Comparative analysis of wood pellet parameters: Canadian case study

Canada is one of the world leaders in wood pellet production and export, however, domestic consumption is extremely low. In addition there is no national standard in Canada for wood pellets. The Canadian government announced that it will increase wood pellet usage as an alternative to coal and natural gas. Wood pellets when compared to natural gas and coal, is an environmental friendly, energy-intensive and easily transported alternative. An independent comparative analysis of prime class (residential) wood pellets was performed in this study. We tested eight producers from five Canadian provinces (BC, ON, MB, NS and QC). The measurements of pellet quality characteristics (i.e., calorific value, moisture content, ash content, durability, bulk density, fines amount, compressive strength, fixed carbon and volatile organic compounds) were analysed. We carried out a statistical analysis of our results with the intent of finding interdependences between parameters. The analysis results show that average values of tested parameters are matching European and North American standards. Significant correlations between several parameters were found. It was also noted that there is a significant correlation between compressive resistance and pellet durability. Therefore, it was found that it is possible to use the compressive resistance test for rapid determination of pellet quality. A linear regression model for predicting mechanical durability was also developed. According to the comparative analysis it will be possible to set parameters equal to other countries for future national standard development in Canada. This will give an opportunity to increase domestic consumption and bring biomass energy through micro-generating and heating projects to geographically isolated areas and to small forest communities as an alternative and easily accessible energy source

Lignocellulosic materials in hydrolysis and spent liquors

Biomass pretreatment is widely used for softening biomass prior to its disintegration for value added product production. There are numerous methods for biomass pre-treatment, among which alkaline pulping and acid hydrolysis are the most widely applied. Hydrothermal treatment or autohydrolysis has a similar concept of action to acid hydrolysis, while autohydrolysis is the chemical-free and environmentally friendly technology. Hydrothermal and alkaline pulping pretreatments lead to lignin and polysaccharide dissolutions in hydrolysate and spent liquor (SL), respectively. Lignin and carbohydrates presented in hydrolysates and SL can be used for manufacturing value-added products. Lignin can be employed in carbon fiber, phenol formaldehyde, and hydrogen productions, for example, and hemicelluloses could be used for ethanol or xylitol production. However, the direct conversion of lignocellulosic materials present in hydrolysates and SL to value-added products is expensive due to their low concentrations. Lignocelluloses can be isolated from these liquors via acidification, solvent precipitation and membrane filtration. It is well known that lignocelluloses have different properties. Pulping and pretreatment processes have also great impacts on the properties of the extracted lignocellulose in liquors. Despite their effectiveness in isolating lignocelluloses, the impact of lignocelluloses properties on the efficiency of extraction processes is unknown. In this dissertation, the effect of autohydrolysis parameters on the properties, structure and composition of extracted lignocellulosic material was investigated. Also, the effect of lignocellulose's properties presented in hydrolysates and SL on the efficiency of acidification and solvent extraction was examined. The efficiency of lignocelluloses extraction from softwood chips via flow through autohydrolysis pretreatment was investigated in this PhD study. The highest temperatures applied in the autohydrolysis process were found to yield maximum removal of lignin from wood; whereas, prolonged hydrothermal treatment increased the removal of hemicelluloses from wood. In addition, it was discovered that a low flow velocity led to higher lignocelluloses removal. However, at high liquid flow rates hemicelluloses with larger molecular weight (Mw) were extracted. Gel permeation chromatography (GPC) analysis revealed the presence of lignin-carbohydrate complexes (LCC) in the hydrolysates. The GPC analysis showed that the hydrolysate generated in autohydrolysis treatment with a high liquid to solid (L/S) ratio contained a significantly lower amount of lignin presented in the LCC form. Moreover, 2D HSQC NMR spectroscopy revealed the existence of LCC linkages only in lignocellulosic materials obtained via lyophilisation of hydrolysate produced at the lowest autohydrolysis severity. The material generated as the result of mixing ethanol with hydrolysates produced at low autohydrolysis intensity showed the highest sugar content and negligible lignin content. Acidification of hydrolysates generated at high severity conditions led to extraction of almost pure lignin. The isolated material produced from hydrolysates due to ethanol or acid addition showed approximately twice as much heat capacity values as that of dried hydrolysates. The 1H-NMR analysis revealed that the extracted materials via acidification contained more methoxyl groups and a lesser degree of cross-linking than those present in hydrolysate. The GPC analysis also suggested the presence of LCC in the hydrolysates before and after treatment processes. In addition, the current research studied the properties, structures, and composition of lignocelluloses in spent liquors before and after isolation. Furthermore, the effect of organic solvents (i.e., ethanol, acetone, isopropyl alcohol) on lignocelluloses removal and the properties of the isolated lignocelluloses were determined. In examining the impact of the solvent type, it was discovered that hemicelluloses isolation had the highest isolation at the lowest solvent concentrations. While acetone and isopropyl were found to be efficient for lignosulfonate extraction, the highest hemicelluloses removal was achieved with ethanol treatment. The molecular weight and charge density of isolated lignocelluloses was higher when ethanol was used in comparison with acetone and isopropyl. The examination of the heating values, ignition temperatures, and heat capacity values of the precipitates revealed the possibility of using these materials as fuel or additives in briquette production. Additionally, a direct correlation between the inorganic content of the extracted lignocelluloses and their Tg values was discovered. The results achieved in this dissertation can be used as guidelines for developing biorefining processes for generating lignocelluloses with different properties from hydrolysate or spent liquors of different pulping processes. In addition, information available in literature on the structure and properties of lignin-carbohydrate complexes (LCC) as well as their production, analysis and application were discussed and critically evaluated

