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Cast iron with good mechanical and thermal combination property is preferred material for the cylinder head of high power density diesel engine. Interface between graphite and matrix should play a key role in thermal conductivity of cast iron. However, it is difficult to measure the interfacial contact thermal conductance (ICTC) between graphite inclusion and matrix in cast iron. In this paper, a modeling experimental sample containing a macroscopic interface is designed and ICTC can be estimated with the aid of finite element (FE) calculation. At last the effect of ICTC on the thermal conductivity of cast iron is assessed according to the change of metallographic FE simulation results before and after considering ICTC. Results show that the magnitude of ICTC is between 1.0 × 105 and 2.0 × 105 W m−2·K on the whole. The interface makes the theoretical thermal conductivity of cast iron drop down 34.6%. [ABSTRACT FROM AUTHOR]

(Ti, Zn)-co-doped Bi0.97Nd0.03FeO3(BNFTZ) thin films with different thicknesses were prepared directly on indium tin oxide/glass substrates deriving from the precursor solutions with different solution concentrations. The X-ray diffraction, scanning electron microscopy and insulating/ferroelectric/dielectric measurements were utilised to characterise the BNFTZ thin films. Both BNFTZ thin films with the thicknesses of 160 and 320 nm are crystallised into phase-pure perovskite structure without second phase. Compared to the film of 160 nm, a lower leakage current can be obtained in BNFTZ film of 320 nm due to due to its denser microstructure with smaller grain size. The film with 320 nm thickness possesses a high energy-storage efficiency of 87%, which can be ascribed to the slimP–Eloop. At 100 kHz, the film of 320 nm owns lower dielectric constant (~91) and dissipation factor (~0.10). The possible contributions are discussed to explain the difference in the related performances for BNFTZ thin films with different thicknesses. [ABSTRACT FROM AUTHOR]

An infiltration crystallisation concentrating agent was prepared using recycled concrete micropowder from construction waste as main material with instant sodium silicate, aluminium stearate and other active ingredients. The optimum mixture ratio and self-healing effect of the concentrating agent were studied. Compression experiments conducted in the laboratory were terminated when penetrating cracks appeared on the specimen. The specimen was then subjected to standard curing for 28 days after which, second pressure of the specimen was tested. Pore structures of the specimen pre-and post-curing were also tested. The self-healing property of the concentrating agent was characterised using the above comparative analysis. The results indicated that the concentrating agent possessed good self-healing capabilities. The optimum mixture ratio of the self-regenerating infiltration crystallisation concentrating agent is cement, 55%; quartz sand, 25%; instant 5% sodium silicate, 5%; aluminium stearate, 1%; recycled concrete micropowder, 20%; CaO, 8%; water-cement ratio, 0.6 and grey sand ratio, 1/3. [ABSTRACT FROM AUTHOR]

This review outlines the specific methods and concepts of self-healing that have been adopted locally and globally. Based on the need for manual intervention, these methods and concepts of self-healing can be classified as passive or active. The theory of biological self-healing concrete is also analysed. The mechanism by which the diagenesis of biomaterials triggers and promotes self-healing in the tiny cracks of cement is explained. This paper introduces a biological multiple-triggered-switch scheme for the self-healing of cement-based cracks. The role of this mechanism in the continued and feasible self-healing of cracks is analysed. [ABSTRACT FROM AUTHOR]

This paper presents a novel harmonic-suppressed microstrip open-loop resonator bandpass filter with the different transmission line characteristic impedance of the feed line and open-loop resonator for wireless local area network (WLAN) application. To improve the stopband rejection of the filter, the dumbbell-shape defected ground structure (DGS) are applied under the feed lines to suppress the harmonics and the equivalent parameters extraction formulations of double-dumbell-shaped DGSs are the first to proposed. The bandpass filter with center frequency of 2.44 GHz were designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. Measurement results show the filter has a wide stopband characteristic with 30 dB attenuation up to 7.5 GHz and only has an –1.23 dB insertion loss while it is a little larger than the conventional one. The measured results are in good agreement with the simulated results. It can be widely used for WLAN application. [ABSTRACT FROM AUTHOR]

