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Conventional TiO2/N719 photoanodes often suffer from the limited visible light absorption (450–500 nm) and the serous recombination of photo-generated carries (e−/h+)/electrolyte ions (I3−), accordingly outputting a low photoelectronic conversion efficiency (PCE). In this work, a type of strawberry-like TiO2/NiTiO3 (NTO) nanospheres was designed via a simple hydrothermal method. In this design, the NTO quantum dots (QDs) with size of several nanometers were decorated on the surface of TiO2 nanospheres. This TiO2/NTO nanostructure can not only enhance the visible light absorption of the TiO2/N179 photoanodes but also improve the separation of photo-generated carriers and depress the recombination of e−/h+ and I3−. Thus, the optimal TiO2/NTO/N719 dye-sensitized solar cells (DSSCs) achieved greatly improved Jsc and Voc, both of which result into a 32.8%-improved PCE compared to the TiO2/N719 ones. These improvements could be due to the decreased charge transfer resistance at the photoanode/electrolyte interface (Rct2) and the increased electron lifetime (τn) caused by TiO2/NTO hetero-interface. In addition, the optimization on NTO QDs indicates that the density of QDs main affects the τn, and the size of QDs affects with Rct2. Moderate density and size (ca. 5 nm) of QDs can optimize the photoelectronic performances of DSSCs. [ABSTRACT FROM AUTHOR]

[Display omitted] Carbon nanotubes (CNTs) are often used to settle down the sluggish reaction kinetics in lithium–sulfur batteries (LSBs). However, the self-aggregation of CNTs often makes them fail to effectively inhibit the shuttling effect of soluble lithium polysulfide (LiPS) intermediates. Herein, a type of ultra-stable carbon micro/nano-scale interconnected "carbon cages" has been designed by incorporating polar acid-treated carbon fibers (ACF) into three-dimensional (3D) CNT frameworks during vacuum filtration processes. Results show that the ACF-CNT composite frameworks possess a reinforced-concrete-like structure, in which the ACFs can well work as the main mechanical supporting frames for the composite electrodes, and the oxygen-containing functional groups (OFGs) formed on them as cross linker between ACFs and CNTs. Benefitted from this design, the ACF-CNT/S cathodes deliver an excellent rate capability (retain 72.6% at 4C). More impressively, the ACF-CNT/S cathodes also show an ultrahigh cycling stability (capacity decay rate of 0.001% per cycle over 350 cycles at 2C). And further optimization suggests that the suitable treatment on CFs could balance the chemical adsorption (OFGs) and physical confinement (carbon cages), leading to fast and durable electrochemical reaction dynamics. In addition, the assembled soft-pack LSBs further show a high dynamic bending stability. [ABSTRACT FROM AUTHOR]

Due to the harsh operating environment and ultralong operating hours of wireless sensor networks (WSNs), node failures are inevitable. Ensuring the reliability of the data collected by the WSN necessitates the utmost importance of diagnosing faults in nodes within the WSN. Typically, the initial step in the fault diagnosis of WSN nodes involves extracting numerical features from neighboring nodes. A solitary data feature is often assigned a high weight, resulting in the failure to effectively distinguish between all types of faults. Therefore, this study introduces an enhanced variant of the traditional belief rule base (BRB), called the belief rule base with adaptive attribute weights (BRB-AAW). First, the data features are extracted as input attributes for the model. Second, a fault diagnosis model for WSN nodes, incorporating BRB-AAW, is established by integrating parameters initialized by expert knowledge with the extracted data features. Third, to optimize the model's initial parameters, the projection covariance matrix adaptive evolution strategy (P-CMA-ES) algorithm is employed. Finally, a comprehensive case study is designed to verify the accuracy and effectiveness of the proposed method. The results of the case study indicate that compared with the traditional BRB method, the accuracy of the proposed model in WSN node fault diagnosis is significantly improved. [ABSTRACT FROM AUTHOR]

Due to the harsh operating environment and ultralong operating hours of wireless sensor networks (WSNs), node failures are inevitable. Ensuring the reliability of the data collected by the WSN necessitates the utmost importance of diagnosing faults in nodes within the WSN. Typically, the initial step in the fault diagnosis of WSN nodes involves extracting numerical features from neighboring nodes. A solitary data feature is often assigned a high weight, resulting in the failure to effectively distinguish between all types of faults. Therefore, this study introduces an enhanced variant of the traditional belief rule base (BRB), called the belief rule base with adaptive attribute weights (BRB-AAW). First, the data features are extracted as input attributes for the model. Second, a fault diagnosis model for WSN nodes, incorporating BRB-AAW, is established by integrating parameters initialized by expert knowledge with the extracted data features. Third, to optimize the model's initial parameters, the projection covariance matrix adaptive evolution strategy (P-CMA-ES) algorithm is employed. Finally, a comprehensive case study is designed to verify the accuracy and effectiveness of the proposed method. The results of the case study indicate that compared with the traditional BRB method, the accuracy of the proposed model in WSN node fault diagnosis is significantly improved. [ABSTRACT FROM AUTHOR]

