An X-Ray diffraction analysis of low temperature structural changes in the myelin lattice

Cryobiology ◽  
1975 ◽  
Vol 12 (6) ◽  
pp. 555-556
Author(s):  
M.J. Costello ◽  
H. Bank
Keyword(s):  
Low Temperature ◽  
Diffraction Analysis ◽  
Structural Changes ◽  
X Ray Diffraction ◽  
X Ray

scholarly journals X-ray diffraction analysis of kaolin M1 and M2 via the Williamson–Hall and Warren–Averbach methods

2021 ◽  
pp. 174751982098472
Author(s):  
Lalmi Khier ◽  
Lakel Abdelghani ◽  
Belahssen Okba ◽  
Djamel Maouche ◽  
Lakel Said
Keyword(s):  
Grain Size ◽  
High Temperature ◽  
Low Temperature ◽  
Diffraction Analysis ◽  
Mechanical Resistance ◽  
X Ray Diffraction ◽  
Integral Breadth ◽  
X Ray ◽  
Mullite Phase

Kaolin M1 and M2 studied by X-ray diffraction focus on the mullite phase, which is the main phase present in both products. The Williamson–Hall and Warren–Averbach methods for determining the crystallite size and microstrains of integral breadth β are calculated by the FullProf program. The integral breadth ( β) is a mixture resulting from the microstrains and size effect, so this should be taken into account during the calculation. The Williamson–Hall chart determines whether the sample is affected by grain size or microstrain. It appears very clearly that the principal phase of the various sintered kaolins, mullite, is free from internal microstrains. It is the case of the mixtures fritted at low temperature (1200 °C) during 1 h and also the case of the mixtures of the type chamotte cooks with 1350 °C during very long times (several weeks). This result is very significant as it gives an element of explanation to a very significant quality of mullite: its mechanical resistance during uses at high temperature remains.

Study of Structural Changes in LiNi0.8Co0.1Mn0.1O2 Cathode Material for Lithium-Ion Batteries by X-Ray Diffraction Analysis in the In Situ Mode

2019 ◽  
Vol 92 (7) ◽  
pp. 1013-1019 ◽  
Author(s):  
P. A. Novikov ◽  
A. E. Kim ◽  
K. A. Pushnitsa ◽  
Wang Quingsheng ◽  
M. Yu. Maksimov ◽  
...  
Keyword(s):  
Cathode Material ◽  
Diffraction Analysis ◽  
Lithium Ion Batteries ◽  
Structural Changes ◽  
Lithium Ion ◽  
X Ray Diffraction ◽  
X Ray

scholarly journals Structural Changes in a-Si:H Films Deposited on the Edge of Crystallinity

1999 ◽  
Vol 557 ◽  
Author(s):  
A.H. Mahan ◽  
J. Yang ◽  
S. Guha ◽  
D.L. Williamson
Keyword(s):  
Low Temperature ◽  
Glow Discharge ◽  
Structural Changes ◽  
Amorphous Matrix ◽  
Volume Fraction ◽  
Peak Frequency ◽  
X Ray Diffraction ◽  
X Ray

AbstractUsing infrared, H evolution and x-ray diffraction (XRD), the structure of high H dilution, glow discharge deposited a-Si:H films ‘on the edge of crystallinity’ is examined. From the Si-H wag mode peak frequency and the XRD results, we postulate the existence of very small Si crystallites contained within the as-grown amorphous matrix, with the vast majority of the bonded H located on these crystallite surfaces. Upon annealing at ramp rates of 8-15°C/min, a H evolution peak at ~400°C appears, and film crystallization is observed at temperatures as low as 500°C, both of which are far below those observed for a-Si:H films grown without H dilution using similar rates. While the crystallite volume fraction is too small to be detected by XRD in the as-grown films, these crystallites enable the crystallization of the remainder of the amorphous matrix upon moderate annealing, thus explaining the existence of the low temperature H evolution peak.

