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Hu, Q.*; Wang, Q. M.*; Zhang, T.*; Zhao, C.*; Iltaf, K. H.*; Liu, S. Q.*; 深津 勇太
Energy Reports (Internet), 9, p.3661 - 3682, 2023/12
This study evaluates petrophysical properties of representative geological rocks in the context of injectivity, storage space, and caprock integrity for effective utilization and long-term storage of carbon dioxide. A total of 10 geological rocks were selected as representative storage media for consideration as saline aquifers & depleted oil and gas reservoirs, basalts, and cap rocks, as well as utilization in organic-rich shale and coal seams. An integrated suite of laboratory tests, including liquid immersion porosimetry, gas expansion porosimetry, grain size distribution, mercury intrusion porosimetry, and gas diffusion, were performed on these various rock samples. The results exhibit a disparity of petrophysical properties among two broad groups of rocks: rocks selected for possible storage of CO have porosities of 10-25%, permeabilities of 10-10 m, m-sized pore-throat size distribution, and mostly good pore connectivity; in contrast, the potential caprocks have porosities of 0.5-5%, permeabilities of 10-10 m, pore throat sizes of 50 nm, and probably poorly connected pore networks. An understanding of the measured facets of pore structure and contribution of fractures is also critical in the context of different testing principles and data interpretation of petrophysical analyses, as well as observational scales in the laboratory and field, and therefore reliable confidence of CO storage and utilization performance. Our work further illustrates the controlling influence of grain size distribution and geological processes on pore size distribution and pore connectivity for a wide range of rock types and lithologies, and particularly presents the extent and behavior of CO gas diffusion with a custom-designed apparatus for a holistic understanding of various petrophysical attributes of widely different geological rocks.
Esser, S. P.*; Rahlff, J.*; Zhao, W.*; Predl, M.*; Plewka, J.*; Sures, K.*; Wimmer, F.*; Lee, J.*; Adam, P. S.*; McGonigle, J.*; et al.
Nature Microbiology (Internet), 8(9), p.1619 - 1633, 2023/09
被引用回数:1 パーセンタイル:83.33CRISPR-Cas systems defend prokaryotic cells from viruses, plasmids, and other mobile genetic elements. Capitalizing on multi-omics approaches, we show here that the CRISPR-Cas systems of uncultivated archaea also play an integral role in mitigating potentially detrimental interactions with episymbionts. A comprehensive analysis of CRISPR-Cas-based infection histories revealed that uncultivated deep-subsurface archaeal primary-producers defend themselves from archaeal episymbionts of the DPANN superphylum of archaea, some of which are known to fuse their membranes with their host. We show that host cells counter these attacks by deploying one of two CRISPR-Cas systems (type I-B and type III-A) to target and disrupt essential genes in the episymbiont. However, genome-scale modeling of metabolic interactions between two deep subsurface host-symbiont systems revealed that host cells also benefit from the symbionts via metabolic complementation. We speculate that populations of these uncultivated archaeal episymbionts are currently transitioning from a parasitic lifestyle to one of mutualism, as must have occurred in countless mutualistic systems known today. By expanding our analysis to thousands of archaeal genomes, we conclude that CRISPR-Cas mediated resistance to archaeal episymbiosis evolved independently in various archaeal lineages and may be a wide-spread evolutionary phenomenon.
Yuan, X.*; Hu, Q.*; Lin, X.*; Zhao, C.*; Wang, Q.*; 舘 幸男; 深津 勇太; 濱本 昌一郎*; Siitari-Kauppi, M.*; Li, X.*
Journal of Hydrology, 618, p.129172_1 - 129172_15, 2023/03
被引用回数:0 パーセンタイル:0(Engineering, Civil)Mass transport in geomedia as influenced by the pore structure is an important phenomenon. Six rocks (granodiorite, limestone, two chalks, mudstone, and dolostone) with different extents of heterogeneity at six different particle sizes were studied to describe the effects of pore connectivity on mass transport. The multiple methods applied were porosity measurement, gas diffusion test, and batch sorption test of multiple ions. Porosity measurement results reveal that with decreasing particle sizes, the effective porosities for the "heterogenous" group (granodiorite and limestone) increase, whereas the porosities of "homogeneous" group (chalks, mudstone, and dolostone) roughly remain constant. Gas diffusion results show that the intraparticle gas diffusion coefficient among these two groups, varying in the magnitude of 10 to 10 m/s. The batch sorption work displays a different affinity of these rocks for tracers, which are related to their mineral components. For granodiorite, mudstone, and dolostone, the adsorption capacity increases as the particle size decreases, due to higher specific surface area in smaller particle-size. In general, this integrated research of grain size distribution, rock porosity, intraparticle diffusivity, and ionic sorption capacity gives insights into the pore connectivity effect on both gas diffusion and chemical transport behaviors for different lithologies and/or different particle sizes.
