Magnetic penetration depth of YBa2Cu3O(7-delta) thin films determined by the power transmission method

Science.gov (United States)

Heinen, Vernon O.; Miranda, Felix A.; Bhasin, Kul B.

1992-01-01

A power transmission measurement technique was used to determine the magnetic penetration depth (lambda) of YBa2Cu3O(7-delta) superconducting thin films on LaAlO3 within the 26.5 to 40.0 GHz frequency range, and at temperatures from 20 to 300 K. Values of lambda ranging from 1100 to 2500 A were obtained at low temperatures. The anisotropy of lambda was determined from measurements of c-axis and a-axis oriented films. An estimate of the intrinsic value of lambda of 90 +/- 30 nm was obtained from the dependence of lambda on film thickness. The advantage of this technique is that it allows lambda to be determined nondestructively.

Estimation of the frequency and magnetic field dependence of the skin depth in Co-rich magnetic microwires from GMI experiments

Directory of Open Access Journals (Sweden)

Arcady Zhukov

2016-09-01

Full Text Available We studied giant magnetoimpedance (GMI effect in magnetically soft amorphous Co-rich microwires in the extended frequency range. From obtained experimentally dependences of the GMI ratio on magnetic field at different frequencies we estimated the penetration depth and its dependence on applied magnetic field and frequency.

An EPR methodology for measuring the London penetration depth for the ceramic superconductors

Science.gov (United States)

Rakvin, B.; Mahl, T. A.; Dalal, N. S.

1990-01-01

The use is discussed of electron paramagnetic resonance (EPR) as a quick and easily accessible method for measuring the London penetration depth, lambda for the high T(sub c) superconductors. The method utilizes the broadening of the EPR signal, due to the emergence of the magnetic flux lattice, of a free radical adsorbed on the surface of the sample. The second moment, of the EPR signal below T(sub c) is fitted to the Brandt equation for a simple triangular lattice. The precision of this method compares quite favorably with those of the more standard methods such as micro sup(+)SR, Neutron scattering, and magnetic susceptibility.

Muon-spin-rotation measurements of the London penetration depths in YBa2Cu3O6.97

International Nuclear Information System (INIS)

Puempin, B.; Keller, H.; Kuendig, W.; Odermatt, W.; Savic, I.M.; Schneider, J.W.; Simmler, H.; Zimmermann, P.; Kaldis, E.; Rusiecki, S.; Maeno, Y.; Rossel, C.

1990-01-01

Muon-spin-rotation (μSR) experiments on a high-quality sintered YBa 2 Cu 3 O x sample [x=6.970(1)] were performed, in order to obtain an accurate knowledge of the magnitude and the temperature dependence of the magnetic penetration depth in this copper oxide superconductor. Special attention was given to the data analysis. In particular, the systematic errors introduced by different types of analyses were estimated. Our results show that the temperature dependence of the effective penetration depth λ eff into the sintered sample is well described by the two-fluid model, with λ eff (0)=155(10) nm. This behavior of λ eff (T) is consistent with conventional s-wave pairing. With the anisotropy ratio γ=λ c /λ ab =5(1) measured in a previous μSR experiment, the penetration depths λ ab (0)=130(10) nm and λ c (0)=500--800 nm (parallel and perpendicular to the CuO 2 planes, respectively) were extracted. Our results are compared with those obtained by other experimental techniques and theoretical predictions

A theoretical basis of the approach for the magnetic field penetration measurement

International Nuclear Information System (INIS)

Bezotosnyi, P I; Gavrilkin, S Yu; Ivanenko, O M; Mitsen, K V; Tsvetkov, A Yu

2016-01-01

An approach for the assessment of London penetration depth of superconducting films is proposed. This approach is based on the analysis of linear response of the sample to a local low-frequency alternating magnetic field generated by the measuring coil disposed near the film surface. A visual “electrical engineering” model of induced currents distribution in the superconductor taking into account the kinetic inductance was developed for a description of this response. The possibility of determining of the penetration depth from changing the inductance of the system “coil-sample” is shown in the framework of this model. The sensitivity of the proposed method for the films with different thicknesses is considered. (paper)

Influence of the impurities on the depth of penetration with carbon steel weldings

Directory of Open Access Journals (Sweden)

O. Savytsky

2014-04-01

Full Text Available In this paper the results of the research about the influence of the impurities on the depth of penetration with carbon steels weldings of different chemical composition are presented. These data suggest that presence of those impurities, such as sulphure and oxygen, in the steel, increases the depth of penetration to 1,3 - 1,5 times compared to welding refined steels. Applying activating fluxes for welding high tensile steels, provides an increase in the depth of penetration of 2 - 3 times.

Wavelength-dependent penetration depth of near infrared radiation into cartilage.

Science.gov (United States)

Padalkar, M V; Pleshko, N

2015-04-07

Articular cartilage is a hyaline cartilage that lines the subchondral bone in the diarthrodial joints. Near infrared (NIR) spectroscopy is emerging as a nondestructive modality for the evaluation of cartilage pathology; however, studies regarding the depth of penetration of NIR radiation into cartilage are lacking. The average thickness of human cartilage is about 1-3 mm, and it becomes even thinner as OA progresses. To ensure that spectral data collected is restricted to the tissue of interest, i.e. cartilage in this case, and not from the underlying subchondral bone, it is necessary to determine the depth of penetration of NIR radiation in different wavelength (frequency) regions. In the current study, we establish how the depth of penetration varies throughout the NIR frequency range (4000-10 000 cm(-1)). NIR spectra were collected from cartilage samples of different thicknesses (0.5 mm to 5 mm) with and without polystyrene placed underneath. A separate NIR spectrum of polystyrene was collected as a reference. It was found that the depth of penetration varied from ∼1 mm to 2 mm in the 4000-5100 cm(-1) range, ∼3 mm in the 5100-7000 cm(-1) range, and ∼5 mm in the 7000-9000 cm(-1) frequency range. These findings suggest that the best NIR region to evaluate cartilage with no subchondral bone contribution is in the range of 4000-7000 cm(-1).

Measurement of the penetration depth and coherence length of MgB2 in all directions using transmission electron microscopy

DEFF Research Database (Denmark)

Loudon, J. C.; Yazdi, Sadegh; Kasama, Takeshi

2015-01-01

We demonstrate that images of flux vortices in a superconductor taken with a transmission electron microscope can be used to measure the penetration depth and coherence length in all directions at the same temperature and magnetic field. This is particularly useful for MgB2, where these quantities...... vary with the applied magnetic field and values are difficult to obtain at low field or in the c direction. We obtained images of flux vortices from a MgB2 single crystal cut in the ac plane by focused ion beam milling and tilted to 45 degrees. with respect to the electron beam about...... the crystallographic a axis. A new method was developed to simulate these images that accounted for vortices with a nonzero core in a thin, anisotropic superconductor and a simplex algorithm was used to make a quantitative comparison between the images and simulations to measure the penetration depths and coherence...

Measurement and modeling of the low-temperature penetration-depth anomaly in high-quality MgB{sub 2} thin films

Energy Technology Data Exchange (ETDEWEB)

Agassi, Y.D. [Naval Surface Warfare Center, Carderock Division, Bethesda, MD 20817 (United States); Oates, D.E., E-mail: OATES@LL.MIT.EDU [MIT-Lincoln Laboratory, Lexington, MA 02420 (United States); Moeckly, B.H. [STI, Inc. Santa Barbara, CA 93111 (United States)

2012-10-15

Based on our measurements of intermodulation distortion in MgB{sub 2}, we have previously proposed that the {pi} energy-gap in MgB{sub 2} entails six nodal lines [Y.D. Agassi, D.E. Oates, and B.H. Moeckly, Phys. Rev. B 80 (2009) 174522]. Here we report high-precision measurements in MgB{sub 2} stripline resonators that show an increase of the penetration depth as the temperature is decreased below 5 K. This increase is consistent with the Script-Small-L = 6 symmetry of the {pi} energy gap that we have proposed. We interpret the increase as a manifestation of Andreev surface-attached states that are associated with the nodal lines of the {pi} energy gap. Penetration-depth calculations are in good agreement with our data. To reconcile the present interpretation with existing literature, we review other penetration-depth data, magnetic-impurity and tunneling experiments, and data on the paramagnetic Meissner effect. We conclude that these data do not rule out the interpretation of our experimental data based on a nodal {pi} energy gap.

Evidence of weak pair coupling in the penetration depth of bi-based high-Tc superconductors

International Nuclear Information System (INIS)

Thompson, J.R.; Sun, Yang Ren; Ossandon, J.G.; Christen, D.K.; Chakoumakos, B.C.; Sales, B.C.; Kerchner, H.R.; Sonder, E.

1990-01-01

The magnetic penetration depth λ(T) has been investigated in Bi(Pb)SrCaCuO high-T c compounds having 2- and 3-layers of copper-oxygen per unit cell. Studies of the magnetization in the vortex state were employed and the results were compared with weak and strong coupling calculations. The temperature dependence of λ is described well by BCS theory in the clean limit, giving evidence for weak pair coupling in this family of materials. For the short component of the λ tensor, we obtain values of 292 and 220 nm (T = 0) for Bi-2212 and (BiPb)-2223, respectively

Spherical and cylindrical cavity expansion models based prediction of penetration depths of concrete targets.

Directory of Open Access Journals (Sweden)

Xiaochao Jin

Full Text Available The cavity expansion theory is most widely used to predict the depth of penetration of concrete targets. The main purpose of this work is to clarify the differences between the spherical and cylindrical cavity expansion models and their scope of application in predicting the penetration depths of concrete targets. The factors that influence the dynamic cavity expansion process of concrete materials were first examined. Based on numerical results, the relationship between expansion pressure and velocity was established. Then the parameters in the Forrestal's formula were fitted to have a convenient and effective prediction of the penetration depth. Results showed that both the spherical and cylindrical cavity expansion models can accurately predict the depth of penetration when the initial velocity is lower than 800 m/s. However, the prediction accuracy decreases with the increasing of the initial velocity and diameters of the projectiles. Based on our results, it can be concluded that when the initial velocity is higher than the critical velocity, the cylindrical cavity expansion model performs better than the spherical cavity expansion model in predicting the penetration depth, while when the initial velocity is lower than the critical velocity the conclusion is quite the contrary. This work provides a basic principle for selecting the spherical or cylindrical cavity expansion model to predict the penetration depth of concrete targets.

Closed Loop Control of Penetration Depth during CO₂ Laser Lap Welding Processes

Directory of Open Access Journals (Sweden)

Antonio Ancona

2012-08-01

Full Text Available In this paper we describe a novel spectroscopic closed loop control system capable of stabilizing the penetration depth during laser welding processes by controlling the laser power. Our novel approach is to analyze the optical emission from the laser generated plasma plume above the keyhole, to calculate its electron temperature as a process-monitoring signal. Laser power has been controlled by using a quantitative relationship between the penetration depth and the plasma electron temperature. The sensor is able to correlate in real time the difference between the measured electron temperature and its reference value for the requested penetration depth. Accordingly the closed loop system adjusts the power, thus maintaining the penetration depth.

Convenient measurement of the residual stress using X-ray penetration depth

International Nuclear Information System (INIS)

Ukai, Takayoshi; Shibano, Junichi

1994-01-01

The residual stress measured with a characteristic X-ray is usually evaluated as a surface stress. However, it is a weighted mean value over all penetration depth of X-ray. Thus, the classical sin 2 Ψ method with the characteristic X-ray is difficult to use for measuring the steep gradient of residual stress that occurs along the depth direction in a subsurface layer of the material after cold rolling and grinding. This paper presents a convenient method of the residual stress measurement along the depth direction in a subsurface layer using the penetration depth depending on a characteristic X-ray. The residual stress distribution of JIS SKS51 steel plate was measured as an example of applying this method. As a result, it could be confirmed that a residual stress distribution along the depth direction in a subsurface layer could be evaluated nondestructively by this convenient method. (author)

Magnetic field penetration into superconductors with sharp edges

International Nuclear Information System (INIS)

Zhilichev, Yuriy N.

2003-01-01

The magnetic field and surface currents induced within a superconductor are calculated assuming the field penetrates in it near sharp corners. Rounding the corners is used to keep the field less than a critical value. Analytical formulas for a corner radius are given for a wire of the rectangular cross-section and a cylinder in the external magnetic field. A boundary integral method is used to calculate the boundary of the Meissner domain when the external field penetrates deep into the superconductor. The effect of degree of penetration on the magnetic moment of superconducting cylinders and wires is discussed

Conditions for plasmoid penetration across abrupt magnetic barriers

International Nuclear Information System (INIS)

Brenning, Nils; Hurtig, Tomas; Raadu, Michael A.

2005-01-01

The penetration of plasma clouds, or plasmoids, across abrupt magnetic barriers (of the scale less than a few ion gyro radii, using the plasmoid directed velocity) is studied. The insight gained earlier, from detailed experimental and computer simulation investigations of a case study, is generalized into other parameter regimes. It is concluded for what parameters a plasmoid should be expected to penetrate the magnetic barrier through self-polarization, penetrate through magnetic expulsion, or be rejected from the barrier. The scaling parameters are n e , v 0 , B perpendicular , m i , T i , and the width w of the plasmoid. The scaling is based on a model for strongly driven, nonlinear magnetic field diffusion into a plasma which is a generalization of the earlier laboratory findings. The results are applied to experiments earlier reported in the literature, and also to the proposed application of impulsive penetration of plasmoids from the solar wind into the Earth's magnetosphere

Multiaxial stress analysis taking account of penetration depth of x-rays, 3

International Nuclear Information System (INIS)

Yoshioka, Yasuo; Sasaki, Toshihiko; Kuramoto, Makoto.

1985-01-01

In the past X-ray stress analysis in which the effect of stress gradients was taken into account within the penetration depth of X-rays, three assumptions have been made; 1) the stress gradient is linear in respect to the depth from the specimen surface, 2) the penetration depth of X-ray is a function of Sin 2 PSI and 3) the strain measured by X-rays corresponds to the weighted average strain on the intensity of the diffracted X-rays. A problem, however, still remains on the assumption of the X-ray penetration depth. We sometimes observed noticiable errors in the stage of the numerical simulation and these errors depend on the combination of stress components in a stress tensor. In the present paper, we proposed a new X-ray multiaxial stress analysis without using the assumption of the X-ray penetration depth. This analysis is also applicable to both the iso-inclination method ( OHM -goniometer) and the side inclination method (PSI-goniometer). The weighted average strain by X-rays, 1 >(phi), is expressed as a 4th degree function of cosPSI for iso-inclination method and 3rd degree for side inclination method. By rearranging this function as a sum of average strain, ( 1 >(0 0 )+ 1 >(90 0 )), and difference of average strain, ( 1 >(0 0 )- 1 >(90 0 )), we can solve the stress components with sufficient accuracy by a least squares method. The validity of this method was proved through numerical simulations and experiments. (author)

Spatial sensitivity and penetration depth of three cerebral oxygenation monitors

Science.gov (United States)

Gunadi, Sonny; Leung, Terence S.; Elwell, Clare E.; Tachtsidis, Ilias

2014-01-01

The spatial sensitivities of NIRO-100, ISS Oximeter and TRS-20 cerebral oxygenation monitors are mapped using the local perturbation method to inform on their penetration depths and susceptibilities to superficial contaminations. The results show that TRS-20 has the deepest mean penetration depth and is less sensitive than the other monitors to a localized absorption change in the superficial layer. However, an integration time of more than five seconds is required by the TRS-20 to achieve an acceptable level of signal-to-noise ratio, which is the poorest amongst the monitors. With the exception of NIRO-100 continuous wave method, the monitors are not significantly responsive to layer-wide absorption change that occurs in the superficial layer. PMID:25401006

Numerical analysis on effective electric field penetration depth for interdigital impedance sensor

International Nuclear Information System (INIS)

Kim, Chon-ung; Jong, Hakchol; Ro, Cholwu; Pak, Gilhung; Im, Songil; Li, Guofeng; Li, Jie; Song, Yunho

2013-01-01

Interdigital (finger-like) electrodes are widely used for electrical impedance and capacitance tomography of composite dielectric materials and complex insulating structures. Because of their advantages, they are now effectively introduced as capacitance sensors into a variety of industrial branches, agriculture, medical science, biological engineering, military branches, etc. In order to effectively apply the so-called interdigital impedance sensors in practice, of great importance is to optimize the sensor design parameters such as the electric field penetration depth, signal strength and so on. The general design principles of the interdigital capacitance sensor have been discussed for a long time by many researchers. However, there is no consensus on the definition of the effective electric field penetration depth of interdigital electrode. This paper discusses how to determine the effective electric field penetration depth of interdigital sensor on the basis of the refractive principle of electric field intensity and the FEM analyses of electric field distribution and capacitance for the sensor model.

Theory of the c-axis penetration depth in the cuprates

International Nuclear Information System (INIS)

Radtke, R.J.; Kostur, V.N.; Levin, K.

1996-01-01

Recent measurements of the London penetration-depth tensor in the cuprates find a weak temperature dependence along the c direction that is seemingly inconsistent with evidence for d-wave pairing deduced from in-plane measurements. We demonstrate in this paper that these disparate results are not in contradiction, but can be explained within a theory based on incoherent quasiparticle hopping between the CuO 2 layers. By relating the calculated temperature dependence of the penetration depth λ c (T) to the c-axis resistivity, we show how the measured ratio λ 2 c (0)/λ 2 c (T) can provide insight into the behavior of c-axis transport below T c and the related issue of open-quote open-quote confinement.close-quote close-quote copyright 1996 The American Physical Society

The penetration depth and lateral distribution of pigment related to the pigment grain size and the calendering of paper

International Nuclear Information System (INIS)

Buelow, K.; Kristiansson, P.; Schueler, B.; Tullander, E.; Oestling, S.; Elfman, M.; Malmqvist, K.; Pallon, J.; Shariff, A.

2002-01-01

The interaction of ink and newspaper has been investigated and the specific question of penetration of ink into the paper has been addressed with a nuclear microprobe using particle induced X-ray emission. The penetration depth of the newsprint is a critical factor in terms of increasing the quality of newsprint and minimising the amount of ink used. The objective of the experiment was to relate the penetration depth of pigment with the calendering of the paper. The dependence of the penetration depth on the pigment grain size was also studied. To study the penetration depth of pigment in paper, cyan ink with Cu as a tracer of the coloured pigment was used. For the study of the penetration depth dependence of pigment size, specially grounded Japanese ink with well-defined pigment grain size was used. This was compared to Swedish ink with pigment grains with normal size-distribution. The results show that the calendering of the paper considerably affects the penetration depth of ink

Radio frequency absorption and penetration depth limits in whole body MR imaging

International Nuclear Information System (INIS)

Roschmann, P.

1986-01-01

There is a continual debate over the ultimate limits to MR imaging at higher field strengths owing to the problems of increasing radio frequency (RF) power deposition and decreasing depth of B/sub 1/ field penetration in the patient. The authors present experimental results of RF absorption and penetration studies in humans for frequencies (f) of 30 to 220 MHz. Results were mostly derived from RF measurements of the effects of loading different types of head, body, and surface coils during imaging of volunteers and metal phantoms. Imaging at 2 T (85 MHz) does not exhibit significant RF problems; the local SAR amounts to 0.06 W/kg for a π-pulse of 1 msec and a TR of 1 sec. RF measurements of coil loading yield SAR -- f/sup 2.2/. The derived effective penetration depth drops from 17 cm at 85 MHz to 7 cm at 220 MHz. Head imaging appears possible up to 220 MHz (5 T). Body and surface coil imaging is subjected to increasing limitations in size or depth above 100 MHz

Penetration-depth calculations in the ab and c directions in a layered S/N superconductor

International Nuclear Information System (INIS)

Atkinson, W.A.; Carbotte, J.P.

1995-01-01

We present the results of calculations of the penetration depths λ ab and λ c (the subscripts refer to the direction of the screening currents). Our model is a layered superconducting/normal metal (S/N) model, in which the two types of layers are stacked in alternating fashion. The S and N layers are coupled in a coherent fashion and the N layer is driven superconducting by a proximity effect. We calculate the penetration depths for both d-wave and s-wave order parameters for a range of interlayer coupling strengths, and we discuss the effect that the interlayer coupling has on the temperature dependence of the penetration depths. We finish by comparing our results with experimental observations of YBa 2 Cu 3 O 7

Singularity of the London penetration depth at quantum critical points in superconductors.

Science.gov (United States)

Chowdhury, Debanjan; Swingle, Brian; Berg, Erez; Sachdev, Subir

2013-10-11

We present a general theory of the singularity in the London penetration depth at symmetry-breaking and topological quantum critical points within a superconducting phase. While the critical exponents and ratios of amplitudes on the two sides of the transition are universal, an overall sign depends upon the interplay between the critical theory and the underlying Fermi surface. We determine these features for critical points to spin density wave and nematic ordering, and for a topological transition between a superconductor with Z2 fractionalization and a conventional superconductor. We note implications for recent measurements of the London penetration depth in BaFe2(As(1-x)P(x))2 [K. Hashimoto et al., Science 336, 1554 (2012)].

Geometry of X-ray based measurement of residual strain at desired penetration depth

Energy Technology Data Exchange (ETDEWEB)

Morawiec, A. [Polish Academy of Sciences, Institute of Metallurgy and Materials Science, Krakow (Poland)

2017-10-15

X-ray based measurement of residual lattice strains at chosen penetration depth is one of the methods for investigating strain inhomogeneities in near-surface layers of polycrystalline materials. The measurement relies on determining shifts of Bragg peaks for various directions of the scattering vector with respect to the specimen. At each of these directions, to reach a given the penetration depth, a proper specimen orientation is required. The task of determining such orientations, albeit elementary, is quite intricate. The existing literature describes only partial solutions with unspecified domains of application, which fail if applied to beyond the domains. Therefore, geometric aspects of the measurement are analyzed in details. Explicit bounds on measurement parameters are given. The equation fundamental for the procedure is solved with respect to specimen orientations. For a given direction of the scattering vector, there are generally four different specimen orientations leading to the same penetration depth. This simple fact (overlooked in previous analyses) can be used for improving reliability of measurement results. Analytical formulas for goniometer angles representing these orientations are provided. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Penetration depth λ(T) of YBa2Cu3O7-δ films determined from the kinetic inductance

International Nuclear Information System (INIS)

Lee, J.; Lemberger, T.R.

1993-01-01

We examine the temperature dependence of the magnetic penetration depth λ(T) of YBa 2 Cu 3 O 7-δ , determined from the kinetic inductance of a film patterned into a long meander line. This technique has sufficient sensitivity to study λ(T) to lower temperatures than have been examined previously. A numerical model which includes both the magnetic and kinetic inductances of the samples extracts λ(T) from the measured voltage. In reasonable agreement with other measurements, λ(0)∼2100 A is deduced from fitting λ(0) 2 /λ(T) 2 to the function 1-(T/T c ) 2 for T/T c ≥0.4. We find λ(T)/λ(0)-1 is proportional to (T/T c ) 2 for 0.06 ≤T/T c ≤0.4

Evaluation of the penetration depth of the shell welds by electrical methods

International Nuclear Information System (INIS)

Laille, Alain.

1979-07-01

The aim of the present work is the development of two electrical non-destructive methods (eddy currents and potentiometry) to estimate the penetration depth of electron bombardment welds. To illustrate the study and show its potential applications these methods are used on various materials (1 to 3 mm thick) and the results compared with the real welded depth evaluated after sectioning. Finally the potentiometric set-up is coupled to a data acquisition and processing system [fr

Temperature dependence of the optical conductivity and penetration depth in superconductor MgB2 film

International Nuclear Information System (INIS)

Moarrefi, M.; Yavari, H.; Elahi, M.

2010-01-01

By using Green's function method the temperature dependence of the optical conductivity and penetration depth of high-quality MgB 2 film are calculated in the framework of the two-band model. We compare our results with experimental data and we argue that the single gap model is insufficient to describe the optical and penetration depth behavior, but the two-band model with different symmetries describes the data rather well. In the two gap model we consider that the both components of optical conductivity are a weighted sum of the contribution from σ and π bonds and hybridization between them is negligible.

Experimental determination of the temperature-dependent penetration depth in V3Si

International Nuclear Information System (INIS)

Christen, D.K.; Kerchner, H.R.; Sekula, S.T.; Chang, Y.K.

1984-03-01

Small angle neutron diffraction from the flux-line lattice (FLL) in a high quality, single crystal of superconducting V 3 Si has been used to deduce the low-field penetration depth lambda (T). An absolute determination is possible because the FLL form factor F/sub hk/ is essentially single-valued in the scattering vector magnitude absolute value of K/sub hk/, as well as nearly London-like at low field. We obtain lambda (0) = 102 +- 1 nm, 20% to 30% larger than previous determinations of the London penetration depth lambda/sub L/ (0). The temperature dependence of lambda (T) is found to deviate from that of the BCS theory. An assessment of the data indicates the most prominent source of the discrepancy is due to strong electron-phonon coupling, and we find 2Δ(0)/k/sub B/T/sub c/ = 3.88 +- 0.07, in reasonable agreement with values found in the literature

Penetration of magnetic fields into plasmas

International Nuclear Information System (INIS)

Bengtson, R.D.

1976-01-01

A pulsed plasma experiment was constructed to study the penetration of a fast-rising magnetic pulse into an initially unmagnetized, weakly ionized plasma of density 10 11 to 10 13 cm -3 . Magnetic probe data was analyzed using a magnetohydrodynamic approach to obtain detailed information about the dynamics of the penetration mechanism. In particular it is possible to obtain the local resistivity and thus the collision frequency from this data. These collision frequencies compare favorably with theoretical estimates of turbulent collision frequencies. The data indicates that sufficient energy is absorbed to heat the bulk of the plasma to temeratures in excess of 1 keV. A differential rotation of a collisionless theta-pinch column during implosion has been observed and explained by a model in which the driving mechanism is the off-diagonal element p/sub r theta/ of the pressure tensor. Rotational motion was detected by directional probes and spectroscopic techniques. Experimental data were modeled by a one-dimensional hybrid code which included ionization and charge exchange of protons with neutral H atoms

Instability in the magnetic field penetration in type II superconductors

International Nuclear Information System (INIS)

Oliveira, Isaías G. de

2015-01-01

Under the view of the time-dependent Ginzburg–Landau theory we have investigated the penetration of the magnetic field in the type II superconductors. We show that the single vortices, situated along the borderline, between the normal region channel and the superconducting region, can escape to regions still empty of vortices. We show that the origin of this process is the repulsive nature of vortex–vortex interaction, in addition to the non-homogeneous distribution of the vortices along the normal region channel. Using London theory we explain the extra gain of kinetic energy by the vortices situated along this borderline. - Highlights: • TDGL is used to study the magnetic field penetration in type II superconductors. • Instability process is found during the magnetic field penetration. • Vortices along the front of the normal region escape to superconducting region. • We explain the extra-gain of kinetic energy by vortices along the borderline

Effects of magnetic shear on current penetration in a tokamak

International Nuclear Information System (INIS)

Zhang Pengyun; Wang Long

2001-01-01

The penetrations of the parallel and perpendicular components of plasma currents are interrelated to each other due to the existence of magnetic shear in a tokamak configuration. Effects of the shear on the penetration of Fourier components of toroidal plasma current are analysed in a cylindrical column model. The current penetration is obviously strengthened by the shear for a bell-bike conductivity profile and low safety factor and low aspect ratio

Ballistic Phonon Penetration Depth in Amorphous Silicon Dioxide.

Science.gov (United States)

Yang, Lin; Zhang, Qian; Cui, Zhiguang; Gerboth, Matthew; Zhao, Yang; Xu, Terry T; Walker, D Greg; Li, Deyu

2017-12-13

Thermal transport in amorphous silicon dioxide (a-SiO 2 ) is traditionally treated as random walks of vibrations owing to its greatly disordered structure, which results in a mean free path (MFP) approximately the same as the interatomic distance. However, this picture has been debated constantly and in view of the ubiquitous existence of thin a-SiO 2 layers in nanoelectronic devices, it is imperative to better understand this issue for precise thermal management of electronic devices. Different from the commonly used cross-plane measurement approaches, here we report on a study that explores the in-plane thermal conductivity of double silicon nanoribbons with a layer of a-SiO 2 sandwiched in-between. Through comparing the thermal conductivity of the double ribbon samples with that of corresponding single ribbons, we show that thermal phonons can ballistically penetrate through a-SiO 2 of up to 5 nm thick even at room temperature. Comprehensive examination of double ribbon samples with various oxide layer thicknesses and van der Waals bonding strengths allows for extraction of the average ballistic phonon penetration depth in a-SiO 2 . With solid experimental data demonstrating ballistic phonon transport through a-SiO 2 , this work should provide important insight into thermal management of electronic devices.

Estimation of Magnetic Basement Depth of Oyo Area from ...

African Journals Online (AJOL)

Locations and depths to magnetic contacts were estimated from the total intensity magnetic field using Horizontal gradient magnitude (HGM), Analytic signal amplitude (ASA) and Local wavenumber (LWN). The digitized magnetic intensity data of Oyo area, south western Nigeria was analyzed to estimate depths to magnetic ...

The oxygen isotope effect on the in-plane penetration depth in cuprate superconductors

International Nuclear Information System (INIS)

Khasanov, R; Shengelaya, A; Morenzoni, E; Conder, K; Savic, I M; Keller, H

2004-01-01

Muon spin rotation (μSR) studies of the oxygen isotope ( 16 O/ 18 O) effect (OIE) on the in-plane magnetic field penetration depth λ ab in cuprate high-temperature superconductors (HTS) are presented. First, the doping dependence of the OIE on the transition temperature T c in various HTS is briefly discussed. It is observed that different cuprate families show similar doping dependences of the OIE on T c . Then, bulk μSR, low-energy μSR, and magnetization studies of the total and site-selective OIE on λ ab are described in some detail. A substantial OIE on λ ab was observed in various cuprate families at all doping levels, suggesting that cuprate HTS are non-adiabatic superconductors. The experiments clearly demonstrate that the total OIE on T c and λ ab arise from the oxygen sites within the superconducting CuO 2 planes, demonstrating that the phonon modes involving the movement of planar oxygen are dominantly coupled to the supercarriers. Finally, it is shown that the OIE on T c and λ ab exhibit a relation that appears to be generic for different families of cuprate HTS. The observation of these unusual isotope effects implies that lattice effects play an essential role in cuprate HTS and have to be considered in any realistic model of high-temperature superconductivity

Penetration of magnetic field in ferromagnetic transformer sheet

Energy Technology Data Exchange (ETDEWEB)

Sikora, R; Ziolkowski, M

1981-01-12

The paper deals with the penetration of magnetic field in a ferromagnetic transformer sheet. The flux-density distribution is computed using Galerkin's procedure. The different boundary conditions and the nonlinear B/H characteristic is taken into account.

Electric field depth-focality tradeoff in transcranial magnetic stimulation: simulation comparison of 50 coil designs.

Science.gov (United States)

Deng, Zhi-De; Lisanby, Sarah H; Peterchev, Angel V

2013-01-01

Various transcranial magnetic stimulation (TMS) coil designs are available or have been proposed. However, key coil characteristics such as electric field focality and attenuation in depth have not been adequately compared. Knowledge of the coil focality and depth characteristics can help TMS researchers and clinicians with coil selection and interpretation of TMS studies. To quantify the electric field focality and depth of penetration of various TMS coils. The electric field distributions induced by 50 TMS coils were simulated in a spherical human head model using the finite element method. For each coil design, we quantified the electric field penetration by the half-value depth, d(1/2), and focality by the tangential spread, S(1/2), defined as the half-value volume (V(1/2)) divided by the half-value depth, S(1/2) = V(1/2)/d(1/2). The 50 TMS coils exhibit a wide range of electric field focality and depth, but all followed a depth-focality tradeoff: coils with larger half-value depth cannot be as focal as more superficial coils. The ranges of achievable d(1/2) are similar between coils producing circular and figure-8 electric field patterns, ranging 1.0-3.5 cm and 0.9-3.4 cm, respectively. However, figure-8 field coils are more focal, having S(1/2) as low as 5 cm(2) compared to 34 cm(2) for circular field coils. For any coil design, the ability to directly stimulate deeper brain structures is obtained at the expense of inducing wider electrical field spread. Novel coil designs should be benchmarked against comparison coils with consistent metrics such as d(1/2) and S(1/2). Copyright © 2013 Elsevier Inc. All rights reserved.

Magnetic penetration depth and flux dynamics in single-crystal Bi2Sr2CaCu2O8+δ

International Nuclear Information System (INIS)

Harshman, D.R.; Kleiman, R.N.; Inui, M.; Espinosa, G.P.; Mitzi, D.B.; Kapitulnik, A.; Pfiz, T.; Williams, D.L.

1991-01-01

The muon-spin-relaxation technique has been used to study vortex dynamics in single-phase superconducting single crystals of Bi 2 Sr 2 CaCu 2 O 8+δ (T c ∼90 K). The data indicate motional narrowing of the internal field distribution due to vortex motion (on a time scale comparable to the muon lifetime). A field-dependent lattice transition is also observed at T x ∼30 K, as evidenced by the onset of an asymmetric line shape below T x . Narrowing arising from disordering of the vortices along [001] is also discussed with reference to its effect on the measured penetration depth

Multiaxial stress analysis taking account of the penetration depth of x-rays, (1)

International Nuclear Information System (INIS)

Sasaki, Toshihiko; Yoshioka, Yasuo; Kuramoto, Makoto.

1983-01-01

The new theory of X-ray multiaxial stress measurement is proposed. This method takes accounts of the influence concerning to the stress gradient and to the dependence of the penetration depth of X-rays upon the incidence angle. As a basic assumption, it's assumed that (1) stress gradient is linear in respect to the depth from the specimen surface, (2) the penetration depth of X-rays shows linear dependence upon sin 2 PSI, and (3) the lattice strain determined by X-rays corresponds to the weighted averaging strain on the intensity of the diffracted X-rays. Consequently, the stress state within the thin layer near to the surface is expressed by making use of three surface stresses and six stress gradients in this theory. It was proved that these nine stress elements were able to be solved through X-ray method by applying ''the integral method'' proposed by Lode and Peiter in 1976. The verification of the validity on this method was carried out through the numerical simulation and residual stress measurement of a ground S55C. As a result, it was found that this method could get a satisfactory accuracy. This method can estimate the multiaxial stress distribution within the surface layer nondestructively. (author)

Particle-in-cell simulations of fast magnetic field penetration into plasmas due to the Hall electric field

International Nuclear Information System (INIS)

Swanekamp, S.B.; Grossmann, J.M.; Fruchtman, A.; Oliver, B.V.; Ottinger, P.F.

1996-01-01

Particle-in-cell (PIC) simulations are used to study the penetration of magnetic field into plasmas in the electron-magnetohydrodynamic (EMHD) regime. These simulations represent the first definitive verification of EMHD with a PIC code. When ions are immobile, the PIC results reproduce many aspects of fluid treatments of the problem. However, the PIC results show a speed of penetration that is between 10% and 50% slower than predicted by one-dimensional fluid treatments. In addition, the PIC simulations show the formation of vortices in the electron flow behind the EMHD shock front. The size of these vortices is on the order of the collisionless electron skin depth and is closely coupled to the effects of electron inertia. An energy analysis shows that one-half the energy entering the plasma is stored as magnetic field energy while the other half is shared between internal plasma energy (thermal motion and electron vortices) and electron kinetic energy loss from the volume to the boundaries. The amount of internal plasma energy saturates after an initial transient phase so that late in time the rate that magnetic energy increases in the plasma is the same as the rate at which kinetic energy flows out through the boundaries. When ions are mobile it is observed that axial magnetic field penetration is followed by localized thinning in the ion density. The density thinning is produced by the large electrostatic fields that exist inside the electron vortices which act to reduce the space-charge imbalance necessary to support the vortices. This mechanism may play a role during the opening process of a plasma opening switch. copyright 1996 American Institute of Physics

The Tubular Penetration Depth and Adaption of Four Sealers: A Scanning Electron Microscopic Study

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Huan Chen

2017-01-01

Full Text Available Background. The tubular penetration and adaptation of the sealer are important factors for successful root canal filling. The aim of this study was to evaluate the tubular penetration depth of four different sealers in the coronal, middle, and apical third of root canals as well as the adaptation of these sealers to root canal walls. Materials and Methods. 50 single-rooted teeth were prepared in this study. Forty-eight of them were filled with different sealers (Cortisomol, iRoot SP, AH-Plus, and RealSeal SE and respective core filling materials. Then the specimens were sectioned and scanning electron microscopy was employed to assess the tubular penetration and adaptation of the sealers. Results. Our results demonstrated that the maximum penetration was exhibited by RealSeal SE, followed by AH-Plus, iRoot SP, and Cortisomol. As regards the adaptation property to root canal walls, AH-Plus has best adaptation capacity followed by iRoot SP, RealSeal SE, and Cortisomol. Conclusion. The tubular penetration and adaptation vary with the different sealers investigated. RealSeal SE showed the most optimal tubular penetration, whereas AH-Plus presented the best adaptation to the root canal walls.

The oxygen isotope effect on the in-plane penetration depth in cuprate superconductors

Energy Technology Data Exchange (ETDEWEB)

Khasanov, R [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland); Shengelaya, A [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland); Morenzoni, E [Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland); Conder, K [Laboratory for Neutron Scattering, ETH Zuerich and PSI Villigen, CH-5232 Villigen PSI (Switzerland); Savic, I M [Faculty of Physics, University of Belgrade, 11001 Belgrade (Serbia and Montenegro); Keller, H [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland)

2004-10-13

Muon spin rotation ({mu}SR) studies of the oxygen isotope ({sup 16}O/{sup 18}O) effect (OIE) on the in-plane magnetic field penetration depth {lambda}{sub ab} in cuprate high-temperature superconductors (HTS) are presented. First, the doping dependence of the OIE on the transition temperature T{sub c} in various HTS is briefly discussed. It is observed that different cuprate families show similar doping dependences of the OIE on T{sub c}. Then, bulk {mu}SR, low-energy {mu}SR, and magnetization studies of the total and site-selective OIE on {lambda}{sub ab} are described in some detail. A substantial OIE on {lambda}{sub ab} was observed in various cuprate families at all doping levels, suggesting that cuprate HTS are non-adiabatic superconductors. The experiments clearly demonstrate that the total OIE on T{sub c} and {lambda}{sub ab} arise from the oxygen sites within the superconducting CuO{sub 2} planes, demonstrating that the phonon modes involving the movement of planar oxygen are dominantly coupled to the supercarriers. Finally, it is shown that the OIE on T{sub c} and {lambda}{sub ab} exhibit a relation that appears to be generic for different families of cuprate HTS. The observation of these unusual isotope effects implies that lattice effects play an essential role in cuprate HTS and have to be considered in any realistic model of high-temperature superconductivity.

Investigating skin penetration depth and shape following needle-free injection at different pressures: A cadaveric study.

Science.gov (United States)

Seok, Joon; Oh, Chang Taek; Kwon, Hyun Jung; Kwon, Tae Rin; Choi, Eun Ja; Choi, Sun Young; Mun, Seog Kyun; Han, Seung-Ho; Kim, Beom Joon; Kim, Myeung Nam

2016-08-01

The effectiveness of needle-free injection devices in neocollagenesis for treating extended skin planes is an area of active research. It is anticipated that needle-free injection systems will not only be used to inject vaccines or insulin, but will also greatly aid skin rejuvenation when used to inject aesthetic materials such as hyaluronic acid, botulinum toxin, and placental extracts. There has not been any specific research to date examining how materials penetrate the skin when a needle-free injection device is used. In this study, we investigated how material infiltrates the skin when it is injected into a cadaver using a needle-free device. Using a needle-free injector (INNOJECTOR™; Amore Pacific, Seoul, Korea), 0.2 ml of 5% methylene blue (MB) or latex was injected into cheeks of human cadavers. The device has a nozzle diameter of 100 µm and produces a jet with velocity of 180 m/s. This jet penetrates the skin and delivers medicine intradermally via liquid propelled by compressed gasses. Materials were injected at pressures of 6 or 8.5 bars, and the injection areas were excised after the procedure. The excised areas were observed visually and with a phototrichogram to investigate the size, infiltration depth, and shape of the hole created on the skin. A small part of the area that was excised was magnified and stained with H&E (×40) for histological examination. We characterized the shape, size, and depth of skin infiltration following injection of 5% MB or latex into cadaver cheeks using a needle-free injection device at various pressure settings. Under visual inspection, the injection at 6 bars created semi-circle-shaped hole that penetrated half the depth of the excised tissue, while injection at 8.5 bars created a cylinder-shaped hole that spanned the entire depth of the excised tissue. More specific measurements were collected using phototrichogram imaging. The shape of the injection entry point was consistently spherical regardless of the

A new polarized neutrons method for studying depth-inhomogeneously magnetized magnetic films

International Nuclear Information System (INIS)

Korneev, D.A.

1990-01-01

The main specific features of the process of polarized thermal neutrons specular reflection from the surface of depth-inhomogeneously magnetic films are considered theoretically. It is shown how using the method of specular reflection of polarized thermal neutrons from such a films surface, one may restore the depth distribution of the local magnetization vector M-vector(z). 9 refs

Comprehensive Survey on Improved Focality and Penetration Depth of Transcranial Magnetic Stimulation Employing Multi-Coil Arrays

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Xile Wei

2017-11-01

Full Text Available Multi-coil arrays applied in transcranial magnetic stimulation (TMS are proposed to accurately stimulate brain tissues and modulate neural activities by an induced electric field (EF. Composed of numerous independently driven coils, a multi-coil array has alternative energizing strategies to evoke EFs targeting at different cerebral regions. To improve the locating resolution and the stimulating focality, we need to fully understand the variation properties of induced EFs and the quantitative control method of the spatial arrangement of activating coils, both of which unfortunately are still unclear. In this paper, a comprehensive analysis of EF properties was performed based on multi-coil arrays. Four types of planar multi-coil arrays were used to study the relationship between the spatial distribution of EFs and the structure of stimuli coils. By changing coil-driven strategies in a basic 16-coil array, we find that an EF induced by compactly distributed coils decays faster than that induced by dispersedly distributed coils, but the former has an advantage over the latter in terms of the activated brain volume. Simulation results also indicate that the attenuation rate of an EF induced by the 36-coil dense array is 3 times and 1.5 times greater than those induced by the 9-coil array and the 16-coil array, respectively. The EF evoked by the 36-coil dispense array has the slowest decay rate. This result demonstrates that larger multi-coil arrays, compared to smaller ones, activate deeper brain tissues at the expense of decreased focality. A further study on activating a specific field of a prescribed shape and size was conducted based on EF variation. Accurate target location was achieved with a 64-coil array 18 mm in diameter. A comparison between the figure-8 coil, the planar array, and the cap-formed array was made and demonstrates an improvement of multi-coil configurations in the penetration depth and the focality. These findings suggest

Comprehensive Survey on Improved Focality and Penetration Depth of Transcranial Magnetic Stimulation Employing Multi-Coil Arrays.

Science.gov (United States)

Wei, Xile; Li, Yao; Lu, Meili; Wang, Jiang; Yi, Guosheng

2017-11-14

Multi-coil arrays applied in transcranial magnetic stimulation (TMS) are proposed to accurately stimulate brain tissues and modulate neural activities by an induced electric field (EF). Composed of numerous independently driven coils, a multi-coil array has alternative energizing strategies to evoke EFs targeting at different cerebral regions. To improve the locating resolution and the stimulating focality, we need to fully understand the variation properties of induced EFs and the quantitative control method of the spatial arrangement of activating coils, both of which unfortunately are still unclear. In this paper, a comprehensive analysis of EF properties was performed based on multi-coil arrays. Four types of planar multi-coil arrays were used to study the relationship between the spatial distribution of EFs and the structure of stimuli coils. By changing coil-driven strategies in a basic 16-coil array, we find that an EF induced by compactly distributed coils decays faster than that induced by dispersedly distributed coils, but the former has an advantage over the latter in terms of the activated brain volume. Simulation results also indicate that the attenuation rate of an EF induced by the 36-coil dense array is 3 times and 1.5 times greater than those induced by the 9-coil array and the 16-coil array, respectively. The EF evoked by the 36-coil dispense array has the slowest decay rate. This result demonstrates that larger multi-coil arrays, compared to smaller ones, activate deeper brain tissues at the expense of decreased focality. A further study on activating a specific field of a prescribed shape and size was conducted based on EF variation. Accurate target location was achieved with a 64-coil array 18 mm in diameter. A comparison between the figure-8 coil, the planar array, and the cap-formed array was made and demonstrates an improvement of multi-coil configurations in the penetration depth and the focality. These findings suggest that there is a

Implementation of pencil kernel and depth penetration algorithms for treatment planning of proton beams

International Nuclear Information System (INIS)

Russell, K.R.; Saxner, M.; Ahnesjoe, A.; Montelius, A.; Grusell, E.; Dahlgren, C.V.

2000-01-01

The implementation of two algorithms for calculating dose distributions for radiation therapy treatment planning of intermediate energy proton beams is described. A pencil kernel algorithm and a depth penetration algorithm have been incorporated into a commercial three-dimensional treatment planning system (Helax-TMS, Helax AB, Sweden) to allow conformal planning techniques using irregularly shaped fields, proton range modulation, range modification and dose calculation for non-coplanar beams. The pencil kernel algorithm is developed from the Fermi-Eyges formalism and Moliere multiple-scattering theory with range straggling corrections applied. The depth penetration algorithm is based on the energy loss in the continuous slowing down approximation with simple correction factors applied to the beam penumbra region and has been implemented for fast, interactive treatment planning. Modelling of the effects of air gaps and range modifying device thickness and position are implicit to both algorithms. Measured and calculated dose values are compared for a therapeutic proton beam in both homogeneous and heterogeneous phantoms of varying complexity. Both algorithms model the beam penumbra as a function of depth in a homogeneous phantom with acceptable accuracy. Results show that the pencil kernel algorithm is required for modelling the dose perturbation effects from scattering in heterogeneous media. (author)

Estimation of penetration depth of fission products in cladding Hull

International Nuclear Information System (INIS)

Kim, Hee Moon; Jung, Yang Hong; Yoo, Byong Ok; Choo, Yong Sun; Hong, Kwon Pyo

2005-01-01

A disposal and a reprocessing for spent fuel rod with high burnup need de-cladding procedure. Pellet in this rod has been separated from a cladding hull to reduce a radioactivity of hull by chemical and mechanical methods. But fission products and actinides(U,Pu) still remain inside of cladding hull by chemical bonding and fission spike, which is called as 'contamination'. More specific removal of this contamination would have been considered. In this study, the sorts of fission products and penetration depth in hull were observed by EPMA test. To analyze this behavior, SRIM 2000 code was also used as energies of fission products and an oxide thickness of hull

Sedimentary basins reconnaissance using the magnetic Tilt-Depth method

Science.gov (United States)

Salem, A.; Williams, S.; Samson, E.; Fairhead, D.; Ravat, D.; Blakely, R.J.

2010-01-01

We compute the depth to the top of magnetic basement using the Tilt-Depth method from the best available magnetic anomaly grids covering the continental USA and Australia. For the USA, the Tilt-Depth estimates were compared with sediment thicknesses based on drilling data and show a correlation of 0.86 between the datasets. If random data were used then the correlation value goes to virtually zero. There is little to no lateral offset of the depth of basinal features although there is a tendency for the Tilt-Depth results to be slightly shallower than the drill depths. We also applied the Tilt-Depth method to a local-scale, relatively high-resolution aeromagnetic survey over the Olympic Peninsula of Washington State. The Tilt-Depth method successfully identified a variety of important tectonic elements known from geological mapping. Of particular interest, the Tilt-Depth method illuminated deep (3km) contacts within the non-magnetic sedimentary core of the Olympic Mountains, where magnetic anomalies are subdued and low in amplitude. For Australia, the Tilt-Depth estimates also give a good correlation with known areas of shallow basement and sedimentary basins. Our estimates of basement depth are not restricted to regional analysis but work equally well at the micro scale (basin scale) with depth estimates agreeing well with drill hole and seismic data. We focus on the eastern Officer Basin as an example of basin scale studies and find a good level of agreement between previously-derived basin models. However, our study potentially reveals depocentres not previously mapped due to the sparse distribution of well data. This example thus shows the potential additional advantage of the method in geological interpretation. The success of this study suggests that the Tilt-Depth method is useful in estimating the depth to crystalline basement when appropriate quality aeromagnetic anomaly data are used (i.e. line spacing on the order of or less than the expected depth to

Effective depth-of-penetration range due to hardness variation for different lots of nominally identical target material

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Patrick Frueh

2016-04-01

A linear regression analysis of penetration vs. hardness shows that a target hardness increase within the given range of 280–330 BHN may result in a reduction of penetration depth of about 5.8 mm at constant velocity. This is equal to a change of −12% at an impact velocity of 1250 m/s. A multiple linear regression analysis included also the influence of yaw angle and impact velocity. It shows that small yaw angles and slight variations of impact velocities provide a smaller variation of the semi-infinite penetration depths than a variation of target hardness within a typical specification span of 50 BHN. For such a span a change in penetration of approximately −4.8 mm due to hardness variation is found, whereas 1° of yaw angle or −10 m/s of velocity variation gives a change of about −1.0 mm respectively −0.9 mm. For the given example, the overwhelming part of the variation is to be attributed to hardness effects – 4.8 mm out of 5.8 mm (83%. For nominally identical target material the target hardness thus influences the ballistic test results more severely than the typical scatter in impact conditions.

Transcranial magnetic stimulation: Improved coil design for deep brain investigation

Science.gov (United States)

Crowther, L. J.; Marketos, P.; Williams, P. I.; Melikhov, Y.; Jiles, D. C.; Starzewski, J. H.

2011-04-01

This paper reports on a design for a coil for transcranial magnetic stimulation. The design shows potential for improving the penetration depth of the magnetic field, allowing stimulation of subcortical structures within the brain. The magnetic and induced electric fields in the human head have been calculated with finite element electromagnetic modeling software and compared with empirical measurements. Results show that the coil design used gives improved penetration depth, but also indicates the likelihood of stimulation of additional tissue resulting from the spatial distribution of the magnetic field.

Transverse magnetic field penetration through the JET toroidal coil and support structure

International Nuclear Information System (INIS)

Core, W.G.F.; Noll, P.

1988-01-01

This report contains the results of a study of transverse magnetic field penetration through the JET magnetic field coil systems and supporting structures. The studies were carried out during the initial JET design phase (1973-78) and were part of a major radius compression plasma heating feasibility study. In view of the interest in this problem the authors have decided to re-issue the original work as a JET report. The material basically remains unchanged although better estimates of the penetration times have been obtained and typographical errors which occurred in the original have been corrected. (author)

Measurement of residual stress in a sphere by x-ray under the consideration of its penetration depth

International Nuclear Information System (INIS)

Doi, Osamu; Ukai, Takayoshi

1981-01-01

It was pointed out in the case of a plate that when stress gradient is large, the use of the X-ray with large penetration depth caused large measurement error. In this paper, the theoretical equations for measuring the residual stress in a sphere with X-ray, taking penetration depth into account, are proposed, and the example of application is shown. As the method of measuring the residual stress in a hollow sphere with X-ray, only the method of combining external surface removal and external surface irradiation is practically in use. It was assumed that a sphere is isotropic, and that the residual stress is a function of the radius only. First, the theory of measuring the residual stress in a sphere with X-ray taking penetration depth into account is explained, and the equations for calculating the residual stresses in tangential and radial directions are derived. As the example of applying this theory, the distribution of the residual stress in a steel ball for a ball bearing was measured with Cr characteristic X-ray. The ball of 30 mm diameter was made of high-carbon chromium bearing steel, grade 2, (JIS SUJ2) and quenched and tempered. The removal of the thin layer was made by chemical etching and electrolysis. The measured values and the calculated values are shown. (Kako, I.)

Non-London electrodynamics in a multiband London model: Anisotropy-induced nonlocalities and multiple magnetic field penetration lengths

Science.gov (United States)

Silaev, Mihail; Winyard, Thomas; Babaev, Egor

2018-05-01

The London model describes strongly type-2 superconductors as massive vector field theories, where the magnetic field decays exponentially at the length scale of the London penetration length. This also holds for isotropic multiband extensions, where the presence of multiple bands merely renormalizes the London penetration length. We show that, by contrast, the magnetic properties of anisotropic multiband London models are not this simple, and the anisotropy leads to the interband phase differences becoming coupled to the magnetic field. This results in the magnetic field in such systems having N +1 penetration lengths, where N is the number of field components or bands. That is, in a given direction, the magnetic field decay is described by N +1 modes with different amplitudes and different decay length scales. For certain anisotropies we obtain magnetic modes with complex masses. That means that magnetic field decay is not described by a monotonic exponential increment set by a real penetration length but instead is oscillating. Some of the penetration lengths are shown to diverge away from the superconducting phase transition when the mass of the phase-difference mode vanishes. Finally the anisotropy-driven hybridization of the London mode with the Leggett modes can provide an effectively nonlocal magnetic response in the nominally local London model. Focusing on the two-component model, we discuss the magnetic field inversion that results from the effective nonlocality, both near the surface of the superconductor and around vortices. In the regime where the magnetic field decay becomes nonmonotonic, the multiband London superconductor is shown to form weakly-bound states of vortices.

The Impact of Microwave Penetration Depth on the Process of Heating the Moulding Sand with Sodium Silicate

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Nowak D.

2017-12-01

Full Text Available This paper presents the impact of microwave penetration depth on the process of heating the moulding sand with sodium silicate. For each material it is affected by: the wavelength in vacuum and the real and imaginary components of the relative complex electrical permittivity εr for a selected measurement frequency. Since the components are not constant values and they change depending on the electrical parameters of materials and the frequency of the electromagnetic wave, it is indispensable to carry out laboratory measurements to determine them. Moreover, the electrical parameters of materials are also affected by: temperature, packing degree, humidity and conductivity. The measurements of the dielectric properties of moulding sand with sodium silicate was carried out using the perturbation method on a stand of waveguide resonance cavity. The real and imaginary components of the relative complex electrical permittivity was determined for moulding sand at various contents of sodium silicate and at various packing degrees of the samples. On the basis of the results the microwave penetration depth of moulding sand with sodium silicate was established. Relative literature contains no such data that would be essential to predicting an effective process of microwave heating of moulding sand with sodium silicate. Both the packing degree and the amount of sodium silicate in moulding sand turned out to affect the penetration depth, which directly translates into microwave power density distribution in the process of microwave heating of moulding sand with sodium silicate.

Pressure-driven amplification and penetration of resonant magnetic perturbations

Energy Technology Data Exchange (ETDEWEB)

Loizu, J. [Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald (Germany); Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Hudson, S. R.; Lazerson, S. A.; Bhattacharjee, A. [Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 (United States); Helander, P. [Max-Planck-Institut für Plasmaphysik, D-17491 Greifswald (Germany)

2016-05-15

We show that a resonant magnetic perturbation applied to the boundary of an ideal plasma screw-pinch equilibrium with nested surfaces can penetrate inside the resonant surface and into the core. The response is significantly amplified with increasing plasma pressure. We present a rigorous verification of nonlinear equilibrium codes against linear theory, showing excellent agreement.

Low temperature London penetration depth and superfluid density in Fe-based superconductors

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyunsoo [Iowa State Univ., Ames, IA (United States)

2013-01-01

The superconducting gap symmetry of the Fe-based superconductors was studied by measurements and analysis of London penetration depth and super uid density. Tunnel diode resonator technique for these measurements was implemented in a dilution refrigerator allowing for the temperatures down to 50 mK. For the analysis of the super uid density, we used both experimental studies of Al-coated samples and original thermodynamic approach based on Rutgers relation. In three systems studied, we found that the superconducting gap at the optimal doping is best described in multi-gap full gap scenario. By performing experiments on samples with arti cially introduced disorder with heavy ion irradiation, we show that evolution of the superconducting transition temperature and of the super uid density are consistent with full-gap sign changing s superconducting state. The superconducting gap develops strong modulation both in the under-doped and the over-doped regimes. In the terminal hole-doped KFe{sub 2}As{sub 2}, both temperature dependence of the super uid density and its evolution with increase of the scattering rate are consistent with symmetry imposed vertical line nodes in the superconducting gap. By comparative studies of hole-doped (Ba,K)Fe{sub 2}As{sub 2} and electron-doped Ca10-3-8, we show that the superconducting gap modulation in the under-doped regime is intrinsic and is not induced by the coexisting static magnetic order.

Magnetic Basement Depth Inversion in the Space Domain

Science.gov (United States)

Nunes, Tiago Mane; Barbosa, Valéria Cristina F.; Silva, João Batista C.

