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41.
Rie Takagi Fabienne Duc Mats Johnsson 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):i16-i18
Single crystals of molybdenum(VI) tricopper(II) tellurium(IV) heptaoxide dichloride hemihydrate, MoCu3TeO7Cl2·0.5H2O, were synthesized via a transport reaction in sealed evacuated silica tubes. All atoms occupy general positions within the triclinic () unit cell. The building units are irregular CuO4Cl and CuO3Cl2 square pyramids, distorted TeO3+1E trigonal bipyramids (E is the lone pair of TeIV) and irregular MoO5 pyramids. The TeO3+1E, CuO4Cl and CuO3Cl2 polyhedra form (110) layers bridged by Mo atoms. The water molecules are located in [100] channels. 相似文献
42.
43.
Niikura K Kamitani R Kurogochi M Uematsu R Shinohara Y Nakagawa H Deguchi K Monde K Kondo H Nishimura S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(13):3825-3834
We have developed an effective and practical trap-and-release method based on chemoselective ligation of carbohydrates with reactive aminooxyl groups attached to the surface of nanoparticles (referred to as glycoblotting nanoparticles). These glycoblotting nanoparticles were synthesized by UV irradiation of diacetylene-functionalized lipids that contain the aminooxyl group. The glycoblotting nanoparticles captured carbohydrates in aqueous solution under mild conditions and were collected by simple centrifugation. The trapped carbohydrates were effectively released from the nanoparticles under acidic conditions to give pure oligosaccharides. This glycoblotting process reduced the time required for the purification process of carbohydrates to less than 6 h, compared to the several days needed for conventional chromatographic techniques. The oligosaccharides (N-glycan) were released from ovalbumin (glycoprotein) by PNGase F after tryptic digestion. MALDI-TOF mass spectra before purification did not show any significant signals corresponding to N-glycans because these signals were hidden by the large signals of the abundant peptides. However, after purification with the glycoblotting nanoparticles, only signals corresponding to oligosaccharides appeared. We also demonstrated a clear analysis of the oligosaccharides contained in the mice dermis by means of glycoblotting. 相似文献
44.
Investigations of the discharge for PA-CVD of TiN on steel substrates are carried out using optical emission spectroscopy. A great number of species could be identified in the discharge. The growth rate of dense layers shows a direct dependence on Ti+ intensities. The occurrence of TiN in the discharge leads to f aky, not compact layers, lowering the hardness of the layers. 相似文献
45.
Jan Paseka Sylvia Pulmannová Zdenka Riečanová 《International Journal of Theoretical Physics》2013,52(6):1994-2000
We study a generalized effect algebra of unbounded linear operators in an infinite-dimensional complex Hilbert space. This algebra equipped with a certain kind of topology allows us to show that unbounded quasi-Hermitian operators can be expressed as a difference of two infinite sums of bounded quasi-Hermitian operators. 相似文献
46.
Osamu Sato Shinya Hayami Zhong-ze Gu Kazuyuki Takahashi Rie Nakajima Akira Fujishima 《Phase Transitions》2013,86(7-8):779-785
Photo-illumination effects have been measured for the compound [Co III-LS (tmpda)(3,6-DBSQ)(3,6-DBCat)]. When the aforementioned compound was illuminated at 5 K, the magnetization value increased from w eff = 1.87 to 2.03 w B . The absorption spectra after illumination show that the absorption band at around 730 nm, which is characteristic of the [Co II-HS (tmpda)(3,6-DBSQ) 2 ] state, increased in intensity and that the charge transfer band from 3,6-DBCat to 3,6-DBSQ at 2500 nm was reduced in intensity. IR spectra show that the C-O stretching peak at 1279 cm m 1 is decreased in intensity. These results confirm that a photo-induced intra-molecular electron transfer, [Co III-LS (tmpda)(3,6-DBSQ)(3,6-DBCat)] to; [Co II-HS (tmpda)(3,6-DBSQ) 2 ], was induced. The lifetime of the metastable state at 5 K was 15 min. Furthermore, it was found that reverse valence tautomerism can be induced by exciting the Co II-HS to 3,6-DBSQ charge transfer band in metastable [Co II-HS (tmpda)(3,6-DBSQ) 2 ]. 相似文献
47.
