Effects of polydiallyldimethyl ammonium chloride coagulant on formation of chlorinated by products in drinking water.

The objectives of this research work was to evaluate the reduction of THM precursors by cationic p-DADMAC and determine the correlations between the chlorine demand and trihalomethane formation in the presence of electrolyte solutions and ambient light. The chlorine demand was found to be significantly reduced provided that the H2SO4 electrolyte was fed to the sample solutions. The amount of CHCl3 formation was also decreased when the Na2SO4 electrolyte was introduced in spite of the levels of light intensity. The p-DADMAC can not only effectively remove the turbidity but also reduce the formation of CHCl3. The optimum dosage of p-DADMAC for reducing the turbidity, TOC and CHCl3 in the humic acid and source water samples was determined and depended upon the nature of organics.     

Mass-size distributions of particulate sulfate, nitrate, and ammonium in a particulate matter nonattainment region in southern Taiwan

Concentrations and distributions of three major water-soluble ion species (sulfate, nitrate, and ammonium) contained in ambient particles were measured at three sampling sites in the Kao-ping ambient air quality basin, Taiwan. Ambient particulate matter (PM) samples were collected in a Micro-orifice Uniform Deposit Impactor from February to July 2003 and were analyzed for water-soluble ion species with an ion chromatograph. The PM1/ PM2.5 and PM1/PM10 concentration ratios at the emission source site were 0.73 and 0.53 and were higher than those (0.68 and 0.48) at the background site because there are more combustion sources (i.e., industrial boilers and traffic) around the emission source site. Mass-size distributions of PM NO3- were found in both the fine and coarse modes. SO4(2-)and NH4+ were found in the fine particle mode (PM2.5), with significant fractions of submicron particles (PM1). The source site had higher PM1/PM10(79, 42, and 90%) and PM1/PM2.5 concentration ratios (90, 58, and 93%) for the three major inorganic secondary aerosol components (SO4(2-), NO3-, and NH4+) than the receptor site (65, 27, and 65% for PM1/PM10, 69, 51, and 70% for PM1/PM2.5. Results obtained in this study indicate that the PM1 (submicron aerosol particles) fraction plays an important role in the ambient atmosphere at both emission source and receptor sites. Further studies regarding the origin and formation of ambient secondary aerosols are planned.     

Management and performance of Taiwan's waste recycling fund

Taiwan's resource recycling program was formally established in 1989, starting with the mandatory recycling of polyethylene terephthalate bottles. The number of mandatory regulated materials was extended to 8 categories with 27 items by 2002. Because of false data reporting, financial scandal, lack of transparency of the system, and the demand from parliament, the recycling policy has gradually changed from entirely privatized to being nationalized. Currently, the structure is built on six main bodies: fund management committee, consumers, industries responsible, recyclers, fee reviewing committee, and auditing agents. The industries that are responsible submit a fee, which is set by the fee reviewing committee, to the waste recycling fund (WRF), which is operated by the fund management committee. The auditing agents routinely check the responsible industries by documentation review as well as on-site counting to ensure that the fee is correctly submitted. The WRF provides initiatives to collect and dispose of the end-of-life products. The fund is split into a trust fund and a nonbusiness fund to deal with the collection, disposal, and treatment of the listed materials. The latter deals with the supporting works and ensures that the system runs effectively. The ratio of trust fund to nonbusiness fund is 80-20%. It is no doubt that the current practice achieves some improvements. Household waste has been reduced by 22%. And, most importantly, the benefit-to-cost ratio was as high as 1.24. However, similar to other state-owned systems, the resource recycling program has been criticized for false reporting from the responsible industries, a rigid system, and complicated procedures. To build a sustainable enterprise, the recycling program should be privatized as the recycling market and operating procedures are well established and fully mature.     

