Modification of Hydrogen Zeolite with CeO2 and its Catalysis Application for Preparing Aspirin

2014 ◽  
Vol 809-810 ◽  
pp. 884-889
Author(s):  
Zhen Tan ◽  
Hui Ying Chen ◽  
Bi Hao Lan ◽  
Xiang Wen Tong ◽  
Xiao Mei Ba
Keyword(s):  
Heat Treatment ◽  
Calcination Temperature ◽  
Catalytic Efficiency ◽  
Optimal Conditions ◽  
Calcination Time ◽  
Zeolite Framework ◽  
High Efficient ◽  
Zeolite Particle ◽  
Before And After ◽  
Impregnation Temperature

Hydrogen zeolite was modified with CeO2 by impregnation - filtration - heat treatment. Hydrogen-zeolite samples before and after modification were characterized by XRD and SEM. The catalytic efficiency of modified hydrogen-zeolite was investigated. Such modification conditions were explored: as the CeO2 percentage, calcination temperature, calcination time, impregnation temperature. The results show that the optimal CeO2 percentage is 0.5%, calcination temperature is 600°C, calcination time is 2h, impregnation temperature is 75°C. The aspirin yield reaches 78.3% under the optimal conditions, compared with that (64.8%) catalyzed by sulfuric acid and that (70.4%) catalyzed by unmodified zeolite. XRD, SEM characterizations show that Ce ions can be doped into the zeolite framework. And the modification makes the zeolite particle size become smaller, which is reduced to 50.5nm from 56.76nm. A high efficient and eco-enviromently catalyst was got by modification.

scholarly journals Effect of Al 6061 Alloy Compositions on Mechanical Properties of the Automotive Steering Knuckle Made by Novel Casting Process

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 857 ◽  
Author(s):  
Gyu Jeon ◽  
Ki Kim ◽  
Jung-Hwa Moon ◽  
Chul Lee ◽  
Whi-Jun Kim ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Mechanical Strength ◽  
Casting Process ◽  
Optimal Conditions ◽  
Al 6061 ◽  
Minor Elements ◽  
Commercial Grade ◽  
Before And After ◽  
Elongation Percentage

This study demonstrates the feasibility of a novel casting process called tailored additive casting (TAC). The TAC process involves injecting the melt several times to fabricate a single component, with a few seconds of holding between successive injections. Using TAC, we can successfully produce commercial-grade automotive steering knuckles with a tensile strength of 383 ± 3 MPa and an elongation percentage of 10.7 ± 1.1%, from Al 6061 alloys. To produce steering knuckles with sufficient mechanical strength, the composition of an Al 6061 alloy is optimized with the addition of Zr, Zn, and Cu as minor elements. These minor elements influence the thermal properties of the melt and alloy, such as their thermal stress, strain rate, shrinkage volume, and porosity. Optimal conditions for heat treatment before and after forging further improve the mechanical strength of the steering knuckles produced by TAC followed by forging.

The Precipitation of Si in AlCuSi Thin Films

1973 ◽  
Vol 31 ◽  
pp. 34-35 ◽  
Author(s):  
R. M. Anderson
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Heat Treatment ◽  
Solid Solution ◽  
Integrated Circuit ◽  
Copper Film ◽  
Solution Concentration ◽  
X Ray ◽  
Silicon Thin Films ◽  
Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

Study of fine structure of cold-deformed steel 20 before and after prerecrystallization heat treatment

2015 ◽  
Vol 0 (1) ◽  
Author(s):  
Oleksandr M. Dubovyi ◽  
Oleksandr V. Chechel ◽  
Oleksandr O. Zhdanov
Keyword(s):  
Heat Treatment ◽  
Fine Structure ◽  
Before And After ◽  
Steel 20

Influence of the Zinc Sublayer Method Production and Heat Treatment on the Microhardness of the Composite Ni-Al2O3 Coating Deposited on the 5754 Aluminium Alloy

2014 ◽  
Vol 59 (1) ◽  
pp. 355-358
Author(s):  
M. Karaś ◽  
M. Nowak ◽  
M. Opyrchał ◽  
M. Bigaj ◽  
A. Najder
Keyword(s):  
Heat Treatment ◽  
Aluminium Alloy ◽  
Thermal Shock ◽  
Nickel Coating ◽  
Nickel Sulphate ◽  
Al2o3 Coating ◽  
Nickel Coatings ◽  
Watts Bath ◽  
Before And After ◽  
Zinc Interlayer

