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101.
Yukari Tsumura Susumu Ishimitsu Isao Saito Hiroshi Sakai Yukari Kobayashi Yasuhide Tonogai 《Food Additives & Contaminants》2001,18(5):449-460
Plasticizers in duplicate diet samples obtained over 1 week were analysed in order to estimate daily intake. The phthalate esters were as follows: diethyl, dipropyl, dibutyl, dipentyl, dihexyl, butylbenzyl, dicyclohexyl, di(2-ethylhexyl), dioctyl, diisooctyl (mixture of isomers) and diisononyl (mixture). Di(2-ethylhexyl) adipate was also determined. Homogenized samples of composite meals were extracted with acetonitrile, lipids were removed by extraction into n-hexane and the acetonitrile layer was cleaned using FlorisilR and R Bondesil PSA dual layer column. Phthalates were determined by GC/MS (SIM). Phthalate recovery from the fortified food mixture by this method was 62.5-140.8%. Quality assurance as assessed by three laboratories indicated coefficient of variance in the levels of detected phthalates in same lot samples as below 10%. Detection limits were 0.1-23ng/g for each phthalate. One-week duplicate diet samples provided by three hospitals in three remote prefectures of Japan were analysed as individual meals. In all 63 samples, DEHP was present at the highest level among all phthalates in the range 10-4400ng/g. The intake of plasticizers estimated from all samples was 519 µ g DEHP/day, 86 µ g DEHA/day, 65 µ g DINP/day, and 4.7 µ g BBP/day. Calculated DEHP in 2-day samples out of 21 days exceeded EU TDI for a person of 50kg body weight (1850 µ g per day). Disposable PVC gloves used during the preparation of meals were suspected as the source of the high DEHP content. One-day intake of the other phthalates and DEHA was below 7% of TDI in all cases. High concentrations of DEHP (5990ng/g) was found in baby food used in quality assurance work. The source of contamination was the PVC-tube used during production and was effectively reduced by replacing the tube by one made of stainless steel. 相似文献
102.
Simple formulas are proposed for predicting the Munsell value of colors with the same tone (the same values for whiteness‐blackness, perceived lightness, and chroma irrespective of hue). The formulas can be used for any tone. In other words, the method can determine the Munsell value with the same perceived lightness at any specified chroma irrespective of hue. The chromatic strength (CS) function is only used for the derivations. The formulas are very simple, and can be used not only in the colorimetry but also in the color design field. The concept described in this study is that a common CS function can be used for transforming each of the three color attributes (hue, lightness, and chroma) from their uniform color space metric to their corresponding color appearance space attribute. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2011 相似文献
103.
Isao Kagomiya Shinji Matsumoto Ken-ichi Kakimoto Hitoshi Ohsato Hiroshi Sakai Yukinori Maeda 《Journal of the European Ceramic Society》2013,33(5):985-990
We investigated annealing effects of La1?xSrxMnO3 (x = 0–0.6) on electrical resistivity and the temperature coefficient of resistivity (TCR). The annealed samples’ resistivity was lower than those of non-annealed samples. For example, annealing changed the resistivity of x = 0.3 at 25 °C from 4.50 × 10?5 to 3.71 × 10?5 Ω m. Remarkable difference in TCR was observed after annealing, for x = 0.3, 0.45, and 0.5. For x = 0.3, the TCR after annealing was 4000 ppm/°C, which was 1250 ppm/°C greater than that before annealing. We investigated (1) crystal phase, (2) Mn average valence, (3) Mott insulator–metal transition temperature, and (4) microstructure. The microstructure was remarkably varied for annealed x = 0.3 and 0.5. The average grain size of the x = 0.3 increased from 1.60 up to 2.38 μm. Results show that annealing affects resistivity and TCR because of grain growth during annealing. 相似文献
104.
