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•The classification of surface nitrates currently used by consensus is misleading.•Nitrates on ceria, thought to be monodentate, are actually tridentate.•Isotopic exchange with 18O ...helps distinguishing different nitrate coordination.•Bidentate nitrates on ceria are bridging and chelating simultaneously.•Bi/tridentate nitrates on ceria are converted to monodentate in presence of water.
Nitrates formed on ceria surface were investigated by FTIR spectroscopy and DFT methods. Isotope labelling (15N, 18O) was utilized to strengthen the conclusions. We found that the structures usually associated with monodentate nitrates (IR bands at ca. 1460, 1300 and 1030 cm−1), although bound to surface most strongly via one oxygen atom, are tridentate nitrates with C2v symmetry. The bidentate nitrates, as a rule, simultaneously bridge and chelate cerium cations. The spectral difference between these species is due to the binding geometry and symmetry reduction. An experimental approach is proposed to distinguish between different nitrate coordination. It is based on the split of the higher frequency IR band (1650–1450 cm−1) upon partial exchange with 18O: one new band appears for bidentate nitrates and two new bands for monodentate and the observed tridentate nitrates.
The testing was conducted during the winter semester of the academic year 2016/2017. The study contingent consists of 69 female students from the Faculty of Agriculture, the Faculty of Veterinary ...Medicine and the Faculty of Economics at the Trakia University of Stara Zagora. They were divided into two groups - experimental and control. The purpose of this study is to determine the effect of circular workouts on the level of physical quality of muscle strength of Traкia University female students. To achieve our goal, we set out the following tasks - researching literature sources, developing and testing a specialized fitness model, developing a test battery, processing and analyzing the data from the testing. The following methods were used - pedagogical experiment, testing, variational analysis, comparative analysis, graphical method. A test battery has been developed. The results and analysis show that the experiment is successful and the developed fitness program is effective. Effectiveness of developed authors fitness model, based on circular workout, as part of the overall fitness training of the female students, for priority development of motor quality “strength” is experimentally justified.
The purpose of the present study is to determine the influence of circular exercises on the cardiovascular and respiratory systems of Trakia's University female students. To achieve this goal the ...following methods are used: testing, pedagogical experiment, variation analysis, comparative analysis, graphic analysis. 69 female students are the contingent of the study with an average age of 20.04 years old from the first and second school year, studying in three different faculties of the Trakia University - Faculty of Economics, Faculty of Agriculture and Faculty of Veterinary Medicine. They were divided into two groups. The experimental group of 36 female students - with this group was hold circuit trainings twice a week in the duration of 30 weeks. On the basis of the conducted research, in order to increase the efficiency of the fitness training by applying a specialized training fitness model intended for the students, and the analyzes made it can be concluded: The effectiveness of the author's fitness model, based on circular training, as part of the overall fitness training of the students for strengthening the cardiovascular and the respiratory systems of the students, are experimentally substantiated.
The purpose of the present study is to establish the factor relationships between morpho-functional parameters and physical qualities, muscle strength and endurance due to the application of a ...specialized fitness model. To achieve this goal we the following tasks are set: research of literature resources; development and testing of a specialized fitness model; development of a test battery; processing and analyzing the data from the conducted testing. Research methods - pedagogical experiment, testing, factor analysis, graphical analysis. The contingent of the study are 34 students from the Trakia University. The students are on average 20.04 years old. The results and their analysis show that in the applied fitness model there is a decrease in the number of the main factors in the factor structure of the morpho-functional indicators and the observed motor functions; the increase in the influence of the first main factor in the second study explains the higher percentage of the cumulative variance. This leads to structural changes in the content of the main factors; changes the influence of factors, which after the experiment increases the influence of endurance due to the composition of body weight; the force factors retain approximately the same weight in the second study.
It is shown that the Differential decay curve method applied to analyze coincidence Doppler-shift attenuation lifetime measurements with a gate on the shifted component of a directly feeding feeding ...transition is characterized by stable results within scaling variations of the stopping powers of up to 15% at least. This is due to cancellation in the formula used for the lifetime determination while when using the traditional data analysis methods the imprecision in the stopping powers cannot be surrounded.
