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1.
The residues of 13 organochlorine pesticides (OCPs) in surface water and HCHs and DDTs in suspended particulate matter (SPM) from rivers and lakes in Yangtze River catchment of Wuhan, China, were investigated. The concentration of total OCPs in surface water varied from 1.01 to 46.49 ng l−1 (mean 10.55 ng l−1). The levels of total HCHs (ΣHCH) and total DDTs (ΣDDT) in surface water were in the range of 0.55–28.07 ng l−1 and lower than detection limit to 16.71 ng l−1, respectively, which was lower than Chinese standards on the whole. For OCPs residues in SPM, the mean levels varying from 0.20 to 34.72 ng l−1 and 0.46 to 2.72 ng l−1 for ΣHCH and ΣDDT, respectively, which ranked the relatively higher levels among Chinese studied rivers. Results from this investigation showed that previous excessive usage of technical OCPs was the main reason for the residues of HCHs and DDTs both in surface water and SPM, although some new sources were likely to occurred in the region. Apart from the OCPs in SPM originated from upstream in flood season, one of the important sources of OCP residues both in water and SPM in Yangtze River was supposed to be the inputs of its tributaries. Additionally, in situ water-SPM phase distributions of OCPs indicated that HCHs tended totransport with water as well as DDTs was prone to combine with SPM in Yangtze River catchment of Wuhan.  相似文献   

2.
The contamination of semi-volatile organic compounds (SVOCs) in the surface sediments of the Guan River Estuary, China was fully investigated. Total concentrations of 56 species of SVOCs ranged from 132 to 274 ng/g with an average of 186 ng/g (dry weight). Polycyclic aromatic hydrocarbon (PAH) concentrations were positively correlated with clay content and negatively correlated with sediment grain size. Source identification indicated that PAHs originated mainly from pyrolytic sources. However, intense ship traffic in the estuary may provide sources of petrogenic PAHs. Organochlorine pesticides (OCPs) mainly originated from direct input of dichlorodiphenyltrichloroethanes (DDTs) during some industrial processes. The SVOC concentrations were also compared with International Sediments Quality Guidelines and Sediments Quality Criteria, and the results indicated that negative biological impacts may originate from high concentrations of FLO, p,p′-DDE, and total DDTs.  相似文献   

3.
The Bay of Gokova in Southeastern Aegean Sea (Turkey) is important by the potential of agricultural, municipal, and tourism activities. In addition, there is no industrial plant within the area in the Aegean Sea. Kad?n Creek (Azmak) and Ak?ap?nar Creek (Azmak) flowing into the inner Gokova Bay are one of the important factors in determining the character of the inner Gokova Bay. In this study, nine stations were selected in the inner Gokova Bay, Kad?n Creek, and Akcap?nar Creek. The concentrations of Cd, Cu, Fe, Pb, and Zn were measured in suspended particulate matter (SPM) and sediments. The samples of sediments and SPM were collected in between February 2008 and September 2008. The aim of the study is searching the change of concentrations of Cd, Cu, Fe, Pb, and Zn in suspended particulate matter and sediments in the inner Gokova bay, Kad?n Creek, and Ak?ap?nar Creek. It has been identified that the metal concentrations in the creeks are higher than the metal concentrations in the marine environment. It has also been observed that the concentrations of Pb, Cd, and Cu in summer season have been higher than in the winter season, but the concentrations of Fe and Zn have not shown a significant difference between in summer and winter seasons. The obtained results show that the some heavy metals are caused by the agricultural, municipal, and tourism activities operating in the coastal areas and terrestrial environment, and they are transported from the creeks to the Gokova Bay by suspended particulate matter.  相似文献   

4.
Ambient air monitoring for suspended particulate matter was carried over a period of one year in some coal mining areas of the Raniganj coalfield. Concentrations of seven elements in suspended particulate matter were determined. The set of data obtained was analysed to determine the sources of trace elements by factor analysis. The data could be interpreted on the basis of five factors. These factors are attributed to various sources of particulate matter by noting the dependence of factors on the elements.  相似文献   

