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排序方式: 共有1307条查询结果,搜索用时 15 毫秒
921.
Tomoyuki Imai Toshiki Matsui Yasuhiko Fujii Tasuku Nakai Suminori Tanaka 《Journal of Material Cycles and Waste Management》2001,3(2):103-109
A new iron oxide catalyst, which has a superior oxidation activity in carbon monoxide and polyethylene (PE) combustion, was
synthesized by an aqueous solution reaction. Catalytic oxidation of carbon monoxide over six kinds of hematite obtained from
the goethite was done using a microcatalytic pulse reactor, and the composition of the hematite with the highest oxidation
activity was determined. With the aim of suppressing dioxin formation on combustion, incineration tests of solid wastes in
PE refuse bags with and without the goethite were carried out using a commercial semibatch-type incinerator with a combustion
chamber of 6.2 m3. The result confirmed that the concentration of dioxins in the flue gas decreased considerably when the refuse was incinerated
in PE bags manufactured with goethite.
Received: July 24, 2000 / Accepted: October 18, 2000 相似文献
922.
923.
沉积物和土壤中磷的生物有效性评估新方法 总被引:16,自引:4,他引:12
利用自制的氧化铁/醋酸纤维素复合膜(FeO/CAM)发展了一种沉积物和土壤磷的生物有效性评估的新方法. 结果表明:从沉积物和土壤中解吸的生物有效磷(FeO-P)含量随时间增加而增加,至16~20h左右,解吸过程接近平衡;随着土/水比增大而减小,至20~30g/L左右逐渐趋于平缓,且相对标准偏差较小;膜面积为20~30cm2时FeO-P含量差别较小,且相对标准偏差也较小;适当提高振荡频率(一般200r/min左右),有利于促进FeO-P的提取动力学过程.在用于评估水体沉积物和土壤解吸磷的生物有效性方面,FeO/CAM膜克服了氧化铁浸渍滤纸的缺点,易于商品化,具有更好的应用前景. 相似文献
924.
Photocatalytic degradation of Acid Blue 62 over CuO-SnO2 nanocomposite
photocatalyst under simulated sunlight 总被引:2,自引:0,他引:2
The novel CuO-SnO2 nanocomposite oxide photocatalysts were prepared by simple co-precipitation method, and characterized by X- ray diffraction, transmission electron microscopy, N2 adsorption-desorption measurement and UV-Vis diffuse reflectance spectroscopy. The photocatalytic activities of CuO-SnO2, evaluated using the photodegradation of Acid Blue 62 as a probe reaction under the irradiation of Xenon light, were also found to be related to the calcination temperature and the molar ratio of Cu to Sn. The maximum photocatalytic activity of the CuO-SnO2 photocatalyst was observed to be calcined at 500~C for 3 h (the molar ratio of Cu to Sn was 1:1) due to the sample with good crystallization and high surface area. It also showed much higher photocatalytic activity in treatment dye wastewater under simulated sunlight irradiation compared to Degussa P25 TiO2. 相似文献
925.
长江溶存氧化亚氮的分布与释放 总被引:5,自引:2,他引:5
于2008年1月对长江宜昌到徐六泾段干流以及部分湖泊和支流入江口进行了调查,并于2007年6月到2008年5月对长江徐六泾进行了逐月调查,采样测定了长江溶存N2O的浓度并选择合适的模型估算了其释放通量.结果表明,2008年1月长江表层河水中N2O的平均浓度为(22.0±3.5)nmo·lL-1,均处于过饱和状态,平均饱和度为180%±33%,长江向大气释放N2O通量平均为(13.7±14.6)μmol·m-·2d-1.冬季长江溶存N2O的分布规律为下游溶存N2O浓度高于中游,支流及湖泊高于干流.长江徐六泾段河水中N2O全年平均浓度为(19.4±7.3)nmol·L-1,呈现明显季节变化特征.长江徐六泾段河水中N2O平均释放通量为(43.9±24.9)μmol·m-2·d-1,夏季最高可达80.7μmol·m-·2d-1.初步估算出长江每年向大气释放N2O-N的量为12.0Gg·a-1,约占整个中国N2O排放量的1.1%.而长江输入东、黄海N2O-N的年通量为0.5Gg·a-1,对长江口及其邻近海域N2O分布及氮的生物地球化学循环有重要影响. 相似文献
926.
