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EN
Experiments were conducted with the aim of improving the surface properties of Oriental beech (Fagus orientalis Lipsky) wood after weathering, including colour, gloss, and roughness, by means of heat treatment with waste olive oil (WOHT). First, WOHT was applied at 200 ℃ and 230 ℃ for 2 and 4 hours. Then, for three months, Oriental beech specimens were exposed to the weather in the Muğla region (Southern Aegean, Türkiye). After weathering, colour, gloss, and roughness tests were performed according to the ASTM D1536-58T (1964), ASTM D 523-14 (2018), and DIN 4768 (1990) standards, respectively. All treatment groups except the control group were found to have positive ΔL* values after weathering. The values of total colour change (ΔE*) for WOHT Oriental beech were better than for the unheated (control) group. The best colour stability was obtained for WOHT Oriental beech heated at 200 ℃ for 4 hours. The glossiness of all specimens decreased after weathering, but the gloss results for WOHT Oriental beech were better than those obtained for the unheated (control) group. Lower temperatures and durations of heat treatment resulted in smaller decreases in the gloss of WOHT Oriental beech on weathering. The roughness of all specimens was increased by weathering, but lower roughness values after weathering were obtained for WOHT Oriental beech than for the control group.
EN
Linden wood is used in the making of musical instruments, agricultural hand tools, and in the furniture sector. In this study, the changes in glossiness (parallel (//) and perpendicular (⊥) to the fibers at 20o, 60o, and 85o), the pull-off adhesion test, color parameters (CIEL) and pendulum hardness (König method) of two different UV curable varnishes applied to linden (Tilia tomentosa Moench.) according to industrial application techniques and exposed to artificial weathering were investigated. According to the research results, while L*, ΔH*, and ho decreased with increasing weathering time in both varnish layers, ΔC*, b*, ΔE*, a*, and C* rose. The pendulum hardness grew for Method B but dwindled for Method A. A decrease was found in the adhesion tests for both varnish methods after artificial weathering. The glossiness was generally reduced due to artificial weathering for all the angles and for both directions, with the exception of 85º in Method A. The variance analysis and homogeneity groups showed that the changes in the adhesion, pendulum hardness, L*, a*, ho, C*, perpendicular and parallel to the fibers for 60o and 85o were found to be significantly different with artificial weathering for both methods.
EN
Soil development in burning coal-mining waste heaps is a rarely addressed phenomenon, especially in Poland and in relation to pyrometamorphic substrates. Eight samples were collected from 5 heaps, four of them obtained from Europe‘s highest “Szarlota” heap located in Rydułtowy. Traces of pedogenesis were observed in both thermally changed (pyrometamorphic) and megascopically unchanged substrates. Grain size distribution is variable, with the finest silt being most clearly associated with distinct, though modest, trace element (TE) enrichment, primarily of Sb, As and Pb, and Ba and Cu. Slight variations in soil mineralogy occur even in samples derived from various parts of the “Szarlota” heap. Goethite, however, is a frequent component in most samples studied; it is an important pedogenesis factor in the soils studied and seems to be correlated with salinity. To some extent, it also influences TE composition. Relatively invariable pH, moderate TE and nutrient contents, and a lack of Alw allows vegetation growth at most of the locations studied.
EN
This study evaluated some properties of sesenduk (Endospermum malaccense) wood treated with propionic anhydride and exposed to outdoor conditions for up to one year. Defect-free samples of sesenduk were extracted with a 3:1:1 (v/v) mixture of toluene, ethanol and acetone for 3 hours at a temperature of 100°C. The samples were then modified at the same temperature for another 3 hours using propionic anhydride and 10% sodium formate as catalyst. Modulus of elasticity (MOE), modulus of rupture (MOR) and parallel-to-grain compression strength of the samples exposed to weathering were tested. Chemical treatment reduced the MOE but slightly increased the MOR and parallel-to-grain compression strength compared with untreated samples. However, treated samples retained higher strength properties than untreated ones. The modulus of elasticity, modulus of rupture and parallel-to-grain compression strength of treated samples at radial orientation were respectively 20%, 31% and 62% higher than those of untreated samples after one year’s outdoor exposure. Weathering adversely influenced the surface quality of the specimens for all exposure times.
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).
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.
