基于静电纺丝膜的Fenton法降解双氯芬酸钠

通过浸渍法将铁盐负载于静电纺丝纤维膜制备了类Fenton催化剂,并通过扫描电子显微镜（SEM）对静电纺丝膜进行了表征,研究了该催化剂降解双氯芬酸钠的特性及其重复利用率。结果表明,静电纺丝纤维膜反应前后膜结构良好,反应过程中铁离子几乎无溶出;膜对双氯芬酸钠有一定的吸附能力,去除率约为6.96%。当双氯芬酸钠初始浓度为20 mg·L-1,按0.310 g·（100 mL）-1比例加入催化剂时,H2O2最佳用量为340 mg·L-1。溶液的初始pH值对实验结果影响较大,酸性条件更利于双氯芬酸钠的降解,最佳pH值为3.14,但该催化剂所适用的pH值范围较之传统Fenton法有明显拓展。所制备的催化剂重复利用率高,循环使用4次后,催化活性无明显改变,4 h的去除率依然高达95%以上。反应中双氯芬酸钠主要生成乙酸等小分子化合物,最终可氧化为CO2和H2O。     

响应面法优化石油降解菌性能的研究

从延长油田石油污染土壤中筛选出4株能以原油为唯一碳源生长的细菌单菌株,鉴定其优势菌株YC-2为枯草芽孢杆菌;利用响应面法进行实验设计,选定培养温度、pH值、氮磷比以及盐度为影响因素,对原油含量为0.5%的培养基进行YC-2菌株降解工艺优化,得到了原油降解率与4种因素之间的非线性回归方程,确定了降解原油的最优工艺条件:培养温度28℃;pH值6.5,氮磷比5.2:1,盐度0.45%。在最优条件下,预测降解率为53.9%,实验验证值为52.5%,结果显示,建立的模型具有较高的精度。     

热活化过硫酸钾降解呋虫胺

以新烟碱类杀虫剂呋虫胺为目标污染物,以过硫酸钾为氧化剂,研究不同热活化条件下过硫酸钾对呋虫胺降解率的影响。实验结果表明:呋虫胺的降解率与溶液中过硫酸钾的浓度成正比;随着温度的升高,呋虫胺的降解率也逐渐升高;虽然中性时呋虫胺的降解率稍高于酸性和碱性时的降解率,但pH的变化对呋虫胺的降解率影响不大;Cl-和HCO3-对反应的影响比较复杂,当溶液中的Cl-和HCO3-的浓度低于5 mmol/L时,均促进呋虫胺的降解,而浓度升高时则抑制呋虫胺的降解;通过添加自由基捕获剂发现,该反应体系中同时存在·SO4-和·OH,但起主要作用的是·SO4-。     

铜绿假单胞菌NY3及突变株代谢油污泥同步产胞外聚合物的特性

油污泥属危险性固体废弃物,大量排放已成为石化企业可持续发展的障碍。利用铜绿假单胞菌NY3及突变株,将油污泥转化为生物质,并研究了其特性。研究表明,NY3、NB1D、 NB2D及NB12DD均能降解油污泥中烷烃,但NY3、NB1D和NB2D菌对分子量较高烷烃(从C17~C32)的降解率比双突变菌NB12DD分别平均提高19.68%、28.76%和24.04%。铜绿假单胞菌NY3及突变株能直接将油污泥中烃类转化为胞外聚合物。与未加共代谢碳源相比,葡萄糖作为共代谢碳源时(培养液中表观油浓度达15 g·L-1),培养120 h后,NY3 、NB1D、NB2D、NB12DD菌胞外聚合物产量分别提高83.3%、79.8%、20.6%和62.9%,且碱性条件有利于各菌株高效降解油转化为生物质,pH为8~9时,其胞外聚合物产量均最高,分别达到8.1、4.34、4.94和7.15 g·L-1,野生菌NY3转化碳源为生物质转化率最高,为52.75%。结构和组成分析表明,胞外聚合物主要为糖蛋白,蛋白4.4%,总糖44.1%,蛋白与糖的连接方式为O-糖苷键链接,91.1%大分子粒径分布在33.0~716.9 μm范围。     

白腐真菌GanodermaSinense对镉和蒽的去除能力

重金属和有机物复合污染是水处理中的难题。本研究发现一株白腐真菌Ganoderma Sinensis不仅可以通过富集作用去除重金属镉(Cd),而且对蒽具有降解能力。当Cd的浓度为10~30 mg/L时,该菌株对Cd的去除率为6.78%~21.9%;当蒽的浓度为10~30 mg/L时,菌株对蒽的降解率为18.25%~33.3%;当Cd和蒽同时存在于培养基中时,随着Cd浓度的增加(10~30 mg/L),对菌株的生物量及蒽降解的抑制作用也在增大;而随着蒽浓度的增加(10~30 mg/L),菌株的生物量及Cd的富集能力并未受到显著的影响。实验结果表明,该菌株有望用于镉和蒽复合污染的水体处理。     

