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71.
Interference of free fatty acids from the hepatopancreas of mussels with the mouse bioassay for shellfish toxins 总被引:3,自引:0,他引:3
Determination of free fatty acids (FFA) in hepatopancreas of mussel,Mytilus coruscus, contaminated by diarrhetic shellfish poisoning (DSP) toxins, was carried out by high-performance liquid chromatography-fluorometry
as their 9-anthryldiazomethane derivatives. The FFA in the hepatopancreas of mussels during May 30–June 14 were 443–666 μg/g.
A marked increase in FFA content was observed on June 20 (2197 μg/g hepatopancreas) and June 27 (6322 μg/g hepatopancreas).
The proportion of polyunsaturated fatty acids (PUFA), including 20∶4n–6, 20∶5n–3, and 22∶6n–3, in mussel FFA increased during
the experimental period. Diatoms almost completely dominated the phytoplankton community at the experimental site, suggesting
that diatoms were the origin of the PUFA accumulated in mussels. The toxicity of FFA in mussel hepatopancreas on June 27 was
sufficiently high as to interfere with the mouse bioassay by injection of an extract of shellfish, the official method for
DSP toxin analysis. 相似文献
72.
Characterization of texture and mechanical properties of heat-induced soy protein gels 总被引:8,自引:0,他引:8
Jun KangII Yasuki Matsumura Tomohiko Mori 《Journal of the American Oil Chemists' Society》1991,68(5):339-345
Heat-set gels were prepared from acid-precipitated soybean proteins at various heating temperatures (80–100°C), protein concentrations
(18–20%), and proportions of glycinin. The gels were evaluated for mechanical parameters by means of a compression-decompression
test. Gels formed at higher heating temperature and protein concentration were firm, tough and unfracturable. The elasticities
of the gels were similar at all protein concentrations and were lower when heated at higher temperature. Heating above 93°C
was necessary for formation of rigid gels. The glycinin/β-conglycinin ratio affected the texture of the gels. Three-dimensional
representation of the gels through factor analysis of instrumental data and calculation of factor scores was useful to evaluate
the texture of the gels. 相似文献
73.
74.
Naoto Aizawa Tomohiko Iwasaki Yasuaki Watanabe Tatsuro Takani 《Journal of Nuclear Science and Technology》2016,53(2):240-249
A reactivity control method for accelerator-driven system (ADS) is studied for its ability to reduce both the maximum beam current and the load on the beam window. A burnable position (BP) assembly (with gadolinium and zirconium hydride pins) is applied to the ADS core for reactivity control, and various BP assembly optimizations (such as pin arrangement, BP assembly loading position, and BP composition) are performed to minimize the burnup reactivity swing. These optimizations lead to a decreased burnup reactivity swing that is as much as 82.5% less than the swing of non-BP-loaded core; furthermore, the maximum beam current is 12.5 mA. The reactor characteristics of the optimized BP-loaded ADS core are also analyzed to investigate how the introduction of BP assembly influences the system. Safety parameters (such as the Doppler coefficient and the coolant void reactivity) worsen with the introduction of BP assembly, and the total minor actinide transmutation amount decreases 30–40 kg because of the moderated neutrons and changed fuel composition. 相似文献
75.
The aim of this study is to investigate the deposition remains of fuel droplets that impinge on a hot surface of Aluminum Alloy. The fuel droplets tested are diesel fuel (DF) and palm oil based ester that refers as a bio-diesel fuel (BDF). Temperatures of Aluminum Alloy surface and impingement interval of droplets are two parameters that were considered for various conditions of experiments. The maximum evaporation point (MEP) obtained from evaporation characteristics for each fuel was used as a reference point to decide the surface temperature of the Aluminum Alloy, where deposits of fuel were observed. The impingement interval was set at 3, 5 and 8 s with various surface temperatures of 320 °C and 370 °C. To understand the effect of heat transfer on deposition development, surface temperature of deposits was measured by using infrared thermometer. The deposition development depended on a few factors such as droplet impingement interval, hot surface temperature, type of fuel, and heat transfer of fuel deposits. BDF produced rapid development of fuel deposits comparing to DF. 相似文献
76.
Méndez-Arriaga F Otsu T Oyama T Gimenez J Esplugas S Hidaka H Serpone N 《Water research》2011,45(9):2782-2794
This article examines the oxidative disposal of Prozac® (also known as Fluoxetine, FXT) through several oxidative processes with and without UV irradiation: for example, TiO2 alone, O3 alone, and the hybrid methods comprised of O3 + H2O2 (PEROXONE process), TiO2 + O3 and TiO2 + O3 + H2O2 at the laboratory scale. Results show a strong pH dependence of the adsorption of FXT on TiO2 and the crucial role of adsorption in the whole degradation process. Photolysis of FXT is remarkable only under alkaline pH. The heterogeneous photoassisted process removes 0.11 mM FXT (initial concentration) within ca. 60 min with a concomitant 50% mineralization at pH 11 (TiO2 loading, 0.050 g L−1). The presence of H2O2 enhances the mineralization further to >70%. UV/ozonation leads to the elimination of FXT to a greater extent than does UV/TiO2: i.e., 100% elimination of FXT is achieved by UV/O3 in the first 10 min of reaction and almost 97% mineralization is attained under UV irradiation in the presence of H2O2. The hybrid configuration UV + TiO2 + O3 + H2O2 enhances removal of dissolved organic carbon (DOC) in ca. 30 min leaving, however, an important inorganic carbon (IC) content. In all cases, the presence of H2O2 improves the elimination of DOC, but not without a detrimental effect on the biodegradability of FXT owing to the low organic carbon content in the final treated effluent, together with significant levels of inorganic byproducts remaining. The photoassisted TiO2/O3 hybrid method may prove to be an efficient combination to enhance wastewater treatment of recalcitrant drug pollutants in aquatic environments. 相似文献
77.
