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Tytuł:
Analysis of pubescent oak (Quercus pubescens Willd.) by means of chloroplast DNA (cpDNA) in the western part of the Balkan Peninsula
Autorzy:
Ballian, D.
Ivankovic, M.
Grycan, J.
Peric, S.
Marjanovic, H.
Bobinac, M.
Slade, D.
Powiązania:
https://bibliotekanauki.pl/articles/57477.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
pubescent oak zob.downy oak
downy oak
oak
Quercus pubescens
chloroplast
cpDNA
Balkan Peninsula
genetic variability
population diversity
plant population
Opis:
In the area of the western Balkans, xerothermal broad-leaf forests hold a very special position, the main species being pubescent oak (Quercus pubescens Willd.). The study comprises 36 populations of pubescent oak from Croatia, Bosnia and Herzegovina, Montenegro, Kosovo, Albania and Macedonia. Genetic variability and population diversity was analysed on chloroplast DNA in order to determine to which haplotype an individual or studied population belongs, as well as how they are related. For the detection of one haplotype analysed four sequences (AS, TF, DT and CD) on the chloroplasts DNA. The results of the analysis suggest that there are six different haplotypes of pubescent oak (2, 4, 5, 17, 31, 33) in the studied populations. Two more sub-haplotypes were found in haplotype 5 (a and b), but only in populations occurring in Croatia and Bosnia and Herzegovina. The results suggest the great variability of pubescent oak in the researched area, which is generally characteristic of other species from the area of the Balkan Peninsula. The results obtained by means of cpDNA analysis can help in the formation of seed zones. However, due to the strong selection pressure of unplanned logging, and the possible introduction of herbal material of unknown origin, it is necessary to find a sufficient number of autochthonous entities (i.e., populations of the researched species) as well as new suitable markers for their characterization. The results of this paper constitute a scientifically recognised, partial examination of the origin of the starting forest reproductive material from the broader geographic area, thus serving future projects on its regeneration.
Źródło:
Acta Societatis Botanicorum Poloniae; 2010, 79, 3
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Morphometric analyses of the leaf variation within Quercus L. Sect. Cerris Loudon in Turkey
Autorzy:
Uslu, E.
Bakis, Y.
Powiązania:
https://bibliotekanauki.pl/articles/41514.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
morphometric analysis
leaf
variation
Quercus cerris
Turkey oak
Austrian oak zob.Turkey oak
oak
cluster analysis
numerical taxonomy
principal component analysis
Turkey [geogr.]
Opis:
Oaks are classified heavily based on the leaf morphology. However, identification of specimens without acorns is usually controversial in Cerris section. Although members of Cerris section have a broad distribution area, there are only few taxonomic studies. Therefore, the current study is the first to show the discrimination of species in Cerris section based on leaf characters from Turkey. Discrimination among the members of Cerris section over Turkey (Q. cerris L. var. cerris, Q. ithaburensis Decne. subsp. macrolepis (Kotschy) Hedge and Yalt, Q. brantii Lindley, Q. libani Olivier, and Q. trojana P. B. subsp. trojana.) was aimed and variations within and among the species based on 15 qualitative leaf characters was presented. In this work we have studied the natural variability of these species by analysing leaf materials collected from 44 populations around Turkey. Cluster Analysis (CA) and Principal Component Analysis (PCA) were performed to assess intra-specific differentiation and to compare the distribution of variance in the individual and population level. The results showed that the leaf characters presented a good discrimination of five Cerris taxa in PCA at the population level, but the relationships between Q. ithaburensis subsp. macrolepis and Q. brantii showed complex groups in CA. Among the studied taxa, the highest variation was found within Q. cerris populations. In this work, we obtained discrimination of Cerris section species from Turkey based on leaf characters which is quite useful for those herbarium specimens without acorns and in other systematic observations.
Źródło:
Dendrobiology; 2014, 71
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tannin content in acorns (Quercus spp.) from Poland
Autorzy:
Luczaj, L.
Adamczak, A.
Duda, M.
