A Case Study of Risk Assessment of Ozone Impact on Forest Tree Species in Japan

Watanabe, Makoto,Yamaguchi, Masahiro,Matsumura, Hideyuki,Kohno, Yoshihisa,Koike, Takayoshi,Izuta, Takeshi Korean Society for Atmospheric Environment 2011 Asian Journal of Atmospheric Environment (AJAE) Vol.5 No.4

Ozone ($O_3$) is a main component of photochemical oxidants and a phytotoxic air pollutant. Although the current levels of tropospheric $O_3$ in East Asia could adversely affect productivity of forest tree species, risk assessments of $O_3$ impact were limited. In this paper, we summarize the methodology of risk assessment of $O_3$ on forest tree species based on our two previous studies, risk assessments of $O_3$ impact on the growth of Fagus crenata by Watanabe et al. (2012) and on the annual carbon absorption of three representative conifers, Cryptomeria japonica, Pinus densiflora and Larix kaempferi by Watanabe et al. (2010). $O_3$ sensitivity of each tree species obtained from an experimental study, $O_3$ exposure and atmospheric N deposition based on field monitoring and vegetation survey were integrated by geographic information system method. Based on the results, we conclude that the area with high risk of $O_3$ impact does not necessarily correspond to the area with high $O_3$ exposure. The varieties of tree habitat, tree sensitivity to $O_3$ and annual carbon absorption among the tree species, and N deposition-induced change in the $O_3$ sensitivity of F. crenata are raised as the factors of discordance between areas with high risk and those with high $O_3$ exposure. In the last part of this paper, we discuss the present uncertainty and perspectives of risk assessment for the future studies on the impact of $O_3$ on forest tree species in East Asia.

A Case Study of Risk Assessment of Ozone Impact on Forest Tree Species in Japan

Makoto Watanabe,Masahiro Yamaguchi,Hideyuki Matsumura,Yoshihisa Kohno,Takayoshi Koike,Takeshi Izuta 한국대기환경학회 2011 Asian Journal of Atmospheric Environment (AJAE) Vol.5 No.4

Ozone (O_3) is a main component of photochemical oxidants and a phytotoxic air pollutant. Although the current levels of tropospheric O_3 in East Asia could adversely affect productivity of forest tree species,risk assessments of O_3 impact were limited. In this paper, we summarize the methodology of risk assessment of O_3 on forest tree species based on our two previous studies, risk assessments of O_3 impact on the growth of Fagus crenata by Watanabe et al. (2012) and on the annual carbon absorption of three representative conifers, Cryptomeria japonica, Pinus densiflora and Larix kaempferi by Watanabe et al. (2010). O_3 sensitivity of each tree species obtained from an experimental study, O_3 exposure and atmospheric N deposition based on field monitoring and vegetation survey were integrated by geographic information system method. Based on the results, we conclude that the area with high risk of O_3 impact does not necessarily correspond to the area with high O_3 exposure. The varieties of tree habitat, tree sensitivity to O_3 and annual carbon absorption among the tree species, and N deposition-induced change in the O_3 sensitivity of F. crenata are raised as the factors of discordance between areas with high risk and those with high O_3 exposure. In the last part of this paper, we discuss the present uncertainty and perspectives of risk assessment for the future studies on the impact of O_3 on forest tree species in East Asia.

Experimental Study on Adjustment of Inlet Nozzle Section to Flow Rate Variation for Darrieus-type Hydro-Turbine

Watanabe, Satoshi,Shimokawa, Kai,Furukawa, Akinori,Okuma, Kusuo,Matsushita, Daisuke Korean Society for Fluid machinery 2012 International journal of fluid machinery and syste Vol.5 No.1

A two dimensional Darrieus-type turbine has been proposed for the hydropower utilization of extra-low head less than 2m. In a practical use of Darrieus-type hydro-turbine, head and flow rate may be varied temporally and seasonally. Considering that the cost advantage is required for the low head hydro turbine system, the Darrieus turbine should be operated with high efficiency in the wider range of flow rate possibly by using an additional device with simpler mechanism. In the present paper, an adjustment of inlet nozzle section by lowering the inlet nozzle height is proposed to obtain the preferable inlet velocity in low flow rate conditions. Effects of resulting spanwise partial inlet flow are investigated. Finally, an effective modification of inlet nozzle height over flow rate variation is shown.

