Wavelength-dependent photodegradation of wood and its effects on fluorescence

Abstract Apart from some strongly fluorescent wood species, the general fluorescence of wood has long been ignored. Recent studies suggest that each species has a distinct fluorescence, originating from both basic components and characteristic extractives. However, wood colour and fluorescence rapidly change upon exposure to sunlight. In this study, 288 samples of Acer pseudoplatanus, Quercus robur, Picea abies and Juglans nigra were irradiated with different bands of ultraviolet (UV) and visible (VIS) light. Photosensitivity was examined in regards of colour, infrared absorbance (FTIR), and fluorescence imaging. UV light caused strong yellowing in all examined species, mostly correlating with lignin degradation, carbonyl formation and the appearance of a broad banded fluorescence emission. VIS light above 420 nm, however, caused different, partly contradicting effects in colour and fluorescence, and did not affect lignin. J. nigra proved to be most sensitive towards VIS-induced yellowing and bleaching. The main new finding of this study is that the native long wave fluorescence of wood was strongly decreased by VIS-irradiation above 510 nm wavelength in all samples. This effect was not species-specific, probably originating from a cross-species wood component. The results have potential impacts on non-destructive image-based evaluation methods and wood identification.

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Effects of Long-Wave UV Light on Monilinia Growth and Identification of Species

Plant Disease ◽

10.1094/pdis.1999.83.1.62 ◽

1999 ◽

Vol 83 (1) ◽

pp. 62-65 ◽

Cited By ~ 48

Author(s):

A. De Cal ◽

P. Melgarejo

Keyword(s):

Short Distance ◽

Mycelial Growth ◽

Uv Light ◽

Dark Period ◽

Morphological Characteristics ◽

Potato Dextrose Agar ◽

Long Wave ◽

The World ◽

Identification Of Species ◽

Respective Species

The effect of long-wave UV/dark period on mycelial growth of 46 isolates of Monilinia sp. collected in Spain and 16 isolates collected from other parts of the world was investigated. Typical isolates of M. laxa, M. fructigena, and M. fructicola were grown in the dark and identified by morphological characteristics. Long-wave UV/dark conditions reduced the growth rates of M. laxa, M. fructigena, and M. fructicola on potato dextrose agar. All isolates of M. fructigena grew more slowly than those of M. fructicola. Typical and atypical isolates of M. fructigena and M. fructicola were placed in their respective species based on long-wave UV/dark growth rate data. M. laxa isolates were readily distinguished by the short distance from their conidium to the first germ tube branch. The involvement of different photoreceptors in photoresponses by M. fructicola and M. fructigena is discussed. Differences in mycelial growth under long-wave UV may be a useful tool to identify Monilinia spp.

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Duplex DNA barcoding allows accurate species determination of morphologically similar limpets (Patella spp.) from non-destructive sampling

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315416000813 ◽

2016 ◽

Vol 97 (7) ◽

pp. 1479-1482 ◽

Cited By ~ 1

Author(s):

Thomas J. Ashton ◽

Meriem Kayoueche-Reeve ◽

Andrew J. Blight ◽

Jon Moore ◽

David M. Paterson

Keyword(s):

Dna Barcoding ◽

Species Abundance ◽

Microscopic Analysis ◽

Cost Effective ◽

Field Studies ◽

Similar Species ◽

Species Determination ◽

Destructive Sampling ◽

Species Specific ◽

Non Destructive

Accurate discrimination of two morphologically similar species of Patella limpets has been facilitated by using qPCR amplification of species-specific mitochondrial genomic regions. Cost-effective and non-destructive sampling is achieved using a mucus swab and simple sample lysis and dilution to create a PCR template. Results show 100% concurrence with dissection and microscopic analysis, and the technique has been employed successfully in field studies. The use of highly sensitive DNA barcoding techniques such as this hold great potential for improving previously challenging field assessments of species abundance.

