Journal articles: 'Current-free double layer'

1

Maciel, Homero Santiago, and J. E. Allen. "Free double layers in mercury-arc discharges." Journal of Plasma Physics 42, no. 2 (October 1989): 321–52. http://dx.doi.org/10.1017/s0022377800014380.

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A study has been carried out of free double layers formed within the plasma volume of a low-pressure mercury-arc discharge at high current densities. The free double layer is observed to form as a visible boundary, which drifts slowly from the central section of the discharge. Current-driven instabilities are observed as the discharge current is gradually increased to a critical value, at which current limitation is observed to occur. This process, which is accompanied by high-current spikes, ceases when the free double layer becomes visible as a sharp boundary dividing the discharge column into two regions of different luminosities. The layer is observed to form in the later stages of current limitation, the onset of which occurs for a ratio of drift to thermal speed of electrons of about unity. Electrical energy is converted by the layer into kinetic energy of the charged particles. Accordingly, high-energy ions were measured by means of an electrostatic energy analyser. The multiple-sheath character of the free ‘double layer’, which is inferred from probe measurements of potential profiles, is discussed and comparisons with other space-charge structures with the same topology are made.

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2

Charles, C., and R. W. Boswell. "Time development of a current-free double-layer." Physics of Plasmas 11, no. 8 (August 2004): 3808–12. http://dx.doi.org/10.1063/1.1764829.

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Baalrud, S. D., T. Lafleur, R. W. Boswell, and C. Charles. "Particle-in-cell simulations of a current-free double layer." Physics of Plasmas 18, no. 6 (June 2011): 063502. http://dx.doi.org/10.1063/1.3594565.

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Hairapetian, G., and R. L. Stenzel. "Observation of a stationary, current-free double layer in a plasma." Physical Review Letters 65, no. 2 (July 9, 1990): 175–78. http://dx.doi.org/10.1103/physrevlett.65.175.

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Keesee, Amy M., Earl E. Scime, Christine Charles, Albert Meige, and Rod Boswell. "The ion velocity distribution function in a current-free double layer." Physics of Plasmas 12, no. 9 (September 2005): 093502. http://dx.doi.org/10.1063/1.2033647.

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Boswell, Roderick W., Eckart Marsch, and Christine Charles. "The Current-Free Electric Double Layer in a Coronal Magnetic Funnel." Astrophysical Journal 640, no. 2 (March 7, 2006): L199—L202. http://dx.doi.org/10.1086/503155.

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Ganguli, A., B. B. Sahu, and R. D. Tarey. "Evidence of current free double layer in high density helicon discharge." Physics of Plasmas 20, no. 1 (January 2013): 013510. http://dx.doi.org/10.1063/1.4789455.

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8

Charles, C. "High source potential upstream of a current-free electric double layer." Physics of Plasmas 12, no. 4 (April 2005): 044508. http://dx.doi.org/10.1063/1.1883182.

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Charles, Christine, and Rod Boswell. "Current-free double-layer formation in a high-density helicon discharge." Applied Physics Letters 82, no. 9 (March 3, 2003): 1356–58. http://dx.doi.org/10.1063/1.1557319.

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10

Lieberman, M. A., C. Charles, and R. W. Boswell. "A theory for formation of a low pressure, current-free double layer." Journal of Physics D: Applied Physics 39, no. 15 (July 21, 2006): 3294–304. http://dx.doi.org/10.1088/0022-3727/39/15/011.

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11

Takahashi, K., C. Charles, R. W. Boswell, T. Kaneko, and R. Hatakeyama. "Measurement of the energy distribution of trapped and free electrons in a current-free double layer." Physics of Plasmas 14, no. 11 (November 2007): 114503. http://dx.doi.org/10.1063/1.2803763.

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12

Takahashi, Kazunori, Christine Charles, Rod Boswell, Michael A. Lieberman, and Rikizo Hatakeyama. "Characterization of the temperature of free electrons diffusing from a magnetically expanding current-free double layer plasma." Journal of Physics D: Applied Physics 43, no. 16 (April 8, 2010): 162001. http://dx.doi.org/10.1088/0022-3727/43/16/162001.

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13

Sato, Kunihiro, and Fujio Miyawaki. "Formation of presheath and current‐free double layer in a two‐electron‐temperature plasma." Physics of Fluids B: Plasma Physics 4, no. 5 (May 1992): 1247–54. http://dx.doi.org/10.1063/1.860080.

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Charles, C. "Hydrogen ion beam generated by a current-free double layer in a helicon plasma." Applied Physics Letters 84, no. 3 (January 19, 2004): 332–34. http://dx.doi.org/10.1063/1.1643548.

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15

Meige, A., R. W. Boswell, C. Charles, J. P. Boeuf, G. Hagelaar, and M. M. Turner. "One-dimensional simulation of an ion beam generated by a current-free double-Layer." IEEE Transactions on Plasma Science 33, no. 2 (April 2005): 334–35. http://dx.doi.org/10.1109/tps.2005.844956.

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Charles, C., and R. W. Boswell. "Laboratory evidence of a supersonic ion beam generated by a current-free “helicon” double-layer." Physics of Plasmas 11, no. 4 (April 2004): 1706–14. http://dx.doi.org/10.1063/1.1652058.

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Meige, Albert, Rod W. Boswell, Christine Charles, and Miles M. Turner. "One-dimensional particle-in-cell simulation of a current-free double layer in an expanding plasma." Physics of Plasmas 12, no. 5 (May 2005): 052317. http://dx.doi.org/10.1063/1.1897390.

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Aswad, Ammar J., Nadeem K. Hassan, and Adnan R. Ahmed. "Simulation and Numerical Modelling of CIGSSe-Based Solar Cells by AFORS-HET." Journal of Physics: Conference Series 2114, no. 1 (December 1, 2021): 012075. http://dx.doi.org/10.1088/1742-6596/2114/1/012075.

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Abstract A general equation to determine properties of penternary solar cell based on Cu (In, Ga) (Se, S) 2 (CIGSSe) with a double buffer layer ZnS/Zn0.8Mg0.2O(ZMO) were derived. Numerical analysis of a (CIGSSe) solar cell with a double buffer layer ZnS/ZMO, CdS free absorber layer, were investigated using the AFORS-HET software simulation. Taking into consideration the effect of thickness and doping concentration for the CIGSSe absorption layer, ZnS buffer layer and ZnO:B(BZO) window layer on the electron transport, short circuit current density (Jsc) and open circuit voltage (Voc); numerical simulation demonstrated that the changes in band structure characteristics occurred. The solar energy conversion efficiency is 28.34%, the filling factor is 85.59%, the open circuit voltage is 782.3 mV, the short circuit current is 42.32 mA. then we take the range of the gradient between the ratio of x and y for the absorption layer, and the best result of Voc, Jsc, FF, Eff equal (838.7 mV, 40.94 mA/cm2, 86.23%, 29.61%) respectively at x= 0, y= 0.26.

