Cumulative inhalation of respirable coal mine dust(RCMD)can lead to severe lung diseases,including coal worker's pneu-moconiosis(CWP),silicosis,mixed dust pneumoconiosis,dust-related diffuse fibrosis(DDF),and prog...Cumulative inhalation of respirable coal mine dust(RCMD)can lead to severe lung diseases,including coal worker's pneu-moconiosis(CWP),silicosis,mixed dust pneumoconiosis,dust-related diffuse fibrosis(DDF),and progressive massive fibrosis(PMF).Statistics from the number of reported cases showed a significant decrease in the progression of respiratory diseases in the 1990s.However,an unexpected increase in the number of CWP cases was reported in the late 1990s.To date,there has been no comprehensive systematic review to assess all contributing factors to the resurgence of CWP cases.This study aims to investigate the effects of various mining parameters on the prevalence of CWP in coal mines.A systematic review using the preferred reporting items for systematic reviews and meta-analysis(PRISMA)method was conducted to investigate the health effects of RCMD exposure and identify the factors that may contribute to the recent resurgence of CWP cases.The systematic review yielded a total of 401 papers,which were added to the database.The total number of 148 and 208 papers were excluded from the database in the process of screening and eligibility,respectively.Then,18 papers were considered for data selection and full-text assessment.The review revealed that factors including geographic location,mine size,mining operation type,coal-seam thickness,coal rank,changes in mining practices,technology advancement,and engi-neering dust control practices are contributing to the recent resurgence of CWP among coal workers.However,the evidence for root causes is limited owing to the methodological constraints of the studies;therefore,further detailed studies are needed.展开更多
In the United States,an unexpected and severe increase in coal miners’lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence.This study aims to scrutinize the effects...In the United States,an unexpected and severe increase in coal miners’lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence.This study aims to scrutinize the effects of various mining parameters,including coal rank,mine size,mine operation type,coal seam height,and geographical location on the prevalence of coal worker’s pneumoconiosis(CWP)in surface and underground coal mines.A comprehensive dataset was created using the U.S.Mine Safety and Health Administration(MSHA)Employment and Accident/Injury databases.The information was merged based on the mine ID by utilizing SQL data management software.A total number of 123,589 mine-year observations were included in the statistical analysis.Generalized Estimating Equation(GEE)model was used to conduct a statistical analysis on a total of 29,707,and 32,643 mine-year observations for underground and surface coal mines,respectively.The results of the econometrics approach revealed that coal workers in underground coal mines are at a greater risk of CWP comparing to those of surface coal operations.Furthermore,underground coal mines in the Appalachia and Interior regions are at a higher risk of CWP prevalence than the Western region.Surface coal mines in the Appalachian coal region are more likely to CWP development than miners in the Western region.The analysis also indicated that coal workers working in smaller mines are more vulnerable to CWP than those in large mine sizes.Furthermore,coal workers in thin-seam underground mine operations are more likely to develop CWP.展开更多
A simple and selective method using a column packed with graphene oxide（GO） as a solid phase extractant has been developed for the multi-element preconcentration of Fe（Ⅲ）,Ni（Ⅱ）,Cu（Ⅱ） and Zn（Ⅱ）ions prior ...A simple and selective method using a column packed with graphene oxide（GO） as a solid phase extractant has been developed for the multi-element preconcentration of Fe（Ⅲ）,Ni（Ⅱ）,Cu（Ⅱ） and Zn（Ⅱ）ions prior to flame atomic absorption spectrometric determinations.The method is based on the sorption of mentioned ions on synthesized GO using 2-（tert-butoxy）-N-（3-carbamothioylphenyl）acetamide as a chelating agent.Several parameters on the extraction and complex formation were optimized.Under the optimized conditions（pH 6,flow rate 9 mL/min）,metal ions were retained on the column,then quantitatively eluted by HNO3solution（5 mL,3.0 mol/L）.The preconcentration factor was calculated as250.The detection limits for the analyte ions of interest were found in the range of 0.11 ng/mL（Ni2＋） to0.63 ng/mL（Cu2＋）.The column packed with GO was adequate for metal ions separation in matrixes containing alkali,alkaline earth,transition and heavy metal ions.展开更多
