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61.
62.
63.
Chang MS Hamley CD Barrett MD Sauer JA Fortier KM Zhang W You L Chapman MS 《Physical review letters》2004,92(14):140403
We measure spin mixing of F=1 and F=2 spinor condensates of 87Rb atoms confined in an optical trap. We determine the spin mixing time to be typically less than 600 ms and observe spin population oscillations. The equilibrium spin configuration in the F=1 manifold is measured for different magnetic fields and found to show ferromagnetic behavior for low field gradients. An F=2 condensate is created by microwave excitation from the F=1 manifold, and this spin-2 condensate is observed to decay exponentially with time constant 250 ms. Despite the short lifetime in the F=2 manifold, spin mixing of the condensate is observed within 50 ms. 相似文献
64.
Alejandra Gómez-Torres Dr. J. Rolando Aguilar-Calderón Angela M. Encerrado-Manriquez Dr. Maren Pink Dr. Alejandro J. Metta-Magaña Prof. Dr. Wen-Yee Lee Prof. Dr. Skye Fortier 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(13):2803-2807
Two electron-reduction of the TiIV guanidinate complex (ImDippN)(Xyketguan)TiCl2 gives (η6-ImDippN)(xyketguan)Ti ( 1intra ) and (ImDippN)(Xyketguan)Ti(η6-C6H6) ( 1inter ) (Xyketguan=[(tBuC=N)C(NXylyl)2]−, Xylyl=2,5-dimethylphenyl) in the absence or presence of benzene, respectively. These complexes have been found to hydrogenate monocyclic and polycyclic arenes under relatively mild conditions (150 psi, 80 °C)—the first example of catalytic, homogeneous arene hydrogenation with TON >1 by a Group IV system. 相似文献
65.
66.
n.O.e. difference spectra reveal that the preferred solution conformation of methyl enol ethers has the methyl group -periplanar to the double bond; n.O.e kinetics in a methoxy—heptatriene demonstrate the presence of both possible periplanar conformations, the energy difference being 1 kcal/mole. 相似文献
67.
F. Azaiez S. Fortier S. Galès E. Hourani J.M. Maison J. Kumpulainen J.P. Schapira 《Nuclear Physics A》1985,444(3):373-401
The γ-decay of the deeply-bound hole states in 111Sn has been investigated at 32 MeV incident energy by means of the 112Sn(3He, αγ) reaction. The α-particles emitted near 0° were detected in a Si counter located at the image plan of the superconducting solenoidal spectrometer SOLENO. The γ-rays in coincidence with the α-particles were detected by two Ge(Li) detectors located at 90° and 142° with respect to the beam direction, respectively. Energies, spins and decay schemes have been established for the low-lying states up to 2.5 MeV excitation energy in 111Sn. The γ-decay of the broad bump, located around 4.2 MeV and previously attributed to neutron pick-up from the inner neutron. Subshells, reveals the importance of quasiparticle-phonon m the spreading mechanism of the inner-hole strengths. The and 2p strength functions have been deduced from the α-decay of the enhanced structures (3 ≦ Ex≦ 8 MeV). They are compared to the ones measured in previous inclusive neutron pick-up experiments and to those calculated in the framework of the quasiparticle-phonon nuclear model. 相似文献
68.
Thach‐Mien D. Nguyen SeChin Chang Brian Condon Minori Uchimiya Chanel Fortier 《先进技术聚合物》2012,23(12):1555-1563
A novel flame retardant diethyl 4‐methylpiperazin‐1‐ylphosphoramidate (CN‐3) containing phosphorous and nitrogen was prepared. Its chemical structure was confirmed by nuclear magnetic resonance (1H‐, 13C‐, and 31P‐NMR), Fourier transform infrared spectroscopy, and elemental analysis. Print cloth and twill fabrics were treated with CN‐3 to achieve different levels of add‐on (7–22 wt% add‐ons for print cloth and 3–18 wt% add‐ons for twill). Thermogravimetric analysis, vertical flame test, and limiting oxygen index (LOI) were performed on the treated cotton fabrics and showed promising results. When the treated print cloth and twill fabric samples were tested using the vertical flame test (ASTM D6413‐08), we observed that the ignited fabrics self‐extinguished and left behind a streak of char. Treated higher add‐ons fabrics were neither consumed by flame nor produced glowing ambers upon self‐extinguishing. LOI (ASTM 2863–09) was used to determine the effectiveness of the flame retardant on the treated fabrics. LOI values increased from 18 vol% oxygen in nitrogen for untreated print cloth and twill fabrics to maximum of 28 and 31 wt% for the highest add‐ons of print cloth and twill, respectively. The results from cotton fabrics treated with CN‐3 demonstrated a higher LOI value as well as a higher char yield because of the effectiveness of phosphorus and nitrogen as a flame retardant for cotton fabrics. Furthermore, FT‐IR and SEM were used to characterize the chemical structure on the treated fabrics as well as the surface morphology of char areas of treated and untreated fabrics. Published 2012. This article is a US Government work and is in the public domain in the USA. 相似文献
69.
A host-guest optical sensor for the determination of aliphatic amines as exemplified by octylamine is proposed. It is based
on the reversible fluorescence enhancement of heptakis(2,6-di-O-isobutyl)-β-cyclodextrin(DOB-β-CD) hosting tetraphenylporphyrin
(TPP) immobilized in poly(vinyl chloride) (PVC) membrane by aliphatic amine extracted from aqueous phase into membrane phase.
The optimum membrane contained 1.15 wt % TPP, 6.15 wt % DOB-β-CD as sensing reagent and other membrane materials. The fluorescence
enhancement of the membrane resulted from the formation of a stable three-component complex among DOB-β-CD, TPP, and aliphatic
amines. With the optimum conditions described, the fluorescence response of the sensor to octylamine shows a good correlation
with the theoretically derived equation in the range 1.0 × 10–6 to 8.0 × 10–4 mol/L. The response characteristics including reversibility, response time, reproducibility and lifetime and selectivity
of this optical device are also discussed in detail. This sensor has also been applied for the determination of octylamine
in water samples containing interferents with satisfactory recovery.
Received: 21 November 1999 / Revised: 10 January 2000 / Accepted: 15 January 2000 相似文献
70.
M. S. Golovkov L. V. Grigorenko A. S. Fomichev A. V. Gorshkov V. A. Gorshkov S. A. Krupko Yu. Ts. Oganessian A. M. Rodin S. I. Sidorchuk R. S. Slepnev S. V. Stepantsov G. M. Ter-Akopian R. Wolski A. A. Korsheninnikov E. Yu. Nikolskii V. A. Kuzmin B. G. Novatskii D. N. Stepanov S. Fortier P. Roussel-Chomaz W. Mittig 《The European physical journal. Special topics》2007,150(1):23-26
The spectrum of 9He was studied by means of the
8He(d,p)9He reaction at a lab energy of 25 MeV/n and
small center of mass (c.m.) angles. Energy and angular
correlations were obtained for the 9He decay products by
complete kinematical reconstruction.
The data analysis was done in the assumption of a direct one-neutron transfer
reaction
mechanism. The 9He structure was analysed in the framework of a simple
single-particle model.
The lowest resonant state of 9He is found at about 2 MeV with a width of ∼2MeV and is identified as 1/2-. The
observed angular correlation pattern is uniquely explained by the
interference of the 1/2- resonance with a virtual state 1/2+
(a limit on the scattering length is obtained as a
> -20fm), and with a 5/2+ resonance at energy ≥4.2MeV. 相似文献