New insights into the degradation processes and influence of the conservation treatment in alum-treated wood from the Oseberg collection

Hybrid nanocomposites made of diol-modified silanes and nanostructured calcium hydroxide. Applications to Alum-treated wood

Pure and Applied Chemistry ◽

10.1515/pac-2016-1014 ◽

2017 ◽

Vol 89 (1) ◽

pp. 29-39 ◽

Cited By ~ 7

Author(s):

Fabrizio Andriulo ◽

Rodorico Giorgi ◽

Calin Constantin Steindal ◽

Hartmut Kutzke ◽

Susan Braovac ◽

...

Keyword(s):

Calcium Hydroxide ◽

Structural Integrity ◽

Treated Wood ◽

Single Step ◽

Hybrid Nanocomposites ◽

Viking Age ◽

X Ray Diffraction ◽

Conservation Treatment ◽

Starting Point ◽

Gas Chromatography Mass Spectroscopy

AbstractThe alum-treated Viking Age archaeological wooden objects from the Oseberg find have undergone extensive chemical deterioration due to the original conservation treatment, based on alum salts (KAl(SO4)2·12H2O), done in the early 1900s. Today, the artifacts are highly acidic (pH≤2) and fragile; in some cases wood has almost completely lost its structural integrity. Research on conservation methods for these finds is currently underway. In the present study, organic/inorganic multi-functional ‘hybrid systems’ – using propylene glycol modified TEOS and alkaline nanoparticles (Ca(OH)2) – have been engineered to deacidify and consolidate alum-treated wood in a single step. The advantage of using silicon monomer and nano-materials as a starting point resides in their ease of penetration into the wood structure, where silicon monomers subsequently undergo polymerization. Treated samples were investigated using thermal analysis (DTG), X-Ray Diffraction (XRD), infrared spectroscopy (ATR-FTIR), SEM/EDX and Gas Chromatography Mass Spectroscopy (GC-MS). Results suggest that in addition to consolidating the wood, alkoxysilanes could act as a bridging agent between remaining lignin and calcium hydroxide nanoparticles.

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The Viscoelastic Behaviour of Waterlogged Archaeological Wood Treated with Methyltrimethoxysilane

Materials ◽

10.3390/ma14185150 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5150

Author(s):

Magdalena Broda ◽

Morwenna J. Spear ◽

Simon F. Curling ◽

Graham A. Ormondroyd

Keyword(s):

Loss Modulus ◽

Treated Wood ◽

Mechanical Analysis ◽

Viscoelastic Behaviour ◽

Archaeological Wood ◽

Conservation Treatment ◽

Resistance To Deformation ◽

Tan Δ ◽

The One ◽

Degree Of Degradation

Waterlogged wood treatment with methyltrimethoxysilane (MTMS) proved effective in stabilising wood dimensions upon drying (anti-shrink efficiency of 76–93%). Before the method can be proposed as a reliable conservation treatment, further research is required that includes the evaluation of the mechanical properties of treated wood. The aim of the study was to characterise the effect of the treatment on the viscoelastic behaviour of archaeological waterlogged elm and oak wood differing in the degree of degradation. Dynamic mechanical analysis in the temperature range from −150 to +150 °C was used for the study. To better understand the viscoelastic behaviour of the treated wood, pore structure and moisture properties were also investigated using Scanning Electron Microscopy, nitrogen sorption, and Dynamic Vapour Sorption. The results clearly show that methyltrimethoxysilane not only prevents collapse and distortions of the degraded cell walls and decreases wood hygroscopicity (by more than half for highly degraded wood), but also reinforces the mechanical strength by increasing stiffness and resistance to deformation for heavily degraded wood (with an increase in storage modulus). However, the MTMS also has a plasticising effect on treated wood, as observed in the increased value of loss modulus and introduction of a new tan δ peak). On the one hand, methyltrimethoxysilane reduces wood hygroscopicity that reflects in lower wood moisture content, thus limiting the plasticising effect of water on wood polymers, but on the other hand, as a polymer itself, it contributes to the viscous behaviour of the treated wood. Interestingly, the effect of silane differs with both the wood species and the degree of wood degradation.