Wang, Q.*; Hu, Q.*; Zhao, C.*; Yang, X.*; Zhang, T.*; Ilavsky, J.*; Kuzmenko, I.*; Ma, B.*; 舘 幸男
International Journal of Coal Geology, 261, p.104093_1 - 104093_15, 2022/09
被引用回数:3 パーセンタイル:72.03(Energy & Fuels)To understanding the spatial heterogeneity of mineral and pore structure variations in fine-grained shale, microscale X-ray fluorescence (micro-XRF) mapping, (ultra-) small-angle X-ray scattering [(U)SAXS] and wide-angle X-ray scattering were applied for two samples from a piece of Eagle Ford Shale in South Texas. Thin section petrography and field emission-scanning electron microscopy, X-ray diffraction (XRD), total organic carbon, and pyrolysis were also utilized to investigate the potential spatial heterogeneity of pore types, mineral and organic matter compositions for both samples. Overall, the siliceous-carbonate mineral contents in these carbonate-rich Eagle Ford Shale vary between laminations at mm scales. By analyzing six selected sub-samples on each of two samples with X-ray scattering and XRD techniques, nm-sized pores are mainly interparticle ones in the higher calcite regions, where the porosity is also relatively lower, while the lower calcite regions consist of both interparticle and intraparticle pore types with higher porosity. Finally, the micro-XRF and (U)SAXS are combined to generate porosity distribution maps to provide more insights about its heterogeneity related to the laminations and fractures at our observational scales.
Sheng, Q.*; 金子 竜也*; Yamakawa, Kohtaro*; Guguchia, Z.*; Gong, Z.*; Zhao, G.*; Dai, G.*; Jin, C.*; Guo, S.*; Fu, L.*; et al.
Physical Review Research (Internet), 4(3), p.033172_1 - 033172_14, 2022/09
A pyrite system NiSSe exhibits a bandwidth controlled Mott transition via (S,Se) substitutions in a two-step process: the antiferromagnetic insulator (AFI) to antiferromagnetic metal (AFM) transition at 0.45 followed by the AFM to paramagnetic metal (PMM) transition at 1.0. Among a few other Mott systems which exhibit similar two-step transitions, Ni(S,Se) is of particular interest because a large intermediate AFM region in the phase diagram would provide unique opportunities to study the interplay between the spin and charge order. By comparing and combining our muon spin relaxation studies and previous neutron scattering studies, here we propose a picture where the spin order is maintained by the percolation of "nonmetallic" localized and dangling Ni moments surrounded by S, while the charge transition from AFI to AFM is caused by the percolation of the conducting paths generated by the Ni-Se-Ni bonds.
鈴木 博人*; Zhao, G.*; 岡本 淳*; 坂本 祥哉*; Chen, Z.-Y.*; 野中 洋亮*; 芝田 悟朗; Zhao, K.*; Chen, B.*; Wu, W.-B.*; et al.
Journal of the Physical Society of Japan, 91(6), p.064710_1 - 064710_5, 2022/06
被引用回数:0 パーセンタイル:0(Physics, Multidisciplinary)The magnetic properties and the electronic excitations of the new diluted magnetic semiconductor BaK(ZnMn)As have been studied by X-ray magnetic circular dichroism (XMCD) and resonant inelastic X-ray scattering (RIXS). The sum rule analysis of the XMCD spectra indicates that the Mn atoms are in the high-spin configurations of , whereas the presence of competing ferromagnetic and antiferromagnetic interactions between the Mn ions reduces the net spin moment. Based on a comparison of the RIXS line shapes with those of GaMnAs, it is concluded that the ground state of Mn in BaK(ZnMn)As consists of both the and electron configurations.
