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Influence of traditional wood surface modification methods on changes in aesthetic and resistance properties

Różańska Anna, Sokołek Agnieszka, Barski Adam

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

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2021

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No. 113

74--89

EN

For ages, furniture makers have been using various methods to accelerate the natural process of wood aging, in order to achieve a more sophisticated colour and to provide a uniform appearance for furniture parts replaced during restoration. Nowadays, wood aging is popular due to its aesthetic value associated with naturally aged wood, which can be enjoyed in conjunction with favourable mechanical properties of contemporary wood. Methods of wood surface modification used in wood aging can be divided into mechanical ones, consisting in changing the structure of wooden surfaces (eg. sanding, brushing, paint rubbing or structuring with chisel or other tools) and chemical ones, involving the use of chemical substances to change the colour of wood (eg. greying; application of lye, paint or wood stain; and ammonia fuming). The purpose of our study was to determine the influence of traditional wood modification techniques used in furniture-making − such as: structuring, whitewashing, rubbing, greying, dyeing with potassium permanganate solution and ammonia fuming − on the aesthetic and resistance properties of wooden surfaces (colour, gloss, roughness, abrasion resistance and resistance to scratches). Tests were performed on wood species most frequently used in Poland to produce artificially weathered wood: Scots pine (Pinus sylvestris L.) and common oak (Quercus Sp).

PL

Wpływ tradycyjnych metod powierzchniowej modyfikacji drewna na zmiany właściwości estetycznych i wytrzymałościowych. Przyśpieszenie naturalnie zachodzącego procesu starzenia się drewna stosowane jest w meblarstwie od wieków zarówno dla nadania drewnu wyszukanej barwy, jak i w celu scalenia kolorystycznego uzupełnień powstałych w procesie konserwacji mebla. Współcześnie postarzanie jest popularne ze wzglądu na walory estetyczne utożsamiane z naturalnie starym drewnem, połączone z korzystnymi właściwościami mechanicznymi jakie posiada drewno nowe. Metody powierzchniowej modyfikacji drewna podczas zabiegów postarzających dzielimy na mechaniczne polegające na zmianie struktury powierzchni drewna (np. przecieranie, szczotkowanie, bielenie czy strukturyzacja dłutem) i chemiczne czyli działanie odczynnikami, które zmieniają barwę (np. szarzenie, ługowanie, „wędzenie” drewna amoniakiem). Celem badań jest określenie wpływu tradycyjnie stosowanych w meblarstwie zabiegów modyfikacji drewna takich jak: strukturyzacja, bielenie, przecieranie, szarzenie, barwienie roztworem nadmanganianu potasu oraz wędzenie amoniakiem na estetyczne i wytrzymałościowe właściwość powierzchni drewna (barwa, połysk, chropowatość powierzchni, ścieralność i odporność na zarysowania). Do badań wykorzystano gatunki drewna najczęściej użytkowane w Polsce w celu sztucznego postarzania drewna: sosnę zwyczajną (Pinus sylvestris L.) oraz dąb (Quercus Sp).

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Climate change induced high altitude lake: Hydrochemistry and area changes of a moraine dammed lake in Leh Ladakh

Kaushik Himanshu, Ramanathan AL., Soheb Mohd, Shamurailatpam Monica Sharma, Biswal Kalyan, Mandal Arindan, Singh Chetan