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WALKER, DAVID T. "On the origin of the ‘surface current’ in turbulent free-surface flows." Journal of Fluid Mechanics 339 (May 25, 1997): 275–85. http://dx.doi.org/10.1017/s0022112097005181.

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In this study, the interaction with a free surface of an initially axisymmetric jet issuing beneath and parallel to the surface was examined. The purpose was to determine the origin of the ‘surface current’ – the large outward velocity which exists in a thin layer adjacent to the surface. Using the equations of mean motion, it is shown that near the surface, outward acceleration results from the balance between a positive contribution from the lateral Reynolds-stress gradients and a negative contribution from the lateral pressure gradient. The local pressure field near the free surface is shown to be largely determined by the local Reynolds-stress field. Combining these results shows that the lateral acceleration which results in the surface current is related to the Reynolds-stress anisotropy near the surface. The results indicate that there should be roughly a three-fold increase in the lateral growth rate of the jet near the free surface and a similar increase in the outward velocity, when compared to a deep jet. Comparison to available experimental data showed that the maximum outward velocity was consistent with the theory, and that the lateral scale of the surface-current layer was roughly double that of the deep jet, slightly smaller than expected. The near-surface stress anisotropy was shown to be related to the interaction of vorticity with the free surface. This indicates that the results of this study are consistent with earlier explanations of the surface current in terms of vortex/free-surface interaction.

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Stenzel, Reiner L., Johannes Grünwald, Codrina Ionita, Roman Schrittwieser, and Manuel Urrutia. "Sheaths and Double Layers with Instabilities." Journal of Technological and Space Plasmas 2, no. 1 (March 24, 2021): 70–92. http://dx.doi.org/10.31281/jtsp.v2i1.16.

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The properties of sheaths and associated potential structures and instabilities cover a broad field which even a review cannot cover everything. Thus, the focus will be on about a dozen examples, describe their observations and focus on the basic physical explanations for the effects, while further details are found in the references. Due to familiarity the review focuses mainly on the authors work but compared and referenced related work. The topics start with a high frequency oscillations near the electron plasma frequency. Low frequency instabilities also occur at the ion plasma frequency.The injection of ions into an electron-rich sheath widens the sheath and forms a double layer. Likewise, the injection of electrons into an ion rich sheath widens and establishes a double layer which occurs in free plasma injection into vacuum. The sheath widens and forms a double layer by ionization in an electron rich sheath. When particle fluxes in "fireballs" gets out of balance the double layer performs relaxation instabilities which has been studied extensively. Fireballs inside spherical electrodes create a new instability due to the transit time of trapped electrons. On cylindrical and spherical electrodes the electron rich sheath rotates in magnetized plasmas. Electrons rotate due to $\mathbf E \times \mathbf B_0$ which excites electron drift waves with azimuthal eigenmodes. Conversely a permanent magnetic dipole has been used as a negative electrode. The impact of energetic ions produces secondary electron emission, forming a ring of plasma around the magnetic equator. Such "magnetrons" are subject to various instabilities. Finally, the current to a positively biased electrode in a uniformly magnetized plasma is unstable to relaxation oscillations, which shows an example of global effects. The sheath at the electrode raises the potential in the flux tube of the electrode thereby creating a radial sheath which moves unmagnetized ions radially. The ion motion creates a density perturbation which affects the electrode current. If the electrode draws large currents the current disruptions create large inductive voltages on the electrode, which again produce double layers. This phenomenon has been seen in reconnection currents. Many examples of sheath properties will be explained. Although the focus is on the physics some examples of applications will be suggested such as neutral gas heating and accelerating, sputtering of plasma magnetrons and rf oscillators.

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21

Sugamata, Kota, Hirofumi Tsuge, Kiyoji Ikeda, Michitaka Yoshino, Kazuo Kuriyama, and Tohru Nakamura. "Lateral GaN MISFETs Fabricated in Mg Ion Implanted Layer." Materials Science Forum 924 (June 2018): 919–22. http://dx.doi.org/10.4028/www.scientific.net/msf.924.919.

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This paper demonstrates ion implanted lateral GaN MISFETs using double ion implantation technology, which enables us to form Si ion implanted source/drain regions in Mg ion implanted p-well fabricated on free-standing GaN substrates. Maximum drain current of 39 mA/mm and maximum transconductance of 4.5 mS/mm for GaN MISFET with a gate length of 2 μm at an estimated Mg surface concentration of 2.2 × 1018cm-3were obtained. A threshold voltage was-0.5 V for the device. These results show that we successfully formed Si ion implanted n-type regions in the Mg ion-implanted layer and achieved innovative performance.

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Omori, Tomoki, Masahiro Nakanishi, and Daisuke Tashima. "High-Temperature Degradation Tests on Electric Double-Layer Capacitors: The Effect of Residual Voltage on Degradation." Materials 14, no. 6 (March 20, 2021): 1520. http://dx.doi.org/10.3390/ma14061520.

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The demand for electric double-layer capacitors, which have high capacity and are maintenance-free, for use in a variety of devices has increased. Nevertheless, it is important to know the degradation behavior of these capacitors at high temperatures because they are expected to be used in severe environments. Therefore, degradation tests at 25 °C and 80 °C were carried out in the current study to analyze the degradation behavior. Steam-activated carbon, Ketjen black, and PTFE were used as the electrodes, conductive material, and binder, respectively, and KOH was used as the electrolyte. The impedance and capacitance were calculated from the voltage and current in the device using the alternating current (AC) impedance method. The results showed that the impedance increased and the capacitance decreased over 14 days at 80 °C, which is the inverse of what we observed at 25 °C. Rapid degradation was also confirmed from the 80 °C degradation test. The residual voltage after measuring the current and voltage was a prominent factor influencing this rapid degradation.

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Lv, Fengzhen, Tingting Zhong, Yongfu Qin, Haijun Qin, Wenfeng Wang, Fuchi Liu, and Wenjie Kong. "Resistive Switching Characteristics Improved by Visible-Light Irradiation in a Cs2AgBiBr6-Based Memory Device." Nanomaterials 11, no. 6 (May 21, 2021): 1361. http://dx.doi.org/10.3390/nano11061361.

