Phase formations and tunable red luminescence of Na₂CaMg_1−<i>x</i>Mn_<i>x</i>(PO₄)₂ (<i>x</i> = 0.05–1.0)

Lü,, Juan,Du, Fuping,Zhu, Rui,Huang, Yanlin,Seo, Hyo Jin Royal Society of Chemistry 2011 Journal of materials chemistry Vol.21 No.41

<P>Mn<SUP>2+</SUP>-doped phosphates Na<SUB>2</SUB>CaMg<SUB>1−<I>x</I></SUB>Mn<SUB><I>x</I></SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> (<I>x</I> = 0.05–1.0) were prepared by conventional solid-state reaction. X-ray powder diffraction (XRD), the emission and excitation spectra, and decay measurements were employed to characterize the synthesized phosphors. The XRD patterns show that Na<SUB>2</SUB>CaMg<SUB>1−<I>x</I></SUB>Mn<SUB><I>x</I></SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> (<I>x</I> = 0.05–0.3) forms the single low temperature monoclinic phase α-Na<SUB>2</SUB>CaMg(PO<SUB>4</SUB>)<SUB>2</SUB> with the crystal group of <I>P</I>2<SUB>1</SUB>/<I>c</I> (No.14). The heavily Mn<SUP>2+</SUP>-doped Na<SUB>2</SUB>CaMg<SUB>1−<I>x</I></SUB>Mn<SUB><I>x</I></SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> (<I>x</I> = 0.6–1.0) crystallizes in the single high-temperature trigonal phase of β-Na<SUB>2</SUB>CaMg(PO<SUB>4</SUB>)<SUB>2</SUB> with space-group <I>P</I>3̄<I>m</I>1 (No. 164). The members with <I>x</I> = 0.3–0.5 form a series of solid solutions containing two distinct phases, α- and β-Na<SUB>2</SUB>CaMg(PO<SUB>4</SUB>)<SUB>2</SUB>. The dependence of luminescence spectra on the Mn<SUP>2+</SUP>-doping concentration in Na<SUB>2</SUB>CaMg<SUB>1−<I>x</I></SUB>Mn<SUB><I>x</I></SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> (<I>x</I> = 0.05–1.0) was investigated. The great red-shift of Mn<SUP>2+</SUP> emission with increasing Mn<SUP>2+</SUP>-concentration in Na<SUB>2</SUB>CaMg(PO<SUB>4</SUB>)<SUB>2</SUB> were observed. The results are discussed in relation with the detailed crystal structure and the spectral analyses. The CIE coordinates and the luminescence decay (lifetimes) of Mn<SUP>2+</SUP> ions were discussed in order to further investigate the potential applications.</P> <P>Graphic Abstract</P><P>Na<SUB>2</SUB>CaMg<SUB>1−<I>x</I></SUB>Mn<SUB><I>x</I></SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> demonstrates the low-temperature monoclinic α-phase to the high-temperature trigonal β-phase transition and the red-shift of luminescence wavelength with increasing Mn<SUP>2+</SUP>-doping (<I>x</I> = 0.05–1.0). <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1jm12854j'> </P>

Investigation of muscle-specific beef color stability at different ultimate pHs

Wu Shuang,Han Jina,Liang Rongrong,Dong Pengcheng,Zhu Lixian,Hopkins David L.,Zhang Yimin,Luo Xin 아세아·태평양축산학회 2020 Animal Bioscience Vol.33 No.12

Objective: This study was aimed to investigate the muscle-specific beef color stability at normal and high ultimate pHs. Methods: The impact of muscle (Longissimus lumborum [LL] vs psoas major [PM]) and pH (normal ultimate pH [Np] vs high pH dark cutting beef [Hp]) on color stability, indicated by basic color traits, metmyoglobin reducing activity (MRA) and oxygen consumption (OC), as well as the lipid oxidation, were determined over 7 days of display at 4°C. Results: Hp-LL had the highest pH (6.92), followed by Hp-PM (6.01), Np-PM (5.76), and Np-LL (5.52). Hp-LL had increased (p<0.05) a*, chroma and % oxymyoglobin during display. Hp-LL also had the highest metmyoglobin (MMb) reducing activity and OC among all the samples, thus, the greatest color stability, although very dark throughout storage, with lowest values for lightness (L*) and yellowness (b*). Np-LL also exhibited relatively high color stability, as a result of its lower % MMb and OC and higher MRA than psoas muscle samples. The 0.2 unit difference of the pH between Hp and Np psoas muscle, resulted in the difference of the color intensity, not the color stability. Interestingly, high pH psoas muscle (Hp-PM) did not have better color stability than Np-PM, and in fact had lower color stability than even Np-LL. The similar level of OC and lipid oxidation cannot explain the difference in color stability between Hp-PM and Np-LL. Conclusion: The Hp does not always show better color stability compared with Np beef, which depends on the muscle type. The balance of MRA and OC is important to keep the color in great intensity and stability in the meantime.