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Study of Iron Gall Inks, Ingredients and Paper Composition Using Non-Destructive Techniques

Heritage ◽

10.3390/heritage2040166 ◽

2019 ◽

Vol 2 (4) ◽

pp. 2691-2703 ◽

Cited By ~ 4

Author(s):

Victoria Corregidor ◽

Rita Viegas ◽

Luís M. Ferreira ◽

Luís C. Alves

Keyword(s):

Structural Information ◽

Uv Light ◽

Raw Materials ◽

Structural Characteristics ◽

Crystallinity Index ◽

X Ray ◽

Paper Degradation ◽

Iron Gall ◽

Non Destructive ◽

Non Destructive Techniques

Old manuscripts are among the most important elements of the cultural and historical heritage of ancient knowledge. Unfortunately, many of them suffer from degradation, mostly those written with iron gall inks. In the present work, a study using non-destructive techniques was designed with the aim of analyzing the elemental composition and structural characteristics of iron gall inks, reproduced in laboratory, paper and their interaction when the ink is deposited on paper, inducing the paper degradation. Proton induced X-ray emission, X-ray diffraction and Fourier-transform infrared spectroscopy provided the elemental and structural information, and photography under infrared (IR) and ultraviolet (UV) light allowed the differentiation between manufactured inks. Results show that the first step of inked paper deterioration is due to acid-hydrolysis of the cellulose and the presence of reactive Fe(II) species by reducing the crystallinity index of the paper, which is affected depending on the ink recipe and the starting raw materials. These results will be useful to future studies on ancient documents written with iron gall inks, which suffer deterioration due to ink corrosion, and to differentiate between the different paper degradation mechanisms.

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Comparative analysis of occluded branch characteristics for Fraxinus excelsior and Acer pseudoplatanus with natural and artificial pruning

Canadian Journal of Forest Research ◽

10.1139/x06-308 ◽

2007 ◽

Vol 37 (8) ◽

pp. 1414-1426 ◽

Cited By ~ 13

Author(s):

Sebastian Hein ◽

Heinrich Spiecker

Keyword(s):

Mixed Models ◽

Dominant Role ◽

Fraxinus Excelsior ◽

Radial Increment ◽

Acer Pseudoplatanus ◽

Data Set ◽

Occlusion Time ◽

Residual Variation ◽

Dead Branch ◽

Species Specific

The aim of this study was to develop models on branch characteristics for Fraxinus excelsior L. (common ash) and Acer pseudoplatanus L. (sycamore maple) based on 44 and 25 sample trees, respectively. A total of 635 ash and 334 maple branches were sampled. The data set on artificial pruning was pooled among the two species with a total of 71 branches from 16 trees. The material was used to predict (i) the time for a complete occlusion, (ii) the total radius of the occluded branch inside the trunk, (iii) the branch insertion angle, and (iv) the dead branch portion of the occluded branch. In addition, the effects of species and natural versus artificial pruning were assessed. Generalized hierarchical mixed models with univariate or multivariate approaches were used in this analysis. The diameter of the occluded branch and the stem radial increment played a dominant role as predictors. Artificial pruning led to a significant reduction in occlusion time and a shorter occluded branch radius. Only few species-specific differences were found. Simulations showed a reasonable overall behaviour of the models. The residual variation was tolerable for integrating the models into a growth simulation system.

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Performance of wood treated with prospective organic surface protectants upon outdoor exposure: FTIR spectroscopic analysis of weathered surfaces

Holzforschung ◽

10.1515/hf-2011-0247 ◽

2013 ◽

Vol 67 (2) ◽

pp. 227-235 ◽

Cited By ~ 4

Author(s):

Christoph F. Schauwecker ◽

Armando G. McDonald ◽

Jeff J. Morrell

Keyword(s):

Pinus Taeda ◽

Loblolly Pine ◽

Lignin Degradation ◽

Structural Integrity ◽

Uv Light ◽

Outdoor Exposure ◽

Water Repellent ◽

Surface Protection ◽

Alternative Materials ◽

Lignin Depolymerization

Abstract Visual appeal of wood is as important as its structural integrity in outdoor applications. Discoloration and checking of wood favor the utilization of alternative materials for outdoor cladding and decking. Lignin depolymerization is one of the critical processes leading to weathering. In the present paper, the potential of different classes of surface protection agents has been assessed on loblolly pine (Pinus taeda) impregnated with water repellents, organic UV inhibitors, and an organic biocide. The treated samples were exposed to predetermined doses of solar radiation in Eastern Oregon, and the chemical changes occurring on the surfaces were evaluated by FTIR spectroscopy. After 1-year exposure, lignin loss was complete on all surfaces; however, some treatments provided longer term protection than others. Organic UV light inhibitors were most effective in this regard. A petroleum-based water repellent with a melting point of 54–58°C also provided protection against lignin degradation.

