Effect of the salt melt composition, temperature, and interaction time on the contact exchange reaction in the MCl-PbCl2-MeN systems

Discs of TiAl6V4 were cleaned and stored in calcium containing salt melt. The characterization of the reaction layer was realized by TF-XRD, SEM, SIMS, AES, and eddy current. The release of Ca ions was determined after storing the samples in TRIS-HCl buffer solution under physiological conditions for at least 16 weeks. The thickness of the generated calcium titanate layer varied in dependence on salt melt composition, temperature, and storing time in the range of 0.4-0.9.m. The Ca content of the layer depends on melt composition, temperature and storing time and was in the range from 5-42.g●cm-2 in correlation with the thickness. The morphology of the layers also changed in dependence on the salt melt composition and the storing time and temperature.

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Pyridyl disulfide-based thiol–disulfide exchange reaction: shaping the design of redox-responsive polymeric materials

Polymer Chemistry ◽

10.1039/d0py01215g ◽

2020 ◽

Vol 11 (48) ◽

pp. 7603-7624

Author(s):

Ismail Altinbasak ◽

Mehmet Arslan ◽

Rana Sanyal ◽

Amitav Sanyal

Keyword(s):

Exchange Reaction ◽

Functional Materials ◽

Polymeric Materials ◽

Disulfide Exchange ◽

Redox Responsive ◽

Synthetic Approaches

This review provides an overview of synthetic approaches utilized to incorporate the thiol-reactive pyridyl-disulfide motif into various polymeric materials, and briefly highlights its utilization to obtain functional materials.

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Material Structure of Microcrystalline Silicon Deposited with an Expanding Thermal Plasma

MRS Proceedings ◽

10.1557/proc-762-a.15.3 ◽

2003 ◽

Vol 762 ◽

Cited By ~ 2

Author(s):

C. Smit ◽

D.L. Williamson ◽

M.C.M. van de Sanden ◽

R.A.C.M.M. van Swaaij

Keyword(s):

Thermal Plasma ◽

Hydrogen Plasma ◽

Plasma Chemistry ◽

Plasma Source ◽

Growth Direction ◽

Interaction Time ◽

Material Structure ◽

Average Particle ◽

Microcrystalline Silicon ◽

X Ray

AbstractExpanding thermal plasma CVD (ETP CVD) has been used to deposit thin microcrystalline silicon films. In this study we varied the position at which the silane is injected in the expanding hydrogen plasma: relatively far from the substrate and close to the plasma source, giving a long interaction time of the plasma with the silane, and close to the substrate, resulting in a short interaction time. The material structure is studied extensively. The crystalline fractions as obtained from Raman spectroscopy as well as from X-ray diffraction (XRD) vary from 0 to 67%. The average particle sizes vary from 6 to 17 nm as estimated from the (111) XRD peak using the Scherrer formula. Small angle X-ray scattering (SAXS) and flotation density measurements indicate void volume fractions of about 4 to 6%. When the samples are tilted the SAXS signal is lower than for the untilted case, indicating elongated objects parallel to the growth direction in the films. We show that the material properties are influenced by the position of silane injection in the reactor, indicating a change in the plasma chemistry.

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Metallographic analysis of M2 high speed steel granules

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2018-96-4-78-85 ◽

2019 ◽

pp. 78-85

Author(s):

L. E. Afanasieva

Keyword(s):

Solid Solution ◽

Cellular Structure ◽

High Speed ◽

Solution Structure ◽

Supersaturated Solid Solution ◽

High Speed Steel ◽

Metallographic Analysis ◽

M2 High Speed Steel ◽

Melt Composition

The article is devoted to the metallographic analysis of the M2 high-speed steel granules. The study is based on the investigation of the microstructure of the M2 high-speed steel granules obtained by melt atomization. It is demonstrated that granules of similar size can harden both by chemically separating and chemically non-separating mechanism. These last ones have supersaturated solid solution structure of the liquid melt composition, a dispersed dendritic-cellular structure and an increased microhardness HV = 10267±201 MPa.

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Photoassisted Production of O2-• and H2 in Aqueous Medium Stimulated by Polythiophene in ZSM-5 Zeolite Channels

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990149 ◽

1999 ◽

Vol 64 (1) ◽

pp. 149-156 ◽

Cited By ~ 7

Author(s):

Gabriel Čík ◽

František Šeršeň ◽

Alena Bumbálová

Keyword(s):

Reactive Oxygen Species ◽

Ion Exchange ◽

Visible Light ◽

Aqueous Medium ◽

Exchange Reaction ◽

Epr Spectroscopy ◽

Reactive Oxygen ◽

Oxygen Species ◽

Water Reduction ◽

Ion Exchange Reaction

The formation of reactive oxygen species due to irradiation by a visible light of the polythiophene deposited in ZSM-5 zeolite channels in aqueous medium has been studied. Polymerization of thiophene was carried out in zeolite channels after the ion-exchange reaction of Na+ for Fe3+. By means of EPR spectroscopy, the temporarily generated 1O2 in irradiated aqueous medium was proved. The formation of O2-• was confirmed by the reduction of Fe3+-cytochrome c. Irradiation led to the water reduction to hydrogen.

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Investigation of spatial ability test completion times in virtual reality using a desktop display and the Gear VR

Virtual Reality ◽

10.1007/s10055-021-00509-2 ◽

2021 ◽

Author(s):

Tibor Guzsvinecz ◽

Éva Orbán-Mihálykó ◽

Cecília Sik-Lányi ◽

Erika Perge

Keyword(s):

Virtual Reality ◽

Mental Rotation ◽

Spatial Ability ◽

Interaction Time ◽

Ability Test ◽

Ability Tests ◽

Hand Test ◽

The Relationship ◽

Completion Times ◽

Test Completion

AbstractThe interaction time of students who did spatial ability tests in a virtual reality environment is analyzed. The spatial ability test completion times of 240 and 61 students were measured. A desktop display as well as the Gear VR were used by the former group and by the latter one, respectively. Logistic regression analysis was used to investigate the relationship between the probability of correct answers and completion times, while linear regression was used to evaluate effects and interactions of following factors on test completion times: the users’ gender and primary hand, test type and device used. The findings were that while the completion times are not significantly affected by the users’ primary hand, other factors have significant effects on them: they are decreased by the male gender in itself, while they are increased by solving Mental Rotation Tests or by using the Gear VR. The largest significant increment in interaction time in virtual reality during spatial ability tests is when Mental Rotation Tests are accomplished by males with the Gear VR, while the largest significant decrease in interaction time is when Mental Cutting Tests are completed with a desktop display.

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