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71.
Haruhiko Okumura Masahiro Baba Kazuki Taira Makiko Okumura 《Journal of the Society for Information Display》2006,14(10):941-948
Abstract— In this paper, the development of an advanced level‐adaptive overdrive (A‐LAO) method applicable to a full‐HD LC projector with 1.84 Mpixels, which reduced the gray‐level response time to less than 16 msec, is introduced. In addition, it is shown that a response of less than 8 msec can be achieved by combining the A‐LAO method with a frame interpolation method (120‐Hz refresh). A new motion‐picture evaluation method using frequency‐domain analysis, in other words, perceived bandwidth instead of the conventional time‐domain‐analysis response time evaluation, is reported. 相似文献
72.
Masao Yamamoto Katsunori Yamaura Makiko Ishiwatari Maki Shimada Sayaka Kado Hiroko Seki Norimoto Shimada Koichi Ueno 《Journal of food science》2013,78(3):S477-S483
In recent years, many anthocyanin‐containing dietary supplements of various dosages and formulations have been sold through advertising their large number of beneficial effects. On the other hand, there is an increased risk of distributing deteriorated supplements to consumers due to lax regulations, because in Japan these supplements are classified as food. Spectrophotometric methods are commonly used to control the quality of supplements. However, these methods have limitations with regard to assessing deterioration. In this study, we evaluated a new index for detection of deteriorated products. The stability of 3 formulations and the quality of 20 supplements were investigated by ultra‐high performance liquid chromatography, which is superior to spectrophotometry for identifying and quantifying individual anthocyanins. The stability was not only affected by storage temperature but also by formulation. We defined “Degradation Index” (DI) as an indicator of the deterioration of supplements. Of 20 supplements investigated, the DI of 5 supplements was more than 3‐fold the value of Bilberon‐25, and the worst one was 12.7‐fold. These results suggest that DI could be a useful quality control index for detecting deteriorated supplements. 相似文献
73.
The electrochemical performances of proton-conducting SOFCs with the perovskite-type oxide cathodes were investigated at low temperature of 773 K. Among the perovskite-type oxides used in the present study, La0.7Sr0.3FeO3 (LSF) cathode exhibited the lowest overpotential at 773 K. The power density of the SOFC was dependent on the particle size of LSF cathode. The decrease in the particle size resulted in the decrease in overpotential. The power density of the cell with LSF cathode was also dependent on the thickness of LSF cathode; in the present condition, the LSF cathode with 13-μm thickness showed the best electrochemical performance at 773 K. 相似文献
74.
Makiko Nagamori Toshitaka Funazukuri 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):229-233
Starch was converted into glucose by hydrolysis with water under hydrothermal conditions at 453–513 K in a small batch reactor. The major product was glucose; oligomers having various degrees of polymerization, maltose, fructose, 5‐hydroxymethylfurfural and furfural were also produced. The maximum yield of glucose obtained was 630 g kg?1 on the carbon basis at 473 K and 30 min, where the quantity of carbon unrecovered was about 50 g kg?1, and the production of char and gaseous products was negligible. Copyright © 2004 Society of Chemical Industry 相似文献
75.
We examined the attachment of enterohemorrhagic Escherichia coli O157:H7 to abiotic surfaces of cooking utensils. When the cell suspension in 0.85% NaCl (about 100 cells/mL, 10 mL) was contacted with various abiotic surfaces (square pieces, 25 cm2) at 25 °C for 20 min, the number of attached cells varied depending on the types of abiotic materials. The pathogen well attached to stainless steel (about 50 cells/25 cm2), pure titanium (35 to 45 cells/25 cm2), and glass (about 20 cells/25 cm2), but little attached to aluminum foil and plastics, irrespective of strains used. Fewer cells (below 10 cells/25 cm2) attached to stainless steel, pure titanium, and glass surfaces conditioned with aseptically sliced beef (sirloin) and autoclaved beef tallow at 25 °C for 20 min, but bovine serum albumin did not reduce the number of attached cells. The cells grown at 15 °C to the stationary phase (OD660 = about 2.8) less attached to the abiotic surfaces than those grown at 25 °C and 37 °C. When we pretreated the cells at 37 °C for 2 h with 50 μM N-hexanoyl-L-homoserine lactone (HHL), the number of cells attached to stainless steel was reduced by 70%. The number of cells attached to cooking utensils seemed to change depending on types of abiotic materials, adhesion of beef tallow to abiotic surfaces, growth temperature of the pathogen, and HHL-producing bacteria. 相似文献
76.
A selective detection method for biogenic amines present in highly complex matrixes was devised by employing both electrokinetic injection and on-column-derivatization capillary electrochromatographic methods. The on-column derivatization capillary electrochromatography system was evaluated by use of a capillary column (total length of 45 cm, effective length of 25 cm) fabricated using a 100-mcirom (i.d.) fused-silica capillary tube packed with 5-microm (i.d.) ODS particles that were tolerant of an alkaline environment. The column was filled with a run buffer consisting of a derivatization reagent, o-phthalaldehyde/2-mercaptoethanol, in a mixture of borate buffer (pH 10). After electrokinetic injection of a mixture of five biogenic amines (histamine, serotonin, tyramine, putrescine, cadaverine) as a test sample, the free amines entered into the anodic site of the capillary column and started to travel along the column, during which time the analytes reacted with the derivatization reagent, separated out, and were detected with an absorbance at 340 nm when high voltage was applied to the column. When this system was applied to a mixture containing 5 biogenic amines and 17 amino acids, the 5 biogenic amines plus arginine selectively entered into the capillary with the electrokinetic injection and were observed on the electrochromatogram, but none of the amino acids lacking arginine were detected. The designated method was also tested for its ability to determine the presence of biogenic amines in the crude extracts obtained from two types of aged fish. 相似文献
77.
