Targeted treatment of cancer with radiofrequency electromagnetic fields amplitude-modulated at tumor-specific frequencies

In the past century, there have been many attempts to treat cancer with low levels of electric and magnetic fields. We have developed noninvasive biofeedback examination devices and techniques and discovered that patients with the same tumor type exhibit biofeedback responses to the same, precise frequencies. Intrabuccal administration of 27.12 MHz radiofrequency(RF) electromagnetic fields(EMF), which are amplitude-modulated at tumor-specific frequencies, results in long-term objective responses in patients with cancer and is not associated with any significant adverse effects. Intrabuccal administration allows for therapeutic delivery of very low and safe levels of EMF throughout the body as exemplified by responses observed in the femur, liver, adrenal glands, and lungs. In vitro studies have demonstrated that tumor-specific frequencies identified in patients with various forms of cancer are capable of blocking the growth of tumor cells in a tissue- and tumor-specific fashion. Current experimental evidence suggests that tumor-specific modulation frequencies regulate the expression of genes involved in migration and invasion and disrupt the mitotic spindle. This novel targeted treatment approach is emerging as an appealing therapeutic option for patients with advanced cancer given its excellent tolerability. Dissection of the molecular mechanisms accounting for the anti-cancer effects of tumor-specific modulation frequencies is likely to lead to the discovery of novel pathways in cancer.

Effect of turbulent flow on electromagnetic elimination with high frequency magnetic field

The results of experiments and simulations show that there is a turbulent flow in the molten aluminum and it is hard to be restrained in the thin tubule (diameter of 6 mm) when the electromagnetic body force is applied. The electromagnetic elimination experimental results show that the flow has serious effect on the elimination of 5 μm alumina inclusions, but has little effect on the 30 μm and 100 μm primary silicon. The effects of the electromagnetic field and the turbulent flow on the electromagnetic elimination are discussed.

Continuous cleaning of A356 alloy melt using high frequency electromagnetic field

A set of device for electromagnetic separation (EMS) was designed and applied to process the continuous flowing melt. Tensile test was employed to compare effect of electromagnetic separation with that of the traditional processes. Compared with filtration by ceramic foam filter and process without filtration, multiple process combined with filtration and electromagnetic separation can effectively remove most of inclusions with diameter finer than 10 μm in A356 alloy casting, hence improve its tensile properties. After being processed by electromagnetic filtration, the tensile strength of A356 scrap is enhanced by 8.27%, approaching the level of fresh A356 alloy.

Monitoring Electromagnetic Field Emitted by High Frequencies Home Utilities

The aim of this study is to provide measurements of the electromagnetic field due to the ‘electrosmog’ emitted by some home electronic devices in the range of microwaves frequencies. The enormous increase in the use of mobile telephony throughout the world, microwave ovens, cordless phones and other high frequency home utilities suggests accurate measures of microwaves power density emitted by such devices to check that the exposure limits suggested by the In-ternational Commission on Non-Ionizing Radiation Protection are not exceeded. Measurements were carried out by a Narda SRM 3000. Spectrum analysis mode was chosen as a preliminary analysis to quantify the frequencies intensities of electromagnetic waves. Time analysis was successively conducted to operate selective and continuous measurements at a fixed frequency, allowing temporal check of power density and the related electromagnetic field components emitted by high frequencies home electronic devices.

Separation efficiency of alumina particles in Al melt under high frequency magnetic field

The effects of separation time and magnetic induction intensity on the separation efficiency of alumina particles with diameters varying from 30 to 200 μm in aluminum melt were investigated. The experimental results show that the particle-accumulated layer is formed in the periphery of the solidified specimen when the diameter of the separated molten metal, the magnetic induction intensity and the separation time are 10 mm, 0.04 T and 1 s, respectively. When the separation time is 2 s, the particle-accumulated layer can be observed obviously and the separation efficiency is about 80%. There are few alumina particles in the inner of the solidified specimen when the separation time is 3 s. The separation efficiency higher than 85% can be achieved when the separation time is longer than 3 s. When the magnetic induction intensity is 0.06 T, the visible particle-accumulated layer can be formed in 1 s and the separation efficiency is higher than 95%. The experimental results were compared with the calculated results at last.

DISCHARGE CHANNEL GROWTH IN MICRO EDM OF HIGH FREQUENCY PULSE

The influences of intense magnetic pinch effect caused by electromagnetic field with high frequency on discharge channel expansion and plasma configuration change are discussed. The change of Lorentz force exerting on charged particles in discharge channel is calculated under the electromagnetic field with high frequency. Through the theoretical analysis and experimental study, the forming process of discharge channel is conjectured. And it is considered that the changes of discharge channel, such as the decrease of diameter and increase of energy density, coming from the intense magnetic pinch effect in high frequency electromagnetic field, are the main reasons for a series of special phenomena on the machined surface in micro EDM.