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Synthesis of Single-Crystalline Gold Nanosheet Having Multilayer Structure under the Polymeric Bulk Condition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.548-549.301 ◽

2014 ◽

Vol 548-549 ◽

pp. 301-304

Author(s):

Sang Ho Cha

Keyword(s):

Uv Light ◽

Multilayered Structure ◽

Gold Complex ◽

Side Chain ◽

Synthetic Approach ◽

Layer Spacing ◽

Single Crystalline ◽

Long Wave ◽

Gold Precursor ◽

Homogeneous Complex

A novel synthetic approach to ultrathin (< 5 nm) multilayered single crystalline gold nanosheets using amphiphilic comb-like polymer as template was presented. The poly (oxyethylene) containing decyl-tri (oxyethylene) amphiphile as well as the thioether linking group in the side chain was synthesized via polymer analogous reaction. The polymer and the gold precursor, LiAuCl4, were mixed and dried to afford a homogeneous complex. The gold precursors were reduced to gold crystals by photoreduction using long wave UV light (> 350 nm). The gold nanosheets with multilayered structure, where the layer spacing is about 3.6 nm, were obtained after 24 h. The formation of the multilayered nanosheets is due to the layered structure of the gold complex of the polymer and precursor.

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Enhancement of UV Excited Photoluminescence by Fabry-Perot Microcavity

Journal of Spectroscopy ◽

10.1155/2015/153483 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6

Author(s):

Chunxian Tao ◽

Jun Ruan ◽

Dong Liang ◽

Zhaoxia Han ◽

Liang He ◽

...

Keyword(s):

Uv Light ◽

Resonant Cavity ◽

Fluorescence Emission ◽

Light Emitting ◽

Dielectric Mirror ◽

Fabry Perot ◽

Measurement Results ◽

Phosphor Coating ◽

Uv Visible ◽

Higher Sensitivity

A light-emitting microcavity with the structure of dielectric mirror/phosphor coating/dielectric mirror for the enhancement of PL efficiency excited under UV light was designed and fabricated. The fluorescence emission of Lumogen S0795 coating within microcavity structure is significantly enhanced compared with the coating on bare substrate. The measurement results indicate the possibility of developing front illuminated CCD based on optical resonant cavity for UV-visible imaging with higher sensitivity.

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Cytometric Analysis of the Proliferative Capacity of HUT 102 Lymphoblasts Exposed to Long-wave UV Light and Psoralen

Journal of Investigative Dermatology ◽

10.1111/1523-1747.ep12277365 ◽

1989 ◽

Vol 93 (1) ◽

pp. 96-99 ◽

Cited By ~ 7

Author(s):

Francis J. Hornicek ◽

Theodore I. Malinin ◽

Howard Gratzner ◽

George I. Malinin

Keyword(s):

Uv Light ◽

Proliferative Capacity ◽

Long Wave

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Towards new seed orchard designs in Germany – A review

Silvae Genetica ◽

10.2478/sg-2021-0007 ◽

2021 ◽

Vol 70 (1) ◽

pp. 84-98

Author(s):

Heike Liesebach ◽

Katharina Liepe ◽

Cornelia Bäucker

Keyword(s):

Native Species ◽

Random Mating ◽

Seed Orchard ◽

Tree Breeding ◽

Progeny Testing ◽

Acer Pseudoplatanus ◽

Seed Orchards ◽

Breeding Populations ◽

Estimated Breeding Values ◽

Species Specific

Abstract New first and 1.5 generation seed orchards are to be created in Germany based on recently assembled breeding populations of Acer pseudoplatanus, Larix sp., Picea abies, Pinus sylvestris, Pseudotsuga menziesii, and Quercus sp. To justify the high expenses in time and cost for orchard establishment and maintenance, planning should make use of consolidated knowledge and experience of both the national and international scientific community. Here, we briefly describe advances in genetic gains achieved through tree breeding, and resume population genetic aspects and design considerations to draw conclusions for clonal composition and spatial design of the new orchards. We conclude that to avoid outbreeding depression separate orchards are required for each breeding zone. The zones are species-specific and defined by ecological and climatic aspects. A minimum of 60-80 clones per orchard is recommended for native tree species with high proportions of natural regeneration in forest practice. This would allow future selective thinning based on estimated breeding values from progeny testing. It would also permit the transfer of seed orchard progenies into a naturally regenerating forest stands without the risk of a genetic bottleneck. Lower clone numbers are appropriate for non-native species and hybrids. It is important to strictly avoid inbreeding depression, achieved by using only one clone per progeny or population, from which the plus trees were selected. Further, the spatial layout should promote random mating by optimizing the neighbourhood of each clone. With all of these considerations taken into account, we expect superior quality traits and at least 10-15 % more volume from the new seed orchards.

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