Исследование изменения реологических свойств водоугольного топлива на основе низкосортных углей с применением механической обработки и химических добавок

Выпускная квалификационная работа 93 с., 35 рис., 13 табл., 35 источников литературы. Ключевые слова: уголь, водоугольное топливо, суспензия, гидроксид натрия, лигносульфонат, роторный аппарат модуляции потоков. Объектом исследования является водоугольная суспензия. Цель работы – исследование влияния механической обработки и химических добавок на реологические свойства водоугольной суспензии. В процессе исследования проводились измерения вязкости, плотности и седиментационной устойчивости водоугольной суспензии на основе разных марок углей, а также были изучены характеристики ее зажигания. В результате исследования была проведена оценка воздействия механической обработки и химических добавок на реологические характеристики водоугольного топлива.The graduation thesis includes 93 pages, 35 figures, 13 tables, 35 references. Keywords: coal, coal-water fuel, slurry, sodium hydroxide, lignosulfonate, rotary flow modulation device. The object of this research is coal-water slurry. Aim of work is to investigate nfluence of mechanical processing and chemical additives on rheological properties of coal-water slurry. Viscosity, density and sedimentation stability of coal-water slurry based on different brands of coal were studied during this research, as well as its ignition characteristics. The impact of mechanical processing and chemical additives on rheological characteristics of coal-water fuel was evaluated

The Influence of Leadership and Psychological Empowerment on Performance : An Empirical Study on the Indonesian Seafarers

The purpose of this study is to find out the influence of leadership and psychological empowerment of the Indonesian seafarers on their performance. This study uses a quantitative approach. The respondents in this study were 251 seafarers with a minimum one year’s working experience. The technique used to collect data was purposive random sampling. The instruments used for collecting data were adopted from the following instruments : Leadership MLQ-5X Rater (Avolio & Bass), the Psychological Empowerment Instrument (Spreitzer) and the Performance (Williams & Anderson and Van Scotter & Motowidlo). Data was statistically analyzed by using regression and path analysis. The results showed that both leadership and psychological empowerment has a positive influence on the performances. Keywords: Leadership; psychological empowerment; seafarer performance DOI: 10.7176/RHSS/9-12-05 Publication date:June 30th 201

The Relationship Between core self-evaluation (CSE) and Psychological empowerment for seafarers

The Purpose of the study is to find out the relationship between core self-evaluation (CSE)and psychologycal empowerment for seafarers. This study uses a quantitative approach. Sample use in study were 251 seafarers and officers who have minimum work experience of 1 year. The technique of data collection using two scales. Calculation of data analysis is conducted by using correlation with SPSS. The results showed that the self-evaluation and psychological empowerment are positively related. Originality/value of study introduces a fundamental personality trait, CSE, to the area of the ship's environment and shows its effect on empowerment psychological for seafarer

Influence of large-scale asperities on the stability of concrete dams

For concrete dams founded on rock, there are only a few options in the common analysis methods to account for large‐scale asperities. However, previous research alludes that they have a significant impact on the behaviour of interfaces under shear. This study investigates the behaviour of concrete dam scale models with varying interface geometries, under a realistic set of eccentric loads. The outcome of the scale model tests shows that not only the capacity of the scale models was significantly impacted by the asperities, but also the type of failure in the scale models.Influence of large-scale asperities on the stability of concrete damspublishedVersio

Kinerja Pelaut ditinjau dari jabatan yang dimiliki

The performance of seafarers is the concern of many parties when there are many cases of ship accidents occurring in the oceans. On board consists various positions that each have different tasks. The purpose of this study is to describe the performance of seafarers if associated with the position they bear (manager level and supervisor level). This study was conducted on 251 seafarers who had the last education of ANT III or ATT III and had worked for at least 1 year. The sampling technique is accidental sampling. The results showed that seafarers with dominant managerial level had moderate performance, as did seafarers with supervisory level. This means that they were able to perform their duties well, which includes performance tasks and contextual performance

A Cellular Automaton Framework for Infectious Disease Spread Simulation

In this paper, a cellular automaton framework for processing the spatiotemporal spread of infectious diseases is presented. The developed environment simulates and visualizes how infectious diseases might spread, and hence provides a powerful instrument for health care organizations to generate disease prevention and contingency plans. In this study, the outbreak of an avian flu like virus was modeled in the state of Tyrol, and various scenarios such as quarantine, effect of different medications on viral spread and changes of social behavior were simulated

Ichthyotoxicity of the Dinoflagellate Karlodinium veneficum in Response to Changes in Seawater pH

The ichthyotoxic dinoflagellate Karlodinium veneficum has a worldwide distribution and produces highly potent lytic toxins (karlotoxins) that have been associated with massive fish kill events in coastal environments. The capacity of K. veneficum to gain energy from photosynthesis as well as phagotrophy enables cellular maintenance, growth and dispersal under a broad range of environmental conditions. Coastal ecosystems are highly dynamic in light of the prevailing physicochemical conditions, such as seawater carbonate speciation (CO2, HCO3−, and CO32−) and pH. Here, we monitored the growth rate and ichthyotoxicity of K. veneficum in response to a seawater pH gradient. K. veneficum exhibited a significant linear reduction in growth rate with elevated seawater acidity [pH(totalscale) from 8.05 to 7.50]. Ichthyotoxicity was assessed by exposing fish gill cells to K. veneficum extracts and subsequent quantification of gill cell viability via resorufin fluorescence. Extracts of K. veneficum indicated increased toxicity when derived from elevated pH treatments. The variation in growth rate and toxin production per cell in regard to seawater pH implies that (1) future alteration of seawater carbonate speciation, due to anthropogenic ocean acidification, may negatively influence physiological performance and ecosystem interactions of K. veneficum and (2) elevated seawater pH values (>8.0) represent favorable conditions for K. veneficum growth and toxicity. This suggests that prey of K. veneficum may be exposed to increased karlotoxin concentrations at conditions when nutrients are scarce and seawater pH has been elevated due to high photosynthetic activity from prior autotrophic phytoplankton blooms

From bit to it: How a complex metabolic network transforms information into living matter

Organisms live and die by the amount of information they acquire about their environment. The systems analysis of complex metabolic networks allows us to ask how such information translates into fitness. A metabolic network transforms nutrients into biomass. The better it uses information on available nutrient availability, the faster it will allow a cell to divide. I here use metabolic flux balance analysis to show that the accuracy I (in bits) with which a yeast cell can sense a limiting nutrient's availability relates logarithmically to fitness as indicated by biomass yield and cell division rate. For microbes like yeast, natural selection can resolve fitness differences of genetic variants smaller than 10-6, meaning that cells would need to estimate nutrient concentrations to very high accuracy (greater than 22 bits) to ensure optimal growth. I argue that such accuracies are not achievable in practice. Natural selection may thus face fundamental limitations in maximizing the information processing capacity of cells. The analysis of metabolic networks opens a door to understanding cellular biology from a quantitative, information-theoretic perspective

Application of tethered ruthenium catalysts to asymmetric hydrogenation of ketones, and the selective Hydrogenation of aldehydes

An improved method for the synthesis of tethered ruthenium(II) complexes of monosulfonylated diamines is described, together with their application to the hydrogenation of ketones and aldehydes. The complexes were applied directly, in their chloride form, to asymmetric ketone hydrogenation, to give products in excess of 99% ee in the best cases, using 30 bar of hydrogen at 60 °C, and to the selective reduction of aldehydes over other functional groups