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To enhance national competitiveness, countries are committed to building a National Human Resource Development (NHRD) system to develop talents. However, studies have rarely investigated the internal development process of the NHRD system and the performance at the system and sub-system levels. Thus, this study constructed the performance evaluation model of the NHRD system from a two-stage process efficiency perspective that first cultivates talents and then uses the talents produced to create value. In addition, considering the problem of international talent flow and the time-lag effect, the bad output and the time-lag between inputs and outputs were incorporated into the model. The subjects included 60 countries, including Argentina, China, and OECD member countries. The results reveal that countries that excel at nurturing talents do not necessarily have the ability to effectively use talents to create value. Only having high-efficiency talent cultivation cannot strengthen competitiveness. Sensitivity analysis was also conducted to identify the input that affects talent cultivation and utilization efficiency, which could be used as a reference for competitiveness and NHRD performance improvement. [ABSTRACT FROM AUTHOR]

In this study, a viscometer, which can measure the viscosity of low-volume liquids (25 μl) within 30 s, was developed on a centrifugal platform. The centrifugal viscometer consists of a disk platform and a motor. Under disk rotation, centrifugal, Coriolis, and viscosity-induced drag forces result in deflection of liquid flow. The viscosity of the liquid sample is determined by the deflection angle of the liquid, which can be examined through image analysis or visual inspection. The viscosities of a series of Newtonian model fluids were tested by the centrifugal viscometer and the results showed good agreement with the ones tested by a conventional rotational viscometer. Since the centrifugal viscometer only requires a motor to function, the microfluidic disk can be produced in large quantities at a low cost through injection molding, and the deflection angle can be detected through visual inspection, it provides an inexpensive, easy to operate, and portable approach to measure low-volume liquid viscosity. [ABSTRACT FROM AUTHOR]

Thermal behavior and solid electrolyte interphase (SEI) are crucial topics for the development and operation of the lithium-ion battery. To investigate the thermal behavior and SEI formation in a lithium-ion battery (C-LiMn 0.5 Ni 0.3 Co 0.2 O 2), a numerical method combining the pseudo-two-dimensional electrochemical model, heat transfer model, and capacity fading model is developed. For the battery operated at a low C-rate, the ohmic heat and the reversible heat dominate the heat generation at a low state of charge (SOC) and high SOC, respectively. Alternatively, the ohmic heat is the dominant factor causing heat generation at a high C-rate. The reversible heat reaches a maximum at the SOC of 65% due to the entropic coefficient of the cathode active materials. The SEI thickness increases around 70 nm with increasing the C rate cycling. The heat generation is the bottleneck for the resistance of Li+ ion conductivity at the SCI. The heat generation of the cathode is larger than that of the anode, which is caused by the low solid phase conductivity of the cathode. This analysis has provided useful insights into the thermal management of lithium-ion battery in the course of charging and discharging which is conducive to the development and safe operation of the battery. • A numerical method model is developed to investigate thermal behavior of a Li-ion battery. • Heat generation at a low C rate is mainly contributed by the reversible heat at high SOC. • Ohmic heat dominates heat generation at a high C rate. • Heat generation of the cathode is larger than that of the anode. • SEI thickness increases around 70 nm with increasing the C rate cycling. [ABSTRACT FROM AUTHOR]

Abstract Lithium diffusion process in an 18650 cell was investigated in-operando using neutron diffraction. The graphite anode delithiation rate and the amount of discharge capacity during the discharging process were correlated with the temperature and current rate. At room temperature, the lithium diffusion rate in LiC 6 phase at the high rate capability (C/5) is same as at low rate capability (C/20), which means that lithium diffusion in LiC 6 crystal phase is independent of the current rate in this range during the discharge process. Lowering temperature to −20 °C decreases both the lithium diffusion and capacity, although the latter can be partially recovered by using lower C-rate. [ABSTRACT FROM AUTHOR]

The rapid rate of technology obsolescence in many high-technology markets makes it imperative for firms to renew their technological bases constantly. Given its critical importance, the technology acquisition from the fast followers’ perspective needs to be the subject of careful analysis. This paper aims to identify the factors influencing fast-follower firms’ choice of technology acquisition model, using a multi-factorial analysis and taking into account their technological capabilities, marketing capabilities, and environmental risk tradeoffs. This study sourced data from the Securities Data Company (SDC) Platinum Database for a total of 205 instances of technological cooperation between technology holders and fast followers in the LED industry. Based on the empirical results, some significant findings were found. First, regarding technological capabilities, when fast-follower firms had greater R&D, complementary manufacturing capabilities, and technological similarities with the partners, they preferred the acquisition model that required higher resource commitments. Secondly, when fast followers had marketing channel advantages, they were more likely to choose a high resource-commitment acquisition model to obtain time-to-market benefits. [ABSTRACT FROM PUBLISHER]

Consumers with different lifestyles often have distinctive needs for the same type of technology products. Previous studies have focused mostly on the characteristics and pricing of these products but there is lack of a comprehensive study on the effect of internal demands from consumers and the sources of external information on intentions to purchase. This study proposes a hybrid decision-making model that integrates product characteristics, consumers’ internal demands and sources of external information for the exploration of behavioural patterns of consumers with different lifestyles when purchasing technology products. The empirical results suggest that lifestyle plays a significant role in moderating consumers’ purchase intentions. Among various consumers, early adopters’ purchase intention is motivated by features that highlight self-personality, while those of the pragmatists and the majority are mainly motivated by ease of contact, work need and sense of group. In addition, both the early adopters and the majority are influenced by the introduction of network and magazines, while the pragmatists are mainly affected by the introduction of retailers. [ABSTRACT FROM PUBLISHER]

Highlights: [•] A Si/graphite composite with sputtered Cu coating served as anode for LIBs. [•] The sputtering Cu coating improved the rate performance of the LIBs. [•] The sputtering Cu coating improved the cycle life of the LIBs. [ABSTRACT FROM AUTHOR]

