Evidence for Dominant Role of Tunneling in Condensed Phases and at High Temperatures: Double Hydrogen Transfer in Porphycenes

2016 ◽  
Vol 7 (2) ◽  
pp. 283-288 ◽  
Author(s):  
Piotr Ciąćka ◽  
Piotr Fita ◽  
Arkadiusz Listkowski ◽  
Czesław Radzewicz ◽  
Jacek Waluk
Keyword(s):  
High Temperatures ◽  
Hydrogen Transfer ◽  
Dominant Role ◽  
Condensed Phases ◽  
Double Hydrogen

scholarly journals Experimental observations of fluidized beds at high temperatures

2016 ◽  
Vol 1 (1) ◽  
pp. 9 ◽  
Author(s):  
Paola Lettieri ◽  
David Newton ◽  
John G. Yates
Keyword(s):  
High Temperatures ◽  
Dominant Role ◽  
Effect Of Temperature ◽  
Interparticle Forces ◽  
Collapse Time ◽  
Experimental Values ◽  
Increasing Temperature ◽  
Fcc Catalysts

<p>The objective of this paper is to report some experimental observations on the effect of temperature on the fluidization of three fresh FCC catalysts and an equilibrium (E-cat) FCC. The bed collapse test was used as a quantitative test to characterise the <em>fluidization quality </em>of these materials with increasing temperatures. It provides a sensitive and discriminating means of assessing the changes in the materials’ responses between low and high temperature fluidization. The standardised collapse time, SCT, was calculated from the collapse profiles and the experimental values obtained for the FCC catalysts are reported in this paper. The fluidization quality of the fresh FCC catalysts improved with increasing temperature, as indicated by the increase in SCT values. On the other hand, the standardised collapse time of the E-cat FCC decreased with increasing temperature as the catalyst became less aeratable. Changes of the surface properties of this material occurred on increasing temperature. The flow behaviour of the E-cat catalyst was compared with fluidization of a Group C material. The aeratability of this latter material decreased exponentially, due to the dominant role of the interparticle forces over the hydrodynamic forces, with increasing temperature. The use of classical concepts such as the non bubbling ratio, u<sub>mb</sub>/u<sub>mf</sub>, to describe fluidization at low and high temperatures is discussed. Experimental u<sub>mb</sub>/u<sub>mf </sub>values obtained for the fresh FCC catalysts are compared with predictions.</p>

Non-classical effects in proton or hydrogen transfer

2016 ◽  
Vol 88 (10-11) ◽  
pp. 1063-1071 ◽  
Author(s):  
Jacek Waluk
Keyword(s):  
Hydrogen Transfer ◽  
Organic Molecules ◽  
Vibrational Excitation ◽  
Single Molecules ◽  
Electronic States ◽  
Condensed Phases ◽  
Vibrational Modes ◽  
Transfer Path ◽  
Multidimensional Process

AbstractResults of thorough investigations of tautomerism in the ground and excited electronic states performed for various organic molecules under different regimes: condensed phases, isolated and single molecules, with a special emphasis on porphycene, a porphyrin isomer, demonstrate that, in order to precisely describe the proton/hydrogen transfer path, one has to explicitly consider tunneling. Tautomerization is a multidimensional process, controlled by excitation of specific vibrational modes. Vibrational excitation can both enhance or hinder the reaction. The role of specific vibrational modes can now be assessed, even at the level of single molecules.

Chronic Pain: Fundamental Scientific Considerations, Specifically for Legal Claims

2013 ◽  
Vol 18 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Robert J. Barth
Keyword(s):  
Health Outcomes ◽  
Pain Perception ◽  
Driving Forces ◽  
Psychological Treatment ◽  
Dominant Role ◽  
Meta Analysis ◽  
General Medicine ◽  
Pain Syndrome ◽  
Problematic Relationship

