[show abstract][hide abstract] ABSTRACT: To understand concentrations of perfluorinated compounds (PFCs) in aquatic products, and risks to human health, concentrations of 12 PFCs were measured in edible tissues of aquatic products collected from Tianjin, China, a typical industrial area on the western Bohai Sea. Perfluorooctane sulfonate (PFOS) was the predominant PFC. Concentrations of PFOS in aquatic products from Tianjin Binhai New Area (TBNA) ranged from
Human and Ecological Risk Assessment 11/2011; 17(6):1279-1291. · 1.29 Impact Factor
[show abstract][hide abstract] ABSTRACT: Concentrations of metals and arsenic in farmland soils along the Yanghe River, upstream of Guanting Reservoir, were evaluated using fuzzy comprehensive assessment (FCA). FCA is an emerging methodology for assessing environmental status based on fuzzy logic which can model linguistic data and represent chaotic conditions. The ratio of concentrations of metals and arsenic (As) in surface soils of farmland along the Yanghe River to the corresponding reference values decreased in the order Cd>Zn>Cr>Ni>Pb>Cu>As. Based on the FCA, 86% of surface soils along the Yanghe River were classified as grade C, which is suitable for forestry with a greater absorption capacity, suggesting that most farmland along the Yanghe River has to be abandoned as farmland. In order to improve the quality of soil along the Yanghe River and avoid degeneration of water quality in the river and the Guanting Reservoir, remediation of farmland soils along the river is suggested.
Chemistry and Ecology 10/2011; 27(5):415-426. · 1.07 Impact Factor
[show abstract][hide abstract] ABSTRACT: Concentrations of perfluorooctanesulfonate (PFOS), perfluorooctanoic acid (PFOA) and other perfluorinated compounds (PFCs) were measured in water and sediment from coastal Bohai Bay and surrounding rivers flowing into the bay. Of the 15 PFCs measured, PFOS and PFOA were detected with the greatest frequency. Concentrations in water ranged from<0.2 to 31 ng·L−1 and<1.0 to 82 ng·L−1 for PFOS and PFOA, respectively. Concentrations of PFOS and PFOA in sediments ranged from<0.1 to 2.0 ng·g−1 dw and<0.1 to 0.5 ng·g−1 dw, respectively. Concentrations of PFCs in Bohai Bay were less than those observed in other areas in Asia, but greater concentrations of ∑PFCs were observed in the Dalin River with concentrations increasing from upstream to downstream, and the greatest concentrations in sediment were observed in tidal flats. The ratio of ∑PFCs in sediment and water indicated that sediment could serve as a significant sink for PFUnA.
Chemistry and Ecology 04/2011; 27(2):165-176. · 1.07 Impact Factor
[show abstract][hide abstract] ABSTRACT: Based on laser crystals, the testing principle of fluorescence lifetime on mus is introduced and a practical device on this principle is designed. The testing system includes exciting source, light path system, detecting circuit, signal disposing circuit and LCD display circuit. Achieved by pulse sampling technique, this device with small size can display the fluorescence lifetime value on LCD directly and reliably, and it measures the fluorescence lifetime of Nd:YAG crystal and doped Nd glass in lab as 240mus or 330mus separately which conforms to the theoretical value very well.
[show abstract][hide abstract] ABSTRACT: A case study of the cancer risk to humans posed by persistent organic pollutants (POPs) in an industrial area of China, which has a long history of contamination from many sources, is presented. Relatively great concentrations of POPs around the chemical industrial parks have the potential to be chronically carcinogenic to local people. Sixteen individual PAHs listed for priory control by the U.S. Environmental Protection Agency (USEPA), metabolites of DDTs, and isomers of HCHs were measured in soils and a human health risk assessment was conducted by use of USEPA exposure models for children and adults, respectively. Geostatistical methods were used to simulate the spatial diffusion of potential carcinogenic risk, and non-parametric Mann-Whitney U and Kruskal-Wallis tests were employed to analyze the impact of point sources on the surrounding area. The mean value of the sum of Excess Lifetime Cancer Risk (Sigma ELCR) exceeded the generally acceptable risk level of 1.0E-06 recommended by the USEPA for
HUMAN AND ECOLOGICAL RISK ASSESSMENT. 01/2010; 16.
