Urbanization impairs surface water quality: eutrophication and metal stress in the Grand Canal of China

Rapid urbanization leads to degradations upon water quality via eutrophication and pollution, but there are a lack of studies on patterns of water quality change to urbanization by level or process. China has achieved the most rapid urbanization in the world within the past three decades, and its urban development is diverse at level. Nine towns and cities at various development levels along the historic Grand Canal (approximately 1500？years old) were selected to reveal direct linkages between surface water quality and extent of urbanization. Surface water quality in the urban sections of the Grand Canal was impaired by both eutrophic nitrogen and phosphorus and metals. Although metals mostly remained at concentrations permissible to the Chinese National Environmental Standard for Surface Water Quality (GB3838-2002), the concentrations of metals in most urban canal water might impose an unacceptable effect on aquatic communities according to the Criterion Continuous Concentration from the National Recommended Water Quality Criteria for Priority Toxic Pollutants (US EPA 2006). The loadings of metals in the urban canal were found relating to local industrial activities. The level of urbanization, in this study, was significantly related to water quality parameters in a descending order of electrical conductivity？>？nutrients？>？metals. This study suggests that significant mitigation strategies are required for the Grand Canal of China for a sustainable urbanization goal

Sensitive and Versatile Detection of the Fouling Process and Fouling Propensity of Proteins on Polyvinylidene Fluoride Membranes via Surface-Enhanced Raman Spectroscopy

<p>Membrane fouling is the major drawback of membrane-based technologies because it will lead to severe flux declines and the need to clean or replace the fouled membrane. A technique capable of early diagnosis, process monitoring, and evaluation of the role of different foulants playing in the fouling process is crucial for the fouling control. We develop surface-enhanced Raman spectroscopy (SERS) as a new and versatile tool to investigate the fouling process of protein on PVDF (polyvinylidene fluoride) membranes as well as the fouling propensity of three different proteins. We optimized the aggregation level and volume of SERS-active Ag sol and the spectra acquisition method combined with a statistical analysis method to ensure a high detection sensitivity, signal uniformity, and stability. We then used SERS for the early diagnosis of the fouling process and determining when the membrane pores would be blocked. The fouled area was visualized by a combination of the silver staining and Raman mapping. The fouling propensity of different proteins was studied by comparing the relative SERS band intensities of different proteins on a glass slide and after membrane filtration. Compared with fluorescence-based techniques, the narrow, well-resolved Raman band, especially the use of the same excitation line and laser power, endows SERS the ability to compare the fouling propensity in a very simple way.</p

铅负载-氧化铝催化剂对烟气中多环芳烃的氧化特性

<p>A series of Pd/&gamma;-Al₂O₃ catalysts with various Pd loadings was prepared via incipient-wetness impregnation method under different synthesis conditions. The structural and textural properties of the synthesized catalysts were characterized by XRD, N₂ adsorption/desorption, TEM, H₂-TPR, and SEM-MAPS; their catalytic performance in the elimination of polycyclic aromatic hydrocarbons (PAHs) in coal-fired flue gas by oxidation was investigated. The results revealed that the PAHs removal efficiency over various Pd-loaded catalysts fluctuates between 67.3% and 93.5%; the conversion of PAHs increases with the Pd loading in the catalyst. Moreover, a better oxidation activity of these catalysts is observed for the PAHs with higher ring-cycles; nevertheless, the removal rates based on the toxicity equivalence quantity (TEQ) for all PAHs are higher than 90%. The Pd/&gamma;-Al₂O₃ with a Pd loading of 0.2% and calcined at 600&deg;C exhibits the best catalytic performance for PAHs oxidation, with a removal rate of 93.5% at 300&deg;C.</p><!-- articleText --

Characterization of dissolved organic matter from Australian and Chinese source waters by combined fractionation techniques

