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尾瀬ヶ原は日本最大の高山泥炭湿原であり，貴重な泥炭生態系として保全されてきた．しかし20世紀後期からニホンジカの侵入と豪雨による洪水による生態系の攪乱が顕在化してきた．本稿では二酸化炭素（CO2）やメタン（CH4）放出に関する既往の研究と尾瀬ヶ原湿原におけるニホンジカの攪乱が及ぼす影響を概観する．尾瀬ヶ原，中田代の5か所，14地点で2019年6～10月の5か月間に土壌およびガス試料を採取・分析した．攪乱によるアンモニア態窒素の増加が認められた．非攪乱地のCO2やCH4放出は8月に極大が見られ攪乱地より多かった．CO2やCH4放出量は地下水位と負の相関関係が見られ，尾瀬ヶ原におけるニホンジカの攪乱が地下水位と泥炭土壌の理化学性および温室効果ガスの放出に顕著な影響を及ぼしていることが示された．, Ozegahara mire is the largest alpine mire in Japan. The mire has been preserved as a precious peatland ecosystem with high ecological diversity. After the late 20th century, the mire has been exposed to ecosystem disturbance by mire flooding due to heavy rain as well as invasive Sika deer. This manuscript reviewed studies about greenhouse gas emission from wetland and report the effects of Sika deer disturbance on the soil physicochemical properties and the emission of carbon dioxide (CO2) and methane (CH4) from Ozegahara mire. Soil and gas samples were collected at fixed 14 fixed plots on 5 sites with and without mire disturbance by Sika deer in Naka-tashiro of Ozegahara mire through 5 months of 2019 (June to October), and determined their properties and gas composition each month. Groundwater level displayed similar seasonal change in two sites, being affected by precipitation. The concentrations of NH4+ nitrogen in the disturbed sites were higher than those in the undisturbed sites. Mechanical disturbance of the peat soils by deer resulted in mineralization of organic matter. CO2 and CH4 fluxes from the undisturbed sites were highest in August, and those were higher than those from the disturbed sites. Negative correlation was found between CO2 and groundwater level and also correlation between CH4 and groundwater level was negative, suggesting the importance of groundwater level in greenhouse gases flux, depending on the sites and also species of greenhouse gases.

メタンハイドレートは、日本周辺の海底に大量に存在し、現在の資源不足を補う代替エネルギーとして注目されている。また、化石燃料に比べて、二酸化炭素や有害物質の排出量が少ないことから、その有効性はかなり期待されている。そこで、平成28年に発行された中学校「理科」の教科書と高校「化学基礎」・「化学」の教科書の記載箇所における記述・学習内容を調査し、その中でメタンハイドレートがどのように扱われているかを調査した。調査の結果、中学校の教科書では、「新エネルギー」として扱う一方で、「科学・技術」の分野でも記載されていた。高校の教科書では「巻末特集」や「有機化合物」でメタンCH4に関係するものとして取り上げられていることが分かった。既存の教科書において、メタンハイドレートは既に一般的な用語となっているものの、出版社によっては説明が足りない内容もあった。そのため、メタンハイドレートを理解し、エネルギーや技術・開発について関心を持つために、生徒が体感できる教材を製作することが必要であると考えている。

過去の大気中メタン濃度の復元をするため、アイスコアに含まれる気体中のメタン濃度をアイスコア連続融解システム（CFA）で測定している。CFAは、アイスコアを連続的に融解・測定するシステムで、従来の手法に比べ格段に高分解能かつ測定時間の短縮という点で優れた手法である。これまでに得られているCFAを用いたメタンの連続データは、最終氷期以降のもののみであり、それ以前のものは得られていない。国立極地研究所では、最終氷期以前の大気中メタンの連続記録を復元するため、深さ2400m（過去約30万年間）までのドームふじコアをCFAで測定していく予定である。CFAを用いた先行研究から、大気に由来しないメタンがアイスコア中に含まれることが明らかになってきた(Rhodes et al., 2013）。過去の大気由来のメタンの変動を正確に復元するためには、非大気由来のメタンの特徴や原因を調べる必要がある。そのため、NEEMサイトと同じグリーンランド北西部に位置するSIGMA-Dサイトで掘削されたコアのCFA分析を行った。NEEMサイトと類似して比較的気温が高く不純物濃度が高いSIGMAサイトでは、より大きなメタンの上昇がみられた。それらについて、同時に測定された氷中の不純物などとの比較や原因の議論を行う。一方、ドームふじ基地のような低涵養かつ不純物の少ない南極内陸高原部のメタンの連続データは未だ得られておらず、堆積現場で生成されるメタンの影響があるのかは明らかでない。このようなコアでは、ガスが気泡として取り込まれるまでに時間がかかるため、大気の変動が100年オーダーでスムージングされて保存されている（Spahni et al., 2003）。そこで、他のコアのデータが豊富に得られている時代についてドームふじコアの測定を行い、スムージングや氷床内でのメタン生成について調査する必要がある。現在までに深さ300～332mの測定を実施した。この深度範囲は気体の年代で7600年から8800年前に相当し、大気中メタンの濃度変動が平坦な時期と、8200年前に大きく濃度減少した時期を含んでいる。CFA分析の結果から、大気中のメタン濃度が変化しない時期のデータには、グリーンランドのコアに見られたようなメタン生成の兆候は見られなかった。大気中メタン濃度が大きく変動した8200年前付近には、大気中の濃度変動を示すトレンドに重なって、大気由来とは思われない細かい周期的変動がみられた。その振幅は10 ppb程度であり、周期は深度で10 cｍ程度である。この細かい変動は、もともと気体が氷床に閉じ込められる深度域（フィルンの底部）における密度のムラによって生じている可能性がある。フィルンの氷化深度域の上部と下部で形成された気泡に閉じ込められる空気の年代は100年スケールで異なるため、深度方向に隣り合った層が通気を失う深度が異なる場合、それらの層に含まれる空気の年代が平均的に異なることになる。したがって、氷床内の空気の年代が深度方向に入れ替わることが考えられ、その効果が、大気のメタン濃度が急速に変化した時代の測定データとして現れたと考えられる。今回得られた結果は、今後ドームふじコアをCFAで測定した結果から過去の大気を復元していく際に、データ解釈をしていくうえで欠かせない知見である。, Polar Meteorology and Glaciology Group seminar / 気水圏コロキウム 日時：3月22日（水）11:00-11:50 場所：C301（3階セミナー室）

