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Synthesis and photoluminescence studies of Ba(Gd,Ln)B_9O_(16):Eu^(3+)(Ln=La,Y) phosphors for n-Uv LED lighting and display devices

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journal of Rare Earths 2015年第2期33卷 140-147页

作者： v.v.Rangari S.j.Dhoble Department of Physics RTM Nagpur University

BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy（SEM） and photoluminescence properties were investigated. The as-synthesized BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd^3＋ by La^3＋ and Y^3＋ ions in the host BaGdB9O16：Eu^3＋ materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba（Gd,Ln）B9O16（Ln=La, Y） phosphors were promising red phosphors, which might find potential applications in near-Uv excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL（compact fluorescent lamp） was also done. Energy transfer mechanism of Gd^3＋ to Eu^3＋ was also discussed in this paper.

关键词： phosphor solid state diffusion display devices photoluminescence rare earths

A review of the effects of dietary organic acids fed to swine

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journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla v A N Suiryanrayna j v Ramana Livestock Research Station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： Chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

Harnessing artificial intelligence for identifying conflicts of interest in research

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World journal of Methodology 2025年第1期15卷 6-8页

作者： Abdulqadir j Nashwan Department of Nursing&Midwifery Research Hamad Medical CorporationDoha 3050Qatar

This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific *** harnessing advanced data analysis,pattern recognition,and natural language processing techniques,AI offers innovative solutions for enhancing transparency and integrity in *** editorial discusses how AI can automatically detect COIs,integrate data from various sources,and streamline reporting processes,thereby maintaining the credibility of scientific findings.

关键词： Artificial intelligence Conflicts of interest Transparency Research integrity Natural language processing

Control systems and data management for high-power laser facilities

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High Power Laser Science and Engineering 2023年第5期11卷 51-75页

作者： Scott Feister Kevin Cassou Stephen dann Andreas Döpp Philippe Gauron Anthony j.Gonsalves Archis joglekar victoria Marshall Olivier Neveu Hans-Peter Schlenvoigt Matthew j.v.Streeter Charlotte A.j.Palmer California State University Channel Islands CamarilloCaliforniaUSA UniversitéParis-Saclay CNRS/IN2P3IJCLabOrsayFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUK Ludwig–Maximilians–Universität München GarchingGermany BELLA Center Lawrence Berkeley National LaboratoryBerkeleyCaliforniaUSA Department of Nuclear Engineering and Radiological Sciences University of MichiganAnn ArborMichiganUSA Ergodic LLC San FranciscoCaliforniaUSA Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Queen’s University Belfast BelfastUK

The next generation of high-power lasers enables repetition of experiments at orders of magnitude higher frequency than what was possible using the prior *** requiring human intervention between laser repetitions need to adapt in order to keep pace with the new laser technology.A distributed networked control system can enable laboratory-wide automation and feedback control *** higher-repetition-rate experiments will create enormous quantities of data.A consistent approach to managing data can increase data accessibility,reduce repetitive data-software development and mitigate poorly organized *** opportunity arises to share knowledge of improvements to control and data infrastructure currently being *** compare platforms and approaches to state-of-the-art control systems and data management at high-power laser facilities,and we illustrate these topics with case studies from our community.

关键词： big data community organization control systems data management feedback loops high-power lasers high repetition rate metadata stabilization standards

Growth and properties of semi-organic nonlinear optical crystal: L-Glutamic acid hydrochloride

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Progress in Natural Science:Materials International 2016年第1期26卷 24-31页

作者： j.Uma v.Rajendran Department of Physics Presidency College

Semiorganic nonlinear optical crystal of L-Glutamic acid hydrochloride（LGHC） was grown from aqueous solution by slow evaporation technique. Single crystal X-ray Diffraction analysis confirms that LGHC crystallizes in orthorhombic system with noncentrosymmetric space group P212121. The powder X-ray diffraction study confirms the crystallinity of the grown crystal. The fundamental functional groups of the grown crystals were analyzed by Fourier Transform Infrared spectroscopic analysis in the range of 450–4000 cm-1. The range of optical transmission was ascertained using Uv–vis–NIR studies. The Refractive Index of the LGHC crystal was found to be 1.4. The second harmonic generation efficiency of the LGHC was determined using Kurtz and Perry powder technique and it was 0.5 times greater than that of the KDP crystal. Thermo Gravimetric Analysis（TGA） and Differential Thermal Analysis（DTA） were used to study thermal behavior of the sample. The dielectric behavior and ac conductivity of the sample were studied as a function of frequency for different temperatures. The mechanical strength of the crystal was determined by vicker's Hardness test. The elastic stiffness constant and yield strength of the sample was calculated.

关键词： Semi organic nonlinear optical crystal X-Ray Diffraction Uv–vis–NIR Dielectric study Microhardness

Performance of inclined pillars with a major discontinuity

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International journal of Mining Science and Technology 2019年第3期29卷 437-443页

作者： K.v.jessu A.j.S.Spearing Western Australia School of Mines Kalgoorlie Curtin University

Discontinuities are an inherent part of the rock mass and majorly affect the stability of the excavation skin and *** dip of the discontinuities and their properties also have a significant effect on the strength of the *** approaches are commonly used to determine the pillar strength but can overestimate the strength and don’t consider the inclination of the pillars and the strength reduction caused by *** modeling is a powerful tool and if calibrated can be used to evaluate the strength of the pillars with discontinuities having a range of *** effect of a discontinuity on inclined pillars was conducted which has been seldom considered in evaluating the pillar ***-dimensional vertical pillars were simulated,and the pillar strength was calibrated to accepted theoretical results and then the discontinuities were introduced in different pillar inclinations with distinct width to height ratios to gain an insight into the effective pillar strength *** upon the results,it was found that the discontinuities have a significant effect with the increase in the inclination of the pillars even at a higher width to height ratios.