Powiązania:
https://bibliotekanauki.pl/articles/41617.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
polyphenol
tannin content
acorn
oak acorn
oak
Quercus
phytochemistry
food security
Polska
Opis:
Oak acorns used to be an important human food, up until recent times. The major factor inhibiting their use in modern nutrition is their high tannin content. Polish oak trees were screened in order to find out whether there are any major geographical or interspecific differences in tannin and total phenolic contents in acorns, which might help us to establish further directions in the search for low-tannin individuals. We studied the level of phenolic compounds using the standard Polish and European Pharmacopoeia method, with Folin-Ciocalteu reagent and hide powder. Altogether 49 acorn samples of Quercus robur, 13 of Q. petraea, 1 of Q. pubescens (all native) and 12 of Q. rubra (introduced) were collected in different regions of Poland. The amount of investigated phenolics in Q. robur and Q. petraea acorns was similar, and tannins constituted the main component. The Q. pubescens sample was distinguished by the lowest tannin and total phenolic content and a relatively high amount of non-tannin phenolics. Q. rubra had a slightly lower tannin content than Q. robur and Q. petraea acorns, but the level of other phenolics was much higher. The results for Q. robur suggest geographical variability of phenolic content as well as a relationship between the phytochemical and biometric parameters of oak acorns.
Źródło:
Dendrobiology; 2014, 72
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature effects performance of Lymantria dispar larvae feeding on leaves of Quercus robur
Autorzy:
Karolewski, P
Grzebyta, J.
Oleksyn, J.
Giertych, M.J.
Powiązania:
https://bibliotekanauki.pl/articles/41435.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
herbivore insect
sex ratio
Lymantria dispar
larva
gypsy moth
feeding
leaf
oak
English oak
Quercus robur
pedunculate oak
temperature
performance
Opis:
Future climatic warming may modifyinsect development, sex ratio, quantitative changes in populations that could affect the frequency of outbreaks. Here we analyzed the influence of temperature on larval growth and development in the gypsy moth (Lymantria dispar L.). The larvae were reared at three constant temperatures: 15, 20 or 25°C, and fed with leaves of the English oak (Quercus robur L.). Larval mortality, duration of development (DD), relative growth rate (RGR), total mass of food eaten (TFE), and pupal mass (PM) were estimated. Larval mortality was lowest at 20°C, higher at 25°C, and highest at 15°C. DD significantly decreased with increasing temperature and depended on sex. The influence of temperature on the shortening of DD was stronger in males than in females. RGR significantly depended on temperature and was the highest at 25°C, and lowest at 15°C. At 15°C, RGR did not change markedly with time. In contrast, RGR at 20°C was characterized bya continuous decreasing trend. At 25°C, RGR was very high for 2 weeks but quickly declined afterwards. Temperature did not affect the TFE. PM was significantly correlated with temperature and sex. PM of females was higher at 20°C than at 15 and 25°C, in contrast to that of males, which was similar at 20 and 25°C, and higher than at 15°C. For larval growth and development, the most favourable was the medium temperature (20°C). The least favourable temperature for females was 25°C, for males 15°C. The results suggest that global warming may modifythe future sex ratio of gypsy moths that may affect insect development and outbreaks.
Źródło:
Dendrobiology; 2007, 58; 43-49
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the oak wood chips in brewing®
Zastosowanie płatków dębowych w browarnictwie®
Autorzy:
Bajerski, Mateusz
Klimczak, Krystian
Cioch-Skoneczny, Monika
Powiązania:
https://bibliotekanauki.pl/articles/2051417.pdf
Data publikacji:
2021
Wydawca:
Wyższa Szkoła Menedżerska w Warszawie
Tematy:
oak chips
oak
barrel
beer
aging
płatki dębowe
dąb
beczki
piwo
leżakowanie
Opis:
Oak chips are finely shredded oak fragments, which were toasted under strictly controlled conditions. They are produced in various grammages and degrees of toasting. Chips can be divided into natural, light, medium and heavily toasted. Their size affects how quickly ingredients are being released from them. The aim of the article is to present issues related to the application of oak chips in brewing, as an alternative to the oak barrels usage. The description presents information regarding the influence of the oak chips addition on the final profile of the drink and also characterizes the processes that take place during aging.
