Successful melting and density measurements of Cu and Ag single crystals with an electrostatic levitation (ESL) system

The sesquioxide Lu2O3 single crystal, with high quality and optical homogeneity, has been grown controllably with an oriented seed by EFG method for the first time. The EFG method is promoted to an extremely high temperature of 2450 °C.

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Evaluation of Multicomponent Nickel Base LI2 and Other Intermetallic Alloys as High Temperature Structural Materials

MRS Proceedings ◽

10.1557/proc-81-411 ◽

1986 ◽

Vol 81 ◽

Cited By ~ 6

Author(s):

D. M. Shah ◽

D. N. Duhl

Keyword(s):

High Temperature ◽

Single Crystal ◽

Single Crystals ◽

Impact Resistance ◽

High Strength ◽

Structural Materials ◽

Nickel Base Superalloy ◽

Intermetallic Alloys ◽

Nickel Base ◽

Base Superalloy

AbstractMulticomponent nickel base intermetallics with the L12 structure were evaluated as high temperature structural materials. The compounds were based on the γ' composition of PWA 1480, a high strength single crystal nickel base superalloy. The best balance of properties in the compound was achieved with <111> oriented single crystals but no significant advantage could be demonstrated over the precipitation hardened superalloys. Insufficient impact resistance was a major deficiency of the L12 compounds. Other nickel base intermetallics were also evaluated but showed little advantage over superalloys.

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Refinement of the layered titanosilicate AM-1 from single-crystal X-ray diffraction data

Acta Crystallographica Section E Structure Reports Online ◽

10.1107/s160053680704812x ◽

2007 ◽

Vol 63 (11) ◽

pp. i186-i186 ◽

Cited By ~ 8

Author(s):

Stanislav Ferdov ◽

Uwe Kolitsch ◽

Christian Lengauer ◽

Ekkehart Tillmanns ◽

Zhi Lin ◽

...

Keyword(s):

Raman Spectroscopy ◽

Hydrogen Bonding ◽

Single Crystal ◽

Single Crystals ◽

Diffraction Data ◽

X Ray Diffraction ◽

X Ray ◽

First Time ◽

Ir And Raman ◽

Bonding Scheme

The structure of the layered noncentrosymmetric titanosilicate AM-1 (also known as JDF-L1, disodium titanium tetrasilicate dihydrate), Na4Ti2Si8O22·4H2O, grown as small single crystals without the use of organics, has been refined from single-crystal X-ray diffraction data. The H atom has been located for the first time, and the hydrogen-bonding scheme is also characterized by IR and Raman spectroscopy. All atoms are in general positions except for the Na, the Ti, one Ti-bound O, one Si-bound O and the water O atoms (site symmetries 2, 4, 4, 2 and 2, respectively).

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Properties and growth of large single crystals of one-dimensional organic lead iodine perovskite

CrystEngComm ◽

10.1039/d0ce01104e ◽

2020 ◽

Vol 22 (42) ◽

pp. 7090-7094 ◽

Cited By ~ 1

Author(s):

Yiming Wang ◽

Yanliang Liu ◽

Yizhang Wu ◽

Junjie Jiang ◽

Chunlin Liu ◽

...

Keyword(s):

Single Crystal ◽

Single Crystals ◽

One Dimensional ◽

Organic Lead ◽

First Time

Here, we demonstrate for the first time the growth of 2 mm × 4 mm × 8 mm sized single crystal one dimensional organic lead iodine perovskite – DMAPbI3 ((CH3)2NH2PbI3).

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Experimental Study of the High Temperature Mechanical Behaviors of TLP Bonding of Two Ni-Base Single Crystals

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.1489 ◽

2005 ◽

Vol 297-300 ◽

pp. 1489-1494 ◽

Cited By ~ 3

Author(s):

T. Li ◽

Qing Yuan Wang ◽

Ai Qin Wang ◽

Z.X. Wen ◽

Zhu Feng Yue

Keyword(s):

Experimental Study ◽

High Temperature ◽

Single Crystal ◽

Single Crystals ◽

Base Material ◽

Static Strength ◽

Loading Conditions ◽

Mechanical Behaviors ◽

Tensile Direction ◽

Tlp Bonding

In this paper, the mechanical behavior of Ni-base single crystals joint created by TLP bonding is presented. Experimental study has been performed on the TLP single crystal under loading conditions of static uniaxial tension, creep and Three-points-bending (T-P-B) at temperature of 850 °C. Specimens made of the base material, Ni-base single crystal specimens without bonding, were also tested under the same loading conditions. The mechanical behaviors of TLP single crystal is compared to the behaviors of base material. It was found that the static strength of the TLP specimens with the boundary normal to the tensile direction was 63% of the strength of the base material. The creep strength and the fracture ductile strength was more than 57% and 55% of that of the single crystal base material, respectively. The macro and micro graphs of fracture surfaces of specimens indicated that the fracture modes of the samples were brittle fracture.