关键词： Numerical modelling Pillar Discontinuities Inclination Width to height ratios

Simplicial Indicator Kriging

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journal of China University of Geosciences 2008年第1期19卷 65-71页

作者： R Tolosana-Delgado v Pawlowsky-Glahn j j Egozcue Department of Sedimentology and Environmental Geology Georg-August-Universitt Gttingen D-37077 Gttingen Germany Department of Computer Science and Applied Mathematics University of Girona Girona Spain Department of Applied Mathematics III Universidad Politécnica de Catalunya Barcelona Spain

Indicator kriging （IK） is a spatial interpolation technique devised for estimating a conditional cumulative distribution function at an unsampled location. The result is a discrete approximation, and its corresponding estimated probability density function can be viewed as a composition in the simplex. This fact suggested a compositional approach to IK which, by construction, avoids all its standard drawbacks （negative predictions, not-ordered or larger than one）. Here, a simple algorithm to develop the procedure is presented.

关键词： Aitchison geometry compositional data disjunctive kriging log-ratio approach simplex.

Spectroscopic investigations on Yb^3+ doped and Pr^3+/Yb^3+ codoped tellurite glasses for photonic applications

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journal of Rare Earths 2021年第1期39卷 33-42,I0002页

作者： M.Seshadri M.j.v.Bell v.Anjos Y.Messaddeq Grupo de Engenharia e Espectroscopia de Materiais Departamento de Fisica-ICEUniversidade Federal de Juiz de ForaJuiz de ForaMG36036-900Brazil Centre d'Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalQuebecQCG1V 0A6Canada

In this work we repo rt on structural and spect roscopic properties of Yb^3+doped and Pr^3+/Yb^3+co-doped TeO2-Bi2 O3-ZnO-Li2 O-Nb2 O5(TBZLN)tellurite *** and stretching modes of TeO2 and Te-OH bond(strong and weak)were analysed from the deconvolution of observed Raman and FT-IR *** on the absorption measurements,the energy bands of Yb^3+and Pr^3+ions are *** spectroscopic properties for the radiative transitions of Yb^3+and Pr^3+ions were reported using McCumber and judd-Ofelt *** emission bands originating from 3 P1 and 3 P0 to lower lying levels of Pr^3+were registered under 447 nm *** emission band around 1334 nm assigned to the Pr3:1 G4→3 H5 was observed when excited at 980 *** stimulated emission cross-section(σemi(λ))and effective linewidth(Δλeff)for the 3 P1→3 H6,3 P1→3 H5,3 P0→3 H6,3 P0→3 F2,3 P1→3 F3,3 P1→3 F4,3 P0→3 F4 and 1 G4→3 H5 transitions of Pr^3+are *** luminescence in Pr^3+/Yb^3+codoped glass upon 980 nm excitation was *** resonant transfer processes between Yb^3+and Pr^3+ions are presented and *** chromaticity co-ordinates were also evaluated from the visible emission spectra showing that Pr^3+/Yb^3+co-doped glass may be suitable for the development of yellow-orange(λexc=447 nm)and near white light(λexc=980 nm)emitting devices in photonics.

关键词： Rare earth ions Tellurite glass Spectroscopic properties Upconversion luminescence

The influence of monomer concentration on the optical properties of electrochemically synthesized polypyrrole thin films

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journal of Semiconductors 2013年第10期34卷 13-18页

作者： j.v.Thombare M.C.Rath S.H.Han v.j.Fulari Holography and Material Research Laboratory Department of PhysicsShivaji UniversityKolhapur-416 004India Radiation and Photochemistry Division BARCMumbaiIndia Department of Chemistry Hanyang UniversitySeoulSouth Korea

Polypyrrole （PPy） thin films were deposited on stainless steel and ITO coated glass substrate at a constant deposition potential of 0.8 v versus saturated calomel electrode （SCE） by using the electrochemical polymerization method. The PPy thin films were deposited at room temperature at various monomer concentrations ranging from 0.1 M to 0.3 M pyrrole. The structural and optical properties of the polypyrrole thin films were investigated using an X-ray diffractometer （XRD）, FTIR spectroscopy, scanning electron microscopy （SEM）, and ultravioletvisible （Uv-vis） spectroscopy. The XRD results show that polypyrrole thin films have a semi crystalline structure. Higher monomer concentration results in a slight increase of crystallinity. The polypyrrole thin films deposited at higher monomer concentration exhibit high visible absorbance. The refractive indexes of the polypyrrole thin films are found to be in the range of 1 to 1.3 and vary with monomer concentration as well as wavelength. The extinction coefficient decreases slightly with monomer concentration. The electrochemically synthesized polypyrrole thin film shows optical band gap energy of 2.14 ev.

关键词： polypyrrole electrochemical polymerization method structure optical properties