Properties of molding plates made with various matrices impregnated with PF and liquefied wood-based PF resins

Abstract Phenol (P) and phenol-liquefied wood (LW; Cryptomeria japonica, Japanese cedar) have been reacted with formalin and ammonium hydroxide as a catalyst to prepare alcohol-soluble phenol-formaldehyde (PF) resins named PF and LWPF, respectively. The resins prepared were dehydrated, diluted with ethanol, and impregnated into wood powders, filter papers, and cloths. The PF resin-impregnated matrix materials were then hot-pressed to form molding plates (MP) and their properties were tested. Differential scanning calorimetric (DSC) analysis shows that both PF and LWPF behave as hot-melting resins and are able to further condensation reactions to form a set resin. However, the maximal temperatures of LWPF are shifted to a higher temperature range compared with PF. MPs made with LWPF-impregnated materials have poorer performance than that of PF. However, the bending strength of MP with filter paper is 96.8 MPa, which fits the request of CNS 10559. The MPs made of filter papers have the best mechanical properties followed by MPs with wood powders and cloths.

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Synthesis and properties of resol-type phenol-formaldehyde resins prepared from H2SO4- and HCl-catalyzed phenol-liquefied Cryptomeria japonica wood

Holzforschung ◽

10.1515/hf.2011.121 ◽

2012 ◽

Vol 66 (1) ◽

Cited By ~ 5

Author(s):

Wen-Jau Lee ◽

Chen-Ling Kang ◽

Kuo-Chun Chang ◽

Yi-Chun Chen

Keyword(s):

Differential Scanning Calorimetry ◽

Bonding Strength ◽

Cryptomeria Japonica ◽

Raw Materials ◽

Phenol Formaldehyde ◽

Japanese Cedar ◽

Differential Scanning Calorimetry Analysis ◽

Scanning Calorimetry ◽

Adhesion Properties ◽

Liquefied Wood

Abstract Wood of Cryptomeria japonica (Japanese cedar) was liquefied in phenol with H2SO4 or HCl as catalysts and used as raw materials to prepare phenol-formaldehyde (PF) resins. The curing behavior and adhesion properties of resins prepared were investigated. Wood liquefied with H2SO4 as a catalyst had better liquefaction effect than that with HCl; however, the reaction of resin synthesis was hard to control due to its quickly increasing viscosity. Differential scanning calorimetry analysis shows that PF resins prepared from HCl-catalyzed liquefied wood had higher reactivity than those of H2SO4-catalyzed wood. These PF resins were employed for manufacturing three-layer plywood. The wet bonding strength of plywood prepared with resins from HCl-catalyzed liquefied wood exceeded 0.7 MPa and fulfilled the requirement of the CNS 1349 standard.

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Effects of Drying Temperatures on the Occurrence of Sticker Stain in Japanese Cedar (Cryptomeria japonica D. Don)

Forest Products Journal ◽

10.13073/fpj-d-20-00079 ◽

2021 ◽

Vol 71 (3) ◽

pp. 209-215

Author(s):

Keisuke Toba ◽

Toru Kanbayashi ◽

Tomoya Murano

Keyword(s):

Stainless Steel ◽

Fourier Transform ◽

Cryptomeria Japonica ◽

Initial Moisture Content ◽

Japanese Cedar ◽

Wood Products ◽

Moisture Migration ◽

Partial Delay ◽

Higher Temperature ◽

C 50

Abstract Sticker stain is a material defect that results from moisture migration during wood drying, often spoiling the appearance of the surface of wood products. The effect of drying temperatures on the occurrence of surface sticker stain was investigated using Japanese cedar (Cryptomeria japonica D. Don) and three types of stickers (air-dried Japanese cedar, aluminum, and stainless steel) under four drying temperatures (20°C, 50°C, 75°C, and 100°C). At lower drying temperatures, the air-dried wood sticker tended to suppress the occurrence of surface sticker stains, whereas higher temperature or metal stickers produced sticker stains with deep color. However, no definitive relation was shown between the initial moisture content and the extent of sticker stain with deep color regardless of drying temperatures. It was considered that the partial delay of drying happened around the contact area with stickers, especially in cases of metal stickers. It was also found that the use of metal stickers at higher drying temperatures induced depressions in Fourier transform infrared spectra related to the occurrence of hygrothermal conditions.

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Properties of polyurethane (PUR) films prepared from liquefied wood (LW) and ethylene glycol (EG)

Holzforschung ◽

10.1515/hf-2014-0142 ◽

2015 ◽

Vol 69 (5) ◽

pp. 547-554 ◽

Cited By ~ 9

Author(s):

Wen-Jau Lee ◽

En-Shao Kuo ◽

Chung-Yu Chao ◽

Yu-Pin Kao

Keyword(s):

Molecular Structure ◽

Tensile Strength ◽

Ethylene Glycol ◽

Cryptomeria Japonica ◽

Thermomechanical Analysis ◽

Raw Material ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Liquefied Wood ◽

Higher Temperature

Abstract The wood of Cryptomeria japonica D. Don was liquefied in ethylene glycol (EG) with sulfuric acid (H2SO4) as a catalyst at 150°C for 60 min. The liquefied wood (LW)- and EG-based polyester polyols (EG-Polyest.-ol) were synthesized by reacting LW and EG with adipic acid (AA), respectively. Polyurethane (PUR) resins were made by mixing Polyest.-ol with isocyanate. The results show that LW-Polyest.-ol is a suitable raw material for PUR. The PUR films prepared with LW-Polyest.-ol have higher tensile strength with less elongation at breaking point than that with EG-Polyest.-ol. According to dynamic thermomechanical analysis, the PUR films prepared with EG-Polyest.-ol have a homogeneous molecular structure, whereas a phase separation has been found for those made with LW-Polyest.-ol. Thermal gravimetric analysis showed that the thermal degradation of LW-PUR films only starts at higher temperature than that of EG-PUR.

