Efficiency of gypsum application to acid Andosols estimated using aluminum release rates and plant root growth     

Tadashi TAKAHASHI  Yuya IKEDA  Hitomi NAKAMURA  Masami NANZYO 《Soil Science and Plant Nutrition》2006,52(5):584-592

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Characteristics of a Pacific herring Clupea pallasii spawning bed off Minedomari, Hokkaido, Japan     

Hiroshi  HOSHIKAWA  Hisami  KUWAHARA  Ken-ichiro  TAJIMA  Tadashi  KAWAI  Tomonori  KANETA  Fujinori  TSUDA 《Fisheries Science》2004,70(5):772-779

ABSTRACT:   The spawning bed selection of herring Clupea pallasii off Minedomari, Atsuta, on the west coast of Hokkaido, Japan, is discussed in relation to the topography of the rocky shore and wave conditions during the spawning season. From 1998 to 2003, herring have spawned their eggs mainly on the leaves of the seagrass Phyllospadix iwatensis Makino in almost the same site on the rocky shore off Minedomari in the Atsuta area. The site is connected to a valley-like feature offshore. Wave conditions were surveyed at Minedomari during the spawning season in 2000 and the wave height was estimated from 1998 to 2003, except for in 2000, using the correlation of wave height between Minedomari and Ishikari Bay New Port, approximately 18 km south-west of Minedomari. Herring spawned under calm conditions, during which the wave height was approximately 0.5 m off Atusta and Aoshima and was 0.18–1.28 m off Minedomari. The distribution of water particle velocity on the sea bottom surface as a result of ocean waves off the Minedomari area, which was estimated based on the wave height and the topography of the coast, suggested herring could swim easily into the shallower area along the valley-like feature off Minedomari. Therefore, topographical features are thought to be one of the reasons why herring have used Minedomari as a spawning bed. Additionally, seepage of freshwater from the bottom, which was observed in this area, could also be the reason why herring spawn in Minedomari repeatedly.  相似文献   

Effective use of the TSPY gene‐specific copy number in determining fetal DNA in the maternal blood of cynomolgus monkeys          下载免费PDF全文

Lubna Yasmin  Jun‐ichiro Takano  Tadashi Sankai 《Animal Science Journal》2016,87(8):1034-1040

Since the available concentration of single‐copy fetal genes in maternal blood DNA is sometimes lower than detection limits by PCR methods, the development of specific and quantitative PCR detection methods for fetal DNA in maternal blood is anticipated, which may broaden the methods that can be used to monitor pregnancy. We used the TaqMan qPCR amplification for DYS14 multi‐copy sequence and the SRY gene in maternal blood plasma (cell‐free DNA) and fractional precipitated blood cells (cellular DNA) from individual cynomolgus monkeys at 22 weeks of pregnancy. The availability of cell‐free fetal DNA was higher in maternal blood plasma than that of cellular DNA from fractional precipitated blood cells. There was a significantly higher (P < 0.001) mean copy number of fetal male DYS14 from maternal plasma (4.4 × 10⁴ copies/mL) than that of detected fetal cellular DNA from fractional blood cell pellets. The sensitivity of the DYS14 PCR assay was found to be higher than that of the SRY assay for the detection of fetal DNA when its presence was at a minimum. The DYS14 assay is an improved method for quantifying male fetal DNA in circulating maternal blood in the primate model.  相似文献   

Effect of annual rings on abrasive wear property of wood     

Tadashi Ohtani  Takao Yakou  Shigeru Kitayama 《Journal of Wood Science》2002,48(4):264-269

In this study we investigated the abrasive wear property of Douglas fir (Pseudostuga menziesii Franco) on abrasive paper using test specimens with various dimensions and annual ring widths. The effect of the annual rings on the abrasive wear property of Douglas fir was clarified from the relation with the compression strength of the wood specimens. The dispersion of the wear coefficient, which was calculated as the wear volume divided by the friction distance and the load applied to the friction surface, varied when there were fewer than approximately three annual rings in the specimen, as did the compression strength. As clarified from these results, it was found that the effect of the annual rings on the abrasive wear and compression properties of Douglas fir is closely related to the earlywood/ latewood ratio.Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000  相似文献   