High School Paper Textbooks Usability: Leading and Satisfaction

AbstractThe work shows the research results of dependence of generated dissociated texts spatial structure satisfaction degree from a text spatial characteristic. The randomized sample was composed of 50 student age people from Institute of Professional Education and Information Technologies of the Bashkir State Pedagogical University, Ufa city, Russian Federation. As the only independent variable which characterizes spatial organization of the text the leading was used - total 13 grades from 0.8 to 2.2. The text printed on white paper substrates was reviewed by respondents with constant light conditions. The dependence of the page spatial structure positive assessment frequency from the leading has a maximum in range of 1.35–1.85. The ranking method offered allow to reveal the internal structure of assessments. In the field of low leadings a consensus assessment was observed in the range of 0.8–1.6. In the field of high leadings assessments were polar, therefore a bimodality was observed

Real-time intensity domain characterization of fibre lasers using spatio-temporal dynamics

Fibre lasers are light sources that are synonymous with stability. They can give rise to highly coherent continuous-wave radiation, or a stable train of mode locked pulses with well-defined characteristics. However, they can also exhibit an exceedingly diverse range of nonlinear operational regimes spanning a multi-dimensional parameter space. The complex nature of the dynamics poses significant challenges in the theoretical and experimental studies of such systems. Here, we demonstrate how the real-time experimental methodology of spatio-temporal dynamics can be used to unambiguously identify and discern between such highly complex lasing regimes. This two-dimensional representation of laser intensity allows the identification and tracking of individual features embedded in the radiation as they make round-trip circulations inside the cavity. The salient features of this methodology are highlighted by its application to the case of Raman fibre lasers and a partially mode locked ring fibre laser operating in the normal dispersion regime

THE FORMATION OF PROFESSIONAL WORLD VIEW OF THE CADETS OF MILITARY SCHOOLS OF HUMANISTIC AND CULTURAL ASPECTS

 Цель. В статье рассматривается проблема формирования мировоззрения военного специалиста, которая приобрела особую актуальность в условиях современного военного образования. Проводится теоретико-методологический анализ научных подходов, в рамках которых рассматривается обозначенная проблема. Предметом анализа выступают теоретические подходы к указанной проблеме, мыслителей и ученых разных исторических эпох. Авторы ставят своей целью раскрыть категории профессиональное мировоззрение офицера, гуманистические и культурные ценности.Метод или методология проведения работы. Основу исследования составляют классические методы теоретического ретроспективного анализа и синтезаРезультаты. Проведённый теоретический анализ позволил прийти к выводу о том, что профессиональное мировоззрение будущего офицера Росгвардии имеет свою специфику и представляет собой сложное системное образование включающее множество компонентов. Автор делает предположение о том, что одно из стратегических направлений развития системы образования в вузах войск национальной гвардии Российской Федерации видится в расширении информационного и культурного полей взаимодействия.Область применения результатов. Результаты исследования могут быть внедрены в образовательный процесс высшего военного профессионального образования.Purpose. The article is devoted to the topical issue for the military organization of Russia – the elements that make up the professional worldview of a military specialist. The subject of the analysis are theoretical approaches to this problem, thinkers and scientists of different historical eras. The authors aim to reveal the categories of professional Outlook of the officer, humanistic and cultural values.Methodology or methodology of the work. The study is based on classical methods of theoretical retrospective analysis and synthesisResults. The results of the work are that the authors on the basis of theoretical analysis and existing approaches state that the professional Outlook of the future officer of Regardie has its own specifics and is a complex system education including many components. The author makes an assumption that one of the strategic directions of development of the education system the universities of the national guard of the Russian Federation and cultural fields of interaction.The scope of the results. The results of the study can be applied in the field of higher military vocational education

