Structure and magnetic properties of (Fe2O3)n clusters (n = 1–5)

2014 ◽  
Vol 16 (48) ◽  
pp. 26421-26426 ◽  
Author(s):  
A. Erlebach ◽  
C. Hühn ◽  
R. Jana ◽  
M. Sierka
Keyword(s):  
Magnetic Properties ◽  
Global Minimum ◽  
Size Range ◽  
Weak Dependence ◽  
Relative Stabilities ◽  
Magnetic States ◽  
First Time

Global minimum structures of (Fe2O3)n clusters (n = 1–5) determined for the first time in this size range show weak dependence of the structure and relative stabilities of different isomers on their magnetic states.

Structures and relative stabilities of ammonia clusters at different temperatures: DFT vs. ab initio

2015 ◽  
Vol 17 (43) ◽  
pp. 29226-29242 ◽  
Author(s):  
Alhadji Malloum ◽  
Jean Jules Fifen ◽  
Zoubeida Dhaouadi ◽  
Serge Guy Nana Engo ◽  
Nejm-Eddine Jaidane
Keyword(s):  
Ab Initio ◽  
Global Minimum ◽  
Minimum Energy ◽  
Relative Stabilities ◽  
Different Temperatures ◽  
First Time ◽  
Ammonia Clusters

The global minimum energy structures of (NH3)n=2–10are pointed out for the first time at a given temperature.

ON THE PROCESSING OF HEMATITE RAW MATERIALS AT THE KRYVOROZHSK MINING AND PROCESSING PLANT OF OXIDIZED ORE ON TECHNOLOGY OF DIRECT RECOVERY ITmk3

2018 ◽  
pp. 32-37
Author(s):  
P.I. Loboda ◽  
Younes Razaz ◽  
S. Grishchenko
Keyword(s):  
Magnetic Properties ◽  
Cast Iron ◽  
Iron Content ◽  
Raw Materials ◽  
Direct Reduction ◽  
Processing Plant ◽  
High Iron Content ◽  
High Iron ◽  
Direct Restoration ◽  
First Time

Purpose. To substantiate the efficiency of processing hematite raw materials at the Krivoy Rog Mining and Processing Plant of Oxidized Ores using the direct reduction technology itmk3®. Metodology. Analysis of the results of the itmk3® direct restoration technology developed by Kobe Steel Ltd., Japan and Hares Engineering GmbX, Austria, with a view to using it to process Krivbass hematite ores into granulated iron (so-called “nuggets”). Findings. The involvement in the production of hematite ores (oxidized quartzite) of Krivbass with high iron content, but with low magnetic properties for their processing into granular cast iron is grounded. Originality. The use of itmk3® direct reduction technology from Kobe Steel Ltd., Japan and Hares Engineering GmbH, Austria for the processing of Krivbass hematite ores into granular cast iron is justified for the first time. Practical value. The efficiency of the use of hematite ores (oxidized quartzite) has been substantiated, which can significantly reduce the costs in the mining cycle for the economical production of metallurgical products.

scholarly journals Structural, Superconducting and Magnetic Properties of La3-XRxNi2B2N3-δ with R = Ce, Pr, Nd

2011 ◽  
Vol 170 ◽  
pp. 165-169 ◽  
Author(s):  
Tahir Ali ◽  
Ernst Bauer ◽  
Gerfried Hilscher ◽  
Herwig Michor
Keyword(s):  
Magnetic Properties ◽  
Structure Type ◽  
The Body ◽  
Spin Reorientation ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Range Magnetic Order ◽  
Long Range Magnetic Order ◽  
First Time ◽  
Magnetic Pair

We report on structural and superconducting properties of La3-xRxNi2B2N3- where La is substituted by the magnetic rare-earth elements Ce, Pr, Nd. The compounds Pr3Ni2B2N3- and Nd3Ni2B2N3- are characterized for the first time. Powder X-ray diffraction confirmed all samples R3Ni2B2N3- with R = La, Ce, Pr, Nd and their solid solutions to crystallize in the body centered tetragonal La3Ni2B2N3 structure type. Superconducting and magnetic properties of La3-xRxNi2B2N3- were studied by resistivity, specific heat and susceptibility measurements. While La3Ni2B2N3- has a superconducting transition temperature Tc ~ 14 K, substitution of La by Ce, Pr, and Nd leads to magnetic pair breaking and, thus, to a gradual suppression of superconductivity. Pr3Ni2B2N3- exibits no long range magnetic order down to 2 K, Nd3Ni2B2N3- shows ferrimagnetic ordering below TC =17 K and a spin reorientation transition to a nearly antiferromagnetic state at 10 K.