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CRISPR/Cas9-mediated targeted mutagenesis in Japanese cedar (Cryptomeria japonica D. Don)

Scientific Reports ◽

10.1038/s41598-021-95547-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoshihiko Nanasato ◽

Masafumi Mikami ◽

Norihiro Futamura ◽

Masaki Endo ◽

Mitsuru Nishiguchi ◽

...

Keyword(s):

Genome Editing ◽

Cryptomeria Japonica ◽

Fluorescent Protein ◽

Japanese Cedar ◽

Targeted Mutagenesis ◽

Embryogenic Tissue ◽

Breeding Period ◽

Single Mutation ◽

Knock Out ◽

Guide Rna

AbstractCryptomeria japonica (Japanese cedar or sugi) is one of the most important coniferous tree species in Japan and breeding programs for this species have been launched since 1950s. Genome editing technology can be used to shorten the breeding period. In this study, we performed targeted mutagenesis using the CRISPR/Cas9 system in C. japonica. First, the CRISPR/Cas9 system was tested using green fluorescent protein (GFP)-expressing transgenic embryogenic tissue lines. Knock-out efficiency of GFP ranged from 3.1 to 41.4% depending on U6 promoters and target sequences. The GFP knock-out region was mottled in many lines, indicating genome editing in individual cells. However, in 101 of 102 mutated individuals (> 99%) from 6 GFP knock-out lines, embryos had a single mutation pattern. Next, we knocked out the endogenous C. japonica magnesium chelatase subunit I (CjChlI) gene using two guide RNA targets. Green, pale green, and albino phenotypes were obtained in the gene-edited cell lines. Sequence analysis revealed random deletions, insertions, and replacements in the target region. Thus, targeted mutagenesis using the CRISPR/Cas9 system can be used to modify the C. japonica genome.

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Common antigenicity between Japanese cedar (Cryptomeria japonica) pollen and Japanese cypress (Chamaecyparis obtusa) pollen, I. H-2 complex affects cross responsiveness to Cry j 1 and Cha o 1 at the T- and B-cell level in mice

Immunology ◽

10.1046/j.1365-2567.2000.00020.x ◽

2000 ◽

Vol 99 (4) ◽

pp. 625-629 ◽

Cited By ~ 8

Author(s):

I. Kingetsu ◽

N. Ohno ◽

N. Hayashi ◽

M. Sakaguchi ◽

S. Inouye ◽

...

Keyword(s):

B Cell ◽

Cryptomeria Japonica ◽

Japanese Cedar ◽

Chamaecyparis Obtusa ◽

Cell Level ◽

Japanese Cypress

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Characteristics of Phenomena in Powders Type RE2Zr2O7-Al2O3 in High Temperature Annealing Conditions

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.583 ◽

2011 ◽

Vol 312-315 ◽

pp. 583-588 ◽

Cited By ~ 5

Author(s):

Grzegorz Moskal ◽

Lucjan Swadźba ◽

Marek Hetmańczyk ◽

Bartosz Witala

Keyword(s):

High Temperature ◽

Perovskite Oxide ◽

Differential Scanning Calorimetric ◽

Test Results ◽

Dsc Analysis ◽

Annealing Conditions ◽

Before And After ◽

Influence Of Temperature On ◽

Dta Analysis ◽

Type Bond

The paper presents test results and characterizes the structural stability of powders, which form a mixture of aluminium oxide (Al2O3) and gadolinium, based on rare earth zirconates. This mixture is provided to create thermal barrier coatings (TBCs) by spraying. The purpose of the tests was to determine the influence of temperature on reactions, occurring between those powders within a temperature range from 25°C to 1500°C, while such conditions were to simulate the conditions, which occur during creation of TBCs and they give an answer to the question concerning mutual reactivity of the powders. The requirements for new materials, provided to spray the TBCs, indicate the necessity to prepare the materials, which do not show tendency towards reactions with the Al2O3, formed during oxidation of Ni (Co) CrAlY, while this reaction is of type bond coat. The tests included differential scanning calorimetric (DSC) analysis and differential thermal analysis (DTA) of powder mixtures. Diffraction analysis was also performed before and after the tests have been finished. The DSC analysis results, obtained at a range of high temperature, did not show any thermal effects, which indicate a low level of mutual reactivity of the powders. However, the DTA analysis suggests presence of such effects at temperature close to 1300°C, and it indicates the necessity to verify exactly the obtained results. Results of the XRD measurement showed that after annealing process already at 1100°C the perovskite oxide of GdAlO3 was present.

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