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The restricted arc-connectivity is an effective assessment of the reliability of directed networks, which is an extended notion of arc-connectivity. Let D be a digraph. An arc set S of D is a restricted arc-cut of D if D − S has a strong connected component D ′ such that | V (D ′ ) | ≥ 2 and D − V (D ′ ) contains an arc. The digraph D is called λ ′ -connected if there exists a restricted arc-cut in D. The restricted arc-connectivity λ ′ (D) of a λ ′ -connected digraph D is the minimum cardinality over all restricted arc-cuts. We can get a unidirectional star graph by orienting the star graph with Day-Tripathi orientation. In this paper, we first show that the restricted arc-connectivity of the n -dimensional unidirectional star graph is n − 2 when n is odd and n − 3 when n is even for n ≥ 4. As a consequence, we prove that n -dimensional unidirectional star graph is super- λ when n ≥ 3 and n ≠ 4. [ABSTRACT FROM AUTHOR]

Titanium alloys are widely used in various structural materials due to their lightweight properties. However, the low wear resistance causes significant economic losses every year. Therefore, it is necessary to implement wear-resistant protection on the surface of titanium alloys. In this study, four types of in situ composite ceramic coatings with two-layer gradient structures were prepared on a Ti-6Al-4V (TC4) substrate using laser cladding. In order to reduce the dilution rate, a transition layer (Ti-40SiC (vol.%)) was first prepared on TC4 alloy. Then, a high-volume-fraction in situ composite ceramic working layer (Ti-xFe-80SiC (vol.%)) with different contents of Fe-based alloy powder (x = 0, 5, 10 and 15 vol.%) was prepared. The working surface of Ti-40SiC (TL) exhibited a typical XRD pattern of Ti, TiC, Ti5Si3, and Ti3SiC2. In comparison, both Ti-80SiC (WL-F0) and Ti-5Fe-80SiC (WL-F5) exhibited similar phase compositions to the TL coating, with no new phase identified in the coatings. However, the TiFeSi2 and SiC phases were presented in Ti-10Fe-80SiC (WL-F10) and Ti-15Fe-80SiC (WL-F15). It is proven that the addition of the Fe element could regulate the in situ reaction in the original Ti-Si-C ternary system to form the new phases with high hardness and good wear resistance. The hardness of the WL-F15 (1842.9 HV1) is five times higher than that of the matrix (350 HV1). Due to the existence of self-lubricating phases such as Ti5Si3 and Ti3SiC2, a lubricating film was presented in the WL-F0 and WL-F5 coatings, which could block the further damage of the friction pair and enhance the wear resistance. Furthermore, a wear-transition phenomenon was observed in the WL-F10 and WL-F15 coatings, which was similar to the friction behavior of structural ceramics. Under the load of 10 N and 20 N, the wear volume of WL-F15 coating is 5.2% and 63.7% of that in the substrate, and the depth of friction of WL-15 coating is only 14.4% and 80% of that in the substrate. The transition of wear volume and depth can be attributed to the wear mechanism changing from oxidation wear to adhesive wear. [ABSTRACT FROM AUTHOR]

The pursuit of an advanced functional coating that simultaneously combines high hardness, wear resistance, and superior electrical conductivity has remained an elusive goal in the field of copper alloy surface enhancement. Traditional solid solution alloying methods often lead to a significant increase in electron scattering, resulting in a notable reduction in electrical conductivity, making it challenging to achieve a balance between high hardness, wear resistance, and high conductivity. The key lies in identifying a suitable microstructure where dislocation motion is effectively hindered while minimizing the scattering of conductive electrons. In this study, a novel Cu-MoSi2 coating was successfully fabricated on a CuCrZr alloy surface using the coaxial powder feeding high-speed laser cladding technique, with the addition of 10–30% MoSi2 particles. The coating significantly enhances the hardness and wear resistance of the copper substrate while maintaining favorable electrical conductivity. As the quantity of MoSi2 particles increases, the coating's hardness and wear resistance gradually improve, with minimal variance in conductivity. Among the coatings, the Cu-30%MoSi2 coating stands out with the highest hardness (974.5 HV0.5) and the lowest wear amount (0.062 mg/km), approximately 15 times the hardness of the copper base material (65 HV0.5) and only 0.45% of the wear amount (13.71 mg/km). Additionally, the coating exhibits a resistivity of 0.173 × 10−6 Ω·m. The extraordinary hardness and wear resistance of these coatings can be attributed to the dispersion strengthening effect of MoxSiy particles, while the high electrical conductivity is due to the low silicon content dissolved into the copper from the released MoSi2 particles, as well as the rapid cooling rates associated with the high-speed laser cladding process. [ABSTRACT FROM AUTHOR]

