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671.
Hayashi N Sato K Sato Y Iwagami M Nishimura N Yoshino J Higuchi H Sato T 《The Journal of organic chemistry》2011,76(14):5747-5758
Statistical studies using the Cambridge Structural Database have revealed that there are several elongated phenoxide C-O bonds. They are characterized by the formation of 3-fold (or occasionally 2-fold) hydrogen bonds to the phenoxide oxygen atoms, and their mean bond length extends up to 1.320 ?, which is quite different from the theoretically predicted carbon-oxygen bond length of C(6)H(5)O(-) (1.26 ?). Elongated phenoxide C-O bonds associated with the formation of 3-fold hydrogen bonds were also observed in the X-ray structures of proton-transfer complexes (2X-O(-))(TEAH(+))s derived from 5'-X-substituted 5,5'-dimethyl-1,1':3',1'-terphenyl-2,2',2'-triols (2X-OHs, where X = NO(2), CN, COOCH(3), Cl, F, H, and CH(3)) and triethylamine (TEA). By comparing the X-ray structures, C-O bond elongation was found to be only slightly affected by an electron-withdrawing substituent at the para position (X). This along with strong bathochromic shifts of N-H(···O(-)) and O-H(···O(-)) stretching vibrations in the IR spectra indicates that the elongated C-O bonds in (2X-O(-))(TEAH(+))s essentially have single-bond character. This is further confirmed by molecular orbital calculations on a model complex, showing that the negatively charged phenoxide oxygen atom is no longer conjugated to the central benzene ring, and the NICS values of the three benzene rings are virtually identical. However, C-O bond elongation in (2X-O(-))(TEAH(+))s was considerably influenced by a change in the hydrogen-bond geometry. This also suggests that hydrogen bonds significantly affect phenoxide C-O bond elongation. 相似文献
672.
We investigated the thermal degradation of LiF:Mg,Cu,P (NTL-250) and LiF:Mg,Cu,Si (MCS) for the development of TL sheet. By thermogravimetry and differential scanning calorimetry (TG-DSC), the exothermic reaction was observed between 320 °C and 400 °C in MCS as well as NTL-250. The heat value of MCS was twice as large as that of NTL-250. This ratio corresponded with that of Mg amount in these TL materials measured by ICP-OES (inductively-coupled plasma optical emission spectrometry). X-ray diffraction (XRD) measurements were also carried out, and the peaks of MgF2 phase were also observed in degraded MCS sample as well as NTL-250. Moreover, X-ray absorption near-edge structures (XANES) of Cu in these LiF TLDs were measured. The valences of Cu did not change before and after degradation. It indicates that the thermal degradation is caused by not Cu but Mg ion state change. The exothermic reaction is possible caused by the stabilization reactions, and then it was expected to correspond with MgF2 precipitation. From these results, we concluded that the thermal degradations of these LiF TLDs are caused by the precipitation of MgF2. 相似文献
673.
Shinohara Y Imai R Kishimoto H Yagi N Amemiya Y 《Journal of synchrotron radiation》2010,17(6):737-742
An indirectly illuminated X-ray area detector is employed for X-ray photon correlation spectroscopy (XPCS). The detector consists of a phosphor screen, an image intensifier (microchannel plate), a coupling lens and either a CCD or CMOS image sensor. By changing the gain of the image intensifier, both photon-counting and integrating measurements can be performed. Speckle patterns with a high signal-to-noise ratio can be observed in a single shot in the integrating mode, while XPCS measurement can be performed with much fewer photons in the photon-counting mode. By switching the image sensor, various combinations of frame rate, dynamic range and active area can be obtained. By virtue of these characteristics, this detector can be used for XPCS measurements of various types of samples that show slow or fast dynamics, a high or low scattering intensity, and a wide or narrow range of scattering angles. 相似文献
674.
Kazuki OKURA Yusuke TAKAHASHI Kakeru HASEGAWA Kazutoshi HATAKEYAMA Kimio SAITO Chihiro IMAIZUMI Hajime KAGA Naoto TAKAHASHI 《Physical Therapy Research》2022,25(3):156
Introduction: Early implementation of neuromuscular electrical stimulation (NMES) has been reported to prevent muscle atrophy and physical functional decline in patients requiring mechanical ventilation. However, its effect in patients with acute exacerbation of interstitial lung disease (ILD) remains unclear. We herein report our experience using the NMES combined with mobilization in a patient with an acute exacerbation of rheumatoid arthritis-associated ILD (RA-ILD) requiring mechanical ventilation. Case Presentation: A 74-year-old man was admitted to the intensive care unit (ICU) and put on mechanical ventilation due to severe acute exacerbation of RA-ILD. Early mobilization and the NMES using a belt electrode skeletal muscle electrical stimulation system were started on day 7 of hospitalization (day 2 of ICU admission). The NMES duration was 20 min, performed once daily. The patient could perform mobility exercises on day 8 and could walk on day 16. We assessed his rectus femoris and quadriceps muscle thicknesses using ultrasound imaging, and found decreases of 4.5% and 8.4%, respectively, by day 14. On day 27, he could independently visit the lavatory, and the NMES was discontinued. He was instructed to start long-term oxygen therapy on day 49 and was discharged on day 63. His 6-minute walk distance was 308 m and his muscle thickness recovered to levels comparable to those at the initial evaluation at the time of discharge. Conclusion: Combining the NMES and mobilization started in the early phase and continued after ICU discharge was safe and effective in a patient with a severe acute exacerbation of RA-ILD. 相似文献
675.
Dr. Tatsuhiro Kojima Hiroto Takeda Dr. Naoto Kuwamura Prof. Takumi Konno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(64):15981-15985
Solvent-mediated crystal-to-crystal transformations of [Au6Ag3Cu3(H2O)3(d -pen)6(tdme)2]3+ (d -[ 1 (H2O)3]3+; pen2−= penicillaminate, tdme=1,1,1-tris(diphenylphosphinomethyl)ethane) to form unique supramolecular species are reported. Soaking crystals of d -[ 1 (H2O)3]3+ in aqueous Na2bdc (bdc2−=1,4-benzenedicarboxylate) yielded crystals containing d -[ 1 (bdc)(H2O)2]+ due to the replacement of a terminal aqua ligand in d -[ 1 (H2O)3]3+ by a monodentate bdc2− ligand. When γ-cyclodextrin (γ-CD) was added to aqueous Na2bdc, d -[ 1 (H2O)3]3+ was transformed to d -[ 1 (bdc@γ-CD)(H2O)2]+, where a γ-CD ring was threaded by a bdc2− molecule to construct a pseudorotaxane structure. While the use of dicarboxylates with an aliphatic carbon chain instead of bdc2− afforded analogous pseudorotaxanes, such pseudorotaxane species were not formed when crystals of [Au6Ag3Cu3(H2O)3(l -pen)6(tdme)2]3+ (l -[ 1 (H2O)3]3+) enantiomeric to d -[ 1 (H2O)3]3+ were soaked in aqueous Na2bdc and γ-CD, affording only crystals containing l -[ 1 (bdc)(H2O)2]+. 相似文献
676.
Naoto Shida 《Mathematische Nachrichten》2023,296(10):4806-4834
In this paper, bilinear pseudo-differential operators with symbols in the bilinear Hörmander class are considered. In particular, the boundedness of these operators on Sobolev spaces is established. Our main result is proved by using symbolic calculus and the boundedness of those operators with certain S0, 0-type symbols on Lebesgue spaces. 相似文献
677.