Płatki dębowe to drobno poszatkowane szczapy dębowe, które zostały upieczone w ściśle kontrolowanych warunkach. Produkowane są w różnej gramaturze i stopniu opieczenia. Wyróżnia się płatki naturalne, lekko, średnio i mocno opiekane. Rozmiar zrębków wpływa na szybkość wydobywania się z nich składników. Celem artykułu jest przybliżenie zagadnień związanych z zastosowaniem płatków dębowych w piwowarstwie, jako alternatywy dla wykorzystania beczek dębowych. W opisie przedstawiono informacje dotyczące wpływu dodatku zrębków dębowych na końcowy profil napoju, scharakteryzowano również procesy zachodzące podczas leżakowania piwa.
Źródło:
Postępy Techniki Przetwórstwa Spożywczego; 2021, 1; 124-129
0867-793X
2719-3691
Pojawia się w:
Postępy Techniki Przetwórstwa Spożywczego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of cutting off distal ends of Quercus robur acorns on seedling growth and their infection by the fungus Erysiphe alphitoides in different light conditions
Autorzy:
Giertych, M.J.
Suszka, J.
Powiązania:
https://bibliotekanauki.pl/articles/41420.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
oak
pedunculate oak
container nursery
oak powdery mildew
Quercus robur
seedling growth
plant infection
fungi
Erysiphe alphitoides
light condition
phenology
Opis:
Quercus robur seedlings are very often infested by oak powdery mildew caused by Erysiphe alphitoides. This disease attacks primary leaves with high insolation. In our experiment seedling growth in different light conditions was observed. Seedlings were derived from intact seeds or from seeds where the distal ends of acorns were cut off. Acorns were sown in pots at four light conditions (2%, 8% and 30% light transmittance and in full sunlight). For half of the seedlings we reduced the influence of powdery mildew by using a fungicide. Height of seedlings, shoot dry mass and the degree of damage caused by Erysiphe alphitoides were measured. The highest damages were in full light conditions and the lowest in the 30% light treatment. The influence of acorn reduction on powdery mildew infection was not significant (p=0.0763), however, in the full light conditions the seedlings from cut acorns were ca. 30% less damaged. The cutting of acorns also alters the height of seedlings and shoot mass. The tallest seedlings were from cut seeds growing in the 30% light treatment. The influence of the fungicide was lowest in the 30% light treatment where the decrease in damage was only ca. 10%. For nursery practice we can say that oak seedling production from cut off acorns under 30% light transmittance should give the best results of seedling growth even without the fungicide application.
Źródło:
Dendrobiology; 2010, 64
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Winter storage of pedunculate oak (Quercus robur L.) seedlings
Zimowe przechowywanie sadzonek dębu szypułkowego (Quercus robur L.)
Autorzy:
Wesoly, W.
Chabowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/791403.pdf
Data publikacji:
2016
Wydawca:
Wyższa Szkoła Zarządzania Środowiskiem w Tucholi
Tematy:
winter storage
storage
pedunculate oak
Quercus robur
seedling
oak
plant seedling
plant vigor
plant growth
Źródło:
Zarządzanie Ochroną Przyrody w Lasach; 2016, 10
2081-1438
2391-4106
Pojawia się w:
Zarządzanie Ochroną Przyrody w Lasach
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radial growth of pedunculate oak and European ash on active river terraces. Hydrologic and climatic controls
Autorzy:
Okoński, B.
Powiązania:
https://bibliotekanauki.pl/articles/100989.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Infrastruktura i Ekologia Terenów Wiejskich PAN
Tematy:
oak
ash
floodplain forest
radial growth
Opis:
The aim of this study was (1) to assess relationships binding hydroclimatic factors and radial growth of pedunculate oak and European ash growing on active terraces of river valleys; (2) to compare the growth reaction of these species from this location. Research site was located in a floodplain valley, within mid-course of the lowland section of the Warta River in the Lasy Czeszewskie Forest, Poland. The Warta River (length 808 km, basin area: 54,529 km2 ) is a mid-size European river, a tributary of the Odra River draining the North European Plain to the Baltic Sea. The sampled forest stand was an old growth composed of pedunculate oak and European ash mixed with other mature tree species. The main conclusions are: (1) ash in comparison to oak growing on the same site located on floodplains appeared to be both more sensitive to hydroclimatical features and less ecologically flexible as far as monthly pattern of water requirements is concerned, therefore adaptation to changing climatic conditions and drought may be a greater ecological challenge for ash than for oak in river valleys; (2) streamflow could be considered as the parameter that substituted precipitation well, or even was more important than precipitation, as far as availability of water for development of tree rings of ash and oak growing on active terraces of river valleys is concerned; however, the role of streamflow in radial growth developing decreased substantially during 20th century; (3) Standardized Precipitation Evapotranspiration Index (SPEI) as a measure of drought is a prospective parameter in dendroecological analysis, since it conveys real availability of water for trees.