Abstract: (Sn-Ti)O2 solid solution nanoparticles (denoted (Sn-Ti)O2-500) are prepared by application of one step of chemical treatment followed by calcination in N2 at 500°C for 2h. Transmission electron microscopic (TEM) observations reveal a nanoparticle shape change from needle-like to rod-like after heat treatment. Formation of a (Sn-Ti)O2 solid solution is confirmed by X-ray diffraction (XRD) analysis. The electrochemical properties of the (Sn-Ti)O2 solid solution are studied by cyclic voltammetric and coin cell tests. Electrochemical property results show that (Sn-Ti)O2-500 delivers a specific capacity of about 300mAhg−1, excellent cycle-life performance and high rate-capability during the delithiation process. Inductively coupled plasma results indicate a Sn content in (Sn-Ti)O2-500 of about 10.1% tin to titanium. The promising electrochemical characteristics of (Sn-Ti)O2-500 appear well suited for high-power negative electrodes of lithium ion batteries. [Copyright &y& Elsevier]

In the currently rapidly changing business world, innovation has not only become the key to survival and success, but also the defining challenge of organisations. For latecomer firms, however, because of their inherent resource constraints, innovation has become a far more complex undertaking, similar to a multidimensional puzzle. Although there have been an increasing number of practitioner-based surveys, a discrepancy still remains between academia and industry concerning the role and importance of R&D in innovation. Therefore, this study carried out an industry–university–institution survey of Taiwan, based on a multidimensional framework of the innovation puzzle: human, R&D, flow and connection. The results reveal several interesting clues and provide a better understanding of the innovation puzzle for latecomers, and more importantly, resolves the puzzle that could help latecomers identify where new opportunities lie and what weaknesses they must strengthen. [ABSTRACT FROM AUTHOR]

Abstract: Alkyl- and phenyl-substituted borate anion receptors, triphenyl borate (TPB) and trimethyl borate (TMB), are investigated as electrolyte additives in lithium ion batteries (LiFePO4 cathode, 1 M LiPF6 EC-DMC 1:1 electrolyte) at 25 and 60 °C. TPB shows formation of a thick surface/electrolyte interface (SEI) which hampers ion flow and does not protect the electrode from degradation. Although useful at 25 °C, TPB at 60 °C results in only 7% capacity after 100 cycles, whereas 0.1 M TMB results in 53% capacity. TMB performance improves with increasing concentration. TMB also suppresses thermal decomposition of the electrolyte and formation of the SEI film. [Copyright &y& Elsevier]

Ionic liquids (ILs) have been proposed as electrolytes for long-lived and safe LIBs, since they are nonflammability and have low volatility. The interactions between of cathodes (as olivine LiFePO4 or layered LiNi1/3Mn1/3Co1/3O2 (NMC)) and ionic liquid mixed with organic solvent electrolyte were investigated by cyclic voltammetry, electrochemical impedance spectroscopy (EIS), coin cell test, and scanning electron microscope (SEM). The mixed electrolyte contains ethylene carbonate (EC), dimethyl carbonate (DMC) and ionic liquid such as bis(trifluoromethanesulfonyl)imide (TFSI) and tetraethylammonium (N2222). The results show that the LiFePO4 cathode in this mixed electrolyte had better cycling performance than the NMC cathode. [ABSTRACT FROM AUTHOR]

The dispersion state of conductive carbons in the cathodes of lithium ion batteries fabricated with a dispersant and with/without mechanical milling are considered with regard to the batteries' charge-discharge properties. Suspensions of Ketjen black (KB, EC 300J and EC 600JD) are dispersed in an organic solvent. Ball milling is then performed, modifying the particle sizes and structures. Results show improved dispersion but with collateral reduction of both maximum and average particle sizes. The more fragile EC 600JD, after ballmilling, is broken into more small segments than EC 300J, but with segment density high enough for loose coupling to form networks. Therefore, the electron conduction of EC600JD after ball milling is better than EC 300J. The high-rate discharge capacity of EC600JD after ball milling is also better than that of EC 300J. However, rate capabilities decrease with increasing milling time. [ABSTRACT FROM AUTHOR]

Many firms undertake alliances as a tactic in their competitive strategy to gain technological benefits from their competitors. Little is known, however, about how simultaneous competition and cooperation between rivals (i.e. co-opetition) influence the alliance governance modes. To bridge this deficit, we integrated a variety of different theoretical perspectives into the concept of co-opetition. Based on the dynamic nature of co-opetitive relationships, we also consider the moderating effect of external technological turbulence on the choice of technology alliances. We tested our hypotheses on a sample of 405 international technology alliances in different industries. It was found that the inter-firm co-opetitive relationship results in alliance member preference to choose contractual agreements as the governance mode in new alliances. However, when external technological turbulence increases, firms tend to tighten alliance governance (i.e. through equity joint ventures) in response to the turbulence. [ABSTRACT FROM PUBLISHER]

Abstract: Vinylene carbonate (VC) and vinylene trithiocarbonate (VTC) are studied as electrolyte additives in two kinds of electrolytes: (1) propylene carbonate (PC) and diethyl carbonate (DEC) (1:2 by weight) 1moldm−3 LiPF6; (2) ethylene carbonate (EC) and DEC (1:2 by weight) 1moldm−3 LiPF6. Characterization is performed by cyclic voltammetry, impedance spectroscopy, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and half cell tests. Cyclic life is better in either electrolyte with VC than either electrolyte with/without VTC. SEM shows VC and VTC both form well developed passivation films on the graphite anode, but the films with VTC are thicker than with VC. EIS shows the VTC films have significantly higher charge transfer resistance. The VTC film in PC fails to protect against exfoliation. XPS indicates VTC has different reaction pathways in PC relative to EC. In EC/DEC, VTC forms polymeric C–O–C-like components and sulfide species (C–S–S–C, S and C–S–C). In PC/DEC, VTC does not form polymeric species, instead forming a film mainly containing LiF and Li2S. It appears that a thinner polymeric film is preferential. The specific data herein are of interest, and the general conclusions may help development of improved additives for enhanced Li-ion battery performance. [Copyright &y& Elsevier]

