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Spatiotemporal correlations between water quality and microbial community of typical inflow river into Taihu Lake, China 全文
2022
Zhang, Yajie | Zhang, Ye | Wei, Lecheng | Li, Mengyan | Zhu, Weitang | Zhu, Liang
Changxing River, which is a typical inflow river into Taihu Lake and occurs severe algae invasion, is selected to study the effect of different pollution sources on the water quality and ecological system. Four types of pollution sources, including the estuary of Taihu Lake, discharge outlets of urban wastewater treatment plants, stormwater outlets, and nonpoint source agricultural drainage areas, were chosen, and next-generation sequencing and multivariate statistical analyses were used to characterize the microbial communities and reveal their relationship with water physicochemical properties. The results showed that ammonia nitrogen (NH₄⁺-N), total nitrogen (TN), and total phosphorus (TP) were the main pollutants in Changxing River, especially at stormwater outlets. At the same time, the diversity of microbial communities was the highest in the summer, and dominant microbes included Proteobacteria (40.9%), Bacteroidetes (21.0%), and Euryarchaeota (6.1%). The results of BIOENV analysis showed that the major seasonal differences in the diversity of microbial community of Changxing river were explained by the combination of water temperature (T), air pressure (P), TP, and CODMₙ. From the perspective of different pollution types, relative abundances of Microcystis and Nostocaceae at the estuary of Taihu Lake were correlated positively with dissolved oxygen (DO) and pH, and relative abundances of Pseudomonas and Arcobacter were correlated positively with concentrations of TN and nitrate nitrogen (NO₃⁻-N) at stormwater outlets. This study provided a reference for the impact of pollution types on river microbial ecosystem under complex hydrological conditions and guidance for the selection of restoration techniques for polluted rivers entering the important lake.
显示更多 [+] 显示较少 [-]Do environmental regulation and urbanization help decouple economic growth from water consumption at national and subnational scales in China? 全文
2022
Wang, Qiang | Zhang, Fuyu | Li, Rongrong
Moving to economic growth without water consumption growth is essential to sustainability of both water and economy. This work is aimed to estimate the decoupling state between economic growth and water consumption and then to investigate the effects of urbanization and environmental regulation on water consumption at national and subnational scales using panel data of 30 provinces in China from 2004 to 2019. The decoupling results show that (i) there are only two types between China’s water consumption and economic growth: weak decoupling (80%) and strong decoupling (20%); (ii) the weak decoupling has transitioned to strong decoupling after 2013; and that (iii) the decoupling degree of the water-poor region is weaker than that of the water-rich region. The results of causal relationships estimation show that an average 1% increase in urbanization level and environmental regulation leads to 0.3359% and 0.0104% drop in water consumption, respectively, which indicates that urbanization and environmental regulation have inhibited water consumption at the national scale. At the subnational sale, the effects of environmental regulation and urbanization on water consumption are heterogeneous. An average 1% increase in environmental regulation led to only a 0.0161% drop in water consumption in the water-poor region, whereas an average 1% increase in urbanization level led to only a 0.9838% drop in water consumption in the water-rich region. This means that the inhibition of environmental regulation on water use appears in the water-poor region, while the inhibition of urbanization is more prominent in the water-rich region.
