Effect of magnesium on the aluminothermic reduction rate of zinc oxide obtained from spent alkaline battery anodes for the preparation of Al–Zn–Mg alloys

2016 ◽  
Vol 23 (4) ◽  
pp. 458-465 ◽  
Author(s):  
Rocio Ochoa ◽  
Alfredo Flores ◽  
Jesus Torres
Keyword(s):  
Zinc Oxide ◽  
Reduction Rate ◽  
Mg Alloys ◽  
Aluminothermic Reduction ◽  
Alkaline Battery

scholarly journals Influence of Different Carbon Content on Reduction of Zinc Oxide via Metal Bath

2022 ◽  
Vol 12 (2) ◽  
pp. 664
Author(s):  
Michael Auer ◽  
Christoph Wölfler ◽  
Jürgen Antrekowitsch
Keyword(s):  
Zinc Oxide ◽  
Carbon Content ◽  
Reduction Rate ◽  
Iron Alloy ◽  
Reaction Rates ◽  
Processing Temperature ◽  
Metal Bath ◽  
Waelz Process ◽  
Metal Recycling ◽  
Iron Bath

Electric arc furnace dust (EAFD) is an important secondary resource for the zinc industry. The most common process for its recycling is the pyro-metallurgical treatment in the Waelz process. However, this process focuses on the recycling of the zinc, whereas the recovery of other metals from the EAFD—such as iron and other alloying elements—is neglected. An up-to-date version of reprocessing can involve multi-metal recycling by means of a metal bath containing carbon. The use of a liquid iron alloy requires a higher processing temperature, which enables the reduction and melting of iron oxides as well as other compounds occurring in the dust. Furthermore, the Zn yield is higher and the reduction kinetics are faster than in the Waelz process. This paper is only focused on the zinc reduction in such a metal bath. In order to determine the influence of the carbon content in the molten metal on the reduction rate, experiments were carried out on the reduction behavior of zinc oxide using a synthetic slag. This slag, with a basicity B2 = 1, was applied to an iron bath with varying carbon contents. (0.85%, 2.16%, 2.89%, and 4.15%) The decrease in the zinc oxide concentration was monitored, along with the reaction rates calculated from these data. It was found that the reaction rate increases with rising carbon content in the melt.

Effect of Ag/ZnO-Graphitic Carbon Nitride on Antimicrobial Activity under Visible Light

2020 ◽  
Vol 858 ◽  
pp. 116-121
Author(s):  
Sirirat Rodmuang ◽  
Raweewan Plairaharn ◽  
Kanokwan Teingtum ◽  
Suntree Sangjan ◽  
Orawan Chunhachart
Keyword(s):  
Antimicrobial Activity ◽  
Zinc Oxide ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Carbon Nitride ◽  
Dye Degradation ◽  
Reduction Rate ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Precipitation Method

Zinc oxide-graphitic carbon nitride (ZnO/g-C3N4) composites were synthesized by precipitation method in order to improve photocatalytic activity under visible light. To enhance antimicrobial activity, silver was added into zinc oxide-graphitic carbon nitride (Ag/ZnO/g-C3N4). Ultrastructures of the composite were analyzed by X-ray diffractometry (XRD) and transmission electron microscopy (TEM). Photocatalytic activity of the composites was carried out by degradation of methylene blue solution as a function of contact time. The results revealed that ZnO/g-C3N4 was capable of dye degradation at 96.65%. Addition of Ag into ZnO/g-C3N4 resulted in increase of dye reduction rate. For antibacterial test, Ag/ZnO/g-C3N4 exhibited bactericidal activity against Pseudomonas aeruginosa and Bacillus cereus. For antifungal test, Ag/ZnO/g-C3N4 showed resistance to Aspergillusniger for 7 days. Ag/ZnO-g-C3N4 composite exhibited better photocatalytic and antimicrobial activities compare to ZnO and g-C3N4. These results indicate that precipitation method is a cheap, rapid and efficient method that can be used to synthesize Ag/ZnO-g-C3N4 composites. For further studies, applications of this Ag/ZnO-g-C3N4 composites in microbiological and agricultural fields will be carried out.

