Plasma Flow and Temperature in a Gliding Reactor with Different Electrode Configurations

This paper deals with the plasma flow shape depending on the electrode form of a gliding discharge plasma-chemical reactor, and with the temperature distribution along the direction of the plasma flow in one specific electrode form. The shape of the electrodes and their mutual position has a significant influence on the design of a gliding discharge reactor and its applications. It is crucial to know the temperature distribution in the reactor’s chamber design and discharge application. Three configurations with model shapes of wire electrodes were therefore tested (low-divergent, circular, high-divergent) and the plasma flow was described. The experiments were performed in air at atmospheric pressure and at room temperature. In order to map the reactive plasma region of the flow we investigated the visible spectral lines that were emitted. The gas temperature was measured using an infrared camera

Connection between electrodes shape and plasma flow of the gliding discharge

Contribution deals with form of electrodes and corresponding shape of plasma flow in the gliding discharge reactor. Gliding discharge sustained in air at atmospheric pressure and room temperature. There were studied three elemental electrodes configuration. Plasma was investigated by means of its visible spectral lines for identification of the most reactive plasma region in the flow. Results can be helpful in shaping of the gliding discharge reactor ionized gas regionДосліджується питання відповідності форми електродів і потока плазми в реакторі з ковзаючим розрядом. Ковзаючий розряд підтримувався в повітрі при атмосферному тиску і кімнатній температурі. Було досліджено три основні конфігурації електродів. Плазма досліджувалася за допомогою видимих спектральних ліній для виявлення найбільш активних областей у потоці плазми. Результати можуть бути корисні для створення реактора з ковзаючим розрядом у іонізованій газовій області.Исследуется вопрос соответствия формы электродов и потока плазмы в реакторе со скользящим разрядом. Скользящий разряд поддерживался в воздухе при атмосферном давлении и комнатной температуре. Были исследованы три основные конфигурации электродов. Плазма исследовалась с помощью видимых спектральных линий для выявления наиболее активных областей в потоке плазмы. Результаты могут быть полезны для создания реактора со скользящим разрядом в ионизованной газовой области

Polyester fabric modified with atmospheric dielectric barrier discharge supplied with voltage of different frequencies

Final characteristics of polymers are the compromise between wanted surface and bulk properties. Important change of the polymer use-value can be caused by modification of characteristics of its upper structural units (i.e. in region under the surface deep some tens of nanometers). These changes – and modification – can be performed i. a. by treatment with the “cold” plasma and moreover with low costs and minimum environmental impact. Modification of polymer surface characteristics may proceed during functionalization, when plasma particles react with polymer surface molecules and new chemical functional groups are formed on polymer surface. These chemical reactions can be influenced with composition of atmosphere in the plasma reactor, e.g. application of oxygen plasma leads to polymer surface energy and wettability increase. To evaluate the efficiency of this process, we studied connection of the ADBD supply energy/voltage frequency and changes of the polymer surface chemical composition. ADBD was operated in the filamentary regime. Experiments proved that growing supply voltage frequency that produced also reactor input energy increase allowed both substantial reduction of treatment time and more effective modification.Конечные свойства полимеров являются компромиссом между желаемыми поверхностными и глубинными характеристиками. Существенное изменение потребительских свойств полимеров может быть вызвано модификацией характеристик его приповерхностных структурных слоев (т.е. на глубине нескольких десятков нанометров поверхностного слоя). Такая модификация может быть реализована с помощью облучения «холодной» плазмой без дополнительных затрат и минимального влияния на окружающую среду. Модификация поверхностных характеристик полимера может происходить во время обработки, когда компоненты плазмы взаимодействуют с молекулами поверхности полимера, при этом на поверхности полимера образуются новые химические группы. Эти химические реакции могут зависеть от состава газа в плазменном реакторе. Например, применение кислородной плазмы приводит к увеличению прочности поверхности полимера и ее смачиваемости. Чтобы оценить эффективность данного процесса, изучалась зависимость изменения химического состава поверхности полимера от параметров атмосферного диэлектрического газового разряда (ADBD). Эксперименты подтвердили, что увеличение питающей частоты разряда, а также входной энергии реактора приводит к существенному сокращению времени облучения и более эффективной модификации.Кінцеві властивості полімерів є компромісом між бажаними поверхневими і глибинними характеристиками. Істотна зміна споживчих властивостей полімерів може бути викликана модифікацією характеристик його приповерхневих структурних шарів (тобто на глибині декількох десятків нанометрів поверхневого шару). Така модифікація може бути реалізована за допомогою опромінення «холодною» плазмою без додаткових витрат і мінімального впливу на навколишнє середовище. Модифікація поверхневих характеристик полімеру може відбуватися під час обробки, коли компоненти плазми взаємодіють з молекулами поверхні полімеру, при цьому на поверхні полімеру утворюються нові хімічні групи. Ці хімічні реакції можуть залежати від складу газу в плазмовому реакторі. Наприклад, застосування кисневої плазми призводить до збільшення міцності поверхні полімеру і її змочуваності. Щоб оцінити ефективність даного процесу, вивчалася залежність зміни хімічного складу поверхні полімеру від параметрів атмосферного діелектричного газового розряду (ADBD). Експерименти підтвердили, що збільшення живильної частоти розряду, а також вхідної енергії реактора призводить до істотного скорочення часу опромінення і більш ефективної модифікації

