Effect of storage temperatures on selected wood properties after caffeine treatment

2021 ◽  
Author(s):  
Klára Kobetičová ◽  
Martin Böhm ◽  
Jana Nábělková ◽  
Kateřina Lišková ◽  
Robert Černý
Keyword(s):  
Wood Properties ◽  
Caffeine Treatment ◽  
Storage Temperatures

scholarly journals Influence of selected storage temperatures on wood properties and its biological resistance after the use of methylxanthines

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 6231-6243
Author(s):  
Klára Kobetičová ◽  
Martin Böhm ◽  
Jana Nábělková ◽  
Robert Černý
Keyword(s):  
Uv Radiation ◽  
Weather Conditions ◽  
Wood Properties ◽  
The Other ◽  
Effect Of Temperature ◽  
Biological Degradation ◽  
Stable Temperature ◽  
Biological Attack ◽  
Effects Of Temperature ◽  
Storage Temperatures

Methylxanthine’s fungicidal properties were investigated, with attention to the temperature of treatment. Caffeine and theophylline treatments of beech and spruce woods were applied for three months in the temperature range of -20 to 40 °C, simulating potential weather conditions in the European region and temperatures specific for various wood applications (cellars, wine cellars, room indoor temperatures, interior trusses). Effects of the selected temperatures were considered without the influence of the other possible factors, which have been considered in previous studies (e.g. effects of temperature in combination with other factors such as UV radiation, humidity, and chemical or biological degradation). Then, the specimens were exposed to a mix of molds and fungi for three months under controlled laboratory conditions in order to analyze a possible subsequent biological attack. The results did not show any effect of temperature of the methylxanthine treatment within the studied range on the organismal activity. Caffeine exhibited a better protective potential than theophylline and was more effective for spruce than for beech. The results indicated the suitability of caffeine for protection of spruce and spruce-based materials in interior applications at a stable temperature without significant effects of UV and humidity.

Study of the quality and antioxidant properties of tomatoes (Solanum lycopersicum L.) under different postharvest and dehydration conditions

2020 ◽  
Vol 13 (9) ◽  
Author(s):  
María Lorena Luna-Guevara ◽  
Teresita González-Sánchez ◽  
Adriana Delgado-Alvarado ◽  
María Elena Ramos-Cassellis ◽  
José Guillermo Pérez-Luna ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Rural Communities ◽  
Antioxidant Properties ◽  
Titratable Acidity ◽  
Physicochemical Characteristics ◽  
Soluble Solids ◽  
Convective Drying ◽  
Tomato Fruits ◽  
Solanum Lycopersicum L ◽  
Storage Temperatures

Objective: To study the effect of storage temperatures and dehydration conditions (solar and convective drying; SD, CD), on the quality, physicochemical parameters and antioxidant properties of tomato fruits. Methodology: The physicochemical characteristics pH, titratable acidity, soluble solids (°Bx) and color parameters (L*, a* and b*), were evaluated. The lycopene, carotenoids and antioxidant activity percentages retention of tomatoes fruits stored at 7 and 22 ° C for 5 days and subjected to SD (Temperature (T) of 67 °C and luminescence of 685 lum/sqf) and CD (T 70 °C, flow rates 0.5, 1.0 and 1.5 m/s), were analyzed. Results: The fruits reached humidities of 17 and 15% for SD and CD. The parameters pH, °Bx, L*, a*, b* were highest with 22°C and CD (1.5 m/s). The value of the carotenoids was higher in fruits stored at 7 ° C and subjected to CD (1.0 and 1.5 m/s) and SD with values of 83.85, 85.98 and 99.43%, respectively. The CD (0.5 m/s) and SD improved lycopene (94.37 and 95.14%) and the antioxidant activity with values of 73.06 and 97.21%. Implications: The application of solar dehydration depends on luminescence condition; however, it is inexpensive and environmentally friendly alternative. Conclusions: The results derived in a viable alternative for the conservation and commercialization of tomato fruits in rural communities

Methodological approaches to modeling the conditions for the formation of technological losses of oil and petroleum products due to evaporation from tanks

2020 ◽  
Vol 10 (4) ◽  
pp. 386-393
Author(s):  
Кonstantin Е. Lesnykh ◽  
◽  
Aleksey А. Korshak ◽  
Nafis N. Khafizov ◽  
Andrey A. Kuznetsov ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Petroleum Products ◽  
Quantitative Composition ◽  
Number Of Factors ◽  
Main Pipelines ◽  
Pumping Rates ◽  
Mathematical Relationships ◽  
Physical And Chemical ◽  
Storage Temperatures ◽  
And Chemical Properties

The conditions for the formation of technological losses of oil and petroleum products during transportation through the main pipelines are considered and it is established that the main sources of these losses are large and small airflows of reservoirs. The value of technological losses from evaporation from tanks depends on a large number of factors, in particular: storage temperatures, pumping rates, tank filling heights, physical and chemical properties of the transported liquid, tanks turnover. Until now, a unified approach to the procedure for determining the qualitative and quantitative composition of technological losses from the evaporation of hydrocarbons during storage has not been developed, which leads to disagreements in assessing the actual losses of energy carriers. According to the analysis, it was found that the best is the calculation method for determining the actual irrecoverable losses of hydrocarbons. Its application involves the use of mathematical relationships that describe the dynamics of evaporation of oil and petroleum products in real conditions. To establish such relationships, it is proposed to develop and implement a unit that enables simulation of the process of evaporation from tanks under various conditions and obtaining experimental data taking into account a combination of a variety of factors that affect the amount of the technological losses.