Abstract In this study, the effect of zinc interlayer on the adhesion of nickel coatings reinforced with micrometric Al2O3 particles was examined. Nickel coating was applied by electroplating on EN AW - 5754 aluminium alloy using Watts bath at a concentration of 150 g/l of nickel sulphate with the addition of 50 g/l of Al2O3. The influence of zinc intermediate coating deposited in single, double and triple layers on the adhesion of nickel coating to aluminium substrate was also studied. The adhesion was measured by the thermal shock technique in accordance with PN-EN ISO 2819. The microhardness of nickel coating before and after heat treatment was additionally tested. It was observed that the number of zinc interlayers applied does not significantly affect the adhesion of nickel which is determined by thermal shock. No defect that occurs after the test, such as delamination, blistering or peeling of the coating was registered. Microhardness of the nickel coatings depends on the heat treatment and the amount of zinc in the interlayer. For both single and double zinc interlayer, the microhardness of the nickel coating containing Al2O3 particles increased after heat treatment, but decreased when a triple zinc interlayer was applied.

scholarly journals The Interface Zone of Explosively Welded Titanium/Steel after Short-Term Heat Treatment

2021 ◽  
Author(s):  
Marcin Szmul ◽  
Katarzyna Stan-Glowinska ◽  
Marta Janusz-Skuza ◽  
Agnieszka Bigos ◽  
Andrzej Chudzio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Intermetallic Phase ◽  
Welding Process ◽  
Carbon Diffusion ◽  
Sharp Interface ◽  
High Plasticity ◽  
Interface Zone ◽  
Before And After ◽  
Wavy Interface ◽  
The Waves

AbstractThis work presents a detailed description of a bonding zone of explosively welded Ti/steel clads subjected to stress relief annealing, applied in order to improve the plasticity of the final product. The typical joint formed by the welding process possesses a characteristic wavy interface with melted regions observed mainly at the crest regions of waves. The interface of Ti/steel clads before and after annealing was previously investigated mostly in respect to the melted regions. Here, a sharp interface between the waves was analyzed in detail. The obtained results indicate that the microstructure of a transition zone of that area is different along the width. After the heat treatment at 600 °C for 1.5 hours, titanium carbide (TiC) together with α-Fe phase forms at the interface in local areas of relatively wide interlayer (~ 1 µm), while for most of the sharp interface, a much thinner zone up to about 400 nm, formed by four sublayers containing intermetallic phase and carbides, is present. This confirms that carbon diffusion induced by applied heat treatment significantly influences the final microstructure of the Ti/steel interface zone. Side bending tests confirmed high plasticity of welds after applied heat treatment; however, the microhardness measurements indicated that the strengthening of the steel in the vicinity of the interface had not been removed completely.

Microstructure and Mechanical Properties of Ti-6Al-4V Manufactured by SLM

2015 ◽  
Vol 651-653 ◽  
pp. 677-682 ◽  
Author(s):  
Anatoliy Popovich ◽  
Vadim Sufiiarov ◽  
Evgenii Borisov ◽  
Igor Polozov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Phase Composition ◽  
Mechanical Behavior ◽  
Ductile Fracture ◽  
Elevated Temperatures ◽  
Initial Material ◽  
Laser Melting ◽  
Microstructure And Mechanical Properties ◽  
Before And After

The article presents results of a study of phase composition and microstructure of initial material and samples obtained by selective laser melting of titanium-based alloy, as well as samples after heat treatment. The effect of heat treatment on microstructure and mechanical properties of specimens was shown. It was studied mechanical behavior of manufactured specimens before and after heat treatment at room and elevated temperatures as well. The heat treatment allows obtaining sufficient mechanical properties of material at room and elevated temperatures such as increase in ductility of material. The fractography of samples showed that they feature ductile fracture with brittle elements.

Sedimentary Clays as Geopolymer Precursor

2018 ◽  
Vol 39 ◽  
pp. 97-111
Author(s):  
F. Mostefa ◽  
Nasr Eddine Bouhamou ◽  
H.A. Mesbah ◽  
Salima Aggoun ◽  
D. Mekhatria
Keyword(s):  
Sodium Hydroxide ◽  
Mineralogical Composition ◽  
Cementitious Materials ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Calcination Time ◽  
Calorimetric Analysis ◽  
X Ray ◽  
Before And After ◽  
Mechanical Performances