2008-10-01

We present a total-field anomaly inversion method to determine both the basement relief and the magnetization direction (inclination and declination) of a 2D sedimentary basin presuming negligible sediment magnetization. Our method assumes that the magnetic intensity contrast is constant and known. We use a nonspectral approach based on approximating the vertical cross section of the sedimentary basin by a polygon, whose uppermost vertices are forced to coincide with the basin outcrop, which are presumably known. For fixed values of the x coordinates our method estimates the z coordinates of the unknown polygon vertices. To obtain the magnetization direction we assume that besides the total-field anomaly, information about the basement’s outcrops at the basin borders and the basement depths at a few points is available. To obtain stable depth-to-basement estimates we impose overall smoothness and positivity constraints on the parameter estimates. Tests on synthetic data showed that the simultaneous estimation of the irregular basement relief and the magnetization direction yields good estimates for the relief despite the mild instability in the magnetization direction. The inversion of aeromagnetic data from the onshore Almada Basin, Brazil, revealed a shallow, eastward-dipping basement basin.

Eddy current testing with high penetration

International Nuclear Information System (INIS)

Becker, R.; Kroening, M.

1999-01-01

The low-frequency eddy current testing method is used when penetration into very deep layers is required. The achievable penetration depth is determined among other parameters by the lowest testing frequency that can be realised together with the eddy current sensor. When using inductive sensors, the measuring effect declines proportional to the lowering frequency (induction effect). Further reduction of testing frequency requires other types of sensors, as e.g. the GMR (Giant Magnetic Resistance), which achieves a constant measuring sensitivity down to the steady field. The multi-frequency eddy current testing method MFEC 3 of IZFP described here can be operated using three different scanning frequencies at a time. Two variants of eddy current probes are used in this case. Both have an inductive winding at their emitters, of the type of a measuring probe. The receiver end is either also an inductive winding, or a magnetic field-responsive resistance (GMR). (orig./CB) [de

Depth of magnetic basement in Iran based on fractal spectral analysis of aeromagnetic data

Science.gov (United States)

Teknik, Vahid; Ghods, Abdolreza

2017-06-01

To estimate the shape of sedimentary basins, a critical parameter in hydrocarbon exploration, we calculated the depth of magnetic basement by applying a fractal spectral method to the aeromagnetic map of Iran. The depth of magnetic basement is a close proxy for the shape of sedimentary basins provided that igneous basement is strongly magnetized relative to the overlying sediments and there is no interbedding magnetic layer in the sediments. The shape of the power spectrum of magnetic anomalies is sensitive to the depth of magnetic basement, the thickness of the magnetic layer, the fractal parameter of magnetization and the size of the window used for the calculation of the power spectrum. Using a suite of synthetic tests, we have shown that the estimation of the depth of magnetic basement of up to 20 km is not very sensitive to the often unknown fractal parameter and thus the spectral method is a reliable tool to calculate the depth of magnetic basement. The depth of magnetic basement is in the range of 7-16 km in the Zagros, east Alborz, Tabas, Jazmurian and Makran regions, showing a close correlation with depths estimated from the maximum thickness of stratigraphic columns. We have also found new sedimentary basins in Bostan Abad, Bijar and south of Orumiyeh Lake. The significant depth of the magnetic basement in the Makran, Jazmurain depression, southeast Caspian Sea, Tabas, Great Kavir, south of Orumiyeh Lake, Bostan Abad and Bijar sedimentary basins makes them future prospects for hydrocarbon explorations. The depth of magnetic basement is strongly reduced over the Neyriz and Kermanshah Ophiolites, but it does not show any meaningful correlation with other outcrops of ophiolitic rocks in Iran.

Monopole conversion hidden by penetration effect in magnetic dipole transitions

International Nuclear Information System (INIS)

Bikit, I.; Anichin, I.; Marinkov, L.

1977-01-01

The 191 keV 197 Au nad 340 keV 233 U transitions are investigated and the effect of penetration into the M1-component is accounted for. Theoretical internal conversion coefficients (ICC) and electron parameters to account for the penetration effect have been obtained by interpolating the data of the Hager and Zeltzer tables. The ICC values and ratios are analyzed under the assumption that the 191 keV 197 Au transition has multipolarities M1 + E2 and E 0 +M1. A common overlapping occurs when the nuclear penetration parameter lambda for magnetic dipole transition is lambda = 34.2+-2.2. For the 340 keV 233 U transition the ICC has been found to equal αk=0.69+-0.07, and the relative conversion-line intensities have been determined. It is concluded that the 191 keV 197 Au nad 340 keV 233 U transitions involve an electric monopole component concealed by the penetration effect in the M1-conversion. The matrix elements of the E0-transition have been evaluated

Influence of jet thrust on penetrator penetration when studying the structure of space object blanket

Directory of Open Access Journals (Sweden)

N. A. Fedorova

2014-01-01

Full Text Available The article presents the calculation-and-theory-based research results to examine the possibility for using the jet thrust impulse to increase a penetration depth of high-velocity penetrator modules. Such devices can be used for studies of Earth surface layer composition, and in the nearest future for other Solar system bodies too. Research equipment (sensors and different instruments is housed inside a metal body of the penetrator with a sharpened nose that decreases drag force in soil. It was assumed, that this penetrator is additionally equipped with the pulse jet engine, which is fired at a certain stage of penetrator motion into target.The penetrator is considered as a rigid body of variable mass, which is subjected to drag force and reactive force applied at the moment the engine fires. A drag force was represented with a binomial empirical law, and penetrator nose part was considered to be conical. The jet thrust force was supposed to be constant during its application time. It was in accordance with assumption that mass flow and flow rate of solid propellant combustion products were constant. The amount of propellant in the penetrator was characterized by Tsiolkovsky number Z, which specifies the ratio between the fuel mass and the penetrator structure mass with no fuel.The system of equations to describe the penetrator dynamics was given in dimensionless form using the values aligned with penetration of an equivalent inert penetrator as the time and penetration depth scales. Penetration dynamics of penetrator represented in this form allowed to eliminate the influence of penetrator initial mass and its cross-section diameter on the solution results. The lack of such dependency is convenient for comparing the calculation results since they hold for penetrators of various initial masses and cross-sections.To calculate the penetration a lunar regolith was taken as a soil material. Calculations were carried out for initial velocities of

Penetration Depth and Defect Image Contrast Formation in Grazing-Incidence X-ray Topography of 4H-SiC Wafers

Science.gov (United States)

Yang, Yu; Guo, Jianqiu; Goue, Ouloide Yannick; Kim, Jun Gyu; Raghothamachar, Balaji; Dudley, Michael; Chung, Gill; Sanchez, Edward; Manning, Ian

2018-02-01

Synchrotron x-ray topography in grazing-incidence geometry is useful for discerning defects at different depths below the crystal surface, particularly for 4H-SiC epitaxial wafers. However, the penetration depths measured from x-ray topographs are much larger than theoretical values. To interpret this discrepancy, we have simulated the topographic contrast of dislocations based on two of the most basic contrast formation mechanisms, viz. orientation and kinematical contrast. Orientation contrast considers merely displacement fields associated with dislocations, while kinematical contrast considers also diffraction volume, defined as the effective misorientation around dislocations and the rocking curve width for given diffraction vector. Ray-tracing simulation was carried out to visualize dislocation contrast for both models, taking into account photoelectric absorption of the x-ray beam inside the crystal. The results show that orientation contrast plays the key role in determining both the contrast and x-ray penetration depth for different types of dislocation.

Crystal growth vs. conventional acid etching: A comparative evaluation of etch patterns, penetration depths, and bond strengths

Directory of Open Access Journals (Sweden)

Devanna Raghu

2008-01-01

Full Text Available The present study was undertaken to investigate the effect on enamel surface, penetration depth, and bond strength produced by 37% phosphoric acid and 20% sulfated polyacrylic acid as etching agents for direct bonding. Eighty teeth were used to study the efficacy of the etching agents on the enamel surface, penetration depth, and tensile bond strength. It was determined from the present study that a 30 sec application of 20% sulfated polyacrylic acid produced comparable etching topography with that of 37% phosphoric acid applied for 30 sec. The 37% phosphoric acid dissolves enamel to a greater extent than does the 20% sulfated polyacrylic acid. Instron Universal testing machine was used to evaluate the bond strengths of the two etching agents. Twenty percent sulfated polyacrylic acid provided adequate tensile bond strength. It was ascertained that crystal growth can be an alternative to conventional phosphoric acid etching as it dissolves lesser enamel and provides adequate tensile bond strength.

There’s plenty of light at the bottom: statistics of photon penetration depth in random media

Science.gov (United States)

Martelli, Fabrizio; Binzoni, Tiziano; Pifferi, Antonio; Spinelli, Lorenzo; Farina, Andrea; Torricelli, Alessandro

2016-01-01

We propose a comprehensive statistical approach describing the penetration depth of light in random media. The presented theory exploits the concept of probability density function f(z|ρ, t) for the maximum depth reached by the photons that are eventually re-emitted from the surface of the medium at distance ρ and time t. Analytical formulas for f, for the mean maximum depth 〈zmax〉 and for the mean average depth reached by the detected photons at the surface of a diffusive slab are derived within the framework of the diffusion approximation to the radiative transfer equation, both in the time domain and the continuous wave domain. Validation of the theory by means of comparisons with Monte Carlo simulations is also presented. The results are of interest for many research fields such as biomedical optics, advanced microscopy and disordered photonics. PMID:27256988

Study of temperature increase and optic depth penetration in photo irradiated human tissues

International Nuclear Information System (INIS)

Stolik, Suren; Delgado, Jose A.; Perez, Arllene M.; Anasagasti, Lorenzo

2009-01-01

Optical radiation is widely applied in the treatment and diagnosis of different pathologies. If the power density of the incident light is sufficiently high to induce a significant temperature rise in the irradiated tissue, then it is also needed the knowledge of the thermal properties of the tissue for a complete understanding of the therapeutic effects. The thermal penetration depth of several human tissues has been measured applying the diffusion approximation of the radiative transfer equation for the distribution of optical radiation. The method, the experimental setup and the results are presented and discussed. (Author)

Depth of origin of ocean-circulation-induced magnetic signals

Science.gov (United States)

Irrgang, Christopher; Saynisch-Wagner, Jan; Thomas, Maik

2018-01-01

As the world ocean moves through the ambient geomagnetic core field, electric currents are generated in the entire ocean basin. These oceanic electric currents induce weak magnetic signals that are principally observable outside of the ocean and allow inferences about large-scale oceanic transports of water, heat, and salinity. The ocean-induced magnetic field is an integral quantity and, to first order, it is proportional to depth-integrated and conductivity-weighted ocean currents. However, the specific contribution of oceanic transports at different depths to the motional induction process remains unclear and is examined in this study. We show that large-scale motional induction due to the general ocean circulation is dominantly generated by ocean currents in the upper 2000 m of the ocean basin. In particular, our findings allow relating regional patterns of the oceanic magnetic field to corresponding oceanic transports at different depths. Ocean currents below 3000 m, in contrast, only contribute a small fraction to the ocean-induced magnetic signal strength with values up to 0.2 nT at sea surface and less than 0.1 nT at the Swarm satellite altitude. Thereby, potential satellite observations of ocean-circulation-induced magnetic signals are found to be likely insensitive to deep ocean currents. Furthermore, it is shown that annual temporal variations of the ocean-induced magnetic field in the region of the Antarctic Circumpolar Current contain information about sub-surface ocean currents below 1000 m with intra-annual periods. Specifically, ocean currents with sub-monthly periods dominate the annual temporal variability of the ocean-induced magnetic field.

Long range surface plasmon resonance with ultra-high penetration depth for self-referenced sensing and ultra-low detection limit using diverging beam approach

Energy Technology Data Exchange (ETDEWEB)

Isaacs, Sivan, E-mail: sivan.isaacs@gmail.com; Abdulhalim, Ibrahim [Department of Electro-Optical Engineering and TheIlse Katz Institute for Nanoscale Science and Technology, Ben Gurion University of the Negev, Beer Sheva 84105 (Israel); NEW CREATE Programme, School of Materials Science and Engineering, 1 CREATE Way, Research Wing, #02-06/08, Singapore 138602 (Singapore)

2015-05-11

Using an insulator-metal-insulator structure with dielectric having refractive index (RI) larger than the analyte, long range surface plasmon (SP) resonance exhibiting ultra-high penetration depth is demonstrated for sensing applications of large bioentities at wavelengths in the visible range. Based on the diverging beam approach in Kretschmann-Raether configuration, one of the SP resonances is shown to shift in response to changes in the analyte RI while the other is fixed; thus, it can be used as a built in reference. The combination of the high sensitivity, high penetration depth and self-reference using the diverging beam approach in which a dark line is detected of the high sensitivity, high penetration depth, self-reference, and the diverging beam approach in which a dark line is detected using large number of camera pixels with a smart algorithm for sub-pixel resolution, a sensor with ultra-low detection limit is demonstrated suitable for large bioentities.

A magnetic anomaly near Tc in superconducting UPt3

International Nuclear Information System (INIS)

Shivaram, B.S.; Gannon, J.J. Jr.; Hinks, D.G.

1988-12-01

We report observation of a peak in the r.f. susceptibility of a single crystal of the heavy fermion superconductor UPt 3 . The peak occurs close to but below T c = 0.53 K. In addition our measurements in the low temperature limit (T c ) yield the magnetic field penetration depth in UPt 3 . We obtain a T 4 power law for the penetration depth parallel to the c-axis of the crystal. Based on existing calculations of the penetration depth in anisotropic superconductors we identify the order-parameter in UPt 3 as an odd-parity axial state. 19 refs., 3 figs

Regularities of magnetic field penetration into half-space in type-II superconductors

International Nuclear Information System (INIS)

Medvedev, Yu.V.; Krasnyuk, I.B.

2003-01-01

The equations, modeling the distributions of the magnetic field induction and current density in the half-space with an account of the exponential volt-ampere characteristics, are obtained. The velocity of the magnetization front propagation by the assigned average rate of the change by the time of the external magnetic field at the sample boundary is determined. The integral condition for the electric resistance, nonlinearly dependent on the magnetic field, by accomplishing whereof the magnetic flux penetrates into the sample with the finite velocity is indicated. The analytical representation of the equation with the exponential boundary mode, which models the change in the magnetic field at the area boundary, is pointed out [ru

Multiscale analysis of depth-dependent soil penetration resistance in a tropical soil

Science.gov (United States)

Paiva De Lima, Renato; Santos, Djail; Medeiros Bezerra, Joel; Machado Siqueira, Glécio; Paz González, Antonio

2013-04-01

Soil penetration resistance (PR) is widely used because it is linked to basic soil properties; it is correlated to root growth and plant production and is also used as a practical tool for assessing soil compaction and to evaluate the effects of soil management. This study investigates how results from multifractal analysis can quantify key elements of depth-dependent PR profiles and how this information can be used at the field scale. We analyzed multifractality of 50 PR vertical profiles, measured from 0 to 40 cm depth and randomly located on a 6.5 ha sugar cane field in north-eastern Brazil. According to the Soil Taxonomy, the studied soil was classified as an Orthic Podsol The scaling property of each profile was typified by singularity and Rényi spectra estimated by the method of moments. The Hurst exponent was used to parameterize the autocorrelation of the vertical PR data sets. Singularity and Rènyi spectra showed the vertical PR data sets exhibited a well-defined multifractal structure. Hurst exponent values were close to one indicating strong persistence in PR variation with soil depth. Also Hurst exponent was negatively and significantly correlated to coefficient of variation (CV) and skewness of the depth-dependent PR. Multifractal analysis added valuable information to describe the spatial arrangement of depth-dependent penetrometer data sets, which was not taken into account by classical statistical indices. Multifractal parameters were mapped over the experimental field and compared with mean, maximum and minimum values of PR; these maps showed the multifractal approach also may complete information provided by descriptive statistics at the field scale.

Adaptive Neuro-Fuzzy Inference System (ANFIS)-Based Models for Predicting the Weld Bead Width and Depth of Penetration from the Infrared Thermal Image of the Weld Pool

Science.gov (United States)

Subashini, L.; Vasudevan, M.

2012-02-01

Type 316 LN stainless steel is the major structural material used in the construction of nuclear reactors. Activated flux tungsten inert gas (A-TIG) welding has been developed to increase the depth of penetration because the depth of penetration achievable in single-pass TIG welding is limited. Real-time monitoring and control of weld processes is gaining importance because of the requirement of remoter welding process technologies. Hence, it is essential to develop computational methodologies based on an adaptive neuro fuzzy inference system (ANFIS) or artificial neural network (ANN) for predicting and controlling the depth of penetration and weld bead width during A-TIG welding of type 316 LN stainless steel. In the current work, A-TIG welding experiments have been carried out on 6-mm-thick plates of 316 LN stainless steel by varying the welding current. During welding, infrared (IR) thermal images of the weld pool have been acquired in real time, and the features have been extracted from the IR thermal images of the weld pool. The welding current values, along with the extracted features such as length, width of the hot spot, thermal area determined from the Gaussian fit, and thermal bead width computed from the first derivative curve were used as inputs, whereas the measured depth of penetration and weld bead width were used as output of the respective models. Accurate ANFIS models have been developed for predicting the depth of penetration and the weld bead width during TIG welding of 6-mm-thick 316 LN stainless steel plates. A good correlation between the measured and predicted values of weld bead width and depth of penetration were observed in the developed models. The performance of the ANFIS models are compared with that of the ANN models.

Sub?40?fs, 1060?nm Yb?fiber laser enhances penetration depth in nonlinear optical microscopy of human skin

OpenAIRE

Balu, Mihaela; Saytashev, Ilyas; Hou, Jue; Dantus, Marcos; Tromberg, Bruce J.

2015-01-01

© 2015 The Authors. Advancing the practical utility of nonlinear optical microscopy requires continued improvement in imaging depth and contrast. We evaluated second-harmonic generation (SHG) and third-harmonic generation images from ex vivo human skin and showed that a sub-40 fs, 1060-nm Yb-fiber laser can enhance SHG penetration depth by up to 80% compared to a > 100 fs, 800 nm Ti:sapphire source. These results demonstrate the potential of fiber-based laser systems to address a key perform...

Muon-spin-rotation studies of the temperature dependence of the magnetic penetration depth in the YBa2Cu3Ox family and related compounds

International Nuclear Information System (INIS)

Zimmermann, P.; Keller, H.; Lee, S.L.; Savic, I.M.; Warden, M.; Zech, D.; Cubitt, R.; Forgan, E.M.; Kaldis, E.; Karpinski, J.; Krueger, C.

1995-01-01

A systematic muon-spin-rotation (μ + SR) study is presented of the temperature dependence of the London penetration depth in sintered powder samples of the YBa 2 Cu 3 O x system and related compounds. The in-plane penetration depth λ ab is estimated from the μ + SR depolarization rate of Bi 2 Sr 2 CaCu 2 O 8+δ , YBa 2 Cu 4 O 8 , and a series of samples of the YBa 2 Cu 3 O x family, respectively. It is found that not only the low-temperature value λ ab (0), but also the temperature behavior λ ab (T) is specific to each compound. The form of λ ab (T) can be well characterized by a simple power law. In particular, the YBa 2 Cu 3 O x family shows a systematic variation of the form of λ ab (T) with the oxygen content x which points to a varying coupling strength, whereas λ ab (0) as a function of x suggests a positive charge transfer into the CuO 2 planes with increasing oxygen doping. Furthermore, our data is consistent with an empirical ansatz which has been proposed in the framework of a Bose-gas picture of high-temperature superconductivity. As a consequence, the pressure and the isotope coefficients can be extracted from the μ + SR depolarization rate and compared to direct measurements of these quantities, showing good agreement. Moreover, in the Bose-gas picture the variation of λ ab (T) in the YBa 2 Cu 3 O x family may be interpreted as a crossover from a dense (high-T c ) to a dilute (low-T c ) system of weakly interacting local pairs

Measurement of the London penetration depths in YBa2Cu3Ox by means of muon spin rotation (μ SR) experiments

International Nuclear Information System (INIS)

Pumpin, B.; Keller, H.; Kundig, W.; Odermatt, W.; Savic, I.M.; Schneider, J.W.; Simmler, H.; Zimmermann, P.

1989-01-01

The authors report on experiments conducted to get accurate values of the London penetration depths in YBa 2 Cu 3 O x , μSR measurements were performed on a high quality, sintered sample and a c-axis-oriented polycrystal. For the sintered sample the temperature dependence of the effective penetration depthλ eff is well described by the two-fluid model, withλ eff (0) = 155(10) nm. This behavior ofλ eff (T) is consistent with conventional s-wave pairing. The anisotropy ratioλ c /λ ab ≅5(1) was determined from measurements on the polycrystal. These results were used to calculateλ ab (0) = 130(10) nm andλ c (0)≅ 500-800 nm

Determination of Penetration Depth of 800 keV Electron Beam into Coal Fired Power Plant Flue Gas at in a Electron Beam Machine Flue Gas Treatment System

International Nuclear Information System (INIS)

Rany Saptaaji

2008-01-01

Penetration depth calculation of 800 keV electron beam into flue gas from coal fired power plan is presented in this paper. Electron Beam for Flue Gas Treatment (EB-FGT) is a dry treatment process using electron beam to simultaneously reduce SO 2 and NO x . Flue gas irradiation produces active radicals and then reaction with SO 2 and NO x produces nitrate acid and sulphate acid. Process vessel is needed in this process as reaction container of flue gas with electron beam. The calculation of electron beam penetration depth into flue gas is used to determine the process vessel dimension. The result of calculation of optimum penetration depth of 800 keV electron beam into flue gas is 188.67 cm. (author)

Evaluation of the Effective Moisture Penetration Depth Model for Estimating Moisture Buffering in Buildings

Energy Technology Data Exchange (ETDEWEB)

Woods, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Winkler, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Christensen, D. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-01-01

This study examines the effective moisture penetration depth (EMPD) model, and its suitability for building simulations. The EMPD model is a compromise between the simple, inaccurate effective capacitance approach and the complex, yet accurate, finite-difference approach. Two formulations of the EMPD model were examined, including the model used in the EnergyPlus building simulation software. An error in the EMPD model we uncovered was fixed with the release of EnergyPlus version 7.2, and the EMPD model in earlier versions of EnergyPlus should not be used.

Magnetic Field Effects and Electromagnetic Wave Propagation in Highly Collisional Plasmas.

Science.gov (United States)

Bozeman, Steven Paul

The homogeneity and size of radio frequency (RF) and microwave driven plasmas are often limited by insufficient penetration of the electromagnetic radiation. To investigate increasing the skin depth of the radiation, we consider the propagation of electromagnetic waves in a weakly ionized plasma immersed in a steady magnetic field where the dominant collision processes are electron-neutral and ion-neutral collisions. Retaining both the electron and ion dynamics, we have adapted the theory for cold collisionless plasmas to include the effects of these collisions and obtained the dispersion relation at arbitrary frequency omega for plane waves propagating at arbitrary angles with respect to the magnetic field. We discuss in particular the cases of magnetic field enhanced wave penetration for parallel and perpendicular propagation, examining the experimental parameters which lead to electromagnetic wave propagation beyond the collisional skin depth. Our theory predicts that the most favorable scaling of skin depth with magnetic field occurs for waves propagating nearly parallel to B and for omega << Omega_{rm e} where Omega_{rm e} is the electron cyclotron frequency. The scaling is less favorable for propagation perpendicular to B, but the skin depth does increase for this case as well. Still, to achieve optimal wave penetration, we find that one must design the plasma configuration and antenna geometry so that one generates primarily the appropriate angles of propagation. We have measured plasma wave amplitudes and phases using an RF magnetic probe and densities using Stark line broadening. These measurements were performed in inductively coupled plasmas (ICP's) driven with a standard helical coil, a reverse turn (Stix) coil, and a flat spiral coil. Density measurements were also made in a microwave generated plasma. The RF magnetic probe measurements of wave propagation in a conventional ICP with wave propagation approximately perpendicular to B show an increase in

Measuring penetration depth of electron beam welds. Final report

International Nuclear Information System (INIS)

Hill, J.W.; Collins, M.C.; Mentesana, C.P.; Watterson, C.E.

1975-07-01

The feasibility of evaluating electron beam welds using state-of-the-art techniques in the fields of holographic interferometry, micro-resistance measurements, and heat transfer was studied. The holographic study was aimed at evaluating weld defects by monitoring variations in weld strength under mechanical stress. The study, along with successful work at another facility, proved the feasibility of this approach for evaluating welds, but it did not assign any limitations to the technique. The micro-resistance study was aimed at evaluating weld defects by measuring the electrical resistance across the weld junction as a function of distance along the circumference. Experimentation showed this method, although sensitive, is limited by the same factors affecting other conventional nondestructive tests. Nevertheless, it was successful at distinguishing between various depths of penetration. It was also shown to be a sensitive thickness gage for thin-walled parts. The infrared study was aimed at evaluating weld defects by monitoring heat transfer through the weld under transient thermal conditions. Experimentation showed that this theoretically sound technique is not workable with the infrared equipment currently available at Bendix Kansas City. (U.S.)

Photon penetration depth in human brain for light stimulation and treatment: A realistic Monte Carlo simulation study

Directory of Open Access Journals (Sweden)

Ting Li

2017-09-01

Full Text Available Light has been clinically utilized as a stimulation in medical treatment, such as Low-level laser therapy and photodynamic therapy, which has been more and more widely accepted in public. The penetration depth of the treatment light is important for precision treatment and safety control. The issue of light penetration has been highlighted in biomedical optics field for decades. However, quantitative research is sparse and even there are conflicts of view on the capability of near-infrared light penetration into brain tissue. This study attempts to quantitatively revisit this issue by innovative high-realistic 3D Monte Carlo modeling of stimulated light penetration within high-precision Visible Chinese human head. The properties of light, such as its wavelength, illumination profile and size are concern in this study. We made straightforward and quantitative comparisons among the effects by the light properties (i.e., wavelengths: 660, 810 and 980nm; beam types: Gaussian and flat beam; beam diameters: 0, 2, 4 and 6cm which are in the range of light treatment. The findings include about 3% of light dosage within brain tissue; the combination of Gaussian beam and 810nm light make the maximum light penetration (>5cm, which allows light to cross through gray matter into white mater. This study offered us, the first time as we know, quantitative guide for light stimulation parameter optimization in medical treatment.

Microwave study of magnetic field penetration parallel to thin niobium films

International Nuclear Information System (INIS)

Grbic, M.S.; Janjusevic, D.; Pozek, M.; Dulcic, A.; Wagner, T.

2007-01-01

Complex conductivity of high quality niobium thin films has been investigated by microwave technique in parallel static magnetic field. For the 40 nm thick film no vortices can be formed and the microwave penetration is defined by the strength of the superconducting order parameter which varies with the applied magnetic field. 160 nm thick measured film allows formation of two rows of vortices. Microwave dissipiation is dominated by dynamics of vortices which is strongly affected by size effects. Results have been compared with the generalised models of complex conductivity for low-dimensional superconductor in mixed state following earlier considerations by other authors

Performance of Magnetic Penetration Thermometers for X-Ray Astronomy

Science.gov (United States)

Nagler, P. C.; Adams, J. S.; Balvin, M. A.; Bandler, S. R.; Denis, K. L.; Hsieh, W. T.; Kelly, D. P.; Porst, J. P.; Sadleir, J. E.; Seidel, G. M.;

Effect of tool rotational speed and penetration depth on dissimilar aluminum alloys friction stir spot welds

Directory of Open Access Journals (Sweden)

Joaquín M. Piccini

2017-03-01

Full Text Available In the last years, the automotive industry is looking for the use of aluminum parts in replace of steel parts in order to reduce the vehicles weight. These parts have to be joined, for instance, by welding processes. The more common welding process in the automotive industry is the Resistance Spot Welding (RSW technique. However, RSW of aluminum alloys has many disadvantages. Regarding this situation, a variant of the Friction Stir Welding process called Friction Stir Spot Welding (FSSW has been developed, showing a strong impact in welding of aluminum alloys and dissimilar materials in thin sheets. Process parameters affect the characteristics of the welded joints. However, the information available on this topic is scarce, particularly for dissimilar joints and thin sheets. The aim of this work was to study the effect of the rotational speed and the tool penetration depth on the characteristics of dissimilar FSS welded joints. Defects free joints have been achieved with higher mechanical properties than the ones reported. The maximum fracture load was 5800 N. It was observed that the effective joint length of the welded spots increased with the tool penetration depth, meanwhile the fracture load increased and then decreased. Finally, welding at 1200 RPM produced welded joints with lower mechanical properties than the ones achieved at 680 and 903 RPM.

Improving Keyhole Stability by External Magnetic Field in Full Penetration Laser Welding

Science.gov (United States)

Li, Min; Xu, Jiajun; Huang, Yu; Rong, Youmin

2018-05-01

An external magnetic field was used to improve the keyhole stability in full penetration laser welding 316L steel. The increase of magnetic field strength gave rise to a shorter flying time of the spatter, a weaker size and brightness of the spatter, and a larger spreading area of vapor plume. This suggested that the dynamic behavior of the keyhole was stabilized by the external magnetic field. In addition, a stronger magnetic field could result in a more homogeneous distribution of laser energy, which increased the width of the weld zone, and the height of the bottom weld zone from 381 μm (0 mT) to 605 μm (50 mT). Dendrite and cellular crystal near the weld center disappeared, and grain size was refined. The external magnetic field was beneficial to the keyhole stability and improved the joint quality, because the weld pool was stirred by a Lorentz force resulting from the coupling effect of the magnetic field and inner thermocurrent.

Controlling Force and Depth in Friction Stir Welding

Science.gov (United States)

Adams, Glynn; Loftus, Zachary; McCormac, Nathan; Venable, Richard

2005-01-01

Feedback control of the penetration force applied to a pin tool in friction stir welding has been found to be a robust and reliable means for controlling the depth of penetration of the tool. This discovery has made it possible to simplify depth control and to weld with greater repeatability, even on workpieces with long weld joints. Prior to this discovery, depths of penetration in friction stir welding were controlled by hard-tooled roller assemblies or by depth actuators controlled by feedback from such external sensors as linear variable-differential transformers or laser-based devices. These means of control are limited: A hard-tooled roller assembly confines a pin tool to a preset depth that cannot be changed easily during the welding process. A measurement by an external sensor is only an indirect indicative of the depth of penetration, and computations to correlate such a measurement with a depth of penetration are vulnerable to error. The present force-feedback approach exploits the proportionality between the depth and the force of penetration Unlike a depth measurement taken by an external sensor, a force measurement can be direct because it can be taken by a sensor coupled directly to the pin tool. The reading can be processed through a modern electronic servo control system to control an actuator to keep the applied penetration force at the desired level. In comparison with the older depth-control methods described above, this method offers greater sensitivity to plasticizing of the workpiece metal and is less sensitive to process noise, resulting in a more consistent process. In an experiment, a tapered panel was friction stir welded while controlling the force of penetration according to this method. The figure is a plot of measurements taken during the experiment, showing that force was controlled with a variation of 200 lb (890 N), resulting in control of the depth of penetration with a variation of 0.004 in. (0.1 mm).

Ground-Penetrating-Radar Profiles of Interior Alaska Highways: Interpretation of Stratified Fill, Frost Depths, Water Table, and Thaw Settlement over Ice-Rich Permafrost

Science.gov (United States)

2016-08-01

along either massive ice surfaces or within sections of segregated ice. The uninsulated ice surface at Tok in Figure 17B is irregular. All of the...ER D C/ CR RE L TR -1 6- 14 ERDC’s Center-Directed Research Program Ground -Penetrating-Radar Profiles of Interior Alaska Highways...August 2016 Ground -Penetrating-Radar Profiles of Interior Alaska Highways Interpretation of Stratified Fill, Frost Depths, Water Table, and Thaw

Deep ocean model penetrator experiments

International Nuclear Information System (INIS)

Freeman, T.J.; Burdett, J.R.F.

1986-01-01

Preliminary trials of experimental model penetrators in the deep ocean have been conducted as an international collaborative exercise by participating members (national bodies and the CEC) of the Engineering Studies Task Group of the Nuclear Energy Agency's Seabed Working Group. This report describes and gives the results of these experiments, which were conducted at two deep ocean study areas in the Atlantic: Great Meteor East and the Nares Abyssal Plain. Velocity profiles of penetrators of differing dimensions and weights have been determined as they free-fell through the water column and impacted the sediment. These velocity profiles are used to determine the final embedment depth of the penetrators and the resistance to penetration offered by the sediment. The results are compared with predictions of embedment depth derived from elementary models of a penetrator impacting with a sediment. It is tentatively concluded that once the resistance to penetration offered by a sediment at a particular site has been determined, this quantity can be used to sucessfully predict the embedment that penetrators of differing sizes and weights would achieve at the same site

Sub-40 fs, 1060-nm Yb-fiber laser enhances penetration depth in nonlinear optical microscopy of human skin

Science.gov (United States)

Balu, Mihaela; Saytashev, Ilyas; Hou, Jue; Dantus, Marcos; Tromberg, Bruce J.

2015-12-01

Advancing the practical utility of nonlinear optical microscopy requires continued improvement in imaging depth and contrast. We evaluated second-harmonic generation (SHG) and third-harmonic generation images from ex vivo human skin and showed that a sub-40 fs, 1060-nm Yb-fiber laser can enhance SHG penetration depth by up to 80% compared to a >100 fs, 800 nm Ti:sapphire source. These results demonstrate the potential of fiber-based laser systems to address a key performance limitation related to nonlinear optical microscopy (NLOM) technology while providing a low-barrier-to-access alternative to Ti:sapphire sources that could help accelerate the movement of NLOM into clinical practice.

Neutron reflectometry as a tool to study magnetism

International Nuclear Information System (INIS)

Felcher, G. P.

1999-01-01

Polarized-neutron specular reflectometry (PNR) was developed in the 1980's as a means of measuring magnetic depth profiles in flat films. Starting from simple profiles, and gradually solving structures of greater complexity, PNR has been used to observe or clarify a variety of magnetic phenomena. It has been used to measure the absolute magnetization of films of thickness not exceeding a few atomic planes, the penetration of magnetic fields in micron-thick superconductors, and the detailed magnetic coupling across non-magnetic spacers in multilayers and superlattices. Although PNR is considered a probe of depth dependent magnetic structure, laterally averaged in the plane of the film, the development of new scattering techniques promises to enable the characterization of lateral magnetic structures. Retaining the depth-sensitivity of specular reflectivity, off-specular reflectivity may be brought to resolve in-plane structures over nanometer to micron length scales

Influence of planar macrodefects on the anisotropy of magnetic-flux penetration in YBa 2Cu 3O 7-δ

Science.gov (United States)

Cuche, E.; Indenbom, M. V.; André, M.-O.; Richard, P.; Benoit, W.; Wolf, Th.

1996-02-01

The magnetic flux penetration in a high-quality YBa 2Cu 3O 7-δ single crystal with an external field applied perpendicular to the crystalline c axis is directly visualized by means of the magneto-optical technique. The observations show that the field penetrates preferentially along the ab planes. Scanning acoustic microscopy reveals macrodefects along ab planes which strongly affect this anisotropy of the field penetration.

A simple accurate chest-compression depth gauge using magnetic coils during cardiopulmonary resuscitation.

Science.gov (United States)

Kandori, Akihiko; Sano, Yuko; Zhang, Yuhua; Tsuji, Toshio

2015-12-01

This paper describes a new method for calculating chest compression depth and a simple chest-compression gauge for validating the accuracy of the method. The chest-compression gauge has two plates incorporating two magnetic coils, a spring, and an accelerometer. The coils are located at both ends of the spring, and the accelerometer is set on the bottom plate. Waveforms obtained using the magnetic coils (hereafter, "magnetic waveforms"), which are proportional to compression-force waveforms and the acceleration waveforms were measured at the same time. The weight factor expressing the relationship between the second derivatives of the magnetic waveforms and the measured acceleration waveforms was calculated. An estimated-compression-displacement (depth) waveform was obtained by multiplying the weight factor and the magnetic waveforms. Displacements of two large springs (with similar spring constants) within a thorax and displacements of a cardiopulmonary resuscitation training manikin were measured using the gauge to validate the accuracy of the calculated waveform. A laser-displacement detection system was used to compare the real displacement waveform and the estimated waveform. Intraclass correlation coefficients (ICCs) between the real displacement using the laser system and the estimated displacement waveforms were calculated. The estimated displacement error of the compression depth was within 2 mm (compression gauge, based on a new calculation method, provides an accurate compression depth (estimation error < 2 mm).

Radiation and penetration matrix elements for magnetic quadrupole transitions between Nilsson states in odd nuclei

International Nuclear Information System (INIS)

Feresin, A.P.; Guseva, I.S.

1984-01-01

Single-particle matrix elements for magnetic quadrupole gamma radiation in odd deformed nuclei, calculated with the aid of Nilsson-potential wave functions, are presented. Also given are the internal conversion penetration matrix elements, calculated in the same manner. The penetration matrix elements are needed to estimate the nuclear penetration parameter, which determines the deviation of experimental internal conversion coefficients from their standard values given in tables. Matrix elements are given for transitions between all pairs of Nilsson single-particle states with ΔN = 1 and ΔK = 0, 1, and 2 for the nuclear shells with 4< or =N< or =7 and for the two deformation values epsilon = 0.2 and 0.3

An investigation into the depth of penetration of low level laser therapy through the equine tendon in vivo

Directory of Open Access Journals (Sweden)

Ryan Teresa

2007-05-01

Full Text Available Abstract Low level laser therapy (LLLT is frequently used in the treatment of wounds, soft tissue injury and in pain management. The exact penetration depth of LLLT in human tissue remains unspecified. Similar uncertainty regarding penetration depth arises in treating animals. This study was designed to test the hypothesis that transmission of LLLT in horses is increased by clipping the hair and/or by cleaning the area to be treated with alcohol, but is unaffected by coat colour. A LLLT probe (810 nm, 500 mW was applied to the medial aspect of the superficial flexor tendon of seventeen equine forelimbs in vivo. A light sensor was applied to the lateral aspect, directly opposite the laser probe to measure the amount of light transmitted. Light transmission was not affected by individual horse, coat colour or leg. However, it was associated with leg condition (F = 4.42, p = 0.0032. Tendons clipped dry and clipped and cleaned with alcohol, were both associated with greater transmission of light than the unprepared state. Use of alcohol without clipping was not associated with an increase in light transmission. These results suggest that, when applying laser to a subcutaneous structure in the horse, the area should be clipped and cleaned beforehand.

The predicting ultimate of joint withdrawal resistance constructed of plywood with regression models application according to diameter and penetrating depth

Directory of Open Access Journals (Sweden)

Sadegh Maleki

2013-11-01

Full Text Available The goal of this study was to present regression models for predicting resistance of joints made with screw and plywood members. Joint members were out of hardwood plywood that were 19 mm in thickness. Two types of screws including coarse and fine thread drywall screw with 3.5, 4 and 5mm in diameter and sheet metal screw with 4 and 5mm were used. Results have shown that withdrawal resistance of screw was increased by increasing of screws, diameter and penetrating depth. Joints fabricated with coarse thread drywall screws were higher than those of fine thread drywall screws. Finally, average joint withdrawal resistance of screwed could be predicted by means of the expressions Wc=2.127×D1.072×P0.520 for coarse thread drywall screws and Wf=1.377×D1.156×P0.581 for fine thread drywall screws by taking account the diameter and penetrating depth. The difference of the observed and predicted data showed that developed models have a good correlation with actual experimental measurements.

Three-dimensional simulation study of compact toroid injection into magnetized plasmas

International Nuclear Information System (INIS)

Yoshio Suzuki; Tomohiko Watanabe; Tetsuya Sato; Takaya Hayashi

1999-01-01

Three-dimensional dynamics of a compact toroid (CT), which is injected into a magnetized target plasma modeling a part of a fusion device is investigated by using magnetohydrodynamic numerical simulations. It is found that the injected CT penetrates into the device region, suffering from a tilting instability. In this process, magnetic reconnection between the CT magnetic field and the device magnetic field takes place, which disrupts the magnetic configuration of the CT. As a result, the high density plasma confined in the CT magnetic field is locally supplied in the device region. Furthermore, the authors examine the penetration depth of the CT high density plasma. And it is revealed that the CT high density plasma is decelerated by the device magnetic field through the compressional heating

Photothermal investigation of local and depth dependent magnetic properties

International Nuclear Information System (INIS)

Pelzl, J; Meckenstock, R

2010-01-01

To achieve a spatially resolved measurement of magnetic properties two different photothermal approaches are used which rely on heat dissipated by magnetic resonance absorption or thermal modulation of the magnetic properties, respectively. The heat produced by modulated microwave absorption is detected by the classical photothermal methods such as photoacoustic effect and mirage effect. Examples comprise depth resolution of the magnetization of layered tapes and visualisation of magnetic excitations in ferrites. The second photothermal technique relies on the local modulation of magnetic properties by a thermal wave generated with an intensity modulated laser beam incident on the sample. This technique has a higher spatial resolution and sensitivity and has been used to characterize lateral magnetic properties of multilayers and spintronic media. To extend the lateral resolution of the ferromagnetic resonance detection into the nm-range techniques have been developed which are based on the detection of the modulated thermal microwave response by the thermal probe of an atomic force microscope (AFM) or by detection the thermal expansion of the magnetic sample in the course of the resonant microwave absorption with an AFM or tunnelling microscope. These thermal near field based techniques in ferromagnetic resonance have been successfully applied to image magnetic inhomogeneities around nano-structures and to measure the ferromagnetic resonance from magnetic nano-dots.

Sphere impact and penetration into wet sand

KAUST Repository

Marston, J. O.

2012-08-07

We present experimental results for the penetration of a solid sphere when released onto wet sand. We show, by measuring the final penetration depth, that the cohesion induced by the water can result in either a deeper or shallower penetration for a given release height compared to dry granular material. Thus the presence of water can either lubricate or stiffen the granular material. By assuming the shear rate is proportional to the impact velocity and using the depth-averaged stopping force in calculating the shear stress, we derive effective viscosities for the wet granular materials.

Sphere impact and penetration into wet sand

KAUST Repository

Marston, J. O.; Vakarelski, Ivan Uriev; Thoroddsen, Sigurdur T

2012-01-01

We present experimental results for the penetration of a solid sphere when released onto wet sand. We show, by measuring the final penetration depth, that the cohesion induced by the water can result in either a deeper or shallower penetration for a given release height compared to dry granular material. Thus the presence of water can either lubricate or stiffen the granular material. By assuming the shear rate is proportional to the impact velocity and using the depth-averaged stopping force in calculating the shear stress, we derive effective viscosities for the wet granular materials.

Measurements of the London penetration depths in YBa sub 2 Cu sub 3 O sub x by means of muon spin rotation (. mu. SR) experiments

Energy Technology Data Exchange (ETDEWEB)

Puempin, B.; Keller, H.; Kuendig, W.; Odermatt, W.; Savic, I.M.; Schneider, J.W.; Simmler, H.; Zimmermann, P. (Physik-Inst., Univ. Zuerich (Switzerland)); Bednorz, J.G.; Maeno, Y.; Mueller, K.A.; Rossel, C. (IBM Research Div., Zuerich Research Lab., Rueschlikon (Switzerland)); Kaldis, E.; Rusiecki, S. (Lab. fuer Festkoerperphysik, ETH Zuerich (Switzerland)); Assmus, W.; Kowalewski, J. (Physikalisches Inst., Univ. Frankfurt (Germany, F.R.))

1989-12-01

To get accurate values of the London penetration depths in YBa{sub 2}Cu{sub 3}O{sub x}, {mu}SR measurements were performed on a high quality, sintered sample and a c-axis-oriented polycrystal. For the sintered sample the temperature dependence of the effective penetration depth {lambda}{sub eff} is well described by the two-fluid model, with {lambda}{sub eff}(0) = 155(10) nm. This behavior of {lambda}{sub eff}(T) is consistent with conventional s-wave pairing. The anisotropy ratio {lambda}{sub c}/{lambda}{sub ab} {approx equal} 5(1) was determined from measurements on the polycrystal. These results were used to calculate {lambda}{sub ab}(0) = 130(10) nm and {lambda}{sub c}(0) {approx equal} 500-800 nm. (orig.).

Miniature Ground Penetrating Radar, CRUX GPR

Science.gov (United States)

Kim, Soon Sam; Carnes, Steven R.; Haldemann, Albert F.; Ulmer, Christopher T.; Ng, Eddie; Arcone, Steven A.

2006-01-01

Under NASA instrument development programs (PIDDP 2000-2002, MIPD 2003-2005, ESR and T, 2005) we have been developing miniature ground penetrating radars (GPR) for use in mapping subsurface stratigraphy from planetary rovers for Mars and lunar applications. The Mars GPR is for deeper penetration (up to 50 m depth) into the Martian subsurface at moderate resolution (0.5 m) for a geological characterization. As a part of the CRUX (Construction and Resource Utilization Explorer) instrument suite, the CRUX GPR is optimized for a lunar prospecting application. It will have shallower penetration (5 m depth) with higher resolution (10 cm) for construction operations including ISRU (in-situ resource utilization).

London penetration depth and thermal fluctuations in the sulphur hydride 203 K superconductor

Energy Technology Data Exchange (ETDEWEB)

Talantsev, E.F.; Crump, W.P. [Robinson Research Institute, Victoria University of Wellington, Lower Hutt (New Zealand); Storey, J.G.; Tallon, J.L. [Robinson Research Institute, Victoria University of Wellington, Lower Hutt (New Zealand); MacDiarmid Institute for Advanced Materials and Nanotechnology, Lower Hutt (New Zealand)

2017-03-15

Recently, compressed H{sub 2}S has been shown to become superconducting at 203 K under a pressure of 155 GPa. One might expect fluctuations to dominate at such temperatures. Using the magnetisation critical current, we determine the ground-state London penetration depth, λ{sub 0} = 189 nm, and the superconducting energy gap, Δ{sub 0} = 27.8 meV, and find these parameters are similar to those of cuprate superconductors. We also determine the fluctuation temperature scale, T{sub fluc} = 1470 K, which shows that, unlike the cuprates, T{sub c} of the hydride is not limited by fluctuations. This is due to its three dimensionality and suggests the search for better superconductors should refocus on three-dimensional systems where the inevitable thermal fluctuations are less likely to reduce the observed T{sub c}. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Influence of structural disorder on low-temperature behavior of penetration depth in electron-doped high-TC thin films

International Nuclear Information System (INIS)

Lanfredi, A.J.C.; Sergeenkov, S.; Araujo-Moreira, F.M.

2006-01-01

To probe the influence of structural disorder on low-temperature behavior of magnetic penetration depth, λ(T), in electron-doped high-T C superconductors, a comparative study of high-quality Pr 1.85 Ce 0.15 CuO 4 (PCCO) and Sm 1.85 Ce 0.15 CuO 4 (SCCO) thin films is presented. The λ(T) profiles are extracted from conductance-voltage data using a highly-sensitive home-made mutual-inductance technique. The obtained results confirm a d-wave pairing mechanism in both samples (with nodal gap parameter Δ 0 /k B T C =2.0 and 2.1 for PCCO and SCCO films, respectively), substantially modified by impurity scattering (which is more noticeable in less homogeneous SCCO films) at the lowest temperatures. More precisely, Δλ(T)=λ(T)-λ(0) is found to follow the Goldenfeld-Hirschfeld interpolation formulae Δλ(T)/λ(0)=AT 2 /(T+T 0 ) with T 0 =ln(2)k B Γ 1/2 Δ 0 1/2 being the crossover temperature which demarcates pure and impure scattering processes (T 0 /T C =0.13 and 0.26 for PCCO and SCCO films, respectively). The value of the extracted impurity scattering rate Γ correlates with the quality of our samples and is found to be much higher in less homogeneous films with lower T C

Study of the magnetic field distribution in high-temperature superconductors using muon-spin-rotation

International Nuclear Information System (INIS)

Zimmermann, P.R.

1994-01-01

Detailed and systematic μ + SR experiments have been performed in order to (i) investigate the temperature dependence of the magnetic penetration depth in various cuprate high-T c superconductors and (ii) study the vortex structures and dynamics in the highly anisotropic Bi 2 Sr 2 CaCu 2 O 8 . The μ + SR method and its application to superconductivity has been discussed. The positive muon is a microscopic probe of the local magnetic field in the bulk of a sample. The μ + SR technique can therefore measure the magnetic field distribution p(B) which is determined by the flux structure in the superconductor. The second moment (ΔB 2 ) of p(B) is closely related to the magnetic penetration depth λ, a fundamental parameter of superconductivity. It has been shown that in high-quality sintered samples a good estimate of the in-plane penetration depth λ ab can be given in terms of the muon-depolarization rate σ. Since the penetration depth is related to the superconducting order parameter, the temperature dependence of the penetration depth is a potential probe of the pairing state. Systematic measurements of the temperature dependence of σ have been performed in sintered samples of high quality in various members of the Y123 family, Pb and Y doped Tl1212 family, and also in Y124 and Bi2212. It is found that the extracted temperature behaviour of λ ab -2 is characteristic of each compound. This can be interpreted as a varying coupling strength in these systems. In well oxygenated Y123, λ ab -2 (T) is well described by the two-fluid model indicating strong coupling. The rest of the cuprates investigated show a λ ab -2 (T) which points to weaker coupling, with λ ab -2 (T) of highly oxygen deficient Y123 being similar to the weak-coupling BCS prediction. In the Y123 family the decreasing coupling strength with decreasing oxygen content is related to the increasing anisotropy. Comparison with theoretical predictions of λ ab -2 (T) revealed that the observed

Three dimensional simulation study of spheromak injection into magnetized plasmas

International Nuclear Information System (INIS)

Suzuki, Y.; Watanabe, T.H.; Sato, T.; Hayashi, T.

2000-01-01

The three dimensional dynamics of a spheromak-like compact toroid (SCT) plasmoid, which is injected into a magnetized target plasma region, is investigated by using MHD numerical simulations. It is found that the process of SCT penetration into this region is much more complicated than that which has been analysed so far by using a conducting sphere (CS) model. The injected SCT suffers from a tilting instability, which grows with a similar timescale to that of the SCT penetration. The instability is accompanied by magnetic reconnection between the SCT magnetic field and the target magnetic field, which disrupts the magnetic configuration of the SCT. Magnetic reconnection plays a role in supplying the high density plasma, initially confined in the SCT magnetic field, to the target region. The penetration depth of the SCT high density plasma is also examined. It is shown to be shorter than that estimated from the CS model. The SCT high density plasma is decelerated mainly by the Lorentz force of the target magnetic field, which includes not only the magnetic pressure force but also the magnetic tension force. Furthermore, by comparing the SCT plasmoid injection with the bare plasmoid injection, magnetic reconnection is considered to relax the magnetic tension force, i.e. the deceleration of the SCT plasmoid. (author)

Depth to Curie temperature across the central Red Sea from magnetic data using the de-fractal method

Science.gov (United States)

Salem, Ahmed; Green, Chris; Ravat, Dhananjay; Singh, Kumar Hemant; East, Paul; Fairhead, J. Derek; Mogren, Saad; Biegert, Ed

2014-06-01

The central Red Sea rift is considered to be an embryonic ocean. It is characterised by high heat flow, with more than 90% of the heat flow measurements exceeding the world mean and high values extending to the coasts - providing good prospects for geothermal energy resources. In this study, we aim to map the depth to the Curie isotherm (580 °C) in the central Red Sea based on magnetic data. A modified spectral analysis technique, the “de-fractal spectral depth method” is developed and used to estimate the top and bottom boundaries of the magnetised layer. We use a mathematical relationship between the observed power spectrum due to fractal magnetisation and an equivalent random magnetisation power spectrum. The de-fractal approach removes the effect of fractal magnetisation from the observed power spectrum and estimates the parameters of depth to top and depth to bottom of the magnetised layer using iterative forward modelling of the power spectrum. We applied the de-fractal approach to 12 windows of magnetic data along a profile across the central Red Sea from onshore Sudan to onshore Saudi Arabia. The results indicate variable magnetic bottom depths ranging from 8.4 km in the rift axis to about 18.9 km in the marginal areas. Comparison of these depths with published Moho depths, based on seismic refraction constrained 3D inversion of gravity data, showed that the magnetic bottom in the rift area corresponds closely to the Moho, whereas in the margins it is considerably shallower than the Moho. Forward modelling of heat flow data suggests that depth to the Curie isotherm in the centre of the rift is also close to the Moho depth. Thus Curie isotherm depths estimated from magnetic data may well be imaging the depth to the Curie temperature along the whole profile. Geotherms constrained by the interpreted Curie isotherm depths have subsequently been calculated at three points across the rift - indicating the variation in the likely temperature profile with

Determination of linear defect depths from eddy currents disturbances

Science.gov (United States)

Ramos, Helena Geirinhas; Rocha, Tiago; Pasadas, Dário; Ribeiro, Artur Lopes

2014-02-01

One of the still open problems in the inspection research concerns the determination of the maximum depth to which a surface defect goes. Eddy current testing being one of the most sensitive well established inspection methods, able to detect and characterize different type of defects in conductive materials, is an adequate technique to solve this problem. This paper reports a study concerning the disturbances in the magnetic field and in the lines of current due to a machined linear defect having different depths in order to extract relevant information that allows the determination of the defect characteristics. The image of the eddy currents (EC) is paramount to understand the physical phenomena involved. The EC images for this study are generated using a commercial finite element model (FLUX). The excitation used produces a uniform magnetic field on the plate under test in the absence of defects and the disturbances due to the defects are compared with those obtained from experimental measurements. In order to increase the limited penetration depth of the method giant magnetoresistors (GMR) are used to lower the working frequency. The geometry of the excitation planar coil produces a uniform magnetic field on an area of around the GMR sensor, inducing a uniform eddy current distribution on the plate. In the presence of defects in the material surface, the lines of currents inside the material are deviated from their uniform direction and the magnetic field produced by these currents is sensed by the GMR sensor. Besides the theoretical study of the electromagnetic system, the paper describes the experiments that have been carried out to support the theory and conclusions are drawn for cracks having different depths.

Investigating automated depth modelling of archaeo-magnetic datasets

Science.gov (United States)

Cheyney, Samuel; Hill, Ian; Linford, Neil; Leech, Christopher

2010-05-01

Magnetic surveying is a commonly used tool for first-pass non-invasive archaeological surveying, and is often used to target areas for more detailed geophysical investigation, or excavation. Quick and routine processing of magnetic datasets mean survey results are typically viewed as 2D greyscale maps and the shapes of anomalies are interpreted in terms of likely archaeological structures. This technique is simple, but ignores some of the information content of the data. The data collected using dense spatial sampling with modern precise instrumentation are capable of yielding numerical estimates of the depths to buried structures, and their physical properties. The magnetic field measured at the surface is a superposition of the responses to all anomalous magnetic susceptibilities in the subsurface, and is therefore capable of revealing a 3D model of the magnetic properties. The application of mathematical modelling techniques to very-near-surface surveys such as for archaeology is quite rare, however similar methods are routinely used in regional scale mineral exploration surveys. Inverse modelling techniques have inherent ambiguity due to the nature of the mathematical "inverse problem". Often, although a good fit to the recorded values can be obtained, the final model will be non-unique and may be heavily biased by the starting model provided. Also the run time and computer resources required can be restrictive. Our approach is to derive as much information as possible from the data directly, and use this to define a starting model for inversion. This addresses both the ambiguity of the inverse problem and reduces the task for the inversion computation. A number of alternative methods exist that can be used to obtain parameters for source bodies in potential field data. Here, methods involving the derivatives of the total magnetic field are used in association with advanced image processing techniques to outline the edges of anomalous bodies more accurately

Long-rod penetration: the transition zone between rigid and hydrodynamic penetration modes

Directory of Open Access Journals (Sweden)

Jian-feng Lou

2014-06-01

Full Text Available Long-rod penetration in a wide range of velocity means that the initial impact velocity varies in a range from tens of meters per second to several kilometers per second. The long rods maintain rigid state when the impact velocity is low, the nose of rod deforms and even is blunted when the velocity gets higher, and the nose erodes and fails to lead to the consumption of long projectile when the velocity is very high due to instantaneous high pressure. That is, from low velocity to high velocity, the projectile undergoes rigid rods, deforming non-erosive rods, and erosive rods. Because of the complicated changes of the projectile, no well-established theoretical model and numerical simulation have been used to study the transition zone. Based on the analysis of penetration behavior in the transition zone, a phenomenological model to describe target resistance and a formula to calculate penetration depth in transition zone are proposed, and a method to obtain the boundary velocity of transition zone is determined. A combined theoretical analysis model for three response regions is built by analyzing the characteristics in these regions. The penetration depth predicted by this combined model is in good agreement with experimental result.