Źródło:
Infrastruktura i Ekologia Terenów Wiejskich; 2017, III/1; 1075-1091
1732-5587
Pojawia się w:
Infrastruktura i Ekologia Terenów Wiejskich
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on wood submerged in the sea
Badania drewna zatopionego w morzu
Autorzy:
Pomian, I.
Fojutowski, A.
Wroblewska, H.
Komorowicz, M.
Kropacz, A.
Noskowiak, A.
Powiązania:
https://bibliotekanauki.pl/articles/52667.pdf
Data publikacji:
2010
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Drewna
Tematy:
MACHU project
bioindicator
cultural heritage
marine research
oak
sea
submerged wood
wood
submerged oak wood
testing
Opis:
The Polish Maritime Museum in Gdansk participated in the EU project MACHU aiming at creation of a system of location, making information on European subaqueous maritime cultural heritage available and dissemination of it. 7 EU countries co-operated in the project. The Wood Technology Institute contributed to research on durability of small oak wood samples submerged in the sea. The samples were considered bioindicator of changes. The outline of research in the project is presented below.
Centralne Muzeum Morskie w Gdańsku uczestniczyło w projekcie UE MACHU zmierzającym do stworzenia systemu lokalizacji, udostępnienia i upowszechnienia informacji o europejskim podwodnym morskim dziedzictwie kulturowym. W projekcie współpracowało 7 krajów UE. Instytut Technologii Drewna wziął udział w pracach w zakresie badań trwałości w warunkach zatopienia w morzu małych próbek drewna dębu traktowanych jako bioindykator zmian. Przedstawiono zarys badań w projekcie.
Źródło:
Drewno. Prace Naukowe. Doniesienia. Komunikaty; 2010, 53, 183
1644-3985
Pojawia się w:
Drewno. Prace Naukowe. Doniesienia. Komunikaty
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Abundance and diversity of fungi in oak wood
Autorzy:
Behnke-Borowczyk, J.
Kwasna, H.
Kokot, K.
Haluszczak, M.
Lakomy, P.
Powiązania:
https://bibliotekanauki.pl/articles/2077912.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
abundance
deadwood
diversity
fungi
ITS
Illumina
oak
Opis:
Deadwood is an important functional and structural component of forest ecosystems since it regulates nutrient cycling, serves as a carbon (C) pool, increases the C content in the soil, and is a source of resources, including water, for a wide range of saproxylic and non-saproxylic organisms. The abundance and diversity of wood-inhabiting fungi in six fallen, horizontally lying logs of Quercus petraea, in the 1st, 2nd and 3rd decay classes, in the Drawa National Park in Poland in 2015, were studied using the Illumina se- quencing technique. The total number of OTUs obtained (264 307) included sequences of culturable fungi (242 369 = 91.70%) and non-culturable fungi (7 056 = 2.66%). The dead oak wood was colonized by 277 taxa. Culturable fungi of Zygomycota, Ascomycota and Basidiomycota comprised 75% of taxa detected and were represented by 14, 139 and 53 taxa respectively. Non-culturable organisms were represented by 70 taxa. Fungi were classified into 18 groups: (i) typical soft rot fungi, (ii) phytopathogens potentially hazard- ous to trees, (iii) epiphytes and endophytes or weak, opportunistic pathogens, (iv) ectomycorrhizal species, (v) ericoid mycorrhizal species, (vi) crust fungi, (vii) resupinate basidiomycetes, (viii) saprotrophs and soil fungi, (ix) opportunistic human pathogens causing superficial or systemic mycoses, (x) pathogens of warm- or cold-blooded animals, (xi) ascomycetous yeasts, (xii) basidiomycetous yeasts, (xiii) antagonists of fungi, (xiv) producers of metabolites effective against pathogens, (xv) hyperparasites, (xvi) lichen-form- ing species, (xvii) partners of other fungi, (xviii) species rare or uncommon in nature. It was shown that: (i) coarse, woody debris of oak is host to abundant and diverse mycobiota, (ii) abundance and diversity of fungi increase with the decay continuum, (iii) oak logs can be a habitat of phytopathogens potentially haz- ardous to forest health, (iv) different phytopathogens favour wood in different decay classes, (v) abundance of pathogens decreases, and of ericoid mycorrhizal (or soil) species increases with the decay continuum. Maintaining different types of deadwood increases fungal diversity, but also the risk of diseases.
