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791.
印染污泥特性及其掺煤焚烧处置的环境影响研究   总被引:1,自引:0,他引:1  
对佛山6家印染厂污泥的基本性质和重金属污染进行了分析研究。结果表明:印染污泥有机质含量较高;对照农用污泥污染物限值和城镇污水处理污泥处置混合填埋用泥质标准,Cr、Ni、Cu、Zn不同程度超标,说明印染污泥既不能农用,也不能混合填埋。污泥浸出液中重金属浓度远低于危险废物浸出毒性限值和城镇污水处理厂污泥单独焚烧用泥质的污染物限值。污泥与煤掺混焚烧烟道气中二恶英浓度在0.0125~0.022 ngTEQ/Nm3,远低于GB 18485—2001《生活垃圾焚烧污染控制标准》限值和GB/T 24602—2009《城镇污水处理厂污泥处置单独焚烧用泥质》限值。  相似文献   
792.
A pot experiment was carried out by growing 29 different genotypes (Amaranthus spp.) of vegetable amaranth under low- (0.12 mg·kg-1) and middle- (0.40 mg·kg-1) cadmium (Cd) exposure. The result showed that amaranth was vulnerable to cadmium (Cd) contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant (P<0.001) in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated (p<0.01), implying that Cd-accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxingdayemashixian (cv. Nan), a selected typical pollution-safe cultivar (Cd-PSC), and cv. Pennongjianyexian (cv. Pen), a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaCl (Cd form extracted by 1 mol·L-1 NaCl) may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.  相似文献   
793.
论环境管理会计   总被引:7,自引:0,他引:7  
如何利用环境财务会计信息为企业内部管理层进行经营决策、投资决策服务是环境管理会计的研究内容。目前,国内有关环境管理会计的研究还很欠缺。从环境成本的核算与管理,环境投资决策分析及环境业绩评价3方面对环境管理会计的核心内容进行了探讨。  相似文献   
794.
化学修饰技术可以掩蔽细胞壁上一些基团,从而使吸附量改变,利用该技术可以探讨生物吸附法去除金属离子的机理。化学修饰在环境污染治理方面有广阔的应用前景。  相似文献   
795.
采用微滤—反渗透(RO)—蒸发—结晶工艺处理某石化企业的RO浓水,实现了RO浓水的“零排放”.试验结果表明:经加碱、微滤后,污水硬度平均减小率为98.8%,排出的滤渣平均质量分数为9.4%,减少了污水中有机物和微生物对后续RO膜的污染;微滤产水无需降低pH,可直接进入RO系统,电导率减小率可达98.0%;蒸发可将总固体质量浓度由13 290 mg/L增至172 155 mg/L,产水电导率为66 μS/cm.  相似文献   
796.
The concentrations of EC, BC and dust aerosols were determined for atmospheric samples collected from an observation station in Xi'an, China. The results show that the averaged correlation coefficient between EC and BC was founded to be 0.72 with 0.81 (n = 49) in autumn, 0.70 (n = 112) in winter and 0.69 (n = 57) in spring, respectively. Absorption coefficients of dust aerosol were estimated to be 2.7 m2 g−1 in autumn and 4.4 m2 g−1 in winter. The comparison of absorption coefficients of dust aerosol with those of BC implies that BC is the principal light-absorbing aerosol over Xi'an atmosphere. By combining thermal analysis of elemental carbon and dust contents in the aerosol samples, however, the fraction of dust absorption to total light absorption is estimated to be 19% in autumn and 31% in winter, respectively.  相似文献   
797.
根据重力场非潮汐变化的波长特征讨论了由重复重力测量结果中提取地震前兆场信息的可能性。文中提出并应用场论理论中重力梯度场变化的二维散度可突出与地震有比较直接关系的孕震信息。通过对北祁连河西地区几次强震的分析研究,认为重力散度较好地反映了地震发生前震源区的孕震特征,是一种值得进一步研究的方法。  相似文献   
798.
Two typical areas, including once commercial and residential quarters of Nanjing, China, were studied by investigating soil properties especially heavy metals of soils in various cultural layers formed in different Chinese Dynasties. The age of the soil profiles was dated by both archaeological and 14C chronological methods. The results showed that urban soils in the old commercial/workshop quarter of Nanjing were generally contaminated by heavy metals Cu, Zn, Pb, but their concentration levels varied significantly among the cultural layers formed in different dynasties. The substantial increase of heavy metals appeared in three historical periods, i.e., South Dynasty (222-589 AD), the earlier Ming (1368-1644 AD) and the late Qing (1644-1912 AD) in one area. The tremendous input and storage of heavy metals in soils was explained by the primitive smelting and the strengthened metal processing activities, which might be due to the requirement of weapon making or other industries, in the changing social conditions of the corresponding periods. Soils in the once noble political, cultural centers did not show significant increase of heavy metals. The difference in the distribution pattern of heavy metals revealed the contrasting history of the site uses. The change of contaminant level in soils is believed to be a reflection of various human activities in the city during the past 20 centuries.  相似文献   
799.
亚热带小区域水平上土壤质量时空变化的定量化评价   总被引:4,自引:0,他引:4  
亚热带小区域水平上土壤质量时空变化的定量化评价王效举,龚子同(中国科学院南京土壤研究所,南京210008)QuantitativeEvaluationofSoilQualityChangesinTimeandSpaceataSmallAreaLeve...  相似文献   
800.
采用热水萃取分离技术回收聚醚残渣中J的聚醚和膦酸二氰钾,考察了萃取温度、结晶温度、水洗条件等因素对产品回收情况的影响。工业试验结果表明:聚醚回收率大于75%,磷酸二氢钾的平均回收率为70%.工业化试生产得到磷酸二氢钾和聚醚的产品质量分别达到HG2321-92工业品一级标准和该厂制定的GEP560S企业标准。该技术具有聚醚和磷酸二氢钾回收率高、工艺简单等特点,且经济效益、环境效益和社会效益显著。  相似文献   
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