Ce:LaB3O6 glass for high-resolution radiation dosimetry

Ce:LaB3O6 (LBO) glass, whose constituents are abundant elements and fabrication is easy and cheap, is found to be a promising thermoluminescence (TL) dosimeter. This is originally achieved by CeF3 doping and melting under a reducing atmosphere, with the optimum concentration of 0.1% (quantum efficiency = 66%). The corresponding Ce interatomic distance is ~ 4 nm, below which concentration quenching occurs via Ce dipole-dipole interaction, as elucidated experimentally by Dexter’s theory. Ce:LBO exhibits a good dose resolution, with a linear dependence covering five orders of magnitude on both irradiation-dose and TL-response. Furthermore, it can be cyclically irradiated and read without degradation.

Dependence of the Xe flash lamps’ UV radiation efficiency on the volumetric power density of the discharge

The study results of the peak and average electrical volumetric power density influence on the radiation efficiency and brightness temperature in the 200–300 nm bactericidal spectrum range are presented. A linear dependence of the radiation efficiency change in the 5.1–8.4 % range was obtained with the average volumetric power density increase from 177 to 390 kW/cm3. The brightness temperature dependence in the specified spectral region on the peak volumetric power density is a logarithmic character with decreasing growth rate when approaching 9 kK. This effect can be associated with both radiation blocking by vaporized quartz fumes and with UV light shielding by outer plasma layers

Radical Complexity

This is an informal and sketchy review of five topical, somewhat unrelated subjects in quantitative finance and econophysics: (i) models of price changes; (ii) linear correlations and random matrix theory; (iii) non-linear dependence copulas; (iv) high-frequency trading and market stability; and finally—but perhaps most importantly—(v) “radical complexity” that prompts a scenario-based approach to macroeconomics heavily relying on Agent-Based Models. Some open questions and future research directions are outlined.

INFLUENCE OF THE CONTENT OF PHENOLIC COMPOUNDS ON THE TASTE CHARACTERISTICS OF FOOD CARROTS

Исследовано изменение содержания фенольных соединений при хранении корнеплодов столовой моркови 14 сортов, перерабатываемых на предприятиях Беларуси. Отбор образцов моркови осуществляли из специализированных овощехранилищ 1 раз в месяц в течение 5 мес. Содержание фенольных соединений определяли по методике, адаптированной авторами для матрицы моркови, на основе реакции окисления фенольных соединений реактивом Фолина–Чокальтеу и последующей фотометрией при длине волны 765 нм. Общую сумму фенольных соединений определяли в пересчете на феруловую кислоту. Установлено, что наименьшее количество фенольных соединений содержали свежеубранные корнеплоды моркови (2,10–7,21 мг/100 г в зависимости от сорта). После 5 мес хранения концентрация водорастворимых фенольных соединений в корнеплодах в зависимости от сорта составила 16,07–40,78 мг/100 г, что превысило исходное содержание в 2,9–7,5 раза. Содержание фенольных соединений в корнеплодах моркови повышалось неравномерно в течение хранения. В 6 образцах рост характеризовался линейной зависимостью с коэффициентами корреляции 0,95 Ј R2 Ј 0,99, в 8 – экспоненциальной (0,92 Ј R2 Ј 0,99). Ощутимая горечь во вкусе появилась во всех образцах корнеплодов моркови после 4 мес хранения. В 11 образцах наблюдалась корреляция 0,91 между показателем ощущения горечи и содержанием фенольных соединений. По совокупности оцененных показателей наиболее предпочтительными для переработки на сок прямого отжима являются сорта столовой моркови Витаминная-6, Белградо, Лявониха, Монанта, Нантская 4. The change in the content of phenolic compounds during the storage of table carrot root crops of 14 varieties processed at Belarusian enterprises has been investigated. Carrot samples were taken from specialized vegetable storages once a month for 5 months. The content of phenolic compounds was determined by the method adapted by us for the carrot matrix, based on the oxidation reaction of phenolic compounds with the Folin–Chocalteu reagent and subsequent photometry at a wavelength of 765 nm. The total amount of phenolic compounds is determined in terms of ferulic acid. It was found that freshly harvested carrot roots contained the least amount of phenolic compounds (2,10–7,21 mg/100 g, depending on the variety). After 5 months of storage, the concentration of water-soluble phenolic compounds in root crops, depending on the variety, was 16,07–40,78 mg/100 g, which exceeded the initial content by 2,9–7,5 times. The content of phenolic compounds in carrot roots increased unevenly during storage. In 6 samples, the growth was characterized by a linear dependence with correlation coefficients of 0,95 Ј R2 Ј 0,99, in 8 – exponential (0,92 Ј R2 Ј 0,99). Palpable bitterness in taste appeared in all samples of carrot root crops after 4 months of storage. A correlation of 0,91 between the feeling of bitterness and the content of phenolic compounds was observed in 11 samples. According to the totality of the estimated indicators, the varieties of food carrots Vitaminnaya-6, Belgrado, Lyavonikha, Monanta, Nanta 4 are. most preferred for processing into juice of direct extraction.

