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121.
The sol–gel reaction of a polycarbonate (PC) oligomer having triethoxysilyl groups at both ends of the PC chain (PCS) with a tetraethoxysilane or tetramethoxysilane oligomer provided transparent or semitransparent films of higher silica containing organic–inorganic hybrid materials (HSPC‐HMs). The films were superior to those from PC and from PCS in terms of the morphological homogeneity, heat resistance, and surface hardness. The HSPC‐HM films had minimum oxygen permeability at a PCS/tetraethoxysilane ratio of 3/7. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4273–4279, 2006 相似文献
122.
The 13C n.m.r. spectra of chicle polyisoprene and cis-trans isomerized 1, 4-polyisoprenes were studied. The splittings of signals were observed in the C1, C2, and C4 carbon signals of the isomerized polyisoprenes. The newly appearing signals were assigned to the carbon atoms in cis-trans linkages. The fractions of the diad sequences (trans-trans, trans-cis, cis-trans, and cis-cis) were determined by using the four signals of C1 carbon. It was found that the cis-1, 4- and trans-1, 4-units were randomly distributed in the isomerized polyisoprenes and it was confirmed that the chicle polyisoprene was a mixture of cis-1, 4- and trans-1, 4-polyisoprenes. 相似文献
123.
Masahiro Endo Yasuyuki Morishima Shinichi Yano Kenji Tadano Yukinobu Murata Kenji Tsunashima 《应用聚合物科学杂志》2006,101(6):3971-3978
Miscibility was studied for four polyamide blends of 6I/6T [copolymer consisting of 1,6‐hexamethylene diamine and isophthalic acid (6I) (70 wt %) and terephthalic acid (6T) (30 wt %)] with MXD6 (polyamide of m‐xylenediamine and adipic acid), BAC6 (polyamide of 1,3‐bis(aminomethyl)cyclohexane and adipic acid), TR55 (copolymer consisting of nylon 11 (30 wt %), and polyamide of bis(3‐methyl, 4‐aminocyclohexyl)methane (30 wt %) and isophthalic acid (70 wt %), and CX7323 (polyamide of bis(4‐aminocyclohexyl)methane and dodecanedicarboxylic acid), using differential scanning calorimetry, X‐ray diffraction method, and electronmicroscopic observation. In quenched MXD6/(6I/6T) and BAC6/(6I/6T) blends, MXD6 and BAC6 components were miscible to 6I/6T, but TR55 and CX7323 components were completely phase‐separated from 6I/6T. Interestingly on electronmicroscopic observations, TR55 and CX7323 components were seen as droplets in 6I/6T medium when the content is low, but when 50 wt %, a layered structure was constructed with 6I/6T, reminiscent of morphological structure in block copolymer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3971–3978, 2006 相似文献
124.
Atsushi Iizuka Takeshi Sasaki Masato Honma Hiroyuki Yoshida Yasuyuki Hayakawa Yukio Yanagisawa 《Chemical Engineering Communications》2017,204(1):79-85
A pilot-scale plant to treat concrete sludge and produce calcium carbonate (CaCO3) and an environmental purification agent (phosphorus adsorbent derived from concrete sludge, PAdeCS®) was designed, constructed, and operated. Concrete sludge from a concrete pile and pole production plant, boiler gas containing CO2, and groundwater were used in the plant. The process involved calcium extraction from concrete sludge into water, followed by reaction of the calcium with CO2 to produce crystalline CaCO3. The pilot-scale plant was operated for 1 week, and the mass flows, conversion of CO2 to CaCO3, and net CO2 emissions of the process were estimated. High-purity CaCO3 (>97%) suitable for industrial use was obtained. Based on the power consumption of the process and the amount of CO2 sequestered into CaCO3, a net reduction in CO2 emissions can be achieved using this process. The produced PAdeCS can be used as an inexpensive substitute for calcium series environmental purification agents. 相似文献
125.
Tomoko Hirano Shinsuke Kato Shuzo Murakami Toshiharu Ikaga Yasuyuki Shiraishi 《Building and Environment》2006
This study targets environmental load reduction in hot and humid regions. It reveals the effects that porous residential buildings have on the natural ventilation performance and, consequently, the cooling load reduction. Two residential building models, namely a model with a void ratio of 0% and a model with a void ratio of 50%, are evaluated using computational fluid dynamics (CFD) analysis and thermal and airflow network analysis. The analysis on components of the heat load indicates that improvements in the natural ventilation performance would significantly reduce the cooling load. 相似文献
126.
