光合细菌PSB07-15对辣椒及土壤中甲氰菊酯残留的生物修复

利用光合细菌菌株PSB07-15对辣椒促生作用及对植株与土壤中甲氰菊酯残留的生物修复进行了研究,为光合细菌生物修复菊酯类农药残留的实际应用提供科学依据。结果表明：菌株PSB07-15菌液用ddH2O稀释100倍液、200倍液浸种处理后能够显著提高辣椒种子发芽率;田间小区试验结果表明,菌株PSB07-15施用1 875、3 750、7 500 mL.hm-2,辣椒鲜质量分别增加15.12%、21.68%、14.79%;菌株PSB07-15能够有效降解辣椒和土壤中甲氰菊酯残留（辣椒中大于47.20%,土壤中大于50.73%）。     

辽河流域高氟地区氟对人体健康的影响

研究了辽河流域高氟地区土壤、作物、饮用水中氟含量,并应用目前美国环保局推荐的健康风险评价模型对辽河流域高氟地区饮用水中氟所引起的健康风险进行初步评价。研究表明：研究区饮用水中氟质量浓度为0．70—4．51mg·L^-1;白菜根土中氟质量分数为182—484mg·kg^-1,萝卜根土质量分数为182～352mg·kg^-1,玉米根土中氟质量分数为209～1254mg·kg^-1;白菜可食部分氟质量分数为0．51～2．96mg·kg^-1,萝卜可食部分氟质量分数为0．34～0．50mg·kg^-1,玉米果实部分氟质量分数为0．88～1．04mg·kg^-1。通过饮用水、食物途径所致健康风险中,食人途径、饮用水途径非致癌物年健康风险分别为1．920×10^-9·a^-1,1．960×10^-8·a^-1,均低于国际辐射防护委员会（ICRP）推荐的通过饮水途径最大可接受风险水平（5×10^-5·a^-1）。     

神经网络法应用于酚类化合物对青海弧菌毒性的预测

青海弧菌对有毒酚类化合物具有强烈的敏感性,为建立酚类衍生物对青海弧菌毒性的定量结构-活性相关性(QSAR)模型,分析了16种酚类衍生物的分子结构与对青海弧菌毒性之间的相关关系,计算了酚类衍生物的分子连接性指数和分子形状指数,并优化筛选了分子连接性指数的1阶路径指数(~1χ)和分子形状指数的2阶特征指数(K_2)及1阶和2阶指数乘积值(K_4),用这3种指数与对青海弧菌的毒性进行多元回归分析,多元回归方程的决定系数R~2=0.971。为进一步提高预测精度,将这3种分子结构参数作为神经网络的输入变量,毒性值作为输出变量,采用3:2:1的网络结构,通过反向传播(BP)神经网络法获得满意的QSAR预测模型,总的相关系数r为0.996,计算得到的毒性预测值与实验值较为吻合,平均相对误差仅为1.98%,结果表明该模型具有良好的预测酚类衍生物毒性的能力,可以看出神经网络方法对酚类化合物发光菌毒性预测比多元线性回归方法的统计学意义更加明显。     

In vitro microbiological evaluation of novel 2-oxo-2H-chromene-3-carbaldehyde containing 1,3,4-thiadiazole moiety

4-(5-(Methylthio)-1,3,4-thiadiazol-2-ylamino)-2-oxo-2H-chromene-3-carbaldehyde (3) and 4-(5-(ethylthio)-1,3,4-thiadiazol-2-ylamino)-2-oxo-2H-chromene-3-carbaldehyde (4) were prepared. The structures of the newly synthesized compounds were characterized by infrared (IR), nuclear magnetic resonance (NMR) spectral data and elemental analysis. The synthesized compounds were screened in vitro for their antibacterial activities. The synthesized compounds demonstrated moderate antimicrobial activity.     

叶面喷施硅铈复合溶胶对水东芥菜重金属含量及其他品质的影响

田间小区试验研究了叶面喷Si、喷Ce以及喷Si+Ce处理对水东芥菜生长、地上部重金属Cd、As、Pb、Cr、Hg含量,以及维生素C（Vc）、可溶性糖、硝酸盐、亚硝酸盐含量等品质的影响。结果表明：叶面喷Si、喷Ce以及喷Si+Ce处理,均可以促进水东芥菜生长,增加水东芥菜地上部鲜物质和干物质重量;尤其是叶面喷Si+Ce处理后水东芥菜地上部鲜物质和干物质重量比对照分别增加了6.2%和16.2%;差异达到显著水平。与对照相比,叶面喷Si、喷Ce以及喷Si+Ce处理后水东芥菜地上部Cd含量分别下降了24.5%、22.9%、42.6%;As含量分别下降了26.4%、26.0%、40.0%;Pb含量分别下降22.5%、32.5%、36.8%;差异都达到显著水平。但是各处理对水东芥菜地上部 Cr 和 Hg 含量并无显著影响。与单独喷 Si 或单独喷Ce相比,叶面喷Si+Ce复合处理对降低水东芥菜地上部Cd和As含量效果更佳。叶面喷Si、喷Ce以及喷Si+Ce处理,还可以显著增加水东芥菜地上部Vc、可溶性糖含量,显著降低其硝酸盐、亚硝酸盐含量;同时叶面喷施Si+Ce处理后水东芥菜地上部亚硝酸盐含量是分别单独喷Si、喷Ce的80.3%和79.1%,差异达到显著水平。因此,叶面喷施Si+Ce复合处理在促进水东芥菜生长,降低水东芥菜体内重金属含量以及提高水东芥菜品质等方面的性能要优于单独喷施Si或单独喷施Ce。     

