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Q1 highly stable, water-based barium titanate BaTiO3, BT, sol was synthesized using a sol–gel route through a chelate lactate technique. Dried BT precursor powders were measured by thermal gravimetry–differential thermal analysis and X-ray diffraction. It was found that BT powders first converted into barium carbonate BaCO3, Ti complex, and intermediate phase Ba2Ti2O5CO3, and then transformed into perovskite phase BaTiO3. The crystallization temperature was about 5501C. The low-voltage etched aluminum foils were covered with BT sol by dip coating, and then annealed at 6001C for 30 min in air. After that, the samples were anodized in a 15 wt% aqueous solution of ammonium adipate. The voltage–time variations during anodizing were monitored, and the electrical properties of the anodic oxide film were examined. It was shown that the specific capacitance, the product of specific capacitance and withstanding voltage, and leakage current of samples with a BT coating were about 48.93%, 38.50%, and 167% larger than that without a BT coating, respectively.

We employed differential scanning calorimetry and X-ray powder diffraction to determine the effect of tea polysaccharide (TPS) and carboxymethyl cellulose (CMC) on the gelatinization and retrogradation behavior of wheat starch (WS) gels. The total WS concentration of the gels was 35 wt%; WS/polysaccharide mixing ratios were 10/0, 9.9/0.1, 9.8/0.2, 9.7/0.3, 9.6/0.4, and 9.5/0.5. As the polysaccharide level was increased, the onset temperature, conclusion temperature and enthalpy of starch melting also increased. Samples blended with CMC exhibited higher gelatinization parameters than TPS mixtures at the same concentration. Upon reheating the starch samples after storage at 4 °C, we found that the glass transition temperature and retrogradation ratio decreased with increasing polysaccharide ratio and increased with the duration of storage. As the concentration of polysaccharide was increased, the endothermic enthalpy gradually decreased for the WS/TPS system and slightly increased for WS/CMC. After 20 days of storage at 4 °C, the degree of crystallization in the WS/TPS system was significantly lower than in the WS/CMC system. Avrima equation analysis revealed that the retrogradation rate of the control was eight times higher than samples containing 5% TPS and two times higher than samples containing 5% CMC. The overall results demonstrated that the inhibitory effect of TPS was greater than that of CMC under the same conditions.

A water-based bismuth titanate Bi 4 Ti 3 O 12 (BTO) sol was synthesized by mixing bismuth nitrate, tetra- n -butyl titanate, lactic acid, acetic acid and distilled water. The sol was applied to low-voltage etched aluminum foil by dip-coating. The crystallization process of Bi 4 Ti 3 O 12 on low-voltage etched aluminum foil was measured by thermal gravimetry–differential scanning calorimetry (TG–DSC) and high-temperature X-ray diffraction (HT-XRD). It was found that Bi 4 Ti 3 O 12 sol first converted into intermediate phase Bi 1.74 Ti 2 O 6.624 , then transformed into perovskite phase Bi 4 Ti 3 O 12 . After annealed at 600 °C for 30 min in air, the low-voltage etched aluminum foil covered with Bi 4 Ti 3 O 12 sol was anodized galvanostatically in 15 wt.% ammonium adipate solution. The voltage–time variation during anodizing was monitored and recorded. The structure and composition of samples were investigated by field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray analysis (EDAX). Results showed that the anodic composite oxide film was composed of an inner Al 2 O 3 layer and an outer Bi 4 Ti 3 O 12 layer. The specific capacitance and the product of specific capacitance and withstanding voltage of samples with a BTO coating were about 56.64% and 43.77% larger than that without a BTO coating.

The molecular structures of starches from Pueraria lobata (Willd.) Ohwi were examined and compared with those of other tuberous and root starches. The fresh tubers were collected from three Chinese main Pueraria lobata (Willd.) Ohwi growing regions. The chain distributions of the amylopectins as determined by gel permeation chromatography were similar to those of the amylopectins of other starches. Among the three amylopectins studied, the respective β-amylolysis limits were 55%, 56% and 58% which were similar to that of kuzu amylopectin. The number average degree of polymerization () values of the amylopectins were 8.7-9.7×103, lower than those of sweet potato and potato amylopectins (9.9×103 and 11.2×103, respectively). The number of branch chains per amylose molecule was 5.0. The average chain length () of the Pueraria lobata (Willd.) Ohwi amyloses was similar to those of kuzu (310), sweet potato (310) and tapioca amyloses (340), but lower than those of lily (475) and potato (670).

