Application of micro X-ray diffraction to investigate the reaction products formed by the alkali–silica reaction in concrete structures

The aim of this research is to investigate the effect of LiNO3 on the alkali–silica reaction (ASR) expansion of reactive sandstone and the mechanism through which this occurs. This paper presents the results from tests carried out on rock prisms and concrete microbars prepared by sandstone and LiNO3. The findings show that LiNO3 does not decrease the expansion of these samples unless the molar ratio of [Li]/[Na + K] exceeds 1.66, and the expansion is greatly increased when its concentration is below this critical concentration. The expansion stress test proves that Li2SiO3 is obviously expansive. X-ray diffraction (XRD) and scanning electron microscope (SEM) results indicate that LiNO3 reacts with the microcrystalline quartz inside sandstone, inhibiting the formation of ASR gel, and the formation of Li2SiO3 causes larger expansion. A high concentration of LiNO3 might inhibit the ASR reaction in the early stages, and the formation of Li2SiO3 causes expansion and cracks in concrete after a long period of time.

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On the Reaction of ortho-Diphenoquinone Valence Isomers with Primary and Secondary Amines. X-Ray Structure Analysis of a 2,3-Dihydro-1H-azepinone and its Photochemical and Oxidative Conversion Products

Australian Journal of Chemistry ◽

10.1071/ch9791931 ◽

1979 ◽

Vol 32 (9) ◽

pp. 1931 ◽

Cited By ~ 1

Author(s):

H Becker ◽

K Gustafsson ◽

CL Raston ◽

AH White

Keyword(s):

Single Crystal ◽

Secondary Amines ◽

Reaction Products ◽

Oxidative Conversion ◽

X Ray Diffraction ◽

X Ray ◽

Primary And Secondary Amines ◽

Diffraction Structure ◽

Structure Determinations ◽

Photochemical Isomerization

Single-crystal X-ray diffraction structure determinations are reported for three reaction products and photoisomers formed from reactions between an o-diphenoquinone valence isomer and primary and secondary amines, namely: 3,5-di-t-butyl-7-(3,5-di-t-butyl-2-hydroxyphenyl)-1-methyl-2,3-dihydro-1H-azepin-2-one (8; R1 = R2 = But, R3 = Me), its photochemical isomerization product 4,6-di-t-butyl-1-(3,5-di-t-butyl-2-hydroxyphenyl)-2-methyl-2-azabicyclo[3,2,0]hept-6-en-3-one (9; R1 = R2 = But, R3 = Me) and 4',5,7-tri-t-butyl-3'-(2,2-dimethylpropionyl)-1'-methylspiro[benzofuran-3(2H)-2'- pyrrolidinel-2,5'-dione (12; R1 = R2 = But, R3 = Me).

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Microstructure Characterization of the Reaction Interface between CBN Grain and Titanium-Deposited Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.166 ◽

2012 ◽

Vol 538-541 ◽

pp. 166-171

Author(s):

Wen Feng Ding ◽

Yang Min Liang ◽

Jian He ◽

Li Tang ◽

Jie Yu ◽

...

Keyword(s):

Heating Temperature ◽

Cubic Boron Nitride ◽

High Vacuum ◽

Reaction Products ◽

X Ray Diffraction ◽

X Ray ◽

Energy Dispersion Spectrometer ◽

Heat Treated ◽

Deposited Film

Cubic boron nitride (CBN) abrasive grains with surface titanium-deposited film were heat-treated during 550-950°C for 60 min under high vacuum circumstance. Detailed interfacial compounds analysis by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion spectrometer (EDS), differential thermal analysis (DTA) indicates that the interfacial reactions are much dependent on the heating temperature to some extents, and the reaction products, TiN, TiB2 and TiB chiefly form the network structure. In particular, at 950°C the transition layers with excellent performance, CBN/TiB2/TiB/(TiB+TiN)/TiN/CBN, is realized.

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Application of Gandolfi X-Ray Diffraction to the Characterization of Reaction Products from the Alteration of Simulated Nuclear Wastes

Advances in X-ray Analysis ◽

10.1154/s0376030800007424 ◽

1980 ◽

Vol 24 ◽

pp. 265-269 ◽

Cited By ~ 1

Author(s):

C. A. F. Anderson ◽

M. E. Zolensky ◽

D. K. Smith ◽

W. P. Freeborn ◽

B. E. Scheetz

Keyword(s):

Powder Diffraction ◽

Individual Particle ◽

Nuclear Wastes ◽

Reaction Products ◽

X Ray Diffraction ◽

X Ray ◽

The Individual ◽

Individual Grains ◽

Phase Characterization

AbstractAccurate phase characterization of the alteration products of rad-waste requires the separation and identification of scattered individual grains from among the bulk product. These grains are typically 5 to 100 μm in size. Bulk x-ray powder diffraction will normally not detect these minor phases, and even if the phase can be detected, it often may not be identifiable. The use of the Gandolfi technique with the individual particle not only facilitates the identification, but also allows the assignment of the identification to the specific grain.

