211   Highly efficient and selective enrichment of puerarin from Radix Puerariae by molecularly imprinted solid-phase extraction Highly efficient and selective enrichment of puerarin from Radix Puerariae by molecularly imprinted solid-phase extraction    2010 A novel highly efficient and selective puerarin (PR) enrichment procedure based on the use of molecularly imprinted polymer (MIP) as solid-phase extraction (SPE) materials has been developed and evaluated. In the present study, two widely used functional monomers acrylamide (AA) and methacrylic acid (MAA) were compared theoretically and experimentally as the candidates for MIP preparation, showing that AA was a better functional monomer to prepare MIP. Spectroscopic analysis in conjunction with ... 查看全文

212   Magnetic properties of high-coercivity nanocrystalline Pr-Fe-Co-Al-B bulk amorphous Magnetic properties of high-coercivity nanocrystalline Pr-Fe-Co-Al-B bulk amorphous    2010 Pr-Fe-Co-Al-B bulk amorphous prepared by high energy milling Shows a coereivity of 8 kOe. The controlled nanocrystallization enhances the coercivity to 30 kOe and remanent magnetization to 90 emu/g. Those values are the highest ever found for annealed bulk amorphons isotropic systems. The grain size for optimal magnetic properties of about 28 nm is estimated from HRTEM analysis. The coexistence of two crystalline magnetic phases. ferromagnetic Pr 2(Fe, Co, Al)14B and antiferromagnetic Pr6(Fe, Co... 查看全文

213   High performance praseodymium nickelate oxide cathode for low temperature solid oxide fuel cell High performance praseodymium nickelate oxide cathode for low temperature solid oxide fuel cell    2011 The praseodymium nickelate oxide Pr2NiO4+δ, a mixed conducting oxide with the K2NiF4-type structure, was evaluated as cathode for low temperature solid oxide fuel cells (T = 873 K). The electrochemical performance of the cathode has been improved by optimization of the microstructure of the porous cathode combined with the use of a ceria barrier layer in between the cathode and zirconia electrolyte. Both low polarization and ohmic resistances were obtained using Pr2NiO 4+δ-powders wi... 查看全文

214   LaTiO2N as a Visible-Light (≤600 nm)-Driven Photocatalyst (2) LaTiO2N as a Visible-Light (≤600 nm)-Driven Photocatalyst (2) Asako Kasahara,† Kohta Nukumizu,† Tsuyoshi Takata,† Junko N. Kondo,† Michikazu Hara,† Hisayoshi Koba    2002 LaTiO2N, a Ti-based oxynitride, was studied as a visible-light (420?600 nm)-driven photocatalyst. DFT calculation for LaTiO2N indicated that the top of the valence band consists predominantly of N 2p orbitals with a small contribution by O 2p orbitals, while the bottom of the conduction band is made up entirely of empty Ti 3d orbitals. LaTiO2N was synthesized from a La2Ti2O7 precursor at 1123 K under NH3 flow. The relationship between the preparation condition and the photocatalytic activities o... 查看全文

215   Studies on microstructure and magnetic properties of (Nd1-xPrx)10.5 (FeCoZr)83.5B6 alloy Studies on microstructure and magnetic properties of (Nd1-xPrx)10.5 (FeCoZr)83.5B6 alloy    2004 By sub-overquenching to get an amorphous alloy with fine crystallites and annealing under the optimal conditions, the melt-spun (Nd1-xPrx)10.5 (FeCoZr)83.5B6 (x=0, 0.2, 0.4, 0.6, 0.8, 1.0) bonded magnets with the best magnetic properties were prepared. The effect of Pr on thermal stability, microstructure and magnetic properties of the alloy was investigated. The substitution of Nd by Pr leads the crystallization temperature and crystallization energy to decrease. The thermal stability differenc... 查看全文

216   Strong red emission in Pr doped (Bi0.5Na0.5)TiO 3 ferroelectric ceramics Strong red emission in Pr doped (Bi0.5Na0.5)TiO 3 ferroelectric ceramics    2011 The photoluminescence of Pr doped (Bi0.5Na0.5) TiO3 ferroelectric ceramics prepared by conventional solid-state reaction were investigated. A bright red emission is observed at room temperature, which ascribed to 1D2&rarr3H 4 transition. The excitation bands are mainly located at 440 ∼ 505 nm, which is adaptable to the emission band of commercial blue light-emitting diodes (LEDs) chips. The optimal emission intensity was also obtained when Pr doping level was 0.003 mol. Meanwhile, the enhanc... 查看全文

217   Linear periodic boundary-value problem for a second-order hyperbolic equation. I Linear periodic boundary-value problem for a second-order hyperbolic equation. I N. G. Khoma    1998 In three spaces, we obtain exact classical solutions of the boundary-value periodic problem u tt−a 2 u xx=g(x,t), u(0,t)=u(π,t)=0, u(x,t+T)=u(x,t)=0, x,t∈ĝ 查看全文

