企业安全管理基础条件的建设

本文以石油石化和民航行业禁烟状况为例,阐述安全管理基础环节建设的完善与否,直接影响安全管理效果。文章主要探讨通过建设良好的安全管理基础条件,将繁杂的安全工作进行分解,把企业预防生产事故的工作,逐步量化执行。把握住管理制度编制与管理档案的两个抓手,进而实现安全条线的精细化管理,推动安全生产管理体系的良好运转,使被动解决问题转向主动规避风险。     

2,2′,4,4′-四溴联苯醚的好氧微生物降解

从北京高碑店污水处理厂活性污泥中筛选出1株能好氧降解2,2′,4,4′-四溴联苯醚(BDE-47)的细菌,并对其降解特性及有关蛋白质进行分析,目的是了解好氧条件下BDE-47的微生物降解机制.BDE-47降解菌通过平板划线法获得,其16S rDNA与不动杆菌(Acintobacter sp.)的相似度最大,为90％.采用250 mL锥形瓶研究了所得菌对BDE-47的降解情况,在BDE-47初试浓度为146 μg·L-1的条件下,经过63 d的培养,所得菌降解了45.44％的BDE-47,降解产物主要为4-OH-联苯醚,菌量增加了7倍左右.分别以BDE-47和酵母提取物为碳源培养所得菌2周,然后各自提取蛋白质,通过蛋白质双向电泳及质谱检测,发现了与BDE-47降解有关的一些特异蛋白质.本研究表明,在好氧条件下,细菌可以BDE-47为碳源生长,其过程涉及多种蛋白质的作用.     

温度对合成钛酸盐纳米材料的影响及其对水中Cd (Ⅱ)的去除效果

为有效去除水中Cd（Ⅱ）,以TiO₂纳米粉和NaOH为原料,调节水热反应温度分别为100、120、150和190℃,制备出了不同形貌的TNs（钛酸盐纳米材料）,分别记为TNs-100、TNs-120、TNs-150和TNs-190,并对其形貌、结构、比表面积、化学组成等物理化学性能进行了表征;通过对水中Cd（Ⅱ）的静态吸附试验,考察了TNs对Cd（Ⅱ）的吸附性能.结果表明:随着合成温度的升高,TNs的形貌逐渐从纳米片演变成纳米管,管长逐渐变长,最后变成纳米棒.TNs-100的晶型结构主要是锐钛矿型;随着温度升高,结晶度逐渐增强;TNs-190出现了部分金红石相.TNs-150对Cd（Ⅱ）的吸附能力最强,最大平衡吸附量为254.66 mg/g,最佳吸附pH为5.0.再生的TNs-150对Cd（Ⅱ）循环吸附6次的去除率和解吸率均可达93%以上.TNs-150对Cd（Ⅱ）的吸附过程符合准二阶动力学方程和Langmuir吸附等温模型,吸附机制主要是TNs层间Na+和H+与溶液中Cd（Ⅱ）的离子交换.研究显示,TNs的饱和吸附量均高于同类吸附剂,能有效去除水中Cd（Ⅱ）.      

利用餐厨垃圾湿热处理脱出液制备液态菌肥研究

以餐厨垃圾湿热处理脱出液为发酵培养基,选用圆褐固氮菌(Azotobacter chroococcum)作为实验菌种制作固氮液态菌肥。测定了圆褐固氮菌的主要生理特性,将其接种于餐厨湿热处理脱出液中进行培养,确定最佳发酵时间,并分别测定发酵的最佳初始p H值、接种量、培养温度、摇床转速、装液量、脱出液与水的混合比例。结果表明:圆褐固氮菌在餐厨湿热处理脱出液中最佳发酵时间为36 h,发酵最佳初始p H值、接种量、培养温度、摇床转速、装液量、脱出液与水的混合比例依次为7.5、1%、30℃、150 r/min、50 m L(250 m L锥形瓶)、1∶1。圆褐固氮菌在餐厨垃圾湿热处理脱出液中进行培养后,可达到液态菌肥的活菌数标准。     

异烟酸-吡唑啉酮比色法测定海水氰化物实验条件的选择

对异烟酸-吡唑啉酮比色法中氰化物水样保存时间、氯胺T含量、水浴时间和水浴温度进行显色反应条件选择。结果表明:（1）浓度范围为0.5~5 μg/L的氰化物密封水样在pH为12左右的有效保存时间达24 h,在（24~30）h内的氰化物损失率与其氰化物含量呈明显的二次方程拟合关系;（2）在氰化物含量低于4 μg下,氯胺T最佳量为2 mg,且氯胺T增量（即超过最佳量的量）与吸光值降低值呈明显的正相关线性关系;（3）含量低于4 μg的氰化物水样中显色稳定的水浴时间均在20 min之内;（4）含量低于4 μg的氰化物水样中显色灵敏度最高时的水浴温度均在40℃左右。     

Biodegradation of 2-methylquinoline by Enterobacter aerogenes TJ-D isolated from activated sludge

