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Ramzy, Hamed, Kazzi Yolla, and Awada Houssein. "Phenolic Foam Reinforced by Cedar's Resin." Chemical Science International Journal 19, no. 1 (2017): 1–6. https://doi.org/10.9734/CSIJ/2017/33377.
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Recently phenolic foams have been received much attention because of their excellent properties including flame resistance, low density, high thermal stability over a broad temperature range and low generation of toxic gases during combustion. Cedar resin was used as a toughening agent to modify the brittleness of phenolic foam. The cedar resin was first introduced to the phenol formaldehyde resin. The mixture was successfully used to prepare phenolic foam using appropriate combinations of flowing agent. Benzene Sulfonic acid was employed as a curing agent. Orthophosphoric acid and nonionic surfactant polyoxyethylene were used as foaming agent and surfactant respectively. The mechanical properties results showed that the incorporation of cedar resin into phenolic foam dramatically improved the compressive strength indicating the excellent toughening effect of cedar resin. In addition this property is depended to the percentage of the cedar resin. The apparent density data indicated that the addition of cedar resin can increase the apparent density of phenolic foam.
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De Moraes Gomes Pereira, Maria Aparecida, Maria José Alves de Oliveira, Larissa Otubo, Vagner Fernandes, and Pablo Antônio Salvador Vasquez. "Restoration of culturally significant wooden artifacts using gamma radiation curable polyester resins." Brazilian Journal of Radiation Sciences 12, no. 4A (Suppl.) (2025): e2653. https://doi.org/10.15392/2319-0612.2024.2653.
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The preservation of cultural artifacts, particularly those made of wood, is a significant concern for conservators due to their susceptibility to damage from xylophagous organisms, fungi, and bacteria. This study investigates the use of gamma radiation to cure polymeric resins for the consolidation of three wood species: cedar (Cedrela spp.), canafistula (Peltophorum dubium), and ivorywood (Balfourodendron riedelianum). Various resins, including polyester LP 8847® combined with styrene, were subjected to gamma radiation to induce cross-linking without the need for catalysts. The results demonstrated that gamma radiation effectively cured the resin, filling wood pores and enhancing structural integrity. The analysis of apparent density showed that cedar, canafistula, and ivorywood exhibit different absorption capacities, with cedar absorbing the most resin and canafistula the least. Optical and Scanning Electron Microscopy confirmed the efficient penetration of resin into the wood samples, indicating that gamma radiation can be a viable technique for wood consolidation and protection against degrading agents
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Messier, Christian, and James P. Kimmins. "Growth of western red cedar seedlings in relation to microtopography, forest floor nutrient status, and fireweed and salal on clear-cut sites in coastal British Columbia." Canadian Journal of Forest Research 22, no. 3 (1992): 273–78. http://dx.doi.org/10.1139/x92-036.
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The growth of western red cedar (Thujaplicata Donn) seedlings was studied in relation to microtopography, to forest floor nutrient status, and to fireweed (Epilobiumangustifolium L.) and salal (Gaultheriashallon Pursh) abundance on 4-year-old logged and burned sites dominated by salal on northern Vancouver Island, British Columbia. These relationships were sought to determine some possible factors at the microsite level that influence the growth of western red cedar on recently clear-cut sites. Western red cedar growth and fireweed abundance and height were significantly greater in depressions than on flats and mounds, but these differences were not related to any major differences in forest floor pH, cellulose decomposition, total N and P, and available NH4+, NO3−, and phosphate P as measured using resin bags. The ecological significance of and possible reasons for the lack of correlation found between (i) western red cedar and fireweed growth and (ii) many measures of forest floor nutrient status are discussed.
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Tillman-Sutela, Eila, and Anneli Kauppi. "Structures restricting passage of water in the mature seeds of yellow-cedar (Chamaecyparis nootkatensis)." Canadian Journal of Botany 76, no. 8 (1998): 1458–66. http://dx.doi.org/10.1139/b98-135.
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Anatomical structures of seed surface layers and their role in impeding passage of water were studied for mature yellow-cedar (Chamaecyparis nootkatensis D. Don) seeds. The structures of the seed coat, nucellar layers, and megagametophyte of both dry and moistened, sectioned seeds were examined with a field emission scanning electron microscope. The anatomical details of resin-embedded seeds were studied by light or fluorescence microscopy using stained and unstained sections. The permeability of the structures exterior to the megagametophyte was analyzed by placing seeds in a Methylene Blue solution and examining them under a stereomicroscope. Results proved that the seed coat proper had only a minor effect on restricting passage of water. Penetration of staining solution was efficiently directed by the wing and epicuticular wax layer covering it, and by the large, impermeable nucellar cap. These structures, typical for yellow-cedar, essentially differed from those studied in Picea and Pinus seeds. Still, the most effective barrier to the penetration of water was in the junction formed by the megaspore membranes and the strong cuticle of the megagametophyte. These structures together with the phenolic nucellar tissues probably contribute to physiological dormancy in yellow-cedar seeds. Consequently, studies of the localization of dormancy should be focused on these layers rather than on the seed coat.Key words: conifer, seed coat, anatomy, scanning electron microscopy, imbibition.
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Ono, Kenta, Osamu Tanaike, Ryo Ishii, et al. "Solvent-Free Fabrication of an Elastomeric Epoxy Resin Using Glycol Lignin from Japanese Cedar." ACS Omega 4, no. 17 (2019): 17251–56. http://dx.doi.org/10.1021/acsomega.9b01884.
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Bhardwaj, Vibha. "Deodar Cedar (Cedrus Deodara): Efficacy for Potential of Secondary Metabolites and Antibacterial Activity." Biomedical Research and Clinical Reviews 6, no. 5 (2022): 01–09. http://dx.doi.org/10.31579/2692-9406/111.