Measurement and Correlation of Isobaric Vapor-Liquid Equilibria for Binary and Ternary Systems Containing Methyl Tertiary Butyl Ether (MTBE), Methanol and Alkanes

Watanabe, Toru,Honda, Katsumi,Arai, Yasuhiko 한국화학공학회 2003 Korean Journal of Chemical Engineering Vol.20 No.5

Isobaric vapor-liquid equilibria (VLE) of four binary systems--methyl tertiary butyl ether (MTBE)+methanol. MTBE+heptane, MTBE+octane and MTBE+i-octane--were measured at atmospheric pressure by using Othmer-type circulation method. The VLE of ternary system. MTBE+methanol+heptane, were also measured at atmospheric pressure. These VLE data were predicted by ASOG and correlated by Wilson equation, and the prediction and correlation performances were discussed.

Dark aerobic methane emission associated to leaf factors of two Acacia and five Eucalyptus species

Watanabe, M.,Watanabe, Y.,Kim, Y.S.,Koike, T. Pergamon Press ; Elsevier [distribution] 2012 Atmospheric environment Vol.54 No.-

We sought the biological factors determining variations in the methane emission rates from leaves of different plant species under aerobic conditions. Accordingly, we studied relations between the methane emission rate and leaf traits of two Acacia and five Eucalyptus species. We grew seedlings of each species in a glasshouse and measured the methane emission rate of the detached leaves under dark conditions at 30 <SUP>o</SUP>C. At the same time we measured the leaf mass per area (LMA), water content, and concentrations of carbon and nitrogen. There was no correlation between the leaf nitrogen concentration and the methane emission rate. This is consistent with previous findings that enzymatic processes do not influence methane emission. We found a significant negative correlation between LMA and the methane emission rate. Our results suggest that leaf structure is primarily responsible for differences in the rates of aerobic methane emission from leaves of different species.

Japanese-North Korean Relations and Korean Unification

Watanabe Akio 한양대학교 아태지역연구센터 1994 중소연구 Vol.18 No.4

Choked Surge in a Cavitating Turbopump Inducer

Watanabe, Toshifumi,Kang, Dong-Hyuk,Cervone, Angelo,Kawata, Yutaka,Tsujimoto, Yoshinobu Korean Society for Fluid machinery 2008 International journal of fluid machinery and syste Vol.1 No.1

During an experimental investigation on a 3-bladed and a 4-bladed axial inducer, a severe surge instability was observed in a range of cavitation number where the blade passage is choked and the inducer head is decreased from noncavitating value. The surge was stronger for the 4-bladed inducer as compared with a 3-bladed inducer with the same inlet and outlet blade angles. For the 4-bladed inducer, the head decreases suddenly as the cavitation number is decreased. The surge was observed after the sudden drop of head. This head drop was found to be associated with a rapid extension of tip cavity into the blade passage. The cause of surge is attributed to the decrease of the negative slope of the head-flow rate performance curve due to choke. Assuming that the difference between the 3 and 4-bladed inducers is caused by the difference of the blockage effects of the blade, a test was carried out by thickening the blades of the 3-bladed inducer. However, opposite to the expectations, the head drop became smoother and the instability disappeared on the thickened blade inducer. Examination of the pressure distribution on both inducers could not explain the difference. It was pointed out that two-dimensional cavitating flow analyses predict smaller breakdown cavitation number at higher flow rates, if the incidence angle is smaller than half of the blade angle. This causes the positive slope of the performance curve and suggests that the choked surge as observed in the present study might occur in more general cases.

Internal Flow and Limiting Streamlines Observations of Contra-Rotating Axial Flow Pump at Partial Flow Rate

Watanabe, Satoshi,Momosaki, Shimpei,Usami, Satoshi,Furukawa, Akinori Korean Society for Fluid machinery 2011 International journal of fluid machinery and syste Vol.4 No.2

An application of contra-rotating rotors, in which a rear rotor is in tandem with a front one and these rotors rotate in the opposite direction each other, has been proposed against a demand for developing higher specific speed axial flow pump. One prototype rotors, which we have designed with a conventional method, has given the positive slope of head characteristic curve especially in the rear rotor. It is necessary to understand the internal flow behavior in the rear rotor to establish the design guideline for achieving higher and more reliable performance. In the present study, we carried out the experimental investigations of the internal flow field of the rear rotor, especially at the partial flow rate, by Laser Doppler Velocimetry (LDV) for the main flow and the limiting streamlines observation on rotor surfaces for the boundary layer flows.