218   Intraoperative application versus postoperative mitomycin C eye drops in pterygium surgery Intraoperative application versus postoperative mitomycin C eye drops in pterygium surgery RAMASAMY GOVINDARAJAN, OLUWASEUN BABALOLA, MAGDY GAD-EL-KAREEM, NAGENDRA S KODALI, JUDITH ARONSON an    2003 查看全文

219   Pancharatnam geometric phase originating from successive partial projections Pancharatnam geometric phase originating from successive partial projections Sohrab Abbas;Apoorva G. Wagh    2008 The spin of a polarized neutron beam subjected to a partial projection in another direction, traces a geodesic arc in the 2-sphere ray space. We delineate the geometric phase resulting from two successive partial projections on a general quantal state and derive the direction and strength of the third partial projection that would close the geodesic triangle. The constraint for the three successive partial projections to be identically equivalent to a net spin rotation re... 查看全文

220   Optimizing the storage and retrieval efficiency of a solid-state quantum memory through tailored state preparation Optimizing the storage and retrieval efficiency of a solid-state quantum memory through tailored state preparation    2007 We theoretically investigate the feasibility of using spectral hole burning in Pr3+:Y2SiO5 to prepare an ensemble of Pr3+ ions with a spectral distribution optimized for use as a quantum memory for single-photon states. We introduce figures of merit for the spectral distribution of the Pr3+ ions when used as a quantum-memory node in a Duan-Lukin-Cirac-Zoller-type quantum-repeater scheme. Finally, we describe progress toward optimizing the hole-burning sequence by using a computational model of t... 查看全文

221   Preparation and characterization of (1-Me-indenyl)Ni(PR3)(CC-Ph) (R = Cy, Ph) and alkyne polymerization catalysis Preparation and characterization of (1-Me-indenyl)Ni(PR3)(CC-Ph) (R = Cy, Ph) and alkyne polymerization catalysis    1999 The complexes (1-Me-Ind)(PR3)Ni-CC-Ph (R = Ph and Cy) have been prepared and characterized spectroscopically and by means of single-crystal structural analyses. These compounds are inert toward the insertion of alkynes, but when combined with methylaluminoxane (MAO), they form. active catalysts for the homogeneous polymerization of phenylacetylene. cis-Poly(Ph-CC-H) is thus obtained with Mw values in the range of 104 and relatively narrow polydispersities. The combination of the corresponding Ni... 查看全文

222   Nanocrystalline exchange-coupled Pr-Fe-B permanent magnets Nanocrystalline exchange-coupled Pr-Fe-B permanent magnets    1997 Nanocomposite Pr2Fe14B/α-Fe permanent magnets were prepared by melt spinning and subsequent crystallization of Pr8Fe86B6 amorphous precursors. The microstructure is a two-phase nanocomposite of Pr2Fe14B and soft magnetic α-Fe with an average size of 30 nm. X-ray diffraction, Thermomagnetic analysis and TEM analysis indicate that amorphous Pr8Fe86B6 alloy crystallizes through the process of Am->Am prime +α-Fe->Pr2Fe23B3+α - Fe->Pr2Fe14B+α-Fe. The highest value ... 查看全文

223   Effects of Parenting Style. on Personal and Social Variables for Asian Adolescents Effects of Parenting Style. on Personal and Social Variables for Asian Adolescents Giovanni Mantovani, Giorgio Astara, Biancarosa Lampis, Alessandro Bianchi, Luigi Curreli, Walter Orr    2010 Impact of perceived parenting style. on adolescents' self-reliance, interpersonal relations, sense of inadequacy, and attitude to school, after controlling for effects of adolescents' self-esteem, was examined in a sample of 548 Asian adolescents. Fathers' perceived parenting style. was significantly associated with adolescents' sense of inadequacy for the entire sample as well as for Chinese adolescents. Fathers' perceived parenting style. was also significantly associated with Malay adolescent... 查看全文

224   Preparation and luminescence properties of gadolinium aluminate perovskite phosphor discrete combinatorial library Preparation and luminescence properties of gadolinium aluminate perovskite phosphor discrete combinatorial library    2012 Combinatorial material synthesis and high throughput evaluation technique have been developed to accelerate material discovering and optimizing. The thin-film combinatorial material library (or material chip), similar to the integrated circuit chip, contains thousands even millions of different compounds, and could be used to screen for the desirable physical or chemical properties. In our work, the rare earth activated gadolinium aluminate perovskite phosphor(GAP:RE1x, RE2y, RE ion vary among E... 查看全文