Zhao, C.*; 鈴土 知明; 外山 健*; 西谷 滋人*; 井上 耕治*; 永井 康介*
Materials Transactions, 62(7), p.929 - 934, 2021/07
被引用回数:2 パーセンタイル:26.82(Materials Science, Multidisciplinary)Fe中のCuの拡散係数をこれまで測定されていなかった低い温度領域で測定することに成功した。拡散係数を測定する一般的な方法である拡散カップルは高温でしか適用できないため、本研究ではアトムプローブとCu析出の反応速度論を用いた。推定された拡散係数は、以前の研究で得られたものよりも信頼性が高いことが分かった。よって、アトムプローブによる推定がより高い精度をもたらしたと考えられる。さらに、この方法によって推定された拡散係数は、温度の低下に伴い多少オーバーエスティメイトされる傾向があることが、キネティックモンテカルロシミュレーションで明らかになった。
He, H.*; Naeem, M.*; Zhang, F.*; Zhao, Y.*; Harjo, S.; 川崎 卓郎; Wang, B.*; Wu, X.*; Lan, S.*; Wu, Z.*; et al.
Nano Letters, 21(3), p.1419 - 1426, 2021/02
被引用回数:28 パーセンタイル:94.81(Chemistry, Multidisciplinary)In CrCoNi, a so-called medium-entropy alloy, an fcc-to-hcp phase transformation has long been anticipated. Here, we report an in situ loading study with neutron diffraction, which revealed a bulk fcc-to-hcp phase transformation in CrCoNi at 15 K under tensile loading. By correlating deformation characteristics of the fcc phase with the development of the hcp phase, it is shown that the nucleation of the hcp phase was triggered by intrinsic stacking faults. The confirmation of a bulk phase transformation adds to the myriads of deformation mechanisms available in CrCoNi, which together underpin the unusually large ductility at low temperatures.
Tam, D. M.*; Song, Y.*; Man, H.*; Cheung, S. C.*; Yin, Z.*; Lu, X.*; Wang, W.*; Frandsen, B. A.*; Liu, L.*; Gong, Z.*; et al.
Physical Review B, 95(6), p.060505_1 - 060505_6, 2017/02
被引用回数:23 パーセンタイル:71.84(Materials Science, Multidisciplinary)We use neutron diffraction and muon spin relaxation to study the effect of in-plane uniaxial pressure on the antiferromagnetic (AF) orthorhombic phase in BaFeTAs and its Co- and Ni-substituted members near optimal superconductivity. In the low-temperature AF ordered state, uniaxial pressure necessary to detwin the orthorhombic crystals also increases the magnetic ordered moment, reaching an 11% increase under 40 MPa for BaFeCoAs, and a 15% increase for BaFeNiAs. We also observe an increase of the AF ordering temperature () of about 0.25 K/MPa in all compounds, consistent with density functional theory calculations that reveal better Fermi surface nesting for itinerant electrons under uniaxial pressure. The doping dependence of the magnetic ordered moment is captured by combining dynamical mean field theory with density functional theory, suggesting that the pressure-induced moment increase near optimal superconductivity is closely related to quantum fluctuations and the nearby electronic nematic phase.
Deng, Z.*; Zhao, K.*; Gu, B.; Han, W.*; Zhu, J. L.*; Wang, X. C.*; Li, X.*; Liu, Q. Q.*; Yu, R. C.*; 後神 達郎*; et al.
Physical Review B, 88(8), p.081203_1 - 081203_5, 2013/08
被引用回数:71 パーセンタイル:91.9(Materials Science, Multidisciplinary)We report the discovery of a diluted magnetic semiconductor, Li(Zn,Mn)P, in which charge and spin are introduced independently via lithium off-stoichiometry and the isovalent substitution of Mn for Zn, respectively. Isostructural to (Ga,Mn)As, Li(Zn,Mn)P was found to be a -type ferromagnetic semiconductor with excess lithium providing charge doping. First-principles calculations indicate that excess Li is favored to partially occupy the Zn site, leading to hole doping. Ferromagnetism with Curie temperature up to 34 K is achieved while the system still shows semiconducting transport behavior.
三木 一弘; Diamond, P. H.*; Fedorczak, N.*; Grcan, . D.*; Malkov, M.*; Lee, C.*; 小菅 祐輔*; Tynan, G. R.*; Xu, G. S.*; Estrada, T.*; et al.
