scholarly journals Studi Teoritis Pembentukan Momen Magnetik pada Alloy half-Heusler Mn2Ge

2019 ◽  
Vol 2 (1) ◽  
pp. 34-39
Author(s):  
Anugrah Azhar ◽  
Muhammad Aziz Majidi
Keyword(s):  
Magnetic Moment ◽  
Theoretical Study ◽  
Simple Calculation ◽  
Spin Orientation ◽  
Metallic Behavior ◽  
Metal Compounds ◽  
Spin Channel ◽  
A Value ◽  
Minority Spin ◽  
The One

Heusler alloyalloy is a subclass material that consists of transition metal compounds with fascinating magnetic properties due to their magnetic moment value  that is still studied by many researchers due to their magnetic moment value that can be predicted using a simple calculation called Slater-Pauling rule (SP rule)s. According to the SP rule, when the total number of the valance electron gives a value of 18 (for half-Heusler alloy), the magnetic momen of this material is predicted by the value of 0 μB. By using this simple calculation, one can make material that have zero magnetic moment value. On the other hand, those this materials generally hasve halfhalf-metallic behavior in which the spin orientation only occurs on the one direction of either in the majority or minority spin channel. Starting from those issues, we propose a theoretical study to investigate the magnetic moment formation of halfhalf-Heusler alloyalloy Mn2Ge. Our results show that Mn2Ge have magnetic moment of 0.03 μB and show the halfhalf-metallic feature of Mn2Ge. 

scholarly journals First principles calculations for electronic, optical and magnetic properties of full heusler compounds

2020 ◽  
Keyword(s):  
Magnetic Properties ◽  
Band Gap ◽  
Magnetic Moment ◽  
Magnetic Moments ◽  
Potential Method ◽  
Full Potential ◽  
Metallic Behavior ◽  
Optical Phenomenon ◽  
Minority Spin ◽  
Optical And Magnetic Properties

For the investigation of structural, electronic, optical and magnetic properties of Co2CrZ (Z= In, Sb, Sn) compounds, we have used two different methods. One is based on full potential linearized augmented plane wave (FP-LAPW) method as implemented in WIEN2k and second is pseudo potential method as implemented in Atomistic Tool Kit-Virtual NanoLab (ATK-VNL). These compounds show zero band gap in their majority-spin and minority-spin representing metallic behavior except the compound Co2CrSb, which is showing the band gap 0.54 eV in their minority-spin near the Fermi level and viewing 100% spin polarization; which is implemented in WIEN2k code. Further, the compound Co2CrSb has been found to be perfectly half-metallic ferromagnetic (HMF). However, above mentioned compounds shows zero band gap in ATK-VNL code. Calculations performed using WIEN2k code shows the magnetic moment of these compounds Co2CrZ (Z= In, Sb, Sn) 3.11, 5.00 and 4.00µB respectively. However, the respective magnetic moment of these compounds is found to be 3.14, 5.05 and 4.12µB in ATK-VNL code. Calculated magnetic moments have good agreement with the Slater-Pauling behavior. Optical properties play an important role to understand the nature of material for optical phenomenon and optoelectronics devices. Value of absorption coefficient and optical conductivity of Co2CrSb is greatest than other two compounds. From the absorption and reflection spectra relation, observations indicate that absorption and reflectivity are inversely proportional to each other.

