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Effects of radiation dose rate, electron energy and oxygen on disinfection of sewage sludge cake were studied to obtain technological information on disinfection by radiation. Sludge films were irradiated with electron beams at different voltages and various dose rates in oxygen-containing and oxygen-free atmospheres. Without oxygen, the surviving fraction of bacteria decreased with increasing irradiation dose, but depended little on the sludge film thickness. No effects of dose rate and energy change were found in the ranges from 20 kGy/h to 65 MGy/h and from 0.5 to 2.0 MeV when the film was thin enough to allow electron beam penetration. Similar results were obtained with γ-ray irradiation. In the oxygen-containing atmosphere, higher disinfection efficiency was obtained with thinner films and lower dose rates.

ポリ塩化ビニル繊維の熱酌性質を向上させるため,種々の試みが行なわれている。桜田らはポリ塩化ビニル繊維にアクリ獄ニトリルのグラフト重合を行ない,耐熱性が著しく向上することを報告している。本報告では放射線同時照射法により,ポリ塩化ビニル繊維にアクリロニトリルをグラフト重合させる反応について,線量率の影響を検討した。照射は未延伸のポリ塩化ビニル繊維をアクリロニトリルモノマーとn-ヘキサンとの1:1の混含液中に浸漬した状態で行ない,線源としては低線量率(104～106rad/hr)を得るため60℃を用い,高線量率(107～10grad/hr)を得るため電子線加速器を用いた。その結果,次の点が明らかになった。(1)低線量率でも高線量率でも容易に100%程度のグラフト率が得られるが,特に高線量率の場合2～3分の短い反応時間で達成される。(2)グラフト重合反応の初期速度は低線量率では線量率の1次に比例し,高線量率では線量率の増加とともに0.3次から0次へと変化する。(3)グラフト重合反応の初期速度の温度依存性は小さい。(4)グラフト重合反応の後重合効果は非常に小さい。(5)グラフト効率は高線量率で反応を行なった方が高い。(6)雰囲気の影響は反応のごく初期にのみ観測される。

By considering trade-offs and complementarity between carbon removal from the atmosphere by forests and emission reduction by wood use, we developed a forest-sector carbon integrated model for Japan. We discuss mitigation measures for Japan based on model projections. The integrated model included the forest model and the wood use model. Based on three scenarios (baseline, moderate increase, and rapid increase) of harvesting and wood use, the integrated model projected mitigation effects including carbon removal by forests and emission reduction through the wider use of wood, until 2050. Results indicate that forests will not become a source of net carbon emissions under the three scenarios considered. The baseline scenario is most effective for mitigating climate change, for most periods. However, the sum total of carbon removal in forests and carbon emission reductions by wood use under the rapid increase scenario exceeded the one of the moderate increase scenario after 2043. This was because of strong mitigation activities: promoting replanting, using new high-yield varieties, and wood use. The results also indicated that increases in emission reduction due to greater wood use compensated for 67.9 % of the decrease of carbon removal in 2050, for the rapid increase scenario. The results show that carbon removal in forests is most important in the short term because of the relative youth of the planted forests in Japan, and that mitigation effects by material and energy substitution may become greater over the longer term.

We present a calculation of the nucleon sigma term on two-flavor QCD configurations with dynamical overlap fermions. We analyse the lattice data for the nucleon mass using the baryon chiral perturbation theory. Using partially quenched data sets, we extract the connected and disconnected contributions to the nucleon sigma term separately. Chiral symmetry on the lattice simplifies the determination of the disconnected contribution. We find that the strange quark content, which determines the neutralino dark matter reaction rate with nucleon through the Higgs boson exchange, is much smaller than the previous lattice results., 7 pages, 6 figures, Talk given at 26th International Symposium on Lattice Field Theory (Lattice 2008), Williamsburg, Virginia, 14-20 Jul 2008

We extract the charm quark mass and the strong coupling constant from the charmonium current correlators calculated with $n_f = 2 + 1$ Mobius domain wall fermions. We match our lattice calculation for the temporal moments of the correlator with perturbative result known up to four-loop order, and extract the charm quark mass with uncertainty less than 1%. Using the temporal moments, we also confirm the correlators in the vector channel to be consistent with the experimental data for the R-ratio. We used the ensembles generated by the JLQCD collaboration at lattice spacings $a$ = 0.080 fm, 0.055 fm and 0.044 fm., Comment: 7 pages, 3 figures, Talk presented at the 34th annual International Symposium on Lattice Field Theory (LATTICE 2016), 24-30 July 2016, University of Southampton, UK

In this talk, I present my personal view on the status of lattice QCD calculations. I emphasize the role played by the chiral perturbation theory (ChPT) in analyzing the lattice data of various physical quantities, including chiral condensate, topological susceptibility, and pion mass and decay constant. I then discuss on the status of determination of fundamental parameters and other quantities of phenomenological interest., 8 pages, to appear in the proceedings for the XXIX Physics in Collision International Symposium, Kobe, Japan, August 30 - September 2, 2009. The title is modified on the arxiv version