Projectile penetration into ballistic gelatin.

Science.gov (United States)

Swain, M V; Kieser, D C; Shah, S; Kieser, J A

2014-01-01

Ballistic gelatin is frequently used as a model for soft biological tissues that experience projectile impact. In this paper we investigate the response of a number of gelatin materials to the penetration of spherical steel projectiles (7 to 11mm diameter) with a range of lower impacting velocities (projectile velocity are found to be linear for all systems above a certain threshold velocity required for initiating penetration. The data for a specific material impacted with different diameter spheres were able to be condensed to a single curve when the penetration depth was normalised by the projectile diameter. When the results are compared with a number of predictive relationships available in the literature, it is found that over the range of projectiles and compositions used, the results fit a simple relationship that takes into account the projectile diameter, the threshold velocity for penetration into the gelatin and a value of the shear modulus of the gelatin estimated from the threshold velocity for penetration. The normalised depth is found to fit the elastic Froude number when this is modified to allow for a threshold impact velocity. The normalised penetration data are found to best fit this modified elastic Froude number with a slope of 1/2 instead of 1/3 as suggested by Akers and Belmonte (2006). Possible explanations for this difference are discussed. © 2013 Published by Elsevier Ltd.

Flux penetration in a ferromagnetic/superconducting bilayer

Energy Technology Data Exchange (ETDEWEB)

Adamus, Z.; Cieplak, M.Z.; Abal' Oshev, A. [Polish Acad Sci, Inst Phys, PL-02668 Warsaw, (Poland); Konczykowski, M. [CEA/DSM/DRECAM, Laboratoire des Solides Irradies, F-91191 Gif Sur Yvette, (France); Konczykowski, M. [Ecole Polytech, CNRS - UMR 7642, F-91128 Palaiseau, (France); Cheng, X.M.; Zhu, L.Y.; Chien, C.L. [Johns Hopkins Univ, Dept Phys and Astron, Baltimore, MD 21218 (United States)

2007-07-01

An array of miniature Hall sensors is used to study the magnetic flux penetration in a ferromagnetic/superconducting bilayer consisting of Nb as a superconducting layer and Co/Pt multilayer with perpendicular magnetic anisotropy as a ferromagnetic layer, separated by an amorphous Si layer to avoid the proximity effect. It is found that the magnetic domains in the ferromagnetic layer create a large edge barrier in the superconducting layer which delays flux penetration. The smooth flux profiles observed in the absence of magnetic pinning change into terraced profiles in the presence of domains. (authors)

A new method of Curie depth evaluation from magnetic data: Theory

Science.gov (United States)

Won, I. J. (Principal Investigator)

1981-01-01

An approach to estimating the Curie point isotherm uses the classical Gauss method inverting a system of nonlinear equations. The method, slightly modified by a differential correction technique, directly inverts filtered Magsat data to calculate the crustal structure above the Curie depth, which is modeled as a magnetized layer of varying thickness and susceptibility. Since the depth below the layer is assumed to be nonmagnetic, the bottom of the layer is interpreted as the Curie depth. The method, once fully developed, tested, and compared with previous work by others, is to be applied to a portion of the eastern U.S. when sufficient Magsat data are accumulated for the region.

Topical administration of Tetrasodium-Mesotetraphenyl-Porphinesulfonate (TPPS): correlations between drug penetration and depth of necrosis in skin of nude mice following red light irradiation

International Nuclear Information System (INIS)

Marchesini, R.; Melloni, E.; Fava, G.

1987-01-01

The main side effect in photodynamic therapy is photosensitization of the patient's skin following systemic administration of the photosensitizing agent. In the case of superficial lesions, this problem can be avoided by topically applying the drug: in this way a local treatment can be performed. The photosensitizing properties of a 2% solution of TPPS (Tetrasodium-Tetraphenylpophinesulfonate) in a vehicle containing a penetration enhancer, Azone, on skin of nude mice has been tested. An aliquot of 0.1 ml/cm 2 of the solution was painted on the skin overlying an s.c. implanted NMU-1 tumor. Subsequently, animals were sacrificed at different times after applications. Fluorescence microscopy revealed that TPPS penetration depth was related to time elapsed after application and to painting modalities. Solution penetration was enhanced by wiping with ether immediately before painting. Irradiation at 80 mW/cm 2 for 20 min with a dye laser emitting at 640 nm, 4 h after TPPS applications, produced necrosis of the upper skin layers, up to 0.2 mm in depth. These findings suggest that topical TPPS administration, followed by laser irradiation, may be a suitable treatment modality for skin lesions involving epithelial layers, even though several aspects of this methodology need further investigation

The effect of snow/sea ice type on the response of albedo and light penetration depth (e-folding depth to increasing black carbon

Directory of Open Access Journals (Sweden)

A. A. Marks

2014-09-01

Full Text Available The optical properties of snow/sea ice vary with age and by the processes they were formed, giving characteristic types of snow and sea ice. The response of albedo and light penetration depth (e-folding depth to increasing mass ratio of black carbon is shown to depend on the snow and sea ice type and the thickness of the snow or sea ice. The response of albedo and e-folding depth of three different types of snow (cold polar snow, wind-packed snow and melting snow and three sea ice (multi-year ice, first-year ice and melting sea ice to increasing mass ratio of black carbon is calculated using a coupled atmosphere–snow/sea ice radiative-transfer model (TUV-snow, over the optical wavelengths of 300–800 nm. The snow and sea ice types are effectively defined by a scattering cross-section, density and asymmetry parameter. The relative change in albedo and e-folding depth of each of the three snow and three sea ice types with increasing mass ratio of black carbon is considered relative to a base case of 1 ng g−1 of black carbon. The relative response of each snow and sea ice type is intercompared to examine how different types of snow and sea ice respond relative to each other. The relative change in albedo of a melting snowpack is a factor of four more responsive to additions of black carbon compared to cold polar snow over a black carbon increase from 1 to 50 ng g−1, while the relative change in albedo of a melting sea ice is a factor of two more responsive to additions of black carbon compared to multi-year ice for the same increase in mass ratio of black carbon. The response of e-folding depth is effectively not dependent on snow/sea ice type. The albedo of sea ice is more responsive to increasing mass ratios of black carbon than snow.

A new segmentation strategy for processing magnetic anomaly detection data of shallow depth ferromagnetic pipeline

Science.gov (United States)

Feng, Shuo; Liu, Dejun; Cheng, Xing; Fang, Huafeng; Li, Caifang

2017-04-01

Magnetic anomalies produced by underground ferromagnetic pipelines because of the polarization of earth's magnetic field are used to obtain the information on the location, buried depth and other parameters of pipelines. In order to achieve a fast inversion and interpretation of measured data, it is necessary to develop a fast and stable forward method. Magnetic dipole reconstruction (MDR), as a kind of integration numerical method, is well suited for simulating a thin pipeline anomaly. In MDR the pipeline model must be cut into small magnetic dipoles through different segmentation methods. The segmentation method has an impact on the stability and speed of forward calculation. Rapid and accurate simulation of deep-buried pipelines has been achieved by exciting segmentation method. However, in practical measurement, the depth of underground pipe is uncertain. When it comes to the shallow-buried pipeline, the present segmentation may generate significant errors. This paper aims at solving this problem in three stages. First, the cause of inaccuracy is analyzed by simulation experiment. Secondly, new variable interval section segmentation is proposed based on the existing segmentation. It can help MDR method to obtain simulation results in a fast way under the premise of ensuring the accuracy of different depth models. Finally, the measured data is inversed based on new segmentation method. The result proves that the inversion based on the new segmentation can achieve fast and accurate inversion of depth parameters of underground pipes without being limited by pipeline depth.

Three-dimensional simulation study of compact toroid plasmoid injection into magnetized plasmas

International Nuclear Information System (INIS)

Suzuki, Y.; Watanabe, T.-H.; Sato, T.; Hayashi, T.

1999-04-01

Three-dimensional dynamics of a compact toroid (CT) plasmoid, which is injected into a magnetized target plasma region is investigated by using magnetohydrodynamic (MHD) numerical simulations. It is found that the process of the CT penetration into this region is much more complicated than what has been analyzed so far by using a conducting sphere (CS) model. The injected CT suffers from a tilting instability, which grows with the similar time scale as the CT penetration. The instability is accompanied by magnetic reconnection between the CT magnetic field and the target magnetic field, which disrupts the magnetic configuration of the CT. Magnetic reconnection plays a role to supply the high density plasma initially confined in the CT magnetic field into the target region. Also, the penetration depth of the CT high density plasma is examined. It is shown to be shorter than that estimated from the CS model. The CT high density plasma is decelerated mainly by the Lorentz force of the target magnetic field, which includes not only the magnetic pressure force but also the magnetic tension force. Furthermore, by comparing the CT plasmoid injection with the bare plasmoid injection, magnetic reconnection is considered to relax the magnetic tension force, that is the deceleration of the CT plasmoid. (author)

The Basics of Hacking and Penetration Testing Ethical Hacking and Penetration Testing Made Easy

CERN Document Server

Engebretson, Patrick

2011-01-01

The Basics of Hacking and Penetration Testing serves as an introduction to the steps required to complete a penetration test or perform an ethical hack. You learn how to properly utilize and interpret the results of modern day hacking tools; which are required to complete a penetration test. Tool coverage will include, Backtrack Linux, Google, Whois, Nmap, Nessus, Metasploit, Netcat, Netbus, and more. A simple and clean explanation of how to utilize these tools will allow you  to gain a solid understanding of each of the four phases and prepare them to take on more in-depth texts and topi

Penetration tests to study the mechanical tribological properties of chisel type knife

Science.gov (United States)

Vlăduţoiu, L.; Chişiu, G.; Andrei, T.; Predescu, A.; Muraru, C.; Vlăduţ, V.

2017-02-01

The goal of this study was to analyze the behaviour of chisel knife type penetration in a certain type of sand. A series of penetration tests were carried out with chisel knife type, the answer to penetration depending mainly on nature, shape, size of knife and operating parameters such as speed, depth and working conditions. Tests were conducted in work conditions with wet sand and dry sand and determined force of resistance to penetration of the chisel knife type to a certain depth.

Magnetic anomaly depth and structural index estimation using different height analytic signals data

Science.gov (United States)

Zhou, Shuai; Huang, Danian; Su, Chao

2016-09-01

This paper proposes a new semi-automatic inversion method for magnetic anomaly data interpretation that uses the combination of analytic signals of the anomaly at different heights to determine the depth and the structural index N of the sources. The new method utilizes analytic signals of the original anomaly at different height to effectively suppress the noise contained in the anomaly. Compared with the other high-order derivative calculation methods based on analytic signals, our method only computes first-order derivatives of the anomaly, which can be used to obtain more stable and accurate results. Tests on synthetic noise-free and noise-corrupted magnetic data indicate that the new method can estimate the depth and N efficiently. The technique is applied to a real measured magnetic anomaly in Southern Illinois caused by a known dike, and the result is in agreement with the drilling information and inversion results within acceptable calculation error.

Magnetic-field enhancement beyond the skin-depth limit

Science.gov (United States)

Shin, Jonghwa; Park, Namkyoo; Fan, Shanhui; Lee, Yong-Hee

2010-02-01

Electric field enhancement has been actively studied recently and many metallic structures that are capable of locally enhancing electric field have been reported. The Babinet's principle can be utilized, especially in the form of Booker's extension, to transform the known electric field enhancing structures into magnetic field enhancing structures. The authors explain this transformation process and discuss the regime in which this principle breaks down. Unless the metals used can be well approximated with a PEC model, the principle's predictions fails to hold true. Authors confirm this aspect using numerical simulations based on realistic material parameters for actual metals. There is large discrepancy especially when the structural dimensions are comparable or less than the skin-depth at the wavelength of interest. An alternative way to achieve magnetic field enhancement is presented and the design of a connected bow-tie structure is proposed as an example. FDTD simulation results confirm the operation of the proposed structure.

An alternative 3D inversion method for magnetic anomalies with depth resolution

Directory of Open Access Journals (Sweden)

M. Chiappini

2006-06-01

Full Text Available This paper presents a new method to invert magnetic anomaly data in a variety of non-complex contexts when a priori information about the sources is not available. The region containing magnetic sources is discretized into a set of homogeneously magnetized rectangular prisms, polarized along a common direction. The magnetization distribution is calculated by solving an underdetermined linear system, and is accomplished through the simultaneous minimization of the norm of the solution and the misfit between the observed and the calculated field. Our algorithm makes use of a dipolar approximation to compute the magnetic field of the rectangular blocks. We show how this approximation, in conjunction with other correction factors, presents numerous advantages in terms of computing speed and depth resolution, and does not affect significantly the success of the inversion. The algorithm is tested on both synthetic and real magnetic datasets.

INTERSTELLAR MAGNETIC FIELD SURROUNDING THE HELIOPAUSE

International Nuclear Information System (INIS)

Whang, Y. C.

2010-01-01

This paper presents a three-dimensional analytical solution, in the limit of very low plasma β-ratio, for the distortion of the interstellar magnetic field surrounding the heliopause. The solution is obtained using a line dipole method that is the integration of point dipole along a semi-infinite line; it represents the magnetic field caused by the presence of the heliopause. The solution allows the variation of the undisturbed magnetic field at any inclination angle. The heliosphere is considered as having blunt-nosed geometry on the upwind side and it asymptotically approaches a cylindrical geometry having an open exit for the continuous outflow of the solar wind on the downwind side. The heliopause is treated as a magnetohydrodynamic tangential discontinuity; the interstellar magnetic field lines at the boundary are tangential to the heliopause. The interstellar magnetic field is substantially distorted due to the presence of the heliopause. The solution shows the draping of the field lines around the heliopause. The magnetic field strength varies substantially near the surface of the heliopause. The effect on the magnetic field due to the presence of the heliopause penetrates very deep into the interstellar space; the depth of penetration is of the same order of magnitude as the scale length of the heliosphere.

Fast penetration of megagauss fields into metallic conductors

International Nuclear Information System (INIS)

Schnitzer, Ory

2014-01-01

Megagauss magnetic-field penetration into a conducting material is studied via a simplified but representative model, wherein the magnetic-diffusion equation is coupled with a thermal-energy balance. The specific scenario considered is that of a prescribed magnetic field rising (in proportion to an arbitrary power r of time) at the surface of a conducting half-space whose electric conductivity is assumed proportional to an arbitrary inverse power γ of temperature. We employ a systematic asymptotic scheme in which the case of a strong surface field corresponds to a singular asymptotic limit. In this limit, the highly magnetized and hot “skin” terminates at a distinct propagating wave-front. Employing the method of matched asymptotic expansions, we find self-similar solutions of the magnetized region which match a narrow boundary-layer region about the advancing wave front. The rapidly decaying magnetic-field profile in the latter region is also self similar; when scaled by the instantaneous propagation speed, its shape is time-invariant, depending only on the parameter γ. The analysis furnishes a simple asymptotic formula for the skin-depth (i.e., the wave-front position), which substantially generalizes existing approximations. It scales with the power γr + 1∕2 of time and the power γ of field strength, and is much larger than the field-independent skin depth predicted by an athermal model. The formula further involves a dimensionless O(1) pre-factor which depends on r and γ. It is determined by solving a nonlinear eigenvalue problem governing the magnetized region. Another main result of the analysis, apparently unprecedented, is an asymptotic formula for the magnitude of the current-density peak characterizing the wave-front region. Complementary to these systematic results, we provide a closed-form but ad hoc generalization of the theory approximately applicable to arbitrary monotonically rising surface fields. Our results are in excellent agreement

Variation of energy absorption and exposure buildup factors with incident photon energy and penetration depth for boro-tellurite (B2O3-TeO2) glasses

Science.gov (United States)

Sayyed, M. I.; Elhouichet, H.

2017-01-01

The gamma ray energy absorption (EABF) and exposure buildup factors (EBF) of (100-x)TeO2-xB2O3 glass systems (where x=5, 10, 15, 20, 22.5 and 25 mol%) have been calculated in the energy region 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path). The five parameters (G-P) fitting method has been used to estimate both EABF and EBF values. Variations of EABF and EBF with incident photon energy and penetration depth have been studied. It was found that EABF and EBF values were higher in the intermediate energy region, for all the glass systems. Furthermore, boro-tellurite glass with 5 mol% B2O3, was found to present the lowest EABF and EBF values, hence it is superior gamma-ray shielding material. The results indicate that the boro-tellurite glasses can be used as radiation shielding materials.

ANTHEM simulation of the early time magnetic field penetration of the plasma surrounding a high density Z-pinch

International Nuclear Information System (INIS)

Mason, R.J.

1989-01-01

The early time penetration of magnetic field into the low density coronal plasma of a Z-pinch fiber is studied with the implicit plasma simulation code ANTHEM. Calculations show the emission of electrons from the cathode, pinching of the electron flow, magnetic insulation of the electrons near the anode, and low density ion blow off. PIC-particle ion calculations show a late time clumping of the ion density not seen with a fluid ion treatment. 4 refs., 4 figs

Lidar Penetration Depth Observations for Constraining Cloud Longwave Feedbacks

Science.gov (United States)

Vaillant de Guelis, T.; Chepfer, H.; Noel, V.; Guzman, R.; Winker, D. M.; Kay, J. E.; Bonazzola, M.

2017-12-01

Satellite-borne active remote sensing Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations [CALIPSO; Winker et al., 2010] and CloudSat [Stephens et al., 2002] provide direct measurements of the cloud vertical distribution, with a very high vertical resolution. The penetration depth of the laser of the lidar Z_Opaque is directly linked to the LongWave (LW) Cloud Radiative Effect (CRE) at Top Of Atmosphere (TOA) [Vaillant de Guélis et al., in review]. In addition, this measurement is extremely stable in time making it an excellent observational candidate to verify and constrain the cloud LW feedback mechanism [Chepfer et al., 2014]. In this work, we present a method to decompose the variations of the LW CRE at TOA using cloud properties observed by lidar [GOCCP v3.0; Guzman et al., 2017]. We decompose these variations into contributions due to changes in five cloud properties: opaque cloud cover, opaque cloud altitude, thin cloud cover, thin cloud altitude, and thin cloud emissivity [Vaillant de Guélis et al., in review]. We apply this method, in the real world, to the CRE variations of CALIPSO 2008-2015 record, and, in climate model, to LMDZ6 and CESM simulations of the CRE variations of 2008-2015 period and of the CRE difference between a warm climate and the current climate. In climate model simulations, the same cloud properties as those observed by CALIOP are extracted from the CFMIP Observation Simulator Package (COSP) [Bodas-Salcedo et al., 2011] lidar simulator [Chepfer et al., 2008], which mimics the observations that would be performed by the lidar on board CALIPSO satellite. This method, when applied on multi-model simulations of current and future climate, could reveal the altitude of cloud opacity level observed by lidar as a strong constrain for cloud LW feedback, since the altitude feedback mechanism is physically explainable and the altitude of cloud opacity accurately observed by lidar.

Effect of snow cover on soil frost penetration

Science.gov (United States)

Rožnovský, Jaroslav; Brzezina, Jáchym

2017-12-01

Snow cover occurrence affects wintering and lives of organisms because it has a significant effect on soil frost penetration. An analysis of the dependence of soil frost penetration and snow depth between November and March was performed using data from 12 automated climatological stations located in Southern Moravia, with a minimum period of measurement of 5 years since 2001, which belong to the Czech Hydrometeorological institute. The soil temperatures at 5 cm depth fluctuate much less in the presence of snow cover. In contrast, the effect of snow cover on the air temperature at 2 m height is only very small. During clear sky conditions and no snow cover, soil can warm up substantially and the soil temperature range can be even higher than the range of air temperature at 2 m height. The actual height of snow is also important - increased snow depth means lower soil temperature range. However, even just 1 cm snow depth substantially lowers the soil temperature range and it can therefore be clearly seen that snow acts as an insulator and has a major effect on soil frost penetration and soil temperature range.

A numerical study on the disturbance of explosive reactive armors to jet penetration

Directory of Open Access Journals (Sweden)

Xiang-dong Li

2014-03-01

Full Text Available The disturbance of flat and V-shaped sandwich reactive armor configurations to shaped-charge jet is studied by a numerical approach. The disturbing and cutting effects of the two reactive armor configurations to the jet are successfully captured. The predicted disturbance characteristics and patterns are in fairly good agreement with the X-ray photographic observations. The residual depth of penetration into a semi-infinitive homogeneous steel target behind the reactive armor is computed for a series of jet/armor parameters. For the flat configuration, it is demonstrated that the residual penetration depth is not significantly reduced for a normal impact while it is reduced up to 75% for an oblique impact. In comparison, the V-shaped configuration reduces the penetration depth of the jet to 90%, and it is observed that the penetration depth is not sensitive to the V-shaped angle.

Quantitative wood–adhesive penetration with X-ray computed tomography

Energy Technology Data Exchange (ETDEWEB)

Paris, Jesse L.; Kamke, Frederick A. (Oregon State U.); (Willamette Valley)

2015-09-01

Micro X-ray computed tomography (XCT) was used to analyze the 3D adhesive penetration behavior of different wood–adhesive bondlines. Three adhesives, a phenol formaldehyde (PF), a polymeric diphenylmethane diisocyanate (pMDI), and a hybrid polyvinyl acetate (PVA), all tagged with iodine for enhanced X-ray attenuation, were used to prepare single-bondline laminates in two softwoods, Douglas-fir and loblolly pine, and one hardwood, a hybrid polar. Adhesive penetration depth was measured with two separate calculations, and results were compared with 2D fluorescent micrographs. A total of 54 XCT scans were collected, representing six replicates of each treatment type; each replicate, however, consisted of approximately 1500 individual, cross-section slices stacked along the specimen length. As these adhesives were highly modified, the presented results do not indicate typical behavior for their broader adhesive classes. Still, clear penetration differences were observed between each adhesive type, and between wood species bonded with both the PF and pMDI adhesives. Furthermore, penetration results depended on the calculation method used. Two adhesive types with noticeably different resin distributions in the cured bondline, showed relatively similar penetration depths when calculated with a traditional effective penetration equation. However, when the same data was calculated with a weighted penetration calculation, which accounts for both adhesive area and depth, the results appeared to better represent the different distributions depicted in the photomicrographs and tomograms. Additionally, individual replicate comparisons showed variation due to specimen anatomy, not easily observed or interpreted from 2D images. Finally, 3D views of segmented 3D adhesive phases offered unique, in-situ views of the cured adhesive structures. In particular, voids formed by CO₂ bubbles generated during pMDI cure were clearly visible in penetrated columns of the solidified

Evaluation of carburization depth in service exposed ferritic steel using magnetic Barkhausen noise analysis

International Nuclear Information System (INIS)

Vaidyanathan, S.; Moorthy, V.; Jayakumar, T.; Baldev Raj

1996-01-01

The feasibility of using magnetic Barkhausen (MBN) measurement for the evaluation of carburization depth in ferritic steels has been reported in this paper. MBN measurements were carried out on samples from service exposed 0.5Cr-0.5Mo ferritic steel tube at different depths (cross section) from carburised ID surface to simulate the variation in carbon concentration gradient within the skin depth of MBN with increasing time of exposure to carburization. It has been observed that the MBN level increases with increasing depth of measurement. An inverse relation between MBN level and carbon content/hardness value has been observed. This study suggests that, the MBN measurements on the carburised surface can be correlated with the concentration gradient within the skin depth of the MBN which would help in predicting the approximate depth of the carburised layer with proper prior calibration. (author)

Consistent constitutive modeling of metallic target penetration using empirical, analytical, and numerical penetration models

Directory of Open Access Journals (Sweden)

John (Jack P. Riegel III

2016-04-01

Full Text Available Historically, there has been little correlation between the material properties used in (1 empirical formulae, (2 analytical formulations, and (3 numerical models. The various regressions and models may each provide excellent agreement for the depth of penetration into semi-infinite targets. But the input parameters for the empirically based procedures may have little in common with either the analytical model or the numerical model. This paper builds on previous work by Riegel and Anderson (2014 to show how the Effective Flow Stress (EFS strength model, based on empirical data, can be used as the average flow stress in the analytical Walker–Anderson Penetration model (WAPEN (Anderson and Walker, 1991 and how the same value may be utilized as an effective von Mises yield strength in numerical hydrocode simulations to predict the depth of penetration for eroding projectiles at impact velocities in the mechanical response regime of the materials. The method has the benefit of allowing the three techniques (empirical, analytical, and numerical to work in tandem. The empirical method can be used for many shot line calculations, but more advanced analytical or numerical models can be employed when necessary to address specific geometries such as edge effects or layering that are not treated by the simpler methods. Developing complete constitutive relationships for a material can be costly. If the only concern is depth of penetration, such a level of detail may not be required. The effective flow stress can be determined from a small set of depth of penetration experiments in many cases, especially for long penetrators such as the L/D = 10 ones considered here, making it a very practical approach. In the process of performing this effort, the authors considered numerical simulations by other researchers based on the same set of experimental data that the authors used for their empirical and analytical assessment. The goals were to establish a

Ethical hacking and penetration testing guide

CERN Document Server

Baloch, Rafay

2014-01-01

Requiring no prior hacking experience, Ethical Hacking and Penetration Testing Guide supplies a complete introduction to the steps required to complete a penetration test, or ethical hack, from beginning to end. You will learn how to properly utilize and interpret the results of modern-day hacking tools, which are required to complete a penetration test. The book covers a wide range of tools, including Backtrack Linux, Google reconnaissance, MetaGooFil, dig, Nmap, Nessus, Metasploit, Fast Track Autopwn, Netcat, and Hacker Defender rootkit. Supplying a simple and clean explanation of how to effectively utilize these tools, it details a four-step methodology for conducting an effective penetration test or hack.Providing an accessible introduction to penetration testing and hacking, the book supplies you with a fundamental understanding of offensive security. After completing the book you will be prepared to take on in-depth and advanced topics in hacking and penetration testing. The book walks you through each ...

Ink Penetration of Uncoated Inkjet Paper and Impact on Printing Quality

Directory of Open Access Journals (Sweden)

Ren'ai Li

2015-10-01

Full Text Available This study investigated ink penetration through imaging technology, first by gray and contour mapping and then calculating the ink penetration depth by programing. Next, a series of further analyses were carried out, including average ink permeability, ink distributions, and printability of different uncoated inkjet paper with different parameters. The impact on ink penetration of the microstructure and hydrophilicity of the uncoated paper was also studied. The experimental results indicated that paper specimens with sizing agent were resistant to the ink, resulting in a slow and shallow ink penetration. Paper containing filler had a more hydrophilic surface and porous structure, leading to a faster and deeper ink penetration. However, the calendering operation could make the paper structure more compact and reduce the porosity and penetration depth. When an appropriate combination of sizing agent, filler content, and the calendering process was utilized, a more stable hue could be produced with improvements in optical density, saturation, and color.

Depth-sensitive characterization of surface magnetic properties of as-quenched FeNbB ribbons

Czech Academy of Sciences Publication Activity Database

Životský, O.; Postava, K.; Hrabovská, K.; Hendrych, A.; Pištora, J.; Kraus, Luděk

2008-01-01

Roč. 255, č. 5 (2008), 3322- 3327 ISSN 0169-4332 R&D Projects: GA ČR GA102/08/0743 Grant - others:GA ČR(CZ) GA202/06/0531 Institutional research plan: CEZ:AV0Z10100520 Keywords : amorphous and nanocrystalline magnetic materials * magneto-optíc Kerr effect * scanning electron microscopy * depth profile Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.576, year: 2008

Two simple methods for calculating the penetration time of a longitudinal magnetic field through the wall of a metallic tube

International Nuclear Information System (INIS)

Jimenez D, H.; Colunga S, S.; Lopez C, R.; Melendez L, L.; Ramos S, J.; Cabral P, A.; Gonzalez T, L.; Chavez A, E.; Valencia A, R.

1991-06-01

Two simple and fast methods to calculate the penetration time of a longitudinal magnetic field through the wall of a long metallic tube of circular cross section are presented. The first method is based upon the proposition of an 'effective penetration thickness' given by the polar angle average of all possible straight-line transverse penetration paths of field lines through the tube wall. This method provides a quick calculation that yields a remarkably good approximation to experimental and reported values of the penetration time. In the second method the tube is considered as a RL circuit. Thus the penetration time is given by the ratio L T /R T where L T is the inductance of the tube considered as a one turn coil, and R T is the tube resistance. This method is faster to apply than the previous one but the values obtained provide only a rough approximation to the penetration time. Applications of the two methods are given for the tokamak chambers of the Japanese 'HYBTOK', the Brazilian 'TBR' and the Mexican 'Novillo'. The resulting values of the penetration time approximate very well to the reported ones in the first two cases and to the experimental one in the last. The methods are also applied to calculate the penetration time in two long tubes, one of aluminum and other of copper. Calculated values approximate very well to measured values. (Author)

Considerations on Dop (Depth Of Penetration) Test for Evaluation of Ceramics Materials Used in Ballistic Protection

Science.gov (United States)

Popa, Ioan-Dan; Dobriţa, Florin

2017-12-01

Tremendous amount of funds and other resorces were invested in studying the response of ceramic materials under ballistic impact, the main goal being to find a way to increase the protection of soldiers and the vehicles used in the modern battlespace. Using of ceramic materials especially carbon based (carbides), nitrogen based (nitrides) and oxygen based (oxides) ceramics in order to increase the protection level of ballistic equipment could be, sometimes, a big challenge when trying to use the proper test in order to evaluate and compare their performances. The role of the tests is to provide a better understanding of their response in different situations and, as a consequence, to make them more efficient as armour components through future improvements. The paper presents shortly the main tests which are used and eventually standardised for evaluating the ballistic behaviour of the ceramics and other armour components, with a special focus to DOP (Depth of Penetration) Tests.

Experimental and numerical studies on penetration of shaped charge into concrete and pebble layered targets

Directory of Open Access Journals (Sweden)

C Wang

2017-09-01

Full Text Available Experiments on penetrating into concrete and pebble layered targets were performed by shaped charge with different cone angles, liner wall thicknesses, length to diameter ratios and charge diameters at different standoffs. Based on the experimental data, the influence of shaped charge’s structural parameters on crater diameter, hole diameter, crater depth and penetration depth was analyzed in detail. Meanwhile, formation and penetration processes of all shaped charges were simulated by AUTODYN software for investigating the more intrinsic mechanisms, in which the numerical models are the same as those set up in the experiments. The results obtained in this paper indicate that there are obvious differences between jetting projectile charge (JPC and explosively formed projectile (EFP in penetrating into multi-layer targets. For the same charge diameter, the values of hole diameter formed by EFP were much larger than JPC. However, for the same standoff, the penetration depth caused by JCP were larger than EFP. The interfacial effect exists in the penetration progress of JPC.

Depth to the bottom of magnetic layer in South America and its relationship to Curie isotherm, Moho depth and seismicity behavior

Directory of Open Access Journals (Sweden)

Javier Idárraga-García

2018-01-01

After comparing our results with the Moho depths reported by other authors, we have found that the Curie isotherm is deeper than Moho in most of the South American Platform (northward to ∼20°S, which is located in the stable cratonic area at the east of the Andes. This is evidence that the lithospheric mantle here is magnetic and contributes to the long wavelength magnetic signal. Also, our results support the hypothesis that the Curie isotherm may be acting as a boundary above which most of the crustal seismicity is concentrated. Below this boundary the occurrence of seismic events decreases dramatically.

Modeling of Oblique Penetration into Geologic Targets Using Cavity Expansion Penetrator Loading with Target free-Surface Effects

Energy Technology Data Exchange (ETDEWEB)

Jung, Joe; Longcope, Donald B.; Tabbara, Mazen R.

1999-05-03

A procedure has been developed to represent the loading on a penetrator and its motion during oblique penetration into geologic media. The penetrator is modeled with the explicit dynamics, finite element computer program PRONTO 3D and the coupled pressure on the penetrator is given in a new loading option based on a separate cavity expansion (CE) solution that accounts for the pressure-reduction from a nearby target free surface. The free-surface influ- ence distance is selected in a predictive manner by considering the pressure to expand a spherical cavity in a finite radius sphere of the target material. The CE/PRONTO 3D procedure allows a detailed description of the penetrator for predicting shock environments or structural failure dur- ing the entire penetration event and is sufficiently rapid to be used in design optimization. It has been evaluated by comparing its results with data from two field tests of a full-scale penetrator into frozen soil at an impact angles of 49.6 and 52.5 degrees from the horizontal. The measured penetrator rotations were 24 and 22 degrees, respectively. In the simulation, the rotation was21 degrees and predominately resulted from the pressure reduction of the free surface. Good agree- ment was also found for the penetration depth and axial and lateral acceleration at two locations in the penetrator.

FAA Fluorescent Penetrant Laboratory Inspections

Energy Technology Data Exchange (ETDEWEB)

WINDES,CONNOR L.; MOORE,DAVID G.

2000-08-02

The Federal Aviation Administration Airworthiness Assurance NDI Validation Center currently assesses the capability of various non-destructive inspection (NDI) methods used for analyzing aircraft components. The focus of one such exercise is to evaluate the sensitivity of fluorescent liquid penetrant inspection. A baseline procedure using the water-washable fluorescent penetrant method defines a foundation for comparing the brightness of low cycle fatigue cracks in titanium test panels. The analysis of deviations in the baseline procedure will determine an acceptable range of operation for the steps in the inspection process. The data also gives insight into the depth of each crack and which step(s) of the inspection process most affect penetrant sensitivities. A set of six low cycle fatigue cracks produced in 6.35-mm thick Ti-6Al-4V specimens was used to conduct the experiments to produce sensitivity data. The results will document the consistency of the crack readings and compare previous experiments to find the best parameters for water-washable penetrant.

A Study of Crystalline Mechanism of Penetration Sealer Materials.

Science.gov (United States)

Teng, Li-Wei; Huang, Ran; Chen, Jie; Cheng, An; Hsu, Hui-Mi

2014-01-14

It is quite common to dispense a topping material like crystalline penetration sealer materials (CPSM) onto the surface of a plastic substance such as concrete to extend its service life span by surface protections from outside breakthrough. The CPSM can penetrate into the existing pores or possible cracks in such a way that it may form crystals to block the potential paths which provide breakthrough for any unknown materials. This study investigated the crystalline mechanism formed in the part of concrete penetrated by the CPSM. We analyzed the chemical composites, in order to identify the mechanism of CPSM and to evaluate the penetrated depth. As shown in the results, SEM observes the acicular-structured crystals filling capillary pores for mortar substrate of the internal microstructure beneath the concrete surface; meanwhile, XRD and FT-IR showed the main hydration products of CPSM to be C-S-H gel and CaCO₃. Besides, MIP also shows CPSM with the ability to clog capillary pores of mortar substrate; thus, it reduces porosity, and appears to benefit in sealing pores or cracks. The depth of CPSM penetration capability indicated by TGA shows 0-10 mm of sealer layer beneath the concrete surface.

London penetration depth measurements in Ba (Fe_1-xT_x)₂As₂(T=Co,Ni,Ru,Rh,Pd,Pt,Co+Cu) superconductors

Energy Technology Data Exchange (ETDEWEB)

Gordon, Ryan T. [Iowa State Univ., Ames, IA (United States)

2011-01-01

The London penetration depth has been measured in various doping levels of single crystals of Ba(Fe_1-xT_x)₂As₂ (T=Co,Ni,Ru,Rh,Pd,Pt,Co+Cu) superconductors by utilizing a tunnel diode resonator (TDR) apparatus. All in-plane penetration depth measurements exhibit a power law temperature dependence of the form Δλ_ab(T) = CTⁿ, indicating the existence of low-temperature, normal state quasiparticles all the way down to the lowest measured temperature, which was typically 500 mK. Several different doping concentrations from the Ba(Fe_1-xT_x)₂As₂ (T=Co,Ni) systems have been measured and the doping dependence of the power law exponent, n, is compared to results from measurements of thermal conductivity and specific heat. In addition, a novel method has been developed to allow for the measurement of the zero temperature value of the in-plane penetration depth, λ_ab(0), by using TDR frequency shifts. By using this technique, the doping dependence of λ_ab(0) has been measured in the Ba(Fe_1-xCo_x)₂As₂ series, which has allowed also for the construction of the doping-dependent superfluid phase stiffness, ρ_s(T) = [λ(0)/λ(T)]². By studying the effects of disorder on these superconductors using heavy ion irradiation, it has been determined that the observed power law temperature dependence likely arises from pair-breaking impurity scattering contributions, which is consistent with the proposed s±-wave symmetry of the superconducting gap in the dirty scattering limit. This hypothesis is supported by the measurement of an exponential temperature dependence of the penetration depth in the intrinsically clean LiFeAs, indicative of a nodeless superconducting gap.

Opportunities for the Reduction of Substances and Equipment Impact on Personnel in Penetrant and Magnetic Particles Testing

OpenAIRE

Yaremenko, Yuriy

2015-01-01

Penetrant testing (PT) and magnetic particles inspection (MPI) are widespread methods of non-destructive testing which are not required a lot of investments for manual application and are simple in terms of discontinuous interpretation. On the other hand, work with chemicals requires special precautions, safety instructions and disposal limitations. Growing demand among customers to decrease impact of consumables and equipment on personnel and environment, shift producers’ priorities to devel...

MAGNETIC ARC WELDING STABILIZATION USING NON-CONSUMABLE ELECTRODE

Directory of Open Access Journals (Sweden)

Павло Юрійович Сидоренко

2017-06-01

Full Text Available Results of development torch to magnetically operated   welding arc are defined. Changing the design of the electrode unit is provided the ability to create within the area of the arc magnetic field and induction given configuration without additional equipment. The features of the arc in an axial magnetic field which make it possible to avoid the welding process of unsteady abnormalities resulted in the inappropriate formation of defects in welds. Significant increase in the depth of  weld penetration is connected with the more concentrated magnetically operated   welding arc transmission energy to the product. It is concluded about the feasibility of using a designed torch for the implementation of modern technological processes non-consumable electrode welding.

Modeling of Oblique Penetration into Geologic Targets Using Cavity Expansion Penetrator Loading with Target free-Surface Effects

Energy Technology Data Exchange (ETDEWEB)

Jung, Joe; Longcope, Donald B.; Tabbara, Mazen R.

1999-06-01

A procedure has been developed to represent the loading on a penetrator and its motion during oblique penetration into geologic media. The penetrator is modeled with the explicit dynamics, finite element computer program PRONTO 3D and the coupled pressure on the penetrator is given in a new loading option based on a separate cavity expansion (CE) solution that accounts for the pressure reduction from a nearby target free surface. The free-surface influence distance is selected in a predictive manner by considering the pressure to expand a spherical cavity in a finite radius sphere of the target material. The CE/PRONTO 3D procedure allows a detailed description of the penetrator for predicting shock environments or structural failure during the entire penetra- tion event and is sufficiently rapid to be used in design optimization. It has been evaluated by comparing its results with data from two field tests of a full-scale penetrator into frozen soil at an impact angles of 49.6 and 52.5 degrees from the horizontal. The measured penetrator rotations were 24 and 22 degrees, respectively. In the simulation, the rotation was 21 degrees and predom- inately resulted from the pressure reduction of the free surface. Good agreement was also found for the penetration depth and axial and lateral acceleration at two locations in the penetrator.

Is Grey Level a Suitable Alternative to Low-Contrast Penetration as a Serial Measure of Sensitivity in Computerised Ultrasound Quality Assurance?

Science.gov (United States)

Dudley, Nicholas J; Gibson, Nicholas M

2017-02-01

The aim of this study was to test the hypothesis that grey levels are a suitable alternative measure of sensitivity in ultrasound imaging quality assurance, as there are several caveats in the use of penetration depth. In a primary cohort of nine probes, where measurements had been made for 6 to 34 mo, both penetration depth and mean grey level fell below tolerance for six probes; both penetration depth and mean grey level remained within tolerance for three probes. In a secondary cohort where a measurement programme had been in place for a shorter period, grey level and/or penetration depth fell below tolerance in 15 of 66 probes; the sensitivity and specificity of at least 10% loss of grey level in predicting >5% loss in penetration depth were 91% and 93%, respectively. A loss of grey level accompanies a loss of penetration and provides a suitable alternative measure of sensitivity. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Multi-channel ground-penetrating radar to explore spatial variations in thaw depth and moisture content in the active layer of a permafrost site

Directory of Open Access Journals (Sweden)

U. Wollschläger

2010-08-01

Full Text Available Multi-channel ground-penetrating radar (GPR was applied at a permafrost site on the Tibetan Plateau to investigate the influence of surface properties and soil texture on the late-summer thaw depth and average soil moisture content of the active layer. Measurements were conducted on an approximately 85 × 60 m² sized area with surface and soil textural properties that ranged from medium to coarse textured bare soil to finer textured, sparsely vegetated areas covered with fine, wind blown sand, and it included the bed of a gravel road. The survey allowed a clear differentiation of the various units. It showed (i a shallow thaw depth and low average soil moisture content below the sand-covered, vegetated area, (ii an intermediate thaw depth and high average soil moisture content along the gravel road, and (iii an intermediate to deep thaw depth and low to intermediate average soil moisture content in the bare soil terrain. From our measurements, we found hypotheses for the permafrost processes at this site leading to the observed late-summer thaw depth and soil moisture conditions. The study clearly indicates the complicated interactions between surface and subsurface state variables and processes in this environment. Multi-channel GPR is an operational technology to efficiently study such a system at scales varying from a few meters to a few kilometers.

Measurements of current penetration during PDX discharge start-up

International Nuclear Information System (INIS)

Meyerhofer, D.D.; Goldston, R.J.; Kaita, R.; Cavallo, A.; Grek, B.; Johnson, D.; McCune, D.C.; McGuire, K.; White, R.B.

1984-11-01

The current penetration phase of PDX discharges is examined. The Fast Ion Diagnostic Experiment has been used to measure the temporal evolution of the central q (r/a < 0.4), and to show the effect of magnetic perturbations on fast ions. During plasma current penetration, a series of magnetic perturbations was observed in the plasma. If the current was rising rapidly, the perturbations were accompanied by increases in β/sub theta/ + l/sub i//2 and decreases in the loop voltage, suggesting a rapid penetration of the plasma current. When the plasma current was rising slowly, a series of minor disruptions occurred. These were accompanied by decreases in β/sub theta/ + l/sub i//2 and the loop voltage, and increases in the plasma current. During this phase, current penetration may be enhanced by the change in the resistivity profile which accompanies the disruption

A Study of Crystalline Mechanism of Penetration Sealer Materials

Directory of Open Access Journals (Sweden)

Li-Wei Teng

2014-01-01

Full Text Available It is quite common to dispense a topping material like crystalline penetration sealer materials (CPSM onto the surface of a plastic substance such as concrete to extend its service life span by surface protections from outside breakthrough. The CPSM can penetrate into the existing pores or possible cracks in such a way that it may form crystals to block the potential paths which provide breakthrough for any unknown materials. This study investigated the crystalline mechanism formed in the part of concrete penetrated by the CPSM. We analyzed the chemical composites, in order to identify the mechanism of CPSM and to evaluate the penetrated depth. As shown in the results, SEM observes the acicular-structured crystals filling capillary pores for mortar substrate of the internal microstructure beneath the concrete surface; meanwhile, XRD and FT-IR showed the main hydration products of CPSM to be C-S-H gel and CaCO3. Besides, MIP also shows CPSM with the ability to clog capillary pores of mortar substrate; thus, it reduces porosity, and appears to benefit in sealing pores or cracks. The depth of CPSM penetration capability indicated by TGA shows 0–10 mm of sealer layer beneath the concrete surface.

Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit

Energy Technology Data Exchange (ETDEWEB)

Gilbert, DA; Grutter, AJ; Arenholz, E; Liu, K; Kirby, BJ; Borchers, JA; Maranville, BB

2016-07-22

Electric field control of magnetism provides a promising route towards ultralow power information storage and sensor technologies. The effects of magneto-ionic motion have been prominently featured in the modification of interface characteristics. Here, we demonstrate magnetoelectric coupling moderated by voltage-driven oxygen migration beyond the interface in relatively thick AlO_x/GdO_x/Co(15 nm) films. Oxygen migration and Co magnetization are quantitatively mapped with polarized neutron reflectometry under electro-thermal conditioning. The depth-resolved profiles uniquely identify interfacial and bulk behaviours and a semi-reversible control of the magnetization. Magnetometry measurements suggest changes in the microstructure which disrupt long-range ferromagnetic ordering, resulting in an additional magnetically soft phase. X-ray spectroscopy confirms changes in the Co oxidation state, but not in the Gd, suggesting that the GdO_x transmits oxygen but does not source or sink it. These results together provide crucial insight into controlling magnetism via magneto-ionic motion, both at interfaces and throughout the bulk of the films.

Penetration of ELF currents and electromagnetic fields into the Earth's equatorial ionosphere

Science.gov (United States)

Eliasson, B.; Papadopoulos, K.

2009-10-01

The penetration of extremely low frequency (ELF) transient electromagnetic fields and associated currents in the Earth's equatorial E-region plasma is studied theoretically and numerically. In the low-frequency regime, the plasma dynamics of the E-region is characterized by helicon waves since the ions are viscously coupled to neutrals while the electrons remain mobile. For typical equatorial E-region parameters, the plasma is magnetically insulated from penetration of very long timescale magnetic fields by a thin diffusive sheath. Wave penetration driven by a vertically incident pulse localized in space and time leads to both vertical penetration and the triggering of ELF helicon/whistler waves that carry currents obliquely to the magnetic field lines. The study presented here may have relevance for ELF wave generation by lightning discharges and seismic activity and can lead to new concepts in ELF/ULF injection in the earth-ionosphere waveguide.

Moessbauer study of magnetic transformation of Ni3Al-(57Co+57Fe) surface layer

International Nuclear Information System (INIS)

Dudas, J.; Zemcik, T.

1975-01-01

The results of the magnetic transformation study of the Ni 3 Al-( 57 Co+ 57 Fe) surface layer by the 57 Fe Moessbauer effect in dependence on the penetration depth of ( 57 Co+ 57 Fe) are presented. These results are discussed in terms of the magnetic polarization of the Co (and Fe) atoms and the appearance of the 'giant' magnetic moment. The critical concentration of Co+Fe impurities sufficient for transformation of the originally paramagnetic surface layer into ferromagnetic at room temperature was determined to be 1.03 at.'=.. (author)

Efficiency evaluation of ground-penetrating radar by the results of measurement of dielectric properties of soils

Energy Technology Data Exchange (ETDEWEB)

Khakiev, Zelimkhan; Kislitsa, Konstantin; Yavna, Victor [Rostov State Transport University, Rostov-on-Don (Russian Federation)

2012-12-15

The work considers the depth evaluation of ground penetrating radar (GPR) surveys using the attenuation factor of electromagnetic radiation in a medium. A method of determining the attenuation factor of low-conductive non-magnetic soils is developed based on the results of direct measurements of permittivity and conductivity of soils in the range of typical frequencies of GPR. The method relies on measuring the shift and width of the resonance line after a soil sample is being placed into a tunable cavity resonator. The advantage of this method is the preservation of soil structure during the measurement.

In vitro investigation of the follicular penetration of porcine ear skin using a nanoparticle-emulsion containing the antiseptic polihexanide In vitro investigation of the follicular penetration of porcine ear skin

Science.gov (United States)

Ulmer, M.; Patzelt, A.; Vergou, T.; Lademann, J.; Richter, H.; Kramer, A.; Müller, G.; Sterry, W.; Lange-Asschenfeldt, B.

2012-05-01

Earlier investigations regarding the distribution of the bacterial flora on the human skin demonstrate that the hair follicle acts as a bacterial reservoir, providing a quick source for secondary recontamination. These findings highlight the importance of the hair follicle as a target for modern antiseptics. In the present study, we have assessed the follicular penetration of a curcumin-labeled particle-associated antiseptic into porcine skin by laser scanning microscopy. Therefore, the follicular penetration depth of the curcumin-labeled particle-associated antiseptic was compared to the follicular penetration depth of curcumin-labeled particles without antiseptic. The investigation was performed in vitro using porcine skin biopsies. By superposition of the images acquired in the transmission and the fluorescent modus, it was possible to visualize the distribution of the fluorescent dye inside the hair follicles. Quantitative and qualitative results showed that both dispersions penetrated efficiently into the hair follicles. The average penetration depth of the particles with attached antiseptic polihexanide was significantly higher than that of particles without the attached antiseptic. Also, whilst very little sample preparation was needed, laser scanning microscopy was found to be an efficient tool to visualize the skin relief and in particular the hair follicle shaft and localize fluorescent markers within the skin tissue and hair follicles.

An energy approach study of the penetration of concrete by rigid missiles

International Nuclear Information System (INIS)

Guirgis, Sameh; Guirguis, Ehab

2009-01-01

This paper presents an energy approach for investigating the penetration of concrete by rigid missiles and the associated phenomena. However, the principal assumptions made here must be validated experimentally before giving the proposed subject further considerations. In the following, a new measure for concrete resistance to penetration by hard missiles is presented. The suggested term for this measure is 'the Volumetric Crushing Energy Density' of concrete which can be described as the energy required for converting a unit volume of concrete to separate particles under compressive loading so that the particles of the crushed volume meet certain gradation criteria. Using this quantity, an explanation of the scale effect is postulated. Moreover, a dimensionless semi-analytical formula for the penetration depth of a rigid missile in a concrete target is proposed which includes a large number of the variables of the problem. The formula assumes that the penetration incident may include several successive phases where the set of variables that governs the impact is different during each phase, and the variables that characterize the impact during each phase correlate in a different manner as well. Furthermore, many of the penetration depth formulae available in the literature are rewritten according to the formula proposed here where the concrete penetration resistance of any incident is estimated by modifying the resistance of 'reference impact incidents.' The rewritten formulae show the wide variation of the values of concrete resistance which are implicitly included in the original formulae. Finally, the proposed formula is applied using data of penetration experiments presented by Forrestal et al. [Forrestal, M.J., Altman, B.S., Cargile, J.D., Hanchak, S.J., 1994. An empirical equation for penetration depth of ogive-nose projectiles into concrete targets. Int. J. Impact Eng. 15(4), 395-405; Forrestal, M.J., Frew, D.J., Hickerson, J.P., Rohwer, T.A., 2003

Calculating depths to shallow magnetic sources using aeromagnetic data from the Tucson Basin

Science.gov (United States)

Casto, Daniel W.

2001-01-01

Using gridded high-resolution aeromagnetic data, the performance of several automated 3-D depth-to-source methods was evaluated over shallow control sources based on how close their depth estimates came to the actual depths to the tops of the sources. For all three control sources, only the simple analytic signal method, the local wavenumber method applied to the vertical integral of the magnetic field, and the horizontal gradient method applied to the pseudo-gravity field provided median depth estimates that were close (-11% to +14% error) to the actual depths. Careful attention to data processing was required in order to calculate a sufficient number of depth estimates and to reduce the occurrence of false depth estimates. For example, to eliminate sampling bias, high-frequency noise and interference from deeper sources, it was necessary to filter the data before calculating derivative grids and subsequent depth estimates. To obtain smooth spatial derivative grids using finite differences, the data had to be gridded at intervals less than one percent of the anomaly wavelength. Before finding peak values in the derived signal grids, it was necessary to remove calculation noise by applying a low-pass filter in the grid-line directions and to re-grid at an interval that enabled the search window to encompass only the peaks of interest. Using the methods that worked best over the control sources, depth estimates over geologic sites of interest suggested the possible occurrence of volcanics nearly 170 meters beneath a city landfill. Also, a throw of around 2 kilometers was determined for a detachment fault that has a displacement of roughly 6 kilometers.

Comparison of confinement in resistive-shell reversed-field pinch devices with two different magnetic shell penetration times

International Nuclear Information System (INIS)

Gravestijn, R M; Drake, J R; Hedqvist, A; Rachlew, E

2004-01-01

A loop voltage is required to sustain the reversed-field pinch (RFP) equilibrium. The configuration is characterized by redistribution of magnetic helicity but with the condition that the total helicity is maintained constant. The magnetic field shell penetration time, τ s , has a critical role in the stability and performance of the RFP. Confinement in the EXTRAP device has been studied with two values of τ s , first (EXTRAP-T2) with tau s of the order of the typical relaxation cycle timescale and then (EXTRAP-T2R) with τ s much longer than the relaxation cycle timescale, but still much shorter than the pulse length. Plasma parameters show significant improvements in confinement in EXTRAP-T2R. The typical loop voltage required to sustain comparable electron poloidal beta values is a factor of 3 lower in the EXTRAP-T2R device. The improvement is attributed to reduced magnetic turbulence

Penetrating performance and “self-sharpening” behavior of fine-grained tungsten heavy alloy rod penetrators

Energy Technology Data Exchange (ETDEWEB)

Luo, Rongmei, E-mail: luorm_1999@126.com [School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu (China); College of Equipment Engineering, Shenyang Ligong University, Shenyang 110159, Liaoning (China); Huang, Dewu; Yang, Mingchuan; Tang, Enling; Wang, Meng; He, Liping [College of Equipment Engineering, Shenyang Ligong University, Shenyang 110159, Liaoning (China)

2016-10-15

Rod penetrators with 95W–3.75Ni–1.25Fe fine-grained tungsten heavy alloy (fine-grained 95W) and conventional tungsten heavy alloy rod penetrators with the same chemical composition (conventional 95W) were subjected to ballistic impact to compare their penetration performance. “Self-sharpening” behavior and an average 10.5% increase in penetration depth compared to conventional 95W penetrators. An acute head remained on the fine-grained 95W rod with SEM results revealing many micro-cracks and small debris on surface layer of the rod head. The stress-strain curves collected in the Split Hopkinson Pressure Bar (SHPB) experiment showed that critical failure strain values of the fine-grained 95W were 0.12 and 0.39 at strain rate of 2×10{sup 3} s{sup −1} and 3.9×10{sup 3} s{sup −1}, respectively, approximately 40% and 10% lower than those of the conventional 95W. The dynamic strength values of fine-grained 95W were 2100 MPa and 2520 MPa, respectively, which were 500 MPa and 520 MPa higher than those of the conventional 95W. The relationship among microstructure, mechanical property and “self-sharpening” behavior of fine-grained 95W is discussed in this work.

Prediction of Weld Penetration in FCAW of HSLA steel using Artificial Neural Networks

International Nuclear Information System (INIS)

Asl, Y. Dadgar; Mostafa, N. B.; Panahizadeh, V. R.; Seyedkashi, S. M. H.

2011-01-01

Flux-cored arc welding (FCAW) is a semiautomatic or automatic arc welding process that requires a continuously-fed consumable tubular electrode containing a flux. The main FCAW process parameters affecting the depth of penetration are welding current, arc voltage, nozzle-to-work distance, torch angle and welding speed. Shallow depth of penetration may contribute to failure of a welded structure since penetration determines the stress-carrying capacity of a welded joint. To avoid such occurrences; the welding process parameters influencing the weld penetration must be properly selected to obtain an acceptable weld penetration and hence a high quality joint. Artificial neural networks (ANN), also called neural networks (NN), are computational models used to express complex non-linear relationships between input and output data. In this paper, artificial neural network (ANN) method is used to predict the effects of welding current, arc voltage, nozzle-to-work distance, torch angle and welding speed on weld penetration depth in gas shielded FCAW of a grade of high strength low alloy steel. 32 experimental runs were carried out using the bead-on-plate welding technique. Weld penetrations were measured and on the basis of these 32 sets of experimental data, a feed-forward back-propagation neural network was created. 28 sets of the experiments were used as the training data and the remaining 4 sets were used for the testing phase of the network. The ANN has one hidden layer with eight neurons and is trained after 840 iterations. The comparison between the experimental results and ANN results showed that the trained network could predict the effects of the FCAW process parameters on weld penetration adequately.

Energy absorption buildup factors of human organs and tissues at energies and penetration depths relevant for radiotherapy and diagnostics

DEFF Research Database (Denmark)

Manohara, S. R.; Hanagodimath, S. M.; Gerward, Leif

2011-01-01

Energy absorption geometric progression (GP) fitting parameters and the corresponding buildup factors have been computed for human organs and tissues, such as adipose tissue, blood (whole), cortical bone, brain (grey/white matter), breast tissue, eye lens, lung tissue, skeletal muscle, ovary......, testis, soft tissue, and soft tissue (4-component), for the photon energy range 0.015-15 MeV and for penetration depths up to 40 mfp (mean free path). The chemical composition of human organs and tissues is seen to influence the energy absorption buildup factors. It is also found that the buildup factor...... of human organs and tissues changes significantly with the change of incident photon energy and effective atomic number, Zeff. These changes are due to the dominance of different photon interaction processes in different energy regions and different chemical compositions of human organs and tissues...

