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Phosphor
Terms modified by Phosphor Selected AbstractsBiological Templating: Bioinspired Design of SrAl2O4:Eu2+ Phosphor (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 4 2009Mater. The morphology of native pine wood is replicated to generate a novel cellular phosphor material based on Eu-doped strontium aluminate. On page 599, the authors describe the infiltration and conversion of the original cell wall pattern using the biotemplating technique. The obtained materials show a strong green photoluminescence. Biological templates offer a novel approach for designing advanced micropatterned phosphor materials. [source] Bioinspired Design of SrAl2O4:Eu2+ PhosphorADVANCED FUNCTIONAL MATERIALS, Issue 4 2009Mariya H. Kostova Abstract A phosphor based on Sr0.97Al2O4:Eu0.03 with a biomorphous morphology is manufactured via vacuum assisted infiltration of wood tissue (Pinus sylvestris) with a precursor nitrate solution. The nitrate solution penetrates homogeneously into the uniform arrangement of rectangular shaped tracheidal cells of the wood tissue. According to scanning electron microscopy, the original wood cell walls are completely transformed retaining the original wood structure. The major crystalline phase is monoclinic SrAl2O4, detected by X-ray diffraction and confirmed by Rietveld refinement. Energy-dispersive X-ray analysis proves the homogeneous conversion of the original wood cell wall into Sr0.97Al2O4:Eu0.03 struts. The optical properties of the resulting phosphor material are determined by photoluminescence and cathode-luminescence spectroscopy in scanning electron microscopy. The biotemplated Sr0.97Al2O4:Eu0.03 shows a characteristic green emission at 530,nm (2.34,eV). Shaping biomorphous SrAl2O4:Eu2+ phosphor with a microstructure pseudomorphous to the bioorganic template anatomy offers a novel approach for designing micropatterned phosphor materials. [source] A Novel Narrow Band Red-Emitting Phosphor for White Light Emitting DiodesINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 4 2009Sivakumar Vaidyanathan Research on down conversion phosphor materials is the key for the development of solid-state lighting (SSL). Especially finding alternative red phosphor for white light emitting diodes (LEDs) based on blue or near ultraviolet (NUV) LEDs is important research task. In this view, we have synthesized a series of Eu3+ -substituted La2W2,xMoxO9 (x=0,2, in step of 0.3) red phosphor and characterized by X-ray diffraction (XRD) and photoluminescence. XRD results reveal a phase transition from triclinic to cubic structure for x>0.2. All the compositions show broad charge transfer (CT) band due to CT from oxygen to tungsten/molybdenum and red emission due to Eu3+ ions. Select compositions show high red emission intensity compared with the commercial red phosphor under NUV/blue ray excitation. Hence, this candidate can be a possible red phosphor for white LEDs. [source] Response of Black Nightshade (Solanum nigrum L.) to Phosphorus ApplicationJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2000M. M. A. Khan A pot experiment was conducted to study the effect of phosphorus (P) on the vegetative and reproductive growth of black nightshade (Solanum nigrum L.). Single superphosphate was applied at 0, 0.15, 0.30, 0.45, 0.60 and 0.75 g P/pot containing 3.5 kg of soil. Seeds were sown directly in pots and plant samples were taken at fortnightly intervals for recording growth and yield parameters. In addition, the solasodine content in fruit and N, P and K levels in leaves were also estimated. Most parameters were significantly influenced by P, with0.45 g/pot generally proving optimal. The data also established that the berries should be harvested between 160 and 190 days (days after sowing), preferably at 175 days for maximum fruit yield and solasodine production. Most parameters showed consistent and positive correlations with leaf P content. Interestingly, the