Numerical simulation of applied electromagnetic field and electromagnetic force in all-position welding

All-position welding is an important technology in energy sources, chemical, shipbuilding and other industries. When welding current is larger than 200 A, the molten metal tends to flow down due to the force of gravity. In order to ＂push＂ the molten metal into the weld, a new kind of U-frame excitation model, which could produce electromagnetic force to balance the gravity of the molten pool, was designed. The related parameters of the excitation model were simulated by Maxwell 3D, and the relationships between the parameters and the magnetic induction intensity were analyzed. Finally, the electromagnetic force in the molten pool was calculated, and the appropriate parameters of the U-frame excitation model were determined. The results of the simulation verify the feasibility of the all-position welding excitation model.

Effect of Hot Carrier on Amplitude Modulation and Demodulation of Gaussian High Power Helicon Wave in Homogeneous Longitudinally Magnetized Strain Dependent Dielectric Material

In the present communication, the hydrodynamic model is used to investigate the amplitude modulation as well as demodulation of an electromagnetic wave of high power helicon pump wave into another helicon wave in strain dependent dielectric material incorporating carrier heating (CH) effects. The consideration of CH in modulation and demodulation is prime importance for the adding of new dimension in analysis of amplification of acoustic helicon wave. By using the dispersion relation, threshold pump electric filed and growth rate of unstable mode from the modulation and demodulation of the high power helicon wave well above from the threshold value will be discussed in the present analysis. The numerical analysis is applied to a strain dependent dielectric material, BaTiO3 at room temperature and irradiated with high power helicon wave of frequency 1.78 × 1014 Hz. This material is very sensitive to the pump intensities, therefore during studies, Gaussian shape of the helicon pump wave is considered during the propagation in stain dependent dielectric material and opto-acoustic wave in the form of Gaussian profile (ω0,κ0) is induced longitudinally along the crystallographic plane of BaTiO3. Its variation is caused by the available magnetic field (ωc), interaction length (z) and pulsed duration of interaction (τ). From the analysis of numerical results, the incorporation of CH effect can effectively modify the magnitude of modulation or demodulation of the amplitude of high power helicon laser wave through diffusion process. Not only the amplitude modulation and demodulation of the wave, the diffusion of the CH effectively modifies the growth rate of unstable mode of frequency in BaTiO3. The propagation of the threshold electric field shows the sinusoidal or complete Gaussian profile, whereas this profile is found to be completely lost in growth of unstable mode. It has also been seen that the growth rate is observed to be of the order of 108 - 1010 s-1 but from diffusion of carrier heating, and that its order is enhanced from 1010 - 1012 s-1 with the variation of the magnetized frequency from 1 to 2.5 × 1014 Hz.

Analysis and Simulation of the Influence of Electromagnetic Fields on Living Beings near HV Power Lines Using the FDTD Method

Recent decades have seen rapid advances in the field of electrical engineering, such that our environment has become a sea of electrical and magnetic signals, raising questions about the possible effects of low-frequency electromagnetic fields on the environment and which are capable of modifying and destroying our ecosystem. Particular interest was given in this article due to a massive influx of population living near high voltage lines. The analysis and simulation of the influence of low frequency electromagnetic fields on living beings in the vicinity of high voltage sources 132 kV and 220 kV in urban areas in DR Congo is the subject of our research with a view to estimating the level of exposure of humans to low frequency electromagnetic fields. To carry out our research, we used the classic method of analyzing the field produced near a high voltage line based on Maxwell’s image theory, the Maxwell-Gauss theorem and Maxwell-Ampère theorem to model and quantify low-frequency electromagnetic fields in the vicinity of high-voltage lines. The 2D FDTD numerical formulation was developed from telegraphers’ equations and allowed us to obtain models of current and voltage induced by electromagnetic fields on living beings below and near HV lines. The different simulations carried out on the proposed models illustrate the effects of the electrical and geometric parameters of the pylons on the distribution of the electromagnetic field in the vicinity of the HV lines. The results obtained were compared to the safety limits recommended by the standards.

Electromagnetically induced transparency induced by a 100% amplitude-modulated coupling field

We present a study of electromagnetically induced transparency(EIT) under the excitation of a 100% amplitude-modulated(AM) coupling field.The EIT feature is associated with a Λ type three-level configuration where a coupling and probe field couples two separate optical transitions and it is well-known that the spectrum of the swept probe field gives a simple single transparency feature induced by the single mode coupling field.It is shown that when a 100% AM coupling field is applied,there is an EIT doublet...

