UASB+A/O处理甜菜制糖废水工程实例

介绍采用UASB+ A/O工艺处理甜菜制糖废水的工程实例.实际运行结果表明,系统运行稳定,处理出水COD≤81 mg/L,BOD≤13 mg/L,SS≤41 mg/L,NH3-N≤7.5 mg/L,处理出水达到《制糖工业水污染物排放标准》(GB2190-2008).工程运行费用低,环境效益和社会效益明显.     

倒计时信号灯绿灯间隔时间设置研究

就保障倒计时信号交叉口交通安全而言,适当设置倒计时信号灯绿灯间隔时间具有重要意义。选择南京一个道路交叉口,利用交通冲突理论,分析产生严重交通冲突的条件,考虑车流不饱和与饱和2种情况,得到在不发生严重交通冲突条件下的绿灯间隔时间,并通过实例说明。研究结果显示,在车流饱和状态下,头车与尾车均为大车时,头车以初速度零开始加速进入交叉口时绿灯间隔时间应最短;在不饱和状态下,头车与尾车均为大车时,头车以一定速度通过交叉口时绿灯间隔时间应最长;车流饱和时绿灯间隔时间应较短,车流不饱和时绿灯设置间隔时间应较长。     

环洞庭湖经济圈旅游产业协同发展探析

环洞庭湖经济圈的可持续发展问题正引起国家相关部门的高度重视,而环洞庭湖经济圈旅游产业的协同发展是实现该区域可持续发展的重要途径。从协同学理论视角出发,阐析区域旅游产业协同发展的理论机理,解析环洞庭湖经济圈旅游产业协同发展的现实基础与主要障碍,提出推进环洞庭湖经济圈旅游产业协同发展的政策建议。     

1种抑制巷道信号NLOS的矿井RSSI高精度定位算法*

在RSSI（Received Signal Strength Indication）测距定位技术中,为抑制巷道信号NLOS（Non Line of Sight）传输对定位结果的影响,提出信号指纹定位和几何优化算法。在离线阶段利用高斯滤波最大值加权法和最小二乘法建立符合矿井巷道环境的无线信号测距模型,设计改进卡尔曼滤波器平滑处理离线信号值,抑制巷道信号NLOS传输带来的影响,建立离线信号指纹库;在线定位阶段,利用加权K最近邻法（WKNN）将定位目标接收到的信号值与指纹库中的信号值进行匹配,将匹配到的最优信号值参与测距定位计算,最后通过几何优化算法将定位结果归一化处理,使其符合一维定位分布。结果表明:所提算法的平均定位误差为0.9 m,相比于高斯滤波最大值加权法、经典卡尔曼滤波指纹定位算法和改进卡尔曼滤波指纹定位方法,其平均误差分别减小2.36,1.17,0.35 m。所提算法能够有效抑制巷道信号NLOS传输对RSSI测距定位的影响,可实现RSSI方法在矿井NLOS环境中的有效应用。     

监控完全遮挡场景下火焰特征分析方法*

为解决监控完全遮挡场景下火灾原因认定面临的问题,探究火焰的视频特征分析方法。利用油盘火、垃圾桶火焰和短路火花3种实体火焰模拟室内火灾,布置普通彩色CCD监控摄像头使之被完全遮挡,收集火灾视频进行预处理,利用视频分析技术提取、对比、分析油盘火焰、垃圾桶火焰和短路火花的HSV颜色、火焰面积增长、质心变化、Harris角点变化、火焰频闪等特征,并总结对应特征变化规律。结果表明:在监控完全遮挡场景下,提出的火焰视频特征分析方法可以较为精确地定量表征火焰动静态特征,为火灾调查工作的顺利开展提供有力的工具。     

