Surface properties and memory effect: Key factors in determining the catalytic efficiency of sulfated zirconia

Two series of sulfated zirconia catalysts were synthesized from various precursors using mono- or multi-step sequence preparations under laboratory conditions. Their activities/selectivities in the isomerization reaction of n-hexane were correlated to their textural, structural and morphological properties. The slightly higher activity of a commercially sulfated Zr(OH)4-based catalyst is in agreement with the differences in the content of SO24 - ions and their thermal stability, textural and structural properties, i.e., crystallite size and possible imperfection of the incorporation of sulfate groups in the multi-step synthesis of the catalyst having a nitrate origin. The employment of H2 as the carrier gas resulted in no catalytic activity, regardless of the catalyst precursor, preparation method and calcination temperature. When the isomerization reaction was performed under He, the relatively short life-times of all catalyst samples were caused by fast deactivation due to coking in the absence of H2. .

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Influences of Mg Doping on the Electrochemical Performance of TiO2Nanodots Based Biosensor Electrodes

Advances in Materials Science and Engineering ◽

10.1155/2014/965821 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

M. S. H. Al-Furjan ◽

Kui Cheng ◽

Wenjian Weng

Keyword(s):

Electron Transfer ◽

Spin Coating ◽

Direct Electron Transfer ◽

Catalytic Efficiency ◽

Key Factors ◽

Enzyme Adsorption ◽

Adsorption Ability ◽

Mg Doping ◽

And Performance ◽

Mg Doped

Electrochemical biosensors are essential for health monitors to help in diagnosis and detection of diseases. Enzyme adsorptions on biosensor electrodes and direct electron transfer between them have been recognized as key factors to affect biosensor performance. TiO2has a good protein adsorption ability and facilitates having more enzyme adsorption and better electron transfer. In this work, Mg ions are introduced into TiO2nanodots in order to further improve electrode performance because Mg ions are considered to have good affinity with proteins or enzymes. Mg doped TiO2nanodots on Ti substrates were prepared by spin-coating and calcining. The effects of Mg doping on the nanodots morphology and performance of the electrodes were investigated. The density and size of TiO2nanodots were obviously changed with Mg doping. The sensitivity of 2% Mg doped TiO2nanodots based biosensor electrode increased to 1377.64 from 897.8 µA mM−1 cm−2and itsKMappdecreases to 0.83 from 1.27 mM, implying that the enzyme achieves higher catalytic efficiency due to better affinity of the enzyme with the Mg doped TiO2. The present work could provide an alternative to improve biosensor performances.

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Tailoring the surface properties of Ni/SiO2 catalyst with sulfuric acid for enhancing the catalytic efficiency for steam reforming of guaiacol

Renewable Energy ◽

10.1016/j.renene.2020.04.012 ◽

2020 ◽

Vol 156 ◽

pp. 423-439 ◽

Cited By ~ 1

Author(s):

Zhanming Zhang ◽

Lijun Zhang ◽

Fang Liu ◽

Yifan Sun ◽

Yuewen Shao ◽

...

Keyword(s):

Sulfuric Acid ◽

Surface Properties ◽

Steam Reforming ◽

Catalytic Efficiency

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Precursor type affecting surface properties and catalytic activity of sulfated zirconia

Acta periodica technologica ◽

10.2298/apt0738105z ◽

2007 ◽

pp. 105-113 ◽

Cited By ~ 1

Author(s):

Aleksandra Zarubica ◽

Goran Boskovic

Keyword(s):

Catalytic Activity ◽

Beneficial Effect ◽

Surface Properties ◽

Sulfated Zirconia ◽

Tetragonal Phase ◽

Catalyst Activity ◽

Sol Gel ◽

Surface Characteristics ◽

Zirconium Hydroxide ◽

Catalytic Activities

Zirconium-hydroxide precursor samples are synthesized from Zr-hydroxide, Zr-nitrate, and Zr-alkoxide, by precipitation/impregnation, as well as by a modified sol-gel method. Precursor samples are further sulphated for the intended SO4 2- content of 4 wt.%, and calcined at 500-700oC. Differences in precursors? origin and calcination temperature induce the incorporation of SO4 2- groups into ZrO2 matrices by various mechanisms. As a result, different amounts of residual sulphates are coupled with other structural, as well as surface properties, resulting in various catalytic activities of sulphated zirconia samples. Catalyst activity and selectivity are a complex synergistic function of tetragonal phase fraction, sulphates contents, textural and surface characteristics. Superior activity of SZ of alkoxide origin can be explained by a beneficial effect of meso-pores owing to a better accommodation of coke deposits.

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Characteristics of Anodized Layer in Investment Cast Ni50Ti50 Shape Memory Alloy

Journal of Metallurgy ◽

10.1155/2014/346328 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Shimaa H. El-Hadad ◽

Khaled M. Ibrahim ◽

Lothar Wagner

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Oxide Layer ◽

Surface Properties ◽

Shape Memory Effect ◽

Memory Effect ◽

Investment Casting ◽

Biological Application ◽

Investment Cast ◽

Niti Shape Memory Alloys

NiTi shape memory alloys are promising implant materials due to their shape memory effect and super elasticity. In the current study, some Ni50Ti50 (mass %) SMAs samples were prepared by investment casting. These samples were then anodized and thermally treated to improve the surface properties. A fully saturated oxide layer was obtained. The structure and hardness properties of the anodized surfaces were then investigated. A hard porous layer with no free Ni atoms could be obtained which can be used as prebiomimetic surface for biological application.

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Biological and Surface Properties of C-Type Virus Particles Produced by Novikoff Ascites Hepatoma Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079395 ◽

1977 ◽

Vol 35 ◽

pp. 388-389

Author(s):

D.C. Hixson ◽

J.C. Chan ◽

J.M. Bowen ◽

E.F. Walborg

Keyword(s):

Surface Properties ◽

Ricinus Communis ◽

Rat Kidney ◽

Leukemia Virus ◽

Viral Envelope ◽

Virus Particles ◽

Chemically Induced ◽

Sarcoma Virus ◽

Hepatocarcinoma Cells ◽

Type C

Several years ago Karasaki (1) reported the production of type C virus particles by Novikoff ascites hepatocarcinoma cells. More recently, Weinstein (2) has reported the presence of type C virus particles in cell cultures derived from transplantable and primary hepatocellular carcinomas. To date, the biological function of these virus and their significance in chemically induced hepatocarcinogenesis are unknown. The present studies were initiated to determine a possible role for type C virus particles in chemically induced hepatocarcinogenesis. This communication describes results of studies on the biological and surface properties of type C virus associated with Novikoff hepatocarcinoma cells.Ecotropic and xenotropic murine leukemia virus (MuLV) activity in ascitic fluid of Novikoff tumor-bearing rats was assayed in murine sarcoma virus transformed S+L- mouse cells and S+L- mink cells, respectively. The presence of sarcoma virus activity was assayed in non-virus-producing normal rat kidney (NRK) cells. Ferritin conjugates of concanavalin A (Fer-Con wheat germ agglutinin (Fer-WGA), and Ricinus communis agglutinins I and II (Fer-RCAI and Fer-RCAII) were used to probe the structure and topography of saccharide determinants present on the viral envelope.

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