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Search results for: THE ORIGIN OF WOOD
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The change of mechanical properties of selected wood species after drying process under various conditions
PublicationThe result of mechanical properties change of selected wood species after drying process under various parameters are presented. The global elasticity modulus and bending strength for steam dried, air-steam mixture dried and air dried samples as reference were measured. It allowed to reveal the effect of wood stream, air-steam mixture and their temperature on mechanical properties of wood. It has been recognized that steam and...
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CUTTING POWER FORECASTING WHILE WOOD SAWING: FRACTURE MECHANICS APPROACH AND AXELSSON’S MODEL COMPARISON
PublicationIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (power) could be considered from a point of view of modern fracture mechanics. Another way is to forecast cutting power consumption on...
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Geometrical conditions of saw blade`s entering into and going out of material during wood cutting
PublicationW pracy przedstawiono analizę geometrycznych warunków wejścia i wyjścia ostrza piły z materiału obrabianego przy przecinaniu drewna. Przedstawiono czasowy i przestrzenny rozkład geometrycznych parametrów wejścia i wyjścia ostrza i ich wpływ na trwałość ostrzy i dokładność przecinania.
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Forecasting values of cutting power for the sawing process of impregnated pine wood on band sawing machine
PublicationW artykule przedstawiono prognozowane wartości mocy skrawania dla pilarki taśmowej (ST100R firmy STENNER), które są stosowane w polskich tartakach. Wartości mocy skrawania oszacowano dla drewna sosny zwyczajnej (Pinus sylvestris L.), które zostało poddane impregnacji. Dla porównania wyznaczono również wartości mocy skrawania dla drewna niezaimpregnowanego. Wartości te określono za pomocą innowacyjnej metody prognozowania sił skrawania,...
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The impact of drying and steaming processes on surface color changes of tension ad normal beech wood
PublicationThe aim of the article is to present the influence of high temperature to selected properties of beech wood (Fagus sylvatica L.). The properties such as moisture content, color changes and longitudinal warping were analyzed. The quality of beech wood is determined based on structure and properties of wood, frequency of defects in wood material. The tension wood is considered as an important wood defect causing negative alterations...
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A newly-developed model for predicting cutting power during wood sawing with circular saw blades
PublicationIn the classical approach, cutting forces and cutting power in sawing processes of orthotropic materials such as wood are generally calculated on the basis of the specific cutting resistance kc (cutting force per unit area of cut). For every type of sawing kinematics (frame saws, band saws and circular sawing machines) different empirical values of specific cutting resistance kc have to be applied. It should be emphasised that...
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Determination of Moisture Content Profiles of Spruce Wood After High Temperature Process and Air Drying
PublicationThe results of moisture content of wood after the process of its drying under high temperature conditions and air drying are presented. Wood samples, namely spruce (Picea abies Karst.) from the northern part of Pomerania region in Poland, were subject of steam and air drying.The aim of experiments was to measure moisture content of wood in its cross sections using moisture meter WRD-100. The samples of thickness 70 mm and length...
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The dying medium temperature impact on the final moisture content of pine wood at constant drying time
PublicationThe results of final moisture content of pine wood (Pinus sylvestris L.) after drying process are presented. The wood in the experiments was taken from the northern part of Pomeranian region in Poland. The drying process was performed in the experimental chamber equipped with the micro-jet heat exchanger. The air at temperatures of 40°C, 60°C, 80°C, 100°C and 120°C with relative humidity about 60% and atmospheric pressure was the...
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The influence of high temperature wood drying conditions using air-steam mixture on its properties
PublicationThe results of properties change of beech wood after drying process are presented. The wood taken to experiments was from northern part of Pomeranian region in Poland. Before the main high temperature drying process using air-steam mixture, wood was initially dried in an open air conditions. The high temperature drying process was conducted at temperature 120oC, humidity 48%, flow rate of drying medium 2.5m/s and atmospheric pressure....
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Deformation and Surface Color Changes of Beech and Oak Wood Lamellas Resulting from the Drying Process
PublicationThe drying process was examined relative to parameters’ influence on the deformation and surface layer color changes of beech wood (Fagus sylvatica L.) and oak wood (Quercus robur L.). The goal was to analyze the impact of drying process conditions, wood and growth rings types, and load on the deformation and surface color changes of drying thin wooden elements. A further aim was to reduce the time of the lamella drying and minimize...
