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Novel P(VDF-TrFE)/organosilicate composite membrane was fabricated by electrospinning. The electrospun composite membrane containing as little as 2 wt% of organosilicate demonstrated significant improvements in strength, modulus, and toughness by about 103%, 45%, and 97%, respectively, when compared with those of electrospun pure P(VDF-TrFE) membrane, while maintaining high porosity and good breathability and piezoelectricity. We believe that such an organosilicate-reinforced durable, porous, and piezoelectric P(VDF-TrFE) membrane has huge advantages in various applications such as flexible sensors, wearable electronics, filter membrane, tissue engineering, battery separator, and polymer electrolyte.

Mn-doped 0.7BiFeO3-0.3BaTiO3 (BFO-0.3BTO+Mn 1% mol) lead-free piezoelectric ceramic were fabricated by traditional solid state reaction. The phase structure, microstructure, and ferroelectric properties were investigated. Additionally, lead-free 1–3 composites with 60% volume fraction of BFO-BTO+Mn ceramic were fabricated for ultrasonic transducer applications by a conventional dice-and-fill method. The BFO-BTO+Mn 1-3 composite has a higher electromechanical coupling coefficient (kt = 46.4%) and lower acoustic impedance (Za ~ 18 MRayls) compared with that of the ceramic. Based on this, lead-free piezoelectric ceramic composite, single element ultrasonic transducer with a center frequency of 2.54 MHz has been fabricated and characterized. The single element transducer exhibits good performance with a broad bandwidth of 53%. The insertion loss of the transducer was about 33.5 dB.

A new kind of multiferroic three-ply-structured nanoceramic composites consisting of nanosized alloy-based magnetostrictive (MS) and ferroelectric powders (FE) were fabricated successfully by a conventional solid state reaction in air or argon ambient in our previous investigation. But there are still some problems needed to be solved, for example, the magnetic aging and decrease of saturated magnetization phenomena occurred in samples are perhaps related to the harsh preparation conditions such as storage duration and sintering atmosphere and so forth. In this paper, we will review the characteristics of the novel nanocomposites by means of the microstructure and magnetism existed in the samples with nanosized MS powders (i.e. (Tb0.3Dy0.7)0.75Pr0.25Fe1.55, Sm0.88Nd0.12Fe1.93) as fillers. Also, we hope some reasonable explanations and deeper understandings can be concluded about the proposed ageing and magnetism reduction exhibited when the samples were subjected to co-firing in air or argon ambient. Finally, the potential improvement and multifunctional applications in the future are also suggested.

Fiber-shaped supercapacitor (FSC) is a promising energy storage device for wearable/stretchable electronics by virtue of its unique features such as high flexibility, knittability, small-size and lightweight. However, the energy density of most FSC devices is limited by the relatively low operating voltage. Herein, we develop a solid-state asymmetric fiber-shaped supercapacitor made of carbon fiber thread@polyaniline and functionalized carbon fiber thread electrodes with high operating voltage (1.6 V). The as-prepared device shows a volumetric energy density up to 2 mWh cm−3 which is higher than/compatible to most reported FSCs. The maximum power density of the device is 11 W cm−3, which is comparable to typical commercial supercapacitors. Other than good rate capability, long cycle life and high volumetric capacitance, the proposed device has excellent flexibility. It can be embedded in a glove using a traditional weaving technology without degrading its capacitive performance at various bending conditions. To demonstrate the potential of our supercapacitor for stretchable electronics, we incorporate the device into a conventional elastic thread to form a stretchable supercapacitor. The capacitance of the stretchable device is well maintained even after stretching up to 100%, demonstrating its excellent stretchability. These promising results demonstrate the proposed supercapacitor has great potential as an efficient storage device for flexible and wearable electronics applications.