巢湖低温高效聚磷菌的筛选及其特性

采用低温富集培养及混合平板分离技术,从巢湖底泥中分离筛选得到2株在低温下仍具有较高效能的菌株D3、D6,经过厌氧/好氧交替培养,2种菌株在低温下(8℃)的除磷率均达到80%以上。在低温下,研究了pH、微量元素对2株菌株生长及除磷率的影响,实验结果表明,2株菌都具有广泛的温度适应性,适宜其生长和除磷的pH为中性偏碱,微量元素的缺乏对2株菌株的生长和除磷效果有不同程度的不良影响。染色观察显示,厌氧培养时菌体内聚羟基丁酸(PHB)颗粒明显增多,转为好氧培养后异染颗粒增多,为典型的聚磷菌特征。经鉴定,2株菌均属假单胞菌属。     

石油降解菌Pseudomonas stutzeri TH-31的分离与降解条件优化

使用稀释富集法,从大港油田采油废水处理站生化池中定向快速的分离出多株高效石油降解菌株。对分离获得的1株优势菌株进行生理生化和分子生物学鉴定,显示属于Pseudomonas stutzeri的1个新菌株,命名为Pseudomonas stutzeri TH-31。通过批次实验,对菌株TH-31的生长条件和石油降解条件进行了优化,经过条件优化,P.stutzeri TH-31在初始pH 7,原油投加量为300 mg/L,35℃培养5 d后,获得最高石油烃降解率92.7%。     

Risk Assessment of 26 Polycyclic Aromatic Hydrocarbon (PAH) Compounds in Parkıng Garages

The aim of this study was to determine the level of 26 polycyclic aromatic hydrocarbons (PAHs) at parking garages and to provide the necessary annual information based on occupational inhalation exposure and non-occupational inhalation exposure, which carry risks for the environment. For this purpose, 22 samples were collected continuously from both gas and particulates phase PAHs from two parking garages at Konya City Center, Turkey. The exposure-based risk of these samples was evaluated using concentrations of the carcinogenic PAH compounds. None of the 26 PAHs measured had values exceeding the recommended exposure limits (RELs) standard values for inhalation rate recommended by the World Health Organization (WHO). Exposure levels of gas and particulate PAHs for the occupational group and the public (children and adults who spend time in shopping centers) were found to be 0.07–28.24 μgm^?3 and 0.05–5.753 μgm^?3, respectively, representing levels two to four times higher than those at the control site. Maximum daily inhalation of B[a]Py was estimated at 1.33 ngd^?1 for exposure of the public and as 274 ngd^?1 for the occupational group. It is believed that traffic makes a substantial contribution to the PAH profile, which had relatively high concentrations of naphthalene (Napth) and coronene (Coro). Highly carcinogenic dibenzo(a,l)pyrene (B[al]Pyre) was found in the ambient air at two parking garages. Napth and phenanthrene (Phen) were the main compounds found in nearly all the tested samples. In this study, benzo[e]pyrene (B[e]Py) was used as a reference for PAHs because its concentration is stable and does not change seasonally. Considering the importance of these compounds in relation to human health, the aim of this work was to characterize and quantify the more toxic PAHs in parking garages. Conducting PAH sampling and their chemical analysis is very costly and labor intensive. This study produced data that can be a powerful tool for environmental forensics.     

基于化工生产过程历史数据的报警优化方法研究

为了有效降低报警装置漏报率和误报率,基于化工生产的过程历史数据,探讨了报警优化的两种方法。以误报率和漏报率为优化指标,建立报警阈值目标函数,从最小化目标函数的角度出发,采用数值优化的方法进行报警阈值的优化设计。基于报警时长的变异系数,应用自适应报警延时方法来降低报警数量。实例研究表明,应用基于化工生产过程历史数据的方法,可有效减少无效报警数量,降低误报率和漏报率,提高报警质量,对于提高石化生产过程的安全性具有积极意义。     

Effects of environmental temperature on the thermal runaway of lithium-ion batteries during charging process

Lithium-ion batteries with relatively narrow operating temperature range have provoked concerns regarding the safety of LIBs. In this work, a series of experiments were conducted to explore the thermal runaway (TR) behaviors of charging batteries in a high/low temperature test chamber. The effects of charging rates (0.5 C, 1 C, 2 C, and 3 C), and ambient temperature (2 °C, 32 °C and 56 °C) are comprehensively investigated.The results indicate that the cell exhibited greater thermal hazard at the high charging rate and ambient temperature conditions. As the charging rate increased from 0.5 C to 3 C, more lithium intercalated in the anode prompt the TR triggered in advance, the TR onset temperature decreased from 297.5 °C to 264.7 °C. In addition, the charging time decreased with the elevated ambient temperature, resulting in a relatively higher TR onset temperature and lower maximum temperature, and the average TR critical time declined by 115–143 s. Finally, the TR required less heat accumulation with increasing of charging rate and ambient temperature, and the heat generation of side reaction played a substantial role that accounted for approximately 54%∼63%. These results provide an insight into the charging cell thermal runaway behaviors in complex operation environments and deliver valuable guidance for improving the safety of cell operation.