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71.
A cell immobilization technique to prevent cell leakage from the matrix in a very common system, alginate-Saccharomyces cerevisiae, was investigated. A double coating of immobilized cell beads prevented leakage very well in flask fermentation even when shaking was applied. The suitable concentrations of sodium alginate were 5, 5 and 3 wt% for the core, internal coating and external coating, respectively. The suitable concentration of calcium chloride was 1 wt% for all cases. Fermentation using a fixed bed reactor containing the immobilized cells was carried out successfully for 25 d.  相似文献   
72.
A new calorimeter for measurements of the heat capacity and magnetocaloric effect of small samples in pulsed magnetic fields is discussed for the exploration of thermal and thermodynamic properties at temperatures down to 2 K. We tested the method up to μ(0)H=50?T, but it could be extended to higher fields. For these measurements we used carefully calibrated bare-chip Cernox(?) and RuO(2) thermometers, and we present a comparison of their performances. The monotonic temperature and magnetic field dependences of the magnetoresistance of RuO(2) allow thermometry with a precision as good as ±4 mK at T=2?K. To test the performance of our calorimeter, heat capacity and magnetocaloric effect for the spin-dimer compound Sr(3)Cr(2)O(8) and the triangular lattice antiferromagnet RbFe(MoO(4))(2) are presented.  相似文献   
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Abstract— A multi‐view depth‐fused 3‐D (DFD) display that provides smooth motion parallax for wide viewing angles is proposed. A conventional DFD display consists of a stack of two transparent emitting screens. It can produce motion parallax for small changes in observation angle, but its viewing zone is rather narrow due to the split images it provides in inclined views. On the other hand, even though multi‐view 3‐D displays have a wide viewing angle, motion parallax in them is discrete, depending on the number of views they show. By applying a stacked structure to multi‐view 3‐D displays, a wide‐viewing‐angle 3‐D display with smooth motion parallax was fabricated. Experimental results confirmed the viewing‐zone connection of DFD displays while the calculated results show the feasibility of stacked multi‐view displays.  相似文献   
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76.
A room-cooling system of 2 kW capacity fueled by wood pellets was designed, built and tested. The system was demonstrated during summer at the Yakushima Field Station of Kagoshima University, Japan. It contained a pellet feeder, a pellet burner, a heat exchanger, a lithium bromide–water absorption heat pump and a control unit. The volume of the test room was 36.9 m3 and ambient temperature 30 °C. The airflow temperature from the room unit was decreased to 16 °C by the system, and the room temperature could be successfully controlled to 24 °C steady state. Room heating in winter was also demonstrated. Since the air was heat exchanged, the overall energy efficiency of the cooling system was low at about 19%. However, the calculation based on the heat flow showed that the efficiency could be enhanced to about 75% by direct heating of the regenerator by the flue gas.  相似文献   
77.
We describe two cases of malignant lymphoma presenting as inflammatory nodules of the leg and mimicking panniculitis clinically. In both cases the skin biopsies showed prominent involvement of the subcutaneous tissue by lymphoma cells. In addition, lymphoma cells invaded blood vessels in the dermis or the subcutaneous tissue. One case was characterized by predominantly extravascular and intravascular location of the lymphoma cells, and the other case by the predominantly extravascular and intramural location of lymphoma cells. These histological findings were compatible with those of angiocentric T-cell lymphoma but with some unusual features. Angiocentric T-cell lymphoma of the skin should be listed in the group of diseases which present as inflammatory nodules of the leg.  相似文献   
78.
The critical behavior of micellar solutions of triethylene glycol monon-hexylether in water has been investigated in view of the issue of critical-point universality for such systems close to their critical mixing point. The values of the critical exponents obtained in this work are in excellent agreement with the theoretical ones for three-dimensional Ising-like systems. The dynamical critical behavior is also discussed.Paper presented at the Tenth Symposium on Thermophysical Properties, June 20–23, 1988, Gaithersburg, Maryland, U.S.A.  相似文献   
79.
Low-pressure organometallic chemical vapour deposition (OMCVD) and dip-coating of VO2 films using vanadyl tri(isobutoxide) as the starting material were investigated. In OMCVD, discontinuous VO2 films, which were composed of fine needle crystals, formed under very limited conditions, around 600° C with a flow rate of oxygen gas of 0.2 to 0.5 cm3 sec–1. However, very uniform and tightly packed VO2 films were grown by deposition at 300 to 700° C in the absence of oxygen gas and subsequent annealing in nitrogen at 500° C for 2 h. The films exhibited a sharp semiconductor to metal transition at 60 to 70° C, accompanied by a change in the resistivity by four to five orders of magnitude. In dip-coating with two-step heat-treatments (300° C for 1 h in nitrogen and subsequently 500° C for 2 h in nitrogen), of the gel films formed from VO(O-i-Bu)3-H2O-i-PrOH system, uniform (0 1 1) oriented VO2 films were formed. A transition in the electrical conductivity by two to two and a half orders of the magnitude was found to occur around 60° C. Before and after the transition, no distinct variation in the XRD pattern was observed.  相似文献   
80.
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