The specific surface area (SSA) of snow is of particular interest to researchers because SSA is strongly related to snow albedo and is a comparatively better indicator of snow’s complexity than grain size. The time variation of SSA for fresh snow samples was observed in the laboratory under isothermal conditions at 226 K and 254 K using the gas adsorption method and Brunauer-Emmett-Teller theory. The SSA of the snow samples decreased with time under isothermal metamorphism. The decrease in SSA was fitted with the logarithmic equation proposed by Legagneux et al. (2003), and adjustable parameters were obtained. The rate of decrease in SSA depended on the shape of the initial snow type and temperature. Dendritic snow samples exhibited large initial SSAs, and their SSAs decreased faster compared with those of fragmented (collected from drifting snow) and plate-like precipitation particles with relatively small initial SSAs. The rate of decrease in SSA was lower at 226 K than that at 254 K.

In this examination, we studied on the correlation of between the methane discharge of expiration and rumen using cattle fitted with rumen fistula was fed by general breeding method. We corrected gas from expiration and rumen at five times in before feeding, after feeding, after an hour of feeding, after three hours of feeding, and after five hours of feeding. The amount of methane discharge was tended to increase immediately after feeding. And then, the amount of methane discharge was gradual decreased. We observed positive correlation between expiration and rumen for methane discharge., 本試験では、一般的な飼養法で飼育されているフィステルを装着した牛を用いて呼気中へのメタン排出量とルーメン内のメタン生成量の関連性について検討した.呼気およびルーメン内のガスの採取は，給餌直前，給餌直後，給餌後約1時間後，給餌後約3時間後，給餌後約5時間後の計5回行った.両者のメタン量を計測したところ，飼料給餌直後にメタン量が増加し，その後漸減していく傾向が見られた.また，呼気およびルーメン内のメタン量は高い正の相関があることが確認された.

In this examination, we studied on the correlation of between the methane discharge of expiration and rumen using cattle fitted with rumen fistula was fed by general breeding method. We corrected gas from expiration and rumen at five times in before feeding, after feeding, after an hour of feeding, after three hours of feeding, and after five hours of feeding. The amount of methane discharge was tended to increase immediately after feeding. And then, the amount of methane discharge was gradual decreased. We observed positive correlation between expiration and rumen for methane discharge., 本試験では、一般的な飼養法で飼育されているフィステルを装着した牛を用いて呼気中へのメタン排出量とルーメン内のメタン生成量の関連性について検討した.呼気およびルーメン内のガスの採取は，給餌直前，給餌直後，給餌後約1時間後，給餌後約3時間後，給餌後約5時間後の計5回行った.両者のメタン量を計測したところ，飼料給餌直後にメタン量が増加し，その後漸減していく傾向が見られた.また，呼気およびルーメン内のメタン量は高い正の相関があることが確認された., 紀要論文