Dependence of zinc oxide reduction rate on the CO concentration in CO/CO2 mixtures

1996 ◽  
Vol 278 ◽  
pp. 129-134 ◽  
Author(s):  
G. González ◽  
Z.Szczygiel Jordens ◽  
S. Escobedo
Keyword(s):  
Zinc Oxide ◽  
Reduction Rate ◽  
Oxide Reduction ◽  
Co Concentration

Extraction and identification of fillers and pigments from pyrolyzed rubber and tire samples

1996 ◽  
Vol 54 ◽  
pp. 174-175
Author(s):  
P. Sadhukhan ◽  
J. B. Zimmerman
Keyword(s):  
Zinc Oxide ◽  
Electron Microscope ◽  
Carbon Black ◽  
Natural Rubber ◽  
Transmission Electron Microscope ◽  
Rolling Resistance ◽  
Synthetic Polymers ◽  
Nitrogen Atmosphere ◽  
Transmission Electron ◽  
Curing Agents

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.

Electron-Probe Quantitative Energy-Dispersive Analysis of Trace Magnesium Concentrations in Ag-Mg Alloys

1996 ◽  
Vol 54 ◽  
pp. 510-511
Author(s):  
R. B. Marinenko
Keyword(s):  
Electron Probe ◽  
Energy Dispersive Spectrometry ◽  
Mg Alloys ◽  
Energy Dispersive ◽  
Energy Dispersive Analysis ◽  
High Tc ◽  
Alloy Wire ◽  
High Tc Superconductor ◽  
Eds Analysis ◽  
Superior Mechanical Properties

Internally oxidized Ag-Mg alloys are used as sheaths for high Tc superconductor wires because of their superior mechanical properties. The preparation and characteristics of these materials have been reported. Performance of the sheaths depends on the concentration of the magnesium which generally is less than 0.5 wt. percent. The purpose of this work was to determine whether electron probe microanalysis using energy dispersive spectrometry (EDS) could be used to quantitate three different Ag-Mg alloys. Quantitative EDS analysis can be difficult because the AgL escape peak occurs at the same energy (1.25 keV) as the Mg Kα peak. An EDS spectrum of a Ag-Mg alloy wire is compared to a pure Ag spectrum in Fig. 1.

Analysis of Sputtered Zinc Oxide Films

1980 ◽  
Vol 38 ◽  
pp. 416-417
Author(s):  
T. A. Emma ◽  
M. P. Singh
Keyword(s):  
Electron Microscopy ◽  
Zinc Oxide ◽  
Piezoelectric Materials ◽  
Oxide Films ◽  
Optical Quality ◽  
Zno Films ◽  
Rf Power ◽  
X Ray Diffraction ◽  
Sputtered Films ◽  
Zinc Oxide Films

Optical quality zinc oxide films have been characterized using reflection electron diffraction (RED), replication electron microscopy (REM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Significant microstructural differences were observed between rf sputtered films and planar magnetron rf sputtered films. Piezoelectric materials have been attractive for applications to integrated optics since they provide an active medium for signal processing. Among the desirable physical characteristics of sputtered ZnO films used for this and related applications are a highly preferred crystallographic texture and relatively smooth surfaces. It has been found that these characteristics are very sensitive to the type and condition of the substrate and to the several sputtering parameters: target, rf power, gas composition and substrate temperature.

Effect of CaO Addition on the High-Temperature Oxidation of Mg Alloys

2016 ◽  
Vol 54 (6) ◽  
pp. 390-399 ◽  
Author(s):  
Dong Bok Lee ◽  
Shae Kwang Kim ◽  
Soon Yong Park
Keyword(s):  
High Temperature ◽  
High Temperature Oxidation ◽  
Mg Alloys ◽  
Temperature Oxidation

Investigation of the natural ventilation of wind catchers with different geometries in arid region houses

2020 ◽  
Vol 14 (3) ◽  
pp. 7109-7124
Author(s):  
Nasreddine Sakhri ◽  
Younes Menni ◽  
Houari Ameur ◽  
Ali J. Chamkha ◽  
Noureddine Kaid ◽  
...  
Keyword(s):  
Arid Region ◽  
Natural Ventilation ◽  
Reduction Rate ◽  
Internal Flow ◽  
Climatic Conditions ◽  
Maximum Pressure ◽  
Ventilation Technique ◽  
Window Position ◽  
The One ◽  
Flow Velocities

