Probing Plasticity Mechanisms in Low Melting Temperature Metallic Nanostructures Using Synchrotron X-Ray Microdiffraction

Temperature, thermal history, and dynamics of Earth rely critically on the knowledge of the melting temperature of iron at the pressure conditions of the inner core boundary (ICB) where the geotherm crosses the melting curve. The literature on this subject is overwhelming, and no consensus has been reached, with a very large disagreement of the order of 2,000 K for the ICB temperature. Here we report new data on the melting temperature of iron in a laser-heated diamond anvil cell to 103 GPa obtained by X-ray absorption spectroscopy, a technique rarely used at such conditions. The modifications of the onset of the absorption spectra are used as a reliable melting criterion regardless of the solid phase from which the solid to liquid transition takes place. Our results show a melting temperature of iron in agreement with most previous studies up to 100 GPa, namely of 3,090 K at 103 GPa.

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Synthese, Struktur und thermisches Verhalten von Thiophosphorsäuretriamid SP(NH2)3 [1] / Synthesis, Structure, and Thermal Behaviour of Phosphorothionic Triamide SP(ΝΗ2)3 [1]

Zeitschrift für Naturforschung B ◽

10.1515/znb-1989-0814 ◽

1989 ◽

Vol 44 (8) ◽

pp. 942-945 ◽

Cited By ~ 11

Author(s):

Wolfgang Schnick

Keyword(s):

Crystal Structure ◽

Hydrogen Bonding ◽

Thermal Properties ◽

Single Crystal ◽

Melting Temperature ◽

Intermolecular Hydrogen Bonding ◽

X Ray ◽

Hydrogen Bonding Interactions ◽

Ray Methods ◽

Single Bonds

Phosphorothionic triamide SP(NH2)3 is obtained by slow addition of SPCl3 dissolved in dry CH2Cl2 to a satured solution of NH3 in CH2Cl2 at —50°C. Ammonium chloride is removed from the resulting precipitate by treatment with HNEt2 followed by extraction with CH2Cl2. Coarse crystalline SP(NH2)3 is obtained after recrystallization from dry methanol. The crystal structure of SP(NH2)3 has been determined by single crystal X-ray methods (Pbca; a = 922.3(1), b = 953.8(1), c = 1058.4(2) pm, Z = 8). In the crystals the molecules show non-crystallographic point symmetry C8. The P—S bond (195.4(1) pm) is slightly longer than in SPCl3. From P—N bond lengths of about 166 pm a significant electrostatic strengthening of the P—N single bonds is assumed. Weak intermolecular hydrogen bonding interactions (N —H · · · N ≥ 329.5 pm; N — H · · · S ≥ 348.3 pm) are observed.Investigation of thermal properties shows a melting temperature of 115°C for SP(NH2)3. According to combined DTA/TG and MS investigations above this temperature the compound decomposes by evolution of H2S and NH3 to yield amorphous phosphorus(V)nitride.

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Spinel solid solutions in the systems MgAl2O4–ZnAl2O4 and MgAl2O4–Mg2TiO4

Journal of Materials Research ◽

10.1557/jmr.1997.0343 ◽

1997 ◽

Vol 12 (10) ◽

pp. 2584-2588 ◽

Cited By ~ 42

Author(s):

M. A. Petrova ◽

G. A. Mikirticheva ◽

A. S. Novikova ◽

V. F. Popova

Keyword(s):

Solid Solution ◽

Phase Diagrams ◽

Melting Temperature ◽

Solid Solutions ◽

Spinel Structure ◽

Room Temperature ◽

Binary Systems ◽

Continuous Series ◽

X Ray ◽

Spinel Solid Solutions

Phase relations in two binary systems MgAl2O4–ZnAl2O4 and MgAl2O4–Mg2TiO4 have been studied and phase diagrams for them have been constructed. Based on the data of x-ray phase and crystal-optical analyses, the formation of a continuous series of solid solutions with spinel structure between the terminal members of the systems studied has been established. In the MgAl2O4–ZnAl2O4 system the solid solution is stable in the range from room temperature to melting temperature. In the MgAl2O4–Mg2TiO4 system the solid solution decomposes below 1380 °C, yielding the formation of limited regions of homogeneity on the basis of MgAlM2O4 and Mg2+2δ Ti1–δO4. Decomposition of the solid solution is accompanied by crystallization of MgTiO3.