<p>The character of dissolved organic matter (DOM) in source waters from two countries (Australia and China) was investigated using an extended fractionation technique by combining resin adsorption, ultrafiltration and high performance size exclusion chromatography. There are distinctive chemical characteristics associated with DOM origins. Australian sourced DOM had higher hydrophobic acid (HoA) content and exhibited a more pronounced humic character, indicating a higher influence from allochthonous organics (decayed plant bodies from vegetated catchments). The higher content of hydrophobic base and neutral components found in Chinese DOM, may be attributed to the effects of increasing pollution caused by the rapid urbanization in China. The molecular weights (MWs) of aquatic HoA are predominantly in the moderate (e.g. 1&ndash;10 kDa) or small (e.g. &lt;1 kDa) ranges. This suggests that aquatic HoA should not be assumed as high MW organics without experimental validation. It is also found that some of the low MW compounds in our samples were hydrophobic, which could explain the observation of low MW organic compounds being able to be removed by conventional treatment processes.</p

Bisphenol A induces a rapid activation of Erk1/2 through GPR30 in human breast cancer cells

<p>Bisphenol A (BPA) has been considered as an endocrine disruptor due to its ability to interact with estrogen receptors (ERs). While G protein-coupled receptor 30 (GPR30) is a novel estrogen receptor, its role in BPA-induced activation of Erk1/2 remains unknown. Human breast cancer cell lines, MCF-7, MDA-MB-231 and SKBR3, were used as experimental models to discriminate between ERs-dependent, putative ERs-independent and/or GPR30-associated effects. BPA induced a rapid activation of Erk1/2 in both ER&alpha;/&beta;-positive and negative breast cancer cells, and this effect was not blocked with an ER antagonist, ICI 182,780. A small interfering RNA assay revealed that the expression of GPR30 was necessary for BPA-induced activation of Erk1/2 and transcriptional regulation of c-fos. In addition, BPA regulates the expression of c-fos likely through an AP1-mediated pathway. As a conclusion, GPR30 plays an important role in the BPA-induced activation of Erk1/2 in a manner distinguishable from that in ER&alpha;-mediated signaling.</p

基于森林调查的福建省森林植被碳储量潜力研究

Carbon storage in forest vegetation of Fujian Province plays a significant role in the terrestrial carbon budget in China. The purposes of this study are: (1) to evaluate how the afforestation and reforestation programs established in Fujian Province influence carbon storage in forest ecosystems; (2) to assess the influence of tree species, forest age and ownership changes on vegetation carbon storage; and (3) to explore strategies for increasing vegetation carbon potentials. Data from seven Chinese Forest Resource Inventories and 5,059 separate sample plots collected between 1978 and 2008 were used to estimate vegetation carbon storage in the whole province. In addition, uncertainty analysis was conducted to provide the range of our estimations. Total forest vegetation carbon storage increased from 136.51 in 1978 to 229.31 Tg C in 2008, and the forest area increased from 855.27&times;104 to 1,148.66&times;104 ha, showing that the Fujian forests have a net vegetation carbon increase of 96.72 Tg C with an annual increase of 4.84 Tg C over the study period. Carbon storage varied with dominant forest species, forest age and forest ownership, suggesting that increases in vegetation carbon potentials can be achieved through selection of forest species and management of age structures. Implementation of afforestation and reforestation programs in Fujian Province over the past three decades has made a significant contribution to forest carbon storage. Vegetation carbon storage can be further increased by increasing the proportion of mature, broadleaved and state-owned forests

In situ encapsulating silver nanocrystals into hydrogels. A

We found that Ag(I) could serve as a &ldquo;bridging agent&rdquo; for triggering sodium carboxymethylcellulose (NaCMC) solution to form a hydrogel which enabled Ag nanocrystals to be in situ produced and encapsulated into the stable gel matrix by means of photoreduction; the conceptual system could act as a novel signaling platform for thiol-containing amino acids or small peptides, operating in a &ldquo;self-assembly and disassembly&rdquo;model