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101.
Haruo Shimada Katsuyuki Maeno Kazumasa Kinoshita Yasuo Shida 《Journal of the American Society for Mass Spectrometry》2017,28(11):2393-2400
A novel method for the simultaneous detection of ingredients in pharmaceutical applications such as creams and lotions was developed. An ultrasonic atomizer has been used to produce a mist containing ingredients. The analyte molecules in the mist can be ionized by using direct analysis in real time (DART) at lower temperature than traditionally used, and we thus solved the problem of normal DART-MS measurement using a high-temperature gas. Thereby, molecular-related ions of heat-unstable components and nonvolatile components became detectable. The deprotonated molecular ion of glycyrrhizic acid (m/z 821), which is unstable at high temperatures, was detected without pyrolysis by ultrasonic mist–DART-MS using unheated helium gas, although it was not detected by normal DART-MS using heated helium gas. The cationized molecular ions of derivatives of polyethylene glycol fatty acid monoesters, which are nonvolatile compounds, were also detected as m/z peaks observed from 800 to 2300. Although the protonated molecular ion of tocopherol acetate was not detected in ionization by ultrasonic mist, it was detected by ultrasonic mist–DART-MS even in the emulsion. It was not necessary to dissolve a sample completely to detect its ions. This method enabled us to obtain the composition of pharmaceutical applications simply and rapidly. 相似文献
102.
Let K denote a field, and let V denote a vector space over K with finite positive dimension. By a Leonard pair on V we mean an ordered pair of linear transformations A : V → V and A∗ : V → V that satisfy the following two conditions:
- (i)
- There exists a basis for V with respect to which the matrix representing A is irreducible tridiagonal and the matrix representing A∗ is diagonal.
- (ii)
- There exists a basis for V with respect to which the matrix representing A∗ is irreducible tridiagonal and the matrix representing A is diagonal.
103.
104.
T. Yamaguchi K. TanakaT. Suzuki A. OzawaT. Ohtsubo T. AibaN. Aoi H. BabaM. Fukuda Y. HashizumeK. Inafuku N. IwasaT. Izumikawa K. KobayashiM. Komuro Y. KondoT. Kubo M. KurokawaT. Matsuyama S. Michimasa T. MotobayashiT. Nakabayashi S. NakajimaT. Nakamura H. SakuraiR. Shinoda M. ShinoharaH. Suzuki M. TakechiE. Takeshita S. TakeuchiY. Togano K. YamadaT. Yasuno M. Yoshitake 《Nuclear Physics A》2011,864(1):1-37
Reaction cross sections with various kinds of breakup channels for neutron-rich carbon isotopes 18-20C and for 9Be impinging on a liquid hydrogen target were investigated at 40 MeV/nucleon. The nuclides of interest were produced via projectile fragmentation from a 63 MeV/nucleon 40Ar beam and were separated in flight at the RIKEN projectile fragment separator (RIPS). The combination of the large-acceptance superconducting TOF spectrometer, TOMBEE (TOF Mass analyzer for exotic BEam Experiment), with a liquid hydrogen target, CRYPTA (CRYogenic ProTon and Alpha target system), enables simultaneous measurements of several reaction channels: the reaction cross sections (σR), individual elemental fragmentation cross sections (σΔZ), charge-changing cross sections (σcc), neutron-removal cross sections (σ−xn), and charge-pickup cross sections (σΔZ+1) for 19,20C; σΔZ, σ−xn, and σΔZ+1 for 18C; and σR for 9Be. The present σR of 9Be on proton, σR=397±23 mb, measured in the inverse kinematics, was consistent with the previous measurements using proton beams at different laboratories. The σR of 19C and 20C on proton were determined to be σR=754±22 mb and σR=791±34 mb, respectively. Taking into account the beam energy and target dependence of σR, the present σR are found to be considerably enhanced compared with those measured at around 1 GeV/nucleon. The σΔZ+1 appears to increase with the mass number of the projectiles, and it significantly contributes to σR in the present energy range. The finite-range optical-limit and few-body Glauber model analyses were performed for σR to study the nuclear matter density distributions and to derive the relative strength of the s-wave components of the valence neutrons in 19C and 20C. A neutron halo structure of 19C is confirmed with an s-wave dominance of the valence neutron when the effect of the charge-pickup reaction is taken into account. The large σ−n of 19C and σ−2n of 20C also support the decoupled structures of 18C +n and 18C+2n, respectively. The σcc of 19C and 20C agree with each other within their experimental uncertainties, which might indicate a similar proton density distribution in 19C and 20C. The σΔZ decreases monotonically without the even-odd effect as the number of removed protons increases. 相似文献
105.
The organocatalytic asymmetric direct aldol reaction of trifluoroacetaldehyde ethyl hemiacetal with aromatic methyl ketones in the presence of a catalytic amount of (S)-5-(pyrrolidin-2-yl)-1H-tetrazole in dichloroethane at 40 °C proceeds smoothly to produce (R)-4,4,4-trifluoro-1-aryl-3-hydroxy-1-butanones in high yields with up to 90% ee. 相似文献
106.
Funabiki K Matsunaga K Gonda H Yamamoto H Arima T Kubota Y Matsui M 《The Journal of organic chemistry》2011,76(1):285-288
A complete reversal of diastereoselectivity was observed for reactions of the trifluoroacetaldehyde ethyl hemiacetal with enamines and imines, derived from propiophenones, that produce 4,4,4-trifluoro-1-aryl-3-hydroxy-2-methyl-1-butanones. This process serves as the first reliable, metal-free, complementary anti- and syn-selective method to prepare 4,4,4-trifluoro-1-aryl-3-hydroxy-2-methyl-1-butanones. 相似文献
107.
