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3. A Measuring System for PM2.5 Concentration and Meteorological Parameters for a Multipoint Aerosol Monitoring Network in Yekaterinburg.

Author

Vasilyeva, D. E., Gulyaev, E. A., Imasu, R., Markelov, Yu. I., Matsumi, Y., Talovskaya, A. V., Shchelkanov, A. A., and Gadelshin, V. M.

Abstract

The outcome of the first tests of a measuring system designed for the monitoring of atmospheric aerosol and meteorological parameters is considered. Based on the measurement results from August 2022, the data of the system prototypes, a calibrated optical aerosol sensor, and the on-site meteorological station are compared. The revealed drawbacks of the system design are described. The plans to improve and extend the system capabilities are discussed. A blueprint of a future multipoint aerosol monitoring network in Yekaterinburg and its neighborhood is presented. [ABSTRACT FROM AUTHOR]

Published
2023
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4. Seasonal variation of carbon monoxide in northern Japan: Fourier transform IR measurements and source-labeled model calculations

Author

Koike, M, Jones, N B, Palmer, P I, Matsui, H, Zhao, Y, Kondo, Y, Matsumi, Y, and Tanimoto, H

Abstract

[ 1] Tropospheric carbon monoxide ( CO) was measured throughout 2001 using groundbased Fourier transform IR ( FTIR) spectrometers at Moshiri (44.4 degrees N) and Rikubetsu (43.5 degrees N) observatories in northern Japan, which are separated by 150 km. Seasonal and day-to-day variations of CO are studied using these data, and contributions from various CO sources are evaluated using three-dimensional global chemistry transport model (GEOS-CHEM) calculations. Seasonal maximum and minimum FTIR-derived tropospheric CO amounts occurred in April and September, respectively. The ratio of partial column amounts between the 0 - 4 and 0 - 12 km altitude ranges is found to be slightly greater in early spring. The GEOS-CHEM model calculations generally reproduce these observed features. Source-labeled CO model calculations suggest that the observed seasonal variation is caused by seasonal contributions from various sources, in addition to a seasonal change in chemical CO loss by OH. Changes in meteorological fields largely control the relative importance of various source contributions. The contributions from fossil fuel (FF) combustion in Asia and photochemical CO production have the greatest yearly averaged contribution at 1 km among the CO sources (31% each). The Asian FF contribution increases from winter to summer, because weak southwesterly wind in summer brings more Asian pollutants to the observation sites. The seasonal variation from photochemical CO production is small ( +/- 17% at 1 km), likely because of concurrent increases ( decreases) of photochemical production and loss rates in summer ( winter), with the largest contribution between August and December. The contribution from intercontinental transport of European FF combustion CO is found to be comparable to that of Asian FF sources in winter. Northwesterly wind around the Siberian high in this season brings pollutants from Europe directly to Japan, in addition to southward transport of accumulated pollution from higher latitudes. The influences are generally greater at lower altitudes, resulting in a vertical gradient in the CO profile during winter. The model underestimates total CO by 12 - 14% between March and June. Satellite-derived fire-count data and the relationship between FTIR-derived HCN and CO amounts are generally consistent with biomass burning influences, which could have been underestimated by the model calculations.

Published
2006

17. Remotely operable compact instruments for measuring atmospheric CO2 and CH4 column densities at surface monitoring sites

Author

Kobayashi, N., Inoue, G., Kawasaki, M., Yoshioka, H., Minomura, M., Murata, I., Nagahama, T., Matsumi, Y., Tanaka, T., Morino, I., and Ibuki, T.

