Wood color changes and termiticidal properties of teak heartwood extract used as a wood preservative

Holzforschung ◽  
2020 ◽  
Vol 74 (3) ◽  
pp. 233-245 ◽  
Author(s):  
Victor Fassina Brocco ◽  
Juarez Benigno Paes ◽  
Lais Gonçalves da Costa ◽  
Grant T. Kirker ◽  
Sérgio Brazolin
Keyword(s):  
Color Change ◽  
Tectona Grandis ◽  
Wood Preservative ◽  
Hot Water ◽  
Natural Resistance ◽  
Color Changes ◽  
Nasutitermes Corniger ◽  
Wood Impregnation ◽  
Ethanol Extracts ◽  
Choice Feeding

AbstractThe aim of this study was to evaluate the change in colorimetric patterns and the termite resistance of light-colored and low durability wood when impregnated with teak (Tectona grandis) heartwood extractives. Hot water and ethanol extracts were obtained from 20-year-old teak heartwood and used to evaluate the influence on color change and the natural resistance of 10-year-old teak sapwood and Pinus sp. For wood impregnation, a full-cell (Bethell) treatment was conducted. To verify the influence of the teak extracts, the colorimetric patterns of wood were determined using the Munsell and CIE-L*a*b* systems. Choice and no-choice feeding tests were performed under laboratory conditions to test the efficacy of the teak extract solutions against two termite species Nasutitermes corniger and Cryptotermes brevis. All of the extract solutions promoted a significant darkening of the wood, bringing the color of the impregnated wood closer to older teak heartwood than the untreated samples of the respective species. Ethanol extracts increased the resistance and mortality against N. corniger in both choice and no-choice tests. Resistance to C. brevis was not clearly affected.

scholarly journals Comparison of Color Change to pH Range and Acid-Base Titration Indicator Precision Test of Multiple Ethanol Extracts

2021 ◽  
Vol 19 (1) ◽  
pp. 1446
Author(s):  
Lilis Tuslinah ◽  
Anna Yuliana ◽  
Dian Arisnawati ◽  
Lina Rahmawati Rizkuloh
Keyword(s):  
Color Change ◽  
Secondary Data ◽  
Ethanol Extract ◽  
Acid Base ◽  
Color Changes ◽  
Synthetic Indicators ◽  
Significant Difference ◽  
Acid Base Titration ◽  
Ethanol Extracts ◽  
Ph Range

Natural indicators using anthocyanin compounds can be an alternative to synthetic indicators on acid-base titration because anthocyanin is an organic compound that is unstable with changes in pH. The extraction was carried out with ethanol because the compounds of anthocyanin were polar. This study was to ensure an ethanol extract of some plants could be used as an acid-base indicator that had a pH range of color change and the value of the equality parameter was not significantly different from the phenolphthalein indicator. The research method is to collect research journals on making natural indicators from ethanol extracts of various plants compared to phenolphthalein indicators so that secondary data from these journals can be processed statistically. Research results and conclusions: Based on the results of statistical data processing using the t-test there was no difference in the average pH of the phenolphthalein indicator with the average pH of ethanol extracts of adam air leaves (Rheo discolor), white frangipani flowers and Clitoria teratea L., with a significance value > 0.05 and the equality test (precision) had the requirements of good equality. HIGHLIGHTS Natural indicators are needed as a substitute for synthetic indicators in determining acid-base titrations; one of them is anthocyanin dye Research journals on making natural indicators from ethanol extracts of various plants compared to phenolphthalein indicators so that secondary data from these journals can be processed statistically There was no significant difference between the average pH of the phenolphthalein indicator and the average pH of the ethanol extract of Adam's Eve Leaves, ethanol extracts of white Cambodia flowers and ethanol extracts of Telang flowers in producing color changes GRAPHICAL ABSTRACT

scholarly journals Effects of Hygrothermal Environment in Cooling Towers on the Chemical Composition of Bamboo Grid Packing

