Condensation reactions of phenolic resins III: self-condensations of 2,4-dihydroxymethylphenol and 2,4,6-trihydroxymethylphenol (1)     

Naruyuki Kamo  Mitsuo Higuchi  Takehiro Yoshimatsu  Yukiko Ohara  Mitsuhiro Morita 《Journal of Wood Science》2002,48(6):491-496

This study reexamined the kinetics of the condensation reactions of hydroxymethylphenols with the purpose of elucidating the reaction mechanisms. This report discusses experimental results on the self-condensations of 2,4-dihydroxymethylphenols (2,4-DHMP) and 2,4,6-trihydroxymethylphenol (THMP), focusing on the order of reaction. The relations between the initial rates of reaction and the initial concentrations of reactants were investigated. Results quite different from those of previous reports were obtained. The order of reaction of the selfcondensation of 2,4-DHMP was found to be 1.1, which did not change with the alkali/2,4-DHMP molar ratio. The order of reaction of the self-condensation of THMP was found to vary with both the concentration of THMP and the alkali/THMP molar ratio. In the region of THMP concentrations above 1.5mol/l, the order of reaction was confirmed to be 2.0, which did not change with the alkali/THMP molar ratio. In the region of THMP concentrations below 1.0mol/l, the order of reaction varied with the alkali/THMP molar ratio, showing fractional numbers of 1.2–1.6. These results indicate that unimolecular reaction(s) and bimolecular reaction(s) take place simultaneously as the ratedetermining step in the condensation reactions of 2,4-DHMP and THMP and that the reaction mechanism changes with the species of reactant and, in some cases, with the reaction conditions.Part of this study was presented at the Wood Adhesives 2000 symposium, South Lake Tahoe, Nevada, USA, June 2000  相似文献   

Termiticidal activity of wood vinegar, its components and their homologues   总被引：5，自引：0，他引：5  

Mitsuyoshi Yatagai  Madoka Nishimoto  Keko Hori  Tatsuro Ohira  Akira Shibata 《Journal of Wood Science》2002,48(4):338-342

The termiticidal activity of wood vinegar, its components, and their homologues have been studied. Three kinds of wood vinegar made from the mixed chips ofCryptomeria japonlca andPseudotsga menziesii (wood vinegar A),Quercus serrata (wood vinegar B), andPinus densiflora (wood vinegar C) exhibited high termiticidal activities againstReticulitermes speratus. Acetic acid, which is the largest content of wood vinegar, exhibited high termiticidal acitivity. The contents of organic fraction of wood vinegars and acetic acid might be responsible for the differences in termiticidal activities among these wood vinegars. The structure and termiticidal activity relations of phenols were studied. Phenol with some substituents revealed higher termiticidal activity than benzene derivatives, which have no hydroxyl group; an ortho substituent of phenol plays an important role in termiticidal activity. It has become apparent that high termiticidal activity cannot be obtained by a phenolic hydroxyl group alone; it can be obtained, however, by some substituents, especially an ortho substituent in addition to a phenolic hydroxyl group. The bulkiness of the substituent at the ortho position participates in termiticidal activity; activity decreases as the size of an ortho substituent increases. It is thought that the interaction at the receptor site of termites is affected by the increased size of the ortho substituent.  相似文献   

Structural characteristics of cell walls of kenaf (<Emphasis Type="Italic">Hibiscus cannabinus </Emphasis>L.) and fixation of carbon dioxide     

Thi Bach Tuyet Lam  Keko Hori  Kenji Iiyama 《Journal of Wood Science》2003,49(3):255-261

 Kenaf (Hibiscus cannabinus) plants are widely known for their contribution to the global and regional environment because of their ability to fix CO₂. On the other hand, some scientists have doubts about CO₂ fixation by kenaf and have misgivings about the effect of kenaf on the ecosystem. We have characterized the structural characteristics of cell walls of bast fibers, cores, roots, and leaves of kenaf during the maturation of plants and investigated the rate of photosynthesis. During maturation of the kenaf plant the cellulose (bast fiber 52–59%, core 44–46%) and lignin (bast fiber 9.3–13.2%, core 18.3–23.2%) contents increased significantly. The aromatic composition of the lignin of bast fiber was significantly different from that of the core lignin and of other plants. The lignin of bast fiber appears similar to pure syringyl lignin. Fixation of CO₂ by kenaf plants and their contribution to the global environment are discussed. A significatly high rate of photosynthesis of kenaf plants was observed compared to that of woody plants in Japan, but the amount of CO₂ fixation depends on the characteristics of the plantation. If the kenaf was planted in high density, about twice as much CO₂ was fixed as was fixed by trees in a tropical rain forest. Received: April 22, 2002 / Accepted: July 24, 2002 Acknowledgments This project was supported by the Science and Technology Agency (STA) fellowship of the Japan International Science and Technology Exchange Center (JISTEC), which has been successfully applied by Dr. Shuji Hosoya, Forestry and Forest Products Research Institute. We thank Dr. Toshio Sumizono and Mr. Masao Sakurai, Forestry and Forest Products Research Institute, for their kind help in determining the rate of photosynthesis and cultivating the kenaf plants, respectively. We also express our appreciation to Dr. Quang Hung Le, College of Agriculture and Forestry, Ho Chi Minh City, Vietnam for offering information about the cultivation of kenaf at Thu Duc District, Ho Chi Minh City.  相似文献   