Subjects
lcsh:TA715-787, lcsh:Earthwork. Foundations, lcsh:TA170-171, lcsh:Environmental engineering
Abstract

Remotely operable compact instruments for measuring atmospheric CO2 and CH4 column densities were developed in two independent systems: one utilizing a grating-based desktop optical spectrum analyzer (OSA) with a resolution enough to resolve rotational lines of CO2 and CH4 in the regions of 1565–1585 and 1674–1682 nm, respectively; the other is an application of an optical fiber Fabry-Perot interferometer (FFPI) to obtain the CO2 column density. Direct sunlight was collimated via a small telescope installed on a portable sun tracker and then transmitted through an optical fiber into the OSA or the FFPI for optical analysis. The near infrared spectra of the OSA were retrieved by a least squares spectral fitting algorithm. The CO2 and CH4 column densities deduced were in excellent agreement with those measured by a Fourier transform spectrometer with high resolution. The rovibronic lines in the wavelength region of 1570–1575 nm were analyzed by the FFPI. The I0 and I values in the Beer-Lambert law equation to obtain CO2 column density were deduced by modulating temperature of the FFPI, which offered column CO2 with the statistical error less than 0.2% for six hours measurement.

Published
2018

21. Kinetics and mechanism of the reaction of chlorine atoms with n-pentanal

Author

Iwasaki, E., Nakayama, T., Matsumi, Y., Takahashi, K., Wallington, T.J., Hurley, M.D., and Kaiser, E.W.

Subjects
Aldehydes -- Structure, Aldehydes -- Mechanical properties, Chlorine compounds -- Structure, Chlorine compounds -- Mechanical properties, Dynamics -- Analysis, Fourier transform infrared spectroscopy -- Analysis, Chemicals, plastics and rubber industries
Abstract

A number of absolute and relative rate techniques in 8 Torr of argon or 800-950 Torr of [N.sub.2] was used to explore the kinetics and mechanisms of the reaction Cl + C[H.sub.3][(C[H.sub.2]).sub.3]CHO. The results emphasize the significance of long range effects in determining the reactivity of organic molecules toward chlorine atoms.

Published
2008

24. Time resolved study of the B 3Σ-u and B‘ 3Πu states of diatomic sulfur in a supersonic free jet.

Author

Matsumi, Y., Suzuki, Takanori, Munakata, Toshiaki, and Kasuya, Takahiro

Subjects
*SULFUR, *JETS (Nuclear physics), *DECAY schemes (Radioactivity), *FLUORESCENCE, *QUANTUM perturbations
Abstract

Fluorescence decay rates were measured for individual rovibronic spin levels of the B 3Σ-u and B‘3Πu states of diatomic sulfur (S2) in a supersonic free jet. The radiative lifetimes of the B 3Σ-u and B‘3Πu states were found to be strongly dependent on the spin and vibrational quantum numbers, and fall in the range of 34.2 to 49.3 and 108 to 3888 ns, respectively. The marked variation of the lifetimes was interpreted satisfactorily in terms of the homogeneous interactions between the B 3Σ-u and B‘3Πu states. A quantitative deperturbation treatment of both the spectroscopic and lifetime data leads to the evaluation of interaction strengths between the B 3Σ-u and B‘ 3Πu states. [ABSTRACT FROM AUTHOR]

Published
1985
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25. Emission spectra of SiH(A 2Δ→X 2Π) and SiCl2(A 1B1→X 1A1) in the VUV photolyses of silane and chlorinated silanes.

Author

Washida, N., Matsumi, Y., Hayashi, T., Ibuki, T., Hiraya, A., and Shobatake, K.

Subjects
*EMISSION spectroscopy, *SILANE compounds, *PHOTOCHEMISTRY, *SYNCHROTRON radiation
Abstract

Vacuum UV photolyses of silane and chlorinated silanes were investigated by using rare gas resonance lamps. Strong emissions, from the A 2Δ→X 2Π transition of SiH and the 1P0→1D2 transition of Si were observed in the photolysis of SiH4 by Ar and Kr resonance lamps. It was suggested that the threshold energies for the appearance of both emissions were lower than the values obtained by the electron impact of SiH4 reported by Perrin et al. A new broad unstructured emission band in the region 300–400 nm was observed in the photolysis of SiH2Cl2 and SiHCl3 by Ar, Kr, and Xe lamps. The band was attributed to the A 1B1→X 1A1 transition of SiCl2 radicals from the measurement of the appearance energy of the emission by using synchrotron orbital radiation. [ABSTRACT FROM AUTHOR]

