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Journal of Rare Earths 2022年第10期40卷 1554-1563页

作者： Ajaz ahmad Wani Amjad Mumtaz Khan Yahiya Kadaf Manea Mansour A.s.salem Department of Chemistry Aligarh Muslim UniversityAMUAligarh202002India

Neodymium-doped Zn-Al layered double hydroxide(Nd/Zn-Al LDH) with excellent photocatalytic activity was prepared by a one-step hydrothermal method. The morphology and physicochemical properties of as-synthesized photocatalysts were well analyzed by Fourier transform infrared(FT-IR), X-ray diffraction(XRD), scanning electron microscopy(sEM), transmission electron microscopy(TEM), photoluminescence(PL), UV-diffuse reflectance spectroscopy(UV-DRs), and Brunauer-Emmett-Teller(BET)surface analysis. Doping Nd^(3+) into Zn-Al LDH enhances the overall catalytic activity of the nanocomposite, like better electron-hole pair separation, increase in interplanar distance, fast electron transfer, and large surface area. The as-prepared nanocomposite shows excellent degradation of three different dyes under visible light irradiation. The degradation efficiency of these dyes follows the order of Congo red > rose Bengal > fast green. Furthermore, liquid chromatography-mass spectrometry(LC-Ms)was employed to propose a possible photocatalytic degradation pathway for Congo Red and Rose Bengal dyes by Nd/Zn-Al LDH. With the help of radical trapping experiments, it is revealed that during the photoexcitation process, the primary reactive intermediates are hydroxyl radicals.

关键词： Organic pollutants Degradation Multifunctional Mesoporous LC-Ms Rare earths

Fate of rubber bush (Calotropis procera (Aiton) W. T. Aiton) in adversary environment modulated by microstructural and functional attributes

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Journal of Arid Land 2023年第5期15卷 578-601页

作者： Ummar IQBAL Mansoor HAMEED Farooq ahmad Muhammad s Aahmad Muhammad AsHRAF Department of Botany the Islamia University of BahawalpurBahawalpurwala 64200Pakistan Department of Botany University of AgricultureFaisalabad 38040Pakistan

Calotropis procera(Aiton)***,belonging to the family Apocynaceae,is C3 evergreen plant species in arid and semi-arid areas of the Punjab Province,*** grows in a variety of habitats like salt affected and waterlogged area,desert/semi-desert,roadside,wasteland,graveyard,forest,crop field,coastline,and river/canal bank.A total of 12 populations growing in different ecological regions were sampled to evaluate their growth,physio-biochemical,and anatomical responses to specific environmental *** adapted to desert/semi-desert showed vigorous growth(plant height,shoot length,and number of leaves),enhanced photosynthetic level(chlorophyll a,chlorophyll b,carotenoids,and total chlorophyll),and apparent anatomical modifications such as increased stem radius,cuticle thickness,storage parenchyma tissues(cortex and pith),and vascular bundles in stems,while the maximum of midrib and lamina thickness,epidermal cells,cuticle thickness,cortical proportion,abaxial stomatal density,and its area in *** was high plasticity in structural and functional features of these populations,which enable them to survive and tolerate under such hot and dry desert *** of saline areas exhibited very critical modifications to sustain under salt prone *** physiological level,it possesses the maximum amount of organic osmolytes(glycine betaine and proline)and antioxidants(superoxide dismutase(sOD),catalase(CAT),and peroxidase(POD)),while at anatomical level,it showed intensive sclerification,large phloem region(inner and outer),pith parenchyma cells,and metaxylem vessels in stems and *** population of dry mountains showed very distinctive features,such as increased shoot ionic contents(K+and Ca2+),collenchyma and sclerenchyma thickness in stems,trichomes size,and numerous small stomata on abaxial surface of *** is concluded that no definite or precise single character can be taken as a yardstick for adjudging the biomass

关键词： Calotropis procera Apocynaceae phenotypic plasticity aridity rubber bush

Finite element model updating for structural damage detection using transmissibility data

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 87-101页

作者： ahmad Izadi Akbar Esfandiari Department of Maritime Engineering Amirkabir University of TechnologyTehran 15875-4413Iran

This paper presents a new finite element model updating method for estimating structural parameters and detecting structural damage location and severity based on the structural responses(output-only data).The method uses the sensitivity relation of transmissibility data through a least-squares algorithm and appropriate normalization of the extracted *** proposed transmissibility-based sensitivity equation produces a more significant number of equations than the sensitivity equations based on the frequency response function(FRF),which can estimate the structural parameters with higher *** abilities of the proposed method are assessed by using numerical data of a two-story two-bay frame model and a plate structure *** evaluating different damage cases,the number,location,and stiffness reduction of the damaged elements and the severity of the simulated damage have been accurately *** reliability and stability of the presented method against measurement and modeling errors are examined using error-contaminated *** parameter estimation results prove the method’s capabilities as an accurate model updating algorithm.