Nuclear Fusion, 53(7), p.073044_1 - 073044_10, 2013/07
被引用回数:24 パーセンタイル:72.51(Physics, Fluids & Plasmas)LH, HL遷移の理解はITER運用の成否に重要である。この論文で我々は新たな理論モデル研究を紹介して、遷移の時空間ダイナミクスを調べる。ここで帯状流の役割、そしてダイナミクスと輸送しきい値の間にあるマクロとミクロの接続について強調する。モデルは5場で、簡略化された座標系で、時間と1次元の空間発展を解く。この論文の内容は次の通りである。(a)モデルの基礎方程式とLIH遷移の時空間発展、(b)Bドリフトの非対称性で輸送しきい値が変化することの物理的な説明、(c)熱雪崩現象がLIH遷移のしきい値変位に与える影響、(d)HL逆遷移のダイナミクスとヒステリシスの物理。
He, C.*; Shen, S.*; Wen, S.*; Zhu, L.*; Wu, X.*; Li, G.*; Zhao, Y.*; Yan, Y.*; Bai, Z.*; Wu, Y.*; et al.
Physical Review C, 87(3), p.034320_1 - 034320_10, 2013/03
被引用回数:5 パーセンタイル:38.74(Physics, Nuclear)High-spin states of Rb are studied via the fusion-evaporation reactions Cu+F, Zn+O, and Zn+O with the beam energies of 75 MeV, 76 MeV, and 80 MeV, respectively. Twenty-three states with twenty-eight transitions are added to the previously proposed level scheme, where the second negative-parity band is significantly pushed up to spins of 22 and 15 and two sidebands are built on the known first negative-parity band. Two successive band crossings with frequencies 0.51 MeV and 0.61 MeV in the = 0 branch as well as another one in the =1 branch of the second negative-parity band are observed. Signature inversions occur in the positive-parity and first negative-parity bands at the spins of 11 and 16, respectively. The signature splitting is seen obviously in the second negative-parity band, but the signature inversion is not observed. It is also found that the structure of the two negative-parity bands is similar to that of its isotone Y. Signature inversion in the positive-parity yrast band with configuration g9/2 g9/2 in this nucleus is discussed using the projected shell model.
Pitcher, C. S.*; Andrew, P.*; Barnsley, R.*; Bertalot, L.*; Counsell, G. G.*; Encheva, A.*; Feder, R. E.*; 波多江 仰紀; Johnson, D. W.*; Kim, J.*; et al.
Journal of Nuclear Materials, 415(Suppl.1), p.S1127 - S1132, 2011/08
被引用回数:0 パーセンタイル:0.01(Materials Science, Multidisciplinary)ITER plasma boundary and first-wall diagnostics are summarized in terms of their physical implementation and physics motivation. The challenge of extracting diagnostic signals while maintaining nuclear shielding is discussed, as well as the problems associated with high levels of erosion and redeposition.
広田 耕一; Zhao, C.*
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 56, 2008/03
ダイオキシン類分析廃液分解技術の開発を目的として、本研究では分析溶媒としてエタノール,n-ノナン,トルエン中8塩素化ダイオキシン(OCDD)の線分解挙動や毒性変化について調べた。その結果、OCDDの分解率はエタノールn-ノナントルエンの順となり、これが各溶媒中溶媒和電子の生成G値の大小関係と一致したことから、OCDDの分解には溶媒和電子が関与していることがわかった。また、0から8塩素化ダイオキシン類(PCDD)総濃度で分解率を比較すると、その順序はエタノールトルエンn-ノナンとなった。反応したOCDDの脱塩素化率がn-ノナン中で80%、トルエン中で20-30%であることから、n-ノナン中のOCDDは溶媒和電子との反応によりおもに脱塩素反応を起こし、低塩素化ダイオキシン類を生成するのに対し、トルエン中では酸化反応が支配的に起こることが明らかになった。
藤澤 彰英*; 井戸 毅*; 清水 昭博*; 岡村 昇一*; 松岡 啓介*; 井口 春和*; 浜田 泰司*; 中野 治久*; 大島 慎介*; 伊藤 公孝*; et al.