Takashi Fujikawa Hiroko Arai Rie Suzuki Hiroshi Shinotsuka Lszl Kvr Nobuo Ueno 《Journal of Electron Spectroscopy and Related Phenomena》2008,162(3):146-157
Recoil effects of photoelectrons excited by high-energy X-rays are studied beyond the simplest approximation where elastic scatterings of photoelectrons are completely neglected (single-site approximation). At first we have shown that the simple free atom energy shift is accurately obtained within the harmonic and the single-site approximations. Beyond the single-site approximation, this simple formula does not work, but still simple classically acceptable formula can be used to explain the recoil energy shift. Illustrative numerical calculations show that the energy shifts caused by the photoelectron diffraction amounts to 5–8 meV for graphite-like carbon and about 100 meV for LiI6 cluster at ?k=5–7 keV, and show oscillations as functions of the photoelectron energy. Furthermore we discuss the recoil effects in photoemission from extended levels by use of the tight-binding approach. Our approach naturally provides not only Debye–Waller factors but also the recoil factors. In addition to the phonon excitation, we also study the recoil effects associated with plasmon losses where intrinsic and extrinsic processes can interfere each other. Only the latter can contribute to the recoil energy shift. 相似文献
48.
Sato K Yamazoe S Yamamoto R Ohata S Tarui A Omote M Kumadaki I Ando A 《Organic letters》2008,10(12):2405-2408
1,3-Diketones were synthesized from alpha,beta-unsaturated ketones by treatment with acid chlorides and Et(2)Zn in the presence of RhCl(PPh(3))3. This is a very simple and extremely chemoselective reaction to give the adduct at the alpha-position of alpha,beta-unsaturated ketones. 相似文献
49.
Kawaguchi M Ito R Honda H Endo N Okanouchi N Saito K Seto Y Nakazawa H 《Journal of chromatography. A》2008,1206(2):196-199
A simple and highly sensitive method called stir bar sorptive extraction (SBSE) and thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS), which is used for the determination of trace amounts of 5-chloro-2-(2,4-dichlorophenoxy)phenol (triclosan) in river water samples, is described. A stir bar coated with polydimethylsiloxane (PDMS) is added to a 10mL water sample and stirring is carried out for 120min at room temperature (25 degrees C) in a vial. Then, the PDMS stir bar is subjected to TD-GC-MS. The detection limit of triclosan is 5ngL(-1) (ppt). The method shows linearity over the calibration range (0.02-20mugL(-1)) and the correlation coefficient is higher than 0.997 for triclosan standard solution. The recovery of triclosan in river water samples ranges from 91.9 to 108.3% (RSD: 4.0-7.0%). This simple, accurate, sensitive, and selective analytical method may be used in the determination of trace amounts of triclosan in river water samples. 相似文献
50.
Ito R Kawaguchi M Sakui N Honda H Okanouchi N Saito K Nakazawa H 《Journal of chromatography. A》2008,1209(1-2):267-270
A method for mercury analysis and speciation in drinking water was developed, which involved stir bar sorptive extraction (SBSE) with in situ propyl derivatization and thermal desorption (TD)-GC-MS. Ten millilitre of tap water or bottled water was used. After a stir bar, pH adjustment agent and derivatization reagent were added, SBSE was performed. Then, the stir bar was subjected to TD-GC-MS. The detection limits were 0.01 ng mL(-1) (ethylmercury; EtHg), 0.02 ng mL(-1) (methylmercury; MeHg), and 0.2 ng mL(-1) (Hg(II) and diethylmercury (DiEtHg)). The method showed good linearity and correlation coefficients. The average recoveries of mercury species (n=5) in water samples spiked with 0.5, 2.0, and 6.0 ng mL(-1) mercury species were 93.1-131.1% (RSD<11.5%), 90.1-106.4% (RSD<7.8%), and 94.2-109.6% (RSD<8.8%), respectively. The method enables the precise determination of standards and can be applied to the determination of mercury species in water samples. 相似文献