7
Content available remote Schmidt hammer exposure dating for brick masonry
EN
This research investigates the validity of the Schmidt hammer exposure dating (SHED) technique as a complementary means to date monuments according to the evaluation of the brick decay from masonry exposed to climatic conditions. The degree of surface weathering, I5 (%) is calculated as an indicator of the ageing effect and compared to the absolute age of the churches constructed between 1600 and 1795. This paper discusses the results obtained with such a method and the use of the technique within the framework of historical research. Tests were done on exterior church walls built between the 17th and 19th centuries. All the churches were located within the limited geographical area of Hainaut, in the south of Belgium. Results indicate that SHED provides encouraging results for buildings constructed between 1790 and 1895, with a linear correlation (R2>0.8) between surface weathering of brick façades and their ages. However, the weathering indices show high variability of values for the period 1750−1790, which may confirm that the variable qualities of bricks were in use during this period of time because of the different production techniques. As such, the results highlight the probable influence of the entire manufacturing and construction process and technical improvements in traditional brick-making.
EN
In this study, pine and beech sapwood samples coated with 12 different waterborne acrylic resin coating systems were exposed to natural weathering in Trabzon, Turkey. The natural weathering test continued for 18 months. In these coating systems, water in different proportions, boric acid, two different acrylic resins and three different UV absorbers supplied by BASF were used. The aim was to compare the durability of 12 different coating systems in natural weathering in terms of colour change, surface roughness and macroscopic evaluation. These test methods were used to evaluate the appearance and physical properties of the coatings after the natural weathering test. The results led to the selection of the best coating formulation for wood durability in natural outdoor conditions. The appearance and physical values after 18 months of the weathering test showed that boric acid increases the durability of the coating for use in outdoor conditions. Additionally, the coating formulation containing especially acrylic resin and Tinuvin 400 DW provided the highest durability against outdoor conditions.
EN
The study area is located within the Silesia-Cracow zinc-lead ore district. Secondary minerals were collected from the reclaimed zinc-lead underground mine in Bolesław and from the currently operated zinc-lead underground mine Olkusz-Pomorzany. The main goal of investigations was the geochemical and mineralogical comparison of weathering zone developed within horst and tectonic graben. Semi-quantitative chemical composition was determined using the SEM-EDS method and quantitative chemical composition was determined employing the EMP microanalysis. Mineralogical investigations were performed with the XRD. The predominant zinc mineral of weathering zone located within tectonic horst is hemimorphite. No primary and secondary lead minerals were observed in this zone. In contrast, the weathering zone within tectonic graben contains secondary carbonate zinc and lead minerals. These differences could result from pervasive sulfide minerals (especially marcasite) in a graben unit, and limestones which are the main gangue rock of this zinc-lead ore.
EN
Metallic phases (sulphides, metallic compounds and metals), constitute critical components of metallurgical slags as they concentrate most of the potentially toxic metals occurring within smelting wastes. For this reason, a detailed characterization of the metal-rich phases is crucial for proper estimation of environmental threat resulting from slags deposition. Metallic phases observed in slags were transformed from the original ore minerals during metal smelting, and they constitute an interesting field for observations of sulphides and metals susceptibility to temperature and chemistry changes. In this study, we observed that compositions similar to sulphide minerals (e.g. bornite, chalcocite, pyrrhotite) are common, but they always appear in specific sets. We distinguished 3 general types of metallic phases: copper-iron-sulphur (among which the following subtypes appear: bornite-pyrrhotite, chalcocite, and chalcopyrite, all ofthese with various exsolutions), metallic copper and iron-phosphorous (Fe-P) type. Among all the distinguished types, Fe4Pproved to be most resistant to weathering whereas the Cu-Fe-S assemblage was altered strongly when not surrounded by glass or crystalline phases. Observations revealed that iron-rich metallic phases tended to appear in amorphous slags and copperrich phases occurring within crystalline samples.
11
Content available remote Odporność wyrobów z kompozytów polimerowo-drzewnych na czynniki środowiskowe
PL
W artykule przedstawiono wyniki badań odporności wybranych wyrobów z kompozytów polimerowo-drzewnych na działanie czynników środowiskowych. Badaniom poddano deski tarasowe wykonane z trzech rodzajów kompozytu: PVC i mączki drzewnej, PEHD i włókien bambusowych oraz PEHD i mączki drzewnej. Wyroby poddano działaniu wody, po którym określono absorpcję wody i zmiany wymiarów. Przeprowadzono także cykle hydrotermiczne i ustalono ich wpływ na wytrzymałość na zginanie. Określono także zmianę barwy po działaniu światła UV. Badane wyroby wykazały absorpcję wody na poziomie do 8%. Zmiany długości i szerokości nie przewyższyły 0,6%, zaś grubości 5%. Wytrzymałość na zginanie desek po cyklach hydrotermicznych kształtowała się powyżej 80% wartości wyjściowej. Zmiana barwy nie przekroczyła 8 jednostek.
