Zibo, China
Zibo, China

Time filter

Source Type

Zhang L.,Wan Jie Group CO. | Zhang L.,Shandong University of Technology | Yu X.,Shandong University of Technology | Zhang H.,Shandong University of Technology | And 2 more authors.
Journal of Radioanalytical and Nuclear Chemistry | Year: 2013

In this work, a naturally occurring illite was characterized by using FT-IR and XRD technique to determine its surface functional groups and crystal structure. Sorption of 60Co(II) on illite as a function of contact time, pH, ionic strength, foreign ions, humic substances and temperature was studied under ambient condition using batch technique. The results indicated that the sorption of 60Co(II) on illite is strongly affected by pH values (2-9) and ionic strength. A positive effect of humic substances on 60Co(II) sorption was found at pH < 7.0, whereas a negative effect was observed at pH > 7.0. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation and ion exchange with Na +/H+ on illite surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir and Freundlich models were used to simulate the sorption isotherms of 60Co(II) at three different temperatures of 298.15, 323.15 and 343.15 K. The thermodynamic parameters (ΔH 0, ΔS 0 and ΔG 0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 60Co(II) on illite was endothermic and spontaneous. © 2012 Akadémiai Kiadó, Budapest, Hungary.

Yang P.,University of Jinan | Zhang L.,Wan Jie Group Co. | Li X.,University of Jinan | Zhang Y.,University of Jinan | And 2 more authors.
Journal of Non-Crystalline Solids | Year: 2012

Multi hydrophobic CdSe/ZnS or CdSe/Cd xZn 1 - xS quantum dots were encapsulated into SiO 2 beads through a three-step sol-gel procedure. First, the quantum dots were transferred from toluene to water phase via silanization using tetraethyl orthosilicate. The control of ligand exchange (partially hydrolyzed tetraethyl orthosilicate instead of organic amine) resulted in the quantum dots retaining their initial photoluminescence efficiencies after the phase transfer. Second, the assembly of the quantum dots occurs by the hydrolysis and condensation of tetraethyl orthosilicate to form seeds. The amount of 3-mercaptopropyltrimethoxysilane during incorporation plays an important role in controlling the quantum dot number per seed. Third, the seeds are coated with a SiO 2 shell by a subsequent Stöber process. The resulting SiO 2 beads with a controlled number of hydrophobic quantum dots revealed high photoluminescence efficiency. The SiO 2 beads were functionalized with amine, carboxyl, and thiol-terminated biolinkers for surface modification. To confirm the surface modification by carboxyl groups, the SiO 2 beads were conjugated with amino functional polystyrene beads. The silica beads introduced here represent a new platform for nanoparticulate multimodality bioanalysis. © 2012 Elsevier B.V.

Yang P.,University of Jinan | Wang Y.,University of Jinan | Zhang L.,Wan Jie Group Co.
Journal of Nanoscience and Nanotechnology | Year: 2013

Luminescent CdSe/Cd0.5Zn0.5S quantum dots (QDs) with narrow size distribution and high photoluminescence (PL) efficiency were fabricated via a two-step organic synthesis. The QDs were coated with a SiO 2 shell by a reverse micelle route. The thickness of SiO2 shell on the QDs was adjusted for investigating the effect of the porous structure of SiO2 matrix on the stability of the QDs. When the shell thickness of SiO2 shells is less than 5 nm, the pores of SiO 2 shell are type II (cylindrical pores). In contrast, the pores of SiO2 shell are type IV (one-neck-flask-shaped pores) while the shell thickness is 10 nm. The stability of SiO2-coated QDs was investigated in phosphate-buffered saline (PBS, pH ~ 7.4) buffer solutions using various phosphate concentrations. The QDs coated with a SiO2 shell with type IV pores revealed high stability compared with those with type II pores. This is ascribed that cylindrical pores (type II) accelerated the transfer of ions in SiO2 shells compared with type IV pores. Copyright © 2013 American Scientific Publishers.