北方の湿地やツンドラは, 地球の全土壌炭素の約30％が蓄積する場であり, メタンの主要発生源である. 本稿では, 積雪が北方の湿地におけるメタン放出やメタンの代謝に関わる微生物に及ぼす影響を概説, 以下のように要約した. １）積雪によって冬期のメタン放出量は低下するが, その間湿地土壌中にメタンが蓄積し, 春の融雪とともに急激に大気へ放出される. ２）積雪による保温効果や不凍水における栄養塩やその他基質の濃縮効果により, 微生物の活性が高くなる. ３）大気との遮断や地下水位の上昇により湿地土壌中の嫌気環境が拡大しメタン生成が促進される. ４）積雪の影響は冬季ばかりでなく夏季のメタン放出にも及ぶ., Northern wetland and tundra regions store approximately 30% of the world organic soil carbon and function as a major source of atmospheric methane. In this article, the impact of snow on methane emission and microorganisms in northern wetlands is reviewed. In summary, 1)Methane emission from northern wetland is reduced in winter partly by snowpack and methane is accumulated in the soil under snow;snow melt causes a “burst”of methane emission in spring. 2)Microbial activities in wetland soil are enhanced by snow cover that keeps the underlying surface soil warmer (around 0 ℃) and causes concentrated nutrients and substrates for microorganisms in unfrozen soil water. 3)Snow pack suppresses gas exchange between wetland soil and the atmosphere and melted snow may raise the level of water table, both of which expand anoxic area in soil and enhance methane production. 4)Snow can also give an impact on methane emission in a vegetative season of summer.

北方圏に広がる自然湿地は, 温室効果気体である大気メタンの重要な放出源である. これらの湿地は１年の半分近くが積雪に覆われるものの, 冬期における湿地からのメタン放出過程についてはよくわかっていない. 本報では, 湿地のメタン生成・消費と大気への放出およびそれらに影響を及ぼす環境因子（土壌温度, 湿地植生, 水位変動, 氷板, 積雪の変質過程）について, とくに積雪期における過程に注目しながら解説した. また, 先行研究で得られた知見をもとに, 今後の湿地観測の重要性と研究手法について議論した., Northern wetlands are one of the most important sources of atmospheric methane,a potent greenhouse gas with about 20 times the global warming potential of carbon dioxide. Although snow can cover the surface of northern wetlands for more than half the year,most attention has been given to methane emission from wetlands during the growing season. Here I review studies that have addressed the microbial methane production, methane oxidation,and gas transfer processes in both wetland soils and the overlaying snow cover to understand the processes of winter methane emission from northern wetlands. I emphasize,based on the findings of those studies, that there is a need for a great deal of intensive and extensive monitoring of methane dynamics in snow-covered wetlands in northern ecosystems.

In the present study, the effects of microbial material solution (MMS) including phototrophic purple bacteria(PPB) on methane( CH4) production from submerged soil were investigated. Seven treatments were set up: sterilizedor un-sterilized MMS was added to paddy soil with and without rice straw which were also sterilized or unsterilizedand then they were incubated at 30℃ for 4 weeks after submergence in the tube. CH4 and carbon dioxide(CO2) production were significantly higher in the treatment with unsterilized soil added with rice straw comparedto treatment with sterilized soil added with rice straw and treatment without rice straw. In the 2 treatments withunsterilized soil added with rice straw, the treatment with unsterilized MMS was significantly lower methane emissionand was detected higher PPB compared to the treatment with sterilized MMS. The accumulation of organicacids in both standing water and soil was little in the treatment where CH4 and CO2 emission were higher and thetreatment without rice straw. In contrast, the accumulation of organic acids increased in the treatment with sterilizedsoil added rice straw. These results implied the possibility that the CH4 emission which resulted from decompositionof rice straw via organic acids under submerged soil was mitigated when MMS including PPB was added,probably due to competition between methanogens and PPB for organic acids as substrates.

In this examination, we studied on the measurement technique of amount of methane discharged from cattle. Instrument for measurement of methane was made from methane sensor (MQ-4), core circuit, and sending circuit. Influence of the temperature and the humidity to the sensor value was considered. It was admitted the interaction of the temperature and the humidity to the sensor value. And we got multiple regression numerical formula; Rs /RO = 1.022905 -0.03702^* Temp(℃) - 0.081^* Hum(%) (R2=0.973). There is a possibility of measurement of concentration of methane more correctly attached the value obtained from numerical formula., 本試験では様々な飼養環境下において，牛が排出するメタンの量を直接計測可能なシステムの開発を行い、ルーメン内に投入し，連続的にルーメン内で生成されるメタン量を計測可能なラジオカプセル法について検討した.今回，供試したメタンセンサーでは，温度および湿度の変化にともない，センサー値が変化することが認められ，これらの関係に重回帰が認められ，より正確な近似式を用いることで，メタンの計測が可能となるものと推察された., 紀要論文