Recently, high-performance energy storage devices are urgently needed due to the rapid development of miniaturized, portable and wearable electronic equipment. However, most of the single-cell energy storage devices suffer from a relatively low operating voltage. In this work, we present a novel fiber-based micro-asymmetric supercapacitor (ASC) with high performance and good integration ability. A carbon nanoparticle coated carbon fiber (CF@CNPs) is chosen as the substrate owing to its notable features such as high porosity, high flexibility, lightweight, simple processing and ease of integration. A manganese oxide nanosheet grown on CF@CNPs and functionalized CF@CNPs are employed as the positive and negative electrode of the micro-ASC, respectively. The as-prepared ASC device can operate at 1.8 V and exhibit a high volumetric energy density of 2.1 mW h cm−3, which is comparable to that of a thin-film Li-battery. Furthermore, the micro-ASC can achieve a very high capacitance retention of about 82.7% when the charge and discharge current density is changed from 0.25 A cm−3 to 6.3 A cm−3, demonstrating the excellent rate capability of the ASC. The ASC also shows good cycling stability and has great potential for integration with energy harvesting devices to realize highly efficient self-powered systems.

Ordered three-dimensional nanostructures are highly attractive for energy storage application, particularly for high-performance flexible supercapacitors. Here, we report a unique MnO2/Au/MnO2 nanospike (MAMNSP) supercapacitor structure based on free-standing 3-D gold (Au) NSP films. The NSP films are highly flexible and transferable onto an arbitrary flexible substrate to enable applications that require high flexibility. The large surface area of this unique structure leads to a remarkable enhancement in electrochemical performance, 1.9 and 4.26 times higher capacitance as compared with MnO2/Au NSP (MANSP) and MnO2/planar (MAPL) electrodes, respectively. The all-solid-state symmetric supercapacitors based on MAMNSP electrodes have been fabricated and systematic performance characterization showed that the devices have a high volumetric capacitance of 20.35 F cm−3 and a specific energy of 1.75 × 10−3 W h cm−3. In addition, the bendability measurement showed that the supercapacitor devices are highly flexible and reliable. By virtue of simple fabrication procedures and enhanced electrochemical performance, such 3-D structures have highly promising potential for portable and flexible energy storage systems for a wide range of practical applications.

The integration of energy harvesting and energy storage in this device not only enables the conversion of ambient energy into electricity, but also provides a sustainable power source for various electronic devices and systems. It is highly desirable to improve the integration level and minimize unnecessary energy loss in the power-management circuits between energy harvesting and storage devices. In our work, we integrate a PVDF film into a supercapacitor as both the separator and the energy harvester. The double-sides of the polarized PVDF films are coated with H2SO4/poly(vinyl alcohol) (PVA) gel electrolyte. Functionalized carbon cloths are assembled with H2SO4/PVA electrolyte as both anode and cathode, forming a flexible all-solid-state supercapacitor. Externally mechanical impacts establish a piezoelectric potential across the PVDF films, and drive ions in the electrolyte to migrate towards the interface of the supercapacitor electrode, storing the electricity in the form of electrochemical energy. The asymmetric output characteristic of the piezoelectric PVDF film under mechanical impact results in the effective charging of the supercapacitor without any rectification device. The integrated piezo-supercapacitor exhibits a specific capacitance of 357.6 F m−2, a power density of 49.67 mW h m−2, and an energy density of 400 mW m−2. Our hybridized energy harvesting and storage device can be further extended for providing sustainable power source of various types of sensors.

The palladium nanoparticle (Pd NP)-decorated LaAlO3 /SrTiO3 (LAO/STO) heterostructure is for the first time used as a hydrogen-gas sensor with very high sensitivity and workability at room temperature. The outstanding gas-sensing properties are due to the Pd NPs' catalytic effect to different gases, resulting in charge coupling between the gas molecules and the two-dimensional electron gas (2DEG) through the Pd NPs by either a direct charge exchange or a change of the electron affinity. These results provide insight into the emerging properties at LAO/STO interfaces.