Barium titanate BaTiO3 (BT) sol was dip-coated on the etched aluminum foils by a sol–gel process. After annealed at 600 °C in air, the foils were anodized in ammonium adipate solution. The voltage–time variations during anodizing were monitored. The structure, composition, and electric properties of the anodic foils were investigated. The obtained foils were fabricated into aluminum electrolytic capacitors and the load and shelf life test were measured. It was found that the slope of the voltage–time curve of aluminum foil covered with BT films became steeper. A triple layer of Al/Al2O3/BT was formed after anodizing Al/BT foil. The specific capacitance and the product of specific capacitance and withstanding voltage of anodic foil with a BT coating were about 46.36% and 38.90% larger than that without a BT coating. After the load life and shelf life of 2500 h at 85 °C, two kinds of capacitors have similar behaviores and meet with Nichicon standard of Japan. From the results, BaTiO3 is promising to be used as the dielectric of aluminum electrolytic capacitor to increase the specific capacitance.

The homogenous coating of poly (3,4-ethylenedioxythiophene) (PEDOT) on carbon nanotubes was realized by using functionalization of single-walled carbon nanotubes (SWNTs) in this study. Consequently, the PEDOT/functionalized SWNTs (PEDOT/F-SWNTs) composites, with size of around 100nm, which is much smaller than that of PEDOT, were prepared by the electrochemical method. Its small granule increased the active/nonactive mass ratio and reduced the ions diffusion length. Therefore, its specific capacitance of the composite was up to 200F g−1, which was remarkably greater than that of PEDOT. Furthermore, the PEDOT/F-SWNTs composites had very rapid charge/discharge ability with specific capacitance of 180F g−1 at scanning rate of 200mV s−1 and 170F g−1 at frequency of 1Hz, which is an important practical advantage. In addition, such composite had a good cycling performance and a wide potential window.

A highly stable, reproducible and water-based bismuth titanate (BTO) sol system has been synthesized by an aqueous sol–gel method. First bismuth nitrate was dissolved in acetic acid, and then it was mixed with a solution of lactic acid dissolved tetra-n-butyl titanate, subsequently, water was added to adjust sol concentration. As-obtained sols or gels were characterized by Ultraviolet–Visible Spectrophotometer, derivative differential thermal analysis-differential thermal analysis–thermal gravimetry, in situ Raman, and high-temperature X-ray diffraction. Results show that the BTO sol can remain stable for more than 1 year and BTO can start to crystallize at about 450°C.

Conducting polypyrrole (PPy) films doped with p-toluenesulfonate (TOS−), ClO4−, and Cl− were electrochemically prepared, respectively. The electrochemical capacitance properties of the PPy films were investigated with cyclic voltammetry (CV), galvanostatical charge/discharge, and electrochemical impedance spectroscope (EIS) techniques. The morphology observation and structure analysis of PPy films were performed by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that PPy-Cl and PPy-TOS were characterized with a highly porous and ordered structure, which led to their fast ion switch processes. Moreover, they exhibited a rectangle-like shape of voltammetry characteristics even at a scanning rate of 50 mV·s−1, a linear variation of the voltage with respect to time in the charge/discharge process, and almost ideal capacitance behavior in low frequency, even in deeply charged/discharged states in 1 mol·L−1 KCl solution. Furthermore, specific capacitance of PPy-Cl (polymerization charge of 2 mAh·cm−2) could reach 270 F·g−1 (scanning rate of 5 mV·s−1) or 175 F·g−1 (scanning rate of 200 mV·s−1) and its specific energy could reach 35.3 mWh·g−1. Moreover, with heavier doping ion (TOS−), PPy-TOS (polymerization charge of 2 mAh·cm−2) had a slightly smaller specific capacitance (146 F·g−1, scanning rate of 5 mV·s−1), but a very rapidly charge/discharge ability (specific capacitance of 123.6 F·g−1 at scanning rate of 200 mV·s−1) and its specific power could reach 10 W·g−1. In addition, both PPy-TOS and PPy-Cl had good cycleability. All of the above implied that the PPy-Cl and PPy-TOS were two kinds of promising electrode material for supercapacitors.