Bacterial strain Enterobacter aerogenes TJ-D capable of utilizing 2-methylquinoline as the sole carbon and energy source was isolated from acclimated activated sludge under denitrifying conditions. The ability to degrade 2-methylquinoline by E. aerogenes TJ-D was investigated under denitrifying conditions. Under optimal conditions of temperature (35℃) and initial pH 7, 2-methylquinoline of 100 mg/L was degraded within 176 hr. The degradation of 2-methylquinoline by E. aerogenes TJ-D could be well described by the Haldane model (R² > 0.91). During the degradation period of 2-methylquinoline (initial concentration 100 mg/L), nitrate was almost completely consumed (the removal efficiency was 98.5%), while nitrite remained at low concentration (< 0.62 mg/L) during the whole denitrification period. 1,2,3,4-Tetrahydro-2-methylquinoline, 4-ethyl-benzenamine, N-butyl-benzenamine, N-ethyl-benzenamine and 2,6-diethyl-benzenamine were metabolites produced during the degradation. The degradation pathway of 2-methylquinoline by E. aerogenes TJ-D was proposed. 2-Methylquinoline is initially hydroxylated at C-4 to form 2-methyl-4-hydroxy-quinoline, and then forms 2-methyl-4-quinolinol as a result of tautomerism. Hydrogenation of the heterocyclic ring at positions 2 and 3 produces 2,3-dihydro-2-methyl-4-quinolinol. The carbon-carbon bond at position 2 and 3 in the heterocyclic ring may cleave and form 2-ethyl-N-ethyl-benzenamine. Tautomerism may result in the formation of 2,6-diethyl-benzenamine and N-butyl-benzenamine. 4-Ethyl-benzenamine and N-ethyl-benzenamine were produced as a result of losing one ethyl group from the above molecules.     

Iron and lead ion adsorption by microbial flocculants in synthetic wastewater and their related carbonate formation

Although microbial treatments of heavy metal ions in wastewater have been studied, the removal of these metals through incorporation into carbonate minerals has rarely been reported. To investigate the removal of Fe^3＋ and Pb^2＋, two representative metals in wastewater, through the precipitation of carbonate minerals by a microbial flocculant （MBF） produced by Bacillus mucilaginosus. MBF was added to synthetic wastewater containing different Fe^3＋ and Pb^2＋ concentrations, and the extent of flocculation was analyzed. CO2 was bubbled into the mixture of MBF and Fe^3＋/Pb^2＋ to initiate the reaction. The solid substrates were analyzed via X-ray diffraction, transmission electron microscopy and energy dispersive spectroscopy. The results showed that the removal efficiency decreased and the MBF adsorption capacity for metals increased with increasing heavy metal concentration. In the system containing MBF, metals （Fe^3＋ and Pb^2＋）, and CO2, the concentrated metals adsorbed onto the MBF combined with the dissolved CO2, resulting in oversaturation of metal carbonate minerals to form iron carbonate and lead carbonates. These results may be used in designing a method in which microbes can be utilized to combine CO2 with wastewater heavy metals to form carbonates, with the aim of mitigating environmental problems.     

浸提条件对土壤中阴离子浓度的影响

文章通过测定青海省民和县中川乡中度盐碱条件下土壤水溶性氯离子和硫酸根离子浓度,分析浸提时间和浸提时的水土比对测定结果的影响。旨在明确浸提条件对离子色谱法测定土壤中水溶性氯离子和硫酸根离子的影响。结果表明,水土比为20∶1时,浸提时间60 min测定的氯离子和硫酸根离子浓度最高,而水土比为10∶1时,浸提30 min测定的浓度最高。     

一株源自海洋环境多环芳烃降解菌的筛选、鉴定及适宜降解条件研究

利用以菲为唯一碳源的选择性富集培养基,从天津港6号码头潮间带表层沉积物中分离到1株多环芳烃降解细菌,命名为DHD,经16SrDNA序列比对结果显示,该菌株属门多萨假单胞菌(Pseudomonas mendocina)。DHD能以多种多环芳烃化合物包括萘、菲、蒽、芘为唯一碳源和能源生长。以菲为代表,通过摇瓶培养实验考察了该菌株降解多环芳烃的适宜培养条件为:酵母浸粉为氮源,初始pH 9.0,培养温度30℃,摇床转速为200 r/min。     

正交实验在气浮法条件筛选中的应用研究

正交试验是研究多因素多水平的一种设计方法,它是根据正交性从全面试验中挑选出部分有代表性的点进行试验,这些有代表性的点具备了“均匀分散,齐整可比”的特点,正交试验设计是分析因式设计的主要方法。是一种高效率、快速、经济的实验设计方法。将正交试验选择的水平组合列成表格,称为正交表。本文选择对溶气气浮法为研究对象,通过PAC的加入量、沉降时间、搅拌强度和搅拌时间等因素对废水的混凝处理效果有较大影响,为确定各因素的最佳值和影响效果的主次关系,选择影响较大的因素,采用正交实验确定设备最佳的运行条件。