应用高效离子交换色谱分析青枯菌的致病力分

应用高效离子交换色谱和激光光散射仪检测器对不同致病力的青枯菌进行分析,建立了一种快速检测青枯菌致病力分化的新方法青枯菌纯培养物经过高效离子交换色谱分离得到3个致病力不同的特征峰,大小依次为峰3组分>峰2组分>峰1组分.对10株青枯菌进行色谱分析,并结合番茄组培苗感染试验检测其致病力,结果发现,强致病力菌株经过色谱分离只在峰3的保留时间位置出现单一特征峰,在9 d内即可引起100%的番茄组培苗发病;若菌株经过色谱分离形成3个特征峰,则峰3所占的面积比越大,该菌株的致病性相对就越强.25株不同致病力青枯菌的验证试验表明了该方法的可行性,番茄组培苗发病率x与峰3面积比y之间呈现出良好的线性关系,回归方程y=0.9581x+5.4984,相关系数r=0.986.通过对青枯菌色谱行为、致病力、细胞表而黏附的EPS Ⅰ含量三者之间相互关系的进一步研究,发现青枯菌的致病力越强,则细胞表面黏附的EPSⅠ越多,峰3所占的面积比就越大.图3表6参15     

壳聚糖负载膨润土处理高浊度废水的效果

以天然膨润土为原料,壳聚糖为改性剂,采用微波改性技术制备了壳聚糖负载膨润土,应用于高浊度废水的处理.通过正交试验确定了废水处理工艺各种影响因素的最佳条件.比较了负载土、原土、壳聚糖的处理效果,结果表明:负载土对高浊度废水的去浊效果明显好于原土、壳聚糖;对于浊度为9250～9480 NTU的废水,经30 min自由沉降后,在投土量为4.0 g·L~(-1)、投土粒度为0.150 mm、搅拌速度为100 r·min~(-1)、搅拌时间为10 min的条件下,废水剩余浊度为6.0～7.0 NTU,浊度去除率高达99.9%.出水水质满足<再生水作循环冷却水水质>的水质要求.     

高压输电杆塔防恐风险评价指标体系

电力防恐是电力安全运营的重要保证。通过风险指数评价方法构建高压输电杆塔遭受恐怖袭击评价的基本层级,以技术接受模型确定防恐风险指标选取原则和特点,结合高压输电杆塔的实际参数,设定单个指标的判断方法并建立高压输电杆塔防恐风险值的算法。实例验证表明,该算法能准确辨识高风险袭击对象,能有效提升高压输电线路防恐能力。     

秦山核电厂换料大修高风险作业控制应用及优化

根据秦山核电厂三十万千瓦机组换料大修高风险作业控制实践经验,介绍一种基于安全许可管理的大修高风险作业控制模式,将高风险作业控制流程嵌入电站生产管理系统,与工单直接关联,实现了高危作业活动识别、风险分析及安全防护措施制定电子流程化。通过对电厂最近六次机组换料大修高风险作业控制相关数据统计、比较,评价高风险作业控制模式在电厂大修中应用效果的稳定性与有效性;根据核电厂大修类作业项目特点,提出机组换料大修期间大纲作业项目高风险作业控制改进方向。     

偏远高山湖泊沉积物中持久性有机污染物的沉积记录研究

持久性有机污染物(POPs)因具有半挥发性,可随大气长距离传输迁移到偏远的高山地区,对当地生态环境造成潜在威胁,因而POPs在这些地区的归趋及行为受到广泛关注.偏远高山地区环境中的POPs主要来源于大气沉降过程,湖芯能较好地保存大气污染物的沉降信息以及年代信息,被称为"天然档案室",常被用于研究污染物的沉降历史和演变规律.本文首先介绍了几种常用于湖芯定年的放射性核素定年方法,然后综述了不同区域高山湖芯中POPs的时空变化趋势以及影响因素,最后针对偏远高山沉积物研究存在的不足对未来研究提出了几点建议.     

Municipal wastewater treatment in China: Development history and future perspectives

The history of China’s municipal wastewater management is revisited. The remaining challenges in wastewater sector in China are identified. New concept municipal wastewater treatment plants are highlighted. An integrated plant of energy, water and fertilizer recovery is envisaged. China has the world’s largest and still growing wastewater sector and water market, thus its future development will have profound influence on the world. The high-speed development of China’s wastewater sector over the past 40 years has forged its global leading treatment capacity and innovation ability. However, many problems were left behind, including underdeveloped sewers and sludge disposal facilities, low sustainability of the treatment processes, questionable wastewater treatment plant (WWTP) effluent discharge standards, and lacking global thinking on harmonious development between wastewater management, human society and the nature. Addressing these challenges calls for fundamental changes in target design, policy and technologies. In this mini-review, we revisit the development history of China’s municipal wastewater management and identify the remaining challenges. Also, we highlight the future needs of sustainable development and exploring China’s own wastewater management path, and outlook the future from several aspects including targets of wastewater management, policies and technologies, especially the new concept WWTP. Furthermore, we envisage the establishment of new-generation WWTPs with the vision of turning WWTP from a site of pollutant removal into a plant of energy, water and fertilizer recovery and an integrated part urban ecology in China.     

