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141.
We are preparing for an ultra-high resolution X-ray spectroscopy of kaonic atoms using an X-ray spectrometer based on an array of superconducting transition-edge-sensor microcalorimeters developed by NIST. The instrument has excellent energy resolutions of 2–3 eV (FWHM) at 6 keV and a large collecting area of about 20 mm \(^2\) . This will open new door to investigate kaon-nucleus strong interaction and provide new accurate charged-kaon mass value.  相似文献   
142.
Operability of Very High Temperature Reactor (VHTR) hydrogen cogeneration systems in response to abnormal transients initiated by the hydrogen production plant is one of the important concerns from economical and safety points of views. The abnormal events in the hydrogen production plant could initiate load changes and induce temperature variations in a primary cooling system. Excessive temperature increase in the primary cooling system would cause reactor scrams since the temperature increase in the primary cooling system is restricted in order to prevent undue thermal stresses from reactor structures. Also, temperature decrease has a potential propagation path for reactor scrams by reactivity insertions as a consequence of the reactivity feedbacks. Since suspensions of reactor operation and electricity generation should be avoided even in case of abnormal events in the hydrogen production plant from an economical point of view, an establishment of a control scheme against abnormal transients of hydrogen production plant is required for plant system design.In the present study, basic controls and their integration for the GTHTR300C, a VHTR cogeneration system designed by JAEA with a direct Brayton cycle power conversion unit and thermochemical Iodine-Sulfur process hydrogen production plant (IS hydrogen production plant), against abnormal transients of IS hydrogen production plant are presented. Transient simulations for selected load change events in the IS hydrogen production plants are performed by an original system analysis code which enables to evaluate major phenomena assumed in process heat exchangers of the IS hydrogen production plant.It is shown that abnormal load change events are successfully simulated by the system analysis code developed. The results demonstrated the technical feasibility of proposed controls for continuous operation of the reactor and power conversion unit against load change events in the IS hydrogen production plant.  相似文献   
143.
In this study, a new metabolic pathway for the synthesis of poly[(R)-3-hydroxybutyrate] [P(3HB)] was constructed in a recombinant Escherichia coli strain that utilized forward and reverse reactions catalyzed by two substrate-specific enoyl-CoA hydratases, R-hydratase (PhaJ) and S-hydratase (FadB), to epimerize (S)-3HB-CoA to (R)-3HB-CoA via a crotonyl-CoA intermediate. The R-hydratase gene (phaJ(Ac)) from Aeromonas caviae was coexpressed with the PHA synthase gene (phaC(Re)) and 3-ketothiolase gene (phaA(Re)) from Ralstonia eutropha in fadR mutant E. coli strains (CAG18497 and LS5218), which had constitutive levels of the beta-oxidation multienzyme FadB(Ec). When grown on glucose as the sole carbon source, the cells accumulated P(3HB) up to an amount 6.5 wt% of the dry cell weight, whereas the control cells without phaJ(Ac) or fadR mutation accumulated significantly smaller amounts of P(3HB). These results suggest that PhaJ(Ac) and FadB(Ec) played an important role in supplying monomers for P(3HB) synthesis in the pathway. Furthermore, by using this pathway, a P(3HB)-concentration-dependent fluorescent staining screening technique was developed to rapidly identify cells that possess active R-hydratase.  相似文献   
144.
This paper proposes a novel human-robot symbiosis system named a Robotic Office Room (ROR). The understanding, recording and retrieving of telephone call behavior are successfully demonstrated as a typical example of an office work-supporting function of ROR. A unique object model is proposed, which accumulates information concerning motion of the object. This model enables the system to understand human behavior, not by monitoring the motion of the human, but by monitoring the motion of the object-typically, a telephone or pen. Since the model requires the system to pay spatial and temporal attention only to the target object and related motions, it saves computing power. Repertoires of understandable behavior can easily be expanded by simply adding new object models. The ROR is equipped with networked machines. The concept of "ubiquitous link" consisting of unique image channels and remote control channels is proposed. The image channel and the remote control channel utilize TV images and either ultrasonic waves or infrared rays, respectively. Such cooperative support of humans by networked machines is realized that when a human starts to talk on the phone, the ROR not only starts to record the image of the human's behavior, utilizing a VCR, but also turns down the volume on an audio set. The experiment proved the feasibility of the ROR as an integrated robotic system to support human office work.  相似文献   
145.
146.
Both classical and quantum version of two models of price competition in duopoly market, the one is realistic and the other is idealized, are investigated. The pure strategy Nash equilibria of the realistic model exists under stricter condition than that of the idealized one in the classical form game. This is the problem known as Edgeworth paradox in economics. In the quantum form game, however, the former converges to the latter as the measure of entanglement goes to infinity.  相似文献   
147.