Forests ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 274 ◽  
Author(s):  
Li-Sheng Chen ◽  
Ben-Hua Fei ◽  
Xin-Xin Ma ◽  
Ji-Ping Lu ◽  
Chang-Hua Fang
Keyword(s):  
Chemical Composition ◽  
Service Life ◽  
Mass Loss ◽  
Color Change ◽  
Hot Water ◽  
Cooling Towers ◽  
Outer Skin ◽  
Glass Fiber Reinforced Plastic ◽  
Color Changes ◽  
Hygrothermal Environment

Bamboo grid packing (BGP) is a new kind of cooling packing, used in some Chinese hyperbolic cooling towers, which has excellent potential to complement or replace cooling packing made of polyvinyl chloride (PVC), cement, and glass fiber-reinforced plastic. For bamboo applications, mechanical properties and service life are matters of concern; this is strongly associated with bamboo’s chemical composition and mass loss. To better understand the mechanics of mechanical property deterioration and service life reduction, this study investigated the effects of hygrothermal environments in cooling towers on the chemical and elemental composition, mass loss, Fourier-transform infrared (FTIR) spectrum, and color changes of BGP. The results showed that BGP that had been in service for nine years in cooling towers exhibited major decreases in content of hemicellulose and benzene-ethanol extractives, as well as a significant increases in the content of α-cellulose and lignin. Exposure to the hygrothermal environment led to a decrease of oxygen content and around 8% mass loss, as well as an increase in carbon content compared to control samples. The hot water flow in cooling towers not only hydrolyzed hemicellulose, but also degraded some functional groups in cellulose and lignin. The lightness (L*) and chromaticity (a* and b*) parameters of the used BGP all decreased, except for the a* value of the outer skin. The total color change (ΔE*) of the inner skin of used BGP exceeded that of the outer skin.

scholarly journals Comparison on the Aging of Woods Exposed to Natural Sunlight and Artificial Xenon Light

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 709 ◽  
Author(s):  
Ru Liu ◽  
Hanwen Zhu ◽  
Kang Li ◽  
Zhong Yang
Keyword(s):  
Color Change ◽  
Light Exposure ◽  
Early Stage ◽  
Tectona Grandis ◽  
Sunlight Exposure ◽  
Light Sources ◽  
Natural Sunlight ◽  
Color Changes ◽  
Xenon Light ◽  
Aging Stage

To investigate the relationship between sunlight and artificial light sources on the weathering of wood, three woods, namely, Tectona grandis L.F. (teak), Stereospermum colais (mabberley), and Dicorynia guianensis (basralocus), were tested under natural sunlight for 733 days and artificial xenon light for 180 h, respectively. A comparison between sunlight and artificial xenon light was made based on surface color changes at various intervals. The results showed that the woods suffered from more severe aging in the artificial xenon light exposure than that in the natural sunlight exposure. At the early stage of exposure, very good relationships were found between 70 days under natural sunlight weathering and 60 h under artificial xenon light weathering. Compared with natural sunlight, about a 30 times faster aging process was identified in the artificial xenon light. However, the linear relationship vanished at the later aging stage. It was found that the color change fluctuated in natural sunlight, while it increased steadily in artificial xenon light. The wood species affected the aging of woods. In natural sunlight exposure, the color change decreased in the order of mabberley > teak > basralocus, while in artificial xenon light exposure, color change decreased in the order of mabberley > basralocus > teak due to the easier volatilization of extractives in artificial xenon light than in natural sunlight.

scholarly journals Study of acid-base indicator property of flowers of Ipomoea biloba

2012 ◽  
Vol 1 (12) ◽  
pp. 420-422 ◽  
Author(s):  
Sajin Kattuvilakam Abbas
Keyword(s):  
Color Change ◽  
Strong Acid ◽  
Pharmaceutical Journal ◽  
Weak Acid ◽  
Hot Water ◽  
Weak Base ◽  
Acid Base ◽  
Strong Base ◽  
Color Changes ◽  
Flower Pigments

