Diagnosis of the thermocouple in the proces of gasification of biomass

One of the methods of obtaining energy from renewable sources is the biomass gasification. For economic reasons, and taking into account the security aspects, it is important to ensure that the process is optimal. The gasification process can be optimized regarding the product energy, especially concentration of hydrocarbons and their derivatives or tar substrates, such optimization requires precise knowledge of temperatures in the gasification reactor. The temperatures inside the reactor determine the speed and quality of gasification process and are one of the most important parameters for control and monitoring systems of gasifier operation. Thermocouples are most widely used for temperature monitoring. That is the reason why it is important to acquire precise temperature readout regardless of aging processes. The significance of accurate temperature determining has been demonstrated with the use of a simplified mathematical model of a reactor assuming ideal reagents mixing. The presented mass and energy balance equations have led to determine the temperature changes during the analyzed process. The final equation is a base for the optimization of the gasification process and contains quantity of measured temperature. The main problem is the accuracy of temperature measurement. The authors have developed the in-situ method of diagnostics of thermocouples, that allows determination of the relative deviation of the sensor thermoelectric force during its operation. Besides characteristic parameters such as material properties the model includes the internal heat transfer, as well. The presented diagnostic method consists in determining the electromotive force of a newly installed sensor, and then determination of characteristic parameters using two selected values of testing current. During operation of the monitored sensor, periodic determination of the relative deviation of the Seebeck coefficient is required. This relative deviation should be compared to its permissible level, that is specified for the process being monitored. The proposed method belongs to the class of comparative ones, where the comparison is related to the indications of the same sensor (the new one and in-service). Experimental verification of the presented method was carried out using gasifier with nominal thermal load of 50kW, fed with wood pellets. The temperature of synthesis gas was measured by the two sensors, the reference sensor and the second one, that was driven by pulses of a testing current. For both current directions the thermoelectric force has been determined. The difference of the obtained electromotive forces is diagnostic information, that is needed to calculate the relative change of the Seebeck coefficient. The proposed solution allows diagnosing thermocouples located in confined areas. Moreover, additional benefit is the possibility of sensors diagnosis without stopping the process being monitored. It is important for both economic and technological reasons

Significant terms of the contract to provide advertising services

Розглянуто основні доктринальні вчення та нормативне врегулювання питань, пов’язаних з істотними умовами цивільного договору та окремо договору про надання рекламних послуг. Проведено аналіз проблемних аспектів, пов’язаних з існуючими на сьогодні істотними умовами договору. Встановлено негативний вплив існуючих прогалин діючого законодавства України на належне виконання вимог законодавства України про рекламу. Запропоновано шляхи вирішення існуючих проблемних аспектів встановлення істотних умов договору про надання рекламних послуг.Рассмотрены основные доктринальные учения и нормативное урегулирование вопросов, связанных с существенными условиями гражданского договора и отдельно договора о предоставлении рекламных услуг. Проведен анализ проблемных аспектов, связанных с существующими на сегодня существенными условиями договора. Установлено негативное влияние существующих пробелов действующего законодательства Украины на надлежащее исполнение требований законодательства о рекламе. Предложены пути решения существующих проблемных аспектов установления существенных условий договора о предоставлении рекламных услуг.The basic doctrinal teachings and regulatory compliance issues related to the essential terms of a civil contract and a separate contract for the provision of advertising services. The analysis of the problematic aspects associated with today's essential terms of the contract. Negative influence of the gaps in the current legislation of Ukraine proper implementation of the law on advertising. Proposed solutions to the existing wife problematic aspects of the establishment of the essential conditions of the contract to provide advertising services

Sunshine as culprit: It induces early spring physiological drought in dark coniferous (Pinus sibirica and Abies sibirica) alpine forest

