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黑龙江冬季寒冷且时间长,各无人值守机房在冬季将消耗大量电能来取暖。由于无线移动基站很多,采取节能方式将降低运行成本。为此,介绍了一种节能和补偿热量方式,其实际应用效果显著。 相似文献
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浅谈发酵床养猪法的优缺点 总被引:3,自引:1,他引:2
发酵床养猪是近年从日本、韩国等地处亚寒带地区国家引进的一项养猪技术,又称“自然养猪法”或“生物环保养猪法”,利用有机垫料建成一个发酵床,通过添加商业化的微生物,猪排泄出来的粪便被垫料掩埋,水分被发酵过程中产生的热蒸发,猪粪尿经微生物菌的发酵后,得到充分的分解和转化,达到无臭、无味、无害化的目的,是一种无污染、无排放的、无臭气的环保养猪技术。 相似文献
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1制定切合实际的引种计划
根据生产需求和目的,制定切实可行的引种计划和方案,所引品种用途明确,需求一致。所引畜禽产地的环境和自然条件必须与当地的环境自然条件大体一致。如热带动物品种寒带就不能饲养,而寒带地区的品种在热带就难于饲养,气候干燥地域的动物难于适应雨量充沛湿润地区的环境条件等。 相似文献
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The current trend of forest management in many countries is reduced use of clear-felling and planting, and increased use of continuous cover management. In Finland, the new forest act of 2014 made all types of cuttings equally allowable on the condition that if the post-cutting residual stand basal area is too low, the stand must be regenerated within certain time frame. Forest landowner can freely choose between evenand uneven-aged management. This study developed a method for optimizing the timing and type of cuttings without the need to categorize the management system as either even-aged or uneven-aged. A management system that does not set any requirements on the sequence of post-cutting diameter distributions is called any-aged management. Planting or sowing was used when stand basal area fell below the required minimum basal area and the amount of advance regeneration was less than required in the regulations. When the cuttings of 200 stands managed earlier with even-aged silviculture were optimized with the developed system, final felling followed by artificial regeneration was selected for almost 50% of stands. Reduction of the minimum basal area limit greatly decreased the use of artificial regeneration but improved profitability, suggesting that the truly optimal management would be to use natural regeneration in financially mature stands. The optimal type of thinning was high thinning in 97–99 % of cases. It was calculated that the minimum basal area requirement reduced the mean net present value of the stands by 12–16 % when discount rate was 3–5 %. 相似文献
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阐述寒带造林中 ,环境因子对不同树种、苗木成活的影响 ;分析了环境因子在不同时间和季节中的变化 ,设想了使苗木个体适应环境的基本方式 ,为寒带造林技术提供参考。 相似文献
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蓝莓以极高的营养价值和独特的保健功效被称为"世界水果之王"。蓝莓抗氧化能力在水果和蔬菜中最强,抗氧化值(ORAC)高达2400/100克,联合国粮农组织(FAO)将其列为"人类五大健康食品"之一。我国地域广大,有热带、亚热带、温带和寒带气候区,并有湿润海洋性和干旱大陆性气候,更有平原、丘陵、山地和高原。山区多、林草茂盛,并有多种野生蓝莓原生态分布。试验表明,现已引进的半 相似文献