Improvement of the method for assessing the energy load of vehicle

The aim of the research is to improve the indicators assessment accuracy of the vehicle energy load by improving the method of experimentally - theoretical determination of the aerodynamic drag parameters of vehicle in motion. To achieve this goal, it is necessary to solve the problem of determining the dependence of the energy load level on vehicle speed with varying frontal aerodynamic drag coefficient. Studies carried out to clarify the calculation of the parameters of vehicle aerodynamic drag in motion made it possible to determine the correlation between the actual effective engine capacity and the maximum kinetic energy of vehicle at translational motion. When determining the vehicle aerodynamic drag, the constant coefficient of aerodynamic drag is used depending on the speed in all range of vehicle speeds. This leads to significant mistakes in determining the necessary engine capacity expendable to overcome the aerodynamic drag, and vehicle fuel consumption. As a result of the research, analytical expressions, allowing to take into account additional energy losses and correlation between the kinetic energy of the vehicle steady motion and the effective engine capacity have been obtained. The theoretical contribution of the research is that the correlation coefficient between the kinetic energy of vehicle in motion and the effective engine capacity – have been proposed. Studies have shown that if speed of vehicle increases the indicator will monotonously decrease in the range of actual speeds

Exact analytical solutions and corresponding Monte Carlo models for the problem of light transport in turbid media with continuous absorption and discrete scattering at the single scattering approximation

Although the radiative transport theory is widely used in various biomedical, ocean, and atmospheric optic problems, there are few light transport problems that can be solved analytically. Therefore, Monte Carlo (MC) numerical simulations are used in most practical applications. In this study, light transport problems in continuously absorbing and discretely scattering media for pencil-like incident beams were considered theoretically using the single scattering approximation. Strict and closed-form analytical solutions to these problems were derived and compared with МС numerical results. Two sets of probabilistic parameters for the MC algorithm were explored. The first was the classical set for media with continuous absorption and smooth scattering, while the second was the newly substantiated set for media with continuous absorption and discrete scattering corresponding to the analytical medium's model. It was shown that if the same model was used in MC simulations and the analytical approach, all of the results were identical. A divergence up to 10% between the obtained analytics and MC results in the case of continuous absorption and smooth scattering was observed.PostprintPeer reviewe

GIS-MODELING OF LAKE ONEGO SHORELINE IN THE HOLOCENE AND LATE PLEISTOCENE

The application of GIS software for reconstruction of Lake Onego shoreline in the Holocene and the Late Pleistocene presented. Reconstruction was originated from the ideas of the Lake Onego depression deglaciation model proposed by I. Demidov [1] and the data of E. Deviatova [2] concerning Lake Onego depression isostatic uplift in the Holocene. ArcGIS software was used to perform GIS-modelling which was based on the original digital elevation model of the lakebed and its watershed. Twelve digital paleogeographic maps were developed as a result. Paleogeographic maps were verified by hand-drawn images of I. Demidov and E. Deviatova and by matching the lake shoreline and the position of archeological sites. Maps are available on-line in the electronic form [3]. The surface area of the Lake was determined at different stages of its development. The quantitative data obtained in this study is valuable for estimation of the lake volumes and the rates of discharge in the past

Plastic strain arrangement in copper single crystals in sliding

Deformation of tribologically loaded contact zone is one of the wear mechanisms in spite of the fact that no mass loss may occur during this process. Generation of optimal crystallographic orientations of the grains in a polycrystalline materials (texturing) may cause hardening and reducing the deformation wear. To reveal the orientation dependence of an individual gain and simplify the task we use copper single crystals with the orientations of the compression axis along [11 1] and [110]. The plastic deformation was investigated by means of optical, scanning electron microscopy and EBSD techniques. It was established that at least four different zones were generated in the course of sliding test, such as non-deformed base metal, plastic deformation layer sliding, crystalline lattice reorientation layer and subsurface grain structure layer. The maximum plastic strain penetration depth was observed on [110]-single crystals. The minimum stability of [11 1]-crystals with respect to rotation deformation mode as well as activation of shear in the sliding contact plane provide for rotation deformation localization below the worn surface. The high-rate accumulation of misorientations and less strain penetration depth was observed on [11 1]-crystals as compared to those of [110]-oriented ones

Narrow-band generation in random distributed feedback fiber laser

Narrow-band emission of spectral width down to ∼0.05 nm linewidth is achieved in the random distributed feedback fiber laser employing narrow-band fiber Bragg grating or fiber Fabry-Perot interferometer filters. The observed line-width is ∼10 times less than line-width of other demonstrated up to date random distributed feedback fiber lasers. The random DFB laser with Fabry-Perot interferometer filter provides simultaneously multi-wavelength and narrow-band (within each line) generation with possibility of further wavelength tuning