Transverse plane

About: Transverse plane is a research topic. Over the lifetime, 17069 publications have been published within this topic receiving 194059 citations. The topic is also known as: axial plane.

Potential-well model in acoustic tweezers

Abstract: Standing-wave acoustic tweezers are popularly used for non-invasive and non-contact particle manipulation. Because of their good penetration in biological tissue, they also show promising prospects for in vivo applications. According to the concept of an optical vortex, we propose an acoustics-vortex- based trapping model of acoustic tweezers. A four-element 1-MHz planar transducer was used to generate 1-MHz sine waves at 1 MPa, with adjacent elements being driven with a π/2-rad phase difference. Each element was a square with a side length of 5.08 mm, with kerfs initially set at 0.51 mm. An acoustic vortex constituting the spiral motion of an acoustic wave around the beam axis was created, with an axial null. Applying Gor'kov's theory in the Rayleigh regime yielded the potential energy and radiation force for use in subsequent analysis. In the transverse direction, the vortex structure behaved as a series of potential wells that tended to drive a suspended particle toward the beam axis. They were highly fragmented in the near field that is very close to the transducer where there was spiral interference, and well-constructed in the far field. We found that the significant trapping effect was only present between these two regions in the transverse direction-particles were free to move along the beam axis, and a repulsive force was observed in the outer acoustic vortex. Because the steepness of the potential gradient near an axial null dominates the trapping effect, the far field of the acoustic vortex is inappropriate for trapping. Particles too close to the transducer are not sufficiently trapped because of the fragmented potential pattern. We suggest that the ideal distance from the transducer for trapping particles is in front of one-fourth of the Rayleigh distance, based on the superposition of the wavefronts. The maximum trapping force acting on a 13-μm polystyrene sphere in the produced acoustic vortex was 50.0 pN, and it was possible to trap approximately 106 particles within a plane; the maximum repulsive force was 24.5 pN, and this was reduced to less than 13 pN by smoothing the outer gradient. Most stiff and dense particles can be used in this model. The presence of transverse trapping and the long working distance make the model useful for 2-D manipulation, particularly in in vivo applications. This paper details the trapping properties in the acoustic vortex and describes methods for improving the design of the transducer. The results obtained support the feasibility of the potential-well model of acoustic tweezers.

Soft flexible catheter tip for use in angiography

Abstract: A plurality of regions of a first transverse rigidity are formed in the flexible tip portion (12) of a catheter having a second transverse rigidity along its length which is greater than the first transverse rigidity. The regions of the lesser first transverse rigidity are formed by areas of the catheter tip (12) having an average transverse cross-sectional area less than a transverse cross-sectional area of the remainder of the catheter apparatus. The plurality of first transverse rigidity regions are formed by a respective plurality of circumferential cutout regions (20-30) in the catheter tip (12).

A Study of Transverse Normal Stress Effects on Vibration of Multilayered Plates and Shells

Abstract: This paper evaluates transverse normal stress σzzeffect on vibration of multilayered structures. To this purpose a mixed plate model initially introduced by Toledano and Murakami has been extended to dynamics analysis of double curved shells. These models allow both continuous interlaminar transverse shear and normal stresses as well as the zigzag form of the displacement distribution in the shell thickness directions to be modelled. Governing equations have been derived by employing a Reissner's mixed theorem. Classical models on the basis of standard displacement formulations have been considered for comparison purposes. The evaluations of transverse stress effects have been conducted by comparing constant, linear and higher order distributions of transverse displacement components in the plate thickness directions. Free vibrational response of layered, simply supported plates, cylindrical and spherical shells made of isotropic as well as orthotropic layers has been analyzed. The numerical investigation carried out and comparison with earlier results has concluded that: • 1. The possibility of describing interlaminar continuous transverse normal stress makes the mixed theories more attractive with respect to other available modelling. • 2. Any refinements of classical models are meaningless, unless the effects of interlaminar continuous transverse shear and normal stresses are both taken into account in a multilayered shell theory.

Direct measurement of the transverse velocity of dark spatial solitons

Abstract: We describe the direct experimental measurement of the transverse propagation velocities of dark spatial solitons. Good agreement is obtained from a comparison of the velocities measured experimentally and the velocities predicted by the two-dimensional theory of Zakharov and Shabat [Sov. Phys. JETP 37, 823 (1973)].

Transverse oscillations in slender Ca II H fibrils observed with Sunrise/SuFI

Abstract: We present observations of transverse oscillations in slender Ca II H fibrils (SCFs) in the lower solar chromosphere We use a 1 hr long time series of high- (spatial and temporal-) resolution seeing-free observations in a 011 nm wide passband covering the line core of Ca II H 3969 nm from the second flight of the Sunrise balloon-borne solar observatory The entire field of view, spanning the polarity inversion line of an active region close to the solar disk center, is covered with bright, thin, and very dynamic fine structures Our analysis reveals the prevalence of transverse waves in SCFs with median amplitudes and periods on the order of 24+-08 km/s and 83+-29 s, respectively (with standard deviations given as uncertainties) We find that the transverse waves often propagate along (parts of) the SCFs with median phase speeds of 9+-14 km/s While the propagation is only in one direction along the axis in some of the SCFs, propagating waves in both directions, as well as standing waves are also observed The transverse oscillations are likely Alfvenic and are thought to be representative of magnetohydrodynamic kink waves The wave propagation suggests that the rapid high-frequency transverse waves, often produced in the lower photosphere, can penetrate into the chromosphere with an estimated energy flux of ~ 15 kW/m^2 Characteristics of these waves differ from those reported for other fibrillar structures, which, however, were observed mainly in the upper solar chromosphere