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Comparison of the fracture toughness of pine wood determined on the basis of orthogonal linear cutting and frame sawing
PublicationIn this paper, the values of the fracture toughness of Scots pine determined by cutting tests are presented. The cutting tests were carried out using the samples of Scotch pine (Pinus sylvestris L.) from Pomeranian Region, Poland. These experiments were carried out on two research stands: orthogonal linear cutting tests were conducted using the microtome instrument and the frame saw PRW-15M was used for sawing tests. The values...
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Theoretical and Actual Feed Per Tooth During Wood Sawing on an Optimizing Cross-Cut Saw
PublicationThe work presents the geometries of circular saw teeth, whose task is to divide the cross-cut of the cutting layer. For efficient machining on a cross-cut saw with high feed speed values (about 1 ms−1) maximal theoretical feeds per tooth are determined. These values were compared with the actual values determined during transverse cutting of pine wood on a special test stands in industrial conditions. In the experiment the rotational...
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Application of gas chromatography-mass spectrometry preceded by solvent extraction to determine volatile fatty acids in wastewater of municipal, animal farm and ladfill origin
PublicationW ramach przeprowadzonych badań została opracowana metodyka oznaczania lotnych kwasów tłuszczowych (LKT) z próbek ścieków pochodzących z oczyszczalni ścieków komunalnych, farm zwierząt oraz ze składowiska odpadów organicznych, techniką ekstrakcji ciecz-ciecz (LLE) za pomocą eteru metylo-tert-butylowego (MTBE) jako ekstahenta. Dobrano optymalne warunki chromatograficznego rozdzielania i oznaczania LKT w próbkach środowiskowych,...
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Studies on origin of Polish honeys by two-dimensional gas chromatography Ocena pochodzenia surowcowego polskich miodów przy użyciu dwuwymiarowej chromatografii gazowej
PublicationPolish acacia, linden, rapessed and buckwheat-derived honeys and a honydew were analysed for presence of hydrocarbons, alcs., ketones and esters by 2-dimensional gas chromatog. to establish the markers for the honey origin. PrOH was found characteristic for acacia honey, Me(CH2)11OH for linden honey, Me(CH2)6CHOMe for honeydew and Me(CH2)8COOEt for the rapeseed honey. Wykorzystano technikę dwuwymiarowej chromatografii gazowej sprzężonej...
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FOOD AND CHEMICAL TOXICOLOGY
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Comparative analysis of zinc status, food products' frequency intake and food habits of 11-year-old healthy children
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Maciej Wierzbowski dr inż.
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JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY
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Chemical, biological and functional aspects of food lipids
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The role of lipids in food quality. [Chapter] 9
PublicationZawartość lipidów zależy od gatunku i stanu dojrzałości surowców żywnościowych, a ich stabilność od interakcji z innymi składnikami oraz od warunków obróbki i składowania. Przemiany lipidów wpływają na barwę wielu surowców i produktów żywnościowych, szczególnie mięsa, ryb i bezkręgowców morskich a także na ich zapach. Lipidy uczestniczą w tworzeniu reologicznych właściwości produktów mięsnych i rybnych, emulsji, wyrobów piekarskich...
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Knowledge and knowledge management in agro-food systems
PublicationW artykule przedstawiono zagadnienia związane z zarządzaniem wiedzą w systemach rolno-spożywczych, a także możliwości zastosowania tej koncepcji w rozwoju zrównoważonym.
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Instrumental techniques used for assessment of food quality
PublicationW artykule scharakteryzowano dwie techniki instrumentalne stosowane w ocenie jakości produktów spożywczych, tj. chromatografię gazową w połączeniu z detekcją olfaktometryczną oraz nos elektroniczny. Opisano zasady działania obu technik oraz typowe procedury analityczne stosowane w ocenie zapachu. Ponadto, podano przykłady praktycznego zastosowania obu technik, włącznie z tymi, które wykorzystano w pracowni autorów.
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„Na początku było Słowo...” [„In the beginning was the Word...”]
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How Good are the Design Tools in Power Electronics?
