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Chinese Journal of Chemistry 2011年第11期29卷 2407-2410页

作者： firouzeh, nemati hossein, kiani Department of Chemistry Faculty of Science Semnan University Semnan Iran

A convenient, highly efficient and green approach for synthesis of tetraketones from aromatic aldehydes with dimedone and 1,3-indanedione at room temperature in PEG-400 is described. The use of PEG-400 as the reaction medium and avoiding the use of any catalyst makes the process environmentally benign. Seven new compounds are reported.

关键词： Michael addition green chemistry polyethelene glycol Knoevenagel condensation dimedone,1,3-Indanedione

Zn(NO_3)_2·6H_2O/2,4,6-trichloro-1,3,5-triazine(TCT) a mild and selective system for nitration of phenols

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Chinese Chemical Letters 2010年第4期21卷 403-406页

作者： firouzeh nemati hossein kiani Department of Chemistry Faculty of ScienceSemnan UniversitySemnanIran

Certain phenols and naphthols were nitrated regioselectively with Zn(NO)·6HO/TCT in acetonitrile as solvent at room temperature and short reaction time in good *** reaction condition was *** is a cheap and commercial... 详细信息

关键词： Nitration Phenols 2 4 6-Trichloro-l 3 5-triazine Regioselective

A series of 1,8-dioxooctahydroxanthenes are prepared using trichloroisocyanuric acid

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Chinese Chemical Letters 2009年第11期20卷 1275-1278页

作者： Mohammad A.Bigdeli firouzeh nemati Gholam hossein Mahdavinia Hamideh Doostmohammadi Faculty of Chemistry Tarbiat Moallem University49 Mofateh St.TehranIran Department of Chemistry Faculty of ScienceSemnan UniversitySemnanIran Department of Chemistry Islamic Azad University-Marvdasht BranchMarvdashtIran

A series of aromatic aldehydes are turned in to 3,3,6,6-tetramethy1-9-aryl-1,8-dioxooctahydroxanthene derivatives using trich/oroisocyanuric acid （TCCA） as the catalyst.

关键词： 1,8-Dioxooctahydroxanthenes Trichloroisocyanuric acid Homogenous catalyst 5,5-Dirnethyl-1,3-eyclohexandione

CSRWA:Covert and Severe Attacks Resistant Watermarking Algorithm

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Computers, Materials & Continua 2025年第1期82卷 1027-1047页

作者： Balsam Dhyia Majeed Amir hossein Taherinia Hadi Sadoghi Yazdi Ahad Harati Faculty of Engineering Ferdowsi University of MashhadMashhad***Iran Department of Computer Techniques Engineering Imam Al-Kadhum CollegeBaghdad10087Iraq

Watermarking is embedding visible or invisible data within media to verify its authenticity or protect *** watermark is embedded in significant spatial or frequency features of the media to make it more resistant to intentional or unintentional *** of these features are important perceptual features according to the human visual system(HVS),which means that the embedded watermark should be imperceptible in these ***,both the designers of watermarking algorithms and potential attackers must consider these perceptual features when carrying out their *** two roles will be considered in this paper when designing a robust watermarking algorithm against the most harmful attacks,like volumetric scaling,histogram equalization,and non-conventional watermarking attacks like the Denoising Convolution Neural Network(DnCNN),which must be considered in watermarking algorithm design due to its rising role in the state-of-the-art *** DnCNN is initialized and trained using watermarked image samples created by our proposed Covert and Severe Attacks Resistant Watermarking Algorithm(CSRWA)to prove its *** this algorithm to satisfy the robustness and imperceptibility tradeoff,implementing the Dither Modulation(DM)algorithm is boosted by utilizing the Just Noticeable Distortion(JND)principle to get an improved performance in this ***,luminance,inter and intra-block contrast are used to adjust the JND values.

关键词： Covert attack digital watermarking DnCNN JND perceptual model robustness

Nano-Fe_3O_4 encapsulated-silica particles bearing sulfonic acid groups as a magnetically separable catalyst for green and efficient synthesis of functionalized pyrimido[4,5-b]quinolines and indeno fused pyrido[2,3-d]pyrimidines in water

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Chinese Chemical Letters 2013年第5期24卷 370-372页

作者： firouzeh nemati Raheleh Saeedirad Department of Chemistry Semnan University

The magnetic nanoparticles supported silica sulfuric acid was used as an efficient catalyst for the synthesis of pyrimido[4,5-b]quinoIines and indeno fused pyrido（2,3-d]pyrimidines in *** desired products were obtained in excellent ***_3O_4@SiO_2-SO_3H was readily recovered using an external magnet and could be reused several times without significant loss of reactivity.

关键词： Magnetic nanoparticles Pyrimido[4,5-b]quinolines Indeno fused pyrido[2,3-d]pyrimidines Green solvent

An environmental friendly approach for the catalyst-free synthesis of highly substituted pyrazoles promoted by ultrasonic radiation

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Chinese Chemical Letters 2015年第11期26卷 1397-1399页

作者： firouzeh nemati Seyed Hasan Nikkhah Ali Elhampour Department of Chemistry Semnan University

A cost-effective, highly useful and eco-friendly procedure for the one-pot synthesis of highly substituted pyrazole derivatives has been developed via the reaction of various aldehydes, malononitrile and phenylhydrazine or 4-phenylthiosemicarbazide in PEG-400 and water at room temperature under ultrasound irradiation. Utilization of green solvents without a catalyst makes this methodology very interesting from economic and environmental perspectives. This method provides several advantages such as operational simplicity, use of accessible and economical starting materials and reduced environmental consequences.