The carbon storage capacity of grassland soils is greater than that of cropland, but grassland management changes the amounts of methane (CH_4) and nitrous oxide (N_2O) emitted from soils. To investigate the effects of forage species, renovation, and farmyard manure (FYM) application on CH_4 and N_2O emissions from grassland soils, substantiative experiments were performed on grassland plots in Nasu, Japan. The experiments are described in this thesis as follows. Chapter 3 describes the effects of forage species composition on CH_4 and N_2O emissions. Orchardgrass (OG), white clover (WC), and OG/WC grasslands emitted -1.8, -2.4, and -1.8 kg CH_4 -C ha^-1 year^-1 and 0.39, 1.59, and 0.67 kg N_2O -N ha^-1 year^-1, respectively. WC increased the permeability of the soil to air but did not significantly increase annual CH_4 consumption by grassland soil, although it did significantly increase annual N_2O emissions from the soil. Chapter 4 investigates the effect of grassland renovation on N_2O emissions. Renovated plots emitted 2.1 to 5.3 kg N ha^-1 and unrenovated control plots emitted 0.96 to 2.8 kg N ha^-1. Grassland renovation significantly increased N_2O emission from the soil. In the renovated plots, N was mineralized from incorporated roots and stubble, and the soil moisture was distributed within the range favorable for N_2O production and emission. Greater N_2O emission was observed with increasing soil moisture just before renovation and with precipitation just after renovation. Chapter 5 describes the effects of FYM application on CH_4 and N_2O emissions from grassland soils. Grassland plots that received FYM plus chemical fertilizer (manure plot) or chemical fertilizer only (fertilizer plot) were compared. In both plots, the sum of N applied as fertilizer and N estimated to be mineralized from FYM was adjusted to 210 kg ha^-1 year^-1. The manure plot emitted 7.0 to 11.0 kg N_2O -N ha^-1 year^-1 and the fertilizer plot emitted 4.7 to 9.1 kg N_2O -N ha^-1 year^-1. FYM application significantly increased annual N_2O emissions from the grassland soil. The manure plot emitted -0.74 to -0.16 kg CH_4 -C ha^-1 year^-1 and the fertilizer plot emitted -0.84 to -0.52 kg CH_4 -C ha^-1 year^-1. FYM application did not significantly increase annual CH_4 emissions. These results show that, to mitigate N_2O emissions from grassland soils, it is important to reduce the amount of N fertilizer applied in accordance with the amount of N fixed by WC and N mineralized from FYM. It is also important not to renovate grassland at a time of year when soil temperature and soil moisture are relatively high., 草地は畑地より炭素貯留機能が大きいが, 草地管理は温暖化係数の高いメタン (CH_4) や亜酸化窒素 (N_2O) の排出量を変化させる。本研究は, 草種構成, 草地更新, 堆肥散布が CH_4 と N_2O の排出量に及ぼす影響を明らかにするため, 那須の火山灰土壌の草地において実証試験を行った。第3章では, 草地の草種構成が CH_4 と N_2O の排出量に及ぼす影響を述べた。オーチャードグラス (OG) 単播草地, シロクローバ (WC) 単播草地, OG/WC 混播草地の CH_4 と N_2O の排出量は, それぞれ -1.8, -2.4, -1.8kg C ha^-1 y^-1, 0.39, 1.59, 0.67kg N ha^-1 y^-1 であった。WC は土壌通気性を高めたが CH_4 年間吸収量を有意に増加させなかった。WC が栽培されると N_2O 年間排出量が有意に増加した。第4章では, 草地更新時の N_2O 排出量を述べた。草地更新を行った草地 (更新草地) と行わない草地 (対照草地) の N_2O 排出量は, それぞれ 2.1～5.3, 0.96～2.8kg N ha^-1 で草地更新は N_2O 排出量を有意に増加させた。更新草地では, すき込まれた根と刈株から窒素無機化が起こり, 土壌水分は N_2O が生成され易く, また排出され易い領域に分布した。更新時期の土壌水分や更新直後の降雨量が多いと N_2O 排出量が増加した。第5章では, 堆肥散布が草地からの N_2O と CH_4 の排出量に及ぼす影響を述べた。堆肥と化学肥料を散布した草地 (堆肥区) と化学肥料のみを散布した草地 (化学肥料区) の N_2O と CH_4 の排出量を比較した。なお, 両処理区の窒素供給量は 210kg N ha^-1 y^-1 に調整した。堆肥区と化学肥料区の N_2O 年間排出量は, それぞれ 7.0～11.0, 4.7～9.1kg N ha^-1 y^-1で堆肥散布が N_2O 年間排出量を増加させた。堆肥区と化学肥料区の CH_4 年間排出量は, それぞれ -0.74～-0.16, -0.84～-0.52kg C ha^-1 y^-1 で堆肥散布は CH_4 年間排出量を増加させなかった。以上の結果から, N_2O 排出量を抑制するため, WC の窒素固定や堆肥の無機化を考慮して施肥量を削減し, 地温や土壌水分の高い時期を避けて更新を行うことが重要と指摘される。

