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971.
Dong LiuPeng Yuan Daoyong Tan Hongmei Liu Tong WangMingde Fan Jianxi ZhuHongping He 《Journal of colloid and interface science》2012,388(1):176-184
Hierarchically porous carbons were prepared using a facile preparation method in which diatomite was utilized as both template and catalyst. The porous structures of the carbon products and their formation mechanisms were investigated. The macroporosity and microporosity of the diatomite-templated carbons were derived from replication of diatom shell and structure-reconfiguration of the carbon film, respectively. The macroporosity of carbons was strongly dependent on the original morphology of the diatomite template. The macroporous structure composed of carbon plates connected by the pillar- and tube-like macropores resulted from the replication of the central and edge pores of the diatom shells with disk-shaped morphology, respectively. And another macroporous carbon tubes were also replicated from canoe-shaped diatom shells. The acidity of diatomite dramatically affected the porosity of the carbons, more acid sites of diatomite template resulted in higher surface area and pore volume of the carbon products. The diatomite-templated carbons exhibited higher adsorption capacity for methylene blue than the commercial activated carbon (CAC), although the specific surface area was much smaller than that of CAC, due to the hierarchical porosity of diatomite-templated carbons. And the carbons were readily reclaimed and regenerated. 相似文献
972.
We develop a necessary and sufficient condition for the Bedrosian identity in terms of the boundary values of functions in
the Hardy spaces. This condition allows us to construct a family of functions such that each of which has non-negative instantaneous
frequency and is the product of two functions satisfying the Bedrosian identity. We then provide an efficient way to construct
orthogonal bases of L
2(ℝ) directly from this family. Moreover, the linear span of the constructed basis is norm dense in L
p
(ℝ), 1 < p < ∞. Finally, a concrete example of the constructed basis is presented. 相似文献
973.
974.
Let G be the complexification of the real Lie algebra so(3) and A = C[t1^±1, t2^±1] be the Lau-ent polynomial algebra with commuting variables. Let L:(t1, t2, 1) = G c .A be the twisted multi-loop Lie algebra. Recently we have studied the universal central extension, derivations and its vertex operator representations. In the present paper we study the automorphism group and bosonic representations ofL(t1, t2, 1). 相似文献
975.
Vo Van Tan 《Bulletin of the Brazilian Mathematical Society》2010,41(3):355-387
Let M be a minimal compact surface, let Γ ⊂ M be a compact analytic sub-variety. Assume that X:= M \ Γ is Stein. Then we will show that X admits algebraic compactifications M
i
(resp. non algebraic compactifications $
\mathbb{M}_i
$
\mathbb{M}_i
) which are not birationally equivalent (resp. not bimeromorphically equivalent) iff X is biholomorphic to
相似文献
976.
The main aim of this paper is to study the stability of the stochastic functional differential equations with infinite delay.
We establish several Razumikhin-type theorems on the exponential stability for stochastic functional differential equations
with infinite delay. By applying these results to stochastic differential equations with distributed delay, we obtain some
sufficient conditions for both pth moment and almost surely exponentially stable. Finally, some examples are presented to illustrate our theory. 相似文献
977.
In this paper, we are concerned with the global existence and convergence rates of the smooth solutions for the compressible magnetohydrodynamic equations in R3. We prove the global existence of the smooth solutions by the standard energy method under the condition that the initial data are close to the constant equilibrium state in H3-framework. Moreover, if additionally the initial data belong to Lp with , the optimal convergence rates of the solutions in Lq-norm with 2≤q≤6 and its spatial derivatives in L2-norm are obtained. 相似文献
978.
Süleyman Demir Murat Tanışlı Mustafa Emre Kansu 《International Journal of Theoretical Physics》2013,52(10):3696-3711
The close analogy between electromagnetic theory and linear gravity is discussed by the hyperbolic (split) octonion formalism. Using the similarities between the relevant field equations of massive dyons in electromagnetic theory and gravito-dyons in linear gravity, a new mathematical model is proposed to formulate these fields in a compact and simple form. The generalized wave equation including both massive dyon and monopole terms is derived. Similarly, the most generalized form of hyperbolic octonionic Klein–Gordon equation is obtained for the hypothetical particle carrying simultaneously both electromagnetic and gravitational charges (masses). 相似文献
979.
Wei Gao Xiao-Dong Tan Ming-Feng Wang Yi-Zhuang Zheng 《International Journal of Theoretical Physics》2013,52(6):2092-2098
We propose an efficient quantum memory scheme with natural inhomogeneous broadening in an asymmetric optical cavity. The scheme uses the strong rephasing pulses like traditional photon echo techniques rather than spectral holeburning, which enables us to have the potential implementation in a much broader range of material systems. In the condition of impedance matching to an optical cavity, we find that the input light pulse can be completely absorbed by an atomic ensemble. We also show that the quantum memory efficiency can be equal to unity even for a small optical depth of the atomic system. 相似文献
980.