Poly (3,4-ethylenedioxythiophene)/polypyrrole composite electrodes were prepared by electropolymerization of 3,4-ethylenedioxythiophene (EDOT) on the surface of polypyrrole (PPy) modified tantalum electrodes. The morphology observation of PPy and poly(3,4-ethylenedioxythiophene)/polypyrrole composite (PEDOT/PPy) was performed on Field Emission Scanning Electron Microscope (SEM). The electrochemical capacitance properties of the composite were investigated with cyclic voltammetry (CV), galvanostatic charge–discharge and electrochemical impedance spectroscopy (EIS) techniques in the two- or three-electrode cell system. The results show that the PEDOT/h-PPy (PPy with horn-like structure) composite films were characterized with highly porous structure, which leads to their specific capacitance as 230 Fg −1 in 1 M LiClO 4 aqueous solutions and even 290 Fg −1 in 1 M KCl aqueous solutions. Moreover, the composite exhibits a rectangle-like shape of voltammetry characteristics even at scanning rate 100 mV s −1 , a linear variation of the voltage with respect to time without a clear ohm-drop phenomenon in galvanostatic charge–discharge process and almost ideal capacitance behavior in low-frequency in 1 M KCl solutions. Furthermore, specific power of the composite would reach 13 kW kg −1 and it had good cycle stability. All of the above imply that the PEDOT/h-PPy composites were an ideal electrode material of supercapacitor.

Polypyrrole-film was formed successfully onto LiMn2O4 electrode by electrochemical polymerization, as a new method to improve cycling performance of LiMn2O4 cathode, which was quite different from cation doping and surface coating of LiMn2O4. Both of pure electrode and modified electrode were characterized by X-ray diffraction and electrochemical techniques. The XRD patterns demonstrated that crystallized polypyrrole was deposited onto the LiMn2O4 electrode. The charge-discharge tests revealed that modified electrode by polypyrrole-film had an excellent rechargeability, 98.2% of the initial discharge capacity and 90.1% of the 13th discharge capacity at C/3 rate in the voltage range of 3.5-4.3V after 150 cycles, but for pure electrode, only 53.4% of the initial discharge capacity. The CV curves showed that the new method was very efficient for restraining capacity fade of LiMn2O4, in fair agreement with the charge-discharge test. The EIS measurements in a frequency range from 100kHz to 1mHz were conducted on the electrodes. It was exhibited that the presence of polypyrrole-film decreased the charge transfer resistance and facilitated the charge-transfer reaction in the LiMn2O4 material, which is favorable for improving performance of LiMn2O4 cathode. 1 Corresponding author: ylxu@mail.xjtu.edu.cn, Tel:0086-29-82665161, mp:0086-13991815083

Background Most postsurgical macroreentry atrial tachycardias (PS-MATs) are atriotomy related; however, underlying mechanisms and prevention remain undefined. Objective The purpose of the present study was to investigate the electrophysiological and histologic bases of right atriotomy incision arrhythmogenicity and whether a modified atriotomy that extends the incisional line to the tricuspid annulus (TA) and inferior vena cava (IVC) prevents PS-MAT. Methods Atrial arrhythmia induction and electrophysiological and histologic characteristics were studied 8 weeks after right atriotomy in 30 adult swine according to incision distance to TA or IVC (groups A, B, and C: broad, narrow, and closed corridors, respectively; group D, no-incision sham; n=6 per group, except n=12 for group B). Results Sustained PS-MATs were induced and mapped in the broad- and narrow-corridor groups (A, 1 of 6 [16.7%] vs B, 5 of 12 [41.7%]) but not in the closed-corridor (C) or sham (D) groups ( P = .087). With 20-ms pacing cycle–length decrements (from 350 to 270 ms), mean conduction time over 20 mm at the atriotomy-to-TA corridor was 29.2 ± 2.2, 31.0 ± 4.2, 26.0 ± 1.9, and 17.0 ± 1.4 ms for 5 and 10 mm (both group B), 15 mm (group A), and sham incision ( P = .017), respectively. Conduction properties correlated with histologic findings: the wider the corridor, the healthier its tissue. In group C (modified atriotomy), both corridors were replaced by dense scar with complete conduction block. Conclusion Atriotomy corridor width determines conduction properties and contributes to arrhythmogenicity. A modified right atriotomy that extends to the TA and IVC prevents PS-MAT.