不法投棄物や最終処分場の埋立廃棄物の掘削現場において，ハンディタイプオープンパス型メタン自動計測器によって連続計測したppmレベルの大気中メタン濃度を指標とする作業環境の有害ガス簡便モニタリング手法を提案し，掘削現場への適用可能性を検討した。不法投棄現場や最終処分場から発生するガス中の有害ガスはメタンと共存すること，有害ガスとして注目されるのは硫化水素である場合が多いこと，硫化水素のメタンに対する濃度比の最大値は10^[-1]程度であることを示し，大気中メタン濃度が発生ガス中の有害ガスの潜在的な危険性を安全側で評価する指標になることを明らかにした。また，掘削現場での影響が懸念される硫化水素等の有害ガスの許容濃度，有害ガスのメタンに対する濃度比の最大値および安全率を考慮して設定したメタン濃度の管理値を計測値と比較する提案手法が，掘削現場の安全管理のためのモニタリングに適用できることを示した。, We propose a convenient method for monitoring hazardous gas based on the determination of ppm-level concentrations of CH4 in ambient air. The proposed method can be applied during the excavation of landfill or dumped waste at reclamation sites, and we investigated its usability in an actual field. A portable open-path type analyzer and a retroreflector were used to determine the CH4 concentration. The hazardous gas in landfill gas emitted from final disposal and illegal-dumping sites always contains CH4 and H2S occurring together, with the latter considered to be the main hazardous component. The maximum concentration ratio (H2S/CH4) at final disposal and illegal-dumping sites was expected to be about 10^[-1]. This study showed clearly that the ambient CH4 concentration could be useful as an indicator for the monitoring of hazardous gas for the evaluation of potential danger. It was also shown that the proposed method could be useful for monitoring as a safety control at a reclamation site. This method works by comparing the measured ppm concentration levels of CH4 with a management value that is decided by considering the maximum concentration ratio (of the hazardous gas that was most harmful at the site, such as H2S/CH4), its acceptable concentration and a safety ratio.

The objective of this study was to measure methane emission from beef cattle cows fed hay or whole crop rice silage (WCS) and to determine the reduction rate in methane emission due to the addition of rice bran or steam flaked corn (corn) at a maintenance energy intake level. Methane emission per dry matter intake level (DMI) of Japanese Black cows fed rice WCS harvested at the yellow-ripe stage was 33L/kg DMI, which was higher than that of cows fed hay harvested at the flower stage (28L/kg DMI). However methane emissions per digestible organic matter or digestible energy were not significantly different between cows fed hay and cows fed rice WCS. Feeding 2 kg of rice bran or corn, 30% of the ration with rice WCS decreased methane emission per DMI, and the degree of reduction for rice bran was larger than that for corn. Ruminal propionate proportions in cows fed rice WCS were lower than those for hay feeding. The addition of rice bran or corn to rice WCS increased the ruminal propionate proportion. Methane emissions from cows with a high ruminal propionate proportion tended to decrease. The results demonstrate that feeding corn or rice bran with rice WCS is effective for decreasing methane emission from cows., 黒毛和種繁殖雌牛に黄熟期収穫のイネホールクロップサイレージ (イネWCS) を維持量給与した場合のメタン産生量は、摂取乾物 (DM) 1kg当たり33Ｌ／kgで、開花期収穫の乾草の28L／kgよりも有意に高かった。しかし、可消化有機物および可消化エネルギー当たりでは有意な差ではなかった。イネWCSの維持量給与水準において米ヌカまたは蒸煮圧片トウモロコシを原物で2kg、添加割合で30%給与することにより、摂取DM当たりのメタン産生量は低下し、その低下の程度は米ヌカの方が大きかった。第一胃液のプロピオン酸モル比はイネWCS給与は乾草給与に比べて低いが、米ヌカまたはトウモロコシを添加するとその比は高まった。プロピオン酸モル比の高い飼料の方がメタン産生量は少ない傾向にあった。本試験より、イネWCS給与において、トウモロコシもしくは米ヌカの添加はメタン産生量の減少に有効であることが認められた。

Dependency of static stability of the Jovian atmospheres on the abundances of condensible elements is considered by calculating the moist adiabatic profiles. Optimal minimization method of Gibbs free energy which developed by Sugiyama et al. (2001) is utilized to obtain equilibrium compositions in order to cover a variety of basic elements. It is shown that CH4 is the most dominant contributor in producing a stable layer in the Uranian atmosphere. In the cloud layer of the Jovian atmosphere, the proportional law of static stability to H2O mole fraction, which is assumed by Achterberg and Ingersoll (1989), does not hold when the H2O mole fraction is larger than about 5 x solar. The value of static stability obtained for the Jovian cloud layer is too small to explain the phase velocity of the SL9 (Shoemaker-Levy 9) impact wave as that of an internal gravity wave., 資料番号: AA0063350037

This study presents numerical simulation results of combustion dynamics in a lean premixed combustor. The combustor is a swirl-stabilized gas turbine model combustor installed at Aerospace Research Center (ARC), Japan Aerospace Exploration Agency (JAXA). The methane/air lean premixed gas is used at the preheated temperature of 700 K, pressure 1 atm and equivalence ratio 0.5. Without control, large pressure oscillations are observed in the combustor mostly with longitudinal acoustic modes. The basic mode is quarter-wave mode. The pressure waves induce periodical vortex shedding from the combustor dump plane, thus changing, the flame shape and location. This leads to temporal and spatial fluctuations in heat release rate, and the Rayleigh index, the correlation between pressure and heat release fluctuations, indicates that these fluctuations are coupled to sustain combustion oscillations. Secondary fuel injection control is introduced to charge the coupling between these factors. This numerical simulation succeeds in reproducing reduced combustion oscillations with constant injection of 3 percent fuel through the swirler hub injection ports. The change in flame shape is reproduced and the reduced amplitude can be attributed to the change in heat release distribution as the Rayleigh index implies. Thus, it is expected that the amplitude may be reduced further when injection phase control is additionally introduced with a feedback control system, and this is our future research subject., 資料番号: AA0049212011, レポート番号: JAXA-SP-05-017

