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This paper proposes a Chinese medical question answering system based on CNN s with self-attention embedded model. The key idea of the proposed framework is first understanding whole sentences via LSTM, obtaining the feature map by the convolution layer of CNN, then further-comprehending of question and answer by self-attention and finally pass through to polling layer of CNN to enhance accuracy. In addition, due to the word segmentation issue in the Chinese especially in medical field, character embedding is applied to enhance the accuracy. The experimental results show that the proposed framework improves the accuracy around 80%.

Switch-capacitor battery equalizer (SCBE) is widely used because of its simple structure, small PCB area, and no inductance components. Its balance current is sawtooth or trapezoid waveform is significantly different from traditional charger’s DC waveform. From many non-DC charging literatures, it can be found that different frequency and waveform shape will cause the significantly different battery charging performance. Therefore, this paper explores the near-optimal balance current frequency and waveform shape of the SCBE from electrochemical impedance to optimize its battery balance performance. Further, the LC resonant battery equalizer (LC-RBE) is proposed to perform battery balancing with a sine wave. Experiments have shown that the better efficiency and lower battery temperature rise are obtained when the LC-RBE work with the battery minimum ac impedance frequency.

A progressing non-toxic plasma-enhanced solid Se vapor selenization process (PESVS) technique, compared with hydrogen-assisted Se vapor selenization (HASVS) to achieve a large-area (30×40 cm2) Cu(In,Ga)Se2 (CIGS) solar panel with enhanced efficiencies from 10.8% to 13.2% (14.7% for active area), was demonstrated. The bonding of Se was partially broken by ICP plasma treatment and these Se radicals are helpful to enhance reaction activity for following selenization process at an extremely low temperature of 330 °C. The effects of plasma steps, plasma power, selenization temperature and optimized conditions were thoroughly studied in detail. The remarkable enhancement of the efficiency is ascribed to the better crystallinity, enlarged grain size, less Se vacancy and uniform depth distribution of Ga. From reaction kinetics point of view, PESVS provides extra energy to crack Se, resulting in the decrease in reaction activation energy. The PESVS methodology was also applied to low temperature (450 °C) selenized CIGS thin film solar panel with uniform conversion efficiency more than ~10%. Furthermore, a large-area flexible stainless steel substrate with remarkable conversion efficiency of ~6.8% without Na addition was demonstrated. We believed that this work can provide a facile approach of low temperature selenization on flexible substrate applications or fast selenization for throughput consideration, thus stimulating the mass-production in large scale CIGS PV industry.

We report on the fabrication of a robust and flexible transparent electrode to replace costly and fragile indium tin oxide (ITO) used in flexible Cu(In,Ga)Se2 solar cells, composed of an aluminum doped zinc oxide (AZO)/Ag-nanowires/aluminum doped zinc oxide (AZO) (AAA herein) sandwich structure. The Ag-NWs networks form low-resistance, long-range pathways throughout the electrode that are able to maintain efficient charge carrier collection and extraction after strenuous mechanical bending. The improved durability of the AAA electrode enables our CIGS solar cells to maintain ∼95% of their initial power conversion efficiency, following 1000 bending cycles. In comparison, devices fabricated using AZO and ITO electrodes are only able to maintain ∼57 and ∼5%, respectively, due to crack formation and delamination of the films. This AAA sandwich structure electrode could therefore serve as a high-performance electrode for numerous flexible optoelectronic applications.

In this work, enhanced broadband solar spectrum absorption and solar-thermal conversion efficiency (~ 8%) has realized and reported by Au-decorated CuInS 2 nanoparticles, namely Au@CIS NPs. The morphologies, compositions and absorptions were characterized by high resolution transmission electron microscopy (HR-TEM), UV–vis spectrometer and Finite-Difference Time-Domain (FDTD) numeric methods. The Au@CIS NPs shows a distinguished absorption perfectly matching AM1.5 G solar spectrum, compared with pure Au, CIS and CIS–Au mixture nanoparticles (NPs) owing to near field plasmonic-assisted effect. In addition, the Au@CIS NPs proves its practical applications on selective distillation in non-polar solvent systems, for which the selective distillation of methylcyclohexane from toluene as an example was demonstrated. The approach can evoke future developments of plasmonic-assisted heterostructure in nanoscale for thermal solar energy harvesting application.

