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Chen Z, Wang C, Pignatello JJ. Rapid and Convenient Potentiometric Method for Determining Fluorosulfate, a Byproduct of the Fumigant and Greenhouse Gas Sulfuryl Fluoride. ACS OMEGA 2024; 9:23013-23020. [PMID: 38826532 PMCID: PMC11137687 DOI: 10.1021/acsomega.4c02629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 04/29/2024] [Accepted: 05/10/2024] [Indexed: 06/04/2024]
Abstract
A fluorosulfate ion (FSO3-) is a hydrolysis product of sulfuryl fluoride (SO2F2), which is widely used to fumigate buildings, soil, construction materials, and postharvest commodities, and is a potent greenhouse gas. It is a potential marker for biological exposure to SO2F2 and for monitoring the progress of reactions used to scrub SO2F2 from fumigation vent gases. Here, we report a simple and inexpensive potentiometric method for determining FSO3- using a commercial nitrate-selective electrode and discuss its application. The method is suitable for solutions between 0.0025 mM and 660 mM FSO3- at initial pH between 5 and 9. Halide interference depends on its molar ratio to FSO3- and follows the sequence, F- < Cl- < Br- ≪ I-. Halide interference can be eliminated by adding silver sulfate. Interference by bicarbonate can be eliminated by H2SO4 pretreatment, and interference by phosphate or pyrophosphate by MgSO4 addition. Sulfate does not interfere, as it does in ion chromatography. Satisfactory method detection limits for FSO3- in spiked aqueous extracts of 11 fruits were obtained. The method accurately quantified the yield of FSO3- relative to that of F- in base hydrolysis of SO2F2. This study demonstrates that the developed method is highly selective, convenient, and sensitive and thus can be of great value in practice.
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Affiliation(s)
- Zhihao Chen
- The
Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511, United States
- School
of Environmental Science and Engineering, East Campus of Sun Yat-sen University, 132 Outer Ring East Road, University Town, Panyu
District, Guangzhou 510330, China
| | - Chengjin Wang
- The
Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511, United States
- Department
of Civil Engineering, University of Manitoba, 15 Gillson St, Winnipeg, Manitoba R3T
5 V6, Canada
| | - Joseph J Pignatello
- The
Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511, United States
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Poulos NA, Lee CY, Rust MK, Choe DH. Potential use of pinenes to improve localized insecticide injections targeting the western drywood termite (Blattodea: Kalotermitidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2024:toae101. [PMID: 38753642 DOI: 10.1093/jee/toae101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/23/2024] [Accepted: 05/03/2024] [Indexed: 05/18/2024]
Abstract
The western drywood termite, Incisitermes minor (Hagen), causes significant economic damage to wood structures in the United States of America, especially California. When infestation is not widespread, localized insecticide injections may be useful for remedial control. However, the extensive gallery structure of drywood termites and their tendency to aggregate at specific parts of the galleries can impact the efficacy of localized insecticide injection. Chemicals that attract termites from a distance may improve the localized insecticide injection by increasing the number of termites contacting the insecticide residues. Two volatile terpenes, α-pinene and β-pinene, commonly found in many coniferous timber trees, were applied to artificial termite galleries to determine if termites were attracted from their original aggregation site. Furthermore, we examined if adding these pinenes would improve the overall efficacy of some insecticide products for drywood termite control. Behavioral assay results showed that the treatment with pinenes increased the likelihood that drywood termites would leave their original aggregation site and contact the treated part of the gallery. When tested with the pesticide products applied in a small area away from the termite aggregation, β-pinene significantly accelerated the time course of mortality for the aqueous fipronil. The efficacy of disodium octaborate tetrahydrate dust was not influenced by the addition of pinenes. Implications for drywood termite management and future research directions are discussed.
