硅酸盐、腐殖酸对Cr污染土壤中小白菜生理及吸铬量的影响

针对在铬污染区土壤中的叶菜类吸铬量是果菜类2~3倍,以及硅酸盐或腐植酸在重金属污染土壤上的最佳施用量研究较少的问题,为保障蔬菜的品质安全,文章通过土壤盆栽试验,研究硅酸盐、腐殖酸不同用量对Cr污染土壤中小白菜(Brassica Chinensis)生理指标和吸铬量的影响.结果表明,施低质量分数的硅酸盐(1.0 g·kg-1)效果最佳,既能提高受Cr污染小白菜的生物量、叶绿素相对含量,又能减轻Cr毒害对抗氧化酶系统中SOD酶活性的抑制,缓解小白菜受到的过氧化胁迫,有效降低小白菜吸铬量;高质量分数硅酸盐(2.0 g·kg-1)对生长产生抑制.腐殖酸在设计的3个质量分数水平上均不能有效降低小白菜吸铬量,对生长的促进作用也不明显.     

Residue of pentachlorophenol in freshwater sediments and human breast milk collected from the Pearl River Delta, China

Pentachlorophenol (PCP) was investigated in freshwater sediments and human breast milk collected from the Pearl River Delta, China. The average level of PCP in river sediments was 7.93 ng/g based on dry weight, ranging from 1.44 to 34.4 ng/g. As to the sediments from fishponds, samples from Zhongshan had the highest PCP levels (37.5 ng/g on average), followed by Dongguan (21.1 ng/g on average) and the least in Shenzhen (3.69 ng/g on average) and Shunde (2.20 ng/g on average). Negative relationship was obtained between the PCP level and pH value in sediment (r=0.553, n=13, p<0.05), while positive relationship was found between the PCP levels and the total organic matter (TOM) levels in sediment (r=0.700, n=17, p<0.01). These results indicated that pH and TOM played important roles during the process of PCP settling down to the sediment. PCP was also detected in human breast milk with an average of 2.15 ng/g. The PCP concentration increased with the age increasing of donors. The estimated PCP body burden for mother, daily and yearly PCP intake of infants ranged from 0.16 to 4.17 mg/person, from 0.26 to 10.23 mug/infant.day and from 0.09 to 3.73 mg/infant.year, respectively.     

The Reuse of Urban and Industrial Waste in Tai-Lin-Pu Reclamation Project, Taiwan

This study introduces the principles of KMG's (Kaoshiung Municipal Government) dealing with the non-poisonous urban and industrial waste through reclamation of shore land in reinforcing a sense of coastal protection and land development in Tai-Lin-Pu coastal area, southern Taiwan.

Through a series of experimental studies, we found that substitutes of coarse aggregate with a broad spectrum of integrating slag powder, fly ash, and cementitious material can be obtained with a benefit up to 80% saving of cement. the integrated aggregates from the non-poisonous industrial wastes were subsequently made into armour units and used in the field tests at Tai-Lin-Pu coastal area, where the shorelines are seriously eroded. After being subjected to several severe typhoon advents, the results showed that the waste-made units used as the protection breakwater, together with construction wastes and excavated soil as the filling material, prove to be an effective practice in utilizing recycled urban waste to reclaim erosive shore lands. Moreover, this study also demonstrates that through detailed analysis of the waste characteristics, scrap material could be turned into valuable construction aggregates, and highlights the value of non-poisonous urban and industrial waste as a alternative resource for the shore protection engineering.     

Photolysis of polycyclic aromatic hydrocarbons in water

We have studied the photochemical reactions of eight polycyclic aromatics and heteroatom analogs (PAHs). Quantum yields and rate constants in sunlight and at single wavelengths were measured and half-lives of the PAHs as a function of the time of year were calculated. Product studies and the effect of humic acid and oxygen on rates are reported.     

珠江口广州海域石油烃的分布特征

据2003～2007年春、夏、秋季珠江口广州海域海水与2007年夏季沉积物中石油烃含量的调查结果,分析了该海域表层水体和表层沉积物的石油烃分布特征。结果表明,调查海域海水中石油烃含量为0.02～0.81 mg/L,平均含量为0.13mg/L;沉积物中石油烃含量为(51～1 910)×10-6,平均含量为544.9×10-6,石油烃含量较高的海域主要分布在南沙港、黄埔港-莲花山及蕉门水道出海口海域。石油烃浓度夏季最高,秋季居中,春季最低。与15 a前相比,广州海域水样与沉积物样中的石油烃浓度都有较大幅度的上升。     

