聚合物驱采出水中聚丙烯酰胺的微生物联合降解作用研究

通过对2株细菌的培养降解实验研究聚丙烯酰胺(hydrolyzed polyacrylamide,HPAM)降解菌对水环境下聚丙烯酰胺的降解作用,讨论协同降解机理。2株降解聚丙烯酰胺的菌株假单胞菌CJ419、枯草芽孢杆菌FA16在初始30℃废水样品上培养,定期测量细菌生物量和HPAM降解率。培养30 d后CJ419和FA16对聚合物的降解率最大值分别达到30.4%和25%,而以1∶1比例的混合菌降解率最大值达到80.3%。对2株菌胞外各组分研究表明:混合菌降解HPAM的机理主要由胞外降解酶系水解聚合物侧链基团导致HPAM降解为小分子物质,同时生长过程中降解菌还会释放非蛋白还原性物质引发氧化反应共同参与HPAM降解。     

Size mass distribution of water-soluble ionic species and gas conversion to sulfate and nitrate in particulate matter in southern Taiwan

A Micro-Orifice Uniform Deposition Impactor (MOUDI) and a Nano-MOUDI were employed to determine the size-segregated mass distributions of ambient particulate matter (PM) and water-soluble ionic species for particulate constituents. In addition, gas precursors, including HCl, HONO, HNO₃, SO₂, and NH₃ gases, were analyzed by an annular denuder system. PM size mass distribution, mass concentration, and ionic species concentration were measured during the day and at night during episode and non-episode periods in winter and summer. Average total suspended particle (TSP) concentrations during episode days in winter were as high as 153?±?33 μg/m³, and PM mass concentrations in summer were as low as one-third of that in winter. Generally, PM concentration at night was higher than that in the daytime in southern Taiwan during the sampling periods. In winter during the episode periods, the size-segregated mass distribution of PM mass concentration was mostly in the 0.32–3.2-μm range, and the PM concentration increased significantly in the range of 0.32–3.2 μm at night. Ammonium, nitrate, and sulfate were the dominant water-soluble ionic species in PM, contributing 34–48 % of TSP mass. High concentrations of ammonia (12.9–49 μg/m³) and SO₂ (2.6–27 μg/m³) were observed in the gas precursors. The conversion ratio was high in the PM size range of 0.18–3.2 μm both during the day and at night in winter, and the conversion ratio of episode days was 20 % higher than that of non-episode days. The conversion factor was high for both nitrogen and sulfur species at nighttime, especially on episode days.     

The influence of sampling protocol on nonmethane hydrocarbon mixing ratios

The effect of sampling protocol on ambient air hydrocarbon mixing ratios was examined on eight sampling days in Los Angeles during 2007 and 2008. Four protocols, which were based on previously published multi-city urban hydrocarbon studies in the United States, were compared and differences were quantified. Whole air canister samples were collected and analyzed for nonmethane hydrocarbons (NMHCs). Differing sampling protocols resulted in large differences in mixing ratios, up to an order of magnitude, for certain NMHCs on the same sampling day. However, the magnitude of the variability between NMHC levels obtained by the four protocols was not consistent throughout the eight sampling days. It was found that sampling time, followed by sampling location, had the greatest influence on the magnitude of the mixing ratio. Ratios between hydrocarbons, often used in urban studies to gain information on emission sources, also varied depending on the protocol used. Comparison of absolute NMHC mixing ratios collected in urban environments using differing sampling protocols should be made with care.     

Incidence of polybrominated diphenyl ethers in central air conditioner filter dust from a new office building

This study examined polybrominated diphenyl ethers (PBDEs) in central air conditioner filter (CACF) dust from a new office building in Shenzhen, China. Human exposure to PBDE via dust inhalation and ingestion were also estimated. PBDEs level in CACF dust was lower than those in the other countries and regions. Approximately 0.671 pg/kg bw/day PM_2.5 (Particulate Matter up to 2.5 μm in size) bounded Σ₁₅PBDEs can be inhaled deep into the lungs and 4.123 pg/kg bw/day PM₁₀ (Particulate Matter up to 10 μm in size) bounded Σ₁₅PBDEs tend to be deposited in the upper parts of the respiratory system. The average total intake of Σ₁₅PBDEs via dust inhalation and ingestion for adults reached ∼141 pg/kg bw/day in this building. This value was far below the reference dose (RfD) recommended by United States Environmental Protection Agency. Human exposure to PBDEs via dust inhalation and ingestion in the new building is less than the old ones.     