EN
This article presents the results of research on weathering resistance of selected products made of wood-plastic composites. The tests were carried on decking profiles, made of three kinds of composites: PVC and wood flour, PEHD and bamboo fibres, PEHD and wood flour. The products were dipped into the water, afterwards water absorption and dimensional changes were analysed. Hydrothermal cycles were conducted to establish the impact to bending strength. Colour changes after the UV radiation were also tested. The tested solutions exhibited water absorption up to 8%. The length and width changes did not exceed 0.6%, and thickness 5%. The bending strength after hydrothermal cycles was above 80% compared with basic value. The colour change was below 8 units.
12
Content available Field trip in the Thar Desert : report
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.
EN
The study of the geochemical composition of sediments was undertaken to evaluate the degree of weathering and appraise the relative proportion of mafic and felsic rock materials being transported from source to sink. Thirty-three surface sediment samples collected from the creeks were used for particle size and chemical analyses. An inductively coupled plasma-Mass Spectrometer was used to determine the elemental composition of the sediments. The clay dominated Yewa and western Badagry creeks gave evidence of higher average concentrations of Ni, Sr, Y, Nb, Sc, Co, V, and Th than the eastern end of segment of Badagry Creek. The data generated from elemental ratios such as Al 2 O 3 /TiO 2, TiO 2 /Zr and binary plots of Th/Sc-Cr/Sc, Th-Sc, Y/Ni-Cr/V, TiO 2 -Zr and ICV-CIA (index of compositional variability against chemical index of alteration) showed that source sediments are composed of upper and lower crustal compositions. Also, the creeks were marked by their variation in terms of the proportion of felsic and mafic components. For instance, Yewa and western Badagry creeks are more enriched in mafic constituents, whereas the enrichment of felsic materials is significant at the eastern end of Badagry Creek. Inferring from the chemical index of alteration and plagioclase index of alteration (PIA), the Yewa and western Badagry creeks have been moderately to intensely weathered and incipient weathering was identified in the eastern end of Badagry Creek.
EN
This study concerns the modeling potential of slopes development with use of numerical stability calculations. Boundary conditions of performed numerical simulations are according to morphological and geological engineering conditions of the flysch slope shaped by weathering and surface mass movements. The multilaminate material model was used in order to imitate shale spatial variation in weathering zones. Furthermore, X-ray computed microtomography technique enabled for visualization of varied condition of shear surface extortion, which cause physical and strength parameters diversity. Calculation outputs show that geometry and location of deformation zones are affected by a model input strength parameter. The presented results confirm utility of numerical modeling as important aspect in the investigation and verification of spatiotemporal slope development cycle.
15
Content available remote Analysis on the efficiency of stone consolidation actions
EN
In this study the effectiveness of stone consolidation actions was analysed on two German sandstones with different binders, the Baumberger (calcareous) and Sander (clayey). Due to varying treatment procedures the investigated sandstones showed different petrophysical and mechanical properties.
PL
W artykule przedstawiono analizę skuteczności konsolidacji piaskowców na przykładzie dwóch niemieckich piaskowców zawierających różne materiały wiążące – piaskowce Baumberger (wapnisty) oraz Sander (marglisty). Zależnie od zastosowanej obróbki badane piaskowce wykazywały różne właściwości petrofizyczne oraz mechaniczne.
EN
In this paper we present the results of investigation of micro- and nanoscale degradation of a sheet moulded composite exposed to simulated solar radiation. Utilization of high resolution methods such as atomic force microscopy, optical profilometry and microcomputer tomography allowed us to provide the evidence of significant deterioration of the surface as well as the material few microns in depth. Additionally, the typically used macroscopic investigations, such as wettability and flexural strength, were performed to observe the impact of weathering process. It was also shown that high resolution techniques provide superior sensitivity of the material degradation detection. The particular effectiveness of the applied approach was related to the structure of investigated material, as due to its degradation, a number of voids appeared, causing a significant roughness increase. In addition, the impact of light radiation could be compared to other environmental conditions maintained in the climatic chamber. It should be underlined, that according to our knowledge, such a study has not been performed so far.
EN
Sparry limestone, ferruginous muddy limestone and limestone breccia have been found in the Western Tatra Mts. They occur within Jurassic rocks of the Choč Nappe just below red conglomerates of probable Eocene age. The deposits found bear strong resemblance to the infill of subterranean karst forms. They differ significantly from Quaternary karst deposits of the Tatra Mts. The δ18O values of spelean carbonates suggest crystallisation at relatively high temperatures (over 20°C) whereas their relatively negative δ13C values imply the presence of soil-derived CO2 linked with vegetation dominated by C3 pathway plants. The karst forms and their infill were formed before the Eocene transgression, which shows unequivocally that the Tatra Mts. were subjected to karstification at that time.
