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J.d. Noll - One of the best experts on this subject based on the ideXlab platform.
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High-sensitivity cassette for reducing limit of detection for Diesel Particulate Matter sampling
Environmental Monitoring and Assessment, 2020Co-Authors: J.d. Noll, S. Vanderslice, A. Bugarski, J. HummerAbstract:NIOSH researchers designed a high-sensitivity (HS) cassette to improve the limit of detection of the National Institute for Occupational Safety and Health’s (NIOSH) method 5040 and the Airtec near real-time Diesel Particulate Matter (DPM) monitor. This was achieved by reducing the size of the Diesel Particulate Matter deposition spot from 8.0 cm^2 (NIOSH method 5040 mining samples) and 7.6 cm^2 (Airtec samples) to 0.5 cm^2. When compared with the standard cassette, the new high-sensitivity cassette improves the limit of detection of NIOSH method 5040 by approximately five times, and the differences between the elemental carbon results from the HS cassette and the standard three-piece cassette were within statistical error. The limit of detection for Airtec measurements improved by approximately 15 times, and the elemental carbon results with the HS cassette between the Airtec and NIOSH method 5040 were within statistical agreement. When used in the Airtec monitor, the high-sensitivity cassette showed promise for measuring short-duration spot checks of ambient concentrations but was limited when performing some long-term sampling due to the resultant loss of dynamic range. Only up to 7 μg of elemental carbon was collected onto the HS cassette before the increase in pump backpressure caused the flow fluctuations to exceed targeted values by unacceptable levels. The HS cassette shows promise for effective engineering evaluations of control technologies and strategies and near real-time Diesel Particulate Matter measurements for a variety of occupations.
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Evaluation of a wearable monitor for measuring real-time Diesel Particulate Matter concentrations in several underground mines.
Journal of occupational and environmental hygiene, 2013Co-Authors: J.d. Noll, Samuel J. JaniskoAbstract:The standard method for determining Diesel Particulate Matter (DPM) exposures in underground metal/nonmetal mines provides the average exposure concentration for an entire working shift, and it can take weeks to obtain results. This approach is problematic because, although it reports that an overexposure has occurred, it fails to provide critical information about cause or prevention. Conversely, real-time measurement would provide miners with timely information to identify the major factors contributing to overexposures and would allow engineering controls to be deployed immediately. Due to these potential benefits, the National Institute for Occupational Safety and Health (NIOSH) developed a wearable instrument that measures real-time elemental carbon (EC) concentrations (EC is a DPM surrogate) via laser extinction. This instrument was later constructed into a commercial version (Airtec). This article evaluates the Airtec's performance in several underground metal/nonmetal mines by comparing it to the ...
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Effects of sampling artifacts on occupational samples of Diesel Particulate Matter.
Environmental science & technology, 2008Co-Authors: J.d. Noll, M. Eileen BirchAbstract:Total carbon (TC) is sometimes used to measure or characterize Diesel Particulate Matter (DPM) in occupational settings such as underground mines. DPM samples are collected on quartz fiber filters....
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Using laser absorption techniques to monitor Diesel Particulate Matter exposure in underground stone mines
Smart Biomedical and Physiological Sensor Technology V, 2007Co-Authors: J.d. Noll, Samuel J. JaniskoAbstract:Underground miners are exposed to some of the highest levels of Diesel Particulate Matter (DPM) in the United States. Therefore, it is important to monitor the exposure of miners to DPM, but it can be difficult because of the complex composition of DPM and the number of interferences. Currently, elemental carbon (EC) is used as a surrogate because it makes up a significant fraction of the DPM and is not affected by interferences. Standard measurement methods for EC can be time consuming and only record end of shift results. In this research, a laser absorption technique that enables one to measure EC concentration in near real time was shown to be a beneficial tool. The real time data showed that the fresh air being drawn into a stone mine was not properly reaching the working area and needed to be redirected to decrease DPM concentrations. The real time data also provided a more accurate efficiency of an environmental cab compared to just using the standard method by detecting the opening of the cab’s window and door. The EC optical monitor was also worn by researchers in a mine to show how it can give not only the average concentration for the shift but also reveal when and where a miner is exposed to DPM.