Abstract Scientific findings have indicated that psychological and social factors are the driving forces behind most chronic benign pain presentations, especially in a claim context, and are relevant to at least three of the AMA Guides publications: AMA Guides to Evaluation of Disease and Injury Causation, AMA Guides to Work Ability and Return to Work, and AMA Guides to the Evaluation of Permanent Impairment. The author reviews and summarizes studies that have identified the dominant role of financial, psychological, and other non–general medicine factors in patients who report low back pain. For example, one meta-analysis found that compensation results in an increase in pain perception and a reduction in the ability to benefit from medical and psychological treatment. Other studies have found a correlation between the level of compensation and health outcomes (greater compensation is associated with worse outcomes), and legal systems that discourage compensation for pain produce better health outcomes. One study found that, among persons with carpal tunnel syndrome, claimants had worse outcomes than nonclaimants despite receiving more treatment; another examined the problematic relationship between complex regional pain syndrome (CRPS) and compensation and found that cases of CRPS are dominated by legal claims, a disparity that highlights the dominant role of compensation. Workers’ compensation claimants are almost never evaluated for personality disorders or mental illness. The article concludes with recommendations that evaluators can consider in individual cases.

НЕКОТОРЫЕ ОСОБЕННОСТИ РАСПРОСТРАНЕННОСТИ РЕСПИРАТОРНОЙ АЛЛЕРГИИ НА ЮГЕ РОССИИ

2019 ◽  
Author(s):  
D.Sh. Macharadze
Keyword(s):  
Dominant Role ◽  
Pollen Allergy ◽  
Respiratory Allergy ◽  
House Dust Mites ◽  
Dust Mites ◽  
The Past ◽  
Regional Features ◽  
Respiratory Allergies ◽  
Southern Russia

В обзорной статье приведены данные по распространенности респираторной аллергии - аллергического ринита и бронхиальной астмы на юге России, опубликованные за последние десятилетия. Показана доминирующая роль пыльцевой аллергии практически во всем южном регионе России. В Чеченской Республике у больных респираторной аллергией обнаружена сходная частота встречаемости сенсибилизации к клещам домашней пыли и пыльце злаковых трав (51,1 и 52,5 соответственно), тогда как сенсибилизация к пыльце амброзии и полыни встречалась в 3 раза реже (26,6 и 20,7 соответственно) по сравнению с соседними регионами юга России. Эти данные демонстрируют климатогеографические, экологические и другие региональные особенности в распространении респираторной аллергии.The review article presents data on the prevalence of respiratory allergy - allergic rhinitis and bronchial asthma in southern Russia, published over the past decades. The dominant role of pollen allergy is shown in almost the entire southern region of Russia. In the Chechen Republic, sensitization to house dust mites and grass pollen was found in patients with respiratory allergy equally (51.1 and 52.5, respectively), whereas ragweed and mugwort sensitization was 3 times less (26.6 and 20.7, respectively) compared with the neighboring regions of southern Russia. These data demonstrate climate-geographical, environmental and other regional features in the prevalence of respiratory allergies.

KEGAGALAN PRIVATISASI BUMN DI ERA REZIM ORDE BARU DALAM PERSPEKTIF EKONOMI POLITIK

Wacana Publik ◽  
2019 ◽  
Vol 12 (02) ◽  
Author(s):  
Syamsul Ma'arif
Keyword(s):  
Market Economy ◽  
Free Market ◽  
Dominant Role ◽  
The State ◽  
Early Years ◽  
New Order ◽  
Free Market Economy ◽  
Economic Sectors ◽  
Role Of The State

After had being carried out nationalization and hostility against west countries, the New Order regime made important decision to change Indonesia economic direction from etatism system to free market economy. A set of policies were taken in order private sector could play major role in economic. However, when another economic sectors were reformed substantially, effords to reform the State Owned Enterprises had failed. The State Owned Enterprise, in fact, remained to play dominant role like early years of guided democracy era. Role of the State Owned Enterprises was more and more powerfull). The main problem of reforms finally lied on reality that vested interest of bureaucrats (civil or military) was so large that could’nt been overcome. 