correlation between leaf P content at 40 days and solasodine yield at 175 days was highly significant (r = 0.888), implying that the former is predictive of the latter. Thus, if low leaf P content was noted at 40 days corrective measures like foliar application or top dressing may be adopted to increase the leaf P content to ensure maximum solasodine at harvest. Zusammenfassung Es wurde ein Gefäßexperiment mit Nachtschatten (Solanum nigrum L.) durchgeführt, um den Einfluß von Phosphor (P) auf das vegetative und reproduktive Wachstum zu untersuchen. Einfach-Superphosphat wurde mit Mengen von 0, 0,15, 0,30, 0,45, 0,60 und 0,75 gP/Gefäß mit 3,5 kg Boden angewendet. Die Samen wurden direkt in die Gefäße ausgesät und die Pflanzenproben wurden 14-tägig für Untersuchungen hinsichtlich Wachstum und Ertragsparameter genommen. Zusätzlich wurde der Solasodine-Gehalt in der Frucht sowie N, P und K in den Blättern bestimmt. Die meisten Parameter waren sig-nifikant beeinflußt durch P, wobei sich 0,45 g/Gefäß als optimal erwies. Die Ergebnisse zeigen, daß die Beeren 160,190 d (Tage nach der Aussaat), am günstigsten 175 Tage, für maximalen Fruchtertrag und Solasodine-Produktion zu ernten sind. Die meisten Parameter zeigten konsistente und positive Korrelationen mit dem Blatt-P-Gehalt. Es ist interessant, daß die Korrelation zwischen Blatt-P-Gehalt nach 40 Tagen sowie Solasodine-Ertrag nach 175 Tagen hochsignifikant war (r = 0,888), was für eine Zeitvoraussage genutzt werden kann. Es erscheint daher möglich, falls geringer Blatt-P-Gehalt nach 40 Tagen festgestellt wird, Blattanwendungen oder Düngungen zur Erhöhung des Blatt-P-Gehaltes vorzunehmen, um ein Maximum an Solasodine zur Ernte zu erreichen. [source] Uptake of residual phosphate and freshly applied diammonium phosphate by Lolium perenne and Trifolium repens,JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 5 2003Anne Gallet Abstract Residual fertilizer phosphorus (residual P) may significantly contribute to crop P nutrition. To test this hypothesis, a pot experiment was conducted with ryegrass (Lolium perenne) and clover (Trifolium repens) grown separately on three different soils which either had not received P fertilizer for at least nine years (0F) or had received P fertilizer equivalent to crop P off-take (F). Soils in the pot experiment were given either none (0F, F) or a single rate of 15 mg P (kg soil),1 as diammonium phosphate (0F+DAP, F+DAP). In the treatments 0F+DAP and F+DAP DAP had been labeled with 33PO4 while in the treatments 0F and F the pool of available soil P had been labeled with carrier-free 33PO4. This allowed estimating the quantities of P in plant dry matter that derived from native soil P, residual fertilizer P or fresh fertilizer P. Fourteen to 62,% of the P in the above ground biomass of white clover or perennial ryegrass were derived from residual P whereas 7 to 28,% were derived from freshly applied DAP. The proportion of P derived from residual P was correlated to the total amount of P fertilizer added to the soils, while the proportion of P derived from DAP was correlated to the concentration of P in the soil solution of the 0F and F soils. Aufnahme von Phosphat aus Rückständen von früherer Düngung und aus frisch ausgebrachtem Diammoniumphosphat durch Lolium perenneund Trifolium repens In Düngerrückständen enthaltener Phosphor (P) kann möglicherweise signifikant zur P-Ernährung von Kulturpflanzen beitragen. Um diese Hypothese zu prüfen, wurde im Topfversuch die P-Aufnahme durch Lolium perenne und Trifolium repens untersucht. Als Substrat dienten drei Böden, die entweder seit mindestens 1989 keine P-Gabe mehr erhalten hatten (0F) oder die jährlich P-Gaben im Umfang der P-Entzüge durch die vorgängigen Kulturen erhalten hatten und deshalb P-Rückstände enthielten (F). Es ergaben sich folgende Verfahren: 0F: ohne P aus Düngerrückständen und frischer Düngung; 0F+DAP: mit P aus frischer Düngung (Diammoniumphosphat, 15 mg P (kg Boden),1); F: mit P aus