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排序方式: 共有718条查询结果,搜索用时 15 毫秒
1.
《Current Applied Physics》2015,15(11):1296-1302
One-dimensional ZnO materials have been promising for field-emission (FE) application, but how to facially control the alignment of ZnO emitters is still a great challenge especially for patterned display application. Here, we report the fabrication of novel ZnO nanowire (NW) line and bundle arrays for patterned field-electron emitters. The effects of PS template size and heating time on the resulted ZnO nanoarrays were systematically studied. The deformation degree of PS templates was controlled and hence utilized to adjust the alignment of electrochemically deposited ZnO arrays. It was found that the length of NW lines and the density of NW bundles can effectively tuned by the PS template heating time. The optimal FE performance with turn-on electric field as low as of 4.4 V μm−1 and the field-enhancement factor as high as of 1450 were achieved through decreasing the screening effect among the patterned field-electron emitters. 相似文献
2.
HIRONOBU Ishihara 《Geometriae Dedicata》1997,67(3):309-336
Several classification results for ample vector bundles of rank 2 on Hirzebruch surfaces, and on Del Pezzo surfaces, are obtained. In particular, we classify rank 2 ample vector bundles with c2 less than seven on Hirzebruch surfaces, and with c2 less than four on Del Pezzo surfaces. 相似文献
3.
A new unified electroweak model is proposed in this paper. In this unified electroweak model, Higgsmechanism is not used, so no Higgs particle exists in the model. In order to keep the masses of intermediate gaugebosons non-zero, two sets of gauge fields will be introduced. In order to introduce symmetry breaking and to help tointroduce the masses of all fields, a vacuum potential is needed. Except for those terms concerning Higgs particle, thefundamental dynamical properties of this model are similar to those of the standard model. And in a proper limit, thismodel will approximately return to the standard model. The purpose of this paper is not to say that the Higgs particledoes not exist in Nature, it is only to prove that, without a Higgs particle, we can also set up a unified electroweak modelwhich is consistent with present experiments. 相似文献
4.
YANG Wei-Min 《理论物理通讯》2003,40(7)
In the minimal supersymmetric standard model (MSSM) with CP violating phases, this paper discussesthe production of the lightest neutral Higgs boson in association with tau sleptons at future high-energy e e- linearcolliders. In parameter space of the constrained MSSM, the production cross section of e e- → h0τ1 τ1- can be verysubstantial at high energies. This process would provide a production mechanism for probing couplings of neutral Higgsbosons to tau sleptons as well as some soft supersymmetric breaking parameters at next linear colliders. 相似文献
5.
We study the geometry of determinant line bundles associated with Dirac operators on compact odd-dimensional manifolds. Physically, these arise as (local) vacuum line bundles in quantum gauge theory. We give a simplified derivation of the commutator anomaly formula using a construction based on noncyclic trace extensions and associated nonmultiplicative renormalized determinants. 相似文献
6.
In this paper, we study the linearization of the Cauchy problem and the mixed problem for the system of Grad--Hermite moments in nonequilibrium thermodynamics in the neighborhood of the equilibrium state. Stability conditions for solutions of the Cauchy problem are proved as a generalization of the classical Hermite--Biller theorem on stable polynomials. For the mixed problem, we prove an analog of the Vishik--Lyusternik theorem on small singular perturbations of general elliptic problems. The last observation allows us to introduce the Shapiro--Lopatinskii condition, which implies the well-posedness of the mixed problem. 相似文献
7.
Lisa F. Shatz 《国际流体数值方法杂志》2004,44(2):147-174
The indirect boundary element method was used to study the hydrodynamics of oscillatory viscous flow over prolate and oblate spheroids, and over hemispheroidal bodies hinged to a plate. Analytic techniques, such as spheroidal coordinates, method of images, and series representations, were used to make the numerical methods more efficient. A novel method for computing the hydrodynamic torque was used, since for oscillatory flow the torque cannot be computed directly from the weightings. Instead, a Green's function for torque was derived to compute the torque indirectly from the weightings. For full spheroids, the method was checked by comparing the results to exact solutions at low and high frequencies, and to results computed using the singularity method. For hemispheroids hinged to a plate, the method for low frequencies was checked by comparing the results to previous results, and to exact solutions at high frequencies. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
8.
I start with a brief introduction to Higgs mechanism and supersymmetry. Then I discuss the theoretical expectations, current
limits and search strategies for Higgs boson(s) at LHC — first in the SM and then in the MSSM. Finally I discuss the signatures
and search strategies for the superparticles. 相似文献
9.
Hopf Modules and Noncommutative Differential Geometry 总被引:1,自引:0,他引:1
We define a new algebra of noncommutative differential forms for any Hopf algebra with an invertible antipode. We prove that there is a one-to-one correspondence between anti-Yetter–Drinfeld modules, which serve as coefficients for the Hopf cyclic (co)homology, and modules which admit a flat connection with respect to our differential calculus. Thus, we show that these coefficient modules can be regarded as “flat bundles” in the sense of Connes’ noncommutative differential geometry. 相似文献
10.
S. Banerjee 《Pramana》1998,51(1-2):77-86
We summarize here the recent results from the four experiments at the large electron positron collider (LEP). These experiments
provide precise measurements of theW and Z boson properties and their couplings to leptons and quarks. These measurements, together with measurements of the top
quark andW boson masses in the Tevatron collider provide a stringent test of the standard electroweak theory. Searches for Higgs boson
and supersymmetric particles have yielded null results so far giving rise to lower bounds in the parameter space. 相似文献