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排序方式: 共有503条查询结果,搜索用时 15 毫秒
41.
Kuni Hirayama Hiroko Tanaka Kiyoko Kawana Takayuki Hiroyuki Nakazawa 《Food Additives & Contaminants》2001,18(4):357-362
A survey of plasticizers in cap-sealing resins for bottled foods has been undertaken. During 1997-1999 di-(2- ethylhexyl)phthalate (DEHP) was found in seven out of 21 samples on the Japanese domestic market and in 10 out of 61 imported samples as well as a further two samples which contained di-(2-ethylhexyl)adipate (DEHA). In the period 1993-1999, of the other plasticizers diacetyl lauroyl glycerol (DALG) was only detected in domestic samples whereas diisodecyl phthalate (DIDP) and diisononyl phthalate (DINP) were only in imported samples. It was observed overall that DEHP and DEHA were restricted to use in cap-sealing resins for bottled foods. Whilst phthalates, DEHA or DALG were detected in samples in 1993 and 1995, the investigation in 1997-1999 showed fewer samples in which these plasticizers were found. 相似文献
42.
Lack of significantly positive correlations between elemental concentrations in hair and in organs 总被引:2,自引:0,他引:2
J Yoshinaga H Imai M Nakazawa T Suzuki M Morita 《The Science of the total environment》1990,99(1-2):125-135
Elemental concentrations (Ca, Cu, Fe, Mg, P, Se and Zn) in the hair of Japanese were examined in relation to those in internal organs (cerebrum, cerebellum, heart, spleen, liver, kidney and rib). No significantly positive correlation was found between elemental concentration in hair and that in internal organ. This result indicates the restricted use of hair as a medium for the estimation of nutritional status of the essential elements examined in the present study, at least on an individual basis. The correlations between the concentrations in organs are also presented. 相似文献
43.
The microstructure of Cu interconnections fabricated by high-pressure annealing was evaluated using a field emission scanning
electron microscope/electron backscatter diffraction pattern (FE-SEM/EBSP) technique, and the results are compared with as-deposited
and normally annealed Cu films. The results show some grains extending from the bulk field to the via regions in the case
of the high-pressure annealed Cu films. The existence of via holes was also observed, in which all grains were (111) oriented.
This indicates that the high-pressure annealing process enables the Cu that in-fills the via holes to develop into favorable
microstructures, i.e., single-crystal and with (111) orientation. 相似文献
44.
Kawashima S. Endo T. Yamamoto A. Nakabayashi K. Nakazawa M. Morita K. Aoki M. 《Solid-State Circuits, IEEE Journal of》2002,37(5):592-598
In this sensing technique, pMOS charge transfer maintains the bitline level near the GND when the plate line goes high. It gives 0.5-V higher readout voltages across the cell capacitors and enables a 0.4-V higher differential amplitude in a 512-cell per bitline structure compared with the conventional high-impedance bitline sensing technique. Using the shifted bias plate line layout, only eight cells and eight sense amplifiers per cell mat are activated, and simulations show 8.06 mW at 3 V and 5 MHz, which is about the same power consumption as the conventional device 相似文献
45.