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relationship between elemental carbon total carbon and Diesel Particulate Matter in several underground metal non metal mines
Environmental Science & Technology, 2007Co-Authors: J.d. Noll, Steven E. Mischler, L. D. Patts, A. D. Bugarski, Linda McwilliamsAbstract:Elemental carbon (EC) is currently used as a surrogate for Diesel Particulate Matter (DPM) in underground mines since it can be accurately measured at low concentrations and Diesels are the only source of submicrometer EC in underground mines. A disadvantage of using EC as a surrogate for DPM is that the fraction of EC in DPM is a function of various engine parameters and fuel formulations, etc. In order to evaluate how EC predicts DPM in the underground mining atmosphere, measurements of total carbon (TC; representing over 80% of the DPM) and EC were taken away from potential interferences in four underground metal/non-metal mines during actual production. In a controlled atmosphere, DPM mass, TC, and EC measurements were also collected while several different types of vehicles simulated production with and without different types of control technologies. When Diesel Particulate filters (DPFs) were not used, both studies showed that EC could be used to predict DPM mass or TC. The variability of the data ...
J L G Fierro - One of the best experts on this subject based on the ideXlab platform.
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au0 au3 bifunctional site mediated enhanced catalytic activity of au zno composite in Diesel Particulate Matter oxidation
Journal of Catalysis, 2017Co-Authors: Grisel Corro, Surinam Cebada, U Pal, J L G FierroAbstract:Abstract Hydrogen-reduced air-calcined 1%Au/ZnO composite synthesized by gold impregnation in ZnO has been utilized as catalyst for Diesel Particulate Matter (DPM) oxidation. The catalyst was characterized by UV-vis optical absorption, X-ray photoelectron spectroscopy and transmission electronic microscopy. The composite catalyst showed excellent activity for the oxidation of DPM at temperature as low as 230 °C. The activity of the catalyst does not change up to 6 oxidation cycles. The high catalytic activity of the composite has been attributed to the formation of stable Au 0 –Au 3+ bifunctional catalytic sites at the gold-ZnO interface, which enhances the contact efficiency of solid Particulate Matter on Au 3+ and the generation of superoxide species on Au 0 . The high stability of the bifunctional Au 0 -Au 3+ sites is associated with the electronic interactions between gold and n-type semiconductor ZnO at their interface.
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Au0–Au3+ bifunctional site mediated enhanced catalytic activity of Au/ZnO composite in Diesel Particulate Matter oxidation
Journal of Catalysis, 2017Co-Authors: Grisel Corro, Surinam Cebada, Umapada Pal, J L G FierroAbstract:Abstract Hydrogen-reduced air-calcined 1%Au/ZnO composite synthesized by gold impregnation in ZnO has been utilized as catalyst for Diesel Particulate Matter (DPM) oxidation. The catalyst was characterized by UV-vis optical absorption, X-ray photoelectron spectroscopy and transmission electronic microscopy. The composite catalyst showed excellent activity for the oxidation of DPM at temperature as low as 230 °C. The activity of the catalyst does not change up to 6 oxidation cycles. The high catalytic activity of the composite has been attributed to the formation of stable Au 0 –Au 3+ bifunctional catalytic sites at the gold-ZnO interface, which enhances the contact efficiency of solid Particulate Matter on Au 3+ and the generation of superoxide species on Au 0 . The high stability of the bifunctional Au 0 -Au 3+ sites is associated with the electronic interactions between gold and n-type semiconductor ZnO at their interface.