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The setback of microbial resistance is growing and the use of antimicrobial drugs in the future is still uncertain. Infectious diseases are accountable for millions of global deaths annually. Therefore, necessary steps need to be taken to reduce this problem. In the present study, crude extracts of leaves, bark and resins of Cedrus deodara in methanol was investigated for secondary metabolites (flavonoids, glycosides, phenols, saponins, tannins, terpenoids) and antibacterial effect of Cedrus deodara was evaluated on multidrug resistant (MDR) strains of Bacillus subtilis (ATCC 6633), E. coli (ATCC 8739), Salmonella enterica (ATCC 14028), Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 27853) by agar well diffusion method. Ciprofloxacin was used as standard. The methanolic extracts of leaves of C. deodara tested positive for glycosides, flavonoids, phenol, tannins and terpenoids. The Bark was tested positive for glycosides, flavonoids, phenol, tannins but resins was tested positive for terpenoids. Leaves of C. deodara showed zone of inhibition with all the five strains of microorganisms, which were used. C. deodara resin methanolic extract showed maximum zone of inhibition with Bacillus subtilis which are 25 ± 0.1 mm and bark showed maximum zone of inhibition with Staphylococcus aureus 21 ± 0.6 mm. The potency shown by these extracts recommends their use against multidrug resistant microorganisms. Time-kill curve showed a fast and sharp antimicrobial activity. Based on the research experiments, it was identified, that the methanol extract of Cedrus deodara exhibited quite high antimicrobial activity as well as secondary metabolites and this quality together with lots of other values must be considered in green landscape planning of contemporary urban environment and for the other purposes too.
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Lee, Yun-Yun, Wen-Jau Lee, Ling-Ying Hsu, and Han-Min Hsieh. "Properties of molding plates made with various matrices impregnated with PF and liquefied wood-based PF resins." Holzforschung 68, no. 1 (2014): 37–43. http://dx.doi.org/10.1515/hf-2013-0029.
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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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KURIMOTO, Yasuji, Hidefumi YAMAUCHI, Takanobu SASAKI, and Satoru KANETAKA. "PRODUCTION AND APPLICATION OF WOOD-POLYURETHANE RESIN COMPOSITES USING STUBS AND ROOTS OF JAPANESE CEDAR." ENVIRONMENTAL SYSTEMS RESEARCH 34 (2006): 585–90. http://dx.doi.org/10.2208/proer.34.585.
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Jia, Chong, Yang Zhang, Juqing Cui, and Lu Gan. "The Antibacterial Properties and Safety of a Nanoparticle-Coated Parquet Floor." Coatings 9, no. 6 (2019): 403. http://dx.doi.org/10.3390/coatings9060403.
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Floor antibacterial technology prevents the human body from cross-infection with bacterial diseases. The most commonly used approach to endow daily-used floors with antibacterial properties is to apply a thin film of antibacterial agents on the parquet floor surface. In the present study, five commercial antibacterial nanoparticles were first dispersed in melamine resin solution, and then applied on a floor. Afterwards, the antibacterial properties of the nanoparticle-coated floor were investigated, in which Escherichia coli was used as the target bacteria. The impact of the nanoparticle dispersing agents on the ultimate antibacterial properties of the floor were also investigated. The results showed that silver nanoparticle-loaded hydroxyl zirconium sodium phosphate (Ag-HZDP) was most suitable as the antibacterial agent of a melamine coating for parquet flooring. With the help of sodium hexametaphosphate, the antibacterial agent was able to disperse well in the melamine resin solution and was also able to disperse well on the floor surface. When the loading amount of Ag-HZDP was 1 wt % or higher, the prepared antibacterial floor was able kill almost all the bacteria cultivated on its surface. Moreover, the prepared antibacterial floor had a lower toxicity compared with a pristine cedar substrate. The present study provides an effective way to provide daily-used parquet floors with excellent antibacterial properties.
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B, Purevsuren, Davaajav Ya, Batbileg S, et al. "Investigation on pyrolysis of some organic raw materials." Mongolian Journal of Chemistry 17, no. 43 (2017): 5–13. http://dx.doi.org/10.5564/mjc.v17i43.739.
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We have been working on pyrolysis of some organic raw materials including different rank coals, oil shale, wood waste, animal bone, cedar shell, polypropylene waste, milk casein and characterization of obtained hard residue, tar and pyrolytic water and gas after pyrolysis. The technical characteristics of these organic raw materials have been determined and the thermal stability characteristics such as thermal stability indices (T5% and T25%) determined by using thermogravimetric analysis. The pyrolysis experiments were performed at different heating temperatures and the yields of hard residue, tar, pyrolysis water and gaseous products were determined and discussed. The main technical characteristics of hard residue of organic raw materials after pyrolysis have been determined and the adsorption ability of pyrolysis hard residue and its activated carbon of organic raw materials also determined. The pyrolysis tars of organic raw materials were distilled in air condition and determined the yields of obtained light, middle and heavy fractions and bitumen like residue with different boiling temperature. This is the first time to investigate the curing ability of pyrolysis tars of organic raw materials for epoxy resin and the results of these experiments showed that only tar of milk casein has the highest (95.0%), tar of animal bone has certain (18.70%) and tars of all other organic raw materials have no curing ability for epoxy resin.
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Lyggitsou, Georgia, Christina Barda, Maria Anagnostou, et al. "Wound Healing Potential of Herbal Hydrogel Formulations of Cedrus brevifolia Extracts in Mice." Gels 10, no. 11 (2024): 750. http://dx.doi.org/10.3390/gels10110750.