Lead-free ceramics (1–x)NaNbO3–xLiTaO3 were synthesized by an ordinary solid-state reaction method. Rietveld analysis reveals that the crystal structure changes from one orthorhombic phase with Pbcm space group to another orthorhombic phase with P2221 space group when increasing x. The morphotropic phase boundary between two different orthorhombic symmetries is formed at 0.14

High photovoltaic efficiency is a key index in the application of silicon (Si) solar cells. In this study, a composite of a photovoltaic Si p–n junction solar cell and a magnetostrictive TbxDy1−xFe2 alloy was fabricated. By utilizing the magnetostrictive strain to modulate the energy bandgap of Si, the open-circuit voltage and the maximum photovoltaic output power of the Si p–n junction solar cell could be enhanced by ∼12% and 9.1% under a dc magnetic field of ∼250 mT, respectively. The significantly enhanced photovoltaic performance and the simple fabrication process make the Si-p–n/TbxDy1−xFe2 composite a promising material for high-efficiency solar cell devices. The structure of the proposed Si-p–n/TbxDy1−xFe2 laminated composite.

We have developed a processing technique for producing cobalt ferrite (CFO)/lead lanthanum zirconate titanate (PLZT) 0-3 composites with enhanced piezoelectric, ferroelectric and magnetoelectrical (ME) coupling properties. It includes modifying the phase boundary with zirconia barrier layer and decreasing the sintering temperature with Li 2 O + 0.5Bi 2 O 3 additives. The CFO/PLZT 0-3 composites were successfully fabricated via conventional co-firing procedures. The obtained 0-3 composite ceramics can withstand a DC electric field of 6 kV mm −1 . The effects of CFO/PLZT ratio on the crystalline structure, piezoelectric, ferroelectric, dielectric and M–E properties were investigated. The M – E coefficients of the composites with CFO:PLZT volume ratio of 14.4:85.6, 27.4:72.6 and 39.3:60.7 were found to be 31, 52 and 143 mV (Oe cm) −1 at 100 kHz under a bias field of ∼1 kOe.

A magnetostrictive/piezoelectric drum magnetoelectric transducer has been fabricated for H2 detection. Due to the difference in the acoustic wave velocity for H2 (1284 m/s) and air (331 m/s), the resonance frequency of the magnetoelectric coupling effect will shift when H2 gas enters the drum cavity filled with air. A good linear relationship between the resonance frequency shift (Δf) and the volume fraction of H2 (n%) is observed. The resolution on the H2 volume fraction of our magnetoelectric drum detector was experimentally observed as ∼0.25%. The detection coefficient (Δf/n) for H2 volume fraction of our ME drum transducer is approximately equal to ∼0.48 kHz. The magnetoelectric drum is hopeful for H2 physical detection.

Organic–inorganic hybrid solar cells based on poly(3-hexylthiophene) and electrospun TiO2 nanofibers were fabricated by solution process. The efficiency of the device was improved by modifying CdS nanoparticles on the surface of TiO2 by electrochemical method. The CdS layer can lead to the increase of both open circuit voltage and short circuit current of the device, which are attributed to enhanced exciton dissociation and light absorption and suppressed carrier recombination by CdS at the heterojunction. However, too thick CdS layer led to increased series resistance and decreased efficiency of the device. Therefore, the optimum condition of the CdS deposition was obtained, which increased the power conversion efficiency of the device for about 50%. Our results indicate that the surface modification on the inorganic semiconductor layer is an effect way to improve the performance of the hybrid solar cells.

Endoscopic ultrasound radial array transducers were fabricated using PZT ceramic tubes by a rotate-and-dice method. 50-element 14 MHz and 100-element 3 MHz radial array transducers have been fabricated and characterized with a pulse-echo response measurement. It was found that both transducers exhibit reasonably good performance. The −6 dB bandwidth of these two array transducers was found to be 46% and 56%, respectively. Besides, the insertion loss of the transducers was found to be 26 dB and 32 dB, respectively. The results show that the rotate-and-dice method is an effective way to fabricate radial array transducers for various applications.

In this work, we show that light intensity modulation can be realized in the system of one-dimensional time-variant photonic crystals. Difierent from conventional light modulators, the functioning of the proposed structure emphasizes on its spatial/temporal structures instead of inherent material properties. Additionally, our system can perform inherent light modulation without introducing external stimuli, thus avoiding direct contacts with electrodes (or other modulation sources), which would be preferable in certain environments. The in∞uences of parameters such as light frequency, structure dimensions, and refractive index contrasts on the modulation performance of the time-variant photonic crystal were investigated by numerical simulations. The results provide a new strategy for light modulation, which may add functionalities in optical communication, integrated-optics or display technologies.