Published
1985
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26. Above-threshold effects in the photo dissociation and photoionization of iodobenzene

Author

Langchi Zhu, Yan Du, Unny, Sujatha, Gordon, Robert J., Sugita, Akihiro, Matsumi, Y., Kawasaki, Masahiro, Berces, Attila, Parker, David H., and Delmdahl, Ralph

Subjects
Photon beams -- Research, Benzene -- Research, Photoionization -- Research, Chemicals, plastics and rubber industries
Abstract

The method of velocity map imaging is used to investigate the photoinduced dynamics of iodobenzene in weak laser fields as well as in fields of sufficient intensity to produce multiphoton excitation without dressing the potential energy surfaces. Ion and electron images produced with intense visible radiation show both two-photon threshold dissociation and higher order ionization processes.

Published
2001

27. A sensitive study of real time storm surge forecast model to meteorological and hydrodynamic fields along the Sanin coast, Japan

Author

Kim, S.Y., Shiozaki, S., and Matsumi, Y.

Subjects
Storm surge, real time forecast, artificial neural network
Abstract

In the present study, the performance of the real time storm surge forecast model based on the neural network is examined by forecasting Typhoon Megi storm surge 2003 at Sakai, Japan in terms of a variety of the combinations of data obtained from Typhoons Songda 2004 and Maemi 2003. In the experiments, the data sets are trained with the meteorological data measured at five stations: the sea level pressure, the depression rate of the sea level pressure, the wind speed, the wind direction; the hydroulic data: the sea surface level and the storm surge at Sakai; the typhoon parameters: the typhoon position, the central pressure of the typhoon and the highest wind speed near the typhoon center. In addition, the forecast time spans of 01, 02, 03, 04, 05, 12 and 24 hours are investigated for all cases of the data sets. From the results, It is found that the performance of the real time forecast models shows best when training the neural network with the data set of the storm surge, the sea level pressure, the depression rates of the sea level pressure, the wind speed and the typhoon position at Sakai.

Published
2013

28. Modeling of damage progression for rubble mound revetment

Author

Ota, T., Matsumi, Y., Hatono, A., and Satow, T.

Subjects
Damage progression process, markov chain model, maintenance, digestive, oral, and skin physiology
Abstract

Based on the experimental results for profile change of rubble mound revetment, the modeling of damage progression process is discussed in this study. The ranks that indicate the degree of damage for the revetment are determined and the ratio for each rank of damage level is obtained from the experimental data. Three models based on Markov chain model are applied to the transition process of the ratio. The stationary transition probability is obtained for each model and the damage progression is predicted. The model that includes the transition to more than two ranks can predict the transition process of the ratio well.