The work described in this paper is a study of the high temperature corrosion reaction of iron in oils containing phosphorus compounds such as the phosphite, phosphate, thiosulphate, acid phosphate and acid phosphite, by using the hot-wire method. The neutral type esters show very little chemical reactivity towards iron in marked contrast to the very high reactivity of the acid type esters and thiophosphite. X-ray analysis revealed basic iron phosphate, 2FeFe4(PO4)(OH)5, and iron sulfide as the main reaction products for the neutral type and acid type esters and thiophosphite, respectively. The surface polishing action, peculiarly attributed to phosphorus compounds, could not be confirmed in the present work. The results from X-ray analysis seem to support the iron phosphate lubrication mechanism of phosphorus type EP additives. Some considerations are given for the correlations between the chemical reactivity, load carrying capacity and anti-wear property of oils containing phosphorus compounds. As to the lubrication characteristics of chloride, sulfide, phosphide and phosphate films, some postulations are made.  相似文献   
148.
Plaster materials made of waste gypsum or flue-gas-desulferized (FGD) gypsum with chemicals;organic and inorganic additives were studied. Glucose;citric acid and sodium bicarbonate were incorporated to retard the hydration of plaster. Saw dust (SD);coconut fibers (CCF) and tobacco waste fiber (TWF) were incorporated to improve the thermal property. Diatomaceous earth (DE);fly ash (FA) and bottom ash (BA) were incorporated to improve the mechanical and thermal properties. Citric acid;TWF;sodium bicarbonate and glucose could be used to retard the setting time of fresh FGD-plaster to approximately 25 min comparable to that of commercial plaster while the other additives did not retard the hydration. In presences of these retarding additives;needle shaped gypsum changed into lower aspect ratio particles. SD;CCF;DE;FA and BA modified gypsum crystal growth and reduced the crystal length. These changes in morphology consequently gave significant alterations of mechanical and thermal properties of the materials. The additions of organic and inorganic additives resulted in a reduction of bulk density and increases in water absorption;and similar strength compared to commercial gypsum. A good thermal insulating property was obtained from the samples with the incorporation of coconut fiber;BA and DE. In addition;these samples had a good performance in fire proof.  相似文献   
149.
Torrential rainfall in mid-July 2009 triggered numerous geodisasters such as slope failure and debris flow in Chugoku and Northern Kyushu areas of Japan. A number of slope failures and debris flows occurred in Yamaguchi and Fukuoka prefectures resulting in extensive damage to human life and infrastructure. One of the most serious geodisasters included a slope failure followed by debris flow at Sasaguri-machi and Fukuchi-machi, Fukuoka prefecture, Japan. This paper summarizes the results of geotechnical investigations on the geodisaster sites in Fukuoka prefecture. The geotechnical investigation included determining a series of grain size distributions, consistency limits and conducting direct box shear tests for collapsed soils collected at six disaster sites. The generation mechanisms of slope failure followed by debris flow were also investigated by analyzing the precipitation, topography, geology, and strength properties of the collapsed soils. Moreover, slope deformation and stability analyses were coupled with an unsaturated-saturated seepage analysis to investigate the slope failure mechanism. The main findings from the study are summarized as: The physical properties, such as the grain size distribution, the plastic limit and liquid limit of collapsed soils, are summarized and compared with the results of other failure slopes in the literature. The collapsed soil was characterized as being a well grained soil (the uniformity coefficient >50) and highly weathered (the ignition loss >5%), however, with regard to the liquid limit and plastic index, there were no remarkable findings. The original shear strength for collapsed soils with natural water content is relatively large and slope failure doesn't occur because the cohesion in the shear strength is induced by a suction force between the soil particles under unsaturated condition. However, water seepage into the soil induces a drastic decrease in the shear strength, which is mainly caused by a decrease in cohesion (losing suction) resulting from soil saturation. In addition, the drained/undrained condition in the shear process is also sensitive to shear strength. For example, both water seepage and the shear process with constant volume cause an approximate 30% reduction in shear strength for Fukuchi-machi and Sasaguri-machi soil samples. Therefore, the reduction of cohesive strength due to water seepage and the low permeability of the slope are the parameters which trigger geodisaster. Based on the results of slope deformation and a stability analyses which took the change in water pressure and cohesive strength into account, the geodisaster at Fukuchi-machi was simulated, it is reasonable to assume that the shallow failure near the top of slope occurred due to torrential precipitation of about 100 mm per hour which triggered a debris flow.  相似文献   
150.
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