A series of copper-cobalt oxides supported on nano-titanium dioxide were prepared for the reduction of nitric oxide with carbon
monoxide and characterized using techniques such as XRD, BET and TPR. Catalyst CuCoOx/TiO2 with Cu/Co molar ratio of 1/2, Cu-
Co total loading of 30% at the calcination temperature of 350°C formed CuCo2O4 spinel and had the highest activity. NO conversion
reached 98.9% at 200°C. Mechanism of the reduction was also investigated, N2O was mainly yielded below 100°C, while N2 was
produced instead at higher temperature. O2 was supposed to accelerate the reaction between NOx and CO for its oxidation of NO to
give more easily reduced NO2, but the oxidation of CO by O2 to CO2 decreased the speed of the reaction greatly. Either SO2 or H2O
had no adverse impact on the activity of NO reduction; however, in the presence of both SO2 and H2O, the catalyst deactivated quickly. 相似文献
927.
采用介质阻挡放电低温氧等离子体技术进行表面改性的活性碳纤维(ACFP)为载体,进行CeO2/ACFP催化剂低温选择性催化还原(SCR)NO的研究。实验结果表明,ACF先经过低温氧等离子体技术进行表面改性后再负载CeO2,能明显提高对NO的去除率。在NO体积分数为1×10^-3、NH3体积分数为2×10^-3、O2体积分数为5%、Ar作为平衡气、反应温度为120—240℃的条件下,较理想的CeO2负载量(质量分数)为9%;在180℃用9%CeO2/ACFP为催化剂时,NO去除率为86.01%。 相似文献
928.
Lenwood W. Hall Jr. Alfred E. Pinkney Scott Zeger Dennis T. Burton Michael J. Lenkevich 《Journal of the American Water Resources Association》1984,20(2):235-239
ABSTRACT: The objective of this investigation was to evaluate the avoidance responses of juvenile striped bass, Morone saxatilis and Atlantic menhaden, Brevoortia tyrannus to bis (tri-n-butyltin) oxide. An avoidance responses was exhibited by striped bass at a total organic tin concentration of 24.9 μg/L. Atlantic menhaden exhibited avoidance to total organic tin concentrations of 5.5 μg/L and greater. Atlantic menhaden are generally more sensitive to toxicants than striped bass; therefore, avoidance responses reported in this study are not surprising. It is highly likely that the concentrations of total organic tin that were avoided by the test species in this study were much higher than expected environmental concentrations. Ecologically significant hazards may occur due to potential effects that unperceived or non-avoided organotin concentrations may have on behavioral responses mediated by chemosensory systems. 相似文献
929.
The results of a field survey and laboratory study indicated that nitrogenous landfill leachate treatment can be a significant potential source of N2O emission. Nil (raw leachate) to 58.8ngmL(-1)h(-1) (sequential batch reactor) N2O emission was detected at five treatment plants in South China. The production and emission of N2O was especially high soon after the raw leachate was aerated. The emission was positively correlated with the dissolved N2O content in leachate; detected dissolved N2O ranged from 0 to 1309ngmL(-1). All leachate treatment plants studied were effective in NH4+-N removal (>95%); however, the highest N2O emission was estimated to be 0.25g N2Ocapita(-l)year(-1), comparable with the rate of N2O emission in conventional sewage treatment process. 相似文献
930.
Solid fuels in chemical-looping combustion 总被引:1,自引:0,他引:1
Henrik Leion Tobias Mattisson Anders Lyngfelt 《International Journal of Greenhouse Gas Control》2008,2(2):180-193
The feasibility of using a number of different solid fuels in chemical-looping combustion (CLC) has been investigated. A laboratory fluidized bed reactor system for solid fuel, simulating a chemical-looping combustion system by exposing the sample to alternating reducing and oxidizing conditions, was used. In each reducing phase 0.2 g of fuel in the size range 180–250 μm was added to the reactor containing 40 g oxygen carrier of size 125–180 μm. Two different oxygen carriers were tested, a synthetic particle of 60% active material of Fe2O3 and 40% MgAl2O4 and a particle consisting of the natural mineral ilmenite. Effect of steam content in the fluidizing gas of the reactor was investigated as well as effect of temperature. A number of experiments were also made to investigate the rate of conversion of the different fuels in a CLC system. A high dependency on steam content in the fluidizing gas as well as temperature was shown. The fraction of volatiles in the fuel was also found to be important. Furthermore the presence of an oxygen carrier was shown to enhance the conversion rate of the intermediate gasification reaction. At 950 °C and with 50% steam the time needed to achieve 95% conversion of fuel particles with a diameter of 0.125–0.18 mm ranged between 4 and 15 min depending on the fuel, while 80% conversion was reached within 2–10 min. In almost all cases the synthetic Fe2O3 particle with 40% MgAl2O4 and the mineral ilmenite showed similar results with the different fuels. 相似文献