Nuclear Fusion, 47(10), p.S718 - S726, 2007/10
被引用回数:100 パーセンタイル:95.33(Physics, Fluids & Plasmas)帯状流の物理の実験的進展につきレビューする。新しい測定器により、プラズマ中の帯状流の存在が確認され、その時間空間特性,乱流や閉じ込めとの関係が明らかにされてきた。特に、測地的音波モードという振動帯状流について、測定結果が集積し、理論的進展をうながしている。乱流による帯状流の生成機構も解明されつつある。各国の装置の結果を比較,協力することにより、今後もなお一層、帯状流と閉じ込めとの関係の解明を進めることが重要である。
藤澤 彰英*; 井戸 毅*; 清水 昭博*; 岡村 昇一*; 松岡 啓介*; 浜田 泰司*; 星野 克道; 永島 芳彦*; 篠原 孝司; 中野 治久*; et al.
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 12 Pages, 2007/03
帯状流に関する実験の現状についてまとめる。測定の進歩により、帯状流の存在,時間空間特性,乱流との関係,閉じ込めとの関係などが明らかになりつつある。特に、帯状流の一種である測地的音波モードの測定結果の集積により、これを記述できる理論の構築が必要となっている。これらの帯状流と閉じ込めの解明をさらに進めるためには、装置間の横断的研究が非常に有効であると考えられる。
Zhao, C.; 広田 耕一; 田口 光正; 瀧上 真知子*; 小嶋 拓治
Radiation Physics and Chemistry, 76(1), p.37 - 45, 2007/01
被引用回数:11 パーセンタイル:66.25(Chemistry, Physical)ダイオキシン類の分析廃液の処分を目的とした、放射線処理技術を開発した。具体的には八塩素化ダイオキシンとフランの分解についてエタノール,ノナン及びトルエン溶媒中の分解挙動や分解生成物の同定を行った。この結果、同一線量では極性であるエタノール中の方が八塩素化ダイオキシンやフランが分解しやすいことがわかった。さらに、ノナン及びトルエン中のダイオキシンを含む分析有機廃液に、エタノールを加えて放射線照射を行うことにより、廃液中のダイオキシン類を90%分解し、毒性当量濃度を0にできることを明らかにした。
広田 耕一; Zhao, C.*; 小嶋 拓治; 星 正敏*
環境と測定技術, 33(8), p.23 - 28, 2006/08
近年のダイオキシン類の分析需要の増加により、ダイオキシン類分析機関には、現在多量のダイオキシン類分析廃液がPCB同様保管されている。有機溶媒廃液の最も一般的な処理法には焼却法があるが、処理施設の建設費用が膨大になるほか、処理プロセスが複雑でトラブルも発生しやすい。そこで、既存のCo線照射施設を活用して、分析廃液に0-160kGyの範囲で線を照射し、ダイオキシン類を無毒化する技術の開発を行った。ノナン,トルエン,エタノールを溶媒として、8塩素化ダイオキシン及びフランを溶解させた各模擬分析廃液に照射を行った結果、エタノールが最も毒性低減に優れていることがわかった。低塩素化異性体の濃度変化解析の結果、エタノール中ダイオキシン及びフランは、低吸収線量域では脱塩素を、高吸収線量域では酸化分解を起こすことが明らかになった。そこで、分析実廃液をエタノールで100倍希釈し、100kGy照射したところ、ダイオキシン類を毒性換算でほぼ100%、モル換算で90%で分解することに成功した。また、この条件下でコスト試算を行い、3Lの分析廃液の場合、5万円程度で処理が可能であることを明らかにした。
Martin, A. J.*; 梅田 浩司; Conner, C. B.*; Weller, J. N.*; Zhao, D*; 高橋 正樹*
Journal of Geophysical Research; Solid Earth, 109(B10), p.B10208_1 - B10208_20, 2004/10
被引用回数:60 パーセンタイル:73.16(Geochemistry & Geophysics)将来の火山活動は、過去の地質学的データ(火山の位置、噴火年代等)によって予測が試みられているが、データが不足している地域については予測結果に対する信頼性が十分でない。そのため、地震波速度構造や地温勾配分布等の地球物理学的データを基に、ベイズ法によって将来の火山活動を予測する手法の検討を行った。
Zhao, D. Q.*; Pan, M. X.*; Wang, W. H.*; Wei, B. C.*; 岡田 卓; 内海 渉
Journal of Physics; Condensed Matter, 15(50), p.L749 - L753, 2003/12
被引用回数:9 パーセンタイル:31.91(Physics, Condensed Matter)NdAlFeCo組成のバルク金属ガラスの高圧下における融解並びに結晶化を放射光を用いたその場エックス線回折実験により観測した。その結果、圧力は、結晶化を促進し、融解を抑制する方向に作用することが明らかとなった。