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Chlorophylls and their Derivatives Used in Food Industry and Medicine
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Phycobilins and Phycobiliproteins Used in Food Industry and Medicine
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Aromagrams - aromatic profiles in the appreciation of food quality
PublicationW ostatnich latach obserwuje się coraz powszechniejsze stosowanie analizy instrumentalnej do oceny jakości organoleptycznej produktów spożywczych. Nowe podejście polega na tworzeniu profili zapachowych, swego rodzaju "aromagramów" charakterystycznych dla danego produktu. Do najczęściej stosowanych technik pozwalających na tworzenie i rozpoznawanie "aromagramów" należą techniki chromatograficzne, w szczególności chromatografia gazowa...
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[Chapter] 2. Thermostable enzymes in food processing
PublicationW rozdziale przedstawiono charakterystykę termostabilnych hydrolaz glikozydów, izomeraz, transferaz,lipaz i enzymów proteolitycznych w przetwórstwie rozmaitych surowców źywnościowych. Podano przyczyny termostabilności tych enzymów oraz wymieniono korzyści wynikające z ich stosowania.
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Knowledge and knowledge management in agro-food systems
PublicationArtykuł prezentuje zmiany, które się dokonały w systemach rolno-spożywczych, postrzeganych jako złożone sieci wzajemnie na siebie oddziałujących graczy. W artykule opisano również wyzwania, jakim te systemy muszą sprostać. Ponadto, zaprezentowano koncepcję zarządzania wiedzą i jej zastosowanie w systemach rolno-spożywczych.
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3-MCPD: A worldwide problem of food chemistry
Publication3-MCPD is a heat-induced food contaminant which has been widely investigated for decades. This paper presents an overview of current knowledge about 3-MCPD including its formation routes, occurrence in various foodstuffs, analytical approach, toxicological aspects and future research perspectives. So far 3-MCPD was determined in its free and bound form in thermally-treated foods, edible oils and fats, and infant foods including...
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Phytotherapy and food applications from Brassica genus
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Climate Changes in Southeastern Poland and Food Security
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Bringing Common Sense to WordNet with a Word Game
PublicationWe present a tool for common sense knowledge acquisition in form of a twenty questions game. The described approach uses WordNet dictionary, which rich taxonomy allows to keep cognitive economy and accelerate knowledge propagation, although sometimes inferences made on hierarchical relations result in noise. We extend the dictionary with common sense assertions acquired during the games played with humans. The facts added to the...
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Investigating Feature Spaces for Isolated Word Recognition
PublicationMuch attention is given by researchers to the speech processing task in automatic speech recognition (ASR) over the past decades. The study addresses the issue related to the investigation of the appropriateness of a two-dimensional representation of speech feature spaces for speech recognition tasks based on deep learning techniques. The approach combines Convolutional Neural Networks (CNNs) and timefrequency signal representation...
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Assessing Word Difficulty for Quiz-Like Game
PublicationMappings verification is a laborious task. Our research aims at providing a framework for manual verification of mappings using crowdsourcing approach. For this purpose we plan on implementing a quiz like game. For this purpose the mappings have to be evaluated in terms of difficulty to better present texts in respect of game levels. In this paper we present an algorithm for assessing word difficulty. Three approaches...
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Rough Sets Applied to Mood of Music Recognition
PublicationWith the growth of accessible digital music libraries over the past decade, there is a need for research into automated systems for searching, organizing and recommending music. Mood of music is considered as one of the most intuitive criteria for listeners, thus this work is focused on the emotional content of music and its automatic recognition. The research study presented in this work contains an attempt to music emotion recognition...
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Investigating Feature Spaces for Isolated Word Recognition
PublicationThe study addresses the issues related to the appropriateness of a two-dimensional representation of speech signal for speech recognition tasks based on deep learning techniques. The approach combines Convolutional Neural Networks (CNNs) and time-frequency signal representation converted to the investigated feature spaces. In particular, waveforms and fractal dimension features of the signal were chosen for the time domain, and...