Acta Geophysica

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2021

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Vol. 69, no. 6

2377--2391

EN

Himalayan glaciers are retreating, and glacial lakes are evolving and proliferating as a result of climate change. Glacier retreat marks in the formation and expansion, and sometimes outburst of moraine-dammed lakes. Lato Lake is one of the high-altitude and unexplored glacial lakes upstream of Gya-Miru village in the Leh-Ladakh region. This study is the first of its kind to assess hydrogeochemistry (HCO3−, SO4 2−, NO3 −, Cl−, F−, Ca2+, Mg2+, Na+, and K+) and studying the dynamics of a moraine-dammed lake in the Ladakh Himalayas. We observed substantial expansion of Lato Lake over the past 50 years between 1969 and 2019, and the areas of the lake have increased while the glacier area is reduced by 16.4% and 4.15%, respectively. The pH values ranging from 7.6 to 8.1 show slightly alkaline. HCO3 −, Ca2+, and SO4 2− were the most dominant ions during the study period 2018–19. The high (Ca2+ + Mg2+) and a low (Na+ + K+) ratio to the total cations show that Lato Lake receives ions from rock weathering, primarily from carbonate rocks. Gibbs and Na-Mixing plot also support the hydrogeochemistry of lake water was primarily controlled by rock weathering. HYSPILT backward trajectory model suggested that atmospheric input mainly originated from the seawater vapor transported by the summer monsoonal and westerly circulation systems. Results show that the lake has a substantial impact on the long-range transport of ocean water relative to local interferences.

3

Field trip in the Thar Desert : report

Czerniawska J., Chlachula J.

Landform Analysis

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2017

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Vol. 35

21--26

EN

The Thar Desert is a part of the arid zone of north-western India. The past geomorphic processes on its territory triggered by orogenesis and climate change generated a diversity of landforms, including structural (volcanic dykes, orogenic ridges, hamadas), denudational (pediplains, pediments, desert pavements), fluvial (alluvial terraces, gullies, gravelly plains of ancient palaeochannels), lacustrine and deltaic, transgressive marine, aeolian (sand dunes) and anthropogenic (such as fields, rock mines and playas, salinas). Ongoing desertification, mass sediment transfer and ground salinization poses major threats to the local ecosystems and occupation habitats. These negative effects are responded to by new agricultural strategies contributing to the economic sustainability of the western Rajasthan.

4

Durability assessment of building materials exposed to atmosphere agents by testing in simulated environment

Bochen J.

Architecture Civil Engineering Environment

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2013

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Vol. 6, no. 1

17--25

EN

The paper presents the idea of durability valuation of building materials and elements subjected to the influence of atmospheric environment during their exploitation based on the laboratory tests carried out with the use of climatic chambers and ageing chambers. The special ageing stand for simulating climate influences and testing of building materials is presented. The apparatus works as a rotational chamber for accelerated ageing. Samples are installed inside and are subjected to artificial climatic factors, such as: sun radiation, rain and low temperature. Moreover, the results of study on method for definition of simulated climate program in the aging chamber for an examplary are natural climate of Upper Region are commented. Additionally, the results of examplary aging and durability tests for noise barriers are presented.

PL

Artykuł prezentuje problematykę oceny trwałości materiałów i elementów budowlanych poddanych w czasie eksploatacji oddziaływaniom środowiska atmosferycznego, na podstawie testów laboratoryjnych wykorzystujących komory klimatyczne oraz komory starzeniowe. Przedstawiono klimatyczną komorę starzeniową do symulacji oddziaływań klimatycznych i testowania trwałości materiałów budowlanych. Skomentowano wyniki prac nad metodyką ustalania programu klimatu symulowanego w komorze starzeniowej dla przykładowego klimatu naturalnego Górnego Śląska. Ponadto przedstawiono wyniki przykładowych testów starzeniowych akustycznych ekranów drogowych wraz prognozą ich trwałości

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Rare Earth Element mobility in a weathering profile - a case study from the Karkonosze Massif (SW Poland)

Galbarczyk-Gąsiorowska L.

Acta Geologica Polonica

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2010

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Vol. 60, no. 4

599-616

EN

The rare earth element (REE) contents of soils were determined to study the behaviour of REE in the weathering profile. The bedrock for the soils was the Karkonosze granite. A five-step extraction scheme was conducted on six soil profiles in order to determine the ability of REE to be released to the environment. Sequential extraction indicated that the REE are mostly concentrated in the organic and Fe-Mn oxyhydroxide soil fraction. Heavy REE appear to be more leachable than light REE. The change in concentration has been determined using the Nesbitt and Markovics formula. The soils from the soil profiles are enriched in REE in comparison to the parent rock.