DESIGN AND TEST PLAN OF THE SUPERCRITICAL CO 2 COMPRESSOR TEST LOOP

ABSTRACT Supercritical carbon dioxide (CO 2 ) gas turbine systems can generate power at a high cycle thermal efficiency, even at modest temperatures of 500-550°C. That high thermal efficiency is attributed to a markedly reduced compressor work in the vicinity of critical point. In addition, the reaction between sodium (Na) and CO 2 is milder than that between H 2 O and Na. Consequently, a more reliable and economically advantageous power generation system can be created by coupling with a Na-cooled fast breeder reactor. In a supercritical CO 2 turbine system, a partial cooling cycle is employed to compensate a difference in heat capacity for the high-temperature -low-pressure side and low-temperaturehigh-pressure side of the recuperators to achieve high cycle thermal efficiency. In our previous work, a conceptual design of the system was produced for conditions of reactor thermal power of 600 MW, turbine inlet condition of 20 MPa/527°C, recuperators 1 and 2 effectiveness of 98%/95%, Intermediate Heat Exchanger (IHX) pressure loss of 8.65%, a turbine adiabatic efficiency of 93%, and a compressor adiabatic efficiency of 88%. Results revealed that high cycle thermal efficiency of 43% can be achieved. In this cycle, three different compressors, i.e., a low-pressure compressor, a high-pressure compressor, and a bypass compressor are included. In the compressor regime, the values of properties such as specific heat and density vary sharply and nonlinearly, dependent upon the pressure and temperature. Therefore, the influences of such property changes on compressor design should be clarified. To obtain experimental data for the compressor performance in the field near the critical point, a supercritical CO 2 compressor test project was started at the Tokyo Institute of Technology on June 2007 with funding from MEXT, Japan. In this project, a small centrifugal CO 2 compressor will be fabricated and tested

IMPROVEMENT OF FLOOD REDUCTION FUNCTION OF FORESTED BASIN BY REINFORCEMENT OF EVAPORATION RATE AND GOUUND ROUGHNESS

流域治水における活用を念頭に，遮断蒸発率と地表面抵抗の増強による森林の洪水低減機能の向上について洪水ピーク流量の視点から検討した．徳島県内に位置する２つの林地（一斉植林・皆伐型施業のスギ人工林，弱間伐・択伐型施業のスギ・ヒノキを中心とする針広混交複層林）を対象に水文観測を実施し，地表面流分離直列二段タンクモデルと将来予測降雨を用いた流出シミュレーションを実施した．遮断蒸発率と地表面抵抗の洪水ピークの流量低減と遅延効果について検討した結果，対象としたスギ人工林を針広混交複層林・弱間伐に変更すると20％程度の洪水ピーク流量低減効果を得られる可能性が示唆された．Two forest operation techniques with an flood peak reduction effect were discussed using a tank-model and two small artificial forested basins where forest physiognomy was different. One operation was the way to strengthen the insulation evaporative rate by changing its physiognomy, other was the way to make forest floor vegetation and ground roughness increased. The effect when artificial cedar forest was replaced with a mixed conifer-hardwood forest was discussed. As a result, it was estimated that the flood peak flow decreased around 20% before the replacement

THE RELATION OF BETWEEN RAINFALL AND SEDIMENT DISCHARGE IN THE NISHIDANI AND THE KUMANOGAWADANI RIVER BASIN

我が国では，近年，森林の荒廃により，降水時に土砂生産・流入や崩壊危険度が増大している流域が存在するため，降水や森林荒廃が土砂生産等に影響を及ぼす程度を明確にする必要がある．本研究では，和歌山県の二級河川富田川支川の西谷川および熊野川谷川流域で，降水，河川水位，流砂量の観測を行うとともに，富田川流域に隣接する一級河川熊野川右支川の音無川流域における流出土砂推計値の検討を行った結果，降水量と流砂量の間に，雨量の閾値，土砂流出に有効な降雨強度および一次関数の関係式を見出せた．また，得られた関係式に基づく流出土砂量の予測により効率的な河川管理を行い，治水安全度の向上に資する可能性について考察を行った．Due to forest dilapidations in recent years, sediment yields from a slope and slope collapsing risk are increased. In addition to devastating sediment disasters such as happened in Kii Peninsula flooding in 2011, continuous sediment runoff following to such disasters causes riverbed aggradation and revetment damage under normal flood period,which seriously threatens safety level of flood control. Thus it is important to clarify the relationship between precipitation and sediment discharge. In this study, we analysed the relationship in the Otonashi River basin, a tributary of the Kumano River in Kii Peninsula, and tried to derive a critical hourly precipitation, that is effective to yield sediment discharge. From the analyses, the critical hourly precipitation can be found around 15mm/h or 20mm/h. Moreover, by applying the critical hourly precipitation as a cut-off value to the accumulated precipitation, a linear function between the adjusted precipitation and sediment discharge becomes clearer. These concepts were also applied to the observational results in the Nishidani and the Kumanogawadani river Basin, tributaries of the Tonda River adjacent to the Kumano River, then we showed the proposed linear function can estimate sediment discharge in accordance with a rainfall event reasonably well. Although the coefficients of the function vary from one river basin to another, the concept can be useful to estimate sediment deposition within a river section after normal flood roughly but quite easily