π-Olefin-Iridium-Komplexe, XXII [1]. C-H-Aktivierung von aromatischen und aliphatischen Solvensmolekülen RH bei der Reaktion von [Cp*IrCI2]2 mit Butadienmagnesium unter Bildung von [Cp*Ir(η3-C4H7)R] sowie Kristallstruktur von [Cp*Ir(η3-C4H7)C6H5] / π-Olefin Iridium Complexes, XXII [1]. C-H Activation of Aromatic and Aliphatic Solvent Molecules RH in the Reaction of [Cp*IrCl2]2 with Butadienemagnesium with Formation of [Cp*Ir(η3-C4H7)R], and Crystal Structure of [Cp*Ir(η3-C4H7)C6H5]

1994 ◽  
Vol 49 (12) ◽  
pp. 1645-1653 ◽  
Author(s):  
Jörn Müller ◽  
Petra Escarpa Gaede ◽  
Ke Qiao
Keyword(s):  
Crystal Structure ◽  
Low Temperature ◽  
Diffraction Analysis ◽  
Iridium Complexes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nmr Spectrometry ◽  
Benzene Toluene ◽  
Solvent Molecules ◽  
Mechanism Of The Reaction

Reactions of [Cp*IrCl2]2 (Cp*=η3-C5Me5) with [MgC4H6·2 THF]n at low temperature give [Cp*Ir(η4-C4H6)] together with [Cp*Ir(η3-C4H7)R] compounds, the latter being formed via C-H activation of solvent molecules RH (RH = benzene, toluene, anisole, thiophene, furane, N-methylpyrrole, pentane, cyclohexane. THF). In the case of pyrrole, C-N -activation occurs. The ratio of syn and anti isomers of the 1-methylallyl complexes as well as the sites of C-H activation of RH were investigated by NMR spectrometry. An enantiomorphous crystal of [Cp*Ir(η3-C4H7)C6Hs] was characterized by X-ray diffraction analysis which reveals trigonal planar coordination at the Ir atom and an exo, syn conformation of the 1-methylallyl ligand. A mechanism of the reaction which involves 16-electron intermediates is discussed. The corresponding system [Cp*RhCl2]2/butadienemagnesium/RH gives only [Cp*Rh(η4-C4H6)], and no C-H activation is observed.

scholarly journals IDENTIFIKASI PERUBAHAN MINERAL SELAMA PROSES PEMANASAN PELET KOMPOSIT NIKEL DENGAN ANALISIS DIFRAKSI SINAR X ( IDENTIFICATION OF MINERAL CHANGES DURING HEATING OF NICKEL COMPOSITE USING X-RAY DIFFRACTION ANALYSIS )

2018 ◽  
Vol 12 (1) ◽  
pp. 9-16
Author(s):  
Nur Vita Permatasari ◽  
Adji Kawigraha ◽  
Abdul Hapid ◽  
Nurhadi Wibowo
Keyword(s):  
Low Temperature ◽  
Diffraction Analysis ◽  
Mineral Content ◽  
Reduction Process ◽  
X Ray Diffraction ◽  
Composite Pellet ◽  
X Ray ◽  
Color Changes ◽  
Ore Processing ◽  
Mineral Changes

Logam nikel didapat dari proses pengolahan bijih nikel yang salah satunya adalah saprolit. Pada penelitian ini proses reduksi pelet komposit yang merupakan masa campuran bijih nikel serta batubara kadar rendah dan bahan tambahan dilakukan dalam tungku tabung. Proses reduksi dilakukan pada temperatur 450 °C, 700 °C serta 1100 °C selama 0 jam. Proses reduksi juga dilakukan pada temperatur yang lebih tinggi yaitu 1300 °C namun dengan pemanasan terlebih dahulu pada temperatur 700 °C dan ditahan pada 1 jam dan 2 jam. Produk pelet komposit dianalisis dengan metode difraksi sinar X untuk mengetahui kandungan mineralnya. Hasil menunjukkan bahwa pemanasan pelet komposit menyebabkan terjadinya perubahan warna dari warna coklat menjadi abu-abu. Pemanasan juga menyebabkan terjadinya perubahan komposisi mineral dari masing-masing pelet. Mineral-mineral yang terdapat dalam pelet komposit dan produknya adalah antigorit, klinoklor, kuarsa, enstatit, forsterit,gutit, hematit, magnetit, nikel dan besi. Pemanasan pelet pada temperatur rendah yang lebih lama akan menghasilkan jumlah logam besi yang lebih rendah. Nickel is obtained from saprolite through nickel ore processing. In this study, reduction of composite pellet has been done in a tube furnace. The pellet comsist of nickel ore, coal and additive. The reduction process carried out at 450˚C, 700˚C and 1100˚C for 0 hour. Moreover the reduction is also carried out at 700 °C during 1 and 2 hours followed by heating at 1300˚C for 2 and 1 hours. Reduction product was analyzed by X-Ray diffraction to determine the mineral content. The results indicate that the heating causing color changes from red brown to gray. Heating changes the mineral composition of the pellet. The minerals are antigorite, clinoclore, quartz, enstatite, forsterite, goethite, hematite, magnetite, nickel and iron. Heating the pellets at low temperature longer will produce lower iron.

