Wyniki wyszukiwania - AGRO

1

Lozyska slizgowe z drewna

100%

W O.

Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie

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2004

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tom 44

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nr 1-2

80-81

2

Einfluss der Kaffeebraune von Tannenkernholz auf die Qualitat des Holzrohstoffs

100%

Paschalis P., Lotocka Z.

Annals of Warsaw Agricultural University. Forestry and Wood Technology

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1992

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tom 43

3

Disorders of programmed cell death in differentiating tracheids and anatomical abnormalities of Pinus sylvestris wood in polluted environment

100%

Rusin A., Tulik M.

Polish Journal of Natural Sciences. Supplement

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2003

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tom 01

4

Analyse von Schallsignalen bei der Holztrocknung

100%

Bernatowicz G., Niemz P.

Annals of Warsaw Agricultural University. Forestry and Wood Technology

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1992

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tom 43

5

Untersuchungen uber den Einfluss der Kaffeebraune von Eichenholz auf die Qualitat des Holzrohstoffes

100%

Paschalis P., Lotocka Z.

Annals of Warsaw Agricultural University. Forestry and Wood Technology

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1992

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tom 43

6

The impact of burning wood on air pollution

88%

Lis W., Tabert M., Mikolajczak E.

Intercathedra

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2014

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tom 30

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nr 2

The increasing energy consumption not only limits its accessibility but also contributes to the exhaustion of known and examined sources of that energy and the growth of its cost but mostly causes the increased emission of so-called greenhouse gasses – CO2, SOx, NOx, methane and so on. Those gases are responsible for significant climatic changes on our globe. Burning wood even though to a smaller extend than burning coal also contributes to that fact. Coal and wood as the result of burning simultaneously generate toxic substances – cancerogenic benzo(a)pyrene, heavy metals as well as dioxins and furans.

7

Age structure of compact sawing machines used for logging

88%

Kusiak W., Gorycki D.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2006

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tom 05

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nr 2

8

The effect of the Janka ball indentation depth on the hardness number determined for selected wood species

88%

Helinska-Raczkowska L., Molinski W.

Folia Forestalia Polonica. Series B - Drzewnictwo

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2003

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nr 34

9

A model describing forwarder based logging performance in pine stands thinnings

75%

Walczak M., Grodecki J.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2012

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tom 11

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nr 3

Logging is an important element of wood production. Its modelling gives an opportunity to compare different scenarios before the work has started and may be helpful in future operations planning. A computer program was created which includes basic factors influencing forwarder efficiency: parameters of the machine, the stand and the assortments. The results of the simulation confirm relations between certain factors and forwarder performance given by other authors. Counted absolute values may be higher than real. Relative comparison of relations between factors is more accurate.

10

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Natural drying of fruit trees wood

75%

Lisowski A., Grela M., Sypula M., Swietochowski A., Dabrowska-Salwin M.

Annals of Warsaw University of Life Sciences - SGGW. Agriculture

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2015

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nr 65 Agric.Forest Eng.

The aim of this study was to evaluate the fit of mathematical models for drying wet wood chunks with a length of 60 ±1 mm and a diameter of 10 ±2 mm and dry wood chips size of 40 ±10 mm obtained from the branches of fruit trees stored for a 6--months period under natural conditions. Biomass moisture was measured on a monthly basis. For moisture ratio the parameters of nine mathematical models and their statistical evaluation were developed. It was found that wet wood chunks had a large shrinkage (15%) which was probably due to the high content of soft wood tissue in the branches. During the storage of wet wood chunks the moisture decreased significantly, from 47.57 to 10.84%, and the dry chips only slightly (from 11.85 to 8.04%), and in both cases at the end of drying the biomass reached an equilibrium moisture. The best model reflecting changes moisture ratio of wet wood chunks is the Page's model, but the Wang's, Singh's and logarithmic models, may also be used for drying a moist biomass under natural conditions. Drying of dry wood chips is best represented by the logarithmic model, but for this kind of material a Page's, Wang's and Singh's, two term and Midilli's et al. models can be used. Modeling in natural conditions requires consideration of ambient conditions, especially air temperature and relative humidity.

11

Anatomy of Lebanon cedar [Cedrus libani A. Rich] wood with indented growth rings

75%

Yaman B.

Acta Biologica Cracoviensia. Series Botanica

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2007

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tom 49

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nr 1

19-23

This study examined the anatomical characteristics of indented growth rings in Lebanon cedar. In the indented pattern of growth rings, the alignment and shape of tracheids and rays were found to be irregular, and distinctive trabeculae were identified in tracheids. Multiseriate parenchymatic rays occur in addition to uniseriate and biseriate ones. In the indented pattern the average tracheid length is shorter, whereas the lumen diameter and double-wall thickness are wider than those of unindented ones. The average maximum ray height is greater than that of normal wood. The average number of tracheids per mm2 differs only in latewood.