A reactive mold-assisted chemical etching (MACE) process through an easy-to-make agarose stamp soaked in bromine methanol etchant to rapidly imprint larger area micro- and nanoarrays on CIGS substrates was demonstrated. Interestingly, by using the agarose stamp during the MACE process with and without additive containing oil and triton, CIGS microdome and microhole arrays can be formed on the CIGS substrate. Detailed formation mechanisms of microstructures and the chemical composition variation after the etching process were investigated. In addition, various microand nanostructures were also demonstrated by this universal approach. The microstructure arrays integrated into standard CIGS solar cells with thinner thickness can still achieve an efficiency of 11.22%, yielding an enhanced efficiency of ∼18% compared with that of their planar counterpart due to an excellent absorption behavior confirmed by the simulation results, which opens up a promising way for the realization of high-efficiency micro- or nanostructured thin-film solar cells. Finally, the complete dissolution of agarose stamp into hot water demonstrates an environmentally friendly method by the mold-assisted chemical etching process through an easy-to-make agarose stamp.

A facile wet soaking process by immersing a CIGS thin film in a mixed aqueous solution, containing gallium trichloride and thioacetamide at 80 °C for a few tens of seconds, was proposed to reduce the existence of defects in the CIGS absorption layer which can be confirmed by the temperature dependence of the open-circuit voltage (Voc). The depth profiles of X-ray photoelectron spectroscopy (XPS) results indicate that the gallium (Ga) concentration increases during the short wet soaking time, resulting in a widening of the band gap near the surface region. The enhanced carrier lifetime attributed to the Ga-induced defect reduction during thermal treatment of device fabrication was evaluated by time-resolved photoluminescence (TRPL) spectroscopy. With wet and light soaking processes, Voc, short circuit current (Jsc) and fill factor (F.F.) can be increased, yielding a significant enhancement in cell efficiency from ∼1% to ∼6.4%. We believe that this fast, simple and effective method can further stimulate the development of CBD-Zn(O,S)/post-selenization CIGS solar cells toward commercialized thin film photovoltaics.

The electromechanical characteristics of PVDF are investigated, including the crystallization, frequency responses, hysteresis, leakage currents, current-voltage characteristics, and fatigue characteristics using X-ray diffraction and an electrometer. Results show that the frequency band of PVDF increases with increasing resistive load and capacitance. The hysteresis area of ΔH slightly increases with increasing input voltage. The magnitude of the current values increases with decreasing delay time at a given drive voltage. PVDF film induced larger degradation when the number of stress cycles was increased to about 105 cumulative cycles.

Johnson (1970) obtained expansions for marginal posterior distributions through Taylor expansions. Here, the posterior expansion is expressed in terms of the likelihood and the prior together with their derivatives. Recently, Weng (2010) used a version of Stein's identity to derive a Bayesian Edgeworth expansion, expressed by posterior moments. Since the pivots used in these two articles are the same, it is of interest to compare these two expansions. We found that our O(t −1/2) term agrees with Johnson's arithmetically, but the O(t −1) term does not. The simulations confirmed this finding and revealed that our O(t −1) term gives better performance than Johnson's.

The leakage and fatigue characteristics of polyvinylidene fluoride (PVDF) are investigated for flexible electronics. The crystallization, frequency responses, leakage currents, current-voltage characteristics, and fatigue characteristics of PVDF film are measured using X-ray diffraction and an electrometer. Results show that a PVDF model with a resistive load exhibits high-pass filter characteristics. The frequency band of PVDF film increases with increasing resistive load and capacitance. The break frequencies for 100 kΩ, 300 kΩ, 700 kΩ, and 1 MΩ at the break frequency are 611, 207, 88, and 61 Hz, respectively. The hysteresis area of ΔH slightly increases with increasing input voltage. The leakage current of PVDF film is higher for a lower delay time under a given applied electric field. The average leakage currents for delay times of 10 and 1000 ms are 0.565 and 73.8 pA, respectively. The magnitude of the current values increases with decreasing delay time at a given drive voltage. PVDF film induced larger degradation when the number of stress cycles was increased to about 105 cumulative cycles.