78.
Ryo Yoshida Takamasa Sakai Osamu Tambata Tomohiko Yamaguchi 《Science and Technology of Advanced Materials》2013,14(2):95-102
We report a novel biomimetic gel that undergoes autonomous swelling-deswelling oscillations without on-off switching of external stimuli, similar to heartbeat. The mechanical oscillation of gel was produced via oscillating chemical reaction, called the Belousov-Zhabotinsky (BZ) reaction. We have prepared an ionic gel consisting of the cross-linked poly(N-isopropylacrylamide) chain to which ruthenium tris(2,2′-bipyridine), a catalyst for the BZ reaction, was covalently bonded. The BZ reaction occurring within the gel matrix generates periodic redox changes of the catalyst moiety. This chemical oscillation is converted into the mechanical oscillation of the polymer network. As a result, the gel exhibits a periodical swelling-deswelling change. The self-oscillating behaviors of the gel were investigated in detail. When the gel size is smaller than the chemical wavelength, the redox change occurs homogeneously in the gel. In this case, the volume change is isotropic and the mechanical oscillation synchronizes with chemical oscillation without a phase difference. The period and amplitude can be controlled by changing the outer substrate concentrations. In the case of rectangular shape, chemical wave propagates along the length of the gel. The wavelength and velocity depend on the reaction rate of autocatalytic process as well as the diffusivity of the activator. The dynamic behavior that locally shrunken (or swollen) parts propagate was observed, similar to the peristaltic motion of worms. By using lithography technique, a ciliary motion actuator made of the gel has been demonstrated. These self-oscillating gels may be useful in a number of important applications to intelligent biomaterials such as pulse generator or chemical pacemaker, auto-mobile actuators or micropumps with peristaltic motion, device for signal transmission, etc. 相似文献
79.
Tue NM Suzuki G Takahashi S Isobe T Trang PT Viet PH Tanabe S 《Environmental science & technology》2010,44(23):9195-9200
Few studies have investigated the human exposure to the ensemble of dioxin-related compounds (DRCs) released from uncontrolled e-waste recycling, especially from a toxic effect standpoint. This study evaluated the TCDD toxic equivalents (TEQs) in persistent extracts of settled house dust from two Vietnamese e-waste recycling sites (EWRSs) using the Dioxin-Responsive Chemically Activated LUciferase gene eXpression assay (DR-CALUX), combined with chemical analysis of PCDD/Fs, DL-PCBs, PBDD/Fs, and monobromo PCDD/Fs to determine their TEQ contribution. The CALUX-TEQ levels in house dust ranged from 370 to 1000 pg g(-1) in the EWRSs, approximately 3.5-fold higher than in the urban control site. In EWRS house dust, the concentrations of the unregulated PBDFs were 7.7-63 ng g(-1), an order of magnitude higher than those of regulated DRCs (PCDD/Fs and DL-PCBs), and PBDFs were also principal CALUX-TEQ contributors (4.2-22%), comparable to PCDD/Fs (8.1-29%). The CALUX-TEQ contribution of DRCs varied, possibly depending on thermal processing activities (higher PCDD/F-TEQs) and PBDE content in the waste (higher PBDF-TEQs). However, the percentage of unknown dioxin-like activities was high in all dust samples, indicating large contribution from unidentified DRCs and/or synergy among contaminants. Estimates of TEQ intake from dust ingestion suggest that children in the EWRSs may be adversely affected by DRCs from dust. 相似文献
80.
Toru Tonegawa Toshiyuki Ikoma Tomohiko Yoshioka Nobutaka Hanagata Junzo Tanaka 《Journal of Materials Science》2010,45(9):2419-2426
Complete carbonate substitution at A-sites (OH) of low-crystallinity hydroxyapatite with near stoichiometric composition (i.e.
Ca/P ratio of 1.65) was achieved by heating in a dry carbon dioxide flow at 1173 K for 64 h. The carbonate content was analysed
by thermogravimetry and infrared absorption spectrometry; the chemical composition was determined to be Ca9.9±0.1(PO4)6.00±0.1(CO3)0.9±0.1. The crystal structure and atomic configuration of the carbonate ion were determined by Rietveld refinement using X-ray powder
diffraction data. This analysis revealed that the space group was monoclinic Pb with a = 0.9571(1), b = 1.9085(2), c = 0.68755(3) nm and γ = 119.847(7)°. The triangular planes of the carbonate ions were oriented parallel to the c- and a-axes, though there were two independent carbonate sites with occupancy factors of 0.56(1) and 0.34(1), where the triangles
were oppositely rotated about the corresponding carbon atoms by 23° and −18°, respectively. The arrangement of the ions was
disordered, which explains the lack of a thermal phase transition below 623 K. 相似文献