Temperature-Dependent Photoluminescence from ZnO/Zn0.85Mg0.15O Heterostructure Grown on Si(111) Substrates

L. P. Zhu,X. Q. Gu,H. P. He,F. Huang,M. X. Qiu,Z. Z. Ye,Y. Z. Zhang,B. H. Zhao 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.5

A ZnO/Zn0.85Mg0.15O single quantum well (SQW) was fabricated on a Si(111) substrate by using a pulsed laser deposition (PLD) technique. Photoluminescence (PL) measurements were carried out in the range of 10 − 290 K in order to investigate the mechanism of carrier dynamics. At 10 K, the sample exhibited two predominant ultraviolet emissions, one at 3.57 eV and the other at 3.38 eV, which were attributed to recombinations of localized excitons (LE band) in the barrier and the well layers, respectively. The quantum well emission showed a blue shift of nearly 20 meV with respect to the epitaxial ZnO films. We also observed that the carrier localization resulted in an “S-shaped” red-blue-red shift of the ∽3.38 eV emission with increasing temperature. A ZnO/Zn0.85Mg0.15O single quantum well (SQW) was fabricated on a Si(111) substrate by using a pulsed laser deposition (PLD) technique. Photoluminescence (PL) measurements were carried out in the range of 10 − 290 K in order to investigate the mechanism of carrier dynamics. At 10 K, the sample exhibited two predominant ultraviolet emissions, one at 3.57 eV and the other at 3.38 eV, which were attributed to recombinations of localized excitons (LE band) in the barrier and the well layers, respectively. The quantum well emission showed a blue shift of nearly 20 meV with respect to the epitaxial ZnO films. We also observed that the carrier localization resulted in an “S-shaped” red-blue-red shift of the ∽3.38 eV emission with increasing temperature.

Colloidal Suspension Properties of Carbonaceous Nanomaterials Enhanced by Using Li as Dopant

Zhu, L.,Meng, Z.-D.,Chen, M.-L.,Choi, J.-G.,Park, C.-Y.,Lee, S.-C.,Hong, D.-S.,Oh, W.-C. CHEMIC PUBLISHING COMPANY 2012 Asian Journal of Chemistry Vol.24 No.2

Effects of the Zr concentration on transparent Y2O3 ceramics fabricated by vacuum pre-sintering and a subsequent HIP treatment

Zhu, L. L.,Park, Y. J.,Gan, L.,Go, S. I.,Kim, H. N.,Kim, J. M.,Ko, J. W. Chapman and Hall 2017 Journal of materials science Materials in electron Vol. No.

<P>Highly transparent Y2O3 ceramics doped with different Zr concentrations were successfully fabricated by vacuum pre-sintering at temperatures ranging from 1600 to 1800 degrees C combined with a subsequent hot-isostatic pressing (HIP) treatment using commercial powders as the starting materials. All of the 1 mol% Zr-doped Y2O3 ceramics exhibit very good optical quality. The sample with the highest transparency level was realized by vacuum sintering at 1650 degrees C for 4 h followed by a post-HIP treatment at 1450 degrees C lasting 5 h. It has a fine microstructure and the grain size is 1.48 mu m. Furthermore, the in-line transmittance reaches 83.3% at 1100 nm (1.2 mm thickness). It was found that a relatively low vacuum sintering temperature (1650 degrees C) and relatively low Zr doping concentration (1 mol%) are more appropriate to achieve optimally transparent Y2O3 ceramics with a subsequent HIP treatment.</P>

Enhancement of Dispersion, Thermophysical and Electrical Properties of Metals (Na, Al, Li) Treated Water Based Carbon Nanofluids

Zhu, L.,Meng, Z.-D.,Chen, M.-L.,Choi, J.-G.,Park, C.-Y.,Lee, S.-C.,Hong, D.-S.,Lee, J.-G.,Oh, W.-C. CHEMIC PUBLISHING COMPANY 2012 Asian journal of chemistry Vol.24 No.2

Rapid sonochemical synthesis of novel PbSe-graphene-TiO₂ composite sonocatalysts with enhanced on decolorization performance and generation of ROS

Zhu, L.,Chung, J.d.,Oh, W.C. Elsevier Science 2015 Ultrasonics sonochemistry Vol.27 No.-

Nanostructured PbSe-graphene-TiO<SUB>2</SUB> composites have been successfully synthesized via a facile ethylene glycol assisted-sonochemical synthesis approach in an aqueous solution. The as-prepared PbSe-graphene-TiO<SUB>2</SUB> composites possessed enhanced decolorization of rhodamine B (Rh.B) and industrial dyes such as Texbrite BA-L (TBA), extended light absorption range, and efficient charge separation properties simultaneously. And the generation of reactive oxygen species (ROS) was detected through the oxidation reaction from 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). The sono-catalytic reaction mechanism was investigated by analyzing the date obtained. The coated PbSe and TiO<SUB>2</SUB> nanoparticles with small and good dispersion station could be related to the sonochemical assisted synthesis route, it is wished that this paper might offer some important subjects for broadening the applications of sonocatalytic technologies.