In order to ensure the normal operation and safety at work of electronic equipment, the research on thermal management of electronic components has continued increasing in recent years. Graphite film produced with polyimide (PI) as the substrate is an important thermal conductivity material, and its thermal conductivity can be improved through doping modification. Compared with solid thermal conductive filler, ionic liquid has better compatibility with polyimide matrix, and has been commonly used in gas separation membrane, colorless polyimide (CP1) and other applications. This article used 4, 4'-diaminobenzoylanilide (DABA) and 3, 3', 4, 4'-biphenyltetracarboxylic dianhydride (BPDA) as monomers, and modified PI films by using l-ethyl-3-methylimi-dazolium bis[(trifluoromethyl)sulfonyl]imide(lL) that had the characteristic of multiple hydrogen bond sites. Then, high thermal conductivity graphite film was prepared by graphitization. The research results show that when the 1L content is 5.0 wt%, the grain size of the graphite film is 78.417 nm, the degree of graphitization reaches 88%, and the thermal conductivity reaches 770 W/mK, which is 1.53 times that of the pure PI cornerstone ink film. [ABSTRACT FROM AUTHOR]

Electric energy routers (EERs) can effectively deal with the energy management issues caused by the access of multi-sources and multi-loads. Different from the energy transmission form in the existing series architecture EER (SA-EER) for low-voltage distribution networks, a new series-parallel architecture EER (SPA-EER) has the advantages of high-power transmission capability and reactive power flexible operation. However, if controller parameters change beyond their critical stability boundaries, SPA-EER will produce slow- and fast-scale bifurcation behaviors, which are manifested as low- and high-frequency oscillations of port voltages or port currents in varying degrees. To avoid the system instability caused by controller parameter changes, how to discriminate the stability regions of controller parameters for SPA-EER is a key research content in this paper. To this end, the stroboscopic mapping discrete model of SPA-EER system is first established, and system bifurcation behaviors are analyzed based on bifurcation theory. Furthermore, the critical stability boundaries of controller parameters are discriminated by using Jacobian matrix, root locus and bifurcation diagram. After that, a time delay feedback control (TDFC) is employed to suppress system bifurcation behaviors. Finally, the correctness of bifurcation analysis and the effectiveness of TDFC are verified by a hardware-in-the-loop (HIL) experimental platform. [ABSTRACT FROM AUTHOR]

Based on AR learning software, this study investigated whether students with positive academic emotion and negative academic emotion maintained consistent levels of attention and relaxation. In Study 1, 98 primary school students were selected and tested with the SUS scale after completing an AR learning module. In Study 2, 45 primary school students were selected to participate in a two-factor between-subjects experimental design. The results showed that (1) AR learning software has good usability, (2) there was a significant difference in gender — in the AR learning environment, girls' degree of relaxation was greater than that of boys, (3) in AR learning, the degree of attention and relaxation among students in the negative academic emotion group was higher than among those in the positive academic emotion group, but the difference did not reach a level of significance, which partly reflects the interest-based positive compensation trend of negative academic emotion. [ABSTRACT FROM AUTHOR]

Due to low cost and abundance, direct seawater splitting to produce hydrogen is an encouraging strategy to alleviate the consumption of fossil energy, while also avoiding freshwater stress. However, when natural seawater is utilized as the electrolyte, the catalysts on the cathode and anode of water splitting should not only have high activity to promote energy efficiency, but also have good stability and durability to resist the corrosion of chloride ions. Herein, a hierarchical carbon-based catalyst for hydrogen and oxygen evolution, ZIF-67/CF-1, was prepared by annealing a composite of ZIF-67 and carbon fiber (CF). It exhibits good electrocatalytic activity and stability for overall splitting in natural seawater and neutral PBS solution. Impressively, when an electrolyzer consisting of ZIF-67/CF-1||ZIF-67/CF-1 is applied to overall seawater splitting, the current density of 10 mA/cm2 is achieved with a drive voltage of 2.46 V, which is only 0.28 V higher than precious metal-based electrolyzer (Pt/C||IrO 2). Meanwhile, ZIF-67/CF-1 shows outstanding catalytic ability for oxygen reduction (E 1/2 = 0.84 V, Tafel slope = 66.9 mV/dec), also demonstrating its application potential in rechargeable batteries and fuel cells. A hierarchical carbon-based electrocatalyst (ZIF-67/CF-1) were developed for oxygen evolution on the anode and hydrogen evolution/oxygen reduction on the cathode. It owns good activity, stability and durability for hydrogen and oxygen evolution in natural seawater, and has been used as a bifunctional catalyst for overall seawater splitting in a two-electrode electrolyzer. Additionally, ZIF-67/CF-1 exhibits the high half-wave potential and small Tafel slope value for oxygen reduction in 0.1 M KOH. [Display omitted] • The hierarchical carbon-based catalysts for HER, OER and ORR were prepared. • ZIF-67/CF-1 exhibits good electrocatalytic ability for overall seawater splitting. • The current density of 10 mA/cm2 is achieved with a cell voltage of only 2.46 V. • The ORR catalytic performance of ZIF-67/CF-1 is comparable to that of Pt/C. • N-doped hierarchical carbon is beneficial to the electrocatalytic performance. [ABSTRACT FROM AUTHOR]

