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It is shown that the empirical pseudo-second order kinetic equation is a very efficient formula to correlate the kinetic data
generated by applying theoretical expressions developed from the fundamental SRT (Statistical Rate Theory) approach to the
interfacial transport. This is especially true when the most popular linear representation is used in which time/adsorbed
amount is plotted vs. time. However, the commonly observed goodness of such linear plots does not necessarily speak for the
applicability of the pseudo-second order kinetic equation. A reliable estimation, for instance, of the equilibrium adsorbed
amount is possible only when a substantial part of a kinetic isotherms corresponds to the conditions close to equilibrium.
Energetic surface heterogeneity increases the goodness of these linear regressions. Then, experimental errors have only little
effect on the pseudo-second linear plots.
This article is dedicated to Professor Mietek Jaroniec on the occasion of his 60th birthday. 相似文献
114.
It is shown that the set of all multi-homography matrices describing I-element families of interdependent homographies between two views has dimension 4I + 7. 相似文献
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Three types of cross-linked porous organic polymers (either oxygen-, nitrogen-, or sulfur-doped) were carbonized under a chlorine atmosphere to obtain chars in the form of microporous heteroatom-doped carbons. The studied organic polymers constitute thermosetting resins obtained via sol-gel polycondensation of resorcinol and five-membered heterocyclic aldehydes (either furan, pyrrole, or thiophene). Carbonization under highly oxidative chlorine (concentrated and diluted Cl2 atmosphere) was compared with pyrolysis under an inert helium atmosphere. All pyrolyzed samples were additionally annealed under NH3. The influence of pyrolysis and additional annealing conditions on the carbon materials’ porosity and chemical composition was elucidated. 相似文献
120.
This paper deals with a class of controlled mechanical systems in which the number of control inputs, equal to the number
of desired system outputs, is smaller than the number of degrees of freedom. The related inverse dynamics control problem,
i.e., the determination of control input strategy that force the underactuated system to complete the partly specified motion,
is a challenging task. In the present formulation, the desired system outputs, expressed in terms of the system states, are
treated as servo-constraints on the system, and the problem is viewed from the constrained motion perspective. Mixed orthogonal-tangent
realization of the constraints by the available control reactions is stated, and a specialized methodology for solving the
“singular” control problem is developed. The governing equations are manipulated to index three differential-algebraic equations,
and a simple numerical code for solving the equations is proposed. The feedforward control law obtained as a solution to these
equations can then be enhanced by a closed-loop control strategy with feedback of the actual servo-constraint violations to
provide stable tracking of the reference motion in the presence of perturbations and modeling uncertainties. An overhead trolley
crane executing a load-prescribed motion serves as an illustration. Some results of numerical simulations are reported. 相似文献