohtasham Mohebbi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第4期707-716,共10页
A pushover procedure with a load pattern based on the height-wise distribution of the combined modal story shear and torsional moment is proposed to estimate the seismic response of 3D asymmetric-plan building frames.... A pushover procedure with a load pattern based on the height-wise distribution of the combined modal story shear and torsional moment is proposed to estimate the seismic response of 3D asymmetric-plan building frames. Contribution of the higher modes and torsional response of asymmetric-plan buildings are incorporated into the proposed load pattern. The proposed pushover method is a single-run procedure, which enables tracing the nonlinear response of the structure during the analysis and averts the elusiveness of conducting multiple pushover analyses. The proposed method has been used to estimate the response of two moment-resisting building frames with 9 and 20 stories. The obtained results indicate the appropriate accuracy and efficiency of the proposed procedure in estimating the trend of the drift profiles of the structures resulted from nonlinear time history analyses. 展开更多
关键词 pushover analysis asymmetric-plan building torsional response story shear torsional moment
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Optimal setting and placement of FACTS devices using strength Pareto multi-objective evolutionary algorithm 被引量:2
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作者 Amin Safari Hossein Shayeghi Mojtaba Bagheri 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期829-839,共11页
This work proposes a novel approach for multi-type optimal placement of flexible AC transmission system(FACTS) devices so as to optimize multi-objective voltage stability problem. The current study discusses a way for... This work proposes a novel approach for multi-type optimal placement of flexible AC transmission system(FACTS) devices so as to optimize multi-objective voltage stability problem. The current study discusses a way for locating and setting of thyristor controlled series capacitor(TCSC) and static var compensator(SVC) using the multi-objective optimization approach named strength pareto multi-objective evolutionary algorithm(SPMOEA). Maximization of the static voltage stability margin(SVSM) and minimizations of real power losses(RPL) and load voltage deviation(LVD) are taken as the goals or three objective functions, when optimally locating multi-type FACTS devices. The performance and effectiveness of the proposed approach has been validated by the simulation results of the IEEE 30-bus and IEEE 118-bus test systems. The proposed approach is compared with non-dominated sorting particle swarm optimization(NSPSO) algorithm. This comparison confirms the usefulness of the multi-objective proposed technique that makes it promising for determination of combinatorial problems of FACTS devices location and setting in large scale power systems. 展开更多
关键词 STRENGTH PARETO multi-objective evolutionary algorithm STATIC var COMPENSATOR (SVC) THYRISTOR controlled series capacitor (TCSC) STATIC voltage stability margin optimal location
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Studying the physiological and yield responses of sunflower inbred lines to full and limited irrigation 被引量:3
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作者 Nasserghadimi Farshad Jahanbakhsh Soodabeh +1 位作者 Ghaffari Mehdi Ebadi Ali 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1605-1611,共7页
In order to study the physiological and yield responses of sunflower inbred lines to full and limited irrigation, an experiment was conducted in the growing season of 2014–2015 in the research field of the Agricultur... In order to study the physiological and yield responses of sunflower inbred lines to full and limited irrigation, an experiment was conducted in the growing season of 2014–2015 in the research field of the Agricultural Research Station in Khoi, Iran. Water withholding was imposed in the flowering stages from R4 (initial flowering) to R6 (full flowering). The results showed that the main effect of irrigation and inbred lines and the interaction effect between irrigation and inbred lines in terms of the proline and protein contents, the catalase, peroxidase, and polyphenol oxidase activities, and seed yield in all inbred lines, and relative water content(RWC) were significant at 1% level. Water withholding in the flowering stage increased the proline content and the catalase, peroxidase, and polyphenol oxidase activities, whereas limited irrigation decreased the protein content and seed yield in all inbred lines and RWC. The lowest protein content and the highest catalase, peroxidase, and polyphenol oxidase activities were observed in BGK 39 under limited irrigation condition, while BGK 37 revealed the highest proline content in such circumstances. The highest seed yield was seen in BGK 1 and BGK 375 in full irrigation condition. Limited irrigation increased the proline content by 49.51%, compared to that of full irrigation condition. 展开更多
