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721.
722.
723.
RuCl2(TPPMS)3(DMSO) (complex (I)) is very soluble in the ionic liquid 1-nbutyl-3-methylimidazolium hexafluorophosphate (BMI.PF6). Complex (I) catalyzes 1-hexene hydrogenation (500 psi H2 and 100oC) in a two-phase system, with 80% conversion in 24 h, with little substrate isomerization. Changes in catalytic behavior with temperature, pressure, time and substrate/catalyst relation are presented. Complex (I) shows good stability and can be reused several times with little activity loss. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
724.
We present an unusual case of duplication of the fifth lumbar vertebra and sacrum in a 6-year-old boy. The spinal cord was also duplicated and tethered by bone spurs bilaterally. The imaging features and the embryological basis of diplomyelia are discussed.  相似文献   
725.
726.
If X is a k-dimensional random vector, we denote by X(i) the vector X with coordinate i deleted and by X(i,j) the vector X with coordinates i and j deleted. If for each i the conditional distribution of Xi given X(i) = x(i) is univariate normal for each x(i) K−1 and if for each i, j the conditional distribution of Xi given X(i,j) = x(i,j) is univariate normal for each x(i,j) k−2 then it is shown that X has a classical k-variate normal distribution.  相似文献   
727.
We report results on rho(770)(0)-->pi(+)pi(-) production at midrapidity in p+p and peripheral Au+Au collisions at sqrt[s(NN)]=200 GeV. This is the first direct measurement of rho(770)(0)-->pi(+)pi(-) in heavy-ion collisions. The measured rho(0) peak in the invariant mass distribution is shifted by approximately 40 MeV/c(2) in minimum bias p+p interactions and approximately 70 MeV/c(2) in peripheral Au+Au collisions. The rho(0) mass shift is dependent on transverse momentum and multiplicity. The modification of the rho(0) meson mass, width, and shape due to phase space and dynamical effects are discussed.  相似文献   
728.
This work employs UV-visible extinction spectroscopy as a new spectral mapping technique to characterize self-assembled polystyrene microsphere samples produced by convective self-assembly (CSA). This spectroscopic technique was successfully used to analyze the periodic particle arrays produced by the polystyrene template, yielding a detailed characterization of each sample. The CSA-prepared samples proved to be more uniform across a sample as well as more reproducible than previous sample preparation techniques. For the first time, a detailed characterization and quantitative evaluation of the entire sample has been performed by spectroscopic mapping.  相似文献   
729.
Summary Let M be a number field of degree m with ring of integers \bZ_M. Let F\in\bZ_M[X,Y] be a form of degree n such that F(X,1) has distinct roots. Let\break G\in\bZ[X,Y] be an arbitrary polynomial of degree k. Assuming that k\le n-2m\pl 1 if all roots of F^{(i)}(X,1) (1\le i\le n) are complex and k\le n-4m\pl 1 otherwise, we provide an efficient algorithm for finding all solutions X,Y\in\bZ_M, \max\b(\overline{|X|},\overline{|Y|}\,\b)\ki C of the inequality \overline{\b|F(X,Y)\b|\!}\,\le c \cdot \overline{\b|G(X,Y)\b|\!}\,. We provide numerical examples with m=3 and C=10^{100}.  相似文献   
730.
Charged hadrons in [EQUATION: SEE TEXT] associated with particles of [EQUATION: SEE TEXT] are reconstructed in pp and Au+Au collisions at sqrt[sNN]=200 GeV. The associated multiplicity and p magnitude sum are found to increase from pp to central Au+Au collisions. The associated p distributions, while similar in shape on the nearside, are significantly softened on the awayside in central Au+Au relative to pp and not much harder than that of inclusive hadrons. The results, consistent with jet quenching, suggest that the awayside fragments approach equilibration with the medium traversed.  相似文献   
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