Photochemical production of ozone and control strategy for Southern Taiwan

An observation-based method (OBM) is developed to evaluate the ozone (O₃) production efficiency (O₃ molecules produced per NO_x molecule consumed) and O₃ production rate (P(O₃)) during a field campaign in southern Taiwan. The method can also provide an estimate of the concentration of OH. A key step in the method is to use observed concentrations of two aromatic hydrocarbons, namely ethylbenzene and m,p-xylene, to estimate the degree of photochemical processing and amounts of photochemically consumed NO_x and NMHCs by OH. In addition, total oxidant (O₃+NO₂) instead of O₃ itself turns out to be very useful for representing ozone production in the OBM approach. The average O₃ production efficiency during the field campaign in Fall (2003) is found to be about 10.2±3.9. The relationship of P(O₃) with NO_x is examined and compared with a one-dimensional (1D) photochemical model. Values of P(O₃) derived from the OBM are slightly lower than those calculated in the 1D model. However, OH concentrations estimated by the OBM are about a factor of 2 lower than the 1D model. Fresh emissions, which affect the degree of photochemical processing appear to be a major cause of the underestimate. We have developed a three-dimensional (3D) OBM O₃ production diagram that resembles the EKMA ozone isopleth diagram to study the relationship of the total oxidant versus O₃ precursors. The 3D OBM O₃ production diagram suggests that reducing emissions of NMHCs are more effective in controlling O₃ than reducing NO_x. However, significant uncertainties remain in the OBM, and considerable more work is required to minimize these uncertainties before a definitive control strategy can be reached. The observation-based approach provides a good alternative to measuring peroxy radicals for evaluating the production of O₃ and formulating O₃ control strategy in urban and suburban environments.     

Vertical distribution of polycyclic aromatic hydrocarbons in atmospheric boundary layer of Beijing in winter

Air samples were collected using active samplers at various heights of 8, 15, 32, 47, 65, 80, 102, 120, 140, 160, 180, 200, 240, 280 and 320 m on a meteorological tower in an urban area of Beijing in two campaigns in winter 2006. Altitudinal distributions of polycyclic aromatic hydrocarbons (PAHs) in atmospheric boundary layer of Beijing in winter season were investigated. Meteorological conditions during the studied period were characterized by online measurements of four meteorological parameters as well as trajectory calculation. The mean total concentrations of 15 PAHs except naphthalene of gaseous and particulate phase were 667±450 and 331±144 ng m⁻³ in January and 61±19 and 29±6 ng m⁻³ in March, respectively. Domestic coal combustion and vehicle emission were the dominant PAH sources in winter. Although the composition profiles derived from the two campaigns were similar, the concentrations were different by one order of magnitude. The higher concentrations in January were partly caused by higher emission due to colder weather than March. Moreover, weak wind, passing through the city center before the sampling site, picked up more contaminants on the way and provided unfavorable dispersion condition in January. For both campaigns, PAH concentrations decreased with heights because of ground-level emission and unfavorable dispersion conditions in winter. The concentration ratio of PAHs in gas versus solid phases was temperature dependent and negatively correlated to their octanol–air partition coefficients.     

强力霉素生产废水资源化技术研究

根据强力霉素生产废水的特殊性,选用三烷基胺为络合剂、正辛醇和磺化煤油为稀释剂、氢氧化钠为反萃取剂,进行萃取-反萃取实验研究.确定了最佳的工艺条件.结果表明,通过三级萃取后,磺基水杨酸(SSA)、对甲基苯磺酸(PTSA)、COD和BOD5去除率分别达到99.8%、95.4%、92.8%和77.4%,一次反萃取率接近100%,并且萃取剂可以循环使用.采用该工艺不但有明显的环境效益,而且还可以回收磺酸类原料资源.具有良好的经济效益.     

