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161.
河水可溶性有机物与Cu~(2+)络合常数的确定   总被引:3,自引:0,他引:3       下载免费PDF全文
分别采用单配位体、双配位体离散模型与连续分配模型对水体中可溶性有机物与金属铜离子的络合行为进行描述 .单配位体模型的使用中可采用不同拟合手段 ,对拟合结果有一定影响 .单纯以可决系数与误差平方和为判断依据 ,非线性拟合的拟合效果最佳 ,拟合结果为条件稳定常数logk =2 2 6 ,络合容量C =6 70mol·g-1.检测窗口的变化在极大程度上影响络合常数的计算结果 .双配位体模型的非线性拟合结果为logk1=7 2 9、logkn=1 90、C1=0 0 2 3mol·g-1、Cn=13 74 6mol·g-1,与单配位体模型相比没有明显改善 .连续分配模型可用来描述不同络合位饱和度下条件稳定常数的连续变化 ,并从曲线的外推计算出最强络合位的络合常数logkmax=4 71  相似文献   
162.
An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, Cape D‘Aguilar, in Hong Kong. The trace element composition of aerosol particles(TSP and PM10) were measured and analyzed by using the Instrumental Neutron Activation Analysis(INAA) and Inductive Couple Plasma-Mass Spectrometry(ICP-MS) techniques. The results showed that the polluted elements such as: V, Zn, As, Pb, Cd, Sb, I, Se, Bi, with high enrichment factor( E. F) values, are derived from anthropogenic sources ,while Sc, AI, Fe, Mn, Sm, La, Sr are less than 10 in E. F, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V(V^* ) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn^*/V^* and Bi/Al indicate that both TSP and PM10 of La/Sm ratios are mainly related to soil and dust, Mn^*/V^* are probably represent fossil combustion and Bi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis (APCA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime.  相似文献   
163.
分析了高密度城市道路交通噪声分布的特点,从噪声接受点评价的观点出发,以香港地区为例,研究不同建筑形态道路交通噪声的典型分布。基于方法是采用简化的DoT模型计算道路交通噪声,以基于GIS的道路交通噪声评价预测系统为工具计算不同建筑类型各单元的噪声级,再统计出各型建筑的噪声分布。通过Kolmogorov-Smirnov检验证实这些分布来自于不同总体,具有显著的差异。将上述计算结果运用于香港新界西北地区道路交通噪声的战略环境评价。  相似文献   
164.
Both cooperation and conflict between the sexes are commonplace in monogamous mating systems. However, little is known about how cooperation and competition varies seasonally in monogamous species that maintain permanent territories. We presented territorial pairs of male and female New Zealand robins (Petroica australis) with a large supply of insect prey at monthly intervals for 2 years. Behavioural observations after food presentation were then made to quantify seasonal and sexual differences in aggressive interactions over prey, prey acquisition rates, mate provisioning, offspring provisioning, selfish food hoarding and cache retrieval. Data were used to evaluate sex-specific behavioural strategies of mediating competition for food. Results showed that males aggressively excluded females from experimental food sources year-round. Females only accessed food sources when males left them unattended. Consequently, females acquired fewer prey than males. After controlling for differences in prey acquisition, both sexes consumed similar amounts of prey in the non-breeding season. Even though males aggressively excluded females from accessing food sources directly, males fed large amounts of prey to females during the breeding season. Both sexes provisioned young at similar rates. Males cached less prey than females in the breeding season but more prey than females in the non-breeding season. Females showed similar caching intensities year-round. Although males tried to defend their hoards, females frequently retrieved male-made caches. Overall, results showed that although New Zealand robins cooperate to raise offspring during the breeding season, conflict between the sexes occurs year-round. Males and females display different behavioural strategies to gain access to experimental food sources, which appear to lessen male–female competition for food and evenly distribute food resources between the sexes.  相似文献   
165.
Local residents may have different views on disaster‐response modes depending on their cultural and socioeconomic background. The purpose of this study was to examine Taiwan residents' opinions on the Incident Command System (ICS). We performed a structured survey through face‐to‐face interviews in mudslide‐affected communities. Quantitative analysis showed that the residents exhibited a clear preference for the ICS core‐principle attributes of ‘integrated communications’, ‘transfer of command’ and ‘modular organisation’. By contrast, the residents tended towards a non‐ICS approach for ‘incident action plan’ and ‘manageable span of control’. Qualitative analysis revealed an uncertain attitude towards ‘transfer of command’ and ‘incident action plan’. Community acceptance is important in the promotion of the ICS. A better understanding of residents' preferences should be acquired through a broader community survey, allowing us to understand perspectives on the ICS among different societies and facilitate implementation of the ICS at the basic community level.  相似文献   
166.
