Genotoxic effects of two different classes of insecticide in developing chick embryos

Pesticides provide considerable protection against pest population; however, rampant accumulation of these chemicals into varied habitats across the globe necessitates the need for a careful screening of each chemical due to toxic manifestations. In the current study, the genotoxic potential of two different classes of commercial insecticides – chlorpyrifos and cypermethrin combination and Spinosad, a naturalyte were compared. Rhode Island Red chick embryos were exposed to different doses of either of these insecticides individually, by in ovo treatment. Genotoxicity was then evaluated through micronucleus (MN) test and Comet assay. The combination insecticide exposure at low doses of 0.05 and 0.1 μg/egg induced DNA damage as evidenced by an increased tail moment in the Comet assay. Further, the presence of micronucleated erythrocytes and also various abnormal cells including dacryocytes, microcytes, erythroplastids, squashed/notched nuclei, and spindle-shaped erythrocytes in the blood smear consolidates indicate the presence of insecticide-induced genotoxicity. Spinosad, however, was found only mildly genotoxic but at a high dose of 1.5 mg/egg. The results indicate that usage of naturalyte insecticide may be a better option to minimize the harmful effects of chemical insecticides.     

石化行业应用PDCA与6S结合的安全管理模式探讨——以催化裂解工艺为例

随着科学技术的不断进步和新材料、新工艺的不断应用,石化企业危险化学品的种类和数量逐渐增多,危险源和安全隐患日益突出,石化企业的发展迎来了安全生产的全新挑战。论述了PDCA循环管理和6s管理的概念、含义及实施步骤,分析了催化裂解阶段包括原料产品、反应装置等方面的危险性,提出将PDCA循环与6S管理相结合的管理模式应用到石化企业催化裂解阶段的具体内容和注意事项,应用PDCA与6S相结合的管理,有助于进一步创新石化企业安全管理模式,提高企业的安全管理水平。     

从粉煤灰中提取多种微细氧化物的研究

将粉煤灰与Na2CO3按一定的比例混合后焙烧,采用酸碱联合法提取粉煤灰中氧化硅、氧化铝和氧化铁,分析了工艺条件对粉煤灰中氧化物提取率的影响。实验结果表明,从粉煤灰中提取氧化物的最佳条件是:碳酸钠与粉煤灰的比例0.6∶1.0,焙烧温度850℃、盐酸浓度4 mol/L,氢氧化钠浓度2.6 mol/L,浸取时间约6 h。在此条件下得出微细氧化硅、氧化铝、氧化铁的晶体,其平均粒度分别为氧化硅1.107μm,氧化铝1.334μm,氧化铁0.783μm。     

环境类高等职业教育产学研用合作机制研究

环境类高等职业教育具有鲜明的非行业背景和人才需求领域广泛而应用岗位相对集中的特殊性。在对国内部分环境类高职院校和环境类高职专业就产学研用合作机制及运行模式实地调研的基础上,对现存的环境类高职院校产学研用合作模式进行了深入分析,提出了"依托政府,实施‘双轨并行’工学结合"的产学研用合作机制与运行模式。     

煤岩瓦斯复合动力灾害机理研究进展与展望

随着我国煤矿快速进入深部开采,煤岩瓦斯复合动力灾害日渐成为威胁深部煤炭安全高效开采的重大灾害,研究其发生机理成为煤矿安全领域新的重大科学问题。本文首先在调研统计的基础上,阐述我国煤岩瓦斯复合动力灾害的发生规律和主要破坏特征,从定性和初步定量研究角度对煤岩瓦斯复合动力灾害机理的研究现状进行综述分析,然后介绍笔者近年来在受载含瓦斯煤岩组合体耦合失稳诱发复合动力灾害机制方面的研究进展,最后展望煤岩瓦斯复合动力灾害机理研究中亟待解决的问题及未来研究方向。     

高烈度地震区隧道软硬围岩交接段刚柔并济抗减震技术研究

为提高高烈度地震区隧道抗震性能,以某铁路隧道为研究背景,分析3种抗减震措施下隧道不同监测点隧道拱顶沉降、边墙收敛、衬砌结构PGA及最小安全系数,通过对比分析得到最优抗减震措施.结果表明:相比于工况1,工况2隧道拱顶沉降减小10.54％ ～81.10％,边墙收敛减小13.92％ ～78.77％,衬砌结构PGA减小31.4...     

Treatment of 2-phenylamino-3-methyl-6-di-n-butylaminofluoran production effluent by combination of biological treatments and Fenton＇s oxidation

High strength refractory organic stream is produced during the production of 2-phenylamino-3-methyl-6-di-n-butylaminofluoran （One Dye Black 2, abbr. ODB 2）, a novel heat-sensitive material with a promising market. In this study, a combination of acidificationprecipitation, primary biological treatment, Fenton＇s oxidation and another biological treatment was successfully used for the removal of COD from 18000-25000 mg/L to below 200 mg/L from the ODB 2 production wastewater in a pilot experiment. A COD removal of 70%-80% was achieved by acidification-precipitation under a pH of 2.5-3.0. The first step biodegradafion permitted an average COD removal of 70% under an hydraulic residence time （HRT） of 30 h. By batch tests, the optimum conditions of Fenton＇s oxidation were acquired as： Fe^2＋ dose 6.0 mmol/L; H2O2 dose 3000 mg/L; and reaction time 6 h. The second step biological treatment could ensure an effluent COD below 200 mg/L under an HRT of 10 h following the Fenton＇s treatment.     

饮水中非挥发性有机污染物致突变性的防治对策

针对饮水致突变物的主要成因研究了减少饮水致突变活性的措施。结果表明：进厂源水生物膜预处理,可使致突变前体物,如藻、腐殖酸、总有机碳等含量分别减少68.2％、23.9％、37.2％,使水厂加氯量减少50％,最终使所制饮水的致突变件减少30％。改革加氯消毒方法可使饮水致突变活性降低,不同消毒剂所致致突变活性顺序为Cl₂＞ClO₂Cl₂＋ClO₂＞源水,Cl₂＋ClO₂等量联合消毒优于单一加氯消毒法,既可提高所试甲型肝炎病毒、脊髓灰质炎病毒及大肠杆菌ｆ₂噬菌体的灭活效果一至数倍;又可使饮水中CHCl₃,减少91.5％－96.5％,致突变活性减少27.6％。     

污染底泥修复研究探讨

文章概括介绍了污染底泥的修复技术及各自的特点,探讨了底泥修复中存在的问题及今后的发展趋势。目前底泥修复主要有物理修复、化学修复和生物修复三大类技术。物理修复见效快,但成本高;化学修复成本较低但易造成二次污染;生物修复投入低,处理量大,但处理效率低,难以见效。将这三类技术联合使用,取长补短,具有较广阔的发展前景。     

生态工程组合工艺应用于城市污水处理厂尾水深度处理

针对城市污水处理厂尾水的特点,采用生态氧化池／垂直流人工湿地／自然湿地生态工程组合工艺对其进行深度处理,重点分析了运行效果和去除机理。数据结果表明,该工艺运行稳定,系统出水COD,BOD5,NH3-N和TP平均分别为14．4,3．4,0．84,0．19mg／L,平均去除率均在65％以上,出水水质达到《地表水环境质量标准》（GB3838-2002）中Ⅳ类标准。