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Wound healing stands as a paramount therapeutic pursuit, imposing significant challenges on healthcare, particularly for vulnerable populations. Cedrus brevifolia, a species endemic to Cyprus, thrives in the Tripylos region, commonly known as Cedar Valley, within the Paphos forest. Despite its endemism, this species exhibits negligible genetic divergence from its Mediterranean related species. This study aims to investigate the potential of C. brevifolia resin and bark extracts in promoting wound healing in a mouse model. Previous in vitro investigations have elucidated the antioxidant and anti-inflammatory potential of extracts and isolates derived from the title plant, warranting further exploration in an in vivo setting. This experimental design employed 40 male SKH-hr2 black and brown mice aged 2–4 months. Wounds measuring 1 cm2 were meticulously induced in the anesthetized mice and the potential healing effect of the herbal hydrogel formulations was evaluated. The healing potential of the C. brevifolia extracts was rigorously assessed through the daily application of gel formulations containing resin concentrations of 5% and 10% w/w, alongside sapwood and heartwood extracts at concentrations of 0.5% and 1% w/w. The evaluation of the treatments encompassed a multifaceted approach, incorporating clinical observations, skin biophysical parameter assessments utilizing an Antera 3D camera, and FT-IR spectroscopy, in addition to histopathological examination. The chemical compositions were also investigated through NMR and bio-guided isolation. The most prominent herbal hydrogel preparation proved to be the 10% resin, followed by the sapwood at 1%. The chemical analysis unveiled abietic acid, manool, and lariciresinol derivatives that potentially contributed to the observed results. Bridging the gap between in vitro observations and in vivo outcomes attempts to shed light on the potential therapeutic benefits of C. brevifolia hydrogels in wound care.
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SANUI, Takayoshi, and Junichi YUKAWA. "A New Gall Midge of the Genus Resseliella (Diptera : Cecidomyiidae) Inhabiting Resin of the Japanese Cedar, Cryptomeria japonica (Taxodiaceae)." Applied Entomology and Zoology 20, no. 1 (1985): 27–33. http://dx.doi.org/10.1303/aez.20.27.
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林伊涵, 林伊涵, та 林慶元 Yi-Han Lin. "國產材製成直交集成板之防火性能初探". 建築學報 118-1, № 118-1 (2021): 049–59. http://dx.doi.org/10.53106/101632122021120118010.
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<p>由於目前臺灣直交集成板（Cross-Laminated-Timber, CLT）大多為國外預製進口，若能直接運用國內生產木材，不旦可活絡國產材的市場，亦能輔助臺灣國產材製成CLT法規的推動。故本研究以國產材CLT進行耐火試驗初探，參考CNS12514-1「建築物構造部分之耐火試驗法」標準進行耐火試驗，以小尺寸45cm&times;45cm進行試驗，每次試驗為2至4片放入特製鐵框中以垂直(等同於牆)方向進行加熱，共加熱試驗6組總計20個試驗體。其中變數條件為三種國產材（柳杉Japanese cedar、臺灣杉Taiwania,及杉木China fir）、兩種膠合劑（間苯二酚樹脂膠合劑RF及乙烯脲酯膠合劑KR）及三種樹種強度（M30、M60及M90）分別進行30分鐘與60分鐘之耐火試驗。綜合變數條件及試體炭化深度比較，結果如下：1.柳杉為三種樹種中炭化深度最少之樹種。2.強度M30、M60及M90之平均炭化速率分別為0.67 mm/min、0.72 mm/min及0.79 mm/min，本實驗結果為等級越高有提高炭化速率的趨勢。3.膠合劑不同炭化深度較無差別，但膠合效果以間苯二酚樹脂為佳。</p> <p>&nbsp;</p><p>At present, cross-laminated-timber (CLT) buildings in Taiwan are prefabricated and imported from overseas. If wood materials made from domestic timber in Taiwan can be directly used, encouraging the market for domestic timber and assisting in the promotion of regulations for CLT made from domestic timber. This study is a preliminary discussion on fire resistance performance in accordance with the CNS12514-1 standard of CLT made from domestic timber. The experiments were conducted with a small timber size of 45cm&times;45cm. There were 20 test specimens carrying out the fire resistance test for respective 30 and 60 minutes. The variation of conditions included three domestic timber species (Japanese cedar, Taiwania, China fir), two types of adhesives (Resorcinol formaldehyde resin, Vinyl urethane adhesive) and three tree species strengths (M30, M60, M90). There were six times of fire resistance tests, with 2 to 4 pieces heated up in a special iron frame in each.In conclusion, comparison of the several variation conditions and the char depths of the test specimens, yielded the following results:1. Japanese cedar is the least char depths in the three domestic timber species. 2. In this study, the higher the level, the faster the charing rate.3. The best adhesive is resorcinol formaldehyde resin.</p> <p>&nbsp;</p>
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Chien, Tsai-Po, Te-Hsin Yang, and Feng-Cheng Chang. "Flexural Performance of Built-Up Beams Made with Plantation Wood." Forests 10, no. 8 (2019): 647. http://dx.doi.org/10.3390/f10080647.
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In this study, Japanese cedar (Cryptomeria japonica (L. f.) D. Don) harvested from a plantation in Taiwan was used to develop built-up beams using self-tapping screws as metal connectors and resorcinol formaldehyde resin as glue to assemble components based on various assembly configurations. Results showed that adding glue provided flexural rigidity, whereas assembly using self-tapping screws resulted in built-up beams with high ductility but relatively low flexural bearing capacity. Beams used glue exhibited approximately linear behavior, whereas those using only screws exhibited some undulating and stepwise responses, implying that shear force between the flanges and the web may cause buckling as well as the dislocation of the self-tapping screws. When using components of similar grades, adding another web can improve the performance. Furthermore, the grades of flanges can strongly influence the flexural load-bearing capacity. In addition, a smaller spacing between the screws can improve the flexural load-bearing performance, but also cause wooden components to crack. Typical bending failure modes were observed in the developed built-up beams, indicating tension failure of the bottom flange as well as slippage between flanges and the web due to horizontal shear, which also caused buckling deformations in the screws.
