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81.
G. V. Pallottino 《Il Nuovo Cimento C》1990,13(1):19-33
Summary The author reports on the analysis of the data obtained with the detectors given in the title in the period 12h of February
22, 1987 to 6h of February 23, 1987, that includes the time of the ν observation with the Mont Blanc detector during SN 1987a. A very significant correlation has been observed among the data of the above detectors in a period of one or two hours which
includes the time of the Mont Blanc 5ν observation. The correlation between the g.w. data and the Kamiokande data is found
if a time of 7.8s is added to the Kamioka recorded time; this is very close to the time difference, 6.2s, between the IMB
and Kamioka large ν bursts observed at ≈7h 35 min.
To speed up publication, the proofs were not sent to the authors and were supervised by the Scientific Committee. 相似文献
82.
I. Ciufolini 《Il Nuovo Cimento C》1990,13(1):67-78
Summary After a brief discussion on the experimental tests of general relativity, we describe three new measurements of Einstein theory.
The first, already performed, is the test of the De Sitter or geodetic effect, for the Earth-Moon system. The second will
be realized with the launch of the laser ranged satellite, LAGEOS III, and will test the existence of the, never measured,
gravitomagnetic field. The third, currently being performed, is the measurement of the LAGEOS relativistic perigee advance.
To speed up publication, the proofs were not sent to the authors and were supervised by the Scientific Committee. 相似文献
83.
Bovas Abraham A. Thavaneswaran 《Annals of the Institute of Statistical Mathematics》1991,43(3):493-504
This paper formulates a nonlinear time series model which encompasses several standard nonlinear models for time series as special cases. It also offers two methods for estimating missing observations, one using prediction and fixed point smoothing algorithms and the other using optimal estimating equation theory. Recursive estimation of missing observations in an autoregressive conditionally heteroscedastic (ARCH) model and the estimation of missing observations in a linear time series model are shown to be special cases. Construction of optimal estimates of missing observations using estimating equation theory is discussed and applied to some nonlinear models.Authors were supported in part by a grant from the Natural Sciences and Engineering Research Council of Canada. 相似文献
84.
Many estimating procedures are carried out with incomplete data by means of different types of EM algorithms. They allow us
to obtain maximum likelihood parameter estimates in classical inference and also estimates based on the posterior mode in
Bayesian inference. This paper analyzes in detail the spectral radii of the Jacobian matrices algorithm as a possible way
to evaluate convergence rates. The eigenvalues of such matrices are explicitly obtained in some cases and, in all of them,
a geometric convergence rate is, at least, guaranteed near the optimum. Finally, a comparison between the leading eigenvalues
of EM and direct and approximate EM-Bayes algorithms may suggest the efficiency of each case. 相似文献
85.
Lajos Horváth 《Annals of the Institute of Statistical Mathematics》1997,49(2):271-283
We discuss the asymptotic properties of some tests to detect possible changes in the mean of linear processes. 相似文献
86.
Summary The data of 46 months of the GEOGRAV gravitational-wave antenna are analysed to search for monochromatic Doppler-shifted signals
from rotating neutron stars, in the frequency band (856.2÷859.2) Hz. Two different methods were used. With the first, the
gravitational radiation from the whole sky is investigated and a limit ofh≤1·10−21 is found. With the second method only the radiation from a single source is searched. The Galactic Centre and the Large Magellanic
Cloud are considered as sources and the limit ofh≤6·10−22 is found. 相似文献
87.
Jian-bin Song Qing-yong Chen Min-qiao Ren Xiao-hong Sun Hui-liang Zhang Hong-fang Zhang Shu-yun Wang Zhi-shen Mo 《高分子科学》2006,(2):187-193
The wide-angle X-ray diffraction (WAXD) patterns of isothermally crystallized Nylon 1212 show that γ-form crystals form below 90℃ and the α-form crystals can exist above 140℃. In the temperature range of 90-140℃, the α-form and γ-form crystals coexist. Variable-temperature WAXD exhibits that the nylon 1212 γ-form does not show crystal transition on heating, while α-form isothermally crystallized at 160℃ exhibits Brill transition at a little higher than 180℃ on heating. The multiple melting behaviors of Nylon 1212 isothermally crystallized from melt come from a complex mechanism of different crystal structures, dual lamellar population and melting-recrystallization. In polarized optical microscope (POM) observations, Nylon 1212 isothermally crystallized at 175℃ shows the ringed banded spherulites. However, at temperatures below 160℃ the ringed banded image disappears, and cross-extinct spherulites are formed. 相似文献
88.
