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321.
Inagaki T Shinozuka Y Yamada K Yonenobu H Hayashida A Tsuchikawa S Yoshida A Hoshino Y Gotanda K Yasuda Y 《Applied spectroscopy》2012,66(6):673-679
This study explored the feasibility of rapid, nondestructive near-infrared (NIR) reflection spectroscopy for the prediction of conventional physical properties, carbon-nitrogen-sulfur (CNS) analysis, and concentration of inorganic components in sediment cores from a brackish lake. A long core sample, which consisted of well-preserved annually formed lamina from Lake Ogawara along the Pacific coast in Aomori Prefecture, northeastern Japan, was used to investigate the past environmental record. The core was previously analyzed for physical properties, CNS, and inorganic components. Calibration models were developed from NIR reflection spectra of 149 core samples. Partial least squares (PLS) analysis provided good regression models between measured and predicted values for water content, total nitrogen (TN), total organic carbon (TOC), total sulfur (TS), Al(2)O(3), S/Al(2)O(3), Fe(2)O(3)/Al(2)O(3), Sc/Al(2)O(3), Cu/Al(2)O(3), and Zn/Al(2)O(3) with coefficients of determination (r(2)) for cross-validation of 0.73, 0.89, 0.88, 0.73, 0.92, 0.81, 0.82, 0.75, 0.82, and 0.82, respectively. The variation of predicted component values as a function of depth showed the same trend as that of conventionally measured values. This study also showed the possibility of NIR spectroscopy as an on-site, rapid analytical tool for the identification of tephra (fragmental material produced by a volcanic eruption regardless of composition, fragment size, or emplacement mechanism), which is important for dating. 相似文献
322.
Genta Kamiya Nobuo Kitada Tadaomi Furuta Takashi Hirano Shojiro Maki Sung Bae Kim 《International journal of molecular sciences》2022,23(21)
The present study introduces a unique BL signature imaging system with novel CTZ analogues named “C-series.” Nine kinds of C-series CTZ analogues were first synthesized, and BL intensity patterns and spectra were then examined according to the marine luciferases. The results show that the four CTZ analogues named C3, C4, C6, and C7, individually or collectively luminesce with completely distinctive BL spectral signatures and intensity patterns according to the luciferases: Renilla luciferase (RLuc), NanoLuc, and artificial luciferase (ALuc). The signatural reporters were multiplexed into a multi-reporter system comprising RLuc8.6-535SG and ALuc16. The usefulness of the signatural reporters was further determined with a multi-probe system that consists of two single-chain probes embedding RLuc8 and ALuc23. This study is a great addition to the study of conventional bioassays with a unique methodology, and for the specification of each signal in a single- or multi-reporter system using unique BL signatures and patterns of reporter luciferases. 相似文献
323.
Shigenori Mitsushima Yoshitsugu Shinohara Koichi Matsuzawa Ken-ichiro Ota 《Electrochimica acta》2010,55(22):6639-10436
To use the protonic mesothermal fuel cell without humidification, mass transportation in diethylmethylammonium trifluoromethanesulfonate ([dema][TfO]), trifluoromethanesulfuric acid (TfOH)-added [dema][TfO], and phosphoric acid (H3PO4)-added [dema][TfO] was investigated by electrochemical measurements. The diffusion coefficient and the solubility of oxygen were ca. 10−5 cm2 s−1 and ca. 10−3 M (=mol dm−3), respectively. Those of hydrogen were a factor of 10 and one-tenth compared to oxygen, respectively. The permeability, which is a product of the diffusion coefficient and solubility, of oxygen and hydrogen were almost the same for the perfluoroethylenesulfuric acid membrane and the sulfuric acid solution; therefore, these values are suitable for fuel cell applications. On the other hand, a diffusion limiting current was observed for the hydrogen evolution reaction. The current corresponded to ca. 10−10 mol cm−1 s−1 of the permeability, and the diffusion limiting species was the hydrogen carrier species. The TfOH addition enhanced the diffusion limiting current of [dema][TfO], and the H3PO4 addition eliminated the diffusion limit. The hydrogen bonds of H3PO4 or water-added H3PO4 might significantly enhance the transport of the hydrogen carrier species. Therefore, [dema][TfO] based materials are candidates for non-humidified mesothermal fuel cell electrolytes. 相似文献
324.
Takayuki Honda Rong Lu Nobuhiko Kitano Yoshimi Kamiya Tetsuo Miyakoshi 《应用聚合物科学杂志》2010,118(2):897-901
Three lacquer samples taken from a “four‐eared” pottery container, which was designated an important National Cultural Property of Japan excavated in 16–17th century ruins of Kyoto City, were analyzed by pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS) and infrared (IR) spectroscopy to determine the source of the lacquer. It is an unexpected result that the lacquer in this pottery container is actually used by Melanorrhoea usitata. Alkylbenzene and alkenylbenzene as cleavage pieces of undecylbenzene (MW = 232 g/mol) and undecenylbenzene (MW = 230 g/mol), which are products of the pyrolysis of thitsiol, were detected in all three samples. Moreover, ω‐phenylalkylcatechols and ω‐phenylalkylphenols, which are the specific components of M. usitata, were also detected by Py‐GC/MS, suggesting that lacquer sap of M. usitata was used by the Japanese people in the 16–17th centuries. In addition, Japanese lacquer culture and the advantages of the Py‐GC/MS method for lacquer analysis are discussed in detail. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
325.
