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101.
介绍了浙江省富阳市富伦造纸厂开发回收利用废弃牛奶盒、饮料盒的分离再利用技术,实现了不可降解废弃物的循环利用。分析了企业扩大再生产后遇到的问题,提出了相应的对策建议。  相似文献   
102.
The levels of persistent organic pollutants (POPs) were determined in 50 samples of Korean human milk. POPs include organochlorine pesticides (OCPs) [aldrin, chlordanes, dieldrin, dichlorodiphenyltrichloroethanes (DDTs), endrins, heptachlors, hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), mirex, and toxaphenes] and marker PCBs (PCB28, PCB52, PCB101, PCB138, PCB153 and PCB180). In all samples, p,p′-DDE were determined as 75.5–1115.3 ng/g fat. The compounds β-HCH and p,p’-DDT were detected at 72% and 60% of the samples, respectively. Chlordanes (nd–84.9 ng/g fat) heptachlors (nd–40.1 ng/g fat), HCB (nd–42.9 ng/g fat) and PCBs (nd–38.3 ng/g fat) were detected in several samples. The ratio of dichlorodiphenyltrichloroethylene (DDE)/DDT was 6.8, which explained that exposure of volunteers to DDT did not occur recently. Compared with the previous monitoring data, the level of marker PCBs generally decreased in the milk samples. The levels of OCPs are significantly correlated to the residential periods of the mothers but not with their dietary habits. Considering the daily intake of each OCPs, 18% of infants would ingest the amount of heptachlor exceeding the acceptable daily intake (ADI) proposed by World Health Organization (WHO). There was no sample surpassing the WHO ADI for DDTs, HCB and chlordanes.  相似文献   
103.
P. Dahl  G. Lindstrm  K. Wiberg  C. Rappe 《Chemosphere》1995,30(12):2297-2306
The absorption of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans was studied in four breast-fed infants. The absorption was measured by comparing the estimated total intake and the excretion in faeces, during 48 hours, at three different time points; 1, 2 and 3 months post parta. The levels of the analysed compounds in the human milk are typical for Sweden, i.e 20 ppt toxic equivalents for the dibenzo-p-dioxins and dibenzofurans and for the polychlorinated biphenyls 16 ppt toxic equivalents. For most of the congeners the absorption is found to be over 95%. Higher excretion is noticed for heptachlorinated and octachlorinated dioxins.  相似文献   
104.
The literature was reviewed to assess the relationship between the lipid adjusted concentration in human serum and breast milk (expressed as the serum/milk ratio) of a broad range of POPs in paired samples. Thirteen studies were identified, including seven studies that reported serum/milk ratios for polychlorinated dibenzo-dioxins and -furans (PCDD/Fs), ten for polychlorinated biphenyls (PCBs), five for polybrominated diphenyl ethers (PBDEs), and five for organochlorine pesticides (OCPs). Mean serum/milk ratios ranged between 0.7 and 25 depending on the compound and congener. For PCDD/Fs, PCBs and PBDEs, a clear trend of increasing mean serum/milk ratio by increasing molar volume, hydrophobicity and number of halogen substitutes was observed. The mean serum/milk ratios reported by the 13 studies summarized here will aid comparison between human POPs exposure studies using either serum or milk samples. More studies are needed to allow a valid comparison between data obtained from analysis of breast milk and serum samples for a broader range of POPs. Furthermore such studies may shed light on compound specific factors as well as other determinants that may affect the partitioning and partition kinetics of POPs between serum and breast milk.  相似文献   
105.
Yang YH  Chang YS  Kim BH  Shin DC  Ikonomou MG 《Chemosphere》2002,47(10):1087-1095
Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry in human milk samples from an urban and an industrial area in Korea. All PCB congeners were analyzed to characterize the congener distribution as well as to evaluate the toxic equivalent quotient (TEQ) values and the total concentration. In homologue distributions of PCBs, two distinct patterns were found. The mean concentrations of PCDD/Fs and PCBs were 15.13 and 5.64 TEQ pg/g fat (based on WHO TEF, 1997), respectively. The contamination in Korean human milk is comparable to that found in other countries. From these results a daily intake of 60 TEQ pg/kg/day for an infant was estimated. The assumptions were that the infant breast feeds for 1 year, has an average body weight of 10 kg during this period, and ingests 800 g/day of human milk containing a mean concentration of 20.84 TEQ (PCDD/Fs) pg/g fat (based on primipara mothers).  相似文献   
106.
Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry in human milk samples from an urban and an industrial area in Korea. All PCB congeners were analyzed to characterize the congener distribution as well as to evaluate the toxic equivalent quotient (TEQ) values and the total concentration. In homologue distributions of PCBs, two distinct patterns were found. The mean concentrations of PCDD/Fs and PCBs were 15.13 and 5.64 TEQ pg/g fat (based on WHO TEF, 1997), respectively. The contamination in Korean human milk is comparable to that found in other countries. From these results a daily intake of 60 TEQ pg/kg/day for an infant was estimated. The assumptions were that the infant breast feeds for 1 year, has an average body weight of 10 kg during this period, and ingests 800 g/day of human milk containing a mean concentration of 20.84 TEQ (PCDD/Fs) pg/g fat (based on primipara mothers).  相似文献   
107.