In this paper, we consider a control problem for nonholonomic multi-agent systems in which agents and obstacles operate within a circular-shaped work area. We assume that agents only have limited sensing and communication ranges. We propose a novel control scheme using potential functions that drives agents from the initial to the goal configuration while avoiding collision with other agents, obstacles, and the boundary of the work area. The control scheme employs an avoidance strategy that ensures that the agents are never trapped at local minima that are typically encountered with most potential function-based approaches. A numerical simulation is presented to demonstrate the validity and effectiveness of the proposed control scheme. 相似文献
78.
Tomohiro Iwasaki Munetake SatohMasakazu Okui Makiko KobayashiTooru Sugawara Ryuta Tsuchiya 《Powder Technology》2003,131(1):40-47
The apparent viscosity of a wet powder consisting of porous silica particles and a viscous liquid was evaluated by means of a newly developed powder rheometer in which a rotating conical rotor with grooves on the surface intrudes semi-statically into the powder bed. Using this rheometer, the relationship between the shear torque and the depth of intrusion, i.e., the torque characteristic curve, was measured under various conditions. The shear force acting on a contact point between the particles was estimated from the torque characteristic curve. Above the critical liquid amount in which the pores of the particles were filled with the liquid, the shear force increased with an increase in the thickness of the liquid film formed on the particle surface regardless of the pore volume. From the change of shear force with the physical properties of the liquid, it was clear that the shear force is closely related to the liquid bridge force acting on the contact points between the particles. The apparent viscosity coefficient of the wet powder was determined from the shear rate dependence of the shear force. At the relatively high liquid amounts corresponding to funicular and capillary states, the apparent viscosity coefficient increased sharply with the thickness of the liquid film since the viscosity of the liquid strongly affected the shear flow of the wet powder. Subtle changes of the apparent viscosity due to the liquid amount and the physical properties of the liquid can be sensitively detected by using the rotary-intrusion method. 相似文献
79.
The initiator-fragment incorporation radical polymerization was extended to a copolymerization system of a trivinyl monomer. The copolymerization of trimethylolpropane trimethacrylate (TMPTM) as a trivinyl monomer with α-methylstyrene (MSt) was examined at 70 and 80 °C in toluene using dimethyl 2,2′-azobisisobutyrate (MAIB) of high concentrations as initiator. When the concentrations of TMPTM, MSt and MAIB were 0.30, 0.60 and 0.50 mol/l, the copolymerization proceeded homogeneously without gelation at 80 °C to yield soluble hyperbranched copolymer in a yield of 65%. The copolymer formed for 8 h consisted of 37 mol% of the TMPTM unit, 42 mol% of the MSt unit and 21 mol% of the methoxycarbonylpropyl group as initiator-fragment, where 22% of the vinyl groups of the incorporated TMPTM units remained unreacted. The copolymer showed an upper critical solution temperature (32 °C on cooling) in a tetrahydrofuran(THF)-water [44:10 (wt/wt)]. Reflecting the hyperbranched structure, the viscosity of a copolymer solution in toluene was very low. The porous film was prepared directly by casting a THF solution of the hyperbranched copolymer on a cover glass. The copolymer molecules are radially arranged on the surface layer of the spherical pores as showed by polarized optical microscope imaging. 相似文献
80.
Climate change and trace gases 总被引:2,自引:0,他引:2
Hansen J Sato M Kharecha P Russell G Lea DW Siddall M 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2007,365(1856):1925-1954
Palaeoclimate data show that the Earth's climate is remarkably sensitive to global forcings. Positive feedbacks predominate. This allows the entire planet to be whipsawed between climate states. One feedback, the 'albedo flip' property of ice/water, provides a powerful trigger mechanism. A climate forcing that 'flips' the albedo of a sufficient portion of an ice sheet can spark a cataclysm. Inertia of ice sheet and ocean provides only moderate delay to ice sheet disintegration and a burst of added global warming. Recent greenhouse gas (GHG) emissions place the Earth perilously close to dramatic climate change that could run out of our control, with great dangers for humans and other creatures. Carbon dioxide (CO2) is the largest human-made climate forcing, but other trace constituents are also important. Only intense simultaneous efforts to slow CO2 emissions and reduce non-CO2 forcings can keep climate within or near the range of the past million years. The most important of the non-CO2 forcings is methane (CH4), as it causes the second largest human-made GHG climate forcing and is the principal cause of increased tropospheric ozone (O3), which is the third largest GHG forcing. Nitrous oxide (N2O) should also be a focus of climate mitigation efforts. Black carbon ('black soot') has a high global warming potential (approx. 2000, 500 and 200 for 20, 100 and 500 years, respectively) and deserves greater attention. Some forcings are especially effective at high latitudes, so concerted efforts to reduce their emissions could preserve Arctic ice, while also having major benefits for human health, agricultural productivity and the global environment. 相似文献