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• The problem of overdetermined system of time-varying linear equations is firstly solved with the sixth-order approximation. • Theoretical analysis and experiments are provided to validate the availability and superiority of the proposed algorithm. • Applications of mobile localization are provided to show the applicability and effectiveness of the proposed algorithm. • The proposed algorithm is indicated to be useful for mobile localization of high precision. The challenges of the inefficiency of the existing static least-squares method and the insufficient precision of the existing neural algorithms need to be overcome. With the aid of the ten-instant Zhang time discretization formula, a novel ten-instant discrete-time neural network algorithm is proposed and generalized to the problem-solving of overdetermined system of time-varying linear equations. Theoretical analyses illustrate that the maximal steady-state residual error of the proposed algorithm has an order-6 pattern. Comparative experiment results further substantiate the superiority of the proposed algorithm. Moreover, applications of mobile localization based on the angle of arrival technique and the time difference of arrival technique are provided to display the applicability of the proposed algorithm. [ABSTRACT FROM AUTHOR]

AlCrN coatings were deposited on 316L stainless steel by multi-arc ion plating. The phase structures were controlled and optimised by vacuum annealing at 700 °C, 800 °C, and 900 °C, each for 2 h. The microstructures and morphologies of these coatings were examined by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscope, in association with adhesion strength measurement, residual stress measurement and potentiodynamic polarisation with 3.5% NaCl and 10% H 2 SO 4 solutions. Results show that the solid solution hcp-(Cr, Al)N phase of as-deposited AlCrN coatings decomposes into hcp-AlN and CrN phases, then further decompose into N and Cr with increasing annealing temperature. Metal particles and droplets on the coating surface were gradually removed simultaneously when compared with as-deposited coatings. The highest adhesion strength was obtained after annealing at 700 °C. It decreased with increasing annealing temperature due to the σ-FeCr phase and Cr 2 N phases, and the residual stress decreasing. The potentiodynamic polarisation measurements showed that the corrosion resistance of such coatings was significantly improved after annealing: the coatings annealed at 800 °C showed the best protective efficiency because some corrosion resistance phases (h-AlN, Al 2 O 3 , CrN, and Cr 2 N) were generated. [ABSTRACT FROM AUTHOR]

The highly oriented macroporous graphene monoliths hybridized with carbon-coated metal oxide or phosphate (C/M/GM) with core/shell structure were fabricated by an ice-templating co-assembly of M/GO nanosheets (metal oxide/phosphates decorated graphene oxide) and polyvinyl alcohol (PVA), and following thermal treatment. With either tin oxide (SnO 2 ) or iron phosphate (FePO 4 ), the resulting C/M/GMs possess periodic macropores with diameters ranging from 5 to 20 μm and high loading contents of active components (~70 wt%). Served as the anode in LIBs, C/SnO 2 /GM maintains an ultrahigh capacity of 1665 mA h g −1 at a current density of 0.2 A g −1 for 200 cycles. Even at an ultrafast charge rate of 10 A g −1 , a decent capacity of 300 mA h g −1 can still be achieved, with excellent cycling stability. And C/FePO 4 /GM also delivers a highly reversible capacity of 175 mA h g −1 at a current density of 0.05 A g −1 for 150 cycles and a good capacity of 57 mA h g −1 at 2 A g −1 when as the LIB cathode electrode. [ABSTRACT FROM AUTHOR]

Abstract: A novel synthetic method toward nitrogen containing positively charged dibenzo[jk,mn]naphtho[2,1,8-fgh]thebenidinium (DBNT, 1) salts was developed. In this method, the undehydrogenated precursor of DBNT, 14-phenyl-14-dibenzo[a,j]acridinium salt (6), was produced directly from the reaction between 14-phenyl-14-dibenzo[a,j]xanthenylium (2) and amine/aniline in reasonable yield. Various DBNT salts with different alkyl and alkylphenyl chains were synthesized in this two-step method. The self-assembly behavior of two alkylated DBNT salts, 1c and 1f, was studied in this work. Due to the different substituents and counterions, compound 1c formed nanoscale wirelike fibers, and helical aggregates were obtained from 1f, in their methanolic solutions. [Copyright &y& Elsevier]