FLOOD CONTROL FUNCTION OF FARMLAND AS GREEN INFRASTRUCTURE USING INUNDATION ANALYSIS MODEL

本研究では,徳島県にある海部川支川善蔵川流域を対象とし,農地や湿地をグリーンインフラとし,洪水調節機能を定量的に評価する内水氾濫解析モデルを構築し,人口減少が進む当該流域における将来の土地利用の在り方を考察した.平成26年台風12号を元に,Hazen法によって確率雨量を評価し,降雨外力の違いと土地利用の違いによる洪水調節機能に与える影響を評価した.前者では,床上浸水の被害が20年確率降雨以上で顕著に増加したことから,水害リスクの高い場所と農地による洪水調節機能の発揮限界について検討した.後者では,宅地転換が進む前の過去の土地利用では,湛水量の増減の応答が早く,とりわけ集中的に浸水する領域を特定した.以上から,浸水リスクがある場所での開発を控え,社会状況に連動した優先的な退避の施策の成立が今後重要視される.In this paper, flood control function of agricultural land and wetlands were considered using an inundation analysis model, expecting to work as green infrastructure against flood. The study area is located in Zenzo River basin, a tributary of the Kaifu River, Tokushima Prefecture, where population decline is severe in recent years. Based on the rainfall by Typhoon 1412 several probable rainfalls were evaluated, and the flood control function was examined with the different rainfalls, as well as the difference of land use. The results show that, since the flood damage due to inundation above floor level remarkably increase at and over 20-year period probable rainfall, the flood control function has a limit at some stage against extreme rainfall events. On the other hand, in the past land use where more farmlands existed, temporal variation of inundation volume reduces more rapidly compared with the current land use. The results indicate it will be necessary to suppress development in high risk areas, and the past land use will be a good reference for a wise land use

FACTOR ANALYSIS OF SANDBAR DEFOMATION PROCESSES IN THE MIDDLE REACHES OF YOSHINO RIVER

The Yoshino River, Japan, is rich in water resources, but simultaneously possesses high risk of flood disaster. River improvement works to reduce damage from the floods have been conducted which attain increase of the discharge capacity. On the other hand, local sediment deposition and scouring are growing concern by the repeated floods, decreasing of sediment supply and construction of river structure. In order to resolve these problems, it is necessary to understand the effects of natural and artificial impacts on the river channel. In this paper, the channel transition processes were studied in the Middle Yoshino River using aerial photo, morphology data. Natural and artificial impacts on those processes were evaluated from sandbar deformation, fluctuation of bed elevation and volume in low-water channel. As a result, sandbar deformation by the floods and revetment works was confirmed. The floods and dam construction affected fluctuation of river channel with the sediment deposition and scouring

Differences in the gas and dust distribution in the transitional disk of a sun-like young star, PDS 70

We present ALMA 0.87 mm continuum, HCO+ J=4--3 emission line, and CO J=3--2 emission line data of the disk of material around the young, Sun-like star PDS 70. These data reveal the existence of a possible two component transitional disk system with a radial dust gap of 0."2 +/- 0."05, an azimuthal gap in the HCO+ J=4--3 moment zero map, as well as two bridge-like features in the gas data. Interestingly these features in the gas disk have no analogue in the dust disk making them of particular interest. We modeled the dust disk using the Monte Carlo radiative transfer code HOCHUNK3D (Whitney et al. 2013) using a two disk components. We find that there is a radial gap that extends from 15-60 au in all grain sizes which differs from previous work

Artificially Induced Epithelial-Mesenchymal Transition in Surgical Subjects: Its Implications in Clinical and Basic Cancer Research