Numerical study of the effect of ventilation pattern on coarse, fine, and very fine particulate matter removal in partitioned indoor environment

An indoor size-dependent particulate matter (PM) transport approach is developed to investigate coarse PM (PM10), fine PM (PM2.5), and very fine PM (PM1) removal behaviors in a ventilated partitioned indoor environment. The approach adopts the Eulerian large eddy simulation of turbulent flow and the Lagrangian particle trajectory tracking to solve the continuous airflow phase and the discrete particle phase, respectively. Model verification, including sensitivity tests of grid resolution and particle numbers, is conducted by comparison with the full-size experiments conducted previously. Good agreement with the measured mass concentrations is found. Numerical scenario simulations of the effect of ventilation patterns on PM removal are performed by using three common ventilation patterns (piston displacement, mixing, and cross-flow displacement ventilation) with a measured indoor PM10 profile in the Taipei metropolis as the initial condition. The temporal variations of suspended PM10, PM2.5, and PM1 mass concentrations and particle removal mechanisms are discussed. The simulated results show that for all the of the three ventilation patterns, PM2.5 and PM1 are much more difficult to remove than PM10. From the purpose of health protection for indoor occupants, it is not enough to only use the PM10 level as the indoor PM index. Indoor PM2.5 and PM1 levels should be also considered. Cross-flow displacement ventilation is more effective to remove all PM10, PM2.5, and PM1 than the other ventilation patterns. Displacement ventilation would result in more escaped particles and less deposited particles than mixing ventilation.     

EDTA-assisted phytoextraction of lead from lead-contaminated soils by Echinochloa crusgalli var. frumentacea

The herbaceous plant Echinochloa crusgalli var. frumentacea is highly resistant to a wide range of heavy metal concentrations. In this study we tested the phytoextraction capacity of E. crusgalli var. frumentacea. Specifically, we compared the effect of EDTA on lead (Pb) accumulation in two groups of plants: those sown in lead contaminated soil and those transplanted to the contaminated soil as seedlings. The result of the time development of the Pb concentrations in the plants in the seedling and seed groups shows that for the seedling group, the effect of adding EDTA to the Pb-contaminated soil was even more pronounced in the shoots than the roots, which showed Pb concentrations 32-fold higher. Compared to the seedling group, the Pb concentrations in the roots of plants in the seed group were approximately 5 times higher in controls and 2 to 10 times higher in the presence of EDTA. Collectively, these results might be considered that EDTA elevates the bioavailability of Pb in soil and this native species is particularly suited to use in Pb phytoextraction.     

湖南省隆回县金银花产业现状及发展对策

介绍了隆回县金银花资源培育和加工利用现状,综合分析了金银花的综合价值和发展前景,针对当前金银花产业发展中存在的经营方式落后、加工粗放、销售不畅等问题,提出了金银花产业发展的对策.     

Seasonal variation of nonylphenol concentrations and fluxes with influence of flooding in the Daliao River Estuary, China

Nonylphenol is an endocrine disruptor with harmful effects including feminization and carcinogenesis on various organisms. This study aims to investigate the distribution and ecological risks of nonylphenol in the Daliao River Estuary, China. Nonylphenol, together with other phenolic endocrine disruptors (bisphenol A, 4-t-butylphenol, 4-t-octylphenol, and 2,4-dichlorophenol), was detected in surface water and sediment on three cruises in May 2009, June 2010, and August 2010, respectively. A large flooding occurred during our sampling campaign in August and its effect on nonylphenol concentrations and fluxes in the estuary was therefore evaluated. The results showed that nonylphenol with a concentration range between 83.6–777 ng l^?1 and 1.5–456 ng?g^?1 dw in surface water and sediment was the most abundant among the phenolic compounds, accounting for 59.1–81.0 and 79.9–92.1 % of the total phenolic concentration in surface water and sediment, respectively. The concentrations recorded in May and June were comparable, whereas those in August were considerably higher, mainly due to the flush of flooding. The flooding also caused a 50 times increase in nonylphenol flux from the estuary into the adjacent Bohai Sea. Nonylphenol concentrations in the estuary have exceeded the threshold level of undesirable effects with a potential risk of harm to local species, especially benthic organisms.