The interaction of poor water-soluble drug loratadine (LOR) with β-cyclodextrin (β-CD) or hydroxypropyl-β-cyclodextrin (HP-β-CD) in aqueous or solid state was investigated. Mechanical grinding effect on the inclusion steps, thermodynamic kinetics and inclusion efficiency of inclusion complex formation of LOR with β-CD or HP-β-CD was quantitatively investigated by DSC and FT-IR microspectroscopy with curve-fitting analysis. The phase solubility profiles of LOR with β-CD and HP-β-CD were classified as AL-type phase diagram. The grinding-induced reduction in LOR crystallinity in the presence of β-CD or HP-β-CD was found to be apparent zero-order kinetics. The inclusion efficiency of solid inclusion complex for LOR/β-CD or LOR/HP-β-CD was significantly correlated with the reduction in LOR crystallinity and the grinding time. The mechanism of inclusion complex formation for LOR/β-CD or LOR/HP-β-CD was proposed through the progressive reduction in LOR crystallinity, the promoted LOR amorphization, and molecular inclusion processes in the continuous energy input process of mechanical grinding.

Fabrication, nanoindentation characteristics, and optical spectroscopy of patterned ITO for multi-touch panel are investigated. The fabrications were carried out in two parts. The first part fabricates the high/low impedances of ITO patterns on silicon wafer, and the second part sputters the ITO patterns on PET film using MEMS fabrication. The array strips of ITOs on the PET film are defined as contact areas and row electrodes of scanning lines. The ITO patterns on the glass substrate include the contact areas, the narrow wires for high impedance, and the column electrodes of scanning lines for low impedance. The nanoindentation characteristics of load-unload regions generated elastic energy dissipation, which is attributed to higher elastic response, frictional energy, stiffness, and compressive plastic deformation. The maximum transmittance is 74.2% at the wavelength of about 692 nm due to a thicker ITO and Al films.

The thermal stability and thermodynamics of gabapentin (GBP) in the solid state were investigated by DSC and TG techniques, and FTIR microspectroscopy. The detailed intramolecular lactamization process of GBP to form gabapentin-lactam (GBP-L) was also determined by thermal FTIR microspectroscopy. GBP exhibited a DSC endothermic peak at 169 °C. The weight loss in TG curve of GBP suggested that the evaporation process of water liberated via intramolecular lactamization was simultaneously combined with the evaporation process of GBP-L having a DSC endothermic peak at 91 °C. A thermal FTIR microspectroscopy clearly evidenced the IR spectra at 3350 cm−1 for water liberated and at 1701 cm−1 for lactam structure formed due to the lactam formation of GBP. This study indicates that the activation energy for combined processes of intramolecular lactamization of GBP and evaporation of GBP-L was about 114.3 ± 23.3 kJ/mol, but for the evaporation of GBP-L alone was 76.2 ± 1.5 kJ/mol. A powerful simultaneous DSC–FTIR combined technique was easily used to quickly examine the detailed kinetic processes of intramolecular cyclization of GPB and evaporation of GBP-L in the solid state.

The use of costly and rare metals such as indium and gallium in Cu(In,Ga)Se2 (CIGS) based solar cells has motivated research into the use of Cu2ZnSnS4 (CZTS) as a suitable replacement due to its non-toxicity, abundance of compositional elements and excellent optical properties (1.5 eV direct band gap and absorption coefficient of ~104 cm−1). In this study, we demonstrate a one-step pulsed hybrid electrodeposition method (PHED), which combines electrophoretic and electroplating deposition to deposit uniform CZTS thin-films. Through careful analysis and optimization, we are able to demonstrate CZTS solar cells with the VOC, JSC, FF and η of 350 mV, 3.90 mA/cm2, 0.43 and 0.59%, respectively.

Defect control in Cu(In,Ga)Se2 (CIGS) materials, no matter what the defect type or density, is a significant issue, correlating directly to PV performance. These defects act as recombination centers and can be briefly categorized into interface recombination and Shockley–Read–Hall (SRH) recombination, both of which can lead to reduced PV performance. Here, we introduce an electrochemical passivation treatment for CIGS films that can lower the oxygen concentration at the CIGS surface as observed by X-ray photoelectron spectrometer analysis. Temperature-dependent J–V characteristics of CIGS solar cells reveal that interface recombination is suppressed and an improved rollover condition can be achieved following our electrochemical treatment. As a result, the surface defects are passivated, and the power conversion efficiency performance of the solar cell devices can be enhanced from 4.73 to 7.75%.