Parametric Instability of a Liquid Metal Sessile Drop Under a High Frequency Amplitude-Modulate Magnetic Field

The parametric instability behavior of a liquid mercury sessile drop under high frequency Amplitude-Modulate Magnetic Field(AMMF),i.e.a high frequency magnetic field(carder wave)modulated by a low frequency sine wave(modulate wave),is investigated experimentally.The free surface contour of the mercury drop is observed by a CCD camera while varying the frequency and amplitude of the high frequency AMMF.At a given frequency and amplitude,the edge deformations with an azimuthal wave numbers(modes n=3,4,5,6)were excited.

高频变压器电磁场-结构力场-声场求解及特性分析

大容量高频变压器结构紧凑,工作频率为数百Hz到几十kHz,工作波形为方波等非正弦的特殊激励波形。高频变压器电磁、结构、声等多场耦合紧密,运行时出现严重的振动与噪声问题,对高频变压器振动与噪声特性进行精细分析对于其减振降噪具有重要意义。为此,该文首先建立高频变压器电磁场-结构力场-声场3维仿真求解模型,明确各物理场的载荷传递过程以及电磁和力学性能参数;然后,采用有限元法得到不同电压激励下变压器铁芯表面时域振动波形与噪声频域特性,并定量评估了纳米晶切割铁芯对受力特性的影响程度;最后,对1台5 kHz/10 kVA高频变压器的振动和噪声进行试验测试,得到正弦和方波电压激励下铁芯振动和噪声数据。由仿真与试验结果可知,高频变压器铁芯拐角处振动较为剧烈且周围产生的噪声也较大;相比于正弦波激励,非正弦波激励下的振动不仅集中发生在2倍频,还存在许多高次谐波分量,同时各个频率段声压级明显增加;不同波形激励下测量点声压级相对误差均在10%以内,验证了仿真模型的准确性。

航空发动机电子控制器的高强辐射场干扰及防护

针对航空发动机电子控制器(EEC)易受高强辐射场(HIRF)干扰问题,以ZF-M600型EEC为研究对象,通过三维电磁仿真软件CST对EEC建模并进行平面波辐照仿真,模拟HIRF对EEC的干扰效应,仿真结果表明,HIRF可以通过孔缝耦合进入EEC内部并在腔体内部产生谐振,谐振频率处电场强度显著增加。依据RTCA DO-160G在400 MHz~4 GHz开展EEC辐射敏感度试验,试验结果表明:EEC失效频点为2.40 GHz和3.48 GHz,敏感模块为模拟量输入输出模块,敏感现象为模拟量数据丢失。EEC失效频点与谐振频率接近,说明EEC失效与腔体谐振有关,在EEC内部贴装吸波材料并进行仿真,分析吸波材料的放置方式和厚度对EEC谐振电磁干扰强度的影响,仿真结果表明,贴装吸波材料可以有效抑制谐振电磁干扰。

带散射体的电力系统多级传输线高频耦合模型

高频电磁场会与架空输电线路产生耦合,一旦高频电磁场的波长小于传输线的高度,经典传输线理论就不再适用。传统的全波数值算法虽然可以解决这一问题,但求解效率不高,需要消耗大量的时间与计算资源。此外,电力系统输电线路往往有多个垂直端,线路布局复杂,而以往针对电力系统传输线的高效求解研究都是只有左右两个垂直端的较为简单的模型,与实际电力系统传输线的结构不符,没有考虑中间带有垂直端的情况。为了解决这些问题,文中提出一种理论有效的方法来解决有损耗地面上方带有散射体的电力系统多级传输线的高频电磁场耦合问题。采用计算效率高的渐近法,并在渐近法中引入散射体的概念,以考虑更复杂的电路结构。最后通过数值算例验证了该方法的准确性和有效性。

基于FPGA的可调点频信号产生器

高频正弦波信号产生器在高频电子线路中通常作为载波信号源来使用,是一种必不可少的测试信号源和激励源,基于此设计了一种频率可调、幅度可调的正弦信号产生器。采用现场可编程门阵列(FPGA)产生数字波形信号,在Quartus Prime集成开发环境下,采用Verilog硬件描述语言,基于Modelsim仿真软件上进行了仿真实现。并基于Altera公司Cyclone IV系列的EP4CE30F23C7 FPGA进行了测试,使用Signal Tap逻辑分析仪采集并显示FPGA设计中的实时信号行为。测试结果表明,该信号产生器能输出频率为250、500、750、1000、1500 MHz,幅度为1、1/2、1/4、1/8、1/16的高频正弦波信号。