We calculate the spectral function of the QCD Dirac operator using the four-dimensional effective operator constructed from the Mobius domain-wall implementation. We utilize the eigenvalue filtering technique combined with the stochastic estimate of the mode number. The spectrum in the entire eigenvalue range is obtained with a single set of measurements. Results on 2+1-flavor ensembles with Mobius domain-wall sea quarks at lattice spacing ~ 0.08 fm are shown., 7 pages, 4 figures, presented at the 33rd International Symposium on Lattice Field Theory, 14 -18 July 2015, Kobe, Japan

We study the $U(1)_A$ anomaly in two-flavor lattice QCD at finite temperature with the M\"obius domain-wall Dirac operator. We generate gauge configurations in the temperature range $(0.9, 1.2) T_c$ on different physical volumes, $L=$ 2--4 fm, and lattice spacings. We measure the difference of the susceptibilities of the flavor non-singlet scalar ($\chi_\delta$) and pseudoscalar ($\chi_\pi$) mesons. They are related by an axial $U(1)$ transformation and the difference vanishes if the axial $U(1)$ symmetry is respected. We identify the source of axial $U(1)$ symmetry breaking at finite temperature in the lowest eigenmodes, for the observable $\chi_\pi - \chi_\delta$. We then reweight the M\"obius domain-wall fermion partition function to that of the overlap-Dirac operator to fully recover chiral symmetry. Our data show a significant discrepancy in the results coming from the M\"obius domain-wall valence quarks, the overlap valence quarks on our DWF configurations and the reweighted ones that have full chiral symmetry. After recovering full chiral symmetry we conclude that the difference $\chi_\pi - \chi_\delta$ shows a suppression in the chiral limit that is compatible with an effective restoration of $U(1)_A$ at $T \gtrsim T_c$ in the scalar meson channels.

We determine the topological susceptibility \chi_t in the topologically-trivial sector generated by lattice simulations of N_f = 2+1 QCD with overlap Dirac fermion, on a 16^3 x 48 lattice with lattice spacing ~ 0.11 fm, for five sea quark masses m_q ranging from m_s/6 to m_s (where m_s is the physical strange quark mass). The \chi_t is extracted from the plateau (at large time separation) of the 2-point and 4-point time-correlation functions of the flavor-singlet pseudoscalar meson \eta', which arises from the finite size effect due to fixed topology. In the small m_q regime, our result of \chi_t agrees with the chiral effective theory. Using the formula \chi_t = \Sigma(m_u^{-1} + m_d^{-1} + m_s^{-1})^{-1} by Leutwyler-Smilga, we obtain the chiral condensate \Sigma^{MSbar}(2 GeV) = [249(4)(2) MeV]^3., Comment: 7 pages, 3 figures, talk presented at the XXVI International Symposium on Lattice Field Theory, July 14-19, 2008, Williamsburg, Virginia, USA

We calculate perturbative renormalization constants for the $\ensuremath{\Delta}B=2$ four-quark operators in lattice NRQCD. Continuum operators $\overline{b}{\ensuremath{\gamma}}_{\ensuremath{\mu}}(1\ensuremath{-}{\ensuremath{\gamma}}_{5})q\overline{b}{\ensuremath{\gamma}}_{\ensuremath{\mu}}(1\ensuremath{-}{\ensuremath{\gamma}}_{5})q$ and $\overline{b}(1\ensuremath{-}{\ensuremath{\gamma}}_{5})q\overline{b}(1\ensuremath{-}{\ensuremath{\gamma}}_{5})q,$ which are necessary in evaluating the mass and width differences in ${B}_{d(s)}^{0}\ensuremath{-}{B}_{d(s)}^{0}$ systems, are matched at one loop with corresponding lattice operators constructed from the NRQCD heavy quarks and the $\mathcal{O}(a)$-improved light quarks. Using these perturbative coefficients, we also reanalyze our previous simulation results for the matrix elements of the above operators. Our new results are free from the systematic error of $\mathcal{O}({\ensuremath{\alpha}}_{s}{/(aM}_{b}))$ in contrast with the previous ones with matching coefficients evaluated in the static limit.

The topology conserving gauge action proposed by Luescher is expected to reduce the number of non-smooth gauge configurations as well as the topology change compared to the conventional actions for the same lattice spacings. We report our quenched QCD study of the topological stability and the scaling violation of the static quark potential. We find that the the topology change is indeed suppressed when the parameter epsilon is of order one. We also find that the scaling violation in the static quark potential remain reasonably small in the parameter range of our study. Our study is done at the inverse lattice spacing a^{-1}=1.4-2.5 GeV with the lattice size L=1.0-1.6fm., Typos corrected. Talk presented at Lattice 2005 (topology and confinement), 6 pages, 5 figures

A simple method to analyze a small volume of CO 2 gas concentration is proposed. In this method, the sample gas volume is increased with air of known CO 2 concentration and is analyzed using an infrared gas analyzer. This method can be used in the field and laboratory.