In this paper, a dual active bridge‐based unified power quality conditioner (DAB‐UPQC) is constructed to solve the bulky issue caused by a line‐frequency transformer (LFT) in conventional UPQC. Since there is no LFT, the constructed DAB‐UPQC is easier to realize modular manufacturing, which further increases the flexibility of system. After adding DAB, the UPQC will present two obvious changes as follows: (a) Almost all of the grid input current flows through the series converter, resulting in an increase in the current stress of switches in the series converter. (b) The dc link is allowed to contain both low‐ and high‐voltage amplitudes due to the voltage ratio of high‐frequency transformer in DAB. Considering these two changes, the operation behaviors of DAB‐UPQC are analyzed in detail, which has the valuable significance for designs of DAB, series and parallel converters. Additionally, the characteristics and implementation conditions of soft‐switching for DAB with single‐phase‐shift (SPS) modulation are analyzed and discussed, and the battery bank is integrated on the low‐voltage side of dc link to provide continuous power to the load in the event of the grid outage or failure. Finally, the operation performances of DAB‐UPQC under the conditions of grid voltage sag/swell, nonlinear load, and grid outage are verified by using a hardware‐in‐the‐loop (HIL) experimental platform. [ABSTRACT FROM AUTHOR]

To improve the wear resistance of high-strength and high-conductivity Cu–Cr–Zr alloys in high-speed and heavy load friction environments, coatings including Ni–Cu, Ni–Cu-10(W,Si), Ni–Cu–10(Mo,W,Si), and Ni–Cu–15(Mo,W,Si) (with an atomic ratio of Mo,W to Si of 1:2) were prepared using coaxial powder-feeding laser cladding technology. The microstructure and wear performance of coatings were chiefly investigated. The results revealed that (Mo,W)Si2 and MoNiSi phases are found in the Ni–Cu–10(Mo,W,Si) and Ni–Cu–15(Mo,W,Si) coating. WSi2 phases are found in the Ni–Cu–10(W,Si) coating. The degree of grain refinement in Ni–Cu–10(Mo,W,Si) was greater than that of the Ni–Cu–10(W,Si) coating after the effect of Mo. The excellent wear resistance and micro-hardness of the Ni–Cu–15(Mo,W,Si) coating were attributed to the increase in its dispersion phase, which were approximately 34.72 mg/km and 428 HV, 27.1% and 590% higher than the Cu–Cr–Zr substrate, respectively. The existence of silicide plays an important role in grain refinement due to the promotion of nucleation and the inhibition of grain growth. In addition, the wear mechanism transformed from adhesive wear in the Ni–Cu coating with no silicides to abrasive wear in the Ni–Cu–15(Mo,W,Si) coating with high levels of silicides. [ABSTRACT FROM AUTHOR]

This article presents an improved algorithm for identification of the excess loss statistical parameter to get more accurate prediction of multiple harmonic magnetic hysteresis and loss properties of grain-oriented silicon steel sheets. Magnetic hysteresis characteristics of a specimen are measured on a magnetic measurement platform. Static hysteresis property can be simulated accurately by the Preisach model. The excess loss field expression under multiple harmonic magnetizations is constructed based on an extraction algorithm for the statistical parameters of excess loss. According to the equivalence of loss separation and field separation, a new dynamic model is established. In the case of different multiple harmonic magnetizations, the magnetic hysteresis characteristics obtained by predictions are compared with the test results. Also, the influences of peaked flux density, harmonic order, and harmonic content upon the total iron loss are investigated. [ABSTRACT FROM AUTHOR]

