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单板中阻燃剂载药量的多少直接影响着阻燃胶合板的阻燃性能。单板进行阻燃剂浸泡过程中,影响其载药量的因素较多,如单板初含水率、浸泡时间、阻燃剂浓度及阻燃剂温度等。对影响单板载药量的因素做了初步试验研究并对试验结果进行了分析,同时结合国内实际生产情况给出了建议。 相似文献
84.
Masaki Jinkawa Hirokazu Yamaguchi Kuniaki Furukawa Toshiaki Satake Hiroshi Kobayashi 《Journal of Forest Research》2006,11(2):77-88
For monorail systems, it is very important to ensure the safety of the ground structure. We developed a tram car for slopes
that utilizes the mechanism of the monorail and analyzed the stress of the ground structure that had double rails. First,
we divided the ground structure into seven components, and formulated a procedure for calculating the stress of the ground
structure. As a result, the stress that acts upon the main rail and the main rail connecting part was near the allowable stress,
and each calculated value was within the allowable stress. We measured the stress by running the vehicle, and compared the
measured values with the calculated values. As a result, some measured values were larger than the calculated values. However,
the ratio of measured value to allowable stress was 90% or less. Finally, we calculated the static loading coefficient for
each part, results of which were as follows: main and subrail: 1.1; rail connection part and prop foundation part: 1.0; rail
installation part: 1.3. In the recalculations, it became clear that the recalculated values exceeded the allowable stresses.
These results suggest that we need to review the ground structure materials. 相似文献
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Koji Yoshida Shoko Inaba Chisato Takenaka Takafumi Tezuka 《Journal of Forest Research》2005,10(2):157-161
To clarify the nutrient status in momi fir (Abies firma Sieb. et Zucc.) seedlings under complex stress conditions of acid fog with soil acidification or nitrogen loading, we exposed seedling shoots to simulated acid fog (pH 3) and simultaneously loaded the soil with acid or excess nitrogen for 17 months. Proton and nitrogen loading reduced K concentration in soil, but these treatments had little effect on the nutrient status of fine roots in momi fir seedlings. Acid fog exposure resulted in reduced concentrations of Mg, Al, and Fe in current-year needles and Mg, Al, Cu, Fe, and Zn in 1-year-old needles. The complex effects of acid fog exposure with proton or nitrogen loading on nutrient status were relatively slight. However, elements such as Al and Cu notably reflect the effects of proton loading. These results show that the nutrient status of trace elements, rather than major elements, in needles of momi fir seedlings is sensitive to exposure to acid fog or proton loading. 相似文献
87.
Effect of temperature and compression on the mechanical behavior of steam-treated wood 总被引:2,自引:0,他引:2
The mechanical behavior of steamed spruce wood changes dramatically with compression along the grain, the change being much more moderate perpendicular to the grain. The stiffness decrement due to increased temperature is greatest in the tangential material direction. The stiffness decrement due to compression is greatest along the grain. Compression to 80% compressive strain at 131°C inverts the order of the material directions regarding stiffness, the stiffness being the least along the grain. Plastic strain due to compression is greater at higher temperatures. The compression-induced decrement of stiffness along the grain is greater at higher temperatures, but the off-axis decrement of stiffness is less at higher temperatures. 相似文献
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为评价莪术油/(麦芽糊精-Povacoat)微囊的质量,建立了硫酸香茅醛显色测定其载药量和包封率的方法。对莪术油乙醇溶液进行波长扫描,确定508nm为最大吸收波长,显色稳定性试验表明,反应液在150min内吸光度较稳定。莪术油检测浓度在0.199 2μg/mL~9.960μg/mL范围内线性关系良好(A=0.094 7C-0.001 2,r=0.999 3),微囊的载药量测定和包封率测定的方法回收率分别为99.6%和99.1%。经测定,3批微囊的载药量为51.5mg/g~53.2mg/g,包封率为88.2%~90.7%。 相似文献