The Normal Chlorine Content of Surface Waters of Western Florida

1915 ◽  
Vol 7 (4) ◽  
pp. 357-358
Author(s):  
C Brautlecht ◽  
B Langley
Keyword(s):  
Surface Waters ◽  
Chlorine Content

scholarly journals Photochemical Degradation of Short-Chain Chlorinated Paraffins in Aqueous Solution by Hydrated Electrons and Hydroxyl Radicals

2022 ◽  
Author(s):  
Brian DiMento ◽  
Cristina Tusei ◽  
Christoph Aeppli
Keyword(s):  
Organic Pollutants ◽  
Hydroxyl Radicals ◽  
Surface Waters ◽  
Rate Constants ◽  
Degradation Rate ◽  
Chlorine Content ◽  
Photochemical Degradation ◽  
Model Compounds ◽  
Chlorinated Paraffins ◽  
Hydrated Electrons

Short-chain chlorinated paraffins (SCCPs) are a complex mixture of polychlorinated alkanes (C10-C13, chlorine content 40-70%), and have been categorized as persistent organic pollutants. However, there are knowledge gaps about their environmental degradation, particularly the effectiveness and mechanism of photochemical degradation in surface waters. Photochemically-produced hydrated electrons (e-(aq)) have been shown to degrade highly chlorinated compounds in environmentally-relevant conditions more effectively than hydroxyl radicals (·OH), which can degrade a wide range of organic pollutants. This study aimed to evaluate the potential for e-(aq) and ·OH to degrade SCCPs. To this end, the degradation of SCCP model compounds was investigated under laboratory conditions that photochemically produced e-(aq) or ·OH. Resulting SCCP degradation rate constants for e-(aq) were on the same order of magnitude as well-known chlorinated pesticides. Experiments in the presence of ·OH yielded similar or higher second-order rate constants. Trends in e-(aq) and ·OH SCCP model compounds degradation rate constants of the investigated SCCPs were consistent with that of other chlorinated compounds, with higher chlorine content producing in higher rate constants for e-(aq) and lower for ·OH. Above a chlorine:carbon ratio of approximately 0.6, the e-(aq) second-order rate constants were higher than rate constants for ·OH reactions. Results of this study furthermore suggest that SCCPs are likely susceptible to photochemical degradation in sunlit surface waters, facilitated by dissolved organic matter that can produce e-(aq) and ·OH when irradiated.

scholarly journals The Influence of Ocean Spindrift and Blown Spary on the Chlorine Content of Inland Ground Waters

1914 ◽  
Vol 14 (1) ◽  
pp. 119-128
Author(s):  
William Barr
Keyword(s):  
Public Health ◽  
Water Analysis ◽  
Surface Waters ◽  
Chlorine Content ◽  
Ground Waters ◽  
Common Observation

In works on Public Health and Water Analysis, it is a common observation that the amount of chlorine in inland surface waters near the seaboard is considerably higher than what obtains in samples from more inland parts.

scholarly journals Photochemical Degradation of Short-Chain Chlorinated Paraffins in Aqueous Solution by Hydrated Electrons and Hydroxyl Radicals

2020 ◽  
Author(s):  
Brian DiMento ◽  
Cristina Tusei ◽  
Christoph Aeppli
Keyword(s):  
Organic Pollutants ◽  
Hydroxyl Radicals ◽  
Surface Waters ◽  
Rate Constants ◽  
Chlorine Content ◽  
Short Chain ◽  
Photochemical Degradation ◽  
Chlorinated Paraffins ◽  
Wide Range ◽  
Hydrated Electrons

