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991.
利用湿式静电除尘器(ESP)脱除汞 总被引:2,自引:0,他引:2
燃烧高硫煤或低硫煤电厂应认真考虑的一种汞排放控制方式是采用湿式电除尘器脱除烟气中的汞。烟气中的汞如果以水溶性的氧化物形式存在就可以直接以颗粒物形式脱除,而如果以元素汞形式存在可以被吸附剂吸附后再被间接脱除。已经证实湿式电除尘器可去除燃中、高硫煤锅炉产生的亚微米级的颗粒物和酸雾排放。现在来看,如果在ESP(静电除尘器)之后布置湿式电除尘器(WESP)代替布袋除尘器,则对燃低硫份的次烟煤或褐煤锅炉可能会得到相同的汞排放控制效果。 相似文献
992.
M. V. Peralta-Martinez M. J. Assael M. J. Dix L. Karagiannidis W. A. Wakeham 《International Journal of Thermophysics》2006,27(3):681-698
New measurements of the thermal conductivity of molten mercury, gallium, tin, and indium are reported up to 750 K. The measurements are performed in a novel transient hot-wire instrument described elsewhere. The present experimental technique overcomes problems of convection, and it is shown that it operates in an absolute way in accord with a theoretical model. The uncertainty of the thermal conductivity results is estimated to be ± 2%, which is superior to that achieved in most earlier work. The low uncertainty of the present experimental results has allowed us to test the only significant theory for the thermal conductivity of molten metals, which relates this property to the electrical conductivity. The pattern of results among the four metals indicates that further theoretical developments would be warranted. 相似文献
993.
The poly (methyl methacrylate) (PMMA)/single-walled carbon nanotube (SWNT) composites with good uniformity, dispersion and
alignment of SWNT were fabricated in an improved figuration process. The semidried mixture was stretched along one direction
at a drawing ratio of 50 before it was dried, and then folded along the same direction stretching repeatedly for 100 times.
The transmission electron microscopic (TEM) observation demonstrated that SWNT in the PMMA/SWNT composite tends to align in
the stretching direction owing to a torque exerting on it in the stretching process. The electrical and mechanical properties
of PMMA/SWNT composite were studied as a function of SWNT orientation and concentration. The aligned SWNT modified PMMA/SWNT
composite presented highly anisotropic properties. The experimental results showed that the electrical conductivity and mechanical
properties of composite rise with the increase of SWNT concentration, and that composite films showed higher conductivity
and higher mechanical draw ratios along the stretched direction than perpendicular to it. The thermogravimetric analysis (TGA)
revealed that embedding the SWNTs into the PMMA matrix also improves the thermal stability of the composite. 相似文献
994.
The geological repository of nuclear waste in concrete containers is a possible storage method explored by ANDRA (Agence Nationale
pour la gestion des Déchets RadioActifs).
The concrete must display a high confinement capacity for long periods, characterized by low transport properties and by the
acido-basic buffer of hydrated cement. During service life, these properties can be endangered by chemical attack of underground
water.
The cement type has an important influence on the concrete's performances. Then, it is essential to establish appropriate
mixtures with accurate components.
In this work an ordinary Portland cement and a fly ash and blast furnace slag blended cement are compared.
To determine confinement capacities, transfer properties and mortars microstructure were investigated.
To predict the long term behaviour, an ammonium nitrate test has been developed to enhance decalcification and to accelerate
hydrolysis of cementitious materials.
Measurement of degraded depth with time regarding calcium content was carried out. Impact of decalcification on transport
properties was evaluated.
Fly ash and blast furnace slag provide better properties for native mortars, and more particularly diffusion properties, but
not as much as necessary to limit leaching in degraded material by chemical attack. 相似文献
995.
在Triton X-100存在下的pH 10的Na2B4O7-NaOH缓冲介质中,研究了1-吡淀-3-[4-(苯基偶氮)苯基]-三氮烯(PYPAPT)与汞离子(Hg2 )的显色反应,建立了微量汞的测定方法。Hg2 与PYPAPT形成1∶2的红色络合物,络合物最大吸收波长位于518 nm,表观摩尔吸光系数为1.42×105L.mol-1.cm-1,Hg2 质量浓度在0~0.64 mg/L范围内符合比尔定律。方法用于铅锌矿样中微量汞的测定,RSD小于2.6%,测定结果与AAS法相符。 相似文献
996.
997.
本文以实验数据为基础,探讨了大气中二氧化硫监测方法——甲醛法在烟气二氧化硫测试中应用的可能性,以期为烟气二氧化硫的测试提供一种更为快捷简便的方法。 相似文献
998.
讨论了温度、物料配比及压力对原甲酸三甲酯收率的影响,找出了最佳反应条件。 相似文献
999.
采用紫外可见光谱研究了甲基绿与多壁碳纳米这水溶胶之间的相互作用,并近似计算出结合常数,实验结果表明静电力和疏水作用是两者结合的主要驱动力。 相似文献
1000.
Yuji Takeda Masami Takagi Takayoshi Kurita Yoji Watanabe Mamoru Amano Hiroki Nakano 《Journal of the Society for Information Display》2003,11(4):667-673
Abstract— A reliable external‐electrode mercury fluorescent lamp (EEFL) has been developed for backlighting a liquid‐crystal‐television (LC‐TV) display. This involved the investigation of the EEFL characteristics and the improvement in the construction of the EEFL and drive waveforms, in the frequency range of 50–200 kHz, that affects the EEFL characteristics. The results showed that a sinusoidal waveform is suitable for driving the EEFL, and EEFL's voltage decreases when the frequency of the drive waveform is increased. 相似文献