High frequency (≥20 MHz) phased-array ultrasound transducers exhibit many benefits in biomedical applications. However, high performance array transducers, with high resolution and high sensitivity, are hard to fabricate due to the limitation of their rigorous dimensions. In this study, to achieve a high −6 dB bandwidth, a 20-MHz 64-elements phased-array transducer based on a PMN-0.3PT single crystal as an active layer has been fabricated using a photolithography method. High piezoelectric properties of PMN-0.3PT, such as high electromechanical coupling coefficients and high piezoelectric constants, lead the transducer to exhibit a −6 dB bandwidth of ∼90% and an insertion loss of 29 dB in the pulse-echo measurement. The results show a great enhancement on the performance when comparing with those reported 20-MHz array transducers based on piezoelectric single crystal and ceramic materials.

In this study, a 20-MHz 64-element phased-array ultrasound transducer with a one-wavelength pitch is developed using a PMN-30%PT single crystal and double-matching layer scheme. High piezoelectric ( d 33 > 1000 pC/N) and electromechanical coupling ( k 33 > 0.8) properties of the single crystal with an optimized fabrication process involving the photolithography technique have been demonstrated to be suitable for wide-bandwidth (⩾70%) and high-sensitivity (insertion loss ⩽30 dB) phased-array transducer application. A −6 dB bandwidth of 91% and an insertion loss of 29 dB for the 20-MHz 64-element phased-array transducer were achieved. This result shows that the bandwidth is improved comparing with the investigated high-frequency (⩾20 MHz) ultrasound transducers using piezoelectric ceramic and single crystal materials. It shows that this phased-array transducer has potential to improve the resolution of biomedical imaging, theoretically. Based on the hypothesis of resolution improvement, this phased-array transducer is capable for small animal (i.e. mouse and zebrafish) studies.

We introduce a simple and effective method to deposit a highly uniform and semitransparent MnO2 film without coffee-ring effect (CRE) by adding ethanol into MnO2 ink for transparent capacitive energy storage devices. By carefully controlling the amount of ethanol added in the MnO2 droplet, we could significantly reduce the CRE and thus improve the film uniformity. The electrochemical properties of supercapacitor (SC) devices using semitransparent MnO2 film electrodes with or without CRE were measured and compared. The SC device without CRE shows a superior capacitance, high rate capability, and lower contact resistance. The CRE-free device could achieve a considerable volumetric capacitance of 112.2 F cm(-3), resulting in a high volumetric energy density and power density of 10 mWh cm(-3) and 8.6 W cm(-3), respectively. For practical consideration, both flexible SC and large-area rigid SC devices were fabricated to demonstrate their potential for flexible transparent electronic application and capacitive energy-storage window application. Moreover, a solar-powered energy storage window which consists of a commercial solar cell and our studied semitransparent MnO2-film-based SCs was assembled. These SCs could be charged by the solar cell and light up a light emitting diode (LED), demonstrating their potential for self-powered systems and energy-efficient buildings.

In this work, lead-free 1–3 composites based on piezoelectric 0.947Na0.5Bi0.5TiO3–0.053BaTiO3 (NBT–0.053BT) single crystal and epoxy are fabricated for ultrasonic transducer applications by a modified dice-and-fill method. Excellent properties for ultrasonic transducer applications have been achieved, such as high electromechanical coupling coefficient (kt = 73%), lower acoustic impedance (Z = 16 MRayl) and moderate dielectric constant. Based on this lead-free piezoelectric single crystal composite, single-element ultrasonic transducer and linear array have been fabricated and characterized. Both types of transducers exhibit similar performance with broad bandwidth of exceeding 100%. The promising results show that these lead-free composites have the potential to be used for high-performance ultrasonic transducers.

