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During oven drying of abalone muscle, microwave treatment was conducted at regular time intervals (0, 30, 60, 90 and 120 days). Abalone muscle digestion products (AMDP) were prepared by subjecting dried abalone to in vitro simulated digestion. Our aim was to investigate the effect of microwave treatment during the drying of abalone muscle on the in vitro and in vivo antioxidant activities of AMDP. The results showed that the half maximal inhibitory concentration (IC50) values of AMDP from fresh abalone muscle for scavenging capacity against hydroxyl (·OH) radicals, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) and 1,1-diphenyl-2-phenylhydrazine (DPPH) radical were 3.04, 15.18 and 21.12 mg/mL, respectively. The IC50 values for the scavenging of these three radical species decreased gradually with increasing the drying time of abalone muscle. After being fed AMDP from abalone muscle dried for 120 days, the body length of Caenorhabditis elegans increased from 768.90 to 1 034.62 μm, the head swing frequency increased from 206 to 281 times/min, and the life span was extended by 36.16% under normal conditions and by 59.41% and 38.48% under heat stress and oxidative stress conditions, respectively compared with the control group. Meanwhile, with prolonging the drying time of abalone muscle, the antioxidant enzyme activities, reduced glutathione (GSH) content and total antioxidant capacity of C. elegans fed AMDP increased, and the reactive oxygen species (ROS) content decreased. In summary, prolonging the drying time and using microwave treatment during the drying process could improve the antioxidant capacity of AMDP.

The patterns of changes in the physicochemical properties and volatile flavors of abalone muscle during drying at 50 ℃ and 65% relative humidity were investigated in this study. With an increase in drying time, the browning intensity and fluorescence intensity of both surface and internal muscles of abalone increased gradually, which started to decrease after reaching a peak on the 90th day. The contents of reducing sugar and lysine in the surface muscle were 3.11 mg/g and 2.60% after pretreatment, and decreased to 1.95 mg/g and 1.61% after 120 days of drying, respectively. High molecular mass polymers were observed in the electrophoretic pattern of abalone muscle after 30 days of drying. Fourier transform infrared spectra showed that the intensity of the characteristic absorption peaks (1 403 and 1 026 cm-1) of glycoproteins gradually enhanced with increasing drying time. The response values of the electronic nose sensors W1W (sulfides) and W2S (alcohols, aldehydes and ketones) increased, and the content of 1-octen-3-ol decreased while the contents of linalool and (E,E)-2,4-decadienal increased after 30 days of drying, as determined by gas chromatography-mass spectrometry (GC-MS). At the same drying time, the intensity of Maillard reaction in the surface muscle was weaker than that in the internal muscle.

Based on the Jiles-Atherton model and transducer's structural dynamics principle, the magnetoelastic dynamic strain model of giant magnetostrictive transducer is founded. This model takes into account the eddy current losses and the variety of stress. Simulation results are in a good agreement with the experimental ones. This indicates that the dynamic strain model can characterize the magnetization intensity and strain behavior at different frequency. The proposed model is suitable to describe the relation between the applied field and the output vibration at a wide range of exciting frequency. Index Terms--Bode diagram, dynamic model, eddy current effects, giant magnetostrictive transducer.

According to the hysteresis characteristics of the giant magnetostrictive actuator (MA), a dynamic recurrent neural network (DRNN) is constructed as the inverse hysteresis model of the MA, and an on-line hysteresis compensation control strategy combining the DRNN inverse compensator and a proportional derivative (PD) controller is used for precision position tracking of the MA. Simulation results validate the excellent performances of the proposed strategy. Index Terms--Dynamic recurrent neural network (DRNN), hysteresis, inverse compensator, magnetostrictive actuator (MA).

This paper establishes a simple and novel dynamic hysteresis model for giant magnetostrictive actuator by considering the eddy current loss, anomalous loss and structural dynamic mechanical behavior of the actuator. To obtain parameters of the model, a hybrid genetic algorithm is proposed. Comparisons between the experimental and calculated results show the validity and practicability of the model. Index Terms--Dynamic hysteresis model, hybrid genetic algorithm (HGA), Jiles--Atherton model, magnetostrictive actuator (MA).

The dynamic model with hysteretic nonlinearity for magnetostrictive actuators is developed, combined with Jiles-Atherton model. The simulation and experimental results demonstrate the effectiveness of the model and parameter identification approach.

A non-contact torque sensor based on a magnetostrictive Fe30Co70 rod wound with an excitation coil and a pickup coil is proposed in this paper. In the magnetic field range 0–30 kA/m, the changing rate and linearity of magnetostriction with a loading magnetic field of Fe30Co70 samples are significantly improved after heat treatment. Maximum magnetostriction is 103 ppm in the annealed sample in the parallel direction, while its tensile strength and allowable shear stress are 608 and 194.56 MPa, respectively. According to the mathematical model presented in this work, there is a linear relationship between the output voltage and torque. An apparent increase in the induced voltage signal (peak voltage) of 48.23 mV is observed as the torque increases to 20 Nm in the case of applying sinusoidal excitation signals. In addition, the experimental results are consistent with the calculated values within the torque range 0–16 Nm, and a good sensitivity of 2.87 mV/Nm is obtained. This work shows the prospect of Fe30Co70 alloy for non-contact torque sensing for the appropriate magnetostrictive property with no orientation requirement. [ABSTRACT FROM AUTHOR]