Düngerrückständen; F+DAP: mit P aus Düngerrückständen und frischer Düngung. In den Verfahren 0F + DAP und F + DAP war DAP mit 33PO4 markiert. In den Verfahren 0F und F war der verfügbare P des Bodens mit carrier-freiem 33PO4 markiert. Dies ermöglichte die Erfassung der Aufnahme von P durch die Pflanzen differenziert nach Herkunft aus Boden, Düngerrückständen und frischem Dünger. Von Düngerrückständen stammten 14,62,%, von frischem Dünger 7,28,% des in den Sprossen der Pflanzen gefundenen P. Der von Düngerrückständen stammende Anteil P in den Pflanzensprossen war korreliert mit dem gesamten Gehalt an P das dem Boden als Dünger zugeführt worden war. Der von frischem DAP stammende Anteil war korreliert mit der P-Konzentration in der Bodenlösung. [source] Blue-emitting AlN:Eu2+ Powder Phosphor Prepared by Spark Plasma SinteringJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2010Hyoung-SeoK Do Blue-emitting AlN:Eu2+ powder phosphor was synthesized by spark plasma sintering (SPS) using AlN, Si3N4, and Eu2O3 as the starting materials, and its luminescence properties were investigated. A single-phase Eu- and Si-co-doped AlN powder was successfully fabricated by SPS in the range of 1650°,1800°C for 5 min. The AlN:Eu2+ obtained exhibited a strong blue emission at 480 nm under the excitation of ,exc=340 nm and an electron beam. The highest photoluminescence intensity was observed in the phosphor sintered at 1700°C, which was comparable to that of the phosphor prepared by gas pressure sintering at 1750°C for 4 h. [source] Neue Modifikationen des PhosphorsCHEMIE IN UNSERER ZEIT (CHIUZ), Issue 1 2005Michael Bräu Kürzlich konnten zwei neue Modifikationen des schon lange bekannten Elementes identifiziert werden: Es handelt sich um Phosphor in Form von Polymeren mit Durchmessern von weniger als 50 pm. [source] ChemInform Abstract: Synthesis and Luminescent Properties of Tb3+ -Activated Yttrium Indium Germanate Phosphor.CHEMINFORM, Issue 21 2008Yee-Shin Chang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Photoluminescence Properties of a Novel Phosphor, Na3La9O3 (BO3)8:RE3+ (RE: Eu, Tb).CHEMINFORM, Issue 4 2008Xiaoyan Bai Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Efficient X-Ray Generation of Sm2+ in Nanocrystalline BaFCl/Sm3+: A Photoluminescent X-Ray Storage Phosphor.CHEMINFORM, Issue 45 2007Hans Riesen Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis of YAG:Ce Phosphor via Different Aluminum Sources and Precipitation Processes.CHEMINFORM, Issue 33 2006C. C. Chiang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Preparation of Nanocrystalline Lu2O3:Eu Phosphor via a Molten Salts Route.CHEMINFORM, Issue 3 2005J. Trojan-Piegza Abstract For Abstract see ChemInform Abstract in Full Text. [source] Simultaneous Optimization of Luminance and Color Chromaticity of Phosphors Using a Nondominated Sorting Genetic AlgorithmADVANCED FUNCTIONAL MATERIALS, Issue 11 2010Asish Kumar Sharma Abstract Acquiring materials that simultaneously meet two or more conflicting requirements is very difficult. For instance, a situation wherein the color chromaticity and photoluminescence (PL) intensity of phosphors conflict with one another is a frequent problem. Therefore, identification of a good phosphor that simultaneously exhibits both desirable PL intensity and color chromaticity is a challenge. A high-throughput synthesis and characterization strategy that was reinforced by a nondominated sorting genetic algorithm (NSGA)-based optimization process was employed to simultaneously optimize both the PL intensity and color chromaticity of a MgO,ZnO,SrO,CaO,BaO,Al2O3,Ga2O3,MnO system. NSGA operations, such as Pareto sorting and niche sharing, and the ensuing high-throughput synthesis and characterization resulted in identification of promising green phosphors, i.e., Mn2+ -doped AB2O4 (A,=,alkali earth, B,=,Al and Ga) spinel solid solutions, for use in either plasma display panels or cold cathode fluorescent lamps. [source] 980-nm Laser-Driven