Katsufumi Tanaka Yutaka Fujioka Atsushi Kubono Ryuichi Akiyama 《Colloid and polymer science》2006,284(5):562-567
In situ optical observations were performed for suspensions composed of carbon nanoparticles under the sinusoidal electric
field with an amplitude around 20 kV/mm (volt per micrometer) and various frequencies. For extremely diluted suspensions of
mixed fullerenes or multiwalled carbon nanotubes (MWNTs) in a silicone oil, the dark-field optical microscopy was effective
for the in situ observation of the particle behavior under the electric field. The nanoparticles in a fullerene suspension
under the sinusoidal electric field with a frequency of 100 Hz (in short, 100 Hz electric field) were aggregated to form a
rigid spherical microstructure around the halfway between the electrodes. On the other hand, the nanoparticles in an MWNT
suspension under 100 Hz electric field were also aggregated but aligned to form a chain-like microstructure which spans the
electrodes. Both of the aggregated particles were stable even after the removal of the electric field, and they were redispersed
by application of 10 Hz electric field. 相似文献
89.
Thin films of incompatible polymer blends can form a variety of structures during preparation and subsequent annealing process. For the polymer blend system consisting of polystyrene and poIy(styrene-co-p-bromo-styrene), i.e., PS/PBrxS, its compatibility could be adjusted by varying the degree of bromination and the molecular weight of both components comprised, in this paper, surface chemical compositions of the cast and the annealing films were investigated by X-ray photoelectron spectroscopy (XPS) and contact angle measurement; meanwhile, surface topographical changes are followed by atomic force microscopy (AFM). In addition, substantial attention was paid to the effect of annealing on the morphologic variations induced by phase separation and/or dewetting of the thin film. Moreover, the influences of the molecular weight, Aw, as well as the brominated degree, x%, on the sample surface are explored systematically, and the corresponding observations are explained in virtue of the Flory-Huggins theory, along with the dewetting of the polymer thin film. 相似文献
90.
A new chelating polymer support has been prepared by suspension copolymeriz a tion of synthesized N,N'-bis(3-allyl salicylidene)ethylenediamine monomer Schiff base (N,N'-BSEDA) with styrene (St) and divinylbenzene (DVB) using azobisisobutyronitrile (AIBN) as initiator in the presence of poly(vinyl alcohol). The content and complexation ability of monomer Schiff base (N,N'-BSEDA) for cobalt(II) ions in prepared crosslinked polymer beads have shown dependence on the amount of DVB used in reaction mixture. The amount of monomer Schiff base (N,N'-BSEDA) in crosslinked beads showed a substantial decreasing trend at high concentration of DVB in the reaction mixture (> 1.5 mol dm-3), hence the efficiency of complexation (EC%) and cobalt(II) ion loading (EL%) of polymer beads showed a decreasing trend. The structure of monomer Schiff base (N,N'-BSEDA) and its cobalt(II) complex on polymer support was elucidated by IR, UV and magnetic measurements. The catalytic activity of polymer bound cobalt(Ⅱ) Schiff base complex was evaluated by analyzing kinetic data of decomposition of hydrogen peroxide in the presence of either supported cobalt (II) complex or free cobalt(II) complex. The activation energy for the decomposition of hydrogen peroxide by polymer supported cobalt(II)complex was found to be low (33.37 kJ mol-l) in comparison with unsupported cobalt(II) complex (56.35 kJ mol-1). On the basis of experimental observations, reaction steps are proposed and a suitable rate expression derived. 相似文献