Miniaturization and light weight of aluminum electrolytic capacitor can be achieved via the enhancement in the specific capacitance of anodized aluminum foils resulted from the introduction of compounds with high permittivity into dielectric layer. However, the electrostatic repulsion between the compounds and aluminum substrates hinders this introduction of the compounds, leading to a limited improvement in the specific capacitance. In this work, a novel strategy has been developed to promote the deposition of TiO2 on the surface of aluminum foils by surface modification with polyvinyl alcohol, which sharply decreases the electrostatic repulsion and dramatically increases the mass of deposited TiO2. The evolution of composition and morphology during the process are studied and the capacitor performance of aluminum foils with various treatments is investigated. Interestingly, after surface modification, a specific capacitance of 131.5 µF cm−2 under the withstanding voltage of 21.2 V is obtained, and there is about 60% enhancement in the specific capacitance compared with those without TiO2, and about 30% enhancement compared with those without surface modification, respectively. The specific capacitance obtained is the highest one for aluminum electrolytic capacitor reported to date. These outstanding performances exhibit great potential of this strategy for commercial application on aluminum electrolytic capacitor.

Titanium dioxide (TiO2) is usually introduced into dielectric layer of aluminum electrolytic capacitor to enhance capacitance performance via forming Al2O3-TiO2 composite film. However, there is a big obstacle caused by high crystallization temperature of TiO2 to capacitance enhancement. In present work, a facile route was proposed to synthesize crystalline TiO2 with the size of 3-10 nm at room temperature using lactic acid (LA) and acetylacetone (Acac) as double chelators. After being introduced into the surface of etched aluminum foils as dielectric layer, TiO2 boosted the specific capacitance by about 24% compared to that without TiO2, and about 11% compared to that with TiO2 using lactic acid as only chelator.

Polyaniline (PANI) with high crystallinity degree was facilely synthesized on the surface of stainless steel net by galvanostatic method. The effect of polymerization current density on the characteristics of morphology and structure had been investigated by field emission scanning electron microscopy (FE-SEM), Fourier transforms infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). FE-SEM observations disclosed that PANI was deposited as nanofibers and their diameters decreased with the polymerization current density. FTIR studies revealed that degree of oxidation increased in order PANI-2

Using pulsed laser deposition, TiO2 (-) B and its recently discovered variant Ca:TiO2 (-) B (CaTi5O11) are synthesized as highly crystalline thin films for the first time by a completely water-free process. Significant enhancement in the Li-ion battery performance is achieved by manipulating the crystal orientation of the films, used as anodes, with a demonstration of extraordinary structural stability under extreme conditions.

The profile and bioactivity of phytochemicals in Araiostegia yunnanensis (Christ) Cop were investigated. The total flavonoids content in A. yunnanensis is about 84.90 mg/g. By means of HPLC-DAD-ESI-MS, the main flavonoids in A. yunnanensis were tentatively identified as myricetin 3-O-rhamnosylglucoside, eriodictyol 7-O-rutinoside, quercetin 3-O-rutinoside, luteolin-7-O-apiosylglucoside, quercetin 3-O-rhamnosylgalactoside, and luteolin 7-O-glucoside. The extract (0.268 mg/ml total flavonoids) from A. yunnanensis showed very strong superoxide anion radical scavenging potential and reducing power, which are higher than those of rutin (0.25 mg/ml). The extract (0.268 mg/ml total flavonoids) from A. yunnanensis exhibited similar DPPH scavenging activity with rutin (0.25 mg/ml). However, rutin (0.25 mg/ml) showed a significantly higher ABTS radical scavenging effect than that of the extract (0.268 mg/ml total flavonoids) from A. yunnanensis. The methanol extract from A. yunnanensis showed obviously cytotoxic effects on A549 cells and it had no effect against acetylcholinesterase.