显示更多 [+] 显示较少 [-]Testing the impact of first-mover advantage on household energy-related carbon emissions: an exploratory study from six urban agglomerations in China 全文
2022
Zeng, Jingjing | Xu, Li | Qu, Jiansheng | Han, Kŭm-ok | Wu, Jinjia | Bai, Jing | Li, Hengji
The household sector has become the second-largest source of energy consumption and CO₂ emissions in China. It is important to understand the trends and changing mechanisms of household energy-related CO₂ emissions (HECEs) in different social stages for mitigating the impact of climate change. However, the existing trends in HECEs and whether they are congruent with the expectation that HECEs in later developed areas are lower than those in priority areas under the same economic level are unclear. Here, we compared the per capita HECEs (PHECEs) of urban agglomerations under the same economic standards and analyzed the causes of the comparative results. We find that (1) HECEs increased rapidly from 3.65 × 10⁸ t to 12.42 × 10⁸ t during 1995–2017, with an average annual growth rate of 14.19%; (2) urban agglomerations that developed earlier do not have higher PHECEs. The PHECEs of urban agglomerations with moderate and later development do not decrease under increased social, technological, and cognitive conditions; (3) carbon intensity (CI), energy intensity (EI), and per capita regional gross domestic product (PCG) have a positive impact on PHECEs, and the potential impact of EI on PHECEs reduction is greater; (4) the effects of CI, EI, and PCG on PHECEs in different urban agglomerations are various. However, these effects are similar within urban agglomerations. Our study provides a reference for reducing CO₂ emissions in the household sector and for the green development of urban agglomerations and emphasizes that the growth of HECE at a reasonable level is necessary when technology does not meet sufficient constraints.
显示更多 [+] 显示较少 [-]Fostering land use sustainability through construction land reduction in China: an analysis of key success factors using fuzzy-AHP and DEMATEL 全文
2022
Li, Qiang | Wang, Lifang | Zhu, Yuming | Mu, Bingxu | Ahmad, Naveed
Construction land reduction (CLR) is an important instrument for achieving environmental sustainability by reducing intensive land use, controlling the unrestrained extension of construction land, and ensuring a balance between construction and arable lands in China. Existing studies on key factors of CLR projects are rare, lacking comprehensive and systematic understanding. In this study, the fuzzy-AHP and fuzzy-DEMATEL methods were used to obtain the comprehensive causality and centrality values, whereby factors with a comprehensive causality value larger than 0 and a comprehensive centrality ranking in the top 20% were identified as key success factors (KSFs). Results indicate that KSFs include the presence of a supportive policy for CLR, coordination with the original landowner, coordination with the surrounding residents, a diversity of enterprises participating in the CLR, a legal environment, and land acceptance and testing standards. This paper lays a theoretical foundation for CLR projects and provides guidelines for achieving successful project implementations.
显示更多 [+] 显示较少 [-]How do energy prices affect economic environment under different price regulation policies? 全文
2022
Xu, Haitao | Pan, Xiongfeng | Song, Malin | Lu, Yuduo
Energy is an essential factor for the survival of industries. Energy can affect the industrial productivity related to the economic activities, and the fluctuation of energy price will influence the final energy consumption level. In this paper, we use the input–output price model to study the relationship between the fluctuation of energy price and the change of economic level under different price control scenarios. The results show that the energy price fluctuation has high conduction efficiency on the general price index in the non-price-regulated scenario. Comparing the simulation results obtained from different years, this paper found that the magnitude of price conduction effect is closely related to the proportion of energy consumption. When the energy price is regulated by the government, the conduction effect of the energy price is limited. The policy effectiveness of regulation is related to the extent of price volatility of energy sources located at the upstream of the production chain of the regulated object. Through the SVAR model, this paper also found that the conduction effect of energy price fluctuation has obvious hysteresis, and the lag period of conduction effect on PPI is longer than that on CPI.
显示更多 [+] 显示较少 [-]Fabrication and characterization of electrospun zein/nylon-6 (ZN6) nanofiber membrane for hexavalent chromium removal 全文
2022
Ansari, Sorth | Ahmed, Naveed | Mahar, Rasool Bux | Khatri, Zeeshan | Khatri, Muzamil
Zein has drawn attention for its great potential for biodegradability and adsorption of hexavalent chromium Cr(VI) that is a carcinogenic industrial pollutant. Zein is a biopolymer extracted from corn and is used for many purposes, but because of its poor stability in aqueous solution, a novel composite of zein and nylon-6 was used to synthesize a nanofibrous membrane using electrospinning to improve its stability and tensile strength. The scanning electron microscope (SEM) image of the zein/nylon-6 (ZN6) nanofiber membrane showed a smooth, beadless, and continuous structure of the nanofibers, but the Fourier transform infrared (FTIR) spectrum of pristine and Cr(VI) saturated ZN6 showed that peaks of secondary amide, carbonyl, and hydroxyl functional groups were involved in adsorption. Optimized experimental parameters were obtained with pH 2.0, contact time 60 min, adsorbent dosage 25 mg, and adsorbate concentration 5.0 mg Cr-VI/mL. Experimental results show that the ZN6 nanofibers removed 87% Cr(VI) with an adsorption capacity of 4.73 mg/g at ambient temperature. Also, the Langmuir isotherm fits well, and the adsorption process followed a pseudo-2ⁿᵈ-order kinetics with r² of 0.90 and 0.99 respectively.
