scholarly journals Osteoconductivity and Hydrophilicity of TiO2Coatings on Ti Substrates Prepared by Different Oxidizing Processes

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Dai Yamamoto ◽  
Ikki Kawai ◽  
Kensuke Kuroda ◽  
Ryoichi Ichino ◽  
Masazumi Okido ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Thermal Oxidation ◽  
Coating Process ◽  
Contact Ratio ◽  
Oxide Coatings ◽  
Hard Tissue ◽  
Water Contact ◽  
Oh Groups ◽  
Step Process ◽  
The Difference

Various techniques for forming TiO2coatings on Ti have been investigated for the improvement of the osteoconductivity of Ti implants. However, it is not clear how the oxidizing process affects this osteoconductivity. In this study, TiO2coatings were prepared using the following three processes: anodizing in 0.1 M H3PO4or 0.1 M NaOH aqueous solution; thermal oxidation at 673 K for 2 h in air; and a two-step process of anodizing followed by thermal oxidation. The oxide coatings were evaluated using SEM, XRD, and XPS. The water contact angle on the TiO2coatings was measured as a surface property. The osteoconductivity of these samples was evaluated by measuring the contact ratio of formed hard tissue on the implanted samples (defined as theRB-Ivalue) after 14 d implantation in rats' tibias. Anatase was formed by anodizing and rutile by thermal oxidation, but the difference in the TiO2crystal structure did not influence the osteoconductivity. Anodized TiO2coatings were hydrophilic, but thermally oxidized TiO2coatings were less hydrophilic than anodized TiO2coatings because they lacked in surface OH groups. The TiO2coating process using anodizing without thermal oxidation gave effective improvement of the osteoconductivity of Ti samples.

Rapid Biomimetic Coating of Calcium Phosphate on Titanium: Effect of Soaking Time, Temperature and Solution Refreshing

2016 ◽  
Vol 690 ◽  
pp. 81-86 ◽  
Author(s):  
Faungchat Thammarakcharoen ◽  
Jintamai Suwanprateeb
Keyword(s):  
Crystal Structure ◽  
Phase Composition ◽  
Calcium Phosphate ◽  
Octacalcium Phosphate ◽  
Solution Temperature ◽  
Phosphate Solution ◽  
Coating Process ◽  
Soaking Time ◽  
Biomimetic Coating ◽  
The Difference

The influence of employing three different solution temperatures (23, 37 and 50 °C), three soaking times (2, 4 and 6 h) and two solution refreshing methods (Refreshed or Non-refreshed) in rapid biomimetic coating process on phase composition, functional groups, coating content and microstructure of the resulted coating was studied. Increasing soaking times and temperature increased the coating content in all cases regardless of the use of refreshed or non-refreshed accelerated calcium phosphate solution. The use of non-refreshed solution resulted in the lower rate of coating than that of refreshed solution at all coating temperatures. However, all coatings similarly comprised octacalcium phosphate and hydroxyapatite as main phases and the microstructure consisted of sharp and interconnected plate-like crystals vertically grown on the surface of titanium. However, two types of crystal structure were produced. Low solution temperature resulted in isolated spheroids while uniform and distributed crystal structure was produced by using high solution temperature. This could be related to the difference in nucleation and precipitation rate formed in rapid biomimetic coating process as a result of the interplay between temperature and ionic strength of the solutions.

scholarly journals Ag-Functionalized Si Nanowire Arrays Aligned Vertically for SERS Detection of Captured Heavy Metal Ions by BSA

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 685
Author(s):  
Ai-Huei Chiou ◽  
Jun-Luo Wei ◽  
Ssu-Han Chen
Keyword(s):  
Heavy Metal ◽  
Raman Scattering ◽  
Metal Ions ◽  
Metal Ion ◽  
Heavy Metal Ions ◽  
Great Promise ◽  
Ag Nps ◽  
Water Contact ◽  
Oh Groups ◽  
Si Nanowire

