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1.
Sci Total Environ ; 922: 171149, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38402977

RESUMEN

The coupling relationship between land-use carbon emissions (LCE) and ecological environmental quality (EEQ) is critical for regional sustainable development. Rapid urbanization promotes a notable increase in LCE, which imparts significant stress on EEQ. This study used land use and cover change (LUCC) and Open-Data Inventory for Anthropogenic Carbon dioxide (ODIAC) data from the urban agglomeration in the middle reaches of the Yangtze River (UAMRYR) to evaluate LCE, applied a remote sensing ecological index (RSEI) model to calculate EEQ, and combined gravity and centroid movement trajectory models to analyze the spatiotemporal evolution characteristics of LCE and EEQ. Four-quadrant and coupling degree (CD) models were used to analyze the synergistic relationship and interaction intensity between LCE and EEQ based on three different scales of pixels, counties, and cities. The results show that: (1) LCE and EEQ exhibit clear spatial inequality distribution, and the total amount of LCE increased from 40.16 Mt. in 2000 to 131.99 Mt. in 2020; however, LCE has not yet reached peak carbon emissions. (2) From 2000 to 2020, cities with a strong correlation between LCE and EEQ showed an increasing trend, and the centroid of LCE moved sharply to Jiangxi during 2000-2005 and 2005-2010. (3) High-CD areas were primarily located in quadrant II, and low-CD areas in quadrant IV. The relationship between LCE and EEQ has improved over the past 21 years, and CD has been increasing. (4) The stability of the coupling results between LCE and EEQ was affected by different research scales; the larger the research scale is, the greater the change in the results. This study provides a scientific basis and practical scheme for LCE reduction, ecological environmental management, and regional sustainable development in the UAMRYR.

2.
Front Public Health ; 11: 1244477, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37900020

RESUMEN

Introduction: Urban green space is one of the most closely related ecosystem services to residents' lives, and it can be regarded as a preventive public health measure. Residents living in parks and other green environments can help improve their physical and mental health, reduce stress and even prevent crime and violence. Therefore, based on the actual situation in China, this paper analyzes the relationship between urban green space and the health of middle-aged and older adults and its mechanisms. Methods: This study used multiple linear regression, based the data from the China Health and Retirement Longitudinal Study (CHARLS) in 2013, 2015, and 2018, to explore the relationship between urban green space and the health of middle-aged and older adults. At the same time, group regression was conducted to identify the heterogeneity of health effects of urban green space. Results: The research shows that the increase of urban green space areas can significantly improve the health status of middle-aged and older adults. After a series of robustness tests, the results are still valid. In addition, the health effects of urban green space are different because of gender, age, education level, marital status residence, geographical location of the respondents and park quantity distribution. Further research found that reducing hot weather and optimizing air quality are the potential mechanisms of urban green space affecting the health of middle-aged and older adults, providing new evidence for the causal mechanism between urban green space and the health of middle-aged and older adults. Discussion: This study expanded the research scope of the impact of urban green space on the health of middle-aged and older adults, covering a representative sample in China. The results show that urban green space has an important impact on the health of middle-aged and older adults. Policy suggestions are made to help cities optimize the landscape and residents to enjoy ecology.


Asunto(s)
Ecosistema , Parques Recreativos , Estudios Longitudinales , Ciudades , Estado de Salud
3.
Artículo en Inglés | MEDLINE | ID: mdl-36429704

RESUMEN

This paper took the panel data of 1052 heavily-polluting listed companies from both the Shanghai and Shenzhen Stock Exchange from 2010 to 2017 to empirically analyze the impact of environmental regulation (ERG) on firm performance (FP). The article introduces a mediating effect model to test the mediating role of corporate tax burden (ETR) within the relationship between ERG on FP. The results showed that: (1) ERG has exerted a significant enhancement effect on the performance of heavily polluted firms via the ETR reduction mechanism. (2) The mediating effect of ETR depends on the duration of ERG. A significant time lag exists before the mediating effect starts to work, and the magnitude of the mediating effect increases with the time lag from the execution of the ERG. (3) The mediating effect of ETR varies significantly with the nature of corporate property rights. It is significant for the state-owned firms, while for non-state-owned firms, there is no evidence supporting the existence of the mediating effect of ETR despite ERG still having a significant direct-impact on FP. Based on these findings, we discuss the policy suggestion to optimize the impact of environmental regulation policies in terms of incentivizing the green development of polluting firms.


Asunto(s)
Política Ambiental , Organizaciones , China
4.
J Chromatogr A ; 1218(21): 3317-25, 2011 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-21036362

RESUMEN

Pyrolysis oils have attracted a lot of interest, as they are liquid energy carriers and general sources of chemicals. In this work, gas chromatography with flame ionization detector (GC-FID) and two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS) techniques were used to provide both qualitative and quantitative results of the analysis of three different pyrolysis oils. The chromatographic methods and parameters were optimized and solvent choice and separation restrictions are discussed. Pyrolysis oil samples were diluted in suitable organic solvent and were analyzed by GC×GC-TOFMS. An average of 300 compounds were detected and identified in all three samples using the ChromaToF (Leco) software. The deconvoluted spectra were compared with the NIST software library for correct matching. Group type classification was performed by use of the ChromaToF software. The quantification of 11 selected compounds was performed by means of a multiple-point external calibration curve. Afterwards, the pyrolysis oils were extracted with water, and the aqueous phase was analyzed both by GC-FID and, after proper change of solvent, by GC×GC-TOFMS. As previously, the selected compounds were quantified by both techniques, by means of multiple point external calibration curves. The parameters of the calibration curves were calculated by weighted linear regression analysis. The limit of detection, limit of quantitation and linearity range for each standard compound with each method are presented. The potency of GC×GC-TOFMS for an efficient mapping of the pyrolysis oil is undisputable, and the possibility of using it for quantification as well has been demonstrated. On the other hand, the GC-FID analysis provides reliable results that allow for a rapid screening of the pyrolysis oil. To the best of our knowledge, very few papers have been reported with quantification attempts on pyrolysis oil samples using GC×GC-TOFMS most of which make use of the internal standard method. This work provides the ground for further analysis of pyrolysis oils of diverse sources for a rational design of both their production and utilization process.


Asunto(s)
Biocombustibles/análisis , Biomasa , Cromatografía de Gases y Espectrometría de Masas/métodos , Ionización de Llama , Modelos Lineales , Compuestos Orgánicos/análisis , Compuestos Orgánicos/aislamiento & purificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
6.
Biologicals ; 33(2): 101-10, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15939288

RESUMEN

The ability of ultraviolet (UV) light to inactivate viruses is well established. However, attempts to apply this to the manufacture of pharmaceutical proteins have been limited by incomplete treatment, low capacity or excessive dilution. Effective processing of large-scale batches of UV-opaque protein solutions has been achieved using a continuous-flow device. The operation of this device has been modelled and a design equation derived to relate the processing conditions and product characteristics to the degree of virus inactivation obtained. Variables included in the model are UV-absorbance at 254 nm (A(254)), hydrodynamic properties of the protein solution, residence time, intensity of UV light and diameter and length of irradiation tube. With this information a specific constant was calculated for each virus which denotes its relative sensitivity to UV and from which the degree of virus inactivation expected can be estimated.


Asunto(s)
Proteínas , Soluciones , Rayos Ultravioleta , Inactivación de Virus , Espectrofotometría Ultravioleta
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