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Sharonova, N. L., D. A. Terenzhev, A. P. Lyubina, I. D. Fadeeva, and A. T. Zakirov. "Substances for biological protection, regulation of growth and development of agricultural crops based on secondary plant metabolites." IOP Conference Series: Earth and Environmental Science 949, no. 1 (2022): 012049. http://dx.doi.org/10.1088/1755-1315/949/1/012049.
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Abstract Plants are a promising source of a wide range of biologically active substances as biopesticides and growth stimulants in organic agriculture. Screening of the antimicrobial activity of ethanol extracts of air-dry aboveground biomass of 22 plant species of the family Asteraceae, typical representatives of the flora of the Republic of Tatarstan, was carried out. The antibacterial activity of greater knapweed (Centaurea scabiosa L.), milk thistle (Silybum marianum (L.) Gaertn), scentless mayweed (Tripleurospermum inodorum (L.) Sch. Bip.), marsh cudweed (Gnaphalium uliginosum L.) against test strains of microorganisms – Clavibacter michiganensis VKM Ac-1404 (phytopathogenic gram-positive bacterium) and Alternaria solani St108 (phytopathogenic fungi) was established. The highest indices of inhibitory activity were found in the case of marsh cudweed - 0.0063%. The efficiency of pre-sowing treatment of seeds and foliar treatment of plants with an aqueous solution the potassium salts of terpene acids of Siberian cedar pine resin on the yield of winter wheat variety Kazanskaya-560 on gray forest soil at the Republic of Tatarstan was revealed. The yield increase was 3.7-3.9% to control. The grain size indicator (1000 grains weight) varied in the range of 36-38 g with the highest values in the case of pre-sowing treatment.
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Khan, Muhammad Usman, Muhammad Abas, Sahar Noor, Bashir Salah, Waqas Saleem, and Razaullah Khan. "Experimental and Statistical Analysis of Saw Mill Wood Waste Composite Properties for Practical Applications." Polymers 13, no. 22 (2021): 4038. http://dx.doi.org/10.3390/polym13224038.
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The utilization of composite materials is increasing at a growing rate in almost all types of products, due to their strength-to-stiffness ratio. From this perspective, natural waste composites, i.e., wood waste composites, have also been investigated for their effective and sustainable employment. This paper deals with the application of hard and soft wood waste (i.e., acacia and cedar wood) with epoxy resin polymer to develop high strength and thermally stable wood composites. Mechanical (tensile, flexural, impact, and hardness) and thermal properties of samples are studied using Differential Scanning Calorimeter (DSC) and Thermo Gravimetric Analysis (TGA), respectively. The properties are evaluated by varying the type of wood waste and its percentage by weight. Based on the Taguchi Orthogonal Array Mixture Design, eighteen experiments are investigated. Analysis of variance (ANOVA) results show that wood waste type and wood waste content have a significant effect on all mechanical properties. From the TGA analysis, it is predicted that both types of wood waste composites exhibit similar thermal-induced degradation profiles in terms of the initial and final degradation temperatures. From the DSC results, higher glass transition temperature Tg is detected in 10% of the hardwood waste composite, and a reducing tendency of glass transition temperature Tg is observed with exceeding wood waste content. Moreover, hardwood waste at 10% demonstrated improved decomposition temperature Td, due to strong adhesion between waste and matrix.
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Ito, Kensuke. "Spatial extent of traumatic resin duct induction in Japanese cedar, Cryptomeria japonica D. Don, following feeding damage by the cryptomeria bark borer, Semanotus japonicus Lacordaire (Coleoptera : Cerambycidae)." Applied Entomology and Zoology 33, no. 4 (1998): 561–66. http://dx.doi.org/10.1303/aez.33.561.
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Chang, Chia-Wei, Wei-Ling Kuo, and Kun-Tsung Lu. "On the Effect of Heat Treatments on the Adhesion, Finishing and Decay Resistance of Japanese cedar (Cryptomeria japonica D. Don) and Formosa acacia (Acacia confuse Merr.(Leguminosae))." Forests 10, no. 7 (2019): 586. http://dx.doi.org/10.3390/f10070586.
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In Taiwan, it is important to maintain sustainable development of the forestry industry in order to raise the self-sufficiency of domestic timber. Japanese cedar (Cryptomeria D. Don and Formosa acacia (Acacia confusa Merr.(Leguminosae)) have abundant storage options and are the potential candidates for this purpose. Heat treatment is a new environment-friendly method used to enhance the dimensional stability and durability of wood. On treatment, a surface with new characteristics is produced because of wood component changes. Consequently, an inactivated surface and a weak boundary layer are generated, and the wettability for adhesives and coatings is reduced. Furthermore, it decreases the pH value of the wood surface, and results in delay or acceleration during the curing of adhesives. This phenomenon must be paid attention to for practical applications of heat-treated wood. Ideal heat-treated conditions of C. japonica and A. confusa woods with productive parameters such as temperature, holding time, heating rate, and thicknesses of wood were identified in our previous study. In this research work, we focus on the normal shear strength of heat-treated wood with adhesives such as urea-formaldehyde resin (UF) and polyvinyl acetate (PVAc), and the finishing performances of heat-treated wood with polyurethane (PU) and nitrocellulose lacquer (NC) coatings as well as assessing the decay-resistance of heat-treated wood. The results show that heat-treated wood had a better decay resistance than untreated wood. The mass decrease of heat-treated wood was only 1/3 or even less than the untreated wood. The normal shear strength of heat-treated wood with UF and PVAc decreased from 99% to 72% compared to the untreated wood, but the wood failure of heat-treated wood was higher than that of the untreated one. Furthermore, the adhesion and impact resistance of wood finished by PU and NC coatings showed no difference between the heat-treated wood and untreated wood. The finished heat-treated wood had a superior durability and better gloss retention and lightfastness than that of the untreated wood.