Abstract: The effects of tris(pentafluorophenyl) borane (TPFPB) additive in electrolyte at the LiFePO4 cathode on the high temperature capacity fading were investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), cyclability, SEM and Fourier transform infrared (FTIR). According to the study results, tris(pentafluorophenyl) borane has the ability to improve the cycle performance of LiFePO4 at high temperature. LiFePO4 electrodes cycled in the electrolyte without the TPFPB additive show a significant increase in charge transfer resistance by EIS analysis. SEM and FTIR disclose evidence of surface morphology change and solid electrolyte interface (SEI) formation. FTIR investigation shows various functional groups are found on the cathode material surface after high temperature cycling tests. The results showed an obvious improvement of high temperature cycle performance for LiFePO4 cathode material due to the TPFPB additive. The observed improved cycling performance and improved lithium ion transport are attributed to decreased LiF content in the SEI film. [Copyright &y& Elsevier]

Abstract: IrO2-coated titanium plate electrocatalysts prepared by a dip-coating method (IrO2/Ti) with different calcination temperatures are characterized by scanning electron microscope, X-ray diffraction and X-ray photoelectron spectroscopy. The electrocatalytic behavior of the oxygen reduction reaction (ORR) is evaluated by cyclic voltammetry and galvanostatic electrolysis in 1moldm−3 KOH solution. The effects of calcination temperature on the oxygen reduction pathway are examined. Galvanostatic electrolysis results show that the reaction pathway on the IrO2/Ti electrode prepared at high calcination temperature is mainly a two-electron pathway producing H2O2. It is observed that higher calcination temperatures produce: a more uniform fault-free surface; reduced levels of Cl contamination (residual Cl presumably from incomplete IrCl3 decomposition during the coating process); higher levels of rutile character of the IrO2 layer; lower hydration levels. It is confirmed that ORR electrocatalytic behavior on highly hydrated IrO2 is better than on slightly hydrated IrO2. [Copyright &y& Elsevier]

Abstract: The behavior of methanol adsorption on platinum/poly(2,5-dimethoxyaniline) (Pt/PDMA) composite is investigated using UV–vis spectroscopy (UV–vis) and open circuit potential (OCP). The results of scanning electron microscopy and energy dispersive spectroscopy are used to verify the uniform dispersion of Pt in PDMA. The Fourier transform infrared spectra and OCP results revealed that Pt particles interact with PDMA through the electron-rich nitrogen sites, influencing the oxidation state of PDMA. A model is proposed for the methanol adsorption on Pt particles which changes the interaction between Pt and PDMA. With the proposed model, methanol concentration can be discerned using potentiometric measurements. The results of this study can be applied to methanol sensors for direct methanol fuel cells. [Copyright &y& Elsevier]

Abstract: Electrochemical oxidation of histidine (His) at an anodic oxidized boron-doped diamond electrode (AOBDDE) was performed. A significant peak of His oxidation is observed at about +1.5V vs. Ag/AgCl, however, the response current was inhibited due to strong His-oxidized product adsorption onto the electrode surface. The characteristics of the His-oxidized product adsorbed onto the electrode surface were investigated by studying the electrochemical behavior of the Fe(CN)6 4− redox reaction using cycle voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Both CV and EIS results showed a decrease in the sum of transfer coefficients and an increase in the electron transfer resistance, which indicate that the adsorption film is a non-conductive film. The most possible active site locations for the AOBDDE for His oxidation are within these low-lying polycrystallite AOBDDE surface regions. The results from Raman and X-ray photoelectron spectroscopy offer strong evidence of the imidazole ring reaction from His. Experiments confirmed that the adsorbed film can be removed and the electrode surface reactivated using brief polarization at +2.5V. [Copyright &y& Elsevier]

Abstract: Antimony-coated mesophase graphite powder (MGP) composites are developed as an alternate anode material for Li-ion batteries using an argon atmosphere pyrolysis technique. The specific discharge capacity and cycle life of the Sb-MGP composites are studied. The Sb loading of the Sb-MGP has a significant effect on the composite performance. The Sb-MGP samples demonstrate improved lithium storage capacity. The Sb loading on MGP is optimized experimentally to obtain the maximum reversible capacity for composite electrodes. The reaction processes of lithium intercalation/de-intercalation in MGP and alloying of lithium/Sb are identified by cyclic voltammetry. ICP and EDS measurements confirm the presence of Sb in the MGP matrix. Differential scanning calorimetry (DSC) scans of lithium intercalated anodes show that Sb loading on the MGP material reduces the thermal stability of the anode. [Copyright &y& Elsevier]

Abstract: 2,2-Dimethoxy-propane (DMP) was studied as an additive in 1moldm−3 LiPF6 ethylene carbonate and diethyl carbonate (1:1, w/w) for lithium-ion battery, which was characterized by cyclic voltammetry and half cell tests. Cyclic voltammetry and half cell data show that the use of DMP as an additive to the organic solutions at very low level (ca. 0.005wt%) offers the advantage of forming fully developed passive films on the graphite anode surface. The electrochemical performance of the additive-containing electrolytes in combination with LiCoO2 cathode and graphitic anode was also tested in commercial cells 103448. The results reveal that the cyclic life test and storage performance at high temperature (ca. 60°C) in electrolyte with DMP additive was better than that in an electrolyte without additive. Therefore, DMP can be considered as a desirable additive in electrolyte for lithium-ion batteries operating at high temperature, ca. 60°C. [Copyright &y& Elsevier]

The characteristics of the boron‐doped diamond (BDD) electrode in this work were studied by atomic force microscope (AFM), scanning electron microscopy, and Raman spectroscopy. The electro‐oxidation of formaldehyde at the BDD electrode in 0.5 M K 2 SO 4 with different pH was studied by cyclic voltammetry and amperometry. There is no significant oxidation peak of formaldehyde in acidic solution because the oxidation of formaldehyde is at the potential range of water discharge. However, in neutral solution, there is a well‐defined oxidation peak at about +2.2 V vs. Ag/AgCl. The relation between the response current and formaldehyde concentration is linear behavior at the concentration range from 50 to 600 µM. Besides, in neutral solution, the oxidation of formaldehyde is dominated by indirect oxidation at lower formaldehyde concentration, and it is dominated by direct oxidation at higher concentration. Finally, in alkaline solution, the oxidation of formaldehyde is dominated by indirect oxidation caused by a powerful oxidant and is related to the ratio of the amounts of formaldehyde and OH molecules at the BDD electrode surface. [ABSTRACT FROM AUTHOR]