Adaptive market hypothesis: An empirical analysis of the Wine Market

We test the nature of weak form informational efficiency present in the wine market using daily return of LIV-EX 50 index from 1/1/2010 to 12/6/2020. First, we employ a number of statistical tests including variance ratio tests, tests for linear and non-linear dependence and Hurst coefficient. The tests are applied on the full dataset and on four non overlapping sub-samples of equal length. The variance ratio tests provide a mixed regarding informational efficiency. Evidence of non-linear dependence in the return series was found. The Hurst coefficient values confirm the presence of long run persistence in the wine market. Based on the mixed evidence, we test the possibility of adaptive nature of the wine market. We employ the newly proposed Adaptive Index (AI) to quantify the degree of information inefficiency in the wine market at any instance. Our results confirm that wine market is adaptive and periodically shifts between states of efficiency and inefficiency. The wine market is found to be relatively free from the Covid-19 induced shock and the safe haven property of wine is thus confirmed. Finally, impact of various macroeconomic and financial events on wine market efficiency is identified by using AI.

Diversity, dependence and independence

We propose a very general, unifying framework for the concepts of dependence and independence. For this purpose, we introduce the notion of diversity rank. By means of this diversity rank we identify total determination with the inability to create more diversity, and independence with the presence of maximum diversity. We show that our theory of dependence and independence covers a variety of dependence concepts, for example the seemingly unrelated concepts of linear dependence in algebra and dependence of variables in logic.

Cuts for two-body decays at colliders

Fixed-order perturbative calculations of fiducial cross sections for two-body decay processes at colliders show disturbing sensitivity to unphysically low momentum scales and, in the case of H → γγ in gluon fusion, poor convergence. Such problems have their origins in an interplay between the behaviour of standard experimental cuts at small transverse momenta (pt) and logarithmic perturbative contributions. We illustrate how this interplay leads to a factorially divergent structure in the perturbative series that sets in already from the first orders. We propose simple modifications of fiducial cuts to eliminate their key incriminating characteristic, a linear dependence of the acceptance on the Higgs or Z-boson pt, replacing it with quadratic dependence. This brings major improvements in the behaviour of the perturbative expansion. More elaborate cuts can achieve an acceptance that is independent of the Higgs pt at low pt, with a variety of consequent advantages.

Study on Mechanisms of Photon-Induced Material Removal on Silicon at Atomic and Close-to-Atomic Scale

This paper presents a new approach for material removal on silicon at atomic and close-to-atomic scale assisted by photons. The corresponding mechanisms are also investigated. The proposed approach consists of two sequential steps: surface modification and photon irradiation. The back bonds of silicon atoms are first weakened by the chemisorption of chlorine and then broken by photon energy, leading to the desorption of chlorinated silicon. The mechanisms of photon-induced desorption of chlorinated silicon, i.e., SiCl2 and SiCl, are explained by two models: the Menzel–Gomer–Redhead (MGR) and Antoniewicz models. The desorption probability associated with the two models is numerically calculated by solving the Liouville–von Neumann equations for open quantum systems. The calculation accuracy is verified by comparison with the results in literatures in the case of the NO/Pt (111) system. The calculation method is then applied to the cases of SiCl2/Si and SiCl/Si systems. The results show that the value of desorption probability first increases dramatically and then saturates to a stable value within hundreds of femtoseconds after excitation. The desorption probability shows a super-linear dependence on the lifetime of excited states.

Mixed initial-boundary value problems describing motions of Maxwell fluids with linear dependence of viscosity on the pressure

Some mixed initial-boundary value problems are analytically studied. They correspond to unsteady motions of the incompressible upper-convected Maxwell (IUCM) fluids with linear dependence of viscosity on the pressure between infinite horizontal parallel plates. The fluid motion is generated by the upper plate that applies time-dependent shear stresses to the fluid. Exact solutions are established for the dimensionless velocity and nontrivial shear stress fields using a suitable change of the spatial variable and the Laplace transform technique. They are presented as sum of the steady-state and transient components and are used to determine the required time to reach the permanent state. Comparisons between exact and numerical solutions indicate an excellent agreement. Analytical solutions for the unsteady motion of the same fluids induced by an exponential shear stress on the boundary are obtained as limiting cases of the general solutions. Moreover, the steady-state solutions corresponding to the ordinary IUCM fluids performing the initial motions are provided by means of asymptotic approximations of standard Bessel functions. Finally, spatial variation of starting solutions and the influence of physical parameters on the fluid motion are graphically underlined and discussed.

About Some Questions of the Organization of Work of Workers in the Conditions of Exposure to Ionizing Radiation

The article discusses the need to make changes to the regulatory documents that classify harmful and (or) dangerous production factors that stimulate and regulate the work of workers under the influence of ionizing radiation based on the concept of a linear dependence of the risk of stochastic effects on the received dose.