This article demonstrates why it is necessary to have the restoration of marine coastal ecosystem health as a new goal for integrated catchment management in the coastal area of Tolo Harbor. The present goal of integrated catchment management (ICM) in the Tolo Harbor is based on water quality objectives. The performance of the ICM plan, the Tolo Harbor Action Plan (THAP), was evaluated using marine coastal ecosystem health indicators including both stress and response indicators. Since the implementation of THAP in 1988, some significant reductions in pollution loading have been observed: reduction of 83% of biological oxygen demand load and 82% of total nitrogen between 1988 and 1999. There has also been an improvement in the health of Tolo Harbor’s marine coastal ecosystem as evidenced by trends in physical, chemical, and biological indicators, although reverse fluctuations in some periods exist. However, such improvement can only be considered as the first sign of complete ecosystem health restoration, because ecosystem health covers not only physical, chemical, and biological aspects of an ecosystem, but also ecosystem service functions. The findings support the need to take the restoration and protection of marine coastal ecosystem health as a new goal rather than using water quality objectives. Steps necessary to further improve Tolo Harbor’s marine coastal ecosystem health are also discussed.  相似文献   
167.
Development of a Marine Sediment Pollution Index.   总被引:5,自引:0,他引:5  
To facilitate translation of the state of marine sediment quality for public information, a pollution index was developed from the results of a routine monitoring program. Principal component analysis (PCA) of 24 variables at 64 monitoring stations from 1987 to 1997 was carried out to identify the most important parameters that were applied in the index formulation. Of the 24 variables, six (Cr, Cu, Ni, chemical oxygen demand, Zn, Mn) were selected on the basis of their high PCA loadings. The derived Marine Sediment Pollution Index, rating from 0 to 100, reflected the general trend in the monitoring areas. The index was also found to have a significant negative correlation (P < 0.05) with the benthic species diversity and toxicity of the sediment, indicating its usefulness in reflecting marine sediment quality. The application of PCA to identify important variables from a monitoring program would reduce sampling resources, as parameters that did not show significant spatial or temporal variations could be analyzed in a lesser frequency than those that were identified to be more important from the results of PCA.  相似文献   
168.
An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 atcoastal region, Cape D'Aguilar, in Hong Kong. The trace element composition of aerosol particles(TSP and PM10)were measured and analyzed by using the Instrumental Neutron Activation Analysis (INAA) and Inductive CouplePlasma-Mass Spectrometry(ICP-MS) techniques. The results showed that the polluted elements such as: V, Zn,As, Pb, Cd, Sb, I, Se, Bi, with high enrichment factor( E. F) values, are derived from anthropogenic sources ,while Sc, Al, Fe, Mn, Sm, La, Sr are less than 10 in E. F, these elements are related the crust and soil. Theconcentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the Vor noncrustal V(V* ) present summer high and winter low, this phenomenon might be explained by local or regionaloil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn* /V* and Bi/Al indicate that both TSPand PM10 of La/Sm ratios are mainly related to soil and dust, Mn*/V* are probably represent fossil combustion andBi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimaxrotation factor analysis for trace elements was performed. By means of the absolute principal component analysis(APCA) and multiple regression, the contribution of trace elements to possible sources and overall means of traceelements were estimated. The results showed that the present station is impacted by the anthropogenic species,although the quantities are different during the summertime and wintertime.  相似文献   
169.
Different types of food wastes, e.g., meats, bones, cereals, fruits, and vegetables, were collected from hotels in Hong Kong, mixed in different ratio, and processed into feed pellets (food wastes (FWs) A, B, and C) for feeding trials in aquaculture species. Grass carp fed with cereal-dominant feed (FW A) showed the best growth (in terms of specific growth rate, relative weight gain, and protein efficiency ratio), among all food waste feeds. However, the growth rates of food waste groups especially the meat product-contained feeds (FW B and FW C) were lower than the commercial feed, Jinfeng® 613 formulation (control). The results indicated that grass carp utilized plant proteins better than animal proteins and preferred carbohydrate as a major energy source than lipid. The high-lipid content in feed containing meat products was also a possible reason for hindering growth and resulted high body lipid. It is suggested that lipid should be removed in the preparation of food waste feed or further investigations by implementing supplements, e.g., enzymes in feed to enhance lipid or protein utilization by fish. This utilization of food waste could be an effective and practical way to deal with these wastes in this densely populated city.  相似文献   
170.
Xia C  Lam JC  Wu X  Sun L  Xie Z  Lam PK 《Chemosphere》2011,82(11):1662-1668
This study reports concentrations of hexabromocyclododecanes (HBCDs) in two species of marine fish, large yellow croaker (Pseudosciaenacrocea) and silver pomfret (Pampusargenteus) (n = 46), from nine Chinese coastal cities (Dalian, Tianjin, Qingdao, Shanghai, Zhoushan, Wenzhou, Fuzhou, Quanzhou and Xiamen). HBCDs were detectable in all samples analyzed, indicating ubiquitous contamination of these compounds in the Chinese coastal environment. The average total HBCD concentration was 3.7 ng g−1 lipid weight (range: 0.57-10.1 ng g−1 lipid weight), which is relatively lower than other regions of the world, especially Europe, where HBCDs are intensively used. Among the three individual HBCD isomers (α-, β- and γ-HBCD) in all fish samples, the α-isomer showed a remarkable predominance (from 87.5% to 100% of total contribution), indicating its higher bioaccumulative potential. Geographically, the highest HBCD level present in fish was found in Dalian in northern China, and the lowest occurred in Wenzhou. Estimated daily intakes of HBCDs via fish consumption for the Chinese population were 0.004-1.00 ng kg body weight−1 d−1. These exposure levels were much lower than the effect levels.  相似文献   
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