Radiation effects on room temperature epoxy adhesive molecular structure: Mechanical tests and correlation with calorimetric and outgassing analyses

1999 ◽  
Vol 38 (5-6) ◽  
pp. 623-633 ◽  
Author(s):  
F. S. Guarino ◽  
C. Hauviller ◽  
J. M. Kenny
Keyword(s):  
Molecular Structure ◽  
Radiation Effects ◽  
Room Temperature ◽  
Mechanical Tests ◽  
Epoxy Adhesive

Molecular Structure of[Pd6Cl12] in Single Crystals Chemically Grown at Room Temperature

1996 ◽  
Vol 35 (12) ◽  
pp. 1331-1333 ◽  
Author(s):  
Daniela Belli Dell'Amico ◽  
Fausto Calderazzo ◽  
Fabio Marchetti ◽  
Stefano Ramello
Keyword(s):  
Molecular Structure ◽  
Single Crystals ◽  
Room Temperature

scholarly journals Influence of molecular structure on helicoidal structure and NMR spectra of chiral liquid crystalline esters

2017 ◽  
Vol 66 (2) ◽  
pp. 25-35
Author(s):  
Anna Drzewicz ◽  
Marzena Tykarska ◽  
Mateusz Szala ◽  
Magdalena Żurowska
Keyword(s):  
Molecular Structure ◽  
Nmr Spectra ◽  
Liquid Crystalline ◽  
Room Temperature ◽  
Alkyl Chain ◽  
Light Reflection ◽  
13C Nmr Spectra ◽  
1H And 13C Nmr ◽  
Antiferroelectric Phase ◽  
Helicoidal Structure

Three-ring chiral liquid crystalline compounds, forming antiferroelectric phase, differing in the structure of alkyl chain and in the substitution of benzene ring by fluorine atoms were studied. The measurements of helical pitch, based on the selective light reflection phenomenon, were performed as well as 1H and 13C NMR spectra at room temperature were registered. The influence of molecular structure as well as the type of helicoidal structure on the chemical shift of signals coming from chiral center was observed. Keywords: liquid crystals, helicoidal structure, nuclear magnetic resonance, antiferroelectric phase

Synthesis, Crystal Structure and Antimicrobial Activity of Poly [bis-and#181;-3,5-dinitro-2-oxidobenzoato) (py) Cu II]

2020 ◽  
Vol 42 (6) ◽  
pp. 928-928
Author(s):  
Fouzia Chang Fouzia Chang ◽  
Najma Memon Najma Memon ◽  
Shahabuddin Memon Shahabuddin Memon ◽  
Muhammad Naeem Ahmed Muhammad Naeem Ahmed ◽  
Muhammad Nawaz Tahir Muhammad Nawaz Tahir ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Room Temperature ◽  
Central Metal Atom ◽  
Central Metal ◽  
Single Crystal Xrd ◽  
Monoclinic System ◽  
X Ray ◽  
Pyramidal Geometry ◽  
Square Pyramidal Geometry

A novel Poly [bis-and#181;-3,5-dinitro-2-oxidobenzoato) (py) Cu II]/(C12H7CuN3O7) was synthesized by a self assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P 2 1/c with lattice parameters of a = 10.2143, b = 5.1651 and c = 26.608, α = 90, β = 99.720, γ = 90, Z = 4, V = 1383.60 (18) and#197;3.Pore size depicted from single crystal XRD data was 47and#197;. The central metal atom Cu (II) is coordinated with oxygen of carboxylates group and nitrogen atom of pyridine. The coordination polyhedron posses square pyramidal geometry is manifested by the N— Cu—O angle of 90o. The structure is composed of monomeric coordination units with the central copper (II) ion is not occupying a centre of symmetry.

Active Belite Cement Clinker Produced with Mineral Waste

2012 ◽  
Vol 610-613 ◽  
pp. 2378-2385 ◽  
Author(s):  
Yan Jun Liu ◽  
Yong Chao Zheng
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
Mechanical Tests ◽  
Tricalcium Silicate ◽  
Dicalcium Silicate ◽  
Cement Industry ◽  
Cement Clinker ◽  
Strength Development ◽  
Belite Cement ◽  
Mineral Waste

This paper presents a laboratory study on active belite cement linker using mineral waste as one of the major raw meal components. The main chemical component of mineral waste employed in this study is silica (SiO2), around 70%. The raw meals were soaked in Muffle Furnace at 1350oC for 10 minutes and 20minutes respectively, then, cooled down to room temperature using air blower. Boron Oxide was used to stabilize high temperature phases of C2S. QXRD analysis indicates that active belite cement clinker has major mineral components consisting of Dicalcium Silicate (C2S), Ferrite (C2 (A0.48F1.52) O5) and trace amount of Tricalcium Silicate (C3S). Among them, Dicalcium silicate is over 85 percent, Ferrite around 10 percent and Tricalcium silicate less than 10 percent. Also, significant amount of high temperature polymorphic C2S was stabilized under room temperature. Among polymorphic belite phases, αH-C2S accounts for around 66% of cement clinker, and αL-C2S for about 22% of cement clinker. Scanning Eαlectronic Microscope (SEM) analysis also shows coαnsiderable round grains of C2S. TGA-DSC spectrum indicated there is no significant phase change while cement clinker was cooling down. Also, the mechanical tests on active belite cement show that active belite cement clinker has a slow strength development at early ages, but rapid strength gain over 70Mpa at 28 days. Thus, this active belite cement clinker demonstrates very promising prospect in sustainable cement industry development.

