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排序方式: 共有1317条查询结果,搜索用时 15 毫秒
101.
Higuchi M Miyata D Kawamura S Ueda E Imanaka M Tonogai Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(6):339-343
Daily intakes of 12 phenols which are possible endocrine disruptors were estimated in hospital meals from 2000 to 2001. 4-Nonylphenol (4-NP (mix)) and bisphenol A (BPA) were detected at levels of 5.0 to 19.4 ng/g and 0.2 to 1.1 ng/g, respectively. 4-tert-Butylphenol, 4-n-pentylphenol, 4 -tert-pentylphenol, 4-n-hexylphenol, 4-n-heptylphenol and 4-tert-octylphenol were detected at levels of 0.1 to 2.4 microg/g. The daily intakes of 4-NP (mix) and BPA were 5.8 microg/day and 0.42 microg/day, respectively. The daily intakes of other phenols were less than 1 microg/day. 相似文献
102.
A series of hyper-branched polyimide (HBPI)/mesoporous SiO2 nanocomposite films were prepared from a fluorinated anhydride (6FDA), a fluorinated triamine (TFAPOB), and mesoporous SiO2 nanoparticles (NPs). The anhydride-terminated precursor of HBPI was functionalized using a coupling agent prior to mixing with SiO2 NPs. The morphologies and thermal-optical properties of the nanocomposite films were investigated, with particular focus on their optical transparency, refractive indices (n), and thermo-optical (TO) coefficients. The absolute values of TO coefficients (|dn/dT|) of HBPI film (50.8 ppm/K) were significantly reduced to 13.4 ppm/K by homogeneous dispersion of 15 wt% of SiO2 NPs. The HBPI/SiO2 composite films exhibited high thermal stability without significant weight loss of up to 400 °C in air. The films also exhibited small coefficients of linear thermal expansion (CTEs) within the range 30–40 ppm/K. In addition, enhanced interfacial interactions between SiO2 and HBPI significantly improve the optical transparency with cutoff wavelengths shorter than 450 nm. The refractive indices of HBPI/SiO2 composite films were found to range from 1.477 to 1.502, which agrees well with the calculated values. This study shows that the incorporation of SiO2 NPs in multi-functional HBPI matrix is a promising approach to prepare high performance thermally stable films for thermo-optic applications. 相似文献
103.
Daisuke Tashima Eri Yamamoto Nanami Kai Daisuke Fujikawa Go Sakai Masahisa Otsubo Tsuyoshi Kijima 《Carbon》2011,(14):4848-4857
Micro-mesoporous bimodal carbon nanospheres with high surface areas were synthesized by a combined use of surfactant templating technique and BaO2 chemical activation one. Starting spherical nanopolymer/surfactant composites were prepared by the NaOH-catalyzed reaction of resorcinol (R) and formaldehyde (F) in the presence of cetyltrimethylammonium bromide (CTAB) as a core template and 1,3,5-trimethylbenzene (TMB) and tert-butanol (t-BuOH) as cosurfactants. After pretreatment with hydrochloric acid, the composite materials were calcined at 1000 °C in N2 coexistent with varying weight ratios of BaO2 to RF polymer ranging from 0 to 11. It produced micro-mesoporous bimodal carbon nanospheres of 124–143 nm diameter, with specific surface areas as high as 1884 m2 g−1 or up to 3301 m2 g−1, in contrast to microporous ones with smaller surface areas obtained at low BaO2-loadings. The electrochemical double layer capacitance of the resulting nanocarbons in 0.5 M H2SO4 showed a marked increase with specific surface areas, up to as high as 219 F g−1 for the highest surface area carbon material. 相似文献
104.
Daisuke Kawashima Yutaka Asako 《International Journal of Heat and Mass Transfer》2012,55(9-10):2244-2248
This paper focuses on temperature rise due to the viscous dissipation in liquids flowing through micro-channels. In the past, equations for the prediction of the temperature rise have been obtained as a function of the friction factor, Reynolds number and Eckert number or a similar form, starting from Navier–Stokes equation and energy equation under the assumption of fully developed laminar flow by researchers. The temperature rises calculated from the equations have been compared with experimental data and the equations have been validated. However, in this paper, a new equation for the prediction of the temperature rise is simply obtained from the first law of thermodynamics without restriction of fully developed laminar flow. 相似文献
105.
Crosslinked poly(N-benzyl-4-vinyipyridinium bromide) has been found to be digested by activated sludge obtained from sewage works. As an extension of this work, the authors attempted to make poly(methyl methacrylate) biodegradable by incorporation of a pyridinium group. Poly(methyl methacrylate) containing a small amount of N-benzyl-4-vinylpyridinium chloride in the main chain showed remarkable reduction in molecular weight and gravimetric weight when placed in an aeration tank of a sewage works. Molecular weight reduction by activated sludge was more conspicuous when content of the pyridinium group was larger and the original molecular weight before the biological treatment was lower. Since insoluble pyridinium-type polymer captures microbial cells alive, this biodegradation appears to be facilitated by enhancement of affinity of the synthetic hydrophobic polymer with cells of microogranisms. © 1994 John Wiley & Sons, Inc. 相似文献
106.
