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Concrete encased CFST (CECFST) column is a composite member consisted of outer encased concrete and inner CFST. Currently, a cast-in-place connection between a CECFST column and a reinforcement concrete beam is generally employed in engineering practice due to the outer encased concrete hinders the application of assembled connection, and the steel beam is usually connected to the CECFST column by on-site welding. In this paper, a novel on-site assembled connection between a CECFST column and a steel beam was proposed. In considering various material models and complex contacts, a FE model for this type of joint was established and verified. Further, parametric analyses of the assembled connections to concrete encased CFST columns were conducted to analyze the structural behavior. More importantly, an extended component model was developed to cover the feature of CECFST column focusing on the initial stiffness and moment resistance of the assembled connection. The load transfer mechanism for bolt in tension and beam flange in compression were considered in the modelling for evaluating the stiffness and strength of column wall in tension and in compression, respectively. The numerical results from the parametric analyses coincided well with the predicted results. The numerical and analytical results declared that this novel assembled connection between the CECFST column and steel beam performed favorable structural behavior and could be employed in assembled structures with CECFST columns.

In this paper, a broadband closed-form expression for the parasitic inductance of Through-X Vias (TXVs) with a frequency up to 100 GHz is proposed. The rigorous formulas related to the geometrical parameters are derived considering the proximity effect and the skin effect. The proposed model can accurately reflect the change in inductance caused by magnetic flux variation at high frequency. The inductance model is verified by comparing with the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS) in whole frequency range considered. The proposed model and HFSS results show accordance with each other over large radius range, with a maximum error of 4.6%.

An analytic model of the tapered differential through glass vias is proposed in this paper. Each expression accounting for the via length, diameter, slope angle and pitch is derived from basic physics and the IMD layer is included, additionally. The RLGC equivalent circuit is verified by comparing the S-parameters resulted from the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS) and Advanced Design System (ADS). The feature selective validation (FSV) technique is used to as a measure of the comparisons. The proposed model and HFSS results show accordance with each other up to 20 GHz The excellent transmission characteristics of glass substrate reflect from S-parameters, of which the S21 is about the order of magnitude of 10−3 dB and the S11 is lower than −30 dB till 20 GHz. Moreover, the impact of different configuration on transmission coefficient is investigated.

By utilizing coaxial through-silicon via (TSV) technology, compact L C low-pass filters (LPFs) are proposed. Firstly, several capacitors based on coaxial TSV are investigated, in detail, by means of analytic calculation, finite element method (FEM) simulation, and measurement. Secondly, a formula for the inductance of coaxial TSV-based spiral inductors is proposed and verified by FEM simulations and measurements. Finally, based on the investigation of TSV-based capacitors and inductors, an analytical model of the proposed L C LPFs based on 2 × 4 , 2 × 5 , 2 × 6, and 2 × 7 coaxial TSV arrays is proposed, and the equivalent circuit model and the finite element method (FEM) model are established in ADS and HFSS, respectively. The LPFs are fabricated and verified through measurements. In the proposed LPFs, coaxial TSVs are used as capacitors and inductors simultaneously, which leads to a more compact size. The parasitic capacitance of the inductors can, helpfully, induce a notch point for the proposed LPFs in stopband and improve the roll-off rate.

Accurate detection of mutiple biomarkers in unprocessed blood via lateral flow immunoassay (LFA) strips remains challenging. Herein, we reported a novel surface-enhanced Raman scattering (SERS)-based LFA strip for ultrasensitive and simultaneous analysis of dual infection biomarkers by using functionalized Fe3O4@Au magnetic nanoparticles (MNPs). Antibody-modified Fe3O4@Au MNPs were designed as SERS nanotags and efficient enrichment tool. The target infection biomarkers were quickly captured and enriched from the blood sample by Fe3O4@Au nanotags. After washing to remove impurities, Fe3O4@Au nanotags acted as high-performance SERS reporters for quantitative detection of the target in the LFA strip. Through this strategy, the proposed Fe3O4@Au based LFA allowed quantified analysis of target infection biomarkers in unprocessed blood samples with the limits of detection of 0.1 ng/mL and 0.01 ng/mL for serum amyloid A (SAA) and C-reactive protein (CRP), respectively. By comparison, the proposed assay for SAA and CRP was 100-fold and 1000-fold more sensitive than standard colloidal gold strip by using the same antibodies, respectively. This magnetic SERS strip also exhibited excellent stability, specificity, and selectivity for complex samples and could be used as an effective tool for infectious disease diagnostics.

