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981.
Summary A simple and sensitive method is presented for determination of styrene, toluene, ethylbenzene, isopropylbenzene andn-propylbenzene in human body fluids by capillary gas chromatography (GC) with cryogenic oven trapping. After heating a blood
or urine sample containing each compound andp-diethylbenzene (internal standard, IS) in a 7.0-mL vial at 60°C for 20 min, 5 mL of headspace vapor was drawn into a glass
syringe and injected into a GC. All vapor was introduced into an Rtx-Volatile middle bore capillary column in splitless mode
at oven temperature of 20°C to trap entire analytes, and the oven temperature then programmed to 280°C for GC measurements
by flame ionization detection. The present conditions gave sharp peaks of each compound and IS, and low background noises
for whole blood or urine samples. 相似文献
982.
通过410MeV 82Se轰击天然Ba靶引起的深部非弹反应布居产生了类弹和类靶余核的激发态,利用在束γ谱学方法测量了它们的退激γ.通过γ–γ符合测量估计了类弹、类靶余核激发态的产生截面,在多个类靶余核中观测到了新γ跃迁,并建立了136Ba的新能级纲图,说明利用深部非弹反应研究Z≈56,N≈80区高自旋态是有效、可行的. 相似文献
983.
O. Schließmann G. Bogatzki H. Pinsl E. Bischof G. Geuer W. M. Swenigorodskaja R. Weihrich W. Schwarz W. W. Stepin N. W. Musowskaja A. T. Tscherny E. Diepschlag L. G. Stadler I. M. Bessonow A. T. Sweschnikow T. W. Boretzkaja B. A. Ssossnowski R. Ishii A. G. Bogdantschenko S. N. Schkotowa O. Quadratund Vl. Vcělák S. Mischoinsniky 《Analytical and bioanalytical chemistry》1942,124(11-12):429-441
984.
Masayuki Nishi Masahiro Komeda Naoto Aoyagi Yoshiaki Yoshida Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2020,58(15):2126-2133
4-(1,3-Dithia-2-thioxocyclopenthyl)methacrylate (TCMA), containing the five-membered trithiocarbonate moiety, was prepared from glycidyl methacrylate (GMA) through 2,3-epithiopropyl methacrylate (ETMA). At first step, GMA was converted to ETMA by the reaction using thiourea. At second step, ETMA was reacted efficiently with carbon disulfide in the presence of a catalytic amount of 1,2-dimethyltetrahydropyrimidine to give TCMA. The polymerization of TCMA proceeded under standard radical conditions to give the polymeric TCMA in 94% yield. The copolymerizations of TCMA with ethyl acrylate (EA) or acrylonitrile (AN) were conducted by changing the feed molar ratios of the monomers, in which the corresponding copolymers were obtained in over 83% yields. In addition, the obtained polymers showed the high values of refractive index over ca. 1.6 due to the presence of the cyclic trithiocarbonate structure. 相似文献
985.
986.
The Ramanujan Journal - We explicitly compute the complex archimedean part of the Godement–Jacquet zeta integral. We give a pair of a Schwartz–Bruhat function and a matrix coefficient... 相似文献
987.
Naoto Kumano-go 《Bulletin des Sciences Mathématiques》2011,(8):936-987
We give two general classes of functionals for which the phase space Feynman path integrals have a mathematically rigorous meaning. More precisely, for any functional belonging to each class, the time slicing approximation of the phase space path integral converges uniformly on compact subsets with respect to the starting point of momentum paths and the endpoint of position paths. Each class is closed under addition, multiplication, translation, real linear transformation and functional differentiation. Therefore, we can produce many functionals which are phase space path integrable. Furthermore, though we need to pay attention for use, the interchange of the order with the integrals with respect to time, the interchange of the order with some limits, the semiclassical approximation of Hamiltonian type, the natural property under translation, the integration by parts with respect to functional differentiation, and the natural property under orthogonal transformation are valid in the phase space path integrals. 相似文献
988.
989.
A convenient synthesis of δ,γ-unsaturated amino acids has been developed. After a mixture of (R)-tert-butanesulfinamide and glyoxylic acid with molecular sieves in CH2Cl2 was stirred for 42 h at room temperature, allylboronic acid pinacol ester was added to the mixture to give (R)-2-((R)-tert-butanesulfinamido)pent-4-enoic acid with high diastereoselectivity. The corresponding reaction of (Z)-crotylboronic acid pinacol ester produced no product; however, that of (E)-crotylboronic acid pinacol ester produced (2R,3S)-2-((R)-tert-butylsulfinamido)-3-methylpent-4-enoic acid with excellent diastereoselectivity. 相似文献
990.
Ken Hatano Tetsuya Yamazaki Koji Yoshino Naoto Ohyama Tetsuo Koyama Koji Matsuoka Daiyo Terunuma 《Tetrahedron letters》2008,49(39):5593-5596
A novel O-protected lactose (Galβ1→4Glcβ1-) derivative bearing trimethoxysilyl group at the aglycon was developed as a silane coupling agent. Reaction of the coupling agent with tris(2,2′-bipyridine)ruthenium (II) dichloride (Rubpy) doped silica particle gave a Rubpy-doped silica particle peripherally functionalized with O-protected lactose derivative. De-O-protection of the particle with aqueous ammonia provided lactose-coating Rubpy-doped silica particles, combining luminophor encapsulated in silica matrix and carbohydrate having lectin-recognition ability. Specific adhesion of fluorescein isothiocyanate-labeled peanut agglutinin (FITC-PNA) to the lactose-coating Rubpy-doped silica particles was confirmed by fluorescence microscopic analysis. 相似文献