Herein, we elucidate a novel strategy to introduce the electrostatic interaction by adding the ferroelectric phase PVDF through the thermal assisted polarization process. Benefitting from strong electrostatic force from β phase PVDF to PS− and Li+ ions, the LSBs show outstanding rate and cycling stability. To our knowledge, rarely reported about introducing electrostatic forces in binders to inhibit the shuttling of polysulfides. Furthermore, the enhancement mechanism for the cathodes' electrochemical performances was also discussed in details. [Display omitted] • Ferroelectric effect was introduced by converting α-PVDF to β one via thermal polarization. • The polarized β-PVDF has an improved conductance and an enhanced chemisorption to LiPSs. • The electric field from β-PVDF can help the anchoring of the PS− ions and the diffusing of Li+ ions. • The LSBs can show a highly-improved rate capability, as well as an ultrahigh cycling stability. Electric field from ferroelectric materials was often applied to energy-storage devices to enhance their electrochemical reaction kinetics via the electrostatic interaction. However, traditional ferroelectric materials are difficult to be used commercially for their insulation. Herein, we elucidate a novel strategy to introduce the electrostatic interaction by polarizing the polyvinylidene fluoride (PVDF) binder used in the C/S cathodes for lithium-sulfur batteries. In particular, we show both experimentally and theoretically how an external electric field from β -phase PVDF induces unprecedented performance and stabilities. Density functional theory calculation results indicate that the polarized topological β -phase PVDF possesses not only an strong built-in electric field and an improved conductance that benefits both the deposition of LiPSs and the transport of Li+ ions, but also an enhanced adsorption capability to polysulfide ions. As a result, the specific capacity was improved by over 60 %, the rate capability (from 0.1 to 2.0 C) was enhanced by 138 %, and the capacity decay rate (1000 cycles at 1.0 C) largely decreases from 0.059 % to 0.038 % per cycle. Besides, the enhancement mechanism of Li 2 S deposition by electrostatic interaction has also been explored. This research would provide some new insight into the ferroelectric enhanced design of high-performance energy-storage devices. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) are still limited by the shuttle of lithium polysulfides (LiPS) and the slow Li−S reaction. Herein, we demonstrate that when using cobalt sulfide as a catalytic additive, an external magnetic field generated by a permanent magnet can significantly improve the LiPS adsorption ability and the Li−S reaction kinetics. More specifically, the results show both experimentally and theoretically how an electron spin polarization of Co ions reduces electron repulsion and enhances the degree of orbital hybridization, thus resulting in LSBs with unprecedented performance and stability. Under an external magnetic field, LSBs with 0.0084 % per cycle decay rate at 2 C during 8150 cycles are produced. Overall, this work not only demonstrates an effective strategy to promote LiPS adsorption and electrochemical conversion in LSBs at no additional energy cost but also enriches the application of the spin effect in the electrocatalysis fields. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) are still limited by the shuttle of lithium polysulfides (LiPS) and the slow Li−S reaction. Herein, we demonstrate that when using cobalt sulfide as a catalytic additive, an external magnetic field generated by a permanent magnet can significantly improve the LiPS adsorption ability and the Li−S reaction kinetics. More specifically, the results show both experimentally and theoretically how an electron spin polarization of Co ions reduces electron repulsion and enhances the degree of orbital hybridization, thus resulting in LSBs with unprecedented performance and stability. Under an external magnetic field, LSBs with 0.0084 % per cycle decay rate at 2 C during 8150 cycles are produced. Overall, this work not only demonstrates an effective strategy to promote LiPS adsorption and electrochemical conversion in LSBs at no additional energy cost but also enriches the application of the spin effect in the electrocatalysis fields. [ABSTRACT FROM AUTHOR]

Abstract: Based on the cement particles distribution characteristic of interfacial transition zone (ITZ) in cement-based composite materials and modified powers model, a numerical calculation model is proposed to predict the porosity distribution, average porosity and effective diffusion coefficient of chloride ions in ITZ. The model takes into account the influence of water-to-cement ratio, the thickness of ITZ and the degree of hydration on the porosity distribution of ITZ. The results show that the ratio of the capillary porosity of ITZ to that of bulk cement paste (ϕITZ /ϕB ) and the ratio of the diffusion coefficients of chloride ions in ITZ to that in bulk cement paste (DITZ /DB ) are almost consistent with those in published papers. In addition, the results of numerical calculation further confirm the diffusion coefficient of ITZ is 10 times as much as that of bulk cement paste. [Copyright &y& Elsevier]

Discusses estimation and prediction in a Markov renewal model where intensities of the one-step transitions follow a Cox regression model with baseline hazards and covariates depending on the backward recurrence time. Review of related literature; Inferences; Data source.

