The effect of graphene oxide reduction temperature on the kinetics of low-temperature sorption of hydrogen

The course of the conversion of methanol with water vapour was followed on a low-temperature Cu-Zn-Cr-Al catalyst at pressures of 0.2 and 0.6 MPa. The kinetic data were evaluated together with those obtained at 0.1 MPa and the following equation for the reaction kinetics at the given conditions was derived: r = [p(CH3OH)p(H2O)]0.5[p(H2)]-1.3.

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Raman Spectroscopy Investigation of Graphene Oxide Reduction by Laser Scribing

C – Journal of Carbon Research ◽

10.3390/c7020048 ◽

2021 ◽

Vol 7 (2) ◽

pp. 48

Author(s):

Vittorio Scardaci ◽

Giuseppe Compagnini

Keyword(s):

Raman Spectroscopy ◽

Graphene Oxide ◽

Reduce Graphene Oxide ◽

Oxide Reduction ◽

Material Parameters ◽

Laser Scribing ◽

Wide Range ◽

Scan Speed ◽

Laser Reduction

Laser scribing has been proposed as a fast and easy tool to reduce graphene oxide (GO) for a wide range of applications. Here, we investigate laser reduction of GO under a range of processing and material parameters, such as laser scan speed, number of laser passes, and material coverage. We use Raman spectroscopy for the characterization of the obtained materials. We demonstrate that laser scan speed is the most influential parameter, as a slower scan speed yields poor GO reduction. The number of laser passes is influential where the material coverage is higher, producing a significant improvement of GO reduction on a second pass. Material coverage is the least influential parameter, as it affects GO reduction only under restricted conditions.

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Impact of Graphene Oxide on Zero Shear Viscosity, Fatigue Life and Low-Temperature Properties of Asphalt Binder

Materials ◽

10.3390/ma14113073 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3073

Author(s):

Abbas Mukhtar Adnan ◽

Chaofeng Lü ◽

Xue Luo ◽

Jinchang Wang

Keyword(s):

Graphene Oxide ◽

Fatigue Life ◽

Low Temperature ◽

Shear Viscosity ◽

Storage Stability ◽

Asphalt Binder ◽

Asphalt Binders ◽

Test Results ◽

Zero Shear Viscosity ◽

Modified Asphalt

This study has investigated the impact of graphene oxide (GO) in enhancing the performance properties of an asphalt binder. The control asphalt binder (60/70 PEN) was blended with GO in contents of 0%, 0.5%, 1%, 1.5%, 2%, and 2.5%. The permanent deformation behavior of the modified asphalt binders was evaluated based on the zero shear viscosity (ZSV) parameter through a steady shear test approach. Superpave fatigue test and the linear amplitude sweep (LAS) method were used to evaluate the fatigue behavior of the binders. A bending beam rheometer (BBR) test was conducted to evaluate the low-temperature cracking behavior. Furthermore, the storage stability of the binders was investigated using a separation test. The results of the ZSV test showed that GO considerably enhanced the steady shear viscosity and ZSV value, showing a significant contribution of the GO to the deformation resistance; moreover, GO modification changed the asphalt binder’s behavior from Newtonian to shear-thinning flow. A notable improvement in fatigue life was observed with the addition of GO to the binder based on the LAS test results and Superpave fatigue parameter. The BBR test results revealed that compared to the control asphalt, the GO-modified binders showed lower creep stiffness (S) and higher creep rate (m-value), indicating increased cracking resistance at low temperatures. Finally, the GO-modified asphalt binders exhibited good storage stability under high temperatures.

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Kinetics of low-temperature chlorination of vanadium pentoxide by carbon tetrachloride vapor

Metallurgical and Materials Transactions B ◽

10.1007/s11663-005-0020-5 ◽

2005 ◽

Vol 36 (2) ◽

pp. 195-199 ◽

Cited By ~ 4

Author(s):

P. K. Jena ◽

E. A. Brocchi ◽

J. González

Keyword(s):

Carbon Tetrachloride ◽

Low Temperature ◽

Vanadium Pentoxide ◽

Kinetics Of

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Role of Surface Reconstruction and External Ion Beam in the Growth Kinetics of III-V Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-94-83 ◽

1987 ◽

Vol 94 ◽

Cited By ~ 10

Author(s):

S. B. Ogale ◽

M. Thomsen ◽

A. Madhukar

Keyword(s):

Molecular Beam Epitaxy ◽

Low Temperature ◽

Surface Reconstruction ◽

Molecular Beam ◽

Ion Beam ◽

Growth Front ◽

Kinetic Rates ◽

Kinetics Of ◽

Low Temperature Epitaxy

ABSTRACTComputer simulations of III-V molecular beam epitaxy (MBE) show that surface reconstruction induced modulation of kinetic rates could give rise to ordering in alloys. Results are also presented for the possible influence of an external ion beam in achieving low temperature epitaxy as well as smoother growth front under usual conditions.

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