Numerical-perturbation analysis of edge effect in bending laminated plate

In this paper, we consider a bending laminated plate. At first, the dimensionless variables are used to transform the equilibrium equations of any layer to perturbation differential equations. Secondly, the composite expansion is used and the solution domain is divided into interior and boundary layer regions and the mathematical models for the outer solution and the inner solution are yielded respectively. Then, the inner solution is expressed with the boundary intergral equation.Project Supported by the National Science Foundation of China.     

Numerical analysis of a mixed finite element method for a flow-transport problem

We consider a generic flow-transport system of partial differential equations, which has wide application in the waste disposal industry. The approximation of this system, using a finite element method for the brine, radionuclides, and heat combined with a mixed finite element method for the pressure and velocity, is analyzed. Optimal order error estimates in H¹ and L² are derived. The error analysis is given with no restriction on the diffusion tensor. That is, we have included the effects of molecular diffusion and dispersion. © 1996 John Wiley & Sons, Inc.     

Improvement of M-plane GaN thin film grown on pre-annealing β-LiGaO2 (100) substrate

In this paper, we report the growth of M-plane GaN thin films on LiGaO₂ (100) substrates pre-annealed in vacuum and in air ambient. The surface of M-plane GaN film grown on the LiGaO₂ (100) substrate pre-annealed in air ambient was significantly improved. X-ray diffraction data showed that the M-plane GaN thin film grown on the LiGaO₂ (100) substrate pre-annealed in air ambient has better crystal quality than that grown on the LiGaO₂ (100) substrate pre-annealed in vacuum. In addition, the strain generated between GaN thin film and LiGaO₂ substrate was relaxed when the GaN thin film grew on the LiGaO₂ substrate pre-annealed in air ambient. It revealed that the thermal annealing LiGaO₂ substrate in air ambient can suppress the formation of lithium-rich surface effectively, and then one can grow a high quality M-plane GaN thin film on the LiGaO₂ substrate.     

Synthetic Applications of 3‐(Phenylsulfinyl)‐3‐sulfolene

The title compound 2 was readily prepared by MCPBA oxidation of the sulfide 1. Thermal desulfonylation of 2 gave the sulfoxide‐substituted diene 3. The Diels‐Alder reactions of 3 with various dienophiles gave the cyclized products 4‐9 in good yields. The regiochemistry was found to be dominated by the phenylsulfinyl group, but could be reversed by the presence of a Lewis acid. Deprotonation of 2 by BuLi, followed by the reaction with alkyl halides, gave the substituted 2‐sulfolenes 10. A synthetic application of 10 was demonstrated by converting 10e to the bicyclic product 11.     

Experimental Study of Red-, Green-, and Blue-Based Light Emitting Diodes Visible Light Communications for Micro-Projector Application

In this research, an experimental short-range visible light communication link using red-, green-, and blue-based light-emitting diodes (LEDs) for portable micro-projector applications is presented. A Reconfigurable design of a post-equalizer aimed to improve the inherent narrow modulation bandwidth of red-, green-, and blue-based LEDs has been experimentally implemented, and its effectiveness with optical filters at the receiver is investigated. Reflective liquid-crystal-on-silicon-based micro-projection architecture, widely used in portable micro-projectors, was set up to evaluate the proposed visible light communication system. The measurement results demonstrated that a significant aggregative bandwidth improvement of 162 MHz as well as an aggregative data transmission rate of nearly 400 Mb/s can be achieved by using a non-return-to-zero–on-off keying (NRZ–OOK) modulation scheme based on only one polarization state of incident light without any offline signal processing.     

Using a Multi‐Shelled Hollow Metal–Organic Framework as a Host to Switch the Guest‐to‐Host and Guest‐to‐Guest Interactions

A bio‐inspired design of using metal–organic framework (MOF) microcrystals with well‐defined multi‐shelled hollow structures was used as a matrix to host multiple guests including molecules and nanoparticles at separated locations to form a hierarchical material, mimicking biological structures. The interactions such as energy transfer (ET) between different guests are regulated by precisely fixing them in the MOF shells or encapsulating them in the cavities between the MOF shells. The proof‐of‐concept design is demonstrated by hosting chromophore molecules including rhodamine 6G (R6G) and 7‐amino‐4‐(trifluoromethyl)coumarin (C‐151), as well as metal nanoparticles (Pd NPs) into the multi‐shelled hollow zeolitic imidazolate framework‐8 (ZIF‐8). We could selectively establish or diminish the guest‐to‐framework and guest‐to‐guest ET. This work provides a platform to construct complex multifunctional materials, especially those need precise separation control of multi‐components.     

Electrophoresis of a concentrated dispersion of spherical particles covered by an ion-penetrable membrane layer

The electrophoretic behavior of a concentrated dispersion of soft spherical particles is investigated theoretically, taking the effects of double-layer overlapping and double-layer polarization into account. Here, a particle comprises a rigid core and an ion-penetrable layer containing fixed charge, which mimics biocolloids and particles covered by artificial membrane layers. A cell model is adopted to simulate the system under consideration, and a pseudo-spectral method based on Chebyshev polynomials is chosen for the resolution of the governing electrokinetic equations. The influence of the key parameters, including the thickness of the double layer, the concentration of particles, the surface potential of the rigid core of a particle, and the thickness, the amount of fixed charge, and the friction coefficient of the membrane layer of a particle on the electrophoretic behavior of the system under consideration is discussed. We show that while the result for the case of a dispersion containing rigid particles can be recovered as the limiting case of a dispersion containing soft particles, qualitative behaviors that are not present in the former are observed in the latter.     

Electrocatalytic reductions of nitrite, nitric oxide, and nitrous oxide by thermophilic cytochrome P450 CYP119 in film-modified electrodes and an analytical comparison of its catalytic activities with myoglobin

Previous investigations of nitrite and nitric oxide reduction by myoglobin in surfactant film modified electrodes characterized several distinct steps in the denitrification pathway, including isolation of a nitroxyl adduct similar to that proposed in the P450nor catalytic cycle. To investigate the effect of the axial ligand on these biomimetic reductions, we report here a comparison of the electrocatalytic activity of myoglobin (Mb) with a thermophilic cytochrome P450 CYP119. Electrocatalytic nitrite reduction by CYP119 is very similar to that by Mb: two catalytic waves at analogous potentials are observed, the first corresponding to the reduction of nitric oxide, the second to the production of ammonia. CYP119 is a much more selective catalyst, giving almost exclusively ammonia during the initial half-hour of reductive electrolysis of nitrite. More careful investigations of specific steps in the catalytic cycle show comparable rates of nitrite dehydration and almost identical potentials and lifetimes for ferrous nitroxyl intermediate (Fe(II)-NO(-)) in CYP119 and Mb. The catalytic efficiency of nitric oxide reduction is reduced for CYP119 as compared to Mb, attributable to both a lower affinity of the protein for NO and a decreased rate of N-N coupling. Isotopic labeling studies show ammonia incorporation into nitrous oxide produced during nitrite reduction, as has been termed co-denitrification for certain bacterial and fungal nitrite reductases. Mb has a much higher co-denitrification activity than CYP119. Conversely, CYP119 is shown to be slightly more efficient at the two-electron reduction of N(2)O to N(2). These results suggest that thiolate ligation does not significantly alter the catalytic reactivity, but the dramatic difference in product distribution may suggest an important role for protein stability in the selectivity of biocatalysts.