Time-dependent behavior of magnetic fields confined by conducting walls

International Nuclear Information System (INIS)

Kidder, R.E.; Cecil, A.B.

1983-01-01

An equation is derived which describes the total current flowing in a moving conducting surface surrounding a magnetic field, where diffusion of the field into the conductor is taken into account. Analytic and numerical solutions of the current equation are obtained for the cases of exponential and linear compression of the magnetic field with time, respectively. It is assumed that the electrical conductivity is constant, that the conducting surfaces are axially symmetric, and that the thickness and radius of curvature of the conducting walls is large compared with the effective depth of penetration of the field

Penetration analysis of projectile with inclined concrete target

Directory of Open Access Journals (Sweden)

Kim S.B.

2015-01-01

Full Text Available This paper presents numerical analysis result of projectile penetration with concrete target. We applied dynamic material properties of 4340 steels, aluminium and explosive for projectile body. Dynamic material properties were measured with static tensile testing machine and Hopkinson pressure bar tests. Moreover, we used three concrete damage models included in LS-DYNA 3D, such as SOIL_CONCRETE, CSCM (cap model with smooth interaction and CONCRETE_DAMAGE (K&C concrete models. Strain rate effect for concrete material is important to predict the fracture deformation and shape of concrete, and penetration depth for projectiles. CONCRETE_DAMAGE model with strain rate effect also applied to penetration analysis. Analysis result with CSCM model shows good agreement with penetration experimental data. The projectile trace and fracture shapes of concrete target were compared with experimental data.

Penetration analysis of projectile with inclined concrete target

Science.gov (United States)

Kim, S. B.; Kim, H. W.; Yoo, Y. H.

2015-09-01

This paper presents numerical analysis result of projectile penetration with concrete target. We applied dynamic material properties of 4340 steels, aluminium and explosive for projectile body. Dynamic material properties were measured with static tensile testing machine and Hopkinson pressure bar tests. Moreover, we used three concrete damage models included in LS-DYNA 3D, such as SOIL_CONCRETE, CSCM (cap model with smooth interaction) and CONCRETE_DAMAGE (K&C concrete) models. Strain rate effect for concrete material is important to predict the fracture deformation and shape of concrete, and penetration depth for projectiles. CONCRETE_DAMAGE model with strain rate effect also applied to penetration analysis. Analysis result with CSCM model shows good agreement with penetration experimental data. The projectile trace and fracture shapes of concrete target were compared with experimental data.

Response of fractal penetration of magnetic flux to disorder landscape in superconducting films

Science.gov (United States)

Ye, Zuxin; Li, Qiang; Si, W. D.; Suenaga, M.; Solovyov, V. F.; Johnson, P. D.

2005-10-01

Magnetic flux front and induction contours in superconducting YBa2Cu3O7-δ films with defect size stilde ξ (superconducting coherence length) and s≫ξ are studied by magneto-optical imaging. Robust self-affine spatial correlation was observed using scaling analysis in the small pinning disorder-dominated ( stilde ξ) films. The roughness exponent α was determined to be ˜0.66 , independent of numbers of defects (or the film thickness). When the disorder landscape also included a distribution of large defects (s≫ξ) , the flux front and induction contours exhibited self-similarity, with a fractal dimension D determined to be ˜1.33 using the box-counting method. The remarkably different flux penetration patterns were shown to be the manifestation of self-organized criticality at different length scales.

High-velocity Penetration of Concrete Targets with Three Types of Projectiles: Experiments and Analysis

Directory of Open Access Journals (Sweden)

Shuang Zhang

Full Text Available Abstract This study conducted high-velocity penetration experiments using conventional ogive-nose, double-ogive-nose, and grooved-tapered projectiles of approximately 2.5 kg and initial velocities between 1000 and 1360 m/s to penetrate or perforate concrete targets with unconfined compressive strengths of nominally 40MPa. The penetration performance data of these three types of projectiles with two different types of materials (i.e., AerMet100 and DT300 were obtained. The crater depth model considering both the projectile mass and the initial velocity was proposed based on the test results and a theoretical analysis. The penetration ability and the trajectory stability of these three projectile types were compared and analyzed accordingly. The results showed that, under these experimental conditions, the effects of these two different kinds of projectile materials on the penetration depth and mass erosion rate of projectile were not obvious. The existing models could not reflect the crater depths for projectiles of greater weights or higher velocities, whereas the new model established in this study was reliable. The double-ogive-nose has a certain effect of drag reduction. Thus, the double-ogive-nose projectile has a higher penetration ability than the conventional ogive-nose projectile. Meanwhile, the grooved-tapered projectile has a better trajectory stability, because the convex parts of tapered shank generated the restoring moment to stabilize the trajectory.

Variation of energy absorption buildup factors with incident photon energy and penetration depth for some commonly used solvents

International Nuclear Information System (INIS)

Singh, Parjit S.; Singh, Tejbir; Kaur, Paramjeet

2008-01-01

G.P. fitting method has been used to compute energy absorption buildup factor of some commonly used solvents such as acetonitrile (C 4 H 3 N), butanol (C 4 H 9 OH), chlorobenzene (C 6 H 5 Cl), diethyl ether (C 4 H 10 O), ethanol (C 2 H 5 OH), methanol (CH 3 OH), propanol (C 3 H 7 OH) and water (H 2 O) for the wide energy range (0.015-15.0 MeV) up to the penetration depth of 10 mean free path. The variation of energy absorption buildup factor with chemical composition as well as incident photon energy for the selected solvents has been studied. It has been observed that the maximum value of energy absorption buildup factors shifts to the slightly higher incident photon energy with the increase in equivalent atomic number of the solvent and the solvent with least equivalent atomic number possesses the maximum value of energy absorption buildup factor

A simulation study of impulsive penetration of solar wind irregularities into the magnetosphere at the dayside magnetopause

International Nuclear Information System (INIS)

Ma, Z.W.; Hawkins, J.G.; Lee, L.C.

1991-01-01

A two-dimensional magnetohydrodynamic code is used to study impulsive penetration processes that occur when a plasma irregularity in the magnetosheath, modeled as a field-aligned filament, impinges on the dayside magnetopause. If the magnetic fields in the magnetosheath and magnetosphere are parallel or antiparallel, then a filament in the magnetosheath can always penetrate into the magnetosphere. However, if the fields in the magnetosheath and magnetosphere are not aligned, then a filament can only penetrate into the magnetosphere when its initial kinetic energy density exceeds the magnetic energy density attributed to the transverse component of the magnetic field by a factor of 50. In this case, the magnetospheric field lines reconnect behind the filament, thereby trapping it within the magnetosphere. Otherwise, the increasing magnetic stress in front of the filament will eventually stop the filament from further penetration. For typical parameters found at the dayside magnetopause, the threshold condition obtained from this two-dimensional model predicts that penetration is possible only when the angle between the fields is within approximately 5 of parallel or antiparallel. During the penetration process, velocity vortices are observed both inside the filament and in the external plasma. Either increased β within the magnetosphere, or the larger plasma density at the magnetopause associated with antiparallel magnetic fields, will act to reduce the penetration velocity

Eddy current testing with high penetration; WS-Pruefungen mit grosser Eindringtiefe

Energy Technology Data Exchange (ETDEWEB)

Becker, R.; Kroening, M. [Fraunhofer Inst. fuer Zerstoerungsfreie Pruefverfahren, Saarbruecken (Germany)

1999-08-01

The low-frequency eddy current testing method is used when penetration into very deep layers is required. The achievable penetration depth is determined among other parameters by the lowest testing frequency that can be realised together with the eddy current sensor. When using inductive sensors, the measuring effect declines proportional to the lowering frequency (induction effect). Further reduction of testing frequency requires other types of sensors, as e.g. the GMR (Giant Magnetic Resistance), which achieves a constant measuring sensitivity down to the steady field. The multi-frequency eddy current testing method MFEC 3 of IZFP described here can be operated using three different scanning frequencies at a time. Two variants of eddy current probes are used in this case. Both have an inductive winding at their emitters, of the type of a measuring probe. The receiver end is either also an inductive winding, or a magnetic field-responsive resistance (GMR). (orig./CB) [Deutsch] Das Niederfrequenz(NF)-Wirbelstrom(WS)-Verfahren wird eingesetzt, um eine grosse Eindringtiefe zu erzielen. Die erreichbare Tiefenreichweite wird u.a. durch die niedrigste Prueffrequenz bestimmt, die zusammen mit dem Wirbelstrom-Sensor realisiert werden kann. Bei Einsatz von induktiven Sensoren geht mit abnehmender Prueffrequenz der Messeffekt proportional zurueck (Induktionswirkung). Eine weitere Absenkung der Prueffrequenzen macht den Einsatz von andersartigen Sensoren notwendig, z.B. den GMR (Giant Magnetic Resistance), der eine gleichmaessige Messempfindlichkeit bis zum Gleichfeld besitzt. Das eingesetzte Mehrfrequenz-Wirbelstrom-Pruefverfahren MFEC 3 des IZFP arbeitet mit drei gleichzeitig eingespeisten Prueffrequenzen. Dabei werden zwei Varianten von WS-Sensoren eingesetzt. Beide besitzen auf der Senderseite eine induktive Wicklung in der Art einer Tastsonde. Die Empfaengerseite ist entweder ebenfalls eine induktive Wicklung oder ein magnetfeldempfindlicher Widerstand (GMR). (orig./DGE)

Low Force Penetration of Icy Regolith

Science.gov (United States)

Mantovani, J. G.; Galloway, G. M.; Zacny, K.

2016-01-01

A percussive cone penetrometer measures the strength of granular material by using percussion to deliver mechanical energy into the material. A percussive cone penetrometer was used in this study to penetrate a regolith ice mixture by breaking up ice and decompacting the regolith. As compared to a static cone penetrometer, percussion allows low reaction forces to push a penetrometer probe tip more easily into dry regolith in a low gravity environment from a planetary surface rover or a landed spacecraft. A percussive cone penetrates icy regolith at ice concentrations that a static cone cannot penetrate. In this study, the percussive penetrator was able to penetrate material under 65 N of down-force which could not be penetrated using a static cone under full body weight. This paper discusses using a percussive cone penetrometer to discern changes in the concentration of water-ice in a mixture of lunar regolith simulant and ice to a depth of one meter. The rate of penetration was found to be a function of the ice content and was not significantly affected by the down-force. The test results demonstrate that this method may be ideal for a small platform in a reduced gravity environment. However, there are some cases where the system may not be able to penetrate the icy regolith, and there is some risk of the probe tip becoming stuck so that it cannot be retracted. It is also shown that a percussive cone penetrometer could be used to prospect for water ice in regolith at concentrations as high as 8 by weight.

Measuring soil frost depth in forest ecosystems with ground penetrating radar

Science.gov (United States)

John R. Butnor; John L. Campbell; James B. Shanley; Stanley. Zarnoch

2014-01-01

Soil frost depth in forest ecosystems can be variable and depends largely on early winter air temperatures and the amount and timing of snowfall. A thorough evaluation of ecological responses to seasonally frozen ground is hampered by our inability to adequately characterize the frequency, depth, duration and intensity of soil frost events. We evaluated the use of...

Penetration Evaluation of Explosively Formed Projectiles Through Air and Water Using Insensitive Munition: Simulative and Experimental Studies

Directory of Open Access Journals (Sweden)

M. Ahmed

2016-02-01

Full Text Available The process of formation, flying, penetration of explosively-formed projectiles (EFP and the effect of water on performance of the charge for underwater applications is simulated by Ansysis Autodyn 2D-Hydro code. The main objective of an explosively formed projectile designed for underwater applications is to disintegrate the target at longer standoff distances. In this paper we have simulated the explosively formed projectile from OFHC-Copper liner for 1200 conical angle. The Affect of water on the penetration of EFP is determined by simulations from Ansysis Autodyn 2-D Hydrocode and by varying depth of water from 1CD-5CD. The depth of penetration against steel target is measured experimentally. Flash X-Ray Radiography (FXR is used to capture EFP jet formation and its penetration against target is measured by depth of penetration experiments. Simulation results are compared with experimental results. The difference in simulated and experimental results for depth of penetration is about 7 mm, which lies within favorable range of error. The jet formation captured from FXR is quite clear and jet velocity determined from Flash X-ray radiography is the same as the ones obtained by using other high explosives. Therefore, it is indicated that Insensitive Munition (8701 can be utilized instead of Polymer Bonded Explosives (PBX for air and underwater environments with great reliability and without any hazard.

Comparing Seismic And Magnetic Responses To Copper Gold Deposits Under Different Cover Sequences

Directory of Open Access Journals (Sweden)

Okan Evans Onojasun

2015-08-01

Full Text Available Appropriate application of geophysical techniques is required to effectively explore through the cover sequences that will allow the discovery of deep seated orebodies within the 1-3km depth range. Whilst potential field methods that are traditionally used for Cu-Au exploration seems effective they lack the expected resolution required to detect deeper mineral deposits under 500 m cover. Seismic reflection techniques offers a distinct advantage over all other geophysical techniques because of its ability to penetrate deeper into the subsurface without losing its resolution. We present in this report modelling results from magnetic and seismic responses to Cu-Au deposits when located within 100-1000m depth range. In the case of magnetic modelling we apply upward continuation filters which calculate the potential field that would have been recorded at 100m 250m 500m and 1000 m levels by filtering away shallow anomalies from the initial data. For seismic modelling simple but realistic geological model with varying cover thicknesses 100m 250m 500m and 1000m were created and then populate these models with petrophysical data. Simulated synthetic seismic responses from the models was processed using basic processing flows to obtained depth migrated images. Results show that for shower depths 0-100m good correlation exist between the magnetic and the seismic responses. From 100-250m depth cover though we can still see some magnetic anomalies within the target zone its effectiveness decreases with depths whereas seismic responses was maintain within the depth range. From 500m to 1000m magnetic response becomes spear or fuzzy as much useful information is practically missed out. Similarly high resolution power of seismic was ably demonstrated as the depth of even 2km did not degrade its resolution. Thus both magnetic and seismic methods are very useful for shallow investigation but at greater depth seismic method appears to be a more valid exploration

How has Mobile Phone Penetration Stimulated Financial Development in Africa?

OpenAIRE

Simplice A, Asongu

2012-01-01

In the first macroeconomic empirical assessment of the relationship between mobile phones and finance, this paper examines the correlations between mobile phone penetration and financial development using two conflicting definitions of the financial system in the financial development literature. With the traditional IFS (2008) definition, mobile phone penetration has a negative correlation with traditional financial intermediary dynamics of depth, activity and size. However, when a previous...

Modelling of the penetration process of externally applied helical magnetic perturbation of the DED on the TEXTOR tokamak

International Nuclear Information System (INIS)

Kikuchi, Y; Finken, K H; Jakubowski, M; Lehnen, M; Reiser, D; Sewell, G; Wolf, R C

2006-01-01

The error-field penetration process of the dynamic ergodic divertor (DED) on the TEXTOR tokamak has been investigated analytically in terms of a single fluid MHD model with a finite plasma resistivity and viscosity in a cylindrical geometry. The linear model produces a localization of the induced current at the resonance surface and predicts a vortex structure of the velocity field near the resonance layer. Moreover, effects of the Alfven resonance for the error-field penetration are identified by two peaks in the radial profiles of the perturbed toroidal current and the perturbed magnetic flux when the relative rotation velocity between the DED and the rotating tokamak plasma is set to large. Fine structures of the vorticity induced by the DED in the vicinity of the rational surface disappear by introducing a finite plasma perpendicular viscosity. In addition, it is shown that the two peaks of the perturbed toroidal current overlap by an anomalous plasma perpendicular viscosity. Likewise, a bifurcation of the penetration process from the suppressed to the excited state is obtained by a quasi-linear approach taking into account modifications of the radial profiles of the equilibrium current and the plasma rotation due to the DED. A comparison with real experimental results of the DED on the TEXTOR tokamak is shown

Melt pool and keyhole behaviour analysis for deep penetration laser welding

International Nuclear Information System (INIS)

Fabbro, R

2010-01-01

One usually defines the main characteristic of the welding performances of a given laser system by its 'penetration curve' that corresponds to the welding depth as a function of the welding speed V w for a given set of operating parameters. Analysis of a penetration curve is interesting and gives very fruitful results. Coupled with high-speed video imaging of melt pool surface and ejected plume behaviour, the analysis of this penetration curve on a very large range of welding speeds, typically from 0 to 50 m min -1 , has allowed us to observe very different and characteristic regimes. These regimes are mainly characterized by the physical processes by which they impede the laser beam penetration inside the material. We show that it is only at rather high welding speeds that these limiting processes are reduced. Consequently, the scaling law of welding depth with welding speed is in agreement with adapted modelling of this process. On the other hand, as the welding speed is reduced, different effects depending on the weld pool dynamics and plume interaction strongly disturb the keyhole stability and are responsible for the deviation of the penetration curve from the previous modelling that agrees with a 1/V w scaling law. A corresponding criterion for the occurrence of this effect is defined.

Plasma penetration depth and mechanical properties of atmospheric plasma-treated 3D aramid woven composites

International Nuclear Information System (INIS)

Chen, X.; Yao, L.; Xue, J.; Zhao, D.; Lan, Y.; Qian, X.; Wang, C.X.; Qiu, Y.

2008-01-01

Three-dimensional aramid woven fabrics were treated with atmospheric pressure plasmas, on one side or both sides to determine the plasma penetration depth in the 3D fabrics and the influences on final composite mechanical properties. The properties of the fibers from different layers of the single side treated fabrics, including surface morphology, chemical composition, wettability and adhesion properties were investigated using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), contact angle measurement and microbond tests. Meanwhile, flexural properties of the composites reinforced with the fabrics untreated and treated on both sides were compared using three-point bending tests. The results showed that the fibers from the outer most surface layer of the fabric had a significant improvement in their surface roughness, chemical bonding, wettability and adhesion properties after plasma treatment; the treatment effect gradually diminished for the fibers in the inner layers. In the third layer, the fiber properties remained approximately the same to those of the control. In addition, three-point bending tests indicated that the 3D aramid composite had an increase of 11% in flexural strength and 12% in flexural modulus after the plasma treatment. These results indicate that composite mechanical properties can be improved by the direct fabric treatment instead of fiber treatment with plasmas if the fabric is less than four layers thick

Skin pre-ablation and laser assisted microjet injection for deep tissue penetration.

Science.gov (United States)

Jang, Hun-Jae; Yeo, Seonggu; Yoh, Jack J

2017-04-01

For conventional needless injection, there still remain many unresolved issues such as the potential for cross-contamination, poor reliability of targeted delivery dose, and significantly painstaking procedures. As an alternative, the use of microjets generated with Er:YAG laser for delivering small doses with controlled penetration depths has been reported. In this study, a new system with two stages is evaluated for effective transdermal drug delivery. First, the skin is pre-ablated to eliminate the hard outer layer and second, laser-driven microjet penetrates the relatively weaker and freshly exposed epidermis. Each stage of operation shares a single Er:YAG laser that is suitable for skin ablation as well as for the generation of a microjet. In this study, pig skin is selected for quantification of the injection depth based on the two-stage procedure, namely pre-ablation and microjet injection. The three types of pre-ablation devised here consists of bulk ablation, fractional ablation, and fractional-rotational ablation. The number of laser pulses are 12, 18, and 24 for each ablation type. For fractional-rotational ablation, the fractional beams are rotated by 11.25° at each pulse. The drug permeation in the skin is evaluated using tissue marking dyes. The depth of penetration is quantified by a cross sectional view of the single spot injections. Multi-spot injections are also carried out to control the dose and spread of the drug. The benefits of a pre-ablation procedure prior to the actual microjet injection to the penetration is verified. The four possible combinations of injection are (a) microjet only; (b) bulk ablation and microjet injection; (c) fractional ablation and microjet injection; and (d) fractional-rotational ablation and microjet injection. Accordingly, the total depth increases with injection time for all cases. In particular, the total depth of penetration attained via fractional pre-ablation increased by 8 ∼ 11% and that of fractional

Standard guide for use of UV-A and visible light sources and meters used in the liquid penetrant and magnetic particle methods

CERN Document Server

American Society for Testing and Materials. Philadelphia

2004-01-01

1.1 This guide describes the use of UV-A/Visible light sources and meters used for the examination of materials by the liquid penetrant and magnetic particle processes. This guide may be used to help support the needs for appropriate light intensities and light measurement. 1.2 This guide also provides a reference: 1.2.1 To assist in the selection of light sources and meters that meet the applicable specifications or standards. 1.2.2 For use in the preparation of internal documentation dealing with liquid penetrant or magnetic particle examination of materials and parts. 1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and det...

Superconducting ring magnets of the PIOTRON Pi-meson therapy facility at SIN

Energy Technology Data Exchange (ETDEWEB)

Maix, R K; Meyer, G; Roman, T; Horvath, I; Vecsey, G; Zellweger, J

1982-01-01

Negative Pi-mesons seem to be very promising for cancer therapy, because of their well defined penetration depth and their enhanced energy deposition in the absorption region. A prototype Pi-meson therapy facility, called PIOTRON, has been constructed at SIN, where also pion beams of sufficient intensity are available. The central part of this system are two ring magnets, consisting each of 60 superconducting flat coils, with the aid of which 60 pion beams can be guided around a heavy iron shield and focused on the patient. In this paper the fabrication and the initial operation of these magnets is discussed.

Plumbing the depths of Yellowstone's hydrothermal system from helicopter magnetic and electromagnetic data

Science.gov (United States)

Finn, C.; Bedrosian, P.; Holbrook, W. S.; Auken, E.; Lowenstern, J. B.; Hurwitz, S.; Sims, K. W. W.; Carr, B.; Dickey, K.

2017-12-01

Although Yellowstone's iconic hydrothermal systems and lava flows are well mapped at the surface, their groundwater flow systems and thickness are almost completely unknown. In order to track the geophysical signatures of geysers, hot springs, mud pots, steam vents, hydrothermal explosion craters and lava flows at depths to hundreds of meters, we collected helicopter electromagnetic and magnetic (HEM) data. The data cover significant portions of the caldera including a majority of the known thermal areas. HEM data constrain electrical resistivity which is sensitive to groundwater salinity and temperature, phase distribution (liquid-vapor), and clay formed during chemical alteration of rocks. The magnetic data are sensitive to variations in the magnetization of lava flows, faults and hydrothermal alteration. The combination of electromagnetic and magnetic data is ideal for mapping zones of cold fresh water, hot saline water, steam, clay, and altered and unaltered rock. Preliminary inversion of the HEM data indicates very low resistivity directly beneath the northern part of Yellowstone Lake, intersecting with the lake bottom in close correspondence with mapped vents, fractures and hydrothermal explosion craters and are also associated with magnetic lows. Coincident resistivity and magnetic lows unassociated with mapped alteration occur, for example, along the southeast edge of the Mallard Lake dome and along the northeastern edge of Sour Creek Dome, suggesting the presence of buried alteration. Low resistivities unassociated with magnetic lows may relate to hot and/or saline groundwater or thin (<50 m) layers of early lake sediments to which the magnetic data are insensitive. Resistivity and magnetic lows follow interpreted caldera boundaries in places, yet deviate in others. In the Norris-Mammoth Corridor, NNE-SSW trending linear resistivity and magnetic lows align with mapped faults. This pattern of coincident resistivity and magnetic lows may reflect fractures

Penetration in bimodal, polydisperse granular material

KAUST Repository

Kouraytem, Nadia; Thoroddsen, Sigurdur T; Marston, J. O.

2016-01-01

We investigate the impact penetration of spheres into granular media which are compositions of two discrete size ranges, thus creating a polydisperse bimodal material. We examine the penetration depth as a function of the composition (volume fractions of the respective sizes) and impact speed. Penetration depths were found to vary between delta = 0.5D(0) and delta = 7D(0), which, for mono-modal media only, could be correlated in terms of the total drop height, H = h + delta, as in previous studies, by incorporating correction factors for the packing fraction. Bimodal data can only be collapsed by deriving a critical packing fraction for each mass fraction. The data for the mixed grains exhibit a surprising lubricating effect, which was most significant when the finest grains [d(s) similar to O(30) mu m] were added to the larger particles [d(l) similar to O(200 - 500) mu m], with a size ratio, epsilon = d(l)/d(s), larger than 3 and mass fractions over 25%, despite the increased packing fraction. We postulate that the small grains get between the large grains and reduce their intergrain friction, only when their mass fraction is sufficiently large to prevent them from simply rattling in the voids between the large particles. This is supported by our experimental observations of the largest lubrication effect produced by adding small glass beads to a bed of large sand particles with rough surfaces.

Penetration in bimodal, polydisperse granular material

KAUST Repository

Kouraytem, N.

2016-11-07

We investigate the impact penetration of spheres into granular media which are compositions of two discrete size ranges, thus creating a polydisperse bimodal material. We examine the penetration depth as a function of the composition (volume fractions of the respective sizes) and impact speed. Penetration depths were found to vary between delta = 0.5D(0) and delta = 7D(0), which, for mono-modal media only, could be correlated in terms of the total drop height, H = h + delta, as in previous studies, by incorporating correction factors for the packing fraction. Bimodal data can only be collapsed by deriving a critical packing fraction for each mass fraction. The data for the mixed grains exhibit a surprising lubricating effect, which was most significant when the finest grains [d(s) similar to O(30) mu m] were added to the larger particles [d(l) similar to O(200 - 500) mu m], with a size ratio, epsilon = d(l)/d(s), larger than 3 and mass fractions over 25%, despite the increased packing fraction. We postulate that the small grains get between the large grains and reduce their intergrain friction, only when their mass fraction is sufficiently large to prevent them from simply rattling in the voids between the large particles. This is supported by our experimental observations of the largest lubrication effect produced by adding small glass beads to a bed of large sand particles with rough surfaces.

Variation of energy absorption buildup factors with incident photon energy and penetration depth for some commonly used solvents

Energy Technology Data Exchange (ETDEWEB)

Singh, Parjit S. [Department of Physics, Punjabi University, Patiala 147 002 (India)], E-mail: dr_parjit@hotmail.com; Singh, Tejbir [Department of Physics, Lovely Professional University, Phagwara 144 402 (India); Kaur, Paramjeet [IAS and Allied Services Training Centre, Punjabi University, Patiala 147 002 (India)

2008-06-15

G.P. fitting method has been used to compute energy absorption buildup factor of some commonly used solvents such as acetonitrile (C{sub 4}H{sub 3}N), butanol (C{sub 4}H{sub 9}OH), chlorobenzene (C{sub 6}H{sub 5}Cl), diethyl ether (C{sub 4}H{sub 10}O), ethanol (C{sub 2}H{sub 5}OH), methanol (CH{sub 3}OH), propanol (C{sub 3}H{sub 7}OH) and water (H{sub 2}O) for the wide energy range (0.015-15.0 MeV) up to the penetration depth of 10 mean free path. The variation of energy absorption buildup factor with chemical composition as well as incident photon energy for the selected solvents has been studied. It has been observed that the maximum value of energy absorption buildup factors shifts to the slightly higher incident photon energy with the increase in equivalent atomic number of the solvent and the solvent with least equivalent atomic number possesses the maximum value of energy absorption buildup factor.

SHUTTLE IMAGING RADAR: PHYSICAL CONTROLS ON SIGNAL PENETRATION AND SUBSURFACE SCATTERING IN THE EASTERN SAHARA.

Science.gov (United States)

Schaber, Gerald G.; McCauley, John F.; Breed, Carol S.; Olhoeft, Gary R.

1986-01-01

It is found that the Shuttle Imaging Radar A (SIR-A) signal penetration and subsurface backscatter within the upper meter or so of the sediment blanket in the Eastern Sahara of southern Egypt and northern Sudan are enhanced both by radar sensor parameters and by the physical and chemical characteristics of eolian and alluvial materials. The near-surface stratigraphy, the electrical properties of materials, and the types of radar interfaces found to be responsible for different classes of SIR-A tonal response are summarized. The dominant factors related to efficient microwave signal penetration into the sediment blanket include 1) favorable distribution of particle sizes, 2) extremely low moisture content and 3) reduced geometric scattering at the SIR-A frequency (1. 3 GHz). The depth of signal penetration that results in a recorded backscatter, called radar imaging depth, was documented in the field to be a maximum of 1. 5 m, or 0. 25 times the calculated skin depth, for the sediment blanket. The radar imaging depth is estimated to be between 2 and 3 m for active sand dune materials.

MATLAB-based algorithm to estimate depths of isolated thin dike-like sources using higher-order horizontal derivatives of magnetic anomalies.

Science.gov (United States)

Ekinci, Yunus Levent

2016-01-01

This paper presents an easy-to-use open source computer algorithm (code) for estimating the depths of isolated single thin dike-like source bodies by using numerical second-, third-, and fourth-order horizontal derivatives computed from observed magnetic anomalies. The approach does not require a priori information and uses some filters of successive graticule spacings. The computed higher-order horizontal derivative datasets are used to solve nonlinear equations for depth determination. The solutions are independent from the magnetization and ambient field directions. The practical usability of the developed code, designed in MATLAB R2012b (MathWorks Inc.), was successfully examined using some synthetic simulations with and without noise. The algorithm was then used to estimate the depths of some ore bodies buried in different regions (USA, Sweden, and Canada). Real data tests clearly indicated that the obtained depths are in good agreement with those of previous studies and drilling information. Additionally, a state-of-the-art inversion scheme based on particle swarm optimization produced comparable results to those of the higher-order horizontal derivative analyses in both synthetic and real anomaly cases. Accordingly, the proposed code is verified to be useful in interpreting isolated single thin dike-like magnetized bodies and may be an alternative processing technique. The open source code can be easily modified and adapted to suit the benefits of other researchers.

Effect of skin tumor properties on laser penetration

CSIR Research Space (South Africa)

Karsten, AE

2009-06-01

Full Text Available Computer modeling can be a valuable tool to determine the absorption of laser light in different skin layers. For this study, the optical properties of three different skin tumors were used in the model to evaluate the effect on penetration depth...

A Novel Method for Measurements of the Penetration Depth of MgB2 Superconductor Films by Using Sapphire Resonators with Short-Circuited Parallel Plates

International Nuclear Information System (INIS)

Jung, Ho Sang; Lee, J. H.; Cho, Y. H.; Lee, Sang Young; Seong, W. K.; Lee, N. H.; Kang, W. N.

2009-01-01

We introduce a measurement method that enables to measure the penetration depth(λ) of superconductor films by using a short-ended parallel plate sapphire resonator. Variations in the (λof MgB 2 films could be measured down to the lowest temperature using a sapphire resonator with a YBa 2 Cu 3 O 7-x film at the bottom. A model equation of λλ 0 [1-(T/T c ) τ ] -1/2 for MgB 2 films appeared to describe the observed variations of the resonant frequency of the sapphire resonator with temperature, with λ 0 , τ and T c used as the fitting parameters.

Spatiotemporal Dynamics of Soil Penetration Resistance of Recultivated Soil

Directory of Open Access Journals (Sweden)

Zadorozhnaya Galina

2018-03-01

Full Text Available This article examines changes in the spatial distribution of soil penetration resistance in ordinary chernozem (Calcic Chernozem and in the recultivated soil in 2012 and 2014. The measurements were carried out in the field using an Eijkelkamp penetrometer on a regular grid. The depth of measurement was 50 cm, the interval was 5 cm. The indices of variation of soil penetration resistance in space and time have been determined. The degree of spatial dependence of soil penetration resistance has been determined layer by layer. The nature of temporal dynamics of soil penetration resistance of chernozem and technical soil has been described. A significant positive relationship of the structure of chernozem in the two years of the research has been shown. Significant correlations between the data of different years in the technical soil were found to be mostly negative.

Power-law index and penetration depth of (Nd_xSm_xGd_1−2x)Ba2Cu₃O_7−δ films studied by AC susceptibility

DEFF Research Database (Denmark)

Li, Xiaofen; He, Dong; Grivel, Jean-Claude

2012-01-01

Superconducting (NdxSmxGd1−2x)Ba2Cu3O7−δ films with x=0, 0.1, 0.25, 0.33 were grown by PLD on STO single crystal substrates. The power-law index n and penetration depth λ are studied by AC susceptibility. During cooling, n in films with x ≠ 0 increases much slower compared with the films with x =....... The films with x ≠ 0 also tend to have a longer penetration depth. These properties might be related to the higher possibility for disorder in the mixed (Nd,Sm,Gd)BCO films....

Effect of screening current induced pair breaking on magnetization of superconducting lead nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Yashwant, G.; Prajapat, C.L. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Jayakumar, O.D. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Singh, M.R.; Gupta, S.K. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Tyagi, A.K. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India); Ravikumar, G. [Technical Physics and Prototype Engineering Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400 085 (India)], E-mail: gurazada@barc.gov.in

2008-06-15

Magnetization measurements on lead nanoparticles in the size range 35-45 nm are presented. It is shown that the critical fields in these nanoparticles are enhanced significantly above their bulk values with temperature dependence also distinct from that of bulk. The observed 'type II' like shape of the magnetization curves is explained on the basis of the Ginzburg-Landau phenomenology by invoking the pair breaking effect of the London screening currents, which makes the effective penetration depth an increasing function of the field. The temperature dependence of critical field is found to be consistent with our explanation.

Cs and Cl penetration estimation in mortar from fly ash of MSWI

International Nuclear Information System (INIS)

Yamada, K.; Hosokawa, Y.; Haga, K.; Osako, M.

2015-01-01

By the Fukushima Daiichi accident, radioactive Cs was scattered widely in East Japan. From the viewpoint of radionuclide contaminated wastes management, water soluble Cs in the fly ash of incineration of municipal solid wastes (MSWI-FA) is the most serious problem. When final disposal of MSWI-FA contaminated by radioactive Cs in concrete pit is considered, it is necessary to understand the characteristics of MSWI-FA and Cs penetration behavior into concrete. In this study, the expected solution generated from MSWI-FA is analyzed and immersion test of mortar in this model solution was carried out for several kinds of cement and sand types. Cs showed similar penetration profiles with Cl regardless of cement and sand types. By using fly ash cement, the penetration depth of Cs decreased less than half compared to ordinary Portland cement (OPC). Clay mineral in sand did not affect the penetration of Cs possible because of the competing effect of potassium for Cs adsorption. Assuming a diffusion equation considering non-linear binding, from the measured profiles, diffusion coefficient and parameters of binding were obtained by fitting. Then, the Cs and Cl profiles after 30 years are estimated and penetration depths of Cs and Cl were only 15 mm for fly ash mortar. (authors)

Non destructive measurement for the penetration of contamination inside concrete walls

International Nuclear Information System (INIS)

Rottner, B.

1998-01-01

The scope of this work is to determine the penetration depth of the contamination inside materials like concrete, only using external measurements, avoiding for instance to drill holes in the concrete wall. When dismantling NPP, concrete represents a significant part of the amount of waste. It is then interesting to segregate concrete into different types of waste: ordinary waste, very low level active waste,... This method makes it possible to generate a three dimensional map of the contamination in a concrete wall; this map car be used to adapt the dismantling scenario, and the tools, in order to: - first: decontaminate the wall by scraping the identified contaminated parts, which generates a small quantity of active waste; - second: break down the wall using non nuclear specific methods, generating a large quantity of ordinary waste. The method is based on spectrometric measurements, using two types of information: - the peak to peak ratios for a single radio-nuclide; - the ratio of the peak surface to the baseline enhancement under the peak. Both ratios vary with the penetration depth of the contamination, but rot in the same way. Therefore, the information which is used, will preferably depends on the depth. The correlation of the two ratios to the penetration depth is computed, using two specific calculation codes. One computes the sensitivity of the detector to the direct rays and the other computes the spectrum shape. (author)

Spectrometric kidney depth measurement method

International Nuclear Information System (INIS)

George, P.; Soussaline, F.; Raynaud, C.

1976-01-01

The method proposed uses the single posterior surface measurement of the kidney radioactivity distribution. The ratio C/P of the number of scattered photons to the number of primary photons, which is a function of the tissue depth penetrated, is calculated for a given region. The parameters on which the C/P value depends are determined from studies on phantoms. On the basis of these results the kidney depth was measured on a series of 13 patients and a correlation was established between the value thus calculated and that obtained by the profile method. The reproducibility of the method is satisfactory [fr

Deformation analysis of shallow penetration in clay

Science.gov (United States)

Sagaseta, C.; Whittle, A. J.; Santagata, M.

1997-10-01

A new method of analysis is described for estimating the deformations and strains caused by shallow undrained penetration of piles and caissons in clay. The formulation combines previous analyses for steady, deep penetration, with methods used to compute soil deformations due to near-surface ground loss, and is referred to as the Shallow Strain Path Method (SSPM). Complete analytical solutions for the velocity and strain rates are given for a planar wall, an axisymmetric, closed-ended pile and unplugged, open-ended pile geometries. In these examples, the analyses consider a single source penetrating through the soil at a constant rate, generating a family of penetrometers with rounded tips, referred to as simple wall, pile and tube geometries. Soil deformations and strains are obtained by integrating the velocity and strain rates along the particle paths.The transition from shallow to deep penetration is analysed in detail. Shallow penetration causes heave at the ground surface, while settlements occur only in a thin veneer of material adjacent to the shaft and in a bulb-shaped region around the tip. The size of this region increases with the embedment depth. Deformations inside an open-ended pile/caisson are affected significantly by details of the simple tube wall geometry.

The Radius and Entropy of a Magnetized, Rotating, Fully Convective Star: Analysis with Depth-dependent Mixing Length Theories

Science.gov (United States)

Ireland, Lewis G.; Browning, Matthew K.

2018-04-01

Some low-mass stars appear to have larger radii than predicted by standard 1D structure models; prior work has suggested that inefficient convective heat transport, due to rotation and/or magnetism, may ultimately be responsible. We examine this issue using 1D stellar models constructed using Modules for Experiments in Stellar Astrophysics (MESA). First, we consider standard models that do not explicitly include rotational/magnetic effects, with convective inhibition modeled by decreasing a depth-independent mixing length theory (MLT) parameter α MLT. We provide formulae linking changes in α MLT to changes in the interior specific entropy, and hence to the stellar radius. Next, we modify the MLT formulation in MESA to mimic explicitly the influence of rotation and magnetism, using formulations suggested by Stevenson and MacDonald & Mullan, respectively. We find rapid rotation in these models has a negligible impact on stellar structure, primarily because a star’s adiabat, and hence its radius, is predominantly affected by layers near the surface; convection is rapid and largely uninfluenced by rotation there. Magnetic fields, if they influenced convective transport in the manner described by MacDonald & Mullan, could lead to more noticeable radius inflation. Finally, we show that these non-standard effects on stellar structure can be fabricated using a depth-dependent α MLT: a non-magnetic, non-rotating model can be produced that is virtually indistinguishable from one that explicitly parameterizes rotation and/or magnetism using the two formulations above. We provide formulae linking the radially variable α MLT to these putative MLT reformulations.

Tumor induction and hair follicle damage for different electron penetrations in rat skin

International Nuclear Information System (INIS)

Burns, F.J.; Sinclair, I.P.; Albert, R.E.; Vanderlaan, M.

1976-01-01

The penetration and dose of an electron beam were varied in an attempt to locate the depth in growing-phase rat skin where irradiation was most effective in inducing tumors and morphological damage to the hair follicles. The hair was plucked to initiate the growing phase of the hair cycle, and 12 days later the dorsal skin was irradiated with electrons penetrating 0.5, 1.0, or 2.0 mm at doses from 500 to 4000 rad. Differences in the curves of tumor incidence as a function of dose for different penetrations were best resolved by plotting the results against the 0.4 mm dose, while comparable curves for destruction of the follicles were best resolved by the 0.8 mm dose. Since 0.8 mm corresponded approximately to the depth of the follicles, these results indicated that the target tissues for follicular damage and tumor induction were separated in depth and that the target for tumor induction was probably located in the region above or near the midpoint of the follicles. When the radiation penetrated sufficiently to reach the entire follicle, the number of tumors produced was not significantly greater than the number observed previously in resting-phase skin, and it was inferred that the additional size and greater mitotic activity of the growing-phase follicles at the time of irradiation did not increase the probability of tumor induction

Statistical moments of the angular spectrum of normal waves in a turbulent collisional magnetized plasma

International Nuclear Information System (INIS)

Aistov, A.V.; Gavrilenko, V.G.

1996-01-01

The normal incidence of a small-amplitude electromagnetic wave upon a semi-infinite turbulent collisional plasm with an oblique external magnetic field is considered. Within a small-angle-scattering approximation of the radiative transport theory, a system of differential equations is derived for statistical moments of the angular power spectrum of radiation. The dependences of the spectrum centroid, dispersion, and asymmetry on the depth of penetration are studied numerically. The nonmonotonic behavior of the dispersion is revealed, and an increase in the spectrum width with absorption anisotropy is found within some depth interval. It is shown that, at large depths, the direction of the displacement of the spectrum centroid, does not always coincide with the direction of minimum absorption

Penetration of silver nanoparticles into porcine skin ex vivo using fluorescence lifetime imaging microscopy, Raman microscopy, and surface-enhanced Raman scattering microscopy.

Science.gov (United States)

Zhu, Yongjian; Choe, Chun-Sik; Ahlberg, Sebastian; Meinke, Martina C; Alexiev, Ulrike; Lademann, Juergen; Darvin, Maxim E

2015-05-01

In order to investigate the penetration depth of silver nanoparticles (Ag NPs) inside the skin, porcine ears treated with Ag NPs are measured by two-photon tomography with a fluorescence lifetime imaging microscopy (TPT-FLIM) technique, confocal Raman microscopy (CRM), and surface-enhanced Raman scattering (SERS) microscopy. Ag NPs are coated with poly-N-vinylpyrrolidone and dispersed in pure water solutions. After the application of Ag NPs, porcine ears are stored in the incubator for 24 h at a temperature of 37°C. The TPT-FLIM measurement results show a dramatic decrease of the Ag NPs' signal intensity from the skin surface to a depth of 4 μm. Below 4 μm, the Ag NPs' signal continues to decline, having completely disappeared at 12 to 14 μm depth. CRM shows that the penetration depth of Ag NPs is 11.1 ± 2.1 μm. The penetration depth measured with a highly sensitive SERS microscopy reaches 15.6 ± 8.3 μm. Several results obtained with SERS show that the penetration depth of Ag NPs can exceed the stratum corneum (SC) thickness, which can be explained by both penetration of trace amounts of Ag NPs through the SC barrier and by the measurements inside the hair follicle, which cannot be excluded in the experiment.

Temperature Dependence of Apparent Respiratory Quotients and Oxygen Penetration Depth in Contrasting Lake Sediments

Science.gov (United States)

Sobek, Sebastian; Gudasz, Cristian; Koehler, Birgit; Tranvik, Lars J.; Bastviken, David; Morales-Pineda, María.

2017-11-01

Lake sediments constitute an important compartment in the carbon cycle of lakes, by burying carbon over geological timescales and by production and emission of greenhouse gases. The degradation of organic carbon (OC) in lake sediments is linked to both temperature and oxygen (O2), but the interactive nature of this regulation has not been studied in lake sediments in a quantitative way. We present the first systematic investigation of the effects of temperature on the apparent respiratory quotient (RQ, i.e., the molar ratio between carbon dioxide (CO2) production and O2 consumption) in two contrasting lake sediments. Laboratory incubations of sediment cores of a humic lake and an eutrophic lake across a 1-21°C temperature gradient over 157 days revealed that both CO2 production and O2 consumption were positively, exponentially, and similarly dependent on temperature. The apparent RQ differed significantly between the lake sediments (0.63 ± 0.26 and 0.99 ± 0.28 in the humic and the eutrophic lake, respectively; mean ± SD) and was significantly and positively related to temperature. The O2 penetration depth into the sediment varied by a factor of 2 over the 1-21°C temperature range and was significantly, negatively, and similarly related to temperature in both lake sediments. Accordingly, increasing temperature may influence the overall extent of OC degradation in lake sediments by limiting O2 supply to aerobic microbial respiration to the topmost sediment layer, resulting in a concomitant shift to less effective anaerobic degradation pathways. This suggests that temperature may represent a key controlling factor of the OC burial efficiency in lake sediments.

Extreme value statistics for two-dimensional convective penetration in a pre-main sequence star

Science.gov (United States)

Pratt, J.; Baraffe, I.; Goffrey, T.; Constantino, T.; Viallet, M.; Popov, M. V.; Walder, R.; Folini, D.

2017-08-01

Context. In the interior of stars, a convectively unstable zone typically borders a zone that is stable to convection. Convective motions can penetrate the boundary between these zones, creating a layer characterized by intermittent convective mixing, and gradual erosion of the density and temperature stratification. Aims: We examine a penetration layer formed between a central radiative zone and a large convection zone in the deep interior of a young low-mass star. Using the Multidimensional Stellar Implicit Code (MUSIC) to simulate two-dimensional compressible stellar convection in a spherical geometry over long times, we produce statistics that characterize the extent and impact of convective penetration in this layer. Methods: We apply extreme value theory to the maximal extent of convective penetration at any time. We compare statistical results from simulations which treat non-local convection, throughout a large portion of the stellar radius, with simulations designed to treat local convection in a small region surrounding the penetration layer. For each of these situations, we compare simulations of different resolution, which have different velocity magnitudes. We also compare statistical results between simulations that radiate energy at a constant rate to those that allow energy to radiate from the stellar surface according to the local surface temperature. Results: Based on the frequency and depth of penetrating convective structures, we observe two distinct layers that form between the convection zone and the stable radiative zone. We show that the probability density function of the maximal depth of convective penetration at any time corresponds closely in space with the radial position where internal waves are excited. We find that the maximal penetration depth can be modeled by a Weibull distribution with a small shape parameter. Using these results, and building on established scalings for diffusion enhanced by large-scale convective motions, we

The influence of soil type at Cs-137-spreading in soil depth

International Nuclear Information System (INIS)

Tyrpanova, Kh.; Jordanova, I.

1995-01-01

The distribution of Cs-137 in soil depth up to 15 cm was examined for four types of soil - leached black earth, calcareous black earth, brown forest soil and slightly leached humus-calcareous soil. The behaviour of Cs-137 before and after Chernobyl accident depending on soil type was determined using Cs-134. Accounting for halftime effect of Cs-134 it was possible to distinguish the penetration of the Chernobyl Cs-137 from that of the older one. The same degree of penetration has been achieved: for 30 years for the old Cs-137 and only for a year for the Chernobyl one probably due to its modification. The most expressed tendency to penetrate in depth has been observed at the calcareous black earth (from Kozloduy region, with highest pH value and basis content), the least - at the brown forest soil (from Smolyan region, lowest pH value and basis content). The mineral composition and organic matter content influence the penetration process. The humus matter absorbs Cs-137. Thus it is accessible to the plants, but its penetration is limited to 2.5 cm. 9 refs., 2 tabs. (author)

Ideal magnetohydrodynamic simulations of low beta compact toroid injection into a hot strongly magnetized plasma

Energy Technology Data Exchange (ETDEWEB)

Liu, Wei [Los Alamos National Laboratory; Hsu, Scott [Los Alamos National Laboratory; Li, Hui [Los Alamos National Laboratory

2009-01-01

We present results from three-dimensional ideal magnetohydrodynamic simulations of low {beta} compact toroid (CT) injection into a hot strongly magnetized plasma, with the aim of providing insight into CT fueling of a tokamak with parameters relevant for ITER (International Thermonuclear Experimental Reactor). A regime is identified in terms of CT injection speed and CT-to-background magnetic field ratio that appears promising for precise core fueling. Shock-dominated regimes, which are probably unfavorable for tokamak fueling, are also identified. The CT penetration depth is proportional to the CT injection speed and density. The entire CT evolution can be divided into three stages: (1) initial penetration, (2) compression in the direction of propagation and reconnection, and (3) coming to rest and spreading in the direction perpendicular to injection. Tilting of the CT is not observed due to the fast transit time of the CT across the background plasma.

Orientation dependence of deformation and penetration behavior of tungsten single crystal rods

International Nuclear Information System (INIS)

Bruchey, W.J. Jr.; Horwath, E.J.; Kingman, P.W.

1991-01-01

This paper reports on deformation and flow at a target/penetrator interface that occurs under conditions of high hydrostatic pressure and associated heat generation. To further elucidate the role of material structure in the penetration process, oriented single crystals of tungsten have been launched into steel targets and the residual penetrators recovered and analyzed. Both the penetration depth and the deformation characteristics were strongly influenced by the crystallographic orientation. Deformation modes for the left-angle 100 right-angle rod, which exhibited the best performance, appeared to involve considerable localized slip/cleavage and relatively less plastic working; the residual penetrator was extensively cracked and the eroded penetrator material was extruded in a smooth tube lined with an oriented array of discrete particle exhibiting cleavage fractures. Deformation appeared to be much less localized and to involve more extensive plastic working in the left-angle 011 right-angle rod, which exhibited the poorest penetration, while the left-angle 111 right-angle behaved in an intermediate fashion

Determination of penetration depth at high velocity impact using finite element method and artificial neural network tools

Directory of Open Access Journals (Sweden)

Namık KılıÇ

2015-06-01

Full Text Available Determination of ballistic performance of an armor solution is a complicated task and evolved significantly with the application of finite element methods (FEM in this research field. The traditional armor design studies performed with FEM requires sophisticated procedures and intensive computational effort, therefore simpler and accurate numerical approaches are always worthwhile to decrease armor development time. This study aims to apply a hybrid method using FEM simulation and artificial neural network (ANN analysis to approximate ballistic limit thickness for armor steels. To achieve this objective, a predictive model based on the artificial neural networks is developed to determine ballistic resistance of high hardness armor steels against 7.62 mm armor piercing ammunition. In this methodology, the FEM simulations are used to create training cases for Multilayer Perceptron (MLP three layer networks. In order to validate FE simulation methodology, ballistic shot tests on 20 mm thickness target were performed according to standard Stanag 4569. Afterwards, the successfully trained ANN(s is used to predict the ballistic limit thickness of 500 HB high hardness steel armor. Results show that even with limited number of data, FEM-ANN approach can be used to predict ballistic penetration depth with adequate accuracy.

Influence of massage and occlusion on the ex vivo skin penetration of rigid liposomes and invasomes

DEFF Research Database (Denmark)

Trauer, S.; Richter, H.; Kuntsche, Judith

2014-01-01

Liposomes are frequently described as drug delivery systems for dermal and transdermal applications. Recently, it has been shown that particulate substances penetrate effectively into hair follicles and that the follicular penetration depth can be increased by massaging the skin, which simulates...

Friction force regimes and the conditions for endless penetration of an intruder into a granular medium.

Science.gov (United States)

López-Rodríguez, L A; Pacheco-Vázquez, F

2017-09-01

An intruder penetrating into a granular column experiences a depth-dependent friction force F(z). Different regimes of F(z) have been measured depending on the experimental design: a nearly linear dependence for shallow penetrations, total saturation at large depths, and an exponential increase when the intruder approaches the bottom of the granular bed. We report here an experiment that allows us to measure the different regimes in a single run during the quasistatic descent of a sphere in a light granular medium. From the analysis of the resistance in the saturation zone, it was found that F(z) follows a cube-power-law dependence on the intruder diameter and an exponential increase with the packing fraction of the bed. Moreover, we determine the critical mass m_{c} required to observe infinite penetration and its dependence on the above parameters. Finally, we use our results to estimate the final penetration depth reached by intruders of masses m

About the information depth of backscattered electron imaging

Czech Academy of Sciences Publication Activity Database

Piňos, Jakub; Mikmeková, Šárka; Frank, Luděk

2017-01-01

Roč. 266, č. 3 (2017), s. 335-342 ISSN 0022-2720 Institutional support: RVO:68081731 Keywords : backscattered electrons * information depth * penetration of electrons Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Materials engineering Impact factor: 1.692, year: 2016

Atoms confined in a penetrable potential: effect of the atom position on the electric and magnetic responses

International Nuclear Information System (INIS)

Acosta Coden, Diego S; Gomez, Sergio S; Romero, Rodolfo H

2011-01-01

We report results of the calculation of polarizability and the nuclear magnetic shielding tensors of two-electron atoms confined within an attractive Gaussian potential well. The electric and magnetic responses are obtained within the random phase approximation (RPA) of the polarization propagator. The influence of the depth and range of the potential on the electronic structure is also studied. The dependence of the parallel (along the displacement) and perpendicular components of the polarizability and shielding tensors on the distance of the atom to the centre of the well is calculated and rationalized as a dissociation-type process of the artificial diatomic molecule formed between the Coulomb and the well potentials.

Atoms confined in a penetrable potential: effect of the atom position on the electric and magnetic responses

Energy Technology Data Exchange (ETDEWEB)

Acosta Coden, Diego S; Gomez, Sergio S; Romero, Rodolfo H, E-mail: rhromero@exa.unne.edu.ar [Instituto de Modelado e Innovacion Tecnologica, CONICET and Facultad de Ciencias Exactas y Naturales y Agrimensura, Universidad Nacional del Nordeste, Avenida Libertad 5500 (3400) Corrientes (Argentina)

2011-02-14

We report results of the calculation of polarizability and the nuclear magnetic shielding tensors of two-electron atoms confined within an attractive Gaussian potential well. The electric and magnetic responses are obtained within the random phase approximation (RPA) of the polarization propagator. The influence of the depth and range of the potential on the electronic structure is also studied. The dependence of the parallel (along the displacement) and perpendicular components of the polarizability and shielding tensors on the distance of the atom to the centre of the well is calculated and rationalized as a dissociation-type process of the artificial diatomic molecule formed between the Coulomb and the well potentials.

Ta penetration into template-type porous low-k material during atomic layer deposition of TaN

International Nuclear Information System (INIS)

Furuya, Akira; Ohtsuka, Nobuyuki; Misawa, Kaori; Shimada, Miyoko; Ogawa, Shinichi

2005-01-01

Ta penetration into a planar template-type porous low-k film during atomic layer deposition of TaN has been investigated by evaluating relations between Ta penetration and number of deposition cycles, exposure time of Ta precursor per deposition cycle, substrate temperature, and porosity of the porous low-k. The precursors were pentakisdimethylaminotantalum [PDMAT:Ta(N(CH 3 ) 2 ) 5 ] and NH 3 . The porous low-k was a methylsiloxane (MSX) whose pore size in the maximum distribution and porosity of the porous low-k were 0-1.9 nm and 0%-47%. Depth profile of the Ta penetration was measured by transmission electron microscopy and energy dispersive x-ray spectroscopy. The amount of penetrated and the penetration depth depended on the porosity. It was found that the precursors penetrate into the MSX film dominantly by gas phase diffusion through pores connecting from the surface to the inside. Increased surface area of the MSX film due to the pores results in a depletion of precursor at the wafer edge, and that this depletion causes the penetration characteristics at the edge of wafer differ from those at the center of the wafer. Moreover, the thickness required for the pore sealing by additive liner deposition is discussed

The Beryllium 7 Depth Distribution Study

International Nuclear Information System (INIS)

Jalal Sharib; Zainudin Othman; Dainee Nor Fardzila Ahmad Tugi

2014-01-01

The aim of this paper is to study the evolution of 7Be depth distribution in a soil profile. The soil samples have been collected by using plastic core in bare area in Bangi, Malaysia. Each of the soil core samples has been sectioned into 2 mm increments to a depth of 4 cm and the samples are subsequently oven dried at 45°C and gently disaggregated. The sample is passed through a < 2 mm sieve and packed into plastic pot for 7Be analysis using gamma spectrometry with a 24 hour count time. From the findings, show the 7Be depth penetration from this study decreases exponentially with depth and is confined within the top few centimeters and similar with other works been reported. The further discussion for this findings will be presented in full paper. (author)

Hydrogen atom within spherical boxes with penetrable walls

International Nuclear Information System (INIS)

Ley-Koo, E.; Rubinstein, S.

1979-01-01

We study a model for the hydrogen atom confined within spherical boxes with penetrable walls. The potential consists of the Coulomb potential inside the box and a constant potential outside the box; the Schroedinger equation admits analytical solutions in both regions. The energy eigenvalues and eigenfunctions for the lowest states of the system are determined numerically for boxes of different sizes and penetrabilities. In addition, we also evaluate the hyperfine splitting, nuclear magnetic shielding, polarizability and pressure of the system and investigate the effect of the confinement on these atomic properties

Spin-wave resonance in magnetic films in conditions of skin effect

International Nuclear Information System (INIS)

Nosov, R.N.; Sementsov, D.I.