Abstract We consider the Brézis–Nirenbergproblem: { − Δ u = | u | 2 ⋆ − 2 u + λ u in Ω , u = 0 on ∂ Ω , where Ω is a smooth bounded domain in R N , N ≥ 3 , 2 ⋆ = 2 N N − 2 is the critical Sobolev exponent and λ > 0. Our main result asserts that if N ≥ 4 then there exists a pair of sign-changing solutions of the problem for every λ ∈ (0 , λ 1 (Ω)) , λ 1 (Ω) being the first eigenvalue of − Δ in Ω with Dirichlet boundary conditions, while if N = 3 then a pair of sign-changing solutions exists for λ slightly smaller than λ 1 (Ω). Our approach uses variational methods together with flow invariance arguments. [ABSTRACT FROM AUTHOR]

Two‒dimensional polymeric carbon nitride (2DPCN) is a versatile support for constructing single atom catalysts (SACs). Herein, we demonstrated a facile strategy for constructing atomic Co sites on 2DPCN. Atomic dispersion of Co was confirmed by the aberration‒corrected high angle annular dark field scanning transmission electron microscopy, while the extended X‒ray absorption fine structure spectroscopy analysis precisely corroborated the existence of atomic Co1–N 4 non square planar sites on 2DPCN support. Remarkably, Co1/2DPCN catalyst yielded H 2 at a rate of 28.3mmol H2 h−1 g Co −1, which is approximately 4.2 times higher than that of CoNPs/2DPCN (6.8mmol H2 h−1g Co −1) counterpart. Notably, with 0.75 wt % Pt as a co‒catalyst, H 2 evolution activity for Co1/2DPCN and CoNPs/2DPCN reached as high as 138.6 mmol H2 h−1 g metal −1 and 22.4mmol H2 h−1 g metal −1, respectively, which could be attributed to the synergistic effect of atomic Co1–N 4 sites and Pt. Both DFT calculations and spectroscopic results revealed that as constructed atomic Co1–N 4 sites, reduced band gap energy, improved light harvesting ability and decreased energy barrier for H 2 evolution. [Display omitted] • Demonstrated facile synthesis of Co single atoms on 2D polymeric carbon nitride support (Co1/2DPCN). • XAS analysis revealed the presence of distinct non square planar Co–N 4 atomic sites. • Atomic Co–N 4 sites promoted light absorption and directional charge transfer. • The atomic Co1/2DPCN catalyst achieved 28.3mmol H2 h−1 g Co −1 activity without the assistant of noble metal co‒catalyst. • Proposed H 2 evolution mechanism on the basis of experimental results and DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with the stability and periodicity for a class of impulsive neural networks with delays. By means of the Fixed point theory, Lyapunov functional and analysis technique, some sufficient conditions of exponential stability and periodicity are obtained. We can see that impulses do contribution to the stability and periodicity. An example is given to demonstrate the effectiveness of the obtained results. [Copyright &y& Elsevier]

Abstract: This paper is concerned with a class of the impulsive bidirectional associative memories neural networks that possesses a Cohen–Grossberg dynamics incorporates time delays and variable coefficients. The existence of equilibrium point, globally exponential stability and globally exponentially robust stability are investigated by Lyapunov function and Halanay inequality. We can see that impulses do contribution to the exponential stability and robust stability. An illustrative example is given to demonstrate the effectiveness of the obtained results. [Copyright &y& Elsevier]

Some new azo-metal chelates were synthesized using different diazo components, coupling components and metal ions. Their structures were confirmed by IR spectra, MS spectra and UV–Vis spectra. Their solubility in 4-hydroxy-4-methyl-2-pentanone and absorption properties of film were measured. The influence on the difference of absorption maximum from azo-metal chelates to their ligands by diazo components, coupling components and metal ions was studied. [Copyright &y& Elsevier]