We present a study for the pion decay constant fπ in the quenched approximation to lattice QCD with the Kogut-Susskind (KS) quark action, with the emphasis given to the renormalization problems. Numerical simulations are carried out at the couplings β=6.0 and 6.2 on 32^3×64 and 48^3×64 lattices, respectively. The pion decay constant is evaluated for all KS flavors via gauge invariant and noninvariant axial vector currents with the renormalization constants calculated by both the nonperturbative method and perturbation theory. We obtain fπ=89(6) MeV in the continuum limit as the best value using the partially conserved axial vector current, which requires no renormalization. From a study for the other KS flavors we find that the results obtained with the nonperturbative renormalization constants are well convergent among the KS flavors in the continuum limit, confirming restoration of SU(4)A, flavor symmetry, while perturbative renormalization still leaves an apparent flavor breaking effect even in the continuum limit.

In this study, we developed a new method for evaluating vertical profiles of CO 2 gas diffusivity and CO 2 gas production in soil samples. The CO 2 flux at the boundary and the steady-state CO 2 gas profile are measured under two boundary gas conditions. The differential form of Pick's second law can then be used to calculate the gas diffusion coefficients and CO 2 production rate. This method was applied to an undisturbed forest soil sample in the laboratory. Both gas diffusion coefficients and CO 2 production rates decreased with increasing depth. The relative gas diffusion coefficients ranged between 0.03 and 0.15, and the CO 2 production rates ranged between 2.1 X 10 -8 and 4.7 X 10 -8 kg CO 2 m 3 s -1 at 20°C. Unsteady changes in the CO 2 concentration profile in the soil column, and flux from the soil surface were successfully simulated with these values.

We report results of masses and decay constants of light and charmed pseudo-scalar mesons using lattice QCD with M\"obius domain-wall fermions. Using this formulation we are able to compute pseudo-scalar decay constants through the pseudo-scalar density operator as well as with the axial-vector current. Results are shown from several lattice spacings and pion masses between 230 MeV and 500 MeV. We present an analysis of these results at different quark masses to show the chiral properties of the light mesons masses and decay constants., Comment: 7 pages, 4 figures, Proceedings of the 33rd International Symposium on Lattice Field Theory (Lattice 2015)

We consider the simulation of finite temperature QCD with two flavors of dynamical overlap fermions in order to study the suppression of the axial U(1) symmetry breaking at the chiral phase transition point. As a preliminary study, pure gauge simulations are performed to investigate how fixing the topology affects physical quantities like the topological susceptibility, $\chi_t$, at finite temperature, showing that it is possible to reconstruct known results from the fixed topology sector. First results on the degeneracy of meson correlators in the high temperature QGP sector are shown., Comment: 7 pages, 4 figures. XXIX International Symposium on Lattice Field Theory, July 10 - 16 2011, Squaw Valley, Lake Tahoe, California

The global forest carbon (C) stock is estimated at 662 Gt of which 45% is in soil organic matter. Thus, comprehensive understanding of the effects of forest management practices on forest soil C stock and greenhouse gas (GHG) fluxes is needed for the development of effective forest-based climate change mitigation strategies. To improve this understanding, we synthesized peer-reviewed literature on forest management practices that can mitigate climate change by increasing soil C stocks and reducing GHG emissions. We further identified soil processes that affect soil GHG balance and discussed how models represent forest management effects on soil in GHG inventories and scenario analyses to address forest climate change mitigation potential. Forest management effects depend strongly on the specific practice and land type. Intensive timber harvesting with removal of harvest residues/stumps results in a reduction in soil C stock, while high stocking density and enhanced productivity by fertilization or dominance of coniferous species increase soil C stock. Nitrogen fertilization increases the soil C stock and N2O emissions while decreasing the CH4 sink. Peatland hydrology management is a major driver of the GHG emissions of the peatland forests, with lower water level corresponding to higher CO2 emissions. Furthermore, the global warming potential of all GHG emissions (CO2, CH4 and N2O) together can be ten-fold higher after clear-cutting than in peatlands with standing trees. The climate change mitigation potential of forest soils, as estimated by modelling approaches, accounts for stand biomass driven effects and climate factors that affect the decomposition rate. A future challenge is to account for the effects of soil preparation and other management that affects soil processes by changing soil temperature, soil moisture, soil nutrient balance, microbial community structure and processes, hydrology and soil oxygen concentration in the models. We recommend that soil monitoring and modelling focus on linking processes of soil C stabilization with the functioning of soil microbiota. This review has been supported by the grant Holistic management practices, modelling and monitoring for European forest soils – HoliSoils (EU Horizon 2020 Grant Agreement No 101000289) and the Academy of Finland Fellow project (330136, B. Adamczyk). In addition to the HoliSoils consortium partners, Dr. Abramoff contributed on this study and her work was supported by the United States Department of Energy, Office of Science, Office of Biological and Environmental Research. Oak Ridge National Laboratory is managed by UT-Battelle, LLC, for the United States Department of Energy under contract DE-AC05- 00OR22725.