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本文研究木材真空干燥。内容包括木材真空干燥机的研制和木材真空干燥工艺的研究。试验结果表明,干燥机设计合理,技术性能良好,能够满足科学研究和小型生产的需要。通过实验,提出榆木、水曲柳、桦木和椴木的干燥基准,证明用真空干燥法干燥厚阔叶树材,具有干燥时间短、干燥质量好的优点。真空干燥具有研究价值,值得在一定范围内推广应用。 相似文献
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为研究沙棘鲜果渣在真空干燥条件下的干燥特性,进而确定适宜的工艺参数,笔者选用了不同的干燥温度、真空度和物料厚度对沙棘鲜果渣进行脱水干燥试验,测定不同干燥工艺条件下沙棘果渣的干燥特性,并对干燥后沙棘果渣的总黄酮和原花青素含量进行测定。试验结果表明,适宜的沙棘鲜果渣真空干燥工艺条件为:干燥温度60℃,真空度80 k Pa,物料厚度1. 0 cm.干燥后的沙棘果渣总黄酮含量最高达4. 98 mg/g,原花青素含量最高达35. 67 mg/g. 相似文献
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木材高频真空干燥及其应用前景 总被引:3,自引:0,他引:3
一、国内外发展概况及特点木材高频真空干燥是七十年代初首先在前苏联、美国、日本等国研究发展起来的一项先进的干燥技术,八十年代初开始应用于生产。美国的一家动力公司和日本的制造厂商,已推出高频真空干燥机的系列化产品,在欧、美及包括中国台湾在内的很多国家和地区推广应用。高频真空干燥的最大特点是木材干燥极为迅速。由于采用高频介电加热和在连续真空条件下作业,木材可在很短的时间内获得充分的热量,并在较低的温度下迅速干燥。一些用常规窑干法需要干燥数天乃至数十天的木料,采用高频真空干燥,仅需数小时或数十小时即可,干燥周期可缩短17 相似文献
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阐述了木材真空干燥的特点和国内研究现状,真空干燥可满足木材高品质、高效率、低成本的干燥目标,对推进行业节能减排工作、解决难干材和改性处理材干燥问题、提高干燥品质等均具有重要意义。对真空干燥木材的机理、研究进展、可能的研究方向进行评述,以期促进木材真空干燥科研工作和生产实践的共同发展。 相似文献
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几种室内盆花无土栽培繁育技术 总被引:2,自引:0,他引:2
实践表明:仙客来、美叶光萼荷、袖珍椰子、巴西木等室内盆花无土栽培时,播种、育苗基质用蛭石、沙;扦插用蛭石、珍珠岩;出苗和生根后移栽基质用泥炭1+蛭石1或泥炭1+珍珠岩1+沙1为宜,生长周期筛选的花卉通用型营养液浇灌生长良好。 相似文献
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球根花卉组织培养前预处理技术 总被引:1,自引:0,他引:1
球根花卉的组培技术相对其它类花卉较为困难 ,该文就其组织培养前的预处理技术进行了研究 ,初步得出了郁金香、百合、唐菖蒲 3种花卉不同外植体不同的处理技术。 相似文献
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In the Loess Plateau, soil desiccation has become a serious problem for forest and grass vegetation. Soil desiccation leads to the formation of a dried soil layer (DSL). This paper presents the results of research carried out in the central part of the Loess Plateau. The objective of the research was to produce a statistically supported set of indicators for evaluating soil desiccation of forestlands, to present a heuristic idea for soil desiccation and to supply scientific support for replacing farmland with forest or grass in the Loess Plateau and other regions of China. Here, we suggest that more attention should be paid to soil desiccation and its effects on the ecosystem of the region in the future. The results showed that natural Quercus liaotungensis forestlands (NQF) retained more water content than regrown Robinnia pseudoscacia forestlands (RRF). Significant DSLs were formed in the RRF but not in the NQF. A possible reason for no formation of DSL in NQF could be due to the presence of an arbor–shrub–herb stand structure and large humus and litter accumulation, which increased the natural forest's (NF) adaptability to the environmental conditions. Soil water content in the north-facing slope was significantly larger than in the south-facing slope. DSLs formed in the 0–500 cm layer of the south-facing slope. When slope gradient was greater than 25°, soil water content deceased sharply and showed significant difference compared with 9°, 15° and 20° (P < 0.05). So, we conclude that plant species, aspect and slope angle could be the predicators for the formation of DSLs. The analysis on soil physical properties of 0–60 cm layer indicated that plant species, aspect and slope angle also have significant effects on bulk density, porosity, plant-available capacity, and hydraulic conductivity, especially in the 0–20 and 20–40 cm layers. In the NQF and RRF with north-facing slope, soil physical properties were improved. 相似文献
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