Źródło:
Dendrobiology; 2018, 80; 143-160
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fluctuations in mean stem volume of common oak (Quercus robur L.) depending on age of trees
Zmiany średniej miąższości pnia dębu (Quercus robur L.) w zależności od wieku drzewa
Autorzy:
Kazmierczak, K.
Pazdrowski, W.
Szymanski, M.
Nawrot, M.
Powiązania:
https://bibliotekanauki.pl/articles/9573.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Katedra Zastosowań Matematyki i Informatyki
Tematy:
fluctuation
stem volume
oak
common oak
Quercus robur
plant age
tree
growth curve
linear regression
multiple regression
Źródło:
Colloquium Biometricum; 2009, 39
1896-7701
Pojawia się w:
Colloquium Biometricum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling the potential distribution of the endemic oak Quercus vulcanica Boiss. & Heldr. ex Kotschy in Turkey from the last interglacial to the future: From near threatened to endangered
Autorzy:
Sarikaya, A.G.
Orucu, O.K.
Sen, I.
Sarikaya, O.
Powiązania:
https://bibliotekanauki.pl/articles/2130201.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
oak
biogeography
species distribution modelling
MaxEnt
biodiversity conservation
Opis:
The aims of this study are to model past (LIG, LGM and Mid-Holocene), present and future (2050 and 2070) distributions of the Quercus vulcanica Boiss. & Heldr. ex Kotschy by using Maximum Entropy, and to predict suitable areas for the conservation of the species for future planning. MaxEnt distribution modeling was used to model distributions. Results for past bioclimatic conditions show that the distribution area of the species expanded and then contracted (LIG to LGM and LGM to HOL). The modelling shows that the distribution range of the species will be narrower in the future. The species will be facing extinction towards 2070. Therefore, the conservation status of the species should be evaluated according to the present findings. Although the largest population of the Q. vulcanica is found in Isparta and Afyonkarahisar Provinces located in Southwestern Turkey, this area will not be suitable for the growth and survival of the species in the future. For this reason, a new nature reserve area should be established in a more suitable climate.
Źródło:
Dendrobiology; 2022, 88; 70-80
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of growth and increment in height of common oak (Quercus robur L.)
Analiza wzrostu i przyrostu wysokości dębu szypułkowego (Quercus robur L.)
Autorzy:
Kazmierczak, K.
Pazdrowski, W.
Manka, K.
Szymanski, M.
Nawrot, M.
Powiązania:
https://bibliotekanauki.pl/articles/9717.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Przyrodniczy w Lublinie. Katedra Zastosowań Matematyki i Informatyki
Tematy:
common oak
oak
Quercus robur
plant growth
growth curve
tree
increment curve
height
variation coefficient
correlation coefficient
linear regression
multiple regression
Źródło:
Colloquium Biometricum; 2008, 38
1896-7701
Pojawia się w:
Colloquium Biometricum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strength comparative analysis of furniture joints made of various materials
Autorzy:
Sydor, Maciej
Kwapich, Agnieszka
Pohl, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/2146686.pdf
Data publikacji:
2021
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
furniture fastener
particle board
MDF
plywood
pine
oak
HPL
Opis:
The strength comparative analysis of furniture joints made of various materials. The influence of the load on the angular deformation of the furniture joint samples made of various materials was studied. The tests were carried out for six types of furniture materials: chipboard, MDF, hardwood plywood, glued pine wood, glued oak wood and HPL and for three types of fasteners with different ways of fixing in connected elements: shape-thread, expansion-expansion and expansion-thread way of anchoring in material of boards. The joint samples were loaded with a bending moment only (without inducing transverse loadings). The maximum load capacity and load capacity at the 3° (0.052 rad) sample rotation was measured and then the stiffness coefficients were calculated. Considerable differences were found between HPL and others lignocellulosic materials. Expansion fasteners offer incredibly low joint rigidity. This was observed for all tested furniture materials, from soft (chipboard) to very hard (HPL). Expansion connectors work better in soft lignocellulosic materials than in hard materials. The main advantage of expansion fasteners, in comparison to shape-thread fasteners, is its low visibility in the joint and the technological ease of assembly. On the other hand, thread-shaped connectors offer much greater strength and stiffness of joints.
