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分析了橡木桶在中国葡萄酒酿造行业的使用现状和其对酿造工艺的影响,介绍橡木酒桶机械化生产技术以及在中国机械化生产的发展前景. 相似文献
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以岳阳市为例浅论园林大面积草坪的改造设计 总被引:1,自引:1,他引:0
由于城市大面积草坪存在功能性不强,管护成本高、容纳量小、生物多样性单一,景观观赏效果差的现实问题,本文从改造设计理念、立体配置模式、园林小品设计角度,提出改造设计方面的构思,旨在加强城市森林生态网络体系的建设,促进生态园林城市的发展。 相似文献
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试验对免炼山与炼山造林对当年生桉树生长的影响进行实地调查。结果表明:免炼山造林不影响桉树当年的生长量,具有操作方法简单,成本较低,符合可持续发展经营的要求。 相似文献
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LI Lu-lin 《甘肃林业职业技术学院学报》2007,(2)
本文通过树干注药补水,对不易成活的大规格珍贵濒危树种的移植成活率进行了探讨,试验结果表明:此种方法对提高大规格珍贵濒危树种苗木的成活率效果显著,且此种方法简单易行、成本低廉,在不易成活的珍贵濒危树种的移植保护及提高大规格工程绿化苗木的成活率工作中很有实用价值。 相似文献
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Prem Kant Jha Lohendra P. Dhakal Erik D. Kjær Jens-Peter Barnekow Lillesø 《Agroforestry Systems》2006,67(3):273-278
Shortage of fodder is a major constraint to livestock production in Nepal. The genetic variation in canopy biomass production
of Bauhinia purpurea L, a very important fodder species in Nepal, was estimated in a Breeding Seed Orchard in order to examine the potential of
simple, low input breeding. Substantial genetic variation could be observed suggesting that low input breeding based on simple
phenotypic selection can provide biomass gain in the order of 2–5% per year. Very high correlation was observed between stem
diameter (cross section area) and total biomass, making farmer based selection relevant. Jointly, these results suggest that
low input domestication is a promising option for improving fodder production in Nepal and thereby help to improve rural livelihood
and development. A multiple population approach is recommended. 相似文献
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以华山松(Pinus armandi)种子胚乳为实验材料,分别采取经典CTAB法、简易CTAB法和SDS法微量法提取华山松基因组DNA,并通过琼脂糖凝胶电泳、紫外分光光度计分析、标准差和标准误、卡方检验和SPSS软件显著性分析,将它们在DNA产量、质量和方法稳定性等方面的优缺点进行总结。得出结论:通过对数据进行卡方检验,所有数据都是差异是由方法所引起的,不是偶然误差所引起的;相比于经典CTAB法,SDS微量法和简易CTAB法的(OD260-OD320)/(OD280-OD320)标准差和标准误相差不大,数据相对精确,结果相对精确;通过SPSS软件分析分析,简易CTAB法和其他2种方法相比存在显著差异性,SDS微量法与经典CTAB法的P〉0.05,差异不显著,提取效果相差不大。综上所述:相比于简易CTAB法,SDS微量法与经典CTAB法的(OD260-OD320)/(OD280-OD320)都接近2.0,可能存在RNA污染污染,DNA的浓度也相对较低,SDS微量法与经典CTAB法不适合华山松胚乳DNA提取。简易CTAB法的(OD260-OD320)/(OD280-OD320)比率很接近1.80,不存在蛋白质和RNA污染,DNA纯度也最好,DNA浓度最高,比较适合华山松胚乳DNA提取。 相似文献
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国产MJ3210小型木工跑车带锯机锯解正交试验分析 总被引:1,自引:0,他引:1
采用正交试验设计法,对国产MJ3210小型木工跑车带锯机的锯解质量进行研究。通过实测马尾松锯材尺寸偏差、表面粗糙度等参数,得到其最佳的进料速度、锯解厚度和锯卡高度的组合方案。结果表明,该设备具有结构简单、出材率高、锯解精度高、质量好、成本低和生产效率高等优点。 相似文献
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介绍了一种用频率跟踪法测量木工机床切削功率的新方法.测试并分析了利用电量隔离传感器与工控机界面对木工铣床铣削杨木板材的切削功率进行频率跟踪的方法,结果表明,该方法实用价值较高,具有操作简便、准确性强、可靠性高、互换性好、成本低等特点,可用于木工机床的研发和检测工作中. 相似文献
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Landscape contexts with high complexity may promote diversity of natural enemies, although the effect on biocontrol remains under discussion. Although biocontrol of Sitobion avenae is a well-studied system, little is known about the temporal effect of landscape context on the natural enemy assemblages. In a previous study, we showed a positive effect of predators in the decline of aphids; however, this effect had a temporal pattern responding to different landscape contexts. We study here two contrasting agricultural contexts, high landscape complexity with low intensification and low complexity with high intensification. Abundance and diversity of parasitoids was examined via a molecular approach, using a combination of diagnostic multiplex and singleplex PCR assays to test field-collected samples of S. avenae with genus- and species-specific parasitoid primer pairs. Temporal population dynamics were analyzed and differences related to these two contexts were observed. Parasitism rates were greater in the mid-sampling dates in high intensification simple landscapes, which were not observed for the low intensification complex landscapes. According to our results, we suggest that the greater landscape complexity in combination with a low agricultural intensification increase negative interactions for parasitoid population built-up; however, early predation by coccinellids was able to control the aphid populations. In contrast, under a simple landscape context with a high agricultural intensification, our results suggest an important role of parasitism with a complementary effect of late predation. We highlight the importance of different natural enemy guilds and their temporal dynamics under contrasting agricultural settings to further understand the relationship between functional diversity and biological control. 相似文献
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基于ZigBee技术的无线水表的设计,将PIC18F4620单片机作为主控MCU,采用ZigBee技术的典型芯片CC2430实现无线网络的传输控制。该设计实现了小区的用水量实时保存,系统具有低成本、低功耗、高可靠、组网简单灵活的优势。 相似文献