A novel surface-enhanced Raman scattering (SERS)-based probe to capture heavy metal ion (Zn2+) by bovine serum albumin (BSA) using Si-nanowire (SiNW) arrays with silver nanoparticles (AgNPs) was developed. A layer with AgNPs was deposited on the SiNW surface by RF magnetron sputtering for enhancement of SERS signals. Using a high-resolution transmission electron microscope (HRTEM), the observation reveals that the AgNP layer with depths of 30–75 nm was successfully deposited on SiNW arrays. The Ag peaks in EDS and XRD spectra of SiNW arrays confirmed the presence of Ag particles on SiNW arrays. The WCA observations showed a high affinity of the Ag–SiNW arrays immobilized with BSA (water contact angle (WCA) = 87.1°) and ZnSO4 (WCA = 8.8°). The results of FTIR analysis illustrate that the conjugate bonds exist between zinc sulfate (ZnSO4) and –OH groups/–NH groups of BSA. The resulting SiNWs/Ag NPs composite interfaces showed large Raman scattering enhancement for the capture of heavy metal ions by BSA with a detection of 0.1 μM. BSA and ZnSO4 conjugations, illustrating specific SERS spectra with high sensitivity, which suggests great promise in developing label-free biosensors.

scholarly journals Generalization of intrinsic ductile-to-brittle criteria by Pugh and Pettifor for materials with a cubic crystal structure

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
O. N. Senkov ◽  
D. B. Miracle
Keyword(s):  
Crystal Structure ◽  
Shear Modulus ◽  
Bulk Modulus ◽  
Single Crystal ◽  
Elastic Constants ◽  
Mechanical Analysis ◽  
Quantum Mechanical ◽  
Modulus Ratio ◽  
Cubic Crystal ◽  
The Difference

AbstractTwo classical criteria, by Pugh and Pettifor, have been widely used by metallurgists to predict whether a material will be brittle or ductile. A phenomenological correlation by Pugh between metal brittleness and its shear modulus to bulk modulus ratio was established more than 60 years ago. Nearly four decades later Pettifor conducted a quantum mechanical analysis of bond hybridization in a series of intermetallics and derived a separate ductility criterion based on the difference between two single-crystal elastic constants, C12–C44. In this paper, we discover the link between these two criteria and show that they are identical for materials with cubic crystal structures.

scholarly journals Theoretical Study of the Structures of 4-(2,3,5,6-Tetrafluoropyridyl)Diphenylphosphine Oxide and Tris(Pentafluorophenyl)Phosphine Oxide: Why Does the Crystal Structure of (Tetrafluoropyridyl)Diphenylphosphine Oxide Have Two Different P=O Bond Lengths?

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2778
Author(s):  
Joseph R. Lane ◽  
Graham C. Saunders
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Phosphine Oxide ◽  
Density Functional ◽  
Lone Pair ◽  
Diphenylphosphine Oxide ◽  
Functional Theory ◽  
Weak Hydrogen Bonding ◽  
Independent Molecules ◽  
The Difference

The crystal structure of 4-(2,3,5,6-tetrafluoropyridyl)diphenylphosphine oxide (1) contains two independent molecules in the asymmetric unit. Although the molecules are virtually identical in all other aspects, the P=O bond distances differ by ca. 0.02 Å. In contrast, although tris(pentafluorophenyl)phosphine oxide (2) has a similar crystal structure, the P=O bond distances of the two independent molecules are identical. To investigate the reason for the difference, a density functional theory study was undertaken. Both structures comprise chains of molecules. The attraction between molecules of 1, which comprises lone pair–π, weak hydrogen bonding and C–H∙∙∙arene interactions, has energies of 70 and 71 kJ mol−1. The attraction between molecules of 2 comprises two lone pair–π interactions, and has energies of 99 and 100 kJ mol−1. There is weak hydrogen bonding between molecules of adjacent chains involving the oxygen atom of 1. For one molecule, this interaction is with a symmetry independent molecule, whereas for the other, it also occurs with a symmetry related molecule. This provides a reason for the difference in P=O distance. This interaction is not possible for 2, and so there is no difference between the P=O distances of 2.