5.
Polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in 25 surface sediments in three cities (Nantong, Wuxi, and Suzhou) in the Yangtze River Delta, eastern China were measured. The mean concentrations were 378, 45.8, 1.98, 4,002 ng/g for PBDEs, OCPs, PCBs, and PAHs, respectively. Their levels in the sediments in the three cities were generally consistent with the city industrialization. PBDEs and OCPs were markedly dominated by deca-BDE (>90 %) and DDTs (>70 %). A principle component analysis of the analytes identified three major factors suggesting different sources of the contaminants in the sediments. PBDEs and the organic carbon in the sediments have common sources from industrial activities; whereas OCPs and PCBs, correlated with the second factor, were mainly from historical sources. The third factor with loadings of PAHs is indicative of various combustion sources. Ecological risk assessment indicated that the potential highest risk is from DDTs, for which 22 sites exceed the effects range low (ERL) values and three sites exceed the effects range median (ERM) value.  相似文献   

6.
Sources, partitioning and toxicological risk of 15 priority polycyclic aromatic hydrocarbons (PAHs) in surface sediments from drinking water sources of Taihu Lake, with an area of 2428 km(2) located in the most developed and populated area of China, were studied, and the results were compared with those in other lakes of China and the USA. Concentrations of the 15 PAHs in sediments ranged from 436.6 to 1334.9 ng g(-1) (dw). Gasoline combustion, coal combustion, diesel combustion from shipping and spillage of petroleum were apportioned to be the main sources of PAHs in this area by principal component analysis, which contributed 35.19%, 26.43%, 25.41% and 12.97% to the PAH sources estimated by further multiple linear regression. Levels of PAHs in sediments were negatively correlated with contents of clay and fine silt (<16 μm), while positively with contents of medium silt, coarse silt and sand (>16 μm). Humin with size larger than 16 μm contained the largest part of the burden of PAHs in sediments, but the specific partitioning domain (bound humic acid, lipid or insoluble residue) depended on properties of organic matter reflected by optical absorbance at 465 and 665 nm. Total toxic benzo[a]pyrene equivalent (TEQ(carc)) of the carcinogenic PAHs in sediments varied from 31.8 to 209.3 ngTEQ(carc) g(-1). Benzo[a]pyrene and dibenzo[a,h]anthracene contributed 45.36 and 25.31% to total TEQ(carc), posing high toxicological risk to this area.  相似文献   

7.
The present paper is the first document of heavy metal levels in surficial sediment, water and particulate matter of the Gediz River collected from five different sites in August, October 1998, February, June 1999. The present work attempts to establish the status of distribution and environmental implications of metals in the sediment, water and particulate matter and their possible sources of derivation. The concentrations of mercury ranged 0.037–0.81, 120–430; lead 0.59–1.5, 190–8,100; copper 0.24–1.6, 30–180; zinc 0.19–2.9, 10–80; manganese 30–170, 20–490; nickel 0.39–9.0, 100–510; iron 1.3–687, 100–6,200 μg/l in water and particulate matter, respectively. The maximum values in water were generally obtained in summer periods due to industrial and agricultural activities at Muradiye. The particulate metal concentrations also generally showed increased levels from the upper Gediz to the mouth of the river. Calculation of metal partition coefficients shows that the relative importance of the particulate and the water phases varies in response to water hydrochemistry and suspended solid content, but that most elements achieve a conditional equilibrium in the Gediz River. The metals ranged between Hg: 0.25–0.49, Cr: 59–814, Pb: 38–198, Cu: 15–148, Zn: 34–196, Mn: 235–1,371, Ni: 35–175, and Fe: 10,629–72,387 mg/kg in sediment. The significant increase of metals found in Muradiye suggested a pollution effect, related to anthropogenic wastes. Also, relatively high concentrations of Ni and Mn occurred in sampling site upstream, due to geochemical composition of the sediments. Maximum values of contamination factor for metals were noticed for sediment of Muradiye. The sampling stations have very high degree of contamination indicating serious anthropogenic pollution.  相似文献   