Yang F.,University of Jinan | Yang P.,University of Jinan | Zhang L.,Wan Jie Group Co.
Luminescence | Year: 2013

We exploited the synthesis of near-infrared (NIR) emitting ternary-alloyed CdTeSe and quaternary-alloyed CdZnTeSe quantum dots (QDs) with rod and tetrapod morphologies, which have tunable emission in the NIR electromagnetic spectrum. The morphologies of the QDs depended strongly on their growth kinetics, probably due to the coordinating ligands used in the preparation. Using oleic acid, stearic acid and hexadecylamine as ligands and keeping the same reaction parameters, QDs with tetrapod and rod morphologies were created. Not only had the capping ligands influenced the morphologies of QDs, but also they influenced the optical properties of QDs. The molar ratios of Cd/Zn and Te/Se upon preparation were adjusted for investigating the effect of composition on the properties of resulting QDs. By varying the composition of QDs, the photoluminescence (PL) wavelength of QDs was tuned from 650 nm to 800 nm. To enhance PL efficiency and stability, QDs were coated with a CdZnS shell. As NIR PL has numerous advantages in biological imaging detection, these QDs hold great potential for application. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

Zhang Y.,University of Jinan | Yang P.,University of Jinan | Zhang L.,Wan Jie Group Co.
Materials Chemistry and Physics | Year: 2013

We developed a facile method (a polyol synthesis) to prepare uniform silver nanostructures with various morphologies using ethylene glycol (EG) reduction of silver nitrate at 120 °C in the presence of poly(vinyl pyrrolidone) (PVP) and NaCl. Ag rods were fabricated by simply aging the freshly prepared AgNO3 solution with PVP, EG, and NaCl under ambient atmosphere without changing other parameters. The formation and degradation of the rods were systematically investigated. The result indicates that twinned-crystal seeds play an important role for the growth of anisotropic Ag rods. The NaCl concentration in solutions affected the formation of the rod. The rod was degraded subsequently via an etching process of O2/Cl (NaCl), resulting in the formation of Ag nanostructures with various shapes. Twinned Ag seeds in solutions were etched by increasing the concentration of NaCl, yielding uniform Ag cubes. Regular Ag cubes were fabricated under optimal preparation conditions. Ag cubes with various sizes (150-600 nm) were created by adjusting PVP concentrations in solutions. © 2013 Elsevier B.V. All rights reserved.

Mu J.C.,Shandong University of Technology | Zhang L.P.,Wan Jie Group Co.
Advanced Materials Research | Year: 2011

The cermets were prepared for aluminum electrolysis as inert anode. The microstructure of cermets inter anode was dense , the crystal of cermets growth ideally. The electric conductivity was stable and good, had the electric conductivity property of the semiconductor. The conductivity increased with temperature increasing. Electrolysis was conducted 12h at 850°C in cryolite molten salt(CR=2.0, Al2O3comtent 5.0% ), and the anodic current density was 1.0 A/cm2.The results showed that the cermets inert anode had high anti-oxidation, corrosion resistance and high conductivity. The back electromotive force was 2.45V, the decomposition voltage was 2.18V, the conductivity at 850°C was 47S/cm, the annual corrosion rate was 23.68 mm/year. © (2011) Trans Tech Publications.

Hua J.-J.,CAS Shanghai Institute of Ceramics | Zhang L.-P.,Wan Jie Group CO. | Liu Z.-W.,CAS Shanghai Institute of Ceramics | Wang Y.-Z.,CAS Shanghai Institute of Ceramics | And 3 more authors.
Wuji Cailiao Xuebao/Journal of Inorganic Materials | Year: 2012

Thermal barrier coatings (TBCs) is one of the important materials of turbines for propulsion and power generation with excellent thermal insulation properties. At high temperature, the failure of TBCs will lead to serious problems, so the failure mechanisms is the hotspot of TBCs research. The microcracks caused by thermal stress and the TGO formation and growth will cause the failure of TBCs. The whole failure progress, such as the oxidation of the BC, the TGO growth process, initiation and propagation of the microcracks are reviewed in this paper. The factors led to the final failure are discussed, and the recent research progress on improving the lifetime of TBCs is summarized. In addition, the trend of the failure mechanism of thermal barrier coatings is described.