This paper presents a novel harmonic-suppressed microstrip open loop resonator bandpass filter with defected ground structure (DGS) for wireless local area network (WLAN) application. To improve the stopband rejection of the filter, DGSs are applied under the feed lines to suppress the harmonics. The bandpass filter with center frequency of 2.44 GHz is designed and fabricated on a TLX substrate with thickness of 1 mm and dielectric constant of 2.55. By using two dumbbell-shape DGSs the filter has a wide stopband characteristic with attenuation -25 dB up to 8 GHz and has an -1.25 dB insertion loss while it demonstrates a little larger than the conventional one. The measured results agree well with the simulation results. The proposed filter is found to possess low in-band insertion loss and high out-band suppression, making it suitable in WLAN application. [ABSTRACT FROM AUTHOR]

A novel complementary split-ring resonators (CSRRs) DGS has been investigated theoretically and experimentally. The proposed DGS provides excellent performance in terms of double resonant property, ripple in the pass band, sharp selectivity at the cut-off frequency and spurious free wide stop band. A LPF using the proposed DGS unit is fabricated and three cascaded DGSs are employed in another LPF to obtain very wide reject band. The measured results illustrated the excellent performance. [ABSTRACT FROM AUTHOR]

Modified current model has been developed to more accurately model the current-voltage characteristics of GaAs pHEMTs over a wide range of temperature. In particular, the modeling accuracy of knee, saturation and subthreshold regions has been greatly improved. These results are achieved by introducing the polynomial expression on the bias conditions. The verification is performed by fabricated pHEMTs at different temperature. Good agreement is obtained. [ABSTRACT FROM AUTHOR]

A dielectric half space model is introduced into the simulation of the scattering from ships on sea surface, which is excited by a plane wave. With the acceleration of Generalized Forward-Backward (GFB) method, the electromagnetic (EM) scattering can be simulated quickly in high precision. A High Resolution Range Profile (HRRP) is formed with the results computed in half space model, and the HRRP of ship on ocean in different aspects are discussed. As showed in the simulation, the model predicted in the paper is proved more valid and accurate than free space model. [ABSTRACT FROM AUTHOR]

One of the most critical hardware components for the performance of the Ground-Penetrating Radar (GPR) system is the antenna and the resistive loaded antenna is one of common antennas used in the GPR system. The authors extend the Wu-King linear current distribution to the double exponential current distribution, modify the inaccurate part of the Wu-King loading profile and deduce an improved resistive loading profile with high efficiency. The broadband performance of the improved resistive loading profile has been studied; the concept of lengthening coefficient is created and the optimum parameter designing curve of the antenna is provided. Numerical calculation shows that the maximum bandwidth and efficiency of antenna can be achieved with the improved loading profile simultaneously. The impedance bandwidth is as high as 40:1, which is much greater than the 3:1 bandwidth of Wu-King distribution when the voltage standing wave ratio is below 3. It exhibits better efficiency and bandwidth than Wu-King loading profile. The loading profile can reduce the late-time ringing, enhance the pulse radiation characteristics and be widely applied to other resistive loading antenna for GPR applications. [ABSTRACT FROM AUTHOR]

A pair of single chain Fv fragment (scFv) fusion proteins were constructed and characterized. Antibody chips using the pair were designed for sensitive detection of prion protein. Phage displayed antibody library was synthesized by immunizing mice with thioredoxin-mature bovine prion fusion protein (TrxA-bPrPc). After five rounds of panning against recombinant bovine prion protein (rb-PrPc) and ELISA test, two positive clones with high affinity to rb-PrPc, named Z163 and Z186, were obtained. They were conjugated with a linker-streptavidin binding protein (SBP) or human IgG1 constant fragment (Fc) to form the scFv fusion protein pair Z186-L-SBP/Z163-Fc. Western blot experiments showed that the scFv fusion pair specifically interacted with the line epitopes of the protease resistant core region bPrP27-30. Surface plasmon resonance (SPR) sensorgrams revealed that the equilibrium dissociation constants of the interactions with rb-PrPc were 3.24×10-8 M, 8.82×10-8M, and 8.10×10-9 M for Z186-L-SBP, Z163, and Z163-Fc, respectively. All binding reactions followed rapid association and slow dissociation kinetics. As a detection pair, Z186-L-SBP functioned as a capture probe and was immobilized on the streptavidin coated slides to form reactive layer of the antibody chip, and Z163-Fc labeled with fluorescence dye Cy3 functioned as a detection probe generating fluorescence signal. The antibody chip could detect existence of rb-PrPc with detection limit of 1 pg/ml. [ABSTRACT FROM AUTHOR]