显示更多 [+] 显示较少 [-]New ternary water-soluble support from self-assembly of β-cyclodextrin-ionic liquid and an anionic polymer for a dialysis device 全文
2022
Bouyahya, Asmaa | Sembo-Backonly, Berthe-Sandra | Favrelle-Huret, Audrey | Balieu, Sébastien | Guillen, Frédéric | Mesnage, Valérie | Karakasyan-Dia, Carole | Lahcini, Mohammed | Le Cerf, Didier | Gouhier, Géraldine
We developed a new hybrid material resulting from an innovative supramolecular tripartite association between an ionic liquid covalently immobilized on primary β-cyclodextrins rim and an anionic water-soluble polymer. Two hydrophilic ternary complexes based on native and permethylated β-cyclodextrins substituted with an ionic liquid and immobilized on poly(styrene sulfonate) (CD-IL⁺PSS⁻ and CD(OMe)IL⁺PSS⁻) were obtained by simple dialysis with a cyclodextrin maximal grafting rate of 25% and 20% on the polymer, respectively. These polyelectrolytes are based on electrostatic interactions between the opposite charges of the imidazolium cation of the ionic liquid and the poly(styrene sulfonate) anion. The inclusion properties of the free cavities of the cyclodextrins and the synergic effect of the polymeric matrix were studied with three reference guests such as phenolphthalein, p-nitrophenol, and 2-anilinonaphthalene-6-sulfonic acid using UV-visible, fluorescent, and NMR spectroscopies. The support has been applied successfully in dialysis device to extract and concentrated aromatic model molecule. This simple and flexible synthetic strategy opens the way to new hybrid materials useful for fast and low-cost ecofriendly extraction techniques relevant for green analytical chemistry.
显示更多 [+] 显示较少 [-]Correlation between lung cancer markers and air pollutants in western China population 全文
2022
Long, Li | Zhu, Li-Ting | Huang, Qiansheng
The relationship between serum lung cancer markers and the air pollution remains unclear. To further reveal the correlation between air pollutants and lung cancer, a retrospective analysis of 446,032 asymptomatic healthy people and symptomatic healthy people from the Health Management Center of the First Affiliated Hospital of Chongqing Medical University from 2014 to 2019 was performed. The distribution characteristics of serum lung cancer markers, cancer embryo antigens (CEA), cytokeratin 19 fragment (CYFRA211), squamous cell carcinoma antigen (SCC), and nerve-specific enolase (NSE) was analyzed in these population. Two independent sample man-Whitney U test was used to analyze the correlation of lung cancer markers and age, and a Chi-square test was used to analyze the relationship between lung cancer markers and gender. The daily change trend was profiled for six main air quality indicators PM₁₀, PM₂.₅, SO₂, NO₂, CO, O₃ during the same period. The correlation between lung markers and air pollutants was investigated by Spearman and multiple linear regression. The results showed that CYFRA211 had the highest excess rate in the screening population. There were differences in the number of cases with concentrated expression of lung cancer markers in the different age groups. Among them, the people with NSE exceeding the standard were the youngest, and most of them were 40–55 years old. Besides SCC, the expression levels of other markers increased with age, and the expression levels of the four markers in males were significantly higher than those in females. Although the levels of PM₁₀ and PM₂.₅ exceeded the WHO standard (World Health Organization. 2011), they were not correlated with lung cancer markers. Multiple comparisons showed that the air pollutants SO₂ and CYFRA211, as well as NO₂ and NSE were closely related, but there was no significant linear relationship between CEA, SCC, and air pollutants. In conclusion, among the four lung cancer markers, CYFRA211 had the highest abnormal excess rate in total screening population, and the expression levels of these markers varied by gender and age, with males showing significantly higher expression levels than females, and they increased significantly with age except for SCC. The differential expression of these lung cancer markers may provide more strategies for lung cancer screening in the corresponding population. Lung cancer markers, CYFRA211 and NSE, can be used as sensitive biomarkers for exposure to certain air pollutants and provide references for the prevention and management of air pollution.