Performance of coated carbide tools in turning wood-based materials: Effect of cutting speeds and coating materials on the wear characteristics of coated carbide tools in turning wood-chip cement board     

Wayan Darmawan  Chiaki Tanaka  Hiroshi Usuki  Tadashi Ohtani 《Journal of Wood Science》2001,47(5):342-349

This paper reports on the performance of coated carbide tools in turning wood-chip cement board. The coating materials studied were titanium carbonitride (TiCN), titanium nitride (TiN), chromium nitride (CrN), and titanium nitride/aluminum nitride (TiN/AlN), which were synthesized on the P30 carbide substrate. The aim is to investigate the effect of coating materials and cutting speeds on the wear characteristics of the coated carbide tools. Cutting tests were performed when turning wood-chip cement board at cutting speeds of 30, 40, 50 and 60 m/s, a depth of cut of 1mm, and a feed of 0.05 mm/rev. The results of the study show that the coated carbide tools provided better performance than the P30 carbide tool, especially in terms of reducing the progression of the wear rate and clearance wear. The TiN/AlN-coated carbide tool showed the smallest increase in both wear rate and clearance wear with an increase in cutting speed and had the longest tool life among the coated carbide tools investigated. Though the TiCN-coated carbide tool was observed to have a low wear rate and low clearance wear for cutting speeds of 30 and 40m/s, when the cutting speeds were >50m/s its wear rate and clearance wear were almost the same as those of CrN-and TiN-coated carbide tools, which had high values for these parameters.Part of this paper was presented at the 21st IUFRO World Congress, August 2000, Kuala Lumpur, Malaysia  相似文献   

The four-line model of the Triangular Running Skyline system: Scale model test     

Yasushi Suzuki  Tadashi Kawai  Kouichi Kanzaki 《Journal of Forest Research》1996,1(4):187-193

The four-line model of the Triangular Running Skyline (TRS) system is the theory generalized from the previous TRS theory to treat the main and slack-pulling lines separately. The previous theory,i.e., the three-line model, treated the main and slack-pulling lines as a single line to simplify the solution. The first part of this study developed numerical procedures for the four-line model. In this paper, to empirically ascertain the accuracy of the four-line model theory, a series of static equilibrium tests was carried out using a reduced scale model of the TRS system. The result proved that the theory of the four-line model has the same accuracy as that of the three-line model. However, the result also proved that the carriage may have to be located lower than the designated height. Thus, it has been proved that the development of a certain adjusting method is necessary to move the carriage of the TRS system closer to the designated point. A part of this paper was orally presented at the Second Annual Meeting of the Japanese Forest Engineering Association, November 18, 1995, Tokyo. This English title is a tentative translation from the original Japanese by the authors of this paper.  相似文献   

Shear tests of double shear plate connector joints in sugi—Japanese larch composite glulam beams     

Yasushi Nakashima  Masaki Harada  Tomoyuki Hayashi  Masahiko Karube  Tadashi Higashino 《Journal of Wood Science》2006,52(1):44-50

To study the shear strength of structural joints in sugi (Cryptomeria japonica D. Don) — Japanese larch (Larix kaempferi Carriere) composite glulam beams using structural connectors with double shear plates, shear tests were conducted on two types of joint (post-beam and girder-beam). Two types of the composite beam (240 and 300 mm depth) were prepared for the tests. Ordinary sugi glulam beam and Japanese larch glulam beam were also used as control specimens. The load—displacement curves of joints in composite beams were somewhere between those of sugi and Japanese larch glulam beams. The shear strength of joints in composite beams was higher than that in the sugi glulam beam control. However, the allowable loads of the joints in composite beams were lower than those in the sugi beam with 240 mm depth. Large variation of maximum load of the joints in the composite beams resulted in lower allowable load.  相似文献   