Indicators help to determine the equivalence point in acid – base titrations (neutralization titrations). They show sharp color change with respect to change in pH. Commonly used indicators for neutralization titrations are synthetic in nature. They are found to posses hazardous effects in human body. The highly colored pigments obtained from plants are found to exhibit color changes with variation of pH. A study has been done to investigate the indicator activity of aqueous extract of flower pigments and compared with that of already existing synthetic indicators. Pigments were extracted using hot water and a definite volume was added which gave accurate and reliable results for all the four different types of neutralization titrations - strong acid against strong base, strong acid against a weak base, weak acid against strong base and weak acid against weak base. The work proved to be acceptable in introducing flower pigments as a substitute to the synthetic acid-base indicators.DOI: http://dx.doi.org/10.3329/icpj.v1i12.12452 International Current Pharmaceutical Journal 2012, 1(12): 420-422

scholarly journals Investigation of the selective color-changing mechanism of Dynastes tityus beetle (Coleoptera: Scarabaeidae)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiyu Sun ◽  
Wei Wu ◽  
Limei Tian ◽  
Wei Li ◽  
Fang Zhang ◽  
...  
Keyword(s):  
Focused Ion Beam ◽  
Color Change ◽  
Incidence Angle ◽  
Ion Beam ◽  
Three Dimensional ◽  
Water Infiltration ◽  
Photonic Materials ◽  
Local Color ◽  
Water Contact ◽  
Color Changes

AbstractNot only does the Dynastes tityus beetle display a reversible color change controlled by differences in humidity, but also, the elytron scale can change color from yellow-green to deep-brown in specified shapes. The results obtained by focused ion beam-scanning electron microscopy (FIB-SEM), show that the epicuticle (EPI) is a permeable layer, and the exocuticle (EXO) is a three-dimensional photonic crystal. To investigate the mechanism of the reversible color change, experiments were conducted to determine the water contact angle, surface chemical composition, and optical reflectance, and the reflective spectrum was simulated. The water on the surface began to permeate into the elytron via the surface elemental composition and channels in the EPI. A structural unit (SU) in the EXO allows local color changes in varied shapes. The reflectance of both yellow-green and deep-brown elytra increases as the incidence angle increases from 0° to 60°. The microstructure and changes in the refractive index are the main factors that influence the process of reversible color change. According to the simulation, the lower reflectance causing the color change to deep-brown results from water infiltration, which increases light absorption. Meanwhile, the waxy layer has no effect on the reflection of light. This study lays the foundation to manufacture engineered photonic materials that undergo controllable changes in iridescent color.

scholarly journals Characterization of Food Packaging Films with Blackcurrant Fruit Waste as a Source of Antioxidant and Color Sensing Intelligent Material

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2569
Author(s):  
Mia Kurek ◽  
Nasreddine Benbettaieb ◽  
Mario Ščetar ◽  
Eliot Chaudy ◽  
Maja Repajić ◽  
...  
Keyword(s):  
Food Packaging ◽  
Water Solubility ◽  
Color Change ◽  
Chitosan Film ◽  
Water Vapor Permeability ◽  
Vapor Permeability ◽  
Color Changes ◽  
Insoluble Particles ◽  
Polymer Stability ◽  
Food Packaging Films

Chitosan and pectin films were enriched with blackcurrant pomace powder (10 and 20% (w/w)), as bio-based material, to minimize food production losses and to increase the functional properties of produced films aimed at food coatings and wrappers. Water vapor permeability of active films increased up to 25%, moisture content for 27% in pectin-based ones, but water solubility was not significantly modified. Mechanical properties (tensile strength, elongation at break and Young’s modulus) were mainly decreased due to the residual insoluble particles present in blackcurrant waste. FTIR analysis showed no significant changes between the film samples. The degradation temperatures, determined by DSC, were reduced by 18 °C for chitosan-based samples and of 32 °C lower for the pectin-based samples with blackcurrant powder, indicating a disturbance in polymer stability. The antioxidant activity of active films was increased up to 30-fold. Lightness and redness of dry films significantly changed depending on the polymer type. Significant color changes, especially in chitosan film formulations, were observed after exposure to different pH buffers. This effect is further explored in formulations that were used as color change indicators for intelligent biopackaging.