Abstract: This study uses rotating ring-disk electrode (RRDE) and linear sweep voltammetry (LSV) to characterize oxygen reduction kinetics in alkaline solution on platinum electrodes with various thickness of hydrous oxide (oxyhydroxy) film. Oxyhydroxy films are created on Pt electrodes by pretreatment in 1.0moldm−3 KOH at a constant voltage. The pretreatment voltage ranges from −1.2 to 1.0V and is increased stepwise before each new experimental run to produce seven discreet films. LSV plots show oxyhydroxy film thickness strongly inhibits oxygen reduction and is inversely proportional to RRDE oxygen reduction current I D for LSV voltages E D from −0.1 to −0.46V, but this trend reverses at E D more negative than −0.46V so that the worst-performing electrode becomes the best. However, this improvement disappears at around −0.8V, suggesting this change involves a negatively charged ion, possibly embedded into the metal in the top few atomic layers either interstitially or substitutionally. The 1.0V-pretreated electrode in the E D range from −0.46 to −0.9V of highest oxygen reduction current also exhibits the lowest hydrogen peroxide production, with zero H2O2 produced at −0.6V, indicating the brief presence of the oxyhydroxy film on the Pt surface has strong lingering effects. The post-oxyhydroxy Pt surface is very different than the native Pt for oxygen reduction pathway and efficiency. Reaction order with respect to oxygen is close to 1. The rate constants of the direct O2 to H2O electroreduction reaction are increased with decreasing the potential from −0.2 to −0.6V, but the O2 to H2O2 electroreduction is contrary to this expectation. The rate constants of H2O2 decomposition on the oxyhydroxy film-covered Pt electrode are near constant around 1×10−4 cms−1 at E D >−0.5V. [Copyright &y& Elsevier]

Abstract: Electropolymerizations (EPs) of thiophene (Th), 3,4-ethylenedioxythiophene (EDOT) and the mixed monomers of Th and EDOT in 0.05M Et4NClO4/propylene carbonate (PC) solution were performed to prepare polymer films as potential cathode materials in lithium ion battery. The incorporation of EDOT units into pure polythiophene (PTh) chain leads to large alternations on the experimental conditions of EPs and the properties of the resulting polymer films. Onset potential of the EPs was reduced with the participation of EDOT component. The resulting polymers, PTh, poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(thiophene-co-3,4-ethylenedioxythiophene) (PTh–EDOT) were then served as cathode materials to test their capabilities to transport lithium ion in 1.0M LiPF6/ethylene carbonate/dimethyl carbonate solution. With the inherent EDOT unit, PEDOT and PTh–EDOT have better charge capacity, stability and response rate than pure PTh. Among the copolymers, PTh–EDOT (1/1) even shows better stability than pure PEDOT homopolymer, advantage of using EDOT as copolymer component is thus evaluated. [Copyright &y& Elsevier]

In this study, an electrode slurry composed of molybdenum disulfide (MoS2) and vapor-grown carbon fiber (VGCF) prepared through a solid-phase synthesis method was blade-coated onto copper foil to form a thick film as the anode for lithium-ion batteries. In previously reported work, MoS2-based lithium-ion batteries have experienced gradual deformation, fracture, and pulverization of electrode materials during the charge and discharge cycling process. This leads to an unstable electrode structure and rapid decline in battery capacity. Furthermore, MoS2 nanosheets tend to aggregate over charge and discharge cycles, which diminishes the surface activity of the material and results in poor electrochemical performance. In this study, we altered the density of the MoS2–carbon fiber/Cu foil anode electrode by rolling. Three different densities of electrode sheets were obtained through varying rolling repetitions. Our study shows the best electrochemical performance was achieved at a material density of 2.2 g/cm3, maintaining a capacity of 427 mAh/g even after 80 cycles. [ABSTRACT FROM AUTHOR]

Two camptothecin derivatives, 10-cyclohexyl-7-methyl-20(S)-camptothecin and 7-methyl-10-morpholino-20(S)-camptothecin, were synthesized and their differences in solubility were investigated using four chosen solvent systems. Based on our results, 10-cyclohexyl-7-methyl-20(S)-camptothecin exhibited higher solubilities than 7-methyl-10-morpholino-20(S)-camptothecin in polar aprotic solvents. However, these two camptothecin derivatives did not exhibit apparent differences in solubility between 5% dimethyl sulfoxide (DMSO)/95% normal saline co-solvent system and 5% dimethylacetamide (DMAC)/95% normal saline co-solvent system. To rationalize their differences in solubility, we also tried to perform a DFT-B3LYP study to investigate their interaction with one water molecule. [ABSTRACT FROM AUTHOR]

The core-food (CF) approach, first adopted in the United States in the 1980s, has been widely used by many countries to assess the exposure to dietary hazards at a population level. However, the reliability of exposure estimates (C × CR) depends critically on sampling methods designed for the detected chemical concentrations (C) of each CF to match with the corresponding consumption rate (CR) estimated from the surveyed intake data. In order to reduce the uncertainty of food matching, this study presents a sampling design scheme, namely the subsample method, for the 2016 Taiwan total diet study (TDS) on veterinary drugs. We first combined the four sets of national dietary recall data that covered the entire age strata (1–65+ years), and aggregated them into 307 CFs by their similarity in nutritional values, manufacturing and cooking methods. The 40 CFs pertinent to veterinary drug residues were selected for this study, and 16 subsamples for each CF were designed by weighing their quantities in CR, product brands, manufacturing, processing and cooking methods. The calculated food matching rates of each CF from this study were 84.3–97.3%, which were higher than those obtained from many previous studies using the representative food (RF) method (53.1–57.8%). The subsample method not only considers the variety of food processing and cooking methods, but also it provides better food matching and reduces the uncertainty of exposure assessment. [ABSTRACT FROM PUBLISHER]