Molecular orbital structures of sulfones

1982 ◽  
Vol 60 (6) ◽  
pp. 730-734 ◽  
Author(s):  
Russell J. Boyd ◽  
Jeffrey P. Szabo
Keyword(s):  
Crystal Structure ◽  
Gas Phase ◽  
Molecular Orbital ◽  
Geometry Optimization ◽  
Membered Ring ◽  
Molecular Orbital Calculations ◽  
Bond Lengths ◽  
Comparison With Experiment ◽  
The Difference

Abinitio molecular orbital calculations are reported for several cyclic and acyclic sulfones. The geometries of XSO2Y, where X, Y = H, F, or CH3 are optimized at the STO-3G* level. Similar calculations are reported for the smallest cyclic sulfone, thiirane-1,1 -dioxide, as well as the corresponding sulfoxide, thiirane-1-oxide, and the parent sulfide, thiirane. Where comparison with experiment is possible, the agreement is satisfactory. In order to consider the possibility of substantial differences between axial and equatorial S—O bonds in the gas phase, as observed in the crystal structure of 5H,8H-dibenzo[d,f][1,2]-dithiocin-1,1-dioxide, STO-3G* calculations are reported for a six-membered ring, thiane-1,1-dioxide, and a model eight-membered ring. Limited geometry optimization of the axial and equatorial S—O bonds in the chair conformations of the six- and eight-membered rings leads to bond lengths of 1.46 Å with the difference being less than 0.01 Å.

Three-step process for depositing indium-tin oxide coatings

1984 ◽  
Vol 23 (10) ◽  
pp. 1452 ◽  
Author(s):  
L. Assadourian ◽  
L. Herczeg
Keyword(s):  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Oxide Coatings ◽  
Step Process

scholarly journals Metallization of Carbon Fibers by Double and Triple Copper Composition

2015 ◽  
Vol 16 (1) ◽  
pp. 185-192
Author(s):  
H.O. Sirenko ◽  
M.B. Skladanyuk ◽  
L.M. Soltys
Keyword(s):  
Crystal Structure ◽  
Carbon Fibers ◽  
Copper Content ◽  
Coating Process ◽  
Carbon Fibres ◽  
Application Technology ◽  
Surface Layers ◽  
Foundations Of Physics ◽  
Theoretical Foundations ◽  
Layer Coating

The theoretical foundations of physics and chemistry and application technology of single- and double-layer coating based on Cu0+Cu2O, Ni0+P, Pb0 on the surface of carbonated fibers have been reviewed. The changes of surface layers crystal structure of carbon fibres in the course of copper-plating have been investigated. The metallic coating process using modified formaldehyde and zinc technology was realized. It is established that copper content in copper – copper oxide increases when using two-layer alternately modified formaldehyde and zinc methods.

scholarly journals Crystal structure of 2,6-bis(3-hydroxy-3-methylbut-1-yn-1-yl)pyridine monohydrate

2020 ◽  
Vol 76 (11) ◽  
pp. 1737-1740
Author(s):  
Take-aki Koizumi ◽  
Toshikazu Takata
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Pyridine Ring ◽  
Pyridine Molecule ◽  
Pyridine Derivative ◽  
Oh Groups

In the title pyridine derivative, C15H17NO2·H2O, the two OH groups are oriented in directions opposite to each other with respect to the plane of the pyridine ring. In the crystal, hydrogen bonds between the pyridine molecule and the water molecule, viz. Ohydroxy—H...Owater, Ohydroxy—H...Ohydroxy, Owater—H...Ohydroxy and Owater—H···Npyridine, result in the formation of a ribbon-like structure running along [011].

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