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Low Cost Cu/ZnO as Low Temperature (150 °C) Catalyst for Diesel Particulate Matter Oxidation
Topics in Catalysis, 2016Co-Authors: Grisel Corro, Surinam Cebada, J L G Fierro, Fortino Bañuelos, Umapada Pal, Emmanuel GuilleminotAbstract:The catalytic behavior of hydrogen-reduced copper loaded ZnO, SiO2, and TiO2 has been investigated for Diesel Particulate Matter(PM) oxidation. 5 %Cu/ZnO showed a strong Diesel PM oxidation activity at 150 °C. XPS spectroscopy was utilized to study the electronic states of Cu in Cu/ZnO catalyst. Presence of Cu1+ ions at the surface of the catalyst even after its use in PM oxidation cycles was assigned responsible for its high catalytic performance. The high stability of Cu1+ is explained on basis of the isoelectronic interactions of Cu1+ (3d10) with Zn2+ (3d10) at the Cu2O–ZnO interface. Cu/SiO2 and Cu/TiO2 were not active for this reaction probably due to the absence of Cu1+ which could not be stabilized by Ti4+ or Si4+. Results indicate that 5 %Cu/ZnO catalyst can be utilized for the abatement of Diesel engine emissions even from the starting point of cold engines.
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hydrogen reduced cu zno composite as efficient reusable catalyst for Diesel Particulate Matter oxidation
Applied Catalysis B-environmental, 2015Co-Authors: Grisel Corro, Surinam Cebada, U Pal, J L G Fierro, Josefina AlvaradoAbstract:Abstract Hydrogen-reduced copper-loaded ZnO (Cu/ZnO) showed a strong Diesel Particulate Matter oxidation activity at temperature as low as 150 °C. Cu/ZnO catalyst with 5% nominal Cu content was tested for the oxidation of Diesel Particulate Matter under air flow between 25 and 800 °C. The high catalytic performance of reduced 5%Cu/ZnO even after its use in Diesel Particulate Matter oxidation has been assigned to the presence of Cu 1+ ions at its surface, determined by Auger electronic spectroscopy. The high stability of Cu 1+ could be assigned to the isoelectronic interaction of Cu 1+ (3d 10 ) with Zn 2+ (3d 10 ) at the Cu 2 O–ZnO interface. Results presented in this work indicate that the composite catalyst can be considered as part of an exhaust catalytic system, for abating Diesel Particulate Matter emission at low temperature.
Grisel Corro - One of the best experts on this subject based on the ideXlab platform.
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au0 au3 bifunctional site mediated enhanced catalytic activity of au zno composite in Diesel Particulate Matter oxidation
Journal of Catalysis, 2017Co-Authors: Grisel Corro, Surinam Cebada, U Pal, J L G FierroAbstract:Abstract Hydrogen-reduced air-calcined 1%Au/ZnO composite synthesized by gold impregnation in ZnO has been utilized as catalyst for Diesel Particulate Matter (DPM) oxidation. The catalyst was characterized by UV-vis optical absorption, X-ray photoelectron spectroscopy and transmission electronic microscopy. The composite catalyst showed excellent activity for the oxidation of DPM at temperature as low as 230 °C. The activity of the catalyst does not change up to 6 oxidation cycles. The high catalytic activity of the composite has been attributed to the formation of stable Au 0 –Au 3+ bifunctional catalytic sites at the gold-ZnO interface, which enhances the contact efficiency of solid Particulate Matter on Au 3+ and the generation of superoxide species on Au 0 . The high stability of the bifunctional Au 0 -Au 3+ sites is associated with the electronic interactions between gold and n-type semiconductor ZnO at their interface.