基于混合式调制的矩阵变换器谐波抑制方法

矩阵变换器在通过输入电压高频调制合成输出电压过程中不可避免地会出现高频谐波,该谐波不仅影响输出侧性能,也会通过矩阵变换器双向开关的切换降低输入侧性能。针对上述问题,提出一种混合式调制方法用以改善矩阵变换器输出侧性能。首先,详细分析了抑制幅值最大相频繁开通调制方法的工作原理及在抑制输出侧高频谐波方面的不足;其次,提出通过对输入输出扇区的判断,在不同扇区内分别采用减少开关管切换次数和避免幅值最大相频繁切换的混合式调制方法,分析并推导该调制方法下的开关序列分布规律及作用时间表达式;最后,搭建样机进行试验验证,试验结果表明利用所提混合式调制方法来进一步抑制输出侧高频谐波是可行且有效的。

变频驱动下电机高频径向电磁力波研究

采用场路耦合法对永磁同步电机高频径向电磁力特征频率产生原因和主要组成成分进行研究。通过解析法分析谐波电流的产生机理及谐波特性,并利用数值仿真对其进行验证;结合磁动势−磁导法和麦克斯韦张量法分析出高频径向电磁力特征频率的分布;对有限元计算得到的气隙磁场进行时空分解,采用麦克斯韦张量法计算磁场相互作用产生的高频径向电磁力。结果表明,变频驱动下永磁同步电机的高频径向电磁力主要是由变频器谐波电流引入的谐波磁场和定子基波磁场的相互作用产生,这对永磁同步电机的研究提供了一定的指导意义。

基于频率差的工频磁场抗扰度试验方法

现有工频磁场抗扰度试验方法评价受试设备在工频磁场骚扰下的采样性能时,试验结果随机,可能出现误判。结合GB/T 17626.8-2006要求、试验方法及试验仪器的特点,文章分析了试验结果出现随机现象的原因。在此基础上,提出了基于受试设备基本分量及干扰分量频率差的工频磁场抗扰度试验方法。多种电气二次设备的工频磁场抗扰度试验结果表明,频率差法通过人为合理设置频率差,在受试设备的正常使用状态下,可有效检测出工频磁场骚扰对受试设备的最大影响程度,消除了试验结果的随机性。频率差法适应性好、操作简便,不仅适用于电力工业领域,也有利于形成具有良好的共同性和重复性的基准。

评估电动汽车GPS天线对人体产生的比吸收率

电动汽车作为新能源汽车的代表,已经成为全球主要经济体认可的发展方向,而车载天线在车辆通信中起着关键作用,支持无线电话通信、GPS导航、无线数据传输等功能,提供更便捷、安全、智能化的驾驶体验。目前GPS全球定位系统广泛应用于电动汽车导航,由于GPS天线的工作频率为1.575 GHz,车内乘客在这种高频电磁暴露下的健康风险令人担忧。构建GPS天线、电动汽车、人体模型,通过在有限元仿真软件COMSOL Multiphysics中进行频域和瞬态分析的多物理场耦合计算,得到电动汽车内3个位置的人体在受到GPS天线辐射30 min后的比吸收率(SAR)分布。结果得出30 min全身平均SAR为0.0036 W/kg,是ICNIRP限值的4.5%,说明车载GPS天线的电磁暴露不会对人体健康造成威胁。

高速铁路接触网工频电磁场数值模拟与分析

为了分析高速铁路接触网周围工频电磁场的分布特征,从骚扰源和骚扰对象出发,利用有限元分析软件COMSOL Multiphysics架构接触线与钢轨的三维几何空间模型,在接触线承载1000A计算电流的条件下求得接触线周围工频磁场分布,得出钢轨表面和线路中心线的磁感应强度大小。仿真结果表明,磁场主要分布在Z、Y两轴方向,在Z轴方向,磁感应强度在接触线附近达到最大值并在周围逐渐减小,在距钢轨表面约300mm的(Z=300mm)平面上减小到最小值,接近钢轨表面磁感应强度逐渐增大;在接触线附近Y轴方向,钢轨外表面(Y=0mm)处出现最大值,两侧呈现衰减变化,外侧减小速率大于内侧,内侧大约在距钢轨外表面300mm处减小到最小值,并逐渐增大直至接触线表面附近,在接触线内部出现最小值。可见高速铁路接触网周围工频电磁暴露不会对公众健康构成威胁。