Niidome T Akiyama Y Shimoda K Kawano T Mori T Katayama Y Niidome Y 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(7):1001-1007
Gold nanorods showing surface plasmon (SP) bands in the near-IR region are used as bioimaging probes that respond to near-IR light in mice. The SP bands of intravenously injected polyethylene glycol-modified gold nanorods are directly monitored from the mouse abdomen by using a spectrophotometer equipped with an integrating sphere. The absorbance at 900 nm from the gold nanorods immediately increases after injection and reaches a plateau. The injection of phosphatidylcholine-modified gold nanorods also increases the absorbance at 900 nm, but the absorbance decreases single exponentially with a 1.3-min half-life. In vivo spectral changes of gold nanorods depend on the surface characteristics, and can be observed in real time using simple spectroscopic measurements. 相似文献
127.
128.
Tanaka T Takahashi K Sako K Kasegawa R Toishi M Watanabe K Samuels D Takeya M 《Applied optics》2007,46(17):3583-3592
An external-cavity laser with a wavelength of 405 nm and an output of 80 mW has been developed for holographic data storage. The laser has three states: the first is a perfect single mode, whose coherent length is 14 m; the second is a three-mode state with a coherent length of 3 mm; and the third is a six-mode state with a coherent length of 0.3 mm. The first and second states are available for angular-multiplexing recording; all states are available for coaxial multiplexing recording. Due to its short wavelength, the recording density is higher than that of a 532 nm laser. 相似文献
129.
Nagasako-Akazome Y Kanda T Ohtake Y Shimasaki H Kobayashi T 《Journal of oleo science》2007,56(8):417-428
We performed a randomized double-blind, placebo-controlled study on moderately obese male and female subjects (71 subjects) with a body mass index ranging from 23 to 30 to evaluate the efficacy of 12-week intake of polyphenols extracted from apples and hop bract (600 mg/day). We confirmed that 12-week ingestion of polyphenol-containing capsules significantly decreased total cholesterol and LDL-cholesterol levels. The effects of the apple polyphenol-containing capsules were more marked than those of the hop bract polyphenol-containing capsules. The visceral fat area and the level of adiponectin in the group administered apple polyphenols improved in comparison with the control group. Blood and physical examinations revealed on clinical problems, and no adverse reactions were observed during the ingestion period. These results demonstrate that apple polyphenols regulate fat metabolism in healthy subjects with relatively high body mass index. 相似文献
130.
Yamamoto N Muramoto A Yoshinaga J Shibata K Endo M Endo O Hirabayashi M Tanabe K Goto S Yoneda M Shibata Y 《Environmental science & technology》2007,41(18):6357-6362
We compared the status of carbonaceous aerosols in Tokyo before and after the implementation of a diesel vehicle regulation intended to reduce the quantity of particulate carbon from diesel engines in one of the largest scale ever attempts at vehicle exhaust control. Radiocarbon (14C) in elemental carbon (EC) and total carbon (TC) were analyzed to identify fossil fuel carbonaceous particles emitted from diesel-powered vehicles. One-sided paired-month t-tests showed no distinct difference in the absolute concentrations of particles in terms of total mass (19.5 to 18.0 microg m(-3); p = 0.321), EC (3.6 to 3.3 microg m(-3); p = 0.272), and TC (6.3 to 6.2 microg m(-3); p = 0.418) for the finest particles (d(a) < 1.1 microm) after the implementation of the regulation. The ratios of the concentrations of the chemical constituents were, however, altered after the regulation. EC/TC was significantly decreased from 56.7% to 50.2% (p = 0.039). Although it was not statistically significant, the percentage of fossil carbon in EC also decreased (67.8% to 63.8%; p = 0.104). Since EC is predominantly of combustion origin, the observed decrease was likely due to the decrease in fossil EC emissions from diesel-powered vehicles. The decrease in EC/TC after the implementation of the regulation was also likely to have resulted from attachment to diesel vehicle exhaust systems of particulate filters as required as part of the regulation by the Tokyo Metropolitan Government. The EC/TC of fossil carbon of the finest particles decreased from 66.2% to 55.2% (p = 0.066), but EC/TC of biomass carbon did not decrease but rose slightly from 43.6% to 44.5% (p > 0.5). Thus, the relative ratios of components of carbonaceous aerosol particles, such as 14C, could provide a better understanding of the atmospheric pollution status, despite short-term fluctuations, than do measurements of absolute concentrations. 相似文献