Moisture Adsorption and Hygroexpansion of Paraffin Wax Emulsion-treated Southern Pine (Pinus spp.)

Abstract The aim of this study was to enhance the water repellency and dimensional stability of thermally modified wood by combining the preimpregnation of paraffin wax emulsion. To achieve this, Southern pine (SP; Pinus spp.) samples were first impregnated with paraffin wax emulsion (with 2.0% solid content) and then subjected to thermal modification (TM) in an oven at 180°C and 220°C for 4 and 8 h. The contact angle (CA), surface free energy, water absorption rate (WAR), anti-swelling efficiency (ASE), and bending properties of the control and modified samples were investigated. Moreover, the chemical and morphological alterations were analyzed by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Both the wax impregnation and TM decreased the surface wettability, water absorption, and tangential swelling, while the combination of wax and thermal treatment exhibited the best water repellency and dimensional stability, indicating the synergism between the two procedures. However, the wax preimpregnation did not affect the mechanical properties of thermally modified wood. The FTIR, SEM, and XPS analyses confirmed that the synergistic effect is mainly due to the redistribution of the paraffin wax during TM rather than its impact on the chemical changes caused by thermal degradation.

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Impedance spectroscopy and circuit modeling of Southern pine above 20% moisture content

Holzforschung ◽

10.1515/hf.2008.115 ◽

2008 ◽

Vol 62 (6) ◽

Cited By ~ 16

Author(s):

Samuel L. Zelinka ◽

Douglas R. Rammer ◽

Donald S. Stone

Keyword(s):

Moisture Content ◽

Low Frequency ◽

Charge Carriers ◽

Electrode Spacing ◽

Published Data ◽

Southern Pine ◽

Low Frequencies ◽

Warburg Impedance ◽

Mineral Ions ◽

Pinus Spp

Abstract Impedance spectra were collected from Southern pine (Pinus spp.) equilibrated to a moisture content 20% and a saturated condition. Cylindrical graphite electrodes were embedded in the wood so that they met nearly end-to-end along a line parallel to the grain, and impedance properties were characterized as functions of electrode spacing and electrode contact pressure at frequencies between 1×10-1 and 3×105 Hz. The data exhibit a low-frequency tail that can be fit with a Warburg element, indicative of a diffusive motion of charge carriers. Values of the Warburg impedance were compared with previously published data on molar conductivities of endogenous mineral ions in wood. The data suggest that mineral ions are the predominant charge carriers in wood at low frequencies and high moisture contents based on the strong correlation between the Warburg impedance and molar conductivities.

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Differential Expression of a Putative Copper Homeostasis CutC Gene in Fibroporia radiculosa During Initial Decay of Copper-Treated Wood

Forest Products Journal ◽

10.13073/fpj-d-20-00043 ◽

2020 ◽

Vol 70 (4) ◽

pp. 469-475

Author(s):

Katie M. Ohno ◽

Amy B. Bishell ◽

Glen R. Stanosz

Keyword(s):

Differential Expression ◽

Treated Wood ◽

Wood Decay ◽

Untreated Wood ◽

Copper Homeostasis ◽

Southern Pine ◽

Decay Fungi ◽

Wood Decay Fungi ◽

Decay Test ◽

Pinus Spp

Abstract Living organisms require copper for several cellular processes. Yet intracellular concentrations of copper must be regulated to avoid toxicity. Not much is known about mechanisms of copper regulation in wood decay fungi. However, one putative annotation for a copper homeostasis CutC gene (FIBRA_00129), found in other brown-rot wood decay fungi, has been annotated in Fibroporia radiculosa. The aim of this study was to evaluate wood mass loss and differential expression of FIBRA_00129 during initial decay of untreated and copper-treated wood by two copper-tolerant F. radiculosa isolates (FP-90848-T and L-9414-SP) compared with copper-sensitive Gloeophyllum trabeum. Untreated southern pine (Pinus spp.) and ammoniacal copper citrate treated southern pine at three concentrations (0.6%, 1.2%, and 2.4%) were used in a 4-week-long standard decay test. Results showed G. trabeum was unable to decay copper-treated wood while both F. radiculosa isolates successfully decayed southern pine at all copper concentrations. G. trabeum and F. radiculosa L-9414-SP showed no detectable FIBRA_00129 expression over the course of this study. F. radiculosa FP-90848-T showed greater FIBRA_00129 downregulation on copper-treated wood than on untreated wood (P = 0.003). Additionally, there was greater FIBRA_00129 downregulation in F. radiculosa FP-90848-T at week 3 compared with other weeks (P = 0.015). Future studies are needed to further evaluate FIBRA_00129 during the decay process to determine its potential role in copper-tolerance.

