Sintering Studies and Microstructural Evolution of Fe-MoS2 Mixtures

2014 ◽  
Vol 802 ◽  
pp. 415-420 ◽  
Author(s):  
Kaline Pagnan Furlan ◽  
Julia Zimmermann de Assunção ◽  
Gustavo Paz ◽  
Cristiano Binder ◽  
Aloisio Nelmo Klein
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Molybdenum Disulfide ◽  
Microstructural Evolution ◽  
Solid Lubricant ◽  
Particle Sizes ◽  
Iron Sulfides ◽  
Iron And Steel ◽  
The World

The development of dry self-lubricating materials is directly linked to the rising requirements of performance. Iron and steel are the most used metals around the world and molybdenum disulfide (MoS2) one of the most used solid lubricant. Therefore it is expected that one might try to develop self-lubricating steels containing MoS2, however MoS2 reacts with steel matrices during sintering. This work has focused on the study of these reactions; temperatures at which this occurs; the influence of particle sizes and MoS2 content and also MoS2 influence during processing and in the parts properties. The results showed that the reaction occurs at lower temperatures than the predicted and the products are iron-molybdenum and iron sulfides. The sintering studies revealed that MoS2 enhances sintering and the particle size and MoS2 content directly influenced the morphology and chemical composition of the resulting phases.

scholarly journals Influence of the Collection Season on Production, Size, and Chemical Composition of Bee Pollen Produced by Apis Mellifera L.

2014 ◽  
Vol 58 (2) ◽  
pp. 5-10 ◽  
Author(s):  
Adriana F. Negrão ◽  
Lidia M. R. C. Barreto ◽  
Ricardo O. Orsi
Keyword(s):  
Particle Size ◽  
Apis Mellifera ◽  
Chemical Composition ◽  
Protein Content ◽  
Nutritional Quality ◽  
Particle Sizes ◽  
Bee Pollen ◽  
Pollen Loads ◽  
Food Scarcity ◽  
Collection Period

Abstract The aim of our study was to investigate how the collection period affects and influences the production, chemical composition, and size of bee pollen loads (0.5, 1.0, 2.0, greater than 2.0 mm). The results showed there was a predominance of pollen loads with a diameter greater than 2.0 mm in all the production seasons. For all the seasons, there were no differences in protein content between the particle sizes. But when comparing 0.5 mm during the different periods, there were significant differences; the highest value was found during the winter (24.39 ± 3.7%). As far as lipids and crude fiber are concerned, we obtained differences between the same granulometry sizes for the spring and summer seasons. As for ashes, the results showed differences between different particle sizes for the summer and autumn seasons. Our results have shown that regardless of pollen particle size, its quality was not altered, suggesting that smaller loads can be commercially used by containing nutritional quality or else be used by beekeepers as a supplement during periods of food scarcity.

scholarly journals The influence of fraction size on the chemical composition of winter wheat flour

2010 ◽  
pp. 123-126
Author(s):  
Zsuzsanna Tarján ◽  
Ágnes P. Barancsi ◽  
Zoltán Mezei
Keyword(s):  
Chemical Composition ◽  
Everyday Life ◽  
Wheat Flour ◽  
Particle Sizes ◽  
The Everyday ◽  
The World ◽  
Fraction Size ◽  
Pattern Production ◽  
The Impact

Wheat is one of the most important cereals in the world and the bread made of its flour belongs to the everyday life of human  mankind.The Hungarian standard relating to the laboratory production of wheat flour (MSZ 6367/9-1989) does not mention the type of laboratory mill used for milling, and it only builds up some general criteria, such as: the laboratory mill should be provided  with four differently nicked barrels, a sieve with appropriate hole sizes, and also with the separated collections of the pilot flour and the bran. Our study was started at this point and the answers for the following questions were aimed to be found: do the flour patterns studied and produced with different sieving techniques, widely used in laboratory mills of the same wheat pattern show any alterations after the impact of the formula production as regards chemical constitutions. Various flours of the wheat pattern sieved with different particle sizes were studied in this experiment. In producing this pattern we used FQC109 type of mill. There were 5 different corn sizes of 250-200; 200-160; 160-125; 125-100; <100 μms used in the partition of the fractions. The results this research confirm that the quality of wheat flour can be modified by different methods of pattern production.