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Au0–Au3+ bifunctional site mediated enhanced catalytic activity of Au/ZnO composite in Diesel Particulate Matter oxidation
Journal of Catalysis, 2017Co-Authors: Grisel Corro, Surinam Cebada, Umapada Pal, J L G FierroAbstract:Abstract Hydrogen-reduced air-calcined 1%Au/ZnO composite synthesized by gold impregnation in ZnO has been utilized as catalyst for Diesel Particulate Matter (DPM) oxidation. The catalyst was characterized by UV-vis optical absorption, X-ray photoelectron spectroscopy and transmission electronic microscopy. The composite catalyst showed excellent activity for the oxidation of DPM at temperature as low as 230 °C. The activity of the catalyst does not change up to 6 oxidation cycles. The high catalytic activity of the composite has been attributed to the formation of stable Au 0 –Au 3+ bifunctional catalytic sites at the gold-ZnO interface, which enhances the contact efficiency of solid Particulate Matter on Au 3+ and the generation of superoxide species on Au 0 . The high stability of the bifunctional Au 0 -Au 3+ sites is associated with the electronic interactions between gold and n-type semiconductor ZnO at their interface.
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Low Cost Cu/ZnO as Low Temperature (150 °C) Catalyst for Diesel Particulate Matter Oxidation
Topics in Catalysis, 2016Co-Authors: Grisel Corro, Surinam Cebada, J L G Fierro, Fortino Bañuelos, Umapada Pal, Emmanuel GuilleminotAbstract:The catalytic behavior of hydrogen-reduced copper loaded ZnO, SiO2, and TiO2 has been investigated for Diesel Particulate Matter(PM) oxidation. 5 %Cu/ZnO showed a strong Diesel PM oxidation activity at 150 °C. XPS spectroscopy was utilized to study the electronic states of Cu in Cu/ZnO catalyst. Presence of Cu1+ ions at the surface of the catalyst even after its use in PM oxidation cycles was assigned responsible for its high catalytic performance. The high stability of Cu1+ is explained on basis of the isoelectronic interactions of Cu1+ (3d10) with Zn2+ (3d10) at the Cu2O–ZnO interface. Cu/SiO2 and Cu/TiO2 were not active for this reaction probably due to the absence of Cu1+ which could not be stabilized by Ti4+ or Si4+. Results indicate that 5 %Cu/ZnO catalyst can be utilized for the abatement of Diesel engine emissions even from the starting point of cold engines.
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hydrogen reduced cu zno composite as efficient reusable catalyst for Diesel Particulate Matter oxidation
Applied Catalysis B-environmental, 2015Co-Authors: Grisel Corro, Surinam Cebada, U Pal, J L G Fierro, Josefina AlvaradoAbstract:Abstract Hydrogen-reduced copper-loaded ZnO (Cu/ZnO) showed a strong Diesel Particulate Matter oxidation activity at temperature as low as 150 °C. Cu/ZnO catalyst with 5% nominal Cu content was tested for the oxidation of Diesel Particulate Matter under air flow between 25 and 800 °C. The high catalytic performance of reduced 5%Cu/ZnO even after its use in Diesel Particulate Matter oxidation has been assigned to the presence of Cu 1+ ions at its surface, determined by Auger electronic spectroscopy. The high stability of Cu 1+ could be assigned to the isoelectronic interaction of Cu 1+ (3d 10 ) with Zn 2+ (3d 10 ) at the Cu 2 O–ZnO interface. Results presented in this work indicate that the composite catalyst can be considered as part of an exhaust catalytic system, for abating Diesel Particulate Matter emission at low temperature.
Surinam Cebada - One of the best experts on this subject based on the ideXlab platform.
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au0 au3 bifunctional site mediated enhanced catalytic activity of au zno composite in Diesel Particulate Matter oxidation
Journal of Catalysis, 2017Co-Authors: Grisel Corro, Surinam Cebada, U Pal, J L G FierroAbstract:Abstract Hydrogen-reduced air-calcined 1%Au/ZnO composite synthesized by gold impregnation in ZnO has been utilized as catalyst for Diesel Particulate Matter (DPM) oxidation. The catalyst was characterized by UV-vis optical absorption, X-ray photoelectron spectroscopy and transmission electronic microscopy. The composite catalyst showed excellent activity for the oxidation of DPM at temperature as low as 230 °C. The activity of the catalyst does not change up to 6 oxidation cycles. The high catalytic activity of the composite has been attributed to the formation of stable Au 0 –Au 3+ bifunctional catalytic sites at the gold-ZnO interface, which enhances the contact efficiency of solid Particulate Matter on Au 3+ and the generation of superoxide species on Au 0 . The high stability of the bifunctional Au 0 -Au 3+ sites is associated with the electronic interactions between gold and n-type semiconductor ZnO at their interface.