紫云英-早稻-晚稻农田系统的生态功能服务价值评价   总被引:4,自引:1,他引:3  
紫云英是南方双季稻区最主要种植的冬季绿肥作物,是我国传统农业的精髓,曾对我国粮食安全做出了重要贡献。针对紫云英-早稻-晚稻系统的生态功能服务价值进行综合评估,有助于人们更深入了解紫云英对现代生态农业发展的重要性及其直接贡献,有利于恢复发展与推广种植紫云英等稻区冬季绿肥作物和政府部门制定相关政策。论文以连续8 a的大田定位试验数据为基础,选取农产品与轻工业原料供给、大气调节与净化、土壤养分累积和水分涵养等功能服务价值,采用生态经济学方法,构建紫云英-早稻-晚稻系统的生态功能服务价值评价体系。结果表明:冬闲-早稻-晚稻和紫云英-早稻-晚稻系统生态功能服务总价值分别为64 230.89元/(hm2·a)和87 438.46元/(hm2·a),后者较之前者平均显著增加36.13%。该评价体系的各项功能服务指标中,冬闲-早稻-晚稻和紫云英-早稻-晚稻生态系统的农产品与轻工业原料供给服务价值分别达到38 777.03元/(hm2·a)和56 635.83元/(hm2·a),占系统功能服务总价值的比例均超过60%;其次为大气调节与净化和水分涵养服务价值(占比15%~22%),而土壤养分累积服务价值最低(占比<2%)。紫云英-早稻-晚稻系统的土壤养分累积服务价值主要表现为土壤有机质、速效钾和碱解氮的累积价值。由此可见,紫云英-早稻-晚稻系统能更好地兼顾经济和生态价值,而且评估结果还可为恢复发展与推广种植紫云英等稻田冬季绿肥作物的生态补偿政策提供理论依据。  相似文献   
108.
紫云英配施氮肥对稻田生态系统服务功能的影响   总被引:2,自引:0,他引:2  
马艳芹  黄国勤 《自然资源学报》2018,33(10):1755-1766
紫云英是南方稻田重要的绿肥作物,翻压还田后可替代部分氮肥,减少化肥用量,提高农产品产量和品质。基于农田生态系统服务功能价值理论与方法,选取农产品供给、气体调节、土壤养分累积和水分涵养4类服务功能,对紫云英翻压配施不等量氮肥各处理下的稻田生态系统服务功能价值进行了评估。结果表明:紫云英还田后配施氮肥提高了稻田生态系统服务功能总价值。与冬闲处理相比,冬种紫云英处理下的农产品总产出增幅达7.56%~20.83%,气体调节功能价值增幅为21.64%~37.61%,水分涵养功能价值增幅为8.74%~26.26%,稻田生态系统服务功能总价值增幅15.15%~41.39%,尤其以紫云英与氮肥配施效果较好,其中紫云英+优化施氮处理在农产品供给总价值、产投比、气体调节功能价值、涵养水分价值等方面最高。该研究初步核算了紫云英配施不等量氮肥条件下的稻田生态系统服务功能总价值,有利于全面认识冬种紫云英的综合效益,为种植绿肥的生态补偿政策提供理论依据。  相似文献   
109.
Results of systematic measurements of radiocaesium activities in milk after the Chernobyl nuclear accident are summarized. 137Cs fallout activity affects milk activity, the coefficient of correlation being 0.89. The 137Cs activities in milk in Croatia are log-normally distributed, reflecting the exponential decrease of activity. After the Chernobyl nuclear accident the 134Cs:137 Cs activity ratio in milk was 0.5, and did not differ from that for other environmental samples. The dose due to radiocaesium ingestion by milk consumption was estimated for the Croatian population, the annual collective equivalent dose being approximately 205 manSv in 1986 and 1.5 manSv in 1994.  相似文献   
110.
PCDD, PCDF, AND PCB concentrations in human milk from two areas in Finland   总被引:6,自引:0,他引:6  
Concentrations of 17 toxic 2,3,7,8-chlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and of 36 polychlorinated biphenyl congeners (PCBs) were analyzed from 167 randomly sampled human milk samples from Southern (77 samples) and Eastern (90) Finland. The level of PCDD/Fs and PCBs in human milk in Southern Finland was about 25% higher than those from Eastern Finland. The level of PCDD/Fs in human milk in Finland was the same as in Sweden, 30–50 % lower than in milk from Central Europe but about 45% higher than values from Norway or Russia. The PCB concentrations in Southern Finland were at the same level as in the Netherlands, and in Eastern Finland at the same level as in Norway. The levels of PCDD/Fs and PCBs decreased with increasing number of children: the third child was exposed to about 70% of the amount of PCDD/Fs and PCBs as compared with the first child, and the eighth to tenth child to about 20%. The congener patterns of PCDD/Fs and PCBs in Finnish human milk were similar to the countries of Central Europe, however, the levels of penta- and heptachlorinated furans were slightly higher than in milk from other countries.  相似文献   
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