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VALEEV, F. A. "SYNTHESIS OF ELEUTHESIDES." Izvestia Ufimskogo Nauchnogo Tsentra RAN, no. 2 (June 10, 2024): 8–25. http://dx.doi.org/10.31040/2222-8349-2024-0-2-8-25.
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The review is devoted to research in the field of "marine" diterpene metabolites of the 4,7-oxaeunicellan type, which have a taxol-like mechanism of cytotoxic action. The known most effective chemical syntheses are presented, as well as the results of our own research, on the basis of which, based on (+)-δ-cadinol, the formal synthesis of eleuthesides was realized, and the synthesis of analogs of sorcrdictyin A and eleutherobin was carried out from the Diels-Alder adduct of levogluclsenone and piperylene. In the course of the research, the features of the chemical behavior of the little-studied sesquiterpene (+)-δ-cadinol, isolated from the resin of the Siberian cedar Pinus sibirica R.Mayer, were revealed, which caused certain difficulties at the initial stage of research when developing a scheme for the synthesis of eleuthesides. Thus, the ozonolytic cleavage of the double bond, regardless of the reaction conditions, was accompanied by α-ketol rearrangement and aldol cyclization. Both problems were solved by protecting the aldehyde group into dimethyl acetal, and the hydroxyl groups by intramolecular oxacyclization into 1,4-epoxide. After the construction of the "upper" and "lower" side chains, the reverse transition from the 1,4-epoxide to the linear structure was carried out by the action of BF3·Et2O-Ac2O to obtain a diacetate derivative corresponding to the key synthon of the synthesis scheme of Nicolau et al., which completed the formal synthesis of eleuthesides. Based on the analysis of literature data on the properties of N-methylurocanoic acid and its role in sarcodictyins, an assumption was made about the manifestation of cytotoxic properties by more accessible esters of the little-studied N-methylurocanoic acid. In this regard, methods have been developed for obtaining esters of urocanic acid from histidine and glucose and its N-methylation. Then, esters of N-methylurocanoic acid were synthesized with a number of alcohols, including those of natural origin. Using a similar strategy, a scheme was developed for the synthesis of the structural core of an eleutheside analog with a 14-methylcyclohexene ring A starting from the Diels-Alder adduct of levoglucosenone and piperylene. The key step of the scheme is the intramolecular acetylenealdehyde cyclization into a 10-membered carbocycle, which completes the construction of the eleutheside core. Trichloroacetimidate, a glycosylation agent in the synthesis of eleutherobin, was obtained. Synthetic studies have been completed by obtaining analogs of sarcodictin A with a 14-methylcyclohexene ring A and an analog of eleutherobin with a similar ring A and an orthoester arabinose substituent.
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Sahin, H. T. "Application of various solvent‐type alkyd resins to pine and cedar woods for achieving water repellence." Pigment & Resin Technology 37, no. 6 (2008): 395–401. http://dx.doi.org/10.1108/03699420810915094.
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Grosser, Dietger. "On the Occurrence of Trabeculae With Special Consideration of Diseased Trees." IAWA Journal 7, no. 4 (1986): 319–41. http://dx.doi.org/10.1163/22941932-90001003.
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Comprehensive investigations on trabeculae in softwoods have shown that they occur much more frequently than has hitherto generally been assumed. A systematic study oflarge series of microtome sections, i.e., transverse sections and particularly radial sections of extended annual ring sequences will, as a rule, give sufficient evidence for the occurrence of trabeculae and related structures. Apart from this phenomenon an increased occurrence of trabeculae was often found in the annual rings of healthy and diseased trees from forest decline areas from the middle of the 1970's onwards. Moreover, trabeculae occur with particularly great frequency and in significantly larger numbers than in nonnal wood in association with wound tissue fonnation as a consequence of injuries, in spruce with hazel growth, or in cedars with traumatic resin ducts. Also, in compression wood trabeculae are fonned much more often than in normal wood. A detailed survey of trabeculae structure and possible patterns of trabeculae arrangement is also given.
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Ogawa, Keita, Satoshi Fukuta, and Kenji Kobayashi. "Embedment properties of Japanese cedar (Cryptomeria japonica) treated with resin impregnation." Journal of Wood Science 68, no. 1 (2022). http://dx.doi.org/10.1186/s10086-022-02018-5.
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AbstractTo strengthen the embedment properties of wood, this study applied the resin impregnation technique, which fills the resin into wood cells. The urethane prepolymer and acrylic monomer were selected in this study. A mechanical test by a round steel bar loaded to the wood specimen was conducted. The characteristics showed higher values in the resin-impregnated groups than in the control specimen group, especially in the stiffness. The urethane- and acryl-impregnated group showed 3.78 and 2.27 times the stiffness values of the control groups in the parallel-loaded condition, and 1.94 and 1.24 times those of the control group in the perpendicularly loaded condition, respectively. Although the stiffness was significantly increased, there was a lack of ductility, which seems to be a serious problem for construction application.
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Filippov, Dionis, Andrey Blinov, Alexey Gvozdenko, et al. "Hydrophobization of Silicon Dioxide Microspheres With Resin Acids of Natural Gums." Polymers for Advanced Technologies 36, no. 2 (2025). https://doi.org/10.1002/pat.70114.