This article presents an improved dynamic hysteresis model to predict magnetic hysteresis properties under high-frequency sinusoidal excitations. A new expression of magnetic field strength related to classical loss is derived and proposed to consider the effect of skin effect on the iron loss. The permeability related to statistical parameter is presented to establish the relationship between classical loss and excess loss. The introduction of shape factor provides a possibility for accurate prediction of dynamic loops at high frequency over a broad induction range. The accuracy of the proposed dynamic hysteresis model is verified by comparing the predicted results with the measured ones. In addition, the variation of loss components with frequency and peaked induction is analyzed. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting, metal-air batteries and fuel cells are the representatives of energy storage/conversion technology, which can solve the shortage of traditional fossil energy and environmental issues. However, under neutral conditions, especially in natural seawater, there is still a lack of catalysts with efficient catalytic activity and stability, which hinders the development of hydrogen production. We herein designed a facile strategy to fabricate an efficient and stable multifunctional carbon-based electrocatalyst, PMA@ZIF-67-C-AT, by carbonization and acid treatment of H 3 PMo 12 O 40 @ZIF-67 precursor. It not only performs good catalytic activity for oxygen evolution in 0.2 M phosphate buffer solution (PBS) and actual seawater, but also exhibits hydrogen evolution overpotential of 650 mV (j = 3 mA/cm2) in PBS and even as low as 570 mV (j = 10 mA/cm2) in seawater. Besides, it also displays excellent catalytic performance for oxygen reduction (E 1/2 at 0.83 V and the Tafel slope of 63 mV/dec). By investigating the composition and morphology of the materials, it was found that acid treatment changed the active components and carbon matrix of the catalysts, thus affecting the catalytic performance. A multifunctional carbon-based electrocatalyst, PMA@ZIF-67-C-AT, was successfully prepared by carbonization and acid treatment of H 3 PMo 12 O 40 @ZIF-67 precursor. It not only exhibits excellent catalytic performance for ORR in alkaline solution, but also has efficient catalytic activity and stability for HER and OER actual seawater. [Display omitted] • Multifunctional carbon-based catalyst derived from polyoxometalates and MOFs. • Efficient bifunctional catalyst for hydrogen and oxygen evolution in seawater. • Excellent ORR catalytic ability with a Tafel slope smaller than that of Pt/C. • The performance of catalyst is affected by active components and carbon matrix. [ABSTRACT FROM AUTHOR]

This article, titled "[Retracted] MicroRNA-379 suppresses cell proliferation, migration and invasion in nasopharyngeal carcinoma by targeting tumor protein D52," was published in the journal Experimental & Therapeutic Medicine in 2018. However, it has since been retracted due to concerns raised by a reader. The reader pointed out that certain data in the article's Transwell cell invasion assay were very similar to data published in another article by different authors at a different research institute. The authors were asked for an explanation but did not respond. The editor has apologized for any inconvenience caused. [Extracted from the article]

In 2020, Lin and Zhang proposed the concept of g -good-neighbor (respectively, g -good-in-neighbor, g -good-out-neighbor) connectivity of digraphs and their respective diagnosability under PMC model. In this paper, we establish some relationships between connectivity, diagnosability, g -good-neighbor connectivity and g -good-neighbor (respectively, g -good-in-neighbor, g -good-out-neighbor) diagnosability of strong digraph networks. As an application, we use these relationships to obtain g -good-out-neighbor and 1-good-neighbor (respectively, 1-good-in-neighbor) diagnosability of some well-known strong digraph networks. [ABSTRACT FROM AUTHOR]

Phase engineering of the electrode materials in terms of designing heterostructures, introducing heteroatom and defects, improves great prospects in accelerating the charge storage kinetics during the repeated Li+/Na+ insertion/deintercalation. Herein, a new design of Li/Na‐ion battery anodes through phase regulating is reported consisting of F‐doped SnO2‐SnS2 heterostructure nanocrystals with oxygen/sulfur vacancies (VO/VS) anchored on a 2D sulfur/nitrogen‐doped reduced graphene oxide matrix (F‐SnO2‐x‐SnS2‐x@N/S‐RGO). Consequently, the F‐SnO2‐x‐SnS2‐x@N/S‐RGO anode demonstrates superb high reversible capacity and long‐term cycling stability. Moreover, it exhibits excellent great rate capability with 589 mAh g−1 for Li+ and 296 mAh g−1 at 5 A g−1 for Na+. The enhanced Li/Na storage properties of the nanocomposites are not only attributed to the increase in conductivity caused by VO/VS and F doping (confirmed by DFT calculations) to accelerate their charge‐transfer kinetics but also the increased interaction between F‐SnO2‐x‐SnS2‐x and Li/Na through heterostructure. Meanwhile, the hierarchical F‐SnO2‐x‐SnS2‐x@N/S‐RGO network structure enables fast infiltration of electrolyte and improves electron/ion transportation in the electrode, and the corrosion resistance of F doping contributes to prolonged cycle stability. [ABSTRACT FROM AUTHOR]

Kava, the rhizomes and roots of Piper methysticum Forst, is a popular edible medicinal herb traditionally used to prepare beverages for anxiety reduction. Since the German kava ban has been lifted by the court, the quality evaluation is particularly important for its application, especially the flavokawains which were believed to be responsible for hepatotoxicity. Now, by employing two different standard references and four different methods to calculate the relative correction factors, eight different quantitative analyses of multicomponents by single‐marker methods have been developed for the simultaneous determination of eight major kavalactones and flavokawains in kava. The low standard method difference on quantitative measurement of the compounds among the external standard method and ours confirmed the reliability of the mentioned methods. A radar plot clearly illustrated that the contents of dihydrokavain and kavain were higher, whereas flavokawains A and B were lower in different kava samples. Only one of eight samples did not detect flavokawains that may be related to hepatotoxicity. In summary, by using different agents as an internal standard reference, the developed methods were believed as a powerful analytical tool not only for the qualitative and quantitative of kava constituents but also for the other multicomponents when authentic standard substances were unavailable. [ABSTRACT FROM AUTHOR]

