Superconducting Resonators: Decrease of Q-Factor at High Accelerating Field

2014 ◽  
Vol 9 (2) ◽  
pp. 22-35
Author(s):  
Aleksandr Dzyuba ◽  
Andrey Arzhannikov
Keyword(s):  
Radio Frequency ◽  
Research Methods ◽  
Q Factor ◽  
Chemical Research ◽  
Superconducting Resonators ◽  
Alternative Processing ◽  
Physico Chemical ◽  
Superconducting Radio Frequency ◽  
Processing Steps

Results combining efforts of different groups on investigation of losses in superconducting radio frequency cavities made of niobium are presented. Peculiarities of such losses and of their remedies are considered for dissipation at high accelerating voltages. The main results of RF tests as well as main experiments conducted via physico-chemical research methods on samples are discussed. The role of different type of defects on losses is presented. The candidate mechanisms for dissipation are considered based on exhibited results. As a conclusion the prediction is made on possible alternative processing steps for improvement of cost, time and safety efficiency of current technological procedures

scholarly journals Comprehensive Study of the Physical and Chemical Properties of Phosphorus Sludge and Cottrell Dust

2021 ◽  
Author(s):  
Ulzhalgas Nazarbek ◽  
Uilesbek Besterekov ◽  
Perizat Abdurazova ◽  
Saule Nazarbekova ◽  
Yerkebulan Raiymbekov
Keyword(s):  
Research Methods ◽  
Chemical Properties ◽  
Mineral Fertilizers ◽  
Physical And Chemical Properties ◽  
Chemical Research ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
Instrumental Methods ◽  
And Chemical Properties ◽  
Comprehensive Study

The article presents the results of physico-chemical research of waste from the phosphorus industry – phosphorus sludge and cottrell dust. The reliability of the experimental results was ensured by the use of generally recognized research methods, as well as reliable physico-chemical and instrumental methods of analysis. The results of the experiment prove the suitability of these types of waste for the production of mineral fertilizers. This, in turn, will make it possible to improve the environmental situation in the southern region of Kazakhstan.

Activation of cytochrome c to a peroxidase compound I-type intermediate by H2O2: relevance to redox signalling in apoptosis

2004 ◽  
Vol 71 ◽  
pp. 97-106 ◽  
Author(s):  
Mark Burkitt ◽  
Clare Jones ◽  
Andrew Lawrence ◽  
Peter Wardman
Keyword(s):  
Cytochrome C ◽  
Hydroxyl Radical ◽  
Redox Regulation ◽  
Chemotherapeutic Agents ◽  
Tyrosyl Radical ◽  
Compound I ◽  
Definitive Evidence ◽  
Enhanced Production ◽  
Physico Chemical

The release of cytochrome c from mitochondria during apoptosis results in the enhanced production of superoxide radicals, which are converted to H2O2 by Mn-superoxide dismutase. We have been concerned with the role of cytochrome c/H2O2 in the induction of oxidative stress during apoptosis. Our initial studies showed that cytochrome c is a potent catalyst of 2′,7′-dichlorofluorescin oxidation, thereby explaining the increased rate of production of the fluorophore 2′,7′-dichlorofluorescein in apoptotic cells. Although it has been speculated that the oxidizing species may be a ferryl-haem intermediate, no definitive evidence for the formation of such a species has been reported. Alternatively, it is possible that the hydroxyl radical may be generated, as seen in the reaction of certain iron chelates with H2O2. By examining the effects of radical scavengers on 2′,7′-dichlorofluorescin oxidation by cytochrome c/H2O2, together with complementary EPR studies, we have demonstrated that the hydroxyl radical is not generated. Our findings point, instead, to the formation of a peroxidase compound I species, with one oxidizing equivalent present as an oxo-ferryl haem intermediate and the other as the tyrosyl radical identified by Barr and colleagues [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503]. Studies with spin traps indicated that the oxo-ferryl haem is the active oxidant. These findings provide a physico-chemical basis for the redox changes that occur during apoptosis. Excessive changes (possibly catalysed by cytochrome c) may have implications for the redox regulation of cell death, including the sensitivity of tumour cells to chemotherapeutic agents.

Moving Beyond Themes

2013 ◽  
Vol 2 (2) ◽  
pp. 213-227 ◽  
Author(s):  
Kristen Lucas ◽  
Suzy D’Enbeau
Keyword(s):  
Qualitative Research ◽  
Research Methods ◽  
Qualitative Research Methods

Teaching novice qualitative researchers how to move beyond first-cycle themes is a challenging endeavor. In this essay, we articulate four harmful habits that tend to impede our success: moving too quickly, privileging product over process, providing cursory coverage of analytic technique and artistry, and overlooking the role of synthesis in qualitative research. As a step toward replacing harmful habits with more healthy ones, we offer a number of practical suggestions for reimagining the qualitative research methods curriculum.