This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and ...This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and inexpensive manner.More than 10 anthracite-associated samples were collected from each of three Pennsylvanian sites(sites B,J and C)based on Thorium gamma ray logging suggesting high REY content.Several samples from each site were analyzed by ICP-MS to determine the rare earth distribution patterns and to establish the site-specific linear equations of Y and REY.The Y contents of the remaining samples were measured by a portable X-ray fluorescence analyzer,and the REY values were estimated based on the site-specific linear equation developed earlier.R-squared values above 0.70 were obtained for all the estimation equations from all three sites on both a whole sample basis and an ash basis.Previously,ash content has been widely used as an indicator of high REY content.This may not be applicable for a specific site.Site B in this study is an example where ash contents could not be statistically correlated with REY,so using Y for estimation is more applicable.The demonstrated sample screening process is suitable for samples from sites that share more similar distribution patterns(either MREY or LREY or HREY)as well as for samples from sites that share multiple distribution patterns(LREY/MREY/HREY)depending on the desirable accuracy.The demonstrated process lowers the analytical cost from$70 to 80 dollars per sample to$10-15 per sample while significantly reducing the processing time and acid consumption for ICP digestion.This is particularly true when a relatively large sample size is involved,for example,100 samples from one site analyzed by ICP-MS/OES.展开更多
The green transition’s push for electrification has substantially increased the demand for copper,making it a critical raw material.This extravagant demand has made it profitable to extract copper from low-grade sulf...The green transition’s push for electrification has substantially increased the demand for copper,making it a critical raw material.This extravagant demand has made it profitable to extract copper from low-grade sulfide ores,which contain less than 0.3wt%copper.However,processing such low-grade ores requires extensive amounts of chemicals,raising environmental concerns.Thus,several investigations have been conducted on non-traditional lixiviants for copper extraction.Surprisingly,few studies have comprehensively reviewed this area to provide a comprehensive understanding and highlight gaps.This review analyzes investigations that have worked on the leaching process of copper into solutions using environmentally friendly reagents,particularly organic acids and amino acids,and compare them to conventional inorganic acids and examines recent advancements in ecofriendly leaching agents,specifically their application in copper leaching.The primary objective is to highlight the significance of these green reagents in mobilizing copper from solid to solution phases.It was highlighted that factors,such as mineralogy,mechanical activation,impurities,particle size,temperature,and initial concentration of the leaching agent,influence the leaching efficiency of organic and amino acids from primary and secondary copper resources.These variables interact in more complex ways than those encountered with conventional leaching methods.Research in this area has shown promising results,both in terms of extraction efficiency and reduced environmental impact,making it an exciting and essential area for further exploration and development.This shift towards using nonconventional lixiviants represents a significant step forward in the quest for more sustainable and environmentally responsible mining practices and recycling processes.展开更多
基金funded by the National Institute for Occupational Safety and Health (NIOSH) (75D30119C06390).
文摘Cumulative inhalation of respirable coal mine dust(RCMD)can lead to severe lung diseases,including coal worker's pneu-moconiosis(CWP),silicosis,mixed dust pneumoconiosis,dust-related diffuse fibrosis(DDF),and progressive massive fibrosis(PMF).Statistics from the number of reported cases showed a significant decrease in the progression of respiratory diseases in the 1990s.However,an unexpected increase in the number of CWP cases was reported in the late 1990s.To date,there has been no comprehensive systematic review to assess all contributing factors to the resurgence of CWP cases.This study aims to investigate the effects of various mining parameters on the prevalence of CWP in coal mines.A systematic review using the preferred reporting items for systematic reviews and meta-analysis(PRISMA)method was conducted to investigate the health effects of RCMD exposure and identify the factors that may contribute to the recent resurgence of CWP cases.The systematic review yielded a total of 401 papers,which were added to the database.The total number of 148 and 208 papers were excluded from the database in the process of screening and eligibility,respectively.Then,18 papers were considered for data selection and full-text assessment.The review revealed that factors including geographic location,mine size,mining operation type,coal-seam thickness,coal rank,changes in mining practices,technology advancement,and engi-neering dust control practices are contributing to the recent resurgence of CWP among coal workers.However,the evidence for root causes is limited owing to the methodological constraints of the studies;therefore,further detailed studies are needed.
基金This study is funded by the National Institute for Occupational Safety and Health(NIOSH)[75D30119C06390].The authors would like to thank Dr.Arvin Ebrahimkhanlou for all precise technical comments related to statistical analysis.