資料番号: AA0063347004

Increase of energy consumption with an increase of global population has brought out change of climate, plant and ecological system all over the world. It is said that the exhaustion of petroleum will come near future. One of the best measures for this energy crisis was the construction of the solar power satellites (SPS) which supply electric power through microwave to the ground in a high efficiency. It is anxious for this ultra-big project that a vast heat and propellant should be discharged in each launch of scalar array segments, sub-structures and materials and makes remarkable influences on the global environment surrounding human lives. If most of the space power stations could be made on the moon by using lunar resources and transported to the geostationary orbit, energy consumption for the transportation and the influence on the global environment would be much reduced. An initial fundamental equipment, facilities and chemical media or materials should be carried from the ground to the moon. There are many processes to produce solar cell and structures. All technologies of production and transportation seem to be realized with great difficulties. However, a launch system on the moon like a linear motor on the ground and the transportation systems are already partially utilized. Each production process needs much energy and power. Robots in various shapes suitable for performing the processes play important roles. They need no food and can work to construct production plant, power station and factory by feeding electric energy. At first, regolith should be gathered and put into a special reactor with reducing agent, for example, hydrogen. If water could found on the moon pole, it would play an important role, of course, for the life support as well as the production of scalar cell, structure materials, etc. Furthermore, if a robot could produce another robot as well as many other facilities, devices and materials, production system would grow in both its system and production scale. None of such automatic production methods has been studied, but these production system can be realized after a century or so by continuous research and developments in cooperation of many scientific and technical fields all over Japan and the world., 資料番号: AA0049120009

資料番号: AA0046920010

資料番号: AA0047898044

The origin of the strong interstellar 217.5 nm absorption feature appearing in the interstellar extinction curve is a long-standing problem in astrophysics. In the present study, by a simple method, soot with sharp absorption features around 220 nm was produced from methane gas. Interestingly, it was found that the absorption peak positions of the present soot can be controlled by the production temperature. Analyzed results of soot by high-resolution electron microscope clarified that the origin of the absorption peak at 217.5 nm was a graphitic structure with a diameter of 5 nm order., 資料番号: AA0046650066

New spectrum of the Pluto is presented, covering the 2.8-4.1 micrometer wavelength range. The new data show prominent absorptions of ethane ice on surface of Pluto. The present results require the mass ratio of ethane to methane to be approximately 1:10, which is much higher than the value expected from the equilibrium condensation theory. Three processes are proposed to add this surplus ethane to Pluto's surface: 1) external reservoir, 2) internal reservoir, and 3) photolysis/radiolysis. The present study could provide important implications and constraints for evolutions of the edge of the solar system, such as Pluto, Charon, and EKBOs., 資料番号: AA0046650044

application/pdf, The purpose of this study was to evaluate the effect of anerobically co-digested dairy manure and food processing wastes as an organic fertilizer, and to investigate the changes in soil nitrogen and grain yield of winter wheat (Hokushin) comparing digested dairy manure with chemical fertilizer. By the incubation test, it was clear that the NH4-N was almost converted into the NO3-N for four weeks. Over the period of 101 days, 15% of inorganic N was accumulated in the soil. Between grain yields where co-digested dairy manure and chemical fertilizer were applied, there were no significant difference, but protein contents in grain were higher in co-digested manure applied than chemical fertilizer one (p

Recently, great concern has gathered in generating from the livestock farm of environmental load gases, such as ammonia (NH₃), nitrous oxide (N₂0) and methane (CH₄). In order to calculate the total amount of each gas per capita which occurs from swine waste, three processes considered to be the main generation sources of each gas was examined. According to the results of those experimental studies, 1）The NH₃(NH₃-N), N₂0(N₂0-N) and CH₄ emissions from pig units during a full fattening period of 8 weeks were estimated at 149, 5.8 and 302g/head respectively. 2）The NH₃ (NH₃-N), N₂0 (N₂0-N)and CH₄ emissions from swine wastewater purification were estimated at negligible, l.8～7.4g and 10.7～37.5g/head respectively. 3) The NH₃ (NH₃-N）, N₂0 (N₂0-N) and CH₄ emissions from compost were estimated at 133～325g, 0.2～129g and 0.7～6.4g/head respectively. 4) The NH₃-N, N₂0-N and CH₄ emissions from the swine keeping unit and its manure contributes (a full fattening period of 8 weeks) were estimated at 271～438, 16.5～49.4 and 270～438g/head respectively. And, 5) Those emission could be reduced by adequate manure contributes, such as ; weekly discharge of slurry in swine unit, employment of intermittent aeration process for wastewater treatment and keeping of aerobic condition during swine manure composting., 標準的な養豚経営の単位家畜あたりのふん尿由来の環境負荷ガス発生総量を算定し，その抑制条件を検討した。肥育全期間中(8週間，20kg～80kgの増体期間)に畜舎内でアンモニア（NH₃)，亜酸化窒素(N₂0) およびメタン（CH₄）が先生する量は，それぞれ181，9.1および302g/頭と試算された。豚ふん尿汚水浄化処理からの放出推定値として，NH₃については検出限界以下、CH₄については1.8～7.4g CH₄/頭，N₂0については10.7-37.5g N₂0-N/頭の発生が試算された。堆肥化過程からの放出推定値として発生はNH₃が133～ 325gNH₃-N／頭，CH₄が0.2～129gCH₄/頭およびN₂0が0.7～6.4gN₂0-N/頭と試算された。発生抑制には，NH₃については肥育豚舎からの放出抑制と堆肥化過程からの物理的捕集，N₂0については間欠曝気法の適用，CH₄については堆肥化を好気的条件で行うことが有効と考えられた。