I Ikai Y Yamamoto N Ozaki Y Sakai Y Shimahara Y Yamaoka 《Canadian Metallurgical Quarterly》1997,98(8):691-696
Approximately 80% of hepatocellular carcinoma (HCC) patients in Japan have associated liver cirrhosis, which increases the difficulty of surgical treatment. Liver dysfunction associated with liver cirrhosis is one of the most important predictive prognostic factors for HCC patients. Percutaneous ethanol injection therapy (PEIT) is useful for patients with small HCC or with poor hepatic functional reserve. Transcatheter arterial chemoembolization (TACE) is also useful both for patients with unresectable HCC and patients with multiple intrahepatic recurrence. Liver resection, however, lead to better outcome than other treatments when liver function is maintained after surgery. To determine operative procedures, it is important to evaluate the exact function of remnant liver, based on the preoperative liver function test and the evaluation of tumor character. For advanced HCC patients with vascular invasion, non-surgical treatments such as PEIT or TACE are not indicated, and surgical intervention can be an effective modality to improve their survival. Improvements of surgical technique and perioperative management have decreased fatal complications at a major liver resection and allowed us to carry out liver resection on patients with advanced HCC. 相似文献
105.
A frequency-stabilized distributed-feedback (DFB) laser module using the vibrational-rotational absorption of acetylene molecules is discussed. The size of this device is about 4.5 cm long, 2 cm wide, and 2 cm high. Frequency stability to within 0.5 MHz peak/peak fluctuation was achieved at the 1.53159 μm wavelength 相似文献
106.
Toshiro Sakai Yasuhiro Tanaka Tadashi Fukao Tatsuo Takada Takashi Maeno 《Electrical Engineering in Japan》2008,162(2):10-19
Most of the breakdowns in an electric power system are caused by lightning to the tower used for high‐voltage transmission wires. To avoid accidents due to lightning, it would be desirable to develop a measurement system for the spatial electric field distribution around the tower. We have developed a new system that can measure the electric field around the steel tower for electric power transmission by using an optical electric sensor. In conventional methods, the sensor is generally illuminated by light transmitted by optical fibers. On the other hand, the new measurement system illuminates the Pockels sensor directly by using a laser to measure the far electric field. Furthermore, our newly proposed feedback system makes it possible to measure the spatial electric field without concern for the change of Pockels sensor's operation point influenced by temperature change. This system is applicable as a remote sensing system to monitor the spatial electric field around a high‐voltage transmission line. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(2): 10–19, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20552 相似文献
107.
108.
Measurements have been made of complex impedance and sorbed water of polysodium phosphate. The resistance and its activation
energy decreases with an increase in the amount of sorbed water. The amount of sorbed water is strongly affected by the Na2O/P2O5 mol ratio. The humidity dependence of the activation energy and the resistance is lowered by decreasing the average chain
length of polysodium phosphate. This results in an increase in the amount of sorbed water. Especially, in low humidity conditions,
the decrease in the resistance and the activation energy are achieved by increasing the concentration of the strongly acidic
PO-H group. These improvements can not be achieved by increasing the Na2O/P2O5 mol ratio. In a humid atmosphere, the resistance of the film, in which the Na2O/P2O5 mol ratio is less than 0.8, is inversely proportional to the concentration of the strongly acidic PO-H group. 相似文献
109.
Nobukata H. Takagi S. Hiraga K. Ohgishi T. Miyashita M. Kamimura K. Hiramatsu S. Sakai K. Ishida T. Arakawa H. Itoh M. Naiki I. Noda M. 《Solid-State Circuits, IEEE Journal of》2000,35(5):682-690
We report a fast-programming, compact sense and latch (SL) circuit to realize an eight-level NAND flash memory. Fast programming is achieved by supplying optimized voltage and pulsewidth to the bit lines, according to the programming data. As a result, all data programming is completed almost simultaneously, and 0.67-MB/s program throughput, which is 1.7 times faster than conventional program throughput, is achieved. The compact layout of the SL circuit is made possible by four 3-bit latches sharing one unit of the read/verify control circuit. Using these techniques, we fabricated a 144-Mb, eight-level NAND flash memory using a 0.35-μm CMOS process, resulting in a 104.2-mm2 die size and a 1.05-μm2 effective cell size 相似文献
110.
Takeshita T. Shibata Y. Ito T. Sakai Y. Okamoto M. Tohmori Y. 《Quantum Electronics, IEEE Journal of》2001,37(12):1636-1642
A laser with a reverse-V-shape layer exhibits a circular beam spot and low threshold current. The beam aspect ratio of the reverse-V-shape laser is clarified to be insensitive to reverse-V-shape width. The reverse-V-shape layer consists of a strained active layer and a passive guide layer, which leads to a low threshold current. The reverse-V-shape laser is attractive as an optical source for optical-communication and information systems 相似文献