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111.
Plasma doping is the candidate for semiconductor doping. Accurate simulation of the doping technology is needed for the advanced integrated circuit manufacturing. In this paper, the plasma doping process simulation is performed by using the localized molecular dynamics method. Models that involve the statistics of the implanted compositions, angles and energies are developed. The effect of the model on simulation results is studied. The simulation results about the doping concentration profile are supported by experimental data. 相似文献
112.
Given a Tychonov space X we can construct another space Y with the same group of homeomorphisms such that X and Y are, in some sense, "almost arbitrarily different". 相似文献
113.
一类非线性m-点边值问题正解的存在性 总被引:26,自引:4,他引:22
设α∈C[0,1],b∈C([0,1],(-∞,0)).设φ(t)为线性边值问题 u″+a(t)u′+b(t)u=0, u′(0)=0,u(1)=1的唯一正解.本文研究非线性二阶常微分方程m-点边值问题 u″+a(t)u′+b(t)u+h(t)f(u)=0, u′(0)=0,u(1)-sum from i=1 to(m-2)((a_i)u(ξ_i))=0正解的存在性.其中ξ_i∈(0,1),a_i∈(0,∞)为满足∑_(i=1)~(m-2)a_iφ_1(ξ_i)<1的常数,i∈{1,…,m-2}.通过运用锥上的不动点定理,在f超线性增长或次线性增长的前提下证明了正解的存在性结果. 相似文献
114.
Min Ru 《Proceedings of the American Mathematical Society》2001,129(5):1263-1269
In this paper, we show that the First Main Theorem in -adic Nevanlinna theory implies the Second Main Theorem without the ramification term.
115.
We study experimentally the interaction of a dark spot with a nonlinear photonic lattice with fully incoherent white light emitted from an incandescent bulb in the self-defocussing photovoltaic media when the dark spot is aimed at different positions of lattices with different lattice spacing. In this case a host of novel phenomena is demonstrated, including dark spot induced lattice dislocation-deformation, the annihilation of the dark spot and so on. Results demonstrate that the interaction between incoherent dark spot and photonic lattice is always attraction and the large-spacing photonic lattice is analogous to the continuous medium. 相似文献
116.
117.
Mesoporous ZrMCM‐41 nanoparticles were synthesized by a usual way where tetraethyl‐orthosilicate (TEOS) and zirconium nitrate were used as the inorganic precursors. The obtained nanoscale ZrMCM‐41 was characterized by X‐ray diffraction, N2 physis‐sorption, scanning electron microscopy and transmission electron microscopy. Characterization results revealed that zirconium salt added in the synthesis had a crucial effect on the assembly of nanoscale ZrMCM‐41 with relatively uniform particle size, which was rarely observed in reported studies for ZrMCM‐41 synthesized using the similar method. Meanwhile, the possible mechanism behind the synthesis was discussed based on the character of hydrolysis and condensation of TEOS and the mild acidic environment induced by the hydrolysable zirconium salt under aqueous conditions. Thus obtained nanoscale ZrMCM‐41 with developed pore structures may be advantageous to general applications in catalysis or adsorption host‐guest chemistry in terms of efficient mass transport of guest molecules. 相似文献
118.
IntroductionWithspecialandnovelstructures,macropolycyclicmoleculespreselltamultitudeofnewproperties'andopenupvastvistasforapplicationsinmanyfields"',suchassupramoleculardevices,luminescentlabels,fluorescentprobesinbiologicalandmedicalapplications,magneticresonanceimagingandcatalyticcleavageofRNA,and.-theyarealsoimportantligands'forrecognizinginorganicandorganiccanons,anionsandneutralmolecules.Becauseofmulti-stepprocessandlowyields',thesynthesisofmacropolycycliccompoundsaresometimesverydifficu… 相似文献
119.
用溶胶 凝胶法合成了Li2 xRExSi1 -xO3(RE =Pr ,Nd ,Sm ,Gd ;x =0~ 0 15 ) ,用DTA TG ,XRD ,TEM及交流阻抗等技术对样品的结构、形貌、粒径及离子导电性等进行了观察和测试。其固溶体形成范围是 0 相似文献
120.