12

The proposal of evaluation of selected thermal-degradation and environmental characteristics of wood modified treatment. Part 1: Determination of selected thermal-degradation characteristics

75%

Ruzinska E., Mitterova I., Jablonski M.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2014

|

tom 87

13

Bending creep of Maritime pine wood (Pinus pinaster Ait.) chemically modified

75%

Lopes D. B., Mai C., Militz H.

Folia Forestalia Polonica. Series A . Forestry

|

2013

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tom 55

|

nr 3

The long-term performance of a structural member is determined by its durability and deformation with time. The bending creep behaviour of modified wood was assessed experimentally over a period of 35 days (840 hours). Four chemical modification processes were used: 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU), mmethylated melamine formaldehyde resin (MMF), tetraethoxysilane (TEOS) and amid wax (WA). Wood stakes with 20.10.200 mm RTL dimensions of Portuguese Maritime pine (Pinus pinaster Ait.) from sapwood part of the stem were used for evaluated the primary creep. Experiments were conducted at bending stresses amounting to 0.1, 0.2, 0.4 of the mean immediate wood bending strength obtained at equilibrium moisture content (EMC). Applying the same stress level (SL, 0.2), wood creep was also determined at the constant low and high moisture content. As results: Between low and medium SL (8 and 16 N/mm2), unmodified wood at indoors conditions did not show any effect in the creep factors (kc). However, at high SL (35 N/mm2) a slight increase (not significant) in the kc was found. It seems that the kc was nearly independent of the SL. In the lumen fill modification (TEOS and wax), the deposited material has not affected the creep behaviour under various SL. The cell wall modification (with DMDHEU and MMF resins) did not show any differences in the kc for low and medium SL (8 and 16 N/mm2). However, resin modification under high SL (35 N/mm2) has shown a significant reduction related to unmodified wood. Between both types of resin (DMDHEU and MMF) and levels of modification (WPG), significant effect was not found. At saturated conditions, lumen fill modification (TEOS and wax) did not show any effect on creep. In the cell wall modification (DMDHEU and MMF resin), significant reduction was recorded due to the embrittlement effect imparted by the modification (deposit of resin in the cell wall).

14

Planowana wielkosc pozyskiwania drewna na Bialorusi w 2006 r.

75%

W O.

Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie

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2006

|

tom 46

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nr 1-2

85

15

Dendrolaelaps (Duplodendrolaelaps nov. subgen.) duplodens nov. spec. aus Polen (Acarina, Trichopygidiina)

75%

Wisniewski J., Hirschmann W.

Bulletin of the Polish Academy of Sciences. Biological Sciences

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1991

|

tom 39

|

nr 4

16

Technological innovations in the production of wooden pallets

75%

Lis W., Tabert M., Popyk W.

Intercathedra

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2015

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tom 31

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nr 1

A wooden pallet assembly line was evaluated according to the Oslo methodology, which was developed by the OECD and Eurostat. The line enables the assembly of EUR-pallets as well as industrial pallets, coloured pallets and PBR pallets. The technological process of production of packages is in agreement with required specifications for standardised products in European and world recommendation systems: EUR, EPAL and CHEP. Product, process, organisational and marketing innovations were evaluated.

17

Characteristic of post-consumer wood chips and particles used in particleboard production. Part I.

75%

Janiszewska D., Frackowiak I., Andrzejak C.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2014

|

tom 87

18

Foaming of polyvinylacetate adhesives - improved technologic parameters for a solid wood gluing process

75%

Sedliacik J., Schmidtova J., Smidriakova M.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2014

|

tom 87

19

Restriction of swelling of wood subjected to bending stress and moistening in the compressed zone

75%

Molinski W., Roszyk E.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

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2010

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tom 09

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nr 1

The study was undertaken to show the possibility of wood swelling pressure determination on the basis of the time course of its mechano-sorptive creep induced by bending stress of different values and simultaneous moistening of the compressed zone.The creep was induced in the conditions of three-point bending of beech wood (Fagus sylvatica L.). The bending pressure applied in the radial direction was of the magnitude of 0.05, 0.1 and 0.15 of the mean destroying stress determined for the samples of moisture content of about 7%. Immediately after application of loading the samples were subjected to asymmetric moistening in the zone of compressive stress. For the sake of comparison also the free sorptive deformation of analogous samples was observed. On the basis of the linear relations between the deformation (recorded at specific time intervals during the process of mechano-sorptive creep) and the bending stress applied, it was possible to determine the values of the stress at which the samples would remain in the non-deformed state despite their asymmetric moistening. The maximum swelling pressure determined in this way is by about 50% greater than that found in the direct way.

20

The influence of drying parameters on wood properties

75%

Baranski J., Chuchala D., Orlowski K., Muzinski T.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

|

2014

|

tom 86

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