Flexible organic cathodes with 3,4,9,10-perylenetetracarboxylic diimide (PDI) as the active component, carbon black (CB) as the conductive agent and thermoplastic polyurethane (TPU) as the elastomeric matrix are obtained in this work via a solution-based phase inversion approach. In the resulting PDI/CB/TPU cathodes, the mass ratios of the three components manifest profound influences on their composition, flexibility, conductivity and lithium storage behavior. The integrated PDI/CB/TPU cathode with optimized ratio can deliver impressive rate capability and good cycling stability in lithium ion batteries (LIBs). More importantly, the full LIBs with PDI/CB/TPU cathode and carbon cloth anode exhibit excellent electrochemical performances, which show no decay even at bending states, demonstrating the appealing prospects of the solution-processed organic cathodes in wearable secondary batteries. Obtained from a solution-based phase inversion approach, the flexible PDI/CB/TPU cathodes manifest excellent electrochemical performances and good mechanical stability in lithium ion batteries. Image 1 [ABSTRACT FROM AUTHOR]

An acid-pasting approach is developed in this work to prepare the composites of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and carbon black (CB) by mixing both components in concentrated sulfuric acid. Different from the traditional powder processing, the solution-based fabrication strategy easily renders the effective combination of PTCDA and CB in the resultant CB/PTCDA composites, thus greatly improving their electrochemical performances. As the results, the composite with 20 wt% PTCDA shows excellent rate performances as the cathode material for both lithium ion battery (88 mAh g −1 at 5000 mA g −1 ) and sodium ion battery (100 mAh g −1 at 1000 mA g −1 ). As a facile and efficient processing strategy, the acid-pasting approach is expected to have wide application in the fabrication of organic electrodes in secondary batteries. [ABSTRACT FROM AUTHOR]

In this work, a facial in-situ polymerization strategy is developed for the first time to fabricate the composites of polyimide and carbon black (PI/CBs) by the condensation of 1,2,4,5-benzenetetracarboxylic anhydride and p -phenylenediamine with the presence of carbon black. This composition method can effectively suppress the crystallization of PI and thus allows the sufficient contact of PI and carbon black. As the cathode material in LIBs, the PI/CB composite manifests an extraordinary capacity of 182 mAh g −1 at 0.1 A g −1 , close to the theoretical value of PI. Moreover, the capacity of the PI/CB composite can be retained as 116 m Ah g −1 even at an ultrahigh current density of 10 A g −1 , outperforming the recently reported polymer LIB cathodes. Under the same conditions, the mechanical mixture of highly crystallized PI sheets and carbon black shows a much poorer performance. The approach demonstrated herein is expected to be further applied as an effective processing method to build up high performance electrodes with organic species in secondary batteries. [ABSTRACT FROM AUTHOR]

The design versatility and performance advantages render supercapacitors (SCs) the highly appealing candidates for the energy storage units in flexible devices. For this purpose, a flexible electrode with high capacitance and excellent mechanical stability is essential. Herein, the facile fabrication strategy towards flexible SC electrodes with polyaniline (PANI) nanowires loading on nitrogen-doped carbon coated SS mesh (PANI/N-C/SS) is developed via a simple hydrothermal carbonization process and the following deposition of PANI. Derived from glucose and dicyandiamide, the nitrogen-doped carbon layer can effectively improve the contract of the SS substrate and PANI. The resultant PANI/N-C/SS electrode delivers a high areal capacitance of 624 mF cm −2 at 0.05 mA cm −2 . With a large size of 40 cm 2 , the solid-state symmetric capacitor based on PANI/N-C/SS still possesses a capacitance of 122.6 mF cm −2 , corresponding to a high energy density of 0.22 mWh cm −2 . [ABSTRACT FROM AUTHOR]