Tamaki M Harada T Fujinuma K Takanashi K Shindo M Kimura M Uchida Y 《Chemical & pharmaceutical bulletin》2012,60(6):743-746
To find candidates with high antimicrobial and low hemolytic activities, many gratisin (GR) analogues have been designed and synthesized. In the present account, we synthesized novel derivatives of GR having both the polycationic and fatty acyl groups, cyclo{-Val(1)-Orn(2)-Leu(3)-D-Phe(4)-Pro(5)-D-Lys(6)(X)-Val(7)-Orn(8)-Leu(9)-D-Phe(10)-Pro(11)-D-Lys(12)-} {X=-CO(CH(2))(6)CH(3) (1), -Lys-CO(CH(2))(6)CH(3) (2), -(Lys)(2)-CO(CH(2))(6)CH(3) (3), and -(Lys)(3)-CO(CH(2))(6)CH(3) (4)}, and examined the biological activities. Among them, we found that 2-4 have differential ionic interaction against the prokaryotic membrane and eukaryotic membrane. In other words, the dissociation with high antimicrobial activity and low hemolytic activity is caused by the addition of D-Lys(6)-{(Lys)(n)-CO(CH(2))(6)CH(3)} residues at position 6 of [D-Lys(6,12)]-GR. Our findings should be helpful in finding drug candidates with high antimicrobial activity and low hemolytic activity that are capable of combating microbial resistance. 相似文献
108.
J. W. Hwang Y. Satou T. Nakamura Y. Kondo N. Matsui Y. Hashimoto T. Nakabayashi T. Okumura M. Shinohara N. Fukuda T. Sugimoto H. Otsu Y. Togano T. Motobayashi H. Sakurai Y. Yanagisawa N. Aoi S. Takeuchi T. Gomi M. Ishihara S. Kawai H. J. Ong T. K. Onishi S. Shimoura M. Tamaki T. Kobayashi Y. Matsuda N. Endo M. Kitayama 《Few-Body Systems》2013,54(7-10):1469-1472
The 16C nucleus has been investigated by the neutron knockout reaction of 17C on a liquid hydrogen target. Applying the invariant mass method in inverse kinematics and γ-ray spectroscopy, the energy spectrum was reconstructed by triple-coincidence measurement, in which neutrons, charged fragments, and γ rays from the decay of the reaction residue (16C*) were detected. A peak at 0.47 MeV was observed in the invariant mass spectrum in coincidence with a peak at 0.74 MeV in the γ-ray spectrum, which indicates the presence of an unbound state with an excitation energy of 5.46 MeV. Comparison of the experimental cross section with the value derived by a theoretical calculation provided evidence that the spin-parity of this state is 2?. 相似文献
109.
Reiko Azumi Kazumasa Honda Midori Goto Junji Akimoto Yoshinao Oosawa Hiroaki Tachibana 《Molecular Crystals and Liquid Crystals》2013,570(1-2):237-243
Abstract The aromatic ammonium-based layered halide compounds were obtained of bis(4-nitroanilinium)tetrachlorocadmate and bis(2-methyl-4-nitroanilinium) tetrachlorocadmate, aiming at a new type of inorganic-organic hybrid layered material. X-ray diffraction analyses of the single crystals revealed that both of the crystals take an alternate layered structure of the organic bilayer and the inorganic sheet. Cadmium ion and chloride anions form six-coordinated octahedra whose corner anions are shared with the neighboring octahedra for the crystal of bis(4-nitroanilinium)tetrachlorocadmate. In the case of bis(2-methyl-4-nitroanilinium) tetrachlorocadmate crystal the inorganic portion takes distorted four-coordinated tetrahedra. The structure of the inorganic portion for the latter crystal can be considered to be caused by the distortion of a perovskite-type octahedron due to the introduction of a bulky organic molecule. 相似文献
110.
Z.X. CaoY.L. Ye J. XiaoL.H. Lv D.X. JiangT. Zheng H. HuaZ.H. Li X.Q. LiY.C. Ge J.L. LouR. Qiao Q.T. LiH.B. You R.J. ChenD.Y. Pang H. SakuraiH. Otsu M. NishimuraS. Sakaguchi H. BabaY. Togano K. YonedaC. Li S. WangH. Wang K.A. LiT. Nakamura Y. NakayamaY. Kondo S. DeguchiY. Satou K. Tshoo 《Physics letters. [Part B]》2012,707(1):46-51
We report for the first time the discrimination of the core fragment knockout and valence nucleon knockout reaction mechanisms at medium energy range, by the use of the recoil proton tagging technique. Intense 8He beams at 82.3 MeV/u were supplied by the RIPS beam line at RIKEN, and impinged on both hydrogen and carbon targets. Recoil protons were detected in coincidence with the forward moving core fragments and neutrons. The core fragment knockout mechanism is identified through the polar angle correlation and checked by various kinematics relations. This mechanism may be used to extract the cluster structure information of unstable nuclei. On the other hand, with the selection of the tagged valence nucleon knockout mechanism, a narrower peak of 7He ground state is obtained. The extracted neutron spectroscopic factor Sn=0.512(18) is relatively smaller than the no-tagged one, and is in good agreement with the prediction of ab initio Green?s function Monte Carlo calculations. 相似文献