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Dual-sensing porphyrin-containing copolymer nanosensor as full-spectrum colorimeter and ultra-sensitive thermometer

Dual-sensing porphyrin-containing copolymer nanosensor as full-spectrum colorimeter and ultra-sensitive thermometer: "


Qiang Yan, Jinying Yuan, Yan Kang, Zhinan Cai, Lilin Zhou, Yingwu Yin

(Communication from Chem. Commun.)

Qiang Yan, Chem. Commun., 2010, DOI: 10.1039/b926882k

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Shape Effects of Cu2O Polyhedral Microcrystals on Photocatalytic Activity

Shape Effects of Cu2O Polyhedral Microcrystals on Photocatalytic Activity: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Mechanical characteristics of pure Mg and a Mg/Y2O3 nanocomposite in the 25–250 °C temperature range

Mechanical characteristics of pure Mg and a Mg/Y2O3 nanocomposite in the 25–250 °C temperature range: "

Abstract
In this study, the effect of nano-yttrium oxide particles on the mechanical properties of pure magnesium at elevated temperatures
is investigated. Mg/Y2O3 (2 wt%/0.7 vol%) bulk composite was synthesised via a powder metallurgy technique incorporating microwave sintering and hot
extrusion. Tensile properties and Brinell hardness behavior of pure Mg and composite samples in the 25–250 °C temperature
range were investigated. Both tensile and yield strengths of pure Mg and Mg/Y2O3 composite samples decreased with an increase in testing temperature. The elongation to failure, however, increased up to
200 °C. At all temperatures, the overall mechanical response of the composite samples was found to be superior compared to
pure magnesium and this is primarily attributed to the presence of Y2O3 particles in the magnesium matrix.


  • Content Type Journal Article
  • DOI 10.1007/s10853-010-4312-z
  • Authors

    • Ashis Mallick, National University of Singapore Department of Mechanical Engineering 9 Engineering Drive 1 Singapore 117576 Singapore
    • Khin Sandar Tun, National University of Singapore Department of Mechanical Engineering 9 Engineering Drive 1 Singapore 117576 Singapore
    • Srikanth Vedantam, National University of Singapore Department of Mechanical Engineering 9 Engineering Drive 1 Singapore 117576 Singapore
    • Manoj Gupta, National University of Singapore Department of Mechanical Engineering 9 Engineering Drive 1 Singapore 117576 Singapore


"

Wednesday, February 24, 2010

Synthesis of Monodisperse PbSe Nanorods: A Case for Oriented Attachment

Synthesis of Monodisperse PbSe Nanorods: A Case for Oriented Attachment: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

An Age-Old Printing Process Goes Nano

An Age-Old Printing Process Goes Nano: "ACS Nano, Volume 4, Issue 2, Page 595-598, February 23, 2010."

Monday, February 22, 2010

Tailored Synthesis of Superparamagnetic Gold Nanoshells with Tunable Optical Properties

Tailored Synthesis of Superparamagnetic Gold Nanoshells with Tunable Optical Properties: "Multifunctional Au nanoshells with tunable optical properties and fast magnetic response have been fabricated through a sequence of sol-gel, surface-protected etching, and seed-mediated growth processes. The use of a porous silica layer enhances the uniformity of nanoshell growth, the reproducibility of the synthesis, and the structural and optical stability of the products."

Sunday, February 21, 2010

Annealing temperature dependence of effective piezoelectric coefficients for Bi3.15Eu0.85Ti3O12 thin films

Annealing temperature dependence of effective piezoelectric coefficients for Bi3.15Eu0.85Ti3O12 thin films: "

Abstract
The effects of annealing temperatures 600, 650, 700, and 750 °C on microstructure, chemical composition, leakage current,
ferroelectric, dielectric, and piezoelectric properties of Bi3.15Eu0.85Ti3O12 (BET) thin films prepared by metal–organic decomposition were studied in detail. The largest spontaneous polarization 2P
s (98.7 μC/cm2 under 300 kV/cm), remnant polarization 2P
r (81.7 μC/cm2 under 300 kV/cm), dielectric constant εr (889.4 at 100 kHz), effective piezoelectric coefficient d
33 (46.7 pm/V under 260 kV/cm), and lowest leakage current (1.3 × 10−6 A/cm2 under 125 kV/cm) of BET thin film were obtained with annealing at 700 °C. The mechanisms concerning the dependence of the
enhancement d
33 are discussed according to the phenomenological equation, and the improved piezoelectric performance could make BET thin
film a promising candidate for piezoelectric thin film devices.