scholarly journals Bio-inspired silver selenide nano-chalcogens using aqueous extract of Melilotus officinalis with biological activities

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Seyedeh Zahra Mirzaei ◽  
Hamed Esmaeil Lashgarian ◽  
Maryam Karkhane ◽  
Kiana Shahzamani ◽  
Alaa Kamil Alhameedawi ◽  
...  
Keyword(s):  
Aqueous Extract ◽  
Biomedical Applications ◽  
Size Range ◽  
Biological Activities ◽  
Spherical Shape ◽  
Silver Selenide ◽  
Melilotus Officinalis ◽  
Uv Visible ◽  
Dpph Scavenging ◽  
First Time

AbstractFor the first time, an aqueous extract of Melilotus officinalis was used to synthesize bimetallic silver selenide chalcogenide nanostructures (Ag2Se-NCs). The formation of NCs was confirmed and characterized by UV–visible and FTIR spectroscopy, SEM and TEM imaging, XRD and EDX crystallography, zeta potential (ZP) and size distribution (DLS). The bioactivities of biosynthesized Ag2Se-NCs, such as antibacterial, antibiofilm, antioxidant and cytotoxicity potentials, were then examined. Bio-based Ag2Se-NCs were successfully synthesized with mostly spherical shape in the size range of 20–40 nm. Additionally, the MIC and MBC values of Ag2Se-NCs against β-lactam-resistant Pseudomonas aeruginosa (ATCC 27853) were 3.12 and 50 µg/ml, respectively. The DPPH scavenging potential of Ag2Se-NCs in terms of IC50 was estimated to be 58.52. Green-synthesized Ag2Se-NCs have been shown to have promising benefits and could be used for biomedical applications. Although the findings indicate promising bioactivity of Ag2Se-NCs synthesized by M. officinalis extract (MO), more studies are required to clarify the comprehensive mechanistic biological activities.

scholarly journals Calcite production by Coccolithophores in the South East Pacific Ocean: from desert to jungle

2007 ◽  
Vol 4 (5) ◽  
pp. 3267-3299 ◽  
Author(s):  
L. Beaufort ◽  
M. Couapel ◽  
N. Buchet ◽  
H. Claustre
Keyword(s):  
Size Range ◽  
Digital Camera ◽  
Euphotic Zone ◽  
The South ◽  
Carbonate Ions ◽  
East Pacific ◽  
Standing Stocks ◽  
South Pacific Gyre ◽  
East Pacific Ocean ◽  
First Time

Abstract. BIOSOPE cruise achieved an oceanographic transect from the Marquise Islands to the Peru-Chili upwelling (PCU) via the centre of the South Pacific Gyre (SPG). Water samples from 6 depths in the euphotic zone were collected at 20 stations. The concentrations of suspended calcite particles, coccolithophores cells and detached coccoliths were estimated together with size and weight using an automatic polarizing microscope, a digital camera, and a collection of softwares performing morphometry and pattern recognition. Some of these softwares are new and described here for the first time. The coccolithophores standing stocks are usually low and reach maxima west of the PCU. The coccoliths of Emiliania huxleyi, Gephyrocapsa spp. and Crenalithus spp. (Order Isochrysidales) represent 50% of all the suspended calcite particles detected in the size range 0.1–46 μm (21% of PIC in term of the calcite weight). The latter species are found to grow preferentially in the Chlorophyll maximum zone. In the SPG their maximum concentrations was found to occur between 150 and 200 m, which is very deep for these taxa. The weight and size of coccoliths and coccospheres are correlated. Large and heavy coccoliths and coccospheres are found in the regions with relative higher fertility in the Marquises Island and in the PCU. Small and light coccoliths and coccospheres are found west of the PCU. This distribution may correspond to that of the concentration of calcium and carbonate ions.

