Heat transfer in composite materials with Stefan–Boltzmann interface conditions

In this paper, we discuss nonstationary heat transfer problems in composite materials. This problem can be formulated as the parabolic equation with Stefan–Boltzmann interface conditions. It is proved that there exists a unique global classical solution to one‐dimensional problems. Moreover, we propose a numerical algorithm by the finite difference method for this nonlinear transmission problem. Copyright © 2007 John Wiley & Sons, Ltd.     

Regioselective ring opening of unsymmetrical cyclic ethers with the A1C13-NaI-acetonitrile system: Application to hydroxylation of ent-kaurene.

Unsymmetrically substituted 5-membered cyclic ethers were effectively cleaved with the A1C1₃-NaI-CH₃CN system at the less hindered carbon atom to afford δ-iodoalcohols. Conversion of ent-kaurene to ent-14α- and ent-12β-hydroxykaurene was achieved through the ring opening of the cyclic ether with the present system as a key step.     

A 128 × 128 Pixel Complementary Metal Oxide Semiconductor Image Sensor with an Improved Pixel Architecture for Detecting Modulated Light Signals

A complementary metal oxide semiconductor (CMOS) image sensor for the detection of modulated light under background illumination has been developed. When an object is illuminated by a modulated light source under background illumination the sensor enables the object alone to be captured. This paper describes improvements in pixel architecture for reducing fixed pattern noise (FPN) and improving the sensitivity of the image sensor. The improved 128 × 128 pixel CMOS image sensor with a column parallel analog-to-digital converter (ADC) circuit was fabricated using 0.35-mm CMOS technology. The resulting captured images are shown and the properties of improved pixel architecture are described. The image sensor has FPN of 1/28 that of the previous image sensor and an improved pixel architecture comprising a common in-pixel amp and a correlated double sampling (CDS) circuit. The use of a split photogate increases the sensitivity of the image sensor to 1.3 times that of the previous image sensor.     

Synthesis of silicon-functionalized 7-silanorbornadienes and their thermolysis and photolysis

A series of 7-silanorbornadienes were prepared and characterized by X-ray crystallographic analysis. 2,3-Benzo-7-mesityl-1,4,5,6-tetraphenyl-7-silanorbornadiene (1a) was prepared by the [4+2] cycloaddition reaction of 1-mesityl-2,3,4,5-tetraphenyl-1-sila-2,4-cyclopentadiene (4) with benzyne. 7-Hydro 1a was converted into 7-chloro-substituted silanorbornadiene 1b. Treatment of 1b with lithium phenylamide and lithium phenylthiolate gave 7-phenylamino-substituted silanorbornadiene 1c and 7-phenylthio-substituted silanorbornadiene 1d, respectively. Reductive lithiation of 1b with lithium naphthalenide afforded 7-lithiated silanorbornadiene 1f, which reacted with chlorotrimethylsilane to give 7-trimethylsilyl-substituted silanorbornadiene 1e. Stereochemistry at the bridging silicon during these transformations was determined by X-ray crystallographic analysis. Thermolysis of 1 produced corresponding silylenes 5, which were trapped with triethylsilane to give disilanes 6. Photolysis of 1 except 1c also afforded corresponding silylenes 5. Theoretical calculation of the models of silanorbornadienes was performed at the MP2/6-31+G(d, p) level.     

A Study of the Stereochemical Course of β‐Oxygen Elimination with a Rhodium(I) Complex

The stereochemical course of β‐oxygen elimination of an organorhodium(I) complex was investigated through the Rh‐catalyzed addition of phenylboronic acid to a chiral propargyl acetate to produce an allene. The degree of chirality transfer suggests that the β‐oxygen elimination takes place in both syn and anti modes.     

On the number of Kekulé structures in capped zigzag nanotubes

Two theoretical formulae for the number of Kekulé structures in general capped zigzag nanotubes are established: one of which is by using the techniques of the transfer matrices, the other involves the eigenvalues of the transfer matrix which reveals the asymptotic behaviour of this index. In effective, according to the symmetric aspect of the tubule, the order of the transfer matrix could be notably decreased. As an application, the closed expressions for four types are given out and the relevant numerical results for those of length up to 50 are listed.     

Anisotropic ion conduction in a unique smectic phase of self-assembled amphiphilic ionic liquids

Two types of thermotropic smectic phase and of anisotropic ion conduction were observed in an amphiphilic ionic liquid, N-ethyl-N'-dodecylimidazolium dodecyl sulfonate/lithium tetrafluoroborate mixture.     

Experimental demonstration of quantum source coding

We report an experimental demonstration of Schumacher's quantum noiseless coding theorem. Our experiment employs a sequence of single photons, each of which represents three qubits in terms of eight spatial and polarization modes. We initially prepare each photon in one of a set of eight nonorthogonal code word states corresponding to the value of a block of three binary letters. We use quantum coding to compress this quantum data into a two-qubit quantum channel and then uncompress the two-qubit channel to restore the original data with a fidelity approaching the theoretical limit.     

Generation of entanglement between frequency bands by nonlinear fiber propagation and spectral pulse shaping

A novel fiber-based scheme for generating quadrature entanglement between a specific pair of frequency bands is proposed. The scheme is based on use of a nonlinear fiber, a spectral pulse shaper, and an adaptive feedback loop. It is numerically predicted that at least -5 dB of the quadrature entanglement will be created by preparation of an appropriate initial phase spectrum. Optimal control of the four-wave mixing terms of the Kerr Hamiltonian is crucial for improvement of the entanglement.