  • Content Type Journal Article
  • DOI 10.1007/s10853-010-4301-2
  • Authors

    • X. J. Zheng, Xiangtan University Faculty of Materials, Optoelectronics and Physics Xiangtan 411105 Hunan People’s Republic of China
    • Q. Y. Wu, Xiangtan University Faculty of Materials, Optoelectronics and Physics Xiangtan 411105 Hunan People’s Republic of China
    • J. F. Peng, Xiangtan University Faculty of Materials, Optoelectronics and Physics Xiangtan 411105 Hunan People’s Republic of China
    • L. He, Xiangtan University Faculty of Materials, Optoelectronics and Physics Xiangtan 411105 Hunan People’s Republic of China
    • X. Feng, Tsinghua University School of Aerospace Beijing 100084 People’s Republic of China
    • Y. Q. Chen, Xiangtan University Faculty of Materials, Optoelectronics and Physics Xiangtan 411105 Hunan People’s Republic of China
    • D. Z. Zhang, Xiangtan University Faculty of Materials, Optoelectronics and Physics Xiangtan 411105 Hunan People’s Republic of China


"

Saturday, February 20, 2010

Synthesis of TiO2 nanorods by oriented attachment using EDTA modifier: a novel approach towards 1D nanostructure development

Synthesis of TiO2 nanorods by oriented attachment using EDTA modifier: a novel approach towards 1D nanostructure development: "

Abstract
The synthesis of TiO2 nanorods with anatase structure has been achieved from the necking of truncated nanoparticles by oriented attachment using
titanium ethylenediaminetetraacetic acid (EDTA) chelated complex as a molecular precursor. The preparation was carried out
under mild conditions using a simple solvothermal process. The influence of EDTA over the growth of nanocrystallites and the
various other factors which contribute to the development of 1D TiO2 nanostructure are investigated. At a relatively lower temperature, titania nanopowders are obtained, and the anatase phase
crystallization is verified by wide angle X-ray diffraction. The evolution of rod-shaped TiO2 with tapered edges has been confirmed by transmission electron micrographs. The well aligned lattice fringes of TiO2 nanorod towards [001] direction is investigated by HRTEM. The SEM images show the surface configuration of overall aggregates
of titania crystallites consisted of primary particles which are densely packed in an orderly texture. The moderate shift
in the absorption band towards higher energy region of the absorption spectrum confirms the weak carrier confinement effect
in the sample.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-010-9877-6
  • Authors

    • P. Dennis Christy, Loyola College (Autonomous) Department of Physics Nungambakkam Chennai 600 034 India
    • N. Melikechi, Delaware State University Center for Research and Education in Optical Science and Applications, Department of Physics and Pre-engineering Dover DE 19901 USA
    • N. S. Nirmala Jothi, Loyola College (Autonomous) Department of Physics Nungambakkam Chennai 600 034 India
    • A. R. Baby Suganthi, Loyola College (Autonomous) Department of Physics Nungambakkam Chennai 600 034 India
    • P. Sagayaraj, Loyola College (Autonomous) Department of Physics Nungambakkam Chennai 600 034 India


"

Large-Scale Synthesis of Micrometer-Sized Silver Nanosheets

Large-Scale Synthesis of Micrometer-Sized Silver Nanosheets: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Optical properties of aluminophosphate glasses containing silver, tin, and dysprosium

Optical properties of aluminophosphate glasses containing silver, tin, and dysprosium: "

Abstract
The spectroscopic properties of a Dy3+-doped aluminophosphate glass containing silver and tin were reported. Different oxidation and aggregation states of silver
were obtained by varying silver concentration and glass thermal history. The addition of silver and tin at the lowest concentration
studied results in Dy3+ ions emission under nonresonant UV excitation in connection with the appearance of an excitation band around 270 nm, which
is associated to isolated Ag+ ions and twofold-coordinated Sn centers. The increase in silver and tin concentration leads to a broadening of aforementioned
band and to the presence of charged silver dimers as evidenced by the appearance of an excitation band around 330 nm. The
data indicated that light absorption might take place at ionic silver species and twofold-coordinated Sn centers, followed
by energy transfer to Dy3+ ions. After heat treatment, ionic silver species were reduced to atomic Ag by tin with the subsequent formation of Ag nanoparticles
(NPs) inside the dielectric host. A quenching effect in Dy3+ ions luminescence was shown with the presence of the Ag NPs, most notably for excitation of 6H15/24F9/2, 4I15/2, 4G11/2 transitions, which were in resonance with the dipole absorption mode of the particles. The silver NPs were believed to provide
radiationless pathways for excitation energy loss in Dy3+ ions.