Quantitative PCR detection of feline morbillivirus in cat urine samples     

Tetsuya FURUYA  Akiko WACHI  Yukiko SASSA  Tsutomu OMATSU  Makoto NAGAI  Ryuji FUKUSHIMA  Makoto SHIBUTANI  Tomohiro YAMAGUCHI  Yosuke UEMATSU  Kinji SHIROTA  Tetsuya MIZUTANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1701-1703

  相似文献   

Accessory corpora lutea formation in pregnant Hokkaido sika deer (Cervus nippon yesoensis) investigated by examination of ovarian dynamics and steroid hormone concentrations     

Yojiro YANAGAWA  Yukiko MATSUURA  Masatsugu SUZUKI  Shin-ichi SAGA  Hideto OKUYAMA  Daisuke FUKUI  Gen BANDO  Masashi NAGANO  Seiji KATAGIRI  Yoshiyuki TAKAHASHI  Toshio TSUBOTA 《The Journal of reproduction and development》2015,61(1):61-66

Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17β and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17β, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17β after copulation.  相似文献   

Effect of lactoferrin on murine embryo development created from lipopolysaccharide-treated sperm     

Takahiro AYA  Yukiko TOMIOKA  Takashi TAKEUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1144

The effect of lactoferrin (LF) on embryo development was investigated by using lipopolysaccharide (LPS)-treated mouse sperm. For the development rate of the 2-cell stage embryo, the embryo derived from LPS- and LF-treated sperm showed similar survival rate to the control embryo. On day 12 after the embryo transfer into the recipient, the frequent abnormality was observed in the embryo derived from LPS-treated sperm, and the abnormality was tended to be inhibited in the embryo derived from LPS- and LF-treated sperm. These results imply that LF treatment on sperm contaminated with bacteria may facilitate the embryo development, which contribute to the improvement of infertility.  相似文献   

Contamination of Poultry Products with Listeria monocytogenes at Poultry Processing Plants     

Yoshimasa SASAKI  Mika HARUNA  Mariko MURAKAMI  Mizuho HAYASHIDA  Nao TAKAHASHI  Tetsuo URUSHIYAMA  Kazuo ITO  Yukiko YAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(1):129-132

  相似文献   

Induction of abalone larval metamorphosis by thyroid hormones   总被引：4，自引：0，他引：4  

Hirotatsu Fukazawa  Hirokazu Hirai  Hidenari Hori  Rodney D Roberts  Hauro Nukaya  Hitoshi Ishida  Kuniro Tsuji 《Fisheries Science》2001,67(5):985-988

  相似文献   

Viability of maternally heat-stressed mouse zygotes in vivo and in vitro   总被引：3，自引：0，他引：3  

Manabu OZAWA  Yukiko YAMASAKI  Miho HIRABAYASHI  Yukio KANAI 《Animal Science Journal》2003,74(3):181-185

Mammalian preimplantation embryos are susceptible to heat stress. This present study examined how maternal heat stress affects the development of mouse zygotes in vivo and in vitro. In Experiment 1, zygotes collected from female mice that were heat‐stressed for 12 h on day 1 of pregnancy were cultured in vitro. Maternally heat‐stressed zygotes developed normally to the two‐cell stage, but the majority of embryos failed to develop into morulae or blastocysts. In Experiment 2, pregnant mice were heat‐stressed on day 1 or from day 1 to day 3 of pregnancy. The number of living fetuses on day 14 of pregnancy was lower in heat‐stressed mice than in non‐stressed mice, but the difference was significant only in successively heat‐stressed mice. These results demonstrate that maternally heat‐stressed zygotes have reduced in vitro viability, but this phenomenon does not necessarily lead to embryo loss in the maternal environment.  相似文献   

Effects of changes in loading conditions and heart rate on the myocardial performance index in cats   总被引：1，自引：0，他引：1  

Hori Y  Uechi M  Indou A 《American journal of veterinary research》2007,68(11):1183-1187

OBJECTIVE: To evaluate the effect of changes in hemodynamics on the myocardial performance index (MPI) in cats. ANIMALS: 6 mixed-breed cats. PROCEDURES: Cats were anesthetized by administration of thiopental sodium; anesthesia was maintained by administration of isoflurane. Systolic arterial pressure and central venous pressure were measured by use of catheters, and heart rate was controlled by right atrial pacing. Afterload was increased by balloon occlusion of the descending aorta, and preload was increased by IV infusion of lactated Ringer's solution at a rate of 40 mL/kg/h. Echocardiography was performed for each condition. RESULTS: Atrial pacing significantly increased heart rate. The MPI did not change with heart rate. Arterial pressure and MPI increased significantly during aortic occlusion. The IV infusion increased fractional shortening but did not change the MPI. Multiple regression analysis revealed that the MPI was not affected by heart rate, systolic arterial pressure, central venous pressure, fractional shortening, or velocity of the E wave. CONCLUSIONS AND CLINICAL RELEVANCE: The MPI can be used to assess cardiac function in healthy cats. The MPI is independent of heart rate and systolic arterial pressure but is sensitive to changes in afterload.  相似文献