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S4N4 und seine Derivate: Isolierung und Struktur von S4N4H+[SnCl5(H2O)]– und (S3N2NH2+)2[SnCl6]2– / S4N4 and its Derivatives: Isolation and Structure of S4N4H+[SnCl5(H2O)]- and (S3N2NH2+)2[SnCl6]2-

Zeitschrift für Naturforschung B ◽

10.1515/znb-1986-0509 ◽

1986 ◽

Vol 41 (5) ◽

pp. 581-586 ◽

Cited By ~ 4

Author(s):

Konrad Holl ◽

Ulf Thewalt

Keyword(s):

Acetic Acid ◽

Molecular Structures ◽

Reaction Products ◽

X Ray Diffraction ◽

X Ray ◽

Crystal And Molecular Structures

Among the reaction products of S4N4 with SnCl4 in chloroform, that contains acetic acid and small amounts of water, there are two salts S4N4H+[SnCl5(H2O)]- (A) and (S3N2NH2+)2[SnCl6]2- (B), both containing protonated SnNm units. The crystal and molecular structures of A and B have been determined by X-ray diffraction. A: monoclinic, P21/c, a = 9.084(2), b - 23.758(4), c = 6.587(1) Å , β = 101.86(3)°, Dc = 2.383 g·cm-3 and Z = 4. B: monoclinic, P21/n, a = 9.882(3), b = 12.873(4), c = 6.807(2) Å , β = 93.77(5)°, Dc = 2.352 g·cm-3 and Z = 2. The structures of the cations in both compounds agree well with those found of other salts containing these cations.

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Photoreaktionen von Dekacarbonyldirhenium mit Allen und unverzweigten Allenderivaten / Photoreactions of Decacarbonyldirhenium with Allene and Unbranched Derivatives of Allene

Zeitschrift für Naturforschung B ◽

10.1515/znb-1995-0430 ◽

1995 ◽

Vol 50 (4) ◽

pp. 649-660 ◽

Cited By ~ 5

Author(s):

Cornelius G. Kreiter ◽

Wolfgang Michels ◽

Gerhard Heeb

Keyword(s):

Nmr Spectra ◽

Crystal And Molecular Structure ◽

Reaction Products ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Oxidative Rearrangement ◽

Dirhenium Complexes ◽

Derivatives Of ◽

By Products

Decacarbonyldirhenium (1) reacts upon UV irradiation with allene (2), 1,2-butadiene (3) and 2,3-pentadiene (4) preferentially by CO substitution and oxidative rearrangement to the corresponding enneacarbonyl-μ-η1:3-endiyl-dirhenium complexes 5, 9, and 15 and to the octacarbonyl-μ-η2:2-allene-dirhenium complexes 6, the stereoisomers 10, 11, and 16. At elevated temperature 5, 9, and 15 loose CO and yield by a reductive rearrangement also the complexes 6, 10, 11, and 16. In addition to these main products, depending upon the allene derivative used, various by-products are obtained.By-products of the reaction o f 1 with 2 are octacarbonyl-μ-η3:3-(2,3-dimethylene-buta-1,4- diyl)dirhenium (7) and μ-η2:2-allene-hexacarbonyl-μ-η1:3-1-propene-1,3-diyl-dirheniurn (8). The photo reaction of 1 with 3 yields, in addition to 9-11, tetracarbonyl-η3-(E-5-ethylidene- 4-methyl-2-cyclopenten-1-yl)rhenium (12) and tetracarbonyl-η3-(Z-5-ethyliden-4- methyl-2-cyclopenten-1-yl)rhenium (13) as a mixture of isomers. 1 and 4 form the by-products tetracarbonyl-η3-(EZ-3-penten-2-yl)rhenium (17), tetracarbonyl-η3-(EE-3-penten-2-yl)rhenium (18) and heptacarbonyl-μ-η1:2:1:2-(4,5-dimethyl-2,6-octadiene-3,6-diyl)dirhenium (19) with an unusually bridging and chelating ligand. The constitutions of the reaction products have been concluded from the IR and 1H NMR spectra. For 19 the crystal and molecular structure has been determined by X-ray diffraction analysis.