Magnetic spectra analysis of dielectrics

Method of magnetic spectroscopy is used to analyze and to interpret the experimental data obtained by magnetic measurement of the complex permeability spectra of Mg ferrite and NiZn ferritepolymers. Ferritepolymers were prepared from various concentration of NiZn ferrite particles as a soft magnetic fillers dispersed in PVC polymer matrix. Effect of the filler content on the permeability spectra of NiZn ferritepolymers was examined and compared with presented sintered ferrite samples. The variations of permeability and relaxation frequency due to ferrite filler concentration in composite are presented and discussed from point of view the magnetization processes in samples

Optimization of Magnetic and Structural Properties of Sr Ferrite Prepared by Low-Temperature Combustion

Fine strontium hexaferrite particles were prepared by the low temperature auto-combustion method. Aqueous solution of the corresponding metal salts and a combustible co-reactant compound -glycine were used as initial precursor. The resulting powders were calcined at various temperatures from 750 • C up to 1100 • C. The microstructure and magnetic properties were investigated by the Mössbauer spectroscopy, thermomagnetic analysis, scanning electron microscopy, and vibrating magnetometer

Common and Distinct Roles of Juvenile Hormone Signaling Genes in Metamorphosis of Holometabolous and Hemimetabolous Insects

Insect larvae metamorphose to winged and reproductive adults either directly (hemimetaboly) or through an intermediary pupal stage (holometaboly). In either case juvenile hormone (JH) prevents metamorphosis until a larva has attained an appropriate phase of development. In holometabolous insects, JH acts through its putative receptor Methoprene-tolerant (Met) to regulate Krüppel-homolog 1 (Kr-h1) and Broad-Complex (BR-C) genes. While Met and Kr-h1 prevent precocious metamorphosis in pre-final larval instars, BR-C specifies the pupal stage. How JH signaling operates in hemimetabolous insects is poorly understood. Here, we compare the function of Met, Kr-h1 and BR-C genes in the two types of insects. Using systemic RNAi in the hemimetabolous true bug, Pyrrhocoris apterus, we show that Met conveys the JH signal to prevent premature metamorphosis by maintaining high expression of Kr-h1. Knockdown of either Met or Kr-h1 (but not of BR-C) in penultimate-instar Pyrrhocoris larvae causes precocious development of adult color pattern, wings and genitalia. A natural fall of Kr-h1 expression in the last larval instar normally permits adult development, and treatment with an exogenous JH mimic methoprene at this time requires both Met and Kr-h1 to block the adult program and induce an extra larval instar. Met and Kr-h1 therefore serve as JH-dependent repressors of deleterious precocious metamorphic changes in both hemimetabolous and holometabolous juveniles, whereas BR-C has been recruited for a new role in specifying the holometabolous pupa. These results show that despite considerable evolutionary distance, insects with diverse developmental strategies employ a common-core JH signaling pathway to commit to adult morphogenesis

The annual recurrence risk model for tailored surveillance strategy in patients with cervical cancer

Purpose: Current guidelines for surveillance strategy in cervical cancer are rigid, recommending the same strategy for all survivors. The aim of this study was to develop a robust model allowing for individualised surveillance based on a patient's risk profile. Methods: Data of 4343 early-stage patients with cervical cancer treated between 2007 and 2016 were obtained from the international SCCAN (Surveillance in Cervical Cancer) consortium. The Cox proportional hazards model predicting disease-free survival (DFS) was developed and internally validated. The risk score, derived from regression coefficients of the model, stratified the cohort into significantly distinctive risk groups. On its basis, the annual recurrence risk model (ARRM) was calculated. Results: Five variables were included in the prognostic model: maximal pathologic tumour diameter; tumour histotype; grade; number of positive pelvic lymph nodes; and lymphovascular space invasion. Five risk groups significantly differing in prognosis were identified with a five-year DFS of 97.5%, 94.7%, 85.2% and 63.3% in increasing risk groups, whereas a two-year DFS in the highest risk group equalled 15.4%. Based on the ARRM, the annual recurrence risk in the lowest risk group was below 1% since the beginning of follow-up and declined below 1% at years three, four and >5 in the medium-risk groups. In the whole cohort, 26% of recurrences appeared at the first year of the follow-up, 48% by year two and 78% by year five. Conclusion: The ARRM represents a potent tool for tailoring the surveillance strategy in early-stage patients with cervical cancer based on the patient's risk status and respective annual recurrence risk. It can easily be used in routine clinical settings internationally

Zircon ages in granulite facies rocks: decoupling from geochemistry above 850 °C?