关键词 ANTIOXIDANTS CATALASE PEROXIDASE protein RWC
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Photocurrent improvement of an ultra-thin silicon solar cell using the localized surface plasmonic effect of clustering nanoparticles 被引量:2
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作者 F Sobhani H Heidarzadeh H Bahador 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期532-537,共6页
The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar cell.Here we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a clust... The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar cell.Here we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a cluster at the rear side of a thin silicon cell,using the finite difference time domain(FDTD)method.By calculating the optical absorption and hence the photocurrent,it is shown that the clustering of nanoparticles significantly improves them.The photocurrent enhancement is the result of the plasmonic effects of clustering the nanoparticles.For comparison,first a cell with a single nanoparticle at the rear side is evaluated.Then four smaller nanoparticles are put around it to make a cluster.The photocurrents of 20.478 mA/cm2,23.186 mA/cm2,21.427 mA/cm2,and 21.243 mA/cm2 are obtained for the cells using clustering conical,spherical,pyramidal,cylindrical NPs at the backside,respectively.These values are 13.987 mA/cm2,16.901 mA/cm2,16.507 mA/cm2,17.926 mA/cm2 for the cell with one conical,spherical,pyramidal,cylindrical NPs at the backside,respectively.Therefore,clustering can significantly improve the photocurrents.Finally,the distribution of the electric field and the generation rate for the proposed structures are calculated. 展开更多
关键词 clustering nanoparticles plasmonic solar cell localized surface plasmon resonance PHOTOCURRENT finite difference time domain(FDTD)method light management
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Gamma-ray shielding properties of concrete with different percentages of lead 被引量:2
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作者 D.Rezaei-Ochbelagh S.Azimkhani H. Gasemzadeh Mosavinejad 《Nuclear Science and Techniques》 SCIE CAS CSCD 2012年第4期215-218,共4页
In this work,concrete with different percentage leads was used to study gamma-ray shielding properties. The gamma-rays from ^(137)Cs and ^(60)Co sources were detected by Nal(Tl) detector and analyzed by multi-analyzer... In this work,concrete with different percentage leads was used to study gamma-ray shielding properties. The gamma-rays from ^(137)Cs and ^(60)Co sources were detected by Nal(Tl) detector and analyzed by multi-analyzer. Linear attenuation coefficients and compressive strength(kg/cm2) of concrete specimens were conducted.Results show that the concrete at the 90% weight ratio of lead to cement can be suitable for shielding gamma-ray. 展开更多
关键词 混凝土试件 屏蔽性能 γ-射线 射线检测 抗压强度 分析仪 探测器
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On the use of the genetic programming for balanced load distribution in software-defined networks 被引量:3
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作者 Shahram Jamali Amin Badirzadeh Mina Soltani Siapoush 《Digital Communications and Networks》 SCIE 2019年第4期288-296,共9页
As a new networking paradigm,Software-Defined Networking(SDN)enables us to cope with the limitations of traditional networks.SDN uses a controller that has a global view of the network and switch devices which act as ... As a new networking paradigm,Software-Defined Networking(SDN)enables us to cope with the limitations of traditional networks.SDN uses a controller that has a global view of the network and switch devices which act as packet forwarding hardware,known as“OpenFlow switches”.Since load balancing service is essential to distribute workload across servers in data centers,we propose an effective load balancing scheme in SDN,using a genetic programming approach,called Genetic Programming based Load Balancing(GPLB).We formulate the problem to find a path:1)with the best bottleneck switch which has the lowest capacity within bottleneck switches of each path,2)with the shortest path,and 3)requiring the less possible operations.For the purpose of choosing the real-time least loaded path,GPLB immediately calculates the integrated load of paths based on the information that receives from the SDN controller.Hence,in this design,the controller sends the load information of each path to the load balancing algorithm periodically and then the load balancing algorithm returns a least loaded path to the controller.In this paper,we use the Mininet emulator and the OpenDaylight controller to evaluate the effectiveness of the GPLB.The simulative study of the GPLB shows that there is a big improvement in performance metrics and the latency and the jitter are minimized.The GPLB also has the maximum throughput in comparison with related works and has performed better in the heavy traffic situation.The results show that our model stands smartly while not increasing further overhead. 展开更多
