scholarly journals The Problem of Dynamic Process Manifestation in Identification of Organic Compounds by NMR Spectroscopy

2020 ◽  
Vol 10 (1) ◽  
pp. 63-76
Author(s):  
N. E. Kuz’mina ◽  
S. V. Moiseev ◽  
A. I Luttseva
Keyword(s):  
Nmr Spectroscopy ◽  
Organic Compounds ◽  
Dynamic Process ◽  
Amide Bond ◽  
Dynamic Processes ◽  
Chemical Calculation ◽  
Negative Effects ◽  
Pharmaceutical Substances ◽  
Nonvalent Interactions ◽  
Intramolecular Dynamic

The number, shape and position of NMR spectral lines depend on dynamic processes, and this creates certain difficulties in identification of pharmaceutical substances by NMR spectroscopy. The aim of the paper was to study instances of manifestation of intramolecular dynamic processes that affect identification of organic compounds by NMR, and to illustrate the potential of the methods used for their reduction, as well as associated problems.Materials and methods: 1H and 13C spectra of the following pharmaceutical substances: «buserelin acetate», «valsartan», «goserelin acetate», «iopromide», «clopidogrel hydrogensulfate», «omeprazole», «proroxan», «risperidone», «triptorelin acetate», and «enalapril maleate» were used to demonstrate negative effects of dynamic processes. The spatial structures of conformers were established by 1H-1H ROESY experiments. The quantum-chemical calculation of geometric and thermodynamic characteristics of different conformers was carried out by the PM3 method, and electronic characteristics—by the AM1 method with the help of the HyperChem software.Results: the authors analysed intramolecular dynamic processes which are most commonly encountered in expert work: pyramidal inversion of nitrogen in a heterocyclic compound (risperidone, proroxan, clopidogrel), rotation of molecular fragments around the amide bond (valsartan, iopromide, enalapril), prototropic rearrangements (buserelin, goserelin, omeprazole, triptorelin). The change in exchange rates was explained from the perspective of the change in the system of intra- and intermolecular nonvalent interactions.Conclusions: the use of traditional methods for increasing the rate of dynamic processes (increasing the temperature and changing the solvent) does not always eliminate the negative effects of intramolecular transformations. Methods of smoothing the spectral manifestations of dynamic processes have limited application due to strong intramolecular nonvalent interactions which prevent the conversion of the dynamic process rate into fast exchange. Experts and manufacturers should take into account the manifestation of dynamic processes during identification of pharmaceutical substances by NMR spectroscopy.

scholarly journals Investigations of Museum Indoor Microclimate and Air Quality. Case Study from Romania

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 286
Author(s):  
Dorina Camelia Ilieș ◽  
Florin Marcu ◽  
Tudor Caciora ◽  
Liliana Indrie ◽  
Alexandru Ilieș ◽  
...  
Keyword(s):  
Air Quality ◽  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Construction Materials ◽  
International Standards ◽  
Total Volatile ◽  
Negative Effects ◽  
Museum Exhibits ◽  
Volatile Organic ◽  
Total Volatile Organic Compounds

Poor air quality inside museums is one of the main causes influencing the state of conservation of exhibits. Even if they are mostly placed in a controlled environment because of their construction materials, the exhibits can be very vulnerable to the influence of the internal microclimate. As a consequence, museum exhibits must be protected from potential negative effects. In order to prevent and stop the process of damage of the exhibits, monitoring the main parameters of the microclimate (especially temperature, humidity, and brightness) and keeping them in strict values is extremely important. The present study refers to the investigations and analysis of air quality inside a museum, located in a heritage building, from Romania. The paper focuses on monitoring and analysing temperature of air and walls, relative humidity (RH), CO2, brightness and particulate matters (PM), formaldehyde (HCHO), and total volatile organic compounds (TVOC). The monitoring was carried out in the Summer–Autumn 2020 Campaign, in two different exhibition areas (first floor and basement) and the main warehouse where the exhibits are kept and restored. The analyses aimed both at highlighting the hazard induced by the poor air quality inside the museum that the exhibits face. The results show that this environment is potentially harmful to both exposed items and people. Therefore, the number of days in which the ideal conditions in terms of temperature and RH are met are quite few, the concentration of suspended particles, formaldehyde, and total volatile organic compounds often exceed the limit allowed by the international standards in force. The results represent the basis for the development and implementation of strategies for long-term conservation of exhibits and to ensure a clean environment for employees, restorers, and visitors.

scholarly journals Methodology for Increasing the Efficiency of Dynamic Process Calculations in Elastic Elements of Complex Engineering Constructions