In this work, we show how to manipulate the electromag- netic wave at will by using an indeflnite medium with extremely strong anisotropy. The negative element in the indeflnite permittivity tensor goes to the negative inflnity while the positive element is equal to 1, which stretches the hyperbolic equifrequency contour into a straight line type. The direction of the Poynting vector and the wave vector is aligned by the straight line type equifrequency contour along the orientation of the extremely negative permittivity, thus control the wave propagation. The other permittivity of 1 makes the indeflnite medium matched with the air. Moreover, because of the hyperbolic equifrequency contour, evanescent wave can also transmit in the indef- inite medium under the propagation mode, implying the possibility of controlling an evanescent wave by this special indeflnite medium. Sim- ulations are performed to demonstrate the controlling performance and a potential design to realize such a medium by metamaterial with mul- tilayered metal/dielectric structure. This work may supply a shortcut for those former devices based on the Transformation optics.

Bismuth-modified potassium sodium niobate K 0.48 Na 0.52 Nb 1− x Bi x O 3 ( x = 0.05–0.15) transparent lead-free ceramics were fabricated by a hot-pressing method. Both hot-pressing conditions (pressure, temperature and duration) and Bi-content were found to have strong influences on the density, transparency, electro-optical coefficient, and electrical properties of the ceramics. Under the typical hot-pressing conditions of 1060 °C for 5 h at 5.5 MPa, the optimum Bi-content was found at 7.5 at.% in the system under study. These ceramics display good optical transmission in the visible and particularly in the infrared regions. For visible light, the highest transmission value of a polished 0.5-mm thick plates is about 60% at a wavelength of 800 nm; while for infrared, the transmission value is about 80% at 4000 nm. The effective linear electro-optic coefficient of the ceramics was found to be 42 pV m −1 . The dielectric permittivity and loss tangent of the KNNB ( x = 0.075) ceramics were found to be 716 and 0.031 at room temperature.

A new three-ply structured multiferroic Sm 0.88 Nd 0.12 Fe 1.93 –Pb(Zr 0.53 Ti 0.47 )O 3 (MS-PZT) ceramic composite has been developed successfully by cofiring at 900 °C under argon atmosphere via a solid solution process. The magnetic and polarization hysteresis loops prove the coexistence of the ferromagnetic and ferroelectric phases in the composites. TEM images show the alloy particles were dispersed uniformly and mainly located at the PZT grain boundaries. The DC resistivity as high as 10 9 –10 10 Ω.cm was obtained and only varies slightly with the volume fraction of the conductive phase Sm 0.88 Nd 0.12 Fe 1.93 . The composites can be poled under a high electric field strength at a temperature of 150–180 °C. The dielectric, piezoelectric, and magnetic properties of the composites can be tailored according to the desirable requirement to meet designated application by a simple, flexible, and reproducible route, providing a promising potential approach to a new class of electric circuit and significant miniaturization of devices.

We report on the integration of a PMN-PT single crystal-based piezoelectric resonator in a microfluidic system. In this experiment, the resonator was implanted in the microfluidic channel through a standard soft lithography process with its top electrode in contact with the flowing fluid. The results showed that, activated in shear mode, the resonator sensed changes occurring along the fluid-electrode interface and gave responses in the form of impedance resonance frequency shift. By measuring the frequency shift, changes in the fluidic property (e.g. viscosity) could be monitored. Examples are given to demonstrate the potential use of the system for cell detections.

通过溶胶-凝胶工艺在CoFe 2 O 4 (简称CFO)粉体表面包覆二氧化锆陶瓷层来阻挡烧结过程中铁磁相与铁电相之间的离子扩散. 包覆后的CFO与0.92(Bi 0.5 Na 0.5 )TiO3-0.02(Bi 0.5 K 0.5 )TO 3 -0.06BaTiO 3 (简称BNBT) 陶瓷粉体分别按照 x CFO/(1- x ) BNKLABT (质量分数 x = 0.05、0.10、0.15、0.20、0.25、0.30)混合均匀, 并用聚乙烯醇为粘结剂模压成圆片; 再经过1050℃烧结制备了铁磁/铁电0-3型复合材料. XRD分析表明: 二氧化锆在高温烧结过程中对离子扩散具有良好的阻挡作用. 复合陶瓷的耐击穿电压大于75kV/cm. 测量结果表明: 复合陶瓷的压电应变常数、机电耦合系数、介电常数和剩余极化随CFO含量的增加而降低; 磁电耦合系数、介电损耗随CFO含量的增加而有所增大. -35mm×1.5mm的复合陶瓷样品( x =0.05)在谐振频率(90kHz)和199kA/m 偏置磁场下的磁电系数为1.39V/A.