ANALISIS VARIASI JUMLAH SUDU TURBIN BERPENAMPANG PELAT DATAR PADA TURBIN AIR ALIRAN VORTEX DENGAN TIPE SALURAN MASUK INVOLUTE

2020 ◽  
Vol 7 (2) ◽  
pp. 72-78
Author(s):  
Adnan Al Farisi ◽  
Yopi Handoyo ◽  
Taufiqur Rokhman
Keyword(s):  
Power Plant ◽  
Alternative Energy ◽  
Vortex Flow ◽  
Experimental Methods ◽  
Turbine Efficiency ◽  
A Value ◽  
Current Voltage ◽  
Materials Research ◽  
The One ◽  
Flow Vortex

The One of alternative energy that is environmentally friendly is by untilize water energy and turn it into a Microhydro power plant. Microhydro power plant usually made from utilize the waterfall with the head fell. While utilization for streams with a head small drop is not optimal yet. This is a reference to doing research on harnessing the flow of a river that has a value of head low between 0.7 m – 1.4 m with turning it into a Vortex flow (vortex). The purpose of this research is to know  the effect variation number of blade on power and efficiency in the vortex turbine. This research uses experimental methods to find current, voltage, torque and rpm using a reading instrument. The materials research vortex turbine used 6 blade, 8 blade and 10 blade with flat plate. The result showed the highest efficiency is 29,93 % with produce turbine power is 19,58 W, generated on turbine with variation 10 blade with load 3,315 kg and the capacity of water 10,14 l/s. Followed with an efficiency 24,17% and produce turbine power is 15,81 W, generated on turbine with the variation 8 blade with load 3,315 kg and the capacity of water is 10,14 l/s. The the lowest turbine efficiency 22,32% with produce tuebine power 14,60 W, generated on turbine with the variation 6 blade with load 3,315 kg, the capacity of water is 10,14 l/s.

Evaluation of the Properties of Humus Liquid of Earthworm Eisenia Foetida Obtained from Different Rachis

2017 ◽  
Vol 3 (02) ◽  
Author(s):  
Ramiro Remigio Gaibor Fernández ◽  
Abraham Adalberto Bayas Zamora ◽  
Galo Israel Muñoz Sánchez ◽  
Cristhian Adrián Rivas Santacruz
Keyword(s):  
Plant Growth ◽  
Fulvic Acids ◽  
Cattle Manure ◽  
Eisenia Foetida ◽  
Humic And Fulvic Acids ◽  
Livestock Manure ◽  
A Value ◽  
The One ◽  
Liquid Slurry

The objective of the present investigation was to evaluate the physical characteristics of the vermicompost and the quality of the purine of the red Californian (Eisenia foetida) using different substrates of feed for these worms. For this purpose, nine treatments were studied: 75% African palm rachis + 25% cattle manure, 50% African palm rachis + 50% cattle manure, 25% African palm rachis + 75% livestock manure, 50% manure of cattle, 50% of manure of cattle, 25% of manure of cattle, 50% of manure of cattle, 50% of manure of cattle, 50% of rach of coconut + 50% of manure of Livestock, 25% coccus rachis + 75% livestock manure. The substrate made up of 50% of rachis of coconut and 50% of livestock manure can be used in nurseries or nurseries for being the one that registered a value of pH 7.3 plus the closest to the neutral compared to the others, besides this (75% of oil palm rachis and 25% of cattle manure) showed a higher content of humic and fulvic acids (0.87 and 0.45 p / p, respectively), compounds that are important for agriculture by stimulating plant growth, in addition to this reflection 0.06% sulfur content, 4.0 ppm boron, 7.0 ppm copper, 47.5 ppm iron, 6.0 ppm manganese, with a presence of microorganisms of the species Trichoderma, Penicillium, Cladosporium sp. in amounts of 1.91x105 UFC / ml, however in this substrate was obtained between 13.3 and 43.5% less liquid slurry in Comparison with other treatments.

