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2.
G. Baldsiefen H. Hübel W. Korten U. J. van Severen J. A. Cizewski N. H. Medina D. R. Napoli C. Rossi Alvarez G. Lo Bianco S. Signorelli 《Zeitschrift für Physik A Hadrons and Nuclei》1996,355(1):337-338
High-spin states in196Pb have been populated using the reaction170Er(30Si,4n). The previously observed shears bands in this nucleus have been extended and some of their transitions have been reordered. They now form regular bands with band crossings. One of the bands splits into two pathways at high spin. 相似文献
3.
4.
Muhammad Faisal Nobuaki Sato Armando T. Quitain Hiroyuki Daimon Koichi Fujie 《国际化学动力学杂志》2007,39(3):175-180
The kinetics and pathway of hydrothermal decomposition of aspartic acid were studied using a continuous‐flow tubular reactor. The reaction was carried out in the temperature range of 200–260°C and at a pressure of 20 MPa. Deamination was the primary reaction, indicated by the presence of significant amount of ammonia, fumaric acid, or maleic acid in the products. Other reaction products were pyruvic acid, malic acid, and traces of succinic and lactic acid. Traces of alanine were also detected, showing the possibility of decomposing high‐molecular weight amino acids to obtain simple amino acids such as glycine or alanine. Results on the effect of reaction parameters demonstrated that decomposition of aspartic acid is highly temperature dependent under hydrothermal conditions. For a slight temperature difference of 60°C (from 200 to 260°C), the first‐order reaction rate constants of 0.003 significantly increased to 0.231 s?1. The activation energy was 144 kJ/mol, as calculated by the Arrhenius equation. No significant effect was exhibited by other reaction parameters such as pH and pressure. The results are useful in controlling the hydrolysis of proteinaceous materials toward high yield of aspartic acid under hydrothermal conditions. © 2007 Wiley Periodicals, Inc. 39: 175–180, 2007 相似文献
5.
Dimitri Markushevich Vladimir B. Matveev Armando Treibich 《Letters in Mathematical Physics》2006,76(2-3):109-109
6.
Andrea Bianco Giacomo Iardino Chiara Bertarelli Luciano Miozzo Giuseppe Zerbi 《Applied Surface Science》2007,253(20):8360-8364
Polyamide 6 (PA6) nanofibers were prepared from formic acid solutions by using electrospinning technique. The fibers were smooth, defects free and with diameters smaller than 200 nm. Small amounts of a perfluorinated acridine were added as dopant to the feed solution to modify the wettability of the fibers. The effect of doping on the contact angle values is well apparent. The contact angle values go from 50° of pure PA6 to 120° when 6% of acridine is added. A comparison between fibers and films of pure and doped polyamide 6 was carried out in order to determine the effect of morphology on wettability. Thermal annealing near the Tg of the polymer promoted the segregation of the molecules to the surface, reaching contact angles of 131° with smaller amounts (4%) of acridine. The surface segregation was also promoted by time aging. 相似文献
7.
Dore Augusto Clemente Armando Marzotto Giovanni Valle 《Journal of chemical crystallography》1988,18(2):147-156
The crystal and molecular structure of thiamine monochloride (C12H17N4OSCl) was determined by X-ray diffraction and refined to a finalR value of 0.042. The compound crystallizes in the monoclinic system, space groupP21/a, with cell constantsa=18.929(4),b=11.663(2),c=6.376(2) Å and=96.72(8)°. The thiamine molecule is anhydrous and unprotonated, and the torsion angles at the methylene carbon show that it possesses anF conformation. The dihedral angle value of 84.16(6)° between thiazolium and pyrimidine rings is in the normal range found for the thiamine withF conformation, protonated or not, hydrated or not. Thiamine therefore has the same conformation notwithstanding protonation or hydration, with the rings similarly oriented in all the crystal structures containing thiamine. 相似文献
8.
G. Lo Bianco K. P. Schmittgen K. O. Zell P. v. Brentano 《Zeitschrift für Physik A Hadrons and Nuclei》1989,332(1):103-104
The ratio of the B(E2) values for the 0 1 + → 2 1 + transitions in138Ce and142Ce was measured by Coulomb excitation with α-particles. From the known value of the transition probability in142Ce it results: B(E2,138Ce, 0 1 + → 2 1 + =0.45 +/?0.03 e2 b 2 相似文献
9.
Poschalko A Lancelot N Marin J Larras V Limal D Elbayed K Raya J Piotto M Briand JP Guichard G Bianco A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(18):4532-4537
A novel resin called DEUSS (perdeuterated poly(oxyethylene)-based solid support) has been prepared by anionic polymerization of deuterated [D4]ethylene oxide, followed by cross-linking with deuterated epichlorohydrin. DEUSS can be suspended in a wide range of solvents including organic and aqueous solutions, in which it displays a high swelling capacity. As measured by proton HRMAS of the swollen polymer, the signal intensity of the oxyethylene protons is reduced by a factor of 110 relative to the corresponding nondeuterated poly(oxyethylene)poly(oxypropylene) (POEPOP) resin, thus facilitating detailed HRMAS NMR studies of covalently linked molecules. This 1H NMR invisible matrix was used for the solid-phase synthesis of peptides, oligoureas, and a series of amides as well as their characterization by HRMAS NMR spectroscopy. On-bead NMR spectra of high quality and with resolution comparable to that of liquid samples were obtained and readily interpreted. The complete absence of the parasite resin signals will be of great advantage, for example, for the optimization of multistep solid-phase stereoselective reactions, and for the conformational study of resin-bound molecules in a large variety of solvents. 相似文献
10.
Armando J. L. Pombeiro Raymond L. Richards 《Monatshefte für Chemie / Chemical Monthly》1992,123(8-9):749-756
Summary Reactions oftrans-[M(N2)2(dppe)2] (A;M=Mo, W;dppe=Ph
2PCH2CH2PPh
2) with ethyldiazoacetate, N2CHCOOEt, yield the bisdiazoalkane speciestrans-[M(N2CHCOOEt)2(dppe)2], upon simple replacement of the dinitrogen ligand by ethyldiazoacetate. However, diazomethane, N2CH2, reacts withA with loss of N2 to give products which we tentatively formulate as containing methylene ligands,trans-[M(CH2)2(dppe)2].
Herstellung von Bisdiazoalkan- und ähnlichen Komplexen aus den Reaktionen von Diazoverbindungen mit Distickstoffkomplexen des Typstrans-[M(N2)2(Ph 2PCH2CH2PPh 2)2] mitM=Mo oder W
Zusammenfassung Die Reaktion vontrans-[M(N2)2(dppe)2] (A:dppe=Ph 2PCH2CH2PPh 2 undM=Mo oder W) mit Ethyldiazoacetat, N2CHCOOEt, ergab nach einfachem Austausch des Distickstoffliganden mit Ethyldiazoacetat die Bisdiazoalkanetrans-[M(N2CHCOOEt)2(dppe)2]. Diazomethan (N2CH2) hingegen reagierte mitA unter Verlust von N2 zu Produkten, die tentativ alstrans-[M(CH2)2(dppe)2] mit Methylenliganden formuliert wurden.相似文献