关键词： damage detection model updating output-only transmissibility sensitivity equation

Effect of physiographic factors on qualitative and quantitative charac-teristics of Cornus mas L. natural stands in Arasbaran forests, Iran

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Journal of Forestry Research 2013年第1期24卷 69-74页

作者： ahmad Alijanpour Faculty of Natural Resources Urmia UniversityPardis-e-NazlooSero RoodZip code ***UrmiaI. R. Iran

Arasbaran forests are located in East Azerbaijan （northwest Iran）. Increasing of socio-economic problems in this area causes destruction of biodiversity and structure of these forests. Using multipurpose trees such as cornelian cherry （Cornus mas L） to encourage villagers to produce forest by-products is a basic approach for preserving these forests. This species grows naturally in Arasbaran forests and the fruit is annually exploited using traditional harvest methods. This study aims to assess the ecological requirements of cornelian cherry and the important factors affecting its distribution. For this purpose, 40 circular sampling plots （300 m2） on various slope aspects were demarcated for sampling the occurrence of cornelian cherry in forest stands. DBH and crown cover percentage on north aspects were significantly greater than on other aspects and 4.5% of all trees were cornelian cherry in mature forest stands. North aspects had more seed-origin trees （standards） of cornelian cherry than coppiced trees, while west facing aspects had more coppiced than standard trees. This species had the highest regeneration rate in the sapling stage of 0–2.5 cm DBH. Thus, I recommend cultivation and development of cornelian cherry as a multi-purpose tree in the Arasbaran region on degraded forest lands on north and west aspects.

关键词： Arasbaran forests aspect physiographical factors comelian cherry (Cornus mas L.)

Remediation of sulfidic wastewater by catalytic oxidation with hydrogen peroxide

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Journal of Environmental sciences 2009年第12期21卷 1735-1740页

作者： Naveed ahmad saikat Maitra Binay Kanti Dutta Farooq ahmad Department of Chemical Engineering Universiti Teknologi PETRONAS Department of Chemical Engineering The Petroleum Institute

Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.

关键词： catalytic oxidation wastewater kinetic equation hydrogen peroxide sodium sulfide remediation

Interactive Effects of silicon and Potassium Nitrate in Improving salt Tolerance of Wheat

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Journal of Integrative Agriculture 2014年第9期13卷 1889-1899页

作者： ahmad Bybordi East Azerbaijan Research Center for Agriculture and Natural Resources Tabriz 53555-141 Iran

Adequate regulation of mineral nutrients might be effective to ameliorate the deleterious effects of salts and help to sustain crop productivity, particularly in glycophytes, under salt stress. In this study, laboratory and greenhouse experiments were carried out at Agricultural and Natural Resources Research Centre in East Azerbaijan, Iran, to investigate the interactive effects of silicon and potassium nitrate in alleviating NaCl induced injuries in wheat（Triticum aestivum L.）. In the laboratory experiment, three winter wheat cultivars Pishgam, Afagh and Alvand were grown on sterile filter paper moistened with 20, 40, 60, 80, and 100 mmol L-1 NaCl solution. Results revealed that wheat cultivars were significantly different in their growth response to different concentrations of NaCl and Pishgam was found to be the most tolerant to NaCl stress, and used in the second part of study. In the greenhouse experiment, Pishgam was grown in a hydroponic system subjected to different NaCl levels（20, 60 and 100 mmol L-1） and treated by silicon（0, 2 and 4 mmol L-1, final concentration in nutrient solution using K2siO3） and potassium nitrate（0, 0.5, 1, and 2 mmol L-1, foliar application）. The experimental design was factorial based on a completely randomized design with three replications. It was found that NaCl stress significantly increased proline accumulation and sodium content in the plant tissues while decreased potassium uptake and accumulation by plants. Moreover, plant weight, 100-seed weight, relative water content, chlorophyll content, and photosynthesis were also significantly affected by varying levels of NaCl. However, exogenous application of silicon and potassium nitrate reduced sodium uptake, increased potassium and consequently improved plant weight, 100-seed weight, seed yield, ear length, and photosynthesis rate. This study suggested that utilization of the salt-tolerant cultivar（Pishgam） combined with proper foliar application of potassium nitrate（2 mmol L-

关键词： germination grain yield foliar application photosynthesis proline relative water content

Deep image retrieval using artificial neural network interpolation and indexing based on similarity measurement

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CAAI Transactions on Intelligence Technology 2022年第2期7卷 200-218页

作者： Faiyaz ahmad Department of Computer Engineering Jamia Millia IslamiaNew DelhiIndia