The submicro-sized and nanostructured Si aggregated powder is prepared by combinational routes of high energy mechanical milling (HEMM) and wet milling. Milled Si powder is investigated by particle size analyzer, SEM, TEM, XPS and XRD as well as the control ones. Its electrode is also investigated by in situ XRD and electrochemical performance. Morphology reveals that combining the high energy mechanical milling and wet milling not only fracture primary Si particles but also form submicro-sized Si aggregates constructed by amorphous and nanocrystalline phases. Moreover, XPS shows that wet milling in ethanol trigger Si O CH 2 CH 3 bonding on Si surface might enhance the SEI formation. In situ XRD analysis shows negative electrode made of submicro-sized Si aggregated powder can effectively suppress formation of crystalline Li 15 Si 4 during lithiation and delithiation due to amorphous and nanocrystalline construction. Thus, the submicro-sized Si powder with synergistic effects combining the high energy mechanical milling and wet milling in ethanol as negative electrode performs better capacity retention. [ABSTRACT FROM AUTHOR]

We report the high performance of the manganese oxide/reduced graphene oxide (MnOx/rGO) nanocomposite as an anode electrode of a lithium-ion battery. The composite is synthesized by a low temperature (83 °C) chemical solution reaction, and shows relatively high specific capacities (660 mAh g −1 ) after 50 cycles. For MnOx/rGO composites, the cycling stability is increased remarkably as compared to that seen with individual MnOx, and this is due to the synergistic effects of both the components in the composite. The rGO acts as a conductive buffer layer that suppresses the volume change of MnOx, and simultaneously promotes the conductivity of MnOx. The functional groups of graphene oxide facilitate MnOx formation at low temperature, and this retains the MnOx-graphene oxide connection, thus improving the capacity and cycling stability. [ABSTRACT FROM AUTHOR]

We investigated the effectiveness of using methylboronic acid MIDA ester (ADM) as an additive in an electrolyte to enhance the overall electrochemical and material properties of an LNCAO (LiNi0.8Co0.15Al0.05O2) cathode. The cyclic stability of the cathode material measured at 40 °C (@ 0.2 C) showed an enhanced capacity of 144.28 mAh g−1 (@ 100 cycles), a capacity retention of 80%, and a high coulombic efficiency (99.5%), in contrast to these same properties without the electrolyte additive (37.5 mAh g−1, ~ 20%, and 90.4%), thus confirming the effectiveness of the additive. A Fourier transform infrared spectroscopy (FTIR) analysis distinctly showed that the ADM additive suppressed the EC-Li+ ion coordination (1197 cm−1 and 728 cm−1) in the electrolyte, thereby improving the cyclic performance of the LNCAO cathode. The cathode after 100 charge/discharge cycles revealed that the ADM-containing system exhibited better surface stability of the grains in the LNCAO cathode, whereas distinct cracks were observed in the system without the ADM in the electrolyte. A transmission electron microscopy (TEM) analysis revealed the presence of a thin, uniform and dense cathode electrolyte interface (CEI) film on the surface of LNCAO cathode. An operando synchrotron X-ray diffraction (XRD) test identified the high structural reversibility of the LNCAO cathode with a CEI layer formed by the ADM, which effectively maintained the structural stability of the layered material. The additive effectively inhibited the decomposition of electrolyte compositions, as confirmed by X-ray photoelectron spectroscopy (XPS). [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIB) with titanium dioxide as anode material emerged as one of the most energy-storage systems. In this study, we investigate aluminum-doped non-stoichiometric titanium dioxide synthesized using sol-gel method and subsequent reduction treatment. Different analysis techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) tests are conducted for the analysis of material and performance of the battery. The XRD results affirmed that the sample consisted of pure titanium-dioxide phases with no other precipitated phases, such as aluminum oxide (α-Al 2 O 3 or γ-Al 2 O 3). XPS analysis evident that aluminum was successfully incorporated into the titanium-dioxide lattice and the presence of Ti3+ and oxygen vacancy signals confirmed its non-stoichiometric nature. TEM images implies that doping and its extent did not significantly affect the size and morphology of the nanoscale particles. The selected area electron diffraction shows that the sample consisted of a mixture of the anatase and rutile phases. The best-performing electrode was found to be the one composed of 1 % aluminum-doped non-stoichiometric titanium dioxide. After 200 charge-discharge cycles, the battery maintained a capacity of 195 mAh/g, retaining 97.5 % of its reversible capacity. Cyclic stability test under high current condition shows that the capacity remained at 157 mAh/g without any noticeable decay after 750 charge-discharge cycles at a 1 C rate. This material exhibited the lowest impedance and the highest lithium-ion diffusion rate. Additionally, in situ synchrotron-based XRD indicates coexistence of three phases such as a new reversible intermediate phase LiTiO 2 , a partially irreversible intermediate phase Li 0.55 TiO 2 , and the anatase phase. The analysis results indicated that the peak intensities and angular shifts were associated with the phase changes that occurred during charge and discharge of the electrochemical processes. The interaction mechanism study between lithium ions and the lattice of mixed phase (anatase, rutile) identified the occurrence of non-uniform stress resulting from lithium-ion insertion in the rutile phase, in addition to the irreversible reactions in both the rutile and anatase phases. Through the synergistic effect of heteroatom doping and oxygen vacancy treatment, the conductivity of titanium dioxide is enhanced, leading to improved performance in capacity, impedance, cycle life, and rate as an anode material in LIBs. • Synthesis of Al-doped TiO 2 for anode application. • Long-term stable cycling of Al-doped TiOx anode materials. • Characterization of Li intercalation and deintercalation by in-operando XRD. [ABSTRACT FROM AUTHOR]

Highlights: [•] Preparation of 26S proteasome modified electrode. [•] Effect of ATP on 26S proteasome. [•] 26S proteasome modified gold electrode in an electrolytic solution without lithium perchlorate. [•] 26S proteasome modified gold electrode for ATP detection did not interfere with albumin and 26S proteasome. [•] The recognition and quantification of ATP in pig plasma. [ABSTRACT FROM AUTHOR]