Fine-grained Pb(Zr 0.53 Ti 0.47 )O 3 –(Ni 0.5 Zn 0.5 )Fe 2 O 4 (PZT–NZFO) magnetoelectric (ME) composite ceramics were fabricated by a modified hybrid process at a low sintering temperature of 900 °C. Well-controlled crystallized grain size and homogeneous microstructure with a good mixture of two phases were observed in the ceramics. The ceramics show coexistence of ferrimagnetic and ferroelectric phases with well-formed ferromagnetic and ferroelectric hysteresis loops at room temperature. A significant ME effect was observed with a ME coefficient of 0.537 V cm −1 Oe −1 in the vicinity of electromechanical resonance. In addition, high capacitance can be obtained at low frequency, and magnetic properties in the ceramics can be tailored by the grain size of the ferromagnetic particles in a simple and flexible way.

The study of single cell dynamics has been greatly adapted in biological and medical research and applications. In this work a novel microfluidic electrochemical sensor with carbon nanotubes (CNTs) modified indium tin oxide (ITO) microelectrode was developed for single cells release monitoring. The sensitivity of the electrochemical sensor after CNTs surface modification was improved by 2.5–3 orders of magnitude. The developed CNTs modified ITO sensor was successfully employed to monitor the dopamine release from single living rat pheochromocytoma (PC 12) cells. Its ultrahigh sensitivity, transparency and need for fewer agents enable this smart electrochemical sensor to become a powerful tool in recording dynamic release from various living tissues and organs optically and electrically.

Hybrids of graphene oxide (GO) nanosheets and surface-modified Fe 3 O 4 nanoparticles (NPs) were fabricated by a two-step process. First, Fe 3 O 4 was modified by tetraethyl orthosilicate and (3-aminopropyl) triethoxysilane to introduce amino groups on its surface. Second, the amino groups of Fe 3 O 4 were reacted with the carboxylic groups of GO with the aid of 1-ethyl-3-(3-dimethyaminopropyl)carbodiimide and N -hydroxysuccinnimide to form a GO–Fe 3 O 4 hybrid. The attachment of Fe 3 O 4 NPs on the GO nanosheet surface was confirmed by transmission electron microscopy and Fourier-transform infrared spectroscopy. The adsorption capacity of GO–Fe 3 O 4 for methylene blue and neutral red cationic dyes was as high as 190.14 and 140.79 mg/g, respectively. The GO–Fe 3 O 4 hybrids could be reduced to form graphene–Fe 3 O 4 hybrids by using NaBH 4 as reducing agent and be used to prepare magnetic GO films.

Damping behavior with an oscillating bending force applied to each of the three different crystallographic planes a – b , a – c , and c – a is measured in a tetragonal ferromagnetic shape memory Ni 50 Mn 29 Ga 21 single crystal at different combinations of frequency and temperature by a dynamic mechanical analysis method. The results show a frequency-independent anisotropic damping behavior in the martensitic phase with a loss factor of 0.03, a high loss factor of 0.15, and an ultrahigh loss factor of 0.26 for the a – b , a – c , and c – a crystallographic planes, respectively. The observed anisotropic damping behavior is found to originate from the reorientation of different numbers of martensitic twin variants upon bending. It is also adjustable by an applied magnetic field via the control of the martensitic twin-variant bending states.

Magnetoelectric (ME) effect is observed in a bilayered composite fabricated by laminating one ferromagnetic shape memory Ni–Mn–Ga single-crystal plate with one piezoelectric PVDF polymer film. The reported ME effect originates from the mechanically mediated magnetic field-induced strain effect in the Ni–Mn–Ga plate and piezoelectric effect in the PVDF film. The induced ME voltage shows a good linear response to the applied ac magnetic field in the field range of 0–5 Oe. A large ME coefficient ( α E ) of 1.24 V/(cm Oe) is obtained at an optimal bias magnetic field of 5.1 kOe due to the reversible reorientation of martensitic twin variants in the Ni–Mn–Ga plate. Based on the combination of pseudo-piezomagnetism in the Ni–Mn–Ga plate and piezoelectricity in the PVDF film, the ME effect in the bilayered composite is predicted and found to agree with the experimental results.