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Affiliation(s)
- Nicholas A Poulos
- Department of Entomology, University of California, 900 University Avenue, Riverside, CA 92521, USA
| | - Chow-Yang Lee
- Department of Entomology, University of California, 900 University Avenue, Riverside, CA 92521, USA
| | - Michael K Rust
- Department of Entomology, University of California, 900 University Avenue, Riverside, CA 92521, USA
| | - Dong-Hwan Choe
- Department of Entomology, University of California, 900 University Avenue, Riverside, CA 92521, USA
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Yassine H, Weber C, Brugger N, Wöllenstein J, Schmitt K. Towards a Miniaturized Photoacoustic Detector for the Infrared Spectroscopic Analysis of SO 2F 2 and Refrigerants. SENSORS (BASEL, SWITZERLAND) 2022; 23:180. [PMID: 36616778 PMCID: PMC9824166 DOI: 10.3390/s23010180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/16/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
Sulfuryl fluoride (SO2F2) is a toxic and potent greenhouse gas that is currently widely used as a fumigant insecticide in houses, food, and shipping containers. Though it poses a major hazard to humans, its detection is still carried out manually and only on a random basis. In this paper, we present a two-chamber photoacoustic approach for continuous SO2F2 sensing. Because of the high toxicity of SO2F2, the concept is to use a non-toxic substituent gas with similar absorption characteristics in the photoacoustic detector chamber, i.e., to measure SO2F2 indirectly. The refrigerants R227ea, R125, R134a, and propene were identified as possible substituents using a Fourier-transform infrared (FTIR) spectroscopic analysis. The resulting infrared spectra were used to simulate the sensitivity of the substituents of a photoacoustic sensor to SO2F2 in different concentration ranges and at different optical path lengths. The simulations showed that R227ea has the highest sensitivity to SO2F2 among the substituents and is therefore a promising substituent detector gas. Simulations concerning the possible cross-sensitivity of the photoacoustic detectors to H2O and CO2 were also performed. These results are the first step towards the development of a miniaturized, sensitive, and cost-effective photoacoustic sensor system for SO2F2.
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Affiliation(s)
- Hassan Yassine
- Department of Microsystems Engineering, University of Freiburg, 79110 Freiburg, Germany
| | - Christian Weber
- Department of Microsystems Engineering, University of Freiburg, 79110 Freiburg, Germany
- Fraunhofer Institute for Physical Measurement Techniques IPM, 79110 Freiburg, Germany
| | - Nicolas Brugger
- Department of Microsystems Engineering, University of Freiburg, 79110 Freiburg, Germany
| | - Jürgen Wöllenstein
- Department of Microsystems Engineering, University of Freiburg, 79110 Freiburg, Germany
- Fraunhofer Institute for Physical Measurement Techniques IPM, 79110 Freiburg, Germany
| | - Katrin Schmitt
- Department of Microsystems Engineering, University of Freiburg, 79110 Freiburg, Germany
- Fraunhofer Institute for Physical Measurement Techniques IPM, 79110 Freiburg, Germany
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Wang Y, Gao Z, Wang B, Zhou W, Yu P, Luo Y. Synthesis and Dielectric Properties of Trifluoromethanesulfonyl Fluoride: An Alternative Gas to SF 6. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b05633] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yi Wang
- Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Zhanyang Gao
- Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Baoshan Wang
- Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Wenjun Zhou
- School of Electrical Engineering and Automation, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Ping Yu
- Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People’s Republic of China
| | - Yunbai Luo
- Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People’s Republic of China
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Sulfuryl Fluoride Poisonings in Structural Fumigation, a Highly Regulated Industry-Potential Causes and Solutions. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16112026. [PMID: 31174396 PMCID: PMC6603922 DOI: 10.3390/ijerph16112026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 05/23/2019] [Accepted: 05/29/2019] [Indexed: 11/29/2022]
Abstract
Structural fumigations using sulfuryl fluoride for the extermination of dry-wood termites are conducted by the thousands in California and other warm-weather states. Sulfuryl fluoride is an odorless gas that targets the nervous system and can cause respiratory irritation, pulmonary edema, nausea, vomiting, seizures, and death. Structural voids or compartments such as wall sockets, crawl spaces, cabinets, or cells in air mattresses may create ongoing exposure after a structure has been certified as safe. The authors describe a case of potential sulfuryl fluoride exposure to a family following home fumigation. Despite regulation, sulfuryl fluoride poisonings from structural fumigations continue to occur. This article examines the physical characteristics of sulfuryl fluoride and the regulatory oversight of its application, in an effort to understand how and why these poisonings happen. Increasing aeration times of fumigated structures, overseeing monitoring efficacy, and using technology to capture clearance data could reduce sulfuryl fluoride exposure and illness.