Effects of simulated drought stress on the fine roots of Japanese cedar (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) in a plantation forest on the Kanto Plain,eastern Japan     

Bohdan Konôpka  Kyotaro Noguchi  Tadashi Sakata  Masamichi Takahashi  Zuzana Konôpková 《Journal of Forest Research》2007,12(2):143-151

Drought stress was simulated in a 28-year-old Japanese cedar plantation (Kanto Plain, Japan) between April and October 2004 by removing throughfall using rain shelters. Changes in fine-root parameters caused by this drought treatment were examined by sequential soil coring. Drought effects on fine roots were analyzed separately for particular soil depths (0–5, 5–15, and 15–25 cm) and root diameters (<1 and 1–2 mm). Generally, fine-root biomass and root tip numbers decreased by the drought treatment. Drought stress was most intense for fine roots in the topsoil and weakest for fine roots in the deepest soil layer. Fine roots less than 1 mm in diameter were affected more severely than 1- to 2-mm roots. The effect of drought treatment was most remarkable for the number of white root tips, which decreased to 17% of the control at the soil depth of 0–5 cm. These results suggest that white root tip is the most suitable indicator of drought stress. Simulated drought reduced production of fine roots less than 1 mm and 1–2 mm in diameter. Fine-root mortality was stimulated for roots less than 1 mm, but not for 1- to 2-mm roots. These results suggest that fine roots with larger diameters can survive drought stress at a level simulated in this study, but processes of fine-root production were inhibited regardless of the diameter classes. The duration of drought stress and phenology of fine roots should also be considered in diagnosing the effects of drought on fine-root parameters.  相似文献   

Development of room-temperature curing aqueous emulsion-type acrylic adhesive II: effect of monomer composition on the final adhesive strength     

Atsushi Mori  Kazuhisa Tashiro  Kyoko Makita  Masahiro Takatani  Tadashi Okamoto 《Journal of Wood Science》2005,51(1):38-41

In a series of studies, development of a new aqueous emulsion-type adhesive for use with wood or paper, which does not release formaldehyde or volatile organic solvents, was attempted. For the purpose of increasing both initial and final adhesive strengths, we selected a system consisting of acrylic monomers copolymerized with functional monomers such as diacetone acrylamide and some cross-linking agents such as dihydrazide or polymeric methylene diphenyl diisocyanate (pMDI). It was found that dihydrazide cross-linker was effective for both the initial and final adhesive strengths, suggesting contribution of hydrazone bonds to the bonding strengths. Cross-linking with pMDI might be slow and was not important in the initial bonding. However, its cross-linking effect might develop gradually, because the adhesive showed good final strengths using pMDI as a cross-linker.  相似文献   

Preparation of polyols from methyl-α-d-glucoside and cyclic esters for design and fabrication of biodegradable polyurethane foams     

Mariko?YoshiokaEmail author  Atsushi?Miyata  Tadashi?Yagi  Yoshiyuki?Nishio 《Journal of Wood Science》2004,50(6):511-518

A ring-opening polymerization of cyclic esters -caprolactone (CL) and/or l-lactide (LACD) was carried out in the presence of methyl--d-glucoside (m-Glc) as an activated substrate and tin(II) 2-ethylhexanoate (SnEht₂) as a catalyst. This led to successful synthesis of an armed polyester polyol with m-Glc as the core. These polyols were characterized through gel permeation chromatography, hydroxyl value assessment, differential scanning calorimetry, and viscosity measurements. It was clarified that the thermal properties and tractability of the synthesized polyols are closely related to the structural characteristics of the side chain polyesters, such as their length and chemical composition. Polyurethane foams were also prepared by mixing an appropriate amount of the polyols with diphenyl methane diisocyanate, a foaming agent (water), and other additives, and their mechanical properties were examined. Two polyurethane foams manufactured from polycaprolactone-polyols that were synthesized at a CL/m-Glc ratio of 2 or 5, were used in a biodegradation test in a closed system of activated sludge suspension. Evidence of their biodegradation is presented based on data showing oxygen consumption by the pulverized samples.  相似文献