关键词 Software-defined networking OpenFlow Mininet OpenDaylight Load balancing
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Corrosion protection and mechanical properties of the electroless Ni-P-MOF nanocomposite coating on AM60B magnesium alloy 被引量:2
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作者 Z.Rajabalizadeh D.Seifzadeh +1 位作者 A.Khodayari Sh.Sohrabnezhad 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第8期2280-2295,共16页
Al-based MIL-53 MOF nanostructure was synthesized hydrothermally and then co-deposited in the electroless nickel coating on AM60B magnesium alloy using Zr pretreatment as an eco-friendly underlayer.The MIL-53(Al)nanos... Al-based MIL-53 MOF nanostructure was synthesized hydrothermally and then co-deposited in the electroless nickel coating on AM60B magnesium alloy using Zr pretreatment as an eco-friendly underlayer.The MIL-53(Al)nanostructure was synthesized in the form of layered semi-cube crystals with the surface area and mean pore diameter of 985.72 m^(2)g^(-1) and 2.00 nm,respectively.The SEM images captured with two various zooming scales from the surface of the plain and MOF containing electroless layers showed cauliflower-like morphology with even distribution of nodule size.Also,the sub-grains of the plain coating disappeared after incorporation of the MOF.Although,both the normal and nanostructure-containing electroless layers have crystalline-amorphous structure,but the nanocomposite coating showed less crystallinity.The average surface roughness of the plain electroless coating was about 309 nm,which decreased to about 222 nm after incorporation of the MOF.The XRD patterns showed that the characteristic peak of Ni broadened after incorporation of the MOF,probably due to the decreasing of the crystallinity.For the heat-treated normal and MOF containing coatings at 200℃ no phase transition takes place,but new peaks appeared for heat-treated coatings at 400℃ due to the crystallization and second-phase precipitation.The results of the EIS tests showed an increase in the amount of the charge transfer resistance(from 19 to 29 kΩcm^(2))after addition of the MOF,which means an improvement in the corrosion resistance.Also,low Jcorrof the composite coating represents its higher corrosion resistance with respect to the plain coating.The micro-hardness values of the composite coating before and after the heat treatment were higher than the plain coating.Also,the Ni-P-MOF coating has a lower wear rate both before and after the heat treatment due to an improvement in its micro-hardness. 展开更多
关键词 Electroless plating MOF Magnesium alloy WEAR EIS
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Accumulation of L-DOPA in various organs of faba bean and influence of drought, nitrogen stress, and processing methods on L-DOPA yield 被引量:2
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作者 Fatemeh Etemadi Masoud Hashemi +2 位作者 Reena Randhir Omid ZandVakili Ali Ebadi 《The Crop Journal》 SCIE CAS CSCD 2018年第4期426-434,共9页
Faba bean(Vicia faba L.)has been identified as a rich source of L-DOPA,which is used in treating Parkinson's disease.Biosynthesis and accumulation of active substances such as L-DOPA in plant tissues may interact ... Faba bean(Vicia faba L.)has been identified as a rich source of L-DOPA,which is used in treating Parkinson's disease.Biosynthesis and accumulation of active substances such as L-DOPA in plant tissues may interact with growing conditions and processing methods.Accumulation trends of L-DOPA in various faba bean organs and the effect of drought stress and N fertilization on L-DOPA content were studied in a field and two greenhouse experiments.The influence of various processing methods on L-DOPA content of faba bean tissues was evaluated.The highest L-DOPA content was detected in fresh leaves(22.4 mg g^(-1))followed by flowers,young pods,mature seeds,and roots.Regardless of processing method,L-DOPA concentration in faba bean tissues was significantly reduced when tissues were boiled or dried.Among various methods of processing,freezing had the lowest detrimental effect,reducing L-DOPA concentrations by 24.1%and 21.1%in leaves and seeds,respectively.Drought stress elevated L-DOPA concentration,and maximum L-DOPA(23.3 mg g^(-1)of biomass)was extracted from plants grown under severe drought stress.However,L-DOPA yield(L-DOPA concentration×biomass)was compromised,owing to the adverse influence of drought stress on dry matter production.No significant difference in L-DOPA concentration was detected among various N application rates. 展开更多
关键词 蚕豆 左旋多巴 植物学 化学分析
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Calculation of thermal neutron albedo for mono-material and bi-material reflectors 被引量:1