[show abstract][hide abstract] ABSTRACT: Tianjin Bin Hai New Area (BHNA) is the third largest economic zone in China. This is an older industrial area that has been developing rapidly but with many historic sources of contamination. The concentrations of 16 individual polycyclic aromatic hydrocarbons (PAHs) listed for priority control by the US EPA were quantified in 105 surface soil samples by the use of gas chromatography mass spectrometry (GC/MS). Multivariate statistical methods were used to characterise the mixtures and make comparisons in the patterns among areas. Concentrations varied among areas, ranging from moderate to relatively high. The coefficients of determination between concentrations of individual PAHs and total concentration of PAH (∑ PAH) increased with the number of rings. The first three factors from the principal component analysis (PCA) explained 81.6% of the total variation, while ten higher molecular weight (HMW) PAHs’ loadings for factor 1 accounted for 51.0%. Based on the patterns of relative loading proportions of individual PAHs calculated by PCA, the primary sources were coal combustion, traffic emissions including gasoline, diesel oil, and the burning of natural gas. The spatial distribution of concentrations of fluorene had a poor spatial autocorrelation in the study area. The sites with the greatest potential risk due to exposure to PAHs were mainly distributed around the chemical industry parks.
Chemistry and Ecology - CHEM ECOL. 01/2010; 26(1):35-48.
[show abstract][hide abstract] ABSTRACT: Concentrations and composition of 16 polycyclic aromatic hydrocarbons (PAHs) listed for prior control by US EPA were detected by analyzing 28 surface soil samples from the chemical industrial areas of Tianjin Binhai New Area with a gas chromatography equipped with mass spectrometry (GC/MS). Relative concentrations of PAH compounds with different benzene rings and principal component analysis were used to identify the possible sources of soil PAHs. The maximum PAH concentration in all the samples was 5,991.7 ng x g(-1), with a mean values of 1,185.0 ng x g(-1). The concentrations of four and five rings PAH components were higher than that of the other PAH components in Tanggu and Hangu chemical industrial areas, and three rings PAH components were major PAHs in Dagang petroleum industrial area. There is significant positive correlation (n = 28, R2 = 0.847, p < 0.01) between PAH concentrations and total organic carbon (TOC) contents in the soil samples. Coal combustion was the dominant source of PAHs in chemical industrial areas, while petroleum volatilization and leakage were main contributors of PAHs in Dagang petroleum industrial area.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 04/2009; 30(4):1166-72.
[show abstract][hide abstract] ABSTRACT: The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined by gas chromatography equipped with a mass spectrometry detector in 105 topsoil samples from an industrial area around Bohai Bay, Tianjin in the North of China. Results demonstrated that concentrations of PAHs in 104 soil samples from this area ranged from 68.7 to 5,590 ng g(-1) dry weight with a mean of summation Sigma16PAHs 814 +/- 813 ng g(-1), which suggests that there exists mid to high levels of PAH contamination. The concentration of summation Sigma16PAHs in one soil sample from Tianjin Port was exceptionally high (48,700 ng g(-1)). Ninety-three of the 105 soil samples were considered to be contaminated with PAHs (>200 ng g(-1)), and 25 were heavily polluted (>1,000 ng g(-1)). The sites with high PAHs concentration are mainly distributed around chemical industry parks and near highways. Two low molecular weight PAHs, naphthalene and phenanthrene, were the dominant components in the soil samples, which accounted for 22.1% and 10.7% of the summation Sigma16PAHs concentration, respectively. According to the observed molecular indices, house heating in winter, straw stalk combustion in open areas after harvest, and petroleum input were common sources of PAHs in this area, while factory discharge and vehicle exhaust were the major sources around chemical industrial parks and near highways. Biological processes were probably another main source of low molecular weight PAHs.
Environmental Monitoring and Assessment 01/2009; 158(1-4):581-92. · 1.59 Impact Factor
[show abstract][hide abstract] ABSTRACT: Topsoil samples (n = 105) were collected to study the distribution of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) residues in the vicinity of chemical industrial parks in Tianjin, China. The occurrence and distribution of target organochlorine pesticides (OCPs) were mapped to identify the spatial variation using Geographical Information System (GIS). In general, the concentrations of OCPs were higher in soils near the industrial parks, even some hotspots showed very high OCP contaminations which could cause ecological risk. The relationships between contaminant concentrations and other factors (land use and soil properties) were discussed. Significant correlations (P < 0.01) between TOC contents and the concentrations of DDTs, alpha-HCH, and beta-HCH indicated the effect of organic carbon on OCP distribution. Soil pH levels had no obvious effect on the OCP distributions. Except for the effects of the industrial parks, the capacities of biodegradation and dissipation of soils under different land uses were the important factors that affected the HCH distribution, but the distribution of DDTs was mainly influenced by the TOC levels. The results of this study can provide some evidences and data on the long term effects of industrial activities in the environment even after the cease of operations for a long time.