Conclusion

2018 ◽  
Author(s):  
Ildar Garipzanov
Keyword(s):  
Cultural History ◽  
Middle Ages ◽  
Late Antiquity ◽  
Western Europe ◽  
Dominant Role ◽  
Ninth Century ◽  
Sources Of Authority ◽  
History Of ◽  
Historical Periods

The concluding chapter highlights how the cultural history of graphic signs of authority in late antiquity and the early Middle Ages encapsulated the profound transformation of political culture in the Mediterranean and Europe from approximately the fourth to ninth centuries. It also reflects on the transcendent sources of authority in these historical periods, and the role of graphic signs in highlighting this connection. Finally, it warns that, despite the apparent dominant role of the sign of the cross and cruciform graphic devices in providing access to transcendent protection and support in ninth-century Western Europe, some people could still employ alternative graphic signs deriving from older occult traditions in their recourse to transcendent powers.

scholarly journals Molecular Dynamics of Chloroplast Membranes Isolated from Wild-Type Barley and a Brassinosteroid-Deficient Mutant Acclimated to Low and High Temperatures

Biomolecules ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 27
Author(s):  
Iwona Sadura ◽  
Dariusz Latowski ◽  
Jana Oklestkova ◽  
Damian Gruszka ◽  
Marek Chyc ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Temperature Stress ◽  
High Temperatures ◽  
Biological Membrane ◽  
Hydrophobic Core ◽  
Wild Type ◽  
Chloroplast Membranes ◽  
Paramagnetic Resonance ◽  
Photosynthetic Membranes

Plants have developed various acclimation strategies in order to counteract the negative effects of abiotic stresses (including temperature stress), and biological membranes are important elements in these strategies. Brassinosteroids (BR) are plant steroid hormones that regulate plant growth and development and modulate their reaction against many environmental stresses including temperature stress, but their role in modifying the properties of the biological membrane is poorly known. In this paper, we characterise the molecular dynamics of chloroplast membranes that had been isolated from wild-type and a BR-deficient barley mutant that had been acclimated to low and high temperatures in order to enrich the knowledge about the role of BR as regulators of the dynamics of the photosynthetic membranes. The molecular dynamics of the membranes was investigated using electron paramagnetic resonance (EPR) spectroscopy in both a hydrophilic and hydrophobic area of the membranes. The content of BR was determined, and other important membrane components that affect their molecular dynamics such as chlorophylls, carotenoids and fatty acids in these membranes were also determined. The chloroplast membranes of the BR-mutant had a higher degree of rigidification than the membranes of the wild type. In the hydrophilic area, the most visible differences were observed in plants that had been grown at 20 °C, whereas in the hydrophobic core, they were visible at both 20 and 5 °C. There were no differences in the molecular dynamics of the studied membranes in the chloroplast membranes that had been isolated from plants that had been grown at 27 °C. The role of BR in regulating the molecular dynamics of the photosynthetic membranes will be discussed against the background of an analysis of the photosynthetic pigments and fatty acid composition in the chloroplasts.

The role of acetic acid in FeCO3 scale deposition on CO2 corrosion of API X65 carbon steel under high temperatures

2021 ◽  
pp. 1-12
Author(s):  
Bernardo Augusto Farah Santos ◽  
Rhuan Costa Souza ◽  
Maria Eduarda Dias Serenario ◽  
Eugenio Pena Mendes Junior ◽  
Thiago Araujo Simões ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Carbon Steel ◽  
High Temperatures ◽  
Co2 Corrosion ◽  
Scale Deposition

scholarly journals Revealing the role of excited state proton transfer (ESPT) in excited state hydrogen transfer (ESHT): systematic study in phenol–(NH3)n clusters

2021 ◽  
Author(s):  
Christophe Jouvet ◽  
Mitsuhiko Miyazaki ◽  
Masaaki Fujii
Keyword(s):  
Excited State ◽  
Proton Transfer ◽  
Systematic Study ◽  
General Model ◽  
Hydrogen Transfer ◽  
Excited State Proton Transfer

A general model of excited state hydrogen transfer (ESHT) which unifies ESHT and the excited state proton transfer (ESPT) is presented from experimental and theoretical works on phenol–(NH3)n. The hidden role of ESPT is revealed.

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