A physics based close form inductance model for three-dimensional (3-D) solenoid inductors with ground shileding is proposed in this letter. The expressions are derived in full consideration of partial self inductance and mutual inductance. The proposed model is extracted based on the process parameters and design parameters without any optimization. The 3-D inductor samples are fabricated on glass substrate by Through Glass Via (TGV) process. The accuracy of the proposed model is validated by comparing the results from the 3-D full-wave electromagnetic solver High Frequency Simulator Structure (HFSS) and measurement.

Unbonded prestressed reinforced concrete column (UBPRC column) has become an attractive approach in the field of bridge seismic design due to its superior self-centering behavior. Unbonded prestressing bar in a UBPRC column functions as a self-centering element and longitudinal mild reinforcement functions as an energy dissipator. Quasi-static cyclic test was carried out in this study to compare the seismic performance of reinforced concrete column (RC column), UBPRC column and fully prestressed concrete column (FPC column). The result shows that the UBPRC column has higher post-yield stiffness and smaller quasi-static residual displacement, but lower energy dissipation capability than the RC column. The FPC column suffers from the least quasi-static residual displacement, but has the lowest energy dissipation capability, the least ultimate displacement and the most severe prestress loss. The quasi-static residual displacement and residual crack width of the UBPRC column are around 66% and 73% of those of the RC column, respectively. The failure patterns of the RC column and the UBPRC column are similar, while the failure pattern of the FPC column is similar to that of a rocking column. The self-centering behavior of the three columns was analyzed and quantified using a self-centering index, which can be recommended for use in the seismic design of bridge columns.

Crossover phenomena are ubiquitous in disordered system. However, the crossover effects from the competition between different fixed points make it hard to identify the asymptotic scaling regime controlled by the random fixed point. Therefore, the analyses on the crossover effects are of great importance to understand phase transition in dilute magnetic materials. In this paper, we derive the scaling function characterizing the crossovers to probe critical behavior. According to these, we show an alternative method to locate the asymptotic critical region in the quenched random systems in the finite-time dynamics frame. For the three-dimensional bond-diluted Ising model, the asymptotic critical exponents are identified with ν = 0.686 ( 1 ) , β = 0.356 ( 6 ) , α = − 0.057 ( 3 ) , γ = 1.345 ( 20 ) , z = 2.170 ( 11 ) at middle bond concentration p = 0.7 from the effective ones describing the approach to the asymptotic regime for weak dilution ( p = 0.9 ) and strong dilution ( p = 0.5 ). The dynamic critical exponent from our non-equilibrium simulation supports distinctly z ≈ 2.18 as suggested previously, as opposed to the existing larger values.

In this paper, closed-form expression for the parasitic capacitance of tapered TSV (T-TSV) considering metal-oxide-semiconductor (MOS) effect is proposed by solving two-dimensional (2D) Poisson's equation. ANSYS Q3D Extractor is employed to verify the proposed model for the slope wall angle of 75^o, 80^o, 85^o and 90^o. It is shown that error is less than ~5%. The capacitance characterization of copper T-TSV is studied in detail, by taking slope wall angle of 80^o for instance. The results show that the capacitance of T-TSV acts as that of MOS device in changing the bias voltage; the increases of the bottom radius of T-TSV (from 1 to [email protected]), dielectric liner thickness (from 0.1 to [email protected]), liner dielectric constant (from 1 to 5), T-TSV height (from 10 to [email protected]) and acceptor concentration (from 1x10^1^5 to 5x10^1^5cm^-^3) cause increase of T-TSV capacitance by about 25fF, -12fF, 12fF, 210fF and 12fF, respectively. Finally, the condition for T-TSV simplified to cylindrical TSV is obtained.

In this paper, a facile electrochemical alloying–dealloying technique was performed in aqueous media to prepare a nanoporous platinum (Pt) electrode with high sensitivity for glucose sensing. A homogeneous Pt–Cu alloy was electrochemically deposited on a glassy carbon electrode at room temperature, and then Cu in the alloy was selectively dissolved by electrochemical method from the Pt–Cu alloy resulting in the nanoporous platinum film with a higher surface area. A roughness factor of the electrode was determined from the ratio of the true area to the geometric area, and it was up to 184. This nanoporous platinum exhibits high stability and remarkable catalytic activity for glucose oxidation in pH 7.0 PBS. It is also resistant toward poisoning by some common interfering species such as uric acid and p-acetamidophenol. Under the optimal experimental conditions, the nanoporous platinum film responded to glucose with a good linear dependence in the range from 1.00 × 10 −5 to 8.14 × 10 −3 M and the detection limit was 7.75 × 10 −6 M (S/N = 3).