2002-01-01

The effect of the finite depth of the high-frequency field penetration into the ferromagnetic metal on the spin-wave resonance spectrum perpendicular to the magnetized layer with different types of the spins surface fixation and by availability of attenuation in the spin system is studied. The exact numerical solution of the magnetization motion equation with an account of the skin-layer finite thickness is obtained. The change in the form of the resonance curve on the frequencies close to the frequency of the ferromagnetic resonance is identified in the case of essentially nonuniform high-frequency field distribution by the layer thickness along with widening and decreasing in the amplitude of all resonance peaks [ru

Heat Capacity and Thermal Conductance Measurements of a Superconducting-Normal Mixed State by Detection of Single 3 eV Photons in a Magnetic Penetration Thermometer

Science.gov (United States)

Stevenson, T. R.; Balvin, M. A.; Bandler, S. R.; Denis, K. L.; Lee, S.-J.; Nagler, P. C.; Smith, S. J.

2015-01-01

We report on measurements of the detected signal pulses in a molybdenum-gold Magnetic Penetration Thermometer (MPT) in response to absorption of one or more 3 eV photons. We designed and used this MPT sensor for x-ray microcalorimetry. In this device, the diamagnetic response of a superconducting MoAu bilayer is used to sense temperature changes in response to absorbed photons, and responsivity is enhanced by a Meissner transition in which the magnetic flux penetrating the sensor changes rapidly to minimize free energy in a mixed superconducting normal state. We have previously reported on use of our MPT to study a thermal phonon energy loss to the substrate when absorbing x-rays. We now describe results of extracting heat capacity C and thermal conductance G values from pulse height and decay time of MPT pulses generated by 3 eV photons. The variation in C and G at temperatures near the Meissner transition temperature (set by an internal magnetic bias field) allow us to probe the behavior in superconducting normal mixed state of the condensation energy and the electron cooling power resulting from quasi-particle recombination and phonon emission. The information gained on electron cooling power is also relevant to the operation of other superconducting detectors, such as Microwave Kinetic Inductance Detectors.

Study on Penetration Characteristics of Tungsten Cylindrical Penetrator

Energy Technology Data Exchange (ETDEWEB)

Jo, Jong Hyun; Lee, Young Shin; Kim, Jae Hoon [Chungnam Nat' l Univ., Daejeon (Korea, Republic of); Bae, Yong Woon [Agency for Defense Development, Daejeon (Korea, Republic of)

2013-09-15

The design of missile require extremely small warheads that must be highly efficient and lethal. The penetration characteristics of each penetrator and the total number of penetrators on the warhead are obvious key factors that influence warhead lethality. The design of the penetrator shape and size are directly related to the space and weight of the warhead. The design of the penetrator L/D was directly related to the space and weight of the warhead. L and D are the length and the diameter of the projectile, respectively. The AUTODYN-3a code was used to study the effect of penetrator penetration. The objective of numerical analysis was to determine the penetration characteristics of penetrator produced by hypervelocity impacts under different initial conditions such as initial velocity, obliquity angle and L/D of penetrator. The residual velocity and residual mass were decreased with increasing initial impact velocity under L/D{<=}4.

Dimensional analysis and extended hydrodynamic theory applied to long-rod penetration of ceramics

Directory of Open Access Journals (Sweden)

J.D. Clayton

2016-08-01

Full Text Available Principles of dimensional analysis are applied in a new interpretation of penetration of ceramic targets subjected to hypervelocity impact. The analysis results in a power series representation – in terms of inverse velocity – of normalized depth of penetration that reduces to the hydrodynamic solution at high impact velocities. Specifically considered are test data from four literature sources involving penetration of confined thick ceramic targets by tungsten long rod projectiles. The ceramics are AD-995 alumina, aluminum nitride, silicon carbide, and boron carbide. Test data can be accurately represented by the linear form of the power series, whereby the same value of a single fitting parameter applies remarkably well for all four ceramics. Comparison of the present model with others in the literature (e.g., Tate's theory demonstrates a target resistance stress that depends on impact velocity, linearly in the limiting case. Comparison of the present analysis with recent research involving penetration of thin ceramic tiles at lower typical impact velocities confirms the importance of target properties related to fracture and shear strength at the Hugoniot Elastic Limit (HEL only in the latter. In contrast, in the former (i.e., hypervelocity and thick target experiments, the current analysis demonstrates dominant dependence of penetration depth only by target mass density. Such comparisons suggest transitions from microstructure-controlled to density-controlled penetration resistance with increasing impact velocity and ceramic target thickness.

Estimating residual life of alloy 600 RPV penetrations

International Nuclear Information System (INIS)

Hunt, E.S.; White, G.A.; Pathania, R.; Arey, M.L.; Whitaker, D.E.

1996-01-01

Primary water stress corrosion cracking (PWSCC) of Alloy 600 penetrations PWR in reactor pressure vessel (RPV) heads has become a significant economic concern worldwide. PWSCC of these penetrations has led to extended maintenance outages, expensive inspections and repairs, and in some cases, replacement of the entire vessel head. This paper describes methodology developed to predict the remaining life of Alloy 600 penetrations in reactor vessel heads. Predictions of remaining life are an important input to planning models used by utilities to select a strategy for responding to the PWSCC issue at the lowest life cycle cost with an acceptably low risk of leakage. The remaining life of RPV penetrations is determined using the results of inspections of penetrations and statistical methods to predict future degradation. The analysis takes into account the effects of material properties, welding residual stresses, and operating temperature on PWSCC initiation and growth. The probability of developing cracks of various depths is assessed using Monte Carlo methods which provide for uncertainties in the input assumptions. For plants which have not yet performed inspections, remaining life predictions are based on inspection results from similar plants which have performed inspections with corrections made for known differences in design details, material properties and operating conditions

Capillaric penetration of etchant solution into swift heavy ion-irradiated silicone rubber

International Nuclear Information System (INIS)

Fink, D.; Mueller, M.

2000-01-01

There is growing evidence that etchants penetrate into latent ion tracks in polymers from the very beginning, i.e., even during the so-called 'incubation time' when no visible etchant attack is observed. The model of capillaric penetration of viscous liquids into sponge-like matter agrees with experimental values both in their parametric dependence as in the absolute values. Our experiments are based on LiOH etching of both pristine and swift heavy ion-irradiated silicone rubber foils. About five times more etchant penetrates into irradiated than into pristine silicone rubber. The overall etchant penetration is highest in tracks parallel to the surface normal, and decreases with increasing ion track tilt angle towards the surface normal. The etchant penetration into the tracks proceeds relatively slowly with an effective viscosity comparable to that of heavy machine oil. When swelling starts to predominate, the maximum etchant penetration depth comes to saturation, with the total etchant uptake even decreasing

Quantifying the motion of magnetic particles in excised tissue: Effect of particle properties and applied magnetic field

Energy Technology Data Exchange (ETDEWEB)

Kulkarni, Sandip, E-mail: sandip.d.kulkarni@gmail.com [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); Ramaswamy, Bharath; Horton, Emily; Gangapuram, Sruthi [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); Nacev, Alek [Weinberg Medical Physics, LLC (United States); Depireux, Didier [The Institute for Systems Research, University of Maryland at College Park, MD 20742 (United States); Otomagnetics, LLC (United States); Shimoji, Mika [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); Otomagnetics, LLC (United States); Shapiro, Benjamin [Fischell Department of Bioengineering, University of Maryland at College Park, MD 20742 (United States); The Institute for Systems Research, University of Maryland at College Park, MD 20742 (United States); Otomagnetics, LLC (United States)

2015-11-01

This article presents a method to investigate how magnetic particle characteristics affect their motion inside tissues under the influence of an applied magnetic field. Particles are placed on top of freshly excised tissue samples, a calibrated magnetic field is applied by a magnet underneath each tissue sample, and we image and quantify particle penetration depth by quantitative metrics to assess how particle sizes, their surface coatings, and tissue resistance affect particle motion. Using this method, we tested available fluorescent particles from Chemicell of four sizes (100 nm, 300 nm, 500 nm, and 1 μm diameter) with four different coatings (starch, chitosan, lipid, and PEG/P) and quantified their motion through freshly excised rat liver, kidney, and brain tissues. In broad terms, we found that the applied magnetic field moved chitosan particles most effectively through all three tissue types (as compared to starch, lipid, and PEG/P coated particles). However, the relationship between particle properties and their resulting motion was found to be complex. Hence, it will likely require substantial further study to elucidate the nuances of transport mechanisms and to select and engineer optimal particle properties to enable the most effective transport through various tissue types under applied magnetic fields.

Determination of the neutralization depth of concrete under the aggressive environment influence

Science.gov (United States)

Morzhukhina, Anastasia; Nikitin, Stanislav; Akimova, Elena

2018-03-01

Aggressive environments have a significant impact on destruction of many reinforced concrete structures, such as high-rise constructions or chemical plants. For example, some high-rise constructions are equipped with a swimming pool, so they are exposed to chloride ions in the air. Penetration of aggressive chemical substances into the body of concrete contributes to acceleration of reinforced concrete structure corrosion that in turn leads to load bearing capacity loss and destruction of the building. The article considers and analyzes the main technologies for calculating penetration depth of various aggressive substances into the body of concrete. The calculation of corrosion depth was made for 50-year service life.

Penetration of ASM 981 in canine skin: a comparative study.

Science.gov (United States)

Gutzwiller, Meret E Ricklin; Reist, Martin; Persohn, Elke; Peel, John E; Roosje, Petra J

2006-01-01

ASM 981 has been developed for topical treatment of inflammatory skin diseases. It specifically inhibits the production and release of pro-inflammatory cytokines. We measured the skin penetration of ASM 981 in canine skin and compared penetration in living and frozen skin. To make penetration of ASM 981 visible in dog skin, tritium labelled ASM 981 was applied to a living dog and to defrosted skin of the same dog. Using qualitative autoradiography the radioactive molecules were detected in the lumen of the hair follicles until the infundibulum, around the superficial parts of the hair follicles and into a depth of the dermis of 200 to 500 microm. Activity could not be found in deeper parts of the hair follicles, the dermis or in the sebaceous glands. Penetration of ASM 981 is low in canine skin and is only equally spread in the upper third of the dermis 24 hours after application. Penetration in frozen skin takes even longer than in living canine skin but shows the same distribution.

Influence of the mole penetrator on measurements of heat flow in lunar subsurface layers

Science.gov (United States)

Wawrzaszek, Roman; Drogosz, Michal; Seweryn, Karol; Banaszkiewicz, Marek; Grygorczuk, Jerzy

Measuring the thermal gradient in subsurface layers is a basic method of determination the heat flux from the interior of a planetary body to its surface. In case of the Moon, such measurements complemented with the results of theoretical analysis and modeling can significantly improve our understanding of the thermal and geological evolution of the Moon. In practice, temperature gradient measurements are performed by at least two sensors located at different depths under the surface. These sensors will be attached to a penetrator [1] or to a cable pulled behind the penetrator. In both cases the object that carries the sensors, e.g. penetrator, perturb temperature measurements. In our study we analyze a case of two thermal sensors attached to the ends of 350mm long penetrator made of a composite material. In agreement with the studies of other authors we have found that the penetrator should be placed at the depth of 2-3 meters, where periodic changes of the temperature due to variation of solar flux at the surface are significantly smaller than the error of temperature measurement. The most important result of our analysis is to show how to deconvolve the real gradient of the temperature from the measurements perturbed by the penetrator body. In this way it will be possible to more accurately determine heat flux in the lunar regolith. [1] Grygorczuk J., Seweryn K., Wawrzaszek R., Banaszkiewicz M., Insertion of a Mole Pene-trator -Experimental Results, /39th Lunar and Planetary Science Conference /League City, Texas 2008

Penetration and delivery characteristics of repetitive microjet injection into the skin.

Science.gov (United States)

Römgens, Anne M; Rem-Bronneberg, Debbie; Kassies, Roel; Hijlkema, Markus; Bader, Dan L; Oomens, Cees W J; van Bruggen, Michel P B

2016-07-28

Drugs can be delivered transdermally using jet injectors, which can be an advantageous route compared to oral administration. However, these devices inject large volumes deep into the skin or tissues underneath the skin often causing bruising and pain. This may be prevented by injecting smaller volumes at lower depth in a repetitive way using a microjet injection device. Such a device could be used to apply drugs in a controllable and sustainable manner. However, the efficacy of microjet injection has been rarely examined. In this study, the penetration and delivery capacity was examined of a repetitive microjet injection device. Various experiments were performed on epidermal and full-thickness ex vivo human as well as ex vivo porcine skin samples. Results revealed that microjets with a velocity exceeding 90m/s penetrated an epidermal skin sample with a delivery efficiency of approximately 96%. In full-thickness human skin, the delivery efficiency drastically decreased to a value of approximately 12%. Experiments on full-thickness skin revealed that the microjets penetrated to a depth corresponding to the transition between the papillary and reticular dermis. This depth did not further increase with increasing number of microjets. In vivo studies on rats indicated that intact insulin was absorbed into the systemic circulation. Hence, the microjet injection device was able to deliver medication into the skin, although the drug delivery efficiency should be increased. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of a magnetic field on the excess resistance of SNS sandwiches

International Nuclear Information System (INIS)

Logvenov, G.Y.; Ryazanov, V.V.

1983-01-01

The contribution of superconducting plates to the resistance of Ta--Cu--Ta sandwiches in the presence of a magnetic field of up to 170 Ge is investigated. Near the superconducting transition temperature T/sub c/H, the Ta used was in a mixed (vortical) state. It is shown that the presence of gradients of the order parameter near the Abrikosov vortices appreciably changes the penetration depth of a longitudinal electric field into the superconductor and leads to a corresponding change in the excess resistance of SNS sandwiches

Muon-spin rotation (. mu. SR) study of the temperature dependence of the London penetration depth in copper oxide superconductors

Energy Technology Data Exchange (ETDEWEB)

Keller, H.; Kuendig, W.; Savic, I.M.; Simmler, H.; Staeuble-Puempin, B.; Warden, M.; Zech, D.; Zimmermann, P. (Physik-Inst., Univ. Zurich (Germany)); Kaldis, E.; Karpinski, J.; Rusiecki, S. (Lab. fuer Festkoerperphysik, ETH Zurich (Switzerland)); Brewer, J.H.; Riseman, T.M.; Schneider, J.W. (TRIUMF and Dept. of Physics, Univ. of British Columbia, Vancouver (Canada)); Maeno, Y.; Rossel, C. (IBM Research Div., Zurich Research Lab., Rueschlikon (Switzerland))

1991-12-01

A {mu}SR study of the temperature dependence of the London penetration depth {lambda} in sintered samples of YBa{sub 2}Cu{sub 3}O{sub x} (with various oxygen contents x), YBa{sub 2}Cu{sub 4}O{sub 8} and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} is presented. It is found that the temperature behavior of {lambda} of all these cuprate superconductors is consistent with conventional s-wave pairing. However, there are significant differences concerning the exact temperature dependence of {lambda} in these materials. In YBa{sub 2}Cu{sub 3}O{sub x} with high x, the behavior of {lambda}(T) is well described by the two-fluid model (strong coupling), whereas {lambda}(T) in YBa{sub 2}Cu{sub 3}O{sub x} with low x, YBa{sub 2}Cu{sub 4}O{sub 8} and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} is in better agreement with weak-coupling BCS theory. Possible reasons for the different temperature behavior of {lambda} in these materials are discussed. (orig.).

In vitro investigation of the follicular penetration of porcine ear skin using a nanoparticle-emulsion containing the antiseptic polihexanide

International Nuclear Information System (INIS)

Ulmer, M; Patzelt, A; Lademann, J; Richter, H; Sterry, W; Lange-Asschenfeldt, B; Vergou, T; Kramer, A; Mueller, G

2012-01-01

Earlier investigations regarding the distribution of the bacterial flora on the human skin demonstrate that the hair follicle acts as a bacterial reservoir, providing a quick source for secondary recontamination. These findings highlight the importance of the hair follicle as a target for modern antiseptics. In the present study, we have assessed the follicular penetration of a curcumin-labeled particle-associated antiseptic into porcine skin by laser scanning microscopy. Therefore, the follicular penetration depth of the curcumin-labeled particle-associated antiseptic was compared to the follicular penetration depth of curcumin-labeled particles without antiseptic. The investigation was performed in vitro using porcine skin biopsies. By superposition of the images acquired in the transmission and the fluorescent modus, it was possible to visualize the distribution of the fluorescent dye inside the hair follicles. Quantitative and qualitative results showed that both dispersions penetrated efficiently into the hair follicles. The average penetration depth of the particles with attached antiseptic polihexanide was significantly higher than that of particles without the attached antiseptic. Also, whilst very little sample preparation was needed, laser scanning microscopy was found to be an efficient tool to visualize the skin relief and in particular the hair follicle shaft and localize fluorescent markers within the skin tissue and hair follicles

Projectile Nose Mass Abrasion of High-Speed Penetration into Concrete

Directory of Open Access Journals (Sweden)

Haijun Wu

2012-01-01

Full Text Available Based on the dynamic spherical cavity expansion theory of concrete and the analysis of experimental data, a mass abrasion model of projectile considering the hardness of aggregates, the relative strength of target and projectile, and the initial impact velocity is constructed in this paper. Furthermore, the effect of mass abrasion on the penetration depth of projectile and the influence of hardness of aggregates and strength of projectile on penetration depth and mass loss are also analyzed. The results show that, for the ogive-nose projectile with the CRH of 3 and aspect ratio of 7 penetrating the concrete of 35 MPa, the “rigid-body penetration” model is available when the initial impact velocity is lower than 800 m/s. However, when the initial impact velocity is higher than 800 m/s, the “deforming/eroding body penetration” model should be adopted. Through theoretical analysis and numerical calculation, the results indicate that the initial impact velocity is the most important factor of mass abrasion. The hardness of aggregates and the strength of projectile are also significant factors. But relatively speaking, the sensitivity of strength of projectile to mass abrasion is higher, which indicates that the effect of projectile material on mass abrasion is more dramatic than the hardness of aggregates.

Integrated computation model of lithium-ion battery subject to nail penetration

International Nuclear Information System (INIS)

Liu, Binghe; Yin, Sha; Xu, Jun

2016-01-01

Highlights: • A coupling model to predict battery penetration process is established. • Penetration test is designed and validates the computational model. • Governing factors of the penetration induced short-circuit is discussed. • Critical safety battery design guidance is suggested. - Abstract: The nail penetration of lithium-ion batteries (LIBs) has become a standard battery safety evaluation method to mimic the potential penetration of a foreign object into LIB, which can lead to internal short circuit with catastrophic consequences, such as thermal runaway, fire, and explosion. To provide a safe, time-efficient, and cost-effective method for studying the nail penetration problem, an integrated computational method that considers the mechanical, electrochemical, and thermal behaviors of the jellyroll was developed using a coupled 3D mechanical model, a 1D battery model, and a short circuit model. The integrated model, along with the sub-models, was validated to agree reasonably well with experimental test data. In addition, a comprehensive quantitative analysis of governing factors, e.g., shapes, sizes, and displacements of nails, states of charge, and penetration speeds, was conducted. The proposed computational framework for LIB nail penetration was first introduced. This framework can provide an accurate prediction of the time history profile of battery voltage, temperature, and mechanical behavior. The factors that affected the behavior of the jellyroll under nail penetration were discussed systematically. Results provide a solid foundation for future in-depth studies on LIB nail penetration mechanisms and safety design.

Storage Conditions of Skin Affect Tissue Structure and Subsequent in vitro Percutaneous Penetration

DEFF Research Database (Denmark)

Nielsen, Jesper Bo; Plasencia Gil, Maria Inés; Sørensen, Jens Ahm

2011-01-01

fluorescence microscopy) and in vitro percutaneous penetration of caffeine under four different storage conditions using skin samples from the same donors: fresh skin, skin kept at -20°C for 3 weeks (with or without the use of polyethylene glycol) and at -80°C. Our results show a correlation between increasing...... permeation of caffeine and tissue structural damage caused by the storage conditions, most so after skin storage at -80°C. The presented approach, which combines imaging techniques with studies on percutaneous penetration, enables the link between tissue damage at selected depths and penetration...

Analysis on the resistive force in penetration of a rigid projectile

Directory of Open Access Journals (Sweden)

Xiao-wei Chen

2014-09-01

Full Text Available According to the dimensionless formulae of DOP (depth of penetration of a rigid projectile into different targets, the resistive force which a target exerts on the projectile during the penetration of rigid projectile is theoretically analyzed. In particular, the threshold Vc of impact velocity applicable for the assumption of constant resistive force is formulated through impulse analysis. The various values of Vc corresponding to different pairs of projectile-target are calculated, and the consistency of the relative test data and numerical results is observed.

Effect of Ear and Near-side Single Circular Pit Depth and Bulk Stress on Magnetic Flux Leakage at ferromagnetic Pipeline

International Nuclear Information System (INIS)

Ryu, Kwon Sang; Park, Young Tae; Atherton, D. L.; Clapham, L.

2003-01-01

Magnetic flux leakage (MFL) signals were used for corrosion inspection of buried oil and gas pipeline. 3D finite element analysis was used to examine the effects of far and near-side pit depth and tensile stress on MFL signals. Anisotropci materials were used, and the effects of simulated tensile stress on MFL were investigated. The axial and radial MFL signals depended on far and near-side single pit depth and on the bulk stress, but the circumferential MFL signal did not depend on them. The axial and radial MFL signals increased with increasing pit depth and the bulk stress, but the circumferential MFL signal was scarcely changed

Carbon mineralization and oxygen dynamics in sediments with deep oxygen penetration, Lake Superior

DEFF Research Database (Denmark)

Li, Jiying; Crowe, Sean Andrew; Miklesh, David

2012-01-01

To understand carbon and oxygen dynamics in sediments with deep oxygen penetration, we investigated eight locations (160–318-m depth) throughout Lake Superior. Despite the 2–4 weight percent organic carbon content, oxygen penetrated into the sediment by 3.5 to > 12 cm at all locations. Such deep ...... volume-specific carbon degradation rates were 0.3–1.5 µmol cm−3 d−1; bioturbation coefficient near the sediment surface was 3–8 cm2 yr−1. These results indicate that carbon cycling in large freshwater systems conforms to many of the same trends as in marine systems.......To understand carbon and oxygen dynamics in sediments with deep oxygen penetration, we investigated eight locations (160–318-m depth) throughout Lake Superior. Despite the 2–4 weight percent organic carbon content, oxygen penetrated into the sediment by 3.5 to > 12 cm at all locations. Such deep......, suggesting that temporal variability in deeply oxygenated sediments may be greater than previously acknowledged. The oxygen uptake rates (4.4–7.7 mmol m−2 d−1, average 6.1 mmol m−2 d−1) and carbon mineralization efficiency (∼ 90% of deposited carbon) were similar to those in marine hemipelagic and pelagic...

Spin reorientation transitions of Fe/Ni/Cu(001) studied by using the depth-resolved X-ray magnetic circular dichroism technique

International Nuclear Information System (INIS)

Abe, Hitoshi; Amemiya, Kenta; Matsumura, Daiju; Kitagawa, Soichiro; Watanabe, Hirokazu; Yokoyama, Toshihiko; Ohta, Toshiaki

2006-01-01

The spin reorientation transition (SRT) of Ni/Cu(001) induced by Fe deposition was investigated using the X-ray magnetic circular dichroism (XMCD) method. In-plane magnetized Ni films (= =10ML) also exhibit a transition to in-plane by 1-2ML Fe deposition. A precise magnetic anisotropy phase diagram was obtained using a combination of wedge-shaped Ni samples and stepwise Fe deposition. Magnetic anisotropy energies in the bulk, surface and interface layers of Ni films were separately determined using the depth-resolved XMCD technique, while values in the 1ML and 2ML portions of the Fe films were obtained from the conventional XMCD measurements. The origin of the SRTs is successfully explained with a simple phenomenological layer model using the obtained magnetic anisotropy energies. es

Light penetration structures the deep acoustic scattering layers in the global ocean.

KAUST Repository

Aksnes, Dag L.; Rø stad, Anders; Kaartvedt, Stein; Martinez, Udane; Duarte, Carlos M.; Irigoien, Xabier

2017-01-01

The deep scattering layer (DSL) is a ubiquitous acoustic signature found across all oceans and arguably the dominant feature structuring the pelagic open ocean ecosystem. It is formed by mesopelagic fishes and pelagic invertebrates. The DSL animals are an important food source for marine megafauna and contribute to the biological carbon pump through the active flux of organic carbon transported in their daily vertical migrations. They occupy depths from 200 to 1000 m at daytime and migrate to a varying degree into surface waters at nighttime. Their daytime depth, which determines the migration amplitude, varies across the global ocean in concert with water mass properties, in particular the oxygen regime, but the causal underpinning of these correlations has been unclear. We present evidence that the broad variability in the oceanic DSL daytime depth observed during the Malaspina 2010 Circumnavigation Expedition is governed by variation in light penetration. We find that the DSL depth distribution conforms to a common optical depth layer across the global ocean and that a correlation between dissolved oxygen and light penetration provides a parsimonious explanation for the association of shallow DSL distributions with hypoxic waters. In enhancing understanding of this phenomenon, our results should improve the ability to predict and model the dynamics of one of the largest animal biomass components on earth, with key roles in the oceanic biological carbon pump and food web.

Light penetration structures the deep acoustic scattering layers in the global ocean.

KAUST Repository

Aksnes, Dag L.

2017-05-01

The deep scattering layer (DSL) is a ubiquitous acoustic signature found across all oceans and arguably the dominant feature structuring the pelagic open ocean ecosystem. It is formed by mesopelagic fishes and pelagic invertebrates. The DSL animals are an important food source for marine megafauna and contribute to the biological carbon pump through the active flux of organic carbon transported in their daily vertical migrations. They occupy depths from 200 to 1000 m at daytime and migrate to a varying degree into surface waters at nighttime. Their daytime depth, which determines the migration amplitude, varies across the global ocean in concert with water mass properties, in particular the oxygen regime, but the causal underpinning of these correlations has been unclear. We present evidence that the broad variability in the oceanic DSL daytime depth observed during the Malaspina 2010 Circumnavigation Expedition is governed by variation in light penetration. We find that the DSL depth distribution conforms to a common optical depth layer across the global ocean and that a correlation between dissolved oxygen and light penetration provides a parsimonious explanation for the association of shallow DSL distributions with hypoxic waters. In enhancing understanding of this phenomenon, our results should improve the ability to predict and model the dynamics of one of the largest animal biomass components on earth, with key roles in the oceanic biological carbon pump and food web.

Performance of kevlar fibre-reinforced rubber composite armour against shaped-charge jet penetration

OpenAIRE

Zu,Xu-dong; Huang,Zheng-xiang; Zhai,Wen

2015-01-01

AbstractThe protective capability of the Kevlar fibre-reinforced rubber composite armour (KFRRCA) at different obliquities is studied using depth-of-penetration experiments method against a 56 mm-diameter standard-shaped charge. Efficiency factors are calculated to evaluate the protection capability of the KFRRCA at different obliquities. Meanwhile, an X-ray experiment is used to observe the deformation, fracture, and scatter of the shaped-charge jet as it penetrates the composite armour. Fin...

Effects of inserted depth of wall penetration on basal stability of foundation pits

Science.gov (United States)

Zhou, Aizhao; Shen, Hao; Sun, Jinguo

2017-05-01

Evaluation of basal heave stability is one of important design checks for excavations in soft clays. The commonly used classical calculation method based on limit equilibrium theory and the safety coefficient formula recommended by the current code, do not consider the influence of supporting structure of foundation pit depth heave stability, which results in conservative. Considering the wall stiffness and strength, the effective stress changes in different depth of soil, the frictional resistance between the retaining wall and the passive zone, the vertical shear resistance of the soil behind the wall and other factors. The modified safety factor calculation formula of foundation pit stability is presented, comparison analysis of calculation method combined with examples. The calculation results show that the safety factor of foundation pit stability is improved considering the influence of supporting structure depth, the calculation results are more reasonable.

The Beryllium-7 Depth Study in Different Land Use

International Nuclear Information System (INIS)

Jalal Sharib; Zainudin Othman; Dainee Nor Fardzila Ahmad Tugi; Noor Fadzilah Yusof; Mohd Tarmizi Ishak

2015-01-01

The main objective for this study is to evaluate the evolution of 7 Be depth distribution in soil profile at Tasoh Catchment area, Perlis, Malaysia which area has been different land use. The soil samples for this study have been carried out in Timah surroundings by different agricultural land use. Therefore, three different types of soil samples from different land use have been collected by using metal core and have been sectioned into 2 mm increments to a depth of 4 cm. The samples were brought to Radiochemistry and Environment Group Laboratory (RAS), Bangi for further treatment. The samples subsequently oven dried at 45-60 degree Celsius and gently desegregated. The sample is passed through a < 2 mm sieve and packed into geometry plastic container for 7 Be analysis by using gamma spectrometry with a 24-hour count time. From the findings show that the 7 Be soil samples are penetrated with decreases exponentially with depth and is confined within the top few centimeters at most and similar with other works been reported (Blake et al., 2000 and Walling et al., 2008). , the 7 Be from mixed land use also shows more deeper penetration into the soil depth than from two others land use due to a several factors. Therefore, further and detailed discussion for these findings will be described in full paper. (author)

Deep penetration of light into biotissue

Science.gov (United States)

Bearden, Edward D.; Wilson, James D.; Zharov, Vladimir P.; Lowery, Curtis L.

2001-07-01

The results of a study of deep (several centimeters) light penetration into biological tissue are presented in order to estimate its significance to potentially photosensitive structures and processes including the fetal eyes. In order to accomplish this goal, samples of various tissues (fat, muscle, and uterus) from surgical patients and autopsies were examined with a double integrating sphere arrangement to determine their optical properties. The results were implemented in a Monte Carlo modeling program. Next, optical fiber probes were inserted into the uterus and abdominal wall of patients undergoing laparoscopic procedures. The fibers were couples to a photomultiplier tube with intervening filters allowing measurements of light penetration at various wavelengths. To determine the feasibility of stimulation in utero, a xenon lamp and waveguide were used to transilluminate the abdomen of several labor patients. Light in the range of 630 to 670 nm where the eye sensitivity and penetration depth are well matched, will likely provide the best chance of visual stimulation. Fetal heart rate, fetal movement, and fetal magnetoencephalography (SQUID) and electroencephalography (EEG) were observed in different studies to determine if stimulation has occurred. Since internal organs and the fetus are completely dark adapted, the amount of light required to simulate in our opinion could be on the order of 10(superscript -8 Watts.

Penetration of steady fluid motions into an outer stable layer excited by MHD thermal convection in rotating spherical shells

Science.gov (United States)

Takehiro, Shin-ichi; Sasaki, Youhei

2018-03-01

Penetration of steady magneto-hydrodynamic (MHD) disturbances into an upper strongly stratified stable layer excited by MHD thermal convection in rotating spherical shells is investigated. The theoretical model proposed by Takehiro (2015) is reexamined in the case of steady fluid motion below the bottom boundary. Steady disturbances penetrate into a density stratified MHD fluid existing in the semi-infinite region in the vertical direction. The axis of rotation of the system is tilted with respect to the vertical. The basic magnetic field is uniform and may be tilted with respect to the vertical and the rotation axis. Linear dispersion relation shows that the penetration distance with zero frequency depends on the amplitude of Alfvén wave speed. When Alfvén wave speed is small, viscous diffusion becomes dominant and penetration distance is similar to the horizontal scale of the disturbance at the lower boundary. In contrast, when Alfvén wave speed becomes larger, disturbance can penetrate deeper, and penetration distance becomes proportional to the Alfvén wave speed and inversely proportional to the geometric average of viscous and magnetic diffusion coefficients and to the total horizontal wavenumber. The analytic expression of penetration distance is in good agreement with the extent of penetration of mean zonal flow induced by finite amplitude convection in a rotating spherical shell with an upper stably stratified layer embedded in an axially uniform basic magnetic field. The theory expects that the stable layer suggested in the upper part of the outer core of the earth could be penetrated completely by mean zonal flows excited by thermal/compositional convection developing below the stable layer.

Determining superconducting parameters from analysis of magnetization fluctuation for CaLaBaCu3O7-δ superconductor

International Nuclear Information System (INIS)

Parra Vargas, C.A.; Landinez Tellez, D.A.; Roa-Rojas, J.

2007-01-01

In this work, we report analysis of magnetization fluctuations for the CaLaBaCu 3 O 7- δ superconducting system. We describe a procedure for extracting the penetration depth λ(T) and the coherence length ξ parameters from the magnetization, as a function of the applied magnetic field. This procedure takes the vortex fluctuation into account. The data of the magnetization excess ΔM(T) are analyzed for different values of temperature in the interval from 65 to 73 K. For several magnetic fields we observed a crossover in the magnetization curves at the characteristic temperature value T *=72.2 K. We calculated the data of magnetization excess from the curves of magnetization as a function of the logarithm of the applied field. This procedure was performed for polycrystalline samples of CaLaBaCu 3 O 7- δ by using the proposition of Bulaevskii, Ledvij and Kogan. We notice that the values for these superconducting parameters are in agreement with reports for high-temperature superconductors

Magnetic hyperthermia with hard-magnetic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Kashevsky, Bronislav E., E-mail: bekas@itmo.by [A.V Luikov Heat and Mass Transfer Institute, Belarus Academy of Sciences, P. Brovka str. 15, Minsk 220072 (Belarus); Kashevsky, Sergey B.; Korenkov, Victor S. [A.V Luikov Heat and Mass Transfer Institute, Belarus Academy of Sciences, P. Brovka str. 15, Minsk 220072 (Belarus); Istomin, Yuri P. [N. N. Alexandrov National Cancer Center of Belarus, Lesnoy-2, Minsk 223040 (Belarus); Terpinskaya, Tatyana I.; Ulashchik, Vladimir S. [Institute of Physiology, Belarus Academy of Sciences, Akademicheskaya str. 28, Minsk 220072 (Belarus)

2015-04-15

Recent clinical trials of magnetic hyperthermia have proved, and even hardened, the Ankinson-Brezovich restriction as upon magnetic field conditions applicable to any site of human body. Subject to this restriction, which is harshly violated in numerous laboratory and small animal studies, magnetic hyperthermia can relay on rather moderate heat source, so that optimization of the whole hyperthermia system remains, after all, the basic problem predetermining its clinical perspectives. We present short account of our complex (theoretical, laboratory and small animal) studies to demonstrate that such perspectives should be related with the hyperthermia system based on hard-magnetic (Stoner–Wohlfarth type) nanoparticles and strong low-frequency fields rather than with superparamagnetic (Brownian or Neél) nanoparticles and weak high-frequency fields. This conclusion is backed by an analytical evaluation of the maximum absorption rates possible under the field restriction in the ideal hard-magnetic (Stoner–Wohlarth) and the ideal superparamagnetic (single relaxation time) systems, by theoretical and experimental studies of the dynamic magnetic hysteresis in suspensions of movable hard-magnetic particles, by producing nanoparticles with adjusted coercivity and suspensions of such particles capable of effective energy absorption and intratumoral penetration, and finally, by successful treatment of a mice model tumor under field conditions acceptable for whole human body. - Highlights: • Hard-magnetic nanoparticles are shown superior for hyperthetmia to superparamagnetic. • Optimal system parameters are found from magnetic reversal model in movable particle. • Penetrating suspension of HM particles with aggregation-independent SAR is developed. • For the first time, mice with tumors are healed in AC field acceptable for human body.

Detection and delineation of underground septic tanks in sandy terrain using ground penetrating radar

Science.gov (United States)

Omolaiye, Gabriel Efomeh; Ayolabi, Elijah A.

2010-09-01

A ground penetrating radar (GPR) survey was conducted on the Lekki Peninsula, Lagos State, Nigeria. The primary target of the survey was the delineation of underground septic tanks (ST). A total of four GPR profiles were acquired on the survey site using Ramac X3M GPR equipment with a 250MHz antenna, chosen based on the depth of interest and resolution. An interpretable depth of penetration of 4.5m below the surface was achieved after processing. The method accurately delineated five underground ST. The tops of the ST were easily identified on the radargram based on the strong-amplitude anomalies, the length and the depths to the base of the ST were estimated with 99 and 73 percent confidence respectively. The continuous vertical profiles provide uninterrupted subsurface data along the lines of traverse, while the non-intrusive nature makes it an ideal tool for the accurate mapping and delineation of underground utilities.

Ion-beam-induced topography and compositional changes in depth profiling

International Nuclear Information System (INIS)

Carter, G.; Nobes, M.J.

1992-01-01

When energetic ions penetrate and stop in solids they not only add a new atomic constituent to the matrix but they also create atomic recoils and defects. The fluxes of these entities can give rise to spatial redistribution of atomic components, which may be partly or completely balanced by reordering and relaxation processes. These latter, in turn, may be influenced by fields and gradients induced by the primary relocation processes and by the energy deposited. These will include quasi-thermal, concentration (or chemical potential) and electrostatic gradients and may act to enhance or suppress atomic redistribution. Some, or all, of these processes will operate, depending upon the system under study, when energetic ions are employed to sputter erode a substrate for depth sectioning and, quite generally, can perturb the atomic depth profile that it is intended to evaluate. Theoretical and computational approaches to modelling such processes will be outlined and experimental examples shown which illustrate specific phenomena. In particular the accumulation of implant species and defect generation or redistribution can modify, with increasing ion fluence, the local sputtering mechanism and create further problems in depth profile analysis as a changing surface topography penetrates the solid. Examples of such topographic evolution and its influence on depth profiling analysis will be given and models to explain general and specific behaviour will be outlined. The commonality of models which examine both depth-dependent composition modification and surface topography evolution will be stressed. (author)

Penetration of fast projectiles into resistant media: From macroscopic to subatomic projectiles

Science.gov (United States)

Gaite, José

2017-09-01

The penetration of a fast projectile into a resistant medium is a complex process that is suitable for simple modeling, in which basic physical principles can be profitably employed. This study connects two different domains: the fast motion of macroscopic bodies in resistant media and the interaction of charged subatomic particles with matter at high energies, which furnish the two limit cases of the problem of penetrating projectiles of different sizes. These limit cases actually have overlapping applications; for example, in space physics and technology. The intermediate or mesoscopic domain finds application in atom cluster implantation technology. Here it is shown that the penetration of fast nano-projectiles is ruled by a slightly modified Newton's inertial quadratic force, namely, F ∼v 2 - β, where β vanishes as the inverse of projectile diameter. Factors essential to penetration depth are ratio of projectile to medium density and projectile shape.

Penetration of gold nanoparticles across the stratum corneum layer of thick-Skin.

Science.gov (United States)

Raju, Gayathri; Katiyar, Neeraj; Vadukumpully, Sajini; Shankarappa, Sahadev A

2018-02-01

Transdermal particulate penetration across thick-skin, such as that of palms and sole, is particularly important for drug delivery for disorders such as small fiber neuropathies. Nanoparticle-based drug delivery across skin is believed to have much translational applications, but their penetration especially through thick-skin, is not clear. This study specifically investigates the effectiveness of gold nanoparticles (AuNPs) for thick-skin penetration, especially across the stratum corneum (SC) as a function of particle size. The thick-skinned hind-paw of rat was used to characterize depth and distribution of AuNPs of varying sizes, namely, 22±3, 105±11, and 186±20nm. Epidermal penetration of AuNPs was characterized both, in harvested skin from the hind-paw using a diffusion chamber, as well as in vivo. Harvested skin segments exposed to 22nm AuNPs for only 3h demonstrated higher penetration (pthick-skin allows nanoparticle penetration and acts as a depot for release of AuNPs into circulation long after the initial exposure has ceased. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Magnetic flux penetration and destruction of pion condensates

Energy Technology Data Exchange (ETDEWEB)

Harrington, B J; Shepard, H K [New Hampshire Univ., Durham (USA). Dept. of Physics

1976-08-30

It is shown that an external magnetic field can destroy a pion condensate or lead to a vortex ground state similar to the mixed phase of a type II superconductor. Critical magnetic fields, determined for the ground state phases of the sigma model, are comparable to those which may be present in neutron stars.

Partial liquid-penetration inside a deep trench by film flowing over it

Science.gov (United States)

Nguyen, Phuc-Khanh; Dimakopoulos, Yiannis; Tsamopoulos, John

2014-11-01

Liquid film flow along substrates featuring a deep trench may not wet the trench floor, but create a second gas-liquid interface inside the trench. The liquid penetration inside the trench depends on the location and shape of this inner interface. The penetration increases by decreasing the two three-phase contact lines between the inner interface and the two side-walls or the flow rate and depends on the liquid properties. This partial-penetration is studied by employing the Galerkin / finite element method to solve the two-dimensional steady-state Navier-Stokes equations in a physical domain that is adaptively remeshed. Multiple branches of steady solutions connected via turning points are revealed by pseudo arc-length continuation. Flow hysteresis may occur in a certain range of liquid penetration depth, when the interaction of the two interfaces changes qualitatively. This induces an abrupt jump of penetration distance and deformation amplitude of the outer interface. Work supported by the General Secretariat of Research & Technology of Greece through the program ``Excellence'' (Grant No. 1918) in the framework ``Education and Lifelong Learning'' co-funded by the ESF.

Impact of different solar penetration depths on climate simulations

Directory of Open Access Journals (Sweden)

Xiaobing Zhou

2015-01-01

Full Text Available Three different estimates of shortwave attenuation depth (SWAD of photosynthetically active radiation (PAR derived from remotely sensed ocean colour data have been tested in an ocean general circulation model (OGCM forced with interannual atmospheric forcings. Two estimates (referred to as [Kd(PAR]1-1 and [Kd(PAR]2-1 are calculated from different algorithms based on the diffusive attenuation coefficient at 490 nm and the third one ([Kd(AVE]1-1 is just an average of [Kd(PAR]1-1 and [Kd(PAR]2-1. [Kd(PAR]2-1 is larger than [Kd(PAR]1-1 almost everywhere in the tropical oceans. Our results show that the OGCM with [Kd(PAR]2-1 produces warmer sea surface temperature (SST in the eastern equatorial Pacific and Atlantic and leads to reduce a cold bias in the equatorial cold tongue regions. It has warmer subsurface temperatures in the low latitude, a slower meridional velocity and Pacific equatorial undercurrent (EUC than the model with [Kd(PAR]1-1. These results are similar to previous studies, although we use a different model and different methods. This study has further analysis and firstly reveals that slower EUC and meridional velocity in the model with [Kd(PAR]2-1 are mainly related to the changes of the acceleration due to zonal density gradient. This acceleration driving the EUC eastward in the subsurface becomes smaller in the subsurface along the equatorial Pacific. However, near the sea surface, the zonally averaged accelerations over the different ocean basins are larger in the model with [Kd(PAR]2-1 than that with [Kd(PAR]1-1, which pushes back the poleward meridional transport. The interannual variability in the model with [Kd(PAR]2-1 is generally weaker than that in the experiment with [Kd(PAR]1-1 due to a deeper mixed layer depth. The vertical temperature errors averaged horizontally within the domain of 30°S to 30°N in the experiment with [Kd(AVE]1-1 are almost in the middle of errors of the other two experiments. This indicates that

Tailoring the stress-depth profile in thin films; the case of γ'-Fe4N1-x

International Nuclear Information System (INIS)

Wohlschloegel, M.; Welzel, U.; Mittemeijer, E.J.

2011-01-01

Homogeneous γ'-Fe 4 N 1-x thin films were produced by gas through-nitriding of iron thin films (thickness 800 nm) deposited onto Al 2 O 3 substrates by Molecular Beam Epitaxy. The nitriding parameters were chosen such that the nitrogen concentration within the γ' thin films was considerably lower (x ∼ 0.05) than the stoichiometric value (x = 0). X-ray diffraction stress analysis at constant penetration depths performed after the nitriding step revealed the presence of tensile stress parallel to the surface; the tensile stress was shown to be practically constant over the entire film thickness. For further nitriding treatments, the parameters were adjusted such that nitrogen enrichment occurred near the specimen surface. The depth-dependent nitrogen enrichment could be monitored by evaluating the strain-free lattice parameter of γ' as a function of X-ray penetration depth and relating it to the nitrogen concentration employing a direct relation between lattice parameter and nitrogen concentration. The small compositional variations led to distinct characteristic stress-depth profiles. The stress changes non-monotonously with depth in the film as could be shown by non-destructive X-ray diffraction stress analysis at constant penetration depths. This work demonstrates that by a specific choice of a first and a subsequent nitriding treatment (employing different nitriding potentials and/or different temperatures for both treatments) controlled development of residual stress profiles is possible in thin iron-nitride surface layers.

Spectral Depth Analysis of some Segments of the Bida Basin ...

African Journals Online (AJOL)

ADOWIE PERE

2017-12-16

Dec 16, 2017 ... ABSTRACT: Spectral depth analysis was carried out on ten (10) of the 2009 total magnetic field intensity data sheets covering some segments of the Bida basin, to determine the depth to magnetic basement within the basin. The data was ... groundwater lie concealed beneath the earth surface and the ...

Curie Depth Analysis of the Salton Sea Region, Southern California

Science.gov (United States)

Mickus, Kevin; Hussein, Musa

2016-02-01

Aeromagnetic data were analyzed to determine the bottom of magnetic bodies that might be related to the Curie point depth (CPD) by 2D spectral and 3D inversion methods within the Salton Trough and the surrounding region in southern California. The bottom of the magnetic bodies for 55 × 55 km windows varied in depth between 11 and 23 km in depth using 2D spectral methods. Since the 55 × 55 km square window may include both shallow and deep source, a 3D inversion method was used to provide better resolution of the bottom of the magnetic bodies. The 3D models indicate the depth to the bottom of the magnetic bodies varied between 5 and 23 km. Even though both methods produced similar results, the 3D inversion method produced higher resolution of the CPD depths. The shallowest depths (5-8 km) occur along and west of the Brawley Seismic Zone and the southwestern portion of the Imperial Valley. The source of these shallow CPD values may be related to geothermal systems including hydrothermal circulation and/or partially molten material. Additionally, shallow CPD depths (7-12 km) were found in a northwest-trending zone in the center of the Salton Trough. These depths coincide with previous seismic analyses that indicated a lower crustal low velocity region which is believed to be caused by partially molten material. Lower velocity zones in several regions may be related to fracturing and/or hydrothermal fluids. If the majority of these shallow depths are related to temperature, they are likely associated with the CPD, and the partially molten material extends over a wider zone than previously known. Greater depths within the Salton Trough coincide with the base of basaltic material and/or regions of intense metamorphism intruded by mafic material in the middle/lower crust.

MHD simulation study of compact toroid injection into magnetized plasmas

International Nuclear Information System (INIS)

Suzuki, Yoshio; Kishimoto, Yasuaki

2000-01-01

To understand the fuelling process in a fusion device by a compact toroid (CT) plasmoid injection method, we have carried out MHD numerical simulations where a spheromak-like CT (SCT) is injected into a magnetized target plasma region. So far, we revealed that the penetration depth of the SCT plasma becomes shorter than that estimated from the conducting sphere (CS) model, because in the simulation the Lorentz force of the target magnetic field sequentially decelerates the injected SCT while in the CS model only the magnetic pressure force acts as the deceleration mechanism. In this study, we represent the new theoretical model where the injected SCT is decelerated by both the magnetic pressure force and the magnetic tension force (we call it the non-slipping sphere (NS) model) and investigate in detail the deceleration mechanism of the SCT by comparison with simulation results. As a result, it is found that the decrease of the SCT kinetic energy in the simulation coincides with that in the NS model more than in the CS model. It means that not only the magnetic pressure force but also the magnetic tension force acts as the deceleration mechanism of the SCT. Furthermore, it is revealed that magnetic reconnection between the SCT magnetic field and the target magnetic field plays a role to relax the SCT deceleration. (author)

Magnetic properties of layered superconductors

International Nuclear Information System (INIS)

Mansky, P.A.

1993-01-01

The organic superconductors (BEDT-TTF) 2 Cu(SNC) 2 and (TMTSF) 2 ClO 4 , with T c = 10K and 1.2K, have layered and highly anisotropic crystal structures. This thesis describes AC magnetic susceptibility measurements on these materials which illustrate the consequences of the discrete layered structure for the magnetic properties of the superconducting state. A DC magnetic field applied parallel to the layers of either material causes the rapid suppression of the AC screening response, and this indicates that the pinning restoring force for vortex motion parallel to the layers is anomalously weak in this orientation. This is believed to be due to the small size of the interlayer coherence length relative to the layer spacing. A simple estimate based on the energy and length scales relevant to Josephson coupled layers gives the correct order of magnitude for the pinning force. Pinning for vortices oriented perpendicular to the layers is larger by a factor of 500 for BEDT and 25 for TMTSF. When the DC field is applied at an angle to the layers, the initial suppression of the susceptibility is identical to that for a field parallel to the layers; when the field component normal to the layers exceeds a threshold, a sharp recovery of screening occurs. These observations indicate that the field initially enters the sample only in the direction parallel to the layers. The recovery of screening signals field penetration in the perpendicular direction at higher field strength, and is due to the onset of pinning by in-plane vortex cores. This magnetic open-quotes lock-inclose quotes effect is a qualitatively new behavior and is a direct consequence of weak interlayer coupling. The London penetration depth associated with interlayer currents is found to be on the order of hundreds of microns, comparable to that of a Josephson junction, and two to three orders of magnitude larger than for conventional superconductors

Nonlinear error-field penetration in low density ohmically heated tokamak plasmas

International Nuclear Information System (INIS)

Fitzpatrick, R

2012-01-01

A theory is developed to predict the error-field penetration threshold in low density, ohmically heated, tokamak plasmas. The novel feature of the theory is that the response of the plasma in the vicinity of the resonant surface to the applied error-field is calculated from nonlinear drift-MHD (magnetohydrodynamical) magnetic island theory, rather than linear layer theory. Error-field penetration, and subsequent locked mode formation, is triggered once the destabilizing effect of the resonant harmonic of the error-field overcomes the stabilizing effect of the ion polarization current (caused by the propagation of the error-field-induced island chain in the local ion fluid frame). The predicted scaling of the error-field penetration threshold with engineering parameters is (b r /B T ) crit ∼n e B T -1.8 R 0 -0.25 , where b r is the resonant harmonic of the vacuum radial error-field at the resonant surface, B T the toroidal magnetic field-strength, n e the electron number density at the resonant surface and R 0 the major radius of the plasma. This scaling—in particular, the linear dependence of the threshold with density—is consistent with experimental observations. When the scaling is used to extrapolate from JET to ITER, the predicted ITER error-field penetration threshold is (b r /B T ) crit ∼ 5 × 10 −5 , which just lies within the expected capabilities of the ITER error-field correction system. (paper)

Atomistic simulation of femtosecond laser pulse interactions with a copper film: Effect of dependency of penetration depth and reflectivity on electron temperature

Science.gov (United States)

Amouye Foumani, A.; Niknam, A. R.

2018-01-01

The response of copper films to irradiation with laser pulses of fluences in the range of 100-6000 J/m2 is simulated by using a modified combination of a two-temperature model (TTM) and molecular dynamics (MD). In this model, the dependency of the pulse penetration depth and the reflectivity of the target on electron temperature are taken into account. Also, the temperature-dependent electron-phonon coupling factor, electron thermal conductivity, and electron heat capacity are used in the simulations. Based on this model, the dependence of the integral reflectivity on pulse fluence, the changes in the film thickness, and the evolution of density and electron and lattice temperatures are obtained. Moreover, snapshots that show the melting and disintegration processes are presented. The disintegration starts at a fluence of 4200 J/m2, which corresponds with an absorbed fluence of 616 J/m2. The calculated values of integral reflectivity are in good agreement with the experimental data. The inclusion of such temperature-dependent absorption models in the TTM-MD method would facilitate the comparison of experimental data with simulation results.

Helioseismic Constraints on the Depth Dependence of Large-Scale Solar Convection

Science.gov (United States)

Woodard, Martin F.

2017-08-01

A recent helioseismic statistical waveform analysis of subsurface flow based on a 720-day time series of SOHO/MDI Medium-l spherical-harmonic coefficients has been extended to cover a greater range of subphotospheric depths. The latest analysis provides estimates of flow-dependent oscillation-mode coupling-strength coefficients b(s,t;n,l) over the range l = 30 to 150 of mode degree (angular wavenumber) for solar p-modes in the approximate frequency range 2 to 4 mHz. The range of penetration depths of this mode set covers most of the solar convection zone. The most recent analysis measures spherical harmonic (s,t) components of the flow velocity for odd s in the angular wavenumber range 1 to 19 for t not much smaller than s at a given s. The odd-s b(s,t;n,l) coefficients are interpreted as averages over depth of the depth-dependent amplitude of one spherical-harmonic (s,t) component of the toroidal part of the flow velocity field. The depth-dependent weighting function defining the average velocity is the fractional kinetic energy density in radius of modes of the (n,l) multiplet. The b coefficients have been converted to estimates of root velocity power as a function of l0 = nu0*l/nu(n,l), which is a measure of mode penetration depth. (nu(n,l) is mode frequency and nu0 is a reference frequency equal to 3 mHz.) A comparison of the observational results with simple convection models will be presented.

A novel method for imitating nacre by utilizing magnetic graphene oxide and its magnetic field alignment in polymer nanocomposites

Science.gov (United States)

Liu, Zhenxiang; Jiao, Weicheng; Yan, Meiling; Li, Jun; Ding, Guomin; Wang, Rongguo

2018-02-01

The way gas molecules penetrate the resin matrix composites are generally divided into diffusion penetration and destruction penetration. Through theoretical analysis, the larger the nanoscale layers, the smaller the penetration effect in the directional nanosheets reinforced resin matrix composites. To control destruction penetration, the cracks should be reduced by toughening resin matrix composites. In order to solve these two kinds of leakage, the magnetic graphene oxide is connected to mimic nacre while L- glutamic acid is used as binder and the directional solidification is also utilized. Compared with pure resin, only 0.13 wt% monolithic magnetic graphene oxide and its interbed reinforced composites can reduce the leakage of He by 36.4% and 52.0% respectively, and the toughness of composites is validated to increase 4.0% and 20.3% respectively. This toughening mechanism is similar to that of nacre.

Chloride Penetration through Cracks in High-Performance Concrete and Surface Treatment System for Crack Healing

Directory of Open Access Journals (Sweden)

In-Seok Yoon

2012-01-01

Full Text Available For enhancing the service life of concrete structures, it is very important to minimize crack at surface. Even if these cracks are very small, the problem is to which extend these cracks may jeopardize the durability of these decks. It was proposed that crack depth corresponding with critical crack width from the surface is a crucial factor in view of durability design of concrete structures. It was necessary to deal with chloride penetration through microcracks characterized with the mixing features of concrete. This study is devoted to examine the effect of high strength concrete and reinforcement of steel fiber on chloride penetration through cracks. High strength concrete is regarded as an excellent barrier to resist chloride penetration. However, durability performance of cracked high strength concrete was reduced seriously up to that of ordinary cracked concrete. Steel fiber reinforcement is effective to reduce chloride penetration through cracks because steel fiber reinforcement can lead to reduce crack depth significantly. Meanwhile, surface treatment systems are put on the surface of the concrete in order to seal the concrete. The key-issue is to which extend a sealing is able to ensure that chloride-induced corrosion can be prevented. As a result, penetrant cannot cure cracks, however, coating and combined treatment can prevent chloride from flowing in concrete with maximum crack width of 0.06 mm and 0.08 mm, respectively.

Ground Penetrating Radar, Magnetic and Compositional Analysis of Sediment Cores and Surface Samples: The Relationships Between Lacustrine Sediments and Holocene Lake- Level and Climate Change at Deming Lake, Minnesota, USA

Science.gov (United States)

Murray, R.; Lascu, I.; Plank, C.