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Light-modulated lead-free perovskites-based memristors, combining photoresponse and memory, are promising as multifunctional devices. In this work, lead-free double perovskite Cs2AgBiBr6 films with dense surfaces and uniform grains were prepared by the low-temperature sol-gel method on indium tin oxide (ITO) substrates. A memory device based on a lead-free double perovskite Cs2AgBiBr6 film, Pt/Cs2AgBiBr6/ITO/glass, presents obvious bipolar resistive switching behavior. The ROFF/RON ratio under 445 nm wavelength light illumination is ~100 times greater than that in darkness. A long retention capability (>2400 s) and cycle-to-cycle consistency (>500 times) were observed in this device under light illumination. The resistive switching behavior is primarily attributed to the trap-controlled space-charge-limited current mechanism caused by bromine vacancies in the Cs2AgBiBr6 medium layer. Light modulates resistive states by regulating the condition of photo-generated carriers and changing the Schottky-like barrier of the Pt/Cs2AgBiBr6 interface under bias voltage sweeping.

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Aanesland, A., M. A. Lieberman, C. Charles, and R. W. Boswell. "Experiments and theory of an upstream ionization instability excited by an accelerated electron beam through a current-free double layer." Physics of Plasmas 13, no. 12 (December 2006): 122101. http://dx.doi.org/10.1063/1.2398929.

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Charles, C. "Spatially resolved energy analyzer measurements of an ion beam on the low potential side of a current-free double-layer." IEEE Transactions on Plasma Science 33, no. 2 (April 2005): 336–37. http://dx.doi.org/10.1109/tps.2005.844958.

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Browne, P. F. "Acceleration in the plasma focus and in astrophysics." Laser and Particle Beams 6, no. 3 (August 1988): 409–20. http://dx.doi.org/10.1017/s0263034600005358.

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Both, in the laboratory (specifically the plasma focus) and in astrophysics, charges are accelerated in magnetically pinched current channels. The current channels are annular cylinders, defined by an electric double layer of thickness δrE and radius R due to radial polarization of the plasma. The electric field Er in the double layer and the azimuthal magnetic field Bϕ ensure drifts of charges in the axial direction, but ions do not take up the full drift velocity because their Larmor radius exceeds δrE. Magnetic pinching of the channel reduces the cross sectional area S, and an instability of drift velocity may denude a region of current channel. The inductively maintained current J then cannot be carried by free charges, even with relativistic drift velocity. A displacement current (S/4π) δEz/δt arises, Ez growing until all energy in Bϕ is transferred into Ez. During this transfer Bϕ decreases, so the pinch weakens, permitting discharge of accumulated space charge via a conduction current without reversal of J. Thereafter the cycle repeats quasi-periodically.In astrophysics acceleration occurs in a pinched magnetic vortex tube (MVT). The difference is that now Bϕ(r, +z) = −Bϕ(r, −z) due to winding of loops of field lines. Hence J reverses across mid-pinch, which implies accumulation of space charge of one sign at mid-pinch and of opposite sign at the ends of the pinch. Now there is reversal of J when the space charge relaxes.

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Mohammadi, B., H. Hosseini-Toudeshky, and M.-H. Sadr-Lahidjani. "Free-edge effects analysis of angle-ply laminates under transverse loading using layer-wise finite-element method with semi-analytical shear stress calculation." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, no. 2 (December 1, 2008): 293–306. http://dx.doi.org/10.1243/09544062jmes1063.

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Free-edge stress fields are of an utmost localized nature exhibiting steep stress gradients and they rapidly decay with increasing distance from the laminates’ edges. Layer-wise theory has already been used to analyse the stress field at the free edges of the laminates. In this investigation, the layer-wise theory in finite-element method (FEM) is used to analyse the stress field of the laminates’ free edges. In this study, apart from the conventional FEM in which the stresses are calculated from the constitutive laws, the shear stress components along the thickness are calculated from the equilibrium equations by employing a semi-analytical approach. It is shown that the obtained stresses from the current investigation are very close to those available from the three-dimensional elasticity solution for a square laminate under transversely double sinusoidal pressure distribution. To investigate the free edge influence on shear stress distribution of laminates under transverse loading, the analyses are performed for three angle-ply lay-ups with clustered and alternating sequences. It is shown that the free edge effects of angle-ply laminates with different stacking sequences under transverse pressure loading could be considerably different from laminates with in-plane loading conditions.

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Yang, Wenlong, Hui Zhou, Yonggang Wang, Juan Liu, Hengchang Liu, Chenglong Liu, and William Dewar. "Direct Measurements of Turbulence in the Upper Western Pacific North Equatorial Current over a 25-h Period." Sensors 22, no. 3 (February 3, 2022): 1167. http://dx.doi.org/10.3390/s22031167.

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Measurements of the turbulent kinetic energy dissipation rate (ε) were conducted by a free-fall microstructure profiler in the western Pacific North Equatorial Current (WPNEC) during a continuous period of 25 h, from the sea surface to about 160 m depth. In the mixed layer (ML), ε values were typically on the order of 10−8∼10−7 W kg−1, and an obvious diurnal cycle existed in the upper 40 m of the surface mixing layer. Below the ML, ε was reduced to 10−9∼10−8 W kg−1 with some patches of high ε reaching 10−7.5 W kg−1. The barrier layer was identified in the nighttime with a maximum thickness of 20 m, and it was eroded by the advection of freshwater within the lower part of the isothermal layers associated with an anticyclonic eddy in the afternoon. A simple scaling relevant to shear (S2) instability and stratification (N2) that can predict turbulent dissipation rates in the transition layer, between the well-mixed layer and the thermocline below, was obtained through the scaling ε∼S−0.40N0.20. Besides turbulence, double-diffusive processes also contributed to the vertical mixing levels in the upper WPNEC.

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Angkurarach, L., and P. Juijerm. "Effects of direct current field on powder-packed boriding process on martensitic stainless steel AISI 420." Archives of Metallurgy and Materials 57, no. 3 (October 1, 2012): 799–804. http://dx.doi.org/10.2478/v10172-012-0087-3.