Influence of Hydrogen Peroxide Bleaching Gels on Color, Opacity, and Fluorescence of Composite Resins

2012 ◽  
Vol 37 (5) ◽  
pp. 526-531 ◽  
Author(s):  
CRG Torres ◽  
CF Ribeiro ◽  
E Bresciani ◽  
AB Borges
Keyword(s):  
Hydrogen Peroxide ◽  
Composite Resin ◽  
Color Change ◽  
Composite Resins ◽  
Control Group ◽  
Peroxide Bleaching ◽  
Color Changes ◽  
Tukey Test ◽  
Bleaching Gels ◽  
Bleaching Treatment

SUMMARY The aim of the present study was to evaluate the effect of 20% and 35% hydrogen peroxide bleaching gels on the color, opacity, and fluorescence of composite resins. Seven composite resin brands were tested and 30 specimens, 3-mm in diameter and 2-mm thick, of each material were fabricated, for a total of 210 specimens. The specimens of each tested material were divided into three subgroups (n=10) according to the bleaching therapy tested: 20% hydrogen peroxide gel, 35% hydroxide peroxide gel, and the control group. The baseline color, opacity, and fluorescence were assessed by spectrophotometry. Four 30-minute bleaching gel applications, two hours in total, were performed. The control group did not receive bleaching treatment and was stored in deionized water. Final assessments were performed, and data were analyzed by two-way analysis of variance and Tukey tests (p<0.05). Color changes were significant for different tested bleaching therapies (p<0.0001), with the greatest color change observed for 35% hydrogen peroxide gel. No difference in opacity was detected for all analyzed parameters. Fluorescence changes were influenced by composite resin brand (p<0.0001) and bleaching therapy (p=0.0016) used. No significant differences in fluorescence between different bleaching gel concentrations were detected by Tukey test. The greatest fluorescence alteration was detected on the brand Z350. It was concluded that 35% hydrogen peroxide bleaching gel generated the greatest color change among all evaluated materials. No statistical opacity changes were detected for all tested variables, and significant fluorescence changes were dependent on the material and bleaching therapy, regardless of the gel concentration.

scholarly journals SURFACE CHEMICAL AND COLOR CHARACTERIZATION OF JUVENILE TECTONA GRANDIS WOOD SUBJECTED TO STEAM-DRYING TREATMENTS

2016 ◽  
Vol 23 (01) ◽  
pp. 1550091 ◽  
Author(s):  
ALEXANDER BERROCAL ◽  
RÓGER MOYA ◽  
MARÍA RODRIGUEZ-SOLIS ◽  
RICARDO STARBIRD ◽  
FREDDY MUÑOZ
Keyword(s):  
Color Change ◽  
Tectona Grandis ◽  
Surface Chemical ◽  
Surface Color ◽  
Teak Wood ◽  
Text Color ◽  
The Fourier Transform ◽  
Moisture Conditions ◽  
Steam Drying

The color of Tectona grandis wood is an attribute that favors its commercialization, however, wood color from fast-growth plantation trees is clear and lacks uniformity. The aim of this work is to characterize steamed teak wood by means of the Fourier transform infrared spectroscopy (FTIR) and [Formula: see text] color systems. Two moisture conditions (green and 50%) and two grain patterns (flat and quarter) of boards were analyzed through the application of different steaming times (0, 3, 6, 9, 12, 15 and 18[Formula: see text]h). The FTIR results showed that the bands at 1158, 1231, 1373 and 1419[Formula: see text]cm[Formula: see text] did not show any change with steaming, whereas the bands at 1053, 1108, 1453, 1506, 1536, 1558, 1595, 1652, 1683, 1700 and 1733[Formula: see text]cm[Formula: see text] presented a decrease in the intensity with the steaming time. The band at 1318[Formula: see text]cm[Formula: see text] was the only one that increased. Lightness ([Formula: see text]) was the most affected parameter, followed by yellowness ([Formula: see text]), while redness ([Formula: see text]) showed the smallest change. Surface color change ([Formula: see text]) presented the lowest value between 3[Formula: see text]h and 6[Formula: see text]h of steam-drying in the boards with flat grain, whereas for boards with quarter grain, the smallest [Formula: see text] value was obtained after 18[Formula: see text]h of steaming.

