ショキ シャシン アーカイブズ ノ ゲンセツ クウカン : 1851ネン ノ ミッション ・ エリオグラフィック ニ ツイテ

本稿は、写真術黎明期の19世紀中盤に、当時誕生しつつあった写真アーカイヴズが、どのような言説によって、どのように構成されていたのかを歴史社会学的に明らかにする。1851年から52年にかけて、フランスの政府機関である歴史的記念物委員会が実施した、現在では「ミッション・エリオグラフィック」として知られている写真アーカイヴズを構築する事業をとりあげ、それを当時の歴史的・社会的環境の中に位置付け直す。さらに、史料と先行研究に基づいて、当時、このミッションを構成していた言説として、製図学的言説と芸術学的言説という二つの系列を指摘し、交わることなく平行線を描くこの二つの言説の系列のあいだでこの初期写真アーカイヴズが成立していたことを示す

Formation and characterization of phthalocyanine dimer/C60 solar cells

AbstractOrganic solar cells with μ-oxo-bridged gallium phthalocyanine dimer (GaPc dimer) and fullerene were produced by an evaporation method. A device based on the GaPc dimer provided a conversion efficiency of 4.2×10–3%, which is better compared to a device based on phthalocyanine monomer. Dimerization effect was discussed with a molecular orbital calculation, and the crystalline phases of the present solar cells were investigated by X-ray diffraction. Further improvement of the efficiency was discussed on the basis of the experimental results

Magnetization anomaly of Nb3Al strands and instability of Nb3Al Rutherford cables

Using a Cu stabilized Nb{sub 3}Al strand with Nb matrix, a 30 meter long Nb{sub 3}Al Rutherford cable was made by a collaboration of Fermilab and NIMS. Recently the strand and cable were tested. In both cases instability was observed at around 1.5 Tesla. The magnetization of this Nb{sub 3}Al strand was measured first using a balanced coil magnetometer at 4.2 K. Strands showed an anomalously large magnetization behavior around at 1.6 T, which is much higher than the usual B{sub c2} {approx} 0.5 Tesla (4.2 K) of Nb matrix. This result is compared with the magnetization data of short strand samples using a SQUID magnetometer, in which a flux-jump signal was observed at 0.5 Tesla, but not at higher field. As a possible explanation for this magnetization anomaly, the interfilament coupling through the thin Nb films in the strands is suggested. The instability problem observed in low field tests of the Nb{sub 3}Al Rutherford cables is attributed to this effect

Phase transition in traffic jam experiment on a circuit

The emergence of a traffic jam is considered to be a dynamical phase transition in a physics point of view; traffic flow becomes unstable and changes phase into a traffic jam when the car density exceeds a critical value. In order to verify this view, we have been performing a series of circuit experiments. In our previous work (2008 New J. Phys. 10 033001), we demonstrated that a traffic jam emerges even in the absence of bottlenecks at a certain high density. In this study, we performed a larger indoor circuit experiment in the Nagoya Dome in which the positions of cars were observed using a high-resolution laser scanner. Over a series of sessions at various values of density, we found that jammed flow occurred at high densities, whereas free flow was conserved at low densities. We also found indications of metastability at an intermediate density. The critical density is estimated by analyzing the fluctuations in speed and the density-flow relation. The value of this critical density is consistent with that observed on real expressways. This experiment provides strong support for physical interpretations of the emergence of traffic jams as a dynamical phase transition.Tadaki S.I., Kikuchi M., Fukui M., et al. Phase transition in traffic jam experiment on a circuit. New Journal of Physics 15, 103034 (2013); https://doi.org/10.1088/1367-2630/15/10/103034