  • Content Type Journal Article
  • DOI 10.1007/s10853-010-4297-7
  • Authors

    • J. A. Jiménez, University of Puerto Rico Department of Chemistry P.O. Box 9019 Mayagüez PR 00681-9019 USA
    • S. Lysenko, University of Puerto Rico Department of Physics P.O. Box 9016 Mayagüez PR 00681-9016 USA
    • H. Liu, University of Puerto Rico Department of Physics P.O. Box 9016 Mayagüez PR 00681-9016 USA


"

Fabrication and growth mechanism of hexagonal zinc oxide nanorods via solution process

Fabrication and growth mechanism of hexagonal zinc oxide nanorods via solution process: "

Abstract
This article presents, the fabrication of perfectly hexagonal zinc oxide nanorods performed via solution process using zinc
nitrate hexahydrate (Zn(NO3)2·6H2O) and hexamethylenetetramine (HMT) at various concentrations of i.e. 1 × 10−3 to 10 × 10−2 M in 50 mL distilled water and refluxed at 100 °C for 1 h. We used HMT because it acts as a template for the nucleation and
growth of zinc oxide nanorods, and it also works as a surfactant for the zinc oxide structures. The X-ray diffraction patterns
clearly reveal that the grown product is pure zinc oxide. The diameters and lengths of the synthesized nanorods lie in the
range of 200–800 nm and 2–4 μm, respectively as observed from the field emission scanning electron microscopy (FESEM). The
morphological observation was also confirmed by the transmission electron microscopy (TEM) and clearly consistent with the
FESEM observations. The chemical composition was analyzed by the FTIR spectroscopy, and it shows the ZnO band at 405 cm−1. On the basis of these observations, the growth mechanism of ZnO nanostructures was also proposed.


  • Content Type Journal Article
  • DOI 10.1007/s10853-010-4294-x
  • Authors

    • Rizwan Wahab, Chonbuk National University Energy Materials & Surface Science Laboratory, Solar Research Center, School of Chemical Engineering Jeonju 561-756 Republic of Korea
    • Young-Soon Kim, Chonbuk National University Energy Materials & Surface Science Laboratory, Solar Research Center, School of Chemical Engineering Jeonju 561-756 Republic of Korea
    • Kyeongseop Lee, Chonbuk National University Energy Materials & Surface Science Laboratory, Solar Research Center, School of Chemical Engineering Jeonju 561-756 Republic of Korea
    • Hyung-Shik Shin, Chonbuk National University Energy Materials & Surface Science Laboratory, Solar Research Center, School of Chemical Engineering Jeonju 561-756 Republic of Korea


"

Suppressed Blinking Dynamics of Single QDs on ITO

Suppressed Blinking Dynamics of Single QDs on ITO: "ACS Nano, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Optical manipulation of plasmonic nanoparticles, bubble formation and patterning of SERS aggregates

Optical manipulation of plasmonic nanoparticles, bubble formation and patterning of SERS
aggregates
: "Author(s): Zuwei Liu, Wei Hsuan Hung, Mehmet Aykol, David Valley and Stephen B Cronin
Affiliation(s): Department of Physics, University of Southern California, Los Angeles, CA 90089, USA; Department of Materials Science, University of Southern California, Los Angeles, CA 90089, USA; Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA; Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA"

Sunday, February 14, 2010

Study of tryptophan assisted synthesis of gold nanoparticles by combining UV–Vis, fluorescence, and SERS spectroscopy

Study of tryptophan assisted synthesis of gold nanoparticles by combining UV–Vis, fluorescence, and SERS spectroscopy: "

