间歇式高速摄影机的分辨率

文中讨论了间歇式高速摄影机分辨率的计算方法.     

城市污水处理厂曝气池泡沫产生菌的分离与鉴定

通过对曝气池表面泡沫进行涂片染色、显微镜观察、微生物培养及细菌数量测定,确认福建某城市污水处理厂暴发严重的泡沫是由于球杆菌大量繁殖所致.进一步对该菌进行分离纯化和分类鉴定,结果表明泡沫产生菌是乙酸钙不动杆菌(A cinetobacter ca lcoaceticus).     

Exponential synchronization of complex networks with nonidentical time-delayed dynamical nodes

In this Letter, exponential synchronization of a complex network with nonidentical time-delayed dynamical nodes is considered. Two effective control schemes are proposed to drive the network to synchronize globally exponentially onto any smooth goal dynamics. By applying open-loop control to all nodes and adding some intermittent controllers to partial nodes, some simple criteria for exponential synchronization of such network are established. Meanwhile, a pinning scheme deciding which nodes need to be pinned and a simply approximate formula for estimating the least number of pinned nodes are also provided. By introducing impulsive effects to the open-loop controlled network, another synchronization scheme is developed for the network with nonidentical time-delayed dynamical nodes, and an estimate of the upper bound of impulsive intervals ensuring global exponential stability of the synchronization process is also given. Numerical simulations are presented finally to demonstrate the effectiveness of the theoretical results.     

Chaotic synchronization by the intermittent feedback method

This paper studies the synchronization of chaotic systems by the intermittent feedback method which is efficient. A sufficient synchronization criterion for a general intermittent linear state error feedback control is obtained by using a Lyapunov function and differential inequalities. Numerical simulations for the chaotic Chua oscillator are presented to illustrate the theoretical results.     

离子交换法处理曝气后氯化亚铜的废水研究

通过预曝气的方法,氯化亚铜废水溶液中Cu(Ⅰ)被氧化为Cu(Ⅱ),并能简化氯化亚铜废水溶液的粒子结构,分别采用201×7 OH-型强碱性阴离子树脂和732 Na型强酸性阳离子树脂处理曝气后的氯化亚铜废水,进行了曝气时间、pH值和温度等因素对废水处理效果的研究,得到最佳的处理废水条件。曝气180 min后,在温度60 ℃,V溶液/V树脂=2/1,阳离子交换反应15 min时,可使废水溶液中铜粒子浓度达到国家废水一级排放标准。     

曝停组合对ABIR处理城市污水性能的影响

对连续流间歇曝气技术在活性污泥-生物滤池一体化反应器(AB IR)处理城市污水性能进行了研究,考察了在活性污泥段稳定运行条件下,生物滤池段在不同曝气-停曝时间组合下的整个反应器处理城市污水的性能.研究表明,反应器温度为20℃,活性污泥段负荷为0.4 mgCOD/mgMLSS.d,滤池段C/N为1.32、DO控制在1.0 mg/L、曝气-停曝时间为2 h/1 h时,反应器出水COD、SS、NH4+-N以及TN值均能达到《城镇污水处理厂污染物排放标准》(GB18918-2002)一级标准的B标准.     

Intermittent counter-current extraction as an alternative approach to purification of Chinese herbal medicine

This paper describes intermittent counter-current extraction, a novel method of using a conventional twin column counter-current chromatograph to either split a sample into two groups of compounds or extract and enrich a target compound from a crude extract. The first method is demonstrated by splitting a model mixture of four compounds into two groups. The second method is demonstrated by the extraction and enrichment of a high value target compound, triptolide, from a Chinese herbal medicine crude extract of Tripterygium wilfordii Hook. f., where it is found at low concentration (2%). This was achieved by retaining and enriching the target compound within the column while washing away all other components of the crude material. The success of the first method allowed the second method to be carried out without the need for costly preliminary experiments with the high value sample. 188 mg of triptolide at greater than 98% purity was separated from 9.2 g of crude extract, using 10 l of solvent in a 3-h separation.     

Dynamic modelling of an intermittent slider–crank mechanism

This paper investigates kinematic and dynamic analyses of a novel intermittent slider–crank mechanism, which consists of four parts: a crank, a connecting rod associated with a pneumatic cylinder, a slider and two stops at both ends of a stroke. When the crank rotates continuously, the slider will contact with the stops and the pneumatic cylinder is compressed or extended. One periodic motion of the intermittent slider–crank mechanism driven by a permanent magnetic (PM) synchronous servomotor could be divided into three stages. Three governing equations are formulated by Hamilton’s principle. A spring model instead of the pneumatic cylinder is also used for comparison. Finally, the transient amplitudes obtained by using Runge–Kutta method are compared with those of the conventional slider–crank mechanism.     

射流曝气技术在脱硫浆液氧化工艺中的应用

亚硫酸钙的氧化率是衡量高硫煤电厂石灰石/石膏湿法烟气脱硫工艺效率的重要指标.笔者采用集曝气与搅拌为一体的射流曝气技术实现石灰石/石膏湿法脱硫强制氧化以提高氧化率,研究了脱硫浆液射流曝气氧化工作原理.基于ANSYS CFX对脱硫浆液罐的内部流场进行数值模拟实验,确定了浆液混合搅拌效果较为理想的射流曝气器安装方式:将3个射流曝气器垂直于浆液罐壁均布在离浆液罐底部0.8m的平面上;并在重庆某环保公司进行现场应用实验,测定了在此安装方式下射流曝气器的吸气量,并采用碘量法测定了脱硫浆液中亚硫酸钙的氧化率,应用结果表明:射流曝气器吸气量总量为59.52 m3/h,满足浆液氧化需气量要求,且浆液经过射流氧化2h后,亚硫酸钙氧化率达87.6％.     

硝化棉废水处理工艺应用研究

通过混凝+两段活性污泥法对硝化棉废水处理工程运行效果的分析,研究了在不同的温度条件下利用不同的运行方式所产生的运行效果,寻求系统的优化运行方法。结果表明:当水温在18℃以上时,只采用两段生化(低氧-好氧)处理即可使出水CODCr、BOD5、SS等指标达到国家《污水综合排放标准》(8978—1996)二级标准,仅出水色度稍高;而当水温T<18℃时,经过两段生化处理后废水CODCr在300mg/L以上,需要启动物化处理单元,在生化处理前或后增加一级混凝沉淀处理,处理出水均可达到二级标准要求。