There are accurate but inconclusive data on the association of interleukin (IL) 10 polymorphisms with sustained virological response (SVR) in chronic hepatitis C (CHC). This meta-analysis aimed to derive a more precise estimation of the effects of IL10 gene polymorphisms (-1082G/A, -819C/T, -592C/A) and their haplotypes on SVR in CHC patients receiving pegylated interferon alpha (PEG-IFN-a) plus ribavirin. Literature search was conducted up to Jan., 2016, in PubMed, EMBASE and ISI Web of Science electronic databases. Statistical analyses were performed by STATA11.0 software, with odds ratios (ORs) and their 95% confidence intervals (CIs). A total of 14 studies involving 1687 CHC cases met the inclusion criteria. Analyses were stratified either by ethnicity or genotype of hepatitis C virus (HCV). The results indicated that IL10 -1082A/G was associated with a significantly decreased SVR rate based on the heterozygous model (OR: 0.662, 95% CI: 0.467–0.938) and dominant model (OR: 0.648, 95% CI: 0.440–0.955). Similar results were found in the Egyptian and HCV-4 genotype in all gene models except the recessive model. Moreover, we observed that IL10 -819T allele carriers was associated with a significantly increased SVR in the Caucasian population (OR: 1.380, 95% CI: 1.018–1.871). However, we did not detect any significant association of the -592C/A polymorphism or haplotypes with SVR in the total or subgroup populations. In conclusion, IL10 -1082GG genotype and -1082G allele were associated with decreased SVR rate in CHC patients, especially for the Egyptian and HCV-4 genotype. Moreover, IL10 -819T allele was more likely to get SVR in the Caucasian population. [ABSTRACT FROM AUTHOR]

Hierarchically porous hybrids of strongly coupled nitrogen-doped porous carbons and graphene aerogel (NPC-GA) are fabricated through the solid-state oxidation polymerization and carbonization of m -phenylenediamine on the interconnected macroporous frameworks of GA. The hierarchically porous hybrids provide abundant storage sites and short transport paths for electrolyte ions. By adjusting the pyrolysis temperature, the specific surface areas and nitrogen content of NPC-GA can be easily modified, further influencing the electrochemical performance of the hybrids. In a three-electrode system, NPC-GA electrode shows high specific capacitance of 608 F g −1 at 0.1 A g −1 in 1 M H 2 SO 4 . An all-solid-state flexible supercapacitor based on NPC-GA delivers superior energy density (12.4 Wh Kg −1 ) and power density (2432 W Kg −1 ) as well as good cycling stability (92% specific capacitance retention after 10 000 cycles). [ABSTRACT FROM AUTHOR]

Excessive price and scarcity of Pt species make it very necessary to enhance the atom utilization and catalytic efficiency of Pt catalysts for implementing their industrial practicality. Here, natural cotton is adopted as the precursor to in-situ support well-dispersed and uniform-sized Ni nanoparticles, which then work as nanoislands to effectively deposit single-atom Pt via the galvanic replacement reaction. On the resulting fibrous carbon matrix, the monocrystalline Ni particles are verified to tightly anchor isolated Pt atoms to form the alloyed PtNi nanoparticles. In the 4-nitrophenol (4-NP) reduction to 4-aminophenol (4-AP), the catalytic activity of the bimetallic PtNi/C catalyst with the low Pt loading (0.81%) maximally reaches 25 times as high as the primary Ni/C product. Simulated calculations demonstrate that the single-atom Pt centers on PtNi nanoparticles rapidly capture and split H 2 molecules, while Ni atoms strongly adsorb 4-NP molecule to activate the -NO 2 group. Therefore, the trapped H atom could easily attack the -NO 2 and reduce 4-NP. Cotton is utilized to in-situ prepare well-dispersed and uniform-sized PtNi/C bimetallic catalysts with the superior activity in the 4-nitrophenol reduction. [Display omitted] • Natural cotton has been utilized for fabricating the Ni/C catalyst. • Ni nanoparticles work as nanoislands to deposit single-Atom Pt, forming PtNi nanoparticles. • The PtNi/C catalyst exhibits a great catalytic performance for reduction of 4-NP. • Catalytic mechanism of the PtNi/C bimetallic catalyst has been explored. [ABSTRACT FROM AUTHOR]