Starch-graft-sodium acrylate (St-g-SA) copolymers were synthesized with ammonium persulfate as an initiator. This work focused on the effects of amylose content of corn starch on the water absorbent capacity and microstructure of the St-g-SA copolymers. The water absorbent capacity of waxy, maize and high amylose St-g-SA copolymers was 1800 g/g, 1300 g/g and 1100 g/g respectively. The grafted copolymers were characterized by FTIR and solid state 13C NMR confirming that the graft reaction had taken place between sodium acrylate and corn starch. The surfaces and cross sections of St-g-SA copolymers were observed by SEM. Incomplete gelatinized starch aggregates increased with increasing amylose content on surfaces and cross sections of copolymers, which accorded with the water absorbent capacity and grafting ratio. DMTA results showed that the waxy St-g-SA copolymer had the highest transition temperature which indicated waxy starch had high grafting ratio.

Background Bronchofiberscopy, a widely used procedure for the diagnosis of various pulmonary diseases within intensive care units, has a history of association with nosocomial infections. Between September and November 2009, an outbreak caused by multidrug-resistant Acinetobacter baumannii (MDR-Ab) was observed in the intensive care unit of a tertiary care hospital in Beijing, China. This study is aimed to describe the course and control of this outbreak and investigate the related risk factors. Methods Clinical and environmental sampling, genotyping with repetitive extragenic palindromic polymerase chain reaction (REP-PCR), and case–control risk factor analysis were performed in the current study. Results During the epidemic period, 12 patients were infected or colonized with MDR-Ab. Sixteen (72.7%) of twenty-two MDR-Ab isolates from the 12 patients and 22 (84.6%) of 26 MDR-Ab isolates from the bronchofiberscope and the healthcare-associated environment were clustered significantly into a major clone (outbreak MDR-Ab strain) by REP-PCR typing. Seven patients carrying the outbreak MDR-Ab strain were defined as the cases. Six of the seven cases (83%) received bronchofiberscopy versus four of the 19 controls (21%) (odds ratio, 22.5; 95% confidence interval, 2.07–244.84; P = 0.005). Several potential administrative and technical problems existed in bronchofiberscope reprocessing. Conclusions Bronchofiberscopy was associated with this MDR-Ab outbreak. Infection control precautions including appropriate bronchofiberscope reprocessing and environmental decontamination should be strengthened.

The independent component analysis and wavelet transform technology are used to separate and identify the internal combustion engine noise signal. According to the basic principle of independent component analysis, FastICA based on negative entropy great with the good stability and convergence speed algorithm is applied to separate the noise signals of six cylinder diesel engine. And the noise signals are decomposed into a series of independent components. The fast Fourier transform and wavelet transform technology are applied on each independent component analysis. Combining with the time-frequency analysis results and the internal combustion engine noise signal spectrum and the structure of the separation of the independent component and getting the corresponding relationship of different internal combustion engine noise sources. The results show that: the independent components correspond to the diesel engine combustion noise sources, the piston knock noise, and fuel injection pump noise and so on.

This paper is based on the software product for DengFeng city cement plant and DengFeng ZhongLian cement Limited company. This software system consists of server-side software, client-side software and handheld programmer software. Key technologies used in system contain non-contact IC card and car license recognition etc. The paper elaborated system requirements. Software functions and software implement processes of server-side, client-side and handheld programmer are all analyzed too.

To resolve the question: penetrate firewall and accurately identify the remote host operating system, research deeply on the ARP protocol and the TCP/IP protocol stack, provide a mothed about host detection through firewall, describes the TCP port scanning process, design a fingerprint storehouse, TCP bag first part and operating system detecting process, develop the network security assessment system based on this way. Test results show that this system can penetrate firewall and accurately identify the target host operating system.

