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Lanthanide mechanoluminescence

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Journal of Rare Earths 2018年第1期36卷 1-41页

作者： Jean-Claude g.bünzli Ka-Leung Wong Institute of Chemical Sciences and Engineering Swiss Federal Institute of Technology Lausanne (EPFL) CH-1015 Lausanne Switzerland Department of Chemistry Hong Kong Baptist University Kowloon Tong Hong Kong China

Mechanoluminescence （ML） is the emission of light consecutive to a mechanical force or stress imposed to a crystalline material. Many inorganic and organic compounds present this phenomenon that is known for over 400 years. Lanthanide and uranyl salts were among the first substances investigated for this property. Mechanoluminescence, also referred to as triboluminescence, is often considered as being a badly understood phenomenon. In fact it is because of two main reasons. Firstly, a variety of different mechanical stresses, from simple rubbing, to applied pressure, crushing, impact of a weight, ultrasound, laser-generated shock wave, crystallization, dissolution of crystals, or even wind can trigger it. Secondly, ML is very sensitive to the purity and morphology of the sample： in inorganic compounds, generation of traps by doping ＂impurities＂（e.g. lanthanide ions） is responsible for light emission so that the exact composition of the sample has to be known to a very detailed level; for chelates, the crystallization conditions are crucial since they often generate extended networks of weak interactions that are instrumental in triggering ML when they are broken. In fact mechanisms of ML are relatively well known and theories and models often reproduce very well the experiments. Additionally, practical applications are at hand, for example stress, crack, and impact sensors based on SrAI204：Eu11 or Et3NH[Eu（dbm）4] are used to test structures and materials as diverse as road bridges, reinforced concrete elements, pressur- ized containers or airplane wings and to image the propagation of cracks or stress distribution. Military and security applications involve detecting the passage of vehicle or soldiers and producing counter- feiting inks while more joyful applications are luminous balls, wrapping papers and adhesive tapes. Not only bulk materials, but micro- and nanoparticles feature mechanoluminescent properties and single particle manipulation under an AFM allows

关键词： MechanoluminescenceRare earthsStress sensorsPressure sensorsImpact sensors

Farmers'participatory selection of new rice varieties to boost production under temperate agro-ecosystems

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Journal of Integrative Agriculture 2018年第6期17卷 1307-1314页

作者： S Najeeb F A Sheikh g A Parray A b Shikari g zaffar S C Kashyp M A ganie A b Shah Mountain Research Centre for Field Crops KhudwaniAnantnagSher-e-Kashmir University of Agricultural Sciences&Technology of KashmirJammu&Kashmir 192102India Centre for biotechnology Sher-e-Kashmir University of Agricultural Sciences&Technology of KashmirShafimarJammu&Kashmir 191121India Dryland Agriculture Research Station Sher-e-Kashmir University of Agricultural Sciences&Technology of KashmirSrinagarJammu&Kashmir 191111India Assistant Director Education Sher-e-Kashmir University of Agricultural Sciences&Technology of JammuChattaJammu&Kashmir 180009India

In mountain agriculture, early maturity, high grain yield and high biomass are generally considered as farmer preferred traits in rice crop in addition to a multiple set of traits collectively responsible for variety adoption or rejection. The varieties tested only on station evaluation trials without taking the data from the farmers＇ fields by not including farmers as partners for variety evaluation are the reasons of low adoption of varieties. In this regard, a participatory methodology was followed by conducting a number of participatory trials in the farmers＇ fields during 2012-2014 in six districts of Kashmir Valley, India. The mother trials in the farmers＇ fields showed that the test variety SKUA-408 consistently and significantly out yielded Jhelum and farmers＇ variety followed by Shalimar rice 3 （SR3）. The other released varieties like SR1 and SR2 could not perform nicely in the farmers＇ fields because of late maturity. After making the t-test comparison of baby trials （paired plots）, the mean yield superiority of test varieties SKUA-408, SR3, and SKUA-403 over farmers＇ variety during 2013 was around 23, 25, and 22％, respectively, whereas in 2014 the respective yield advantage was recorded as 16.3, 17.7, and 16.2％. In all districts, SKUA-408 and SR3 were significantly preferred by farmers （P〈0.05 or 0.01） in terms of pre-harvest traits namely, tillering ability and general phenotypic acceptability, early maturity and biomass and for post-harvest traits such as general cooking quality besides, the intention to grow the variety for next year. Adoption and dissemination of SKUA-408 began in 2014 from the farm-saved seed in the form of farmer to farmer seed exchange. Farmers are the end users of a variety so the decision by the farmers while judging the variety should be taken into consideration to make the varietal choice more effective for its widespread adoption.

