scholarly journals Cyclodextrins AS Dominant Chiral Selective Agents in the Capillary Separation Techniques

2021 ◽  
Author(s):  
Zoltán Juvancz ◽  
Rita Bodáné-Kendrovics ◽  
Lajos Szente ◽  
Dóra Maklári
Keyword(s):  
High Efficiency ◽  
Dominant Role ◽  
Shape Selectivity ◽  
Capillary Columns ◽  
Chiral Separations ◽  
Selective Agents ◽  
Chiral Selectivity ◽  
Chemical Background ◽  
Physical And Chemical

This review paper shows the dominant role of the cyclodextrins in the chiral separations using capillary columns (GC, SFC, CE). The cyclodextrins (CDs) have extremely broad chiral selectivity spectra because they have several different chiral recognition sites in various arrangements and various interaction modes. Their chiral selectivity features can further improve with their various substitutions. Their selectivities are moderate therefore they need high efficiency separations (capillary columns) for good chiral resolutions. The shape selectivity of cyclodextrins is also shown with non-chiral isomers too. The utility of the cyclodextrins is demonstrated with several examples based on the personal observations of authors and critical review of literature. The theoretical backgrounds of their chiral recognitions (e.g. H-bond interaction, inclusion, induced fit) are discussed in depth. This paper is not application oriented but is dealing with mostly on the physical and chemical background of separations using CDs.

scholarly journals Wheat Straw Biochar as a Specific Sorbent of Cobalt in Soil

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2462 ◽  
Author(s):  
Agnieszka Medyńska-Juraszek ◽  
Irmina Ćwieląg-Piasecka ◽  
Maria Jerzykiewicz ◽  
Justyna Trynda
Keyword(s):  
Wheat Straw ◽  
Contaminated Soils ◽  
High Efficiency ◽  
Dominant Role ◽  
Low Cost ◽  
Material Efficiency ◽  
Ft Ir ◽  
Heavy Metal Adsorbent

There is an urgent need to search for new sorbents of pollutants presently delivered to the environment. Recently biochar has received much attention as a low-cost, highly effective heavy metal adsorbent. Biochar has been identified as an efficient material for cobalt (Co) immobilization from waters; however, little is known about the role of Co immobilization in soil. Hence, in this study, a batch experiment and a long-term incubation experiment with biochar application to multi-contaminated soil with distinct properties (sand, loam) were conducted to provide a brief explanation of the potential mechanisms of Co (II) sorption on wheat straw biochar and to describe additional processes that modify material efficiency for metal sorption in soil. The soil treatments with 5% (v/w) wheat straw biochar proved to be efficient in reducing Co mobility and bioavailability. The mechanism of these processes could be related to direct and indirect effects of biochar incorporation into soil. The FT-IR analysis confirmed that hydroxyl and carboxyl groups present on the biochar surface played a dominant role in Co (II) surface complexation. The combined effect of pH, metal complexation capacity, and the presence of Fe and Mn oxides added to wheat straw biochar resulted in an effective reduction of soluble Co (II), showing high efficiency of this material for cobalt sorption in contaminated soils.

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.

Clustering-Triggered Efficient Room Temperature Phosphorescence from Nonconventional Luminophores

2019 ◽  
Author(s):  
Shuyuan Zheng ◽  
Taiping Hu ◽  
Xin Bin ◽  
Yunzhong Wang ◽  
Yuanping Yi ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Efficiency ◽  
Spin Orbit Coupling ◽  
Design Rationale ◽  
Emission Mechanism ◽  
Room Temperature Phosphorescence ◽  
Electronic Interactions ◽  
Energy Gaps ◽  
Theoretical Results

Pure organic room temperature phosphorescence (RTP) and luminescence from nonconventional luminophores have gained increasing attention. However, it remains challenging to achieve efficient RTP from unorthodox luminophores, on account of the unsophisticated understanding of the emission mechanism. Here we propose a strategy to realize efficient RTP in nonconventional luminophores through incorporation of lone pairs together with clustering and effective electronic interactions. The former promotes spin-orbit coupling and boost the consequent intersystem crossing, whereas the latter narrows energy gaps and stabilizes the triplets, thus synergistically affording remarkable RTP. Experimental and theoretical results of urea and its derivatives verify the design rationale. Remarkably, RTP from thiourea solids with unprecedentedly high efficiency of up to 24.5% is obtained. Further control experiments testify the crucial role of through-space delocalization on the emission. These results would spur the future fabrication of nonconventional phosphors, and moreover should advance understanding of the underlying emission mechanism.<br>

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.

The critical role of the coordination sphere in the high-efficiency blue-light emission from aminopyrazine metal-organic polymers

2021 ◽  
Vol 186 ◽  
pp. 109025
Author(s):  
João Humberto Dias Campos ◽  
Meiry Edivirges Alvarenga ◽  
Maykon Alves Lemes ◽  
José Antônio do Nascimento Neto ◽  
Freddy Fernandes Guimarães ◽  
...  
Keyword(s):  
Blue Light ◽  
Coordination Sphere ◽  
High Efficiency ◽  
Light Emission ◽  
Critical Role ◽  
Organic Polymers ◽  
Blue Light Emission ◽  
Metal Organic

Unprecedentedly high efficiency for photocatalytic conversion of methane to methanol over Au–Pd/TiO2 – what is the role of each component in the system?

2021 ◽  
Author(s):  
Xiaojiao Cai ◽  
Siyuan Fang ◽  
Yun Hang Hu
Keyword(s):  
Methane Conversion ◽  
High Efficiency ◽  
Mild Conditions ◽  
Highly Efficient ◽  
System P ◽  
Conversion Of Methane

Direct and highly efficient methane conversion to methanol under mild conditions is achieved via photocatalysis over Au–Pd/TiO2.

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