排序方式: 共有31条查询结果,搜索用时 31 毫秒
1.
根据扁矩形消声通道二维消声理论替代一维理论导出的消声系数Φ(α),研究了障板消声结构的Φ(α)计算机程序和消声量与障板几何尺寸的关系 相似文献
2.
利用厌氧折流板反应器,分别考察了反应器启动,及不同COD/SO42-比值和硫酸盐负荷对模拟废水中SO42-去除的影响。实验在(32±0.1)℃,pH为6.06.5的条件下连续运行。结果表明:ABR经过约90 d的启动驯化阶段后,进水硫酸盐及COD浓度分别为1 500 mg/L和3 000 mg/L,水力停留时间为12 h条件下,硫酸盐去除率达到了92%。固定COD/SO42-比值为2.5时,随着进水SO42-浓度的增加(1 5006.5的条件下连续运行。结果表明:ABR经过约90 d的启动驯化阶段后,进水硫酸盐及COD浓度分别为1 500 mg/L和3 000 mg/L,水力停留时间为12 h条件下,硫酸盐去除率达到了92%。固定COD/SO42-比值为2.5时,随着进水SO42-浓度的增加(1 5003 500 mg/L),SO42-去除率逐渐下降,最低为60%,相反SO42-去除速率随着硫酸盐浓度的增加而增加,最大为7.98 kg(/m3.d);维持恒定的硫酸盐浓度(1 500 mg/L),逐渐缩短水力停留时间以提高反应器中硫酸盐负荷,SO42-去除率呈现先上升后下降的复杂变化趋势,当水力停留时间为6 h时,SO42-去除率达到最大;随着COD/SO42-比值的提高,硫酸盐去除能力增强,且反应体系对硫酸盐负荷的耐受能力也逐渐增强。 相似文献
3.
4.
5.
Methane fluxes were measured from three exposed tundra sites and four snowpack sites on the Fildes Peninsula in the maritime Antarctic in the summertime of 2002. The average fluxes at two normal tundra sites were −15.3 μg m−2 h−1 and −14.3 μg m−2 h−1, respectively. The fluxes from tundra site with fresh penguin dropping addition showed positive values with the average of 36.1 μg m−2 h−1, suggesting that the deposition of fresh droppings greatly enhanced CH4 emissions from the poor Antarctic tundra during penguin breeding periods. The summertime variation in CH4 flux was correlated with surface ground temperature and the precipitation. The correlation between the flux and PT0, which is the product of the precipitation and surface ground temperature, was quite strong. The diurnal cycle of CH4 flux from the tundra soils was not obtained due to local fluky weather conditions. The fluxes through four snowpack sites were also obtained by the vertical CH4 concentration gradient and their average fluxes were −46.5 μg m−2 h−1, −28.2 μg m−2 h−1, −46.4 μg m−2 h−1 and −17.9 μg m−2 h−1, respectively, indicating that tundra soils under snowpack also consume atmospheric CH4 in the maritime Antarctic; therefore these fluxes could constitute an important part of the annual CH4 budget for Antarctic tundra ecosystem. 相似文献
6.
The nitrous oxide emissions were measured at three tundra sites and one snowpack on the Fildes Peninsula in the maritime Antarctic in the summertime of 2002. The average fluxes at two normal tundra sites were 1.1 ± 2.2 and 0.6 ± 1.7 μg N2O m−2 h−1, respectively. The average flux from tundra soil site with penguin dropping addition was 3.7 ± 2.0 μg N2O m−2 h−1, 3–6 times those from the normal tundra soils, suggesting that the deposition of fresh droppings enhanced N2O emissions during penguin breeding period. The summer precipitation had an important effect on N2O emissions; the flux decreased when heavy precipitation occurred. The diurnal cycle of the N2O fluxes from Antarctic tundra soils was not obtained due to local fluky weather conditions. The N2O fluxes through four snowpack sites were obtained by the vertical N2O concentration gradient and their average fluxes were 0.94, 1.36, 0.81 and 0.85 μg N2O m−2 h−1, respectively. The tundra soils under snowpack emitted N2O in the maritime Antarctic and increased local atmospheric N2O concentrations; therefore these fluxes could constitute an important part of the annual N2O budget for Antarctic tundra ecosystem. 相似文献
7.
文章针对宝钢股份中厚板分公司炼铁厂煤干燥机除尘系统吸尘点冒灰,粉尘无组织排放超标的现象进行了测试分析,数据表明主要由除尘系统风量匹配不佳、吸尘点风量不合理造成。笔者通过不断调整阀门及风机档板开摩,测试调整后的风量、除尘性能、岗位粉尘浓度等参数,确定了一个合理的系统风量,不仅可以达到环境排放及职业卫生的要求,而且充分挖掘了除尘系统潜力,达到了节能降耗、经济运行的目的,同时对类似除尘系统风量匹配不佳、扬尘等问题也形成了有效的解决方案。 相似文献
8.
9.
赵淑珍 《中国特种设备安全》2013,(10):10-11
分析了垃圾发电锅炉入料口的正压释放问题,设计的风幕技术保证了此类循环流化床锅炉的安全运行,风幕技术改造结构设计合理,实用性强,值得在同类行业中推广应用。 相似文献
10.