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Au0–Au3+ bifunctional site mediated enhanced catalytic activity of Au/ZnO composite in Diesel Particulate Matter oxidation
Journal of Catalysis, 2017Co-Authors: Grisel Corro, Surinam Cebada, Umapada Pal, J L G FierroAbstract:Abstract Hydrogen-reduced air-calcined 1%Au/ZnO composite synthesized by gold impregnation in ZnO has been utilized as catalyst for Diesel Particulate Matter (DPM) oxidation. The catalyst was characterized by UV-vis optical absorption, X-ray photoelectron spectroscopy and transmission electronic microscopy. The composite catalyst showed excellent activity for the oxidation of DPM at temperature as low as 230 °C. The activity of the catalyst does not change up to 6 oxidation cycles. The high catalytic activity of the composite has been attributed to the formation of stable Au 0 –Au 3+ bifunctional catalytic sites at the gold-ZnO interface, which enhances the contact efficiency of solid Particulate Matter on Au 3+ and the generation of superoxide species on Au 0 . The high stability of the bifunctional Au 0 -Au 3+ sites is associated with the electronic interactions between gold and n-type semiconductor ZnO at their interface.
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Low Cost Cu/ZnO as Low Temperature (150 °C) Catalyst for Diesel Particulate Matter Oxidation
Topics in Catalysis, 2016Co-Authors: Grisel Corro, Surinam Cebada, J L G Fierro, Fortino Bañuelos, Umapada Pal, Emmanuel GuilleminotAbstract:The catalytic behavior of hydrogen-reduced copper loaded ZnO, SiO2, and TiO2 has been investigated for Diesel Particulate Matter(PM) oxidation. 5 %Cu/ZnO showed a strong Diesel PM oxidation activity at 150 °C. XPS spectroscopy was utilized to study the electronic states of Cu in Cu/ZnO catalyst. Presence of Cu1+ ions at the surface of the catalyst even after its use in PM oxidation cycles was assigned responsible for its high catalytic performance. The high stability of Cu1+ is explained on basis of the isoelectronic interactions of Cu1+ (3d10) with Zn2+ (3d10) at the Cu2O–ZnO interface. Cu/SiO2 and Cu/TiO2 were not active for this reaction probably due to the absence of Cu1+ which could not be stabilized by Ti4+ or Si4+. Results indicate that 5 %Cu/ZnO catalyst can be utilized for the abatement of Diesel engine emissions even from the starting point of cold engines.
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hydrogen reduced cu zno composite as efficient reusable catalyst for Diesel Particulate Matter oxidation
Applied Catalysis B-environmental, 2015Co-Authors: Grisel Corro, Surinam Cebada, U Pal, J L G Fierro, Josefina AlvaradoAbstract:Abstract Hydrogen-reduced copper-loaded ZnO (Cu/ZnO) showed a strong Diesel Particulate Matter oxidation activity at temperature as low as 150 °C. Cu/ZnO catalyst with 5% nominal Cu content was tested for the oxidation of Diesel Particulate Matter under air flow between 25 and 800 °C. The high catalytic performance of reduced 5%Cu/ZnO even after its use in Diesel Particulate Matter oxidation has been assigned to the presence of Cu 1+ ions at its surface, determined by Auger electronic spectroscopy. The high stability of Cu 1+ could be assigned to the isoelectronic interaction of Cu 1+ (3d 10 ) with Zn 2+ (3d 10 ) at the Cu 2 O–ZnO interface. Results presented in this work indicate that the composite catalyst can be considered as part of an exhaust catalytic system, for abating Diesel Particulate Matter emission at low temperature.