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作者 Sara Azimkhani Farhad Zolfagharpour Farhood Ziaie 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第9期185-191,共7页
Thermal neutron albedo has been investigated for different thicknesses of mono-material and bi-material reflectors. An equation has been obtained for a bi-material reflector by considering the neutron diffusion equati... Thermal neutron albedo has been investigated for different thicknesses of mono-material and bi-material reflectors. An equation has been obtained for a bi-material reflector by considering the neutron diffusion equation. The bi-material reflector consists of binary combinations of water, graphite, lead, and polyethylene. An experimental measurement of thermal neutron albedo has also been conducted for mono-material and bi-material reflectors by using a^(241) Am–Be(5.2 Ci) neutron source and a BF3 detector. The maximum value of thermal neutron albedo was obtained for a polyethylene–water combination(0.95 ± 0.02). 展开更多
关键词 NEUTRON current BI-MATERIAL REFLECTOR Thermal NEUTRON ALBEDO BF3 detector Reflection Diffusion equation
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Synthesis, characterization and antimicrobial activity of alkaline ion-exchanged ZnO/bentonite nanocomposites 被引量:1
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作者 Hamideh Pouraboulghasem Mohammad Ghorbanpour +1 位作者 Razieh Shayegh Samaneh Lotfiman 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第4期787-792,共6页
Nanocomposites of zinc/bentonite clay were synthesized for use as an antibacterial material by a quick and simple alkaline ion exchange method. The synthesis of zinc doped bentonite nanocomposite was accomplished by p... Nanocomposites of zinc/bentonite clay were synthesized for use as an antibacterial material by a quick and simple alkaline ion exchange method. The synthesis of zinc doped bentonite nanocomposite was accomplished by placing bentonite in a melting bath of ZnSO_4 for 10, 20, 40, 60 and 90 min. The complexes were characterized by XRD, SEM and DRS. XRD analyses and SEM observations confirmed the diffusion of zinc to the clay surfaces. Antibacterial activity tests against Escherichia coli showed that bentonite did not present any antibacterial properties, but after alkaline ion exchange treatment, inhibition was noted. The highest antibacterial activity was observed with ZnO/bentonite composite alkaline ion exchange for 60 and 90 min. Interestingly, the leaching test indicated that ZnO/bentonite did not present any risk for drinking water treatment. 展开更多
关键词 纳米复合材料 离子交换法 抗菌活性 膨润土 氧化锌 碱性 合成 SEM观察
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Composition and structure of species along altitude gradient in Moghan-Sabalan rangelands,Iran 被引量:1
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作者 sahar ghafari ardavan ghorbani +2 位作者 mehdi moameri raoof mostafazadeh mahmood bidarlord 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1209-1228,共20页
This study provides a checklist of species distributed at the altitude gradient of MoghanSabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of specie... This study provides a checklist of species distributed at the altitude gradient of MoghanSabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of species, Raunkiaer's life forms, geographical distribution, threat and endemicity status, and palatability of species along two altitudinal gradients in the sampling plots, which were conducted in eleven sites/habitats with 300 meters above sea level(masl) altitude intervals(from 100 to 3300 masl). We assessed the plant species composition with special reference to the gradient analysis, and identified overall 396 species, which was comprising 44 families and 194 genera. Results showed that Asteraceae family is by far the most species-rich family, followed by Poaceae, Fabaceae, Caryophyllaceae and Brassicaceae. Among the genera, Astragalus is the most diverse genus, followed by Allium, Veronica and Bromus, Galium, Silene and Ranunculus. Results indicated that the number of species increased as the altitude increased to 1200-1500 masl, but then starts to decline to 3300 masl. Family-to-genera ratio was 1:4.4, the family-tospecies ratio was 1:9, and the genera-to-species ratio was 1:2.04. Growth type of species analysis shows that the frequency of perennial plants was higher in the study area followed by annual species while the lower group was biennial species. The number of annuals showed a decreasing trend towards higher altitude. Hemicryptophytes and therophytes were the most frequent life forms constituted each with(41.9%). Hemicryptophytes showed an increasing trend with altitude, while therophytes showed a decreasing trend with altitude increase, followed by geophytes, chamaephytes, and phanerophytes. Results showed more than half of the species of the study area