8.
Sediments and suspended particulate matter taken from about 100 sampling sites along the River Elbe from the source to the mouth during the period 1992 and 1998 have been analyzed for the concentrations of more than 60 elements in each sample. The analytical data were subsequently processed by means of multivariate statistics in order to characterize the charge of the River Elbe with inorganic pollutants to elucidate pollution trends. Using factor analysis 18 elements were found to be enriched by human activities. By means of cluster analysis--using the 18 anthropogenically influenced elements as variables--the sampling sites were aggregated into groups having similar element distributions. Thus, the entire stretch of the River Elbe was divided into three sections of characteristic elemental pollution. Finally, the trends in anthropogenic pollution within the characteristic regions since the early nineties were assessed. It turned out that most of the anthropogenically influenced elements showed a decrease in the upper and middle parts of the river, whereas no decrease could be verified in the estuary region.  相似文献   

9.
Atmospheric trace phthalic esters (PAEs) carried by total suspended particulates were systematically investigated. A total of 450 air samples were collected at six typical locations and three specific micro-environmental sites (a stadium with a new plastic track, new cars, and a farming greenhouse with plastic film) in Nanjing metropolitan area of China from April 2009 to January 2010. The samples were analyzed by high-performance liquid chromatography and ultraviolet detection. The results are summarized as follows: (1) The dominant PAEs are dimethyl phthalate (DMP), dibutyl phthalate (DBP), and diethylhexyl phthalate (DEHP), which were found in the atmosphere of Nanjing. The average concentrations of DMP, DBP, and DEHP were 10.5?±?1.2, 62.3?±?4.5, and 33.3?±?2.5?ng?m(-3), respectively, constituting 9.9%, 58.7%, and 31.4% of total PAEs (106?±?8.2?ng?m(-3)). (2) The dynamic variations of atmospheric PAEs in the three specific micro-environmental sites showed that the PAE concentrations in the stadium with a new plastic track reduced to normal after 1?month remediation, while new cars need 6?months to remove their effect. The levels of PAEs in a farming greenhouse with plastic film were relatively high, but little PAEs accumulated in vegetables. (3) The vertical profiles from 1.5 to 40?m above ground display some fluctuations in PAE concentration, but no significant height dependence. This information will make a valuable contribution to the examination of the influence of atmospheric PAEs on the environment and human health.  相似文献   

10.
Total suspended particulates (TSP) were collected with a high volume sampler from the indoor work environment of 23 industries in Al-Rusayl Industrial Estate in Muscat, Oman. The values measured ranged from 39 microg m(-3) to 1033 microg m(-3). TSP in the ambient air of the area was found to have an average value of 1802 microg m(-3). TSP were analyzed for Pb, Cu, Ni, Zn and Cr. Compared to other metals, Pb emission was high with values ranging from 3 to 15 109 ng m(-3) with the mean value being 1 293 ng m(-3); Cu concentration varied from 3 to 2600 ng m(-3) with a mean value of 131 ng m(-3); Ni concentration ranged from 6 to 46 ng m(-3) with a mean value of 17 ng m(-3); Cr concentration ranged from 1 to 133 ng m(-3) with a mean value of 23 ng m(-3) while that of Zn varied from 0.01 to 1 978 ng m(-3) with the mean value being 464 ng m(-3). The concentrations of Pb, Ni, Cu, Cr, and Zn in the ambient air were also measured and found to have the following values: 122, 18, 16, 5 and 0.01 ng m(-3), respectively. These values indicate that the industries in the area do not contribute significantly to heavy metal air pollution.  相似文献   

11.
The concentrations of trace metals (Cu, Zn, Mn, Ni, and Fe) from suspended particulate matter (SPM) and biota in Izmir Bay (Eastern Aegean Sea) were studied in order to evaluate the environmental impact of the anthropogenic metals before building of Wastewater Treatment Plant. SPM samples were collected in wet and dry periods from Izmir Bay. Metal concentrations in SPM (Cu, 0.36–2.19; Mn, 0.07–11.3; Ni, 0.43–7.81; Zn, 7.33–269; Fe, 1.00–266 μgdm − 3) were comparable to those reported for other moderately polluted bays. Maximum metal concentrations in SPM were observed during summer season. SPM metal concentrations displayed a clear spatial trend with values increasing with proximity to urban centers. Cu and Zn concentrations in SPM were especially high in the inner bay. SPM were found to be contaminated by Zn. The vertical profile of Mn, Zn, and Ni concentrations in SPM had a maximal value at the upper layer and decreased to minimal value at the bottom layer of the inner bay in summer, in contrast to the observed pattern of Fe and Cu. Maximum Cu concentrations were obtained in Penaeus kerathurus. Also, maximum Zn and Fe concentrations were found in Mytilus galloprovincialis. Relatively high Cu levels were found in Sardina pilcardus and Mullus barbatus than other fish species. Besides, Cu levels were lower in Diplodus annularis and Merluccius merluccius. Finally, metal levels in biota tissues were lower than the limits of European Dietary Standards and Guidelines.  相似文献   

