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J.-C. Thomas L. Achouri J. Äystö R. Béraud B. Blank G. Canchel S. Czajkowski P. Dendooven A. Ensallem J. Giovinazzo N. Guillet J. Honkanen A. Jokinen A. Laird M. Lewitowicz C. Longour F. de Oliveira Santos K. Peräjärvi M. Stanoiu 《The European Physical Journal A - Hadrons and Nuclei》2004,21(3):419-435
3.
The new techniques and ideas in quantum interferometry with neutrons, photons, atoms, electrons, and Bose condensates that fluorished in the last two decades have influenced in a decisive way the thinking and the research in the foundations and interpretation of quantum mechanics. The controversies existing among different schools on the reality of matter waves of quantum theory, the postulates of quantum measurement theory, and the (in)completeness of quantum mechanics have to be approached now in a new way. Our argumentation follows the spirit of the Paris school. 相似文献
4.
We investigate a new parallel all-optical clock recovery scheme based on heterodyne beats of an optical sideband-filtered signal. The oscillating clock signal is recovered when the filtered sideband is combined with a stable local oscillator. The filtering is performed with an optical resonator, which by nature provides possibility for multiwavelength operation. The local oscillator could be realized by a multiwavelength laser, whose emission wavelengths are injection seeded with carrier wavelengths of the input data. The output signal of such a configuration benefits from a reduced bit-pattern effect and a stable offset level. The sideband filtering is demonstrated for 23 simultaneous channels at 100 GHz DWDM grid, each hosting a data stream of 10 Gbit/s. 相似文献
5.
Hiroshi Yamauchi Keiko Takahashi Mari Mashiko Juichiro Saitoh Yukio Yamamura 《应用有机金属化学》1992,6(4):383-388
We calculated the intake of each chemical species of dietary arsenic by typical Japanese, and determined urinary and blood levels of each chemical species of arsenic. The mean total arsenic intake by 35 volunteers was 195±235 (15.8-1039) μg As day?1, composed of 76% trimethylated arsenic (TMA), 17.3% inorganic arsenic (Asi), 5.8% dimethylated arsenic (DMA), and 0.8% monomethylated arsenic (MA): the intake of TMA was the largest of all the measured species. Intake of Asi characteristically and invariably occurred in each meal. Of the intake of Asi, 45-75% was methylated in vivo to form MA and DMA, and excreted in these forms into urine. The mean measured urinary total arsenic level in 56 healthy volunteers was 129±92.0 μg As dm?3, composed of 64.6% TMA, 26.7% DMA, 6.7% Asi and 2.2% MA. The mean blood total arsenic level in the 56 volunteers was 0.73±0.57 μg dl?1, composed of 73% TMA, 14% DMA and 9.6% Asi. The urinary TMA levels proved to be significantly correlated with the whole-blood TMA levels (r = 0.376; P<0.01). 相似文献
6.
Kato H Brink M Möllerstedt H Piqueras MC Crespo R Ottosson H 《The Journal of organic chemistry》2005,70(23):9495-9504
[Figure: see text]. A quantum chemical study has been performed to assess changes in aromaticity along the T1 state Z/E-isomerization pathways of annulenyl-substituted olefins. It is argued that the point on the T1 energy surface with highest substituent aromaticity corresponds to the minimum. According to Baird (J. Am. Chem. Soc. 1972, 94, 4941), aromaticity and antiaromaticity are interchanged when going from S0 to T1. Thus, olefins with S0 aromatic substituents (set A olefins) will be partially antiaromatic in T1 and vice versa for olefins with S0 antiaromatic substituents (set B olefins). Twist of the C=C bond to a structure with a perpendicular orientation of the 2p(C) orbitals (3p*) in T1 should lead to regaining substituent aromaticity in set A and loss of aromaticity in set B olefins. This hypothesis is verified through quantum chemical calculations of T1 energies, geometries (bond lengths and harmonic oscillator measure of aromaticity), spin densities, and nucleus independent chemical shifts whose differences along the T1 PES display zigzag dependencies on the number of -electrons in the annulenyl substituent of the olefin. Aromaticity changes are reflected in the profiles of the T1 potential energy surfaces (T1 PESs) for Z/E-isomerizations because olefins in set A have minima at 3p* whereas those in set B have maxima at such structures. The proper combination (fusion) of the substituents of set A and B olefins could allow for design of novel optical switch compounds that isomerize adiabatically with high isomerization quantum yields. 相似文献
7.