Carbon-supported non-precious metal catalysts with highly exposed active sites have great potential for applications in the hydrogenation reduction of nitro compounds. Herein, a strategy for the preparation of carbon-supported Mo-based catalysts (Mo@C/MC) is proposed. Protein–Mo ion networks are first coated on the surface of microsphere carbons (MC). The coated MC employed as a precursor is then pyrolyzed to produce carbon-supported Mo-based catalysts. Notably, neither pore-forming agents nor post-treatment is required in the preparation of the catalyst. The active sites tend to disperse uniformly on the surface of the carbon matrix, facilitating the exposure of the active sites of the catalyst. The as-prepared catalyst Mo@C/MC shows high conversion (>99%) and selectivity (>98%) for the hydrogenation of nitro compounds under mild reaction conditions (100 °C, 5 bar H2). [ABSTRACT FROM AUTHOR]

A new algorithm for numerical identification of the static Preisach hysteresis model is proposed for more accurate estimation of dc-biasing hysteresis curves and hysteresis loss of the grain-oriented silicon steel sheet. Based on the experimental asymmetric major hysteresis loop under dc-biased magnetization, two sets of first-order reversal curves corresponding to ascending and descending branches, respectively, are numerically generated for construction of the Everett function. According to the equivalent field separation technique, a dynamic hysteresis model is established by parameter extraction of excess loss, and then used for simulation of dc-biasing dynamic hysteretic behaviors. The consistency between the simulated results and the measured ones demonstrates the effectiveness of the proposed method. The effect of dc bias on iron loss is analyzed as well. [ABSTRACT FROM AUTHOR]

Liver transplantation (LT) is the best choice for patients with end-stage liver diseases. In order to better understand pathophysiological alterations in LT, we aimed to identify potential hub genes and inhibitory compounds involved in the LT process. Four pairs of peripheral blood mononuclear cell (PBMC) samples of the LT recipients before and after surgery were collected and taken for transcriptome sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed for the screened differentially expressed genes (DEGs) between pre- and post-operation groups. Common DEGs were obtained from GO and KEGG enriched pathways, followed by protein-protein interaction (PPI) network construction, hub gene identification, module analysis, and structure-based virtual screening process (SBVS). Compared to the pre-operation stage, 4745 genes were down-regulated and 798 up-regulated after LT. GO analysis showed that the DEGs were enriched in ribosome-related translation regulation, and KEGG analysis indicated that infection and immune-related pathways and diseases were largely enriched. A large number of down-regulated DEGs were not only associated with ribosome-related pathways but also with the alterations of epigenetic modifications, in particular ubiquitination. Moreover, through the PPI network of 29 common genes from GO and KEGG-enriched pathways, 7 hub genes were identified, including PTEN, MYC, EIF2S1, EIF4EBP1, HSP90AB1, TP53, and HSPA8, which were mainly involved in the PI3K-AKT signaling pathway. SBVS of the seed molecule PTEN (PDB code: 1D5R) predicted top hits compounds that may serve as potential inhibitors of PTEN, of which the compound ZINC4235331 had the lowest binding affinity of -10 kcal/mol. The significance of screened hub genes and potential inhibitors involved in the process of LT provides novel therapeutic strategies for improving the outcomes of LT recipients during surgery. • The number of downregulated DEGs is nearly 6 times that of upregulated DEGs after LT. • DEGs are enriched in ribosome-related translation regulation. • DEGs are also enriched in infection and immune-related pathways. • PTEN-led seven hub genes and potential inhibitors are identified during LT. [ABSTRACT FROM AUTHOR]