Journal of Environmental Quality 01/2009; 38(1):180-7. · 2.35 Impact Factor
[show abstract][hide abstract] ABSTRACT: The current state of concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in China is presented. While products that are known to degrade to either PFOS or PFOA have been used in China, concentrations in environmental media have been reported to be relatively low across China. Greater concentrations of PFOS and PFOA were observed in southern and eastern China than in other areas of China. Concentrations of PFOS and PFOA were relatively great in the Huangpu River, with concentrations of 20.5 ng l and 1590 ng l, respectively. Surface waters of Dongguan and Shanghai were more contaminated by PFOS and PFOA than that of other cities. Dongguan was the only city in China in which PFOS value in surface water exceeded the water quality criterion, while PFOA concentration in Shanghai was 152 ng l. Similar to other contaminants, point-source pollution was also the common pattern of PFOS and PFOA contamination. Concentrations of PFOS in human blood in China were relatively greater in China than other countries, with drinking water contamination given as the most likely source. Concentrations of PFOS in human blood have increased from the 1980s to the 2000s, while such a trend was not observed for PFOA.
Chemistry and Ecology - CHEM ECOL. 01/2009; 25(3):163-177.
[show abstract][hide abstract] ABSTRACT: Based on environmental statistics data from 1993 to 2005, spatial distribution and temporal tendency of the environmental pollution and destruction accidents and their external causes were analyzed by using GIS and non-parametric correlation methods. It was concluded that (1) during the study period, annual environmental pollution accidents was maximally 3001 times in 1994 and minimally 1406 in 2005, while the frequency decreased in general. In addition, water and air accidents occupied the most; (2) environmental pollution and destruction accidents centralized in southeast and middle parts of China, mainly in Hunan, Sichuan, and Guangxi; (3) factors including population, GDP, company number and industrial waste water discharge had positive impacts on frequency of environmental pollution and destruction accidents, while in developed provinces the frequency was only correlated with company number.
Huan jing ke xue= Huanjing kexue / [bian ji, Zhongguo ke xue yuan huan jing ke xue wei yuan hui "Huan jing ke xue" bian ji wei yuan hui.] 10/2008; 29(9):2684-8.
[show abstract][hide abstract] ABSTRACT: Concentrations of organochlorine pesticides (OCPs; dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB)) were investigated in 105 soil samples collected in vicinity of the chemical industrial parks in Tianjin, China. OCP concentrations significantly varied in the study area, high HCH and DDT levels were found close to the chemical industrial parks. The intensity of agricultural activity and distance from the potential OCP emitters have important influences on the OCP residue distributions. Principal component analysis indicates that HCH pollution is a mix of historical technical HCH and current lindane pollution and DDT pollution input is only due to technical DDT sources. The significant correlations of OCP compounds reveal that HCHs, DDTs and HCB could have some similar sources of origin.
Environmental Monitoring and Assessment 07/2008; 152(1-4):259-69. · 1.59 Impact Factor
[show abstract][hide abstract] ABSTRACT: The effects of bicarbonate on the characteristic transformation of fulvic acid (FA) and its subsequent trichloromethane formation potential (TCMFP) were investigated in the process of preozonation. Dissolved organic carbon (DOC) removal rate and the residual aqueous ozone concentration during preozonation were measured with different bicarbonate concentration. The presence of bicarbonate inhibited DOC removal and decreased TCMFP yields in the initial oxidation period. In order to explain these phenomena, the molecular weight (MW) distribution (<5, 5-10, 10-30, and >30 kDa) and corresponding TCMFP were investigated for FA and its subsequent oxidation products. Furthermore, transformation of molecular structure, based on MW distribution, was also characterized with Fourier transform infrared (FTIR) spectrum. Bicarbonate showed different inhibiting effects on TCMFP of organic species with different MW, and more significant TCMFP decrement was observed for the high MW fraction (>30 kDa) than for the low MW fractions. Preozonation led to obvious reduction on DOC and UV254 in most of MW fractions wherever bicarbonate was present or not, demonstrating that ozone contributed to both organics mineralization and structure variation, synchronously. As being indicated from the results of FTIR and gas chromatography-mass spectrometry, the functional groups such as alcohols, epoxides and phenols, the formation of which was promoted with hydroxyl radicals (.OH) and would be remarkably inhibited by bicarbonate, were responsible for the increment of TCM precursor's concentration during ozonation. Results of these studies confirmed low dosage bicarbonate affecting the ozonation pathways, influencing the intermediate species formation and impacting its subsequent TCMFP yields through inhibiting the .OH radicals reactions mainly occurred in high MW fractions.