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Liang X, Fei Y, Xie Q, Liu Y, Lu M, Xia F, Nie Y, Ji J. Sulfuryl Fluoride Absorption from Fumigation Exhaust Gas by Biobased Solvents: Thermodynamic and Quantum Chemical Analysis. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.8b06112] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xiaojiang Liang
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yanren Fei
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Qinglong Xie
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yang Liu
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Meizhen Lu
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Fan Xia
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yong Nie
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jianbing Ji
- Zhejiang Province Key Laboratory of Biofuel, Biodiesel Laboratory of China Petroleum and Chemical Industry Federation, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China
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Yu X, Hou H, Wang B. A Priori Theoretical Model for Discovery of Environmentally Sustainable Perfluorinated Compounds. J Phys Chem A 2018; 122:3462-3469. [PMID: 29561611 DOI: 10.1021/acs.jpca.8b00606] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Since SF6 is the most potent greenhouse gas, the search for a viable alternative is taking on great urgency for several decades but without success. The demanding combination of performance, safety, and environmental properties for the new chemistry superior to SF6 was thought to be nearly impossible to achieve. In contrast to the commonly used mixtures with two or three individual gases, a hybrid model has been proposed to create the new perfluorinated compounds with multiple unsaturated chemical bonds by means of full or partial integration of the parent molecules. A unique combination of a series of paradoxical properties that is high in dielectric strength and stability, low in boiling point, and significantly lower in global warming potential is achieved for the first time. The present a priori theoretical predictions shed new lights on the rational molecular design of the perfluorinated compounds and will greatly inspire experimental synthesis and field tests on the new chemistry for dielectric use.
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Affiliation(s)
- Xiaojuan Yu
- College of Chemistry and Molecular Sciences , Wuhan University , Wuhan , 430072 , People's Republic of China
| | - Hua Hou
- College of Chemistry and Molecular Sciences , Wuhan University , Wuhan , 430072 , People's Republic of China
| | - Baoshan Wang
- College of Chemistry and Molecular Sciences , Wuhan University , Wuhan , 430072 , People's Republic of China
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Sulbaek Andersen MP, Kyte M, Andersen ST, Nielsen CJ, Nielsen OJ. Atmospheric Chemistry of (CF 3) 2CF-C≡N: A Replacement Compound for the Most Potent Industrial Greenhouse Gas, SF 6. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:1321-1329. [PMID: 27936633 DOI: 10.1021/acs.est.6b03758] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
FTIR/smog chamber experiments and ab initio quantum calculations were performed to investigate the atmospheric chemistry of (CF3)2CFCN, a proposed replacement compound for the industrially important sulfur hexafluoride, SF6. The present study determined k(Cl + (CF3)2CFCN) = (2.33 ± 0.87) × 10-17, k(OH + (CF3)2CFCN) = (1.45 ± 0.25) × 10-15, and k(O3 + (CF3)2CFCN) ≤ 6 × 10-24 cm3 molecule-1 s-1, respectively, in 700 Torr of N2 or air diluent at 296 ± 2 K. The main atmospheric sink for (CF3)2CFCN was determined to be reaction with OH radicals. Quantum chemistry calculations, supported by experimental evidence, shows that the (CF3)2CFCN + OH reaction proceeds via OH addition to -C(≡N), followed by O2 addition to -C(OH)═N·, internal H-shift, and OH regeneration. The sole atmospheric degradation products of (CF3)2CFCN appear to be NO, COF2, and CF3C(O)F. The atmospheric lifetime of (CF3)2CFCN is approximately 22 years. The integrated cross section (650-1500 cm-1) for (CF3)2CFCN is (2.22 ± 0.11) × 10-16 cm2 molecule-1 cm-1 which results in a radiative efficiency of 0.217 W m-2 ppb-1. The 100-year Global Warming Potential (GWP) for (CF3)2CFCN was calculated as 1490, a factor of 15 less than that of SF6.
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Affiliation(s)
- Mads P Sulbaek Andersen
- Department of Chemistry and Biochemistry, California State University , Northridge, California 91330, United States
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen , 2100 Copenhagen Ø, Denmark
| | - Mildrid Kyte
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen , 2100 Copenhagen Ø, Denmark
| | - Simone Thirstrup Andersen
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen , 2100 Copenhagen Ø, Denmark
| | - Claus J Nielsen
- Department of Chemistry, University of Oslo , P.O. Box 1033, Blindern, 0315 Oslo, Norway
| | - Ole John Nielsen
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen , 2100 Copenhagen Ø, Denmark
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Gallagher G, Zhan T, Hsu YK, Gupta P, Pederson J, Croes B, Blake DR, Barletta B, Meinardi S, Ashford P, Vetter A, Saba S, Slim R, Palandre L, Clodic D, Mathis P, Wagner M, Forgie J, Dwyer H, Wolf K. High-global warming potential F-gas emissions in California: comparison of ambient-based versus inventory-based emission estimates, and implications of refined estimates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:1084-1093. [PMID: 24328112 DOI: 10.1021/es403447v] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To provide information for greenhouse gas reduction policies, the California Air Resources Board (CARB) inventories annual emissions of high-global-warming potential (GWP) fluorinated gases, the fastest growing sector of greenhouse gas (GHG) emissions globally. Baseline 2008 F-gas emissions estimates for selected chlorofluorocarbons (CFC-12), hydrochlorofluorocarbons (HCFC-22), and hydrofluorocarbons (HFC-134a) made with an inventory-based methodology were compared to emissions estimates made by ambient-based measurements. Significant discrepancies were found, with the inventory-based emissions methodology resulting in a systematic 42% under-estimation of CFC-12 emissions from older refrigeration equipment and older vehicles, and a systematic 114% overestimation of emissions for HFC-134a, a refrigerant substitute for phased-out CFCs. Initial, inventory-based estimates for all F-gas emissions had assumed that equipment is no longer in service once it reaches its average lifetime of use. Revised emission estimates using improved models for equipment age at end-of-life, inventories, and leak rates specific to California resulted in F-gas emissions estimates in closer agreement to ambient-based measurements. The discrepancies between inventory-based estimates and ambient-based measurements were reduced from -42% to -6% for CFC-12, and from +114% to +9% for HFC-134a.