Paraelektrische Resonanz und dielektrische Dispersion von Wasser in Beryll-Einkristallen / Paraelectric Resonance and Dielectric Dispersion of Water in Beryl Single Crystals

1974 ◽  
Vol 29 (11) ◽  
pp. 1558-1571
Author(s):  
H.-J. Rehm
Keyword(s):  
Electric Fields ◽  
Resonance Effect ◽  
Theoretical Description ◽  
Tunnel Effect ◽  
Zero Field ◽  
Zero Field Splitting ◽  
A Value ◽  
Axis Parallel ◽  
Electric Dipoles ◽  
The One

Paraelectric resonance spectra of beryl crystals are observed in the X-band region between 5 and 20 kV/cm under the condition that the external electric field F[101̅0]. Additional dielectric measurements show, that the paraelectric centres are the monomeric water molecules in the beryl cavities. For water dipoles in beryl only two orientations of the molecular a-axis relative to the crystal C6-axis are possible, and only those with their a-axis parallel to the C6-axis contribute to the paraelectric resonance effect. The electric moment vector µ of these latter molecules may rotate in the (0001)-crystal plane, i. e. around their own a-axis, and has a value of (1.9 ± 0.2) D. A theoretical description of paraelectric resonance is presented for a simplified model: the electric dipoles have 6 equivalent equilibrium positions along the [101̅0]-directions, tunnel effect and external electric fields remove the site degeneracy and we observe a molecular Stark splitting. We calculate a value of (2.0 ± 0.4) GHz for the zero-field splitting in the one-parameter Hamiltonian model.

Ferrimagnetic Half-Metallicity of the New Quaternary Heusler Alloy CoCrScIn: FP-LAPW Method

SPIN ◽  
2021 ◽  
Vol 11 (02) ◽  
pp. 2150017
Author(s):  
Halima Hamada ◽  
Keltouma Boudia ◽  
Friha Khelfaoui ◽  
Kadda Amara ◽  
Toufik Nouri ◽  
...  
Keyword(s):  
Magnetic Moment ◽  
Density Functional ◽  
Structural Parameters ◽  
Magnetic Transition ◽  
Plane Waves ◽  
Full Potential ◽  
Half Metallicity ◽  
Metallic Behavior ◽  
Magnetic Transition Temperature ◽  
Half Metallic

The structural, electronic, elastic and magnetic properties of CoCrScIn were investigated using first principle calculations with applying the full-potential linearized augmented plane waves (FP-LAPW) method, based totally on the density functional theory (DFT). After evaluating the results, the calculated structural parameters reveal that CoCrScIn compound is stable in its ferrimagnetic configuration of the type-III structure. The mechanical properties show its brittle and stiffer behavior. The formation energy value showed that CoCrScIn can be experimentally synthesized. Additionally, the obtained band structures and density of states (DOS) reflect the half-metallic behavior of CoCrScIn, with an indirect bandgap of 0.43[Formula: see text]eV. The total magnetic moment of 3[Formula: see text][Formula: see text] and half-metallic ferrimagnetic state are maintained in the range 5.73–6,79 Å. The magnetic moment especially issues from the Cr-[Formula: see text] and Co-[Formula: see text] spin-polarizations. Furthermore, the calculations of Curie temperature reveal that CoCrScIn has high magnetic transition temperature of 836.7[Formula: see text]K.

scholarly journals Toxicity of neem's oil, a potential biocide against the invasive mussel Limnoperna fortunei (Dunker 1857)

2012 ◽  
Vol 84 (4) ◽  
pp. 1065-1071 ◽  
Author(s):  
Patricio J. Pereyra ◽  
Gustavo B. Rossini ◽  
Gustavo Darrigran
Keyword(s):  
Invasive Species ◽  
Toxicity Tests ◽  
Limnoperna Fortunei ◽  
Target Species ◽  
Potential Toxicity ◽  
A Value ◽  
Closed Systems ◽  
The One ◽  
Invasive Mussel ◽  
Golden Mussel

The golden mussel Limnoperna fortunei (Dunker 1857) is one of the most distributed Nuisance Invasive Species (NIS) in South America, and a threat of great concern for the industry of the area. In this study, we carried out toxicity tests made with a Neem's oil solution with L. fortunei larvae and benthonic adults (7, 13 and 19 ± 1 mm). Tests with non-target species (Daphnia magna, Lactuca sativa and Cnesterodon decemmculatus) were also made with the aim to evaluate the potential toxicity of the Neem's solution in the environment. The LC100 of Neem's solution obtained for larvae was 500 µl/L, a value much higher than the one obtained for D. magna and C. decemmaculatus. Thus, we recommend that it should not be used in open waters. However, since the adults were killed in 72 h and the larvae in 24 h, this product can be used in closed systems, in man-made facilities.

