Crystal Polymorphs and Multiple Crystallization Pathways of Highly Pressurized 1-Ethyl-3-Methylimidazolium Nitrate

2019 ◽  
Vol 72 (2) ◽  
pp. 87 ◽  
Author(s):  
Hiroshi Abe ◽  
Takahiro Takekiyo ◽  
Yukihiro Yoshimura ◽  
Nozomu Hamaya ◽  
Shinichiro Ozawa
Keyword(s):  
Differential Scanning Calorimetry ◽  
High Pressure ◽  
Room Temperature ◽  
Ambient Pressure ◽  
Optical Microscope ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Low Temperature Crystallization ◽  
Temperature Crystallization

Crystal polymorphs and multiple crystallization pathways of a room-temperature ionic liquid (RTIL) were observed only under high pressure (HP). The RTIL was 1-ethyl-3-methylimidazolium nitrate, [C2mim][NO3]. The HP-crystal polymorphs were related to conformations of the C2mim+ cation, and the HP-crystal pathways determined by the presence or absence of the planar′ (P′) conformation of the C2mim+ cation were switched at the bifurcation pressure (PB). Above PB, modulated crystal structures derived from the HP-inherent P′ conformer. Simultaneous X-ray diffraction and differential scanning calorimetry measurements, accompanied by optical microscope observations, confirmed the normal low-temperature crystallization of [C2mim][NO3] under ambient pressure.

Influence of Gd Addition on the Structure and Capability of Ni-Mn-In Metamagnetic Shape Memory Alloys

2012 ◽  
Vol 535-537 ◽  
pp. 950-953
Author(s):  
Li Na Bai ◽  
Gui Xing Zheng ◽  
Zhi Jian Duan ◽  
Jian Jun Zhang
Keyword(s):  
Differential Scanning Calorimetry ◽  
Magnetic Properties ◽  
Magnetic Property ◽  
Transition Temperature ◽  
Martensitic Transformation ◽  
Room Temperature ◽  
Vibrating Sample Magnetometry ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

The influences of Gd concentration on martensitic transformation and magnetic properties of NiMnIn alloys were investigated by differential scanning calorimetry (DSC) , vibrating sample magnetometry (VSM), X-ray diffraction (XRD) and etc. It is Observed through the experiment: the addition of Gd enhances martensite transition temperature;X-ray diffraction analysis of experimental alloys is revealed that to the mixture is martensite and austenite at room temperature; content of Gd is not proportional to the improvement of magnetic property.

Study of thermal properties of Ga0.5In1.5Se3 by differential scanning calorimetry

2021 ◽  
pp. 2150407
Author(s):  
S. I. Ibrahimova
Keyword(s):  
Crystal Structure ◽  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Thermal Effects ◽  
Room Temperature ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
Hexagonal Symmetry ◽  
Scanning Calorimetry ◽  
X Ray

The crystal structure and thermal properties of the [Formula: see text] compound have been investigated. Structural studies were performed by X-ray diffraction at room temperature. The crystal structure of this compound was found to correspond to the hexagonal symmetry of the space group P61. Thermal properties were studied using a differential scanning calorimetry (DSC). It was found in the temperature range [Formula: see text] that thermal effects occur at temperatures [Formula: see text] and [Formula: see text]. The thermodynamic parameters of these effects are calculated.

scholarly journals High-Pressure Structural Behavior and Equation of State of Kagome Staircase Compound, Ni3V2O8

Crystals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 910
Author(s):  
Daniel Diaz-Anichtchenko ◽  
Robin Turnbull ◽  
Enrico Bandiello ◽  
Simone Anzellini ◽  
Daniel Errandonea
Keyword(s):  
High Pressure ◽  
Equation Of State ◽  
Density Functional ◽  
Room Temperature ◽  
Ambient Pressure ◽  
Density Functional Theory Calculations ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
A Chain