Analiza porównawcza wytrzymałości połączeń meblowych wykonanych z różnych materiałów. Zbadano wpływ obciążenia na odkształcenie kątowe próbek połączeń wykonanych z różnych materiałów stosowanych w meblarstwie: płyty wiórowej, MDF, sklejki liściastej, drewna sosnowego klejonego, drewna dębowego klejonego oraz HPL. W badaniach wykorzystano trzy rodzaje łączników: gwintowo-kształtowy (mimośrodowy), rozprężnorozprężny i gwintowo-rozprężny. Próbki połączeń zostały obciążone wyłącznie momentem zginającym (bez wywoływania sił ścinających). Zmierzono nośność maksymalną oraz nośność przy odkształceniu 3° (0,052 rad), a następnie obliczono współczynniki sztywności połączeń. Stwierdzono znaczne różnice w wytrzymałości między HPL a innymi materiałami lignocelulozowymi. Łączniki rozprężne zapewniają bardzo małą sztywność połączenia. Zaobserwowano to dla wszystkich badanych materiałów meblowych, od miękkich (płyta wiórowa) po bardzo twarde (HPL). Łączniki tego typu lepiej sprawdzają się w miękkich materiałach lignocelulozowych niż w materiałach twardych. Główną zaletą łączników rozporowych, w porównaniu do łączników gwintowo-kształtowych, jest ich mała widoczność w połączeniu oraz technologiczna łatwość montażu. Z drugiej strony łączniki gwintowokształtowe oferują znacznie większą wytrzymałość i sztywność połączeń.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology; 2021, 113; 89--98
1898-5912
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Galasy rodzimych gatunków dębu jako potencjalny surowiec garbnikowy
Gall-nuts of native oak species as a potential tannin raw material
Autorzy:
Bilek, M.
Kozlowska-Tylingo, K.
Gostkowski, M.
Staniszewski, P.
Powiązania:
https://bibliotekanauki.pl/articles/980195.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
uboczne uzytkowanie lasu
dab
Quercus
galasy
garbniki
taniny
zawartosc garbnikow
forest utilisation
non−wood forest products
oak
oak gall−nuts
tannins
Opis:
Oak gall−nuts are pathological excrescences on the leaves of oaks (in Poland: Quercus robur L. and Q. petraea Liebl.) created by the Cynips quercusfolii L. The potential medical use of these non−wood forest products should be taken under consideration because of widespread use in folk medicine, but also because of the presence of gall−nuts of Middle Eastern oak species Quercus infectoria in the current Farmakopea… [2017]. The aim of this study was the preliminary analyzes of Quercus robur L. galls in the context of the diversity of the raw material and its possible consequences for the variability in tannin content, and therefore for the therapeutic value. The galls were collected in September 2018 from five living trees forming compact mid−field tree plantation in Podkarpackie Region (SE Poland). To determine the tannin content, hide powder method was used, while mass spectrometry was used for determining the identity of the raw material. The tannin content was found to be between 10.02 ±0.2% and 15.47 ±0.07%. There were no statistical differences between the tannin content of four weight groups of tested gall−nuts. The analysis of mass spectra showed the presence of gallic acid and tannin disintegration products. The results indicate that the tannin content in domestic oak galls is lower than in Quercus infectoria ones, for which less than 20% is required, however Polish galls are still the richest native tannin raw material. It was not proved that the content of tannins in oak galls was influenced by their size. A large variation in tannin content depending on the sample suggests that it might be possible to identify i.e. forest sites or climatic zones, where the obtained gall−nuts will be characterized by the high tannin content.
Źródło:
Sylwan; 2019, 163, 09; 746-753
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 51

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