INFRARED ABSORPTION OF FORMALDEHYDE AT LOW TEMPERATURES: EVIDENCE FOR MULTIPLE TRAPPING SITES IN AN ARGON MATRIX

1962 ◽  
Vol 40 (1) ◽  
pp. 85-91 ◽  
Author(s):  
K. B. Harvey ◽  
J. F. Ogilvie
Keyword(s):  
Fine Structure ◽  
Infrared Absorption ◽  
Low Temperatures ◽  
Point Of View ◽  
Monomeric Form ◽  
Argon Matrix ◽  
Inert Matrix ◽  
Multiple Trapping ◽  
The Matrix ◽  
Trapping Sites

The infrared absorption of formaldehyde in both the polycrystalline and the monomeric form has been measured at 4 °K. In the latter case the molecules were suspended in an inert matrix of Ar or N2. The fine structure of the matrix spectra is discussed from the point of view of rotation of the monomers but this interpretation is ruled out in favor of one based on multiple trapping sites in the matrix.

PRESSURE-INDUCED INFRARED ABSORPTION OF GASEOUS HYDROGEN AND DEUTERIUM AT LOW TEMPERATURES: I. THE INTEGRATED ABSORPTION COEFFICIENTS

1965 ◽  
Vol 43 (5) ◽  
pp. 818-828 ◽  
Author(s):  
A. Watanabe ◽  
H. L. Welsh
Keyword(s):  
Fine Structure ◽  
Low Temperature ◽  
Infrared Absorption ◽  
Low Temperatures ◽  
Bound States ◽  
Gaseous Hydrogen ◽  
Absorption Coefficients ◽  
Spectroscopic Evidence ◽  
Mixture Formula ◽  
Path Lengths

The pressure-induced infrared absorption of the fundamental band of hydrogen, in the pure gas and in a H2–He mixture, and of deuterium was studied in the temperature range from 18 °K to 77 °K. Path lengths up to 13.6 m at 1 atm or somewhat higher were obtained in a multiple-traversal cell cooled by liquid hydrogen or nitrogen. The binary coefficient [Formula: see text] for hydrogen shows a rise at low temperature, indicating the existence of bound states predicted by theory for the (H2)2 complex. The effect is more pronounced for deuterium. For the H2–He mixture [Formula: see text] decreases monotonically with temperature, thus showing no evidence of bound states for H2–He pairs. Fine structure at the maxima of the pressure-induced band in hydrogen and deuterium gives direct spectroscopic evidence of bound states of (H2)2 and (D2)2 complexes at low temperatures.

Ultrastructure of the soil fungus, Geomyces pannorus

1984 ◽  
Vol 42 ◽  
pp. 738-739
Author(s):  
J. A. Traquair ◽  
E. G. Kokko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fine Structure ◽  
Low Temperatures ◽  
Soil Fungus ◽  
Organic Soils ◽  
Anatomical Studies ◽  
Transmission Electron ◽  
Electron Microscopical ◽  
Scanning Electron

With the advent of improved dehydration techniques, scanning electron microscopy has become routine in anatomical studies of fungi. Fine structure of hyphae and spore surfaces has been illustrated for many hyphomycetes, and yet, the ultrastructure of the ubiquitous soil fungus, Geomyces pannorus (Link) Sigler & Carmichael has been neglected. This presentation shows that scanning and transmission electron microscopical data must be correlated in resolving septal structure and conidial release in G. pannorus.Although it is reported to be cellulolytic but not keratinolytic, G. pannorus is found on human skin, animals, birds, mushrooms, dung, roots, and frozen meat in addition to various organic soils. In fact, it readily adapts to growth at low temperatures.