• In this paper, we propose a new parameter identification method of inverted Preisach model, which uses the measured quasi-static concentric hysteresis loops to simulate the static DC hysteresis behavior of grain-oriented silicon steel sheets. • Then, the dynamic magnetic field intensity related to excess loss is improved by considering the nonlinear relationship between statistical parameter of excess loss V 0 and AC peaked magnetic flux density B acm , DC magnetic field intensity H dc and frequency f. • Finally, a dynamic hysteresis model in the form of field separation is proposed to predict the asymmetric hysteresis curve under AC-DC hybrid magnetization. The simulation hysteresis curve and loss under different AC-DC hybrid magnetization are compared with the measured ones, which verifies the accuracy and effectiveness of this method. Firstly, a new method for parameter identification of inverted Preisach model is proposed to simulate static DC-biasing hysteresis behavior of the grain-oriented (GO) silicon steel sheet by using the measured quasi-static concentric hysteresis loops under DC-biasing magnetization. Then, the dynamic magnetic field intensity related to excess loss is improved by considering the nonlinear relationship between the statistical parameter V 0 and the AC peaked magnetic flux density, DC magnetic field intensity as well as frequency. Finally, a dynamic hysteresis model in form of field separation is presented to predict asymmetric hysteresis curves under multi-harmonic and DC-biasing hybrid magnetization. The simulated hysteresis curves as well as losses under different AC-DC hybrid magnetizations are compared with the measured ones, which verifies the accuracy and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The polarity and viscosity of the microenvironment are associated with the control of the onset and progression of pathological diseases, including inflammation, immuno-suppression and cancer. If appropriate treatment is neglected, alcoholic acute liver injury (AALI), the initial sign of alcoholic liver diseases, may transform into hepatic lesions. Therefore, it's crucial to create a particular probe to detect AALI swiftly and track its progression. Herein a polarity and viscosity dual-responsive crimson fluorescent probe (PPBI) was designed and developed, which can target mitochondria and lipid droplets. PPBI possesses aggregation-induced emission properties, good photostability and strong anti-interference ability against pH, metal ions, anions and biomolecules. This probe can distinguish cancer cells from normal ones using changes of green and red fluorescence, as well as identify changes in the cellular microenvironment associated with inflammatory and ferroptosis processes. In addition, changes in polarity and viscosity can be amplified by in vivo imaging in a mouse model to monitor alcohol-induced acute liver injury and to effectively detect the course of pharmacological intervention therapy. All the results suggest that PPBI could be a promising real-time fluorescence imaging tool for diagnosis and treatment of acute alcoholic liver injury. [Display omitted] [ABSTRACT FROM AUTHOR]

Green and clean energy technologies, including fuel cells, metal-air batteries, water splitting et al., are becoming more significant for our lives. Oxygen reduction reaction (ORR), hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are key reaction processes for fuel cells, metal-air batteries and water splitting. Therefore, it is highly desirable to design a multifunctional catalyst, which owns catalytic performance under a widely applied range. Herein, we demonstrate a novel multifunctional catalyst (Co/Co 3 O 4 @C) by carbonizing a composite material constructed of zeolite imidazolate framework and carbon fiber paper (ZIF-L-Co@CP). It is a carbon-based material containing metallic Co and Co 3 O 4 as a low-cost and effective catalyst toward the ORR and overall water splitting. For ORR, the Co/Co 3 O 4 @C catalyst shows high half-wave potential in both alkaline and acidic media, 0.823 V for 0.1 M KOH and 0.672 V for 0.1 M HClO 4. More importantly, it exhibits good catalytic activities of hydrogen and oxygen evolutions to perform overall splitting in actual seawater. The Co/Co 3 O 4 @C catalyst was prepared by using a composite of ZIF-L-Co nanosheets grown on CP as the precursor, which not only shows excellent activity for ORR in both alkaline and acidic solutions, but also has good ability for overall actual seawater splitting. Image 1 • E 1/2 (0.823 V) of Co/Co 3 O 4 @C catalyst is close to Pt/C in 0.1 M KOH for ORR. • Co/Co 3 O 4 @C catalyst shows excellent ORR performance in 0.1 M KOH and 0.1 M HClO 4. • Co/Co 3 O 4 @C is a good catalyst for overall water splitting in actual seawater. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the extreme events of non-stationary time series in the framework of horizontal visibility graph (HVG). We give a new definition of extreme events, which incorporates the temporal structure of the series and the degree of the nodes in the HVG. An advantage of the new concept is that it does not require ad hoc treatment even when the non-stationarity arises in time series. We also use the information-theoretic methods to analyze the degree of nodes in the HVG. In the numerical analysis, we study the statistical characterizations of the extreme events of synthetic time series, including the random noises, periodic time series, random walk processes, and the long-range auto-correlated time series. Then, we study 9 time series in stock markets to identify the extreme events evolving in these non-stationary systems. Interestingly, we find that the daily closing price series perform rather close to the random walk processes, while the daily trading volume series behave quite similar to the random noises. [ABSTRACT FROM AUTHOR]

A green extractant, hydrophobic deep eutectic solvent was first introduced for extraction of tetracycline, oxytetracycline, and chlortetracycline from environmental water samples prior to high‐performance liquid chromatography determination. Deep eutectic solvents consist of methyltrioctylammonium chloride and various medium‐chain alcohols/acids, and are easy in preparation, low cost and toxicity, desirably biodegradable, and biocompatible. The overall time required for sample preparation was 6 min and the volume of organic solvent used for extraction was only 400 µL. Under the optimized extraction condition, the present method yielded low limit of detection (0.5–2.0 ng/mL), acceptable precision (relative standard deviations < 9.7%), good linearity from 2.0 to 500 ng/mL (r2 ≥ 0.9991). This optimized procedure was applied for determination of tetracyclines in different water samples with desirable spiked recovery ranged from 77.5 to 87.6%. There is, therefore, a great potential to further expand application of the method for investigation of other ultra‐trace analyte(s) in environmental matrixes. [ABSTRACT FROM AUTHOR]