12.
Environmental impact assessments (EIAs) effectiveness and accessibility by the public is determined by local environmental enforcement and regulation. Massive energy infrastructure projects like China's Belt and Road initiative (BRI) could accentuate social and economic costs, as regulation is deferred to host countries with varying levels of domestic enforcement. To fill major gaps in the public evaluation of EIA practices and results, our objective here is to present an open-source approach for evaluating localized air pollution health impacts for BRI-financed coal-fired power plants. This analysis focuses on one specific problem, additional attributable mortality from stroke, ischemic heart disease, and chronic obstructive pulmonary disease for adults ages 25–84 from fine particulate matter (PM2.5), known to be major risk factor for premature deaths globally. As a concrete example, we examine the case of the Port Qasim power plant located near Karachi, Sindh Province, Pakistan. We present results for two main scenarios: a base case, assuming fully operational pollution control technologies, in particular electrostatic precipitators (ESP); and an alternative case without ESPs. All material and methods for replicating this analysis for the case study and for other projects are available in our institutional open repository. Our approach can be applied immediately to virtually any source location in the world, due to the public and global availability of input data.SynopsisWe present an open-source approach for evaluating localized health impacts due to fine particulate matter emitted from coal-fired power plants.  相似文献   

13.
Polycyclic aromatic hydrocarbon (PAH) analyses of surface sediments from the Cross River estuary by gas chromatography–mass spectrometry indicated natural diagenetically derived PAHs in the upper estuary, with minor and variable amounts of petrogenic and combustion-derived PAHs from human activities (lower estuary). The occurrence of significant amounts of perylene (average 23% of all PAHs) with the diagenetic natural PAHs in the middle estuary bordered by mangrove forests supports its origin from terrestrial organic matter. The natural PAHs represent the highest percentage (average 76%) of the total PAHs in this tropical environment. The traditional geochemical parameters, including the petrogenic PAHs, confirmed trace petroleum contamination in the estuary. Specific PAH ratios such as Fl/Py and Fl/(Fl+Py) also support this source contribution.  相似文献   

14.
Suspended particulate matter (SPM), sediments and clams were collected at three sites in Jiaozhou Bay to assess the magnitude of trace metal pollution in the area. Metal concentrations in SPM (Cu: 40.11–203; Zn: 118–447; Pb: 50.1–132; Cd: 0.55–4.39; Cr: 147.6–288; Mn: 762−1670 μg/g), sediments (Cu: 17.64–34.26; Zn: 80.79–110; Pb: 24.57–49.59; Cd: 0.099–0.324; Cr: 41.6–88.1; Mn: 343−520μg/g) and bivalves (Cu: 6.41–19.76; Zn: 35.5–85.5; Pb: 0.31–1.01; Cd: 0.51–0.67; Mn: 27.45−67.6 μg/g) are comparable to those reported for other moderately polluted world environments. SPM showed a less clear pattern. Metal concentrations in sediments displayed a clear geographical trend with values increasing with proximity to major urban centers. The clams (on dry weight) showed a complex pattern due to the variability introduced by age-related factors. Cd showed an apparent reverse industrial trend with higher concentrations in clams collected at distant stations. Zn, Pb and Mn showed no clear geographical pattern, whereas Cu increased in the clams collected in the most industrialized area. In addition, the bioaccumulation factors (BAF) were calculated. The result indicated that the studied Ruditapes philippinarum in Jiaozhou Bay possessed different bioaccumulation capacities for Cd, Zn, Cu, Pb and Mn, and Cd, Zn had a relatively high assimilation of those metals from sediment particles. A significant relationship with clam age was observed for Zn (positive) and Cu (negative) suggesting different physiological requirements for both metals with age. Trace metal concentrations measured in the tissue of the investigated clam were in the range considered safe by the WHO for human use.  相似文献   