Photovoltaic Cells Based on Rare-Earth Up-Converting Phosphors for Biomedical ApplicationsADVANCED FUNCTIONAL MATERIALS, Issue 23 2009Zhigang Chen Abstract A prerequisite for designing and constructing wireless biological nanorobots is to obtain an electrical source that is continuously available in the operational biological environment. Herein the first preparation of 980-nm laser-driven photovoltaic cells (980LD-PVCs) by introducing of a film of rare-earth up-converting nanophosphors in conventional dye-sensitized solar cells is reported. Under the irradiation of a 980-nm laser with a power of 1,W, the visible up-converting luminescence of rare-earth nanophosphors can be efficiently absorbed by the dyes in 980LD-PVCs so that they exhibit a maximal output power of 0.47 mW. In particular, after being covered with 1 to 6 layers of pig intestines (thickness: ca. 1,mm per layer) as a model of biological tissues, 980LD-PVCs still possess a maximal output power of between 0.28 and 0.02,mW, which is efficient enough to drive many kinds of biodevices. This research opens up the possibility of preparing and/or developing novel electrical sources for wireless biological nanorobots and many other biodevices. [source] Discovery of New Green Phosphors and Minimization of Experimental Inconsistency Using a Multi-Objective Genetic Algorithm-Assisted Combinatorial MethodADVANCED FUNCTIONAL MATERIALS, Issue 11 2009Asish Kumar Sharma Abstract A multi-objective genetic algorithm-assisted combinatorial materials search (MOGACMS) strategy was employed to develop a new green phosphor for use in a cold cathode fluorescent lamp (CCFL) for a back light unit (BLU) in liquid crystal display (LCD) applications. MOGACMS is a method for the systematic control of experimental inconsistency, which is one of the most troublesome and difficult problems in high-throughput combinatorial experiments. Experimental inconsistency is a very serious problem faced by all scientists in the field of combinatorial materials science. For this study, experimental inconsistency and material property were selected as dual objective functions that were simultaneously optimized. Specifically, in an attempt to search for promising phosphors with high reproducibility, luminance was maximized and experimental inconsistency was minimized using the MOGACMS strategy. A divalent manganese-doped alkali alkaline germanium oxide system was screened using MOGACMS. As a result of MOGA reiteration, we identified a phosphor, Na2MgGeO4:Mn2+, with improved luminance and reliable reproducibility. [source] A One-Step Method for the Growth of Ga2O3 -Nanorod-Based White-Light-Emitting PhosphorsADVANCED MATERIALS, Issue 35 2009Sampathkumar Chrisolite Vanithakumari A one-step synthesis of Ga2O3 nanorods by heating molten gallium in ambient air at high temperatures is presented. The high-temperature synthesis creates oxygen vacancies and incorporates nitrogen from the environment. The oxygen vacancy in Ga2O3 is responsible for the emission in the blue,green region, while nitrogen in Ga2O3 is responsible for red emission. [source] En Route to High External Quantum Efficiency (,12%), Organic True-Blue-Light-Emitting Diodes Employing Novel Design of Iridium (III) PhosphorsADVANCED MATERIALS, Issue 21 2009Yuan-Chieh Chiu True-blue Ir(III) phosphors are designed, synthesized, and applied to multilayered organic true-blue-light-emitting diodes with CIEx,y color chromaticity of (0.15,0.11) and maximum external quantum efficiency of ,12%, demonstrating unprecedented performance among all blue-phosphorescent OLEDs ever documented. The molecular-design strategy and subsequent device-fabrication protocol reveal a major development in OLEDs. [source] Facile Synthesis of New Full-Color-Emitting BCNO Phosphors with High Quantum Efficiency,ADVANCED MATERIALS, Issue 17 2008Takashi Ogi A novel full-color-emitting phosphor composed of B, C, N, and O atoms is prepared by a one-step solution process from