Using aberration-corrected scanning transmission electron microscopy, the interface between η 1 -precipitates and Al matrix in the aged Al–2.1Zn–1.7Mg (at.%) alloy has been investigated. Atomic-resolution X-ray dispersive spectroscopy mapping reveals the occurrence of co-segregation of Mg and Zn atoms in the {002} α habit plane of the η 1 (MgZn 2) precipitates. Site-specific Mg atoms segregate outside the concave of an outermost zig-zag Zn-rich layer of the η 1 habit plane. Zn segregation surround the segregated Mg atomic columns was also observed. Hybrid molecular dynamics (MD) and Monte Carlo (MC) atomistic simulations with the accuracy of density functional theory indicate the site-specific segregation is energetically favourable. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Prisoners' affective education is a hot topic in criminal psychology. The lack of the social support for prisoners means that they are more prone to loneliness. The mental health status of the prisoners directly concerns their social adaptation when released. We therefore explored the relationship between loneliness, psychological affect, and control source in 201 prisoners. Prisoners completed the state and trait loneliness scale, the affectal scale, the internal control, powerful others, and chance scale. Mediation effect analysis was conducted to explore the mediation role of the control source from influence of loneliness on psychological affect. State loneliness indirectly affected positive affect through internal control factors. Trait loneliness directly affected negative affect, and trait loneliness indirectly affected negative affect through opportunity factors. Overall, this study uncovers some of the psychological mechanisms underlying emotional state in prisoners, highlights the need for effective psychological correction programmes in the prison system and provides reference for effectual ascension of prisoners out of jail. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is a common malignant tumor with increasing incidence and high heterogeneity among males worldwide. In the era of big data and artificial intelligence, the paradigm of biomarker discovery is shifting from traditional experimental and small data-based identification toward big data-driven and systems-level screening. Complex interactions between genetic factors and environmental effects provide opportunities for systems modeling of PCa genesis and evolution. We hereby review the current research frontiers in informatics for PCa clinical translation. First, the heterogeneity and complexity in PCa development and clinical theranostics are introduced to raise the concern for PCa systems biology studies. Then biomarkers and risk factors ranging from molecular alternations to clinical phenotype and lifestyle changes are explicated for PCa personalized management. Methodologies and applications for multi-dimensional data integration and computational modeling are discussed. The future perspectives and challenges for PCa systems medicine and holistic healthcare are finally provided. [ABSTRACT FROM AUTHOR]

On the basis of the TEAM problem 21 benchmark model, a modelling method to predict stray‐field loss under real working conditions is presented and validated to investigate the influence of harmonic excitation on stray‐field loss of shielding structural components of converter transformers in high‐voltage direct current systematically. An improved method is adapted to determine stray‐field loss of magnetic and non‐magnetic component based on the experimental measurement and numerical simulation. An experimental platform is established to measure magnetic properties and loss characteristics of the grain‐oriented silicon steel sheets, aiming at parameter identification and verification of the loss modelling applicable for laminated sheets under harmonic magnetisation. Meanwhile, the additional iron loss caused by perpendicular flux penetration is obtained by special treatment of material properties and analysed to observe its contribution to the stray‐field loss under three‐dimensional harmonic magnetisation. Field and loss comparison between measurement and simulation verifies the validation of the proposed modelling method. [ABSTRACT FROM AUTHOR]

An improved method is presented to study the efficient numerical modeling of stray-field loss in magnetic shielding excited by a 3-D harmonic magnetic field. The experimental platform is established to obtain the magnetic properties and loss model of the silicon steel lamination under harmonic magnetizations. Experimental determination is improved for more accurate stray-field loss based on the engineering-oriented model TEAM Problem 21c-M1. Prediction and evaluation of stray-field loss and additional iron loss due to harmonic excitations are achieved by special treatment of material properties in the numerical calculation of the harmonic magnetic field. [ABSTRACT FROM AUTHOR]

The aim of this work is to simulate the formation of coaxial electrohydrodynamic jet (CE-Jet) and obtain the optimized working parameters for coaxial electrohydrodynamic focused jet printing (CEFJP), then further direct writing nanoscale structures. In this paper, a pioneering simulation of CE-Jet process based on three phase flow of liquid–liquid–air model was developed. The photoresist (AZ703)/silicone oil was employed to verify the simulation. The simulated result of the CE-Jet consisted with the experimental result very well, which proves the correction of the CE-Jet model. Based on the simulation, the effect of working parameters including the applied voltage and the flow rate of inner coaxial liquid on the morphology and size of the CE-Jet were examined. With the use of the optimized working parameters obtained from the simulation and taking the materials of lead zirconate titanate (PZT) and photoresist (AZ703) as inner liquid, the stable nanoscale inner jet was focused by the compound effect of electrical shearing force, viscous shearing force and internal pressure. Then, the nanostructures of various patterns with diameter of 70 nm were directly printed. The CE-Jet model developed in this work provides a powerful tool to investigate the CEFJP process, and the CEFJP technique exhibited a promising method for producing nanoscale structures for M/NEMS devices. [ABSTRACT FROM AUTHOR]