15.
Suspended particulate matter (SPM), sediments and clams were collected at three sites in Jiaozhou Bay to assess the magnitude of trace metal pollution in the area. Metal concentrations in SPM (Cu: 40.11-203; Zn: 118-447; Pb: 50.1-132; Cd: 0.55-4.39; Cr: 147.6-288; Mn: 762-1670 microg/g), sediments (Cu: 17.64-34.26; Zn: 80.79-110; Pb: 24.57-49.59; Cd: 0.099-0.324; Cr: 41.6-88.1; Mn: 343-520 microg/g) and bivalves (Cu: 6.41-19.76; Zn: 35.5-85.5; Pb: 0.31-1.01; Cd: 0.51-0.67; Mn: 27.45-67.6 microg/g) are comparable to those reported for other moderately polluted world environments. SPM showed a less clear pattern. Metal concentrations in sediments displayed a clear geographical trend with values increasing with proximity to major urban centers. The clams (on dry weight) showed a complex pattern due to the variability introduced by age-related factors. Cd showed an apparent reverse industrial trend with higher concentrations in clams collected at distant stations. Zn, Pb and Mn showed no clear geographical pattern, whereas Cu increased in the clams collected in the most industrialized area. In addition, the bioaccumulation factors (BAF) were calculated. The result indicated that the studied Ruditapes philippinarum in Jiaozhou Bay possessed different bioaccumulation capacities for Cd, Zn, Cu, Pb and Mn, and Cd, Zn had a relatively high assimilation of those metals from sediment particles. A significant relationship with clam age was observed for Zn (positive) and Cu (negative) suggesting different physiological requirements for both metals with age. Trace metal concentrations measured in the tissue of the investigated clam were in the range considered safe by the WHO for human use.  相似文献   

16.
Jobos Bay, located on the southeastern coast of Puerto Rico, contains a variety of habitats including mangroves, seagrass meadows, and coral reefs. The watershed surrounding the bay includes a number of towns, agricultural areas, and the Jobos Bay National Estuarine Research Reserve (NERR). Jobos Bay and the surrounding watershed are part of a Conservation Effects Assessment Project (CEAP), involving the Jobos Bay NERR, the US Department of Agriculture, and the National Oceanic and Atmospheric Administration (NOAA) to assess the benefits of agricultural best management practices (BMPs) on the terrestrial and marine environments. As part of the Jobos Bay CEAP, NOAA collected sediment samples in May 2008 to characterize over 130 organic chemical contaminants. This paper presents the results of the organic contaminant analysis. The organic contaminants detected in the sediments included polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, and the pesticide DDT. PAHs at one site in the inner bay near a boat yard were significantly elevated; however, all organic contaminant classes measured were below NOAA sediment quality guidelines that would have indicated that impacts were likely. The results of this work provide an important baseline assessment of the marine environment that will assist in understanding the benefits of implementing BMPs on water quality in Jobos Bay.  相似文献   

17.
The levels of hexachlorocyclohexane (HCH) and dichloro-diphenyl-trichloroethane (DDT) in the water, suspended particulate matter (SPM), and sediments from Lake Small Baiyangdian were measured by gas chromatograph with a 63Ni microelectron capture detector. The residual levels of the total HCHs in the water, SPM, and sediments were 1.59?±?2.24 ng L?1, 25.42?±?1.72 ng g?1 dw (dry weight), and 0.86?±?1.44 ng g?1 dw, respectively. DDTs were not detected in the water samples. The concentrations of total DDTs were 158.79?±?1.67 ng g?1 dw in SPM and 0.46?±?1.97 ng g?1 dw in the sediments. Compared to other areas in China and abroad, the levels of residual HCH and DDT were relatively low in the water and sediments, but they were moderate to high in the SPM. Organic carbon partition coefficient values for HCH in this study were higher than previously published values and may reflect new input in this area. The residual HCHs in this area could be derived from a mixture of technical HCH and lindane because ongoing lindane use may be occurring. DDT in the majority of the study area was primarily attributed to historical discharge, but some regions may be receiving new input. The ecological risks of γ-HCH in the water were very low according to species sensitivity distribution models. The concentrations of HCH and DDT in the sediments from the study area did not exceed the sediment quality guidelines, which indicate little risk for benthic organisms.  相似文献   