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Nilpotent singularities and chaos: Tritrophic food chains
PublicationLocal bifurcation theory is used to prove the existence of chaotic dynamics in two well-known models of tritrophic food chains. To the best of our knowledge, the simplest technique to guarantee the emergence of strange attractors in a given family of vector fields consists of finding a 3-dimensional nilpotent singularity of codimension 3 and verifying some generic algebraic conditions. We provide the essential background regarding...
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Smartphones as tools for equitable food quality assessment
PublicationBackground: The ubiquity of smartphones equipped with an array of sophisticated sensors, ample processing power, network connectivity and a convenient interface makes them a promising tool for non-invasive, portable food quality assessment. Combined with the recent developments in the areas of IoT, deep learning algorithms and cloud computing, they present an opportunity for advancing wide-spread, equitable and sustainable food...
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20. Międzynarodowe seminarium mechanicznej obróbki drewna w Szwecji (20th international wood machining seminar)
PublicationW czerwcu 2011 roku w Szwecji odbyło się kolejne seminarium z zakresu obróbki drewna, na którym prezentowane były osiągnięcia w dziedzinie narzędzi skrawających do obróbki drewna, procesów obróbkowych i urządzeń. Liczne referaty, przedstawiane przez specjalistów wiodących ośrodków naukowych i przemysłu na sesjach plenarnych i plakatowych obejmowały prace typowo teoretyczne, eksperymentalne oraz opracowania o charakterze utylitarnym.
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Distribution of red wood ants (Hymenoptera: Formicidae) in the clear-cut areas of a managed forest in Western Poland
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The Effect of Wood Provenance and Density on Cutting Forces While Sawing Scots Pine (Pinus sylvestris L.)
PublicationSeveral properties of wood including the cutting power requirements can be correlated to wood density. Therefore, according to the literature, the cutting power requirements (and/or cutting forces) could be computed as a function of the wood specific gravity. This research shows that such an approach, based solely on specific gravity, may be considered a rather rough and imperfect estimate of cutting power. Samples of Scots pine...
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Revisiting The Determination Of Cutting Power While Sawing Of Wood With Circular Saw Blades By Means Of Fracture Mechanics
PublicationIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (power) could be considered from a point of view of modern fracture mechanics. Cutting forces may be employed to determine not only toughness...
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Non-Linear Analysis of Inter-Story Pounding between Wood-Framed Buildings during Ground Motion
PublicationPounding between adjacent buildings during ground motion may result in structural damage or lead to total destruction of structures. The research on the phenomenon has recently been much advanced; however, the analyses have been carried out only for concrete, steel, and masonry structures, while pounding between wooden buildings has not been studied so far. The aim of this paper is to show the results of detailed non-linear seismic...
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The association between irisin and muscle metabolism in different thyroid disorders
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The special clothing for firefighters – the normative requirements and original research results
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AN ORIGINAL APPROACH IN THE FIELD OF PREPARATION REFERENCE MATERIALS OF VOLATILE ANALYTES
PublicationStandard gas mixtures (SGM) are indispensable reference materials for ensuring the reliability of analytical work. Reference materials are an excellent tool for the quality control and assurance of analytical results. Standard gas mixtures are unique among reference materials. The rapid progress of SGM production is connected with the instability of gaseous analytes which make them difficult to obtain. The use of standards with...
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Enhancing seismic performance of rigid and semi-rigid connections equipped with SMA bolts incorporating nonlinear soil-structure interaction
PublicationNowadays, using smart connections can improve the performance of buildings with some recentering features that are from the superelastic behavior of Shape Memory Alloys (SMAs). It seems that there is different rigidity between the designed connection and the real one in Steel Moment-Resisting Frames (SMRFs), which can be considered as a problematic issue due to the importance of connections in seismic performance assessment. This...
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Bacterial Pathogens in the Food Industry: Antibiotic Resistance and Virulence Factors of Salmonella enterica Strains Isolated from Food Chain Links
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rigid polyurethane foams modified with selected nanofillers
PublicationThe nanofillers: natural montmoryllonite (MMT) - Bentonite, natural MMT modified with a quaternary ammonium salt - Cloisite30B, has been used in rigid polyurethane foams (PUFs). The influence of fillers amounts on processing parameters, physical-mechanical properties (density, water absorption, brittleness and compression strength) and thermal properties (thermal stability, fire behaviours) of such foams has been analysed. The...