Study of photocatalytic properties of clay intercalated semiconductor composite material of guanidinium tetrachloroferrate for oxidative degradation of model dye in sunlight

Author(s):  
Kabita Boruah ◽  
Debanga Bhusan Bora ◽  
Susmita Saikia ◽  
Ruli Borah
2021 ◽  
Vol 316 ◽  
pp. 56-61
Author(s):  
N.P. Shabelskaya ◽  
M.A. Egorova ◽  
E.V. Vasilieva

The present research is devoted to the formation process of a nanoscale composite material with the composition of CoFe2O4/α-Fe2O3. The synthesized material has been studied by the following methods: x-ray phase analysis and scanning electron microscopy. The produced sample is analyzed to be a CoFe2O4 cabic spinel with a unit cell parameters of a = 0.8394 nm and α-Fe2O3. The average crystallite size of the resulting samples, determined by the Debye-Scherrer equation, is 4.8 nm for the cobalt (II) ferrite and 7.9 nm for α-Fe2O3. Reaction rate increase is determined by the incease in hydrogen peroxide amount in the solution. The synthesized composite material is found to exhibit increased catalytic activity in the oxidative degradation reaction of organic dye by hydrogen peroxide. The catalytic activity is established to be particularly high, when the process is occurring in acidic medium. The obtained samples have a highly developed surface and may be of interest as catalysts, adsorbents.


Author(s):  
E. Sukedai ◽  
H. Mabuchi ◽  
H. Hashimoto ◽  
Y. Nakayama

In order to improve the mechanical properties of an intermetal1ic compound TiAl, a composite material of TiAl involving a second phase Ti2AIN was prepared by a new combustion reaction method. It is found that Ti2AIN (hexagonal structure) is a rod shape as shown in Fig.1 and its side surface is almost parallel to the basal plane, and this composite material has distinguished strength at elevated temperature and considerable toughness at room temperature comparing with TiAl single phase material. Since the property of the interface of composite materials has strong influences to their mechanical properties, the structure of the interface of intermetallic compound and nitride on the areas corresponding to 2, 3 and 4 as shown in Fig.1 was investigated using high resolution electron microscopy and image processing.


Author(s):  
O. Popoola ◽  
A.H. Heuer ◽  
P. Pirouz

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.


Nanoscale ◽  
2020 ◽  
Vol 12 (30) ◽  
pp. 16136-16142
Author(s):  
Xuan Wang ◽  
Ming-Jie Dong ◽  
Chuan-De Wu

An effective strategy to incorporate accessible metalloporphyrin photoactive sites into 2D COFs by establishing a 3D local connection for highly efficient photocatalysis was developed.


2019 ◽  
pp. 9-13
Author(s):  
V.Ya. Mendeleyev ◽  
V.A. Petrov ◽  
A.V. Yashin ◽  
A.I. Vangonen ◽  
O.K. Taganov

Determining the surface temperature of materials with unknown emissivity is studied. A method for determining the surface temperature using a standard sample of average spectral normal emissivity in the wavelength range of 1,65–1,80 μm and an industrially produced Metis M322 pyrometer operating in the same wavelength range. The surface temperature of studied samples of the composite material and platinum was determined experimentally from the temperature of a standard sample located on the studied surfaces. The relative error in determining the surface temperature of the studied materials, introduced by the proposed method, was calculated taking into account the temperatures of the platinum and the composite material, determined from the temperature of the standard sample located on the studied surfaces, and from the temperature of the studied surfaces in the absence of the standard sample. The relative errors thus obtained did not exceed 1,7 % for the composite material and 0,5% for the platinum at surface temperatures of about 973 K. It was also found that: the inaccuracy of a priori data on the emissivity of the standard sample in the range (–0,01; 0,01) relative to the average emissivity increases the relative error in determining the temperature of the composite material by 0,68 %, and the installation of a standard sample on the studied materials leads to temperature changes on the periphery of the surface not exceeding 0,47 % for composite material and 0,05 % for platinum.


2020 ◽  
Vol 1 (12) ◽  
pp. 36-39
Author(s):  
L. V. Iyashvili ◽  
Yu. A. Vinnichenko ◽  
A. V. Vinnichenko

The purpose of the study is a quantitative assessment of the yield of dentinal fluid on the surface of the treated dentin of the tooth when restoring its structure with a composite filling material. To achieve this goal, digital images of the coronal parts of the teeth having formed carious cavities were used; virtual models of hard tissues of teeth recreated using specialized computer programs; A computer program that provides the ability to accurately determine the area of the treated dentin tooth. The results made it possible to draw the following conclusions: with an increase in the depth of the carious cavity, the amount of dentin fluid that can stand out on its surface (1–2 mm from the tooth cavity) sharply increases; with an increase in the area of the formed carious cavity (more than 30 mm2), the risk of release of a critical mass of dentinal fluid (more than 0.4 mg), which can adversely affect the strength of the adhesive interaction between the composite material and the hard tissues of the tooth, increases significantly; the same dynamics is observed with increasing time, at which there is the possibility of free exit of dentinal fluid to the surface of the cavity prepared for filling (more than 45 seconds).


Sign in / Sign up

Export Citation Format

Share Document