三株驯化细菌苯酚降解率的比较研究

文章对从农药厂、三化厂和焦化厂废水中分离的细菌NYC-1A、SHC-1B和JHC-1C,通过逐步提高苯酚浓度对它们加以驯化,采用模拟SBR工艺对驯化前后三株细菌对含有苯酚的培养液的处理效率进行了比较研究。结果表明：细菌湿重为1g／L,苯酚培养液经处理16h后,JHC—1C的苯酚降解率最高为89．59％;其次为NYC-1A,降解率为77．88％;SHC-1B的降解率最低,降解率为53．31％。驯化后三株细菌处理苯酚培养液3h,NYC-1A降解率最高为76．37％,SHC—1B的降解率为69．29％,JHC—1C的降解率为45．66％。通过本文研究,表明苯酚降解菌经驯化后可有效提高降解苯酚的效率。     

内蒙古自治区“十一五”煤炭发展对大气环境影响分析

通过对内蒙古1995～2005年煤炭消费量及排污量关系分析可知,煤炭消费与大气污染物排放的相关性较大,在此基础上,分析预测内蒙古"十一五"煤炭消费将对大气环境产生的影响,分析表明:煤炭发展对未来内蒙古的区域和城市大气环境影响较为显著,应引起足够重视.必须对老污染源进行脱硫,同时提高新污染源SO2脱硫效率,加大节能降耗、减排的力度,才能保证能耗和大气污染物排放总量目标的顺利实现.     

气相色谱分析空气和废气中二甲基亚砜

空气和废气中二甲基亚砜分析国内还未有相关分析方法报道,本文根据二甲基亚砜的物化性质采用无水乙醇吸收空气和废气中二甲基亚砜。毛细柱分离、气相色谱分析氢离子火焰检测器检测。实验过程方便、样品分析快速。通过实验总结出合适的采样条件和分析条件并对该物质采样流量、采样时间;标准溶液放置时间、样品存放时间做了详细的实验,得各项数据均符合质量控制要求相关系数为0.9991,标准偏差在：0.01-0.42之间,采样效率在：91.2%-98.7%之间,能满足环境监测工作的需要。     

现行土层地震反应分析存在的问题

工程上广泛应用的现行土层地震反应分析方法即为借助快速傅里叶变换和迭代法的等效线性化频域方法.简要介绍了现行土层地震反应分析方法,结合具体算例,再现了现行土层地震反应分析方法在实际应用中存在的四个问题,一是对个别输入加速度时程的离散点个数无效,二是底部存在软夹层计算结果异常,三是输入地震动较大、场地较软时计算结果不合理,四是可能出现死循环现象.针对这四个问题提出了现行土层地震反应分析方法改进的方向,对以后土层地震反应分析方法的发展进行了展望.     

Cd2+对长江华溪蟹谷胱甘肽系统的影响

摘要：本实验采用急性毒性方法,研究了镉（Cd2+）对长江华溪蟹（Sinopotamon yangtsekiense）肝胰腺和鳃谷胱甘肽系统的影响。Cd2+浓度设置为7.25、14.5、29、58和116 mg/L,同时设对照组。分别在24、48、72和96 h用分光光度法测定了还原型谷胱甘肽（GSH）和氧化型谷胱甘肽（GSSG）含量,谷胱甘肽过氧化物酶（GPx）、谷胱甘肽硫转移酶（GST）和谷胱甘肽还原酶（GR）活力以及GSH/GSSG比值。结果显示,随着Cd2+浓度的增加和处理时间的延长,肝胰腺中GSH含量呈现逐渐降低的趋势,在96 h、Cd2+浓度116 mg/L时GSH含量降至最低值[（28.805±2.239） mg/g];GPx活力先升后降;GSSG含量和GST与GR活力均无显著变化。鳃中GSH、GSSG含量和GPx活力的变化趋势与肝胰腺基本一致,GST和GR活力则随着Cd2+浓度的增大和处理时间的延长逐渐降低,在96 h、Cd2+浓度116 mg/L时GST和GR活力较对照组分别下降了44%和79%。肝胰腺和鳃中GSH/GSSG比值随着Cd2+浓度的增大和处理时间的延长逐渐降低。结果表明,Cd2+对GSH和GSSG含量,GPx、GST、GR活力均产生了不同程度的影响;GSH/GSSG比值的变化能灵敏反映Cd2+对水生动物的胁迫程度及毒性大小,可作为一种准确敏感的生物学指标用以指示镉污染。