We report on high-pressure synchrotron X-ray diffraction measurements on Ni3V2O8 at room-temperature up to 23 GPa. According to this study, the ambient-pressure orthorhombic structure remains stable up to the highest pressure reached in the experiments. We have also obtained the pressure dependence of the unit-cell parameters, which reveals an anisotropic compression behavior. In addition, a room-temperature pressure–volume third-order Birch–Murnaghan equation of state has been obtained with parameters: V0 = 555.7(2) Å3, K0 = 139(3) GPa, and K0′ = 4.4(3). According to this result, Ni3V2O8 is the least compressible kagome-type vanadate. The changes of the crystal structure under compression have been related to the presence of a chain of edge-sharing NiO6 octahedral units forming kagome staircases interconnected by VO4 rigid tetrahedral units. The reported results are discussed in comparison with high-pressure X-ray diffraction results from isostructural Zn3V2O8 and density-functional theory calculations on several isostructural vanadates.

scholarly journals Stoichiometric evolutions of PH3 under high pressure: implication for high-Tc superconducting hydrides

2019 ◽  
Vol 6 (3) ◽  
pp. 524-531 ◽  
Author(s):  
Ye Yuan ◽  
Yinwei Li ◽  
Guoyong Fang ◽  
Guangtao Liu ◽  
Cuiying Pei ◽  
...  
Keyword(s):  
High Pressure ◽  
Room Temperature ◽  
Recent Observation ◽  
Theoretical Calculations ◽  
Ambient Pressure ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Elemental Phosphorus ◽  
High Tc ◽  
X Ray

Abstract The superconductivity of hydrides under high pressure has attracted a great deal of attention since the recent observation of the superconducting transition at 203 K in strongly compressed H2S. It has been realized that the stoichiometry of hydrides might change under high pressure, which is crucial in understanding the superconducting mechanism. In this study, PH3 was studied to understand its superconducting transition and stoichiometry under high pressure using Raman, IR and X-ray diffraction measurements, as well as theoretical calculations. PH3 is stable below 11.7 GPa and then it starts to dehydrogenate through two dimerization processes at room temperature and pressures up to 25 GPa. Two resulting phosphorus hydrides, P2H4 and P4H6, were verified experimentally and can be recovered to ambient pressure. Under further compression above 35 GPa, the P4H6 directly decomposed into elemental phosphorus. Low temperature can greatly hinder polymerization/decomposition under high pressure and retains P4H6 up to at least 205 GPa. The superconductivity transition temperature of P4H6 is predicted to be 67 K at 200 GPa, which agrees with the reported result, suggesting that it might be responsible for superconductivity at higher pressures. Our results clearly show that P2H4 and P4H6 are the only stable P–H compounds between PH3 and elemental phosphorus, which is helpful for shedding light on the superconducting mechanism.

Adjusting Microstructure and Magnetic Properties of Ni-Mn-In Metamagnetic Shape Memory Alloys by Addition of Gd

2012 ◽  
Vol 535-537 ◽  
pp. 959-963
Author(s):  
Li Na Bai ◽  
Gui Xing Zheng ◽  
Jing Xin ◽  
Jian Jun Zhang
Keyword(s):  
Magnetic Field ◽  
Differential Scanning Calorimetry ◽  
Magnetic Properties ◽  
Shape Memory ◽  
Room Temperature ◽  
Vibrating Sample Magnetometry ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Microstructure And Magnetic Properties

The influences of Gd concentration on martensitic transformation and magnetic properties of NiMnIn alloys were investigated by differential scanning calorimetry (DSC) , vibrating sample magnetometry (VSM), X-ray diffraction (XRD) and etc. It shows that addition of Gd enhances martensite transition temperature and that X-ray diffraction analysis of experimental alloys is revealed which the mixture is martensite and austenite at room temperature. These alloys show promise as a metamagnetic shape memory alloy with magnetic-field-induced shape memory effect.

Synthesis of pure amorphous Fe2O3

1997 ◽  
Vol 12 (2) ◽  
pp. 402-406 ◽  
Author(s):  
X. Cao ◽  
R. Prozorov ◽  
Yu. Koltypin ◽  
G. Kataby ◽  
I. Felner ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Particle Size ◽  
Room Temperature ◽  
Nitrogen Atmosphere ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Air Atmosphere ◽  
Transmission Electron ◽  
Amorphous Nanoparticles