Cutting is an essential process in touch panel manufacturing, which concerns the effectiveness of whole touch panel manufacturing process and reliability of final application products. An alternative is laser cutting technology, which is expected to eclipse conventional cutting method in terms of cost and quality. The laser cutting quality of touch panel is determined by the appropriation of value settings of several parameters/factors involved in the complex laser cutting process. However, the parameter/factor adjusting method applied in practice mainly relies on the engineer's experience and trial-and-error experiment, which are unsystematic and susceptible to inefficiency and ineffectiveness. This study proposes a procedure for parameter/factor optimization of the touch panel laser cutting process to obtain maximum cutting quality. The proposed optimization procedure is successfully applied in a real case of laser cutting for projected capacitive touch panel, a type of touch panels using capacitive technology; it gradually becomes mainstream in the newly emerged information appliance marketplace. Results reveal that defect rate of the laser cutting process decreases from 32.6% to 0.3% once the proposed procedure on this paper is implemented, and this achievement outperforms other optimization strategies. [ABSTRACT FROM PUBLISHER]

Abstract: Nano-scale carbon materials such as Ketjenblack (KB) was used to combine with traditional conductive polymer such as poly(3,4-ethylenedioxythiophene) (PEDOT) and LiCoO2 to prepare composite cathode for lithium-ion (Li-ion) battery. The PEDOT/LiCoO2–KB cathodes were made by electrochemical deposition of 3,4-ethylenedioxythiophene (EDOT) monomer on the pre-formed LiCoO2–KB electrodes with 1 and 5wt% of KB content. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to confirm the successful coating of PEDOT layer on the LiCoO2 and KB components. To evaluate the effect of PEDOT coating, LiCoO2–KB electrodes with and without PEDOT component were then tested and compared their results from different electrochemical characterizations. Homogeneity of the KB component and the presence of conductive PEDOT layer are found to be important factors in controlling the cathode properties such as the involved capacity, cycle ability, intercalation/de-intercalation rate and rate capability. [Copyright &y& Elsevier]

Abstract: A composite electrode material, poly(3,4-ethylenedioxythiophene) (PEDOT)/LiCoO2-carbon fibers (VGCF) from a continuous process of electrochemical deposition of 3,4-ethylenedioxythiophene (EDOT) monomer on the pre-formed LiCoO2-VGCF electrode, was prepared and characterized to test its applicability in lithium-ion battery. Compared to the bare LiCoO2-VGCF electrode, use of PEDOT/LiCoO2-VGCF composite as cathode in lithium-ion battery has enhanced properties such as the cyclability, electrochemical stability, intercalation/deintercalation rate of lithium ion and rate capability. Scanning electron microscope shows the successful coating of PEDOT on the LiCoO2 particles and the VGCF fibers. The differential scanning calorimetry (DSC) scans of the charged cathodes show that incorporation of PEDOT reduces the thermal stability of the cathode. [Copyright &y& Elsevier]

Abstract: Electrochemical copolymerization of 3-trimethoxysilanyl-propyl-N-aniline (TMSPA) with 2,5-dimethoxyaniline (DMA) was performed in 1M HCl aqueous solution for different feed ratios of TMSPA using cyclic voltammetry. The deposition rate of TMSPA–DMA copolymer is higher than that of PTMSPA but lower than that of PDMA. (TMSPA-co-DMA) film was deposited using electrochemical polymerization as conducting film on indium tin oxide (ITO) electrode and used as an electrode in an electrochromic device. Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) was spin-coated on ITO as the other electrode. Carboxyl-terminated- butadiene-acrylonitrile (CTBN) blended with LiClO4 was used as solid polymer electrolyte. A total solid electrochromic device was assembled as follows: ITO|P(TMSPA-co-DMA)∥LiClO4-CTBN∥PEDOT:PSS|ITO. The columbic efficiency of the devices reached to 104% for P(TMSPA-co-DMA) film with TMSPA feed ratio of 0.25. The optical contrast (ΔT, %) of the single electrode and the device were determined by UV–vis spectroelectrochemical studies. The stability of ΔT was improved during color switching from +1.5 to −1.5V (vs. PEDOT) for this device. The device was pale yellow at −1.5V and blue at +1.5V. [Copyright &y& Elsevier]

Oxygen reduction in phosphate solution with the Cu(II) complex of 1,10-phenanthroline (phen) at a glassy carbon electrode was investigated by employing cyclic voltammetry, chronocoulometry and rotating disc electrode techniques. Cyclic voltammetric results indicated that the oxygen reduction was catalyzed by Cu(II)/Cu(I) complex of 1,10-phenanthroline in phosphate solution at a glassy carbon electrode. Choronocoulometric results showed the amount of the adsorption of [Cu(phen)2]2+ was increased with [Cu(phen)2]2+ concentration and was slightly increased with electrode potential from −0.20 to −0.90 V. On the basis of measurements using rotating disc electrode together with polarization curves, Tafel slopes, and electron transfer numbers determination, the oxygen reduction with the Cu(II) complex at a glassy carbon electrode was proposed. The addition of a small quantity (10 μM) of the Cu(II) complex of 1,10-phenanthroline in the phosphate solution enhanced the electrocatalytic activity to four-electron transfer for O2 reduction and inhibited the hydrogen evolution during oxygen reduction at a glassy carbon electrode. [Copyright &y& Elsevier]

Relative solid electrolyte interphase (SEI) film thickness investigation on graphite electrodes after the first charge state in the lithium‐ion battery was successfully demonstrated by the ex‐situ small‐angle neutron scattering technique. Here, for both the mesophase graphite powder (MGP) and the fine‐mesophase graphite powder (FMGP) anodes, with two different particle sizes was analyzed precisely by the Guinier–Porod model. The data revealed a stable, maximum (~tens of nm) bi‐layer SEI film formed on MGP anode in ethylene‐carbonate/dimethyl‐carbonate (EC/DMC) at a capacity of 50 mAh/g and sluggish above 100 mAhg‐1. The SEI formed on FMGP with and without 3 wt% fluoroethylene‐carbonate additive in EC/DMC showed the relative thickness greater than that only in ethylene‐carbonate/diethyl‐carbonate. Lithiation initiated the rapid SEI formation on the graphite surface and achieved a maximum thickness in the cell potential ≤0.2 V, and became thinner when the graphite particle expanded after Li+ intercalation. It was observed that the SEI thickness influenced the electrolytes and additives, which might ultimately impact battery performance. Our preliminary results make evident that small‐angle neutron scattering could be employed to better understand the complex microstructure solid electrolyte interphase formation and its accurate thickness, on a mesophase graphite anode. [ABSTRACT FROM AUTHOR]

