In this paper, a wideband 220-GHz sheet-beam traveling-wave tube (TWT) based on staggered double vane slow-wave structure (SWS) is investigated. A novel method of loading the attenuator into SWS for suppressing backward wave oscillation proposed. addition, focusing electrode sheet beam gun carried out in which whole but divided two parts artificially, one used to compress electron <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">...

The principal bioeffect of the nanosecond pulsed electric field (nsPEF) is a lasting cell membrane permeabilization, which often attributed to formation nanometer-sized pores. Such pores may be too small for detection by uptake fluorescent dyes. We tested if Ca2+, Cd2+, Zn2+, and Ba2+ ions can used as nanoporation markers. Time-lapse imaging was performed in CHO, BPAE, HEK cells loaded with Fluo-4, Calbryte, or Fluo-8 Ca2+ did not change fluorescence intact cells, whereas their entry after...

The question of whether terahertz (THz) waves can interact with ions in channels nerve cells and cause a further reaction has attracted much attention. To answer this question, we investigate the spontaneous radiation generated by Ca2+ moving calcium effect THz on transport solving mathematical physical model through Brownian dynamics (BD) simulations. It is obtained that channel generate electromagnetic radiation, corresponding spectrum which concentrated range. Meanwhile, both ion number...

This paper simulates Ca <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2+</sup> transmembrane transport through voltage-gated channels in response to terahertz electromagnetic irradiation. The active of ions is taken into considerations the transport. Temperature variations due loss physiological medium are simulated. interaction between fields and mobile at cellular level deduced from relativistic electrodynamics. It shows that effects 0.1 ~ 3...

Intense terahertz radiation was applied to trigger transient proton transfer in DNA base pairs through quantum simulation.

In this paper, a high-power Ka-band traveling-wave tube (TWT) driven by sheet electron beam is proposed and demonstrated means of the simulation experimental methods. The single grating rectangular waveguide with large width-to-height ratio used as slow-wave structure (SWS). An <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$E$ </tex-math></inline-formula> -plane bend energy coupler put forward to feed...

Irradiation of terahertz electromagnetic wave including its short-wave band in infrared shows broad and important application prospects biological science due to noninvasive nonionizing nature. Cell membrane is an barrier for keeping cell integrity homeostasis, it also the cellular structure that fields act first on case irradiation. The responses are mechanisms most effects First, this paper expatiated safety irradiation new life medicine, neural regulation artificial intelligence. Then,...

The voltage-gated calcium influxes modulated with terahertz Gaussian pulse is presented in this paper, and temperature rise evaluated to monitor the thermal effects involved modulation. From numerical results, inhibition effect on influx because of loss from electric drift transparently revealed modulation pulse. And becomes significant reflected by considerable reduction as irradiated amplitude raised intense enough. Compared sinusoidal wave, reduces dramatically. decrease increment...

Terahertz science and technology has recently shown new application prospects in artificial intelligence. It is found that terahertz unipolar stimulation can activate cell membrane hydrophilic pores. However, the behaviors of Na+, K+-ATPase energy consumption during this period remain unknown. This paper investigates these by electroporation models, based on interaction theory between fields ions at cellular level. The effective diameters life are considered aqueous solution. From results,...

It has been observed through animal and cell experiments that terahertz electric pulse irradiation can modulate physiological processes of nerve system. However, the regulation mechanism is unclear corresponding research rarely reported in literatures. This paper simulates voltage-activated calcium flux rodent neuroblastoma cells under 50ps, 2.5THz pulses. The active transport ions on plasma membrane considered simulation. numerical results indicate lead to alternate activation channels both...

It is observed that nanosecond pulsed electric field induces extracellular calcium inflow, which suggests great potential in manipulating cell functions. In this paper, a mathematical model of transmembrane transport set up to make systematic research through voltage-gated channels (VGCCs) response electrical pulses. The particle-in-cell simulation method employed simulate the process and obtain concentration at any time. results show pulse can activate low VGCCs during radiation period....

The radial divergent sheet beam electron optical system focused by a uniform magnetic field is designed in this paper. It shown that the with size of 8 deg×0.23 mm, generated gun 1700V, 151 mA, can stably pass through drift tunnel transverse 20 deg×0.52 mm and length quasi-uniform field.

Currently, it is indicated that terahertz irradiation capable of permeabilizing cell membrane by electroporation, which able to facilitate transmembrane transport molecules and ions for medicine clinical applications. This paper numerically studies the changes in permeability owing hydrophilic pores electroporation response picosecond pulse train. The capacitive current ion channel currents are taken into account simulation conductance pores. numerical results reveal increases firstly at...

In this paper, a mathematical physics model is set up to study dielectric constant profile of aqueous solvent in ionic solution, revise Brownian dynamics simulation solution by considering time-variant with change ion positions, and the effect high-intensity electric pulses on profile. The validation confirmed verification calculations. By means proposed model, profiles calcium chloride sodium solutions their response are simulated. Based numerical results, constants spatially vary instead...

Analysis of a Ka-band relativistic sheet beam traveling-wave-tube (RTWT) by simulation method is presented in this paper. The single grating rectangular waveguide chosen for its slow wave structure (SWS) due to flat shape, better transmission characteristics and superiority fabrication, mechanical robustness. high-frequency characteristic the single-grating rectangular, RTWT interaction performance are investigated respectively.

This paper presents a 0.22THz big beam-tunnel folded-waveguide (FWG) traveling-wave tube (TWT) with phase-velocity taper. The beam tunnel was applied in order to reduce the processing difficulty and increase capability of direct current power. And input output coupling structures attenuator were simulated entire transmission characteristic analyzed by employing high-frequency simulation software (HFSS). Moreover, phase velocity taper put into use for purpose both being easy be fabricated...

This paper presents 140-GHz and 220-GHz folded-waveguide(FWG) traveling wave tubes (TWT) with big electron beam tunnels, whose high frequency characteristics beam-wave interaction are calculated by using equivalent circuit method 3-D particle-in-cell (PIC) code. From the calculations, beam-tunnel FWG could produce about 25.36dB 26.94dB gain respectively under condition of uniform slow-wave structure(SWS). And a proper phase-velocity taper used in FWG, output power at center is improved up to...

A new method to improve the resolution for microwave imaging is proposed in this paper by means of a water-immersed orbital angular momentum horn antenna. In order determine suitable wavelength interrogating radiation medium and reduce big reflection incident energy at interface between target surrounding target, 2.45GHz selected chosen as water paper. Moreover, different orders OAM may carry more characteristic information exposed object imaging. The antenna simulated, calculation results...

A new method that can significantly improve the microwave biological imaging resolution is provided by means of water-immersed orbital angular momentum (OAM) circular antenna array. Considering penetration depth and reflection at interface between tissue environment, 2.45GHz selected as central frequency OAM array which assumed to be immersed in water. Some important simulation results are presented here, purity modes with respect different states calculated from these results. The proposed...

Studying the characteristics of cell membrane in terahertz band using finite-difference-time-domain (FDTD) method have revealed a significant differences between different hydration degree. These are manifested reflected pulse due to changes refractive index and absorption. And effect on wave is mainly frequency higher than 30 THz. Subcell FDTD modeling adopted this paper deal with as kind thin layer band. Simulating interaction radiation hydrated key step toward understanding interactions cells.