黑胸散白蚁纤维素酶的体外酶学特性

采用DNS法研究了我国广泛分布的一种低等木食性白蚁——黑胸散白蚁纤维素酶的体外酶活特性以了解其纤维素降解机制.结果表明,内切β-1,4-葡聚糖酶(EG)、纤维二糖水解酶(CBH)和β-葡萄糖苷酶(BG)这3种酶的最佳反应时间均为15 min,最佳底物浓度为1%,最适反应pH为5.6,最适反应温度为35℃.在最适反应条件下,EG、CBH和BG的活性分别达到71.3(±13.9)U/mg、5.8(±0.8)U/mg和4.1(±0.7)U/mg.EG在体外的热稳定性较差,在50℃及更高温度酶活很低或完全失活,但该酶对pH稳定性较好,在pH 3.2～8.0范围内酶活力变化不大.Native-PAGE电泳检测到该白蚁体内至少有8种不同的EG活性条带,肠道不同部位纤维素酶活性条带种类不同.这些研究表明,木食性白蚁降解纤维素是一个复杂的过程,需要多种纤维素酶的共同作用.     

深黄伞形霉(Umbelopsis isabellina)华2-1产油发酵培养条件优化

为开发微生物油脂资源,从富含油脂的土样中分离获得一株产油脂微生物——深黄伞形霉(Umbelopsisisabellina)华2-1,油脂含量达48.60%.采用单因素和正交实验方法,对深黄伞形霉华2-1的发酵培养条件进行优化研究.优化的培养条件为:葡萄糖100 g/L,酵母粉3 g/L,接种量为20%,初始pH值为5.0～6.0,MgSO4.7H2O和KH2PO4的添加浓度分别为0.5 g/L和2 g/L,培养温度为31℃,最佳发酵培养时间为168 h.华2-1在优化发酵条件下可获得菌体生物量、油脂产量和油脂含量分别为45.86 g/L、24.47 g/L和59.53%,较优化前分别提高了21.48%、33.42%和22.49%.因此,深黄伞形霉华2-1作为微生物油脂生产的新资源具有广阔的应用前景.     

Sizing of safety valves for multi-purpose plants according to ISO 4126-10

Multi-purpose plants are frequently protected with mechanical safety devices like safety valves or bursting disks. Due to many changes of recipes it must be checked regularly whether the safety devices are sufficiently sized. But the sizing procedure of individual safety devices can be very tedious. Therefore energy specific relief areas (effective relief area per kW of energy input) have been determined for approx. 60 typical solvents. They are indicated for reactors with safety devices which have a set pressure of 7 bar (abs) or 11 bar (abs). These values are independent of the size of the reactors for vaporizing systems and arbitrary safety valves. The energy specific relief areas allow the minimum required relief area quickly to recalculate if the energy input of the reactor is known. In addition, the application of solvents in multi-purpose plants can be evaluated from a safety point of few.The energy specific relief areas are calculated based on a relief of two-phase gas/liquid mixtures. The data have been determined with the non-equilibrium HNE-DS method, which takes into account the boiling delay of the liquid in the safety device and the slip between gases and liquids. The method is recommended in the international standard ISO 4126 part 10. In addition, practical advice and possible improvements are outlined. The method leads to significantly smaller relief areas than according to the API 520. For multi-purpose plants with available safety devices this method allows for a considerable expansion of the application range of reactors.     

天津市区域土壤Cd污染及其对农产品影响

研究了天津市土壤Cd元素区域分布特征,依据本次土壤调查背景参数特征和国家环境质量标准对农田土壤Cd污染进行了分级评价,天津市农田土壤存在不同级别的Cd污染。其中中-重度污染区面积约116km2,占调查面积的1.07%,主要集中在东丽区大毕庄、荒草坨,津南区双港,西青区邓店、楼家院等。在不同污染程度区农产品的调查结果表明,Cd在中-重度污染地区蔬菜中有富集和超标现象,应加强污染区土壤监测和治理工作。     

Kabrit ki gen twòp mèt: understanding gaps in WASH services in Haiti's IDP camps

Despite the enormous infusion of post‐quake aid to Haiti, cholera had killed more than 8,000 people by January 2013. Based on two mixed‐method studies of a random sample of 108 internally displaced person (IDP) camps and 168 interviews with agency representatives and recipients, this article examines the prevalence of factors that have proven most relevant to the rapid spread of cholera, particularly the provision of water and sanitation services in IDP camps. The study reveals that 30% of IDP camps had no toilets and 40% had no access to water before the outbreak, with only minimal progress after three months. Using bivariate and multivariate statistical analyses, this article explores patterns in the gaps of services with a range of variables such as NGO camp management, municipality and landowners. It offers several theoretical and policy explanations for low level of services, concluding with a series of recommendations for better coordination and management.