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The effects of direct current field on a powder-packed boriding process on a martensitic stainless steel AISI 420 have been investigated at a temperature of 900°C for about 2–6 hr. A powder-packed boriding process without direct current field (conventional powder-packed boriding process, PB) is a reference as compared to the powder-packed boriding process with applied current densities (PB-DC) of 60-170 mA/cm2. The microstructure and the presence of boride layers of PB and PB-DC were characterized using optical microscope and X-ray diffraction (XRD). The hardness values of the boride layer were measured by Vickers microhardness tester. Experimental results show that the direct current filed can enhance the decomposition and chemical reaction in the boriding agent and also drive active free boron ions as well as atoms to diffuse toward the cathode. Therefore, a boron concentration around the specimen at the cathode of PB-DC is higher than that at the anode as well as PB (as a reference). As a consequence, higher boride layer thickness of PB-DC was detected. The double-phase boride layer (FeB and Fe2B) on borided martensitic stainless steel AISI 420 was found both PB and PB-DC. The hardness of the boride layer of about 1800–2000 HV can be observed.

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Lennartsson, W. "Some aspects of double layer formation in a plasma constrained by a magnetic mirror." Laser and Particle Beams 5, no. 2 (May 1987): 315–24. http://dx.doi.org/10.1017/s0263034600002792.

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The discussion of parallel electric fields in the earth's magnetosphere has undergone a notable shift of emphasis in recent years, away from wave-generated anomalous resistivity towards the more large-scale effects of magnetic confinement of current carrying plasmas. This shift has been inspired in large part by the more extensive data on auroral particle distribution functions that have been made available, data that may often seem consistent with a dissipation-free acceleration of auroral electrons over an extended altitude range.Efforts to interpret these data have brought new vigor to the concept that a smooth and static electric field can be self-consistently generated by suitable pitch-angle anisotropies among the high-altitude particle populations, different for electrons and ions, and that such an electric field is both necessary and sufficient to maintain the plasma in a quasi-neutral steady state. This paper reviews and criticizes certain aspects of this concept, both from a general theoretical standpoint and from the standpoint of what we know about the magnetospheric environment. It is argued that this concept has flaws and that the actual physical problem is considerably more complicated, requiring a more complex electric field, possibly including double layer structures.

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Amadelli, Rossano, Luca Samiolo, and Aleksandr Velichenko. "An electrochemical and radiotracer investigation on lead dioxide: Influence of deposition current and temperature." Journal of the Serbian Chemical Society 78, no. 12 (2013): 2099–114. http://dx.doi.org/10.2298/jsc131022122a.

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The properties of electrodeposited PbO2 are sensibly influenced by deposition current and temperature. In particular, tritium radiotracer measurements have demonstrated that protons are incorporated in the bulk of the oxide film and on its surface. The degree of hydration increases with increasing current and decreases with temperature, and is related to the morphological characteristics of the oxide such as roughness measured by changes of the double layer capacity. Conversely, the amount of hydrogen has negligible effects on the number of free carriers evaluated from Mott-Schottky plots. The hydration degree of the surface seems to be an important factor influencing electrocatalytic processes at high potentials such as O2 evolution and O3 formation. On less hydrated, more crystalline PbO2 surfaces the first process is inhibited, and accordingly, the second is favored.

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Yotsuji, Kenji, Yukio Tachi, and Yuichirou Nishimaki. "Diffusion Modeling in Compacted Bentonite Based on Modified Gouy-Chapman Model." MRS Proceedings 1665 (2014): 123–29. http://dx.doi.org/10.1557/opl.2014.637.

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ABSTRACTThe integrated sorption and diffusion (ISD) model has been developed to quantify radionuclide transport in compacted bentonite. The current ISD model, based on averaged pore aperture and the Gouy-Chapman electric double layer (EDL) theory can quantitatively account for diffusion of monovalent cations and anions under a wide range of conditions (e.g., salinity, bentonite density). To improve the applicability of the current ISD model for multivalent ions and complex species, the excluded volume effect and the dielectric saturation effect were incorporated into the current model, and the modified Poisson-Boltzmann equations were numerically solved. These modified models had little effect on the calculation of effective diffusivity of Sr2+/Cs+/I−. On the other hand, the model, modified considering the effective electric charge of hydrated ions, calculated using the Gibbs free energy of hydration, agreed well with the diffusion data including those of Sr2+.

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Takikawa, Yoshihiro, Koji Kakutani, Yoshinori Matsuda, Teruo Nonomura, Shin-ichi Kusakari, and Hideyoshi Toyoda. "A Promising Physical Pest-Control System Demonstrated in a Greenhouse Equipped With Simple Electrostatic Devices That Excluded All Insect Pests: A Review." Journal of Agricultural Science 11, no. 18 (November 15, 2019): 1. http://dx.doi.org/10.5539/jas.v11n18p1.

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Applied electrostatic engineering can be used to construct greenhouses that prevent entry of insect pests. Two types of electric field screen were used to exclude pests from the greenhouse: single- and double-charged dipolar electric field screens (S- and D-screen, respectively). The S-screen consisted of iron insulated conductor wires (ICWs) arrayed in parallel (ICW-layer), a grounded metal net on either side of the ICW-layer, and a direct current voltage generator. S-screens were attached to the side windows of the greenhouse to repel whiteflies (Bemisia tabaci) that approached the nets. The D-screen was installed in a small anteroom at the greenhouse entrance to capture whiteflies entering through it. The ICW-layers of the D-screen were oppositely charged with equal voltages and arrayed alternately, and an insulator board or grounded metal net was placed on one side of the ICW-layer. The ICW-layers captured whiteflies entering the electric field of the double-charged dipolar electric field. Three screens equipped with yellow or gray boards or a grounded metal net were installed in the anteroom based on the airflow inside the room, as most whiteflies were brought in by air when the door was opened. Two D-screens with boards were useful for directing the airflow toward the wall with the netted D-screen. This screen eliminated the insects and the pest-free air was circulated inside the greenhouse. The D-screen with the yellow board attracted the whiteflies and was effective for trapping them when there was no wind. Our method kept the greenhouse pest-free throughout the entire period of tomato (Solanum lycopersicum) cultivation.

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Wang, Jianxing, Xinyue Liu, Ying Liu, and Guowei Yang. "Active Pore-Edge Engineering of Single-Layer Niobium Diselenide Porous Nanosheets Electrode for Hydrogen Evolution." Nanomaterials 9, no. 5 (May 16, 2019): 751. http://dx.doi.org/10.3390/nano9050751.