Radiotherapy for non-gastric intestinal versus gastric MALT lymphoma: a comparison of treatment outcomes

Watanabe Shigenobu,Ogino Ichiro,Hata Masaharu 대한혈액학회 2020 Blood Research Vol.55 No.4

Background Radiotherapy is often used for treating patients with gastric mucosa-associated lymphoid tissue (MALT) lymphomas who fail to respond to Helicobacter pylori eradication. However, non-gastric intestinal MALT lymphoma is rare, and no standard therapeutic strategies have been established. This study was designed to assess the long-term prognosis of non-gastric intestinal MALT lymphoma treated with radiotherapy and to compare the outcomes with that of post-radiotherapy gastric MALT lymphoma. Methods The study included 34 patients with stage I EA gastrointestinal MALT lymphoma according to the Ann Arbor classification who underwent definitive radiotherapy. The primary site was the rectum in 3, the duodenum in 1, and the stomach in 30 patients. The radiotherapy dose was 1.5‒2.0 Gy (median, 1.5 Gy) and the total dose was 30‒40 Gy (median, 30 Gy). The clinical target volume (CTV) was defined as the volume of the entire organ with the lymphoma. Adjacent lymph node areas were not routinely included in the CTV. Results Complete response (CR) was achieved in all patients. There were no local recurrences, and two cases of recurrence were observed at other sites. The 5-year overall survival rates for non-gastric and gastric MALT lymphomas were 100% and 94.7%, respectively, and the 5-year disease-free survival rates were 100% and 95.7%, respectively. None of the patients died of the current illness. Conclusion Radiotherapy for non-gastric intestinal MALT lymphoma is expected to result in good local control and long-term survival, similar to that for gastric MALT lymphoma.

Viscoelastic and Dielectric Relaxation of Reptating Type-A Chains Affected by Reversible Head-to-Head Association and Dissociation

Watanabe, Hiroshi,Matsumiya, Yumi,Kwon, Youngdon American Chemical Society 2018 Macromolecules Vol.51 No.16

<P>For entangled linear polymer having type A dipoles and undergoing head-to-head association and dissociation reaction, viscoelastic and dielectric behavior is theoretically analyzed on the basis of the reptation dynamics combined with the reaction kinetics. Specifically, for the dissociated unimer and associated dimer (indexed with <I>j</I> = 1 and 2, respectively), the normalized complex modulus <I>g</I><SUB><I>j</I></SUB>*(ω) and the normalized complex dielectric permittivity ε̃<SUB><I>j</I></SUB>*(ω) are analytically calculated via eigenfunction expansion of the orientational anisotropy and orientational memory defined in terms of the bond vectors <B>u</B> of entanglement segments. The reaction activates mutual conformational transfer between the unimer and dimer. Multiple coupling occurs for the anisotropy decay modes of the unimer and dimer due to this transfer, and the viscoelastic <I>g</I><SUB>1</SUB>* and <I>g</I><SUB>2</SUB>* of the unimer and dimer, respectively, exhibit considerably retarded and accelerated relaxation compared to the pure reptation case. In contrast, the memory decay modes of the unimer and dimer are only pairwisely coupled, so that the reaction-induced acceleration and retardation for the dielectric ε̃<SUB>1</SUB>* and ε̃<SUB>2</SUB>* are much weaker than those seen for the viscoelastic <I>g</I><SUB>1</SUB>* and <I>g</I><SUB>2</SUB>*. The orientational anisotropy is the tensorial, second-moment average of <B>u</B> associated with no cancellation in the conformational transfer, whereas the orientational memory is the vectorial, first-moment average accompanied by partial cancellation, which results in the difference between <I>g</I><SUB><I>j</I></SUB>* and ε̃<SUB><I>j</I></SUB>*. This difference between <I>g</I><SUB><I>j</I></SUB>* and ε̃<SUB><I>j</I></SUB>* is noted also for the associating/dissociating Rouse chains. Nevertheless, the reaction-induced retardation of the viscoelastic relaxation is stronger for the reptating unimer than for the Rouse unimer, whereas the reaction-induced acceleration is similar, in magnitude, for the reptating dimer and Rouse dimer. These features of <I>g</I><SUB><I>j</I></SUB>* of the unimer and dimer are discussed in relation to the motional coherence along the chain backbone being present and absent in the reptation and Rouse dynamics.</P> [FIG OMISSION]</BR>