Published
2013

29. Seasonal and annual variation of AIRS retrieved $$\hbox {CO}_{{2}}$$ CO2 over India during 2003–2011

Author

Gupta, Anju, Dhaka, S, Matsumi, Y, Imasu, R, Hayashida, S, and Singh, Vir

Abstract

The present study shows spatio-temporal variability in carbon dioxide $$(\hbox {CO}_{2})$$ (CO2) in the mid-tropospheric region over India (0–32$$^{\mathrm{o}}\hbox {N}$$ oN , 60–100$$^{\mathrm{o}}\hbox {E}$$ oE ) during 2003–2011. The $$\hbox {CO}_{2}$$ CO2 data used in the study is retrieved from Atmospheric Infra-Red Sounder (AIRS). Analysis of 9 yrs of data shows that the $$\hbox {CO}_{{2}}$$ CO2 exhibits a linear increasing trend of 2.01 ppm/year. Besides displaying the linear increasing trend, data show strong seasonal and annual variability. Concentration of $$\hbox {CO}_{{2}}$$ CO2 is observed to be highest around April–May (summer months), which decreases by 4–5 ppm during the monsoon months. Seasonal decrease in $$\hbox {CO}_{2}$$ CO2 concentration appeared to be influenced by the monsoonal activity. Low OLR (proxy of convection) associated with high rainfall during summer monsoon via increasing vegetation index (NDVI) appears to be the primary cause for the seasonal decrease in $$\hbox {CO}_{{2}}$$ CO2 through photosynthesis. Correlation coefficient between $$\hbox {CO}_{{2}}$$ CO2 and NDVI is of the order of –0.90 suggesting vegetation as a seasonal sink of $$\hbox {CO}_{{2}}$$ CO2 . Decrease in $$\hbox {CO}_{{2}}$$ CO2 concentration takes place at a delay of 2–3 months of rainfall. However, convection seems to be another component, which causes uplifting of $$\hbox {CO}_{{2}}$$ CO2 during dry summer (April and May) making high concentration in the mid-troposphere as shown by increase in the planetary boundary layer (PBL) height in this period. Eastward propagating intra-seasonal oscillations with period 30–40 days in OLR anomalies are found to modulate (with a fluctuation of 1–2 ppm) mid-tropospheric $$\hbox {CO}_{{2}}$$ CO2 . Analysis of seasonal anomalies in $$\hbox {CO}_{{2}}$$ CO2 over four different regions (northern, southern, western and eastern) of India is also being investigated. The regional variability of $$\hbox {CO}_{2}$$ CO2 in northern region show marginal larger values suggesting more anthropogenic activities especially during late winter.

Published
2019
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34. Atmospheric deuterium fractionation: HCHO and HCDO yields in the CH2DO + O2 reaction

Author

Nilsson, E. J. K., Johnson, M. S., Taketani, F., Matsumi, Y., Hurley, M. D., Wallington, T. J., Copenhagen Chemistry Atmospheric Research (CCAR), University of Copenhagen = Københavns Universitet (KU), Solar-Terrestrial Environment Laboratory [Nagoya] (STEL), Nagoya University, and Research and Innovation Center

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere
Abstract

International audience; The formation of formaldehyde via hydrogen atom transfer from the methoxy radical to molecular oxygen is a key step in the atmospheric photochemical oxidation of methane, and in the propagation of deuterium from methane to molecular hydrogen. We report the results of the first investigation of the branching ratio for HCHO and HCDO formation in the CH2DO + O2 reaction. Labeled methoxy radicals (CH2DO) were generated in a photochemical reactor by photolysis of CH2DONO. HCHO and HCDO concentrations were measured using FTIR spectroscopy. Significant deuterium enrichment was seen in the formaldehyde product, from which we derive a branching ratio of 88.2±1.1% for HCDO and 11.8±1.1% for HCHO. The implications of this fractionation on the propagation of deuterium in the atmosphere are discussed.

Published
2007

39. Atmospheric chemistry of cyclohexanone: UV spectrum and kinetics of reaction with chlorine atoms

Author

Department of Natural Sciences, 4901 Evergreen Road, University of Michigan–Dearborn, Dearborn, MI 48128, Solar-Terrestrial Environment Laboratory and Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan, Kyoto University Pioneering Research Unit for Next Generation, Kyoto University Gokasho, Uji, Kyoto 611-0011, Japan, Ford Motor Company, Mail Drop RIC-2122, P.O. Box 2053, Dearborn, MI 48121-2053 ; Ford Motor Company, Mail Drop RIC-2122, P.O. Box 2053, Dearborn, MI 48121-2053, Ford Motor Company, Mail Drop RIC-2122, P.O. Box 2053, Dearborn, MI 48121-2053, Atmospheric Chemistry Division, Earth and Sun Systems Laboratory, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-3000, Environmental Sciences Division, Oak Ridge National Laboratory, Building 1505, Room 368, Oak Ridge, TN 37831-6036, Iwasaki, E., Matsumi, Y., Takahashi, K., Wallington, T. J., Hurley, M. D., Orlando, J. J., Kaiser, E. W., Calvert, J. G., Department of Natural Sciences, 4901 Evergreen Road, University of Michigan–Dearborn, Dearborn, MI 48128, Solar-Terrestrial Environment Laboratory and Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan, Kyoto University Pioneering Research Unit for Next Generation, Kyoto University Gokasho, Uji, Kyoto 611-0011, Japan, Ford Motor Company, Mail Drop RIC-2122, P.O. Box 2053, Dearborn, MI 48121-2053 ; Ford Motor Company, Mail Drop RIC-2122, P.O. Box 2053, Dearborn, MI 48121-2053, Ford Motor Company, Mail Drop RIC-2122, P.O. Box 2053, Dearborn, MI 48121-2053, Atmospheric Chemistry Division, Earth and Sun Systems Laboratory, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-3000, Environmental Sciences Division, Oak Ridge National Laboratory, Building 1505, Room 368, Oak Ridge, TN 37831-6036, Iwasaki, E., Matsumi, Y., Takahashi, K., Wallington, T. J., Hurley, M. D., Orlando, J. J., Kaiser, E. W., and Calvert, J. G.