This work aims to study the feasibility of making a geopolymer cement based on dredged sediments, from the Fergoug dam (Algeria) and to evaluate their construction potential particularly interesting in the field of special cementitious materials. These sediments due to their mineralogical composition as aluminosilicates; are materials that can be used after heat treatment. Sedimentary clays were characterized before and after calcination by X-ray diffraction, ATG / ATD, spectroscopy (FTIR) and XRF analysis. The calcination was carried out on the raw material sieved at 80 μm for a temperature of 750 ° C, for 3.4 and 5 hours. The reactivity of the calcined products was measured using isothermal calorimetric analysis (DSC) on pastes prepared by mixing an alkaline solution of sodium hydroxide (NaOH) 8 M in an amount allowing to have a Na / Al ratio close to 1 (1: 1). Also, cubic mortar samples were prepared with a ratio L / S: 0.8, sealed and cured for 24 hours at 60 ° C and then at room temperature until the day they were submited to mechanical testing. to check the extent of geopolymerization. The results obtained allowed to optimize the calcination time of 5 hours for a better reactivity of these sediments, and a concentration of 8M of sodium hydroxide and more suitable to have the best mechanical performances.

Surface Modification of Nano-Al2O3 with Stearic Acid

2016 ◽  
Vol 703 ◽  
pp. 246-250
Author(s):  
Min Hong Xu ◽  
Jian Li Ma ◽  
Meng Xia Qian ◽  
Li Hua Jiang
Keyword(s):  
Surface Modification ◽  
Stearic Acid ◽  
Influence Factors ◽  
Optimal Conditions ◽  
Modification Effect ◽  
Before And After

Surface modification of nanoAl2O3 with stearic acid by dry method was researched. The structures of nanoAl2O3 before and after modified were characterized by IR. The modification effect on nanoAl2O3 was measured with the activation index. In addition, the influence factors of modifier dosage, modification time and modification temperature were also discussed. The results showed that nanoAl2O3 had been successfully modified with stearic acid. The hydrophily and lipophilicity experiments indicated that modified nanoAl2O3 possessed lipophilicity property and could disperse in xylene. The optimal conditions of modification were as follows: the stearic acid was 7.5 wt%, based on the quality of nanoAl2O3, modification time was 50 min and temperature was 150 ○C.

The Phase Analysis of Panzhihua Vanadic Titanomagnetite Ore before and after Heat Treatment

2013 ◽  
Vol 807-809 ◽  
pp. 2110-2114
Author(s):  
Shu Quan Wan ◽  
De Jun Lan ◽  
Hong Bo Han ◽  
Cai Long Zhou
Keyword(s):  
Heat Treatment ◽  
Phase Analysis ◽  
Room Temperature ◽  
Before And After

The phases of Panzhihua vanadic titanomagnetite ore were studied by using XRF and XRD. XRF results show that the original ore mainly contain the elements, Fe, Ti, Si, Ca, Al, S, Mg, P, Mn, V and etc. XRD results show that the main substances in original ore were Fe3O4 and FeTiO3, and the minor phases cannot be clearly studied by XRD. After heat treatment for 10h at 573K in atmospheric ambient, the phases of the ore have been slightly changed. And after heat treatment for 10h at 1073K in atmospheric ambient, then cooled for 48h to room temperature, the main phases of the ore have almost been changed to Fe2O3 and Fe2TiO5.

Exoelectron emission from unexcited metallic glasses Fe78B13Si9 during heat treatment

1992 ◽  
Vol 7 (6) ◽  
pp. 1396-1399 ◽  
Author(s):  
Yoshihisa Watanabe ◽  
Tadayoshi Kubozoe ◽  
Yoshikazu Nakamura
Keyword(s):  
Heat Treatment ◽  
Metallic Glasses ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Exoelectron Emission ◽  
Radiation Chemical ◽  
Temperature Range ◽  
High Vacuum Condition ◽  
Before And After ◽  
Ultra High Vacuum Condition

Exoelectron emission from the surface of unexcited metallic glasses Fe78B13Si9 during heat treatment has been studied under ultra high vacuum condition. In the first heating cycle, exoelectrons are emitted from the as-cast ribbon in the temperature range from approximately 423 K to 773 K (150 °C to 500 °C), although the surface of the specimen is not excited by ionizing radiation, chemical processes, or mechanical treatments prior to measurements. In the second and subsequent heating cycles, however, there is no anomalous emission observed in the same temperature range. In order to elucidate the mechanism of emission, the surface of the specimen is observed by the atomic force microscope (AFM) before and after measurements. In the AFM image, many crystallites in the amorphous matrix can be found in the surface of the heated specimen. These experimental results show that exoelectrons are emitted in the same temperature range as the early stages of crystallization on the surface of metallic glasses. We hypothesize that the two effects are correlated.

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