Basic Properties of Iron and Steel Making Dust

2014 ◽  
Vol 937 ◽  
pp. 187-190
Author(s):  
Xue Bing Li ◽  
Wei Wang ◽  
Dong Hai Zhang ◽  
Li Xiong
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Iron Content ◽  
Paper Analysis ◽  
Raw Material ◽  
High Iron Content ◽  
Iron And Steel ◽  
Steel Making

A large amount of dust can be produced in iron and steel making process. This paper analysis the chemical composition, particle size distribution and microscopic characteristics of those iron and steel making dust. Some dust with high iron content, some dust with much CaO and some dust with carbon, those indicate that the iron and steel making dust can be used as iron making raw material. But the size of the iron and steel making dust is very small, which will make it harder to deal with those dust.

scholarly journals Study the Effect of Particle Sizes and Concentration on the Rheological Properties of Iraqi Bentonite for Using as Drilling Fluids

2020 ◽  
Vol 26 (3) ◽  
pp. 65-76
Author(s):  
Ahmed Sattar Ibrahim ◽  
Mayssaa Ali Al-bidry
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Particle Size Distribution ◽  
Rheological Properties ◽  
Size Distribution ◽  
Mineral Composition ◽  
Drilling Fluid ◽  
Drilling Fluids ◽  
Particle Sizes ◽  
Effect Of Particle Size

The aim of this study is to identify the effect of particle size and to increase the concentration of Iraqi bentonite on rheological properties in order to evaluate its performance and to know if it can be used as drilling fluid without additives or not. In this study, Iraqi bentonite was carried out by mineral composition (XRD), chemical composition (XRF) and Particle size distribution (PSD), and its rheological properties were measured at different particle size and concentration. The results showed that when the particle size of Iraqi bentonite decreased, and the rheological properties were increased with increased concentration of Iraqi bentonite. Also, Iraqi bentonite was unable to use as drilling fluid without certain additives.

Behaviours of Zinc and Lead in Blast Furnace of Baotou Iron and Steel Group Co.

2011 ◽  
Vol 194-196 ◽  
pp. 306-309 ◽  
Author(s):  
Fang Zhang ◽  
Sheng Li An ◽  
Guo Ping Luo ◽  
Shi Zhong Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Particle Size ◽  
Blast Furnace ◽  
Particle Sizes ◽  
Iron And Steel ◽  
X Ray ◽  
Lead And Zinc ◽  
Particle Size Analyzer ◽  
Scanning Electron

The balance calculation of zinc and lead of No.1 BF of Baotou Iron and Steel Group Co. was performed in this research. The particle sizes of BF dusts were measured by LS230 laser particle size analyzer. The micrology of sinter and dusts were investigated with scanning electron microscopy (SEM, Hitachi S-3000) coupled with an energy-dispersive X-ray analysis (EDX). The results show that the general burdens of zinc and lead in No. 1 mainly came from sinter and pellet. The burdens of zinc and lead in No.1 BF were 645.45g/t and 370.33 g/t respectively, which were too much to need take some measures. Among the gas ash, the particle size of baghouse dust was minimal, but the contents of lead and zinc were highest. So the BF baghouse dust isn’t appropriate to recover as the sintering materials. The speciation of lead is PbO, PbCl3 and metallic Pb, but zinc never presents as metal in BF dusts.

Surface energy of cellulosic materials: The effect of particle morphology, particle size, and hydroxyl number

TAPPI Journal ◽  
2015 ◽  
Vol 14 (9) ◽  
pp. 565-576 ◽  
Author(s):  
YUCHENG PENG ◽  
DOUGLAS J. GARDNER
Keyword(s):  
Particle Size ◽  
Surface Energy ◽  
Particle Morphology ◽  
Nanofibrillated Cellulose ◽  
Particle Sizes ◽  
Hydroxyl Number ◽  
Small Individual ◽  
Dispersion Component ◽  
Commercial Applications ◽  
Lower Temperature

Understanding the surface properties of cellulose materials is important for proper commercial applications. The effect of particle size, particle morphology, and hydroxyl number on the surface energy of three microcrystalline cellulose (MCC) preparations and one nanofibrillated cellulose (NFC) preparation were investigated using inverse gas chromatography at column temperatures ranging from 30ºC to 60ºC. The mean particle sizes for the three MCC samples and the NFC sample were 120.1, 62.3, 13.9, and 9.3 μm. The corresponding dispersion components of surface energy at 30°C were 55.7 ± 0.1, 59.7 ± 1.3, 71.7 ± 1.0, and 57.4 ± 0.3 mJ/m2. MCC samples are agglomerates of small individual cellulose particles. The different particle sizes and morphologies of the three MCC samples resulted in various hydroxyl numbers, which in turn affected their dispersion component of surface energy. Cellulose samples exhibiting a higher hydroxyl number have a higher dispersion component of surface energy. The dispersion component of surface energy of all the cellulose samples decreased linearly with increasing temperature. MCC samples with larger agglomerates had a lower temperature coefficient of dispersion component of surface energy.