A method for the preparation of pure amorphous Fe2O3 powder with particle size of 25 nm is reported in this article. Pure amorphous Fe2O3 can be simply synthesized by the sonication of neat Fe(CO)5 or its solution in decalin under an air atmosphere. The Fe2O3 nanoparticles are converted to crystalline Fe3O4 nanoparticles when heated to 420 °C under vacuum or when heated to the same temperature under a nitrogen atmosphere. The crystalline Fe3O4 nanoparticles were characterized by x-ray diffraction and M¨ossbauer spectroscopy. The Fe2O3 amorphous nanoparticles were examined by Transmission Electron Micrography (TEM), Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), and Quantum Design SQUID magnetization measurements. The magnetization of pure amorphous Fe2O3 at room temperature is very low (<1.5 emu/g) and it crystallizes at 268 °C.

scholarly journals Crystal Structures and Thermal Properties of L-MnC4H4O6•2H2O and DL-MnC4H4O6•2H2O

2019 ◽  
Vol 12 (1) ◽  
pp. 78
Author(s):  
Takanori Fukami ◽  
Shuta Tahara ◽  
Arbi Dimyati
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Room Temperature ◽  
Structural Parameters ◽  
Silica Gels ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Weight Losses ◽  
Group Symmetries

Manganese L-tartrate dihydrate, L-MnC4H4O6&middot;2H2O, and manganese DL-tartrate dihydrate, DL-MnC4H4O6&middot;2H2O, crystals were grown at room temperature by the gel method using silica gels as the growth medium. Differential scanning calorimetry, thermogravimetric-differential thermal analysis, and X-ray diffraction measurements were performed on both crystals. The space group symmetries (monoclinic P21 and P2/c) and structural parameters of the crystals were determined at room temperature. Both structures consisted of slightly distorted MnO6 octahedra, C4H4O6 and H2O molecules, and O&ndash;H&middot;&middot;&middot;O hydrogen-bonding frameworks between adjacent molecules. Weight losses due to thermal decomposition of the crystals were found to occur in the temperature range of 300&ndash;1150 K. We inferred that the weight losses were caused by the evaporation of bound 2H2O molecules, and the evolutions of gases from C4H4O4 and of (1/2)O2 gas from MnO2, and that the residual black substance left in the vessels after decomposition was manganese oxide (MnO).

X-ray diffraction and differential scanning calorimetry investigations on high-pressure hydrogen gas charged Ti3Al

2000 ◽  
Vol 312 (1-2) ◽  
pp. 251-256 ◽  
Author(s):  
D Sornadurai ◽  
B.K Panigrahi ◽  
K Shashikala ◽  
P Raj ◽  
V.S Sastry ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
High Pressure ◽  
Hydrogen Gas ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Pressure Hydrogen

The effect of plastic deformation at near room temperature on the solid state reactions between Ni and Sn

1991 ◽  
Vol 6 (3) ◽  
pp. 499-504 ◽  
Author(s):  
S. Martelli ◽  
G. Mazzone ◽  
M. Vittori-Antisari
Keyword(s):  
Differential Scanning Calorimetry ◽  
Plastic Deformation ◽  
Solid State ◽  
Thermal Treatment ◽  
Room Temperature ◽  
Metastable Phases ◽  
Solid State Reactions ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

Solid state reactions between Ni and Sn at two compositions, Ni75Sn25 and Ni60Sn40, have been induced by means of near room temperature cold rolling and mechanical alloying. The reaction steps have been monitored by x-ray diffraction and differential scanning calorimetry. At both compositions, the first effect of plastic deformation is the formation of two metastable phases which, by further milling or low temperature thermal treatment, transform into the Ni3Sn4 compound. The chemical composition of the metastable phases has been determined to be close to that of Ni3Sn4 and the crystal structure of one of them appears to be related to that of β–Sn. Differential scanning calorimetry and thermal treatment of samples containing the metastable phases have shown that these phases transform into Ni3Sn4 at about 150 °C and that no other reaction takes place up to this temperature. Upon prolonged milling, a different behavior has been observed for the two compositions. While the Ni60Sn40 mixture eventually forms the Ni3Sn2 compound in agreement with previous results, the final product of mechanically alloying the Ni75Sn25 mixture is a phase whose structure, rather than amorphous as previously hypothesized, in our case can be described as based on that of the disordered high temperature form of the Ni3Sn compound. Differential scanning calorimetry and x-ray diffraction analysis of this sample have shown the formation, at 380 °C, of ordered Ni3Sn with an associated heat release of about 10 kJ/mole.

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