Preparation of biological aerated filter media with coal fly ash and coal gangues

A novel kind of filter media has been studied using in biological aerated filter process which is produced by waste coal fly ash and coal gangues.The specific surface area and sum of braking and ware rate are viewed as the main factor for determining preparation conditions,including calcination temperature (in the range of 900 ℃ to 1250 ℃),proportion of coal gangue (in the range of 0 to 25%) and soaking time (in the range of 0 to 40 min).The effects of sintering conditions on the main property parameters are researched and the reasons have been analyzed.Considered with all factors,the optimum technological conditions are chosen as follows:the calcination temperature is 1050 ℃ ;the soaking time is 10 min and the proportion of coal gangue is 5%.When at these condition,the main property parameters of the filter media in the technological conditions are 1.6 m 2 /g for the specific surface area and 2.96 % for sum of braking and are rate respectively.Finally,a scanning electron microscope is used for analyzing the microstructure of the filter media.     

建筑比例的数学分析

本文分析了常见建筑比例关系.并对几种常见比例进行了比较,指出“抽象“和“移情“作为两种对待自然的态度是如何影响建筑比例的信念的.     

Total dose radiation effects of hybrid bulk/SOI CMOS active pixel with buried channel SOI source follower

A CMOS active pixel with pinned photodiode which used in-pixel buried-channel (BC) transistor has been reported, and the characteristic of CMOS image sensor with in-pixel buried-channel transistor was carried out. In this paper, we have a research on a hybrid bulk/silicon-on-insulator (SOI) CMOS active pixel with pinned photodiode which use buried channel SOI NMOS Source Flower (SF) by simulation. We study the basic characteristics of buried-channel SOI NMOS and the characteristics of CMOS active pixel optimized by using in-pixel buried-channel SOI transistor under radiation. The results show that, compared to the conventional active pixel with the standard surface-channel (SC) SOI NMOS SF, the dark random noise of the pixel which uses in-pixel buried channel SOI NMOS SF can be reduced under the radiation and the output swing is improved.     

Nitrogen removal from municipal wastewater by limit-oxic/anoxic/oxic biological aerated filter system

In this study,a three-stage biological aerated filter(BAF) system was proposed for the enhancement of nitrogen removal in the treatment of low carbon-to-nitrogen ratio(C/N ratio) municipal wastewater.Operational parameters were studied for each process for maximum nitrite accumulation in the nitrification step and nitrite adaptation in the denitrification step.Nitrite accumulation during nitrification could be controlled by the dissolved oxygen(DO) concentration,presenting a mean value of 40% at around 1.0 mg DO/L.Denitrification could be adapted to nitrite and the process was stable if nitrite in the reactor was keep low.Once the operational parameters were established,the process was stable and a steady state was maintained for over 30 days,and the various indexes of discharged water were up to the Discharge standard of pollutants for municipal wastewater treatment plant(GB18918-2002) Level-one A.It was concluded that the three-stage BAF system proposed in this study was excellent in nitrogen removal performance by employing three-column functioning as short-cut nitrification,short-cut denitrification and secondary nitrification,respectively.     

Sorption of endrin to montmorillonite and kaolinite clays

It has been discovered previously that clay minerals may have a greater potential for sorption of pesticides. In this paper, the sorption of endrin, a nonionic persistent organochlorine pesticide, to montmorillonite and kaolinite was investigated. The effect of pH, ionic strength on the sorption was studied. The effect of intercalation of hydroxyl aluminium species on sorption of endrin to montmorillonite was also investigated. The results show that, the sorption isotherm of endrin to montmorillonite and kaolinite was linear. The sorption increases with the increase in ionic strength. pH has effect on the sorption and the sorption on both montmorillonite and kaolinite has obvious troughs at pH about 7.2 and 5.4, respectively. The intercalation of hydroxyl aluminium species decreases the sorption. Sorption mechanism of endrin to montmorillonite and kaolinite was suggested to be a combination of hydrophobic interaction and charge–dipole interaction and troughs in the effect of pH on sorption was attributed to the proton shift reaction of the broken bonds at the clay edges.     

Powerbuilder中报表打印的智能处理方法

从传统手工输出报表的问题出发，介绍了在PowerBuilder中使用数据窗口进行报表打印输出的特点与方法，然后就如何通过编写程序对报表的智能化处理进行了较为详细的讨论。     

A novel way of understanding for calibrating stereo vision sensor constructed by a single camera and mirrors

As a kind of binocular stereo vision system, stereo vision sensor constructed by a single camera and mirrors (SSCMs) has been paid increasing attention for three-dimensional measurement applications due to its low cost, high efficiency and synchronization. Currently, the existing model for SSCM considers the real camera as two half-Field-of-View (FOV) virtual cameras formed by reflection effects of the mirrors. The calibration methods based on this conventional model are either complicated to operate or deriving non-identical system parameters. To solve the problem, a novel model and the corresponding calibration approach are presented, which take the sensor as an integrated structure with the viewpoint that the camera captures two virtual points formed by the same object point due to the reflection effects of the mirrors. Also, the calibration and the measurement accuracy evaluation functions are discussed. Both simulated and real experiments compare the calibration and the measurement error of the proposed method with the two traditional methods. The results show that the proposed approach has higher measurement accuracy and more robust than the traditional methods, which meet high-precision requirements for low-cost three-dimensional measurement applications.     

Topic correlation and individual influence analysis in online forums

Over the last few years, online forums have gained massive popularity and have become one of the most influential web social media in our times. The forum document corpus can be seemed to be composed of various topics evolved over time, and every topics is reflected on a volume of keywords and social actors. In this paper, we attempt to study the interesting problem: for the evolving topics, were there any correlation between them? We propose a method for discovering the dependency relationship between the topics of documents in adjacent time stamps based on the knowledge of content semantic similarity and social interactions of authors and repliers. We introduce mutual information measure to estimate the correlation between the topics. Applied to the realistic forum data, we show how topics are related and which postings can be recommended to another as similar topics. We also show how the authors impact the topics and propose a new way for evaluating author impact.     

全位置管焊机控制系统的研制

采用ＰＣ机对全位置管焊机进行控制,从而实现了焊接过程的实时控制,保证了焊接电流的反馈调节及电弧电压的自动调节。并能够实现焊接小车机头的横向摆动及焊接参数的顺序调整。经过实验验证,焊接过程稳定、焊缝质量较好,具有一定的实用价值。