Optical Transitions in Chalcogenide Glasses From the Point of View of a Barrier-Cluster Model

2008 ◽  
Vol 39-40 ◽  
pp. 253-256
Author(s):  
Ivan Baník
Keyword(s):  
Optical Absorption ◽  
Low Temperatures ◽  
Cluster Model ◽  
Chalcogenide Glasses ◽  
Temperature Shift ◽  
Point Of View ◽  
Optical Transitions ◽  
Influence Of Temperature ◽  
Exponential Tails ◽  
Influence Of Temperature On

A barrier-cluster model of chalcogenide glasses is employed to analyze optical transitions near the absorption edge. The influence of temperature on the optical absorption is studied. The model is used to explain the temperature shift of exponential tails of the optical absorption and the temperature dependence of the optical forbidden-band width at low temperatures.

scholarly journals Matrix integrals & finite holography

2021 ◽  
Vol 2021 (6) ◽  
Author(s):  
Dionysios Anninos ◽  
Beatrix Mühlmann
Keyword(s):  
Critical Exponents ◽  
Continuum Theory ◽  
Point Of View ◽  
Leading Order ◽  
Minimal Models ◽  
Point Evaluation ◽  
Brst Cohomology ◽  
Matrix Integrals ◽  
The Matrix ◽  
The Continuum

Abstract We explore the conjectured duality between a class of large N matrix integrals, known as multicritical matrix integrals (MMI), and the series (2m − 1, 2) of non-unitary minimal models on a fluctuating background. We match the critical exponents of the leading order planar expansion of MMI, to those of the continuum theory on an S2 topology. From the MMI perspective this is done both through a multi-vertex diagrammatic expansion, thereby revealing novel combinatorial expressions, as well as through a systematic saddle point evaluation of the matrix integral as a function of its parameters. From the continuum point of view the corresponding critical exponents are obtained upon computing the partition function in the presence of a given conformal primary. Further to this, we elaborate on a Hilbert space of the continuum theory, and the putative finiteness thereof, on both an S2 and a T2 topology using BRST cohomology considerations. Matrix integrals support this finiteness.

Fibre-Matrix Interface Development during High Temperature Exposition of Long Fibre Reinforced SiOC Matrix

2013 ◽  
Vol 592-593 ◽  
pp. 401-404
Author(s):  
Zdeněk Chlup ◽  
Martin Černý ◽  
Adam Strachota ◽  
Martina Halasova ◽  
Ivo Dlouhý
Keyword(s):  
High Temperature ◽  
Crack Formation ◽  
Fracture Behaviour ◽  
Point Of View ◽  
Reinforced Composites ◽  
Matrix Interface ◽  
Significant Damage ◽  
The Matrix ◽  
Fibre Matrix ◽  
Fibre Reinforced Composites

The fracture behaviour of long fibre reinforced composites is predetermined mainly by properties of fibre-matrix interface. The matrix prepared by pyrolysis of polysiloxane resin possesses ability to resist high temperatures without significant damage under oxidising atmosphere. The application is therefore limited by fibres and possible changes in the fibre matrix interface. The study of development of interface during high temperature exposition is the main aim of this contribution. Application of various techniques as FIB, GIS, TEM, XRD allowed to monitor microstructural changes in the interface of selected places without additional damage caused by preparation. Additionally, it was possible to obtain information about damage, the crack formation, caused by the heat treatment from the fracture mechanics point of view.

scholarly journals MYSTERY AS A META-GENRE IN THE DRAMA OF THE TWENTIETH CENTURY

2021 ◽  
pp. 18-26
Author(s):  
K. Oliinyk
Keyword(s):  
Twentieth Century ◽  
World Order ◽  
Semantic Content ◽  
Point Of View ◽  
Dramatic Works ◽  
Life And Death ◽  
The Matrix ◽  
General Feeling ◽  
The Aesthetic ◽  
Definition Of