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The Dehydrogenation Mechanism and Reversibility of LiBH4 Doped by Active Al Derived from AlH3

Metals ◽

10.3390/met9050559 ◽

2019 ◽

Vol 9 (5) ◽

pp. 559 ◽

Cited By ~ 2

Author(s):

Qing He ◽

Dongdong Zhu ◽

Xiaocheng Wu ◽

Duo Dong ◽

Xiaoying Jiang ◽

...

Keyword(s):

Reaction Products ◽

X Ray Diffraction ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Scanning Calorimetry ◽

Mass Spectral Analysis ◽

X Ray ◽

Mass Spectral ◽

Al Composite ◽

Dehydrogenation Mechanism

A detailed analysis of the dehydrogenation mechanism and reversibility of LiBH4 doped by as-derived Al (denoted Al*) from AlH3 was performed by thermogravimetry (TG), differential scanning calorimetry (DSC), mass spectral analysis (MS), powder X-ray diffraction (XRD), scanning electronic microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results show that the dehydrogenation of LiBH4/Al* is a five-step reaction: (1) LiBH4 + Al → LiH + AlB2 + “Li-Al-B-H” + B2H6 + H2; (2) the decomposition of “Li-Al-B-H” compounds liberating H2; (3) 2LiBH4 + Al → 2LiH + AlB2 + 3H2; (4) LiBH4 → LiH + B + 3/2H2; and (5) LiH + Al → LiAl + 1/2H2. Furthermore, the reversibility of the LiBH4/Al* composite is based on the following reaction: LiH + LiAl + AlB2 + 7/2H2 ↔ 2LiBH4 + 2Al. The extent of the dehydrogenation reaction between LiBH4 and Al* greatly depends on the precipitation and growth of reaction products (LiH, AlB2, and LiAl) on the surface of Al*. A passivation shell formed by these products on the Al* is the kinetic barrier to the dehydrogenation of the LiBH4/Al* composite.

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Chemistry of Polyhalogenated Nitrobutadienes, Part 9: Acyclic and Heterocyclic Nitroenamines and Nitroimines from 2-Nitroperchlorobuta-1,3-diene

Zeitschrift für Naturforschung B ◽

10.1515/znb-2010-0710 ◽

2010 ◽

Vol 65 (7) ◽

pp. 843-860 ◽

Cited By ~ 9

Author(s):

Viktor A. Zapol’skii ◽

Jan C. Namyslo ◽

Mimoza Gjikaj ◽

Dieter E. Kaufmann

Keyword(s):

Single Crystal ◽

Diffraction Analysis ◽

Ring Closure ◽

Reaction Products ◽

X Ray Diffraction ◽

Substitution Pattern ◽

X Ray

Various amino, diamino, aminothio, or benzotriazolo compounds derived from the exceedingly versatile 2-nitroperchlorobutadiene (1) gave structurally interesting and physiologically promising nitro-enamines, -imines, -amidines, and hydrazines as well as ring closure reaction products, e. g. pyrimidines and pyrazoles. Most of these reactions turned out to be highly selective with good to very good yields. The structure of the pyrazole precursor (E,E)-1-(benzotriazol-1-yl)-4,4-dichloro-3- (4-ethoxyphenylamino)-1-(4-ethoxyphenylimino)-2-nitrobut-2-ene (30), due to its exceptional substitution pattern, was evidenced by single-crystal X-ray diffraction analysis.

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Investment Casting of Titanium Matrix Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.2551 ◽

2005 ◽

Vol 475-479 ◽

pp. 2551-2554 ◽

Cited By ~ 1

Author(s):

Si Young Sung ◽

Keun Chang Park ◽

Myoung Gyun Kim ◽

Young Jig Kim

Keyword(s):

In Situ Synthesis ◽

Matrix Composites ◽

Reaction Products ◽

X Ray Diffraction ◽

Titanium Matrix ◽

Titanium Matrix Composites ◽

X Ray ◽

Conventional Casting ◽

Electron Probe Micro Analyzer

The aim of the present work is to investigate the possibility of in-situ synthesis and net-shape of the titanium matrix composites (TMCs) using a casting route. From the scanning electron microscopy (SEM), electron probe micro-analyzer (EPMA), X-ray diffraction (XRD) and thermodynamic calculations, the spherical TiC and needle like TiB reinforced hybrid TMCs could be obtained by the conventional casting route between titanium and B4C. No melts-mold reaction could be possible between (TiC+TiB) hybrid TMCs and the SKKU mold, since the mold is composed of interstitial and substitutional reaction products. Not only the sound in-situ synthesis but also the economic net-shape of TMCs could be possible by conventional casting route.

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