Functional near-infrared spectroscopy (fNIRS) is an optical imaging method that is used to noninvasively measure cerebral hemoglobin concentration changes induced by brain activation. Using ...structural guidance in fNIRS research enhances interpretation of results and facilitates making comparisons between studies. AtlasViewer is an open-source software package we have developed that incorporates multiple spatial registration tools to enable structural guidance in the interpretation of fNIRS studies. We introduce the reader to the layout of the AtlasViewer graphical user interface, the folder structure, and user files required in the creation of fNIRS probes containing sources and detectors registered to desired locations on the head, evaluating probe fabrication error and intersubject probe placement variability, and different procedures for estimating measurement sensitivity to different brain regions as well as image reconstruction performance. Further, we detail how AtlasViewer provides a generic head atlas for guiding interpretation of fNIRS results, but also permits users to provide subject-specific head anatomies to interpret their results. We anticipate that AtlasViewer will be a valuable tool in improving the anatomical interpretation of fNIRS studies.
A qualitative game describes a situation in which antagonistic players strive to keep the evolutions of their state variables in predetermined constraint sets. We argue that a qualitative game model ...is a suitable mathematical representation of the struggle between a domestic central bank of a small open economy and a foreign central bank of a large economy to maintain their respective state variables within an acceptable band regardless of the other player’s choices. The actions of the foreign central bank affect the domestic exchange rate and, hence, domestic inflation, output gap and interest rate. However, these actions do not necessarily aim to destabilise the small open economy, nor do they take into account the state of the latter. The domestic bank’s problem, therefore, is similar to that of a game against nature. We refer to this type of qualitative game as a nuisance-agent game (or NA-game). We use viability theory to derive satisficing rules (in the sense of Simon) of nominal interest-rate adjustments for the domestic central bank of a small open economy in a qualitative NA-game against the foreign central bank.
The paper presents the design and experimental evaluation of two alternative μ-controllers for robust vertical stabilisation of a two-wheeled self-balancing robot. The controllers design is based on ...models derived by identification from closed-loop experimental data. In the first design, a signal-based uncertainty representation obtained directly from the identification procedure is used, which leads to a controller of order 29. In the second design the signal uncertainty is approximated by an input multiplicative uncertainty, which leads to a controller of order 50, subsequently reduced to 30. The performance of the two μ-controllers is compared with the performance of a conventional linear quadratic controller with 17th-order Kalman filter. A proportional-integral controller of the rotational motion around the vertical axis is implemented as well. The control code is generated using Simulink® controller models and is embedded in a digital signal processor. Results from the simulation of the closed-loop system as well as experimental results obtained during the real-time implementation of the designed controllers are given. The theoretical investigation and experimental results confirm that the closed-loop system achieves robust performance in respect to the uncertainties related to the identified robot model.
Crystalline thin films of BiTeSe were deposited onto well cleaned glass substrates (BK7 type) by the vacuum thermal evaporation technique at a pressure of 10−3 Pa. Bulk samples were used as targets ...to evaporate the corresponding films. The internal microstructure of bulk samples and films were characterized by x-ray diffraction (XRD). Identifications of the microstructure and the surface morphology of the bulk and thin film samples were determined using scanning electron microscopy (SEM). Powder of the bulk alloys and the thin films of our products were observed to be polycrystalline in the form of hexagonal Bi2Se3 and Bi2Te3 structure. The material characteristic power factor of 74 μ W/mK2 was observed as the maximum value of power factor obtained in our study, and that was for Bi2Te3 near room temperature. The dimensionless figure of merit (ZT) was estimated based on Seebeck coefficient and electrical conductivity measurements alongside with thermal conductivity estimations. ZT values of Bi2Se3 and Bi2Se1.5Te1.5 were significantly enhanced as temperature increased, whilst, ZT of Bi2Te3 exhibited an opposite behavior. A mechanical stress test was performed in order to investigate the suitability of our films for thermoelectric modulus.
•Thin films of BiTeSe alloys were deposited by the vacuum thermal evaporation technique.•Bulk alloys and thin films of our products are polycrystalline in the form of hexagonal Bi2Se3 and Bi2Te3 structure.•Power factor of 74 μ W/mK2 was observed as the maximum value for Bi2Te3 near room temperature.•Mechanical stress test was performed in order to investigate the suitability of our films for thermoelectric modulus.
Reliable data on physical fitness and determination of the functional state of the body reflect the level of physical capabilities and the level of development of motor skills. Objective: ...Determination of individual physiometric indicators in students. Contingent: 130 female students of Trakia University. The average value of the vital capacity in the studied students is 3, 60, and vital indicator 61,61. With the left and right hand dynamometer, mean right hand values of 15,46 kg were found, and left - 12,76 kg. Force strength is set at 63,42kg. Conclusion: The relative share of students with low values of the vital capacity is high, the values for dynamometry force are also low; there is a disproportion between good physical development due to acceleration factors and recorded retention or deterioration of physical capacity.
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