Ordered array structures will greatly reduce the stress formation in wearable electric devices during dynamic bending operation. In this work, highly flexible TiN-based fiber counter electrodes (FCEs) were designed via a post-ammonization treatment on the hydrothermally grown TiO2 nanowire arrays. Results show that the obtained TiN nanorod arrays (NRAs) are well aligned with a diameter of 200–320 nm and a length of several hundred nanometers to ∼1 μm. Moreover, fiber-shaped dye-sensitized solar cells assembled using TiN FCEs showed the maximum photoelectric conversion efficiency (PCE) of 5.69%, which is 16.3% higher than that of the ones based on Pt FCEs. Analysis indicated that this enhancement in PCE could be mainly due to the better electrochemical catalytic activity of TiN NRAs. Furthermore, the optimizations of the nanoscale morphologies of TiN NRAs suggest that both small diameters and large lengths can benefit the PCE and the dynamic bending stability, while the diameters show a major influence on them. The optimal FCEs show an ultralow decay rate of 0.017‰ per bending cycle. [ABSTRACT FROM AUTHOR]

It was demonstrated that the electrochemical performance enhancements in KOH-activated carbon materials should be mainly due to the created polar oxygen-containing functional groups (OFGs, such as such as C–O, C O, –OH, and O–C O), while the role of each OFGs on the electrochemical enhancements is still unclear. In this work, KOH activation treatments were systematically conducted on carbon nanotubes (CNTs) to explore the role of each OFG on the performance enhancements of Li–S batteries (LSBs). Results showed that the capacity of activated-CNT-sulfur (a-CNT-S) cathodes is 33% higher than that of the pristine CNT-S cathodes, and their rate capability and cycling stability are also enhanced. And the electrochemical analysis combining with Fourier transform infrared spectroscopy indicated that the formed C–O bonds are the real factor for the enhanced electrochemical performances of a-CNT-S cathodes. Furthermore, the optimal activation conditions on CNT-based cathodes for LSBs were optimized to be 10 min at 700 °C. Image 1 • KOH activated CNTs (a-CNTs) were used as the sulfur hosts for Li-S batteries. • FTIR tests indicated a-CNT-S cathodes' performances are linearly dependent on the C−O bonds. • The optimal activation conditions on CNT hosts were determined (10 min, 700 °C). [ABSTRACT FROM AUTHOR]

The partially-embeddedMnO/ECNF composite electrodes exhibit an much lower decay rate (0.004‰ per cycle for 20,000 cycles) than those of the traditionnal MnO 2 /ECNF ones (decay rate of 0.015‰ per cycle for 8000 cycles). • The MnO nanocubes were partially inserted into the ECNF skeletons to make a strong joint between them. • The h-MnO/ECNF electrodes exhibit a super excellent cycling stability. • The h-MnO/ECNF electrodes can well work within −1 V to +1 V. Post-grown hierarchical pseudocapacitive nanostructures often suffer from their bad long-term cycling stability. In this work, a type of hierarchical partially-embedded MnO nanocube/electrospun carbon nanofiber composites (pe-MnO/ECNFs) was designed. Results show the MnO nanocubes are partially embedded into the ECNFs skeletons, showing a strong joint between them. The pe-MnO/ECNFs electrodes exhibit a high specific capacitance of 146 F g−1 (to the whole electrode mass) at scan rate of 5 mV s−1, and an ultralow decay rate of 0.004‰ per cycle for 20,000 cycles at 10 A g−1, which is much better than those of the MnO 2 /ECNF ones (96 F g−1, decay rate of 0.015‰ per cycle). Furthermore, the assembled flexible symmetric supercapacitors show an high energy density of 6.8 W h kg−1, a high dynamic bending stability, and a robust long cycling stability (low decay rate of 0.003‰ per cycle for 6000 cycles at 1 A g−1). [ABSTRACT FROM AUTHOR]