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Two-dimensional transition-metal dichalcogenides (TMDs) possess interesting catalytic properties for the electrochemical-assisted hydrogen-evolution reaction (HER). We used niobium diselenide (NbSe2) as a representative TMD, and prepared single-layer NbSe2 porous nanosheets (PNS) by a double-sonication liquid-phase exfoliation, with H2O2 as a pore-forming agent. The single-layer NbSe2 PNS were drop-cast on carbon foam (CF) to fabricate a three-dimensional robust NbSe2 PNS/CF electrode. The NbSe2 PNS/CF electrode exhibits a high current density of −50 mA cm−2 with an overpotential of 148 mV and a Tafel slope of 75.8 eV dec−1 for the HER process. Little deactivation is detected in continuous CV testing up to 20,000 cycles, which suggests that this novel NbSe2 PNS/CF is a promising catalytic electrode in the HER application. The porous structure of single-layer NbSe2 nanosheets can enhance the electrochemical performance compared with that of pore-free NbSe2 nanosheets. These findings illustrate that the single-layer NbSe2 PNS is a potential electrocatalytic material for HER. More importantly, the electrochemical performance of the NbSe2 PNS/CF expands the use of two-dimensional TMDs in electrocatalysis-related fields.

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Zinenko, Tatiana L., Akira Matsushima, and Alexander I. Nosich. "Terahertz range resonances of metasurface formed by double-layer grating of microsize graphene strips inside dielectric slab." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 476, no. 2240 (August 2020): 20200173. http://dx.doi.org/10.1098/rspa.2020.0173.

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We analyse, using integral equations and a previously developed in-house numerical algorithm, the scattering and absorption of the H -polarized plane wave by a metasurface consisting of a double-layer grating of flat graphene strips placed into a lossless dielectric slab. The algorithm is meshless and its convergence is guaranteed mathematically. It is a version of the method of analytical preconditioning; namely, it uses the set of weighted Chebyshev polynomials as expansion functions in the discretization of a hypersingular electric field integral equation for the on-strip current. Then the computational error is controlled by the matrix size and can be reduced to machine precision. Using this advanced tool, we plot the frequency dependences, in a huge range from 1 GHz to 10 THz, of the transmittance, reflectance and absorbance of such a metasurface. This accurate analysis reveals resonances on several types of natural modes, best understood via visualization of in-resonance near-fields. In addition to plasmon-mode resonances, special attention is paid to the ultra-high- Q resonances on the lattice modes, which are absent on the free-standing graphene strip gratings.

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Zatko, Bohumir, Andrea Sagatova, Katarina Sedlackova, Vladimir Necas, Frantisek Dubecky, Michael Solar, and Carlos Granja. "Detection of fast neutrons from D–T nuclear reaction using a 4H–SiC radiation detector." International Journal of Modern Physics: Conference Series 44 (January 2016): 1660235. http://dx.doi.org/10.1142/s2010194516602350.

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The particle detector based on a high purity epitaxial layer of 4H–SiC exhibits promising properties in detection of various types of ionizing radiation. Due to the wide band gap of 4H–SiC semiconductor material, the detector can reliably operate at room and also elevated temperatures. In this work we focused on detection of fast neutrons generated the by D–T (deuterium–tritium) nuclear reaction. The epitaxial layer with a thickness of 105 [Formula: see text]m was used as a detection part. A circular Schottky contact of a Au/Ni double layer was evaporated on both sides of the detector material. The detector structure was characterized by current-voltage and capacitance-voltage measurements, at first. The results show very low current density (<0.1 nA/cm[Formula: see text] at room temperature and good homogeneity of free carrier concentration in the investigated depth. The fabricated detectors were tested for detection of fast neutrons generated by the D–T reaction. The energies of detected fast neutrons varied from 16.0 MeV to 18.3 MeV according to the acceleration potential of deuterons, which increased from 600 kV up to 2 MV. Detection of fast neutrons in the SiC detector is caused by the elastic and inelastic scattering on the silicon or carbide component of the detector material. Another possibility that increases the detection efficiency is the use of a conversion layer. In our measurements, we glued a HDPE (high density polyethylene) conversion layer on the detector Schottky contact to transform fast neutrons to protons. Hydrogen atoms contained in the conversion layer have a high probability of interaction with neutrons through elastic scattering. Secondary generated protons flying to the detector can be easily detected. The detection properties of detectors with and without the HDPE conversion layer were compared.

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37

Vainoris, Modestas, Natalia Tsyntsaru, and Henrikas Cesiulis. "Modified Electrodeposited Cobalt Foam Coatings as Sensors for Detection of Free Chlorine in Water." Coatings 9, no. 5 (May 8, 2019): 306. http://dx.doi.org/10.3390/coatings9050306.

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Metal foams offer a substantial specific surface area and sturdy frame, which makes them great candidates for various applications such as catalysts, sensors, heat sinks, etc. Cobalt and its various compounds are being considered as a cheaper alternative for precious and rare metal catalysts. The cobalt foams have been electrodeposited under galvanostatic and current pulse modes; the porous surface was created using a dynamic hydrogen bubble template. In order to obtain the highest porosity, four different solutions were tested, as well as a wide current density window (0.6–2.5 A/cm²), in addition many different combinations of pulse durations were applied. The effects of surfactant (isopropanol) on porosity were also investigated. The morphology of obtained foams was examined by SEM coupled with EDS, and XRD spectroscopy. True surface area was estimated based on the values of a double electric layer capacitance that was extracted from EIS data. Cobalt foams were modified using K3[Fe(CN)6] solution and cyclic voltammetry to form a cobalt hexacyanoferrate complex on the foam surface. In order to find optimal modification conditions, various potential scan rates and numbers of cycles were tested as well. Free chlorine sensing capabilities were evaluated using chronoamperometry.

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38

Patricio, Jonathan N., Eduardo C. Atayde Jr., Menandro C. Marquez, and Susan D. Arco. "Carbon/GO Composite Electrodes and Electrospun Polyacrylonitrile Nanofibrous Electrolyte Membranes Doped with Halogen-Free Imidazole-Based Ionic Liquid for Supercapacitor Device Fabrication." Materials Science Forum 936 (October 2018): 82–87. http://dx.doi.org/10.4028/www.scientific.net/msf.936.82.

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In this paper, we report the preparation of 1-methylimidazolium acetate (MIMOAc) through solvent-free sonochemical synthesis and its characterization using1H-NMR,13C-NMR and FTIR-ATR spectroscopy. Its effects on the morphological, structural and electrochemical properties of electrospun polyacrylonitrile (PAN) fibers were also investigated. SEM and AFM results showed that the MIMOAc-doped PAN fibers produced are thinner than that of the pristine PAN hence allowing more surface area for ion mobility. Its electrochemical performance compared well to the obtained results in preference to the conventional 1M KOH(aq)as aqueous electrolyte. The fabrication of a novel supercapacitor prototype following an electrical double-layer capacitor configuration assembled by mechanically pressing the electrospun MIMOAc/PAN nanofiber membranes between two activated carbon/graphene oxide (GO) composite electrodes on ITO-coated glass current collectors was presented in detail.

