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991.
Photo-induced molecular alignment behavior of azo dye derivative (sodium 4,4′-bis (4-hydroxy-3-carboxy-phenylazo) benzidine-2,2′-disulphonate: SD1) was investigated using SD1 film prepared by spin-coating method. As-prepared SD1 film was composed of an amorphous layer with smooth surface. Upon linearly polarized UV light irradiation, the film surface was roughened slightly and X-ray diffraction measurement and transmittance electron microscope observation indicated that SD1 molecules crystallized with orientation. Molecular plane of SD1 aligned parallel to the substrate surface along the normal to the polarization direction of irradiated UV light through the trans-cis and cis-trans isomerizations of the azobenzene chromophore. 相似文献
992.
To understand the relationship between molecular chirality and electrical properties of monolayers, Maxwell displacement current (MDC) behaviors and domain shapes of chiral DPPC monolayers composed of dextro- (d-) and levo- (l-) rotatory molecules at the air-water interface are investigated during monolayer compression using MDC measurement and the Brewster angle microscopy (BAM) system. The experimental results show that for DPPC monolayers of the two pure enantiomers, the π-A isotherms and the MDC behaviors are similar to each other, while the domain patterns of them are mirror shapes of different sizes. This reveals that MDC behaviors due to molecular spontaneous polarization have no relation to chirality but domain shapes closely depend on the molecular chirality. Moreover, the observed domain shapes verify the domain shape theory which was recently developed by Iwamoto et al. [M. Iwamoto, Z.C. Ou-Yang, Phy. Rev. Letts, 93 (2004) 206101]. 相似文献
993.
(Ti,Cr,Al,Si)N films were deposited by cathodic arc method using TiCrAlSi alloy cathodes. It was found that the microstructures of (Ti,Cr,Al,Si)N were closely related to (Al+Si) content. The crystal structure of (Ti,Cr,Al,Si)N was NaCl-type structure up to the (Al+Si) content of 0.60, where it changed to a hexagonal structure. The maximum hardness of 33 GPa was obtained at the lowest (Al+Si) content of 0.56, still in the cubic structure. The micro-hardness decreased down to 28 GPa as the crystal structure changed from NaCl-type to wurtzite-type.To investigate the thermal stabilities of (Ti,Cr,Al,Si)N, the films were annealed in a vacuum furnace. In Ti0.20Cr0.20Al0.55Si0.05N with cubic structure, the phase segregation occurred by annealing at over 900 °C, while Ti0.22Cr0.22Al0.44Si0.12N remained in cubic phase up to 1000 °C. The micro-hardness of Ti0.20Cr0.20Al0.55Si0.05N increased and that of Ti0.22Cr0.22Al0.44Si0.12N decreased at 1000 °C. Ti0.20Cr0.11Al0.58Si0.11N with a cubic and hexagonal mixture phase held its (c,h)-mixture phase up to 1000 °C, while there was an indication of an increase both in micro-hardness and in cubic ratio after annealing.In this paper, the micro-hardness and microstructure of (Ti,Cr,Al,Si)N are discussed as a function of annealing temperature and investigated by X-ray diffraction and electron microscopy. 相似文献
994.
Subhash Chandra Ghosh Joyce S. Y. Ngiam Christina L. L. Chai Abdul M. Seayad Tuan Thanh Dang Anqi Chen 《Advanced Synthesis \u0026amp; Catalysis》2012,354(8):1407-1412
A practical and efficient method for the synthesis of amides has been developed by iron‐catalysed oxidative amidation of aldehydes with amine hydrochloride salts. A wide range of amides have been obtained in good to excellent yields under mild conditions. The application of this novel amide formation reaction to the synthesis of pharmaceutical compounds has been successfully demonstrated. 相似文献
995.
Mechanisms of hydrogen sulfide removal with steel making slag 总被引:1,自引:0,他引:1
K Kim S Asaoka T Yamamoto S Hayakawa K Takeda M Katayama T Onoue 《Environmental science & technology》2012,46(18):10169-10174
In the present study, we experimentally investigated the removal of hydrogen sulfide using steel-making slag (SMS) and clarified the mechanism of hydrogen sulfide removal with the SMS. The results proved that SMS is able to remove hydrogen sulfide dissolved in water, and the maximum removal amount of hydrogen sulfide per unit weight of the SMS for 8 days was estimated to be 37.5 mg S/g. The removal processes of hydrogen sulfide were not only adsorption onto the SMS, but oxidation and precipitation as sulfur. The chemical forms of sulfide adsorbed onto the SMS were estimated to be sulfur and manganese sulfide in the ratio of 81% and 19%, respectively. It is demonstrated here that the SMS is a promising material to remediate organically enriched coastal sediments in terms of removal of hydrogen sulfide. Furthermore, using SMS is expected to contribute to development of a recycling-oriented society. 相似文献
996.