The novel AgCl/Ag2SO3 hybrids as an efficient photocatalyst had been fabricated by an in situ synthetic method. The correlations between the structure and the photocatalytic properties of the as‐fabricated hybrids were analyzed. Experimental results exhibited that with increasing the amount of Ag2SO3, the degradation rate of the as‐obtained samples was firstly increased and then decreased under the visible light irradiation. When the mass ratio of AgCl to Ag2SO3 was 1:2, in 30 min, it displayed the highest degradation rate of 99.2% for rhodamine‐B, which was obviously higher than 46.1, 60.5, and 14.6% of pure AgCl, Ag2SO3, and TiO2 (P25), respectively. Similar results could be found in degradation of methyl orange. It had the maximum of 97.4% in 90 min, which was higher than 55.2, 48.7, and 12.7% of pure AgCl, Ag2SO3, and P25, respectively. Moreover, the as‐prepared hybrids possessed the enhanced separation and transfer of photo‐generated electron–hole pairs compared to the pure samples. In addition, the holes and superoxide radicals played the dominant role and the hydroxyl radicals played the secondary role during the process of photocatalytic degradation. [ABSTRACT FROM AUTHOR]

This study compares the effects of the cancer experience on various aspects of marital and sexual Functioning (e.g., communication, emotional support, body image, sexual satisfaction and frequency) for two groups of tong-term cancer survivors (testicular cancer and Hodgkin's disease) and their spouses. Comparisons between the two patient groups showed significantly more survivors of Hodgkin's disease than testicular cancer reporting the emergence of special issues and changes in the marital relationship. No differences emerged between the spouse groups on sexual functioning variables; however, spouses of survivors of Hodgkin's disease were more likely than spouses of survivors of testicular cancer to report the development of special issues and communication difficulties. A substantial proportion of both survivor groups disclosed negative changes in body image and sexual frequency. Majorities of both survivors and spouses acknowledged that the illness had drawn them closer together. When representative marital/sexual functioning variables were used to predict Family Environment Scale (FES) scores for survivors and for spouses, changes in the spouse's importance, influence of the illness on the relationship, and changes in sexual frequency emerged as significant predictors. The clinical significance of long-term changes in marital and sexual functioning for the couple and the need for therapeutic interventions are discussed. [ABSTRACT FROM AUTHOR]

The In2.77S4/SrCO3 heterojunction photocatalyst had been prepared by one-step hydrothermal method. X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectrometry, UV-Vis diffuse reflectance spectroscopy and electrochemical impedance spectroscopy were used to analyze the structure, morphology, chemical compositions, optical properties and charge carrier behaviors of the as-prepared In2.77S4/SrCO3 hybrids, respectively. Experimental results revealed the SrCO3 could obviously improve the recyclability and photocatalytic activities of In2.77S4 nanosheets for both methyl orange and tetracycline oxidation under visible light. The photocatalytic degradation efficiency of the as-obtained In2.77S4/SrCO3 hybrids was first increased and then decreased with increasing the molar ratio of Sr(NO3)2 to In(NO3)3·4.5H2O. When it was 0.4:1, that of the as-prepared hybrids with the band gap of 1.63 eV reached the maximum of 96.0% in 30 min for methyl orange and 82.7% in 20 min for tetracycline. These were higher than 88.0% and 40.0% of In2.77S4 nanosheets as well as 0.8 and 1.8% of SrCO3 particles, respectively. After three cycles, its photocatalytic efficiency still possessed 92.7% for methyl orange and 80.3% for tetracycline, which were much higher than 35.3% and 11.3% of In2.77S4 nanosheets. Moreover, the possible photocatalytic degradation mechanism of the In2.77S4/SrCO3 hybrids was also proposed. [ABSTRACT FROM AUTHOR]

The In2.77S4 microspheres had been firstly fabricated by using polyethylene glycol (PEG) as the morphological modifier and then used to hybridize with In(OH)3 nanocubes by a simply depositional method. The structure, optical properties, morphology, chemical compositions, and charge carrier behaviors of the as-prepared In2.77S4/In(OH)3 composites were characterized, respectively. The methyl orange, tetracycline, rhodamine B, and Cr(VI) dilute solution were selected to evaluate their photocatalytic activities. Experimental results showed that In(OH)3 nanocubes could improve the photocatalytic activity and recyclability of the In2.77S4 microspheres under the visible light irradiation. With the usage of In(OH)3 increased, the photocatalytic efficiency of the hybrids was firstly increased and then decreased. When the mass ratios of In2.77S4 to In(OH)3 were 6:2, it reached the maximum of 100% in 15 min for methyl orange, obviously higher than 67.4% of In2.77S4 and 1.1% of In(OH)3. Meanwhile, it could also oxidize 85.6% of tetracycline in 20 min, 97.8% of rhodamine B in 7.5 min, and reduce 92.9% of Cr(VI) in 30 min under the visible light irradiation. Moreover, it could still degrade 91.7% of methyl orange solution after 3 cycles, which was much higher than 40.7% of In2.77S4 microspheres. In addition, the possible mechanism of enhancing photocatalytic properties was proposed. [ABSTRACT FROM AUTHOR]