基于SEIMR的矿工不安全行为传播模型研究

为防控矿工不安全行为的传播,减少煤矿安全事故的发生,采用传播动力学方法,在传染病模型的基础上提出并构建了易染-潜伏-传播-管控-免疫(SEIMR)传播模型,借助MATLAB软件演化不同状态下矿工人群之间的动态转化关系,模拟转化率对矿工不安全行为传播过程的影响.结果表明,SEIMR模型能够较好地反映矿工不安全行为的传播过程,恶化率、改善率、醒悟率及遗忘率等因素对矿工不安全行为传播有不同程度的影响,提高改善率和醒悟率可以抑制不安全行为的传播,提高恶化率和遗忘率可以促进不安全行为的传播.因此,在煤矿企业安全管理中,可通过调节控制这些因素来预测和干预不安全行为的传播.     

Relation of hepatic EROD activity and cytochrome P4501A level in Sebastiscus marmoratus exposed to benzo[a]pyrene

This study was designed to investigate the in vivo effects of benzo[a]pyrene （BaP） on hepatic ethoxyresorufin-O-deethylase （EROD） activity and its correlation with cytochrome P4501A （CYP1A） protein levels in Sebastiscus marmoratus, which were exposed through a water column to BaP （10, 100, 1000 ng/L, respectively） or were treated with intraperitoneal injections of BaP （0.5, 1, 5, 10 mg/kg, respectively） every 7 d. The results showed that after 25 d of waterborne exposure to 1000 ng/L BaP, fish hepatic CYP1A levels and EROD activity were significantly induced. In contrast, EROD activity was not altered 7 d after second intraperitoneal injections, whereas, CYP1A protein levels were increased. Dose-dependent increase of biliary BaP metabolites demonstrated that the catalytic activity of CYP1A was induced by treatment with BaP. The lowest observable effect concentration with regard to biliary BaP metabolites （100 ng/L） was much lower than that with reference to EROD activity （1000 ng/L）. The results suggest that biliary polycyclic aromatic hydrocarbon （PAH） metabolites were shown to better reflect the contamination gradients of PAHs than EROD activity. It appeared to be necessary to measure CYP1A protein levels to complement the EROD activity in relevant toxicological assessments.     

Decomposition of hexachlorobenzene over Al2O3 supported metal oxide catalysts

Decomposition of hexachlorobenzene(HCB)was investigated over several metal oxides(i.e.,MgO,CaO,BaO,La2O3,CeO2,MnO2, Fe2O3,and Co3O4)supported on Al2O3,which was achieved in closed system at a temperature of 300°C.Catalysts were prepared by incipient wetness impregnation with different metal oxides loading and impregnating solvents.The decomposition effciency of different catalysts for this reaction depends on the nature of the metal oxide used,and Al2O3 supported La2O3 was found to be the most active one.Pe...     

Toxic effects of fluoranthene and copper on marine diatom Phaeodactylum tricornutum

To investigate the effects of polycyclic aromatic hydrocarbons (PAHs) and metals on the population reproduction,antioxidative defense system and cell ultrastructure of the marine diatom,fluoranthene and Cu2+ were selected to test their toxicity to Phaeodactylum tricorntum,in the laboratory.The results indicated that both fluoranthene and Cu2+ inhibited population reproduction of P.tricorntum.When the algal cells were exposed to fluoranthene or Cu2+ for 72 h,ultrastructure damage in the cells was observed un...     

城市高污染燃料禁燃区规划方法及案例研究

在总结高污染燃料禁燃区实际规划过程中的经验、参考已有的大气污染控制规划方法的基础上,针对目前高污染燃料禁燃区规划实践中的不足,将情景分析法、模型分析法以及地理信息系统技术(GIS)应用于规划中,提出并发展了一套解决城市或地区高污染燃料禁燃区规划的整体技术方案,并通过该方法体系在珠海市高污染燃料禁燃区规划中的实际案例分析,显示了该方法的可行性与可操作性,为全国其他城市的高污染燃料禁燃区的合理规划提供了一个实例和参考。