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Transformation of evaluation criteria of lands withdrawn from agricultural turnover due to radioactive contamination

Melioration and Water Management ◽

10.32962/0235-2524-2020-2-23-27 ◽

2020 ◽

pp. 23-27

Author(s):

Olga Merzlova

Keyword(s):

Economic Evaluation ◽

Radioactive Contamination ◽

Chernobyl Accident ◽

Evaluation Criteria ◽

Contaminated Land ◽

Degradation Processes ◽

Agricultural Use ◽

Land Clearance

One of the measures to eliminate the consequences of the Chernobyl accident was the exclusion of highly contaminated land from agricultural use. Due to the positive dynamics of the radiation situation, the issue of land return becomes relevant. However, in the period of exclusion of these lands the land clearance degradation processes were developing. The second part of the article is devoted to the issue of economic evaluation of the expediency of land return and the mutual coordination of the results of separate stages of complex ecological and economic evaluation. The research was carried out in Mogilev branch Institute of radiology (Republic of Belarus).

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Ukrainian Chernozem Fertility Reproduction under Soil Conservation Agriculture

Agrobìologìâ ◽

10.33245/2310-9270-2020-157-1-67-79 ◽

2020 ◽

pp. 67-79

Author(s):

Yu. Kravchenko

Keyword(s):

Soil Conservation ◽

Agricultural Land ◽

Crop Yields ◽

Conservation Agriculture ◽

Instructional Materials ◽

Cultivated Plants ◽

Forest Steppe ◽

Typical Chernozem ◽

Degradation Processes ◽

Biological Potential

In Ukraine 57.5 % of agricultural land is subjected to erosion with 10–24 million tons of humus, 0.3–0.96 million tons of nitrogen, 0.7–0.9 million tons of phosphorus and 6–12 million tons of potassium lost annually. Degradation processes are also common on chernozems, which cover about 60 % of the Ukrainian territory. The aim of the research is to defi ne the most eff ective soil conservation practices and legislative decisions aimed to conservation/recovering the Ukrainian chernozem fertility. The experimental data of the agrochemical certifi cation of Ukrainian lands, data from scientifi c papers, stock and instructional materials as well as our own fi eld and laboratory studies were used. It has been established that the long-term use of deep subsurface tillage on typical chernozem increases, compared with plowing, the content of 10–0.25 mm of air-dry and water-resistant aggregates, the bulk density, soil water storages, water infi ltration rates, the content of mobile phosphorus and exchangeable potassium, pHH2O, CaCO3 stocks, the contents of humic and fulvic acids, molecular weights of humic acids – by 5.5 and 3.06 %; 0.05 g/cm3; 25.5 mm; 22.6 mm/h; 0.1 and 3 mg/100 g of soil; 0.03 pHH2O; 18 t/ha, 0.02 and 0.04 %, 91195 kDa, respectively. Fertilizers may contribute to the crop yields increase from by 60% in the Polissya, by 40 % – in the Forest Steppe, by 15 % – in the Wet Steppe, by 10 % – in the Dry Steppe and by 40 % – in the Irrigated Steppe areas. In soil-conservation rotations, the crop placement and alternation are advisable to combine with strips or hills sowing, taking into account the local relief features; soil alkalinization, applying anti-erosion structures. Ukrainian agriculture will receive additional 10–12 million tons of forage units or 20–22 % from all fodder in a fi eld agriculture under increasing 8–10 % of arable lands for intercrops. It is advisable to mulch the eroded chernozems of Ukraine depending on their texture composition: 1.3 t/ha of mulch for sandy and loamy soils, 1.9 t/ha – for sandy and 1.1 t/ha – for loamy soils. The implementation of soil conservation agriculture can minimize some soil degradation processes and improve eff ective soil properties required to realize the biological potential of cultivated plants. Key words: chernozem, degradation, fertility, soil conservation technologies, agriculture policy.

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