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Correlations between Grain Angle Meter Readings and Bending Properties of Mill-Run Southern Pine Lumber

Forest Products Journal ◽

10.13073/fpj-d-20-00007 ◽

2020 ◽

Vol 70 (3) ◽

pp. 275-278

Author(s):

Guangmei Cao Anderson ◽

Frank C. Owens ◽

Frederico Franca ◽

Robert J. Ross ◽

Rubin Shmulsky

Keyword(s):

Bending Strength ◽

Modulus Of Rupture ◽

Supplementary Data ◽

Southern Pine ◽

Bending Properties ◽

Grain Angle ◽

Technical Modifications ◽

Pine Lumber ◽

Pinus Spp ◽

Southern Pine Lumber

Abstract Metriguard's grain angle meter (Model 511) measures grain angle in wood by assessing permittivity. This study evaluates the correlations between grain angle meter readings and bending properties of 1,400 kiln-dried 2 by 4 specimens of southern pine (Pinus spp.) lumber and considers its utility for providing supplementary data for predicting the strength of lumber. The results showed that in mill-run lumber, the correlation between grain angle and modulus of rupture (MOR) was −0.420. In addition, in graded lumber, the correlation between grain angle and MOR got progressively stronger as the grade went down. With a few technical modifications, applying this device in a mill production setting could prove useful for supplementing other nondestructive methods for assessing bending strength in lumber.

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Characterizing Star-sawn Pattern–Produced and Orthogonally Glued Specimens of Southern Pine

Forest Products Journal ◽

10.13073/fpj-d-18-00031 ◽

2019 ◽

Vol 69 (1) ◽

pp. 53-60

Author(s):

Guangmei Cao ◽

Rubin Shmulsky ◽

Ming Liu ◽

Edward D. Entsminger ◽

Brian K. Via ◽

...

Keyword(s):

Shear Strength ◽

Dimensional Change ◽

Good Alternative ◽

Glue Line ◽

Wood Failure ◽

Formaldehyde Resin ◽

Southern Pine ◽

Resorcinol Formaldehyde ◽

Lower Shear ◽

Pinus Spp

Abstract In this study, triangular specimens of southern pine (Pinus spp.; SP) generated by a star-sawn process were characterized according to knots and deformation. SP specimens were used to understand the differences among glue-line combinations of radial-to-radial, radial-to-tangential, and tangential-to-tangential faces bonded with phenol resorcinol formaldehyde resin. The specimens were tested for shear strength, dimensional stability, wood failure, and delamination rate in accordance with ASTM D1037 and D2559 standards. Among the star-sawn triangular samples studied, bows in tangential-face sections occurred the most. The radial-face sections of SP triangular specimens had more knots but a much lesser degree of deformation than the tangential-face sections. The tangential-to-tangential face glue-line samples showed a lower shear strength, more wood failure, and a greater tendency of delamination and dimensional change, especially when subjected to wet conditions. Confocal microscopic pictures revealed that the tangential-to-tangential glue line showed a greater tendency of deformation in the earlywood part and helped to explain the reason for poor glue-line durability and low shear strength. This article revealed that the star-sawn–process generated wood radial-face samples were more stable than others tested and are perhaps a good alternative for massive panel manufacturing.

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Southern Pine Coneworm, Dioryctria amatella (Hulst) (Insecta: Lepidoptera: Pyralidae)

EDIS ◽

10.32473/edis-in600-2004 ◽

1969 ◽

Vol 2005 (3) ◽

Author(s):

James R. Meeker

Keyword(s):

Insect Pests ◽

Southeastern United States ◽

Seed Orchard ◽

Cooperative Extension Service ◽

First Year ◽

Southern Pine ◽

University Of Florida ◽

Lepidoptera Pyralidae ◽

Second Year ◽

Pinus Spp

The southern pine coneworm, Dioryctria amatella (Hulst), also commonly referred to as a pitch moth, is consistently one of the most damaging insect pests of pine seed orchard crops throughout the southeastern United States (Ebel et al. 1980). Less well-recognized is that this widespread and frequently occurring insect also attacks a variety of other parts of pines (Pinus spp.) besides cones. Caterpillars can be found feeding on and in buds, male and female flowers, shoots, branches and stems of all ages and sizes, as well as in conelets (i.e., first-year cones) and second- year cones (Ebel 1965, Ebel et al. 1980, Goolsby et al. 1972). This document is EENY-325 (originally published as DPI Entomology Circular 393), one of a series of Featured Creatures from the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published: May 2004. EENY325/IN600: Southern Pine Coneworm, Dioryctria amatella (Hulst) (Insecta: Lepidoptera: Pyralidae) (ufl.edu)

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Effect of Multiple Leaching Cycles on Decay Resistance of Micronized Copper Azole–Treated Southern Pine Sapwood