The article examines the specificity of existence of the renewed mystery genre as a meta genre in the twentieth century. The main literary study views on the definition of ancient and medieval / Christian ritual mystery are analyzed. The beginning of the twentieth century was full of a general feeling of catastrophe and tragic hopelessness. In artistic terms, the consequence of this was the activation of Christian issues, motives, plots, religious genres (miracles, morality and mystery). The most universal from the point of view of the ideological message and content for the writers of the twentieth century. was the matrix of the medieval mystery, which retained the ritual basis in its primary structure. This made it possible for the multilevel organization of the action and the space for it. The genre of medieval mystery is being modified, it ceases to be a purely form of religious action and acquires the quality of a meta genre. There is a transition from the religious sphere to the secular one, and the aesthetic one is replacing the didactic load. Mystery begins to exist on the edge of genres as a synthetic formation, showing intentions to “help” other genres. A large number of dramatic works of the twentieth century. ("Forest Song" by Lesia Ukrainka, "Iconostasis of Ukraine" by Vіra Vovk) comes close to the mystery, using its archetypal components: the ideas of faith in the absolute beginning, governing the eternal rotation of life and death, world order and harmony, death and rebirth, transformations of the human soul, chosenness and initiation associated with trials, sacrifice, deepening into mysticism. Such works are a certain imitation with elements of mythological or religious subjects. So, the twentieth century, actualizes a certain involvement of the semantic content of dramas to the mysteries, bringing the mystery to the level of the meta genre.

scholarly journals Supercritical Fluid Extraction of Polychlorinated Biphenyls and Organochlorine Pesticides from Freeze-Dried Tissue of Marine Mussel, Mytilus eduli

1997 ◽  
Vol 80 (6) ◽  
pp. 1336-1346 ◽  
Author(s):  
Wesley J Yoo ◽  
Larry T Taylor
Keyword(s):  
Polychlorinated Biphenyls ◽  
Organochlorine Pesticides ◽  
Supercritical Fluid ◽  
Activated Alumina ◽  
Mussel Tissue ◽  
Inert Matrix ◽  
Freeze Dried ◽  
The Matrix ◽  
On Line ◽  
Lower Temperature

Abstract Supercritical fluid extractions (SFEs) of 21 polychlorinated biphenyls (PCBs) and 8 organochlorine pesticides (OCPs) from freeze-dried mussel tissue are compared with traditional Soxhlet extractions. The aim was to determine the efficacy of supercritical CO2 to extract these 2 classes of lipophilic compounds. A spike study to determine the feasibility of on-line cleanup by inclusion of an inert matrix (activated alumina) in the extraction vessel showed that the chemical integrity of the PCBs was not compromised, whereas some DDTs were decomposed to their respective metabolites. Relatively long static extraction time, higher density, and lower temperature yielded quantitative recoveries of PCBs from freeze-dried mussel tissue with good reproducibilities. Recoveries of OCPs were nonquantitative and highly variable. Finally, the efficacy of fluoroform (CHF3) as an alternative supercritical fluid to selectively extract PCBs and OCPs was studied. Fluoroform yielded nonquantitative and variable recoveries of PCBs and OCPs, but its use eliminated the need for in situ alumina to retain coextracted lipids from the matrix.

1H-1,3-Diazepines and Ketenimines from Cyanotetrazolopyridines

2008 ◽  
Vol 61 (8) ◽  
pp. 592 ◽  
Author(s):  
Chris Addicott ◽  
Curt Wentrup
Keyword(s):  
Infrared Spectra ◽  
Ring Opening ◽  
Ring Expansion ◽  
Secondary Amines ◽  
Argon Matrix ◽  
The Matrix ◽  
Nitrogen Elimination ◽  
Isolated Species

Cyano-substituted tetrazolo[1,5-a]pyridines/2-azidopyridines 8T and 15T undergo thermal ring opening to the azides 8A and 15A. Solution photolysis causes nitrogen elimination and ring expansion to 1,3-diazacyclohepta-1,2,4,6-tetraenes 10 and 17, which react with alcohols to afford 2-alkoxy-1H-1,3-diazepines, with secondary amines to 2-dialkylamino-5H-1,3-diazepines, and with water to 1,3-diazepin-2-ones (12–14, 19, 21). Argon matrix photolysis of the azides affords the diazacycloheptatetraenes 10 and 17 as principal products together with ring-opened dicyanovinylketenimines 11 and 18. The matrix-isolated species were identified on the basis of comparison of the infrared spectra with those calculated at the B3LYP/6–31+G* level.

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