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Information Processing in Agriculture 2020年第3期7卷 375-383页

作者： ali m.ali S.m.Ibrahim Bijay-Singh Department of Soil Fertility and microbiology Desert Research CenterCairo 11753Egypt Department of Soil Science Punjab Agricultural UniversityLudhiana 141004India

Rapid acquisition of information about nitrogen(N)uptake and grain yield is an essential step in making site-specific in-season fertilizer N management *** objective of this study was to quantify and validate the relationships between N uptake and grain yield of wheat using in-season measurements with atLeaf chlorophyll meter and GreenSeeker optical sensor at Feekes 6 growth stage(jointing stage)of *** relationships were developed using data generated from experiments with multi-rate fertilizer N treatments and conducted in two consecutive wheat seasons(2017/2018 and 2018/2019)at two locations in the western Nile Delta of Egypt.A power function based on atLeaf measurement at Feekes 6 stage of wheat could explain 55.3%and 53.3%variations in the N uptake at this stage and grain yield at maturity,*** with GreenSeeker were related with N uptake and yield of wheat through exponential function and could explain 68.5%and 60.6%of the variation in N uptake and grain yield,*** developed models were validated on an independent data set from another field experiment on *** normalized root mean square error for the relation between atLeaf measurements and N uptake and grain yield were fair,whereas the fits were good for measurements with *** study reveals that atLeaf chlorophyll meter and GreenSeeker optical sensor can be successfully used for establishing site-specific N management strategies in wheat.

关键词： N uptake Grain yield Wheat atLeaf sensor GreenSeeker sensor

Photocatalytic Synthesis of Gold Nanoparticles Using Preyssler Acid and Their Photocatalytic Activity

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催化学报 2011年第6期32卷 978-982页

作者： ali AYATI ali AhmADPOUR Fatemeh F.BAmOhARRAm majid m.hERAVI hamed RAShIDI Department of Chemical Engineering Ferdowsi University of Mashhad Department of Chemistry School of SciencesIslamic Azad University Department of Chemistry School of SciencesAlzahra University

Preyssler acid h14[NaP5W30O110] was used as reducing agent and stabilizer for the synthesis of gold nanoparticles by photolysis of Au(III)/Preyssler acid/propan-2-ol *** acid plays both the role of transferring electrons from propan-2-ol to Au(III) and stabilizing the ***-2-ol was used as sacrificial reagent for the photoformation of reduced Preyssler *** nanoparticles (Au NPs) were characterized by UV-Vis spectroscopy,transmission electron microscopy (TEm),and particle size distribution (PSD) *** synthesized Au NPs had a uniform hexagonal morphology and their size was about 17 *** catalytic performance of these NPs for photodegradation of methyl orange (meO) was investigated in aqueous ***-Vis studies showed that Au NPs can catalyze photodegradation of this azo *** pseudo-first-order rate constants were also calculated for this reaction.

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

machine Learning Approach for COVID-19 Detection on Twitter

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Computers, materials & Continua 2021年第8期68卷 2231-2247页

作者： Samina Amin m.Irfan Uddin heyam h.Al-Baity m.ali Zeb m.Abrar Khan Institute of Computing Kohat University of Science and TechnologyKohat26000Pakistan Department of Information Technology College of Computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia

Social networking services(SNSs)provide massive data that can be a very influential source of information during pandemic *** study shows that social media analysis can be used as a crisis detector(e.g.,understanding the sentiment of social media users regarding various pandemic outbreaks).The novel Coronavirus Disease-19(COVID-19),commonly known as coronavirus,has affected everyone worldwide in *** Twitter data have revealed the status of the COVID-19 outbreak in the most affected *** study focuses on identifying COVID-19 patients using tweets without requiring medical records to find the COVID-19 pandemic in Twitter messages(tweets).For this purpose,we propose herein an intelligent model using traditional machine learning-based approaches,such as support vector machine(SVm),logistic regression(LR),naïve Bayes(NB),random forest(RF),and decision tree(DT)with the help of the term frequency inverse document frequency(TF-IDF)to detect the COVID-19 pandemic in Twitter *** proposed intelligent traditional machine learning-based model classifies Twitter messages into four categories,namely,confirmed deaths,recovered,and *** the experimental analysis,the tweet data on the COVID-19 pandemic are analyzed to evaluate the results of traditional machine learning approaches.A benchmark dataset for COVID-19 on Twitter messages is developed and can be used for future research *** experiments show that the results of the proposed approach are promising in detecting the COVID-19 pandemic in Twitter messages with overall accuracy,precision,recall,and F1 score between 70%and 80%and the confusion matrix for machine learning approaches(i.e.,SVm,NB,LR,RF,and DT)with the TF-IDF feature extraction technique.