We classified fractures of the base of the middle phalanx into five types: 1) single palmar fragment; 2) single dorsal fragment; 3) two main fragments; 4) not involving the articular surface, including epiphyseal separation in children; and 5) all others. Types 1 and 2 were subclassified into avulsion, split and split-depression. Surgery is recommended for unstable type-1 avulsion fractures, type-2 avulsions which may develop buttonhole deformities, and all fractures which displace articular cartilage surfaces. Long-term follow-up showed that surgical treatment which produced good stability and congruity gave good results. These should be the primary aims of treatment. 相似文献
107.
Takanori Kondo Chihiro Yasui Dr. Taisuke Banno Prof. Dr. Kouichi Asakura Dr. Tokuma Fukuoka Dr. Kazunori Ushimaru Dr. Maito Koga Dr. Hiroyuki Minamikawa Dr. Azusa Saika Dr. Tomotake Morita Prof. Dr. Daisuke Takahashi Prof. Dr. Kazunobu Toshima 《Chembiochem : a European journal of chemical biology》2022,23(2):e202100631
Mannosylerythritol lipids (MELs), which are one of the representative sugar-based biosurfactants (BSs) produced by microorganisms, have attracted much attention in various fields in the sustainable development goals (SDGs) era. However, they are inseparable mixtures with respect to the chain length of the fatty acids. In this study, self-assembling properties and structure-activity relationship (SAR) studies of recovery effects on damaged skin cells using chemically synthesized MELs were investigated. It was revealed, for the first time, that synthetic and homogeneous MELs exhibited significant self-assembling properties to form droplets or giant vesicles. In addition, a small difference in the length of the fatty acid chains of the MELs significantly affected their recovery effects on the damaged skin cells. MELs with medium or longer length alkyl chains exhibited much higher recovery effects than that of C18-ceramide NP. 相似文献
108.
Gaowa Bai Daisuke Furushima Toshiro Niki Takashi Matsuba Yosuke Maeda Atsushi Takahashi Toshio Hattori Yugo Ashino 《International journal of molecular sciences》2021,22(9)
Numbers of patients with coronavirus disease 2019 (COVID-19) have increased rapidly worldwide. Plasma levels of full-length galectin-9 (FL-Gal9) and osteopontin (FL-OPN) as well as their truncated forms (Tr-Gal9, Ud-OPN, respectively), are representative inflammatory biomarkers. Here, we measured FL-Gal9, FL-OPN, Tr-Gal9, and Ud-OPN in 94 plasma samples obtained from 23 COVID-19-infected patients with mild clinical symptoms (CV), 25 COVID-19 patients associated with pneumonia (CP), and 14 patients with bacterial infection (ID). The four proteins were significantly elevated in the CP group when compared with healthy individuals. ROC analysis between the CV and CP groups showed that C-reactive protein had the highest ability to differentiate, followed by Tr-Gal9 and ferritin. Spearman’s correlation analysis showed that Tr-Gal9 and Ud-OPN but not FL-Gal9 and FL-OPN, had a significant association with laboratory markers for lung function, inflammation, coagulopathy, and kidney function in CP patients. CP patients treated with tocilizumab had reduced levels of FL-Gal9, Tr-Gal9, and Ud-OPN. It was suggested that OPN is cleaved by interleukin-6-dependent proteases. These findings suggest that the cleaved forms of OPN and galectin-9 can be used to monitor the severity of pathological inflammation and the therapeutic effects of tocilizumab in CP patients. 相似文献
109.
Daisuke Uta Takumi Oti Tatsuya Sakamoto Hirotaka Sakamoto 《International journal of molecular sciences》2021,22(7)
The spinal ejaculation generator (SEG) is located in the central gray (lamina X) of the rat lumbar spinal cord and plays a pivotal role in the ejaculatory reflex. We recently reported that SEG neurons express the oxytocin receptor and are activated by oxytocin projections from the paraventricular nucleus of hypothalamus (PVH). However, it is unknown whether the SEG responds to oxytocin in vivo. In this study, we analyzed the characteristics of the brain–spinal cord neural circuit that controls male sexual function using a newly developed in vivo electrophysiological technique. Optogenetic stimulation of the PVH of rats expressing channel rhodopsin under the oxytocin receptor promoter increased the spontaneous firing of most lamina X SEG neurons. This is the first demonstration of the in vivo electrical response from the deeper (lamina X) neurons in the spinal cord. Furthermore, we succeeded in the in vivo whole-cell recordings of lamina X neurons. In vivo whole-cell recordings may reveal the features of lamina X SEG neurons, including differences in neurotransmitters and response to stimulation. Taken together, these results suggest that in vivo electrophysiological stimulation can elucidate the neurophysiological response of a variety of spinal neurons during male sexual behavior. 相似文献
110.