Kondo T Kaburagi Y Shibata M Kurokawa C Inoue Y Yamamoto Y Miyazaki M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2012,53(2):75-84
A simple clean-up method was developed for the simultaneous determination of pesticide residues in livestock products by GC-MS/MS. The pesticide residues were extracted with acetonitrile-ethanol (1 : 1), and matrix components such as adipose were effectively eliminated by a combination of refrigerated centrifugation, dispersive solid-phase extraction, and multifunctional column chromatography. In this method, samples are treated quickly and easily without the need for gel-permeation chromatography. Among 131 pesticides tested, 115 showed recovery within the range from 70 to 120%, with relative standard deviations of less than 15%. The quantification limits for the 115 pesticides in livestock products were 0.001 to 0.01 μg/g. 相似文献
997.
Yamamoto Y 《Chemical reviews》2012,112(8):4736-4769
998.
Hartt LS Carling SJ Joyce MM Johnson GA Vanderwall DK Ott TL 《Reproduction (Cambridge, England)》2005,130(2):241-250
Uterine function is primarily controlled by the combined actions of oestrogen and progesterone working through their cognate nuclear receptors. The mechanism of establishment of pregnancy in the mare is of interest because it involves prolonged pre-attachment and conceptus migration phases, and both invasive and non-invasive placental cell types, and as such has been an important comparative model. This study characterised regulation of oestrogen (ER) and progesterone (PR) receptors in the endometrium of the mare during the oestrous cycle and early pregnancy. Endometrial tissues collected during the oestrous cycle and early pregnancy were analysed for steady-state levels of ER and PR mRNA and protein. Steady-state levels of ER and PR mRNA were highest on days 0, 17 and 20 in cyclic mares and lowest on days 11 and 14. A day-by-status interaction was detected, indicating that day 17 and day 20 pregnant mares exhibited low levels of ER and PR compared with the corresponding days of the oestrous cycle. In situ hybridisation analyses showed receptor mRNA localisation primarily in the luminal epithelium (LE), glandular epithelium (GE) and stroma around oestrus. During dioestrus and early pregnancy, receptors were not detected in the LE, and were lower in the stroma and deeper GE. Changes in hybridisation intensity in these cell types were consistent with changes in mRNA levels detected by slot-blot hybridisation. ER and PR proteins were detected in the nuclei of LE, GE and stromal cells. Consistent with results from in situ hybridisation, levels of ER and PR immunoreactivity were higher around oestrus, declined to low levels during dioestrus and remained low during early pregnancy. Results described here for temporal and spatial changes in steroid receptor gene expression in mares show the greatest similarities with those described for cattle and sheep. 相似文献
999.
1000.
Kurauchi K Nakaguchi Y Tsutsumi M Hori H Kurihara R Hashimoto S Ohnuma R Yamamoto Y Matsuoka S Kawai S Hirata T Kinoshita M 《Environmental science & technology》2005,39(8):2762-2768
Detection of endocrine disrupting chemicals, in particular, environmental estrogens with living organisms, has many advantages if compared to chemical analysis. The screening of novel pollutants with meaningful endpoints, the integration of uptake, bioconcentration, and excretion as well as the evaluation of endocrine disrupting effects with respect to toxicity require in vivo biotests for estrogen-like substances (ELSs). Critical disadvantages of whole organism biotests are their low sensitivity and the need for laborious and time-consuming work. To overcome these problems, we have developed a transgenic medaka strain harboring the green fluorescence protein (GFP) gene driven by choriogenin H gene regulatory elements. Choriogenin H is an egg envelope protein induced by estrogens in the liver. With yolk sac larvae of this strain, GFP induction in liver was observed 24 h after onset of aqueous exposure to 0.63 nM 17beta-estradiol (E2), 0.34 nM ethynylestradiol, or 14.8 nM estrone. Furthermore, concentrated sewage treatment effluent induced GFP expression. Comparison of E2 equivalents estimated by GFP-induction in transgenic medaka, a YES assay, and GC/MS showed detection limits in the same order of magnitude. These results indicated that the sensitivity of the transgenic medaka strain was sufficient for application as an alternative model in monitoring environmental water samples for ELSs. 相似文献