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Preparation and Characterization of V-Type Amylose-Hexanol Complex

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.422.641 ◽

2011 ◽

Vol 422 ◽

pp. 641-645 ◽

Cited By ~ 1

Author(s):

Liu Zhi Yang ◽

Xin Xin Xiao ◽

Miao Miao Zheng ◽

Yin Long Xu ◽

Yan Qi Liu

Keyword(s):

Melting Temperature ◽

Particle Diameter ◽

X Ray Diffraction ◽

X Ray ◽

Solvent Method ◽

Aqueous Solvent ◽

Alcohol Solvent ◽

Alcohol Solvents ◽

Scanning Electron

In this paper, B-type microcrystalline starch made a combination with hexanol in the case of water and alcohol as solvent respectively, V-type amylose-hexanol complexes were prepared. Obtained V-type amylose-hexanol complexes were characterized with scanning electron microscopy, X-ray diffraction, differential scanning calorimete. The results showed that using the preparation of water and alcohol solvents, obtained V-type amylose-hexanol complexes were hydrates and anhydrous crystal respectively. Hydrate crystal’s particles adhesion were serious, the particle diameter of anhydrous crystalline was 0.5~1μm, the crystallinity of both were above 70%. The V-type complexes prepared by aqueous solvent method and alcohol solvent method had almost the same melting temperature, the melting temperature of hydrates and anhydrous forms crystal were 70.7°C and 69.36°C.

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Effect of Ce2O3 and CaO/Al2O3 on the Phase, Melting Temperature and Viscosity of CaO-Al2O3-10 Mass% SiO2 Based Slags

High Temperature Materials and Processes ◽

10.1515/htmp-2013-0025 ◽

2014 ◽

Vol 33 (1) ◽

pp. 77-84 ◽

Cited By ~ 1

Author(s):

Chengchuan Wu ◽

Guoguang Cheng ◽

Hu Long

Keyword(s):

Melting Temperature ◽

Slag Composition ◽

Slag System ◽

Refining Process ◽

Phase Identification ◽

X Ray Diffraction ◽

Green Color ◽

X Ray ◽

Point Detector ◽

O Phase

AbstractThe melting temperature and viscosity of CaO-Al2O3-10 mass% SiO2 based slag system with various concentrations of Ce2O3 have been studied using the melting point detector and the rotating crucible viscometer. And X-ray diffraction analysis has been used for phase identification. The results show that cerium is stable in Ce3+ state existing mainly as CeAlO3 and Ce4.67(SiO4)3O phase in slags and CeAlO3 phase appears in green color. The melting temperature gently decreases with Ce2O3 additions in 1.57 of CaO/Al2O3. Moreover, the melting temperature increases first and then decreases with the increasing of CaO/Al2O3 from 1.17 to 1.52 at 4.47 mass% Ce2O3. In addition, at 1.57 of CaO/Al2O3, the viscosity increases at the beginning and then decreases with the increasing Ce2O3 content from 4.39 to 11.48 mass%. Furthermore, at 4.47 mass% Ce2O3, the viscosity decreases at the first and then increases with the increasing CaO/Al2O3 from 1.17 to 1.52. Meanwhile, from the slopes of the Arrhenius relationship for viscosity, the activation energy range of viscous flow is from 179.07 to 433.70 kJ/mol. On the basis of these results, slag composition of 45.64 mass% CaO-39.02 mass% Al2O3-10.73 mass% SiO2-3.83 mass% Ce2O3 is melting temperature of 1361 °C and viscosity of 0.398 Pa·s (1500 °C), which has superiority and is more suitable for the actual refining process.

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Investigation on the Preparation Processes of Cu-Bi Master Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.841 ◽

2011 ◽

Vol 335-336 ◽

pp. 841-844 ◽

Cited By ~ 2

Author(s):

Li Na Zhang ◽

Bai Xiong Liu

Keyword(s):