225   Anaesthetists, lawyers and the public Anaesthetists, lawyers and the public Giovanni Mantovani, Giorgio Astara, Biancarosa Lampis, Alessandro Bianchi, Luigi Curreli, Walter Orr    2007 查看全文

226   Effects of rare-earth elements on the glass-forming ability and mechanical properties of Cu46Zr47-x Al7M x (M = Ce, Pr, Tb, and Gd) bulk metallic glasses Effects of rare-earth elements on the glass-forming ability and mechanical properties of Cu46Zr47-x Al7M x (M = Ce, Pr, Tb, and Gd) bulk metallic glasses    2010 Cu46Zr47-x Al7M x (M = Ce, Pr, Tb, and Gd) bulk metallic glassy (BMG) alloys were prepared by copper-mold vacuum suction casting. The effects of rare-earth elements on the glass-forming ability (GFA), thermal stability, and mechanical properties of Cu 46Zr47-x Al7M x were investigated. The GFA of Cu46Zr47-x Al7M x (M = Ce, Pr) alloys is dependent on the content of Ce and Pr, and the optimal content is 4 at.%. Cu46Zr47-x Al7Tb x (x = 2, 4, and 5) amorphous alloys with a diameter of 5 mm can be pr... 查看全文

227   Ellagic Acid and Ellagitannins Affect on Sedimentation in Muscadine Juice and Wine Ellagic Acid and Ellagitannins Affect on Sedimentation in Muscadine Juice and Wine Joon-Hee Lee and Stephen T. Talcott*    2002 A mechanism for the formation of water-insoluble sediments in wines and juices made from red and white muscadine grapes (Vitis rotundifolia) was investigated as a function of processing methodology and storage. Sediments are considered quality defects in muscadine grape products, and their presence may influence consumer acceptability and expansion of retail markets. Processing regimes included both hot (70 °C) and cold (25 °C) press techniques for wine or juice production, and fermentations i... 查看全文

228   Preparation of superconducting magnetostatic wave (MSW) devices consisting of High-Tc superconductor (HTS)/Perovskite-type manganite heterostructures: Application of Pr0.85Ca0.15MnO3 as a MSW Waveguid Preparation of superconducting magnetostatic wave (MSW) devices consisting of High-Tc superconductor (HTS)/Perovskite-type manganite heterostructures: Application of Pr0.85Ca0.15MnO3 as a MSW Waveguid    2001 Electric and magnetic properties of Pr0.85Ca0.15MnO3 (PCMO) have been investigated in order to apply the material to superconducting microwave devices. PCMO films are prepared on (100) surfaces of a (La0.3Sr0.7) (Al0.65Ta0.35)O3 (LSAT) single crystal by a pulsed laser deposition technique. By optimizing the deposition conditions, c-axis oriented PCMO epitaxial films are obtained. The Curie temperature (TC) of these PCMO films is approximately 130 K. The remanent magnetization and the coercive fi... 查看全文

229   Green and red emission for (K0.5Na0.5)NbO 3:Pr ceramics Green and red emission for (K0.5Na0.5)NbO 3:Pr ceramics    2012 The photoluminescence properties of Pr-doped K0.5Na 0.5NbO3 (KNN) ceramics were prepared by the solid-state reaction method and investigated as a function of Pr concentration and sintering temperature. The excitation band ranging from 430 to 500 nm covers the emission wavelength of all commercial blue light-emitting diode chips. The photoluminescence spectra of KNN:Pr exhibit strong green (528 nm) and red (617 nm and 650 nm) emissions. The optimum doping concentration of Pr in KNN is 0.5 mol.%, ... 查看全文

230   Reply to Comment on “Submicrometer Plate Heights for Capillaries Packed with Silica Colloidal Crystals” Reply to Comment on “Submicrometer Plate Heights for Capillaries Packed with Silica Colloidal Crystals” Douglas S. Malkin†, Bingchuan Wei‡, and Mary J. Wirth*‡    2010 查看全文

231   Influences of (Ce-Zr-La-Pr)O contents on three-way catalyst performances Influences of (Ce-Zr-La-Pr)O contents on three-way catalyst performances    2005 A series of catalysts with (Ce-Zr-La-Pr)O contents range from 0 to 50% in coating and single-palladium loads on substrates were prepared to study effects of (Ce-Zr-La-Pr)O contents on catalytic activities and durability by contrasting the characteristics of light-off, A/F and catalytic conversions of the fresh catalysts with that of the aged catalysts. The results show that (Ce-Zr-La-Pr)O can enhance the catalysts light-off characteristics, widen A/F windows and increase catalytic conversions at... 查看全文