2007-12-01

Deming Lake is a small (Deming. Cores were sampled continuously at a 1-2 cm resolution and sediment composition (in terms of percent organic matter, carbonate material, and minerogenic residue) was determined via loss on ignition (LOI). Isothermal remanent magnetization (IRM) and anhysteretic remanent magnetization (ARM) were used as proxies of magnetic mineral concentration and grain size. Four lithostratigraphic units were identified and correlated between cores based on these analyses. Changes in GPR facies corroborate the correlation between the two shallow cores. In order to inform our interpretation of down-core variations in magnetic properties and LOI values in terms of variations in lake depth, a suite of over 70 modern sediment samples were collected from the basin and analyzed. LOI compositional variability across the basin was high, with no clear trends related to depth or distance from shore. A sharp decrease in minerogenic content was observed at depths consistent with a predicted wave-base of 0.5 m, but aside from this trend it appears the steep slopes of much of the basin promote gravity driven slumping and mixing of sediments at depth. In the profundal sediments IRM values are routinely 5% higher than in the slope and littoral environments, while ARM/IRM ratios indicate an increase in magnetic grain size with water depth. We infer that an increase in coarse organic material in the shallow-water cores of Deming records a period of aridity (associated with a decrease lake-level less than 2m based on GPR profiles) and/or increased water clarity during the regionally expansive mid-Holocene dry period. We do not see clear evidence of late-Holocene lake level change of a significant magnitude (i.e. >1m). While remanence measurements (especially IRM) often correlate with the LOI residue, interference in the IRM resulting from the dissolution of magnetic minerals casts uncertainty into the reliability of our magnetic measurements as a signal of climate

In-vivo dynamic characterization of microneedle skin penetration using optical coherence tomography

Science.gov (United States)

Enfield, Joey; O'Connell, Marie-Louise; Lawlor, Kate; Jonathan, Enock; O'Mahony, Conor; Leahy, Martin

2010-07-01

The use of microneedles as a method of circumventing the barrier properties of the stratum corneum is receiving much attention. Although skin disruption technologies and subsequent transdermal diffusion rates are being extensively studied, no accurate data on depth and closure kinetics of microneedle-induced skin pores are available, primarily due to the cumbersome techniques currently required for skin analysis. We report on the first use of optical coherence tomography technology to image microneedle penetration in real time and in vivo. We show that optical coherence tomography (OCT) can be used to painlessly measure stratum corneum and epidermis thickness, as well as microneedle penetration depth after microneedle insertion. Since OCT is a real-time, in-vivo, nondestructive technique, we also analyze skin healing characteristics and present quantitative data on micropore closure rate. Two locations (the volar forearm and dorsal aspect of the fingertip) have been assessed as suitable candidates for microneedle administration. The results illustrate the applicability of OCT analysis as a tool for microneedle-related skin characterization.

Time-domain single-source integral equations for analyzing scattering from homogeneous penetrable objects

KAUST Repository

Valdé s, Felipe; Andriulli, Francesco P.; Bagci, Hakan; Michielssen, Eric

2013-01-01

Single-source time-domain electric-and magnetic-field integral equations for analyzing scattering from homogeneous penetrable objects are presented. Their temporal discretization is effected by using shifted piecewise polynomial temporal basis

Penetration of Streptococcus sobrinus and Streptococcus sanguinis into dental enamel.

Science.gov (United States)

Kneist, Susanne; Nietzsche, Sandor; Küpper, Harald; Raser, Gerhard; Willershausen, Brita; Callaway, Angelika

2015-10-01

The aim of this pilot study was to assess the difference in virulence of acidogenic and aciduric oral streptococci in an in vitro caries model using their penetration depths into dental enamel. 30 caries-free extracted molars from 11- to 16-year-olds were cleaned ultrasonically for 1 min with de-ionized water and, after air-drying, embedded in epoxy resin. After 8-h of setting at room temperature, the specimens were ground on the buccal side with SiC-paper 1200 (particle size 13-16 μm). Enamel was removed in circular areas sized 3 mm in diameter; the mean depth of removed enamel was 230 ± 60 μm. 15 specimens each were incubated anaerobically under standardized conditions with 24 h-cultures of Streptococcus sanguinis 9S or Streptococcus sobrinus OMZ 176 in Balmelli broth at 37 ± 2 °C; the pH-values of the broths were measured at the beginning and end of each incubation cycle. After 2, 4, 6, 8, and 10 weeks 3 teeth each were fixed in 2.5% glutaraldehyde in cacodylate buffer for 24 h, washed 3× and dehydrated 30-60min by sequential washes through a series of 30-100% graded ethanol. The teeth were cut in half longitudinally; afterward, two slits were made to obtain fracture surfaces in the infected area. After critical-point-drying the fragments were gold-sputtered and viewed in a scanning electron microscope at magnifications of ×20-20,000. After 10 weeks of incubation, penetration of S. sanguinis of 11.13 ± 24.04 μm below the break edges into the enamel was observed. The invasion of S. sobrinus reached depths of 87.53 ± 76.34 μm. The difference was statistically significant (paired t test: p = 0.033). The experimental penetration depths emphasize the importance of S. sanguinis versus S. sobrinus in the context of the extended ecological plaque hypothesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Monitoring of active layer dynamics at a permafrost site on Svalbard using multi-channel ground-penetrating radar

Directory of Open Access Journals (Sweden)

S. Westermann

2010-11-01

Full Text Available Multi-channel ground-penetrating radar is used to investigate the late-summer evolution of the thaw depth and the average soil water content of the thawed active layer at a high-arctic continuous permafrost site on Svalbard, Norway. Between mid of August and mid of September 2008, five surveys have been conducted in gravelly soil over transect lengths of 130 and 175 m each. The maximum thaw depths range from 1.6 m to 2.0 m, so that they are among the deepest thaw depths recorded in sediments on Svalbard so far. The thaw depths increase by approximately 0.2 m between mid of August and beginning of September and subsequently remain constant until mid of September. The thaw rates are approximately constant over the entire length of the transects within the measurement accuracy of about 5 to 10 cm. The average volumetric soil water content of the thawed soil varies between 0.18 and 0.27 along the investigated transects. While the measurements do not show significant changes in soil water content over the first four weeks of the study, strong precipitation causes an increase in average soil water content of up to 0.04 during the last week. These values are in good agreement with evapotranspiration and precipitation rates measured in the vicinity of the the study site. While we cannot provide conclusive reasons for the detected spatial variability of the thaw depth at the study site, our measurements show that thaw depth and average soil water content are not directly correlated.

The study demonstrates the potential of multi-channel ground-penetrating radar for mapping thaw depth in permafrost areas. The novel non-invasive technique is particularly useful when the thaw depth exceeds 1.5 m, so that it is hardly accessible by manual probing. In addition, multi-channel ground-penetrating radar holds potential for mapping the latent heat content of the active layer and for estimating weekly to monthly averages of the ground heat flux during the

Characterization of compact-toroid injection during formation, translation, and field penetration

Science.gov (United States)

Matsumoto, T.; Roche, T.; Allfrey, I.; Sekiguchi, J.; Asai, T.; Gota, H.; Cordero, M.; Garate, E.; Kinley, J.; Valentine, T.; Waggoner, W.; Binderbauer, M.; Tajima, T.

2016-11-01

We have developed a compact toroid (CT) injector system for particle refueling of the advanced beam-driven C-2U field-reversed configuration (FRC) plasma. The CT injector is a magnetized coaxial plasma gun (MCPG), and the produced CT must cross the perpendicular magnetic field surrounding the FRC for the refueling of C-2U. To simulate this environment, an experimental test stand has been constructed. A transverse magnetic field of ˜1 kG is established, which is comparable to the C-2U axial magnetic field in the confinement section, and CTs are fired across it. On the test stand we have been characterizing and studying CT formation, ejection/translation from the MCPG, and penetration into transverse magnetic fields.

Characterization of compact-toroid injection during formation, translation, and field penetration

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, T., E-mail: cstd14003@g.nihon-u.ac.jp; Sekiguchi, J.; Asai, T. [Nihon University, Chiyoda-ku, Tokyo 101-8308 (Japan); Roche, T.; Allfrey, I.; Gota, H.; Cordero, M.; Garate, E.; Kinley, J.; Valentine, T.; Waggoner, W.; Binderbauer, M. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); Tajima, T. [Tri Alpha Energy, Inc., P.O. Box 7010, Rancho Santa Margarita, California 92688 (United States); Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)

2016-11-15

We have developed a compact toroid (CT) injector system for particle refueling of the advanced beam-driven C-2U field-reversed configuration (FRC) plasma. The CT injector is a magnetized coaxial plasma gun (MCPG), and the produced CT must cross the perpendicular magnetic field surrounding the FRC for the refueling of C-2U. To simulate this environment, an experimental test stand has been constructed. A transverse magnetic field of ∼1 kG is established, which is comparable to the C-2U axial magnetic field in the confinement section, and CTs are fired across it. On the test stand we have been characterizing and studying CT formation, ejection/translation from the MCPG, and penetration into transverse magnetic fields.

Performance evaluation of lunar penetrating radar onboard the rover of CE-3 probe based on results from ground experiments

Science.gov (United States)

Zhang, Hong-Bo; Zheng, Lei; Su, Yan; Fang, Guang-You; Zhou, Bin; Feng, Jian-Qing; Xing, Shu-Guo; Dai, Shun; Li, Jun-Duo; Ji, Yi-Cai; Gao, Yun-Ze; Xiao, Yuan; Li, Chun-Lai

2014-12-01

Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness of the lunar regolith, which are key elements for studying the evolutional history of lunar crust. Because penetration depth and resolution of LPR are related to the scientific objectives of this mission, a series of ground-based experiments using LPR was carried out, and results of the experimental data were obtained in a glacial area located in the northwest region of China. The results show that the penetration depth of the first channel antenna used for LPR is over 79 m with a resolution of 2.8 m, and that for the second channel antenna is over 50.8 m with a resolution of 17.1 cm.

Theory and MHD simulation of fuelling process by Compact Toroid (CT) injection

International Nuclear Information System (INIS)

Suzuki, Y.; Hayashi, T.; Kishimoto, Y.

2001-01-01

The fuelling process by a spheromak-like compact toroid (SCT) injection is investigated by using MHD numerical simulations, where the SCT is injected into a magnetized target plasma region corresponding to a fusion device. In our previous study, the theoretical model to determine the penetration depth of the SCT into the target region has been proposed based on the simulation results, in which the SCT is decelerated not only by the magnetic pressure force but also by the magnetic tension force. However, since both ends of the target magnetic field are fixed on the boundary wall in the simulation, the deceleration caused by the magnetic tension force would be overestimated. In this study, the dependence of the boundary condition of the target magnetic field on the SCT penetration process is examined. From these results, the theoretical model we have proposed is improved to include the effect that the wave length of the target magnetic field bent by the SCT penetration expands with the Alfven velocity. In addition, by carrying out the simulation with the torus domain, it is confirmed that the theoretical model is applicable to estimate the penetration depth of the SCT under such conditions. Furthermore, the dependence of the injection position (the side injection and the top/bottom injection) on the penetration process is examined. (author)

Three-dimensional in-situ subsurface density estimations and the seismic skin depth

CSIR Research Space (South Africa)

Fourie, CJS

2008-01-01

Full Text Available All electromagnetic geophysical methods, but the frequency domain methods in particular, depend on the skindepth as a guide to the depth of investigation or penetration from the surface. By definition the skindepth is the distance where the initial...

USING GROUND PENETRATING RADAR TO DETERMINE THE TUNNEL LOCATION BURIED UNDER THE GLACIER

Directory of Open Access Journals (Sweden)

Deryuga Andrey Mikhaylovich

2013-09-01

Full Text Available The works were carried out with the help of ground penetrating radar “Grot-10”. Doublet broadband antennas with the central frequency of 100 MHz were used. Georadar measures the speed of EM waves v in ice-saturated soil and then the value ε′ is calculated. The radargrams received as a result of georadar survey, which represents stacked data (the two-way time is indicated on vertical scale, were transformed into depth sections, which reflect the space structure located below ground. The distance between the bottom landing and buried mountain road near the north tunnel portal is 78,5 m (profile # 1, and the distance from the upper landing is 84,5 m (profile no. 2. Later, in the April 2003 during the hole boring with the diameter 1,2 m the vertical distance between the upper landing, where ground penetrating works were carried out, and the carpet road of the tunnel was calculated. This distance appeared to be 83 m, that means, the discrepancy between boring and georadar data (84,5 m was only 1,5 m. Thus, the results of ground penetrating investigations helped the workers of glacier to make the correct conclusion on time about the location and burial depth of the tunnel.

Localization of dexamethasone within dendritic core-multishell (CMS) nanoparticles and skin penetration properties studied by multi-frequency electron paramagnetic resonance (EPR) spectroscopy.

Science.gov (United States)

Saeidpour, S; Lohan, S B; Anske, M; Unbehauen, M; Fleige, E; Haag, R; Meinke, M C; Bittl, R; Teutloff, C

2017-07-01

The skin and especially the stratum corneum (SC) act as a barrier and protect epidermal cells and thus the whole body against xenobiotica of the external environment. Topical skin treatment requires an efficient drug delivery system (DDS). Polymer-based nanocarriers represent novel transport vehicles for dermal application of drugs. In this study dendritic core-multishell (CMS) nanoparticles were investigated as promising candidates. CMS nanoparticles were loaded with a drug (analogue) and were applied to penetration studies of skin. We determined by dual-frequency electron paramagnetic resonance (EPR) how dexamethasone (Dx) labelled with 3-carboxy-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (PCA) is associated with the CMS. The micro-environment of the drug loaded to CMS nanoparticles was investigated by pulsed high-field EPR at cryogenic temperature, making use of the fact that magnetic parameters (g-, A-matrices, and spin-lattice relaxation time) represent specific probes for the micro-environment. Additionally, the rotational correlation time of spin-labelled Dx was probed by continuous wave EPR at ambient temperature, which provides independent information on the drug environment. Furthermore, the penetration depth of Dx into the stratum corneum of porcine skin after different topical applications was investigated. The location of Dx in the CMS nanoparticles is revealed and the function of CMS as penetration enhancers for topical application is shown. Copyright © 2016 Elsevier B.V. All rights reserved.

Penetration of relativistic heavy ions through matter

International Nuclear Information System (INIS)

Scheidenberger, C.; Geissel, H.

1997-07-01

New heavy-ion accelerators covering the relativistic and ultra-relativistic energy regime allow to study atomic collisions with bare and few-electron projectiles. High-resolution magnetic spectrometers are used for precise stopping-power and energy-loss straggling measurements. Refined theories beyond the Born approximation have been developed and are confirmed by experiments. This paper summarizes the large progress in the understanding of relativistic heavy-ion penetration through matter, which has been achieved in the last few years. (orig.)

Fundamental studies of superconductors using scanning magnetic imaging

Energy Technology Data Exchange (ETDEWEB)

Kirtley, J R [Center for Probing the Nanoscale, Stanford University, Stanford, CA (United States)

2010-12-01

In this review I discuss the application of scanning magnetic imaging to fundamental studies of superconductors, concentrating on three scanning magnetic microscopies-scanning SQUID microscopy (SSM), scanning Hall bar microscopy (SHM) and magnetic force microscopy (MFM). I briefly discuss the history, sensitivity, spatial resolution, invasiveness and potential future developments of each technique. I then discuss a selection of applications of these microscopies. I start with static imaging of magnetic flux: an SSM study provides deeper understanding of vortex trapping in narrow strips, which are used to reduce noise in superconducting circuitry. Studies of vortex trapping in wire lattices, clusters and arrays of rings and nanoholes show fascinating ordering effects. The cuprate high-T{sub c} superconductors are shown to have predominantly d-wave pairing symmetry by magnetic imaging of the half-integer flux quantum effect. Arrays of superconducting rings act as a physical analog for the Ising spin model, with the half-integer flux quantum effect helping to eliminate one source of disorder in antiferromagnetic arrangements of the ring moments. Tests of the interlayer tunneling model show that the condensation energy available from this mechanism cannot account for the high critical temperatures observed in the cuprates. The strong divergence in the magnetic fields of Pearl vortices allows them to be imaged using SSM, even for penetration depths of a millimeter. Unusual vortex arrangements occur in samples comparable in size to the coherence length. Spontaneous magnetization is not observed in Sr{sub 2}RuO{sub 4}, which is believed to have p{sub x} {+-} ip{sub y} pairing symmetry, although effects hundreds of times bigger than the sensitivity limits had been predicted. However, unusual flux trapping is observed in this superconductor. Finally, unusual flux arrangements are also observed in magnetic superconductors. I then turn to vortex dynamics: imaging of vortices

Fundamental studies of superconductors using scanning magnetic imaging

Science.gov (United States)

Kirtley, J. R.

2010-12-01

In this review I discuss the application of scanning magnetic imaging to fundamental studies of superconductors, concentrating on three scanning magnetic microscopies—scanning SQUID microscopy (SSM), scanning Hall bar microscopy (SHM) and magnetic force microscopy (MFM). I briefly discuss the history, sensitivity, spatial resolution, invasiveness and potential future developments of each technique. I then discuss a selection of applications of these microscopies. I start with static imaging of magnetic flux: an SSM study provides deeper understanding of vortex trapping in narrow strips, which are used to reduce noise in superconducting circuitry. Studies of vortex trapping in wire lattices, clusters and arrays of rings and nanoholes show fascinating ordering effects. The cuprate high-Tc superconductors are shown to have predominantly d-wave pairing symmetry by magnetic imaging of the half-integer flux quantum effect. Arrays of superconducting rings act as a physical analog for the Ising spin model, with the half-integer flux quantum effect helping to eliminate one source of disorder in antiferromagnetic arrangements of the ring moments. Tests of the interlayer tunneling model show that the condensation energy available from this mechanism cannot account for the high critical temperatures observed in the cuprates. The strong divergence in the magnetic fields of Pearl vortices allows them to be imaged using SSM, even for penetration depths of a millimeter. Unusual vortex arrangements occur in samples comparable in size to the coherence length. Spontaneous magnetization is not observed in Sr2RuO4, which is believed to have px ± ipy pairing symmetry, although effects hundreds of times bigger than the sensitivity limits had been predicted. However, unusual flux trapping is observed in this superconductor. Finally, unusual flux arrangements are also observed in magnetic superconductors. I then turn to vortex dynamics: imaging of vortices in rings of highly underdoped

Energy-depth relation of electrons in bulk targets by Monte-Carlo calculations

International Nuclear Information System (INIS)

Gaber, M.; Fitting, H.J.

1984-01-01

Monte-Carlo calculations are used to calculate the energy of penetrating electrons as a function of the depth in thick targets of Ti, Fe, Cu, As, In, and Au. It is shown that the mean energy ratio anti E(z)/E 0 decays exponentially with depth z and depends on the backscattering coefficient eta/sub B/ of the bulk material and the maximum range R(E 0 ) of the primary electrons with initial energy E 0 . Thereby a normalized plot anti E/E 0 as a function of the reduced depth z/R becomes possible. (author)

The Effect of Finite Thickness Extent on Estimating Depth to Basement from Aeromagnetic Data

Science.gov (United States)

Blakely, R. J.; Salem, A.; Green, C. M.; Fairhead, D.; Ravat, D.

2014-12-01

Depth to basement estimation methods using various components of the spectral content of magnetic anomalies are in common use by geophysicists. Examples of these are the Tilt-Depth and SPI methods. These methods use simple models having the base of the magnetic body at infinity. Recent publications have shown that this 'infinite depth' assumption causes underestimation of the depth to the top of sources, especially in areas where the bottom of the magnetic layer is shallow, as would occur in high heat-flow regions. This error has been demonstrated in both model studies and using real data with seismic or well control. To overcome the limitation of infinite depth this contribution presents the mathematics for a finite depth contact body in the Tilt depth and SPI methods and applies it to the central Red Sea where the Curie isotherm and Moho are shallow. The difference in the depth estimation between the infinite and finite contacts is such a case is significant and can exceed 200%.

Performance evaluation of lunar penetrating radar onboard the rover of CE-3 probe based on results from ground experiments

International Nuclear Information System (INIS)

Zhang Hong-Bo; Zheng Lei; Su Yan; Feng Jian-Qing; Xing Shu-Guo; Dai Shun; Li Jun-Duo; Xiao Yuan; Li Chun-Lai; Fang Guang-You; Zhou Bin; Ji Yi-Cai; Gao Yun-Ze

2014-01-01

Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness of the lunar regolith, which are key elements for studying the evolutional history of lunar crust. Because penetration depth and resolution of LPR are related to the scientific objectives of this mission, a series of ground-based experiments using LPR was carried out, and results of the experimental data were obtained in a glacial area located in the northwest region of China. The results show that the penetration depth of the first channel antenna used for LPR is over 79 m with a resolution of 2.8 m, and that for the second channel antenna is over 50.8 m with a resolution of 17.1 cm

A comparative study on the transdermal penetration effect of gaseous and aqueous plasma reactive species

Science.gov (United States)

Liu, Xin; Gan, Lu; Ma, Mingyu; Zhang, Song; Liu, Jingjing; Chen, Hongxiang; Liu, Dawei; Lu, Xinpei

2018-02-01

To improve the depth of plasma active species in the skin, it is very important to develop skin disease treatment using plasma. In this article, an air plasma source was used to work directly with the skin of a mouse. A tortuous pathway, hair follicles, electroporation and a microneedle do not aid the transdermal delivery of gaseous plasma active species, therefore these gaseous plasma active species cannot penetrate mouse skin with a thickness of ~0.75 mm. The plasma activated water (PAW) produced by the air plasma source was used to study the transdermal penetration of the aqueous plasma activated species. This aqueous plasma activated species can penetrate the skin through hair follicles, intercellular and transcellular routes. The pH of the PAW did not affect the penetration efficiency of the aqueous plasma active species.

High-resolution mapping, modeling, and evolution of subsurface geomorphology using ground-penetrating radar techniques

Digital Repository Service at National Institute of Oceanography (India)

Loveson, V.J.; Gujar, A.R.

subsurface. It has been useful to decipher shallow geomorphic structures having various options to use different antennas for different depth penetration (0-30 m) with higher resolution.   7.2 Principles of GPR  Ground Penetrating Radar (GPR) was invented... about 90m. Flat and plain land is being used, at present, for agriculture (paddy cultivation) practice. Sand dunes are low lying and highly reworked due to social forestry plantation (acacia) activities. 13    7.8.6 Paleo­Lagoon  GPR data shows two...

Detour factors in water and plastic phantoms and their use for range and depth scaling in electron-beam dosimetry

International Nuclear Information System (INIS)

Fernandez-Varea, J.M.; Andreo, P.; Tabata, T.

1996-01-01

Average penetration depths and detour factors of 1-50 MeV electrons in water and plastic materials have been computed by means of analytical calculation, within the continuous-slowing-down approximation and including multiple scattering, and using the Monte Carlo codes ITS and PENELOPE. Results are compared to detour factors from alternative definitions previously proposed in the literature. Different procedures used in low-energy electron-beam dosimetry to convert ranges and depths measured in plastic phantoms into water-equivalent ranges and depths are analysed. A new simple and accurate scaling method, based on Monte Carlo-derived ratios of average electron penetration depths and thus incorporating the effect of multiple scattering, is presented. Data are given for most plastics used in electron-beam dosimetry together with a fit which extends the method to any other low-Z plastic material. A study of scaled depth - dose curves and mean energies as a function of depth for some plastics of common usage shows that the method improves the consistency and results of other scaling procedures in dosimetry with electron beams at therapeutic energies. (author)

Quantitative estimation of carbonation and chloride penetration in reinforced concrete by laser-induced breakdown spectroscopy

Science.gov (United States)

Eto, Shuzo; Matsuo, Toyofumi; Matsumura, Takuro; Fujii, Takashi; Tanaka, Masayoshi Y.

2014-11-01

The penetration profile of chlorine in a reinforced concrete (RC) specimen was determined by laser-induced breakdown spectroscopy (LIBS). The concrete core was prepared from RC beams with cracking damage induced by bending load and salt water spraying. LIBS was performed using a specimen that was obtained by splitting the concrete core, and the line scan of laser pulses gave the two-dimensional emission intensity profiles of 100 × 80 mm2 within one hour. The two-dimensional profile of the emission intensity suggests that the presence of the crack had less effect on the emission intensity when the measurement interval was larger than the crack width. The chlorine emission spectrum was measured without using the buffer gas, which is usually used for chlorine measurement, by collinear double-pulse LIBS. The apparent diffusion coefficient, which is one of the most important parameters for chloride penetration in concrete, was estimated using the depth profile of chlorine emission intensity and Fick's law. The carbonation depth was estimated on the basis of the relationship between carbon and calcium emission intensities. When the carbon emission intensity was statistically higher than the calcium emission intensity at the measurement point, we determined that the point was carbonated. The estimation results were consistent with the spraying test results using phenolphthalein solution. These results suggest that the quantitative estimation by LIBS of carbonation depth and chloride penetration can be performed simultaneously.

The magnetic flux leakage measurement by the hall sensor in the longitudinal magnetic field

International Nuclear Information System (INIS)

Joo, Gwang Tae; Son, Dae Rok; Han, Jung Hee; Park, Jae Hyung

1998-01-01

This paper is concerned with magnetic leakage flux measurement using by the hall sensor in the longitudinal magnetic field of the feromagnetic specimen. For detection sensitivity by the hall probe according to various depth of the subsurface defects, the specimen are prepared by six drilled holes of 0.5 mm φ from 1 mm depth to 4 mm depth in the carbon steel plate(10 x 35 x 265 mm). When the specimen applied by various frequency(2 - 9 Hz) of the AC through synthesizer and power amplifier in the yoke, the signals of the magnetic flux leakage using lack-in amplifier and synthesizer are decreased linearly with defect depth at 2 Hz, but these signals are decreased suddenly with defect depth from the surface and obscured with increasing frequency. And, when the specimen applied range of 1 Amp. to 5 Amp. by DC power supply in the yoke, the signals of the magnetic flux leakage through DVM decreased linearly with defect depth up to 2.5 mm depth and change slightly defect depth above 2.5 mm depth from the surface, but its signals appeared predominately.

A Study to Increase Weld Penetration in P91 Steel During TIG Welding by using Activating Fluxes

Science.gov (United States)

Singh, Akhilesh Kumar; Kumar, Mayank; Dey, Vidyut; Naresh Rai, Ram

2017-08-01

Activated Flux TIG (ATIG) welding is a unique joining process, invented at Paton Institute of electric welding in 1960. ATIG welding process is also known as flux zoned TIG (FZTIG). In this process, a thin layer of activating flux is applied along the line on the surface of the material where the welding is to be carries out. The ATIG process aids to increase the weld penetration in thick materials. Activating fluxes used in the literature show the use of oxides like TiO2, SiO2, Cr2O3, ZnO, CaO, Fe2O3, and MnO2 during welding of steels. In the present study, ATIG was carried out on P-91 steel. Though, Tungsten Inert Gas welding gives excellent quality welds, but the penetration obtained in such welding is still demanding. P91 steel which is ferritic steel is used in high temperature applications. As this steel is, generally, used in thick sections, fabrication of such structures with TIG welding is limited, due to its low depth of penetration. To increase the depth of penetration in P91while welding with ATIG, the role of various oxides were investigated. Apart from the oxides mentioned above, in the present study the role of B2O3, V2O5 and MgO, during ATIG welding of P91 was investigated. It was seen that, compared to TIG welding, there was phenomenal increase in weld penetration during ATIG welding. Amongst all the oxides used in this study, maximum penetration was achieved in case of B2O3. The measurements of weld penetration, bead width and heat affected zone of the weldings were carried out using an image analysis technique.

Penetrators for delivering Scientific equipment to minor bodies by flying-pass missions.

Science.gov (United States)

Bagrov, Alexander; Martynov, Maxim; Pichkhadze, Konstantin M.; Dolgopolov, Vladimir; Sysoev, Valentin

Many space missions are planned to have close encounters with Solar system minor bodies as a pass-fly. Short time of such close encounters were effectively used for photographing of these bodies, i.e. for distant investigations only because of large velocities of the encounter. We propose to use high-velocity penetrators to provide contact investigations of the minor bodies in situ. These devices were designed by Lavochkin Association for lunar missions. They were designed for long lived scientific equipment to be placed under surface up to depth 2...3 m. Penetrators could survive under 500 g shock, so the contact velocity was from 90 to 250 m/s, so each of them had booster engine to decelerate orbital velocity. As flying-pass velocity near minor body can be more then 10 km/s, penetrators would hit target at speed above 1 km/s and successfully bear 1500 g. To do so we propose to fulfill whole internal space inside penetrator with distilled water and froze it to temperature - 80°C or lower. At this temperature water ice is as hard as steel, so penetrator will plunge into target like armour-piercing shell. After landing protective ice will be evaporated (particularly due to heating from collision) and all sensitive mechanics will be set free.

Correlation Between Cone Penetration Rate And Measured Cone Penetration Parameters In Silty Soils

DEFF Research Database (Denmark)

Poulsen, Rikke; Nielsen, Benjaminn Nordahl; Ibsen, Lars Bo

2013-01-01

This paper shows, how a change in cone penetration rate affects the cone penetration measurements, hence the cone resistance, pore pressure, and sleeve friction in silty soil. The standard rate of penetration is 20 mm/s, and it is generally accepted that undrained penetration occurs in clay while...... drained penetration occurs in sand. When lowering the penetration rate, the soil pore water starts to dissipate and a change in the drainage condition is seen. In intermediate soils such as silty soils, the standard cone penetration rate may result in a drainage condition that could be undrained......, partially or fully drained. However, lowering the penetration rate in silty soils has a great significance because of the soil permeability, and only a small change in penetration rate will result in changed cone penetration measurements. In this paper, analyses will be done on data from 15 field cone...

Magnetic focusing of an intense slow positron beam for enhanced depth-resolved analysis of thin films and interfaces

CERN Document Server

Falub, C V; Mijnarends, P E; Schut, H; Veen, A V

2002-01-01

The intense reactor-based slow positron beam (POSH) at the Delft research reactor has been coupled to a Two-Dimensional Angular Correlation of Annihilation Radiation (2D-ACAR) setup. The design is discussed with a new target chamber for the 2D-ACAR setup based on Monte Carlo simulations of the positron trajectories, beam energy distribution and beam transmission in an increasing magnetic field gradient. Numerical simulations and experiment show that when the slow positron beam with a FWHM of 11.6 mm travels in an increasing axial magnetic field created by a strong NdFeB permanent magnet, the intensity loss is negligible above approx 6 keV and a focusing factor of 5 in diameter is achieved. Monte Carlo simulations and Doppler broadening experiments in the target region show that in this configuration the 2D-ACAR setup can be used to perform depth sensitive studies of defects in thin films with a high resolution. The positron implantation energy can be varied from 0 to 25 keV before entering the non-uniform mag...

Nonlocal electrodynamics and low-temperature magnetization of clean high-κ superconductors

International Nuclear Information System (INIS)

Kogan, V.G.; Gurevich, A.; Cho, J.H.; Johnston, D.C.; Xu, M.; Thompson, J.R.; Martynovich, A.

1996-01-01

We show that magnetic properties of clean superconductors with a large Ginzburg-Landau parameter κ at low temperatures are affected by the nonlocality of the microscopic current-field relation and can be described by modified London equations. We argue that for clean materials at low temperatures, the standard London formula for the reversible magnetization in intermediate fields, M∼ln(H c2 /B), should contain the field H 0 ∼φ 0 /ρ 2 instead of H c2 ∼φ 0 /ξ 2 (T), with ρ being the nonlocality range on the order of ξ 0 , the zero-T coherence length. Since ρ depends weakly on T, the magnetization should exhibit an approximate scaling M(T,B)=X(T)Y(B) as observed in Bi- and Tl-based compounds in a broad temperature domain well below T c . Our expression for the magnetization reduces to the standard London result near T c and at any temperature for the dirty case. Implications of our results for interpretation of neutron scattering data and for procedures of extracting the penetration depth are discussed. copyright 1996 The American Physical Society

Surface-Adaptive, Antimicrobially Loaded, Micellar Nanocarriers with Enhanced Penetration and Killing Efficiency in Staphylococcal Biofilms

NARCIS (Netherlands)

Liu, Yong; Busscher, Henk J; Zhao, Bingran; Li, Yuanfeng; Zhang, Zhenkun; van der Mei, Henny C; Ren, Yijin; Shi, Linqi

Biofilms cause persistent bacterial infections and are extremely recalcitrant to antimicrobials, due in part to reduced penetration of antimicrobials into biofilms that allows bacteria residing in the depth of a biofilm to survive antimicrobial treatment. Here, we describe the preparation of

Three-dimensional architecture and development of Danianbryozoan mounds at Limhamn, south-west Sweden, usingground-penetrating radar

DEFF Research Database (Denmark)

Nielsen, Lars; Schack von Brockdorff, A.; Bjerager, Morten Gustav Erik

2009-01-01

in the Limhamn limestone quarry, south-west Sweden, obtained from combined reflected ground-penetrating radar signals and outcrop analysis provide new information about the architecture and growth development of such mounds. The mounds are composed of bryozoan limestone and dark-grey to black flint bands which...... outline mound geometries. Ground-penetrating radar data sections are collected over a 120 m by 60 m grid of data lines with trace spacing of 0·25 m, providing a depth penetration of 7 to 12 m and a vertical resolution of ca 0·30 m. The ground-penetrating radar images outline the geometry of the internal...... layering of the mounds which, typically, have widths and lengths of 30 to 60 m and heights of 5 to 10 m. Mound architecture and growth show great variability in the ground-penetrating radar images. Small-scale mound structures with a palaeorelief of only a few metres may constitute the basis for growth...

Intermittent Flux Penetration at Different Temperatures in YBa2Cu3O7−x on NdGaO3 Substrates

DEFF Research Database (Denmark)

Qviller, Atle Jorstad; Yurchenko, Vitaliy; Vestgården, Jørn Inge

2011-01-01

In type-II superconductors, increasing applied magnetic field penetrates gradually in the form of magnetic vortices. It is of great interest to understand the dynamics of magnetic flux in different superconducting materials, as this phenomenon can severely limit the performance of superconductors...

Magnetic and electronic properties of YBa sub 2 Cu sub 3 O sub x (6. 5

Energy Technology Data Exchange (ETDEWEB)

Puempin, B.; Keller, H.; Kuendig, W.; Savic, I.M.; Schneider, J.W.; Simmler, H.; Zimmermann, P. (Physik-Inst., Univ. Zurich (Switzerland)); Kaldis, E.; Rusiecki, S. (Lab. fuer Festkoerperphysik, ETH Zurich (Switzerland)); Rossel, C. (IBM Research Div., Zurich Research Lab., Rueschlikon (Switzerland)); Forgan, E.M. (School of Physics and Space Research, Univ. of Birmingham (UK))

1990-10-15

A systematic study of the local magnetic field distribution p(B) in the perovskite-type superconductor YBa{sub 2}Cu{sub 3}O{sub x} is presented. Special attention is given to the second moment <{Delta}B{sup 2}> of p(B) which is closely related to the superconducting carrier density n{sub s} and the effective mass m{sup *} of the superconducting carriers. The influence of temperature, anisotropy and hole doping are investigated in detail. It is found that the temperature dependence of the magnetic penetration depth in YBa{sub 2}Cu{sub 3}O{sub x} is in agreement with conventional s-wave pairing and suggests strong coupling. The anisotropic behavior of p(B) is well described by a theory for uniaxial type II superconductors, with an anisotropy ratio {gamma}{approx equal}5(1). Moreover, the zero-temperature values {lambda}{sub ab}(0)=130(10) nm and {lambda}{sub c}(0){approx equal}500-800 nm (penetration depth for screening currents flowing in the ab-planes and along the c-axis, respectively) were extracted from our data. {mu}SR experiments performed on oxygen deficient samples indicate that the structural and electronic properties of YBa{sub 2}Cu{sub 3}O{sub x} are strongly correlated via the oxygen content x. (orig.).

Analysis of the penetration of a caffeine containing shampoo into the hair follicles by in vivo laser scanning microscopy

Science.gov (United States)

Lademann, J.; Richter, H.; Schanzer, S.; Klenk, A.; Sterry, W.; Patzelt, A.

2010-02-01

In previous in vitro investigations, it was demonstrated that caffeine is able to stimulate the hair growth. Therefore, a penetration of caffeine into the hair follicle is necessary. In the present study, in vivo laser scanning microscopy (LSM) was used to investigate the penetration and storage of a caffeine containing shampoo into the hair follicles. It was shown that a 2-min contact time of the shampoo with the skin was enough to accumulate significant parts of the shampoo in the hair follicles. A penetration of the shampoo up to a depth of approx. 200 μm could be detected, which represents the detection limit of the LSM. At this depth, the close network of the blood capillaries surrounding the hair follicles commences. Even after 24 h, the substance was still detectable in the hair follicles. This demonstrates the long-term reservoir function of the hair follicles for topically applied substances such as caffeine.

Predicting the Consequences of MMOD Penetrations on the International Space Station

Science.gov (United States)

Hyde, James; Christiansen, E.; Lear, D.; Evans

2018-01-01

The threat from micrometeoroid and orbital debris (MMOD) impacts on space vehicles is often quantified in terms of the probability of no penetration (PNP). However, for large spacecraft, especially those with multiple compartments, a penetration may have a number of possible outcomes. The extent of the damage (diameter of hole, crack length or penetration depth), the location of the damage relative to critical equipment or crew, crew response, and even the time of day of the penetration are among the many factors that can affect the outcome. For the International Space Station (ISS), a Monte-Carlo style software code called Manned Spacecraft Crew Survivability (MSCSurv) is used to predict the probability of several outcomes of an MMOD penetration-broadly classified as loss of crew (LOC), crew evacuation (Evac), loss of escape vehicle (LEV), and nominal end of mission (NEOM). By generating large numbers of MMOD impacts (typically in the billions) and tracking the consequences, MSCSurv allows for the inclusion of a large number of parameters and models as well as enabling the consideration of uncertainties in the models and parameters. MSCSurv builds upon the results from NASA's Bumper software (which provides the probability of penetration and critical input data to MSCSurv) to allow analysts to estimate the probability of LOC, Evac, LEV, and NEOM. This paper briefly describes the overall methodology used by NASA to quantify LOC, Evac, LEV, and NEOM with particular emphasis on describing in broad terms how MSCSurv works and its capabilities and most significant models.

Immersion technique as a tool for in-depth OCT imaging through human blood and body's interior tissues

Science.gov (United States)

Xu, Xiangqun; Tuchin, Valery V.; Wang, Ruikang K.

2001-05-01

The concept of refractive index matching used for the enhancement of optical penetration depth of the whole blood is discussed on the basis of in vitro studies using optical coherence tomography technique. It was found that blood optical clearing is defined not only by refractive index matching effect, but also by changes of RBC size and their aggregation ability when chemicals are added. Chemical agents studied include glycerol, propylene glycol, trazograph, and dextrans. For the hyperosmotic agents, the application of 6.5% glycerol into twice diluted blood reduces the total attenuation coefficient from 4.2/mm to 2.0/mm, and correspondingly increases the optical penetration at 820 nm up to 117%. Similar effects of increase in transmittance and decrease in light scattering are also demonstrated by various molecular detrans with the light penetration enhancement within a range between 52.1% and 150.5%. We also demonstrate that the use of biocompatible agents could enhance in-depth imaging of the human esophagus and stomach tissues.

Magnetic flux dynamics in superconducting materials

International Nuclear Information System (INIS)

Hernandez Nieves, Alexander

2004-01-01

The magnetization curves, the Bean-Livingston barrier in type I and type II superconductors, the ac magnetic response, the effects of thermal fluctuations on the magnetic behavior and the different dissipation mechanism at microwave frequencies are investigated in mesoscopic superconductors.For small mesoscopic samples we study the peaks and discontinuous jumps found in the magnetization as a function of magnetic field.To interpret these jumps we consider that vortices located inside the sample induce a reinforcement of the Bean- Livingston surface barrier at fields greater than the first penetration field Hp1.This leads to multiple penetration fields Hpi Hp1;Hp2;Hp3;... for vortex entrance in mesoscopic samples.For low-T c mesoscopic superconductors we found that the meta-stable states due to the surface barrier have a large half-life time, which leads to the hysteresis in the magnetization curves as observed experimentally.A very different behavior appears for high-T c mesoscopic superconductors where thermally activated vortex entrance/exit through surface barriers is frequent.This leads to a reduction of the magnetization and a non-integer average number of flux quanta penetrating the superconductor.At microwave frequencies we found that each vortex penetration event produces a significant suppression of the ac losses since the imaginary part of the ac susceptibility X ( H d c) as a function of the magnetic field (Hdc) increases before the penetration of vortices and then it decreases abruptly after vortices have entered into the sample.We show that nascent vortices (vortices that are partly inside the sample and nucleated at the surface) play an important role in the dynamic behavior of mesoscopic samples. In type I macroscopic superconductors with first-principles simulations of the TDGL equations we have been able to reproduce several features of the intermediate state observed in experiments.Particularly, droplet and striped patterns are obtained depending

Regolith thickness at the Chang'E-3 landing site from the Lunar Penetrating Radar and impact craters

Science.gov (United States)

Fa, W.; Zhu, M.-H.; Liu, T.

2015-10-01

The Chang'E-3 lunar penetrating radar (LPR) observations reveal a newly formed regolith layer (<1 m), an ejecta layer (~2-6 m), and a palaeoregolith layer (~4-9 m) from the surface to a depth of ~ 20 m. The thicknesses of the newly formed regolith layer and the palaeoregolith layer are consistent with the estimations based on the excavation depth and morphology of small fresh craters.

Depth dependent local structures in CoPt thin films

Energy Technology Data Exchange (ETDEWEB)

Souza-Neto, N M [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Ramos, A Y; Tolentino, H C N; Joly, Y, E-mail: aline.ramos@grenoble.cnrs.f [Institut Neel, CNRS et Univ. Joseph Fourier, BP 166, F-38042 Grenoble Cedex 9 (France)

2009-11-15

X-ray absorption spectroscopy (XAS) has been used to clarify the thickness-dependent magnetic properties in nanometric CoPt films. We get benefit from the variation of the sampling depth with the grazing angle to investigate the variations of the local order within the film. In order to properly reconstruct the 3D information the experiments were performed either in the in-plane as in the out-of-plane geometries and supported by ab initio calculations. A depth dependence in the chemical order is revealed and the magnetic behavior is interpreted within this framework.

Recent Advances in Skin Penetration Enhancers for Transdermal Gene and Drug Delivery.

Science.gov (United States)

Amjadi, Morteza; Mostaghaci, Babak; Sitti, Metin

2017-01-01

There is a growing interest in transdermal delivery systems because of their noninvasive, targeted, and on-demand delivery of gene and drugs. However, efficient penetration of therapeutic compounds into the skin is still challenging largely due to the impermeability of the outermost layer of the skin, known as stratum corneum. Recently, there have been major research activities to enhance the skin penetration depth of pharmacological agents. This article reviews recent advances in the development of various strategies for skin penetration enhancement. We show that approaches such as ultrasound waves, laser, and microneedle patches have successfully been employed to physically disrupt the stratum corneum structure for enhanced transdermal delivery. Rather than physical approaches, several non-physical route have also been utilized for efficient transdermal delivery across the skin barrier. Finally, we discuss some clinical applications of transdermal delivery systems for gene and drug delivery. This paper shows that transdermal delivery devices can potentially function for diverse healthcare and medical applications while further investigations are still necessary for more efficient skin penetration of gene and drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Hydrodynamic analysis and design of high-level radioactive waste disposal model penetrators

International Nuclear Information System (INIS)

Visintini, L.; Mazazzi, R.; Murray, C.N.

1991-01-01

The Commission of the European Communities is studying in the framework of the NEA/OECD Internationally Co-ordinational Seabed Programme the feasibility of using deep ocean sedimentary geological formations as a final disposal medium for vitrified high level waste and fuel elements. At present, two options are being considered for the embedment of such wastes in the sediment column, drilling and free fall penetrators. In the second case, the high level waste would be contained in specially designed drums which would be placed into torpedo-shaped projectiles. These penetrators would then be launched from a semi-submersible platform or ship and allowed to fall freely through the water column (≅ 5 km depth) and to bury themselves within the sediment column. The present article reports some work which has been carried out by the Joint Research Centre, Ispra Establishment on designing large model penetrators for tests at two sites in the North Atlantic

Role of nuclear penetration effects in spin assignments. [J, transitions, internal conversion

Energy Technology Data Exchange (ETDEWEB)

Sahota, H S [Punjabi Univ., Patiala (India). Dept. of Physics

1976-04-01

Nuclear penetrations have been found to affect the internal conversion process of the retarded magnetic dipole transitions. In all cases where the penetration coefficient has been found to be essentially different from unity the transition is 1-forbidden. This criterian has been applied to the case of 191 keV transition in /sup 197/Au where the spin of the 268 keV level could not be deduced uniquely by any of the existing methods. The result is that the 199 keV transition has a dynamic contribution to its internal conversion process with the penetration coefficient lambda = 5.5 +- 0.9. To illustrate the applicability of the criterian further two more cases namely that of the 92 keV transition in /sup 131/Cs and 182 keV transition in /sup 129/Cs are also included.

A study of the penetration of projectiles into marine sediments

International Nuclear Information System (INIS)

Boisson, J.Y.

1985-01-01

The work described in this document consists of three main parts: - Application, after having reviewed calculation methods and known codes, of a dynamic plasticity model based on the upper bound-method (with dissipated energy calculations by plastic deformations). The soil model used for this calculation is the Cambridge Clay Model. - Carrying out a programme of tests with instrumented small scale penetrators in centrifuge on a consolidated clay-target. The trials are done under 50 g, with projectiles, fired with an airgun at high impact velocity (50 m/s). The penetrators' instrumentation consists of either measuring acceleration, or tip force with strain gauges. - The mounting of a small instrumented penetrator for shallow water depth experimentations, with an accelerometer, and a local cell for tip resistance. A rapid electronic data acquisition system has been developed for these experimentations. The preliminary tests are done in a large tank filled with clay. The geotechnical characteristics of the clay are perfectly controlled. The tests performed under these conditions have shown the following observations: the rapid electronic data acquisition system works perfectly and could be used as a basic component for a deep water instrumentated penetrator; the results, obtained in these particular test conditions, are in a perfect agreement with the predictions of the model developed in the frame of this contract

Case depth in SAE 1020 steel using barkhausen noise

Directory of Open Access Journals (Sweden)

Alessandra Drehmer

2013-01-01

Full Text Available The most widely used thermochemical process for surface hardening of steels is case hardening. Using several different heat treatments, martensitic surface layers were formed on SAE 1020 steel into which carbon had been diffused. Case depths were measured by traditional destructive techniques. Barkhausen noise measurements were made and both the RMS Barkhausen pulse envelope and the fast Fourier transform (FFT were obtained from numerical calculation. The FFT amplitudes, functions of frequency, were associated with distance from the sample surface using the skin depth equation δ = 1/ (πfσµ½ , where f is the frequency of the electromagnetic wave, s is the electrical conductivity, and µ is the magnetic permeability. We define a normalized power index (NPI which can be used to estimate case depths. The NPI is discussed in relation to the sample microstructure and it is shown that the case depth is most easily determined when the magnetic properties of the surface layer and core are substantially different.

Performance of kevlar fibre-reinforced rubber composite armour against shaped-charge jet penetration

Directory of Open Access Journals (Sweden)

Xu-dong Zu

Full Text Available AbstractThe protective capability of the Kevlar fibre-reinforced rubber composite armour (KFRRCA at different obliquities is studied using depth-of-penetration experiments method against a 56 mm-diameter standard-shaped charge. Efficiency factors are calculated to evaluate the protection capability of the KFRRCA at different obliquities. Meanwhile, an X-ray experiment is used to observe the deformation, fracture, and scatter of the shaped-charge jet as it penetrates the composite armour. Finally, scanning electron microscopy (SEM is used to analyse the effect of the Kevlar fibre-reinforced rubber for the composite armour to resist jet penetration. The results showed that the KFEECA can be used as additional armour, because it has excellent protection capability, and it can disturb the stability of the middle part of the shaped charge jet (SCJ obviously especially when the armour at 30°and 68° obliquities.

Experimental test of magnetic photons

International Nuclear Information System (INIS)

Lakes, R.S.

2004-01-01

A 'magnetic' photon hypothesis associated with magnetic monopoles is tested experimentally. These photons are predicted to easily penetrate metal. Experimentally the optical transmittance T of a metal foil was less than 2x10-17. The hypothesis is not supported since it predicts T=2x10-12

A review of penetration mechanisms and dynamic properties of tungsten and depleted uranium penetrators

International Nuclear Information System (INIS)

Andrew, S.P.; Caligiuri, R.D.; Eiselstein, L.E.

1991-01-01

Kinetic energy penetrators must posses the best possible combination of hardness, stiffness, strength, and fracture toughness characteristics to be effective against modern armor systems. Over the last decade, depleted uranium (DU) and tungsten alloys have been the materials of choice for kinetic energy penetrators. Du and tungsten perform abut the same against semi-infinite targets, and DU outperforms tungsten penetrators in oblique, spaced array targets, but because of environmental and subsequent cost concerns, effort has focused on improving the performance of tungsten penetrators over the last few years. However, despite recent improvements in material properties, the penetration performance of tungsten still lags behind that of DU. One possible reason is the difference in deformation mechanisms at the leading edge of the penetrator during the penetration process-DU alloys tend to shear band and sharpen as they penetrate the target material, whereas tungsten penetrators tend to mushroom and blunt. As a first step to determine whether shear banding is truly the reason for superior DU performance, a review of the fabrication, high strain-rate properties, and penetration phenomena of penetrators manufactured from both tungsten and DU alloys. Specifically, the effects of composition, processing, and heat treatment on material properties and penetration mechanisms of these alloys are discussed

Storm time electric field penetration observed at mid-latitude

International Nuclear Information System (INIS)

Yeh, H.C.; Foster, J.C.; Rich, F.J.; Swider, W.

1991-01-01

During the height of the February 8-9, 1986, magnetic storm the Millstone Hill radar was in the evening local time sector (1600-2200 MLT). Radar observations indicate that high speed (>1,000 m s -1 ) westward ion flow penetrated deeply below 50 degree invariant latitude (Λ) and persisted for 6 hours between 2100 UT on February 8 and 0300 UT on February 9. The double-peaked ion convection feature was pronounced throughout the period, and the separation in the dual maxima ranged from 4 degree to 10 degree. The latitude positions of the high-latitude ion drift peak and the convection reversal varied in unison. The low-latitude ion drift peak (∼49 degree Λ or L =2.3) did not show significant universal time/magnetic local time (UT/MLT) variation in its latitude location but showed a decrease in magnitude during the initial recovery phase of the storm. Using simultaneous particle (30 eV-30 keV) precipitation data from the DMSP F6 and F7 satellites, the authors find the high-latitude ion drift peak to coincide with the boundary plasma sheet/central plasma sheet transition in the high ionospheric conductivity (>15 mho) region. The low-latitude ion drift peak lay between the equatorward edges of the electron and soft ( + dominated ring current energy density in magnetic latitude. The low-latitude ion drift peak is the low-altitude signature of the electric field shielding effect associated with ring current penetration into the outer layer of the storm time plasmasphere

Study on mixed convective flow penetration into subassembly from reactor hot plenum in FBRs

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, J.; Ohshima, H.; Kamide, H.; Ieda, Y. [Power Reactor and Nuclear Fuel Development Corporation, Ibaraki (Japan)

1995-09-01

Fundamental experiments using water were carried out in order to reveal the phenomenon of mixed convective flow penetration into subassemblies from a reactor`s upper plenum of fast breeder reactors. This phenomenon appears under a certain natural circulation conditions during the operation of the direct reactor auxiliary cooling system for decay heat removal and might influence the natural circulation head which determines the core flow rate and therefore affects the core coolability. In the experiment, a simplified model which simulates an upper plenum and a subassembly was used and the ultrasonic velocity profile monitor as well as thermocouples were applied for the simultaneous measurement of velocity and temperature distributions in the subassembly. From the measured data, empirical equations related to the penetration flow onset condition and the penetration depth were obtained using relevant parameters which were derived from dimensional analysis.

Necrosis of HepG2 cancer cells induced by the vibration of magnetic particles

Energy Technology Data Exchange (ETDEWEB)

Wang, Biran [Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France); Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Bienvenu, Céline [Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Mendez-Garza, Juan; Lançon, Pascal; Madeira, Alexandra [Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France); Vierling, Pierre [Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Di Giorgio, Christophe, E-mail: christophe.di-giorgio@unice.fr [Institut de Chimie de Nice, UMR 7272, Université de Nice Sophia Antipolis, CNRS, 28 Avenue de Valrose, F-06100 Nice (France); Bossis, Georges, E-mail: bossis@unice.fr [Laboratoire de Physique de la Matière Condensée (LPMC), CNRS UMR 7336, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France)

2013-10-15

Experiments of magnetolysis, i.e., destruction of cells induced with magnetic particles (MPs) submitted to the application of a magnetic field, were conducted on HepG2 cancer cells. We herein demonstrate the usefulness of combining anisotropic MPs with an alternative magnetic field in magnetolysis. Thus, the application of an alternative magnetic field of low frequency (a few Hertz) in the presence of anisotropic, submicronic particles allowed the destruction of cancer cells “in vitro”. We also show that a constant magnetic field is far less efficient than an oscillating one. Moreover, we demonstrate that, at equal particle volume, it is much more efficient to utilize spindle shaped particles rather than spherical ones. In order to get deeper insight into the mechanism of magnetolysis experiments, we performed a study by AFM, which strongly supports that the magnetic field induces the formation of clusters of particles becoming then large enough todamage cell membranes. - Highlights: • Magnetic force was applied on cancer cells through magnetic particles. • The penetration depth was predicted, both for spherical and ellipsoidal particles. • Alternative force was shown to damage the cells contrary to static force. • The effect of indentation of magnetic particles was compared to the one of AFM tips. • The damage was attributed to the formation of clusters of particles.

Neutron pole figures compared with magnetic preferred orientations of different rock types

International Nuclear Information System (INIS)

Hansen, Anke; Chadima, Martin; Cifelli, Francesca; Brokmeier, H.-G.Heinz-Guenter; Siemes, Heinrich

2004-01-01

Neutron diffraction is an excellent tool for pole figure measurement of rock samples. Due to high penetration depth of neutrons for most materials neutron diffraction represents an efficient tool to measure complete pole figures with reliable grain statistics even in coarse grained or inequi-granular materials. In the field of structural geology, the measurement of anisotropy of magnetic susceptibility is a standard technique to reveal the tectonic history of deformed rocks. The application of both techniques on still ongoing studies of Precambrian, Carboniferous and Quaternary rocks which are characterised by fundamental different tectonic evolutions and mineralogical compositions shows the wide field of relevance and importance of these methods in understanding tectonic processes in detail

Magnetic fluctuations on TR{sub 3}Ba{sub 5}Cu{sub 8}O{sub δ} (TR=Ho, Y and Yb) superconducting system

Energy Technology Data Exchange (ETDEWEB)

Supelano, G.I., E-mail: ivan.supelano@uptc.edu.co [Grupo de Superficies Electroquímica y Corrosión, Universidad Pedagógica y Tecnológica de Colombia (Colombia); Sarmiento Santos, A. [Grupo de Superficies Electroquímica y Corrosión, Universidad Pedagógica y Tecnológica de Colombia (Colombia); Parra Vargas, C.A. [Grupo de Física de Materiales, Universidad Pedagógica y Tecnológica de Colombia (Colombia)

2014-12-15

In this work, we report the production of TR{sub 3}Ba{sub 5}Cu{sub 8}O{sub δ} (TR=Ho, Y and Yb) superconducting system using a usual solid state reaction method. The irreversibility line and the analysis of magnetization fluctuations for TR{sub 3}Ba{sub 5}Cu{sub 8}O{sub δ} (TR=Ho, Y and Yb) system were investigated. The curves of magnetization ZFC–FC were measured in magnetic fields of the 100–4000 Oe to obtain the values for T{sup ⁎} and T{sub C} temperatures. The penetration depth and the coherence length parameters as a function of the applied magnetic field were obtained. The data of the magnetization excess ΔM(T, H) was analyzed from the curves of magnetization as a function of logarithm of applied field for different values of temperature in the corresponding range. The Bulavskii, Ledvij and Kogan theory was employed for this purpose which considers fluctuations effects in the free energy and into the equilibrium magnetization.

A Comparison of Different Corneal Iontophoresis Protocols for Promoting Transepithelial Riboflavin Penetration.

Science.gov (United States)

Gore, Daniel M; O'Brart, David P; French, Paul; Dunsby, Chris; Allan, Bruce D

2015-12-01

To measure corneal riboflavin penetration using different transepithelial iontophoresis protocols. Freshly enucleated rabbit eyes were divided into nine treatment groups of 4 eyes. One group, in which 0.1% wt/vol riboflavin was applied for 30 minutes without iontophoresis after corneal epithelial debridement, acted as a control. The remaining groups were treated with an intact epithelium using different riboflavin formulations and varying iontophoresis current, soak, and rinse times. After riboflavin application, eyes were snap frozen in liquid nitrogen. Corneal cross sections 35 μm thick were then imaged immediately by two-photon fluorescence microscopy, using image processing software to quantify stromal riboflavin concentration at different corneal depths. In the epithelium-on iontophoresis treatment groups, greater stromal riboflavin penetration was achieved with higher-concentration riboflavin solutions, greater iontophoresis dosage, and longer solution contact times. A protocol utilizing 0.25% wt/vol riboflavin with benzalkonium chloride (BAC) 0.01% and two cycles of applied current and subsequent soaking (1 mA 5 minutes, soak 5 minutes; 0.5 mA 5 minutes, soak 5 minutes) achieved similar stromal riboflavin penetration to epithelium-off controls. The best-performing non-BAC-containing protocol produced stromal riboflavin penetration approximately 60% that of epithelium-off controls. Riboflavin solutions containing saline resulted in minimal stromal penetration. Riboflavin loading within the epithelium was equivalent to or higher than that in the subjacent stroma, despite rinsing the ocular surface with balanced salt solution. Modified iontophoresis protocols can significantly improve transepithelial riboflavin penetration in experimental corneal collagen cross-linking.