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39

Satpati, A. K., and A. V. R. Reddy. "Electrochemical Study on Corrosion Inhibition of Copper in Hydrochloric Acid Medium and the Rotating Ring-Disc Voltammetry for Studying the Dissolution." International Journal of Electrochemistry 2011 (2011): 1–8. http://dx.doi.org/10.4061/2011/173462.

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Dissolution characteristics of copper in hydrochloric acid medium and the effect of 4-amino 1,2,4-triazole (ATA) on the corrosion process have been studied using conventional electrochemical techniques and rotating ring-disc electrodes (RRDEs). Corrosion potential () and corrosion current density () were obtained by Tafel extrapolation methods. Charge transfer resistance () and double-layer capacitance () were obtained from the electrochemical impedance spectroscopy (EIS). ATA was shown to be an effective inhibitor for the copper-corrosion inhibition in acid medium. The corrosion rate was retarded in presence of inhibitors mainly because of the adsorption of the inhibitor on the electrode surface. Adsorption of the inhibitor on the metal surface was found to follow the Langmuir adsorption isotherm. Standard free energy change of the adsorption process () was calculated to be −54.3 kJ mol−1; such a large negative value of suggests the prescence of a chemisorption process.

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40

Lee, Seung Won, Jihye Jang, Yeonji Kim, Seokyeong Lee, Kyuho Lee, Hyowon Han, Hyeokjung Lee, et al. "Intrinsically stretchable ionoelastomer junction logic gate synchronously deformable with liquid metal." Applied Physics Reviews 9, no. 4 (December 2022): 041404. http://dx.doi.org/10.1063/5.0104765.

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Liquid-free ionic conductors, known as ionoelastomers, are of great interest because of their potential for developing reliable and resilient ionic devices with elastic mechanical properties. This study presents an intrinsically stretchable diode consisting of a highly stretchable ionoelastomer bilayer vertically stacked with liquid metal electrodes. The bilayer contains two types of ionoelastomer networks: one containing fixed anions with mobile cations and one containing fixed cations with mobile anions. Both ionoelastomers use 2-hydroxyethyl acrylate to provide high stretchability. The junction between the two ionoelastomers creates a diode with excellent non-Faradaic ionic current rectification. The voltage-dependent modulation of the ionic double layer at the interface between the two ionoelastomers provides the rectification. The elastic diode works under cyclic loading to a uniaxial stretch ratio of 6 (strain of 500%), allowing the development of a highly stretchable ionic OR logic gate.

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Mishra, L. N. "Retarded Field Energy Analyzer as a tool to Study the Ion Velocity Distribution Functions on Radio Frequency Argon Plasma in Expanding Magnetic Field at Low Pressures." Journal of Nepal Physical Society 3, no. 1 (January 28, 2016): 82. http://dx.doi.org/10.3126/jnphyssoc.v3i1.14447.

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<p>Plasma expanding in the space along the magnetic filed is well known phenomenon. This plasma device was constructed to investigate the space plasma in laboratory in connection with plasma flows, electron distribution, ion distribution, instability and turbulence. For this purpose, the low-temperature plasma is produced by means of a 13.56 MHz Helicon plasma source at 300-1000 W rf power. The plasma is expanding from the 13.5 cm diameter source into a 150 cm long chamber of 60 cm diameter. Ion energy and its velocity distribution produced by a current-free double layer at the expansion region have been studied by means of retarding field energy analyzers. Furthermore, the effects due to the geometrical shape of the expanding magnetic field in plasma flows have also been investigated.</p><p>Journal of Nepal Physical Society Vol.3(1) 2015: 82-88</p>

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42

Kao, Sheng-Hung, Krishnan Shanmugam Anuratha, Sung-Yen Wei, Jeng-Yu Lin, and Chien-Kuo Hsieh. "Facile and Rapid Electrochemical Conversion of Ni into Ni(OH)2 Thin Film as the Catalyst for Direct Growth of Carbon Nanotubes on Ni Foam for Supercapacitors." Nanomaterials 12, no. 21 (November 2, 2022): 3867. http://dx.doi.org/10.3390/nano12213867.

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In this paper, a facile and rapid aqueous-based electrochemical technique was used for the phase conversion of Ni into Ni(OH)2 thin film. The Ni(OH)2 thin film was directly converted and coated onto the network surface of Ni foam (NF) via the self-hydroxylation process under alkaline conditions using a simple cyclic voltammetry (CV) strategy. The as-formed and coated Ni(OH)2 thin film on the NF was used as the catalyst layer for the direct growth of carbon nanotubes (CNTs). The self-converted Ni(OH)2 thin film is a good catalytic layer for the growth of CNTs due to the fact that the OH− of the Ni(OH)2 can be reduced to H2O to promote the growth of CNTs during the CVD process, and therefore enabling the dense and uniform CNTs growth on the NF substrate. This binder-free CNTs/NF electrode displayed outstanding behavior as an electric double-layer capacitor (EDLC) due to the large surface area of the CNTs, showing excellent specific capacitance values of 737.4 mF cm−2 in the three-electrode configuration and 319.1 mF cm−2 in the two-electrode configuration, at the current density of 1 mA cm−2 in a 6 M KOH electrolyte. The CNTs/NF electrode also displayed good cycling stability, with a capacitance retention of 96.41% after 10,000 cycles, and this the excellent cycling performance can be attributed to the stable structure of the direct growth of CNTs with a strong attachment to the NF current collector, ensuring a good mechanical and electrical connection between the NF collector and the CNTs.

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Uchanin, Valentyn. "Detection of the Fatigue Cracks Initiated near the Rivet Holes by Eddy Current Inspection Techniques." Transactions on Aerospace Research 2020, no. 2 (June 1, 2020): 47–58. http://dx.doi.org/10.2478/tar-2020-0010.

