| 1. |
- Duan, Hongtao, et al.
(författare)
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Two-Decade Reconstruction of Algal Blooms in China’s Lake Taihu
- 2009
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 43:10, s. 3522-3528
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Tidskriftsartikel (refereegranskat)abstract
- The algal blooming in the inland lakes has become a critically important issue for its impacts not only on local natural and social environments, but also on global human community. However, the occurrences of blooming on larger spatial scale and longer time scale have rarely been studied. As the third largest freshwater lake in China, Lake Taihu has drawn increasing attention from both public and scientific communities concerning its degradation. Using available satellite images, we reconstructed the spatial and temporal patterns of algal blooms in Lake Taihu through the past two decades. The blooming characteristics over the past two decades were examined with the dynamic of initial blooming date being highlighted. The initial blooming dates were gradually becoming later and later from 1987 to 1997. Since 1998, however, the initial blooming date came earlier and earlier year by year, with approximately 11.42 days advancement per year. From 1987 to 2007, the annual duration of algal blooms lengthened year by year, in line with the substantial increases in the occurrences of algal blooms in spring and summer months. The algal blooms usually occur in northern bays and spread to center and south parts of Lake Taihu. The increases in previous winter’s mean daily minimum temperature partially contributed to the earlier blooming onset. However, human activities, expressed as total gross domestic product (GDP) and population, outweighed the climatic contribution on the initial blooming date and blooming duration. This study may provide insights for the policy makers who try to curb the algal blooming and improve the water quality of inland freshwater lakes.
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| 2. |
- Liu, Lihui, et al.
(författare)
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Two-In-One Method for Graphene Transfer: Simplified Fabrication Process for Organic Light-Emitting Diodes
- 2018
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Ingår i: ACS Applied Materials & Interfaces. - : American Chemical Society (ACS). - 1944-8252 .- 1944-8244. ; 10:8, s. 7289-7295
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Tidskriftsartikel (refereegranskat)abstract
- Graphene as one of the most promising transparent electrode materials has been successfully applied in organic light-emitting diodes (OLEDs). However, traditional poly(methyl methacrylate) (PMMA) transfer method usually results in hardly removed polymeric residues on the graphene surface, which induces unwanted leakage current, poor diode behavior, and even device failure. In this work, we proposed a facile and efficient two-in-one method to obtain clean graphene and fabricate OLEDs, in which the poly(9,9-di-n-octylfluorene-alt-(1,4-phenylene-(4-sec-butylphenyl)imino)-1,4-phenylene) (TFB) layer was inserted between the graphene and PMMA film both as a protector during the graphene transfer and a hole-injection layer in OLEDs. Finally, green OLED devices were successfully fabricated on the PMMA-free graphene/TFB film, and the device luminous efficiency was increased from 64.8 to 74.5 cd/A by using the two-in-one method. Therefore, the proposed two-in-one graphene transfer method realizes a high-efficient graphene transfer and device fabrication process, which is also compatible with the roll-to-roll manufacturing. It is expected that this work can enlighten the design and fabrication of the graphene-based optoelectronic devices.
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| 3. |
- Shang, Hongtao, et al.
(författare)
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Bioaccumulation of PCDD/Fs, PCBs and PBDEs by earthworms in field soils of an E-waste dismantling area in China
- 2013
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Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 54, s. 50-58
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Tidskriftsartikel (refereegranskat)abstract
- A total of 60 paired samples of earthworm, corresponding soil and wormcast were collected to investigate the bioaccumulation tendency of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in earthworms from a typical E-waste dismantling area in east China. Significant correlations were observed for the total concentrations among different matrix types except for PCDD/Fs in soil and earthworm. The bioaccumulation tendency showed some differences among the contaminants. Calculated biota-soil accumulation factors (BSAFs) indicated that PCBs and PBDEs had higher bioaccumulation potential compared to PCDD/Fs, which was somewhat different from laboratory studies. The plot of mean BSAFs versus log Kow values for PCBs and PBDEs was well fitted by a second-order polynomial with the maximum BSAF at approximately log Kow of 6.5. While for PCDD/Fs, only a slightly decreasing trend was observed with increasing log Kow. Composition analysis indicated that tetra-, penta- and hexa-halogenated homologs had higher bioaccumulation levels, indicating that medium-halogenated congeners with log Kow around 6.5 are more easily accumulated by earthworms. Furthermore, the ratios of BDE-47/-99 and BDE-99/-100 showed some discrepancies with the technical products and other biotic species, suggesting different bioaccumulation potential of PBDEs in earthworm.
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| 4. |
- Shang, Hongtao, et al.
(författare)
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The presence of polychlorinated biphenyls in yellow pigment products in China with emphasis on 3,3'-dichlorobiphenyl (PCB 11)
- 2014
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 98, s. 44-50
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Tidskriftsartikel (refereegranskat)abstract
- A non-Aroclor PCB congener, 3,3'-dichlorobiphenyl (PCB 11) has recently attracted wide concerns because of its environmental ubiquity and specific sources potentially associated with yellow pigment production. In order to investigate PCB 11 and other PCBs in the yellow pigment products, 24 yellow pigment samples were collected from three different manufacturing plants in China. ∑20PCBs and PCB 11 were in the range of 50.7-9.19×10(5) ng g−1 and 41.7-9.18×105 ng g−1, respectively, which was much higher than those reported in previous study. The corresponding TEQ values ranged between 0.16 and 4.21×103 ng WHO2005-TEQ kg−1. The contribution of PCB 11 to ∑20PCBs reached up to 85.5% (median value) followed by PCB 28, PCB 77, and PCB 52 with contributions of 10.5%, 6.70%, and 5.40%, respectively. Significant differences were observed for PCB 11 concentrations among the different types of yellow pigment from the same plant and among the same sample types from different plants. The PCB 11 concentrations in diarylide yellow pigments produced from 3,3'-dichlorbenzidine were the highest in all the samples. It demonstrates that yellow pigment is a significant source not only for the widespread pollution of PCB 11 but also for other PCBs, especially for the lower chlorinated congeners.
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| 5. |
- Zhang, Haidong, et al.
(författare)
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Assessment on the occupational exposure of manufacturing workers to Dechlorane Plus through blood and hair analysis
- 2013
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 47:18, s. 10567-10573
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Tidskriftsartikel (refereegranskat)abstract
- Dechlorane Plus (DP), as a widely used flame retardant in different electrical and textile applications, has recently attracted great concern around the world. The present study investigated the DP levels and distribution in human samples from a DP manufacturing plant and a nearby area in east China. The DP concentrations ranged from 89.8 to 2958 ng/g lipid weight in whole blood and 4.08 to 2159 ng/g dry weight in hair. For the workers engaged in DP manufacturing process, their DP levels were significantly higher than those in most of the other two control groups from the nearby area. The values of anti-DP fractional abundance (fanti ratio) were commonly lower in the human samples from both the manufacturing plant and nearby area compared with those in the commercial products, and excretion as well as biotransformation are possible reasons for stereoselective accumulation of the syn-DP isomer in humans. Furthermore, a significantly positive relationship (p < 0.05) was obtained between (i) the concentrations (and fanti) in the paired blood and hair samples, indicating a similar distribution pattern of the two DP isomers in the paired samples; (ii) the DP levels in human body and the exposure time (p < 0.05), which suggests that further assessment could be needed to investigate potential long-term risks to the occupational population.
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