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41.
用环形扩散管和滤纸联用采样技术采集空气中氨和铵盐 总被引:1,自引:0,他引:1
建立了环形扩散管和滤纸采样夹联用,分形态同时采集空气中所态氨和颗粒态铵盐的方法。在同一气流中,采用涂渍1.5%草酸乙醇水溶液的环形扩散管采集气态氨,用浸渍上述试剂的玻璃纤维纸和慢速定量滤纸分别采集颗粒安和第一层滤纸上的铵盐挥发产生的氨气。用靛酚蓝比色法分别测定氨和铵盐。当采气流速为1.0L/min时,采样效率高于98.2%。将本法测得的氨气和铵盐的总量与标准采样方法的测定结果比较。无显著性差异(P 相似文献
42.
Preparation and Characterization of Nanotitanium Dioxide Coating Film Doped with Fe^3+ Ions on Porous Ceramic 总被引:2,自引:0,他引:2
The nanotitanium dioxide (TiO2) photocatalytic and porous ceramic filtering technique is one of the advanced methods to effectively treat organic wastewater. The TiO2 sol doped with Fe^3+ ions was prepared by sol-gel processing. The influences of the process conditions of coating nanophotocatalytic material- Fe^3+-TiO2 film on the surface of porous ceramic filter by dipping-lift method on the performance of porous ceramic filter were studied. The porous ceramic filters have two functions at the same time, filtration and photocatalytic degradation. The results of this study showed that the pH and viscosity of the sol, amount of Fe^3+ ions doped as well as the coating times greatly affect the quality of coating film, the performance parameters and the photocatalytic activity of the porous ceramic filter. When the pH of the sol is 3-4, the viscosity is about 6 mPa.S, the amount of doped Fe^3+ ions is about 2.0 g/L, the porous ceramic filter has been shown to have the best filtering performance and photocatalytic activity. In this condition, the porosity of porous ceramic is about 42.5%, the pore diameter is 8-10μm. The degradation of methyl-orange is 74.76% under lighting for 120 rain. 相似文献
43.
改进的单纯形优化法用于混合稀土的同时测定 总被引:1,自引:0,他引:1
本文应用改进的单纯形优化法较好地弥补了目前在分析化学计量学中得到广泛应用的卡尔曼滤波法所存在的不足,交法应用于混合稀土的同时测定中,获得了满意的结果,结果准确度较卡尔滤波法的有显著的提高。 相似文献
44.
A microwave-assisted digestion procedure using HNO3, HF, and H2O2 has been developed for analysis of elements in ambient particulate matter (PM). The samples are collected on cellulose filters and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The ICP-MS is calibrated with external standards, and recovery of analytes is tested with NIST SRM 1648 Urban Dust. This method has been used to quantify the airborne concentrations of a large number of elements, including Ag, As, Ba, Be, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, K, Li, Mg, Mn, Mo, Ni, Pb, Rb, Se, Sb, Sr, Ti, Tl, V, and Zn. For the majority of these elements, recovery of the NIST SRM is within 15% of the certified values. 相似文献
45.
Efforts were made to assess the efficiency of an anaerobic filter packed with porous floating ceramic media and to identify
the optimum operational condition of anaerobic filter as a pretreatment of swine wastewater for the subsequent biological
removal of nitrogen and phosphorus. A stepwise decrease in hydraulic retention time (HRT) and an increase in organic loading
rate (OLR) were utilized in an anaerobic filter reactor at mesophilic temperature (35°C). The optimum operating condition
of the anaerobic filter was found to be at an HRT of 1 d. A soluble chemical oxygen demand (COD) removal efficiency of 62%
and a total suspended solids removal efficiency of 39% at an HRT of 1 d were achieved with an OLR of 16.0 kg total COD/(m3·d), respectively. The maximum methane production rate approached 1.70 vol of biogas produced per volume of reactor per day
at an HRT of 1 d. It was likely that the effluent COD/total Kjeldahl nitrogen ratio, of 22, the COD/total phosphorous ratio
of 47, and the high effluent alkalinity >2500 mg/L as CaCO3 of the anaerobic filter operated at an HRT of 1 d was adequate for the subsequent biological removal of nitrogen and phosphorus. 相似文献
46.
Min-zhi Chen Xiao-liang Wang Fang-fang Tao Qi Xue Ping-chuan 《高分子科学》2007,(1):107-111
The concept of entanglement provides the basis of our current understanding of the flow behavior of polymer melts, Current techniques developed to investigate the degree of interpenetration of polymer chains only provide indirectly the information of the degree of entanglement in a relatively large scale (several to tens of nanometer). In this article, we report ^1H-NMR spectroscopy with dipolar filters under fast magic angle spinning for probing chain interpenetration of polymer glasses at the molecular level. 相似文献
47.
Summary A simple optimization method based on the well-known Rs-minimum method and on the information theory of FUMI Φ is proposed.
Resolution (Rs), peak area and height (or width) are the only parameters necessary for the calculation of the information
Φ and information flow ϑ. The most precise analysis can be selected as the chromatogram having maximal ϑ. Mobile phase composition,
column length, flow rate, detection wavelength, amount of internal standard, etc. can be optimized by this method. 相似文献
48.
The adsorption of a surfactant mixture, based on an anionic surfactant, sodium dodecyl benzenesulfonate (SDBS) and a nonionic
surfactant (Triton X-100, or TX100), on alumina nanoparticles was determined by solution depletion method combined with spectrometric
measurement. It is shown that the light scattering, originated from the residual adsorbent alumina particles in the supernatant
after centrifugation separation, interferes with the measurements of absorbance of the surfactant molecules, and therefore
constitutes an error source for determination of the surfactant concentration in the supernatant by spectrometric means. The
intensity of this light scattering, namely the influence of the residual alumina nanoparticles upon the surfactant adsorption,
was related to the surfactant adsorption and its equilibrium concentration and varied among a batch. In this paper we report
a Kalman filter method in order to eliminate the variational scattering background caused by non-separated residual alumina
nanoparticles in each supernatant. This method is of interest as it is simple, easy to carry out and of high precision. 相似文献
49.
The fast trace analysis method used to monitor 2,3,7,8-TCDD in stack gas during the incineration of the waste from Seveso is described. The sampling of volatile organic compounds from flue gases, distributed between all three aggregation states, is based on a micromethod developed for the trace analysis of water using a specially dimensioned adsorptive charcoal filter (1.5 mg charcoal). In conjunction with subsequent GC/MS measurements the rapid “fast cycle trace analysis” ensured specific 2,3,7,8-TCDD detection down to 100 pg per m3 flue gas in cycle times of about 1–2 hours. 相似文献
50.
针对捷联制导系统的自身特点,设计出用于估计导弹和目标在弹体坐标系中相对运动状态的卡尔曼滤波器,使滤波与制导在同一个坐标系即弹体坐标系内进行,避免了信息在弹体坐标系和惯性坐标系之间的多次转换,从而减少了信息损失.仿真结果表明,该方法能够满足捷联制导系统的要求. 相似文献