Granulite facies rocks frequently show a large spread in their zircon ages, the interpretation of which raises questions: Has the isotopic system been disturbed? By what process(es) and conditions did the alteration occur? Can the dates be regarded as real ages, reflecting several growth episodes? Furthermore, under some circumstances of (ultra-)high-temperature metamorphism, decoupling of zircon U–Pb dates from their trace element geochemistry has been reported. Understanding these processes is crucial to help interpret such dates in the context of the P–T history. Our study presents evidence for decoupling in zircon from the highest grade metapelites (> 850 °C) taken along a continuous high-temperature metamorphic field gradient in the Ivrea Zone (NW Italy). These rocks represent a well-characterised segment of Permian lower continental crust with a protracted high-temperature history. Cathodoluminescence images reveal that zircons in the mid-amphibolite facies preserve mainly detrital cores with narrow overgrowths. In the upper amphibolite and granulite facies, preserved detrital cores decrease and metamorphic zircon increases in quantity. Across all samples we document a sequence of four rim generations based on textures. U–Pb dates, Th/U ratios and Ti-in-zircon concentrations show an essentially continuous evolution with increasing metamorphic grade, except in the samples from the granulite facies, which display significant scatter in age and chemistry. We associate the observed decoupling of zircon systematics in high-grade non-metamict zircon with disturbance processes related to differences in behaviour of non-formula elements (i.e. Pb, Th, U, Ti) at high-temperature conditions, notably differences in compatibility within the crystal structure

Effects of Methoxyisoflavone, Ecdysterone, and Sulfo-Polysaccharide Supplementation on Training Adaptations in Resistance-Trained Males

PURPOSE: Methoxyisoflavone (M), 20-hydroxyecdysone (E), and sulfo-polysaccharide (CSP3) have been marketed to athletes as dietary supplements that can increase strength and muscle mass during resistancetraining. However, little is known about their potential ergogenic value. The purpose of this study was to determine whether these supplements affect training adaptations and/or markers of muscle anabolism/catabolism in resistance-trained athletes. METHODS: Forty-five resistance-trained males (20.5±3 yrs; 179±7 cm, 84±16 kg, 17.3±9 % body fat) were matched according to FFM and randomly assigned to ingest in a double blind manner supplements containing either a placebo (P); 800 mg/day of M; 200 mg of E; or, 1,000 mg/day of CSP3 for 8-weeks during training. At 0, 4, and 8-weeks, subjects donated fasting blood samples and completed comprehensive muscular strength, muscular endurance, anaerobic capacity, and body composition analysis. Data were analyzed by repeated measures ANOVA. RESULTS: No significant differences (p>0.05) were observed in training adaptations among groups in the variables FFM, percent body fat, bench press 1RM, leg press 1RM or sprint peak power. Anabolic/catabolic analysis revealed no significant differences among groups in active testosterone (AT), free testosterone (FT), cortisol, the AT to cortisol ratio, urea nitrogen, creatinine, the blood urea nitrogen to creatinine ratio. In addition, no significant differences were seen from pr

Middle Jurassic collision of an exotic microcontinental fragment: implications for magmatism across the southeast China continental margin

Thrusting, folding and metamorphism of late Paleozoic to middle Mesozoic sedimentary rocks, together with high precision U–Pb zircon ages from Middle to Late Jurassic volcanic and granitic rocks, reveals evidence for a major deformation event in northwestern Hong Kong between 164 and 161 Ma. This episode can be linked with collision of an exotic microcontinental fragment along the southeast China continental margin determined from contrasting detrital zircon provenance histories of late Paleozoic to middle Mesozoic sedimentary rocks either side of a NE-trending suture zone through central Hong Kong. The suture zone is also reflected by isotopic heterogeneities and geophysical anomalies in the crustal basement. Detrital zircon provenance of Early to Middle Jurassic rocks from the accreted terrane have little in common with the pre-Middle Jurassic rocks from southeast China. Instead, the zircon age spectra of the accreted terrane show close affinities to sources along the northern margin of east Gondwana. These data provide indisputable evidence for Mesozoic terrane accretion along the southeast China continental margin. In addition, collision of the exotic terrane, accompanied by subduction roll-back, is considered to have hastened foundering of the postulated flat-slab beneath southeast China leading to a widespread igneous flare-up event at 160 Ma