The purpose of this study was to explore further the functions of konjac glucomannan (KGM) in starch-based foods. Experiments were carried out using the mixed amylose/amylopectin/KGM system as a model. High-speed differential scanning calorimetry (hyper-DSC) with the support of high-performance size exclusion chromatography (HPSEC) equipped with multi-angle laser light scattering (MALLS) and differential refractive index (RI), X-ray diffractometry (XRD) and viscosimetry was used to investigate the effects of KGM on glass transition temperatures (T(g) s) of mixtures with different amylose/amylopectin ratios.Hyper-DSC results showed that the T(g) s of amylose, amylopection and their mixtures decreased with increasing concentration of KGM. Based on the molecular characteristics of KGM, HPSEC-MALLS-RI, viscosimetry and XRD results showed that the molar masses of KGM ranged from 1.023 × 10(6) to 1.329 × 10(6) g mol(-1) ; the root mean square (RMS) radii were distributed from 110.5 to 129.6 nm, and M(w) /M(n) was 1.017. KGM was a linear molecule with random-coil conformation in solution and the crystallinity was 0.00%.It is suggested that the addition of KGM has plasticizing effects on the structures of amylose and amylopectin, which can increase free volume and molecular movement of amylose and amylopectin chains, resulting in a decrease in their T(g) s.

Non-homogeneous Poisson Process (NHPP) model with typical reliability growth patterns is an important technology about evaluating software reliability. Two parameters which affect software reliability are original failures number and failure-detected rate. The paper firstly defines the software failure distributed and discusses a few kinds' software reliability models. Non-homogeneous Poisson process model is presented. The models with different parameters are discussed and analyzed. The model's restrict condition and some of parameters, original failures number and failure-detected ratio, are extrapolated. Assessment methodology about key parameters is given.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

A new hermetic seal package using silicon cap has been developed for MEMS devices. This package method was combined with fabrication of MEMS device, which utilized bulk silicon micromachining and bonding technology. The anodic bonding between the silicon cap and the glass substrate on which the MEMS device stand was performed to package the devices. Before the bonding package, a thermal oxide silicon layer was grown to acquire insulation between the silicon cap and the metal lines on glass substrate. A Z-axis accelerometer using this package method has been successfully demonstrated in a 4-inch FAB. The influence on the accelerometer performance of the package method was examined. The testing results showed the hermeticity was satisfied with the requirements of resonant or inertial sensors, and the sensitivity of the accelerometer was about 16fFg/sub -1/.

Spinel LiMn2O4 is one of the cathode active materials for the rechargeable lithium-ion batteries with the most potential, but suffers from a fast capacity fade when cycling at elevated temperatures (55 °C). Spinel LiMn1.97Ti0.03O4 coated with aluminum nitrate is heat-treated at various temperatures. The sample treated at low temperature (500 °C) exhibits porous Al2O3 layer coated on the surface, and little Al ion diffusing into the spinel structure. As for the sample treated at mid-temperature (700 °C), it exhibits double layers coated on the surface: the inner layer is LiAlxMn1.97−xTi0.03O4 solid solution and the outer layer is compact Al2O3 metal oxides. When the heat-treatment temperature increases to a high level (850 °C), nearly all the Al ion diffusing into the structure to form Al doped solid solution layer coated on the spinel. The relationship between the structure of the modified samples and their electrochemical properties is investigated. The galvanostatic charge–discharge results show that those surface-modified samples exhibit improved cycling performance compared to LiMn1.97Ti0.03O4; and the sample treated at mid-temperature delivers the best capacity retention, especially at 55 °C. The improved cycling performance is ascribed to the coated layers of Al2O3 and LiAlxMn1.97−xTi0.03O4 on the spinel particles. The Al2O3 layer could reduce the HF damage by scavenging of HF. While the LiAlxMn1.97−xTi0.03O4 layer could enhance the stability of the spinel structure due to the stronger Al–O bond; moreover, this coating layer having the same spinel structure with the LiMn1.97Ti0.03O4 core material would not hinder the lithium ion diffusion. The sample treated at mid-temperature has the double layers coated on the surface, and its Al2O3 coating becomes compact and thin which could effectively block the direct contact between the electrolyte and spinel particles as well as reduce the lithium ion diffusion distance in the inactive layer, leading to greatly improved capacity retention.

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