Determining the chirality of Yukawa couplings via single charged Higgs boson production in polarized photon collisions

When the charged Higgs boson is too heavy to be produced in pairs, the predominant production mechanism at linear colliders is via the single charged Higgs boson production processes, such as e(-)e(+)-->bcH+,taunuH+ and gammagamma-->bcH+,taunuH+. We show that the yield of a heavy charged Higgs boson at a gammagamma collider is typically 1 or 2 orders of magnitude larger than that at an e(-)e(+) collider. Furthermore, a polarized gammagamma collider can determine the chirality of the Yukawa couplings of fermions with charged Higgs boson via single charged Higgs boson production and, thus, discriminate models of new physics.     

取代苯甲醛-N-芳氧乙酰腙类化合物的合成与表征

利用取代苯甲醛与芳氧基乙酰肼反应,合成了8个新的芳氧基乙酰脘类化合物,其结构经IR,^1HNMR和元素分析证实。     

Multigraphic Degree Sequences and Hamiltonian-connected Line Graphs

Acta Mathematicae Applicatae Sinica, English Series - Let G be a multigraph. Suppose that e = u1v1 and e′ = u2v2 are two edges of G. If e ≠ e′, then G(e, e′) is the graph...     

Echo-wave scattering characteristics of the diffuse target in the slant atmospheric turbulence

The extended Huygens–Fresnel principle is utilized to make analysis of the received intensity for laser beam propagation through the atmospheric turbulence in the slant path. For a diffuse target, the effects of the turbulence on the statistical parameters such as the mutual coherence function and the mean intensity are studied in detail. The influence of the incident wave radius and the distance of the incident beam on these parameters are discussed.     

On Group Chromatic Number of Graphs

Let G be a graph and A an Abelian group. Denote by F(G, A) the set of all functions from E(G) to A. Denote by D an orientation of E(G). For f ∈ F(G,A), an (A,f)-coloring of G under the orientation D is a function c : V(G)↦A such that for every directed edge uv from u to v, c(u)−c(v) ≠ f(uv). G is A-colorable under the orientation D if for any function f ∈ F(G, A), G has an (A, f)-coloring. It is known that A-colorability is independent of the choice of the orientation. The group chromatic number of a graph G is defined to be the least positive integer m for which G is A-colorable for any Abelian group A of order ≥m, and is denoted by χ_g(G). In this note we will prove the following results. (1) Let H₁ and H₂ be two subgraphs of G such that V(H₁)∩V(H₂)=∅ and V(H₁)∪V(H₂)=V(G). Then χ_g(G)≤min{max{χ_g(H₁), max_v∈V(H2)deg(v,G)+1},max{χ_g(H₂), max_u∈V(H1) deg (u, G) + 1}}. We also show that this bound is best possible. (2) If G is a simple graph without a K_3,3-minor, then χ_g(G)≤5.     

碱处理浓度对预脱铝ZSM-5成孔过程及其MTG反应性能的影响

在80℃水浴条件下,对ZSM-5分子筛进行酸碱处理改性;重点考察了碱处理溶液浓度对酸预处理脱铝后ZSM-5分子筛微观结构及其催化甲醇制汽油(MTG)性能的影响。通过BET、XRD、FT-IR、NH₃-TPD和TEM等手段对样品进行表征。结果表明,单独酸处理没有改变分子筛孔结构,单独碱处理产生了并不明显的介孔。酸预处理后再碱处理可促进介孔的产生,产生更为显著的介孔结构;而且随着碱处理强度的增加,分子筛样品的介孔比表面积比例和孔体积均先增大后降低。酸浓度2 mol·L^-1,碱浓度0.4 mol·L^-1条件处理得到的分子筛,介孔比表面积比例和孔容均达到最大,酸量和酸强度最低。在400℃,0.1 MPa,WHSV=2.1 h^-1条件下,甲醇制汽油反应性能最佳:汽油收率由未改性时的30wt%提高到34wt%,寿命更是由16 h延长到135 h,芳烃含量由原来的73wt%降至20wt%。