Zhang Y.,University of Jinan | Yang P.,University of Jinan | Zhang L.,Wan Jie Group Co.
Journal of Nanoscience and Nanotechnology | Year: 2012

Triangular Ag nanoplates were prepared via a one-pot synthesis method by using citrate and poly (vinyl pyrolidone) (PVP). The edge length of the nanoplates was changed from 30 nm to 100 nm with increasing the concentration of PVP and the amount of sodium borohydride in aqueous solutions during preparation. The molar ratio of PVP to Ag nitrate affected the morphologies of the nanoplates. PVP plays an important role for determining the final morphologies and edge length of resulting nanoplates because the amount of PVP affected the viscosity of solutions. The viscosity of solutions kinetically controlled the nucleation and growth of Ag nanoplates. Furthermore, Ag nanoplates were not created in the case of without PVP. After adding sodium chloride, irregular Ag nanoparticles (NPs) instead of nanoplates were fabricated because of a Cl-/O2 etching process. Stacking fault was a key for the growth of triangular nanostructures. Reaction temperature and aging time also affected the formation of Ag nanoplates. Copyright © 2012 American Scientific Publishers.

Yang P.,University of Jinan | Zhang L.,Wan Jie Group Co. | Wang Y.,University of Jinan
Journal of Nanoscience and Nanotechnology | Year: 2012

A sol-gel method has been developed to fabricate functional silica film with Au/SiO2/quantum dot (QD) core/shell/shell nanostructures which exhibited plasmonic enhanced photoluminescence (PL). Au nanoparticles (NPs) were homogeneously coated with a SiO2 shell by an optimal Stöber synthesis. Hydrophobic CdSe/ZnS QDs was transferred into water phase via a ligand exchange by a thin functional SiO2 layer consisted of partially hydrolyzed 3-aminopropyltrimethoxysilane (APS) sol. The Au/SiO 2/QD core/shell/shell nanostructure was created by assembling the functional SiO2-coated QDs to the SiO2-coated Au NPs while QDs transferred into water phase. Those partially hydrolyzed APS molecules play an important role for the connection between the QDs and SiO2-coated Au NPs. The Au/SiO2/QD core/shell/shell nanostructures were embedded in functional sol-gel SiO2 films fabricated via spinning and dipping coating, in which the film revealed strong surface plasmon scattering and enhanced PL. Because of the dual functionality, the film is utilizable for various applications including biological and medical sensors, optical devices, and solar cells. This technique can serve as a general route for encapsulating a variety of nanomaterials in sol-gel films. Copyright © 2012 American Scientific Publishers All rights reserved.

Zhang Y.,University of Jinan | Yang P.,University of Jinan | Zhang L.,Wan Jie Group Co.
Journal of Nanoparticle Research | Year: 2013

Growth of silver nanoparticles (NPs) with a size ranging from of 6 ± 0.8-42 ± 1.6 nm was investigated systematically by the NaBH4 reduction of silver nitrate using citrate and poly (vinyl pyrrolidone) (PVP) as stabilizers through a facile one-pot aqueous synthesis. Because of controlling nucleation and growth processes, the NPs revealed narrow size distribution. Citrate and NaCl play important roles for the NPs with spherical morphology because of the adsorption of C6H5O7 3-on the {111} facet of silver particles and the etching of Cl -/O2. The addition of PVP resulted in the NPs small size and narrow size distribution. Spherical Ag NPs cannot be acquired by such one-pot reduction method in the absence of sodium citrate and NaCl, indicating the poor balance between the nucleation and growth processes in the reactions. On the basis of the results, reduction of the silver precursor (Ag+) was promoted with sodium citrate, attributed to the higher activity of the citrate reductant. The selective adsorption role of C6H 5O7 3- and PVP on the {111} plane, in addition to the stacking fault of {111} plane, led to silver atoms in the reaction solution deposited on {111} facet in the absence of NaCl, and then formed triangular silver nanoplates. © 2012 Springer Science+Business Media Dordrecht.

Loading Wan Jie Group Co. collaborators
Loading Wan Jie Group Co. collaborators