scholarly journals Structural changes induced in crystals by the photocyclization and high pressure

2014 ◽  
Vol 70 (a1) ◽  
pp. C770-C770
Author(s):  
Julia Bakowicz ◽  
Ilona Turowska-Tyrk
Keyword(s):  
High Pressure ◽  
Structural Changes ◽  
Photochemical Reactions ◽  
Reaction Centre ◽  
University Of Technology ◽  
European Social Fund ◽  
Science Centre ◽  
Social Fund ◽  
And Behavior

Photo-induced processes in crystals studied by means of X-ray structure analysis are the main subject of our interest. In particular, we monitor structural changes brought about by photochemical reactions. Nowadays, we have started to study influence of high pressure on them. In this poster, the results on monitoring structural changes in crystals of 2-tert-butylphenylphenylmethanone proceeding during the photocyclization reaction at ambient and high pressure will be presented. The studies demanded determination of structures of the pure reactant, pure product and many partly reacted crystals (Fig. 1) and were carried out at 0.1 MPa and 0.55, 1.27 and 1.50 GPa. Variations in the cell constants, geometry of the reaction centre and behavior of molecules during the phototransformation at various pressures will be presented. Several differences and similarities were observed. The studies provided knowledge on the path of the reaction in crystals and the influence of external factors, i.e. pressure, on it. Acknowledgments: The work was carried out within the grant 2011/01/D/ST5/02834 financed by the National Science Centre (Poland) and the fellowship co-financed by European Union within European Social Fund (Wroclaw University of Technology, Poland).

scholarly journals An assessment of the effectiveness of support for university programs from the human capital operational program in years 2013-2015 in the development of students competences in entrepreneurship

2018 ◽  
pp. 75-80
Author(s):  
Kinga Koroniejko
Keyword(s):  
Critical Analysis ◽  
Organizational Innovation ◽  
Field Education ◽  
University Of Technology ◽  
European Social Fund ◽  
Social Fund ◽  
Operational Program ◽  
Student Competencies ◽  
Development Of Students

The article presents the ways of support from European funds in the development of student competencies and organizational innovation in the field education. It is based on a case study of the project ‘Inżynieria materiałowa – inżynieria przyszłości’ (Material engineering – engineering of the future’), financed by the European Social Fund in Poland. The project was implemented at the Faculty of Mechanical Engineering of the Cracow University of Technology in the years 2012-15. The research methods used are critical analysis of literature sources, surveys and a case study of the project mentioned above.

Determination of the intensity of polychromatic radiation in the reaction compartment as a function of wavenumber

1991 ◽  
Vol 56 (6) ◽  
pp. 1173-1179 ◽  
Author(s):  
Radim Hrdina ◽  
Igor Čepčiansky ◽  
Hana Bittová
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
High Pressure ◽  
Emission Spectrum ◽  
Photochemical Reactions ◽  
Tabular Form ◽  
Mercury Lamp ◽  
Kinetics Of ◽  
Polychromatic Radiation

A procedure is suggested for studying the kinetics of photochemical reactions using excitation with polychromatic radiation, where the wavenumber dependence of the intensity of the polychromatic radiation entering the reaction compartment must be known. The observed relative intensities of the polychromatic source are calibrated by ferrioxalate actinometry, selected parts of the emission spectrum being eliminated by insertion of filters. The relative intensities of an HBO 200 high-pressure mercury lamp were measured. For the sake of brevity, the experimental data were fitted by a mathematical model (a polynominal), and only the parameters of the polynomial are presented in a tabular form.

Formation of defects in implanted hipox-structures

1992 ◽  
Vol 50 (2) ◽  
pp. 1406-1407
Author(s):  
Peter Pegler ◽  
N. David Theodore ◽  
Ming Pan
Keyword(s):  
High Pressure ◽  
Cross Section ◽  
Semiconductor Devices ◽  
Silicon Substrates ◽  
Processing Conditions ◽  
Pressure Oxidation ◽  
Deep Trench ◽  
Local Oxidation ◽  
Trench Isolation ◽  
And Behavior

High-pressure oxidation of silicon (HIPOX) is one of various techniques used for electrical-isolation of semiconductor-devices on silicon substrates. Other techniques have included local-oxidation of silicon (LOCOS), poly-buffered LOCOS, deep-trench isolation and separation of silicon by implanted oxygen (SIMOX). Reliable use of HIPOX for device-isolation requires an understanding of the behavior of the materials and structures being used and their interactions under different processing conditions. The effect of HIPOX-related stresses in the structures is of interest because structuraldefects, if formed, could electrically degrade devices.This investigation was performed to study the origin and behavior of defects in recessed HIPOX (RHIPOX) structures. The structures were exposed to a boron implant. Samples consisted of (i) RHlPOX'ed strip exposed to a boron implant, (ii) recessed strip prior to HIPOX, but exposed to a boron implant, (iii) test-pad prior to HIPOX, (iv) HIPOX'ed region away from R-HIPOX edge. Cross-section TEM specimens were prepared in the <110> substrate-geometry.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Studies on the Behavior Some Paints in Electro-insulating Fluid Based on Vegetable Esters