显示更多 [+] 显示较少 [-]Research on the spatial effects of haze pollution on public health: spatial–temporal evidence from the Yangtze River Delta urban agglomerations, China 全文
2022
Sun, Han | Yang, Xiaohui | Leng, Zhihui
Haze pollution poses a serious threat to residents’ health. In this study, a spatial econometric model of environmental health was established to investigate the direction, intensity, and spatial–temporal heterogeneity of the impact of haze pollution and its spillover effects on public health in 26 cities of the Yangtze River Delta urban agglomerations from 2005 to 2018. The study found that (1) PM₂.₅ pollution and public health level all show the characteristic of positive spatial correlation and spatial clustering. (2) Haze pollution is the main influencing factor of residents’ public health level, with significant negative effects and obvious spillover effects. The urbanization rate, the number of health technicians, and the green area per capita have significant positive impacts on public health. (3) The spatial and temporal heterogeneity of the impact of haze pollution and other factors on public health is obvious. The negative correlation between PM₂.₅ pollution and public health in eastern cities is higher than that in other cities. Both urbanization rate and green area per capita have a greater positive impact on public health in the northeast of the Yangtze River Delta region. The improvement effect of the number of health technicians on the public health is stronger in the cities of Anhui Province. The research results of this paper provide certain support for the city governments to formulate targeted policies.
显示更多 [+] 显示较少 [-]Effects of long-term exposure of norfloxacin on the HPG and HPT axes in juvenile common carp 全文
2022
Zhang, Si-Qi | Zhao, Xue-Li | He, Shu-Wen | Xing, Shao-Ying | Cao, Zhi-Han | Li, Ping | Li, Zhi-Hua
Currently, there is a relatively lack of relevant research on the interference effect of quinolone antibiotics on the endocrine of aquatic animals. In this study, the toxicity of norfloxacin (NOR) on the endocrine system of juvenile common carp (Cyprinus carpio) was evaluated, as well as the hematocyte parameters. Specifically, two important endocrine axes were assessed: the hypothalamus–pituitary–thyroid (HPT) axis and hypothalamus–pituitary–gonadal (HPG) axis. Norfloxacin was used as a representative of quinolone antibiotics. According to the concentration of water pollution areas and considering the bad situation that may be caused by wastewater discharge, a control, 100 ng/L NOR, and 1 mg/L NOR treatment groups were set up. The juvenile carp, as the test animal, was subjected to an exposure experiment for 42 days. Thyroid hormones (T3 and T4) and related genes in HPT axis and sex hormones (11-ketotestosterone [11-KT] and progesterone [PROG]) and related genes in HPG axis and blood count are tested. It was found that the T4 iodine level and conversion process were enhanced after NOR treatment, which in turn led to the increase of T3 content and biological activity in the blood. One hundred nanograms per liter NOR can inhibit the level of sex hormones and inhibit the expression of HPG axis-related genes. In the 1 mg/L NOR treatment group, long-term exposure over a certain concentration range may lead to the development of adaptive mechanisms, making the changes in hormones and related genes insignificant. In conclusion, this study provides reference data for the endocrine interference of quinolone antibiotics on aquatic organisms, and has ecological significance for assessing the health of fish populations of quinolone antibiotics. However, the specific sites and mechanisms of action related to the effects of NOR on the endocrine system remain unclear and require further study.
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