EN
The paper presents the use of selected non-destructive testing methods for the purpose of specifying information on weathering and cracking of surface layers of granite rock massif in the medieval Jeroným Mine (the Czech Republic). This mine has been declared the National Heritage Site of the Czech Republic and its opening as a mining museum to the public is gradually prepared. Geological and geomechanical evaluation documents the possibility to find all kinds of weathering grades of rock massif in this mine. Two non-destructive methods have been tested, namely the measurement of ultrasonic pulse velocity and the measurement of Schmidt hammer rebound value. Field measurements were performed in two selected galleries to verify the application of such methods in specific conditions of underground spaces. Used mining method is one of the parameters later influencing cracking of rock massif. In selected galleries, two different mining methods were used which means that a part of a gallery profile was mined out by hand tools in the Middle Ages and another part of the profile was later mined out by blasting. Measurements in these galleries have enabled to analyse the influence of used mining methods on cracking of rock massif in the impaired zone, and, consequently, on ongoing weathering processes in those zones.
PL
W pracy omówiono wykorzystanie wybranych metod nieniszczących w celu zebrania szczegółowych danych na temat wietrzenia skał i pękania warstw powierzchniowym w masywie skał granitowych w średniowiecznej kopalni Jeronym (Republika Czeska). Kopalnia ta została wpisana listę obiektów dziedzictwa narodowego w Republice Czeskiej, obecnie trwają przygotowania do jej otwarcia jako muzeum górnictwa, dostępnego dla zwiedzających. Analizy danych geologicznych i geochemicznych potwierdzają możliwość postępującego wietrzenia masywu skalnego. Przetestowano dwie metody nieniszczące: pomiar prędkości impulsu ultradźwiękowego oraz pomiarów reakcji po odskoku po uderzeniu młota Schmidta. Badania terenowe przeprowadzono w dwóch chodnikach w kopalni w celu weryfikacji metod zastosowanych w szczególnych warunkach przestrzeni podziemnych. Wybór metody wydobycia jest podstawowym czynnikiem warunkującym powstawanie spękań górotworu. W wybranych chodnikach zastosowano dwie różne metody wydobywania: w jednej części urabianie odbywało się za pomocą narzędzi ręcznych stosowanych w Średniowieczu, w części drugiej urabianie prowadzono przy wykorzystaniu prac strzałowych. Pomiary wykonane w obydwu chodnikach umożliwiły zbadanie wpływu metody wybierania na pękanie górotworu w sąsiadujących strefach, a także na postępujące procesy wietrzenia skał w tych rejonach.
EN
In some cases, in the initial stages of exposure to atmospheric conditions, gray discoloration appears on the surface of PVC products pigmented with titanium white. The aim of the study was to develop a simple method for determining the likelihood of discoloration of a PVC /thermal stabilizer / titanium white composition at the onset of exposure to UV radiation. Common thermal stabilizers were used to determine which of them, combined with a polymer and TiO2, can cause discoloration of the samples when exposed to UV radiation, especially in the presence of water. It has been shown that discoloration of a PVC composition surface exposed to UV radiation occurs only in the case of lead stabilizers. Discoloration did not occur when tin stabilizers and Ca/Zn were used in the PVC compositions. Only areas exposed to H2O during exposure to UV radiation were affected.
PL
W niektórych przypadkach na powierzchni wyrobów z PVC pigmentowanych bielą tytanową w początkowym etapie ekspozycji w warunkach atmosferycznych, pojawiają się szare przebarwienia. Niniejsza praca miała na celu opracowanie prostej metody określenia prawdopodobieństwa wystąpienia szarzenia kompozycji PVC/stabilizator termiczny/biel tytanowa w początkowym etapie ekspozycji na działanie promieniowania UV. Wykazano, że szarzenie powierzchniowe kompozycji PVC pod wpływem działania promieniowania UV, występuje jedynie w przypadku zastosowania stabilizatorów ołowiowych. Zjawiska tego nie stwierdzono w przypadku stosowania w kompozycjach PVC stabilizatorów cynowych jak również Ca/Zn. Szarzeniu ulegają jedynie miejsca mające kontakt z H2O podczas napromienienia UV.
EN
The paper presents new data on the weathering zone in Miedzianka, Holy Cross Mountains (Poland), including macroscopic, microscopic and chemical investigation, using scanning electron microscope (SEM) with energy dispersive spectrum (EDS). The deposit contains sulphide mineralization (e.g. chalcopiryte, chalcocite), and carbonates with hydroxyl (malachite and azurite) in the weathering zone. Additionally, arsenic – bearing sulphosalts of the tennantite – tetrahedrite group and Ba-sulphate were found. Moreover, cracks are observed on a macro- and micro-scale, filled with new minerals that formed during the weathering.
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