OGLE-2016-BLG-1469L: Microlensing Binary Composed of Brown Dwarfs

Han, C.,Udalski, A.,Sumi, T.,Gould, A.,Albrow, M. D.,Chung, S.-J.,Jung, Y. K.,Ryu, Y.-H.,Shin, I.-G.,Yee, J. C.,Zhu, W.,Cha, S.-M.,Kim, S.-L.,Kim, D.-J.,Lee, C.-U.,Lee, Y.,Park, B.-G.,Soszyń,ski, American Astronomical Society 2017 The Astrophysical journal Vol.843 No.1

<P>We report the discovery of a binary composed of two brown dwarfs, based on the analysis of the microlensing event OGLE-2016-BLG-1469. Thanks to the detection of both finite-source and microlens-parallax effects, we are able to measure both the masses M-1 similar to 0.05M(circle dot) and. M-2 similar to 0.01M(circle dot), and the. distance D-L similar to 4.5 kpc, as well as the projected separation a(perpendicular to) similar to 0.33 au. This is the third brown-dwarf binary detected using the microlensing method, demonstrating the usefulness of microlensing in detecting field brown-dwarf binaries with separations of less than 1 au.</P>

CIRCUMBINARY PLANETS ORBITING AROUND POST COMMON ENVELOPE BINARIES

ZHU, L.Y.,QIAN, S.B.,LIAO, W.P.,LAJUS, E. FERNANDEZ,SOONTHORNTHUM, B.,ZHAO, E.G.,LIU, L. The Korean Astronomical Society 2015 天文學論叢 Vol.30 No.2

Most of the stars in the Galaxy are in binary systems. Binaries should be possible as the hosting stars of planets. Searching for planetary companions to binaries, especially evolved close binary stars, can provide insight into the formation and the ultimate fate of circumbinary planets and shed light on the late evolution of binary stars. In order to do this, we have chosen some post common envelope binaries including sdB-type eclipsing binaries and detached WD+dM eclipsing binaries as our targets and monitored them for several years. In this paper, we will present some of our new observations and results for three targets, NSVS 07826147, NSVS14256825 and RR Cae.

Effect of γ-Aminobutyric Acid-producing Lactobacillus Strain on Laying Performance, Egg Quality and Serum Enzyme Activity in Hy-Line Brown Hens under Heat Stress

Zhu, Y.Z.,Cheng, J.L.,Ren, M.,Yin, L.,Piao, X.S. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.7

Heat-stress remains a costly issue for animal production, especially for poultry as they lack sweat glands, and alleviating heat-stress is necessary for ensuring animal production in hot environment. A high ${\gamma}$-aminobutyric acid (GABA)-producer Lactobacillus strain was used to investigate the effect of dietary GABA-producer on laying performance and egg quality in heat-stressed Hy-line brown hens. Hy-Line brown hens (n = 1,164) at 280 days of age were randomly divided into 4 groups based on the amount of freeze-dried GABA-producer added to the basal diet as follows: i) 0 mg/kg, ii) 25 mg/kg, iii) 50 mg/kg, and iv) 100 mg/kg. All hens were subjected to heat-stress treatment through maintaining the temperature and the relative humidity at $28.83{\pm}3.85^{\circ}C$ and 37% to 53.9%, respectively. During the experiment, laying rate, egg weight and feed intake of hens were recorded daily. At the 30th and 60th day after the start of the experiment, biochemical parameters, enzyme activity and immune activity in serum were measured. Egg production, average egg weight, average daily feed intake, feed conversion ratio and percentage of speckled egg, soft shell egg and misshaped egg were significantly improved (p<0.05) by the increasing supplementation of the dietary GABA-producer. Shape index, eggshell thickness, strength and weight were increased linearly with increasing GABA-producer supplementation. The level of calcium, phosphorus, glucose, total protein and albumin in serum of the hens fed GABA-producing strain supplemented diet was significantly higher (p<0.05) than that of the hens fed the basal diet, whereas cholesterol level was decreased. Compared with the basal diet, GABA-producer strain supplementation increased serum level of glutathione peroxidase (p = 0.009) and superoxide dismutase. In conclusion, GABA-producer played an important role in alleviating heat-stress, the isolated GABA-producer strain might be a potential natural and safe probiotic to use to improve laying performance and egg quality in heat-stressed hens.