Abstract

Absolute and relative rate techniques were used to study the reactivity of Cl atoms with cyclohexanone in 6 Torr of argon or 800–950 Torr of N 2 at 295 ± 2 K. The absolute rate experiments gave k (Cl + cyclohexanone) = (1.88 ± 0.38) × 10 −10 , whereas the relative rate experiments gave k (Cl + cyclohexanone) = (1.66 ± 0.26) × 10 −10 cm 3 molecule −1 s −1 . Cyclohexanone has a broad UV absorption band with a maximum cross section of (4.0 ± 0.3) × 10 −20 cm 2 molecule −1 near 285 nm. The results are discussed with respect to the literature data. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 223–229, 2008

Published
2008

42. Atmospheric chemistry of CF3CH‗CH2 and C4F9CH‗CH2:products of the gas-phase reactions with Cl atoms and OH radicals

Author

Nakayama, T., Takahashi, K., Matsumi, Y., Toft, A., Andersen, Mads Peter Sulbæk, Nielsen, Ole John, Waterland, R. L., Buck, R. C., Hurley, M. D., Wallington, T. J., Nakayama, T., Takahashi, K., Matsumi, Y., Toft, A., Andersen, Mads Peter Sulbæk, Nielsen, Ole John, Waterland, R. L., Buck, R. C., Hurley, M. D., and Wallington, T. J.

Abstract

FTIR-smog chamber techniques were used to study the products of the Cl atom and OH radical initiated oxidation of CF3CHCH2 in 700 Torr of N-2/O-2, diluent at 296 K. The Cl atom initiated oxidation of CF3CHCH2 in 700 Torr of air in the absence of NOx gives CF3C(O)CH2Cl and CF3CHO in yields of 70 +/- 5% and 6.2 +/- 0.5 respectively. Reaction with Cl atoms proceeds via addition to the > CC CC

Published
2007

43. Kinetic study of the collisional quenching of spin-orbitally excited atomic chlorine, Cl( 2 P 1/2 ), by H 2 O D 2 O, and H 2 O 2

Author

Kono, Mitsuhiko, Takahashi, K, Matsumi, Y, Kono, Mitsuhiko, Takahashi, K, and Matsumi, Y

Abstract

Rate constants for the collisional quenching of spin-orbitally excited Cl(2P1/2) atoms by H2O, D2O, and H2O2 were determined at ∼295 K using laser-flash photolysis and laser-induced fluorescence techniques in the vacuum ultraviolet energy region. The ra

Published
2006

44. Seasonal variation of carbon monoxide in northern Japan: Fourier transform IR measurements and source-labeled model calculations

Author

Jones, Nicholas B, Zhao, Y, Matsumi, Y, Palmer, Paul, Matsui, H, Koike, Makoto, Tanimoto, H, Kondo, Y, Jones, Nicholas B, Zhao, Y, Matsumi, Y, Palmer, Paul, Matsui, H, Koike, Makoto, Tanimoto, H, and Kondo, Y