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ABSTRACTCurrently, hydrophobic materials and coatings are of great practical interest due to their unique functional characteristics. The aim of this study was to develop a hydrophobic agent based on SiO2 microspheres hydrophobized with resin acids of natural gums to protect various surfaces. According to quantum chemical modeling, the most energetically advantageous interactions are those of SiO2 with birch gum and pine gum through the COO− group of dihydroabietinic acid (E = −1361.256 kcal/mol), and with cedar gum through COO− group of lambertianic acid (E = −1433.537 kcal/mol). Notably, the most stable “SiO2 – resin acid” molecular complex (η = 0.140 eV) forms when the Si atom interacts with COO− group of dehydroabietinic acid. The synthesized samples are represented by irregularly shaped aggregates consisting of spherical SiO2 microspheres. Two fractions of microspheres with sizes of 50–150 and 400–1000 nm are observed in all the obtained samples. FTIR spectra prove that interaction of SiO2 with resin acids occurs through COO− groups. Samples containing 0.01% and 1% of pine gum as well as all samples containing from 0.05% to 1% of cedar gum have expressed hydrophobic properties, while samples with birch gum, in contrast, have hydrophylic properties.
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Wang, Xin, Bin Li, Dongyan Liu, et al. "Isolation, characterization, and LC MS/MS determination of anti-obesity components from pine needles of Cedrus deodara (Roxb.) G. Don." Frontiers in Nutrition 11 (August 1, 2024). http://dx.doi.org/10.3389/fnut.2024.1448908.
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ObjectiveThis study aimed to isolate and analyze the components in cedar pine needles (needle leaves of Cedrus deodara (Roxb.) G. Don) that exhibit anti-obesity effects, as determined through animal experiments.MethodsThe extract of cedar pine needles was separated into four fractions of different polarities using a macroporous resin column. The fraction that retained anti-obesity activity was evaluated based on the results of animal experiments. Monomeric compounds were structurally characterized and isolated from the active fraction using a preparative liquid chromatography system. Combined with subsequent glucose gel chromatographic separation. The content of the separated components was determined using ultrahigh performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-QQQ-MS/MS).ResultsThe water-washed fraction retained anti-obesity activity of the cedar pine needles more effectively. A total of 16 compounds were separated from this fraction, and the contents of 14 of these compounds were determined to be present in cedar pine needles.ConclusionNine components, namely p-hydroxy benzyl alcohol, chlorogenic acid, vanillic acid, syringic acid, P-coumaric acid, sinapic acid, benzoic acid, phenylacetic acid, salicylic acid, were characterized and determined for the first time in cedar pine needles. The components with anti-obesity activity in the pine needles of Cedrus are mainly derived from phenolic acids.
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Sun, Minkai, Taisuke Nakashima, Yuri Yoshimura, et al. "Effects and interaction of different interior material treatment and personal preference on psychological and physiological responses in living environment." Journal of Wood Science 66, no. 1 (2020). http://dx.doi.org/10.1186/s10086-020-01910-2.
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Abstract Japanese cedar (Cryptomeria japonica) wood is widely used as a traditional construction material in Japan. The relationship between an individual’s perceived comfort level and a preference for Japanese cedar wood interiors is of interest. We compared volunteers’ physiological responses and subjective evaluations of wooden dwelling spaces with different wood materials: planed Japanese cedar lumber, or printed grain resin sheet overlay boards. Eighty-three subjects were asked to stay in each room for 30 min. We evaluated salivary stress markers, blood pressure, the profile of mood states-brief form (POMS), and a questionnaire that used the semantic differential method to evaluate the subjects’ feeling state for both rooms. The concentrations of the volatile organic compounds in both rooms were also quantified after the experiment. The results demonstrated that the subjects’ evaluation of each room was highly dependent on their preference; each room was evaluated more positively by subjects who preferred it. Although the subjects’ feelings were also influenced by their preference, the room with Japanese cedar did not elicit negative feelings, even from the subjects who disliked it. The subjects’ physiological responses were totally independent of their preferences. Their blood pressure decreased in the Japanese cedar room, and their salivary alpha-amylase activity was repressed in both rooms. These results indicated that the subjective evaluations were influenced in part by the subjects’ preferences, while their physiological responses were not affected. Regardless of which room the subjects preferred, the Japanese cedar room reduced the subjects’ blood pressure compared to the room with artificial materials.
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Ogawa, Keita, Kenji Kobayashi, and Satoshi Fukuta. "Compression properties of Japanese cedar (Cryptomeria japonica) treated with resin impregnation under loading perpendicular to the grain." Journal of Wood Science 70, no. 1 (2024). http://dx.doi.org/10.1186/s10086-024-02142-4.
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AbstractThe compression properties of wood perpendicular to the grain is an important resistance mechanism in timber joints, especially wood-to-wood joints. Hence, improving the compression properties of wood is essential to developing timber joints with high resistance performance. In this study, we attempted to improve the compression properties using a resin impregnation technique. Three compression tests were conducted: loading at the full surface of the specimen, loading at the local part of the specimen with the unloaded part expanding in the tangential direction, and loading at the local part of the specimen with the unloaded part expanding in the longitudinal direction. Two types of resins were used: urethane and acryl. For compression loading on the full surface, the stiffness was increased by resin impregnation in the case of acryl impregnation. However, the yield load did not increase significantly. In the cases of compression loading in the local part and unloaded part expanding in the tangential direction, the stiffness increased when acryl was used, and the yield load increased when both resins were used. Significant increment in the properties were observed when the local compression load acted on the specimens with the unloaded parts expanding in the longitudinal direction. When urethane and a 10 mm incision depth were used, the stiffness and yield load increased 1.35 and 2.54 times, respectively. When using acryl and a 10 mm incision depth, the stiffness and yield load increased 1.64 and 2.93 times, respectively.