18.
Concentrations of formaldehyde, acetaldehyde, acetone, propionaldehyde, i-pentanal, and butyraldehyde in residential indoor air in Hangzhou were determined. The mean concentration of the total carbonyl compounds in summer was 222.6 μg/m3, higher than that in winter (68.5 μg/m3). The concentration of a specific carbonyl in indoor air was higher than the outdoor air measurement, indicating the release of carbonyls from the indoor sources. Formaldehyde and acetone were the most abundant carbonyls detected in summer and winter, respectively. Multiple regression analysis indicated that carbonyl concentrations in residential indoor air depended on the age of decoration and furniture, as well as their concentrations in outdoor air. In addition, a primary estimation showed that the health risks of carbonyls in summer were higher than those in winter.  相似文献   

19.
The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), and organochlorine pesticides (OCPs) in surface sediments from the lower reaches of the Haihe River basin, northern China, were determined by high-resolution gas chromatograph–high-resolution mass spectrometer. The concentrations of 2,3,7,8-substituted PCDD/Fs, dl-PCBs, and total OCPs [sum of hexachlorobenzene, hexachlorocyclohexanes, and dichlorodiphenyltrichloroethane (DDTs)] in 17 sediment samples were in the ranges of 11.6–1,180,924 pg/g dry weight (dw), 18.7–50,017 pg/g dw, and 1.7–35,280 ng/g dw, respectively. The contamination levels in the samples varied significantly between the different sites. Abnormally high concentrations of PCDD/Fs, dl-PCBs, and some OCPs were found in sediments from the lower reaches of the main channel of the Haihe River and the Dagu Drainage River, which were attributed to the historical production of pentachlorophenol and other pesticides near these locations. High levels of DDTs were detected in the Yongding New River sediment, which were likely to have originated from the discharge of wastewater from a dicofol factory upstream. In samples taken from other sites, the concentrations of these pollutants were at levels comparable to those documented in other areas of China. This preliminary investigation suggests that historical pesticide production in the Haihe River basin has contributed significantly to the contamination of this aquatic ecosystem and that further attention to this issue is warranted.  相似文献   

20.
APM was collected and trace elements existing in the particles were monitored since May 1995 in this study. APM sample was collected separately by size (d < 2 microm, 2-11 microm and >11 microm) on the roof of the university building (45 m above ground) in the campus of Faculty of Science and Engineering, Chuo University, Tokyo, Japan, using an Anderson low volume air sampler. The collected sample was digested by HNO3, H2O2 and HF using a microwave oven, and major elements (Na, Mg, Al, K, Ca and Fe) were measured by ICP-AES, and trace elements (Li, Be, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Ba and Pb) were measured by ICP-MS. It was observed that the APM concentration was higher between the winter and the spring, compared to during the summer. The enrichment factor was calculated for each element in each set of APM (d < 2 microm, 2-11 microm and >11 microm). Seasonal trends of enrichment factors were examined, and the elements were classified into 3 groups according to the common seasonal behavior. It is likely that the elements in the same group have common origins. Toxic pollutant elements (Sb, Se, Cd, Pb and As) were found in small particles with d of <2 microm in concentrated levels. Antimony (Sb) had the highest enrichment factor, and the results suggested that Sb level in APM was extremely high. The origins of Sb were sought, and wastes from plastic incineration and brake pad wears of automobiles were suspected. Each set of APM (d < 2 microm, 2-11 microm and >11 microm) was classified by the shape, and the shape-dependent constituents of a single APM particle were quantitatively measured by SEM-EDX. High concentration of Sb was found in APM <2 microm and square particles. Particles less than 2 microm and square shaped particles were major particles produced by actual car braking experiments. From these experimental results it was concluded that the source of Sb in squared APM <2 microm is considered to be from brake pad wear.  相似文献   

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