J Hayashi K Yamamoto M Sugawara Y Fujita S Nakazawa F Oguma S Tsuchida H Miyamura S Eguchi 《Canadian Metallurgical Quarterly》1992,40(10):1866-1870
Between January 1980 and August 1991, 99 patients underwent operation for mitral valve regurgitation (MR). The ages of the patients ranged from 12 to 67 years, (49.4 +/- 11.9 years), and there were 39 males and 60 females. Pathological cause of regurgitation, which was determined by intraoperative inspection and histological findings of excised leaflets, was rheumatic in 46, degenerative in 38, infective endocarditis in 9, ischemic in 4 and unknown in 2 patients. Cardiac rhythm was atrial fibrillation in 73, normal sinus rhythm in 24 and junctional rhythm in 2 patients. Our principles for valve repair were (1) excision of responsible segment and repair for prolapsed leaflet due to torn chordae, (2) shortening of elongated chordae, (3) annuloplasty, and (4) repair of perforated leaflet. Finally, 19 patients endured plastic operation, and 80 patients underwent prosthetic valve replacement. The rate of plastic procedure was 62.5% (10/16) in degenerative MR with mural chordal lesions, 42.9% (3/7) in rheumatic MR without stenosis, 22.2% (2/9) in infective endocarditis and 100% (2/2) in MR with unknown etiology. Mitral valve repair was failed both in rheumatic MR associated with stenosis (39 patients) and in ischemic MR (4 patients). A ten-year survival rate after operation was 92.2 +/- 3.1% in patients with valve replacement and 83.6 +/- 10.0% with valve repair (N.S.), and a proportion of event-free survival in patients with valve replacement was similar to valve. Late postoperative cardiac catheterization revealed decreased left ventricular volume indices and increased left ventricular end-systolic stress/volume ratio in both groups compared to preoperative values, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
46.
47.
A simplified probabilistic fault grading method is described. The concept of propagation probability is introduced in place of the sensitization probability of STAFAN, and the empirical parameters of STAFAN are eliminated. The division of input vectors into subsets is monitored by the activation or toggle rate. The accuracy of the method is examined for fault coverage estimation and for predicting the undetected faults. 相似文献
48.
The effects of nitric oxide (NO) on superoxide (O-2) generation of the NADPH oxidase in pig neutrophils were studied. NO dose-dependently suppressed O-2 generation of both neutrophil NADPH oxidase and reconstituted NADPH oxidase. Effects of NO on NADPH-binding site and the redox centers including FAD and low spin heme in cytochrome b558 and the electron transfer rates from NADPH to heme via FAD were examined under anaerobic conditions. Both reaction rates and the Km value for NADPH were unchanged by NO. Visible and EPR spectra of cytochrome b558 showed that the structure of heme was unchanged by NO, indicating that NO does not affect the redox centers of the oxidase. In reconstituted NADPH oxidase system, NO did not inhibit O-2 generation of the oxidase when added after activation. The addition of NO to the membrane component or the cytosol component inhibited the activity by 24.0 +/- 5.3 or 37.4 +/- 7.1%, respectively. The addition of NO during the activation process or to the cytosol component simultaneously with myristate inhibited the activity by 74.0 +/- 5.2 or 70.0 +/- 8.3%, respectively, suggesting that cytosol protein(s) treated with myristate becomes susceptible to NO. Peroxynitrite did not interfere with O-2 generation. 相似文献
49.
50.
Preparation and properties of CuInS2 thin film prepared from electroplated precursor 总被引:1,自引:1,他引:1
Yoshio Onuma Kenji Takeuchi Sumihiro Ichikawa Yasunari Suzuki Ryo Fukasawa Daisuke Matono Kenji Nakamura Masao Nakazawa Koji Takei 《Solar Energy》2006,80(1):132-138
Thin CuInS2 films were prepared by sulfurization of Cu/In bi-layers. First, the precursor layer was electroplated onto the treated surface of Mo-coated glass. Observation of the cross-section prepared by focused ion beam (FIB) etching revealed that the void-free film was initially formed on the top surface of the precursor layer and continued to grow until the advancing front of the film reached the Mo layer. The nucleation of voids near the bottom of the CuInS2 film followed. To determine whether the condition of the Cu/In alloy influences the CuInS2 quality we investigated the Cu/In alloy state using FIB. We found that the annealed precursor of low Cu/In ratio (1.2) has several voids in the mid position in the layer compared with Cu-rich precursor (1.6). The cross-sectional view of the Cu-rich absorber layer is uniform compared with the low copper absorber layer. Thin film solar cells were fabricated using the CuInS2 film (Cu/In ratio: 1.2) as an optical absorber layer. It was found that the optimization of a sulfurization period is important in order to improve the cell efficiency. We have not yet obtained good results with high Cu-rich absorber because of a blister problem. This blister was found before sulfurization. So, we are going to solve this blister problem before sulfurization. 相似文献