BACKGROUND: Surgical samples have long been used as important subjects for cancer research. In accordance with an increase of neoadjuvant therapy, biopsy samples have recently become imperative for cancer transcriptome. On the other hand, both biopsy and surgical samples are available for expression profiling for predicting clinical outcome by adjuvant therapy; however, it is still unclear whether surgical sample expression profiles are useful for prediction via biopsy samples, because little has been done about comparative gene expression profiling between the two kinds of samples. METHODOLOGY AND FINDINGS: A total of 166 samples (77 biopsy and 89 surgical) of normal and malignant lesions of the esophagus were analyzed by microarrays. Gene expression profiles were compared between biopsy and surgical samples. Artificially induced epithelial-mesenchymal transition (aiEMT) was found in the surgical samples, and also occurred in mouse esophageal epithelial cell layers under an ischemic condition. Identification of clinically significant subgroups was thought to be disrupted by the disorder of the expression profile through this aiEMT. CONCLUSION AND SIGNIFICANCE: This study will evoke the fundamental misinterpretation including underestimation of the prognostic evaluation power of markers by overestimation of EMT IN past cancer research, and will furnish some advice for the near future as follows: 1) Understanding how long the tissues were under an ischemic condition. 2) Prevalence of biopsy samples for in vivo expression profiling with low biases on basic and clinical research. 3) Checking cancer cell contents and normal- or necrotic-tissue contamination in biopsy samples for prevalence

RNA-Binding Protein Musashi1 Modulates Glioma Cell Growth through the Post-Transcriptional Regulation of Notch and PI3 Kinase/Akt Signaling Pathways

Musashi1 (MSI1) is an RNA-binding protein that plays critical roles in nervous-system development and stem-cell self-renewal. Here, we examined its role in the progression of glioma. Short hairpin RNA (shRNA)-based MSI1-knock down (KD) in glioblastoma and medulloblastoma cells resulted in a significantly lower number of self renewing colony on day 30 (a 65% reduction), compared with non-silencing shRNA-treated control cells, indicative of an inhibitory effect of MSI1-KD on tumor cell growth and survival. Immunocytochemical staining of the MSI1-KD glioblastoma cells indicated that they ectopically expressed metaphase markers. In addition, a 2.2-fold increase in the number of MSI1-KD cells in the G2/M phase was observed. Thus, MSI1-KD caused the prolongation of mitosis and reduced the cell survival, although the expression of activated Caspase-3 was unaltered. We further showed that MSI1-KD glioblastoma cells xenografted into the brains of NOD/SCID mice formed tumors that were 96.6% smaller, as measured by a bioluminescence imaging system (BLI), than non-KD cells, and the host survival was longer (49.3±6.1 days vs. 33.6±3.6 days; P<0.01). These findings and other cell biological analyses suggested that the reduction of MSI1 in glioma cells prolonged the cell cycle by inducing the accumulation of Cyclin B1. Furthermore, MSI1-KD reduced the activities of the Notch and PI3 kinase-Akt signaling pathways, through the up-regulation of Numb and PTEN, respectively. Exposure of glioma cells to chemical inhibitors of these pathways reduced the number of spheres and living cells, as did MSI1-KD. These results suggest that MSI1 increases the growth and/or survival of certain types of glioma cells by promoting the activation of both Notch and PI3 kinase/Akt signaling

SUBARU Near-Infrared Imaging Polarimetry of Misaligned Disks Around The SR24 Hierarchical Triple System

The SR24 multi-star system hosts both circumprimary and circumsecondary disks, which are strongly misaligned from each other. The circumsecondary disk is circumbinary in nature. Interestingly, both disks are interacting, and they possibly rotate in opposite directions. To investigate the nature of this unique twin disk system, we present 0.''1 resolution near-infrared polarized intensity images of the circumstellar structures around SR24, obtained with HiCIAO mounted on the Subaru 8.2 m telescope. Both the circumprimary disk and the circumsecondary disk are resolved and have elongated features. While the position angle of the major axis and radius of the NIR polarization disk around SR24S are 55$^{\circ}$ and 137 au, respectively, those around SR24N are 110$^{\circ}$ and 34 au, respectively. With regard to overall morphology, the circumprimary disk around SR24S shows strong asymmetry, whereas the circumsecondary disk around SR24N shows relatively strong symmetry. Our NIR observations confirm the previous claim that the circumprimary and circumsecondary disks are misaligned from each other. Both the circumprimary and circumsecondary disks show similar structures in $^{12}$CO observations in terms of its size and elongation direction. This consistency is because both NIR and $^{12}$CO are tracing surface layers of the flared disks. As the radius of the polarization disk around SR24N is roughly consistent with the size of the outer Roche lobe, it is natural to interpret the polarization disk around SR24N as a circumbinary disk surrounding the SR24Nb-Nc system.Comment: 14 pages, 5 figures, accepted for publication in A