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AbstractEddy current (EC) method is considered as most applicable for in-service detection of fatigue subsurface cracks initiated in aircraft multilayer structures near the rivet holes. At the same time, the successful solution of this problem is obstructed by additional noise created by defect-free rivets. All EC inspection techniques for the detection of subsurface cracks around the rivets can be classified into three main groups: 1) static mode – carried out by placing the EC probe concentrically on the rivet head; 2) rotational mode – when the EC probe is rotated around the rivet axle and 2) sliding mode – performed by the movement of EC probe along the rivet line or near it. All these approaches have some advantages and limitations. In this study, known EC techniques for the detection of cracks in multilayer aircraft structures are analyzed. New advanced EC techniques for the detection of fatigue cracks in internal layers of the riveted structures based on different types (ring, sliding, and rotational) probes are presented. The static EC method with developed low-height ring-type probe creates the possibility to detect cracks in the difficult of access areas. The possibility to estimate the length of detected cracks by a ring-type probe is shown. The proposed rotational remote field EC probe can detect as small as 1.0 mm long cracks under the button-head rivet and 2 mm thick upper skin with a high signal-to-noise ratio. Therefore, in many aircraft structures, fatigue cracks will be detected before a critical threshold achieved. New EC sliding techniques based on remote field and double differential probes were proposed for the rapid detection of cracks in internal layers of riveted aircraft structures. Remote-field EC probe for reliable detection of fatigue cracks in third and fourth layers of five-layer units was proposed. Another sliding technique based on a double differential EC probe gives the possibility to detect transverse cracks in the second layer without the rivet row area access. The main advantage of developed techniques is high inspection reliability due to the possibility to discriminate the signals created by cracks and defect-free rivets. Presented inspection procedures include the selective signal analysis in the complex plane diagram. Proposed EC inspection techniques were successfully implemented into the aircraft maintenance practice.

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Yan, You, Liu, Wang, and Wu. "Free-Standing and Heteroatoms-Doped Carbon Nanofiber Networks as a Binder-Free Flexible Electrode for High-Performance Supercapacitors." Nanomaterials 9, no. 9 (August 22, 2019): 1189. http://dx.doi.org/10.3390/nano9091189.

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Flexible and heteroatoms-doped (N, O and P) activated carbon nanofiber networks (ACFNs) have been successfully prepared with a mixture of polyamic acid (PAA) and poly(diaryloxyphosphazene) (PDPP) as a solution through electrospinning, followed by a heat post-treatment. The resultant heteroatoms-doped ACFNs can be used as binder-free electrodes for high-performance flexible supercapacitors (SCs) due to lightweight, three-dimensional open-pore structure and good mechanical strength. Despite its surface area being lower than 130.6 m2·g−1, the heteroatoms-doped ACFNs exhibited a high heteroatoms (N, O and P) content of 17.9%, resulting in a highly specific capacitance of 182 F·g−1 at a current density of 1 A·g−1 in 6 M KOH electrolyte in a two-electrode cell and an excellent rate capability of 74.7% of its initial capacitance from 1 A·g−1 to 10 A·g−1 under the mass loading of 1.5 mg·cm−2. The electrical double-layer (EDL) capacitance and pseudocapacitance can be easily decoupled in the heteroatoms-doped mesoporous ACFNs. SCs device based on heteroatoms-doped ACFNs exhibited a high energy density of 6.3 W·h·kg−1 with a power density of 250 W·kg−1, as well as excellent cycling stability with 88% capacitance retention after 10,000 charge–discharge cycles. The excellent electrochemical performance was attributed to the mesoporous structure of ACFNs and pseudocapacitive heteroatoms.

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45

Yoshino, Michitaka, Yuto Ando, Manato Deki, Toru Toyabe, Kazuo Kuriyama, Yoshio Honda, Tomoaki Nishimura, Hiroshi Amano, Tetsu Kachi, and Tohru Nakamura. "Fully Ion Implanted Normally-Off GaN DMOSFETs with ALD-Al2O3 Gate Dielectrics." Materials 12, no. 5 (February 26, 2019): 689. http://dx.doi.org/10.3390/ma12050689.

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A normally-off GaN double-implanted vertical MOSFET (DMOSFET) with an atomic layer deposition (ALD)-Al2O3 gate dielectric film on a free-standing GaN substrate fabricated by triple ion implantation is presented. The DMOSFET was formed with Si ion implanted source regions in a Mg ion implanted p-type base with N ion implanted termination regions. A maximum drain current of 115 mA/mm, maximum transconductance of 19 mS/mm at a drain voltage of 15 V, and a threshold voltage of 3.6 V were obtained for the fabricated DMOSFET with a gate length of 0.4 μm with an estimated p-type base Mg surface concentration of 5 × 1018 cm−3. The difference between calculated and measured Vths could be due to the activation ratio of ion-implanted Mg as well as Fermi level pinning and the interface state density. On-resistance of 9.3 mΩ·cm2 estimated from the linear region was also attained. Blocking voltage at off-state was 213 V. The fully ion implanted GaN DMOSFET is a promising candidate for future high-voltage and high-power applications.

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Saranin, Danila, Pavel Gostischev, Dmitry Tatarinov, Inga Ermanova, Vsevolod Mazov, Dmitry Muratov, Alexey Tameev, Denis Kuznetsov, Sergey Didenko, and Aldo Di Carlo. "Copper Iodide Interlayer for Improved Charge Extraction and Stability of Inverted Perovskite Solar Cells." Materials 12, no. 9 (April 30, 2019): 1406. http://dx.doi.org/10.3390/ma12091406.

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Nickel oxide (NiO) is one of the most promising and high-performing Hole Transporting Layer (HTL) in inverted perovskite solar cells due to ideal band alignment with perovskite absorber, wide band gap, and high mobility of charges. At the same time, however, NiO does not provide good contact and trap-free junction for hole collection. In this paper, we examine this problem by developing a double hole transport configuration with a copper iodide (CuI) interlayer for efficient surface passivation. Transient photo-current (TPC) measurements showed that Perovskite/HTL interface with CuI interlayer has an improved hole injection; CuI passivation reduces the concentration of traps and the parasitic charge accumulation that limits the flow of charges. Moreover, we found that CuI protect the HTL/perovskite interface from degradation and consequently improve the stability of the cell. The presence of CuI interlayer induces an improvement of open-circuit voltage VOC (from 1.02 V to 1.07 V), an increase of the shunt resistance RSH (100%), a reduction of the series resistance RS (−30%), and finally a +10% improvement of the solar cell efficiency.

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47

Takase, Shintaro, Kouta Miyagawa, and Hisafumi Ikeda. "Label-Free Detection of Zeptomol miRNA via Peptide Nucleic Acid Hybridization Using Novel Cyclic Voltammetry Method." Sensors 20, no. 3 (February 4, 2020): 836. http://dx.doi.org/10.3390/s20030836.