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Lee, Wen-Jau, Chen-Ling Kang, Kuo-Chun Chang, and Yi-Chun Chen. "Synthesis and properties of resol-type phenol-formaldehyde resins prepared from H2SO4- and HCl-catalyzed phenol-liquefied Cryptomeria japonica wood." Holzforschung 66, no. 1 (2012). http://dx.doi.org/10.1515/hf.2011.121.
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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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Kosugi, Shun, Marina Totsuka, Hiroki Nakashima, Masakazu Ikeda, and Kenji Aoki. "Compressive behavior of wood contact with mortar and epoxy resin adhesives." European Journal of Wood and Wood Products 83, no. 3 (2025). https://doi.org/10.1007/s00107-025-02221-3.
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Abstract In recent years, researchers and engineers have developed a wide range of connection systems between wood and other materials, such as concrete and steel. However, the mechanical behavior of the surfaces where wood meets these materials is yet to be understood. In wood, low-stiffness areas called damage zones form near end grains, when compressed parallel to the grain. These low-stiffness areas may come in contact with various materials; therefore, understanding the behavior of the damage zones with various materials is important. This paper describes the results and analysis of experimental tests conducted on 130 specimens compressed parallel to the grain, to examine the compression behavior when the low-stiffness areas of glulam (Japanese cedar and Japanese larch) come in contact with mortar, epoxy adhesives, and steel. Compared with specimens joined with steels, the specimens joined with mortar had lower strength and stiffness, whereas those with epoxy structural adhesives had higher or almost equivalent strength and stiffness. Additionally, the specimens joined with mortar had the most significant strain in the damage zone, followed by those with steel loading plates and those with epoxy structural adhesives. These results suggest that using mortar as a contact material has a detrimental effect on the strength and stiffness of glulam. In contrast, the use of epoxy structural adhesives can improve the stiffness of glulam by mitigating the effects of the damage zone.
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Ogawa, Keita, Satoshi Fukuta, and Kenji Kobayashi. "Experimental study of lateral resistance of bolted joints using Japanese cedar (Cryptomeria japonica) treated with resin impregnation." Journal of Wood Science 66, no. 1 (2020). http://dx.doi.org/10.1186/s10086-020-01918-8.
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Abstract The development of wooden joints possessing high resistance performance has become an important issue for the construction of newer buildings. This study attempts to strengthen the lateral resistance of bolted joints using the previously reported plasticizing technique. This technique consists of two processing stages: incising the surface of the wood using an ultraviolet wavelength short-pulse laser and impregnating the resin into the incised area. This technique makes it possible to plasticize only a local part of the wood surface. Bolted joint specimens were assembled using plasticized wood around the bolt hole, and the lateral tests were conducted. Acrylic monomer and urethane prepolymer were used as the impregnating resins and their incision depths were set as 4 and 10 mm. When the lateral load acted parallel to the grain, changes in the lateral resistance characteristics were observed, especially for the stiffness and yield load. For example, when acryl was used, and the incision depth was 10 mm, an increment of 73% in the yield load was observed, as compared to the non-impregnated specimens. The specimen groups impregnated with acryl exhibited greater changes in their properties than those using urethane. When loaded perpendicular to the grain, an increase in properties were observed; however, these increments were lower than those of the groups loaded parallel to the grain.
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Okamoto, Tsuyoshi, Taisuke Nakashima, Kurniawan Eka Permana, et al. "Electrophysiological effects of Japanese cedarwood on sleep quality in humans." Journal of Wood Science 70, no. 1 (2024). http://dx.doi.org/10.1186/s10086-024-02150-4.
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AbstractSleep plays an important role in human health. Changes in the sleeping environment can affect sleep quality. The present study investigated the effects of natural wood on sleep quality. The interior material was a fully used Cryptomeria japonica wood board (Japanese cedar room), while the particleboard and medium-density fiberboard (MDF) were covered by a vinyl cloth with a woodgrain (resin room). In order to assess sleep quality, the sleep–depth index (SDI) is calculated based on the lengths of sleep stage 3 and the rapid eye movement (REM) stage using electroencephalography (EEG). Before the sleep experiments, the Pittsburgh Sleep Quality Inventory (PSQI) and Morningness–Eveningness Questionnaire (MEQ) were administered to confirm the participants’ usual sleep habits. Thirteen participants were invited to sleep in two different environments. The MEQ before sleep experiments confirmed that eight participants were of the intermediate type and five participants were of the moderate evening type. According to the PSQI, three participants were poor sleepers and ten were good sleepers. The sleep EEG demonstrated that 12 of 13 participants had higher SDI in the Japanese cedarwood room than in the resin room. A Wilcoxon signed-rank test revealed that SDI was significantly prolonged in the Japanese cedarwood room than in the resin room, regardless of the small sample size (n = 13, z = 2.48, p = 0.014, effect size = 0.78). The present study demonstrated that the indoor environment with C. japonica induced a significantly higher SDI compared to that with wood-grain vinyl cloth. This indicates that the interior materials of C. Japonica wood can positively influence the sleep environment.
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Sahin, Halil Turgut, and Ismail Erbil. "A Study on Surface Physicochemical Properties of Woods Treated in Emulsion of Waterborne Varnish with Sesame and Grape Seed Oil." Asian Journal of Biotechnology and Bioresource Technology, March 27, 2021, 1–9. http://dx.doi.org/10.9734/ajb2t/2021/v7i130090.