FEEDBACK OF WATER STRESS ON WOOD PROPERTIES OF TREES: EXPERIMENTS WITH MISTLETOES ON RHODODENDRON ARBOREUM SM.

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohan P. Devkota ◽  
Gerhard Glatzel
Keyword(s):  
Water Stress ◽  
Wood Anatomy ◽  
Wood Properties ◽  
Vessel Diameter ◽  
Conservation Area ◽  
Rhododendron Arboreum ◽  
Central Nepal ◽  
Inhibition Of Growth ◽  
Infected Area ◽  
Anatomical Parameters

Effects of infection by the mistletoe Scurrula elata (Edgew.) Danser, on wood properties of its common host Rhododendron arboreum Sm., were studied in the Annapurna Conservation Area of Central Nepal Himalaya. Heavy infection by mistletoes invariably causes decline of the host. Infested branches show inhibition of growth, defoliation and eventual death of branch parts distal to the site of infection. Anatomical properties of wood were compared in samples of branches proximal to the infection and in uninfected branches. The hypothesis that infection induces changes in basic wood anatomy could not be proven. Vessel density, vessel area, percentage lumen area and mean vessel diameter of the wood of infested and uninfected branches did not show any significant differences. The studied anatomical parameters were not correlated to the diameter of the host branch. These results show that infection by S. elata did not cause any changes in basic wood anatomy of its host R. arboreum. It appears that the studied anatomical parameters of Rhododendron wood are fairly stable and are not changed by stress due to infection by mistletoes. The damage to the host distal to the infected area most likely results from an insufficiency of total conductive area to supply both mistletoe and host. Unfortunately we could not determine annual conductive area increment, because R arboreum does not develop usable annual tree rings in the climate of the study area. Key words: Himalayas, mistletoe. Rhododendron arboreum, Scurrula elata, water stress, wood anatomy. Ecoprint Vol.11(1) 2004.

scholarly journals Effect of Furfurylation on Hierarchical Porous Structure of Poplar Wood

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 32
Author(s):  
Xiaoshuang Shen ◽  
Pan Jiang ◽  
Dengkang Guo ◽  
Gaiyun Li ◽  
Fuxiang Chu ◽  
...  
Keyword(s):  
Porous Structure ◽  
Value Added ◽  
Untreated Wood ◽  
Weight Percent Gain ◽  
Wood Properties ◽  
Weight Percent ◽  
Acoustic Properties ◽  
Hierarchical Porous Structure ◽  
Wood Processing ◽  
Hierarchical Porous

Some wood properties (such as permeability and acoustic properties) are closely related to its hierarchical porous structure, which is responsible for its potential applications. In this study, the effect of wood impregnation with furfuryl alcohol on its hierarchical porous structure was investigated by microscopy, mercury intrusion porosimetry and nuclear magnetic resonance cryoporometry. Results indicated decreasing lumina diameters and increasing cell wall thickness of various cells after modification. These alterations became serious with enhancing weight percent gain (WPG). Some perforations and pits were also occluded. Compared with those of untreated wood, the porosity and pore volume of two furfurylated woods decreased at most of the pore diameters, which became more remarkable with raising WPG. The majority of pore sizes (diameters of 1000~100,000 nm and 10~80 nm) of macrospores and micro-mesopores of two furfurylated woods were the same as those of untreated wood. This work could offer thorough knowledge of the hierarchical porous structure of impregnatedly modified wood and pore-related properties, thereby providing guidance for subsequent wood processing and value-added applications.

scholarly journals Hybrid Approach for Wood Modification: Characterization and Evaluation of Weathering Resistance of Coatings on Acetylated Wood

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 658
Author(s):  
Anna Sandak ◽  
Edit Földvári-Nagy ◽  
Faksawat Poohphajai ◽  
Rene Herrera Diaz ◽  
Oihana Gordobil ◽  
...  
Keyword(s):  
Service Life ◽  
Hybrid Approach ◽  
Wood Properties ◽  
Wood Products ◽  
Superior Performance ◽  
Surface Erosion ◽  
Coating Film ◽  
Chemical Treatments ◽  
Cellular Wall ◽  
Bulk Substrate

Wood, as a biological material, is sensitive to environmental conditions and microorganisms; therefore, wood products require protective measures to extend their service life in outdoor applications. Several modification processes are available for the improvement of wood properties, including commercially available solutions. Among the chemical treatments, acetylation by acetic anhydride is one of the most effective methods to induce chemical changes in the constitutive polymers at the cellular wall level. Acetylation reduces wood shrinkage-swelling, increases its durability against biotic agents, improves UV resistance and reduces surface erosion. However, even if the expected service life for external cladding of acetylated wood is estimated to be 60 years, the aesthetics change rapidly during the first years of exposure. Hybrid, or fusion, modification includes processes where the positive effect of a single treatment can be multiplied by merging with additional follow-up modifications. This report presents results of the performance tests of wood samples that, besides the modification by means of acetylation, were additionally protected with seven commercially available coatings. Natural weathering was conducted in Northern Italy for 15 months. Samples were characterized with numerous instruments by measuring samples collected from the stand every three months. Superior performance was observed on samples that merged both treatments. It is due to the combined effect of the wood acetylation and surface coating. Limited shrinkage/swelling of the bulk substrate due to chemical treatment substantially reduced stresses of the coating film. Hybrid process, compared to sole acetylation of wood, assured superior visual performance of the wood surface by preserving its original appearance.

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