Characteristics of springtime profiles and sources of ozone in the low troposphere over northern Taiwan

To quantify the possible sources of the high ambient ozone concentration in the low troposphere over Taiwan, ozone sounding data from a two-year intensive field measurement program conducted in April and early May of 2004 and 2005 in northern Taiwan has been examined. We found that the vertical ozone distributions and occurrence of enhanced ozone in the lower troposphere (below 6 km) mainly resulted from (1)Type NE: the long-range transport of ozone controlled by the prevailing northeasterly winds below 2 km, (2)Type LO: the local photochemical ozone production process, and (3)Type SW: the strong southwest/westerly winds aloft (2–6 km). In the boundary layer (BL), where Asian continental outflow prevails, the average profile for type NE is characterized by a peak ozone concentration of nearly 65 ppb at about 1500 m altitude. For type LO, high ozone concentration with an average ozone concentration greater than 80 ppb was also found in the BL in the case of stagnant atmospheric and sunny weather conditions dominated. For type SW, significant ozone enhancement with average ozone concentration of 70–85 ppb was found at around 4 km altitude. It is about 10 ppb greater than that of the types NE and LO at the same troposphere layer owing to the contribution of the biomass burning over Indochina. Due to Taiwan's unique geographic location, the complex interaction of these ozone features in the BL and aloft, especially features associated with northeasterly and south/southwesterly winds, have resulted in complex characteristics of ozone distributions in the lower troposphere over northern Taiwan.     

氯甲烷与偶氮染料混合废水的超声脱色

使用40 kHz超声(US)脱色氯甲烷(包括CCl4、CHCl3和CH2Cl2)与偶氮染料(包括甲基橙与铬黑T)混合模拟废水,考察了氯甲烷初始浓度对偶氮染料超声脱色和TOC去除的影响.结果表明:偶氮染料的单独超声脱色速率很慢;而在CCl4与CHCl3存在时超声能使偶氮染料短时间内脱色至无色,但对其TOC的超声去除促进作...     

The effect of aviation safety education on passenger cabin safety awareness

This paper examines the effect of aviation safety education on passenger cabin safety awareness in knowledge, attitude, and behavior (KAB). The educational value of KAB has been addressed in various fields such as AIDS prevention and campus safety. KAB has been applied in aviation safety related areas, especially in training, such as crew resource management training, pilot training, and mechanic training. However, KAB has not been implemented in aviation passenger education in cabin safety. This paper uses the construct of “aviation safety education”, which is intended to influence airline passenger knowledge of, attitude toward, and behavior about cabin safety awareness. Passenger surveys were done at two Taiwan airports. The results show that aviation safety education positively affects airline passenger cabin safety knowledge, attitude, and behavior. We recommend safety education that involves accurate instruction about emergency equipment procedures, situational awareness, emergency responses, and relevant cabin-safety regulations.Our findings indicated that an increase in cabin safety knowledge positively affected airline passenger behavior, which supported knowledge–behavior consistency. We also found that a positive attitude toward cabin safety positively affected airline passenger behavior, which supported attitude–behavior consistency. The hypothesis that cabin safety knowledge positively affected passenger attitude – knowledge–attitude consistency was not supported.     

基于置信区间的风暴潮灾害损失预警及对策研究

在运用因子分析法和熵值法对中国沿海11个省、自治区、直辖市进行风暴潮风险区划的基础上,运用置信区间法计算出各个区划内不同风暴潮等级对应的风暴潮经济损失、养殖业损失的置信区间。分析风暴潮置信区间结果,旨在有助于在增水等自然数据情况合理准确的预测基础上,对各个风险区划进行风险预警。并从防灾意识与产业结构调整两个方面提出了对策建议,力求使风暴潮造成的收入等经济损失最小化、保障沿海地区经济与社会的安全。     

IS IT REALISTIC TO DEFINE A 100-YEAR DROUGHT FOR WATER MANAGEMENT?1

ABSTRACT: The concept of recurrence interval has been used for years in engineering designs. Can the same concept be applied to the drought analysis? This paper uses the plotting position method to define drought of various recurrence intervals based on stream-flow data. The method of truncation level was applied to the same data to examine the defined drought. Based on the method of truncation level, drought duration and its corresponding flow deficit were investigated. Eighteen flow gage stations from the Scioto River Basin in Ohio were selected for the study. The results show that flows of 100-year droughts using the plotting position method are practically nil. On the other hand, flows of droughts using the truncation method are gradually decreasing with an increase in truncation level, where flows of 95 percent are approximately equal to those of two-year droughts defined by the plotting position. It is also shown that there is a strung correlation between drought duration and deficit.