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311.
Bioconcentration factors (BCF) in carp (Cyprinus carpio L.) and partition coefficients between n-octanol and water (Pow) were measured for triphenyltin chloride (Ph3SnCl), diphenyltin dichtende (Ph2SnCl2) and monophenyltin trichloride (PhSnCl3). Log Pow was 2.11 for Ph3SnCl, 1.43 for Ph2SnCl2 and 1.73 for PhSnCl3. The order of log BCF was kidney > liver > muscle gallbladder for Ph3SnCl, liver > kidney > gallbladder > muscle for Ph2SnCl2 and kidney liver > gallbladder > muscle for PhSnCl3. Further, metabolism in carp was studied on Ph3SnCl. Ph2Sn2+ and PhSn3+, the metabolites of Ph3SnCl were detected in muscle and viscera. The ratio of Ph3SnCl, Ph2Sn2+ (Ph2SnCl2) and PhSn3+ (PhSnCl3) concentrations by metabolism in each part of carp corresponded to that of BCF by carp for the same phenyltin chlorides. 相似文献
312.
Column and row electrodes on two different glass substrates were orthogonally arranged in order to assemble an addressable microelectrode device for the purpose of comprehensive electrochemical detection. Amperometric signal at the individual crossing point of the column and row electrodes was detected separately on the basis of redox cycling of localized electroactive species occurring between the electrodes. The addressable microelectrode device was simple and could be easily assembled; however, it comprised as many as 10 x 10 addressable detection points on a single chip. The basic electrochemical performance of the device was investigated by using the ferricyanide/ferrocyanide redox couple. Electrochemical responses at 100 individual points could be collected within 22 s. The present device was successfully used for imaging the spots of alkaline phosphatase on the array substrate. The results indicate that the device can be applied to comprehensive and high-throughput detection and imaging of biochemical species. 相似文献
313.
Generalized block-lifting factorization of M-channel (M > 2) biorthogonal filter banks (BOFBs) for lossy-to-lossless image coding is presented in this paper. Since the proposed block-lifting structure is more general than the conventional lifting factorizations and does NOT require many restrictions such as paraunitary, number of channels, and McMillan degree in each building block unlike the conventional lifting factorizations, its coding gain is higher than that of the previous methods. Several proposed BOFBs are designed and applied to image coding. Comparing the results with conventional lossy-to-lossless image coding structures, including the 5/3- and 9/7-tap discrete wavelet transforms in JPEG 2000 and a 4 × 8 hierarchical lapped biorthogonal transform in JPEG XR, the proposed BOFBs achieve better result in both objective measure and perceptual visual quality for the images with a lot of high-frequency components. 相似文献
314.
Ken Hasegawa Masakazu Aoki Taizo Yamawaki Satoshi Tanaka 《Analog Integrated Circuits and Signal Processing》2012,72(3):605-613
We propose a statistical MOSFET model using the ??-power equation for the I D ?CV GS curves of a transistor to make it easier to deal with transistor variations using hand calculations. We evaluated the impact of the transistor variation (mismatch) on the harmonic distortion (HD) in a differential amplifier using the statistical ??-power model along with a sensitivity simulation using SPICE. We found that the driver transistor variation majorly impacted on the 2nd HD in the differential gain, which was approximately proportional to the transistor current mismatch, whether the mismatch was induced by the threshold voltage variation or by the current factor variation. We further evaluated the HD by directly using the experimental I D ?CV GS curves to obtain more accurate values. The ??-power model, fitted to g m ?CV GS curves, described the HD more precisely, to make it more agreeable with the results obtained from the experimental data, when we used the differential current equation as a function of the transconductance (g m ), its derivative $ \left(g_{m}^{\prime}\right) $ and their variations (??g m and ?? $g_{m}^{\prime}\, $ ). 相似文献
315.
Differential scanning calorimetry (DSC) was used for the direct analysis of melting properties in porcine subcutaneous, intermuscular, and kidney leaf adipose tissue by heating at a constant ratio of +5 °C/min from 4 to 90 °C. Melting curves for adipose tissues as well as fat extracted from the associated tissues by chloroform–methanol were generated using DSC. Major peaks in DSC curves were similar among types of adipose tissue but the temperatures of the melting peak and conclusion point differed among types of adipose tissues. From the visual appearance of fat samples it appeared that the major DSC peak corresponded to phase transition of the fat. The direct DSC analysis of porcine adipose tissues may be useful to determine melting properties. 相似文献
316.