LDPE synthesized under two-phase conditions is known to have a good balance of blown film properties. Good optical properties and high impact strength are characteristic for two-phase LDPE grades. In order to obtain systematic information, LDPE was synthesized at several different pressures with two different melt index levels. Blown film was extruded at different output rates and melt temperatures. The influence on haze and dart drop impact was studied. Two-phase conditions were found to improve haze and dart drop impact and the improvement was impressive, especially for the low melt index grades. By increasing the output rate, the dart drop values were further improved. The influence of melt temperature on dart drop impact goes through an optimum and overall haze decreases with increasing melt temperature. For films made from two-phase grades, dart drop impact decreases as internal haze increases. For corresponding internal haze values, the films made from single-phase grades have lower dart drop values and they are somewhat scattered. 相似文献
8.
An application of coupled column ion chromatography (IC)-inductively coupled plasma mass spectrometry (ICP-MS) is presented for speciation of chromium in waste waters. By coupling an anion column with a cation column, both the cationic Cr(III) and anionic Cr(VI) species can be analyzed with detection limits below 0.5 μg/1. The separation of the interfering ions (chloride, chlorate, perchlorate, sulphate, sulphite, sulphide, thiosulphate, carbonate, cyanide and some organic compounds) from the chromium peaks is discussed, and the use of different chromium isotopes for data acquisition is compared. Based on the results, m/z 52 was considered as an ideal isotope for speciation of chromium in waste waters by the coupled column IC-ICP-MS, because it did not suffer from polyatomic interferences and due to the high sensitivity for chromium. The analysis of the waste water samples should be performed as soon as possible after sampling according to the stability tests of the species. 相似文献
9.
Yoshiyasu Ichikawa Yohei Matsukawa Mari Tamura Fumiyo Ohara Minoru Isobe Hiyoshizo Kotsuki 《化学:亚洲杂志》2006,1(5):717-723
A new method for the synthesis of urea‐linked disaccharides in aqueous media has been developed. The key feature of our approach is two strained Steyermark‐type gluco‐ and galactopyranosyl oxazolidinones. Each oxazolidinone is attached to a pyranose ring in a di‐equatorial trans‐annulation framework. Reaction of these oxazolidinones with 4‐aminohexopyranose in water proceeded smoothly to afford the urea‐tethered cellobiose and lactose analogues. The galactose‐type oxazolidinone proved to be more reactive than the glucose‐type, which is explained by the presence of an axial hydroxy group at C4 in the former. 相似文献
10.
G. Lhersonneau A. Honkanen M. Huhta P. P. Jauho A. Jokinen M. Leino M. Oinonen E. Ollikainen J. M. Parmonen J. Aysto 《Zeitschrift für Physik A Hadrons and Nuclei》1994,350(2):97-98
The decay of the new activity110Mo (t1/2=0.30(4).s) has been observed at the new IGISOL separator. Multiscaled singles,--t and -y-t coincidences were recorded. The decay scheme suggests I=2+ for the ground state of the daughter nucleus110Tc. Three 1+ levels are fed with logft values below 5, indicating no drastic change among Mo and Ru decays at the middle of the neutron shell. This experiment confirms the expectation that the new IGISOL facility will allow the identification of one or two new more neutron-rich isotopes per element in this region.Supported by the Academy of Finland. 相似文献