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Aims: An eco-friendly coating emulsion prepared with mixture of oils of sesame and grape seed and alkyd-based waterborne varnish. The prepared emulsion applied four different wood substrates (walnut, beech, cedar and fir) in order to be investigated for some selected surface properties.
 Study Design: Several test methods were used to evaluate surface physicochemical properties of the coatings. The results obtained may be suggested for the selection of the best varnish-emulsion formulation for the improvement wood substrates and could provide useful evaluation of the test methods employed.
 Methodology: The wood species of Beech (Fagus sylvatica), Walnut (Juglans regia), Cedar (Cedrus libani) and Fir (Abies nordmandiana) were selected for the investigation. Commercially available alkyd based waterborne varnish was supplied ready to use form.
 Both sesame oil (Sesamum indicum L.) and grape seed oil (Vitis vinifera L.) were obtained from a company that produces them by the cold press technique commercially. Both oils were used as supplied, without additional processing. These oils were added to varnish at 10% and 20% proportions (volume/volume). The 5 μl of distilled water (surface tension of 72.6 mN /m) was applied on wood surface by a sessile droplet method to measure surface contact angles. The surface hardness and scratch resistance of the cured varnish layers on wood substrates were measured with using pencil hardness test procedure according to ASTM-D-3363 standard. Cross cut test also conducted according to EN ISO 2409 standard.
 Experimental Findings: It was found that coated walnut samples show 9.8 to 13.5° higher contact angle values in all directions while other three wood samples only show marginally different values (0.1 to 4.3°). The highest contact value of 35.9° and 35.8° was found with samples of Wg20 and Wg10 which treated 20- and 10% grape seed oil proportions in varnish emulsion. The oils of sesame and grape seed typically contain various proportions of fatty acids fractions which are constituents of a carboxylic acid with a long, aliphatic tail. These groups could be created a strong bond in combination with alkyd resin on wood surface. However, the surface energy distribution show only marginally changes regardless of treatment levels and conditions. Therefore, there is not any clear advantage observed on surface wood surface energy levels with coating applications. For 10% grape seed oil/varnish emulsion conditions, the hardness of coated surfaces found to be 3H, 3H, 2H, 2H for walnut, beech, fir and cedar, respectively. At 20% grape seed oil/varnish coatings, all coating surfaces show H level range. For cross hatch experiments, marginally similar trend was observed with 10-and 20% grape seed oil/varnish and 10% sesame oil/varnish emulsion coated wood species. Moreover, it was ranked 2 for fir, ranked 3 for beech and ranked 4 for cedar wood at 20% sesame oil/varnish emulsion coatings. It is noticeable that a correlation was observed between cross cut and surface scratch resistance properties with coated surfaces.
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Schimanofsky, Corina, Andreas Petritz, Boyuan Ban, et al. "Natural Dielectrics for Organic Field Effect Transistors: A Study of Resins from Larch, Spruce and Atlas Cedar Pinaceae Trees." Materials Advances, 2025. https://doi.org/10.1039/d5ma00401b.
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Three pinaceae resins originating from trees of high industrial significance: European larch, European spruce, and Atlas cedar that were examined in this work exhibit exceptional film formation, great dielectric qualities,...
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Henley, Brandon Christian, Maureen Okafor, Ambar Kulshreshtha, Antoine Trammell, and Ihab Hajjar. "Effects of candesartan on cerebral microvascular function in mild cognitive impairment: Results of two clinical trials." International Journal of Stroke, January 16, 2023, 174749302311533. http://dx.doi.org/10.1177/17474930231153313.
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Background: Cerebral microvascular dysfunction is commonly seen in Alzheimer’s disease (AD) and vascular cognitive impairment (VCI). Cerebrovascular reactivity (CVR) to CO2 reflects cerebral microvascular health and may be modulated by the renin-angiotensin system (RAS). This study aimed to investigate the effects of RAS modulation on CVR in individuals with mild cognitive impairment (MCI) due to underlying vascular or AD etiologies. Methods: This study presents findings of candesartan’s effects on the secondary outcomes of two double-blind randomized clinical trials of 12-month therapy of candesartan vs. lisinopril in VCI (CALIBREX) and candesartan vs. placebo in prodromal AD (CEDAR). Primary outcome results of these trials have been reported in previous publications. Participants underwent identical brain BOLD-CVR in response to a 2-minute CO2 challenge at baseline and 12 months. Regions of interest and voxel-wise CVR maps were derived from BOLD signal changes during CO2 challenge. CVR effects were compared between candesartan and lisinopril (CALIBREX) and candesartan and placebo (CEDAR) using mixed model repeated measures. Results: Data from 102 participants in the CALIBREX study (mean age 65 yrs, 45% female, 63% African American) and 59 in the CEDAR study (mean age 67 yrs, 32% female, 20% African American) were analyzed. Candesartan was associated with improved whole brain CVR compared to placebo in the CEDAR study (adjusted within-group mean difference for candesartan: 0.27 (95% CI: 0.006, 0.53) vs. placebo: −0.17 (95% CI: 0.42, 0.08), p-value=0.018), and compared to lisinopril in the CALIBREX study (adjusted within group mean difference for candesartan 0.28 (95% CI: 0.10, 0.46) vs. lisinopril −0.08 (95% CI: −0.31, 0.14), p-value=0.012), independent of blood pressure. In an exploratory meta-analysis of the two trials, improved CVR in the hippocampus was linked to improved attention and working memory (p=0.044) and a trend for improved executive function (p=0.087) with candesartan therapy. Conclusions: This study suggests that candesartan is associated with improved microvascular function in mild cognitive impairment, and these findings are independent of its blood pressure effect in these VCI and prodromal AD populations.