inexpensive precursors at ambient atmosphere and relatively low temperatures (below 900,°C). Emission from this novel phosphor can be tuned from the violet to the near-red, as illustrated in the figure, simply by varying the carbon content in the samples. [source] Synthesis and Luminescence Properties of Orange,Red-Emitting M2Si5N8:Eu2+ (M=Ca, Sr, Ba) Light-Emitting Diode Conversion Phosphors by a Simple Nitridation of MSi2INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 4 2009Hui-Li Li Eu2+ -doped M2Si5N8 (M=Ca, Sr, Ba) orange,red phosphors were successfully prepared by a simple, direct, and efficient solid-state reaction using air-stable MSi2, Eu2O3, and ,-Si3N4 as the starting materials under N2,H2 (5%) atmosphere. The influence of the type of the alkaline-earth ion on the phase structure and luminescence properties has been investigated. The results show that the synthesized powders have a single-phase crystal structure of M2Si5N8 for M=Ca, Sr, and a little amount of BaSi7N10 impurity phase for M=Ba. Under the blue light excitation, M2Si5N8:Eu2+ shows a typical broad band emission of Eu2+ ranging from orange to red (585,620 nm) depending on the type of M ion. The emission intensity, conversion efficiency, and thermal stability increase with the sequence of Ca The course of some bone remodelling plasma metabolites in healthy horses and in horses offered a calcium-deficient dietJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3-4 2003V. De Behr Summary An inquiry was carried out to assess the concentrations of plasma metabolites related to bone remodelling in 21 saddle horses of Warmblood breed aged 4,26 years, five draught horses of Ardennes breed aged 4,10 years, and 10 Ardennes foals aged 9,11 months. They were fed according to normal feeding practice in Belgium. The changes in some bone remodelling plasma metabolite concentrations were studied when an unbalanced diet was offered and later corrected for four Warmblood horses. Bone formation was evaluated by bone alkaline phosphatase (BALP), total alkaline phosphatase (TALP) and osteocalcin (bone gla-protein, OC). Bone resorption was assessed by hydroxyproline (HYP). Total calcium, ionized calcium, phosphorus (P) and 25-hydroxyvitamin D3 [25-(OH)D] concentrations were more or less constant. The comparison of four bone remodelling factors between the Ardennes and Warmblood horses showed higher concentrations in the Ardennes breed. Bone marker concentrations decreased according to age. The correction of the unbalanced Ca : P diet induced inconsistent effects at plasma level. The interpretation of the different bone parameters appeared to be difficult if not associated with other parameters such as a complete anamnesis and clinical examination of the animal in addition to dietary evaluation. Zusammenfassung Verlauf verschiedener Knochenmarker bei gesunden Pferden und bei Pferden, welche mit einer in Bezug auf Kalzium unausgewogenen Ration gefüttert wurden Eine Studie zur Erfassung der Konzentrationen von Knochenmarkern wurde bei 21 Warmblütern im Alter von 4 bis 26 Jahren, fünf Ardenner Kaltblütern im Alter von 4 bis 10 Jahren und 10 Ardenner Kaltblutfohlen im Alter von 9 bis 11 Monaten durchgeführt. Die Pferde wurden gemäss der normalen Fütterungpraxis in Belgien gefüttert. Der Verlauf der Knochenmarkerkonzentrationen wurde auch bei vier Pferden gemessen, die zunächst mit einer unausgewogenen Ration in Bezug auf Kalzium und dann mit einer korrigierenden Ration gefüttert wurden. Der Knochenaufbau wurde anhand der Aktivität der knochenspezifischen alkalischen Phosphatase (BALP), der totalen alkalischen Phosphatasen (TALP) und anhand des Osteocalcin (bone gla-proteine, OC) gemessen. Der Knochenabbau wurde anhand des Hydroxyprolins (HYP) gemessen. Die Konzentrationen des totalen Kalziums, ionisierten Kalziums, Phosphors (P), und 25-Hydroxyvitamin D3 [25(OH)D] waren unverändert. Beim Vergleich der vier gemessenen Knochenmakerkonzentrationen bei den Ardenner Kaltblütern