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The length dependence of surface enhanced Raman scattering has been investigated in Copper nanorod array substrates fabricated using an oblique angle deposition technique in this paper. The surface enhanced Raman scattering intensity of trans-l,2-bis(4-pyridyl) ethene was found to be proportional to the length of the nanorod.

We fabricated regular ladder-shaped nanostructures on polystyrene microspheres by oblique angle deposition (OAD) technique. The results show that the nanostructures exhibit chirality and their circular dichroism (CD) signals can be enhanced by adjusting the gradients of the structures or the angles between the steps. Such structures have potential applications in optical devices.

This paper reports that a ladder-shaped chiral nanostructure formed on a glass substrate by oblique angle deposition technique, where hexagonal close-packed (HCP) etched microspheres were removed. The nanostructure exhibits Circular Dichroism (CD). Moreover, the CD of this structure in different local area presents anisotropy, which was investigated both experimentally and theoretically. This chiral nanostructure lay the groundwork for the applications in chiral optical devices.

Micro fluidized bed is a promising reactor for a variety of industrial processes. It is important to understand the hydrodynamics of gas-solid fluidization of the micro fluidized beds with different oblique angles. This study numerically investigated the effects of oblique angle on the fluidization behavior and pressure drop in the micro fluidized beds by Computational Particle-Fluid Dynamics (CPFD) models. The results show that the oblique angle of the bed affects strongly the particles, fluidized gas and pressure distribution in the micro fluidized bed due to strong wall effects. The bed with oblique angle of 0° can achieve better gas-solid contact than the inclined beds. The pressure drops in the micro fluidized beds decrease linearly with increasing oblique angles of the beds when the oblique angles are beyond 15°. The oblique angle of the bed has a great influence on the fluidization behavior and pressure drop in the micro fluidized bed.

This work presents an innovative design for a flow-through dielectrophoretic cell sorting based on silicon bulk microelectrodes featuring sidewall undercuts. The microelectrodes are configured into an interdigitated array with digits extending across the flow chamber at an oblique angle against the flow stream. Target cells under dielectrophoretic forces and hydrodynamic drag can slide along the digits to a dedicated outlet. The design has been showcased for continuous-flow sorting of viable and non-viable mammalian cells, achieving a throughput of 16,600 cells/min, an order of magnitude higher than those reported for existing continuous-flow cell sorting designs using thin-film or volumetric microelectrodes.

Metamaterial emitters have previously been studied for controlling the angle and polarization of near-IR emissivity from a surface. Here, we investigate bianisotropic metamaterials that can be tailored to have custom angle-dependent emissivity polarization profiles in the near-IR. A genetic algorithm is employed to synthesize an electromagnetic band-gap metamaterial structure that transitions from linear polarization normal to the surface to circular polarization at a preselected oblique angle.

Soil roughness parameters have been traditionally retrieved using altimetric profiles acquired from profilometer devices. Measuring soil roughness using the technology called Terrestrial Laser Scanner (TLS) is an innovative method because of it is possible to get a three-dimensional surface more realistic than previous approaches. This paper shows a comparison between both techniques for different kind of soil roughness. A multilateral-based acquisition is proposed for TLS measurement. Analyses are made with profiles from the same soil samples acquired using a profilometer and a TLS. Profile-to-profile comparison got altimetric correlation between both devices and how soil roughness parameters are affected with. Results offer a straight relation (R=0.92 globlally) between both datasets. The oblique angle used by multilateral acquisition in TLS reports a smoother value than vertical acquisition by profilometer

A few problems are discussed in transmittance measurements at an oblique angle of incidence. Incident angle dependence on transmittance of a 10mm thick sample of silicon dioxide was measured by four kinds of experimental setups. Each measured transmittance was compared with theoretical one. The most reliable means of solving is that beams are directed to a detector by automatic adjusting of an angle of a mirror between the sample and the detector. This idea has been realized in a STAR GEM device.

