Increasing the structural boundary of quasiracemate formation: 4-substituted naphthylamides

CrystEngComm ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 210-215
Author(s):  
Drew E. Craddock ◽  
McKenzie J. Parks ◽  
Lauren A. Taylor ◽  
Benjamin L. Wagner ◽  
Michael Ruf ◽  
...  
Keyword(s):  
Structural Boundary

Spatially larger naphthylamides than previously reported diarylamides promote greater structural variance of substituents during the pairwise assembly of quasienantiomers.

Aerospace Thermal-Structural Testing Technology

1997 ◽  
Vol 50 (9) ◽  
pp. 477-498 ◽  
Author(s):  
Earl A. Thornton
Keyword(s):  
High Speed ◽  
Structural Testing ◽  
Aerodynamic Heating ◽  
Heating And Cooling ◽  
Structural Test ◽  
Space Experiments ◽  
Test Technology ◽  
Testing Technology ◽  
Structural Tests ◽  
Structural Boundary

This review article describes aerospace thermal-structural testing technology. It begins with discussions of aerodynamic heating and space radiation heating. The review continues with a general discussion of thermal-structural test technology including heating and cooling, instrumentation, and thermal-structural boundary conditions. Then illustrative thermal structural tests are presented for high speed flight in the atmosphere and flight in space. Experiments conducted in the laboratory as well as flight tests are described. Several experiments are reviewed to demonstrate the diversity of thermal-structural phenomena. This article includes 120 references.

Influences of subsurface geological structure neighboring geological repository on earthquake motion of the site

2009 ◽  
Vol 1193 ◽  
Author(s):  
Taishi Oouchi ◽  
Hiroyuki Tsuchi ◽  
Tetsuya Ota ◽  
Koji Hane ◽  
Toru Sasaki
Keyword(s):  
Ground Motion ◽  
Velocity Structure ◽  
Geological Structure ◽  
Earthquake Ground Motion ◽  
Seismic Motion ◽  
Earthquake Resistant Design ◽  
Geological Repository ◽  
Subsurface Layers ◽  
Deep Underground ◽  
Structural Boundary

AbstractAccording to recent seismic observation records, there are some cases where unexpectedly large seismic motion was observed deep underground and that was larger than at the surface. The factors influencing such phenomena are assumed to be deep geological structures with topographic irregularity, velocity structure and non-linearity of subsurface layers. These factors should be taken into account in the earthquake-resistant design of a geological repository. The influence of a deep underground geological structure with topographic irregularity on ground motion has been studied and it has been confirmed that such a structure have a significant impact on ground motion and the constructive interference of waves may result in strong earthquake ground motion in the vicinity of a structural boundary deep underground.

A seismic-based cross-section of the Grenville Orogen in southern Ontario and western Quebec

2000 ◽  
Vol 37 (2-3) ◽  
pp. 183-192 ◽  
Author(s):  
D J White ◽  
D A Forsyth ◽  
I Asudeh ◽  
S D Carr ◽  
H Wu ◽  
...  
Keyword(s):  
Cross Section ◽  
Seismic Refraction ◽  
Shear Zones ◽  
Tectonic Zone ◽  
Grenville Province ◽  
Crustal Layer ◽  
Seismic Reflection Data ◽  
Velocity Models ◽  
Laurentian Margin ◽  
Structural Boundary

A schematic crustal cross-section is presented for the southwestern Grenville Province based on reprocessed Lithoprobe near-vertical incidence seismic reflection data and compiled seismic refraction - wide-angle velocity models interpreted with geological constraints. The schematic crustal architecture of the southwest Grenville Province from southeast to northwest comprises allochthonous crustal elements (Frontenac-Adirondack Belt and Composite Arc Belt) that were assembled prior to ca. 1160 Ma, and then deformed and transported northwest over reworked rocks of pre-Grenvillian Laurentia and the Laurentian margin primarily between 1120 and 980 Ma. Reworked pre-Grenvillian Laurentia and Laurentian margin rocks are interpreted to extend at least 350 km southeast of the Grenville Front beneath all of the Composite Arc Belt. Three major structural boundary zones (the Grenville Front and adjacent Grenville Front Tectonic Zone, the Central Metasedimentary Belt boundary thrust zone, and the Elzevir-Frontenac boundary zone) have been identified across the region of the cross-section based on their prominent geophysical signatures comprising broad zones of southeast-dipping reflections and shallowing of mid-crustal velocity contours by 12-15 km. The structural boundary zones accommodated southeast over northwest crustal stacking at successively earlier times during orogeny (ca. 1010-980 Ma, 1080-1060 Ma, and 1170-1160 Ma, respectively). These shear zones root within an interpreted gently southeast-dipping regional décollement at a depth of 25-30 km corresponding to the top of a high-velocity lower crustal layer.

scholarly journals Is the Eastern Denali fault still active?