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To harness the applicability of microribonucleic acid (miRNA) as a cancer biomarker, the detection sensitivity of serum miRNA needs to be improved. This study evaluated the detection sensitivity of miRNA hybridization using cyclic voltammograms (CVs) and microelectrode array chips modified with peptide nucleic acid (PNA) probes and 6-hydroxy-1-hexanethiol. We investigated the PNA probe modification pattern on array chips using fluorescently labeled cDNA. The pattern was not uniformly spread over the working electrode (WE) and had a one-dimensional swirl-like pattern. Accordingly, we established a new ion-channel sensor model wherein the WE is negatively biased through the conductive π–π stacks of the PNA/DNA duplexes. This paper discusses the mechanism underlying the voltage shift in the CV curves based on the electric double-layer capacitance. Additionally, the novel hybridization evaluation parameter ΔE is introduced. Compared to conventional evaluation using oxidation current changes, ΔE was more sensitive. Using ΔE and a new hybridization system for ultrasmall amounts of aqueous solutions (as low as 35 pL), 140 zeptomol label-free miRNA were detected without polymerase chain reaction (PCR) amplification at an adequate sensitivity. Herein, the differences in the target molar amount and molar concentration are elucidated from the viewpoint of hybridization sensitivity.

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48

Leong, Yee-Kwong, Pengfei Liu, Pek-Ing Au, Peta Clode, and Jishan Liu. "Microstructure and Time-Dependent Behavior of STx-1b Calcium Montmorillonite Suspensions." Clays and Clay Minerals 69, no. 6 (December 2021): 787–96. http://dx.doi.org/10.1007/s42860-021-00170-5.

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AbstractCaMnt is much less important than NaMnt due to its limited commercial applications. The time-dependent property of NaMnt gel has been studied extensively as it is exploited in many applications such as drilling mud and viscosity-modifier applications. In contrast, the time-dependent property of CaMnt suspension and the factors affecting it are largely unknown. The speciation of Ca2+ ions is one such factor to be evaluated. In the current study, pH and solids concentration were examined and then used to validate a recent theory on clay gel time dependency. The results supported the theory that a strong electrostatic double layer (EDL) repulsion in the 3-D network is needed to reorganize the structure and drive it toward the state of minimum free energy. The 12 wt.% CaMnt (STx-1b) gel displayed time-dependent behavior at pH 5 but not at its natural pH of 8.4. At pH 5, the interlayer Ca2+ ions became fully hydrated and desorbed from the platelet surface. This enhanced the EDL repulsion between the platelets. At pH >6.5, the positively charged hydrolysis product Ca(OH)+ began to form and was adsorbed, partially neutralizing the permanent layer charge and weakening the repulsion. However, at 19.4 wt.% solids, the gel displayed pronounced time-dependent behavior despite the high natural pH of 8. The platelets were much closer together, allowing the EDL force to operate and effect structural reorganization. The microstructure of these CaMnt gels showed high platelet concentrations interacting to form a relatively open structure. The microstructure of a kaolin (KGa-2) suspension which showed no time-dependent behavior even after 1 day of ageing revealed the importance of particle morphology and layer charge on time dependency. Its 3-D structure was formed by relatively thick, layered platelets with a low layer charge.

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Wang, Zhiwei, and Weibin Ma. "Dynamic Response and Fatigue-Life Analysis of High-Speed Railway Tunnel Base with Defects." Mathematical Problems in Engineering 2022 (January 20, 2022): 1–20. http://dx.doi.org/10.1155/2022/6622998.

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Based on the repeated “tensile-compressive-tensile-compressive” stress characteristics of tunnel-base concrete structure, double scalar damage variables were defined using the concrete stochastic damage mechanics. The elastoplastic Helmholtz free energy was corrected by introducing the hardening parameter. A stochastic dynamic damage constitutive model with the nonlinear and strain-rate effect behavior of concrete was derived via dynamic expansion of damage energy based on the principle of energy dissipation. An “elastic prediction-plastic correction” numerical analysis algorithm was developed based on the solution of the probability density evolution equation. Secondary development of the algorithm was achieved using the Universal Distinct Element Code (UDEC) for numerical calculation of the proposed constitutive model. A comparison was made between the calculation result and the result of laboratory rapid uniaxial compression test to verify the model. Dynamic response and damage features of the tunnel-base structure in three working conditions, i.e., filled layer without seam, filled layer with seam and ground water, and filled layer with seam but without water, were analyzed based on engineering practice. According to the analysis, structural vibration response was intensified in the presence of a seam. With and without groundwater, the vertical dynamic stress attenuation at both sides of the seam was 41.07% and 47.13%, respectively; vertical vibration acceleration was attenuated by 91.17% and 91.73%, respectively; and the acceleration amplitude at the upper structure of the seam increased by 724.67% and 765.02%, respectively. Groundwater in the seam would aggravate damage accumulation. It could be seen from the analysis that the current design parameters satisfied the antifatigue requirements within the design reference period at a train speed of 300 km/h when there was no seam in the tunnel-base concrete structure with IV-class surrounding rocks. When there was a seam in the tunnel-base concrete structure, however, antifatigue life was 56 years in the presence of groundwater and 62 years without groundwater, which suggested that current design parameters failed to satisfy the antifatigue requirements within the design reference period.

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Zhou, Jianyin, Jie Xiang, and Sixun Huang. "Marine Boundary Layer Height Obtained by New Numerical Regularization Method Based on GPS Radio Occultation Data." Sensors 20, no. 17 (August 23, 2020): 4762. http://dx.doi.org/10.3390/s20174762.

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The boundary layer height (BLH) determines the interface between the lower and the free atmosphere, and it is a key variable in numerical simulations and aerosol and environmental pollution studies. This article proposes a novel method in conjunction with numerical regularization to analyze the climate characteristics of the marine boundary layer height (MBLH) using 2007–2011 GPS-RO data from the COSMIC mission. The MBLH corresponds to the smallest gradient, which is calculated using the numerical regulation method where the regulation parameters are determined by the double-parameter model function method. The results reveal the relationship between the MBLH and ocean currents for the first time. A low MBLH is associated with cold seasons and seas where cold ocean currents prevail whereas a high MBLH is related to warm seasons and seas where warm currents prevail. This correlation was validated by comparing the obtained results with different occultation data including atmprf and echprf, which also showed that atmprf is more sensitive to convective cloud top capture. To test the credibility of the results, the standard deviation was used to express the MBLH confidence level. The results show that the standard deviation of the MBLH was highest in low latitudes and lowest in the middle and high latitudes. Furthermore, we analyzed the trends in interannual MBLH variations, which display significant seasonal variations and spatial distributions that correspond with the current and subsolar point. Finally, we conducted a case study in the South China Sea, and identified a distinctive seasonal change and interannual decline in MBLH.

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Journal articles on the topic 'Current-free double layer'

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