2018 ◽  
Vol 69 (5) ◽  
pp. 1139-1144
Author(s):  
Iosif Lingvay ◽  
Adriana Mariana Bors ◽  
Livia Carmen Ungureanu ◽  
Valerica Stanoi ◽  
Traian Rus
Keyword(s):  
Structural Changes ◽  
Oxidation Processes ◽  
High Oleic ◽  
Painting Materials ◽  
Insulating Paper ◽  
Different Types ◽  
Mechanism And Kinetics ◽  
Kinetics Of ◽  
Natural Ester

For the purpose of using three different types of painting materials for the inner protection of the transformer vats, their behavior was studied under actual conditions of operation in the transformer (thermal stress in electro-insulating fluid based on the natural ester in contact with copper for electro-technical use and electro-insulating paper). By comparing determination of the content in furans products (HPLC technique) and gases formed (by gas-chromatography) in the electro-insulating fluid (natural ester with high oleic content) thermally aged at 130 �C to 1000 hours in closed glass vessels, it have been found that the presence the investigated painting materials lead to a change in the mechanism and kinetics of the thermo-oxidation processes. These changes are supported by oxygen dissolved in oil, what leads to decrease both to gases formation CO2, CO, H2, CH4, C2H4 and C2H6) and furans products (5-HMF, 2-FOL, 2 -FAL and 2-ACF). The painting materials investigated during the heat treatment applied did not suffer any remarkable structural changes affecting their functionality in the electro-insulating fluid based on vegetable esters.

LC-MS/MS Method Development and Validation for the Determination of Ilexsaponin A1 and Its Application in Intestinal Bacterial Metabolic Study

2020 ◽  
Vol 16 (6) ◽  
pp. 774-781
Author(s):  
Liang Wu ◽  
An Kang ◽  
Yujie Lin ◽  
Chenxiao Shan ◽  
Zhu Zhou ◽  
...  
Keyword(s):  
Method Development ◽  
Ischemia Reperfusion ◽  
Scientific Evidence ◽  
Potential Effect ◽  
Bacterial Strains ◽  
Metabolic Potential ◽  
Bifidobacterium Adolescentis ◽  
Metabolic Behavior ◽  
And Behavior

Background: Ilexsaponin A1, one of the most representative triterpene saponin components in the roots of I. pubescens, showed its effects in anticoagulation and antithrombosis, attenuating ischemia-reperfusion-induced myocardial, angiogenesis and inhibiting phosphodiesterase. Objective: Reveal the key intestinal bacterial strains responsible for ilexsaponin A1 metabolism, and clarify their metabolic behavior. Methods: An accurate and sensitive LC-MS/MS method for the determination of “ilexsaponin A1 in General Anaerobic Medium (GAM) broth” was established and systematically validated. Then it was applied to screen and study the metabolic potential of the intestinal bacterial strains in an anaerobic incubation system. Results: Quantitation of ilexsaponin A1 could be performed within an analytical run time of 14.5 min, in the linear range of 2 - 2000 ng/ml. Enterobacter sakazakii, Bifidobacterium breve, Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Bifidobacterium angulatum were identified to have a potential effect to metabolize ilexsaponin A1 to different extents; and further bacterial metabolic studies were performed to clarify their metabolic capacity and behavior. Conclusion: This paper contributes to a better understanding of the intestinal bacterial metabolism of ilexsaponin A1 and provides scientific evidence for its clinical application. Additionally, the importance of intestinal bacterial strains in the disposition of natural products was also highlighted.

scholarly journals New high-pressure phases of Fe7N3 and Fe7C3 stable at Earth's core conditions: evidences for carbon–nitrogen isomorphism in Fe-compounds

RSC Advances ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 3577-3581 ◽  
Author(s):  
Nursultan Sagatov ◽  
Pavel N. Gavryushkin ◽  
Talgat M. Inerbaev ◽  
Konstantin D. Litasov
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Ab Initio ◽  
Structure Prediction ◽  
Harmonic Approximation ◽  
Crystal Structure Prediction ◽  
Earth’S Core ◽  
Earth's Core ◽  
Core Conditions

We carried out ab initio calculations on the crystal structure prediction and determination of P–T diagrams within the quasi-harmonic approximation for Fe7N3 and Fe7C3.

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