关键词： Artificial intelligence coronavirus COVID-19 pandemic social network Twitter machine learning natural language processing

Thermo-optic characterization of KDP single crystals by a modified Snarmont setup for electro-optic modulation system

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Chinese Optics Letters 2009年第7期7卷 632-639页

作者： h. L. Saadon m. A. Rahma ali F. marhoon N. Thofanous m. Aillerie Department of Informatics and Telecommunications Optoelectronics Group University of AthensPanepistimiopolis Ilisia GR-157 84 Athens Greece Department of Physics College of Science University of BasrahBasrah Iraq Laboratoire matriaux Optiques Photonique et Systmes UMR CNRS 7132 Universit de Metz et Suplec2 rue E. Belin 57070 Metz France

For our KDP crystal orientation, various tbermo-optic （TO） and relevant temperature-dependence param- eters are defined, presented, and studied in the framework of a transverse and a longitudinal electro-optic （EO） modulation systems. This study is based on the concept of the so-called opto-electrical bias （~） ap- plied to the system. For both of the above EO-modulation systems, a set of original equations is extracted and investigated with regard to each of the more important TO or temperature coefficients. Using these equations, for these parameters the role of the transverse configuration is examined in comparison with its corresponding longitudinal configuration. A comparison is done with other orientation of the same KDP crystal.

关键词： narmont setup for electro-optic modulation system Thermo-optic characterization of KDP single crystals by a modified S KDP

microstructures in a carburized steel after isothermal pearlitic treatment

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journal of materials Science & Technology 2023年第29期160卷 66-75页

作者： j.Abraham mathews h.Farahani j.Sietsma R.h.Petrov m.G.mecozzi m.j.Santofimia Department of materials Science and Engineering Delft University of TechnologyMekelweg 22628 CDDelftThe Netherlands Tata Steel Research&Development IJmuidenThe Netherlands Department of Electromechanical Systems and Metal EngineeringGhent UniversityTech Lane Ghent Science park-Campus A ZwijnaardeTechnologiepark 46Belgium

The influence of carbon concentration variations on pearlite formation(20 h at 600℃)in a case-carburized steel is *** resultant microstructure shows three distinct regions:carburized case,a transition region,and the original *** microstructural transition from the case to the core regions is observed to be relatively *** investigated region of the carburized case(0.9 wt.%C)con-tains two types of pearlite:ferrite+cementite and ferrite+m_(23)C_(6),where the pearlitic aggregate with m_(23)C_(6)shows faster formation *** kinetics of pearlite formation in the transition region(0.3 wt.%C)is very slow and is observed with only m_(23)C_(6)*** around 40%austenite decomposes into pearlite in the transition region,which,in comparison to the carburized case region of 0.9 wt.%C is a fraction that is lower by a factor of *** is absent in the investigated core region(0.16 wt.%C).The microstructure in this region is predominantly martensite and pro-eutectoid ferrite,with a fraction of ferrite well below the equilibrium *** formation in this region is limited by the redistribution of mainly Ni,mn,and Cr,and their resulting solute drag effect on the austenite/ferrite interface.A ther-modynamic and kinetic argumentation of these observations is provided with the help of thermodynamic data,precipitation simulations,and a general mixed-mode Gibbs energy balance model.

关键词： Pearlite formation Carburized steel m 2_(3)C_(6)carbide Kinetics Solute drag

manipulation of Crawling Growth for the Formation of Sub-millimeter Long ZnO Nanowalls

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journal of materials Science & Technology 2008年第4期24卷 589-593页

作者： h.j.FAN m.Zacharias Department of Earth Sciences University of Cambridge U.K. Faculty of Applied Science Albert-Ludwigs-University Freiburg Germany Formerly at： max Planck Institute of microstructure Physics Halle Germany

Vapor-phase growth of ZnO nanowires based on gold catalyst is usually accompanied with lateral crawling growth on the substrate surface. We present results from our systematic experiments where the growth temperature and catalyst size are controlled. The data corroborate that it is possible to obtain clean vertical nanowire arrays while avoiding the crawling growth. 0% the other hand, crawling growth can be manipulated to obtain root-interconnected nanowire arrays, which could be useful for certain applications. Our results also imply that the previously suggested growth mechanism for the wire-on-wall hybridstructure might be incorrect. Finally, we show the formation of sub-millimeter long, straight ZnO nanowalls by combining a gold-catalyzed epitaxial growth of vertical nanowires and their mergence due to a confined crawling growth. These unconventional nanostructures might have unique electric or optical transport properties.