In this study, a new monitoring method was developed, titled infrared thermal imaging technology, which can effectively evaluate the thermal effect of the charge-discharge test in the vanadium/iodine redox flow battery (V/I RFB). The results show that the all-vanadium redox flow battery (all-V RFB) has a greater molar reaction Gibbs free energy change than that of the V/I RFB, representing a large thermal effect of the all-V RFB than the V/I RFB. The charge-discharge parameters, flow rate and current density, are important factors for inducing the thermal effect, because of the concentration polarization and the ohmic resistor. The new membrane (HS-SO3H) shows a high ion exchange capacity and a good ions crossover inhibitory for the V/I RFB system, and has a high coulomb efficiency that reaches 96%. The voltage efficiency was enhanced from 61% to 86% using the C-TiO2-Pd composite electrode as a cathode with the serpentine-type flow field for the V/I RFB. By adopting the high-resolution images of an infrared thermal imaging technology with the function of the temperature profile data, it is useful to evaluate the key components' performance of the V/I RFB, and is a favorable candidate in the developing of the redox flow battery system. [ABSTRACT FROM AUTHOR]

The abnormal lattice expansion of commercial polypropylene (PP)/polyethylene (PE)/polypropylene (PP) separator in lithium-ion battery under different charging current densities was observed by in-situ X-ray diffraction. Significant lattice changes of both PP and PE were found during the low current density charging. The capacity fading and the resistance value of the cell measured at 0.025 C (5th retention, 92%) is unexpectedly larger than that at 1.0 C (5th retention, 97.3%) from the electrochemical impedance spectroscopic data. High-resolution scanning electron microscopy is employed to witness the pore changes of the trilayered membrane. Density functional theory calculations were used to investigate the mechanism responsible for the irregular results. The calculations revealed that the insertion of Li-ion and EC molecule into PP or PE are thermodynamically favourable process which might explain the anomalous significant lattice expansion during the low current density charging. Therefore, designing a new separator material with a more compact crystalline structure or surface modification to reduce the Li insertion during the battery operation is desirable. [ABSTRACT FROM AUTHOR]

We demonstrate a facile, single step, low temperature and energy efficient strategy for the synthesis of SnO 2 -reduced graphene oxide (RGO) nanocomposite where the crystallization of SnO 2 nanoparticles and the reduction of graphene oxide takes place simultaneously by an in situ chemical reduction process. The electrochemical property of the SnO 2 -RGO composite prepared by using low concentrations of reducing agent shows better Li storage performance, good rate capability (378 mAh g −1 at 3200 mA g −1 ) and stable capacitance (522 mAh g −1 after 50 cycles). Increasing the reductant concentration lead to crystallization of high concentration of SnO 2 nanoparticle aggregation and degrade the Li ion storage property. [ABSTRACT FROM AUTHOR]

The sodiation and desodiation of sodium (Na) into the Super-P carbon anode material were investigated using electrochemical analyses, high-resolution transmission electron microscopy (HRTEM), and neutron powder diffraction (NPD). In the sodiated Super-P carbon, sodium is stored both in the graphite interlayer space of carbon nano-particles and pores between the particles. Sodium metal clusters found in micro-pores between the carbon particles are responsible for the large irreversible capacity of the Super-P electrode. The graphite interlayer distance increases on sodiation from 3.57 Å to two distinct values of ∼3.84 and 4.41 Å. The mechanism of the process is discussed. [ABSTRACT FROM AUTHOR]

The influences of adding vanadium to the structure evolution and electrochemical performance of LiFePO 4 are systematically investigated by in-situ X-ray powder diffraction and X-ray absorption near edge structure spectroscopy. The results indicate that the addition of a small amount of vanadium (less than at 1%) significantly reduces the formation of non-crystalline (highly disordered) triphylite and remnant heterosite phases in the cathode of battery especially at the rate capability higher than 0.5C. The cycle stability of LiFePO 4 cathode with vanadium additive after 80 cycles is improved by 14.9% compared to that without vanadium additive. Such an enhancement could be attributed to the ion diffusion kinetics being improved and inactive triphylite being reduced by the supervalent-vanadium additive in cathode during electrochemical redox cycles. [ABSTRACT FROM AUTHOR]

Abstract: Ketjen black (KB) has a large specific surface area and is potentially more effective as the cathode conductive additive. However, large KB flakes often overlay together to form thick stacks. In order to overcome this problem, maleic anhydride (MA) was grafted onto the KB surface by a plasma-induced method. Such a MA-KB additive was found to have a more homogeneous distribution in the LiFePO4 cathode, which resulted in a reduction in the electrical resistivity and electrode polarization. As the consequence, greatly improved cell performance was achieved, including higher capacity, higher discharge voltage, higher rate capability, longer cycle lifetime, and a much flatter discharge curve. Detailed analysis on the discharge curves and the electrochemical impedance spectroscopy showed that although both the electrical resistivity and electrode polarization were reduced by the better distribution of the MA-KB additive, the reduction in electrode polarization was more important in cutting the capacity loss. [Copyright &y& Elsevier]

Abstract: Detection of 26S proteasome, a multiproteolytic complex that degrades intracellular proteins in eukaryotic cells, by electrochemical methods is of interest for improved understanding of living cells and detection of cancer. This study develops an electrochemical system to detect 26S using a gold electrode modified by a self-assembled monolayer of 1,6-hexanedithiol (HDT) for capture of 26S proteasomes. When 26S is fixed on a HDT-gold electrode, it is found that electrolyte anions can enhance detection but also cause damage to the HDT layer. Cyclic voltammetry and electrochemical impedance spectroscopy demonstrate that HDT stability is better in LiClO4 solution than in sodium sulfate (Na2SO4) solution. Chymotrypsin-like activity of 26S as measured by fluorescence with Suc-LLVY-AMC substrate declines 10% with LiClO4 and 25% with Na2SO4. LiClO4 is a better electrolyte salt in a 26S-HDT-gold electrode application in Tris buffer. Increased electron transfer resistance is observed after binding 26S on the HDT-gold electrode. Stable 26S concentration is from 2 to 100nM. As 26S concentration increases from 2 to 100nM, the electron-transfer impedance of Fe(CN)6 4−/3− redox rises logarithmically. The range of electrochemical detection of 26S proteasome is nanomolar. [Copyright &y& Elsevier]