232   Pr doped YBCO films produced by pulsed laser deposition Pr doped YBCO films produced by pulsed laser deposition    2006 Pr doped YBa2Cu3O7-d targets with composition Y1-xPrxBa2Cu3O 7-d where x = 0.0001, 0.001, 0.01, and 0.1 were prepared from oxide powders and used to deposit thin films by pulsed laser deposition using conditions previously optimized for pure YBa2Cu3O 7-d. The Pr dopant was found to be dispersed throughout the film by secondary ion mass spectrometry and the doped films had an increased density of nanoparticles on the surface. The pinning force of the doped samples was found to decrease with incre... 查看全文

233   Photocatalytic degradation of phenol in aqueous solutions by Pr-doped TiO2 nanoparticles Photocatalytic degradation of phenol in aqueous solutions by Pr-doped TiO2 nanoparticles    2007 Photocatalytic degradation of phenol in water was examined using Pr-doped TiO2 nanoparticles. These photocatalysts were synthesized by an acid-peptized sol-gel method from titanium tetra-isopropoxide with different concentrations of Pr(III) dopant and calcination temperatures. Several tools such as XRD, BET surface area, SEM, and EDX, were used to evaluate particle structure, size distribution, and composition. The optical absorption properties of the prepared particles were also measured. Photo... 查看全文

234   Energy transfer between Pr3+ and Mn2+ in K 2YZr(PO4)3: Pr, Mn phosphor Energy transfer between Pr3+ and Mn2+ in K 2YZr(PO4)3: Pr, Mn phosphor    2011 Pr3+, Mn2+ co-doped K2YZr(PO 4)3 samples were prepared by solid-state reaction method and their photoluminescence (PL) properties were investigated in ultra-violet (UV) and vacuum ultra-violet (VUV) region. The results indicated that in Pr 3+ singly doped K2YZr(PO4)3 sample, the first-step transition (1S0 → 1I 6, 3PJ around 405 nm) of Pr3+ is near the ultraviolet (UV) range, not useful for practical application. When Mn2+ was doped as a co-activator ion, the energy of 1S0 → 1I6, 3P J t... 查看全文

235   Preparation and Al3+ enhanced photoluminescence properties of CaTiO3:Pr3+ Preparation and Al3+ enhanced photoluminescence properties of CaTiO3:Pr3+    2006 A enhanced photoluminescence red phosphor of CaTi1-xO 3:Pr3+,Al3+x has been synthesized using nano-TiO2 aerogel, Al(NO3)3, Pr(NO 3)3, CaCO3 as the starting material in ethanol solution by liquid-solid state reaction and high temperature sintering method. The synthesizing conditions have been optimized in this work. The phosphor consists of aggregates of about 500-1000 nm in diameter with observable porosity and has characteristic of the distorted orthorhombic form. of perovskite-type calcium tit... 查看全文

236   Effects of chronic tadalafil use on the testes and sperm parameters of old albino rats Effects of chronic tadalafil use on the testes and sperm parameters of old albino rats P. Erol Duru, Sema Bektas, ouml;mer Genccedil;, Suuml;leyman Pati#x307;r and Adil Denizli    2011 The use of phosphodiesterase-5 inhibitors has become the first-line treatment of erectile dysfunction nowadays. The daily application of tadalafil has become a line of treatment of other diseases such as pulmonary hypertension and cardiomyopathy. This study aimed at exploring whether the chronic use of tadalafil has an adverse effect on the testes and semen of old albino rats. Sixty male albino rats were divided into three groups. Group 1: given 2 ml saline orally for 90 days. Group 2:... 查看全文

237   Preparation, structure and optical properties of Pr:Gd2O 3 phosphor Preparation, structure and optical properties of Pr:Gd2O 3 phosphor    2011 Pr3+-doped Gd2O3 phosphor powders were prepared by co-precipitation method. Their structures during heat-treatments were studied by XRD and IR methods. The pH was optimized to be 8 in the co-precipitation process and the hydroxide precursors were transformed into pure phase cubic Gd2O3 at 500 °C for 1 h. Optical properties of Pr:Gd2O3 phosphor powders were reported. The main emission bands are assigned to 1D2 → 3H4, 3P0 → 3H 6, 3P0 → 3F2 transition of Pr3+ under excitation at ... 查看全文

238   Apparent life-threatening event Apparent life-threatening event ROBERT B. NORDBERG    2010 查看全文

239   Electrides: Early Examples of Quantum Confinement Electrides: Early Examples of Quantum Confinement James L. Dye*    2009 Electrides are ionic solids with cavity-trapped electrons, which serve as the anions. Localization of electrons in well-defined trapping sites and their mutual interactions provide early examples of quantum confinement, a subject of intense current interest. We synthesized the first crystalline electride, Cs+(18-crown-6)2e?, in 1983 and determined its structure in 1986; seven others have been made since. This Account describes progress in the synthesis of both organic and inorganic electrides an... 查看全文

240   Guidance in Religious Conflicts Guidance in Religious Conflicts ROBERT B. NORDBERG    2011 查看全文

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