关键词： Nanowire Nanowall ZnO Crawling growth

Effect of interlayer addition on microstructure and mechanical properties of NiTi/stainless steel joint by electron beam welding

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journal of materials Science & Technology 2021年第2期61卷 16-24页

作者： h.Niu h.C.jiang m.j.Zhao L.j.Rong CAS Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of ScienceShenyang110016China School of materials Science and Engineering University of Science and Technology of ChinaHefei230026China

NiTi/Stainless Steel(SS) sheets have been welded via a vacuum electron beam welding process, with three methods(offsetting electron beam to SS side without interlayer, adding Ni interlayer and adding Fe Ni interlayer), to promote mechanical properties of the Ni Ti/SS joints. The joints with different interlayers are all fractured in the weld zone near the Ni Ti side, which is attributed to the enrichment of intermetallic compounds including Fe2 Ti and Ni3 Ti. The fracture mechanisms of different joints are strongly dependent on the types of interlayers, and the joints without interlayer, adding Ni interlayer and adding Fe Ni interlayer exhibit cleavage fracture, intergranular fracture and mixed fracture composed of cleavage and tearing ridge, respectively. Compared with the brittle laves phase Fe2 Ti, Ni3 Ti phase can exhibit certain plasticity, block the crack propagation and change the direction of crack propagation. The composite structure of Ni3 Ti and Fe2 Ti will be formed when the Fe Ni alloy is taken as the interlayer, which provides the joint excellent mechanical properties, with rupture strength of 343 mPa.

关键词： NiTi Stainless steel Electron beam welding Interlayer mechanical property

Biological transformation,kinetics and dose-response assessments of bound musk ketone hemoglobin adducts in rainbow trout as biomarkers of environmental exposure

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journal of Environmental Sciences 2008年第7期20卷 878-884页

作者： m A mottaleb j h Zimmerman T W moy Department of Chemistry and Biochemistry Baylor UniversityP.O.Box 97348WacoTX 76798USA. U.S.Environmental Protection Agency National Exposure Research LaboratoryEnvironmental Sciences Division944 East Harmon AveLas VegasNV 89119USA

Low levels (ng/g) of musk ketone (mK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other ***,aquatic organisms can be continuously exposed to *** this study,kinetics and dose-response assessments of 2-amino-mK (AmK) metabolite,bound to cysteine-hemoglobin (hb) in rainbow trout,formed by enzymatic nitro-reduction of mK have been *** were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg mK/g ***...

关键词： biotransformation kinetics hemoglobin adducts dose-response nitro musks biomarker fish

The Fine Spectra of the Difference Operator △ Over the Sequence Space bv_p,(1≤p<∞)

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Acta mathematica Sinica,English Series 2007年第10期23卷 1757-1768页

作者： ali m.AKhmEDOV Feyzi BASAR Baku State University Department of Mech.& Math.Z.Khalilov Str.23P.O.Box 370145BakuAzerbaijan nOnü Universitesi Eitim FakültesiMatematik Eitimi BOlümüMalatya-44280

The sequence space bvp consisting of all sequences （xk） such that （xk -xk-1） belongs to the space gp has recently been introduced by Basar and Altay [Ukrainian math. j., 55（1）, 136-147（2003）]; where 1 ≤ p ≤ ∞. In the present paper, some results concerning with the continuous dual and f-dual, and the AD-property of the sequence space bvp have been given and the norm of the difference operator A acting on the sequence space bvp has been found. The fine spectrum with respect to the Goldberg＇s classification of the difference operator △ over the sequence space bvp has been determined, where 1≤p〈∞.

关键词： spectrum of an operator difference operator the continuous dual and f-dual of a sequence space the AD-property and the sequence space bvp

Removal of organic pollutants by lanthanide-doped mIL-53(Fe) metal-organic frameworks:Effect of dopant type in magnetite precursor

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journal of Rare Earths 2023年第1期41卷 140-148页

作者： Shimaa m.ali Khadija m.Emran Fedaa m.m.Alrashedee Department of Chemistry Faculty of ScienceCairo University.Giza12613Egypt Department of Chemistry Faculty of ScienceTaibah UniversityMadinah30002Saudi Arabia

A series of undoped and lanthanide doped mIL-53(Fe)/Ln-Fe_(3)O_(4)(Ln=La,Nd,or Gd) metal-organic frameworks(mOFs) were prepared by the solvothermal *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),Brunauer-Emmett-Teller(BET) measurements,scanning electron microscopy(SEm),and thermal *** and FT-IR results ascertain the successful mOF formation for all prepared ***-53(Fe)/La-Fe_(3)O_(4) has the smallest particle size of 8.6 nm,the largest BET surface area of 54.2 m^(2)/g,and the highest *** and different lanthanide doped mIL-53(Fe) we re employed as sorbents for the removal of methylene blue(mB)dye from aqueous solutions to examine the doping benefit and the effect of the dopant size on the sorption *** causes mOFs to act as ph-independent sorbents,which make it applicable at any *** follows pseudo-second-order kinetic model,and doped sorbents attain equilibrium *** isotherms are followed,except for mIL-53(Fe)/La-Fe_(3)O_(4).The adsorption capacity increases with increasing the dopant ion size,100.5 mg/g for La-doped mOF,which is about four times higher than that of undoped *** adsorption mechanism involves chemical interactions between Lewis acid in magnetite mIL-53(Fe) series and Lewis base in mB.

关键词： Lanthanide metal organic framework Adsorption Doping Organic dyes Rare earths