Synthesis and X -Ray Crystal Structure of the Heterobimetallic Complex [FeRh (μ-CO)(CO)3((μ-PBut2)((μ-Ph2PCH2PPh2)]

1997 ◽  
Vol 52 (7) ◽  
pp. 810-814 ◽  
Author(s):  
Hans-Christian Böttcher ◽  
Kurt Merzweiler ◽  
Clemens Bruhn
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Room Temperature ◽  
Metal Carbonyl ◽  
Homogeneous Catalyst ◽  
Catalyst Precursor ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Heterobimetallic Complex

Abstract The reaction of the phosphido-bridged metal carbonyl [FeRh(CO)6(μ-PBut2)] (1) with dppm [dppm = bis(diphenylphosphino)methane] leads to the heterobimetallic complex [FeRh(μ-CO)(CO)3(μ-PBut2)(μ-dppm)] (2) in good yields. The molecular structure of 2 was determined at room temperature [triclinic, space group P1̄, a = 9.509(6), b = 13.637(5), c = 14.926(8) Å, α = 81.38(4), β = 82.75(4), γ = 71.25(4)°]. The compound acts as a homogeneous catalyst precursor in the hydroformylation reaction of ethylene, but it decomposes during this process.

Room-temperature radiation effects in Al-doped Y-bar quartz

1994 ◽  
Vol 6 (24) ◽  
pp. 4457-4464 ◽  
Author(s):  
Xi-Qi Feng ◽  
T B Tang ◽  
Wei-Zhuo Zhong
Keyword(s):  
Radiation Effects ◽  
Room Temperature ◽  
Temperature Radiation

Mechanical Properties and Microstructure Development of Ultrafine-Grained Cu Processed by ECAP

2008 ◽  
Vol 584-586 ◽  
pp. 440-445 ◽  
Author(s):  
Miloš Janeček ◽  
Jakub Čížek ◽  
Milan Dopita ◽  
Robert Král ◽  
Ondřej Srba
Keyword(s):  
Room Temperature ◽  
Defect Density ◽  
Mechanical Tests ◽  
Microstructure Development ◽  
Vacancy Clusters ◽  
Ecap Pass ◽  
Angular Pressing ◽  
Ultrafine Grained ◽  
Positron Annihilation Spectrometry ◽  
The Mean

Technical purity Cu (99.95 wt%) polycrystals have been processed at room temperature by equal channel angular pressing. The results of mechanical tests and the microstructure characterization by various experimental techniques are presented. The yield stress as well as the strength were shown to increase with increasing strain and exceed the respective values of a coarsegrained material. The microstructure development and its fragmentation after ECAP was investigated by the TEM and EBSD. The proportion of high angle grain boundaries was found to increase with increasing strain reaching the value of 90% after 8 ECAP passes. Two kinds of defects were identified in ECAP specimens by positron annihilation spectrometry (PAS): (a) dislocations which represent the dominant kind of defects, and (b) small vacancy clusters (so called microvoids). The main increase of defect density was found to occur during the first ECAP pass. PAS analysis indicated that in the specimens subjected to one ECAP pass the mean dislocation density ρD and the concentration of microvoids cν exceeded the values of 1014 m-2 and 10-4 at.-1, respectively. After 4 passes, the number of defects becomes saturated and practically does not change with increasing strain.

Spaltung von S4N4 zu S2N2 bei Raumtemperatur: Darstellung und Struktur von S2N2 • 2AlBr3 / Cleavage of S4N4 to S2N2 at Room Tem perature: Preparation and Structure of S2N2 • 2AlBr3

1984 ◽  
Vol 39 (2) ◽  
pp. 145-148 ◽  
Author(s):  
Ulf Thewalt ◽  
Konrad Holl
Keyword(s):  
Molecular Structure ◽  
Room Temperature ◽  
Crystal And Molecular Structure ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bond Lengths

The compound S2N2 • 2AlBr3 has been prepared by reaction of S4N4 with AlBr3 in 1,2-dibromoethane at room temperature. Its crystal and molecular structure have been determined by X-ray diffraction; R = 0.068. Crystal data: monoclinic, P 21/n, a = 9.594(5), b = 9.975(4), c = 7.528(4) Å , β = 111.36(5)°. The S2N2 ring of the centrosymmetrical complex is bonded via its nitrogen atoms to two AlBr3 units thus completing coordination tetrahedra around the Al atoms. Bond distances and angles within the S2N2 ring are d(S-N) = 1.629(13) and 1.651(13) Å, ∢ (S-N-S) = 95.8, and ∢ (N-S-N) - 84.2°. Whereas the S-N bond lengths agree closely with those of free S2N2, the angle at N is enlarged by ca. 5° and the angle at S is decreased by ca. 5°. The sulfur atoms form two close S···Br contacts of length 3.149 (intramolecular) and 3.193 (intermolecular) Å , respectively. The intermolecular attractive nonbonded S···Br interactions tie the complexes together in a way that leads to infinite chains which run parallel to the crystallographic z axis

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