Electronics ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Andriy Andrukhiv ◽  
Maria Sokil ◽  
Solomiia Fedushko ◽  
Yuriy Syerov ◽  
Yaryna Kalambet ◽  
...  
Keyword(s):  
Dynamic Process ◽  
Granular Media ◽  
Homogeneous Medium ◽  
Dynamic Processes ◽  
Analytical Relationship ◽  
Operational Parameters ◽  
Protective Capacity ◽  
Vibration Displacement ◽  
Complex Engineering ◽  
Elastic Elements

This study deals with a methodology for increasing the efficiency of dynamic process calculations in elastic elements of complex engineering constructions. We studied the complex dynamic processes in a simple engineering construction, a mechanical system of an elastic body–continuous flow of homogeneous medium. The developed methodology is based on the use of a priori information on some of the vibrations forms, the construction of a “simplified” mathematical model of system dynamics, and the obtaining of an analytical relationship that describe the overall range of factors on the elastic vibrations of system. The methodology is used for cases of complex vibrations of elastic bodies, and the obtained results can serve as a basis for choosing the main technological and operational parameters of elastic elements of mechanisms and machines that perform complex vibrations. The results obtained in this work are the basis for calculating the blast effect on the elements of protective structures in order to increase their protective capacity by improving the method of their attachment or by using additional reinforcement, buff load effects on the elements of drilling strings and dynamic processes that occur during surface strengthening by work hardening in order to avoid resonance phenomena, and technological processes of vibration displacement or vibration separation of granular media.

Determination of Relative Configuration in Organic Compounds by NMR Spectroscopy and Computational Methods

ChemInform ◽  
2007 ◽  
Vol 38 (50) ◽  
Author(s):  
Giuseppe Bifulco ◽  
Paolo Dambruoso ◽  
Luigi Gomez-Paloma ◽  
Raffaele Riccio
Keyword(s):  
Nmr Spectroscopy ◽  
Organic Compounds ◽  
Computational Methods ◽  
Relative Configuration

Rapid screening of pharmaceutical substances for the total content of F-, Cl-, Br-, and S-containing organic compounds

2015 ◽  
Vol 70 (5) ◽  
pp. 242-245
Author(s):  
M. E. Chivarzin ◽  
I. A. Revelsky ◽  
A. V. Nikoshina ◽  
A. N. Buldyzhova ◽  
D. A. Chepelyansky ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Total Content ◽  
Rapid Screening ◽  
Pharmaceutical Substances

Terrorism: Group dynamic and interdisciplinary aspects

2021 ◽  
pp. 79-94
Author(s):  
Thomas Wenzel ◽  
Reem Alksiri ◽  
Anthony F. Chen
Keyword(s):  
Human Rights ◽  
Transitional Justice ◽  
Dynamic Process ◽  
The Other ◽  
Dynamic Processes ◽  
Group Dynamic ◽  
Complex Background ◽  
Basic Concepts ◽  
Extreme Violence ◽  
Specific Impact

In this chapter, we offer an interdisciplinary and group-focused model to examine how extreme violence develops, and discuss aspects of interventions for prevention, specifically with regard to terrorism and its many forms. We argue that an analysis of terrorism must be more open, and include research into the perpetrators of extreme violence such as genocide. In general, we see the breakdown of empathy, a group dynamic process that creates the image of ‘the other’ and the violation of basic concepts of humanitarian and human rights laws, as a precondition to terrorism when viewed as a subtype of extreme violence. In recent years, Internet-based and large multinational groups have gained importance, a factor that is insufficiently considered, meaning that more attention is needed on group dynamic processes as drivers of extreme violence. Our interpretation uses models such as that developed by the group analyst Vamik Volkan, and others, including that of chosen trauma. We discuss these factors together with possible strategies to aid transitional justice and contribute to the rehabilitation of victims and perpetrators. The specific impact of each act of terrorism and the needs of victims and society to recover reflect the complex background of each event, and of the contexts in which the crimes were committed.

Emotions and backlash in US society and politics

2020 ◽  
Vol 22 (4) ◽  
pp. 609-618 ◽  
Author(s):  
Roger Petersen
Keyword(s):  
United States ◽  
Dynamic Process ◽  
The United States ◽  
Dynamic Processes ◽  
Complex Emotion ◽  
Political Groups

Alter and Zurn’s framework identifies ‘frequent companions’ to backlash politics including emotive elements. This article addresses those emotive elements. In particular, it defines and unpacks the complex emotion of indignation, an emotion that sets off a dynamic process leading to mutual contempt between political groups. The article shows how indignation and its dynamic processes have helped unleash backlash politics in the United States.

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