Geology ◽  
2021 ◽  
Author(s):  
Minhee Choi ◽  
David W. Eaton ◽  
Eva Enkelmann
Keyword(s):  
Bering Sea ◽  
Active Fault ◽  
Strike Slip ◽  
Historical Seismicity ◽  
Fault System ◽  
Denali Fault ◽  
Regional Deformation ◽  
Source Mechanisms ◽  
Structural Boundary ◽  
The Bering Sea

The Denali fault, a transcurrent fault system that extends from northwestern Canada across Alaska toward the Bering Sea, is partitioned into segments that exhibit variable levels of historical seismicity. A pair of earthquakes (M 6.2 and 6.3) on 1 May 2017, in proximity to the Eastern Denali fault (EDF), exhibited source mechanisms and stress conditions inconsistent with expectations for strike-slip fault activation. Precise relocation of ~1500 aftershocks revealed distinct fault strands that are oblique to the EDF. Calculated patterns of Coulomb stress show that the first earthquake likely triggered the second one. The EDF parallels the Fairweather transform, which separates the obliquely colliding Yakutat microplate from North America. In our model, inboard transfer of stress is deforming and shortening the mountainous region between the EDF and the Fairweather transform. This is supported by historical seismicity concentrated southwest of the EDF, suggesting that it now represents a structural boundary that controls regional deformation but is no longer an active fault.

scholarly journals Dating protracted fault activities: microstructures, microchemistry and geochronology of the Vaikrita Thrust, Main Central Thrust zone, Garhwal Himalaya, NW India

2018 ◽  
Vol 481 (1) ◽  
pp. 127-146 ◽  
Author(s):  
Chiara Montemagni ◽  
Chiara Montomoli ◽  
Salvatore Iaccarino ◽  
Rodolfo Carosi ◽  
Arvind K. Jain ◽  
...  
Keyword(s):  
Electron Microprobe ◽  
Garhwal Himalaya ◽  
Main Central Thrust ◽  
Content Type ◽  
Mylonitic Foliation ◽  
Link Type ◽  
Thrust Zone ◽  
Supplementary Material ◽  
Structural Boundary

AbstractThe timing of shearing along the Vaikrita Thrust, the upper structural boundary of the Main Central Thrust Zone in the Garhwal Himalaya, was constrained by combined microstructural, microchemical and geochronological investigations. Three different biotite–muscovite growth and recrystallization episodes were observed: a relict mica-1; mica-2 along the main mylonitic foliation; and mica-3 in coronitic structures around garnet during its breakdown. Electron microprobe analyses of biotite showed chloritization and a bimodal composition of biotite-2 in one sample. Muscovite-2 and muscovite-3 differed in composition from each other. Biotite and muscovite 39Ar–40Ar age spectra from all samples showed both inter- and intra-sample discrepancies. Biotite step-ages ranged between 8.6 and 16 Ma and muscovite step-ages between 3.6 and 7.8 Ma. These ages cannot be interpreted as ‘cooling ages’ because samples from the same outcrop cooled simultaneously. Instead, the Ar systematics reflect sample-specific recrystallization markers. Intergrown impurities were diagnosed by the Ca/K ratios. The age data of biotite were interpreted as a mixture of true biotite-2 (9.00 ± 0.10 Ma) and two alteration products. The negative Cl/K–age correlation identified a Cl-poor muscovite-2 (>7 Ma) and a Cl-rich, post-deformational, coronitic muscovite-3 grown at ≤5.88 ± 0.03 Ma. The Vaikrita Thrust was active at least from 9 to 6 Ma at c. 600°C; its movement had ended by 6 Ma.Supplementary material: Thermometric and 39Ar–40Ar data are available at https://doi.org/10.6084/m9.figshare.c.4069076

Vibration of Plate Structures Solved by DQEM Using EDQ

2003 ◽  
Author(s):  
Chang-New Chen
Keyword(s):  
Numerical Algorithms ◽  
Element Model ◽  
Equation System ◽  
Solution Procedure ◽  
Analysis Model ◽  
Engineering Structures ◽  
Discrete Eigenvalue ◽  
Plate Structures ◽  
Wide Range ◽  
Structural Boundary

The vibration of plate structures is solved by DQEM using EDQ. In the DQEM discretization, EDQ is used to define the discrete element model. Discrete eigenvalue equations defined at interior discrete points in all elements, transition conditions defined on the inter-element boundary of two adjacent elements and boundary conditions at the structural boundary form the overall discrete eigenvalue equation system. Numerical results obtained by the developed numerical algorithms are presented. They demonstrate the developed numerical solution procedure. This vibration analysis model can be used to solve wide range of offshore engineering structures.

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