Dr. Yoshitsugu Morita Keisuke Igarashi Ryosuke Funaki Prof. Dr. Teruyuki Komatsu 《Chembiochem : a European journal of chemical biology》2019,20(13):1684-1687
Covalent wrapping of recombinant human hemoglobin (Cys-β93→Ala) variant rHb(βC93A) by human serum albumin (HSA) yielded the rHb(βC93A)-HSA3 cluster as an artificial O2 carrier as a red blood cell substitute. Complexation of inositol hexaphosphate to the central rHb(βC93A) core reduced the O2 affinity moderately, in much the same way as that of naked hemoglobin. This reduction might be attributable to the inert, small Ala-β93 residue, which cannot be reacted with the bulky maleimide crosslinker. 相似文献
326.
The effect of thermal residual stress on the two-dimensional interlaminar crack extension behavior in a cross-ply laminate subjected to transverse loading is estimated. Attention is focused on the contribution of thermal residual stress to the local energy release rate along the interlaminar crack front. Computational simulations are carried out on the basis of constant critical energy release rates in order to examine implicitly how the two-dimensional size and shape would be changed by the presence of thermal residual stress. A considerably large amount of energy is found to be supplied for the interlaminar crack extension by thermal residual stress, while little influence is perceived with respect to the apparent extension behavior including the shape of the interlaminar crack. 相似文献
327.
Yoshitsugu Maruhashi 《Polymer Engineering and Science》2001,41(12):2194-2199
The thermal shrinkage of heat‐set polyethylene terephthalate (PET) sheets at 85°C after stretching at low speed and low temperature was similar to that for sheets stretched at high speed and high temperature if the crystallinities of these sheets were the same. However, differences between other physical properties, such as yield strength, were observed, which may be due to differences in the amorphous phase. The sheets stretched at the higher temperature and higher speeds may have different structures in the molecular segments in the amorphous phase, more relaxed than in the sheets prepared at the lower speed and temperature. 相似文献
328.
Chemiluminescent determination of cholesterol hydroperoxides in human erythrocyte membrane 总被引:6,自引:5,他引:1
Junko Adachi Migiwa Asano Takeaki Naito Yasuhiro Ueno Yoshitsugu Tatsuno 《Lipids》1998,33(12):1235-1240
A method for separating, detecting, and quantifying cholesterol hydroperoxide (Ch-OOH) based on extraction, purification by solid-phase extraction cartridge, high-performance liquid chromatography with chemiluminescent detection (HPIC-CI), and liquid chromatography mass spectrometry has been developed for human erythrocyte membrane. We prepared standard compounds of the cholesterol 5α-, 7α-, and 7β-hydroperoxides (Ch 5α-OOH, Ch 7α-OOH, and Ch 7β-OOH). An octyl silica column with methanol/water/acetonitrile 89∶9∶2 (by vol) as eluent was used to determine Ch-OOH. HPLC-CL that incorporated cytochrome c and luminol as the post-column luminescent reagent was used. We also investigated the optimal assay conditions and how to prevent formation of artifact Ch-OOH. Analysis of erythrocyte membranes from seven healthy volunteers identified Ch 7α-OOH and Ch 7β-OOH, but not Ch 5α-OOH, as commonly occurring components. The respective mean concentrations of Ch 7α-OOH and Ch 7β-OOH were 2,5±1.6 and 5A±3.5 pmol/mL blood. 相似文献
329.
ABSTRACT The extraction experiments of copper from aqueous solutions of copper sulfate by LIX65N-kerosene solutions were carried out at 25°C in liquid-liquid dispersions. Both reaction rates of the forward and backward extractions were obtained in a stirred vessel, being combined with the equilibrium data. For a multistage column in continuous operation, the holdup data of the dispersed organic phase were correlated with the stirring speed, flow rates and LIX65N concentration. It was found that the extracted fraction of copper in the multi-stage column can be predicted from a stage-to-stage calculation using the extraction kinetics and the holdup obtained in the present work. 相似文献
330.
Prof. Dr. Yoshitsugu Akiyama Kazunori Kimura Dr. Syuuhei Komatsu Dr. Tohru Takarada Prof. Dr. Mizuo Maeda Prof. Dr. Akihiko Kikuchi 《Chembiochem : a European journal of chemical biology》2023,24(1):e202200451
A colorimetric assay of DNA cleavage by bleomycin (BLM) derivatives was developed utilizing high colloidal stability on double-stranded (ds) DNA-modified gold nanoparticles (dsDNA-AuNPs) possessing a cleavage site. The assay was performed using dsDNA-AuNPs treated with inactive BLM or activated BLM (Fe(II)⋅BLM). A 10-min exposure in dsDNA-AuNPs with inactive BLM treatment resulted in a rapid color change from red to purple because of salt-induced non-crosslinking aggregation of dsDNA-AuNPs. In contrast, the addition of active Fe(II)⋅BLM retained the red color, probably because of the formation of protruding structures at the outermost phase of dsDNA-AuNPs caused by BLM-mediated DNA cleavage. Furthermore, the results of our model experiments indicate that oxidative base release and DNA-cleavage pathways could be visually distinguished with color change. The present methodology was also applicable to model screening assays using several drugs with different mechanisms related to antitumor activity. These results strongly suggest that this assay with a rapid color change could lead to simple and efficient screening of potent antitumor agents. 相似文献