Crystal Structure and Antimicrobial Properties of Rare Earths Aryl-acylhydrazone Complexes under Microwave Irradiation

2-Carbonyl propionic acid-4-methyl benzoyl hydrazone （PAMH） has been synthe-sized by using 4-methyl benzoyl hydrazine and pyruvic acid as the chemicals and acetic acid asphase transfer catalyst under microwave radiation. Then the PAMH and TbCl3·6H20 are placed inthe methanol/acetone/water （3：2：4） mixture for coordination reaction, getting the Schiff complexTb（PAMH）3. The crystal structure is characterized by elemental analysis, X-ray Diffraction （XRD）and infrared spectrum. The compound crystallizes in the monoclinic space group P21/n, with a =1.4770（4）, b = 1.2864（3）, c = 1.9287（5） nm, β= 92.06（3）°, V= 3.6623（15） nm3 and Z= 4. Tb（Ⅲ） ionis nona-coordinated by three completely deprotonated PAMH ligands in a tricapped trigonal prismgeometry, leaving a zero-dimensional mononuclear configuration. The optical properties and thermalstability are studied by ultraviolet spectrum, fluorescence spectra and thermogravimetric analysis（TGA）. The antibacterial activities of the ligand and rare-earth complex are preliminarily studied,and found they have certain antibacterial activity on fusarium solani, and the complex is obviouslymore effective in suppressing fusarium solani than the ligand.

BP Neural Network Based on Microwave Method for Measuring the Moisture Content of Textile

The moisture content of yarn and fabric is an important factor in textiles industry.A novel microwave method used for material moisture content measurements is described in this paper.It can estimate the moisture content of the yarn roll with a standard deviation of 1.58% in the range of 0% to 90.00%.According to the actual size of the yarn,the yarn roll simulation model is established.The microwave attenuation variations arising from the changes in the conductivity and dielectric constant of the wet cone yarn from1.8 GHz to 5.0 GHz frequency are obtained by ultra-wideband antenna.The measured data are analyzed using the BP neural network.The result shows that it is a non-contact and online method to solve the moisture content of the yarn in the wide moisture content range.

Deployable Antenna with Compact Ortho-mode Transducer and Feeding Systems

The compact ortho-mode transducer (OMT) and compact conical corrugated horn(CCCH) are used as feeding system of the deployable dual polarizing antenna in this paper.A new stricture of double-septum in main wave guide OMT is proposed. The finite difference method in time domain (FDTD) in combination with genetic algorithms(GAs) is used to analysis and optimize this new OMT. The experiment results show that the voltage standing wave ratio (VSWR) of this OMT and feeding system is less than 1.17 in bandwidth; the isolation between the ortho-mode ports is less than -40dB; the cross-polar level of the feed can reach -35dB and the length of the main waveguide can be reduced 50% at least.

In-port-plug transmission line design of the ITER plasma position reflectometer

This work describes the microwave design of the transmission line housed in the in-port-plug region of the ITER plasma position reflectometer(PPR).The design of the components of the inport-plug reflectometers(located in equatorial port-plug 10(EPP10) and in upper-port-plug 01(UPP01)) is presented.Using a 3 D ray tracing code, the spatial position and optimum orientation angles of each set of emission and detection antennas were determined.A feasible path was then created from the obtained antenna positions and orientations to the primary vacuum window.Oversized tall waveguides were chosen to reduce ohmic losses.Due to space constraints in the ITER crowded environment, bends in oversized waveguides were unavoidable, and thus mode conversion was produced.To keep mode conversion losses at bay, hyperbolic secant curvature bends had to be used whenever possible.However, E-plane bends in tall waveguides proved to be especially critical, making it necessary to employ other approaches when higher bending angles were needed.Mode conversion results were obtained by evaluating the mode coupling equations.Ohmic losses have also been computed and their results compared with commercial simulators, obtaining a perfect agreement.

Excitation of anti-symmetric coupled spoof SPPs in 3D SIS waveguides based on coupling

According to the electromagnetic field distributions, there exist two kinds of coupled spoof surface plasmon polaritons（SSPPs）, the symmetric and anti-symmetric modes, in the three-dimensional（3D） subwavelength spoof–insulator–spoof（SIS） waveguide. We study the dispersion and excitation of the two kinds of coupled SSPPs supported by the 3D SIS waveguide. The evolution of the dispersion with the thickness and gap width of the waveguide is numerically investigated,and we give a theoretical analysis according to the coupling mechanism. Specially, based on the coupling mechanism,we design a zipper structure, through which the excitation and propagation of the anti-symmetric coupled modes can be realized effectively.

