期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
压缩空气泡沫系统与“一七”消防车
1
作者 顾向兵 陆昀 《中国消防》 2010年第10期41-43,共3页
介绍了压缩空气泡沫灭火系统及其优点,"一七"消防车的鲜明特点,以及针对"一七"
关键词 压缩空气 泡沫灭火系统 “一七” 消防车 特点 研究课题
原文传递
Different Understory Cultivation Techniques of Paris polyphylla Smith 被引量:4
2
作者 龚舟 龚范武 +1 位作者 彭静 罗先权 《Agricultural Science & Technology》 CAS 2016年第2期353-357,共5页
This study was conducted for the purposes of reducing consumption of wild resources of Paris polyphylla Smith, satisfying the market demand, saving the production cost, improving utilization rate of forest land, incre... This study was conducted for the purposes of reducing consumption of wild resources of Paris polyphylla Smith, satisfying the market demand, saving the production cost, improving utilization rate of forest land, increasing income of foresters and protecting ecological environment. Three types of fores{ land, i.e., the evergreen forest land (China fir forest), deciduous forest land (walnut forest) and shrub land (honey suckle forest.) were selected, and seeds and cut rhizomes of Paris polyphylla Smith produced in Bamian Mountain, Hunan, were used in the study on understory seedling raising and cultivation techniques. The results showed that: when using different propagation materials, seed propagation could be adopted to reduce the consumption of wild resources and provide a large number of seedlings, and was beneficial to large-scale planting; and when conducing seedling and plantlet raising followed by transplanting and direct seeding and planting using different propagation materials in large-scale understory cultivation, direct seeding/ planting was appropriate for saving save production cost with the advantage of early production. Among the 3 different types of forest land, the best choice was broad- leaved forest land, which could achieve better economic benefit because of con- forming with the ecological habit and growth and development law of Paris poly- phylla Smith. 展开更多
关键词 Paris polyphylla Smith PROPAGATION Seedling raising Direct seeding Understory cultivation
下载PDF
俗语词“三七二十一”的用法及其发展
3
作者 张文国 《现代语文》 2021年第3期4-8,共5页
俗语词“三七二十一”经历了一个产生、发展、稳定的过程。先秦至明代中期,“三七二十一”尚未凝固成一个俗语词,仍然是一个简单的乘法口诀。明代晚期,它才真正被作为一个俗语词来使用,一般出现在“搭配成分+(插入成分+)三七二十一”的... 俗语词“三七二十一”经历了一个产生、发展、稳定的过程。先秦至明代中期,“三七二十一”尚未凝固成一个俗语词,仍然是一个简单的乘法口诀。明代晚期,它才真正被作为一个俗语词来使用,一般出现在“搭配成分+(插入成分+)三七二十一”的结构中。清代初期至中期、清末民初时期,其用法得到了进一步的发展。到了现代汉语,最终稳定下来。其中,在清末民初时期,其用法的发展变化最为明显。 展开更多
关键词 “三七二十一” 俗语词 搭配成分 插入成分 清末民初
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部