scholarly journals Effect of particle size on phytochemical composition and antioxidant properties of Sargassum cristaefolium ethanol extract

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. S. Prasedya ◽  
A. Frediansyah ◽  
N. W. R. Martyasari ◽  
B. K. Ilhami ◽  
A. S. Abidin ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Particle Size ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Ethanol Extract ◽  
Total Phenolic ◽  
Particle Sizes ◽  
Epicatechin Gallate ◽  
Particle Size Reduction ◽  
Phytochemical Composition

AbstractSample particle size is an important parameter in the solid–liquid extraction system of natural products for obtaining their bioactive compounds. This study evaluates the effect of sample particle size on the phytochemical composition and antioxidant activity of brown macroalgae Sargassum cristaefolium. The crude ethanol extract was extracted from dried powders of S.cristeafolium with various particle sizes (> 4000 µm, > 250 µm, > 125 µm, > 45 µm, and < 45 µm). The ethanolic extracts of S.cristaefolium were analysed for Total Phenolic Content (TPC), Total Flavonoid Content (TFC), phenolic compound concentration and antioxidant activities. The extract yield and phytochemical composition were more abundant in smaller particle sizes. Furthermore, the TPC (14.19 ± 2.08 mg GAE/g extract to 43.27 ± 2.56 mg GAE/g extract) and TFC (9.6 ± 1.8 mg QE/g extract to 70.27 ± 3.59 mg QE/g extract) values also significantly increased as particle sizes decreased. In addition, phenolic compounds epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), and Epigallocatechin gallate (EGCG) concentration were frequently increased in samples of smaller particle sizes based on two-way ANOVA and Tukey’s multiple comparison analysis. These results correlate with the significantly stronger antioxidant activity in samples with smaller particle sizes. The smallest particle size (< 45 µm) demonstrated the strongest antioxidant activity based on DPPH, ABTS, hydroxyl assay and FRAP. In addition, ramp function graph evaluates the desired particle size for maximum phytochemical composition and antioxidant activity is 44 µm. In conclusion, current results show the importance of particle size reduction of macroalgae samples to increase the effectivity of its biological activity.

scholarly journals Experimental Analysis of the Mechanical Properties and Resistivity of Tectonic Coal Samples with Different Particle Sizes

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2303
Author(s):  
Congyu Zhong ◽  
Liwen Cao ◽  
Jishi Geng ◽  
Zhihao Jiang ◽  
Shuai Zhang
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Uniaxial Compressive Strength ◽  
Coalbed Methane ◽  
Coal Sample ◽  
Fine Particles ◽  
Particle Sizes ◽  
Tectonic Coal

Because of its weak cementation and abundant pores and cracks, it is difficult to obtain suitable samples of tectonic coal to test its mechanical properties. Therefore, the research and development of coalbed methane drilling and mining technology are restricted. In this study, tectonic coal samples are remodeled with different particle sizes to test the mechanical parameters and loading resistivity. The research results show that the particle size and gradation of tectonic coal significantly impact its uniaxial compressive strength and elastic modulus and affect changes in resistivity. As the converted particle size increases, the uniaxial compressive strength and elastic modulus decrease first and then tend to remain unchanged. The strength of the single-particle gradation coal sample decreases from 0.867 to 0.433 MPa and the elastic modulus decreases from 59.28 to 41.63 MPa with increasing particle size. The change in resistivity of the coal sample increases with increasing particle size, and the degree of resistivity variation decreases during the coal sample failure stage. In composite-particle gradation, the proportion of fine particles in the tectonic coal sample increases from 33% to 80%. Its strength and elastic modulus increase from 0.996 to 1.31 MPa and 83.96 to 125.4 MPa, respectively, and the resistivity change degree decreases. The proportion of medium particles or coarse particles increases, and the sample strength, elastic modulus, and resistivity changes all decrease.

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