A new magnetostrictive patch array transducer for the generation and measurement of torsional waves was developed for the on-line health monitoring of rotating shafts. Even though the torsional wave is useful in nondestructive evaluation due to its non-dispersive property, a transducer generating torsional waves in rotating shafts has not been developed so far. This report is concerned with torsional wave transduction experiments performed with an array of magnetostrictive patches bonded on rotating shafts. By bonding an array of magnetostrictive rectangular patches on the outer surface of the shaft at an oblique angle of 45deg and encircling the array by a solenoid coil, torsional waves were generated and measured successfully. Several experiments were carried out to check the transducer performance. After confirming the performance, the transducer was applied to the detection of damage in a rotating shaft.

Arrays can be defined by an electrode pattern on the surface of a 1-3 piezocomposite substrate, but spurious modes arise when the array electrodes are aligned with the rows of pillars. One method that is used to suppress these spurious modes is to pattern array elements at an oblique angle to the rows of pillars in the piezocomposite. In this paper we confirm theoretically that rotating the array improves performance using the PZFlex finite element analysis package. Compared to the case with aligned electrodes, rotating the array electrodes suppresses spurious modes by disrupting the periodicity of the piezocomposite along the array azimuth and therefore waves that propagate along the array. However, spurious modes can still arise due to the periodicity imposed on the structure by the pattern of array electrodes. Rotating the electrodes also ensures that all elements in the array have similar performance characteristics.

Split ring resonator arrays have been fabricated to demonstrate magnetic resonance in the terahertz regime. Spectroscopic transmission measurements as a function of oblique angle enable quantitative values of the permeability to be calculated

Figure 1. This overview image displays the 3D streamlines representing the DTI tracks, several functional areas, the vasculature and the underlying anatomy clipped at an oblique angle. The focus of this poster is the addition of the track geometry to an existing fMRI visualization application. On the right we can see the cortical spinal track (cyan) projecting from the left hand motor region (green).

The frequency response of a bandstop square-loop frequency selective (FS) structure illuminated at an oblique angle can be accurately predicted using a simple equivalent circuit model. A frequency selective plasterboard wall was constructed and measured to reveal a downwards change in resonant frequency (with at least 30 dB attenuation) from 9.2 GHz at an incident angle of 0/spl deg/ (normal) to 8.5 GHz at 45/spl deg/ incidence. The equivalent circuit model predictions align well with measurements. The model allows the rapid prediction of FS surface response and aids the design of FS structures that have desirable (less angle-dependent) characteristics.

In this paper, a 3D FEA model is proposed to study the obliquely oriented piezocomposite array, where the transducer is formed of it 2-2 composite material in which the pattern of the composite material is oriented at an oblique angle to the elevation axis of the transducer array elements. Such obliquely oriented piezocomposite, as stated in US Patent 6,104,126, offers additional benefits such as easier in-process dimension registration, mechanical flexibility, and performance improvement by strongly suppressing the lateral resonance modes when compared with the conventional 2-2 composite with parallel or orthogonal orientation. A 3D FEA model using the commercially available PZFlex package has been developed to simulate the obliquely oriented piezocomposite material and transducer array. Experimental data from obliquely oriented piezocomposite materials of different orientation angles have been taken and compared with the model predictions. The 3D FEA modeling results showed very good agreement with the experimental data.

The authors analyse the packaging and metallisation effects of a valley microstrip line with a slit applied to practical circuits. The analysis is based on the finite difference method in conjunction with the higher order asymptotic boundary condition. The results presented here have the following interesting features: The higher order asymptotic boundary condition can put the outer boundary much closer to the centre of a valley microstrip line. As a result, much less computational effort needs to be made for accurate performance prediction; when a shielding metal box, if any, is 2-3 times the thickness of the dielectric film, the packaging effect is appreciable; for a dielectric film of micrometre order, the metallisation thickness of the valley strip and the slit ground metal have significant influence on the characteristic parameters; and the characteristic impedance and the effective dielectric constant can be adjusted by changing the oblique angle and the slit width.