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crystal structure and luminescence dynamics of highly pure Lim(PO_(3))_(3):Eu^(3+)(m=Sr,ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria m.manhas A.K.Bedyal Ankush Vij H.c.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors Lim(PO_(3))_(3):Eu^(3+)(m=Sr,ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and Lica(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in Lim(PO_(3))_(3):Es^(3+)(m=Sr,ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of Lica(PO_(3))_(3):Eu^(3+)such as commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.y.morassuti A.P.L Silva L.A.O.Nunes S.m.Lima L.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Growth of RB Population in the conversion Phase of chlamydia Life cycle

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communications on Applied mathematics and computation 2024年第1期6卷 90-112页

作者： Frederic y.m.Wan Department of mathematics University of CaliforniaIrvineCA92697-3875USA

Upon infecting a host cell,the reticulate body(RB)form of the chlamydia bacteria simply proliferates by binary fission for an extended *** data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development *** data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 *** modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion ***,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB *** working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.

关键词： chlamydia Life cycle Optimal control maximal infectious spread Specie competitive survival

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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chinese Physics B 2024年第5期33卷 204-211页

作者： y.Lahlou B.maroufi m.Daoud LPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum ***,this indistinguishability is no longer holds for mixed *** contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical *** key ingredient in analyzing quantum correlation in this system is the global covariance *** forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

Optimal coordination of Transportable Power Sources and Repair crews for Service Restoration of Distribution Networks considering Uncertainty of Traffic congestion

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Journal of modern Power Systems and clean Energy 2024年第1期12卷 189-201页

作者： Zhao Shi yan Xu Dunjian Xie Shiwei Xie Amer m.y.m.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(Rcs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and Rcs is proposed,where the TPSs serve as emergency power supply sources,and the Rcs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(mILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

A collocation Technique via Pell-Lucas Polynomials to Solve Fractional Differential Equationmodel for HIV/AIDS with Treatment compartment

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computer modeling in Engineering & Sciences 2024年第10期141卷 281-310页

作者： Gamze yıldırım Suayip yüzbası Department of mathematics Faculty of ScienceAkdeniz UniversityAntalya07058Turkey Department of mathematics Faculty of Basic ScienceGebze Technical UniversityKocaeli41400Turkey Department of mathematics Faculty of ScienceBartın UniversityBartın74100Turkey

In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment *** HIV/AIDS mathematical model with a treatment compartment is divided into five classes,namely,susceptible patients(S),HIV-positive individuals(I),individuals with full-blown AIDS but not receiving ARV treatment(A),individuals being treated(T),and individuals who have changed their sexual habits sufficiently(R).According to the method,by utilizing the PLPs and the collocation points,we convert the fractional order HIV/AIDS epidemic model with a treatment compartment into a nonlinear system of the algebraic ***,the error analysis is presented for the Pell-Lucas approximation *** aim of this study is to observe the behavior of five populations after 200 days when drug treatment is applied to HIV-infectious and full-blown AIDS *** demonstrate the usefulness of this method,the applications are made on the numerical example with the help of *** addition,four cases of the fractional order derivative(p=1,p=0.95,p=0.9,p=0.85)are examined in the range[0,200].Owing to applications,we figured out that the outcomes have quite decent ***,we understand that the errors decrease when the value of N *** figures in this study are created in *** outcomes indicate that the presented method is reasonably sufficient and correct.

关键词： collocation method fractional differential equations HIV/AIDS epidemic model Pell-Lucas polynomials

Supposition of graphene stacks to estimate the contact resistance and conductivity of nanocomposites

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 663-676页

作者： y.ZARE m.T.mUNIR G.J.WENG K.y.RHEE Biomaterials and Tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran college of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait Department of mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study,the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity of samples are evaluated with developed equations superior to those previously *** contact resistance and nanocomposite conductivity are modeled by several influencing factors,including stack properties,interphase depth,tunneling size,and contact *** developed model's accuracy is verified through numerous experimental *** further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity are ***,the contact resistance is primarily dependent on the polymer tunnel resistivity,contact area,and tunneling *** dimensions of the graphene nanosheets significantly influence the conductivity,which ranges from 0 S/m to90 S/*** increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's ***,the thicker interphase and smaller tunneling size can lead to higher sample conductivity due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene polymer composite stacked nanosheet tunneling conductivity contact resistance interphase

consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz c.c.m.van de Wiel L.A.P.Lotz m.J.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency Plant products

mechanisms behind the environmental sensitivity of carbon fiber reinforced polytetrafluoroethylene(PTFE)

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Friction 2024年第5期12卷 997-1015页

作者： Pontus JOHANSSON P.mARKLUND m.BJORLING y.SHI Division of machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

carbon fiber reinforced polytetrafluoroethylene (cF/PTFE) composites are known for their exceptional tribological performance when sliding against steel or cast iron in inert gas environments. compared to experiments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been reported for tests conducted in dry nitrogen and hydrogen. moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a possible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have pointed out the environmental sensitivity of cF/PTFE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of cF/PTFE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. climate-controlled three-pin-on-disc experiments were conducted in nitrogen atmospheres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more pronounced for oxygen than moisture. A qualitative method was developed to estimate the tribofilm coverage on the cF/PTFE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. moreover, a loosely adhered tribofilm was observed on top of the cF/PTFE surface in presence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may explain the lower coefficient of friction in presence of moisture compared to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： polymer composite tribofilm tribochemistry atmosphere