Abstract

Tropospheric carbon monoxide (CO) was measured throughout 2001 using groundbased Fourier transform IR (FTIR) spectrometers at Moshiri 44.4N and Rikubetsu 43.5N) observatories in northern Japan, which are separated by 150 km. Seasonal and day-to-day variations of CO are studied using these data, and contributions from various CO sources are evaluated using three-dimensional global chemistry transport model (GEOS-CHEM) calculations. Seasonal maximum and minimum FTIR-derived tropospheric CO amounts occurred in April and September, respectively. The ratio of partial column amounts between the 0–4 and 0–12 km altitude ranges is found to be slightly greater in early spring. The GEOS-CHEM model calculations generally reproduce these observed features. Source-labeled CO model calculations suggest that the observed seasonal variation is caused by seasonal contributions from various sources, in addition to a seasonal change in chemical CO loss by OH. Changes in meteorological fields largely control the relative importance of various source contributions. The contributions from fossil fuel (FF) combustion in Asia and photochemical CO production have the greatest yearly averaged contribution at 1 km among the CO sources (31% each). The Asian FF contribution increases from winter to summer, because weak southwesterly wind in summer brings more Asian pollutants to the observation sites. The seasonal variation from photochemical CO production is small (±17% at 1 km), likely because of concurrent increases (decreases) of photochemical production and loss rates in summer (winter), with the largest contribution between August and December. The contribution from intercontinental transport of European FF combustion CO is found to be comparable to that of Asian FF sources in winter. Northwesterly wind around the Siberian high in this season brings pollutants from Europe directly to Japan, in addition to southward transport of accumulated pollution from higher latitudes. The influences a

Published
2006

46. A kinetics and mechanistic study of the OH and NO2 initiated oxidation of cyclohexa-1,3-diene in the gas phase

Author

Jenkin, M. E., Andersen, Mads Peter Sulbæk, Hurley, M. D., Wallington, T. J., Taketani, F., Matsumi, Y., Jenkin, M. E., Andersen, Mads Peter Sulbæk, Hurley, M. D., Wallington, T. J., Taketani, F., and Matsumi, Y.

Abstract

The kinetics and products of the OH and NO2-initiated oxidation of cyclohexa-1,3-diene have been investigated at 296 K and 700 Torr using long path FTIR spectroscopy. Relative rate methods were employed using the photolysis of cyclohexa-1,3-diene/CH3ONO/NO/air mixtures to measure k(OH + cyclohexa-1,3-diene) = (1.68 +/- 0.43) x 10(-10) cm(3) molecule(-1) s(-1). From the pseudo-first order decay of cyclohexa-1,3-diene in the presence of excess NO2, a value of k(NO2 + cyclohexa- 1,3- diene) = (1.75 +/- 0.15) x 10(-18) cm(3) molecule(-1) s(-1) was derived. An upper limit of k less than or equal to 7 x 10(-21) cm(3) molecule(-1) s(-1) was established for the reaction of NO with cyclohexa- 1,3- diene. Benzene was observed as a product of both the OH and NO2 initiated oxidation, providing evidence of H atom abstraction in both reactions. Assuming the reaction of cyclohexadienyl radicals (C6H7) with O-2 produces benzene as the sole organic product, the results are consistent with abstraction channel branching ratios of (8.1 +/- 0.2)% and ( 1.5 +/- 0.4) respectively. The results also indicate that C6H7 reacts with NO2, with a relative rate coefficient k(C6H7 + NO2)/ k(C6H7 + O-2) = ( 1.8 +/- 0.5) x 10(5), and that this partially forms benzene, with a branching ratio of ( 27 +/- 7) The stoichiometry and products of the NO2 reaction were investigated in the absence of O-2, in the presence of O-2, and in the presence of O-2 and NO. Reaction mechanisms consistent with the observations are presented. In the presence of NO and O-2, the NO2-initiated chemistry leads to NO- to-NO2 conversion, and the formation of HOx radicals in significant yield, (0.79 +/- 0.05), such that cyclohexa- 1,3-diene removal occurs by reaction with both NO2 and OH. HCOOH was detected as a product in this system, providing evidence for significant formation of stabilised C-6 alpha-hydroxyperoxy radicals from the OH-initiated chemistry, and their subsequent reaction with NO. An estimate of ca. 500 - 1000 s(

Published
2005

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