mit den Warmblutpferden konnte gezeigt werden, dass die Kaltblüter deutlich höhere Konzentrationen hatten als die Warmblüter. Die Konzentrationen der Marker nahmen mit steigendem Alter der Pferde ab. Die Korrektur der unausgewogenen Ca:P Ration ergab nicht eindeutige Veränderungen der Plasmakonzentrationen der verschiedenen Marker. Die Interpretation der verschiedenen Knochenmarker erscheint schwierig, wenn nicht andere Parameter, wie eine komplette Anamnese und eine klinische Untersuchung, sowie eine Auswertung der Ration hinzugezogen werden. [source] Potential role of phosphate buffering capacity of soils in fertilizer management strategies fitted to environmental goals,JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2003Phillip Ehlert Abstract Sorption behavior and buffering of phosphorus (P) are important, both from an agricultural and an environmental point of view. The objectives of this study were to investigate: (1) the kinetics of the transfer of P from soil to soil solution and assessing P buffering capacity of soils (PBC), as a function of soil solution P; (2) the effect of PBC on soil P status fitted to environmental targets for water quality; (3) the effect of PBC on crop response. PBC was derived from the non-linear Q-I curve describing the time-dependent relationship between plant-available reserve of soil P (Q) versus soil solution P (I). The Q-I curve was determined in soil suspension using sorption and isotopic dilution methods for soil samples from French, Swedish, and Dutch field trials. Soils with low PBC values were more sensitive to the loss of P to the environment, required higher critical value in soil solution P to comply with P demand of maize, and had higher change in soil solution P per unit of P budget. In different soils, both the critical soil solution P for maize and the change in soil solution P per unit of P balance varied inversely with PBC. It is concluded that (1) PBC plays a key role in determining the agronomic and environmental threshold levels of available P content in the soils, and (2) PBC is a prerequisite for the development of more environmentally oriented fertilization recommendation systems. Potenzielle Bedeutung der Phosphat-Pufferkapazität des Bodens für umweltgerechte Düngungsstategien Bindungsverhalten und Pufferkapazität des Phosphors (P) im Boden ist wichtig, sowohl aus Sicht der Landwirtschaft als auch des Umweltschutzes. In dieser Untersuchung sollten folgende Probleme untersucht werden: (1) Kinetik des P-Transfers von der Festphase in die Bodenlösung und Abschätzung der P-Pufferkapazität (PBC) als Funktion der P-Konzentration in der Bodenlösung; (2) die Wirkung der PBC auf den Boden-P-Status im Hinblick auf Qualitätsziele für Wasser; (3) Wirkung der PBC auf die P-Aufnahme der Pflanze. Die PBC wurde abgeleitet aus der nichtlinearen Q-I-Kurve, die die zeitabhängige Beziehung zwischen dem Gehalt an pflanzenverfügbarem Boden-P (Q) und der P-Konzentration in der Bodenlösung (I) beschreibt. Die Q-I-Kurve wurde in Bodensupensionen mit Sorptions- und Isotopen-Verdünnungsmethoden an Bodenproben aus Feldversuchen in Frankreich, Schweden und den Niederlanden bestimmt. Böden mit niedriger PBC waren sensitiver für P-Austräge in die Umwelt, erforderten höhere Grenzkonzentrationen in der Bodenlösung zur Bedarfsdeckung bei Mais und zeigten größere Konzentrationsveränderungen in der Bodenlösung je Einheit der P-Bilanz. Die Grenzkonzentrationen in der Bodenlösung zur Bedarfsdeckung bei Mais und Konzentrationsveränderungen in der Bodenlösung je Einheit der P-Bilanz variierten in unterschiedlichen Böden invers mit Variation der PBC. Aus den Untersuchungen folgte, dass (1) die PBC ein Schlüssel-Parameter zur Bestimmung agronomischer und umweltrelevanter Grenzwerte der Gehalte an verfügbarem P im Boden ist und (2) somit eine Voraussetzung für die Entwicklung mehr umweltorientierter Systeme der Düngungsempfehlungen. [source] Preparation and Photoluminescence Properties of Novel