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Adjustable Positive-Negative Signal in Self-Driven Photodetector based on Cubic CH3NH3PbI3 Large Single Crystal

10.26434/chemrxiv.14248607 ◽

2021 ◽

Author(s):

Xuewei Fu ◽

Yunying Wang ◽

Huawei Zhou ◽

Yan Chen ◽

Chen Wang ◽

...

Keyword(s):

Response Time ◽

Single Crystal ◽

Band Gap ◽

Single Crystals ◽

Photocurrent Density ◽

Large Single Crystal ◽

Orientation Disorder ◽

Octahedral Cavity ◽

First Time ◽

Negative Signal

In this study, for the first time, self-driven photodetector based on cubic CH3NH3PbI3 large single crystal (C-MAPbI3 LSC) with adjustable positive-negative signal is fabricated. The preparation of MAPbI3 large single crystal (MAPbI3 LSC) is realized by the method of growth-drop-growth (GDG). The band gap of MAPbI3 single crystals with Pm-3m (221) space group (6.134×6.134×6.134 Å, 90.00 x 90.00 x 90.00) is 1.58 eV. CH3NH3+ cation is orientation-disorder within the perovskite cubo-octahedral cavity. The photocurrent density at 803 nm of the C-MAPbI3 LSC photodetector under different bias voltages is the highest under different wavelength. The responsivities (R), response time, external quantum efficiencies (EQE) and the detectivity (D) for C-MAPbI3 LSC photodetector at 803 nm wavelength with 1 W m-2, respectively, is 508.7 µA/mW, 0.1338 ms, 79.6% and 8.64*1011 Jones. Notably, the C-MAPbI3 LSC photodetector can be self-driven under 0 V bias voltage, in particular, the positive and negative values of the photocurrent can be adjusted. The proposed mechanism of poling inducing built-in potential is explained adjustable positive-negative signal in self-driven photodetector based on cubic CH3NH3PbI3 large single crystal.

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Raman Spectroscopy and Single-Crystal High-Temperature Investigations of Bentorite, Ca6Cr2(SO4)3(OH)12·26H2O

Minerals ◽

10.3390/min10010038 ◽

2019 ◽

Vol 10 (1) ◽

pp. 38

Author(s):

Rafał Juroszek ◽

Biljana Krüger ◽

Irina Galuskina ◽

Hannes Krüger ◽

Martina Tribus ◽

...

Keyword(s):

Crystal Structure ◽

High Temperature ◽

Single Crystal ◽

Chemical Formula ◽

Crystal Chemical Formula ◽

Single Crystal Diffraction ◽

Bending Vibrations ◽

X Ray ◽

First Time

The crystal structure of bentorite, ideally Ca6Cr2(SO4)3(OH)12·26H2O, a Cr3+ analogue of ettringite, is for the first time investigated using X-ray single crystal diffraction. Bentorite crystals of suitable quality were found in the Arad Stone Quarry within the pyrometamorphic rock of the Hatrurim Complex (Mottled Zone). The preliminary semi-quantitative data on the bentorite composition obtained by SEM-EDS show that the average Cr/(Cr + Al) ratio of this sample is >0.8. Bentorite crystallizes in space group P31c, with a = b = 11.1927(5) Å, c =21.7121(10) Å, V = 2355.60(18) Å3, and Z = 2. The crystal structure is refined, including the hydrogen atom positions, to an agreement index R1 = 3.88%. The bentorite crystal chemical formula is Ca6(Cr1.613Al0.387)Σ2[(SO4)2.750(CO3)0.499]Σ3.249(OH)11.502·~25.75H2O. The Raman spectra of bentorite from two different localities exhibit the presence of the main stretching and bending vibrations related to the sulfate group at 983 cm−1 (ν1), 1109 cm−1 (ν3), 442 cm−1 (ν2), and 601 cm−1 (ν4). Moreover, the presence of bands assigned to the symmetric Cr(OH)63− stretching mode and hydroxyl deformation vibrations of Cr–OH units at ~540 cm−1 and ~757 cm−1, respectively, may be used to distinguish between ettringite and bentorite. In situ high temperature single crystal XRD experiments show that the decomposition of bentorite starts at ca. 45 °C and that a dehydroxylation product similar to metaettringite is formed.