Mesoporous SBA-15 silica materials functionalized with and without carboxylic acid groups were used to effectively control the morphology of Pt crystals, and the materials thus obtained were applied to methanol oxidation reactions. The Pt particles aggregated to form long spheroids inside the channels in pure SBA-15. When carboxylic acid groups were utilized, the SBA-15(-COOH) material facilitated the formation of higher Pt surface area, smaller Pt nanoparticles and nearly spherical shape due to the strong interaction between Pt(4+) ions and carboxylic acid on SBA-15. The Pt(4+) ions on the SBA-15(-COOH) material can be directly transformed to reduced Pt particles during calcination. The methanol oxidation activity on a Pt surface is strongly dependent on the shape of Pt particles. The near-spherical Pt nanoparticles on the SBA-15(-COOH) exhibited higher catalytic activity during methanol oxidation than Pt catalysts on unmodified SBA-15. The near-spherical Pt particles on the SBA-15(-COOH) contained large numbers of terrace sites on their surfaces, which led to high efficiency during methanol oxidation.

Cyclodextrins (CDs) have been considerably raised interest and attention in the pharmaceutical sciences due to their specific ability to form inclusion complexes with many drugs, leading to significant enhancements of the solubility, stability and bioavailability, as well as decrease in the bitterness and tissue irritation of the drugs (Carrier et al., 2007; Challa et al., 2005; Miller et al., 2007). Thus, CDs have been extensively applied to the pharmaceutical dosage form development for various drugs. Up-to-date, over 30 CDcontaining drug products have been commercialized on the global pharmaceutical market for clinical use (Davis & Brewster, 2004; Loftsson & Brewster, 2010).

The purpose of this study was to investigate the milling effect on the polymorphic transformation of four gabapentin (GBP) Forms I-IV in the absence of additive. Four polymorphs of GBP were previously prepared and identified, in which the GBP Form I was proven to be a monohydrate, but other GBP Forms II-IV belonged to anhydrate. The GBP Form II was the most stable polymorph available in the market. The co-milling process affecting the polymorphic stability of GBP Form II with different additives was also examined. During the 120-min-milling or co-milling course, the milled sample was withdrawn at prescribed intervals for Fourier transform infrared (FTIR) microspectroscopic determination. In the absence of additive, each polymorph of GBP exhibits a different polymorphic transformation behavior in the 120-min-milling course. The results indicate that GBP Form I was previously dehydrated and transited to Form II; GBP Form II was first transformed to Form III and then changed to Form IV; GBP Form III was previously transited to Form II, then changed to Form III and transformed to Form IV at last; whereas GBP Form IV was first changed to Form II, then transited to Form III and finally to Form IV. It was clearly evidenced that if GBP Form III or IV appeared in the milled mixture a little amount of GBP-lactam was certainly detected. In the presence of additives, there was almost lack of polymorphic transition for GBP Form II by co-milling GBP Form II with Emcompress, beta-cyclodextrin, mannitol, corn starch or magnesium stearate. By co-milling GBP Form II with Avicel, dextrin, hydroxypropyl beta-cyclodextrin, hydroxypropyl methylcellulose, Kollidon K-30 or gelatin, GBP Form II was transformed to Form IV alone. On the other hand, the GBP Form IV and a little amount of GBP-lactam were also found in the co-milled mixture after co-milling with GBP Form II with Aerosil or talc. This reveals that the solid-state transformation of GBP Form II after co-milling was markedly dependent on the types of additive used.

Purpose. The aim of this study was to determine the progressive processes of polymorphic transformation of different gabapentin (GBP) polymorphs by using hot-stage Fourier transform infrared (FTIR) microspectroscopy. Methods. Four polymorphs of GBP were previously prepared and then identified by differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, FTIR microspectroscopy and X-ray powder diffractometry. A novel hot-stage FTIR microspectroscopic technique was used to investigate the progressive steps of polymorphic transformation of each GBP polymorph sealed within two pieces of KBr plates. Results. Four polymorphs (Forms I, II, III and IV) of GBP were well characterized. The GBP form I was proven to be a monohydrate, but other GBP forms II-IV were anhydrous. Different thermal-induced progressive processes and steps of polymorphic interconversion of GBP polymorphs were clearly found from the changes in the three-dimensional IR spectral contour and peak intensity by using hot-stage FTIR microspectroscopy. The results also indicate that GBP form I was dehydrated and transformed to form III, and then converted to form IV; whereas GBP forms II and III directly transformed to form IV during heating. The GBP form IV was the last polymorph before the intramolecular lactamization of GBP. Conclusion. A one-step novel hot-stage FTIR microspectroscopy was successfully applied to simultaneously and continuously investigate the progressive processes and steps of thermal-induced polymorphic interconversion of GBP polymorph in the solid state.