Interspecific competition effects on phosphorus accumulation by Hydrilla verticillata and Vallisneria natans

The competition between submersed plants has been recognized as an important factor influencing the structure of plant communities in shallow lakes. The ability of different species to take up and store nutrients from the surrounding ambience varies, and hence plant community structure might be expected to affect the cycling of nutrients in lake ecosystems. In this study, the uptake of phosphorus by Hydrilla verticillata and Vallisneria natans was studied and compared in monoculture and competitive mixed-culture plantings. Results showed that for both studied species the phosphorus concentrations of different tissues and of whole plants was unaffected by competition. However, the quantity of phosphorus accumulated by whole plants of H. verticillata was significantly higher in mixture culture than in monoculture, while that of V. natans was lower in the mixed culture. The results indicated that H. verticillata has a competitive advantage over V. natans, when the two species are grown in competition, and is able to accumulate a greater quantity of phosphorus.     

Modification of Ce02-ZrO2 catalyst by potassium for NOx-assisted soot oxidation

Potassium-modified ceria-zirconia catalyst was synthesized by wetness impregnation method. The ageing treatment was performed in static air at 800℃ for 20 hr to evaluate the thermal stability of the catalyst. The catalysts were characterized by X-ray diffraction,BET surface area, oxygen storage capacity, NOx-temperature programmed desorption and soot-temperature programmed oxidation measurements. By introduction of potassium, the maximum soot oxidation rate temperature (Tm) of the ceria-zirconia based catalyst decreased from 525 to 428℃ in the presence of NO under a loose contact mode. The shift of Tm of the K-modified catalyst after ageing is only 15℃. The enhanced activity of the aged catalyst mainly lies in the promotional effect of potassium on the NOx/oxygen storage cacity as well as the soot-catalyst contact.     

动力与热力抬升对烟气抬升高度的影响分析

通过模式选择和计算,得出烟气抬升高度的增加与动能和热能的关系,表明当烟囱出口处风速分别为3 m/s、2 m/s和1 m/s时欲增加同样大小的烟气抬升高度,需要的动能比热能要高,结论认为烟气的热力提升比动力提升的贡献大。     

臭氧处理循环冷却水节能减排效益分析

文章基于臭氧(O3)处理法处理循环冷却水因可以同时达到阻垢脱垢、缓蚀、杀菌等多重功能,其在国外已得到广泛应用,同时国内也逐步普及应用的环境下,结合国内外长期的工程实践经验,从节水、节能、减排和公共卫生效益四个方面,详细分析了臭氧处理循环冷却水所带来的巨大经济效益、社会效益和环境效益。     

福建省能源消费碳排放和低碳能源发展研究

能源消费导致的碳排放对全球气候变化带来严峻挑战.区域经济迅速发展,不但对区域能源安全提出挑战,也对碳减排提出新的课题.文章总结了改革开放以来福建省能源消费的特点和趋势,计算由能源消费引起的碳排放量.研究表明,虽然碳强度有显著下降,但是碳排放总量增长比较明显,特别是从2000年开始,增长幅度加大.利用Kaya恒等式对碳排...     

青岛华威风电场风能资源分析

根据华威风电场2008年4月1日-2009年3月31日一整年的测风仪测风资料,对风电场的风能资源各参数进行了详细地计算和分析,对风电场的风能资源进行评价,为当地的风能开发提供分析基础。     

电动交通工具的污染减排及对策

燃油交通工具是城市温室气体的重要来源之一,因此使用电动交通工具成为解决城市污染减排的重要措施.文章就正确认识电动交通工具污染减排的作用,蓄电池的生产管理、回收利用等进行了讨论,并提出了相应的对策和建议.     

论水处理工程中的节能

人们在污水处理厂的建设中对污水处理工艺的先进性、可靠性以及工程投资大小考虑较多,而对污水处理厂建成后的运营管理考虑较少,因而造成许多污水处理厂建成后由于运营成本过高而不能正常运行。从能耗角度出发,分析造成运行成本高的主要原因以及相应采取的措施。     

抽水蓄能电站工程建设中生态环境监理工作实践探讨

水利水电工程建设是促进国家经济发展的重要建设项目之一,抽水蓄能电站工程建设的重要性正在不断凸显。抽水蓄能电站工程的建设与生态环境有着密切的关系,由于抽水蓄能电站工程长期大规模的开发利用破坏了周边生态环境的稳定,加强工程建设中的环境监理工作是将生态破坏程度降到最低的必然要求。以抽水蓄能电站为实例,通过制定科学合理的环境监理方案,将生态环境监理要点落实到施工建设当中,以期最大限度地减少对生态环境的破坏。     

农村沼气在北方农业源减排中的应用浅析

农村沼气作为一种特殊的清洁能源,在沈阳市农村节能减排、应对气候变化和发展低碳经济、促进新农村建设方面发挥了巨大的作用。本文通过对沼气工程在北方地区应用的阐述,力图推动北方农村沼气在农业源减排工作中的应用。