Trees comprising high mountain forests have different requirements for site conditions (such as the water supply), thus current climate warming leads to varying reactions of upper forest boundaries depending on the site conditions and ecophysiological features of species. Positive reactions to an increasing heat supply during vegetative season may be hindered for drought-sensitive species by a water deficit in a cold environment, particularly during late winter or early spring. We investigated the radial growth of dark coniferous forest species Siberian stone pine (Pinus sibirica Du Tour) and Siberian fir (Abies sibirica Ledeb.) growing on slopes of different orientation (south-west, east, and north) near the upper forest boundary in an area undergoing fast climate warming: the Western Sayan Mountains (South Siberia, Russia), near a massive water reservoir. Correlations of tree-ring width chronologies with moving 21-day temperature series were used to more precisely determine the timing of temperature influence; an analysis of extreme and optimal years and multifactor regression modeling were applied to assess the most favorable/unfavorable thermal conditions in the study area and to estimate the tree growth reaction to the current climatic trends, respectively. Despite relatively low variation in growth (standard deviation <0.2), a significant common climatic signal in tree-ring width was found at all sampling sites. On the shaded northern slopes, P. sibirica is only mildly limited by summer temperatures and has a low similarity (correlations and synchronicity of extreme/optimal years) with other sites. Conversely, the growth of A. sibirica and P. sibirica on two sunlit slopes is similar (r = 0.44–0.81) and has a common pattern of regulation by temperatures before (r = −0.17…−80.40; April 3 – May 4 on average) and more significantly during vegetative season (r = 0.31…0.44; May 17 – August 27 on average). We hypothesize that both species, being drought-sensitive, undergo water stress in the early spring, and exposition of previous years’ needles to severe temperature variation may lead to partial defoliation and xylem embolism, thus suppressing growth. The patterns of climatic response and species distribution on slopes indicate that A. sibirica is more sensitive to this physiological drought and needs gentler slopes than P. sibirica. Temperature increase in the study area during the last decades have occured about five times faster in the early spring (being enhanced by the reservoir) than in summer. This combination of spring and summer warming leads to an increase in P. sibirica radial growth on the northern slope and the stable growth of both species on sunlit slopes, i.e. providing a tentatively optimistic assessment of the dark coniferous forests’ near future in the region

Optical Method for Biomass Syngas Monitoring

One of the methods of increasing the overall biomass share in the electricity and heat production is its gasification and subsequent co-combustion of the obtained syngas in conventional power boilers. The process of biomass gasification is relatively well controlled and understood. It does not change the fact that the syngas composition depends on many process factors, as well as the composition of the charge batch. Unfortunately, it means that the obtained product is not homogeneous in time. Consequently, the use of such fuel for electricity production may present a number of problems from the control point of view. Therefore, both during the syngas production and the co-firing process, it is advisable to use information on the composition of produced syngas, or at least its main components. It is possible to use optical methods, which are an interesting alternative to classical methods, even despite unfavorable measurement conditions. The article presents selected optical method for the synthesis gas monitoring. The results of simulation studies are presented, confirming the possibility of determining the concentration of interesting components in the syngas mixture

Primary Sjogren's syndrome in practice of gastroenterologist: difficult issues of diagnosis and treatment (clinical observation)

Sjogren's syndrome is a systemic connective tissue disease characterized by pronounced clinical polymorphism, which can be encountered in outpatient practice by doctors of various specialties. The article discusses the problems of the resistant course of gastroesophageal reflux disease, which developed against the background of the primary Sjogren syndrome, on the example of clinical observation. The role of in-depth examination of the patient for the correct clinical diagnosis and the involvement of a team of specialists to achieve remission of Sjogren's syndrome is emphasized.</jats:p

An integrated approach to environmental management

Abstract The issues of improving the system of environmental management on the basis of knowledge management, risk-based approach, environmental monitoring are covered in the article. As a result of the carried out researches the algorithm of improvement of system of ecological management is developed. The model of improvement of ecological monitoring is offered. Practical recommendations for improving environmental safety and placing points of observation of the state of the environment are presented.</jats:p

New quality of measuring capabilities

Abstract The issues of improving the quality of measurements based on the use of information technology and the informatization of the metrological infrastructure are investigated using the example of measurements of volumetric fluid flow. The functional diagram of an automated calibration unit for checking water flow meters is analyzed. As a result of the research, a model for the formation of a new quality of measuring capabilities has been developed. The use of metrological self-monitoring of calibration facilities is justified.</jats:p