Electromyography (EMG) and ultrasonography have been widely used for skeletal muscle assessment. Recently, it has been demonstrated that the muscle thickness change collected by ultrasound during contraction, namely sonomyography (SMG), can also be used for assessment of muscles and has the potential for prosthetic control. In this study, the performances of one-dimensional sonomyography (1D SMG) and surface EMG (SEMG) signal in tracking the guided patterns of wrist extension were evaluated and compared, and the potential of 1D SMG for skeletal muscle assessment and prosthetic control was investigated. Sixteen adult normal subjects including eight males and eight females participated in the experiment. The subject was instructed to perform the wrist extension under the guidance of displayed sinusoidal, square and triangular waveforms at movement rates of 20, 30, 50 cycles per min. SMG and SEMG root mean squares (RMS) were collected from the extensor carpi radialis, respectively, and their RMS errors in relation to the guiding signals were calculated and compared. It was found that the mean RMS tracking errors of SMG under different movement rates were 18.9% +/- 2.6% (mean+/-SD), 18.3% +/- 4.5%, and 17.0% +/- 3.4% for sinusoidal, square and triangular guiding waveforms, while the corresponding values for SEMG were 30.3% +/- 0.4%, 29.0% +/- 2.7% and 24.7% +/- 0.7%, respectively. Paired t test showed that the RMS errors of SMG tracking were significantly smaller than those of SEMG. Significant differences in RMS tracking errors of SMG among the three movement rates (p

Dense, homogeneous, and fine-grained multiferroic BaTiO 3 /(Ni 0.5 Zn 0.5 )Fe 2 O 4 composite ceramics are synthesized by a novel powder-in-sol precursor hybrid processing route. This route includes the dispersion of nanosized BaTiO 3 ferroelectric powders prepared via conventional sold-state ceramic process into (Ni 0.5 Zn 0.5 )Fe 2 O 4 ferromagnetic sol–gel precursor prepared via sol–gel wet chemistry process. Uniformly distributed slurry is obtained after ball milling and used in the fabrication of the ceramics with low sintering temperatures. The ceramics show coexistence of ferromagnetic and ferroelectric phases with obvious ferromagnetic and ferroelectric hysteresis loops at room temperature, besides exhibiting excellent magnetic and dielectric properties in a wide range of frequency. The combination of high permeability and permittivity with low losses in the ceramics enables significant miniaturization of electronic devices based on the ceramics.

Different Power types and parameters in the electrodeposition process result in different microstructures and hence mechanical properties. In this paper, direct current and double pulse power with different combinations of on and off time have been used for electrodeposition. The tensile properties of the electrodeposited (Ed) Cu with different parameters in process have been studied and also the microstructures of the Cu obtained have been examined by SEM. This paper aims at explaining the effects of one of the important parameters in electrodeposition: different power types on the tensile properties. The tensile properties of Ed Cu after Surface Mechanical Attrition Treatment (SMAT) are also shown in this paper.

This paper presents the latest development of a lead-free piezoelectric ceramic and its application to transducers suitable for high-frequency ultrasonic imaging. A lead-free piezoelectric ceramic with formula of (K(0.5)Na(0.5))(0.97)Li(0.03)(Nb(0.9) Ta(0.1))O(3) (abbreviated as KNLNT-0.03/0.10) was fabricated and characterized. The material was found to have a clamped dielectric constant epsilon(33)(S)/epsilon(0)=890, piezoelectric coefficient d(33)=245 pC/N, electromechanical coupling factor k(t)=0.42 and Curie temperature T(c)300 degrees C. High-frequency (40 MHz) ultrasound transducers were successfully fabricated with the lead-free material. A representative lead-free transducer had a bandwidth of 45%, two-way insertion loss of -18 dB. This performance is comparable to reported performances of popular lead-based transducers. The comparison results suggest that the lead-free piezoelectric material may serve as an alternative to lead-based piezoelectric materials for high-frequency ultrasonic transducer applications.