<p>Short-chain chlorinated paraffins (SCCPs) are a complex mixture of polychlorinated alkanes (C10-C13, chlorine content 40-70%). While these compounds are categorized as persistent organic pollutants, there are knowledge gaps about their environmental degradation, particularly the effectiveness and mechanism of photochemical degradation in surface waters. Photochemically-produced hydrated electrons (e-(aq)) have been shown to degrade highly chlorinated compounds in environmentally-relevant conditions more effectively than hydroxyl radicals (·OH), which can degrade a wide range of organic pollutants. This study aimed to evaluate the potential for e-(aq) to degrade SCCPs, and compare this reaction to ·OH-mediated degradation. To this end, the degradation of SCCP model compounds was investigated under laboratory conditions that photochemically produced e-(aq) or ·OH. Resulting SCCP degradation rate constants for e-(aq) were on the same order of magnitude as well-known chlorinated pesticides. Experiments in the presence of ·OH yielded similar or higher second-order rate constants. By compiling literature data for a wide range of chlorinated compounds, it was found that higher chlorine content results in higher rate constants for e-(aq) and lower for ·OH. Above a composition of approximately 60 % Cl, the e-(aq) second-order rate constants were higher than rate constants for ·OH reactions. The results of this study imply that SCCPs are susceptible to photochemical degradation in the environment, facilitated by dissolved organic matter and other sources of reactive intermediates in sunlit surface waters.<br></p>

scholarly journals Photochemical Degradation of Short-Chain Chlorinated Paraffins in Aqueous Solution by Hydrated Electrons and Hydroxyl Radicals

2020 ◽  
Author(s):  
Brian DiMento ◽  
Cristina Tusei ◽  
Christoph Aeppli
Keyword(s):  
Organic Pollutants ◽  
Hydroxyl Radicals ◽  
Surface Waters ◽  
Rate Constants ◽  
Chlorine Content ◽  
Short Chain ◽  
Photochemical Degradation ◽  
Chlorinated Paraffins ◽  
Wide Range ◽  
Hydrated Electrons

<p>Short-chain chlorinated paraffins (SCCPs) are a complex mixture of polychlorinated alkanes (C10-C13, chlorine content 40-70%). While these compounds are categorized as persistent organic pollutants, there are knowledge gaps about their environmental degradation, particularly the effectiveness and mechanism of photochemical degradation in surface waters. Photochemically-produced hydrated electrons (e-(aq)) have been shown to degrade highly chlorinated compounds in environmentally-relevant conditions more effectively than hydroxyl radicals (·OH), which can degrade a wide range of organic pollutants. This study aimed to evaluate the potential for e-(aq) to degrade SCCPs, and compare this reaction to ·OH-mediated degradation. To this end, the degradation of SCCP model compounds was investigated under laboratory conditions that photochemically produced e-(aq) or ·OH. Resulting SCCP degradation rate constants for e-(aq) were on the same order of magnitude as well-known chlorinated pesticides. Experiments in the presence of ·OH yielded similar or higher second-order rate constants. By compiling literature data for a wide range of chlorinated compounds, it was found that higher chlorine content results in higher rate constants for e-(aq) and lower for ·OH. Above a composition of approximately 60 % Cl, the e-(aq) second-order rate constants were higher than rate constants for ·OH reactions. The results of this study imply that SCCPs are susceptible to photochemical degradation in the environment, facilitated by dissolved organic matter and other sources of reactive intermediates in sunlit surface waters.<br></p>

Habitat Association of Klebsiella Species

1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley
Keyword(s):  
Drinking Water ◽  
Gastrointestinal Tract ◽  
Surface Waters ◽  
Industrial Effluents ◽  
Opportunistic Pathogen ◽  
Habitat Associations ◽  
Habitat Association ◽  
Klebsiella Species ◽  
Almost All ◽  
Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

Identifying Sources of Sulfate Aerosols Reaching Whiteface Mountain, NY

1985 ◽  
Vol 43 ◽  
pp. 98-101
Author(s):  
James S. Webber
Keyword(s):  
Trace Metals ◽  
Acid Deposition ◽  
Surface Waters ◽  
Dry Deposition ◽  
Coal Combustion ◽  
Public Awareness ◽  
Sulfate Aerosols ◽  
Wet And Dry Deposition ◽  
Whiteface Mountain ◽  
Toxic Trace Metals

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.

Sign in / Sign up

Export Citation Format

Share Document