[show abstract][hide abstract] ABSTRACT: The species transformation and structure variation of fulvic acid (FA) during ozonation were investigated in this study. The
molecular weight (MW) distribution, the species of intermediate products and the variation of polar functional groups were
studied by ultrafiltration, gas chromatography/mass spectrometry (GC/MS) and titration analyses respectively. The average
MW of FA decreased significantly during ozonation. The amount of polar functional groups (carboxylic and phenolic (ph-OH)
groups) per unit DOC (mol/kg C) increased with increasing ozonation time. Furthermore, GC/MS experiments demonstrated the
formation of polar species (e.g., hexadecanoic acid, benzoic acid and octadecanoic alcohol) and less-polar species (e.g.,
aliphatic hydrocarbons and butanedioic acid, bis(2-methylpropyl) ester). Electron spin resonance (ESR) measurements proved
the presence of ·OH radicals in the ozonation system. Based on our experimental results, it appears that the oxidations by
ozone molecule and ·OH radicals were responsible for the transformation of organics (FA and its oxidation products) during
ozonation. These two oxidants showed significant influence on organics transformation and exhibited different mechanisms contributing
to these processes.
Science in China Series B Chemistry 03/2008; 51(4):373-378. · 1.20 Impact Factor
[show abstract][hide abstract] ABSTRACT: At present, it is a trend for domestic and foreign port clusters to re-integrate the region's ports and optimize the allocation of resources, with the regional economic concept, in order to get scale advantages, enhance the competitiveness of ports and attain the international competitive advantages. This paper analyzed the theories of optimizing the allocation and integration of port cluster resources. Taking Shandong coastal port cluster as an example, it established Port's C-D Production Function Model, evaluates the status of resources allocation of port cluster, according to Denison's decomposition of scientific and technological progress rate. Finally, it gave the measures and proposals, hoping to provide references for the optimal resources allocation and integration of domestic and foreign port clusters.
[show abstract][hide abstract] ABSTRACT: Finding a polygon to approximate the contour curve with the minimal approximation error ε under the pre-specified number of vertices, is termed min-ε problem. It is an important issue in image analysis and pattern recognition. A discrete version of particle swarm optimization
(PSO) algorithm is proposed to solve this problem. In this method, the position of each particle is represented as a binary
string which corresponds to an approximating polygon. Many particles form a swarm to fly through the solution space to seek
the best one. For those particles which fly out of the feasible region, the traditional split and merge techniques are applied
to adjust their position which can not only move the particles from the infeasible solution space to the feasible region,
but also relocate it in a better site. The experimental results show that the proposed PSO-based method has the higher performance
over the GA-based methods.
Advances in Neural Networks - ISNN 2008, 5th International Symposium on Neural Networks, ISNN 2008, Beijing, China, September 24-28, 2008, Proceedings, Part I; 01/2008
[show abstract][hide abstract] ABSTRACT: The effect of coagulation coupled with chlorination (i.e., pre-, inter-, and post-chlorination) on the formation of disinfection by-products (DBPs) and the removal efficiency of DBPs precursors were investigated. Compared with coagulation coupling with pre-chlorination, coagulation coupled with inter-chlorination could lead a higher removal efficiency of dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA) and chloroacetic acids formation potential (CAAsFP). The CAAsFP/DOC value of residual DOC showed that coagulation with inter-chlorination has a beneficial effect on CAAs precursors removal. More DBPs were produced during inter-chlorination than that of pre-chlorination at pH 7.5, while less DBPs were produced during inter-chlorination than that of pre-chlorination at pH 5.5. In addition, the precipitate of humic acid (HA) after coagulation was chlorinated to study the kinetics of chlorine decay. The results showed that coagulated-HA had a higher reactivity with chlorine than aqueous-HA at pH 7.5. Furthermore, the trends of zeta potential during coagulation process suggested that the distribution of chlorine species had significant influence on the removing of DBPs precursors by coagulation coupled with chlorination.
[show abstract][hide abstract] ABSTRACT: Merging Unit is the information source of secondary equipment in intelligent distribution substation. To realize condition monitoring and judgment and basic processing of sampled value in Merging Unit (the advanced function of Merging Unit) is conducive to the improvement of communication between process level and bay level devices as well as data reliability. In this paper, the conception of Merging Unit and the hardware platform of it developed by the authors are firstly introduced. In the following part, the fault diagnosis criteria of electromagnetic instrument transformer and electronic transformer are summarized and analysis respectively, and the feasibility of the advanced function is analyzed with the method of data compensation is proposed. Finally, the merit and demerit of advanced function of Merging Unit is elaborated. The work of this paper is of significance to condition monitoring and information sharing in intelligent distribution substation.
[show abstract][hide abstract] ABSTRACT: Merging unit is the important interface device of mutual inductor and protection. To ensure the merging unit real-time and synchronicity is the key questions for a reliable and stable operation system. This paper adopts EP1C3T144 series chip of ALTERA, the research of merging unit contain three parts: capture and detection of synchronized signal, the configurable type of sampling frequency, the analysis of time information. Through Quartus II simulation for methods, The results show that it can capture PPS signal accurately and extract time information rapidly, so that to achieve the configurable attribute of sampling frequency. To solve the problem of merging unit by EP1C3T144 not only ensure synchronicity of the system, but also reduce the hardware design and equipment cost.