Hori H Nagaoka Y Yamamoto A Sano T Yamashita N Taniyasu S Kutsuna S Osaka I Arakawa R 《Environmental science & technology》2006,40(3):1049-1054
Decomposition of perfluorooctanesulfonate (PFOS) and related chemicals in subcritical water was investigated. Although PFOS demonstrated little reactivity in pure subcritical water, addition of zerovalent metals to the reaction system enhanced the PFOS decomposition to form F-ions, with an increasing order of activity of no metal approximately equal Al < Cu < Zn < Fe. Use of iron led to the most efficient PFOS decomposition: When iron powder was added to an aqueous solution of PFOS (93-372 microM) and the mixture was heated at 350 degrees C for 6 h, PFOS concentration in the reaction solution fell below 2.2 microM (detection limit of HPLC with conductometric detection), with formation of F-ions with yields [i.e., (moles of F- formed)/(moles of fluorine content in initial PFOS) x 100] of 46.2-51.4% and without any formation of perfluorocarboxylic acids. A small amount of CHF3 was detected in the gas phase with a yield [i.e., (moles of CHF3)/(moles of carbon content in initial PFOS) x 100] of 0.7%, after the reaction of PFOS (372 microM) with iron at 350 degree C for 6 h. Spectroscopic measurements indicated that PFOS in water markedly adsorbed on the iron surface even at room temperature, and the adsorbed fluorinated species on the iron surface decomposed with rising temperature, with prominent release of F- ions to the solution phase above 250 degrees C. This method was also effective in decomposing other perfluoroalkylsulfonates bearing shorter chain (C2-C6) perfluoroalkyl groups and was successfully applied to the decomposition of PFOS contained in an antireflective coating agent used in semiconductor manufacturing. 相似文献
317.
Mitoma Y Tasaka N Takase M Masuda T Tashiro H Egashira N Oki T 《Environmental science & technology》2006,40(6):1849-1854
The authors achieved highly efficient degradation of polychlorinated aromatic compounds, including polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like compounds such as coplanar polychlorinated biphenyls (co-PCBs), which are known as persistent organic pollutants. Degradation was accomplished in 24 h through a simple stirring operation using safe and high workability metallic calcium, which acts as both a scavenger and a reducing agent, and Rh/C catalyst in an alcohol solution under mild conditions in a sealed tube at 25 degrees C without a temperature increase within 0.15 MPa of increasing internal pressure during the reaction. In this system, reductive dechlorination by metallic calcium and catalytic reduction by Rh/C and generated hydrogen gas, without any external addition of hydrogen, exert a synergistic effect on the degradation of chlorinated compounds. Alcohol was used as a proton source and hydrogen, which was generated by a side reaction, causes an increase in the activity of Rh/C catalyst. Through the degradation of 4-chloroanisole in ethyl alcohol, anisole and cyclohexyl methyl ether were obtained in good conversions. Using ethyl alcohol as a solvent, treatment of dioxins and co-PCBs in a solution was markedly effective for degradation to reduce 2806 pg TEQ/ml of initial concentration to 31.8 pg TEQ/ml; its yield was 98.5%. Moreover, degradation in methyl alcohol took place in a 99.3% yield. That concentration ultimately reached 20.3 pg TEQ/ml under a mild wet process. All congeners of dioxins and co-PCBs were degraded in high conversions. In this degradation, lower aliphatic alcohol, such as methyl alcohol, is effective for making a new calcium surface as compared to alcohol with more methylene chains. In addition, it seemed that a higher pressure of hydrogen was easily generated in methyl alcohol, and then catalytic degradation was effectivley influenced. 相似文献
318.
Yamaki K. Kitagawa N. Mochiku T. Matsuhita Y. Funahashi S. Irie A. 《Journal of Superconductivity and Novel Magnetism》2021,34(8):2207-2215
Journal of Superconductivity and Novel Magnetism - Single-crystal growth of rutheno-cuprate materials EuSr2RuCu2O8?δ (RuEu-1212) and (Eu, Ce)2Sr2RuCu2O10?δ (RuEu-1222), where... 相似文献
319.
Masaya Fujioka Melbert Jeem Kento Sato Masashi Tanaka Kazuki Morita Taizo Shibuya Kiyonori Takahashi Suguru Iwasaki Akira Miura Masanori Nagao Satoshi Demura Hideaki Sakata Madoka Ono Hideo Kaiju Junji Nishii 《Advanced functional materials》2023,33(10):2208702
Intercalation into 1D transition metal trichalcogenides (TMTs) in which fibers are bonded by a weak van der Waals force can be expected to create various intercalation compounds and develop unique physical properties according to the combination of the host materials and guest ions. However, structural changes via intercalation into 1D TMTs are not as simple as those in 2D transition metal dichalcogenides (TMDs) and are still not understood comprehensively. ZrTe3: a typical compound with a 1D trigonal prismatic structure, belongs to TMTs. Herein, through the Ag introduction to ZrTe3 via solid-state intercalation, a novel crystal phase with a 1D octahedral structure and a quasi-amorphous (QA) phase during the structural transition are discovered; the QA phase is a novel state of matter in which long-range order is lost while retaining 1D order. Based on the Ag concentration, the transport properties are flexibly modulated from superconductivity to semiconductivity. Density functional theory calculations indicate the attraction between Ag ions and the pair diffusion due to their attraction. Furthermore, judging the attraction or repulsion between guest ions predicts whether to induce a QA phase or simple lattice expansion like the intercalation into 2D TMDs. 相似文献