STUDI SIFAT MAGNETIK DAN UKURAN PARTIKEL ABU VULKANIK ERUPSI GUNUNG SINABUNG KABUPATEN KARO MENGGUNAKAN PROBE PASCO 2162

This study aims to determine the magnetic properties and particle size of the volcanic ash of Sinabung Mount with experiment method. Magnetic properties studied were magnetic degree, magnetic induction magnetic susceptibility, and mass susceptibility of sample. The samples used were volcanic ash taken from the west part of Sinabung, precisely at Gurukinayan village. The ash samples were taken horizontally on the slopes of the Mountain with the amount of 1.5 Kg each point with the number of 10 points (A to J). Separation of concentrate of ash was done using a Neodymium Iron Boron (NdFeB). The magnetic induction of ash and concentrate was measured using a Pasco 2162 Probe using a solenoid is 3 cm in diameter, 10 cm in length and 2000 coil turns. Magnetic induction without a core was measured as a current function (2,4,6,8,10)A and a distance of 1 to 5 mm. The total magnetic induction of ash and concentrate was measured as a current function and the particle sizes was measured using a Light Microscope. The results showed that the greate magnetic degree value at point B of 7.02% and the lowerst level of magnetism is at point J was 1.07%. The largest particle sizes is at point B and the smallest is at point J with particle size of 0.175-0.90 mm. The highest average magnetic susceptibility value for concentrate at point B is 87.32 x 10-3 and the lowest at point F is 20 x 10-3. Based on the mass susceptibility value of the concentrate obtained the volcanic ash of Mount Sinabung is at interval (46–80.000) x 10-8 m3/kg of mass susceptibility value at each location point which contains Ilmenite particles (FeTiO3).

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Hydrothermal Synthesis of CoFe2O4 Nanoparticles and their Magnetic Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.1358 ◽

2013 ◽

Vol 821-822 ◽

pp. 1358-1361 ◽

Cited By ~ 2

Author(s):

Fan Zhang ◽

Rui Liang Su ◽

Li Zhi Shi ◽

Yang Liu ◽

Yan Na Chen ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Room Temperature ◽

Magnetic Measurements ◽

Spinel Ferrite ◽

Synthesis Method ◽

Ferrite Nanoparticles ◽

Particle Sizes ◽

Naoh Solution ◽

20 Nm

CoFe2O4 (CFO) nanoparticles was synthesized by a simple hydrothermal method using NaOH solution as a mineralizer at 200 °C for 4 h. It was found that CFO particle sizes decreased firstly and then increased with the increasing of NaOH concentration, and had a minumum value about 10-20 nm when selected 4 mol/L NaOH solution, indicating the NaOH concentration played an important role in controlling the particle size of CFO powders. The room temperature magnetic measurements showed that the saturation magnetization value was 48 emu/g, which is less than the bulk value. The synthesis method is possible to be a general approach for the preparation of other spinel ferrite nanoparticles.

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Determination Of Power Loss In Fe-Based Soft Magnetic Composites

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0143 ◽

2015 ◽

Vol 60 (2) ◽

pp. 1411-1415 ◽

Cited By ~ 3

Author(s):

B. Jankowski ◽

D. Kapelski ◽

B. Ślusarek ◽

J. Szczygłowski

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Composite Materials ◽

Particle Size Distribution ◽

Power Loss ◽

Particle Sizes ◽

Soft Magnetic ◽

Magnetic Composites ◽

Soft Magnetic Composites

Abstract The magnetic properties of Fe-based composite materials with different particle sizes were investigated. The results of energy loss density were obtained from measurements of the static (DC) hysteresis cycles ranging from 0,2 to 1,4 T. In turn, the results of power loss density were obtained from measurements of the dynamic (AC) hysteresis cycles ranging from 20 to 400 Hz and at the maximum flux density 0,3; 0,9 and 1,3 T. Two sets of specimens was analyzed in the investigation: the specimens compacted under pressure of 800 MPa and hardened at 500°C and the specimens compacted under different pressure and hardened at 500°C. Specimens of the second set had the same density. The study confirmed the influence of particle size distribution on magnetic properties of Fe-based soft magnetic composites.

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PENENTUAN SIFAT MAGNETIK PASIR DAN DEBU SEPANJANG JALAN KARTAMA KOTA PEKANBARU MENGGUNAKAN MAGNETIC PROBE PASCO PS-2162

Komunikasi Fisika Indonesia ◽

10.31258/jkfi.16.1.12-19 ◽

2019 ◽

Vol 16 (1) ◽

pp. 12

Author(s):

Maria Sonya Nauli Nainggolan ◽

Erwin Erwin ◽

Yanuar Yanuar ◽

Usman Malik

Keyword(s):

