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111.
112.
甲醛法测定铵盐含氮量 总被引:6,自引:0,他引:6
对甲醛法测定铵盐含氮量进行了研究,提出采用百里酚酞和酚酞混和指示剂进行测定。该法简单、快速、准确,能满足生产实际和样品检验需要。 相似文献
113.
S. Yonemochi A. Sugiyama K. Kawamura T. Nagoya R. Aogaki 《Journal of Applied Electrochemistry》2004,34(12):1279-1285
Novel air purification materials were fabricated by the application of a magnetic field. In a magnetic field perpendicular to a copper plate, nickel particles with a diameter of 10 m were arranged to form numerous pillar-like structures on the matrix surface, and copper as a binder was deposited onto the three-dimensional surface. The total surface area of the pillars and the matrix increased with the magnetic flux density, up to about 800 cm2 per cm2 of the original matrix surface at 6.2 T. After successful codeposition of TiO2 particles on the fabricated materials by electroplating, their photocatalytic activities were evaluated on the basis of the removal efficiency of nitrogen oxides (NO
x
), which are some of the most hazardous air pollutants. It was concluded that the samples with the pillar-like structures had two opposite characteristics: large surface area as a positive effect and shadowing against ultraviolet (UV) irradiation as a negative effect. However, total photocatalytic activity increased to twice as much as that of the flat sample by improving the UV irradiation method and the preparation condition of the materials 相似文献
114.
P. Muthuswamy C. R. Ranganathan V. Murugappan P. Santhy G. Ramanathan 《Nutrient Cycling in Agroecosystems》1990,23(3):135-140
A mathematical model has been proposed for predicting the changes in soil nitrogen status due to continuous fertilization in a continuous cropping sequence. The model also enabled the prediction of the steady state of soil nitrogen for a specified fertilizer practice.The model was applied to six years nitrogen availability data of four fertilizer practices in finger millet-maize-cowpea sequence followed in the Long Term Fertilizer Experiments conducted at Tamil Nadu Agricultural University, Coimbatore, India. The agreement between the predicted soil nitrogen status by the model and the actuals was proved by employing reliability index. 相似文献
115.
Color and COD retention by nanofiltration membranes 总被引:3,自引:0,他引:3
In the present study the application of the nanofiltration process was investigated mainly in the retention ofcolor and chemical oxygen demand (COD) present in textile industry wastewater. Nanofiltration experiments were carried out in a pilot unit, operating in crossflow. Three different types of spiral wound membranes, DK 1073, NF 45 and MPS 31 were used simultaneously in the same unit. The results of the tests showed that for color retention, the values were around 99% for the DK 1073 and NF 45 membranes and the 87% for COD retention for the DK 1073. The permeate flux for the different wastewaters varied from 30.5 to 70 L/h.m2. Fouling was observed in all membranes due to the accumulation of molecular species close to the filtering surface. The process was efficient and promising for the reuse of wastewater from this type of industry. 相似文献
116.
硫酸铜灭藻影响因素的试验研究 总被引:1,自引:0,他引:1
目的通过对硫酸铜灭藻影响因素的试验研究,确定出硫酸铜灭藻的最佳工况条件.方法以叶绿素a法作为检测方法,通过烧杯试验,确定处理含藻水的最佳硫酸铜投加量、接触反应时间、pH等参数.结果硫酸铜最佳投加量为1.5 mg/L;硫酸铜适宜的接触反应时间为8~12 h;pH值6.6左右时,硫酸铜藻类去除率较高,pH值>9时,藻类去除率显著降低.结论 pH值对硫酸铜灭藻效果的影响较大;温度对硫酸铜灭藻有一定的影响;水中还原物质浓度对硫酸铜灭藻影响较小;藻类浓度不同对硫酸铜灭藻效果有一定的影响. 相似文献
117.
118.
论述了肥料中铵态氮、硝态氮、酰胺态氮和有机质氮等各种形态氮的测定意义,系统地介绍了肥料中各种形态氮的测定方法以及应用情况。 相似文献
119.
The new dust removal technical route using the carbon-granular bed filter,packed of carbon particles with appropriate grade derive from an online-process vibration sieve,to replace the traditional baggy filter had been developed successfully for capturing the micro-carbon dusts produced from pulverization of petroleum coke,and the green close loop of carbon materials is thus completed in the combined pulverizing and classifying system and pulverized carbon dust removal process.The high dust removal efficiency greater than 99%,low outlet dust concentration less than 100 mg.m-3,low pressure drop through dust filtration chamber less than 980 Pa,simple and easy design,and flexible and stable operation were achieved also with the carbon-granular bed filter in both bench and industrial scale operations. 相似文献
120.