In content-based image retrieval(CBIR),primitive image signatures are critical because they represent the visual *** signatures,which are algorithmically descriptive and accurately recognized visual components,are used to appropriately index and retrieve comparable *** differentiate an image in the category of qualifying contender,feature vectors must have image information's like colour,objects,shape,spatial *** methods such as sketch-based image retrieval by salient contour(sBIR)and greedy learning of deep Boltzmann machine(GDBM)used spatial information to distinguish between image *** requires interest points and also feature analysis emerged image detection ***,a proposed model to overcome this issue and predict the repeating pattern as well as series of pixels that conclude similarity has been *** this study,a technique called CBIR-similarity measure via artificial neural network interpolation(CBIR-sMANN)has been *** collecting datasets,the images are resized then subject to Gaussian filtering in the pre-processing stage,then by permitting them to the Hessian detector,the interesting points are *** on skewness,mean,kurtosis and standard deviation features were extracted then given to ANN for *** results are stored in a database for *** the testing stage,the query image was inputted that is subjected to pre-processing,and feature extraction was then fed to the similarity measurement ***,ANN helps to get similar images from the ***-sMANN have been implemented in the python tool and then evaluated for its *** show that CBIR-sMANN exhibited a high recall value of 78%with a minimum retrieval time of 980 *** showed the supremacy of the proposed model was comparatively greater than the previous ones.

关键词： Gaussian filtering Hessian detector image retrieval interpolation and similarity measurement repeating pattern

Tunable passively Q-switched ytterbium-doped fiber laser with mechanically exfoliated Gase saturable absorber

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Chinese Optics Letters 2018年第2期16卷 93-97页

作者： H.ahmad s.N.Aidit s.I.Ooi Z.C.Tiu Photonics Research Centre University of Malaya

A tunable passively Q-switched ytterbium-doped fiber laser using few-layer gallium selenide（Gase） as a saturable absorber（sA） is *** few-layer Gase sA,which is fabricated by the mechanical exfoliation method,is able to generate a Q-switched fiber laser that has a maximum repetition rate of 92.6 kHz and a minimum pulsed width of 2.3 μ*** highest pulse energy exhibited by the generated pulse is 18.8 nJ with a signal to noise ratio of ~40 *** tunability of the proposed laser covers from 1042 to 1082 nm,giving a tuning range of 40 nm.

关键词： Tunable passively Q-switched ytterbium-doped fiber laser with mechanically exfoliated Gase saturable absorber sA

Evaluation of liquefaction-induced lateral displacement using Bayesian belief networks

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Frontiers of structural and Civil Engineering 2021年第1期15卷 80-98页

作者： Mahmood ahmad Xiao-Wei TANG Jiang-Nan QIU Feezan ahmad state Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Engineering University of Engineering and Technology Peshawar(Bannu Campus)Bannu 28100Pakistan Faculty of Management and Economics Dalian University of TechnologyDalian 116024China Department of Civil Engineering Abasyn UniversityPeshawar 25000Pakistan

Liquefaction-induced lateral displacement is responsible for considerable damage to engineered structures during major ***,an accurate estimation of lateral displacement in liquefaction-prone regions is an essential task for geotechnical experts for sustainable *** paper presents a novel probabilistic framework for evaluating liquefaction-induced lateral displacement using the Bayesian belief network(BBN)approach based on an interpretive structural modeling *** BBN models are trained and tested using a wide-range casehistory records *** two BBN models are proposed to predict lateral displacements for free-face and sloping ground *** predictive performance results of the proposed BBN models are compared with those of frequently used multiple linear regression and genetic programming *** results reveal that the BBN models are able to learn complex relationships between lateral displacement and its influencing factors as cause-effect relationships,with reasonable *** study also presents a sensitivity analysis to evaluate the impacts of input factors on the lateral displacement.

关键词： Bayesian belief network seismically induced soil liquefaction interpretive structural modeling lateral displacement

structure and Thermal Parameters of Ni_(20)Pd_(80) Alloy

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Journal of Materials science & Technology 2009年第2期25卷 208-210页

作者： s. ahmad A.B. Ziya A. Aziz Z.I. Zafar Department of Physics Bahauddin Zakariya University Department of Chemistry Bahauddin Zakariya University

The structure and thermal parameters of Ni20Pd80 alloy were studied by X-ray diffraction（XRD）. The diffraction experiments performed in the temperature range of 308-1100 K revealed that the alloy formed a face centered cubic （fcc） Al-type structure. The temperature dependence of the lattice parameters was investigated by using the Bragg line displacement method showing that the lattice parameter increases with the increase of temperature. The mean linear thermal expansion （MLTE（%））, coefficient of thermal expansion （CTE, α）, the characteristic Debye temperature （（θD） and mean square amplitudes of vibration were determined from XRD data. The value of Debye temperature was found to be 253 K. It was found that temperature factor was independent of the static displacements.

关键词： Alloys structure Thermal parameters X-ray diffraction (XRD)