关键词： Green chemistryMulticomponent reactionPyrazole Ultrasonic

Estimating oak forest parameters in the western mountains of Iran using satellite-based vegetation indices

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Journal of Forestry Research 2020年第2期31卷 541-552页

作者： Adel Nouri Bahman kiani Mohammad hossein Hakimi Mohammad hossein Mokhtari Department of Forest Sciences Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran Department of Desert Management Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran

Remote sensing is an important tool for studying and modeling forest *** indices obtained from Landsat-8 remotely sensed data were used to estimate the forest parameters in the western mountains of *** sample points were selected on the map of Bayangan County,Kermanshah province,*** each point,a cluster of five rectangular plots of 8100 m2 and 200 m apart was *** clusters were primarily sampled to determine the variance of the forest *** coefficient of variation was used as a criterion for sample *** density,canopy cover and basal area per hectare were calculated for each *** indices were extracted fromthe Landsat-8 images for each *** linear and nonlinear regressions were conducted to develop the *** models were validated using an independent data *** of model parameters was statistically *** results showed that Normalized difference vegetation index(NDVI)and Transformed normalized difference vegetation index(TNDVI)followed by Simple ratio vegetation index(SRVI)were the best predictors,explaining up to 91%of the variations with high *** NDVI,Soil adjusted vegetation index 2(SAVI2)and SRVI,the cubic model was more appropriate than the linear model for predicting the forest *** this model,the R-square value increased while NRMSE decreased *** Infrared percentage vegetation index(IPVI),the quadratic model was better,but,for other vegetation indices,nonlinear models were not superior to linear ***,it can be concluded that Landsat-8 imagery is suitable for predicting forest parameters in the oak forests of western *** course,large plots must be selected,and pre-classification is necessary to gain accurate and precise estimations.

关键词： Basal area Canopy cover Density Landsat-8 Modeling

Seismic assessment of nature-inspired hexagrid lateral load-resisting system

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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 661-672页

作者： Yasaman Memarzadeh kiani Seyed hossein hosseini Lavassani Afshin Meshkat-Dini Department of Civil Engineering Faculty of EngineeringKharazmi UniversityTehranIran

This paper provides a general perspective of the seismic performance of a nature-inspired,honey-comb grid structural system,known as a hexagrid,under near-field ground *** performance of this skeleton is then compared to that of a bundled-tube,as a conventional and efficient load-resisting system in order to provide a better perception of the seismic behavior of a hexagrid *** 20-story buildings with bundled-tube and hexagrid skeleton were *** behavior of the structures was investigated through 3-D finite element computer models and nonlinear time history analyses by subjecting the models to seven three-component records of scaled near-field ground *** of peak inter story drift and corner beam-column joint rotations were calculated and *** indicated that by replacing the exterior columns of the bundled-tube system with inclined beam-column elements of nature-inspired hexagons,lateral stiffness of the building increased and it would tolerate less deformations before global dynamic instability is *** presence of inclined columns in the hexagrid skeleton helped to concentrate local nonlinearities in ring beams rather than exterior columns.

关键词： high-rise steel structure hexagrid structure performance assessment nonlinear seismic analysis

磺酸基修饰的纳米Fe_3O_4包覆二氧化硅颗粒作为可磁分离催化剂高效催化芳香醛与1,3-环二酮的Knoevenagel缩合反应和Michael加成反应(英文)

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催化学报 2012年第11期33卷 1825-1831页

作者： firouzeh nemati Majid M.HERAVI Raheleh SAEEDI RAD Department of Chemistry Semnan UniversitySemnanIran Department of Chemistry School of ScienceAzzahra UniversityVanakTehranIran

Sulfonic acid-functionalized silica-coated nano-Fe3O4 particles(Fe3O4@SiO2-SO3H) have been prepared as a novel heterogeneous acid using a facile *** material was subsequently identified as an efficient catalyst for the synthesis of a variety of tetraketone derivatives via the Knoevenagel condensation and Michael addition reactions of aromatic aldehydes to dimedone,1,3-indanedione,and 1,3-dimethyl barbituric *** catalyst could be readily recovered using a simple external magnet and reused several times without any significant loss in *** current catalytic process is both sustainable and economical because it operates under aqueous conditions,the catalyst can be recovered and reused,and the reactions themselves require only a short time and provide the products in high yield.

关键词： LFCO XRD 化学化学动力学

Stress analysis of thermally affected rotating nanoshafts with varying material properties

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Acta Mechanica Sinica 2016年第5期32卷 813-827页

作者： Keivan kiani Department of Civil Engineering K.N. Toosi University of Technology

Based on the surface elasticity theory of GurtinMurdoch, thermo-elastic fields within rotating nanoshafts with varying material properties subjected to a thermal field are explicitly examined. Accounting for the surface energy effect, the nonclassical boundary conditions are enforced in the cases of fixed-free and free-free conditions. The effects of variation of material properties, temperature of the environment, angular velocity, and radius of the outer radius on the radial displacement, hoop and radial stresses are investigated. In all performed studies, the role of the surface effect on the thermo-elastic field of the nanostructure is methodically discussed.

关键词： Rotating nanoshaft Thermo-elastic field Surface energy effect Non-classical boundary conditions Analytical modeling