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101.
102.
论述了给水钢管外腐蚀的原因,并就采用阴极保护技术来防止给水钢管外腐蚀的具体措施进行了介绍,指出在使用阴极保护措施的同时应重视管壁保护涂层的作用。 相似文献
103.
An electrochemical model for an upflow dual-chambered microbial fuel cell (MFC) process is proposed in this study. The model was set up on the basis of the experimental results and the analysis of biochemical and electrochemical processes in the MFC biocatalysed with anaerobic aged sludge and alternatively fuelled with a synthetic acetate-based and actual domestic wastewaters. Simulation of the process shows that the model describes the process reasonably well with correlation coefficients higher than 0.97. The analysis of model simulation illustrates how the current output depends mainly on the substrate concentration as well as other main variables. The relationship between the current output and over-voltage is revealed by the modelling study. For acetate-based wastewaters with initial chemical oxygen demand (COD) concentrations of 350, 700, 1050, and 1400 mg/L, maximum observed power densities were 290, 405, 448, and 525 mW/m2 associated with maximum COD removals of 84%, 88%, 83%, and 82%, respectively. 相似文献
104.
The influence of pH on phosphate release from lake sediments 总被引:3,自引:0,他引:3
Paul C.M. Boers 《Water research》1991,25(3)
pH is believed to be an important regulating factor for the release of phosphate from freshwater sediments. Usually, this is demonstrated in laboratory experiments using intact sediment cores and pH regulation of the overlying water by means of NaOH additions. This technique and a pH regulation technique by means of CO2-stripping were compared. The first method resulted in a 10-fold increase in release rate at pH 9.5 compared to the rate at pH 8.3. The stripping technique yielded only a doubling of the release rate at pH 9.3. Measurements of pH profiles in the sediment in experiments performed at pH 8.3 and 9.0 proved that the enhanced phosphate release when using NaOH for pH regulation is mainly an artifact caused by an increased alkalinity in the water column and the upper sediment layers, resulting from the NaOH additions. 相似文献
105.
混凝土中钢筋锈蚀的电化学检测方法 总被引:14,自引:1,他引:14
综合分析了混凝土中钢筋锈蚀的非破损检测方法,在此基础上,着重剖析了常用电化学检测方法的优缺点、适用场合及其应用情况,指出了今后的发展方向。 相似文献
106.
组合城市热网管道的建设,探讨了长距离大管道安装后怎样进行水压试验的问题,阐述了理论计算过程和严密性水压试验方法,总结了在太原集中供热二电工程14km管网主干线严密性试验的成功经验。 相似文献
107.
SHUJI MORIYAMA YUJI SHAEMI DON-GUN NAM SATOSHI TANAKA NAOMI OKAZAWA DING Wen-ting 《消防科学与技术》2006,25(3):324-333
介绍了地铁站内烟气流动和控制的试验和数值研究。在三个真正地铁站内利用甲醇油池火作为燃料进行了试验,用所获得数据来验证地铁站火灾数值模型,并进一步检验其烟控系统的性能。在站内使用了制量烟气流动模型,再现了最简单条件下每个站点的试验结果,然后把结果跟其他试验条件下的试验结果进行了比较。最后,用模型预测更复杂火灾的烟气流动情况。另外,还讨论了地铁系统的有效设计和火灾安全设施的正常运作情况。通过限制内饰面材料的燃烧性能或者安装自动喷淋系统都可以有效控制热释放速率,且在站点两端开设逃生路线、站台和地铁隧道直接卷帘的正常启动等可有效保证安全疏散。 相似文献
108.
109.
An analysis of fire spread during four large-scale fire tests that were performed in the Runehamar tunnel in Norway is presented.
The fire loads consisted of mock-ups simulating a Heavy Goods Vehicle (HGV) trailer. The fire spread downstream of the HGV
trailer mock-ups was studied, both to large targets with the same type of commodities as used in the trailer mock-up for each
tests, and to small pieces of wood and plastic poles placed at different distances from the fire. The purpose was to determine
a critical distance for fire spread between HGV trailers for different heat release rate histories. The time to ignition of
a second object and fire spreading distances were estimated from post-visual observations and temperature measurements. Correlations
for flame length were developed from the experimental results. Since the average temperature of the cross-section often is
used to estimate fire spread, results from a model for the average temperature were compared with the measured temperatures. 相似文献
110.