Turbulent jet interaction with a long rise-time pressure signature

A sonic boom signature with a long rise time has the ability to reduce the sonic boom, but it does not necessarily minimize the sonic boom at the ground level because of the real atmospheric turbulence. In this study, an effect of the turbulence on a long rise-time pressure signature was experimentally investigated in a ballistic range facility. To compare the effects of the turbulence on the long and short rise-time pressure signatures, a cone-cylinder projectile that simultaneously produces these pressure signatures was designed. The pressure waves interacted with a turbulent field generated by a circular nozzle. The turbulence effects were evaluated using flow diagnostic techniques: high-speed schlieren photography, a point-diffraction interferometer, and a pressure measurement. In spite of the fact that the long and short rise-time pressure signatures simultaneously travel through the turbulent field, the turbulence effects do not give the same contribution to these overpressures. Regarding the long rise-time pressure signature, the overpressure fluctuation due to the turbulence interaction is almost uniform, and a standard deviation 1.5 times greater than that of the no-turbulence case is observed. By contrast, a short rise-time pressure signature which passed through the same turbulent field is strongly affected by the turbulence. A standard deviation increases by a factor of 14 because of the turbulence interaction. Additionally, there is a non-correlation between the overpressure fluctuations of the long and short rise-time pressure signatures. These results deduce that the length of the rise time is important to the turbulence effects such as the shock focusing/diffracting

A Comparison of Fermentation Kinetics in the Rumen of Grazing Sheep on a Dwarf Bamboo Pasture and a Grass Pasture

Native grasses grown as forest understory are important forage resources for grazing ruminants and in agroforestry. Dwarf bamboo is one such typical grass and has traditionally been used in Japan. The name “dwarf bamboo” refers to a group of native grasses from certain genera (e.g., Sasa spp. and Pleioblastus spp.). These grasses are generally rhizomatous, perennial, and semi-woody (Usui, 1961). The results of an earlier study suggested that the in sacco ruminal degradation of the dwarf bamboo was inferior to that of a common tropical grass (Yayota et al. 2009), and cattle grazing on a forest pasture dominated by a dwarf bamboo could not satisfy their energy requirement in fall regardless of forage availability (Nakano et al. 2007). However, little information is available about the fermentation kinetics of dwarf bamboo or of many other native forage plants in the rumen. Understanding fermentation kinetics will be useful to improve the utilization of this grass and to plan supple-mental feeding strategies. The objective of this study was to clarify the fermentation kinetics of a dwarf bamboo (Pleioblastus argenteostriatus f. glaber) in the rumen relative to the fermentation kinetics of a common grass

Ruminal Disappearance and Passage Rates in Fresh Nezasa Dwarf Bamboo Growing in Japanese Native Pasture

Nezasa dwarf bamboo (Pleioblastus chino makino) is one of major native forages for grazing in Japan. However its nutritional utilisation in the rumen has been little studied. The object of this research was to measure ruminal disappearance and passage rates in fresh Nezasa dwarf bamboo compared with improved grass

On Effective Locations of Catalytic Active Sites in Phase Boundary Catalysts

Zeolite loaded with alkylsilane-covered titanium oxide was found to be more effective than its nonporous silica counterpart as phase-boundary catalyst (PBC) to promote epoxidation of alkenes with aqueous hydrogen peroxide. It was demonstrated that the phase-boundary catalyst system required neither stirring to make an emulsion, nor addition of a cosolvent to make a homogeneous solution to drive the reaction. However, some basic facts about them remain unclear, such as the question as to where an effective location of the active sites of PBC resides: is it on the external surface of the catalysts, or in their pores? In order to elucidate this problem, TS-1, HZSM-5 and zeolite loaded with alkylsilane"“covered sulfonic acid in which the location of the active sites is mainly inside the pore system, were chosen as model catalysts. Catalytic activities of the catalysts TS-1 and HZSM-5 were examined after modification with n-octadecyltrichlorosilane (ODS). Their activities were compared with zeolite loaded with alkysilane-covered titanium oxide particles, in which the active sites are on the external surface in reactions of 1-octene with aqueous H2O2 and cyclohexene with water as model reactions. The study suggests that the location of the active sites on the external surface plays an important role in the phenomenon of phase-boundary catalysis

動物の地震予知能力に関する研究 : イヌによる地震予知の可能性

1995年1月17日に阪神・淡路大震災が発生した。神戸市など震源地周辺で飼育されていたイヌのうち約20%が地震発生前に異常行動を示したことが地震発生後の調査によって報告された。本研究では，イヌの示した異常行動の原因は地震前に発生する電磁波を感知したためではないかとの仮説のもと，人工的に発生させた電磁波をイヌに照射し，照射後の行動および神経内分泌学的な変化を観察した。There were lots of reports concerning the unusual behavior of animals before the Great Hanshin Earthquake on January 17, 1995, although those cases were reported after the earthquake. About 20 % of dogs which were kept at Kobe and its neighboring areas showed unusual behavior: dogs that seldom barked howled; dogs that were always gentle bit their owners suddenly; dogs showed no appetite; dogs were severely frightened; dogs were eager to go out their homes, etc. We hypothesize that those dogs sensed extraordinary changes in their unusual environment, for example, an abnormal production of electromagnetic wave (EMW). In this study we exposed the unusual EMW, which was observed before the earthquake, to dogs, and examined the changes in their behavior and neuroendocrine parameters. Finally we have found dogs having the ability to sense the EMW observed before and at the Great Hanshin Earthquake

Optimization of Boundary Conditions for a Global MHD Simulation Model by Using Data Assimilation

第3回極域科学シンポジウム/第36回極域宙空圏シンポジウム 11月26日（月）、27日（火） 国立極地研究所 2階ラウン

Holocene paleolimnological studies of lakes in the Soya Kaigan of Antarctica inferred from the analyses of lake sediment cores

第3回極域科学シンポジウム　横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月26日（月）、27日（火） ２階ラウン