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Affiliation(s)
- Glenn Gallagher
- California Air Resources Board, 1001 I Street, Sacramento, California 95814, United States
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Weiss RF, Prinn RG. Quantifying greenhouse-gas emissions from atmospheric measurements: a critical reality check for climate legislation. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2011; 369:1925-1942. [PMID: 21502167 DOI: 10.1098/rsta.2011.0006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Emissions reduction legislation relies upon 'bottom-up' accounting of industrial and biogenic greenhouse-gas (GHG) emissions at their sources. Yet, even for relatively well-constrained industrial GHGs, global emissions based on 'top-down' methods that use atmospheric measurements often agree poorly with the reported bottom-up emissions. For emissions reduction legislation to be effective, it is essential that these discrepancies be resolved. Because emissions are regulated nationally or regionally, not globally, top-down estimates must also be determined at these scales. High-frequency atmospheric GHG measurements at well-chosen station locations record 'pollution events' above the background values that result from regional emissions. By combining such measurements with inverse methods and atmospheric transport and chemistry models, it is possible to map and quantify regional emissions. Even with the sparse current network of measurement stations and current inverse-modelling techniques, it is possible to rival the accuracies of regional 'bottom-up' emission estimates for some GHGs. But meeting the verification goals of emissions reduction legislation will require major increases in the density and types of atmospheric observations, as well as expanded inverse-modelling capabilities. The cost of this effort would be minor when compared with current investments in carbon-equivalent trading, and would reduce the volatility of that market and increase investment in emissions reduction.
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Affiliation(s)
- Ray F Weiss
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0244, USA.
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11
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Rigby M, Ganesan AL, Prinn RG. Deriving emissions time series from sparse atmospheric mole fractions. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd015401] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tang X, Wilson SR, Solomon KR, Shao M, Madronich S. Changes in air quality and tropospheric composition due to depletion of stratospheric ozone and interactions with climate. Photochem Photobiol Sci 2011; 10:280-91. [DOI: 10.1039/c0pp90039g] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Miller TM, Friedman JF, Caples CM, Shuman NS, Van Doren JM, Bardaro MF, Nguyen P, Zweiben C, Campbell MJ, Viggiano AA. Electron attachment to sulfur oxyhalides: SOF2, SOCl2, SO2F2, SO2Cl2, and SO2FCl attachment rate coefficients, 300–900 K. J Chem Phys 2010; 132:214302. [DOI: 10.1063/1.3427527] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Johnson JA. Effect of relative humidity and product moisture on response of diapausing and nondiapausing Indianmeal moth (Lepidoptera: Pyralidae) larvae to low pressure treatments. JOURNAL OF ECONOMIC ENTOMOLOGY 2010; 103:612-618. [PMID: 20568605 DOI: 10.1603/ec09334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Low pressure treatment in flexible polyvinyl chloride containers is a potential alternative to chemical fumigants for California tree nuts. Laboratory studies investigated the effect of relative humidity and product moisture on weight loss and mortality of diapausing and nondiapausing larvae of the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), exposed to 50 mmHg. Diapausing larvae were far more tolerant than nondiapausing larvae to low pressure; exposure times nearly twice those of nondiapausing larvae were required to obtain comparable weight loss or mortality levels in diapausing larvae. Relative humidity was found to have a large effect on both weight loss (assumed to be due to moisture loss) and mortality of both nondiapausing and diapausing larvae. Mortality and weight loss increased as humidity levels decreased. By controlling the relative humidity of the treatment chamber, product moisture also strongly affected weight loss and mortality. The results suggest that for tree nuts, product moisture levels may affect the efficacy of low pressure treatments.
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Affiliation(s)
- J A Johnson
- San Joaquin Valley Agricultural Sciences Center, USDA-ARS, 9611 South Riverbend Avenue, Parlier, CA 93648, USA.
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