Some observations on the differential cross-sections for pp → K−K+

We present Legendre coefficients from fits to the differential cross-sections for $\text{p}\text{p→ K}{}^{\mathrm{?}}\text{K}{}^{\mathrm{+}}$ in the momentum range 0.8 to 2.4 GeV/c. The s-dependence of the cross-sections at small angles is examined for evidence of Reggeized baryon exchange, and a fit made to this channel and backward K⁺p elastic scattering. Comparisons are made with $\text{p}\text{p→ π}{}^{\mathrm{?}}\text{π}{}^{\mathrm{+}}$.     

On Sample Size and Quick Simultaneous Confidence Interval Estimations for Multinomial Proportions

Abstract

Asymptotically, sample proportions from a multinomial distribution converge in distribution to a multivariate normal distribution with a singular negative product correlation structure. Based on this result, we propose a new approach to estimate the sample size requirement for constructing quick simultaneous confidence intervals (QSCI) for multinomial proportions. In addition, this new approach can be used to construct QSCI and provides a statistical justification to the reports of the opinion polling.     

Cellular automaton models of driven diffusive Frenkel-Kontorova-type systems

Three cellular automaton models of increasing complexity are introduced to model driven diffusive systems related to the generalized Frenkel-Kontorova (FK) models recently proposed by Braun et al. [Phys. Rev. E 58, 1311 (1998)]. The models are defined in terms of parallel updating rules. Simulation results are presented for these models. The features are qualitatively similar to those models defined previously in terms of sequentially updating rules. Essential features of the FK model such as phase transitions, jamming due to atoms in the immobile state, and hysteresis in the relationship between the fraction of atoms in the running state and the bias field are captured. Formulating in terms of parallel updating rules has the advantage that the models can be treated analytically by following the time evolution of the occupation on every site of the lattice. Results of this analytical approach are given for the two simpler models. The steady state properties are found by studying the stable fixed points of a closed set of dynamical equations obtained within the approximation of retaining spatial correlations only up to two nearest-neighboring sites. Results are found to be in good agreement with numerical data.     

A simple and highly efficient P,O-type ligand for Suzuki-Miyaura cross-coupling of aryl halides

A simple and efficient hemilabile-type phosphine ligand, found to be highly effective in Suzuki-Miyaura cross-coupling of aryl chlorides with generally low Pd-catalyst loading (0.05%), was prepared in one step based on an economically attractive approach from commercially available benzamide starting material.     

Facile, efficient, and enantiospecific syntheses of 1,1'-N-linked pseudodisaccharides as a new class of glycosidase inhibitors

This article describes an efficient synthesis of a potent trehalase inhibitor, 1,1'-N-linked pseudodisaccharide 1 (consisting of two valienamines), in 14 steps with an overall yield of 12% and a first synthesis of 2 (consisting of two 2-epi-valienamines) in 15 steps with an overall yield of 24% from (-)-quinic acid. The synthesis involves a stereospecific palladium-catalyzed coupling reaction between an allylic amine and an allylic chloride as the crucial step. The acetonide blocking groups were shown to be the best hydroxyl protecting groups, compatible with the palladium-catalyzed allylic amination reaction that afforded high yields of the 1,1'-N-linked pseudodisaccharides with a minimum amount of an elimination diene side product.     

A self-seeded, surfactant-directed hydrothermal growth of single crystalline lithium manganese oxide nanobelts from the commercial bulky particles

Single crystalline lithium manganese oxide nanobelts were obtained through a self-seeded, surfactant-directed growth process from the commercial bulky particles under hydrothermal treatment. A possible mechanism was proposed to explain the growth of the nanobelts. This new process could be extended to prepare other one-dimensional nanomaterials such as Se nanorods, Te nanotubes, and MnO2 nanowires.     

含C16长碳链1，2－邻二萘醌－2－肟钌（Ⅱ）配合物的合成

通过三种构型的1，2－邻二萘醌－2－肟（2－nqo)钌（Ⅱ）羰基配合物trans, cis－（Ru(2-nqo)2(CO)2](1){(trans-NO,cis-O},cis-,trans-[Ru(2-nqo)2(CO)2] (2){cis-NO,trans-O}及cis,-cis-[Ru(2-nqo)2(CO)2](3){(cis-NO,cis-O)}的去羰 基取代反应，合成了含C16长碳链2-nqo钌（Ⅱ）配合物trans-,cis-[Ru(2-nqo)2 (CO)(spy)](4),cis-,trans-(Ru(2-nqo)2(CO)(spy)(5),cis-,cis-[Ru(2-nqo)2 (CO)(spy)](6)及trans-,trans-(Ru(2-nqo)2(spy)2](7){(trans-NO,trans-O)}。 对其进行了红外、紫外－可见质谱及核磁人振测试，并利用^1H-^1H偶合二维核磁 技术对核磁共振峰进行了指认。     

Uniqueness results for some nonlinear initial and boundary value problems

In the first part of this article a uniqueness theorem is presented for nonlinear initial value problems of the type