Electron Microscopy ◽

Melting Temperature ◽

Master Alloy ◽

Holding Time ◽

Chemical Compositions ◽

X Ray Diffraction ◽

X Ray ◽

Two Phases ◽

Fluorescence Analyzer ◽

Scanning Electron

The Microstructure of Cu-Bi master alloy with different melt processes, such as different melting temperature and holding time, was observed by PHILIPS-XL30 scanning electron microscopy (SEM); phase analysis was conducted by Miniflex X-ray diffraction(XRD); Magix(PW2424) X-ray fluorescence analyzer(XRF) was used to analyze chemical compositions of Cu-Bi master alloy. The results show that there are Cu and Bi two phases in the Cu-Bi master alloy; The yielding rate of bismuth decreases with the rising melting temperature. It decreases slowly between 1100 °C to 1150 °C,while it decreases rapidly between 1150 °C to 1200 °C.The bismuth particles in the Cu-Bi master alloy prepared at 1100 °C are much larger than those prepared at 1150 °C,while the size of bismuth particles change little from 1150 °C to 1200 °C. So the better melting temperature of preparing Cu-Bi master alloy is 1150 °C.The yielding rate of bismuth decreases with the holding time increasing. But when the holding time is too short, there are large bismuth particles in Cu-Bi alloy .So the better holding time is 120s.

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Real-Time Investigation of Solid and Liquid State Reactions In Au-Sn/Cu System

MRS Proceedings ◽

10.1557/proc-167-315 ◽

1989 ◽

Vol 167 ◽

Author(s):

Seyong Oh ◽

Igor Y. Khandros ◽

Janet L. Poetzinger

Keyword(s):

Real Time ◽

Melting Temperature ◽

Liquid State ◽

Eutectic Temperature ◽

Phase Changes ◽

X Ray ◽

Analysis Technique ◽

In Situ Investigation

AbstractA real-time x-ray analysis technique has been developed and employed for in-situ investigation of solid and liquid state reactions in Au-Sn/Cu system as a function of temperature. Typically, 1 μm eutectic Au-Sn films were deposited on 1.5 μm Cu layers on Si wafers. Phase changes in Au-Sn films on Cu from ambient to above the eutectic temperature have been investigated. Cu diffusion into Au-Sn film above 250 °C resulted in a ternary Au-Sn-Cu compound and raised the melting temperature of the structure to about 325 °C. This affects joining characteristics of the Au-Sn metallization.

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Phase relationships in the system Si3N4–SiO2–Yb2O3

Journal of Materials Research ◽

10.1557/jmr.1995.0240 ◽

1995 ◽

Vol 10 (2) ◽

pp. 240-242 ◽

Cited By ~ 55

Author(s):

Toshiyuki Nishimura ◽

Mamoru Mitomo

Keyword(s):

Melting Temperature ◽

Silicon Oxynitride ◽

High Melting ◽

Powder Diffraction Data ◽

Intergranular Phase ◽

X Ray ◽

High Melting Temperature ◽

Nitride Ceramics ◽

Unit Cells ◽

Phase Relationships

Phase relationships in the system Si3N4−SiO2−Yb2O3 have been investigated at 1750 °C and compared with those in the system Si3N4−SiO2−Y2O3. Two types of ytterbium silicon oxynitride, Yb2Si3O3N4 (tetragonal) and Yb4Si2O7N2 (monoclinic), were confirmed to exist. The x-ray powder diffraction data of two compounds were indexed based on the space group and unit cells. Melting temperature of Yb4Si2O7N2 was determined as 1870 °C. Yb4Si2O7N2 is a better intergranular phase of silicon nitride ceramics for its high melting temperature.

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Nature of Stark Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3542857 ◽

1955 ◽

Vol 28 (4) ◽

pp. 1007-1020 ◽

Cited By ~ 1

Author(s):

Donald E. Roberts ◽

Leo Mandelkern

Keyword(s):

Natural Rubber ◽

Melting Temperature ◽

Melting Behavior ◽

X Ray Diffraction ◽

Equilibrium Melting Temperature ◽

X Ray ◽

Melting Temperatures ◽

Controlled Conditions ◽

Previous Assignment ◽

Diffraction Patterns

Abstract The melting behavior and x-ray diffraction patterns of four different samples of stark rubber have been investigated. The melting temperatures, 39° to 45.5° C, are substantially higher than that observed for natural rubber crystallized by cooling. The x-ray diffraction patterns indicate that the crystallites in stark rubber are oriented. This observation can explain the higher melting temperatures. Thus, the previous assignment of an equilibrium melting temperature, 28° (±1°) C, to unoriented crystalline natural rubber is shown to be appropriate. Several different methods that have been used successfully in preparing stark rubber under controlled conditions in the laboratory are outlined.

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