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High Temperature Hardness of Bulk Single Crystal GaN

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300004488 ◽

2000 ◽

Vol 5 (S1) ◽

pp. 343-348

Author(s):

I. Yonenaga ◽

T. Hoshi ◽

A. Usui

Keyword(s):

High Temperature ◽

Single Crystal ◽

Room Temperature ◽

Applied Load ◽

Elevated Temperatures ◽

Mechanical Stability ◽

Bulk Single Crystal ◽

Indentation Method ◽

First Time ◽

High Mechanical Stability

The hardness of single crystal GaN (gallium nitride) at elevated temperature is measured for the first time and compared with other materials. A Vickers indentation method was used to determine the hardness of crack-free GaN samples under an applied load of 0.5N in the temperature range 20 - 1200°C. The hardness is 10.8 GPa at room temperature, which is comparable to that of Si. At elevated temperatures GaN shows higher hardness than Si and GaAs. A high mechanical stability for GaN at high temperature is deduced.

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Peculiarities of pseudogap in Y0.95Pr0.05Ba2Cu3O7−δ single crystals under pressure up to 1.7 GPa

Scientific Reports ◽

10.1038/s41598-019-55959-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

A. L. Solovjov ◽

L. V. Omelchenko ◽

E. V. Petrenko ◽

R. V. Vovk ◽

V. V. Khotkevych ◽

...

Keyword(s):

Critical Temperature ◽

Hydrostatic Pressure ◽

Single Crystal ◽

Single Crystals ◽

Temperature Interval ◽

Fluctuation Theory ◽

Structural Defects ◽

Fluctuation Conductivity ◽

First Time ◽

Effect Of Hydrostatic Pressure

AbstractThe effect of hydrostatic pressure up to P = 1.7 GPa on the fluctuation conductivity σ′(T) and pseudogap ∆*(T) in Y0.95Pr0.05Ba2Cu3O7−δ single crystal with critical temperature Тс = 85.2 K (at P = 0) was investigated. The application of pressure leads to the increase in Tc with dTc/dP = +1.82 K∙GPa−1 while the resistance decreases as dlnρ(100 K)/dP = −(10.5 ± 0.2) %∙GPa−1. Regardless of the pressure, in the temperature interval from Tc to T0 (~88 K at P = 0) the behaviour of σ′(T) is well described by the Aslamazov – Larkin (AL – 3D) fluctuation theory, and above the T0 by the Lawrence – Doniach theory (LD). The Maki-Thompson (MT – 2D) fluctuation contribution is not observed. This indicates the presence of structural defects in the sample induced by Pr. Here it is determined for the first time that when the pressure is applied to the Y1−xPrxBa2Cu3O7−δ single crystal, the pseudogap increases as dlnΔ*/dP = 0.17 GPa–1.

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Flame Technique for High Temperature Single Crystal Weissenberg Photography (1000-3000°C)

Advances in X-ray Analysis ◽

10.1154/s0376030800011228 ◽

1971 ◽

Vol 15 ◽

pp. 548-555

Author(s):

M. A. Viswamitra ◽

K. Jayalakshmi

Keyword(s):

High Temperature ◽

Single Crystal ◽

Single Crystals ◽

Water Cool ◽

X Ray ◽

Flame Heating ◽

Experimental Crystal

Oxy-acetylene flame heating has been employed with an ordinary Nonius Weissenberg camera for high-temperature single-crystal studies over the the range 1000-3000°C. The regulator blow pipe is mounted horizontally on the camera track and one end of the experimental crystal (1 cm long) is heated by the vertical flame issuing out of a 0.5 mm bore nozzle* A long slot cut at the top of the film-cassette allows the flame to escape out without touching the X-ray film. The film-cassette consists of two split-halves hinged on one side so that it can be opened and slipped over the screen tubes. This arrangement avoids the necessity for removing the flame each time a new film is mounted on the camera. The goniometer arcs can be positioned during high-temperature exposures, and there is no need to water-cool the cassette up to the highest temperature. The device has been used to take photographs of MgO single crystals at 2100°C. It permits a ready application to diffractometers based on Weissenberg geometry.

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