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111.
介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠 相似文献
112.
影响生物脱氮除磷的因素 总被引:2,自引:0,他引:2
对生物脱氮除磷的基本原理作了简要分析,因其脱氮和除磷受多种因素影响,择其主要影响因素进行综述,以便为工程应用提供依据。 相似文献
113.
视频点播是近两年在Internet和宽带网上新兴的多媒体技术,其优秀的实时性和良好的交互性,使得这一新技术在Internet尤其是宽带网上得到迅速推广.本文介绍了视频点播系统的原理、开发和应用,并列举了一个具体案例来说明. 相似文献
114.
中小企业财务管理存在的问题与战略对策 总被引:3,自引:0,他引:3
钟开威 《湖南环境生物职业技术学院学报》2005,11(2):161-164,172
中小企业是国民经济中一支重要的经济力量,在我国发展社会主义市场经济中发挥着重要的作用.财务问题是所有企业成败的关键,对中小企业尤其如此.本文从简述我国现阶段中小企业财务管理现状人手,揭示当前中小企业财务管理存在的问题.结合实际,分析其发生、存在的原因,并为解决这些问题,提出了相应的战略对策. 相似文献
115.
固体废弃物渗滤液组分动态变化预测 总被引:2,自引:0,他引:2
渗滤液(Leachate)是城市固体废物填埋场(MSWLF)污染环境的主要来源之一,因此掌握其水质变化规律是研究填埋场对环境污染的首要问题。渗滤液的主要来源是大气降水,使用垃圾淋滤的方法模拟大气降水,利用实验结果建立模拟模型,揭示了渗滤液组分随降水的变化规律。可以预测垃圾填埋后渗滤液污染组分的浓度变化。为研究填埋场渗滤液组分变化及确定其处理对策提供了理论依据。 相似文献
116.
丰丽林 《湖南环境生物职业技术学院学报》2007,13(3):53-55
运用位移监控信息、土体平衡原理、护壁桩支撑设计原理指导深基坑支护适应基坑深度变大的难题,具有施工方便、经济、安全的、工期短等特点,为在闹市区深基坑支护施工提供了经验.图1,表1,参7. 相似文献
117.
Pillar building in the fiddler crab Uca beebei: evidence for a condition-dependent ornament 总被引:2,自引:0,他引:2
Patricia R.Y. Backwell Michael D. Jennions John H. Christy Ursula Schober 《Behavioral ecology and sociobiology》1995,36(3):185-192
In the fiddler crab (Uca beebei) males build a small mud pillar next to their burrow which increases their attractiveness to females. Three hypotheses were tested to explain inter-male variation in pillar-building. (1) The benefits of pillar-building are density dependent. The experimental addition of vertical structures did not support this hypothesis as there was no change in the level of pillar-building. (2) There are two classes of males (pillar-builders and non-pillar-builders). This could either be due to an alternative mating strategy, or because pillar building is age or size-dependent. There was also no support for this hypothesis. (3) Pillar-building is an honest signal of male quality dependent on body condition. A food supplementation experiment was performed. Addition of food affected several aspects of male behaviour and resulted in a two fold increase in the number of pillars built between control and food treatments (P < 0.001). However, the percentage of males building pillars did not increase significantly. Pillar building in this species has been attributed to sensory exploitation. Our results indicate that a trait which may well have evolved through sensory exploitation also appears to be condition-dependent. We emphasise that showing that an ornament or behaviour is condition-dependent does not necessarily mean that it evolved through good gene processes. However, in terms of its current selective value, pillar building may be maintained through female choice because it acts as a signal of male condition. 相似文献
118.
Xiao Gang Ni Mingjiang Chi Yong Jin Yuqi Zhang Jiaquan Miao Qi Cen Kefa 《Frontiers of Environmental Science & Engineering in China》2007,1(4):498-503
In order to eliminate secondary pollution caused by municipal solid waste (MSW) incineration, a MSW gasification and melting
process is proposed. The process is expected to reduce the emission of pollutants, especially heavy-metals and dioxins. In
this paper, the combustible components of MSW and simulated MSW were gasified in a lab-scale fluidized bed at 400°C–700°C
when the excess air ratio (ER) was between 0.2 and 0.8. The experimental results indicated that the MSW could be gasified
effectively in a fluidized bed at approximately 600°C–700°C when excess air ratio was 0.2–0.4. The melting characteristics
of two typical fly ash samples from MSW incinerators were investigated. The results indicated that fly ash of pure MSW incineration
could be melted at approximately 1,300°C and that of MSW and coal co-combustion could be melted at approximately 1,400°C.
When temperature was over 1,100°C, more than 99.9% of the dioxins could be decomposed and most of the heavy-metals could be
solidified in the slag. Based on the above experiments, two feasible MSW gasification and melting processes were proposed
for low calorific value MSW: (1) sieved MSW gasification and melting system, which was based on an idea of multi-recycle;
(2) gasification and melting scheme of MSW adding coal as assistant fuel.
__________
Translated from Environmental Science, 2006, 27(1): 69–73 [译自: 环境科学] 相似文献
119.
针对煤气化废水的特点,通过投加Fe3 、PO43-的方法来强化多阶段水解-好氧工艺处理煤气化废水的能力,不加Fe3 、PO43-时,CODcr总去除率为78 88%,出水CODcr仍高达931mg/l,当投加Fe3 、PO43-后,出水CODcr降到245mg/l,去除率达到93 93%。 相似文献
120.
生物质转化利用技术研究进展 总被引:5,自引:0,他引:5
综述了当前国内外生物质转化利用技术的原理和特点,分析了生物质转化利用技术的研究现状以及存在的问题,展望了生物质利用的发展前景。 相似文献