A Discussion of the Measurement of Zn to ZnO Conversion in Aerosol Reactors

2009 ◽  
Author(s):  
Julia F. Haltiwanger ◽  
Luke J. Venstrom ◽  
Jane H. Davidson
Keyword(s):  
Quantitative Analysis ◽  
Low Temperature ◽  
Diffraction Analysis ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aerosol Reactors ◽  
Using Data ◽  
Hydrolysis Of ◽  
Zn Nanoparticles

One approach proposed for the exothermic step of the solar Zn/ZnO thermochemical water-splitting cycle is synthesis and hydrolysis of Zn nanoparticles in an aerosol reactor. To date the most common method to quantify the extent of conversion from Zn to ZnO is ex-situ X-ray diffraction analysis of particles collected on a filter placed at the exit of the reactor. The assumption inherent in this approach is that captured particles do not react on the filter because of its relatively low temperature. In the present study, we assess this assumption using data collected on hydrolysis of Zn nanoparticles at temperatures between 360 and 465 K and discuss methods of quantitative analysis via X-ray diffraction (XRD). Zn nanoparticles synthesized via condensation in an argon carrier gas are captured on a filter. Once the particles are collected, steam is introduced to the reactor at controlled partial pressure and temperature. The extent of reaction at the filter is characterized via calibrated XRD. At and below 380 K the reaction is negligible. At 465 K, the rate of conversion is slow at 0.007 ± 0.001%/min. In most cases, quantifying the extent of conversion from Zn to ZnO in the aerosol by ex-situ X-ray diffraction analysis of particles collected on the filter is an acceptable approach, though care should be taken in both the application of this method and in the quantitative analysis of the XRD data.

High resolution x‐ray diffraction analysis of annealed low‐temperature gallium arsenide

1992 ◽  
Vol 60 (21) ◽  
pp. 2642-2644 ◽  
Author(s):  
R. J. Matyi ◽  
M. R. Melloch ◽  
J. M. Woodall
Keyword(s):  
Gallium Arsenide ◽  
High Resolution ◽  
Low Temperature ◽  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
X Ray

Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalyse von cis-(n-Bu4N)2[ReBr4(NCS)2 ], cis-(n-Bu4N)2[ReBr4(NCSe)2] und cis-(n-Bu4N)2[ReBr4(NCS)(NCSe)] / Crystal Structures, Vibrational Spectra and Normal Coordinate Analyses of cis-(n-Bu4N)2[ReBr4(NCS)2], cis-(n-Bu4N)2[ReBr4(NCSe)2,] and cis -(n -Bu4N)2[ReBr4(NCS)(NCSe)]

2000 ◽  
Vol 55 (2) ◽  
pp. 178-184 ◽  
Author(s):  
L. Homolya ◽  
W. Preetz
Keyword(s):  
Low Temperature ◽  
Diffraction Analysis ◽  
Crystal Structures ◽  
Vibrational Spectra ◽  
X Ray Diffraction ◽  
Normal Coordinate ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Ir And Raman

The crystal structures of cis-(n-Bu4N)2[ReBr4(NCS)2] (1) (triclinic, space group P1̄, a = 11.475(6), b = 20.096(16), c = 22.144(11) Å, α = 110.56(6), β = 92.97(5), γ = 99.77(7)°, Z = 4), cis-(n-Bu4N)2[ReBr4(NCS)2] (2) (triclinic, space group P1̄, a = 11.527(3), b = 20.237(7), c = 22.07(2) Å, α = 110.05(4), β = 93.86(6), γ = 99.49(4)°, Z = 4) and cis-{n- Bu4N)2[ReBr4(NCS)(NCSe)] (3) (triclinic, space group P1̄, a = 11.488(2), b = 20.164(6), c = 22.158(5) Å, α = 110.44(2), β = 93.34(2), γ = 99.626(18)°. Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on these molecular parameters the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.70 (1), 1.70 (2) and 1.72 (3), fd(ReBr) = 1.36 (1), 1.30 (2) and 1.36 mdyn/Å (3).

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