Heavy Metals ◽

Magnetic Properties ◽

Magnetic Susceptibility ◽

Magnetic Induction ◽

Magnetic Particles ◽

Magnetic Probe ◽

Horizontal Distance ◽

Sample Number ◽

The Road ◽

Induction Measurement

Topsoil is the recipient of various kinds pollutants, especially heavy metals. Heavy metals have been detected in sand and dust along the highway. Measuring the magnetic properties of road sediment along Kartama road in Pekanbaru City has been done. The magnetic properties measured are magnetic degree, magnetic and mass susceptibility using magnetic induction measurement. The Samples were taken at sixteen locations with the amount of 1 or 2 kg for each point location, the samples were named as samples 16, 7a7e, 8a8e. The magnetic particles of the samples were separated from sand and dust using Iron Sand Separator and later using Neodymium Iron Boron (NdFeB) magnet. The total magnetic induction of the samples and concentrates were measured using Pasco Magnetic Probe PS-2162. In order to measure the magnetic induction of the samples, a solenoid of 3 cm in diameter, length of 10 cm and 2000 of windings was made. The empty solenoid magnetic induction was measured as a function of applied current ranging from 210 A and as a function of horizontal distance of 15 mm from the the solenoid ends. Total magnetic induction (samples and concentrates) was measured for the applied currents of 6 A. The results showed that the highest magnetic degree obtained from the sample number 7e that is 2.54% and the lowest level obtained from the sample number 3 that is 0.17%. The highest magnetic susceptibility value obtained from the sample number 7b was is 9158.12 , and the lowest magnetic susceptibility value obtained from the sample number 2 with the value of 3125.52 . Based on the mass susceptibility values of the concentrate obtained that the sand and dust along the road Kartama Pekanbaru which are in the interval 4.6 to 8.0, they implies that the mass susceptibility of the samples is in the range of Ilmenite phase FeTiO3or antiferromagnetic.

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Application of mineral magnetism to describe profile development of toposequences of a sedimentary soil in south-eastern Australia

Soil Research ◽

10.1071/sr00077 ◽

2001 ◽

Vol 39 (5) ◽

pp. 927 ◽

Cited By ~ 9

Author(s):

R. H. Crockford ◽

I. R. Willett

Keyword(s):

Particle Size ◽

Grain Size ◽

Magnetic Susceptibility ◽

Magnetic Particles ◽

Size Range ◽

The Other ◽

Particle Sizes ◽

Mineral Magnetism ◽

Particle Size Range ◽

Eastern Australia

Mineral magnetism and chemical properties of soil profiles across a valley with an erosion gully in a Yellow Dermosol sedimentary soil suggest that the magnetic profile resulted from a combination of alluviation and pedogenesis. The concentration of soil magnetic minerals in a range of particle sizes (3.36–2 mm to <2 μm) diminished from the surface downwards to a minimum (referred to as layer P), then increased to high values (layer H), after which it decreased to bed rock level at the base layer. It is proposed that the H layer was the surface of a buried soil, and that the ferrimagnetic mineral through the profiles was dominantly maghemite, formed by fire enhancement. The magnetic pattern of the profiles compressed as the soil became shallower up-slope, from 3 m in depth at the lowest site to 0.7 m at a site 40 m up-slope. Above this site the high susceptibility H layer was absent, which is consistent with the H layer being an earlier soil surface. Except for the profile at the very top of the slope (depth of 0.63 m), the magnetic grain size did not vary with depth. In the P layers, there was a greater proportion of paramagnetic minerals than in the other layers. The changes in magnetic susceptibility through the profiles were influenced by ferrimagnetic, paramagnetic, and canted anti-ferromagnetic material. For all depths in all profiles the magnetic susceptibility changed consistently through the particle size range, decreasing from the larger sizes to the 10–20 m size then increasing slightly to the smallest size (<2 μm). The mean magnetic grain size also decreased through the particle size range. Magnetic particles of 3 concentration levels were extracted by a hand magnet from the 4 largest particle sizes and showed the same magnetic-particle size relationships, for both mass susceptibility and magnetic grain size, as the other particle sizes. This showed that the proportion of highly magnetic particles effectively determined the susceptibility and magnetic grain size features of the bulk samples of each particle size class. The particle size/magnetic susceptibility pattern described in this paper occurs in all sedimentary soils and derived river sediments studied in this part of Australia. However, soils and sediments of granitic origin have an inverse pattern. These differences are attributed to pedogenic and geomorphological process. The difficulties in using mineral magnetic properties as a means of sourcing mobile sediments in catchments are discussed.

