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In this paper, new single- and dual-band bandpass filters are implemented based on the perturbed multi-mode substrate integrated waveguide (SIW) circular cavity. For the single-band filter, the TM 010 mode, TM 110 A mode, and TM 210 A mode are simultaneously utilized to realize the triple-mode resonance response, of which both the bandwidth and central frequency can be flexibly adjusted by allocating the perturbation position properly. Meanwhile, for the dual-band operation, the TM 010 mode, TM 110 A mode, and TM 210 A mode are arranged to realize the lower passband, whereas the TM 210 B and TM 020 modes are excited to generate the upper passband. The working principle of the filters' coupling topology is explained in detail. For concept verification, both the triple-mode single-band and multi-mode dual-band filters are designed, manufactured and measured, with the measurement results are separately in good agreement with the corresponding simulations. [ABSTRACT FROM AUTHOR]

Aim: Magnetic hydrogels (MHGs) have been proposed to avoid the redistribution and loss of magnetic nanoparticles (MNPs) when administrated by intratumoral injection. However, the requirement of complex cooling systems and temperature monitoring systems still hinder the clinical application of MHGs. This study investigates the feasibility of developing an MHG to realize the self-regulation of hyperthermia temperature. Methods: The MHG was developed by dispersing the MNPs with self-regulating temperature property into the temperature-sensitive hydrogel through physical crosslinking. The MHG's gelation temperature was tested by measuring the storage modulus and loss modulus on a rotational rheometer. The biocompatibility of the MHG and MNPs was characterized by CCK-8 assay against HaCaT cells. The in vivo magnetic heating property was examined through monitoring the temperature in the MHG on mice back upon the application of the alternating magnetic field (400 ± 5 Oe, 100 ± 5 kHz) every week for successive six weeks. Results: The gelation temperature of the MHG falls in 28.4°C-37.4°C. At in vivo applied concentration of 80 mg/mL, the MHG exhibits over 80% cell viability after 72 h, significantly higher than 50% cell viability of the MNPs (p<0.001). The MHG's stable magnetic hyperthermia temperatures in vivo are in the range of 43.4°C–43.8°C. Conclusions: The developed MHG can be injected using a syringe and will solidify upon body temperature. The biocompatibility is improved after the MNPs being made into MHG. The MHG can self-regulate the temperature for six weeks, exhibiting application potential for self-regulating temperature hyperthermia. [ABSTRACT FROM AUTHOR]

Impact of magnetic field distribution on the performance of an 18-vane 5.8 GHz magnetron is studied in this paper. The magnetic field distribution of the magnetron is calculated for the ideal and the real cases. Different from the ideal case, the real magnetic field is non-uniformly distributed in the interaction space. Based on the calculation results, the impacts of the non-uniform magnetic field distribution on the output power, oscillation time, and efficiency of the magnetron are studied by cavity hot-test simulation. The obtained simulation results are verified by experiment. The study provides reference basis for further improving the performance of the magnetron. [ABSTRACT FROM PUBLISHER]

Wheat dried distillers grains with solubles (DDGS) is widely used as a partial replacement for forages or concentrates in ruminant diets. We hypothesised that using exogenous enzymes (ENZ) would increase neutral detergent fibre (NDF) degradability of DDGS. The aims of the study were to (i) evaluate the effects of ENZ and their doses onin vitrogas production (GP) and degradability of wheat DDGS; and (ii) explore possible relationships between the major added enzymic activities and degradation, especially NDF degradation. Three commercially produced ENZ products that provided a range of xylanase, endoglucanase, exoglucanase and protease activities were used. Enzyme activities were assayed under normal rumen conditions with pH 6.0 and temperature 39°C. All three ENZ had a xylanase:endoglucanase ratio of 5:1 to 4:1, but ENZ3 had lower activity per millilitre. ENZ2 had relatively higher exoglucanase activity compared with the other products, with a ratio of xylanase:exoglucanase of 4:1 for ENZ2 compared with 23:1 for ENZ1 and 9:1 for ENZ3. Variable effects of the three ENZ products were observed on GP variables. Degradabilities of dry matter (DM), NDF, acid detergent fibre (ADF) and crude protein (CP) linearly (p < 0.05) increased with increasing ENZ doses, but ENZ1 and ENZ2 exhibited greater (p < 0.05) effects on degradabilities of DM, NDF and ADF compared to the ENZ3. There were positive correlations between added enzymatic activities and degradabilities of DM, NDF and ADF, except for degradability of CP. A multiple regression model analysis showed that xylanase was the main enzymic activity associated with increased degradation of NDF. The results demonstrated the potential of enzyme addition to improve ruminal degradability of wheat DDGS, with xylanase being the main enzymic activity associated with NDF degradability. [ABSTRACT FROM AUTHOR]

Two dinuclear iron(III) compounds, [Fe2(HL1)2(L1)2] · MeOH (1) and [Fe2(μ- )3] (2) [L1 = N-(2-hydroxypropyl)(3-methoxysalicylaldimine) and  = 1,2-bis(2-hydroxybenzylidene) hydrazine], have been synthesized and characterized. Structural analysis of 1 shows that the six-coordinate Fe(III)'s are linked by two alkoxo oxygen atoms from two Schiff-base ligands to form a rectangular arrangement of metal ions and oxygen atoms. The distance of these two Fe(III) ions is 3.2122(8) Å. In 2, three Schiff-base ligands coordinate two Fe(III) ions in a tetradentate mode; each iron is six coordinate with octahedral geometry. The Fe–Fe distance is 3.9304(10) Å. Magnetic susceptibility (2–300 K) indicates an antiferromagnetic interaction between the two oxygen-bridged Fe(III) ions with J = −13.6 cm−1 for 1. [ABSTRACT FROM PUBLISHER]

Based on the sub-gridding scheme, a hybrid method with explicit finite-difference time-domain (FDTD) and implicit Crank-Nicolson (CN) FDTD is presented for ground-penetrating radar (GPR) simulations on dispersive and conductive soils in this paper. The time step of CN-FDTD can be set to a large value so that the whole region can be run with a common time step determined by the coarse grid in a stable fashion. The missing information in the sub-gridded border region is obtained with an interpolation in space. The dispersion of the soil is modeled by a multi-pole Debye model and is solved with auxiliary differential equations (ADEs) for both FDTD and CN-FDTD. Additionally, examples of the GPR scenario are calculated to verify the accuracy and efficiency of the hybrid sub-gridded ADE-FDTD method. [ABSTRACT FROM AUTHOR]

The microwave wireless power transmission system avoids the problems of large consumables, complex construction, and high maintenance costs caused by the cable. It can be seen that this method has specific demands and is worthy of deep research. This paper designs a high-power dual-frequency rectifier circuit that works at 1.15 and 1.7 GHz for wireless energy transmission. Using GaN HEMT as the rectifier, the output DC power reaches 6.5W, far beyond the conventional diode rectifier circuit in terms of power capacity. [ABSTRACT FROM AUTHOR]