Deuterium depth profiles in metals using imaging field desorption

International Nuclear Information System (INIS)

Panitz, J.A.

1976-01-01

Depth profiles of 80 eV deuterium ions implanted in-situ into (110) tungsten have been measured by Imaging, Field-Desorption Mass Spectrometry. The relative abundance of deuterium was measured from the surface to a depth of 300A with less than 3A depth resolution by controlled field-evaporation of the specimen, and time-of-flight mass spectroscopy. The position of the depth distribution maximum (57 +- 3A from the surface) is shown to be in close agreement with that predicted theoretically for low energy deuterium implants using an amorphous-solid model. Structure in the distribution is attributed to surface morphology and channeling phenomena in the near surface region. Implanted impurity species from the ion source and tungsten surface have also been observed. For C + , C 2+ and 0 + , penetration is limited to less than 30A, with abundance decreasing exponentially from the surface. These results are interpreted in the context of the CTR first-wall impurity problem, and are used to suggest a novel method for in-situ characterization of low energy plasma species in operating CTR devices

Effects on cerebral circulation of decimeter wave therapy and variable magnetic field in patients with hemiparesis of vascular and traumatic origin

Energy Technology Data Exchange (ETDEWEB)

Strelkova, N.I.; Gavrilkov, A.T.; Dyuzhilova, N.F.; Strel' tsova, Ye.N.

1981-08-01

Both the artherosclerotic process in the case of cerebrovascular accident and cerebral trauma lead to impairment of cerebral hemodynamics, blood and spinal fluid circulation, macroscopic and microscopic disturbances. Electromagnetic waves in the decimeter range (decimeter waves - DMW) and a variable magnetic field (VMF) were used to treat these processes. Treatment was delivered directly to the region of the cerebral lesion, on the basis of the penetrating capacity of DMW and VMF to a relatively great depth (7 to 9 and 4 to 7 cm, respectively). Results of these treatments are discussed.

Data processing and initial results of Chang'e-3 lunar penetrating radar

Science.gov (United States)

Su, Yan; Fang, Guang-You; Feng, Jian-Qing; Xing, Shu-Guo; Ji, Yi-Cai; Zhou, Bin; Gao, Yun-Ze; Li, Han; Dai, Shun; Xiao, Yuan; Li, Chun-Lai

2014-12-01

To improve our understanding of the formation and evolution of the Moon, one of the payloads onboard the Chang'e-3 (CE-3) rover is Lunar Penetrating Radar (LPR). This investigation is the first attempt to explore the lunar subsurface structure by using ground penetrating radar with high resolution. We have probed the subsurface to a depth of several hundred meters using LPR. In-orbit testing, data processing and the preliminary results are presented. These observations have revealed the configuration of regolith where the thickness of regolith varies from about 4 m to 6 m. In addition, one layer of lunar rock, which is about 330 m deep and might have been accumulated during the depositional hiatus of mare basalts, was detected.

Simultaneous surface and depth neural activity recording with graphene transistor-based dual-modality probes.

Science.gov (United States)

Du, Mingde; Xu, Xianchen; Yang, Long; Guo, Yichuan; Guan, Shouliang; Shi, Jidong; Wang, Jinfen; Fang, Ying

2018-05-15

Subdural surface and penetrating depth probes are widely applied to record neural activities from the cortical surface and intracortical locations of the brain, respectively. Simultaneous surface and depth neural activity recording is essential to understand the linkage between the two modalities. Here, we develop flexible dual-modality neural probes based on graphene transistors. The neural probes exhibit stable electrical performance even under 90° bending because of the excellent mechanical properties of graphene, and thus allow multi-site recording from the subdural surface of rat cortex. In addition, finite element analysis was carried out to investigate the mechanical interactions between probe and cortex tissue during intracortical implantation. Based on the simulation results, a sharp tip angle of π/6 was chosen to facilitate tissue penetration of the neural probes. Accordingly, the graphene transistor-based dual-modality neural probes have been successfully applied for simultaneous surface and depth recording of epileptiform activity of rat brain in vivo. Our results show that graphene transistor-based dual-modality neural probes can serve as a facile and versatile tool to study tempo-spatial patterns of neural activities. Copyright © 2018 Elsevier B.V. All rights reserved.

Organic magnetic field sensor

Energy Technology Data Exchange (ETDEWEB)

McCamey, Dane; Boehme, Christoph

2017-01-24

An organic, spin-dependent magnetic field sensor (10) includes an active stack (12) having an organic material with a spin-dependence. The sensor (10) also includes a back electrical contact (14) electrically coupled to a back of the active stack (12) and a front electrical contact (16) electrically coupled to a front of the active stack (12). A magnetic field generator (18) is oriented so as to provide an oscillating magnetic field which penetrates the active stack (12).

On the Use of Line Depth Ratios to Measure Starspot Properties on Magnetically Active Stars

Science.gov (United States)

O'Neal, Douglas

2006-07-01

Photometric and spectroscopic techniques have proven to be effective ways to measure the properties of dark, cool starspots on magnetically active stars. Recently, a technique was introduced using atomic line depth ratios (LDRs) to measure starspot properties. Carefully reproducing this technique using a new set of spectroscopic observations of active stars, we find that the LDR technique encounters difficulties, specifically by overestimating spot temperatures (because the atomic lines blend with titanium oxide absorption in cooler spots) and by not tightly constraining the filling factor of spots. While the use of LDRs for active star studies has great promise, we believe that these concerns need to be addressed before the technique is more widely applied. This paper includes data taken at McDonald Observatory of the University of Texas at Austin.

Rooting depth and root depth distribution of Trifolium repens × T. uniflorum interspecific hybrids.

Science.gov (United States)

Nichols, S N; Hofmann, R W; Williams, W M; van Koten, C

2016-05-20

Traits related to root depth distribution were examined in Trifolium repens × T. uniflorum backcross 1 (BC 1 ) hybrids to determine whether root characteristics of white clover could be improved by interspecific hybridization. Two white clover cultivars, two T. uniflorum accessions and two BC 1 populations were grown in 1 -m deep tubes of sand culture. Maximum rooting depth and root mass distribution were measured at four harvests over time, and root distribution data were fitted with a regression model to provide measures of root system shape. Morphological traits were measured at two depths at harvest 3. Root system shape of the hybrids was more similar to T. uniflorum than to white clover. The hybrids and T. uniflorum had a higher rate of decrease in root mass with depth than white clover, which would result in higher proportions of root mass in the upper profile. Percentage total root mass at 100-200 mm depth was higher for T. uniflorum than white clover, and for Crusader BC 1 than 'Crusader'. Roots of the hybrids and T. uniflorum also penetrated deeper than those of white clover. T. uniflorum had thicker roots at 50-100 mm deep than the other entries, and more of its fine root mass at 400-500 mm. The hybrids and white clover had more of their fine root mass higher in the profile. Consequently, T. uniflorum had a higher root length density at 400-500 mm than most entries, and a smaller decrease in root length density with depth. These results demonstrate that rooting characteristics of white clover can be altered by hybridization with T. uniflorum, potentially improving water and nutrient acquisition and drought resistance. Root traits of T. uniflorum are likely to be adaptations to soil moisture and fertility in its natural environment. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Current Status of the Japanese Penetrator Mission: LUNAR-A

Science.gov (United States)

Tanaka, S.; Shiraishi, H.; Fujimura, A.; Hayakawa, H.

The scientific objective of the LUNAR-A, Japanese Penetrator Mission, is to explore the lunar interior by seismic and heat-flow experiments. Two penetrators containing two seismometers (horizontal and vertical components) and heat-flow probes will be deployed from a spacecraft onto the lunar surface, one on the nearside and the other on the farside of the moon. The final impact velocity of the penetrator will be about 300m/sec; it will encounter a shock of about 8000 G at impact on the lunar surface. According to numerous experimental impact tests using model penetrators and a lunar regolith analog target, each penetrator is predicted to penetrate to a depth of 1 to 3 m. The data obtained by the penetrators will be transmitted to the earth station via the LUNAR-A mother spacecraft orbiting at an altitude of about 200 km. The penetrator is a missile-shaped instrument carrier, which is about 14cm in diameter, 75cm in length, and about 14kg in weight without attitude control system. It contains a two-component seismometer and heat flow probes together with other supporting instruments such as a tilt meter and an accelerometer. The seismic observations are expected to provide key data on the size of the lunar core, as well as data on deep lunar mantle structure. The heat flow measurements at two penetrator deployment sites will also provide important data on the thermal structure and bulk concentrations of heat-generating elements in the Moon. These data will provide much stronger geophysical constraints on the origin and evolution of the Moon than has been obtained so far. The LUNAR-A spacecraft was supposed to be launched in the summer of 2004, but it was postponed due to the necessity of a replacement of the valves used in the RCS propulsion system of the spacecraft, following a recall issued by the manufacturer who found a malfunction of similar valves. Then, the technological review boards by ISAS and JAXA recommended that both the more robustness of the

Magnetic field propagation in a two ion species planar plasma opening switch

International Nuclear Information System (INIS)

Strauss, H. R.; Doron, R.; Arad, R.; Rubinstein, B.; Maron, Y.; Fruchtman, A.

2007-01-01

Three fluid plasma evolution equations are applied to the problem of magnetic field propagation in a planar plasma opening switch. For certain initial conditions in which Hall parameter H∼1, magnetic field penetration due to the Hall field, initially, as expected, either opposes or adds to the hydromagnetic pushing, depending on the polarity of the magnetic field relative to the density gradient. Later, however, the plasma pushing by the magnetic field is found in the case studied here to modify the plasma density in a way that the density gradient tends to align with the magnetic field gradient, effectively turning off the Hall effect. The penetration of the magnetic field then ceases and plasma pushing becomes the dominant process

PENETRATION OF CONICAL INDENTER INTO FOUNDATION MATERIAL AT COMBINED PERCUSSION AND SUBSEQUENT ULTRASONIC IMPACTS

Directory of Open Access Journals (Sweden)

M. G. Kiselev

2012-01-01

Full Text Available The aim of this paper is theoretical and experimental studys of a percussion and subsequent ultrasonic impacts on the indenter depth penetration into material of rigid-plastic foundation.The obtained results allow us to estimate an influence of percussion (low-frequency and ultrasound (high-frequency component parameters on a charging process.

Evidence of Deep Water Penetration in Silica during Stress Corrosion Fracture

OpenAIRE

Lechenault, F.; Rountree, C. L.; Cousin, F.; Bouchaud, J.-P.; Ponson, L.; Bouchaud, E.

2011-01-01

We measure the thickness of the heavy water layer trapped under the stress corrosion fracture surface of silica using neutron reflectivity experiments. We show that the penetration depth is 65-85 \\aa ngstr\\"{o}ms, suggesting the presence of a damaged zone of $\\approx$ 100 \\aa ngstr\\"{o}ms extending ahead of the crack tip during its propagation. This estimate of the size of the damaged zone is compatible with other recent results.

A review of penetration mechanisms and dynamic properties of tungsten and depleted uranium penetrators

International Nuclear Information System (INIS)

Andrew, S.P.; Caligiuri, R.D.; Eiselstein, L.E.

1991-01-01

Over the last decade, depleted uranium (DU) and tungsten alloys have been the materials of choice for kinetic energy penetrators. However, despite improvements in mechanical properties in recent years, the penetration performance of tungsten still lags behind that of DU. One possible reason is the difference in deformation mechanisms- DU alloys tend to shear band as they penetrate the target material, whereas tungsten penetrators tend to mushroom. As a first step to determining whether shear banding is truly the reason for superior DU performance, a review and summary of the available information was performed. This paper presents a state-of-the-art review of the formulation, high strain- rate properties, and penetration phenomena of penetrators manufactured from both tungsten and DU alloys. Specifically, the effects of composition, processing, and heat treatment on mechanical properties and penetration mechanisms of these alloys are discussed. Penetration data and models for penetration mechanisms (in particular shear banding) are also presented, as well as the applicability of these models and their salient features

Successful adaptation of three-dimensional inversion methodologies for archaeological-scale, total-field magnetic data sets

Science.gov (United States)

Cheyney, S.; Fishwick, S.; Hill, I. A.; Linford, N. T.

2015-08-01

Despite the development of advanced processing and interpretation tools for magnetic data sets in the fields of mineral and hydrocarbon industries, these methods have not achieved similar levels of adoption for archaeological or very near surface surveys. Using a synthetic data set we demonstrate that certain methodologies and assumptions used to successfully invert more regional-scale data can lead to large discrepancies between the true and recovered depths when applied to archaeological-type anomalies. We propose variations to the current approach, analysing the choice of the depth-weighting function, mesh design and parameter constraints, to develop an appropriate technique for the 3-D inversion of archaeological-scale data sets. The results show a successful recovery of a synthetic scenario, as well as a case study of a Romano-Celtic temple in the UK. For the case study, the final susceptibility model is compared with two coincident ground penetrating radar surveys, showing a high correlation with the comparative depth slices. The new approach takes interpretation of archaeological data sets beyond a simple 2-D visual interpretation based on pattern recognition.

Paramagnetic particles carried by cell-penetrating peptide tracking of bone marrow mesenchymal stem cells, a research in vitro

International Nuclear Information System (INIS)

Liu Min; Guo Youmin; Wu Qifei; Yang Junle; Wang Peng; Wang Sicen; Guo Xiaojuan; Qiang Yongqian; Duan Xiaoyi

2006-01-01

The ability to track the distribution and differentiation of stem cells by high-resolution imaging techniques would have significant clinical and research implications. In this study, a model cell-penetrating peptide was used to carry gadolinium particles for magnetic resonance imaging of the mesenchymal stem cells. The mesenchymal stem cells were isolated from rat bone marrow by Percoll and identified by osteogenic differentiation in vitro. The cell-penetrating peptides labeled with fluorescein-5-isothiocyanate and gadolinium were synthesized by a solid-phase peptide synthesis method and the relaxivity of cell-penetrating peptide-gadolinium paramagnetic conjugate on 400 MHz nuclear magnetic resonance was 5.7311 ± 0.0122 mmol -1 s -1 , higher than that of diethylenetriamine pentaacetic acid gadolinium (p < 0.05). Fluorescein imaging confirmed that this new peptide could internalize into the cytoplasm and nucleus. Gadolinium was efficiently internalized into mesenchymal stem cells by the peptide in a time- or concentration-dependent fashion, resulting in intercellular T1 relaxation enhancement, which was obviously detected by 1.5 T magnetic resonance imaging. Cytotoxicity assay and flow cytometric analysis showed the intercellular contrast medium incorporation did not affect cell viability and membrane potential gradient. The research in vitro suggests that the newly constructed peptides could be a vector for tracking mesenchymal stem cells

Shuttle Imaging Radar - Physical controls on signal penetration and subsurface scattering in the Eastern Sahara

Science.gov (United States)

Schaber, G. G.; Mccauley, J. F.; Breed, C. S.; Olhoeft, G. R.

1986-01-01

Interpretation of Shuttle Imaging Radar-A (SIR-A) images by McCauley et al. (1982) dramatically changed previous concepts of the role that fluvial processes have played over the past 10,000 to 30 million years in shaping this now extremely flat, featureless, and hyperarid landscape. In the present paper, the near-surface stratigraphy, the electrical properties of materials, and the types of radar interfaces found to be responsible for different classes of SIR-A tonal response are summarized. The dominant factors related to efficient microwave signal penetration into the sediment blanket include (1) favorable distribution of particle sizes, (2) extremely low moisture content and (3) reduced geometric scattering at the SIR-A frequency (1.3 GHz). The depth of signal penetration that results in a recorded backscatter, here called 'radar imaging depth', was documented in the field to be a maximum of 1.5 m, or 0.25 of the calculated 'skin depth', for the sediment blanket. Radar imaging depth is estimated to be between 2 and 3 m for active sand dune materials. Diverse permittivity interfaces and volume scatterers within the shallow subsurface are responsible for most of the observed backscatter not directly attributable to grazing outcrops. Calcium carbonate nodules and rhizoliths concentrated in sandy alluvium of Pleistocene age south of Safsaf oasis in south Egypt provide effective contrast in premittivity and thus act as volume scatterers that enhance SIR-A portrayal of younger inset stream channels.

Examination techniques for non-magnetic rings

International Nuclear Information System (INIS)

Metala, M.J.; Kilpatrick, N.L.; Frank, W.W.

1990-01-01

Until the introduction of 18Mn18Cr rings a few years ago, most non-magnetic steel rings for generator rotors were made from 18Mn5Cr alloy steel, which is highly susceptible to stress corrosion cracking in the presence of water. This, the latest in a series of papers on the subject of non-magnetic rings by the authors' company, provides a discussion of nondestructive examination of 18Mn5Cr rings for stress corrosion distress. With rings on the rotor, fluorescent penetrant, ultrasonic and special visual techniques are applied. With rings off the rotor, the fluorescent penetrant technique is used, with and without stress enhancement

Quadruple Cone Coil with improved focality than Figure-8 coil in Transcranial Magnetic Stimulation

Science.gov (United States)

Rastogi, Priyam; Lee, Erik G.; Hadimani, Ravi L.; Jiles, David C.

Transcranial Magnetic Stimulation (TMS) is a non-invasive therapy which uses a time varying magnetic field to induce an electric field in the brain and to cause neuron depolarization. Magnetic coils play an important role in the TMS therapy since their coil geometry determines the focality and penetration's depth of the induced electric field in the brain. Quadruple Cone Coil (QCC) is a novel coil with an improved focality when compared to commercial Figure-8 coil. The results of this newly designed QCC coil are compared with the Figure-8 coil at two different positions of the head - vertex and dorsolateral prefrontal cortex, over the 50 anatomically realistic MRI derived head models. Parameters such as volume of stimulation, maximum electric, area of stimulation and location of maximum electric field are determined with the help of computer modelling of both coils. There is a decrease in volume of brain stimulated by 11.6 % and a modest improvement of 8 % in the location of maximum electric field due to QCC in comparison to the Figure-8 coil. The Carver Charitable Trust and The Galloway Foundation.

Calculation of optical properties of dental composites as a basis for determining color impression and penetration depth of laser light

Science.gov (United States)

Weniger, Kirsten K.; Muller, Gerhard J.

2005-03-01

In order to achieve esthetic dental restorations, there should be no visible difference between restorative material and treated teeth. This requires a match of the optical properties of both restorative material and natural teeth. These optical properties are determined by absorption and scattering of light emerging not only on the surface but also inside the material. Investigating different dental composites in several shades, a method has been developed to calculate the optical parameters absorption coefficient μa, scattering coefficient μs, anisotropy factor g and reduced scattering coefficient μs'. The method includes sample preparation and measurements of transmittance and reflectance in an integrating sphere spectrometer, followed by inverse Monte Carlo simulations. Determination of optical properties is more precise and comprehensive than with the previously used Kubelka Munk theory because scattering can be looked at separated into pure scattering with the scattering coefficient μs and its direction with the anisotropy factor g. Moreover the use of the inverse Monte Carlo simulation not only minimizes systematic errors and considers the scattering phase function, but also takes into account the measuring geometry. The compilation of a data pool of optical parameters now enables the application of further calculation models as a basis for optimization of the composition of new materials. For example, a prediction of the general color impression for multiple layers can be carried out as well as the calculation of the wavelength dependent penetration depths of light with regard to photo polymerization. Further applications are possible in the area of laser ablation.

Quantitative analysis of transcranial and intraparenchymal light penetration in human cadaver brain tissue.

Science.gov (United States)

Tedford, Clark E; DeLapp, Scott; Jacques, Steven; Anders, Juanita

2015-04-01

Photobiomodulation (PBM) also known as low-level light therapy has been used successfully for the treatment of injury and disease of the nervous system. The use of PBM to treat injury and diseases of the brain requires an in-depth understanding of light propagation through tissues including scalp, skull, meninges, and brain. This study investigated the light penetration gradients in the human cadaver brain using a Transcranial Laser System with a 30 mm diameter beam of 808 nm wavelength light. In addition, the wavelength-dependence of light scatter and absorbance in intraparenchymal brain tissue using 660, 808, and 940 nm wavelengths was investigated. Intact human cadaver heads (n = 8) were obtained for measurement of light propagation through the scalp/skull/meninges and into brain tissue. The cadaver heads were sectioned in either the transverse or mid-sagittal. The sectioned head was mounted into a cranial fixture with an 808 nm wavelength laser system illuminating the head from beneath with either pulsed-wave (PW) or continuous-wave (CW) laser light. A linear array of nine isotropic optical fibers on a 5 mm pitch was inserted into the brain tissue along the optical axis of the beam. Light collected from each fiber was delivered to a multichannel power meter. As the array was lowered into the tissue, the power from each probe was recorded at 5 mm increments until the inner aspect of the dura mater was reached. Intraparenchymal light penetration measurements were made by delivering a series of wavelengths (660, 808, and 940 nm) through a separate optical fiber within the array, which was offset from the array line by 5 mm. Local light penetration was determined and compared across the selected wavelengths. Unfixed cadaver brains provide good anatomical localization and reliable measurements of light scatter and penetration in the CNS tissues. Transcranial application of 808 nm wavelength light penetrated the scalp, skull, meninges, and brain

Extraordinary Magnetic Field Enhancement with Metallic Nanowire: Role of Surface Impedance in Babinet's Principle for Sub-Skin-Depth Regime

Science.gov (United States)

Koo, Sukmo; Kumar, M. Sathish; Shin, Jonghwa; Kim, Daisik; Park, Namkyoo

2009-12-01

We propose and analyze the “complementary” structure of a metallic nanogap, namely, the metallic nanowire for magnetic field enhancement. A huge enhancement of the field up to a factor of 300 was achieved. Introducing the surface impedance concept, we also develop and numerically confirm a new analytic theory which successfully predicts the field enhancement factors for metal nanostructures. Compared to the predictions of the classical Babinet principle applied to a nanogap, an order of magnitude difference in the field enhancement factor was observed for the sub-skin-depth regime nanowire.

Magnetic shielding of an inhomogeneous magnetic field source by a bulk superconducting tube

International Nuclear Information System (INIS)

Hogan, K; Fagnard, J-F; Wéra, L; Vanderheyden, B; Vanderbemden, P

2015-01-01

Bulk type-II irreversible superconductors can act as excellent passive magnetic shields, with a strong attenuation of low frequency magnetic fields. Up to now, the performances of superconducting magnetic shields have mainly been studied in a homogenous magnetic field, considering only immunity problems, i.e. when the field is applied outside the tube and the inner field should ideally be zero. In this paper, we aim to investigate experimentally and numerically the magnetic response of a high-T c bulk superconducting hollow cylinder at 77 K in an emission problem, i.e. when subjected to the non-uniform magnetic field generated by a source coil placed inside the tube. A bespoke 3D mapping system coupled with a three-axis Hall probe is used to measure the magnetic flux density distribution outside the superconducting magnetic shield. A finite element model is developed to understand how the magnetic field penetrates into the superconductor and how the induced superconducting shielding currents flow inside the shield in the case where the emitting coil is placed coaxially inside the tube. The finite element modelling is found to be in excellent agreement with the experimental data. Results show that a concentration of the magnetic flux lines occurs between the emitting coil and the superconducting screen. This effect is observed both with the modelling and the experiment. In the case of a long tube, we show that the main features of the field penetration in the superconducting walls can be reproduced with a simple analytical 1D model. This model is used to estimate the maximum flux density of the emitting coil that can be shielded by the superconductor. (paper)

Speech Understanding with a New Implant Technology: A Comparative Study with a New Nonskin Penetrating Baha System

OpenAIRE

Kurz, Anja; Flynn, Mark; Caversaccio, Marco; Kompis, Martin

2014-01-01

Objective. To compare hearing and speech understanding between a new, nonskin penetrating Baha system (Baha Attract) to the current Baha system using a skin-penetrating abutment. Methods. Hearing and speech understanding were measured in 16 experienced Baha users. The transmission path via the abutment was compared to a simulated Baha Attract transmission path by attaching the implantable magnet to the abutment and then by adding a sample of artificial skin and the external parts of the Baha...

Magnetic properties of the charged Anderson-Brinkman-Morel state: Absence of Hc1

International Nuclear Information System (INIS)

Kita, T.

1991-01-01

Magnetic properties of the charged Anderson-Brinkman-Morel state are investigated theoretically as a special case of time-reversal-symmetry-breaking superconductivity. The magnetic field is expressed as a superposition of the one from the supercurrent j s (r) and that from the magnetic moment l(r) due to the internal motion of each Cooper pair. This procedure enables us to get rid of the paradox in zero external field that the moments are ordered (l=const) with no magnetic field nor supercurrent, leading to a natural conclusion that there is indeed a field due to l(r) which is screened almost completely by j s (r). If the system size is large enough compared with the penetration depth, the direction l(r) changes gradually toward the surface and the current j s (r) flows over the bulk. This means that the system is essentially nonuniform and forms a coreless vortex in zero external field. As for the magnetization process, the lattice of coreless vortices grows from the infinitesimal external field without H c1 (i.e., no Meissner state), which is subsequently followed by the first-order transition to the lattice with cores. Finally, the transition to the normal state occurs at H c2 enhanced over that of the conventional type-II superconductor due to the field l. An example of the magnetization curve is also given

A Novel Method for Remote Depth Estimation of Buried Radioactive Contamination.

Science.gov (United States)

Ukaegbu, Ikechukwu Kevin; Gamage, Kelum A A

2018-02-08

Existing remote radioactive contamination depth estimation methods for buried radioactive wastes are either limited to less than 2 cm or are based on empirical models that require foreknowledge of the maximum penetrable depth of the contamination. These severely limits their usefulness in some real life subsurface contamination scenarios. Therefore, this work presents a novel remote depth estimation method that is based on an approximate three-dimensional linear attenuation model that exploits the benefits of using multiple measurements obtained from the surface of the material in which the contamination is buried using a radiation detector. Simulation results showed that the proposed method is able to detect the depth of caesium-137 and cobalt-60 contamination buried up to 40 cm in both sand and concrete. Furthermore, results from experiments show that the method is able to detect the depth of caesium-137 contamination buried up to 12 cm in sand. The lower maximum depth recorded in the experiment is due to limitations in the detector and the low activity of the caesium-137 source used. Nevertheless, both results demonstrate the superior capability of the proposed method compared to existing methods.

Physical Penetration Testing: A Whole New Story in Penetration Testing

NARCIS (Netherlands)

Dimkov, T.; Pieters, Wolter

2011-01-01

Physical penetration testing plays an important role in assuring a company that the security policies are properly enforced and that the security awareness of the employees is on the appropriate level. In physical penetration tests the tester physically enters restricted locations and directly

Data processing and initial results of Chang'e-3 lunar penetrating radar

International Nuclear Information System (INIS)

Su Yan; Feng Jian-Qing; Xing Shu-Guo; Li Han; Dai Shun; Xiao Yuan; Li Chun-Lai; Fang Guang-You; Ji Yi-Cai; Zhou Bin; Gao Yun-Ze

2014-01-01

To improve our understanding of the formation and evolution of the Moon, one of the payloads onboard the Chang'e-3 (CE-3) rover is Lunar Penetrating Radar (LPR). This investigation is the first attempt to explore the lunar subsurface structure by using ground penetrating radar with high resolution. We have probed the subsurface to a depth of several hundred meters using LPR. In-orbit testing, data processing and the preliminary results are presented. These observations have revealed the configuration of regolith where the thickness of regolith varies from about 4 m to 6 m. In addition, one layer of lunar rock, which is about 330 m deep and might have been accumulated during the depositional hiatus of mare basalts, was detected

Penetration depth of YBa2Cu3O7 measured by polarised neutron reflectometry

International Nuclear Information System (INIS)

Reynolds, J.M.; Nunez, V.; Boothroyd, A.T.; Bucknall, D.G.; Penfold, J.

1998-01-01

We have applied the technique of polarised neutron reflectometry (PNR) to investigate the magnetic field profile near the surface of YBa 2 Cu 3 O 7 films at 4.3 K. The samples comprised 700-1400 nm of c-axis oriented, single crystal YBa 2 Cu 3 O 7 deposited by laser ablation on SrTiO 3 substrates. The measurements were carried out on the CRISP reflectometer at the ISIS facility. The PNR technique measures the magnetic induction profile perpendicular to the surface, and so in our case the decay of flux in the c-direction was measured with a field applied parallel to the ab plane. We present preliminary data for the polarised and unpolarised reflectivity (orig.)

Electromagnetic response in kinetic energy driven cuprate superconductors: Linear response approach

International Nuclear Information System (INIS)

Krzyzosiak, Mateusz; Huang, Zheyu; Feng, Shiping; Gonczarek, Ryszard

2010-01-01

Within the framework of the kinetic energy driven superconductivity, the electromagnetic response in cuprate superconductors is studied in the linear response approach. The kernel of the response function is evaluated and employed to calculate the local magnetic field profile, the magnetic field penetration depth, and the superfluid density, based on the specular reflection model for a purely transverse vector potential. It is shown that the low temperature magnetic field profile follows an exponential decay at the surface, while the magnetic field penetration depth depends linearly on temperature, except for the strong deviation from the linear characteristics at extremely low temperatures. The superfluid density is found to decrease linearly with decreasing doping concentration in the underdoped regime. The problem of gauge invariance is addressed and an approximation for the dressed current vertex, which does not violate local charge conservation is proposed and discussed.

Geohydrology of rocks penetrated by test well USW H-6, Yucca Mountain, Nye County, Nevada

International Nuclear Information System (INIS)

Craig, R.W.; Reed, R.L.

1991-01-01

Test well USW H-6 is one of several wells drilled in the Yucca Mountain area near the southwestern part of the Nevada Test Site for investigations related to isolation of high-level nuclear waste. This well was drilled to a depth of 1,220 meters. Rocks penetrated are predominantly ash-flow tuffs of Tertiary age, with the principal exception of dacitic(?) lave penetrated at a depth from 877 to 1,126 meters. The composite static water level was about 526 meters below the land surface; the hydraulic head increased slightly with depth. Most permeability in the saturated zone is in two fractured intervals in Crater Flat Tuff. Based on well-test data using the transitional part of a dual-porosity solution, an interval of about 15 meters in the middle part of the Bullfrog Member of the Crater Flat Tuff has a calculated transmissivity of about 140 meters squared per day, and an interval of about 11 meters in the middle part of the Tram Member of the Crater Flat Tuff has a calculated transmissivity of about 75 meters squared per day. The upper part of the Bullfrog Member has a transmissivity of about 20 meters squared per day. The maximum likely transmissivity of any rocks penetrated by the test well is about 480 meters squared per day, based on a recharge-boundary model. The remainder of the open hole had no detectable production. Matrix hydraulic conductivity ranges from less than 5 x 10 -5 to 1 x 10 -3 meter per day. Ground water is a sodium bicarbonate type that is typical of water from tuffaceous rock of southern Nevada. The apparent age of the water is about 14,6000 years. 29 refs., 26 figs., 5 tabs

Control of spiking in partial penetration of electron beam welds. Final report, 1 October 1969--1 October 1976

International Nuclear Information System (INIS)

1976-01-01

An investigation of the penetration mechanism of high energy density electron beams and an evaluation of electron beam deflection as a method of penetration control are presented. A discussion of electron beam mechanics including several penetration theories is presented in the introduction and background. Slur radiographs made using a pinhole x-ray camera are evaluated to determine velocity and acceleration of the point of beam impingement. Methods of cavity closure are discussed with possible causes of surface sealing of the beam cavity. A method of penetration, after the cavity has closed, based on the curves relating velocity and acceleration to penetration distance is considered. An estimate of cavity pressure is made from the maximum acceleration of the beam-metal interface. A system using an x-ray detector coupled with a beam deflecting device is detailed and evaluated. As this is the first attempt at penetration control by beam deflection the investigation seeks only to determine the feasibility of the idea without attempting a thorough analysis of range of abilities or quality of welds made by such devices. Based on several specimens which are presented beam deflection appears capable of controlling penetration depth. It is hoped that the ideas presented here will inspire future research along these lines

Fokker-Planck modeling of current penetration during electron cyclotron current drive

International Nuclear Information System (INIS)

Merkulov, A.; Westerhof, E.; Schueller, F. C.

2007-01-01

The current penetration during electron cyclotron current drive (ECCD) on the resistive time scale is studied with a Fokker-Planck simulation, which includes a model for the magnetic diffusion that determines the parallel electric field evolution. The existence of the synergy between the inductive electric field and EC driven current complicates the process of the current penetration and invalidates the standard method of calculation in which Ohm's law is simply approximated by j-j cd =σE. Here it is proposed to obtain at every time step a self-consistent approximation to the plasma resistivity from the Fokker-Planck code, which is then used in a concurrent calculation of the magnetic diffusion equation in order to obtain the inductive electric field at the next time step. A series of Fokker-Planck calculations including a self-consistent evolution of the inductive electric field has been performed. Both the ECCD power and the electron density have been varied, thus varying the well known nonlinearity parameter for ECCD P rf [MW/m -3 ]/n e 2 [10 19 m -3 ] [R. W. Harvey et al., Phys. Rev. Lett 62, 426 (1989)]. This parameter turns out also to be a good predictor of the synergetic effects. The results are then compared with the standard method of calculations of the current penetration using a transport code. At low values of the Harvey parameter, the standard method is in quantitative agreement with Fokker-Planck calculations. However, at high values of the Harvey parameter, synergy between ECCD and E parallel is found. In the case of cocurrent drive, this synergy leads to the generation of large amounts of nonthermal electrons and a concomitant increase of the electrical conductivity and current penetration time. In the case of countercurrent drive, the ECCD efficiency is suppressed by the synergy with E parallel while only a small amount of nonthermal electrons is produced

Magnetic shield effect simulation of superconducting film shield covering directly coupled HTS dc-SQUID magnetometer

International Nuclear Information System (INIS)

Terauchi, N.; Noguchi, S.; Igarashi, H.

2011-01-01

A superconducting film shield over a SQUID ring improves the robustness of the SQUID with respect to magnetic noise. Supercurrent in the SQUID magnetometer and the superconducting film shield were simulated. The superconducting film shield reduces the influence of the external magnetic field on the SQUID ring. An HTS SQUID is a high sensitive magnetic sensor. In recent years, the HTS SQUID is widely used in various applications. In some applications, high robustness with respect to magnetic noise is required to realize stable operation at outside of a magnetic shielding room. The target of this paper is a directly coupled HTS dc-SQUID magnetometer. To enhance the robustness of the SQUID magnetometer, use of a superconducting thin film shield has been proposed. The magnetic field directly penetrating the SQUID ring causes the change of the critical current of Josephson junction, and then the SQUID magnetometer transitions into inoperative state. In order to confirm the magnetic shield effect of the superconducting film shield, electromagnetic field simulation with 3D edge finite element method was performed. To simulate the high temperature superconductor, E-J characteristics and c-axis anisotropy are considered. To evaluate the effect of the superconducting film shield, an external magnetic field which is supposed to be a magnetic noise is applied. From the simulation results, the time transition of the magnetic flux penetrating the SQUID ring is investigated and the effect of the superconducting film shield is confirmed. The amplitude of the magnetic flux penetrating the SQUID ring can be reduced to about one-sixth since the superconducting film shield prevents the magnetic noise from directly penetrating the SQUID ring.

Earth magnetism a guided tour through magnetic fields

CERN Document Server

Campbell, Wallace H

2001-01-01

An introductory guide to global magnetic field properties, Earth Magnetism addresses, in non-technical prose, many of the frequently asked questions about Earth''s magnetic field. Magnetism surrounds and penetrates our Earth in ways basic science courses can rarely address. It affects navigation, communication, and even the growth of crystals. As we observe and experience an 11-year solar maximum, we may witness spectacular satellite-destroying solar storms as they interact with our magnetic field. Written by an acknowledged expert in the field, this book will enrich courses in earth science, atmospheric science, geology, meteorology, geomagnetism, and geophysics. Contains nearly 200 original illustrations and eight pages of full-color plates.* Largely mathematics-free and with a wide breadth of material suitable for general readers* Integrates material from geomagnetism, paleomagnetism, and solar-terrestrial space physics.* Features nearly 200 original illustrations and 4 pages of colour plates

Pulsed-Field Magnetization Properties of Bulk Superconductors by Employment of Vortex-Type Coils

Science.gov (United States)

Deng, Z.; Shinohara, N.; Miki, M.; Felder, B.; Tsuzuki, K.; Watasaki, M.; Kawabe, S.; Taguchi, R.; Izumi, M.

Vortex-type magnetizing coils are gaining more and more attention to activate bulk superconductors in pulsed-field magnetization (PFM) studies, compared with solenoid-type ones. Following existing reports, we present experimental results of the different penetration patterns of magnetic flux between the two kinds of coils. It was found that the magnetic flux will primarily penetrate inside the bulk from the upper and lower surfaces by using vortex coils, rather than from the periphery in the case of solenoid coils. Moreover, the bulk submitted to a small pulsed-field excitation exhibits a similar field profile as the excitation field (convex or concave shape); a phenomenon named field memory effect. The use of vortex- or solenoid-type coils in PFM will pose an influence on the initial flux penetration patterns during the flux trapping processes, but both coils can finally excite the best conical trapped field shape of the bulk.

Rapid penetration into granular media visualizing the fundamental physics of rapid earth penetration

CERN Document Server

Iskander, Magued

2015-01-01

Rapid Penetration into Granular Media: Visualizing the Fundamental Physics of Rapid Earth Penetration introduces readers to the variety of methods and techniques used to visualize, observe, and model the rapid penetration of natural and man-made projectiles into earth materials. It provides seasoned practitioners with a standard reference that showcases the topic's most recent developments in research and application. The text compiles the findings of new research developments on the subject, outlines the fundamental physics of rapid penetration into granular media, and assembles a com

The Penetration of Solar Radiation Into Carbon Dioxide Ice

Science.gov (United States)

Chinnery, H. E.; Hagermann, A.; Kaufmann, E.; Lewis, S. R.

2018-04-01

Icy surfaces behave differently to rocky or regolith-covered surfaces in response to irradiation. A key factor is the ability of visible light to penetrate partially into the subsurface. This results in the solid-state greenhouse effect, as ices can be transparent or translucent to visible and shorter wavelengths, while opaque in the infrared. This can lead to significant differences in shallow subsurface temperature profiles when compared to rocky surfaces. Of particular significance for modeling the solid-state greenhouse effect is the e-folding scale, otherwise known as the absorption scale length, or penetration depth, of the ice. While there have been measurements for water ice and snow, pure and with mixtures, to date, there have been no such measurements published for carbon dioxide ice. After an extensive series of measurements we are able to constrain the e-folding scale of CO2 ice for the cumulative wavelength range 300 to 1,100 nm, which is a vital parameter in heat transfer models for the Martian surface, enabling us to better understand surface-atmosphere interactions at Mars' polar caps.

Levitation of a magnet over a flat type II superconductor

International Nuclear Information System (INIS)

Hellman, F.; Gyorgy, E.M.; Johnson, D.W. Jr.; O'Bryan, H.M.; Sherwood, R.C.

1988-01-01

Levitation of a magnet over a type II superconductor where the field at the superconductor exceeds H/sub c/ 1 is described and shown. The penetration and pinning of the flux lines in the superconductor cause the position of the magnet to be stable over a flat disk; a complete Meissner effect would make this position unstable. Furthermore, the observed dependence of the height of levitation on such variables as the thickness of the superconducting disk and the size of the magnet are consistent with a model described in this paper based on the energy cost of flux penetration through vortices and inconsistent with a Meissner effect model

A study on depth-scaling of plastic phantom in electron beam dosimetry

International Nuclear Information System (INIS)

Kojima, T.; Saitoh, H.; Kawachi, T.; Katayose, T.; Myojyoyama, A.

2005-01-01

In recommendations of several standard dosimetry, water is defined as the reference medium, however, the water substitute plastic phantoms are highly discouraged. Nevertheless, in the case of accurate chamber positioning in water is not possible, or no waterproof chamber is available, their use is permitted at beam qualities R 50 2 (E 0 pl obtained from a ratio of electron average penetration depth; z av , half value depth ratio; (R 50 ) w,m from Monte Carlo dose calculation and that from measurements, are compared each other. As a result, there are slight differences in depth-scaling factor between obtained from simulation results and from measurements. These results indicate that c pl has to be studied more detail for the sake of precise electron dosimetry in plastic phantoms. (author)

A global reference model of Curie-point depths based on EMAG2

Science.gov (United States)

Li, Chun-Feng; Lu, Yu; Wang, Jian

2017-03-01

In this paper, we use a robust inversion algorithm, which we have tested in many regional studies, to obtain the first global model of Curie-point depth (GCDM) from magnetic anomaly inversion based on fractal magnetization. Statistically, the oceanic Curie depth mean is smaller than the continental one, but continental Curie depths are almost bimodal, showing shallow Curie points in some old cratons. Oceanic Curie depths show modifications by hydrothermal circulations in young oceanic lithosphere and thermal perturbations in old oceanic lithosphere. Oceanic Curie depths also show strong dependence on the spreading rate along active spreading centers. Curie depths and heat flow are correlated, following optimal theoretical curves of average thermal conductivities K = ~2.0 W(m°C)-1 for the ocean and K = ~2.5 W(m°C)-1 for the continent. The calculated heat flow from Curie depths and large-interval gridding of measured heat flow all indicate that the global heat flow average is about 70.0 mW/m2, leading to a global heat loss ranging from ~34.6 to 36.6 TW.

Estimation of the depth of the thoracic epidural space in children using magnetic resonance imaging

Directory of Open Access Journals (Sweden)

Wani TM

2017-03-01

Full Text Available Tariq M Wani,1,2 Mahmood Rafiq,1 Arif Nazir,1 Hatem A Azzam,1 Usama Al Zuraigi,1 Joseph D Tobias2 1Department of Anesthesia, King Fahad Medical City, Riyadh, Saudi Arabia; 2Department of Anesthesiology and Pain Medicine, Nationwide Children’s Hospital, Columbus, OH, USA Background: The estimation of the distance from the skin to the thoracic epidural space or skin to epidural depth (SED may increase the success rate and decrease the incidence of complications during placement of a thoracic epidural catheter. Magnetic resonance imaging (MRI is the most comprehensive imaging modality of the spine, allowing for the accurate determination of tissue spaces and distances. The present study uses MRI-derived measurements to measure the SED and define the ratio between the straight and inclined SEDs at two thoracic levels (T6–7 and T9–10 in children.Methods: The T2-weighed sagittal MRI images of 109 children, ranging in age from 1 month to 8 years, undergoing radiological evaluation unrelated to spine pathology were assessed. The SEDs (inclined and straight were determined, and a comparison between the SEDs at two thoracic levels (T6–7 and T9–10 was made. Univariate and multivariate linear regression models were used to assess the relationship of the inclined thoracic T6–7 and T9–10 SED measurements with age, height, and weight.Results: Body weight demonstrated a stronger association with the SED than did the age or height with R2 values of 0.6 for T6–7 and 0.5 for T9–10. The formulae describing the relationship between the weight and the inclined SED were T6–7 inclined (mm = 7 + 0.9 × kg and T9–10 inclined (mm = 7 + 0.8 × kg.Conclusion: The depth of the pediatric thoracic epidural space shows a stronger correlation with weight than with age or height. Based on the MRI data, the predictive weight-based formulas can serve as guide to clinicians for placement of thoracic epidural catheters. Keywords: thoracic epidural space

Depth distribution of chemical phase concentration determined by grazing incidence X-ray diffraction

International Nuclear Information System (INIS)

Novak, P.; Ballo, P.; Dobrocka, E.; Vallo, M.; Lalinsky, T.

2013-01-01

Grazing incidence geometry is widely used in X-ray diffraction analysis of thin films. Penetration depth of radiation can be easily changed by an appropriate selection of the angle of incidence α that enables obtaining information from different depths of the sample. This depth can be decreased up to a nanometer scale by approaching the critical angle α_c for total external reflection. This method therefore provides an efficient tool for the analysis of depth distribution of various structural properties, such as the crystallite size, the amorphous fraction, stress or the concentration of chemical phase. However, absorption of the radiation can be characterized by an average attenuation coefficient μ a special care has to be paid to the last property. Variation of chemical phase concentration with depth usually results in depth dependence on the attenuation coefficient. In this contribution a method for determination of depth distribution of a chemical phase is outlined. The method correctly takes into account the depth variation of the attenuation coefficient. The method is tested on thin oxidized Ir layers. The aim of this paper is a comparison two simple model cases with the experimental results. (authors)

Verification of Sulfate Attack Penetration Rates for Saltstone Disposal Unit Modeling

Energy Technology Data Exchange (ETDEWEB)

Flach, G. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-05-12

Recent Special Analysis modeling of Saltstone Disposal Units consider sulfate attack on concrete and utilize degradation rates estimated from Cementitious Barriers Partnership software simulations. This study provides an independent verification of those simulation results using an alternative analysis method and an independent characterization data source. The sulfate penetration depths estimated herein are similar to the best-estimate values in SRNL-STI-2013-00118 Rev. 2 and well below the nominal values subsequently used to define Saltstone Special Analysis base cases.

Effects of magnetic order on the superconducting length scales and critical fields in single crystal ErNi2B2C

DEFF Research Database (Denmark)

Gammel, P.L.; Barber, B.P.; Ramirez, A.P.

1999-01-01

The flux line form factor in small angle neutron scattering and transport data determines the superconducting length scares and critical fields in single crystal ErNi2B2C. For H parallel to c, the coherence length xi increases and the penetration depth lambda decreases when crossing T-N = 6.0 K......, the Neel transition. The critical fields show corresponding anomalies near T-N. For H perpendicular to c, the fourfold modulation of the upper critical field H-c2 is strongly temperature dependent, changing sign near T-N, and can be modeled using the anisotropy of the sublattice magnetization....

The study of penetration of energetic ions in botanic samples with transmission measurements

International Nuclear Information System (INIS)

Wang, Y.G.; Chen, Q.Z.; Xue, J.M.; Du, G.H.; Qin, H.L; Zhang, W.M.; Yan, S.; Zhao, W.J.

2006-01-01

Botanic samples (onion endocuticles, kidney bean slices) were exposed to energetic ions. By recording transmission spectra, we studied the energy loss in such samples. Individual protrusion-like damage produced in highly oriented pyrolytic graphite (HOPG) substrate allowed us to analyze the mass density of the samples by scanning tunneling microscope (STM). The experimental results showed that the botanic sample is inhomogeneous in mass density, some incident ions lose only a small part of their energy after being stopped by a layer of botanic sample. Additionally, about 10 -7 of the incident ions with energy of tens of keV can penetrate through the botanic slice with a thickness of 50 μm. The dynamic change of the transmission spectrum of MeV heavy ions through a layer of botanic slice showed that the penetration ability of the incident ions increases with increasing ion fluence. These experimental results indicate that the inhomogeneousity of mass density of botanic samples and irradiation damage are the main reasons of the ultra-depth penetration of low-energy ions in such kind of botanic samples

Self-organization of magnetite nanoparticles in providing Saccharomyces cerevisiae Yeasts with magnetic properties

International Nuclear Information System (INIS)

Gorobets, S.V.; Yu, Gorobets O.; Demianenko, I.V.; Nikolaenko, R.N.

2013-01-01

The compared analyze of four methods of the magnetic nanoparticles clusters parameters estimation were developed and performed, such as, method, which takes into account two magneto-force scans of surface for calculation, geometry distance measurement between two centers of clusters in chains using the functions of NOVA-program, which is the standard computer equipment for scanning probe microscopy SOLVER PRO-M and the model, which takes into account the table meaning of magnetite magnetization and atomic-force microscopy. The magnetically-controllable biosorbent based on the culture of Saccharomyces cerevisiae was used as a model object for adequacy analyze of these models. As the result of the work we get the information about the depth of clusters penetration inside biomembrane, the typical sizes of clusters and the dispersion of magnetic clusters sizes. This analyze shows that all four methods can be used for single magnetic clusters, but for clusters, which lay in chains with small distance between their centers, the mode, which takes into account the table meaning of magnetite magnetization, cannot be used, because this model does not take into account the nearest neighbors contribution of interaction of magnetic fields dipole with magnetic probe. - Highlights: ► We have developed a mathematical model to determine the localization of magnetic phase in the vicinity of the membrane. ► We tried out this model on magnetically-based biosorbent yeast S. cerevisiae. ► We used magnetic force microscopy for the detection of magnetic phase in the biosorbent. ► As a result, it was shown that the magnetic phase is located on the membrane surface, which in turn allows us to estimate its size

Electron optics in hybrid photodetectors in magnetic fields

International Nuclear Information System (INIS)

Green, D.

1996-12-01

The CMS detector design has the hadronic calorimeter immersed in a 4 T magnetic field. The scintillator photon transducer must work reliably in this environment. The baseline phototransducer is the ''hybrid photomultiplier'', which consists of a standard photocathode (S20) followed by a high field acceleration onto the surface of a Si diode. Such a device has a linear response, 1 e out for every 3.6 eV of potential drop in excess of the threshold needed to penetrate the passivation layer of the diode. A threshold voltage of ∼2 kV is typical of these devices, leading to a gain of ∼2000 at 10 kV applied voltage. In the interest of reducing costs, the Si surface can be cut into pixels. However, the optics of the electron trajectories must be well understood so as to avoid crosstalk between pixels caused by misalignment of the accelerating electric field and the axis of the CMS magnetic field. The depletion depth of the Si is quite standard, ∼300 μm. The source capacity is ∼20 pF. The output pulse has a ∼6 nsec risetime for > 60 V diode biasing. The device is expected to be highly immune to magnetic field effects due to the short spacing, ∼3 mm, between photocathode and Si

Genetic Algorithm for Opto-thermal Skin Hydration Depth Profiling Measurements

Science.gov (United States)

Cui, Y.; Xiao, Perry; Imhof, R. E.

2013-09-01

Stratum corneum is the outermost skin layer, and the water content in stratum corneum plays a key role in skin cosmetic properties as well as skin barrier functions. However, to measure the water content, especially the water concentration depth profile, within stratum corneum is very difficult. Opto-thermal emission radiometry, or OTTER, is a promising technique that can be used for such measurements. In this paper, a study on stratum corneum hydration depth profiling by using a genetic algorithm (GA) is presented. The pros and cons of a GA compared against other inverse algorithms such as neural networks, maximum entropy, conjugate gradient, and singular value decomposition will be discussed first. Then, it will be shown how to use existing knowledge to optimize a GA for analyzing the opto-thermal signals. Finally, these latest GA results on hydration depth profiling of stratum corneum under different conditions, as well as on the penetration profiles of externally applied solvents, will be shown.

DETERMINATION OF SUPERFICIAL ABSORBED DOSE FROM EXTERNAL EXPOSURE OF WEAKLY PENETRATING RADIATIONS

Institute of Scientific and Technical Information of China (English)

陈丽姝

1994-01-01

The methods of determining the superficial absorbed dose distributions in a water phantom by means of the experiments and available theories have been reported.The distributions of beta dose were measured by an extrapolation ionization chamber at definite depthes corresponding to some superficial organs and tissues such as the radiosensitive layer of the skin,cornea,sclera,anterior chamber and lens of eyeball.The ratios among superficial absorbed dose D(0.07) and average absorbed doses at the depthes 1,2,3,4,5 and 6mm are also obtained with Cross's methods.They can be used for confining the deterministic effects of some superficial tissues and organs such as the skin and the components of eyeball for weakly penetrating radiations.

High-accuracy defect sizing for CRDM penetration adapters using the ultrasonic TOFD technique

International Nuclear Information System (INIS)

Atkinson, I.

1995-01-01

Ultrasonic time-of-flight diffraction (TOFD) is the preferred technique for critical sizing of throughwall orientated defects in a wide range of components, primarily because it is intrinsically more accurate than amplitude-based techniques. For the same reason, TOFD is the preferred technique for sizing the cracks in control rod drive mechanism (CRDM) penetration adapters, which have been the subject of much recent attention. Once the considerable problem of restricted access for the UT probes has been overcome, this inspection lends itself to very high accuracy defect sizing using TOFD. In qualification trials under industrial conditions, depth sizing to an accuracy of ≤ 0.5 mm has been routinely achieved throughout the full wall thickness (16 mm) of the penetration adapters, using only a single probe pair and without recourse to signal processing. (author)

Pedestal bifurcation and resonant field penetration at the threshold of edge-localized mode suppression in the DIII-D Tokamak.

Science.gov (United States)

Nazikian, R; Paz-Soldan, C; Callen, J D; deGrassie, J S; Eldon, D; Evans, T E; Ferraro, N M; Grierson, B A; Groebner, R J; Haskey, S R; Hegna, C C; King, J D; Logan, N C; McKee, G R; Moyer, R A; Okabayashi, M; Orlov, D M; Osborne, T H; Park, J-K; Rhodes, T L; Shafer, M W; Snyder, P B; Solomon, W M; Strait, E J; Wade, M R

2015-03-13

Rapid bifurcations in the plasma response to slowly varying n=2 magnetic fields are observed as the plasma transitions into and out of edge-localized mode (ELM) suppression. The rapid transition to ELM suppression is characterized by an increase in the toroidal rotation and a reduction in the electron pressure gradient at the top of the pedestal that reduces the perpendicular electron flow there to near zero. These events occur simultaneously with an increase in the inner-wall magnetic response. These observations are consistent with strong resonant field penetration of n=2 fields at the onset of ELM suppression, based on extended MHD simulations using measured plasma profiles. Spontaneous transitions into (and out of) ELM suppression with a static applied n=2 field indicate competing mechanisms of screening and penetration of resonant fields near threshold conditions. Magnetic measurements reveal evidence for the unlocking and rotation of tearinglike structures as the plasma transitions out of ELM suppression.

Review of progress in magnetic particle inspection

Science.gov (United States)

Eisenmann, David J.; Enyart, Darrel; Lo, Chester; Brasche, Lisa

2014-02-01

Magnetic particle inspection (MPI) has been widely utilized for decades, and sees considerable use in the aerospace industry with a majority of the steel parts being inspected with MPI at some point in the lifecycle. Typical aircraft locations inspected are landing gear, engine components, attachment hardware, and doors. In spite of its numerous applications the method remains poorly understood, and there are many aspects of that method which would benefit from in-depth study. This shortcoming is due to the fact that MPI combines the complicated nature of electromagnetics, metallurgical material effects, fluid-particle motion dynamics, and physiological human factors into a single inspection. To promote understanding of the intricate method issues that affect sensitivity, or to assist with the revision of industry specifications and standards, research studies will be prioritized through the guidance of a panel of industry experts, using an approach which has worked successfully in the past to guide fluorescent penetrant inspection (FPI) research efforts.

Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution

Science.gov (United States)

Oji, Tatsuo; Dornbos, Stephen Q.; Yada, Keigo; Hasegawa, Hitoshi; Gonchigdorj, Sersmaa; Mochizuki, Takafumi; Takayanagi, Hideko; Iryu, Yasufumi

2018-02-01

The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity of bioturbation in seafloor sediment known as the `agronomic revolution'. This bioturbation transition was coupled with a shift in dominant trace fossil style from horizontal surficial traces in the late Precambrian to vertically penetrative trace fossils in the Cambrian. Here we show the existence of the first vertically penetrative trace fossils from the latest Ediacaran: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Their Ediacaran age is established through stable carbon isotope chemostratigraphy and their occurrence stratigraphically below the first appearance of the trace fossil Treptichnus pedum. These Arenicolites are large in diameter, penetrate down to at least 4 cm into the sediment, and were presumably formed by the activity of bilaterian animals. They are preserved commonly as paired circular openings on bedding planes with maximum diameters ranging up to almost 1 cm, and as U- and J-shaped tubes in vertical sections of beds. Discovery of these complex penetrative trace fossils demonstrates that the agronomic revolution started earlier than previously considered.