belonged to Iran-Turanian region and these species showed an increasing trend with altitude. In contrast, Sahara-Sindian species comprise a minor component of the spectrum, with decreasing trend with altitude. The rare and endangered species out of the surveyed taxonomic groups comprised 53 species in total which 29 of them are considered lower risk(LR), 13 data deficient(DD), 5 vulnerable(Vu) and with 3 rare(R) and identified endemic plants comprised 24 species. Some 56.6% species were identified as class III, 22.6% were class I and 20.8% were class II as the palatability variation. Moghan-Sabalan rangelands require strong conservation management policies in case of species loss and changing natural communities due to the occurrence of conversion into cropland, over-grazing and other anthropogenic effects. 展开更多
关键词 植物种类 坡度 牧场 伊朗 结构 生长类型 管理政策 过度放牧
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Spatial variability of soil microbial indices in common alder COMMON ALDER(Alnus glutinosa) stands using a geostatistical approach in northern Iran 被引量:1
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作者 Neda Ghorbanzadeh Ali Salehi +2 位作者 Hassan Pourbabaei Ali Ashraf Soltani Tolarod Seyed Jalil Alavi 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第2期679-688,共10页
Microbial indices and their spatial patterns are strongly affected by environmental factors. Spatial variability of soil properties is one of the most important causes of variability in soil microbial indices. This re... Microbial indices and their spatial patterns are strongly affected by environmental factors. Spatial variability of soil properties is one of the most important causes of variability in soil microbial indices. This research was conducted in the Caspian forest to assess spatial variabilities and frequency distributions of microbial properties.Ninety soil samples were taken using a grid sampling design 40 9 40 m. Microbial indices, organic carbon,nitrogen and pH were determined. Soil variable distributions showed that microbial indices had abnormal distributions. Logarithmic transformation produced normal distribution. Spatial continuity using geostatistical(variogram) was studied and maps obtained by point kriging.The variograms revealed the presence of spatial autocorrelation. The results indicate that spatial dependence of soil microbial indices was affected by non-intrinsic factors and forest management procedures. The maps show that soil microbial indices and soil properties have spatial variability. The spatial pattern of microbial indices was correlated to organic carbon and nitrogen. 展开更多
关键词 VARIOGRAMS Soil MICROBIAL indices Spatial distribution Natural forest Iran
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Combining the 8-hydroxyquinoline intercalated layered double hydroxide film and sol-gel coating for active corrosion protection of the magnesium alloy 被引量:1
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作者 Yahya Jafari Tarzanagh Davod Seifzadeh Roghaye Samadianfard 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第3期536-546,共11页
8-hydroxyquinoline(8-HQ)intercalated layered double hydroxides(LDH)film as underlayer and sol-gel layer was combined for active corrosion protection of the AM60B magnesium alloy.The LDH,LDH/sol-gel,and LDH@HQ/sol-gel ... 8-hydroxyquinoline(8-HQ)intercalated layered double hydroxides(LDH)film as underlayer and sol-gel layer was combined for active corrosion protection of the AM60B magnesium alloy.The LDH,LDH/sol-gel,and LDH@HQ/sol-gel coatings were analyzed using the scanning electron microscopy(SEM),field emission scanning electron microscopy(FESEM),energy dispersive X-ray spectroscopy(EDS),X-ray diffraction(XRD),atomic force microscopy(AFM),and electrochemical impedance spectroscopy(EIS)methods.The SEM images showed that the surface was entirely coated by the LDH film composed of vertically-grown nanosheets.The same morphology was observed for the LDH/sol-gel and LDH@HQ/sol-gel coatings.Also,almost the same topography was observed for both composite coatings except that the LDH@HQ/sol-gel coating had relatively higher surface roughness.Although the LDH film had the same impedance behavior as the alloy sample in 3.5wt%NaCl solution,its corrosion resistance was much higher,which could be due to its barrier properties as well as to the trap-ping of the chloride ions.Similar to the LDH film,the corrosion resistance of the LDH/sol-gel composite diminished with increasing the ex-posure time.However,its values were much higher than that of the LDH film,which was mainly related to the sealing of the solution path-ways.The LDH@HQ/sol-gel composite showed much better anti-corrosion properties than the LDH/sol-gel coating due to the adsorption of the 8-HQ on the damaged areas through the complexation. 展开更多
关键词 magnesium alloy SOL-GEL layered double hydroxides corrosion COATING
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