In this paper, CuO nanoparticles were synthetized via a sol–gel method and their corresponding gas sensor was achieved simultaneously.

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Luminescence D 6540Eu 2+ Activated Long Persistent Strontium Aluminate Nano Scaled Phosphor Prepared by Precipitation Method. -SrAl2O4:Eu 2+ Dy 3+ (I) and Sr4Al14O25:Eu 2+ Dy 3+ (II) phosphors are synthesized by calcination of a precipitated precursor at 1200 and 1300°C, respectively. The precursor is prepared from aqueous solutions of Al(NO3)3, Sr(NO3)2, and Ln(NO3)3 (Ln: Eu, Dy) using (NH4)2CO3 as precipitation agent. The samples are characterized by SEM, DSC-TG, XRD, and luminescence spectroscopy. Both the low-temperature product (I) and the high-temperature product (II) show luminescence upon UV illumination with an emission peak at 480 and 505 nm, respectively. Both phosphors exhibit long persistent afterglow, which is superior for compound (II).-(CHANG*, C.; YUAN, Z.; MAO, D.; J.

Nitrogen-doped SrTiO 3 samples have been successfully prepared by nitrogen-ion implantation. X-ray photoelectron spectra clearly indicate the presence of nitrogen dopants in the crystal lattice of SrTiO 3 . The ultravioletvisible absorption spectra of nitrogen-doped SrTiO 3 show enhanced visible light absorption in the range of 400-500 nm, which contributs to the localized N 2p state in the band gap of SrTiO 3 . The resistance coefficient of temperature is positive indicating metallic conducting behavior. The nonlinear dependence of voltage on current at liquid-nitrogen temperatures indicates a possible energy barrier in the grain boundary. PACS Nos.: 72.20.−i, 72.80.Ga, 78.20.−e Résumé : Nous avons réussi à préparer des échantillons de SrTiO 3 dopés à l'azote par implantation d'ions d'azote.Les spectres X photoélectroniques indiquent clairement la présence de l'azote dans le cristal de SrTiO 3 . Le spectre d'absorption visible-UV du SrTiO 3 dopé à l'azote montre une augmentation dans le domaine 400-500 nm du visible, due à l'état localisé 2p du N dans la bande interdite du SrTiO 3 . Le coefficient de résistance en température est positif, indiquant un comportement métallique conducteur. La dépendance non linéaire du voltage sur le courant aux températures de l'azote liquide indique une possible barrière d'énergie aux frontières des grains.[Traduit par la Rédaction]

Luminescence Luminescence D 6540Rietveld Analysis for Eu 2+ Doped 4SrO·7Al 2 O 3 and Its Luminescent Properties.-As revealed by powder XRD (Sr 0.975 Eu 0.025 O) 4 ·7Al 2 O 3 crystallizes in the orthorhombic space group Pmma. There are two Sr 2+ sites that can be substituted by Eu 2+ ions to form two emission centers at 400 and 490 nm, respectively. The 4SrO·7Al2O3 phosphors doped with Eu 2+ and Dy 3+ show excellent properties of long afterglow. The initial intensity and long afterglow duration vary with the concentration of Eu 2+ . The best afterglow behavior is shown by 4SrO·7Al 2 O 3 phosphors doped with 0.012 Eu 2+ and 0.

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Background China is a highly endemic area of chronic hepatitis B. The accuracy of common noninvasive biomarkers including TE, APRI and FIB-4 for staging fibrosis is not enough in Chinese cohort.Methods Using liver biopsy as a gold standard, a novel noninvasive indicator was developed using laboratory tests, ultrasound measurements and liver stiffness measurements with machine learning techniques to predict significant fibrosis and cirrhosis in patients infected with HBV in north and east part of China. We retrospectively evaluated the diagnostic performance of the novel indicator named FibroBox, Fibroscan, aspartate transaminase-to-platelet ratio index (APRI), and FIB-4 in HBV patients from Jilin and Huai’an (training sets) and also in Anhui and Beijing cohorts (validation sets).Results Of 1289 eligible HBV patients who had liver histological data, 63.2% had significant fibrosis and 22.5% had cirrhosis. In lasso regression and filter methods, fibroscan results, platelet count, alanine transaminase (ALT), prothrombin time (PT), type III procollagen aminoterminal peptide (PIIINP), type IV collagen, laminin, hyaluronic acid (HA) and diameter of spleen vein were finally selected as input variables in FibroBox. Consequently, FibroBox was developed of which the area under the receiver operating characteristic curve (AUROC) was significantly higher than that of TE, APRI and FIB-4 to predicting significant fibrosis and cirrhosis. In the Anhui and Beijing cohort, the AUROC of FibroBox was higher than TE, APRI and FIB-4 for significant fibrosis (0.88, 95% CI 0.72 to 0.82; 0.87, 95% CI 0.83 to 0.91, respectively) and cirrhosis (0.87, 95% CI 0.82 to 0.92; 0.90, 95% CI 0.85 to 0.94, respectively).Conclusions FibroBox, compared with TE, APRI and FIB-4, has a better performance in predicting liver fibrosis in Chinese cohorts, which may serve as a feasible alternative to liver biopsy.