The wind catcher or wind tower is a natural ventilation technique that has been employed in the Middle East region and still until nowadays. The present paper aims to study the effect of the one-sided position of a wind catcher device against the ventilated space or building geometry and its natural ventilation performance. Four models based on the traditional design of a one-sided wind catcher are studied and compared. The study is achieved under the climatic conditions of the South-west of Algeria (arid region). The obtained results showed that the front and Takhtabush’s models were able to create the maximum pressure difference (ΔP) between the windward and leeward of the tower-house system. Internal airflow velocities increased with the increase of wind speed in all studied models. For example, at Vwind = 2 m/s, the internal flow velocities were 1.7, 1.8, 1.3, and 2.5 m/s for model 1, 2, 3, and 4, respectively. However, at Vwind = 6 m/s, the internal flow velocities were 5.6, 5.5, 2.5, and 7 m/s for model 1, 2, 3, and 4, respectively. The higher internal airflow velocities are given by Takhtabush, traditional, front and middle tower models, respectively, with a reduction rate between the tower outlet and occupied space by 72, 42, 36, and 33% for the middle tower, Takhtabush, traditional tower, and the front model tower, respectively. This reduction is due to the due to internal flow resistance. The third part of the study investigates the effect of window (exist opening) position on the opposite wall. The upper, middle and lower window positions are studied and compared. The air stagnation or recirculation zone inside the ventilated space reduced from 55% with the lower window to 46% for the middle window and reached 35% for the upper window position. The Front and Takhtabush models for the one-sided wind catcher with an upper window position are highly recommended for the wind-driven natural ventilation in residential houses that are located in arid regions.

CORTICOSTEROID-UMSATZ UND CORTICOSTEROID-PRODUKTION BEI RATTEN UNTER DER BEHANDLUNG MIT ANABOLEN STEROIDEN

1965 ◽  
Vol 48 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Herbert Schriefers ◽  
Gerlinde Scharlau ◽  
Franzis Pohl
Keyword(s):  
Production Rate ◽  
Adult Female ◽  
Anabolic Steroids ◽  
Reduction Rate ◽  
Female Rats ◽  
Adrenal Weight ◽  
Hydrogenase Activity ◽  
Anabolic Effect ◽  
Liver Slices

ABSTRACT After the administration of anabolic steroids to adult female rats in daily doses of 1 mg per animal for 14 days, the following parameters were investigated: the rate of the Δ4-5α-hydrogenase-catalyzed cortisone reduction in liver slices and microsomal fractions, the adrenal weight and the in vitro corticosterone production rate. Among the steroids tested, only 17α-methyl-testosterone and 17α-ethyl-19-nor-testosterone were effective in lowering significantly cortisone reduction rate by liver slices with concomitant decreases in microsomal Δ4-5α-hydrogenase-activity. Testosterone, 19-nor-testosterone, 17α-ethinyl-19-nor-testosterone, 17α-methyl-17β-hydroxy-androsta-1,4-dien-3-one and 1-methyl-17β-hydroxy-androst-1-en-3-one were ineffective or only slightly effective. Adrenal weight and absolute corticosterone production rate (μg/60 min per animal) were decreased after treatment with 17α-methyl-testosterone, 17α-ethyl-19-nor-testosterone and 1-methyl-17β-hydroxy-androst-1-en-3-one. Corticosterone production was decreased with 17α-ethinyl-19-nor-testosterone in spite of an unchanged adrenal weight. The relative corticosterone production rate (μg/60 min · 100 mg adrenal) was in any cases unaffected. According to these results there exists – with the exception of 17α-ethinyl-19-nor-testosterone – a strict parallelism between corticosteroid turnover and corticosterone production rate: unchanged turnover is correlated with unchanged corticosterone production rate, while a decreased turnover is correlated with decreased adrenal activity. The protein-anabolic effect of certain anabolic steroids may be partly due to an anti-catabolic action of these compounds resulting from a decreased corticosteroid inactivation and production rate. Possible mechanisms by which anabolic steroids may affect corticosteroid-balance are discussed.

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