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Waste Bread as Main Ingredient for Cookie Elaboration

Foods ◽

10.3390/foods10081759 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1759

Author(s):

Priscila Guerra-Oliveira ◽

Mayara Belorio ◽

Manuel Gómez

Keyword(s):

Particle Size ◽

Elastic Modulus ◽

Wheat Flour ◽

Dough Rheology ◽

Particle Sizes ◽

Main Ingredient ◽

Spreading Factor ◽

Whole Wheat ◽

Viscous Modulus ◽

A Current

Food waste is a current global problem. The aim of this work was to investigate the possibility of reintroducing bread discarded by retailers in the preparation of sugar-snap cookies. Bread flours were obtained from stale breads (white and whole wheat) milled with 200, 500 and 1000 μm sieves. Cookies were elaborated using 100% bread flours and combinations of 50% of bread flour and wheat flour. The rheology of the doughs, the dimensions of the cookies, their texture and colour were evaluated. Bread flour doughs presented higher G’ (elastic modulus), G” (viscous modulus) values than the control, especially with increased particle size. Bread flour cookies had a smaller diameter and a harder texture than the control, but in the case of whole bread flours of larger particle sizes, those differences were reduced. Cookies made with bread flour had a darker colour and higher a* values. The 50% mixtures did not present significant differences with respect to the control in terms of dough rheology, hardness, or lightness. Although the spreading factor was reduced, it was more similar to the control than to 100% bread flour cookies. Wasted bread flour can thus be used to replace wheat flour in cookie formulations.

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The preparation and characterization of iron trihydroxide, Fe(OH)3

Canadian Journal of Chemistry ◽

10.1139/v85-557 ◽

1985 ◽

Vol 63 (12) ◽

pp. 3378-3385 ◽

Cited By ~ 10

Author(s):

Steve C. F. Au-Yeung ◽

Donald R. Eaton ◽

Thomas Birchall ◽

George Dénès ◽

John E. Greedan ◽

...

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Magnetic Susceptibility ◽

Acid Solution ◽

Size Variation ◽

Basic Solution ◽

Particle Sizes ◽

Hyperfine Fields ◽

X Ray

Iron trihydroxide has been prepared by the oxidation of FeSO4 with [Co(III)(en)(dien)]2O2[ClO4]4, [Co(III)(tetraen)]2O2[ClO4]4, and H2O2 in acid solution. These materials have been characterized by DTA, magnetic susceptibility, Mössbauer spectroscopy. X-ray powder diffraction, and electron microscopy. Particle sizes are found to be ~80 Å in diameter, but in the case of the (tetraen) preparation we find needle-like crystallites ~1200 Å × 400 Å × 50 Å in size. The magnitudes of the hyperfine fields follow the particle size variation. These materials have quite a different behaviour from the Fe(OH)3 gels prepared from basic solution.

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The Effect of Powder Particle Size on the Structural and Magnetic Properties of Bonded NdFeB Magnet

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1123.88 ◽

2015 ◽

Vol 1123 ◽

pp. 88-91 ◽

Cited By ~ 1

Author(s):

Didik Aryanto ◽

Zailani Ray ◽

Toto Sudiro ◽

Agus Sukarto Wismogroho ◽

Nanang Sudrajat

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Powder Particle Size ◽

Particle Sizes ◽

X Ray Diffraction ◽

Ndfeb Magnet ◽

Particle Size Range ◽

X Ray ◽

Diffraction Peaks ◽

Powder Type

Commercially, NdFeB powder (type MQP-B+) with difference in particle sizes were used in this study. The powders were isotropically compressed and heat cured at 150°C for 30 minute. The samples were then magnetized and characterized by impulse magnetizer K series and permagraph MAGNET-PHYSIK Dr. Steingroever GmbH, respectively. According to the results of SEM characterization, compacted powder showed a homogeneous plate distribution. The surface morphology also indicated the presence of pores in the bonded NdFeB magnet. X-ray diffraction analysis from all samples revealed that the diffraction peaks were detected as tetragonal Nd2Fe14B-phase. There was no significant different in magnetic properties of bonded magnets with different in particle size. The optimum Br, Hcb, and (BH)max were achieved at particle size range of 150-297 mm.

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

TAPPI Journal ◽

10.32964/tj14.9.565 ◽

2015 ◽

Vol 14 (9) ◽

pp. 565-576 ◽

Cited By ~ 1

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.

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

Scientific Reports ◽

10.1038/s41598-021-95769-y ◽

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.

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MAGNETIC PROPERTIES OF PSEUDO-BINARY Mn1−xFexSn2 ALLOYS

International Journal of Modern Physics B ◽

10.1142/s0217979293001852 ◽

1993 ◽

Vol 07 (01n03) ◽

pp. 867-870 ◽

Cited By ~ 3

Author(s):

H. SHIRAISHI ◽

T. HORI ◽

Y. YAMAGUCHI ◽

S. FUNAHASHI ◽

K. KANEMATSU

Keyword(s):

Field Theory ◽

Phase Diagram ◽

Magnetic Properties ◽

Magnetic Susceptibility ◽

High Temperature ◽

Magnetic Structure ◽

Magnetic Phase ◽

Magnetic Phase Diagram ◽

Molecular Field ◽

Magnetic Phases

The magnetic susceptibility measurements have been made on antiferromagnetic compounds Mn1–xFexSn2 and the magnetic phase diagram was illustrated. The high temperature magnetic phases I and III, major phases, were analyzed on the basis of molecular field theory and explained the change of magnetic structure I⇌III occured at x≈0.8.

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