Color-Tunable MgY4Si3O13:Ce3+, Tb3+ Phosphors for Ultraviolet Light-Emitting DiodesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2010Hau-Yun Chung Oxide-based phosphors MgY4Si3O13 codoped with Ce3+ and Tb3+ were prepared in this study. Broad Ce3+ excitation spectra with the highest intensity at 330 nm were found for MgY4Si3O13:Ce3+, Tb3+ phosphors. Emission lines ranging from 450 to 650 nm originated from the 5D4,7FJ (J=6, 5, 4, 3) transitions of Tb3+ ions. The energy transfer from Ce3+ to Tb3+ occurred effectively in MgY4Si3O13:Ce3+, Tb3+ with a dipole,quadrupole interaction. Codoping Ce3+ with Tb3+ significantly increased the emission intensity of the prepared phosphors. Increasing the Tb3+ concentration led to the chromaticity coordinates of the prepared samples greatly shifting from the blue to the green region, extending the applicability of MgY4Si3O13:Ce3+, Tb3+ phosphors in solid-state lighting. [source] Synthesis and Luminescence Properties of BaMoO4:Sm3+ PhosphorsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2010Zhiguo Xia BaMoO4:Sm3+ phosphor system with a tetragonal structure was synthesized via a high-temperature solid-state method. The charge compensated behaviors, 2Ba2+,Sm3++M+, where M+ is a monovalent cation like Li+, Na+, and K+ acting as a charge compensator, were investigated in this paper. It has been found that BaMoO4:Sm3+ phosphor by doping with K+ ions show greatly enhanced reddish orange emission compared with pure BaMoO4:Sm3+ sample. Investigation on Sm3+ and K+ concentration-dependent emission spectra indicated that Ba0.84MoO4:0.08Sm3+,0.12K+ phosphor exhibited the strongest reddish orange emission with a CIE values of x=0.55 and y=0.43. After irradiation under the 402 nm ultraviolet (UV) excitation, three emission peaks centered at 561, 598, and 642 nm corresponding to the 4G5/2 to 6HJ (J=5/2, 7/2, 9/2) emission lines of Sm3+ were obviously observed, and the lifetimes of three emissions (4G5/2,6HJ=5/2, 7/2, 9/2) have been calculated based on the measured decay curves. [source] Upconversion Luminescence in ,-AlON:Yb3+,Tm3+ Ceramic PhosphorsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2009Fang Zhang Upconversion emission properties of ,-AlON:Yb3+,Tm3+ phosphors were investigated under single-wavelength diode laser excitation of 980 nm. Blue (479 nm) and red (653 nm) emission bands were observed which correspond to the transitions of 1G4,3H6 and 1G4,3F4 of Tm3+ ions, respectively. The upconversion spectra show a concentration-dependent luminescence intensity, reaching its peak at a concentration of 1.2 mol% Yb and 0.5 mol% Tm. Pump power dependence of the upconversion emission intensity (P,I) revealed that a two-photon process was involved in the blue and red emissions. [source] Neue Modifikationen des PhosphorsCHEMIE IN UNSERER ZEIT (CHIUZ), Issue 1 2005Michael Bräu Kürzlich konnten zwei neue Modifikationen des schon lange bekannten Elementes identifiziert werden: Es handelt sich um Phosphor in Form von Polymeren mit Durchmessern von weniger als 50 pm. [source] ChemInform Abstract: Enhanced Photoluminescence of Ba2GdNbO6: Eu3+/Dy3+ Phosphors by Li+ Doping.CHEMINFORM, Issue 21 2008C. C. Yu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Novel Class of Aeschynite Structure LaNbTiO6 -Based Orange-Red Phosphors via a Modified Combustion Approach.CHEMINFORM, Issue 5 2008Qian Ma Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Synthesis and Photoluminescent Properties of Ce3+ Doped Terbium Aluminum Garnet Phosphors.CHEMINFORM, Issue 24 2007C. C. Chiang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Highly Enhanced Luminescence of GdTaO4:Eu3+ Phosphors by Codoping with Zn2+ Ions.CHEMINFORM, Issue 9 2007Mu Gu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Preparation and Characterization of Nanosized ZnGa2O4 Phosphors.CHEMINFORM, Issue 39 2004She-huang Wu Abstract For Abstract see ChemInform Abstract in Full Text. [source]
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