Forest Products Journal ◽

10.13073/fpj-d-19-00065 ◽

2020 ◽

Vol 70 (2) ◽

pp. 178-181

Author(s):

Guoqi Xu ◽

Jed Cappellazzi ◽

Matthew J. Konkler ◽

Jeffrey J. Morrell

Keyword(s):

Decay Resistance ◽

Southern Pine ◽

The Past ◽

Weight Losses ◽

Fungal Attack ◽

Copper Leaching ◽

Average Block ◽

Pinus Spp ◽

Copper Azole ◽

Copper Losses

Abstract Copper remains one of the key biocides for protecting timber in soil contact. Historically, copper-based preservatives relied on solubilized copper. Over the past decade, micronized copper systems have largely replaced soluble copper systems in this application. While micronized copper chemistries have been shown to perform well over time with reduced copper leaching compared to solubilized copper, data are lacking on the effects of repeated leaching cycles on resistance of the timber to fungal attack. The potential effects of repeated leaching cycles of micronized copper azole–treated southern pine (Pinus spp.) blocks on both copper losses and resistance to fungal attack were explored over 20 leaching cycles using Gloeophyllum trabeum and Rhodonia placenta as test fungi. Copper losses during leaching were elevated for the first two cycles and steadily declined with additional cycling. There were no noticeable differences in fungal-associated weight losses in blocks exposed to G. trabeum. There was only a slight increase in average block weight losses with R. placenta, although blocks exposed to this fungus experienced higher weight losses with increased leaching cycles. The results suggest that repeated leaching exposures may produce some localized increases in susceptibility to fungal attack, but the overall effects were minor.

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Speciation of arsenic and chromium in the leachate from chromated copper arsenate (CCA) type C treated southern pine (Pinus spp.)

Holzforschung ◽

10.1515/hf.2005.031 ◽

2005 ◽

Vol 59 (2) ◽

pp. 199-204 ◽

Cited By ~ 1

Author(s):

Weining Cui ◽

Lisveth Flores del Pino ◽

Thomas C. Voice ◽

Karen Chou ◽

D. Pascal Kamdem

Keyword(s):

Treated Wood ◽

Chromated Copper Arsenate ◽

Exchange Chromatography ◽

Southern Pine ◽

Total Chromium ◽

Flame Atomic Absorption Spectroscopy ◽

Flame Atomic Absorption ◽

Type C ◽

Pinus Spp ◽

Copper Arsenate

Abstract A 558-h laboratory leaching test (AWPA E-11) was carried out on both commercially and laboratory chromated copper arsenate (CCA) type C-treated southern pine. Arsenic, chromium, and copper concentrations in the leachate collected were examined. Leaching of chromium and copper from CCA-treated wood cubes were nearly undetectable using flame atomic absorption spectroscopy after 174 and 366 h, respectively. Less than 10% of the total chromium in the leachate was present as hexavalent chromium [Cr(VI)] after leaching for 30 h. Selective ion-exchange chromatography was used to speciate arsenic in the leachate. In the first 270 h, approximately 70–90% of the total arsenic in the leachate was inorganic pentavalent arsenic [As(V)] and 10–30% was inorganic trivalent arsenic [As(III)].

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Propriedades mecânicas de peças com dimensões estruturais de Pinus spp: correlação entre resistência à tração e classificação visual

Revista Árvore ◽

10.1590/s0100-67622009000400017 ◽

2009 ◽

Vol 33 (4) ◽

pp. 741-750 ◽

Cited By ~ 3

Author(s):

Juliano Fiorelli ◽

Antônio Alves Dias ◽

Bruno Coiado

Keyword(s):

Southern Pine ◽

Para Determinar ◽

Pinus Spp

A redução da disponibilidade de espécies de madeiras nativas e seus efeitos na economia, associada ao fortalecimento dos conceitos de preservação ambiental, criou a necessidade de desenvolvimento de alternativas viáveis para utilização racional de espécies de reflorestamento. E uma das opções é a realização de classificação visual das peças. Autores de trabalhos desenvolvidos nessa linha de pesquisa verificaram a adequação das regras de classificação visual do Southern Pine Inspection Bureau (SPIB) dos EUA à madeira de Pinus do Brasil e apresentaram proposta para normalizar o processo de classificação visual dessa madeira. Nessa classificação, os aspectos com maior influência são: presença de nós, desvio de grã em relação ao eixo da peça e densidade de anéis de crescimento. Assim, esta pesquisa apresenta um estudo experimental que consistiu na classificação visual e determinação da resistência à tração de 85 peças de Pinus spp e um estudo teórico, que propôs uma equação para determinar a resistência à tração média de peças estruturais em função da classificação visual. Com este trabalho, foi possível observar a influência dos nós e dos anéis de crescimento sobre a resistência à tração das peças analisadas.

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