M. Eileen Birch - One of the best experts on this subject based on the ideXlab platform.
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Effects of sampling artifacts on occupational samples of Diesel Particulate Matter.
Environmental science & technology, 2008Co-Authors: J.d. Noll, M. Eileen BirchAbstract:Total carbon (TC) is sometimes used to measure or characterize Diesel Particulate Matter (DPM) in occupational settings such as underground mines. DPM samples are collected on quartz fiber filters....
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Submicrometer elemental carbon as a selective measure of Diesel Particulate Matter in coal mines
Journal of Environmental Monitoring, 2004Co-Authors: M. Eileen Birch, J.d. NollAbstract:A monitoring method for Diesel Particulate Matter was published as Method 5040 by the National Institute for Occupational Safety and Health (NIOSH). Organic and elemental carbon are determined by the method, but elemental carbon (EC) is a better exposure measure. The US Mine Safety and Health Administration (MSHA) proposed use of NIOSH 5040 for compliance determinations in metal and nonmetal mines. MSHA also published a rulemaking for coal mines, but no exposure standard was provided. A standard based on Particulate carbon is not considered practical because of coal dust interference. Interference may not be a problem if an appropriate size-selective sampler and EC exposure standard are employed. Submicrometer dust concentrations found in previous surveys of nonDieselized, underground coal mines were relatively low. If a large fraction of the submicrometer dust is organic and mineral Matter, submicrometer EC concentrations would be much lower than submicrometer mass concentrations. Laboratory and field results reported herein indicate the amount of EC contributed by submicrometer coal dust is minor. In a laboratory test, a submicrometer EC concentration of 31 µg m−3 was found when sampling a respirable coal dust concentration over three times the US compliance limit (2 mg m−3). Laboratory results are consistent with surveys of nonDieselized coal mines, where EC results ranged from below the method limit of detection to 18 µg m−3 when size-selective samplers were used to collect dust fractions having particle diameters below 1.5 µm—submicrometer EC concentrations were ≈7 µg m−3. In Dieselized mines, submicrometer EC concentrations are much higher.
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Submicrometer elemental carbon as a selective measure of Diesel Particulate Matter in coal mines
Journal of Environmental Monitoring, 2004Co-Authors: M. Eileen Birch, J.d. NollAbstract:A monitoring method for Diesel Particulate Matter was published as Method 5040 by the National Institute for Occupational Safety and Health (NIOSH). Organic and elemental carbon are determined by the method, but elemental carbon (EC) is a better exposure measure. The US Mine Safety and Health Administration (MSHA) proposed use of NIOSH 5040 for compliance determinations in metal and nonmetal mines. MSHA also published a rulemaking for coal mines, but no exposure standard was provided. A standard based on Particulate carbon is not considered practical because of coal dust interference. Interference may not be a problem if an appropriate size-selective sampler and EC exposure standard are employed. Submicrometer dust concentrations found in previous surveys of nonDieselized, underground coal mines were relatively low. If a large fraction of the submicrometer dust is organic and mineral Matter, submicrometer EC concentrations would be much lower than submicrometer mass concentrations. Laboratory and field results reported herein indicate the amount of EC contributed by submicrometer coal dust is minor. In a laboratory test, a submicrometer EC concentration of 31 µg m−3 was found when sampling a respirable coal dust concentration over three times the US compliance limit (2 mg m−3). Laboratory results are consistent with surveys of nonDieselized coal mines, where EC results ranged from below the method limit of detection to 18 µg m−3 when size-selective samplers were used to collect dust fractions having particle diameters below 1.5 µm—submicrometer EC concentrations were ≈7 µg m−3. In Dieselized mines, submicrometer EC concentrations are much higher.