This study aims to investigate the influence of rapid economic development on pollution at the municipal level in China.It constructs a Stochastic Impacts by Regression on Population,Affluence and Technology model(STI...This study aims to investigate the influence of rapid economic development on pollution at the municipal level in China.It constructs a Stochastic Impacts by Regression on Population,Affluence and Technology model(STIRPAT model) and uses comprehensive municipal data on industrial pollution and economic performance.The dataset contains 290 cities from2003 to 2016 as a sample for the panel data analysis.The study further separates the cities into two groups by their levels of economic development for heterogeneity analysis.It reveals that a low level of economic development would aggravate environmental pollution,and when the economy reaches a high level,this economic development will improve environmental quality.We also find that the relationships between foreign direct investment and industrial dust and sulfur dioxide(SO_2) discharge are significant,while the relationship between economic growth and effluent emission is not.The more developed subsample cities present an inverted U-shaped curve between industrial pollutant emission,GDP per capita,and foreign direct investment,while the less developed subsamples show no such relationship.Since the shape of these curves differs among regions,their turning points vary accordingly.Based on this finding,this study suggests that the governments of more developed cities should balance environmental pollution and economic development by enhancing environmental regulations and adjusting industrial structure.展开更多
This paper concentrates on the dynamics of a waterborne pathogen periodic PDE model with environmental pollution.For this model,we derive the basic reproduction number R0and establish a threshold type result on its gl...This paper concentrates on the dynamics of a waterborne pathogen periodic PDE model with environmental pollution.For this model,we derive the basic reproduction number R0and establish a threshold type result on its global dynamics in terms of R0,which predicts the extinction or persistence of diseases.More precisely,the disease-free steady state is globally attractive if R_(0)<1,while the system admits at least one positive periodic solution and the disease is uniformly persistent if R_(0)>1.Moreover,we carry out some numerical simulations to illustrate the long-term behaviors of solutions and explore the influence of environmental pollution and seasonality on the spread of waterborne diseases.展开更多
In this paper, we present simultaneous multiple pollutant gases （CO2, CO, and NO） measurements by using the non-dispersive infrared （NDIR） technique. A cross-correlation correction method is proposed and used to c...In this paper, we present simultaneous multiple pollutant gases （CO2, CO, and NO） measurements by using the non-dispersive infrared （NDIR） technique. A cross-correlation correction method is proposed and used to correct the cross-interferences among the target gases. The calculation of calibration curves is based on least-square fittings with third-order polynomials, and the interference functions are approximated by linear curves. The pure absorbance of each gas is obtained by solving three simultaneous equations using the fitted interference functions. Through the interference correction, the signal created at each filter channel only depends on the absorption of the intended gas. Gas mixture samples with different concentrations of CO2, CO, and NO are pumped into the sample cell for analysis. The results show that the measurement error of each gas is less than 4.5%.展开更多
In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towa...In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towards divalent metals(Pb 2+,Mn 2+,and Zn 2+) in ethanol solution has been studies by a batch technique.The ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen adsorption-desorption.The Langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption intensity.In aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were observed.The maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb 2+ /beryl and Pb 2+ /tourmaline,respectively.The energetic effects caused by metal cations adsorption were determined through calorimetric titrations.Thermodynamics indicated the existence of favorable conditions for such Pb 2+-,Mn 2+-,and Zn 2+-OH interactions.展开更多
基金financially supported by the Major Program of National Social Science Foundation (No.16ZDA006)National Natural Science Foundation of China (Nos.71603193 and 71974151)Teaching and Research Project of Wuhan University (No.1201-413200127)。
文摘This study aims to investigate the influence of rapid economic development on pollution at the municipal level in China.It constructs a Stochastic Impacts by Regression on Population,Affluence and Technology model(STIRPAT model) and uses comprehensive municipal data on industrial pollution and economic performance.The dataset contains 290 cities from2003 to 2016 as a sample for the panel data analysis.The study further separates the cities into two groups by their levels of economic development for heterogeneity analysis.It reveals that a low level of economic development would aggravate environmental pollution,and when the economy reaches a high level,this economic development will improve environmental quality.We also find that the relationships between foreign direct investment and industrial dust and sulfur dioxide(SO_2) discharge are significant,while the relationship between economic growth and effluent emission is not.The more developed subsample cities present an inverted U-shaped curve between industrial pollutant emission,GDP per capita,and foreign direct investment,while the less developed subsamples show no such relationship.Since the shape of these curves differs among regions,their turning points vary accordingly.Based on this finding,this study suggests that the governments of more developed cities should balance environmental pollution and economic development by enhancing environmental regulations and adjusting industrial structure.
基金supported by the NSFC(12161079)the XSTP(KC2023058)。
文摘This paper concentrates on the dynamics of a waterborne pathogen periodic PDE model with environmental pollution.For this model,we derive the basic reproduction number R0and establish a threshold type result on its global dynamics in terms of R0,which predicts the extinction or persistence of diseases.More precisely,the disease-free steady state is globally attractive if R_(0)<1,while the system admits at least one positive periodic solution and the disease is uniformly persistent if R_(0)>1.Moreover,we carry out some numerical simulations to illustrate the long-term behaviors of solutions and explore the influence of environmental pollution and seasonality on the spread of waterborne diseases.
基金Project supported by the National High Technology Research and Development Program of China (Grant No. 2009AA063006)the National Natural Science Foundation of China (Grant No. 40805015)the Excellent Youth Scientific Foundation of Anhui Province, China (Grant No. 10040606Y28)
文摘In this paper, we present simultaneous multiple pollutant gases （CO2, CO, and NO） measurements by using the non-dispersive infrared （NDIR） technique. A cross-correlation correction method is proposed and used to correct the cross-interferences among the target gases. The calculation of calibration curves is based on least-square fittings with third-order polynomials, and the interference functions are approximated by linear curves. The pure absorbance of each gas is obtained by solving three simultaneous equations using the fitted interference functions. Through the interference correction, the signal created at each filter channel only depends on the absorption of the intended gas. Gas mixture samples with different concentrations of CO2, CO, and NO are pumped into the sample cell for analysis. The results show that the measurement error of each gas is less than 4.5%.
基金The authors are indebted to CNPq for fellowships and CAPES for financial support
文摘In this study,the original tourmaline and beryl mineral samples have been collected from a Brazilian pegmatite.The objective of this study was to examine the adsorption behavior of Brazilian ciclosilicate samples,towards divalent metals(Pb 2+,Mn 2+,and Zn 2+) in ethanol solution has been studies by a batch technique.The ciclosilicate samples were characterized by elemental analysis,Fourier transform infrared spectroscopy,helium picnometry,mercury porosity,and nitrogen adsorption-desorption.The Langmuir expression for adsorption isotherm was applied in order to determine the adsorption capacity to form a monolayer and the constant related to the adsorption intensity.In aqueous solution there was a significant adsorption increase with the temperature and pronounced synergistic effects were observed.The maximum number of moles adsorbed was determined to be 12.48 and 11.49 mmol/g for systems Pb 2+ /beryl and Pb 2+ /tourmaline,respectively.The energetic effects caused by metal cations adsorption were determined through calorimetric titrations.Thermodynamics indicated the existence of favorable conditions for such Pb 2+-,Mn 2+-,and Zn 2+-OH interactions.