Abstract We developed a rapid and non-toxic method for the preparation of colloidal gold nanoparticles (GNPs) by using tryptophan (Trp)
as reducing/stabilizing agent. We show that the temperature has a major influence on the kinetics of gold ion reduction and
the crystal growth, higher temperatures favoring the synthesis of anisotropic nanoparticles (triangles and hexagons). The
as-synthesized nanostructures were characterized by UV–Vis absorption spectroscopy, transmission electron microscopy (TEM),
X-ray diffraction (XRD), fluorescence, and surface-enhanced Raman scattering (SERS) spectroscopy. The UV–Vis measurements
confirmed that temperature is a critical factor in the synthesis process, having a major effect on the shape of the synthesized
GNPs. Moreover, fluorescence spectroscopy was able to monitor the quenching of the Trp fluorescence during the in situ synthesis
of GNPs. Using Trp as molecular analyte to evaluate the SERS efficiency of as-prepared GNPs at different temperatures, we
demonstrated that the Raman enhancement of the synthesized gold nanoplates is higher than that of the gold spherical nanoparticles.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-010-9869-6
  • Authors

    • Monica Iosin, Babes-Bolyai University Nanobiophotonics Laboratory, Institute for Interdisciplinary Experimental Research Treboniu Laurian 42 400271 Cluj-Napoca Romania
    • Patrice Baldeck, Université Joseph Fourier, CNRS (UMR5588) Laboratoire de Spectrométrie Physique BP 87 38402 Saint Martin d’Hères France
    • Simion Astilean, Babes-Bolyai University Nanobiophotonics Laboratory, Institute for Interdisciplinary Experimental Research Treboniu Laurian 42 400271 Cluj-Napoca Romania


"

Superparamagnetic [gamma]-Fe2O3@SiO2 nanoparticles: a novel support for the immobilization of [VO(acac)2]

Superparamagnetic [gamma]-Fe2O3@SiO2 nanoparticles: a novel support for the immobilization of [VO(acac)2]: "


Clara Pereira, Andre M. Pereira, Pedro Quaresma, Pedro B. Tavares, Eulalia Pereira, Joao P. Araujo, Cristina Freire

(Paper from Dalton Trans.)

Clara Pereira, Dalton Trans., 2010, DOI: 10.1039/b920853d

To cite this article before page numbers are assigned, use the DOI form of citation above.


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Thursday, February 11, 2010

Luminescence in rare earth-doped transparent glass ceramics containing GdF3 nanocrystals for lighting applications

Luminescence in rare earth-doped transparent glass ceramics containing GdF3 nanocrystals for lighting applications: "

Abstract Rare earth ions-doped transparent glass ceramics containing hexagonal GdF3 nanocrystals with a mean size of 16 nm were prepared. Energy dispersive x-ray spectroscopy and luminescence spectrum investigation
evidenced the incorporation of rare earth ions into GdF3 nanocrystals. The efficient energy transfer from Gd3+ to Tb3+ was demonstrated in the Tb3+-doped glass ceramics, which resulted in an intense green light emission originated from Tb3+: 5D47F6 transition via the sensitization of Gd3+. Compared with the precursor glass, the Dy3+-doped glass ceramic exhibited longer lifetime and lower yellow-to-blue emission intensity ratio owing to the allocation of
Dy3+ ions in the low-phonon-energy GdF3 environment. Under ultraviolet excitation, the Dy3+-doped samples emitted bright white light, indicating their potential application in white light emitting diodes.


  • Content Type Journal Article
  • DOI 10.1007/s10853-010-4266-1
  • Authors

    • Zhifa Shan, Graduate University of Chinese Academy of Sciences State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 China
    • Daqin Chen, Graduate University of Chinese Academy of Sciences State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 China
    • Yunlong Yu, Graduate University of Chinese Academy of Sciences State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 China
    • Ping Huang, Graduate University of Chinese Academy of Sciences State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 China
    • Hang Lin, Graduate University of Chinese Academy of Sciences State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 China
    • Yuansheng Wang, Graduate University of Chinese Academy of Sciences State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 China


"

Tuesday, February 09, 2010

Controlled Synthesis of Uniform Silver Nanospheres†

Controlled Synthesis of Uniform Silver Nanospheres†: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Wednesday, February 03, 2010

Silver Nanocrystals: Self-Organization and Collective Properties

Silver Nanocrystals: Self-Organization and Collective Properties: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."