基于灰色聚类法的成都市大气污染评价

大气环境质量问题一直是关注的环境问题之一,而灰色聚类分析方法在很多领域已有应用。本文对成都市大气环境监测数据进行评价：采用灰色聚类分析方法,将污染因子（SO2、NO2、PM10）进行综合评价,标准化污染因子及评价指标。白化函数得到各个污染因子每年的5×4矩阵,按照聚类系数来判定综合指标类型,并进行评价。为成都市综合大气...     

Genetic polymorphisms in CYP1A1 and GSTM1 predispose humans to PCBs/PCDFs-induced skin lesions

INTRODUCTION: Polychlorinated biphenyls (PCBs) and dibenzofurans (PCDFs) are ubiquitous persistent pollutants in humans. Whether people with different genotypes are with different susceptibility to these chemicals are unknown. In a group of people highly exposed to PCBs/PCDFs, we tested the hypothesis that genotypic polymorphisms affected susceptibility for development of skin manifestations. METHODS: In 1979, approximately 2000 people in central Taiwan ingested cooking oil contaminated with PCBs/PCDFs. Skin disorder such as chloracne, abnormal nail, hyperkeratosis and skin allergy were found in PCBs/PCDFs exposed group. We recruited exposed and community background exposure subjects for blood testing and telephone-interview. Single nucleotide polymorphisms, AhR Arg554Lys, CYP1A1 Ile462Val, CYP1A1 T6235C, and GSTM1/T1 deletion, were determined. Occurrence of skin manifestations was compared among people with different genotypes while stratified by PCB exposure levels by logistic regression. RESULTS: Data on exposure, medical history, and genotypes were obtained from 393 exposed and 181 background exposure groups. Skin manifestations including chloracne, allergy, abnormal nail, and hyperkeratosis were more prevalent in exposed people in a dose-related manner. Among highly exposed individuals, combined CYP1A1-MspI mutant genotype and GSTM1-null genotype were associated with increased risk of chloracne (odds ratio 2.8, 95% confidence interval 1.1-7.6). Among intermediately exposed individuals, GSTM1 null genotype was associated with skin allergy. AhR Arg554Lys genotype and GSTT1 null genotype were not related to susceptibility to skin manifestations in PCB/PCDF-exposed population. CONCLUSION: CYP1A1 and GSTM1 genotypic polymorphisms might be related to the susceptibility to PCB/PCDF-induced skin manifestations.     

粉尘对电气设备的危害及其防治

冶金生产过程中产生的粉尘对电气设备危害极大,如造成电气设备短路,电气开关按触不良,通风不良等。采取了定期清扫粉尘,定期检查开关设备的触头及接线,提高电气设备的抗尘能力等措施后,取得明显效果。     

可持续发展的文化探源--兼论GIS在区域可持续发展中的作用

本文通过分析人类文化发展伴随生态恶化的发展历程。试图揭示人类文化与自然生态演化之间的深机制给出了二者相互作用的数学模型。并刻画了人类文化循环与自然生态循环的作用过程，同时探讨了GIS与区域可持续发展关系。     

碳纳米管对孔雀石绿的吸附特性

该文研究了碳纳米管对水中孔雀石绿的吸附性能。结果表明,碳纳米管对孔雀石绿的吸附平衡时间约为4 h左右;假二级动力学模型更适合描述碳纳米管对孔雀石绿的吸附;碳纳米管对水中孔雀石绿的吸附主要受外部传质影响;Langmuir等温模型拟合吸附数据效果最佳,并且最大吸附量为104.49 mg/g(288 K);由D-R等温模型可计算出吸附平均能量分别为29.79(288 K)、30.03(298 K)、28.05(308 K)k J/mol;吸附机制主要以化学吸附为主;随着温度的升高,碳纳米管对孔雀石绿的吸附逐渐降低;碳纳米管对孔雀石绿的吸附行为是自发进行的放热反应;离子强度的增大对吸附量有促进作用;在酸性条件下,碳纳米管对孔雀石绿的吸附量随p H的增加而增大。     

海洋环境水下电磁场激励源综述

通过总结海洋环境水下电磁场源的产生机理、基本特性、频带幅值以及观测方法,确定了不同海域普遍存在、影响程度较大并且规律性较强的场源。最终给出具有重要研究价值的典型场源,即海洋大地电磁场、海浪感应电磁场、海流感应电磁场和工频电磁场。     

天津市区能见度变化规律及影响因子相关分析

通过分析2010年天津市区的实时观测数据,结果表明:能见度有明显的年际变化、月变化和日变化规律,能见度和PM2.5及相对湿度呈现典型的负相关,不同季节条件下,能见度与PM2.5的相关性明显优于PM10,秋季能见度与颗粒物的相关性明显优于其他季节。     

电镀废水处理工程设计

电镀废水中合有氰化物,酸,碱以及六价铬,铜,锌,镉,镍等重金属污染物,毒性很大,危害严重.因此,电镀废水的治理仍是一个不可忽略的问题.本设计针对镀锌废水,根据我国现行的环保法规,采用化学沉淀法对废水进行处理.出水可达到国家污水综合排放标准(GB8996-1996).本工艺通过对离子交换法和电解法的比较,采用化学沉淀法为主体工艺,并结合过滤技术对镀锌废水进行处理,同时对主要处理构筑物和设备进行了设计计算和选型并对工艺效益和工艺成本进行初步分析,经处理后的电镀废水达到国家污水综合排放标准(GB8996-1996).