都市域とその周辺における大気微量成分(大気メタン・オゾン)濃度の観測・解析結果について示す:前半は, 台風襲来時のオゾン・大気メタン濃度分布の解析結果を, 後半では, これまでの解析・推定結果の確認および周辺域(バックグラウンド)の濃度調査のために, 佐久島(三河湾)や伊勢湾・三河湾海上での空気試料採取とその分析結果について示す。後半の結果は, これまでの解析から推定してきた濃度分布(作業仮説モデル)の妥当性を示唆している。, In the first part we analyze the spatial distribution and its temporal variation of the atmospheric methane and ozone in Kyoto-shi, the southern part of Kyoto-fu and its surrounding region when the typhoon hit the Kinki district.Secondly, in order to confirm the earlier result of the subjective analyses over the sea surrounded by the land urban area, we made several observations (air-sampling and gas-chromatographic analysis) at Sakushima located in the middle of Mikawa Bay; and the Atsumi-Peninsura; and from the experimental cruise by the Seifu-Maru of the University of Mie, we preliminarily examined the concentration of the atmospheric methane in Ise- and Mikawa-Bay.

東京に近い相模湾上空の対流圏大気を採取、分析し、主要温室効果ガスおよびその他の化学的に重要な反応性ガスの垂直分布を得た。本文では、1997年2月から1998年2月までの1年間に毎月2回づつ収集したデータを解析し、検討した。これらのデータから、以下に述べるような重要な観測事実が明らかになった、(1)温室効果ガスのほとんどはよく混合されており、2km以上の高度では比較的均一であった。CO2、CH4およびCOは一般に2km以下の高度において高い濃度を示したが、これは恐らく地上の人工源からのものと思われた、(2)CO2濃度の平均値は対流圏界面付近で定期航空機が採取したデータとかなりよく一致した、および(3)N2Oの大気中での変動は高度や季節に関係なく最も小さかった。また、重要反応性化学種の1つであるCOは対流圏気層を通じて非常に大きな変動を示し、定性的にはCH4の濃度と類似の傾向を示した。, Tropospheric air over Sagami-Bay near Tokyo, was sampled and analyzed to obtain vertical distributions of major greenhouse gases and other chemically important reactive gases. Data collected twice a month for a year from February 1997 to February 1998 were analyzed and are discussed here. These data revealed the following important observational facts. (1) Most greenhouse gases are well mixed and relatively uniform above 2 km; CO2, CH4 and CO showed generally high concentration at altitudes below 2 km, presumably from artificial sources on the ground. (2) Averaged CO2 concentration corresponds fairly well with the data obtained by airline sampling near tropopause. (3) N2O has the least variation in the atmosphere independent of altitude and season, and one of the important reactive species, CO, has quite a wide variation across the tropospheric layer and qualitatively similar concentration tendencies to CH4., 資料番号: AA0001970000, レポート番号: NAL TM-745

A differential absorption lidar (light detection and ranging) system is developed as methane leakage detector using 1.67μm absorption band. A detection range of various 100m and 1000ppm・m is estimated by numerical calculation, and 30m resolution of detection is demonstrated experimentally. Since amplifier noise and telescope misalignment spoil the sensitivity and the range of the system, solutions are also proposed. Development of a compact optical parametric oscillator for a transmitter injection-seeded by a laser diode is also reported.

本報告では以下の項目についての研究成果を述べる;(1)大気中のオゾンの測定法とその精度, 成層圏オゾンの光化学, 成層圏から対流圏へのオゾンの輸送, 地上オゾンに対する光化学と自由対流圏からの輸送の寄与。(2)対流圏の水蒸気と二酸化炭素の温室効果の比較, 成層圏の水蒸気の分布・季節変化, (3)都市域でのメタンの発生源と発生強度, Results on the following subjects are reported; (1) the method and accuracy of the measurements of atmospheric ozone, the photochemistry of stratospheric ozone, the transport of stratospheric ozone into the troposphere, effects of vertical transport and the chemical production/destruction on the surface ozone(2) greenhouse effects of tropospheric water vapor and carbon dioxide, the distribution and seasonal variation of stratospheric water vapor; (3) the sources and emission strength of methane in the urban areas.