关键词： baby trials farmers' perception farmer preferred traits mother trials mountain agriculture participatory varietal selection variety adoption and popularization

CLASSIFYINg OPTICAL PROPERTIES OF SURFACE-AND bULK-SCATTERINg bIOLOgICAL LAYERS WITH POLARIZATION SINgULAR STATES

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Journal of Innovative Optical Health Sciences 2013年第3期6卷 21-30页

作者： YU.A.USHENKO g.b.bODNAR g.D.KOVAL Correlation Optics Department Chernivtsi National University 2 Kotsyubinsky Str.Chernivtsi 58012Ukraine

The results of singular approach usage in the tasks of description and classification of appearance of optical anisotropy of different types of phase-inhomogeneous biological layers(surface-scattering,optically thin and optically thick)have been *** characteristic values of the fourth Stokes vector parameter(S_(4)=0-linear polarization-(L-state);S_(4)=±1-circular polarization-(C-state))have been chosen as the main analytical tool descni bing polarization-singular *** value of *** been deternined by the value of phase shift betwoen the ort hogonal components of amplitude in the point of biological layer laser image and therefore is azimuthally ***,statistic moments of the first to the fourth orders characterizing the distribution of the amount of characteristic values S4=0;S_(4)=±1 have been used for definition and di ferentiation of optical properties of diferent types of biological layers-surface scattering,optically thin and optically thick human skin.

关键词： Polarization birefringence statistical optics medical and biological imaging

Electro-magneto-hydrodynamic flow of couple stress nanofluids in micro-peristaltic channel with slip and convective conditions

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Applied Mathematics and Mechanics(English Edition) 2021年第4期42卷 593-606页

作者： K.RAMESH M.g.REDDY b.SOUAYEH Department of Mathematics Symbiosis Institute of TechnologySymbiosis International(Deemed University)Pune 412115India Department of Mathematics Acharya Nagarjuna UniversityOngole CampusOngole 523001India Department of Physics College of ScienceKing Faisal UniversityAl-Ahsa 31982Saudi Arabia Laboratory of Fluid Mechanics Physics DepartmentFaculty of Sciences of TunisUniversity of Tunis El ManarTunis 2092Tunisia

This study explores the effects of electro-magneto-hydrodynamics,Hall currents,and convective and slip boundary conditions on the peristaltic propulsion of nanofluids(considered as couple stress nanofluids)through porous symmetric *** phenomena of energy and mass transfer are considered under thermal radiation and heat source/*** governing equations are modeled and non-dimensionalized under appropriate dimensionless *** resulting system is solved numerically with MATHEMATICA(with an in-built function,namely the Runge-Kutta scheme).graphical results are presented for various fluid flow quantities,such as the velocity,the nanoparticle temperature,the nanoparticle concentration,the skin friction,the nanoparticle heat transfer coefficient,the nanoparticle concentration coefficient,and the trapping *** results indicate that the nanoparticle heat transfer coefficient is enhanced for the larger values of thermophoresis ***,an intriguing phenomenon is observed in trapping:the trapped bolus is expanded with an increase in the Hartmann ***,the bolus size decreases with the increasing values of both the Darcy number and the electroosmotic parameter.

关键词： peristalsis magnetohydrodynamics(MHD) nanofluid Hall current porous medium thermal radiation

Study of Temperature Distribution Along an Artificially Polluted Insulator String

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Plasma Science and Technology 2003年第2期5卷 1715-1720页

作者： b Subba Reddy g R Nagabhushana Department of High Voltage Engineering Indian Institute of ScienceDepartment of High Voltage Engineering Indian Institute of Science Bangalore 560012 India Bangalore 560012 India

Insulator becomes wet partially or completely, and the pollution layer on itbecomes conductive, when collecting pollutants for an extended period during dew, light rain, mist,fog or snow melting. Heavy rain is a complicated factor that it may wash away the pollution layerwithout initiating other stages of breakdown or it may bridge the gaps between sheds to promoteflashover. The insulator with a conducting pollution layer being energized, can cause a surfaceleakage current to flow (also temperature-rise). As the surface conductivity is non-uniform, theconducting pollution layer becomes broken by dry bands (at spots of high current density),interrupting the flow of leakage current. Voltage across insulator gets concentrated across drybands, and causes high electric stress and breakdown (dry band arcing). If the resistance of theinsulator surface is sufficiently low, the dry band arcs can be propagated to bridge the terminalscausing flashover. The present paper concerns the evaluation of the temperature distribution alongthe surface of an energized artificially polluted insulator string.

关键词： temperature distribution artificially polluted insulator string

Longitudinal Structure Function FL from Charm Structure Function F2^c

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Communications in Theoretical Physics 2013年第4期59卷 462-466页

作者： b. Rezaei g.R. boroun Physics Department Razi University

We predict the effect of the charm structure function on the longitudinal structure function at small x. In NLO analysis we find that the hard Pomeron behavior gives a good description of FL and Fk^c （k = 2, L） at small x values. We conclude that a direct relation between FL∝ F2^c would provide useful information on how to measure longitudinal structure function at high 0,2 values. Having checked that this model gives a good description of the data, when compared with other models.