Comparison of the color and weight change in Paulownia tomentosa and Pinus koraiensis wood heat-treated in hot oil and hot air

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 5574-5585
Author(s):  
Intan Fajar Suri ◽  
Jong Ho Kim ◽  
Byantara Darsan Purusatama ◽  
Go Un Yang ◽  
Denni Prasetia ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Color Change ◽  
Treated Wood ◽  
Pinus Koraiensis ◽  
Weight Changes ◽  
Paulownia Tomentosa ◽  
Wood Color ◽  
Color Changes ◽  
Hot Air ◽  
Heat Treated

Color changes were tested and compared for heat-treated Paulownia tomentosa and Pinus koraiensis wood treated with hot oil or hot air for further utilization of these species. Hot oil and hot air treatments were conducted at 180, 200, and 220 °C for 1, 2, and 3 h. Heat-treated wood color changes were determined using the CIE-Lab color system. Weight changes of the wood before and after heat treatment were also determined. The weight of the oil heat-treated wood increased considerably but it decreased in air heat-treated wood. The oil heat-treated samples showed a greater decrease in lightness (L*) than air heat-treated samples. A significant change in L* was observed in Paulownia tomentosa. The red/green chromaticity (a*) of both wood samples increased at 180 and 200 °C and slightly decreased at 220 °C. The yellow/blue chromaticity (b*) in both wood samples increased at 180 °C, but it rapidly decreased with increasing treatment durations at 200 and 220 °C. The overall color change (ΔE*) in both heat treatments increased with increasing temperature, being higher in Paulownia tomentosa than in Pinus koraiensis. In conclusion, oil heat treatment reduced treatment duration and was a more effective method than air heat treatment in improving wood color.

scholarly journals Analysis of the Influence of Food Colorings in Esthetic Orthodontic Elastomeric Ligatures

2016 ◽  
Vol 10 (1) ◽  
pp. 516-521 ◽  
Author(s):  
Vanessa Dias da Silva ◽  
Eduardo Martinelli S de Lima ◽  
Caroline Dias ◽  
Leandro Berni Osório
Keyword(s):  
Color Change ◽  
Black Tea ◽  
Control Group ◽  
Distilled Water ◽  
Water Control ◽  
Color Changes ◽  
Influence Of Food

Proposition: The purpose of this study was to evaluate in vitro the color changes of esthetic orthodontic elastomeric ligatures of different shades when exposed to four food colorings commonly found in the diet of patients. Materials and Methods: The sample consisted of esthetic orthodontic elastomeric ligatures in the colors pearl, pearl blue, pearl white and colorless, which were immersed for 72 hours in five different solutions: distilled water (control group), coffee, tea, Coca-Cola ® and wine. The color changes of the esthetic orthodontic elastomeric ligatures were measured with the aid of a spectrophotometer, at T1 - as provided by the manufacturer; and T2 - after colorings process. Results: The results indicated that the esthetic orthodontic elastomeric ligatures of all initial hues are susceptible to pigmentation. Among the evaluated colors, all changed the finished look and the color of the samples tested. In ascending order, the color of the samples was as follows: distilled water, Coca-Cola®, black tea, wine and coffee. Conclusion: The substances that have a greater potential for pigmentation in esthetic orthodontic elastomeric ligatures were black tea, wine and coffee, respectively. All shades of esthetic orthodontic elastomeric ligatures are susceptible to color change.

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