Strong decays of the newly observed D(2550)D(2550), D(2600)D(2600), D(2750)D(2750), and D(2760)D(2760)

The strong decay properties of the newly observed $D(2550)$, $D(2600)$, $D(2750)$ and $D(2760)$ are studied in a constituent quark model. It is predicted that the $D(2760)$ and $D(2750)$ seem to be two overlapping resonances. The $D(2760)$ could be identified as the $1^3D_3$ with $J^P=3^-$, while the $D(2750)$ is most likely to be the high-mass mixed state $|1{D_2}'>_H$ ($J^P=2^-$) via the $1^1D_2$-$1^3D_2$ mixing. The $D(2600)$ favors the low-mass mixed state $|(SD)_1>_L$ $(J^P=1^-)$ via the $1^3D_1$-$2^3S_1$ mixing. The $D(2550)$ as the $2^1S_0$ assignment bears controversies for its too broad width given in experiments.Comment: 8 pages, 5 figures; The review of the model is added. Some discussion of the $D(2750)$ is include

A flexible and adaptive Simpler GMRES with deflated restarting for shifted linear systems

In this paper, two efficient iterative algorithms based on the simpler GMRES method are proposed for solving shifted linear systems. To make full use of the shifted structure, the proposed algorithms utilizing the deflated restarting strategy and flexible preconditioning can significantly reduce the number of matrix-vector products and the elapsed CPU time. Numerical experiments are reported to illustrate the performance and effectiveness of the proposed algorithms.Comment: 17 pages. 9 Tables, 1 figure; Newly update: add some new numerical results and correct some typos and syntax error

Quantitative measurement of pyrolysis and combustion species concentration by molecular-beam-sampling-mass-spectrometry

A molecular-beam-sampling apparatus utilizing both a time-of-flight mass spectrometer with vacuum ultraviolet (VUV) photoionization and a quadrupole mass spectrometer with electron impact ionization is described. These systems are used to analyze reactants and products, as well as reactive intermediates, from flow tube experiments at reduced pressures and elevated temperatures. It is shown that the quadrupole signal sensitivity can be predicted using literature cross sections which are based upon the atom hybridization within the various molecules. Measurements of the VUV photoionization sensitivity for stable species led to development of a group additivity approach to predict cross sections. This approach was extended to reactive intermediates, and detailed comparisons of quadrupole and TOF data shows a very good agreement between the two techniques. The two techniques are compensation of each other and provide the full information we need. It is also shown how the minimal fragmentation achieved with the VUV source leads to much more accurate species concentration measurements for reactive intermediates

A comparative study of war metaphors in English and Chinese business media discourse

Journalistic business discourse plays an indispensable role in people’s lives. It serves not only to inform the public about ongoing business activities and economic processes, but also influence the public in their strategic decision-making about investment options. Metaphor is a tool employed to help fulfill the communicative and persuasive functions of the popular business discourse, which is the target of this study. Based on two self-compiled corpora of business news articles in English and Chinese, the study laid particular emphasis on the conceptual metaphor of BUSINESS IS WAR and showed that though the use of this conceptual metaphor was common in business discourse across the two languages, obvious differences in terms of the metaphorical lexis’ frequency of occurrence, their specific collocations and unconventional referents were noted. The conceptual metaphor BUSINESS IS WAR was subdivided into more detailed conceptual metaphors based on the subdivision of the domain of war and the mappings and impositions between the subfields of the domain of war and business were analyzed. The two language cultures agree that they have the same origin for human warfare, but they have developed their concept of war under the influence of their own experience. The analysis of the war metaphors in sample English and Chinese news articles demonstrates its emotion evoking functionto convey evaluative judgments and achieve persuasive ends, and the ideological function to construct reality as a means of maintaining or challenging power relations

The K−p→Σ0π0K^-p\to \Sigma^0\pi^0 reaction at low energies in a chiral quark model

A chiral quark-model approach is extended to the study of the $\bar{K}N$ scattering at low energies. The process of $K^-p\to \Sigma^0\pi^0$ at $P_K\lesssim 800$ MeV/c (i.e. the center mass energy $W\lesssim 1.7$ GeV) is investigated. This approach is successful in describing the differential cross sections and total cross section with the roles of the low-lying $\Lambda$ resonances in $n=1$ shells clarified. The $\Lambda(1405)S_{01}$ dominates the reactions over the energy region considered here. Around $P_K\simeq 400$ MeV/c, the $\Lambda(1520)D_{03}$ is responsible for a strong resonant peak in the cross section. The $\Lambda(1670)S_{01}$ has obvious contributions around $P_K=750$ MeV/c, while the contribution of $\Lambda(1690)D_{03}$ is less important in this energy region. The non-resonant background contributions, i.e. $u$-channel and $t$-channel, also play important roles in the explanation of the angular distributions due to amplitude interferences.Comment: 18 pages and 7 figure