Quantitative and Qualitative Methods of Studying the Processes of Socialization of a Modern Teenager

2020 ◽  
pp. 102-109
Author(s):  
Svetlana Alekseevna Raschetina ◽  
Keyword(s):  
Research Methods ◽  
Interpersonal Relations ◽  
Internet Communication ◽  
Socialization Process ◽  
Wide Range ◽  
The Family ◽  
Modern Family ◽  
Making Friends ◽  
Main Support

Relevance and problem statement. Modern unstable society is characterized by narrowing the boundaries of controlled socialization and expanding the boundaries of spontaneous socialization of a teenager based on his immersion in the question arises about the importance of the family in the process of socialization of a teenager in the conditions of expanding the space of socialization. There is a need to study the role of the family in this process, to search, develop and test research methods that allow us to reveal the phenomenon of socialization from the side of its value characteristics. The purpose and methodology of the study: to identify the possibilities of a systematic and anthropological methodology for studying the role of the family in the process of socialization of adolescents in modern conditions, testing research methods: photo research on the topic “Ego – I” (author of the German sociologist H. Abels), profile update reflexive processes (by S. A. Raschetina). Materials and results of the study. The study showed that for all the problems that exist in the family of the perestroika era and in the modern family, it acts for a teenager as a value and the first (main) support in the processes of socialization. The positions well known in psychology about the importance of interpersonal relations in adolescence for the formation of attitudes towards oneself as the basis of socialization are confirmed. Today, the frontiers of making friends have expanded enormously on the basis of Internet communication. The types of activities of interest to a teenager (traditional and new ones related to digitalization) are the third pillar of socialization. Conclusion. The “Ego – I” method of photo research has a wide range of possibilities for quantitative and qualitative analysis of the socialization process to identify the value Pillars of this process.

THYROID STIMULATORS AND THYROID STIMULATION

1971 ◽  
Vol 66 (3) ◽  
pp. 558-576 ◽  
Author(s):  
Gerald Burke
Keyword(s):  
Regulatory System ◽  
Control Site ◽  
Thyroid Cell ◽  
Primary Control ◽  
Physico Chemical ◽  
Site Of Action ◽  
Long Acting

ABSTRACT A long-acting thyroid stimulator (LATS), distinct from pituitary thyrotrophin (TSH), is found in the serum of some patients with Graves' disease. Despite the marked physico-chemical and immunologic differences between the two stimulators, both in vivo and in vitro studies indicate that LATS and TSH act on the same thyroidal site(s) and that such stimulation does not require penetration of the thyroid cell. Although resorption of colloid and secretion of thyroid hormone are early responses to both TSH and LATS, available evidence reveals no basic metabolic pathway which must be activated by these hormones in order for iodination reactions to occur. Cyclic 3′, 5′-AMP appears to mediate TSH and LATS effects on iodination reactions but the role of this compound in activating thyroidal intermediary metabolism is less clear. Based on the evidence reviewed herein, it is suggested that the primary site of action of thyroid stimulators is at the cell membrane and that beyond the(se) primary control site(s), there exists a multifaceted regulatory system for thyroid hormonogenesis and cell growth.

The Influence of Benthic Biota on Copper Speciation and Distribution in Freshwater-Sediment Systems

1981 ◽  
Vol 16 (1) ◽  
pp. 45-58 ◽  
Author(s):  
G. Krantzberg ◽  
P.M. Stokes
Keyword(s):  
Freshwater Sediment ◽  
Benthic Macroinvertebrate ◽  
Macroinvertebrate Communities ◽  
Copper Species ◽  
Copper Speciation ◽  
Physico Chemical ◽  
Macro Benthos

Abstract An investigation was made of the effects exerted by benthic macroinvertebrate communities on copper speciation in sediments from a lake which is becoming acidified. In laboratory microcosms, benthic macroinvertebrate communities stimulated the flux of copper from sediment to water. The presence of the macro-benthos resulted in a redistribution of physico-chemical copper species within the sediment with a transfer from more strongly complexed forms (HC1 extractable) to adsorbed and cation exchangeable forms (MgCl2 extractable). The role of bio-turbation in copper transformations is discussed.

A Brief Statement on the Future of Public Scholarship and the Research Methods Landscape

2019 ◽  
pp. 700-707
Author(s):  
Patricia Leavy
Keyword(s):  
Research Methods ◽  
Teaching Practices ◽  
Knowledge Building ◽  
Research Community ◽  
The State ◽  
Public Scholarship ◽  
Institutional Structures ◽  
The Future ◽  
Book Editor

The book editor offers some final comments about the state of the field and promise for the future. Leavy suggests researchers consider using the language of “shapes” to talk about the forms their research takes and to highlight the ongoing role of the research community in shaping knowledge-building practices. She reviews the challenges and rewards of taking your work public. Leavy concludes by noting that institutional structures need to evolve their rewards criteria in order to meet the demands of practicing contemporary research and suggests that professors update their teaching practices to bring the audiences of research into the forefront of discussions of methodology.

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