Variation and removal efficiency of assimilable organic carbon (AOC) in an advanced water treatment system

This study investigates the microorganism growth indicator and determines the assimilable organic carbon (AOC) content at the Cheng-Ching Lake Advanced Water Treatment Plant (CCLAWTP) in Kaohsiung, Taiwan. Notably, AOC is associated with the biological stability within the water distribution network and has garnered considerable attention in the environmental engineering field in recent years. Water samples were collected from the effluent of each unit in CCLAWTP once monthly during December 2008 to November 2009. Items of water quality related to carbon concentration levels, including AOC, total organic carbon, dissolved organic carbon, UV₂₅₄, and specific ultraviolent absorbance were analyzed. Analytical results demonstrate that the average AOC concentration in raw water was 83.61 ??g/L and reduced in freshwater was controlled at an average of 50 ??g/L after an advanced treatment system of roughly 54% of AOC was removed in compliance with treatment plant standards. If AOC concentrations in freshwater can be reduced, study results can provide a direction for improving water treatment capabilities.     

青海省西宁市与天峻县大气中得克隆与十溴联苯醚的水平与来源

十溴联苯醚(BDE-209)与得克隆(DP)是两种常见的添加型卤代阻燃剂,被广泛应用于各种电子产品中.由于其普遍存在于多种环境介质中,现已成为一种广泛存在的污染物,可能会对人体及生态系统产生潜在的危害.本研究测定了青海省西宁市与海西蒙古族藏族自治州天峻县夏、冬两季大气中BDE-209与DP的水平.结果表明,青海省西宁市夏、冬两季大气中BDE-209的平均水平分别为370 pg·m-3、470 pg·m-3,天峻县为220 pg·m-3、390 pg·m-3,与其他城市和地区相比,属于水平较高的地区.而西宁市大气中DP的平均水平为0.85 pg·m-3、0.25 pg·m-3,天峻县为0.24 pg·m-3、0.16 pg·m-3,西宁市水平高于天峻县,夏季水平高于冬季,与其他地区相比,青海省DP整体水平较低.西宁市与天峻县DP的同分异构体中,anti-DP所占比例分别是0.66±0.04与0.68±0.06,在时间与时空上的变化均不明显.青海省BDE-209与DP呈现弱的负相关性,说明两种污染物在青海省可能没有相同的本地源.     

Top-runner incentive scheme in China: a theoretical and empirical study for industrial pollution control

Environmental Science and Pollution Research - Pollution control policies have achieved remarkable results in China. However, industrial firms still lack enthusiasm for technological innovation to...     

Report: transboundary hazardous waste management. part II: performance auditing of treatment facilities in importing countries.

Before implementing the self-monitoring model programme of the Basel Convention in the Asia, Taiwan has conducted a comprehensive 4-year follow-up project to visit the governmental authorities and waste-disposal facilities in the countries that import waste from Taiwan. A total of nine treatment facilities, six of which are reported in this paper, and the five countries where the plants are located were visited in 2001-2002. France, Belgium and Finland primarily handled polychlorinated biphenyl capacitors, steel mill dust and metal waste. The United States accepted metal sludge, mainly electroplating sludge, from Taiwan. Waste printed circuit boards, waste wires and cables, and a mixture of waste metals and electronics were the major items exported to China. Relatively speaking, most treatment plants for hazardous waste paid close attention to environmental management, such as pollution control and monitoring, site zoning, system management regarding occupational safety and hygiene, data management, permits application, and image promotion. Under the tight restrictions formulated by the central environment agency, waste treatment plants in China managed the environmental issues seriously. For example, one of the treatment plants had ISO 14001 certification. It is believed that with continuous implementation of regulations, more improvement is foreseeable. Meanwhile, Taiwan and China should also continuously enhance their collaboration regarding the transboundary management of hazardous waste.     

EXAFS study of adsorbed Cu(II) on fly ashes with different residual carbon contents.

This work studied the speciation of copper species adsorbed onto the surface of fly ash using X-ray absorption spectroscopy (XAS). Experimental results verified that the chemical bond between Cu(II) and the surface of the fly ash was Cu-O. The data set was optimally fitted into the two atomic shells: the first shell containing O atoms and the second shell containing Cu atoms. The extended X-ray absorption fine structure (EXAFS) data also show that, in the first shell, about 2.03-2.41 nearest oxygen atoms surround the center Cu atom with a Cu-O bond distance of 1.96-1.99 A. The results further demonstrated that the bond distance slightly increased with an increasing carbon content of the fly ash.     

Surface chemistry of activated carbons and its relevance for effects of relative humidity on adsorption of chlorinated organic vapors

The effects of relative humidity (RH) on the adsorption of methylene chloride (METH) and 1,1,1-trichloroethane (TCEA) on two commercial activated carbons, made from bituminous coal (carbon BPL) and coconut shell (carbon PCB), were studied. Three levels of RH were tested by tracking the breakthrough curves of each adsorbate eluted from a fixed-bed adsorption column. Adsorption capacities for these adsorbates were decreased with increase of RH. The magnitude of the effect of water vapor on adsorption is greater for carbon BPL and METH than for carbon PCB and TCEA. The results of the effect of water vapor on the adsorption capacity observed in this study were further examined based on the chemical characterization of activated carbons and the fundamental physical differences between the adsorbates.     

Prenatal diagnosis of de novo distal 11q deletion associated with sonographic findings of unilateral duplex renal system,pyelectasis and orofacial clefts

In utero diagnosis of de novo distal 11q deletion associated with renal and orofacial malformations has not been previously described. We present a 35-year-old pregnant woman with prenatal sonographic findings of a unilateral duplex renal system, pyelectasis and orofacial clefts at 20 weeks' gestation. Both genetic amniocentesis and postnatal cytogenetic analysis revealed de novo 46,XX,del(11)(q23). After birth, the fetus manifested a dysmorphic phenotype correlated with del(11q) syndrome. Genetic marker analysis showed a paternally derived distal deletion of chromosome 11q and a breakpoint centromeric to D11S1341. The present case represents the earliest prenatal diagnosis of a duplex renal system, pyelectasis and an additional feature of orofacial clefts associated with distal 11q deletion. Prenatal sonographic detection of a duplex renal system, pyelectasis and orofacial clefts should warrant a careful assessment of fetal anatomy and prompt cytogenetic analysis looking for chromosomal aberrations. Copyright © 2001 John Wiley & Sons, Ltd.     

城市污染治理市场化的可行性研究

分析了国家有关污染治理市场化的政策和法规、国内外的成功经验以及重庆具备有利条件，据测算每个家庭月增加支出污水和垃圾处理费14.35-29.84元。对城市居民的生活质量不会造成明显的负 面影响，表明城市污染治理走市场化之路是可行的。     

带轮毂直齿圆柱齿轮精锻的变形分析

此文对空心坯料精锻带轮毂直齿圆柱齿轮工艺进行了模拟实验,并以座标网格法着重对精锻终了阶段进行了变形分析,获得了金属流动规律,提出了对制订精锻工艺有参数价值的结论。