文摘In the United States,an unexpected and severe increase in coal miners’lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence.This study aims to scrutinize the effects of various mining parameters,including coal rank,mine size,mine operation type,coal seam height,and geographical location on the prevalence of coal worker’s pneumoconiosis(CWP)in surface and underground coal mines.A comprehensive dataset was created using the U.S.Mine Safety and Health Administration(MSHA)Employment and Accident/Injury databases.The information was merged based on the mine ID by utilizing SQL data management software.A total number of 123,589 mine-year observations were included in the statistical analysis.Generalized Estimating Equation(GEE)model was used to conduct a statistical analysis on a total of 29,707,and 32,643 mine-year observations for underground and surface coal mines,respectively.The results of the econometrics approach revealed that coal workers in underground coal mines are at a greater risk of CWP comparing to those of surface coal operations.Furthermore,underground coal mines in the Appalachia and Interior regions are at a higher risk of CWP prevalence than the Western region.Surface coal mines in the Appalachian coal region are more likely to CWP development than miners in the Western region.The analysis also indicated that coal workers working in smaller mines are more vulnerable to CWP than those in large mine sizes.Furthermore,coal workers in thin-seam underground mine operations are more likely to develop CWP.
文摘A simple and selective method using a column packed with graphene oxide（GO） as a solid phase extractant has been developed for the multi-element preconcentration of Fe（Ⅲ）,Ni（Ⅱ）,Cu（Ⅱ） and Zn（Ⅱ）ions prior to flame atomic absorption spectrometric determinations.The method is based on the sorption of mentioned ions on synthesized GO using 2-（tert-butoxy）-N-（3-carbamothioylphenyl）acetamide as a chelating agent.Several parameters on the extraction and complex formation were optimized.Under the optimized conditions（pH 6,flow rate 9 mL/min）,metal ions were retained on the column,then quantitatively eluted by HNO3solution（5 mL,3.0 mol/L）.The preconcentration factor was calculated as250.The detection limits for the analyte ions of interest were found in the range of 0.11 ng/mL（Ni2＋） to0.63 ng/mL（Cu2＋）.The column packed with GO was adequate for metal ions separation in matrixes containing alkali,alkaline earth,transition and heavy metal ions.
基金the Department of Energy[Grant Number DE-FE-0030146]。
文摘This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and inexpensive manner.More than 10 anthracite-associated samples were collected from each of three Pennsylvanian sites(sites B,J and C)based on Thorium gamma ray logging suggesting high REY content.Several samples from each site were analyzed by ICP-MS to determine the rare earth distribution patterns and to establish the site-specific linear equations of Y and REY.The Y contents of the remaining samples were measured by a portable X-ray fluorescence analyzer,and the REY values were estimated based on the site-specific linear equation developed earlier.R-squared values above 0.70 were obtained for all the estimation equations from all three sites on both a whole sample basis and an ash basis.Previously,ash content has been widely used as an indicator of high REY content.This may not be applicable for a specific site.Site B in this study is an example where ash contents could not be statistically correlated with REY,so using Y for estimation is more applicable.The demonstrated sample screening process is suitable for samples from sites that share more similar distribution patterns(either MREY or LREY or HREY)as well as for samples from sites that share multiple distribution patterns(LREY/MREY/HREY)depending on the desirable accuracy.The demonstrated process lowers the analytical cost from$70 to 80 dollars per sample to$10-15 per sample while significantly reducing the processing time and acid consumption for ICP digestion.This is particularly true when a relatively large sample size is involved,for example,100 samples from one site analyzed by ICP-MS/OES.
文摘The green transition’s push for electrification has substantially increased the demand for copper,making it a critical raw material.This extravagant demand has made it profitable to extract copper from low-grade sulfide ores,which contain less than 0.3wt%copper.However,processing such low-grade ores requires extensive amounts of chemicals,raising environmental concerns.Thus,several investigations have been conducted on non-traditional lixiviants for copper extraction.Surprisingly,few studies have comprehensively reviewed this area to provide a comprehensive understanding and highlight gaps.This review analyzes investigations that have worked on the leaching process of copper into solutions using environmentally friendly reagents,particularly organic acids and amino acids,and compare them to conventional inorganic acids and examines recent advancements in ecofriendly leaching agents,specifically their application in copper leaching.The primary objective is to highlight the significance of these green reagents in mobilizing copper from solid to solution phases.It was highlighted that factors,such as mineralogy,mechanical activation,impurities,particle size,temperature,and initial concentration of the leaching agent,influence the leaching efficiency of organic and amino acids from primary and secondary copper resources.These variables interact in more complex ways than those encountered with conventional leaching methods.Research in this area has shown promising results,both in terms of extraction efficiency and reduced environmental impact,making it an exciting and essential area for further exploration and development.This shift towards using nonconventional lixiviants represents a significant step forward in the quest for more sustainable and environmentally responsible mining practices and recycling processes.