Abstract: This paper reports an amplification procedure application of multi-functionalized gold nanoparticles (MFAuNPs) which was used for electrochemical impedance immunosensor. The modified electrode which was utilized for the affinity adsorption of protein A, was fabricated by stepwise immobilization of 1, 6-hexanedithiol, AuNPs, and IgG on the gold electrode via self-assembling technique. The interfacial properties of the modified electrodes were evaluated in the presence of couple redox as a probe by cyclic voltammetry and electrochemical impedance spectroscopy. An equivalent circuit model with a constant phase element was used to interpret the obtained impedance spectra. The electrochemical behavior of the redox probe was affected by the accumulation of treated substances on the electrode surface. There is no significant increase in the electron transfer resistance after the binding of protein A to IgG on the electrode surface without amplification. The changes in the electron transfer resistance on the IgG-modified electrodes became more sensitive after the MFAuNPs were introduced for signal amplification. The increments of amplified impedance showed good correlation of the detection of protein A in the range of 5–1000pg/mL with a detection limit of 1pg/mL. The development of a rapid, facile, and sensitive amplification method capable to detect biomolecules in the picogram range, utilizing EIS measurement, may be achieved in this study. [Copyright &y& Elsevier]

Abstract: We report the characterization of triphenylamine-based hole-transporting material, N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1, 1′-biphenyl-4,4′-diamine (TPD), used in the electrochromic devices. The electrochromic properties of different TPD thickness were studied by employing the electrochemical and spectroelectrochemical methods. Cyclic voltammograms of TPD films on an indium tin oxide (ITO)-coated glass exhibited one reversible redox couple in the range of 0–1.4V versus Ag/AgCl in 0.1N HClO4. To assemble the dual-type electrochromic devices using different thickness (250, 400, and 1000nm) of TPD films: ITO/TPD//PU-LiClO4//PEDOT/ITO, the optical contrast of the devices increases with increasing the TPD film thickness, whereas the 1000nm TPD film showed relatively excellent stability with respect to the electrochromic characteristics as compared to 250 and 400nm films; the color of the film changed from orange-brown, transparent, and dark blue at −2.0, 0.0, and +2.0V (vs. PEDOT), respectively, where PEDOT is poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulfonate). [Copyright &y& Elsevier]

• First report on room temperature, bottom up approach for the synthesis SiOx/rGO composite. • Formation of SiOx is confirmed by XRD and XPS. • Uniform distribution of SiOx over rGO sheets. • Enhanced capacity of 749 mAh g−1 in the first cycle. • Possibility of enhancement of the device functionality by altering the synthesis procedure. We explore a simple, room temperature, bottom up approach for the synthesis of SiOx dispersed over rGO (reduced graphene oxide) sheets forming SiOx/rGO composite. X-ray diffraction analysis confirmed the formation of SiOx with the major peak position at 21.9° Bragg angle. The microstructure of the composite revealed a layer like morphology and the uniform distribution of SiOx as observed by the element mapping in the transmission electron microscopy. The SiOx/rGO composite was used as anode in lithium ion battery and the composite achieved appreciable capacity (749 mAh g−1 @100 mA g−1) in the first cycle and 61 mAh g−1 at 100 charge/discharge cycles with 99% coulombic efficiency. [ABSTRACT FROM AUTHOR]

The tumor suppressor gene p53 plays an important role in guarding genomic integrity. When induced in response to environmental results, the gene product of p53 functions as a transcription factor to transactivate genes involved in arresting the cell cycle and as a facilitator of DNA repair. In contrast, the status of p53 in Chinese hamster ovary (CHO) cells, commonly used as a model system for various studies including those involving the cell cycle and transformation, remains an enigma. In this study, the function and sequence of p53 in CHO.K1 cells were investigated. The level of p53 proteins was elevated on ultraviolet (UV) irradiation of the cells, and the proteins formed specific complexes as probed with DNA containing p53-binding sequences. Its activities toward responsive promoters were inducible by UV in a dose-dependent manner. Although p53 in CHO.K1 contained a single missense mutation at codon 211, the mutation apparently had no effect on the functional properties of the protein. The CHO.K1 cells on X-ray irradiation failed to arrest at G1 phase even when the cells were transfected with a wildtype human p53 gene, indicating that the failure probably was not caused by dysfunction of its p53, but by some other mechanism. This result is consistent with the finding that p21(Waf1/Cip1) is undetectable in UV-treated CHO.K1 cells, whereas Gadd45 is induced by UV light in the cells. [ABSTRACT FROM AUTHOR]

• Dopamine self-assemble on irregularly sub-micron sized Si/Cu 3 Si aggregates. • Self-assembled dopamine further to form sheet-like carbon framework after pyrolysis. • Dispersed Cu 3 Si as catalyst induced CCVD, enhances carbon shell crystallinity. • Cu 3 Si reinforced nitrogen doping into carbon shell. A chemical vapor decomposition (CVD) enhanced carbon coated Si/Cu 3 Si composite aggregate (C-Si/Cu 3 Si@C) is prepared as anode material to alleviate volume expansion and improve the electrochemical performance for lithium-ion batteries (LIBs). In this work, micron-sized C-Si/Cu 3 Si@C is fabricated through self-assembling of dopamine as first carbon precursor on irregularly shaped and sub-micron-sized Si/Cu 3 Si composite, followed by CVD with ethylene (C 2 H 4) as second carbon precursor. Besides, dopamine not only self-assembles on the surface of Si/Cu 3 Si composite but also grows into sheet-like film that supports and connects Si/Cu 3 Si composite into micron-sized aggregate. In addition to CVD, Cu 3 Si induces catalytic chemical vapor deposition (CCVD), which enhances integrality of the carbon shell as well as reinforce nitrogen doping into carbon shell to enhance conductivity. Therefore, the C-Si/Cu 3 Si@C composite performs in optimum condition when the cycle is stable, attaining delithiation capacity of 2101 mAh g−1, coulombic efficiency of 84.7% for the 1st cycle and achieves capacity retention of 82.9% after 100 cycles. [Display omitted] [ABSTRACT FROM AUTHOR]