Analysis of Reactor Vessel Lower Head Penetration Tube Failure

International Nuclear Information System (INIS)

Stempniewicz, Marek

1999-01-01

This paper presents results of two studies, performed to investigate the behavior of the reactor vessel penetration tubes in case of relocation of molten material into the tubes. The first study is on the CORVIS drain line experiment 03/1. Results of pre-test calculations are presented, and compared to the later obtained experimental data. The timing of the drain line melting and the velocity of the debris flowing inside the drain line were predicted correctly, but the penetration depth was clearly underestimated. If the calculations are done using different correlation for the melt-to-wall convective heat transfer, the results are closer to the experiment. It cannot however be concluded that the alternative correlation is more appropriate until other uncertainties are clarified. The second study presents calculations performed for GKN Dodewaard CRD, instrument tubes and drain line. Calculations were performed to estimate whether the tubes have a chance to withstand the first attack of the melt and thus postpone vessel failure until the water in the lower plenum evaporates. Calculations were performed assuming that the melt can move into the tubes without any resistance, e.g. presence of water in the tubes was not taken into account. The results indicate that the critical penetration of the GKN vessel, which is most likely to fail, is the drain line. Results also indicate that external flooding should prevent early tube failure, at least in case of low vessel pressure. (author)

Ground-penetrating radar study of the Rahivere peat bog, eastern Estonia

Directory of Open Access Journals (Sweden)

Jüri Plado

2011-03-01

Full Text Available The current case study presents results of the ground-penetrating radar (GPR profiling at one of the Saadjärve drumlin field interstitial troughs, the Rahivere bog, eastern Estonia. The study was conducted in order to identify the bog morphology, and the thickness and geometry of the peat body. The method was also used to describe the applicability of GPR in the evaluation of the peat deposit reserve as the Rahivere bog belongs among the officially registered peat reserves. Fourteen GPR profiles, ~ 100 m apart and oriented perpendicular to the long axis of the depression, covering the bog and its surrounding areas, were acquired. In order to verify the radar image interpretation as well as to evaluate the velocity of electromagnetic waves in peat, a common source configuration was utilized and thirteen boreholes were drilled on the GPR profiles. A mean value of 0.036 m ns–1 corresponding to relative dielectric permittivity of 69.7 was used for the time–depth conversion. Radar images reveal major reflection from the peat–soil interface up to a depth of about 4 m, whereas drillings showed a maximum thickness of 4.5 m of peat. Minor reflections appear from the upper peat and mineral soil. According to the borehole data, undecomposed peat is underlain by decomposed one, but identifying them by GPR is complicated. Mineral soil consists of glaciolimnic silty sand in the peripheral areas of the trough, overlain by limnic clay in the central part. The calculated peat volumes (1 200 000 m3 were found to exceed the earlier estimation (979 000 m3 that was based solely on drilling data. Ground-penetrating radar, as a method that allows mapping horizontal continuity of the sub-peat interface in a non-destructive way, was found to provide detailed information for evaluating peat depth and extent.

An analysis of depth dose characteristics of photon in water

International Nuclear Information System (INIS)

Buzdar, S.A.; Rao, M.A.; Nazir, A.

2009-01-01

Photon beam is most widely being used for radiation therapy. Biological effect of radiation is concerned with the evaluation of energy absorbed in the tissues. It was aimed to analyse the depth dose characteristics of x-ray beams of diverse energies to enhance the quality of radiotherapy treatment planning. Depth dose characteristics of different energy photon beams in water have been analysed. Photon beam is attenuated by the medium and the transmitted beam with less intensity causes lesser absorbed dose as depth increases. Relative attenuation on certain points on the beam axis and certain percentage of doses on different depths for available energies has been investigated. Photon beam depth dose characteristics do not show identical attributes as interaction of x-ray with matter is mainly governed by beam quality. Attenuation and penetration parameters of photon show variation with dosimetric parameters like field size due to scattering and Source to Surface Distance due to inverse square law, but the major parameter in photon interactions is its energy. Detailed analysis of photon Depth Dose characteristics helps to select appropriate beam for radiotherapy treatment when variety of beam energies available. Evaluation of this type of characteristics will help to establish theoretical relationships between dosimetric parameters to confirm measured values of dosimetric quantities, and hence to increase accuracy in radiotherapy treatment. (author)

Synthesis and study of the magnetic properties of thallium-based over-doped superconducting compounds

International Nuclear Information System (INIS)

Opagiste, C.

1994-07-01

The synthesis, structure and magnetic properties of the normal and superconducting states of over-doped Tl 2 Ba 2 Cu O 6±x and Tl 2 Ba 2 Ca Cu 2 O 8±x superconducting compounds, are presented. Synthesis under high pressure using Tl 2 Ba 2 O 5 as a precursor avoids thallium losses and Ba Cu O 2 formation. The entire over-doped region has been investigated (Tc ranging from 0 to 92 K) and the different stability zones for the two crystallographic structures have been explored. The orthorhombic structure is shown to be stoichiometric in cations, while the tetragonal one could present thallium deficiency. Clear correlations have been established between Tc and the lattice parameters for the two phases. It has been observed that the Meissner fraction increased with Tc and that the reversibility domain was more extended for samples having a Tc near the maximal value, which must be linked to the decrease of the anisotropy with over-doping. In the reversible regime, the mixed state is affected by thermal fluctuations around Tc. Evolution of the penetration depth with Tc is examined; it shows that the optimum doped compound (maximal Tc) behaves as a BCS type superconductor. The over-doping results in a penetration depth behaviour which strongly deviates from the standard model (BCS, two fluids). The zero temperature, obtained by extrapolation, seems to be independent of the over-doping. 54 figs., 3 tabs., 168 refs

Tumor penetrating peptides

Directory of Open Access Journals (Sweden)

Tambet eTeesalu

2013-08-01

Full Text Available Tumor-homing peptides can be used to deliver drugs into tumors. Phage library screening in live mice has recently identified homing peptides that specifically recognize the endothelium of tumor vessels, extravasate, and penetrate deep into the extravascular tumor tissue. The prototypic peptide of this class, iRGD (CRGDKGPDC, contains the integrin-binding RGD motif. RGD mediates tumor homing through binding to αv integrins, which are selectively expressed on various cells in tumors, including tumor endothelial cells. The tumor-penetrating properties of iRGD are mediated by a second sequence motif, R/KXXR/K. This C-end Rule (or CendR motif is active only when the second basic residue is exposed at the C-terminus of the peptide. Proteolytic processing of iRGD in tumors activates the cryptic CendR motif, which then binds to neuropilin-1 activating an endocytic bulk transport pathway through tumor tissue. Phage screening has also yielded tumor-penetrating peptides that function like iRGD in activating the CendR pathway, but bind to a different primary receptor. Moreover, novel tumor-homing peptides can be constructed from tumor-homing motifs, CendR elements and protease cleavage sites. Pathologies other than tumors can be targeted with tissue-penetrating peptides, and the primary receptor can also be a vascular zip code of a normal tissue. The CendR technology provides a solution to a major problem in tumor therapy, poor penetration of drugs into tumors. The tumor-penetrating peptides are capable of taking a payload deep into tumor tissue in mice, and they also penetrate into human tumors ex vivo. Targeting with these peptides specifically increases the accumulation in tumors of a variety of drugs and contrast agents, such as doxorubicin, antibodies and nanoparticle-based compounds. Remarkably the drug to be targeted does not have to be coupled to the peptide; the bulk transport system activated by the peptide sweeps along any compound that is

Impact of carpet construction on fluid penetration: The case of blood.

Science.gov (United States)

Feng, Chengcheng; Michielsen, Stephen; Attinger, Daniel

2018-03-01

Bloodstains and bloodstain patterns are often observed at crime scenes and their analysis through bloodstain pattern analysis (BPA) can assist in reconstructing crime scenes. However, most published work related to BPA only deals with hard, non-porous surfaces and none of the studies have carefully characterized carpets. Soft and porous carpets are often encountered at crime scenes since they are common in American homes accounting for 51% of total U.S. flooring market; this has motivated the research described herein. To assess fluid penetration into tufted carpers, a new method for determining porosity and pore size distribution in tufted carpets has been developed for bloodstains on carpet. In this study, three kinds of nylon carpet were used: a low, a medium and a high face-weight carpet. Each carpet had an antistain treatment, which was removed from half of each carpet by steam-cleaning with a pH 12 NaOH solution. This resulted in six carpet samples. Yarn twist, carpet weight, pile height, water contact angles on carpets, water contact angles on individual fibers, and fiber cross-sectional shapes were characterized. Porosity and pore size distribution were analyzed using confocal laser scanning microscopy (CLSM). Porcine blood was used as a human blood substitute at three liquid volumes (30μL, 10μL, and 2μL). Analysis showed that porous carpet construction and antistain finishing both affected penetration. The depth of blood penetration decreased with the increase of carpet face-weight but increased with increased drop height. The removal of antistain treatment increased blood penetration into the carpets and changed the pore size distribution. Effects of antistain treatment, porosity and pore size distribution of tufted carpet, and blood wicking behaviors on carpets were found to strongly affect blood penetration into the carpets. Copyright © 2018 Elsevier B.V. All rights reserved.

Theoretical aspects of magnetic helicity

International Nuclear Information System (INIS)

Hammer, J.H.

1985-01-01

The magnetic helicity, usually defined as K=integralA.Bdv, where A is the vector potential and B the magnetic field, measures the topological linkage of magnetic fluxes. Helicity manifests itself in the twistedness and knottedness of flux tubes. Its significance is that it is an ideal MHD invariant. While the helicity formalism has proven very useful in understanding reversed field pinch and spheromak behavior, some problems exist in applying the method consistently for complex (e.g., toroidal) conductor geometries or in situations where magnetic flux penetrates conducting walls. Recent work has attempted to generalize K to allow for all possible geometries

Development of a Deep-Penetrating, Compact Geothermal Heat Flow System for Robotic Lunar Geophysical Missions

Science.gov (United States)

Nagihara, Seiichi; Zacny, Kris; Hedlund, Magnus; Taylor, Patrick T.

2012-01-01

Geothermal heat flow measurements are a high priority for the future lunar geophysical network missions recommended by the latest Decadal Survey of the National Academy. Geothermal heat flow is obtained as a product of two separate measurements of geothermal gradient and thermal conductivity of the regolith/soil interval penetrated by the instrument. The Apollo 15 and 17 astronauts deployed their heat flow probes down to 1.4-m and 2.3-m depths, respectively, using a rotary-percussive drill. However, recent studies show that the heat flow instrument for a lunar mission should be capable of excavating a 3-m deep hole to avoid the effect of potential long-term changes of the surface thermal environment. For a future robotic geophysical mission, a system that utilizes a rotary/percussive drill would far exceed the limited payload and power capacities of the lander/rover. Therefore, we are currently developing a more compact heat flow system that is capable of 3-m penetration. Because the grains of lunar regolith are cohesive and densely packed, the previously proposed lightweight, internal hammering systems (the so-called moles ) are not likely to achieve the desired deep penetration. The excavation system for our new heat flow instrumentation utilizes a stem which winds out of a pneumatically driven reel and pushes its conical tip into the regolith. Simultaneously, gas jets, emitted from the cone tip, loosen and blow away the soil. Lab tests have demonstrated that this proboscis system has much greater excavation capability than a mole-based heat flow system, while it weighs about the same. Thermal sensors are attached along the stem and at the tip of the penetrating cone. Thermal conductivity is measured at the cone tip with a short (1- to 1.5-cm long) needle sensor containing a resistance temperature detector (RTD) and a heater wire. When it is inserted into the soil, the heater is activated. Thermal conductivity of the soil is obtained from the rate of temperature

Validation of a measuring technique with computed tomography for cement penetration into trabecular bone underneath the tibial tray in total knee arthroplasty on a cadaver model

International Nuclear Information System (INIS)

Verburg, Hennie; Ridder, Laurens C van de; Verhoeven, Vincent WJ; Pilot, Peter

2014-01-01

In total knee arthroplasty (TKA), cement penetration between 3 and 5 mm beneath the tibial tray is required to prevent loosening of the tibia component. The objective of this study was to develop and validate a reliable in vivo measuring technique using CT imaging to assess cement distribution and penetration depth in the total area underneath a tibia prosthesis. We defined the radiodensity ranges for trabecular tibia bone, polymethylmethacrylate (PMMA) cement and cement-penetrated trabecular bone and measured the percentages of cement penetration at various depths after cementing two tibia prostheses onto redundant femoral heads. One prosthesis was subsequently removed to examine the influence of the metal tibia prostheses on the quality of the CT images. The percentages of cement penetration in the CT slices were compared with percentages measured with photographs of the corresponding transversal slices. Trabecular bone and cement-penetrated trabecular bone had no overlap in quantitative scale of radio-density. There was no significant difference in mean HU values when measuring with or without the tibia prosthesis. The percentages of measured cement-penetrated trabecular bone in the CT slices of the specimen were within the range of percentages that could be expected based on the measurements with the photographs (p = 0.04). CT scan images provide valid results in measuring the penetration and distribution of cement into trabecular bone underneath the tibia component of a TKA. Since the proposed method does not turn metal elements into artefacts, it enables clinicians to assess the width and density of the cement mantle in vivo and to compare the results of different cementing methods in TKA

A Comparative Study Of Source Location And Depth Estimates From ...

African Journals Online (AJOL)

... the analytic signal amplitude (ASA) and the local wave number (LWN) of the total intensity magnetic field. In this study, a synthetic magnetic field due to four buried dipoles was analysed to show that estimates of source location and depth can be improved significantly by reducing the data to the pole prior to the application ...

High-resolution geophysical profiling using a stepped-frequency ground penetrating radar

Energy Technology Data Exchange (ETDEWEB)

Noon, D; Longstaff, D [The University of Queensland, (Australia)

1996-05-01

This paper describes the results of a ground penetrating radar (GPR) system which uses stepped-frequency waveforms to obtain high-resolution geophysical profiles. The main application for this system is the high-resolution mapping of thin coal seam structures, in order to assist surface mining operations in open-cut coal mines. The required depth of penetration is one meter which represents the maximum thickness of coal seams that are designated `thin`. A resolution of five centimeters is required to resolve the minimum thickness of coal (or shale partings) which can be economically recovered in an open-cut coal mine. For this application, a stepped-frequency GPR system has been developed, because of its ultrawide bandwidth (1 to 2 GHz) and high external loop sensitivity (155 dB). The field test results of the stepped-frequency GPR system on a concrete pavement and at two Australian open-cut coal mines are also presented. 7 refs., 5 figs.

Three dimensional live-cell STED microscopy at increased depth using a water immersion objective

Science.gov (United States)

Heine, Jörn; Wurm, Christian A.; Keller-Findeisen, Jan; Schönle, Andreas; Harke, Benjamin; Reuss, Matthias; Winter, Franziska R.; Donnert, Gerald

2018-05-01

Modern fluorescence superresolution microscopes are capable of imaging living cells on the nanometer scale. One of those techniques is stimulated emission depletion (STED) which increases the microscope's resolution many times in the lateral and the axial directions. To achieve these high resolutions not only close to the coverslip but also at greater depths, the choice of objective becomes crucial. Oil immersion objectives have frequently been used for STED imaging since their high numerical aperture (NA) leads to high spatial resolutions. But during live-cell imaging, especially at great penetration depths, these objectives have a distinct disadvantage. The refractive index mismatch between the immersion oil and the usually aqueous embedding media of living specimens results in unwanted spherical aberrations. These aberrations distort the point spread functions (PSFs). Notably, during z- and 3D-STED imaging, the resolution increase along the optical axis is majorly hampered if at all possible. To overcome this limitation, we here use a water immersion objective in combination with a spatial light modulator for z-STED measurements of living samples at great depths. This compact design allows for switching between objectives without having to adapt the STED beam path and enables on the fly alterations of the STED PSF to correct for aberrations. Furthermore, we derive the influence of the NA on the axial STED resolution theoretically and experimentally. We show under live-cell imaging conditions that a water immersion objective leads to far superior results than an oil immersion objective at penetration depths of 5-180 μm.

Experimental study on the penetration effect of ceramics composite projectile on ceramic / A3 steel compound targets

Directory of Open Access Journals (Sweden)

Di-qi Hu

2017-08-01

Full Text Available In order to improve the penetration of projectiles into ceramic composite armors, the nose of 30 mm standard projectile was replaced by a toughened ceramic nose, and the performance of ceramic-nose projectiles penetrating into ceramic/A3 steel composite targets has been experimentally researched. According to impact dynamics theory,, the performances of 30 mm ceramic-nose projectile and 30 mm standard projectile penetrating into the ceramic/A3 steel composite targets were analyzed and compared using DOP method, especially focusing on the effects made by different nose structures and materials. The aperture and depth of perforation of projectile into the armor plates as well as the residual mass of bullet core under the same conditions were comparatively analyzed. A numerical simulation was built and computed by ANSYS/LS-DYNA. Based on the simulated results, the penetration performance was further analyzed in terms of the residual mass of bullet core. The results show that the ceramic nose has a great effect on the protection of bullet core.

The Spatial Variability of Beryllium-7 Depth Distribution Study

International Nuclear Information System (INIS)

Jalal Sharib; Zainudin Othman; Dainee Nor Fardzila Ahmad Tugi; Noor Fadzilah Yusof; Mohd Tarmizi Ishak

2015-01-01

The objective of this paper is to study the spatial variability of 7 Be depth evolution in soil profile at two different sampling sites. The soil samples have been collected by using metal core in bare area in Bangi, Selangor and Timah Tasoh, Perlis , Malaysia. Two composite core samples for each sampling sites has been sectioned into 2 mm increments to a depth of 4 cm and oven dried at 45- 60 degree Celsius and gently desegregated. These two composite spatial samples are passed through a < 2 mm sieve and packed into proper geometry plastic container for 7 Be analysis by using gamma spectrometry with a 24-hour count time. From the findings, the 7 Be content in the soil samples from Bangi, Selangor study area is distributed lower depth penetration into the soil profile than Timah Tasoh, Perlis catchment due to many factors such as precipitation (fallout) and others. However, the spatial variability from both samples study area is also decreases exponentially with depth and is confined within the top few centimeters and similar with other works been reported (Blake et al., (2000) and Walling et al.,(2008). Furthermore, a detailed discussion from this study findings will be in full papers. (author)

Computational Analysis of Static and Dynamic Behaviour of Magnetic Suspensions and Magnetic Bearings

Science.gov (United States)

Britcher, Colin P. (Editor); Groom, Nelson J.

1996-01-01

Static modelling of magnetic bearings is often carried out using magnetic circuit theory. This theory cannot easily include nonlinear effects such as magnetic saturation or the fringing of flux in air-gaps. Modern computational tools are able to accurately model complex magnetic bearing geometries, provided some care is exercised. In magnetic suspension applications, the magnetic fields are highly three-dimensional and require computational tools for the solution of most problems of interest. The dynamics of a magnetic bearing or magnetic suspension system can be strongly affected by eddy currents. Eddy currents are present whenever a time-varying magnetic flux penetrates a conducting medium. The direction of flow of the eddy current is such as to reduce the rate-of-change of flux. Analytic solutions for eddy currents are available for some simplified geometries, but complex geometries must be solved by computation. It is only in recent years that such computations have been considered truly practical. At NASA Langley Research Center, state-of-the-art finite-element computer codes, 'OPERA', 'TOSCA' and 'ELEKTRA' have recently been installed and applied to the magnetostatic and eddy current problems. This paper reviews results of theoretical analyses which suggest general forms of mathematical models for eddy currents, together with computational results. A simplified circuit-based eddy current model proposed appears to predict the observed trends in the case of large eddy current circuits in conducting non-magnetic material. A much more difficult case is seen to be that of eddy currents in magnetic material, or in non-magnetic material at higher frequencies, due to the lower skin depths. Even here, the dissipative behavior has been shown to yield at least somewhat to linear modelling. Magnetostatic and eddy current computations have been carried out relating to the Annular Suspension and Pointing System, a prototype for a space payload pointing and vibration

Self-disclosure among bloggers: re-examination of social penetration theory.

Science.gov (United States)

Tang, Jih-Hsin; Wang, Cheng-Chung

2012-05-01

Based on Social Penetration theory, this study explores the topics that bloggers disclose on their blogs, and in the real world. A total of 1,027 Taiwanese bloggers participated in this online survey, which revealed that bloggers self-disclosed nine topics (attitude, body, money, work, feelings, personal, interests, experiences, and unclassified). Further, we examined the depth and width of what bloggers self-disclosed to three target audiences (online audience, best friend, and parents), confirming that their disclosure is significantly different for each of these target audiences. Bloggers seemingly express themselves to their best friends the most, followed by parents and online audiences, both in depth and in width. The "wedge model," proposed by Altman and Taylor (1973), has been extended to online relationships in this study. In comparison to male bloggers, female bloggers seemed to disclose more to their best friends and parents in their daily lives; however, no significant difference was observed in their disclosure to online audiences. Younger bloggers (<20 years old) seemed to disclose a wider range of topics; however, there was no significant difference in the depth of their disclosure on their blogs. Discussions of these results are also presented.

In-place HEPA filter penetration test

International Nuclear Information System (INIS)

Bergman, W.; Wilson, K.; Elliott, J.; Bettencourt, B.; Slawski, J.W.

1997-01-01

We have demonstrated the feasibility of conducting penetration tests on high efficiency particulate air (HEPA) filters as installed in nuclear ventilation systems. The in-place penetration test, which is designed to yield equivalent penetration measurements as the standard DOP efficiency test, is based on measuring the aerosol penetration of the filter installation as a function of particle size using a portable laser particle counter. This in-place penetration test is compared to the current in-place leak test using light scattering photometers for single HEPA filter installations and for HEPA filter plenums using the shroud method. Test results show the in-place penetration test is more sensitive than the in-place leak test, has a similar operating procedure, but takes longer to conduct. Additional tests are required to confirm that the in-place penetration test yields identical results as the standard dioctyl phthalate (DOP) penetration test for HEPA filters with controlled leaks in the filter and gasket and duct by-pass leaks. Further development of the procedure is also required to reduce the test time before the in- place penetration test is practical

Assessing the Penetrating Abilities of Experimental Preparation with Dental Infiltrant Features Using Optical Microscope: Preliminary Study.

Science.gov (United States)

Skucha-Nowak, Małgorzata; Machorowska-Pieniążek, Agnieszka; Tanasiewicz, Marta

2016-01-01

The aim of the infiltration technique is to penetrate demineralized enamel with a low viscosity resin. Icon® (DMG) is the first ever and so far the only dental infiltrant. Bacteriostaticity is one of the properties that should be inherent in dental infiltrants, but Icon lacks this feature. The aim of the preliminary study was to properly choose a dye which would allow us to assess the penetrating abilities of our own, experimental preparation with features of a dental infiltrant with bacteriostatic properties and to compare using an optical microscope the depth of infiltration of the designed experimental preparation with the infiltrant available on the market. The preparation is supposed to infiltrate decalcified human enamel and be assessed with an optical microscope. Eosin, neutral fuchsine and methylene blue were added to experimental preparation with dental infiltrant features and to Icon® (DMG) in order to assess the depth of penetration of the experimental solution into the decalcified layers of enamel. The experimental solution mixes well with eosin, neutral fuchsine, and methylene blue. During the preliminary study, the authors concluded that the experimental solution mixes well with methylene blue, neutral fuchsine, and eosin. An addition of eosin to a preparation which infiltrates inner, demineralized enamel layers, facilitates the assessment of such a preparation with an optical microscope. A designed experimental solution with the main ingredients, i.e., 2-hydroxyethyl methacrylate (HEMA) and tetraethylene glycol dimethacrylate (TEGDMA) with a ratio of 75% to 25% penetrates the demineralized (decalcified) inner parts of the enamel and polymerizes when exposed to light. In order to assess the infiltration of the experimental solution into the demineralized enamel layers, it is required to improve the measurement techniques that utilize optical microscopy.

Turbulent penetration in T-junction branch lines with leakage flow

Energy Technology Data Exchange (ETDEWEB)

Kickhofel, John, E-mail: kickhofel@lke.mavt.ethz.ch; Valori, Valentina, E-mail: v.valori@tudelft.nl; Prasser, H.-M., E-mail: prasser@lke.mavt.ethz.ch

2014-09-15

Highlights: • New T-junction facility designed for adiabatic high velocity ratio mixing studies. • Trends in scalar mixing RMS and average in branch line presented and discussed. • Turbulent penetration has unique power spectrum relevant to thermal fatigue. • Forced flow oscillations translate to peaks in power spectrum in branch line. - Abstract: While the study of T-junction mixing with branch velocity ratios of near 1, so called cross flow mixing, is well advanced, to the point of realistic reactor environment fluid–structure interaction experiments and CFD benchmarking, turbulent penetration studies remain an under-researched threat to primary circuit piping. A new facility has been constructed for the express purpose of studying turbulent penetration in branch lines of T-junctions in the context of the high cycle thermal fatigue problem in NPPs. Turbulent penetration, which may be the result of a leaking valve in a branch line or an unisolable branch with heat losses, induces a thermal cycling region which may result in high cycle fatigue damage and failures. Leakage flow experiments have been performed in a perpendicular T-junction in a horizontal orientation with 50 mm diameter main pipe and branch pipe at velocity ratios (main/branch) up to 400. Wire mesh sensors are used as a means of measuring the mixing scalar in adiabatic tests with deionized and tap water. The near-wall region of highest scalar fluctuations is seen to vary circumferentially and in depth in the branch a great deal depending on the velocity ratio. The power spectra of the mixing scalar in the region of turbulent penetration are found to be dominated by high amplitude fluctuations at low frequencies, of particular interest to thermal fatigue. Artificial velocity oscillations in the main pipe manifest in the mixing spectra in the branch line in the form of a peak, the magnitude of which grows with increasing local RMS.

Thermal Behavior of the Reactor Vessel Penetration Under External Vessel Cooling During a Severe Accident

International Nuclear Information System (INIS)

Kang, Kyoung-Ho; Park, Rae-Joon; Kim, Jong-Tae; Min, Byung-Tae; Lee, Ki-Young; Kim, Sang-Baik

2004-01-01

Experimental and analytical studies on the thermal behavior of reactor vessel penetration have been performed under external vessel cooling during a severe accident in the Korean next-generation reactor APR1400. Two types of tests, SUS-EXT and SUS-DRY with and without external vessel cooling, respectively, have been performed using sustained heating by an induction heater. Three tests have been carried out varying the cooling conditions at the vessel outer surface in the SUS-EXT tests. The experimental results have been thermally estimated using the LILAC computer code. The experimental results indicate that the inner surface of the vessel was ablated by the 45-mm thickness in the SUS-DRY test. Despite the total ablation of the welding material, the penetration was not ejected outside the vessel, which could be attributed to the thermal expansion of the penetration. Unlike the SUS-DRY test, the thickness of the ablation was ∼15 to 20 mm at most, so the welding was preserved in the SUS-EXT tests. It is concluded from the experimental results that the external vessel cooling highly affected the ablation configuration and the thermal behaviors of the vessel and the penetration. An increase in coolant mass flow rate from 0.047 to 0.152 kg/s had effects on the thermal behavior of the lower head vessel and penetration in the SUS-EXT tests. The LILAC analytical results on temperature distribution and ablation depth in the lower head vessel and penetration were very similar to the experimental results

Measurement of the magnetic field inside the holes of a drilled bulk high-Tc superconductor

Science.gov (United States)

Lousberg, Gregory P.; Fagnard, Jean-François; Noudem, Jacques G.; Ausloos, Marcel; Vanderheyden, Benoit; Vanderbemden, Philippe

2009-04-01

We use macroscopic holes drilled in a bulk YBCO superconductor to probe its magnetic properties in the volume of the sample. The sample is subjected to an AC magnetic flux with a density ranging from 30 to 130 mT and the flux in the superconductor is probed by miniature coils inserted in the holes. In a given hole, three different penetration regimes can be observed: (i) the shielded regime, where no magnetic flux threads the hole; (ii) the gradual penetration regime, where the waveform of the magnetic field has a clipped sine shape whose fundamental component scales with the applied field; and (iii) the flux concentration regime, where the waveform of the magnetic field is nearly a sine wave, with an amplitude exceeding that of the applied field by up to a factor of two. The distribution of the penetration regimes in the holes is compared with that of the magnetic flux density at the top and bottom surfaces of the sample, and is interpreted with the help of optical polarized light micrographs of these surfaces. We show that the measurement of the magnetic field inside the holes can be used as a local characterization of the bulk magnetic properties of the sample.

The Processing and Analysis of Lunar Penetrating Radar Channel-1 Data from Chang'E-3

Directory of Open Access Journals (Sweden)

Gao Yun-ze

2015-10-01

Full Text Available Lunar Penetrating Radar (LPR, which is one of the most important science payloads onboard the Chang'E-3 (CE-3 rover, is used to obtain electromagnetic image less than 100 m beneath the lunar surface. This paper describes the system composition and working mechanism of the LPR and presents a detailed analysis of its data. We investigated special signal-processing methods and present the result of channel-1 data. The result shows that the effective echo occurs at depths greater than 100 m. Moreover, an unusual reflection exists at depth of 40 m, which may be the boundary of two geological units beneath the lunar surface.

Slab Penetration vs. Slab Stagnation: Mantle Reflectors as an Indicator

Science.gov (United States)

Okeler, A.; Gu, Y. J.; Schultz, R.; Contenti, S. M.

2011-12-01

Subducting oceanic lithosphere along convergent margins may stagnate near the base of the upper mantle or penetrate into the lower mantle. These dynamic processes cause extensive thermal and compositional variations, which can be observed in terms of impedance contrast (reflectivity) and topography of mantle transition zone (MTZ) discontinuities, i.e., 410- and 660-km discontinuities. In this study, we utilize ~ 15000 surface-reflected shear waves (SS) and their precursory arrivals (S410S and S660S) to analyze subduction related deformations on mantle reflectivity structure. We apply pre-stack, time-to-depth migration technique to SS precursors, and move weak underside reflections using PREM-predicted travel-time curves. Common Mid-point gathers are formed to investigate structure under the western Pacific, south America, and Mediterranean convergent boundaries. In general, mantle reflectivity structures are consistent with previous seismic tomography models. In regions of slab penetration (e.g., southern Kurile arc, Aegean Sea), our results show 1) a substantial decrease in S660S amplitude, and 2) strong lower mantle reflector(s) at ~ 900 km depth. These reflective structures are supported by zones of high P and S velocities extending into the lower mantle. Our 1-D synthetic simulations suggest that the decreasing S660S amplitudes are, at least partially, associated with shear wave defocusing due to changes in reflector depth (by ±20 km) within averaging bin. Assuming a ~500 km wide averaging area, a dipping reflector with 6-8 % slope can reduce the amplitude of a SS precursor by ~50%. On the other hand, broad depressions with strong impedance contrast at the base of the MTZ characterize the regions of slab stagnation, such as beneath the Tyrrhenian Sea and northeastern China. For the latter region, substantial topography on the 660-km discontinuity west of the Wadati-Benioff zone suggests that the stagnant part of the Pacific plate across Honshu arc is not

Penetration portion shielding structure

International Nuclear Information System (INIS)

Hayashi, Katsumi; Narita, Hitoshi; Handa, Hiroyuki; Takeuchi, Jun; Tozuka, Fumio.

1994-01-01

Openings of a plurality of shieldings for penetration members are aligned to each other, and penetration members are inserted from the openings. Then, the openings of the plurality of shielding members are slightly displaced with each other to make the penetration portions into a helical configuration, so that leakage of radiation is reduced. Upon removal of the members, reverse operation is conducted. When a flowable shielding material is used, the penetration portions are constituted with two plates having previously formed openings and pipes for connecting the openings with each other and a vessel covering the entire of them. After passing the penetration members such as a cable, the relative position of the two plates is changed by twisting, to form a helical configuration which reduces radiation leakage. Since they are bent into the helical configuration, shielding performance is extremely improved compared with a case that radiation leakage is caused from an opening of a straight pipe. In addition, since they can be returned to straight pipes, attachment, detachment and maintenance can be conducted easily. (N.H.)

Structural and magnetic properties of Co films on highly textured and randomly oriented C_6_0 layers

International Nuclear Information System (INIS)

Kim, Dong-Ok; Choi, Jun Woo; Lee, Dong Ryeol

2016-01-01

The structural and magnetic properties of Co/C_6_0/pentacene and Co/C_6_0 thin film structures were investigated. Atomic force microscopy and x-ray reflectivity analysis show that the presence or absence of a pentacene buffer layer leads to a highly textured or randomly oriented C_6_0 layer, respectively. A Co film deposited on a randomly oriented C_6_0 layer penetrates into the C_6_0 layer when it is deposited at a slow deposition rate. The Co penetration can be minimized, regardless of the Co deposition rate, by growth on a highly textured and nanostructured C_6_0/pentacene layer. Vibrating sample magnetometry measurements show that the saturation magnetization of Co/C_6_0/pentacene is significantly reduced compared to that of Co/C_6_0. On the other hand, the Co penetration does not seem to have an effect on the magnetic properties, suggesting that the structural properties of the Co and C_6_0 layer, rather than the Co penetration into the organic C_6_0 layer, are critical to the magnetic properties of the Co/C_6_0. - Highlights: • Structural and magnetic properties of metal(Co)-organic(C_6_0) interface is studied. • Highly textured C_6_0 layer was grown on a pentacene buffer layer (C_6_0/pentacene). • Co penetration into the C_6_0 is significantly suppressed in Co/C_6_0/pentacene. • The Co magnetization in Co/C_6_0/pentacene is reduced than that in Co/C_6_0.

Structural and magnetic properties of Co films on highly textured and randomly oriented C{sub 60} layers

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong-Ok [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Choi, Jun Woo, E-mail: junwoo@kist.re.kr [Center for Spintronics Research, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Lee, Dong Ryeol, E-mail: drlee@ssu.ac.kr [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of)

2016-03-01

The structural and magnetic properties of Co/C{sub 60}/pentacene and Co/C{sub 60} thin film structures were investigated. Atomic force microscopy and x-ray reflectivity analysis show that the presence or absence of a pentacene buffer layer leads to a highly textured or randomly oriented C{sub 60} layer, respectively. A Co film deposited on a randomly oriented C{sub 60} layer penetrates into the C{sub 60} layer when it is deposited at a slow deposition rate. The Co penetration can be minimized, regardless of the Co deposition rate, by growth on a highly textured and nanostructured C{sub 60}/pentacene layer. Vibrating sample magnetometry measurements show that the saturation magnetization of Co/C{sub 60}/pentacene is significantly reduced compared to that of Co/C{sub 60}. On the other hand, the Co penetration does not seem to have an effect on the magnetic properties, suggesting that the structural properties of the Co and C{sub 60} layer, rather than the Co penetration into the organic C{sub 60} layer, are critical to the magnetic properties of the Co/C{sub 60}. - Highlights: • Structural and magnetic properties of metal(Co)-organic(C{sub 60}) interface is studied. • Highly textured C{sub 60} layer was grown on a pentacene buffer layer (C{sub 60}/pentacene). • Co penetration into the C{sub 60} is significantly suppressed in Co/C{sub 60}/pentacene. • The Co magnetization in Co/C{sub 60}/pentacene is reduced than that in Co/C{sub 60}.

Dielectric properties estimation of the lunar regolith at CE-3 landing site using lunar penetrating radar data

Science.gov (United States)

Feng, Jianqing; Su, Yan; Ding, Chunyu; Xing, Shuguo; Dai, Shun; Zou, Yongliao

2017-03-01

The second channel (CH2) of the Lunar Penetrating Radar (LPR) carried on the Chang'e-3 (CE-3) Yutu Rover was used to determine the thickness and structure of the lunar regolith. Accurately revealing the true structure beneath the surface requires knowledge of the dielectric permittivity of the regolith, which allows one to properly apply migration to the radar image. In contrast to simple assumptions in previous studies, this paper takes account of heterogeneity of the regolith and derives regolith's permittivity distribution laterally and vertically by a method widely used in data processing of terrestrial Ground Penetrating Radar (GPR). We find that regolith permittivity at the landing site increases with depth more quickly than previously recognized. At a depth of ∼2.5-3 m, the dielectric constant reaches the value of solid basalt. The radar image was migrated on the basis of the permittivity profile. We do not find any continuous distinct layers or an apparent regolith/rock interface in the migrated radargram, which implies that this area is covered by relatively young, poorly layered deposits.

Vortex dynamics in ferromagnetic/superconducting bilayers

Energy Technology Data Exchange (ETDEWEB)

Cieplak, M.Z.; Adamus, Z. [Polish Acad Sci, Inst Phys, PL-02668 Warsaw, (Poland); Konczykowski, M. [CEA, DSM, DRECAM, Lab Solides Irradies, Ecole Polytechnique, CNRS-UMR 7642, F-91128 Palaiseau (France); Zhu, L.Y.; Chien, C.L. [Johns Hopkins Univ, Dept Phys and Astron, Baltimore, MD 21218 (United States)

2008-07-01

The dependence of vortex dynamics on the geometry of magnetic domain pattern is studied in the superconducting/ferromagnetic bilayers, in which niobium is a superconductor, and Co/Pt multilayer with perpendicular magnetic anisotropy serves as a ferromagnetic layer. Magnetic domain patterns with different density of domains per surface area and different domain size, w, are obtained for Co/Pt with different thickness of Pt. The dense patterns of domains with the size comparable to the magnetic penetration depth (w {>=} {lambda}) produce large vortex pinning and smooth vortex penetration, while less dense patterns with larger domains (w {>=}{>=} {lambda}) enhance pinning less effectively and result in flux jumps during flux motion. (authors)

In-place HEPA filter penetration test

Energy Technology Data Exchange (ETDEWEB)

Bergman, W.; Wilson, K.; Elliott, J. [Lawrence Livermore National Lab., CA (United States)] [and others

1997-08-01

We have demonstrated the feasibility of conducting penetration tests on high efficiency particulate air (HEPA) filters as installed in nuclear ventilation systems. The in-place penetration test, which is designed to yield equivalent penetration measurements as the standard DOP efficiency test, is based on measuring the aerosol penetration of the filter installation as a function of particle size using a portable laser particle counter. This in-place penetration test is compared to the current in-place leak test using light scattering photometers for single HEPA filter installations and for HEPA filter plenums using the shroud method. Test results show the in-place penetration test is more sensitive than the in-place leak test, has a similar operating procedure, but takes longer to conduct. Additional tests are required to confirm that the in-place penetration test yields identical results as the standard dioctyl phthalate (DOP) penetration test for HEPA filters with controlled leaks in the filter and gasket and duct by-pass leaks. Further development of the procedure is also required to reduce the test time before the in-place penetration test is practical. 14 refs., 14 figs., 3 tabs.

Density scaling on n  =  1 error field penetration in ohmically heated discharges in EAST

Science.gov (United States)

Wang, Hui-Hui; Sun, You-Wen; Shi, Tong-Hui; Zang, Qing; Liu, Yue-Qiang; Yang, Xu; Gu, Shuai; He, Kai-Yang; Gu, Xiang; Qian, Jin-Ping; Shen, Biao; Luo, Zheng-Ping; Chu, Nan; Jia, Man-Ni; Sheng, Zhi-Cai; Liu, Hai-Qing; Gong, Xian-Zu; Wan, Bao-Nian; Contributors, EAST

2018-05-01

Density scaling of error field penetration in EAST is investigated with different n  =  1 magnetic perturbation coil configurations in ohmically heated discharges. The density scalings of error field penetration thresholds under two magnetic perturbation spectra are br\\propto n_e0.5 and br\\propto n_e0.6 , where b r is the error field and n e is the line averaged electron density. One difficulty in understanding the density scaling is that key parameters other than density in determining the field penetration process may also be changed when the plasma density changes. Therefore, they should be determined from experiments. The estimated theoretical analysis (br\\propto n_e0.54 in lower density region and br\\propto n_e0.40 in higher density region), using the density dependence of viscosity diffusion time, electron temperature and mode frequency measured from the experiments, is consistent with the observed scaling. One of the key points to reproduce the observed scaling in EAST is that the viscosity diffusion time estimated from energy confinement time is almost constant. It means that the plasma confinement lies in saturation ohmic confinement regime rather than the linear Neo-Alcator regime causing weak density dependence in the previous theoretical studies.

Unusually Deep Bonin Earthquake (M7.9) of May 30, 2015 Suggests that Stagnant Slab Transforms into Penetration Stage

Science.gov (United States)

Obayashi, M.; Fukao, Y.; Yoshimitsu, J.

2015-12-01

A great shock occurred at an unusual depth of 678 km far away from the well-defined Wadati-Benioff zone of the Izu-Bonin arc (Fig.1). To the north of this region the slab is stagnant above the 660 km discontinuity and to the south it penetrates the discontinuity (Fig.2). Thus, the slab in this region can be viewed as in a transitional state from the stagnant to penetrating slab. Here, the steeply dipping part of the slab bends sharply to horizontal and the great shock happened at the lowest corner of this bending. The CMT indicates a pure normal faulting with the trench-normal near horizontal tensional axis and the near vertical compressional axis (Fig.1). We suggest that this mechanism reflects a transitional state of slab deformation from the bending-dominant mode to the penetration-dominant mode. The mechanism is consistent with either of these two two modes. We show that the mechanism is also consistent with the resultant stress field generated by many deep shocks occurring along the Wadati-Benioff zone. The calculated stress field changes rapidly along a trench-normal profile at a depth of 680 km and becomes similar to that generated by the great shock at points near the hypocenter (Fig.3). Thus, the stress field due to the Wadati-Benioff zone earthquakes works to enhance the occurrence of deep shocks of the type of the 2015 great shock, which represents slab deformation associated with the transition from stagnant to penetrating slab.

Magneto-optical imaging of magnetic flux distribution in high-Tc superconductors

International Nuclear Information System (INIS)

Ueno, K.; Murakamia, H.; Kawayama, I.; Doda, Y.; Tonouchi, M.; Chikumoto, N.

2004-01-01

Prototype systems of home-made magneto-optical microscopes were fabricated, and preliminary studies were carried out using Bi 2 Sr 2 CaCu 2 O 8+δ single crystals and an YBa 2 Cu 3 O 7-δ superconductor vortex flow transistor. In the study using BSCCO crystals, we succeeded in the observation of magnetic flux penetration into half-peeled thin flake region on the crystal surface, and it was found that the magnetic fluxes penetrate in characteristic one-dimensional alignment almost along the crystal a-axis. On the other hand, in the study using the YBCO device clear changes in the generated magnetic field distribution could be detected corresponding to the current direction

Screening Effect of Plasma Flow on RMP Penetration in EXTRAP T2R

Science.gov (United States)

Frassinetti, Lorenzo; Olofsson, Erik; Brunsell, Per; Menmuir, Sheena; Drake, James

2011-10-01

The penetration of resonant magnetic perturbations (RMP) can be screened by plasma flow and the understanding of this phenomenon is important for ELM mitigation techniques. This work studies the screening effect in EXTRAP T2R. EXTRAP T2R is equipped with a feedback system able to suppress all error fields and to produce one or more external perturbations in a controlled fashion. The EXTRAP T2R feedback system is used to generate a RMP that interacts with the dynamics of its corresponding tearing mode (TM). The level of RMP penetration is quantified by analyzing the RMP effect on the TM amplitude and velocity. To study the screening effect, the flow is changed by applying a second perturbation that is non resonant (non-RMP). This produces the flow reduction without perturbing significantly the other parameters. By modifying the amplitude of the non-RMP, an experimental study of the flow effect on the RMP penetration is performed. Experimental results are compared with the model described in [Fitzpatrick R et al., Phys. Plasmas 8, 4489 (2001)].

Performance of carbon fiber reinforced rubber composite armour against shaped charge jet penetration

OpenAIRE

Yue Lian-yong; Li Wei; Zu Xu-dong; Huang Zheng-xiang; Gao Zhen-yu

2016-01-01

Natural rubber is reinforced with carbon fiber; the protective performances of the carbonfiber reinforced rubber composite armour to shaped charge jet have been studied based on the depth of penetration experiments. The craters on the witness blocks, the nature rubber based composite plates’ deformation and the Scanning Electron Microscopy for the hybrid fiber reinforced rubber plate also is analyzed. The results showed that the composite armour can affect the stability of the jet and made pa...

Depth to the bottom of magnetic sources (DBMS) from aeromagnetic data of Central India using modified centroid method for fractal distribution of sources

Science.gov (United States)

Bansal, A. R.; Anand, S. P.; Rajaram, Mita; Rao, V. K.; Dimri, V. P.

2013-09-01

The depth to the bottom of the magnetic sources (DBMS) has been estimated from the aeromagnetic data of Central India. The conventional centroid method of DBMS estimation assumes random uniform uncorrelated distribution of sources and to overcome this limitation a modified centroid method based on scaling distribution has been proposed. Shallower values of the DBMS are found for the south western region. The DBMS values are found as low as 22 km in the south west Deccan trap covered regions and as deep as 43 km in the Chhattisgarh Basin. In most of the places DBMS are much shallower than the Moho depth, earlier found from the seismic study and may be representing the thermal/compositional/petrological boundaries. The large variation in the DBMS indicates the complex nature of the Indian crust.

[Professor WU Zhongchao's experience of penetration needling].

Science.gov (United States)

Zhang, Ning; Wang, Bing; Zhou, Yu

2016-08-12

Professor WU Zhongchao has unique application of penetration needling in clinical treatment. Professor WU applies penetration needling along meridians, and the methods of penetration needling include self-meridian penetration, exterior-interior meridian penetration, identical-name meridian penetration, different meridian penetration. The meridian differentiation is performed according to different TCM syndromes, locations and natures of diseases and acupoint nature, so as to make a comprehensive assessment. The qi movement during acupuncture is focused. In addition, attention is paid on anatomy and long-needle penetration; the sequence and direction of acupuncture is essential, and the reinforcing and reducing methods have great originality, presented with holding, waiting, pressing and vibrating. Based on classical acupoint, the acupoint of penetration needling is flexible, forming unique combination of acupoints.

Giant magnetoimpedance and high frequency electrical detection of magnetic transition in La{sub 0.75}Sr{sub 0.25}MnO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Barik, S K; Rebello, A; Tan, C L; Mahendiran, R [Department of Physics, Faculty of Science, National University of Singapore 2 Science Drive 3, Singapore-117542 (Singapore)

2008-01-21

We show that high frequency electrical transport is an efficient technique for detecting the magnetic transition hidden by the scattering of charges at grain boundaries in colossal magnetoresistive oxides, even in the absence of any external magnetic field. The dc resistivity which shows only a weak anomaly at the Curie temperature in La{sub 0.75}Sr{sub 0.25} MnO{sub 3} transforms into abrupt jumps in both resistive (Z') and reactive (Z-prime) parts of the ac impedance, Z(f, T, H) = Z'(f, T, H) + jZ-prime(f, T, H) at higher frequencies (f = 0.1-5 MHz). The anomaly in Z' and Z-prime at T{sub C} decreases as much as 19% and 15%, respectively, in a dc magnetic field of H 65 mT compared with 1% dc magnetoresistance, suggesting a possible giant low-field magnetoimpedance effect which could be exploited for room temperature practical applications. We interpret our observations due to changes in the magnetic penetration depth induced by the spontaneous ordering of spins and by the applied field. (fast track communication)

Transcranial Magnetic Stimulation-coil design with improved focality

Science.gov (United States)

Rastogi, P.; Lee, E. G.; Hadimani, R. L.; Jiles, D. C.

2017-05-01

Transcranial Magnetic Stimulation (TMS) is a technique for neuromodulation that can be used as a non-invasive therapy for various neurological disorders. In TMS, a time varying magnetic field generated from an electromagnetic coil placed on the scalp is used to induce an electric field inside the brain. TMS coil geometry plays an important role in determining the focality and depth of penetration of the induced electric field responsible for stimulation. Clinicians and basic scientists are interested in stimulating a localized area of the brain, while minimizing the stimulation of surrounding neural networks. In this paper, a novel coil has been proposed, namely Quadruple Butterfly Coil (QBC) with an improved focality over the commercial Figure-8 coil. Finite element simulations were conducted with both the QBC and the conventional Figure-8 coil. The two coil's stimulation profiles were assessed with 50 anatomically realistic MRI derived head models. The coils were positioned on the vertex and the scalp over the dorsolateral prefrontal cortex to stimulate the brain. Computer modeling of the coils has been done to determine the parameters of interest-volume of stimulation, maximum electric field, location of maximum electric field and area of stimulation across all 50 head models for both coils.

X-ray beam penetration in TXRF measurement of polycrystalline and amorphous surfaces

International Nuclear Information System (INIS)

Ghatak-Roy, A.R.; Hossain, T.Z.

2000-01-01

For TXRF measurement on single crystal silicon surface, it is generally agreed that the x-ray beam penetration is of the order of a few hundred Angstroms from the surface. However, for polycrystalline and amorphous surfaces - frequently used in semiconductor manufacturing there are evidences that x-rays penetrate much deeper revealing underlying layers. The evidences come from various measurements done with films such as silicon dioxide, silicon nitride and metal films such as aluminum, titanium and cobalt. A systematic study was carried out to help understand the issue further. Four sets of samples (on 8 inch wafers) were prepared to create layers buried under various deposited metal and non-metal layers. The metal layers created were aluminum, titanium and cobalt and the non-metal layers were silicon dioxide and silicon nitride. These samples were analyzed by TXRF under various angles and energies and the data were analyzed for signals from various buried layers along with their angular dependence. The results indicated deep penetration of x-ray beams. The samples were further analyzed by SIMS (Secondary Ion Mass Spectrometry) and some of them by ICP-MS (Inductively Coupled Plasma - Mass Spectrometry) to obtain information about their depth profiles. This was done in order to rule out the possibility of intermixing of layers during deposition. (author)

Effect of Heat Input During Disk Laser Bead-On-Plate Welding of Thermomechanically Rolled Steel on Penetration Characteristics and Porosity Formation in the Weld Metal

Directory of Open Access Journals (Sweden)

Lisiecki A.

2016-03-01

Full Text Available The paper presents a detailed analysis of the influence of heat input during laser bead-on-plate welding of 5.0 mm thick plates of S700MC steel by modern Disk laser on the mechanism of steel penetration, shape and depth of penetration, and also on tendency to weld porosity formation. Based on the investigations performed in a wide range of laser welding parameters the relationship between laser power and welding speed, thus heat input, required for full penetration was determined. Additionally the relationship between the laser welding parameters and weld quality was determined.

Metasploit penetration testing cookbook

CERN Document Server

Agarwal, Monika

2013-01-01

This book follows a Cookbook style with recipes explaining the steps for penetration testing with WLAN, VOIP, and even cloud computing. There is plenty of code and commands used to make your learning curve easy and quick.This book targets both professional penetration testers as well as new users of Metasploit, who wish to gain expertise over the framework and learn an additional skill of penetration testing, not limited to a particular OS. The book requires basic knowledge of scanning, exploitation, and the Ruby language.

Penetration Experiments with 6061-T6511 Aluminum Targets and Spherical-Nose Steel Projectiles at Striking Velocities Between 0.5 and 3.0 km/s

Energy Technology Data Exchange (ETDEWEB)

Forrestal, M.J.; Piekutowski, A.J.

1999-02-04

We conducted depth of penetration experiments with 7.11-mm-diameter, 74.7-mm-long, spherical-nose, 4340 steel projectiles launched into 250-mm-diameter, 6061-T6511 aluminum targets. To show the effect of projectile strength, we used projectiles that had average Rockwell harnesses of R{sub c} = 36.6, 39.5, and 46.2. A powder gun and two-stage, light-gas guns launched the 0.023 kg projectiles at striking velocities between 0.5 and 3.0 km/s. Post-test radiographs of the targets showed three response regions as striking velocities increased: (1) the projectiles remained visibly undeformed, (2) the projectiles permanently deformed without erosion, and (3) the projectiles eroded and lost mass. To show the effect of projectile strength, we compared depth-of-penetration data as a function of striking velocity for spherical-nose rods with three Rockwell harnesses at striking velocities ranging from 0.5 to 3.0 km/s. To show the effect of nose shape, we compared penetration data for the spherical-nose projectiles with previously published data for ogive-nose projectiles.

High Penetration Solar PV Deployment Sunshine State Solar Grid Initiative (SUNGRIN)

Energy Technology Data Exchange (ETDEWEB)

Meeker, Rick [Nhu Energy, Inc., Tallahassee, FL (United States); Florida State Univ., Tallahassee, FL (United States); Steurer, Mischa [Florida State Univ., Tallahassee, FL (United States); Faruque, MD Omar [Florida State Univ., Tallahassee, FL (United States); Langston, James [Florida State Univ., Tallahassee, FL (United States); Schoder, Karl [Florida State Univ., Tallahassee, FL (United States); Ravindra, Harsha [Florida State Univ., Tallahassee, FL (United States); Hariri, Ali [Florida State Univ., Tallahassee, FL (United States); Moaveni, Houtan [New York Power Authority (NYPA), New York (United States); University of Central Florida, Florida Solar Energy Center, Cocoa, FL (Unitied States); Click, Dave [ESA Renewables, LLC, Sanford, FL (United States); University of Central Florida, Florida Solar Energy Center, Cocoa, FL (United States); Reedy, Bob [University of Central Florida, Florida Solar Energy Center, Cocoa, FL (United States)

2015-05-31

The report provides results from the Sunshine State Solar Grid Initiative (SUNGRIN) high penetration solar PV deployment project led by Florida State University’s (FSU) Center for Advanced Power Systems (CAPS). FSU CAPS and industry and university partners have completed a five-year effort aimed at enabling effective integration of high penetration levels of grid-connected solar PV generation. SUNGRIN has made significant contributions in the development of simulation-assisted techniques, tools, insight and understanding associated with solar PV effects on electric power system (EPS) operation and the evaluation of mitigation options for maintaining reliable operation. An important element of the project was the partnership and participation of six major Florida utilities and the Florida Reliability Coordinating Council (FRCC). Utilities provided details and data associated with actual distribution circuits having high-penetration PV to use as case studies. The project also conducted foundational work supporting future investigations of effects at the transmission / bulk power system level. In the final phase of the project, four open-use models with built-in case studies were developed and released, along with synthetic solar PV data sets, and tools and techniques for model reduction and in-depth parametric studies of solar PV impact on distribution circuits. Along with models and data, at least 70 supporting MATLAB functions have been developed and made available, with complete documentation.

A Mass Loss Penetration Model to Investigate the Dynamic Response of a Projectile Penetrating Concrete considering Mass Abrasion

Directory of Open Access Journals (Sweden)

NianSong Zhang

2015-01-01

Full Text Available A study on the dynamic response of a projectile penetrating concrete is conducted. The evolutional process of projectile mass loss and the effect of mass loss on penetration resistance are investigated using theoretical methods. A projectile penetration model considering projectile mass loss is established in three stages, namely, cratering phase, mass loss penetration phase, and remainder rigid projectile penetration phase.

The oxygen-isotope effect on the in-plane penetration depth in underdoped Y{sub 1-x} Pr{sub x} Ba{sub 2} Cu{sub 3} O{sub 7-{delta}} as revealed by muon-spin rotation

Energy Technology Data Exchange (ETDEWEB)

Khasanov, R [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland); Shengelaya, A [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland); Conder, K [Laboratory for Neutron Scattering, ETH Zuerich and PSI Villigen, CH-5232 Villigen PSI (Switzerland); Morenzoni, E [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Savic, I M [Faculty of Physics, University of Belgrade, 11001 Belgrade (Yugoslavia); Keller, H [Physik-Institut der Universitaet Zuerich, CH-8057 Zurich (Switzerland)

2003-01-22

The oxygen-isotope ({sup 16}O/{sup 18}O) effect (OIE) on the in-plane penetration depth {lambda}{sub ab} (0) in underdoped Y{sub 1-x} Pr{sub x} Ba{sub 2} Cu{sub 3} O{sub 7-{delta}} was studied by means of muon-spin rotation. A pronounced OIE on {lambda}{sub ab}{sup -2} (0) was observed with a relative isotope shift of {delta}{lambda}{sub ab}{sup -2} /{lambda} {sub ab}{sup -2} = -5(2)% for x=0.3 and -9(2)% for x=0.4. The OIE exponents of T{sub c} and of {lambda}{sub ab}{sup -2} (0) exhibit a relation that appears to be generic for cuprate superconductors. (letter to the editor)

Detection of discretized single-shell penetration in mesoscopic vortex matter

International Nuclear Information System (INIS)

Dolz, M I; Fasano, Y; Bolecek, N R Cejas; Pastoriza, H; Konczykowski, M; Beek, C J van der

2014-01-01

We investigated configurational changes in mesoscopic vortex matter with less than thousand vortices during flux penetration in freestanding 50 μm diameter disks of Bi 2 Sr 2 CaCu 2 O 8+δ . High-resolution AC and DC local magnetometry data reveal oscillations in the transmittivity echoed in peaks in the third-harmonics magnetic signal fainting on increasing vortex density. By means of extra experimental evidence and a simple geometrical analysis we show that these features fingerprint the discretized entrance of single-shells of vortices having a shape that mimics the sample edge

Tritium depth profiling in carbon by accelerator mass spectrometry