Research progress of microwave plasma ignition and assisted combustion

As the low temperature non-equilibrium plasma,microwave plasma has the same effects with the plasma produced by the traditional high voltage electrode,which has the function of widening ignition boundary and improving combustion.Microwave has the advantages of uniformity,particle selectivity and no electrode.It can generate a large range of non-equilibrium plasma with relatively low power without electrode ablation.Therefore,how to maximize its effectiveness has become the research hotspot of ignition and combustion in engines.At present,the related research mainly focuses on microwave plasma discharge and microwave assisted spark ignition.The results show that it can broaden lean and rich burn flammability limits,improve combustion efficiency,accelerate flame propagation speed,and reduce pollutant emissions.This paper summarizes the related research at home and abroad in recent years,the main conclusion is that how the microwave plasma affects the turbulence intensity of flow field will be the promising research,and the research trend of microwave plasma ignition and assisted combustion in future will be the research of microwave assisted plasma igniter.

Ultra-fast microwave aided synthesis of gold nanocages and structural maneuver studies

Gold nanocages （AuNcgs） are well-studied, hollow, metallic nanostructures that have fascinated researchers in the fields of nanotechnology, materials science, photoelectronics, biotechnology, and medical science for the last decade. However, the time-consuming synthesis of AuNcgs has limited their widespread use in materials science and nano-biotechnology. A novel, ultra-fast, simple, and highly convenient method for the production of AuNcgs using microwave heating is demonstrated herein. This quick method of AuNcg synthesis requires mild laboratory conditions for large-scale production of AuNcgs. The microwave heating technique offers the advantage of precise mechanical control over the temperature and heating power, even for the shortest reaction period （i.e., seconds）. Microwave-synthesized AuNcgs were compared with conventionally synthesized AuNcgs. Structural maneuver studies employing the conventionally produced AuNcgs revealed the formation of screw dislocations and a shift in the lattice plane. Detailed characterization of the microwave-generated AuNcgs was performed using high resolution transmission electron microscopy （HRTEM）, scanning electron microscopy （SEM）, X-ray powder diffraction （XRD）, and spectroscopic techniques.

Remote Sensing of Tropical Cyclone Thermal Structure from Satellite Microwave Sounding Instruments:Impacts of Optimal Channel Selection on Retrievals

Accurate information on atmospheric temperature of tropical cyclones （TCs） is important for monitoring and pre- diction of their developments and evolution. For hurricanes, temperature anomaly in the upper troposphere can be de-rived from Advanced Microwave Sounding Unit （AMSU） and Advanced Technology Microwave Sounder （ATMS） through either regression-based or variational retrieval algorithms. This study investigates the dependency of TC warm core structure on emission and scattering processes in the forward operator used for radiance computations in temperature retrievals. In particular, the precipitation scattering at ATMS high-frequency channels can significantly change the retrieval outcomes. The simulation results in this study reveal that the brightness temperatures at 183 GHz could be depressed by 30-50 K under cloud ice water path of 1.5 mm, and thus, the temperature structure in hur-ricane atmosphere could be distorted if the ice cloud scattering was inaccurately characterized in the retrieval system. It is found that for Hurricanes Irma, Maria, and Harvey that occurred in 2017, their warm core anomalies retrieved from ATMS temperature sounding channels 4 15 were more reasonable and realistic, compared with the retrievals from all other channel combinations and earlier hurricane simulation results.

A monolithic K-band phase-locked loop for microwave radar application

A monolithic K-band phase-locked loop（PLL） for microwave radar application is proposed and implemented in this paper. By eliminating the tail transistor and using optimized high-Q LC-tank, the proposed voltage-controlled oscillator（VCO） achieves a tuning range of 18.4 to 23.3 GHz and reduced phase noise. Two cascaded current-mode logic（CML） divide-by-two frequency prescalers are implemented to bridge the frequency gap, in which inductor peaking technique is used in the first stage to further boost allowable input frequency.Six-stage TSPC divider chain is used to provide programmable division ratio from 64 to 127, and a second-order passive loop filter with 825 kHz bandwidth is also integrated on-chip to minimize required external components.The proposed PLL needs only approximately 18.2 μs settling time, and achieves a wide tuning range from 18.4 to 23.3 GHz, with a typical output power of –0.84 dBm and phase noise of 91：92 d Bc/Hz @ 1 MHz. The chip is implemented in TSMC 65 nm CMOS process, and occupies an area of 0.56 mm^2 without pads under a 1.2 V single voltage supply.