In this work, the composites of nitrogen-doped graphene framework and Co 3 O 4 nanoparticles with adjustable morphologies (NG/Co 3 O 4 ) were fabricated via a surfactant-assisted hydrothermal route for first time. Three different surfactants including triblock copolymer F127, cetyltrimethyl ammonium bromide and sodium dodecyl sulfate are involved in the hybrid-assembly of graphene oxide, o -phthalonitrile and cobalt acetate in water/ethanol. Among the obtained samples, the one using F127 (NG/Co 3 O 4 -F127) manifests the most homogeneous distribution of Co 3 O 4 NPs with the size of ∼ 15 nm in the macropore-walls formed by NG. As the anode material in lithium ion battery (LIB), NG/Co 3 O 4 -F127 exhibits excellent electrochemical performance, which is superior to the other composites and most of the previously reported Co 3 O 4 based anode materials in LIBs. [ABSTRACT FROM AUTHOR]

In this work, a novel strategy to fabricate ternary MoS 2 /SiO 2 /graphene hybrids (MSGs) was developed by incorporating amorphous SiO 2 with MoS 2 and graphene nanosheets. Serving as anode material in lithium ion batteries, the inert silica component can effectively prevent the pulverization caused by the inner-plane volume expansion of MoS 2 . It turns out that MSGs with ∼40 wt% of SiO 2 and ∼42 wt% of MoS 2 manifest the capacity stabilized at 1060 mAh g −1 for more than 100 cycles at the current density of 0.1 A g −1 . Further, this MSG electrode maintains the specific capacity of 580 mAh g −1 at an ultrahigh current density of 8 Ag −1 , which outperforms those of the reported MoS 2 and MoS 2 /graphene hybrids. [ABSTRACT FROM AUTHOR]

Abstract: The development of metal-free catalyst for oxygen reduction reaction (ORR) is one of the most challenging tasks in fuel cells. Heteroatom doped graphenes have been recognized as the promising candidate. In this work, we have developed a one-pot hydrothermal approach towards three-dimensional nitrogen and sulfur co-doped graphene frameworks (N/S-GFs) employing graphene oxide and ammonium thiocyanate as the precursors. N/S-GFs manifest excellent catalytic behavior with mainly four electron transfer pathway in ORR in alkaline condition. [Copyright &y& Elsevier]

An acid-assisted vacuum filtration approach is developed in this work to fabricate perylene diimide (PDI) and single wall carbon nanotube (SWCNT) based organic lithium ion battery (LIB) cathodes by using concentrated sulfuric acid (H 2 SO 4) as the solvent. PDI and SWCNT can be readily dispersed in H 2 SO 4 by the protonation of their aromatic frameworks, thus rendering the effective combination of them in the acidic solution. The resulting PDI/SWCNT films are highly appealing flexible cathodes for LIBs by associating the intriguing electrochemical activity of PDI with the excellent electric conductivity and mechanical stability of SWCNT. Either with lithium foils or pre-lithiated carbon clothes as the anodes, the LIBs with PDI/SWCNT cathodes can deliver highly stable electrochemical performances in terms of rate capability and cycling stability. The PDI/SWCNT cathodes also have very good mechanical stability, enabling the LIBs based on them to reserve the battery performances at different bending states. The excellent electrochemical stability of the PDI/SWCNT cathodes is attributable to the acidic solution based processing method, which is expected to be expanded in the electrode fabrication of various organic secondary batteries with π-conjugated components. An acid-assisted vacuum filtration approach is developed in this work to fabricate perylene diimide (PDI) and single wall carbon nanotube (SWCNT) based flexible lithium ion battery (LIB) cathodes by using concentrated sulfuric acid as the solvent. The LIBs with the PDI/SWCNT cathodes manifest very stable electrochemical performances, attributable to the acidic solution based processing method. Image 1 • An acid-assisted vacuum filtration approach is developed to produce PDI/SWCNT cathodes. • PDI/SWCNT cathodes can deliver high capacities at high current densities. • LIBs with PDI/SWCNT cathodes show highly stable electrochemical performances. • LIBs with PDI/SWCNT cathodes also have very good flexibility. [ABSTRACT FROM AUTHOR]