Magnetic behaviors of Ti50Zr33Ni17 quasicrystals measured by VSM

2009 ◽  
Vol 224 (1-2) ◽  
Author(s):  
Yunman Lee ◽  
Jae-kyun Jeon ◽  
Hyemin Shin ◽  
Jae-yong Kim
Keyword(s):  
Magnetic Properties ◽  
Spin Glass ◽  
Rapid Quenching ◽  
Aperiodic Structure ◽  
Quenching Method ◽  
Magnetic States

AbstractQuasicrystals made with Ti, Zr and Ni are good candidate materials studying the magnetic properties of aperiodic structure because the role of Ni in stabilization of the quasicrystal phase is important. Various magnetic states in quasicrystals have been reported including diamagnetism, paramagnetism, spin glass, ferromagnetism and ferrimagnetism. We prepared Ti–Zr–Ni quasicrystals by rapid quenching method. The magnetization (

Ferromagnetic Properties of Spark-Processed Photoluminescing Silicon

1996 ◽  
Vol 452 ◽  
Author(s):  
J. Hack ◽  
M. H. Ludwig ◽  
W. Geerts ◽  
R. E. Hummel
Keyword(s):  
Magnetic Properties ◽  
High Purity ◽  
Paramagnetic Centers ◽  
Bulk Silicon ◽  
High Concentration ◽  
Temperature Dependent ◽  
Paramagnetic Resonance ◽  
Ultra High Purity ◽  
Ferromagnetic Ordering ◽  
First Time

AbstractMagnetic properties of photoluminescing spark-processed silicon (sp-Si) have been investigated for the first time. Contrary to the diamagnetic signal known for bulk silicon, sp-Si displays a paramagnetic resonance as well as a ferromagnetic hysterisis loop. The paramagnetic resonance was studied using an EPR system and showed a high concentration of at least two distinct paramagnetic centers. One center can be eliminated by annealing in Ultra-High Purity nitrogen for 30 minutes at 600 °C. Measurements utilizing a SQUID magnetometer revealed that sp-Si displays ferromagnetic ordering with a saturization magnetization occuring at low fields. This is attributed to the high density of paramagnetic centers. Temperature dependent measurements were performed to establish possible links between magnetic properties and the luminescence of sp-Si.

Sol Freeze Dry Nd:YAG Nanopowder Synthesis and Sinterability Studies

2015 ◽  
Vol 65 (5) ◽  
pp. 418
Author(s):  
Rekha Mann ◽  
Kiranmala Laishram ◽  
Sheikh Ashfaq Ahmed ◽  
Khavangkhui Zimik ◽  
Neelam Malhan
Keyword(s):  
Citric Acid ◽  
Metal Ion ◽  
Size Range ◽  
Molar Ratio ◽  
Yttrium Aluminium ◽  
Acid Ratio ◽  
Freeze Dried ◽  
Phase Pure ◽  
First Time ◽  
Nanopowder Synthesis

<p>Citrate nitrate sol freeze dry synthesis of 2 atomic % neodymium ion doped Yttrium Aluminium Oxide (Nd:YAG) nanopowders was explored for the first time. Sol was prepared by dissolving nitrates of Al3+, Y3+ and Nd3+ keeping molar ratio to be 5: 2.94: 0.06. Total metal ion to citric acid ratio was optimised at 1 is to 0.25. Sol was freeze dried at -80 °C for 48 h. Dried mass thus obtained was calcined at 1000 °C for 2 h to give phase pure Nd:YAG as characterised by FTIR and XRD. Particles were in the size range of 35 nm - 50 nm with close to spherical morphology as observed by TEM. Nanopowder was compacted and sintered at 1700 °C for 5 h under 10-6 mbar followed by hot isostatic press at 1750 °C for 4 h under 200 MPa, to give 71 per cent transmission at 1064 nm indicating synthesis of well sinterable Nd:YAG nanopowders.</p>

scholarly journals Password-free Authentication for Smartphone Touchscreen Based on Finger Size Pattern

2020 ◽  
Vol 14 (19) ◽  
pp. 163
Author(s):  
Yaser Ali Enaya ◽  
Mohammed Jawad Mohammed
Keyword(s):  
Data Mining ◽  
Pattern Recognition ◽  
Size Range ◽  
Training Set ◽  
Evaluation Approach ◽  
Frequency Position ◽  
Data Files ◽  
A New Technique ◽  
First Time ◽  
Authentication Technique

This study introduces a novel authentication methodology; it is based on pattern recognition of fingers size and pressure when users touch smartphone screen. By analyzing diagrams of these touches and applying data mining for the first time as an authentication technique, this paper presents three new approaches. First, an exact-range evaluation approach has been verified that size is more recognition consistency than pressure. Second, a pattern-range is a new technique reliance on size frequency position. At last, using a size-range has been facilitated the login. The association rules have been modified to work on finger touchscreen data files. To login, 94.1111% of 18 authorized users are succeeded and 98.9% of 20 unauthorized users are failed. Android device and Android studio are used. Size and pressure are normalized to 1; a training set is applied; the password is not considered.

Sign in / Sign up

Export Citation Format

Share Document