油烟净化器的研制

研制的油烟净化器具有设计新、除油率高、组合模块、易安装维护、占地面积小、重量轻等特点,采用单片机控制整机电路,具备多种保护,运行智能化,具有广泛的推广应用价值。     

Metallic wastewater treatment by sulfate reduction using anaerobic rotating biological contactor reactor under high metal loading conditions

An-RBC reactor is highly suited to treat metallic wastewater. Metal removal is due to sulfide precipitation via sulfate reduction by SRB. Cu(II) removal was the best among the different heavy metals. Maximum metal removal is achieved at low metal loading condition. Metal removal matched well with the solubility product values of respective metal sulfide salts. This study was aimed at investigating the performance of anaerobic rotating biological contactor reactor treating synthetic wastewater containing a mixture of heavy metals under sulfate reducing condition. Statistically valid factorial design of experiments was carried out to understand the dynamics of metal removal using this bioreactor system. Copper removal was maximum (>98%), followed by other heavy metals at their respective low inlet concentrations. Metal loading rates less than 3.7 mg/L?h in case of Cu(II); less than 1.69 mg/L?h for Ni(II), Pb(II), Zn(II), Fe(III) and Cd(II) are favorable to the performance of the An-RBC reactor. Removal efficiency of the heavy metals from mixture depended on the metal species and their inlet loading concentrations. Analysis of metal precipitates formed in the sulfidogenic bioreactor by field emission scanning electron microscopy along with energy dispersive X-ray spectroscopy (FESEM-EDX) confirmed metal sulfide precipitation by SRB. All these results clearly revealed that the attached growth biofilm bioreactor is well suited for heavy metal removal from complex mixture.     

HEPA空气净化器对学校室内颗粒物的净化效果研究

为了解HEPA（high efficiency particle air filter,高效空气过滤器）空气净化器在小学教室和寝室的净化效果,于2019年3—4月在北京市一所全寄宿小学开展了一项HEPA空气净化器的交叉干预研究.记录干预组、非干预组室内和室外PM_2.5、PM₁₀、PM₁的浓度,计算空气净化器的净化率;采用多元线性回归模型探索净化效果的影响因素.结果表明:①空气净化器对PM_2.5、PM₁₀、PM₁的净化率分别为41.3%〔Q_l~Q_u（下四分位数~上四分位数,下同）:0~53.1%〕、40.7%（10.5%~46.2%）和34.9%（9.6%~40.3%）,其中对PM_2.5的净化率最高;寝室的净化率高于教室的净化率.②当室外PM_2.5浓度为[115,150）μg/m3时对PM_2.5的净化率最高,为52.83%（50.26%~56.13%）,PM₁₀和PM₁亦有类似结果.③多元线性回归分析表明,室外PM_2.5浓度 < 35 μg/m3时,开门通风和室内人员活动分别使室内PM_2.5浓度下降3.73 μg/m3〔95%置信区间（95% CI）:（0.60 μg/m3,6.86 μg/m3）〕和升高3.4 μg/m3（0.22 μg/m3,6.58 μg/m3）;室外PM_2.5浓度为[35,150）μg/m3时,空气净化器使室内PM_2.5浓度下降33.36 μg/m3（16.47 μg/m3,50.25 μg/m3）;室外PM_2.5浓度≥150 μg/m3时,空气净化器和开门通风分别使室内PM_2.5浓度下降48.87 μg/m3（25.62 μg/m3,72.12 μg/m3）和升高37.65 μg/m3（5.60 μg/m3,69.69 μg/m3）.研究显示:空气净化器可同时降低室内PM_2.5、PM₁₀、PM₁的浓度;当室外PM_2.5浓度 < 35 μg/m3时,不需开启空气净化器;当室外PM_2.5浓度为[35,150）μg/m3时,空气净化器有较好的净化效果,偶尔开窗通风不影响空气净化器的净化效果;当室外PM_2.5浓度≥150 μg/m3时,开启空气净化器时应关闭门窗,以免影响其净化效果.      

新疆且末地区沙尘暴过程中空气细菌群落结构变化的比较

采集新疆且末地区沙尘暴空气微生物样品,揭示沙尘暴前期、中期和后期细菌多样性和群落结构差异,为沙尘暴灾害预警提供依据.采用16S rRNA基因高通量测序技术,研究其菌群组成、丰度、优势菌群及与环境因子的相关性.新疆且末地区沙尘暴空气样品中共获得740364条有效序列,聚类为156个可操作分类单元（Operational Taxononmic Units）,包括9个门,87个属.门水平上,丰度最高为变形菌门（Proteobacteria,80.52%）,其次为拟杆菌门（Bacteroidetes,20.96%）、放线菌门（Actinobacteria,5.84%）和厚壁菌门（Firmicutes,2.63%）;在属水平上,优势属为不动杆菌属（Actinobacteria）、假单胞菌属（Pseuodomonas）、鞘氨醇宝盒菌属（Sphingobacterium）、海洋杆菌属（Ponibacter）.沙尘暴中期空气细菌的Chao 1（135.013）、ACE（130.424）、Shannon（2.614）指数均高于沙尘暴前期和沙尘暴后期空气细菌多样性数值（p<0.01）.沙尘暴空气细菌主成分分析表明,不同时期的细菌群落组成差异显著.冗余分析表明,湿度和气压可能与沙尘暴空气细菌多样性呈正相关,与经度、维度、海拔和温度呈负相关.新疆且末地区沙尘暴中蕴藏着丰富的细菌资源,沙尘暴前中后期空气微生物菌落结构和物种多样性差异显著.