クライオサンプリング装置を大気球に搭載し, 1985年から1995年までの期間, 日本上空において成層圏空気の採集を実施した。得られた試料空気を分析することにより, 温室効果気体として重要なCO_2,CH_4,N_2Oの濃度およびCH_4のδ^Cの鉛直分布を明らかにした。CO_2濃度は, 圏界面付近から20∿25km以上の等濃度層まで, 高度と共に急速に低下し, その差は4∿8ppmvであった。しかし, CO_2濃度が減少する層や等濃度となる高度は一定しておらず, その原因は, 成層圏下部での極側への大気輸送が年や季節によって異なること, あるいはジェット気流付近での大気の鉛直混合にあると考えられる。等濃度層におけるCO_2濃度は年々増加しており, その平均的な増加率は1.50 (±0.04)ppmv/yearであった。CH_4およびN_2Oの濃度は, 成層圏での活発な消滅のために, 圏界面直上のおよそ1750ppbvおよび311ppbvから35km付近の550∿900および30∿70ppbvまで, 高度と共に急激に減少していた。CH_4のδ^Cは, CH_4濃度の減少とあいまって, 圏界面直上の約-47‰から35kmでの約-39‰へと高度と共に急激に増加していた。観測されたδ^Cの鉛直分布は, 主にCl原子との消滅反応に起因するものと考えられた。, Stratospheric air samples have been collected over Japan during the period from 1985 to 1995 using a balloon-borne cryogenic sampler, and then analyzed for the CO_2,CH_4 and N_2O concentrations and the carbon isotopic ratio of CH_4. The results showed that the CO_2 concentration decreased with height in an interval from the tropopause to 20-25km, and then became almost constant values above this level. The concentration differences between the lowermost part of the stratosphere and heights above 20-25km amounted to 4-8 ppmv. The lower stratospheric CO_2 showed different profiles for different measurements, probably due to annually- and seasonally-dependent poleward air transport and vertical mixing of stratospheric air near the jet stream. An average increase rate of the stratospheric CO_2 concentration was estimated to be 1.50 (±0.04) ppmv/year from the data above 20-25km. The CH_4 and N_2O concentrations decreased rapidly from about 1750 and 311 ppbv at the tropopause to 550-900 and 30-70 ppbv at 35km, respectively, due to their strong destruction through photolysis and chemical reactions. δ^C value of CH_4 increased markedly with height, from -47‰ just above the tropopause to about -39‰ at 35km, which is quite opposite to the vertical profile of the CH_4 concentration. It was strongly suggested that the destruction of CH_4 by the reaction with Cl atoms is responsible for this steep vertical profile of δ^C., 資料番号: SA0167086000

資料番号: AA0063352007

Simultaneous Particle Image Velocimetry/OH Planar Laser Induced Fluorescence (PIV/OH-PLIF) was used to measure the conditional unburned and burned velocities in turbulent premixed methane-air flames. The flames used were stabilized through a balance between the burning velocity and incoming flow, hence without a recirculation zone or stagnation plate. The turbulent intensity as well as the temperature at the inlet could be changed, so that turbulent scalar fluxes (mu double prime times c double prime averaged) were measured at a velocity ratio (u prime/S(sub L)) ranging from 1 to 5 and a heat release factor from 2 to 5. Turbulence characteristics were obtained using Particle Image Velocimetry technique under reacting conditions, for both turbulent velocity and integral length scale and the OH-PLIF signal provided the scalar information to distinguish between burned and unburned gases. The measurements of the scalar fluxes were evaluated using different processing techniques from PIV and the effects of the grid and processing methods are first discussed. In the present investigation, both counter gradient diffusion and gradient diffusion were measured. Preheated mixtures lead to gradient diffusion due to the lower thermal expansion. Non-preheated flames exhibited counter gradient diffusion behavior except for flames with the lowest equivalence ratio. Comparisons with classical transition criterion based on Bray and modified Bray numbers were not successful for the present data set. Therefore, to correctly predict the transition between gradient and counter-gradient diffusion, a modification to the criterion taking into account pressure gradients effects was proposed. This criterion was also successfully tested with previously published results for which the integral length scales were smaller so as to encompass a wider range of turbulence scales. Furthermore, three different fuels (methane, propane and hydrogen) were used to obtain the new transition, validating the approach over a wide range of situations., 資料番号: AA0063456000, レポート番号: JAXA-RR-06-020E

研究科: 千葉大学大学院自然科学研究科

研究科: 千葉大学大学院自然科学研究科

Chapter1 Literature Review||Chapter2 Increased Biogas and Biomethane Production from OPEFB and OPMF Supplementation||Chapter3 Microbiota Analysis||Chapter4 Sustainable Biogas to Bioenergy||Chapter5 Concluding Remarks and Suggestions for Future Research, 九州工業大学博士学位論文 学位記番号:生工博甲第191号 学位授与年月日:平成24年12月31日, 平成24年度

研究科: 千葉大学理学研究科, 修了年:2008