关键词： charm structure function gluon distribution quantum chromodynamics small-x

Oscillation of Second Order Nonlinear Delay Damped Difference Equations

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Acta Mathematica Sinica,English Series 2007年第4期23卷 715-722页

作者： S.H.SAKER b.g.ZHANg Department of Mathematics Faculty of ScienceMansoura UniversityMansoura 35516Egypt Department of Mathematics Ocean University of ChinaQingdao 266071P.R.China

Some new oscillation criteria for nonlinear delay difference equation with damping △^2xn＋pn△xn＋F（n,x（n-τ,△x（n-σ）=0,n=0,1,2,…,（＊）are given. Our results partially solve the open problem posed in [Math. bohemica, 125 （2000）, 421- 430]. Also, we will establish some new oscillation criteria for special cases of （＊）, which improve some of the well-known results in the literature.

关键词： oscillation second-order difference equations Riccati techniques

I-Quiz:An Intelligent Assessment Tool for Non-Verbal behaviour Detection

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Computer Systems Science & Engineering 2022年第3期40卷 1007-1021页

作者： b.T.Shobana g.A.Sathish Kumar Department of Information Technology Sri Venkateswara College of EngineeringSriperumbudur602117India Department of Electronics and Communication Engineering Sri Venkateswara College of EngineeringSriperumbudur602117India

Electronic learning(e-learning)has become one of the widely used modes of pedagogy in higher education today due to the convenience and flexibility offered in comparison to traditional learning *** in Information and Communication Technology have eased learner connectivity online and enabled access to an extensive range of learning materials on the World Wide *** covid-19 pandemic,online learning has become the most essential and inevitable medium of learning in primary,secondary and higher *** recent times,Massive Open Online Courses(MOOCs)have transformed the current education strategy by offering a technology-rich and flexible form of online learning.A key component to assess the learner’s progress and effectiveness of online teaching is the Multiple Choice Question(MCQ)assessment in most of the MOOC *** exists on the reliability and validity of the assessment component as it raises a qualm whether the real knowledge acquisition level reflects upon the assessment *** is due to the possibility of random and smart guesses,learners can attempt,as MCQ assessments are more vulnerable than essay type *** paper presents the architecture,development,evaluation of the I-Quiz system,an intelligent assessment tool,which captures and analyses both the implicit and explicit non-verbal behaviour of learner and provides insights about the learner’s real knowledge acquisition *** I-Quiz system uses an innovative way to analyse the learner non-verbal behaviour and trains the agent using machine learning *** intelligent agent in the system evaluates and predicts the real knowledge acquisition level of learners.A total of 500 undergraduate engineering students were asked to attend an on-Screen MCQ assessment test using the I-Quiz system comprising 20 multiple choice questions related to advanced C *** non-verbal behaviour of the learner is recorded using a front-facing camera during t

关键词： E-Learning adaptive and intelligent e-learning systems intelligent tutoring systems emotion recognition non-verbal behaviour knowledge acquisition level

Experimental and ab initio study of ba_(2)Na_(3)(b_(3)O_(6))_(2)F stability in the pressure range of 0–10 gPa

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1846-1854页

作者： Nursultan E.Sagatov Tatyana b.bekker Yulia g.Vinogradova Alexey V.Davydov Ivan V.Podborodnikov Konstantin D.Litasov Sobolev Institute of geology and Mineralogy Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia Department of geology and geophysics Novosibirsk State UniversityNovosibirsk 630090Russia Research and Development Department Novosibirsk State University of ArchitectureDesign and Arts(NSUADA)Novosibirsk 630099Russia Vereshchagin Institute for High Pressure Physics Russian Academy of SciencesTroitsk 108840Russia Fersman Mineralogical Museum Russian Academy of SciencesMoscow 119071Russia

both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate ba_(2)Na_(3)(b_(3)O_(6))_(2)F(P63/m) at pressures up to 10 gPa have been carried out. Electronic-structure calculations with HSE06 hybrid functional showed that ba_(2)Na_(3)(b_(3)O_(6))_(2)F has an indirect band gap of 6.289 eV. A numerical study revealed the decomposition of ba_(2)Na_(3)(b_(3)O_(6))_(2)F into the bab_(2)O_(4),Na bO_(2), and NaF phases above 3.4 gPa at 300 K. Subsequent high-pressure high-temperature experiments performed using ‘Discoverer-1500’DIA-type apparatus at pressures of 3 and 6 gPa and temperature of 1173 K confirmed the stability of ba_(2)Na_(3)(b_(3)O_(6))_(2)F at 3 gPa and its decomposition into bab_(2)O_(4), NabO_(2), and NaF at 6 gPa, which was verified by energy-dispersive X-ray analysis and Raman spectroscopy. The observed Raman bands of the ba_(2)Na_(3)(b_(3)O_(6))_(2)F phase were assigned by comparing the experimental and calculated spectra. The experimental Raman spectra of decomposition reaction products obtained at 6 gPa suggest the origin of a new high-pressure modification of barium metaborate bab_(2)O_(4).

关键词： density functional theory phase stability borate high pressure Raman spectroscopy