scholarly journals 4. On a Thermomagnetic Thermoscope

1880 ◽  
Vol 10 ◽  
pp. 538-539
Author(s):  
W. Thomson
Keyword(s):  
Magnetic Moment ◽  
Horizontal Plane ◽  
Hardened Steel ◽  
The Other ◽  
Silk Fibre ◽  
Steel Wires ◽  
The One

This thermoscope is founded on the change produced in the magnetic moment of a steel magnet by change of temperature. Several different forms suggest themselves: the one which seems best adapted to give good results is to be made as follows:—(1.) Prepare an approximately astatic system of two thin, hardened steel wires, r b, r′ b′, each 1 cm. long, one of them, r, b, hung by a single silk fibre, and the other hung bifilarly from it, by fibres about 3 cms. long, so attached that the projections of the two, on a horizontal plane, shall be inclined at an angle of about ·01 of a radian (or ·57°) to one another.

Microstructure of FCC/BCC Metal Multilayers

1989 ◽  
Vol 160 ◽  
Author(s):  
Nigel M. Jennett ◽  
D.J. Dingley ◽  
Y. Ando
Keyword(s):  
Substrate Temperature ◽  
Magnetic Moment ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Bcc Lattice ◽  
A Value ◽  
Fcc Lattice ◽  
Temperature Window ◽  
Backing Layer

AbstractBilayers of Cu/Fe and Cu/V and multilayers of Ni/Fe have been grown under high vacuum and ultra high vacuum conditions respectively with [111] epitaxy. Multilayer layer thicknesses ranged from 3 monolayers to 15 monolayers per layer. Improved epitaxy of the UHV growth was, we believe, due to the better vacuum although perfect material could only be obtained for growth within a narrow and shifting substrate temperature ‘window’. Possible shortfall in the quality of the Cu backing layer epitaxy was averted by a 2hr anneal at 425°C.In the Fe/Ni multilayers the Fe was observed to adopt the FCC lattice rather than the equilibrium BCC lattice for layer thicknesses less than 10 monolayers. This change of structure coincided with a reduction in sample magnetic moment per volume attributed to a collapse of the Fe moment to a value 7 times less than bulk.

scholarly journals Symmetry breakdown and coupling constants of leptons

2007 ◽  
Vol 79 (2) ◽  
pp. 195-208 ◽  
Author(s):  
Gil C. Marques ◽  
Dominique Spehler
Keyword(s):  
Coupling Constants ◽  
Electroweak Interactions ◽  
New Approach ◽  
Fundamental Interactions ◽  
Electromagnetic Interactions ◽  
Symmetry Breakdown ◽  
A Value ◽  
Intermediate Bosons ◽  
The One ◽  
The Way

Based on a new approach to symmetries of the fundamental interactions we deal, in this paper, with the electroweak interactions of leptons. We show that the coupling constants, arising in the way leptons are coupled to intermediate bosons, can be understood as parameters associated to the breakdown of SU(2) and parity symmetries. The breakdown of both symmetries is characterized by a new parameter (the asymetry parameter) of the electroweak interactions. This parameter gives a measure of the strength of breakdown of symmetries. We analyse the behaviour of the theory for three values of this parameter. The most relevant value is the one for which only the electromagnetic interactions do not break parity (the maximally allowed left-right asymetric theory). Maximamally allowed parity asymmetry is a requirement that is met for a value of Weinberg's theta-angle that is quite close to the experimental value of this parameter.

Sign in / Sign up

Export Citation Format

Share Document