The injection of the Direct Current (DC) bias component will lead to oversaturation of the transformer core and affect its safe operation. In this paper, the vector magnetic potential A and winding current I are used as the variables solved in the time-step finite element method to simulate the nonlinear transient magnetization characteristics of the transformer under DC bias, and the fixed-point reluctivity is introduced to deal with the nonlinear iterative problem. The field-circuit coupling relationship is established through the electromagnetic induction law, and the two-dimensional time-step finite element model of the transformer core is found. The dynamic J–A hysteresis model is used to deal with the hysteresis effect of iron cores. The fixed-point reluctivity of difference form is introduced to solve the problem of uneven transition and multi-value of magnetization curve with hysteresis in the iterative process. The determination scheme for the equivalent thickness of the core model and the initial iterative value are discussed. A laminated core transformer is made for experiments, and the accuracy and applicability of the model proposed in this paper are verified by comparing the calculation and experimental results. The influence of different voltages and different DC bias components on the electromagnetic characteristics of the transformer is analyzed. [ABSTRACT FROM AUTHOR]

Graphical abstract Design and fabrication of ultrasmall Fe 3 O 4 anchored on the GO-graphene ink-derived 3D-graphene exhibits superior excellent Li/Na-ion storage properties and supercapacitors. Abstract Transition metal oxides/carbon materials are of great interest for promising highly efficient energy storage applications owing to their low cost and eco-friendlines. Nevertheless, creating an electrode material with enhanced conductivity and electrochemical activity remains a great challenge. Here a design and fabrication of Fe 3 O 4 nanodots (∼5.2 nm) loading onto the hierarchical three dimensional graphene (Fe 3 O 4 /3D-graphene) via an interesting strategy is reported. The key factor in developing the unique 3D-graphene architecture assemblies with a graphene oxide-graphene composite ink and modifying sol-gel chemistry method is a promising strategy. The 3D-graphene with 3D omnibearing conductive and interconnecting pores can facilitate the penetration of electrolyte, accommodate the volume change and inhibit the aggregation of Fe 3 O 4 nanodots upon cycling. Benefiting from the advantages of the positive synergistic effects of Fe 3 O 4 nanodots and multilevel structures of graphene, the Fe 3 O 4 /3D-graphene electrode exhibits excellent electrochemical performances for Li/Na-ion batteries and electrochemical capacitors. As a result of the enhanced electrochemical performance, Fe 3 O 4 /3D-graphene hybrids could be regarded as a promising electrode for Li/Na-ion battery and supercapacitor. [ABSTRACT FROM AUTHOR]

The static hysteresis characteristics of soft magnetic materials were measured by the static performance testing system (SPTS). With a toroidal-shape specimen and Epstein frame, the DC magnetizations of different forms of magnetic steel sheet and grain-oriented (GO) silicon steel sheet can be realized by setting a DC excitation. Besides, the corresponding first-order reversal curves (FORCs), higher-order reversal curves (HORCs) and concentric hysteresis loop are measured. Based on the measured FORCs, the parameter identification was carried out, and the Everett function was established. Thus the inverse Preisach model was obtained. The consistency between the simulated results and the measured ones verifies the validity of the measurement method and the accuracy of the numerical simulation method of magnetic hysteresis characteristics. [ABSTRACT FROM AUTHOR]

Abstract An iron-rich pre-alloyed powder was selected out, and the pre-alloying degree of matrix materials and the sintering temperature were considered to investigate the effect of the Fe-based pre-alloyed powder on the microstructure and holding strength of impregnated diamond bit matrix. And relative density and bending strength of the specimens were measured, and then the resulting fracture surfaces were analyzed using scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results showed that the relative density, bending strength and plasticity of matrix materials are increased with the sintering temperature and the pre-alloying degree. The influence of the pre-alloying degree on them is more significant than that of the sintering temperature within the experimental parameters. Besides, Fe-based matrices have thermal corrosion effect on diamonds at high temperature sintering process. And the rate of diamond graphitization has a greatly increase with the sintering temperature changes from 900 °C to 1020 °C and the holding strength decreases. A low pre-alloying degree accelerates the rate of diamond graphitization. But an adequate pre-alloying degree of Fe-based matrix materials is conducive to improve the wettability of the matrix to diamonds, alleviate the diamond graphitization, reduce the diamonds' thermal damage and improve the holding strength. Besides, it can also greatly reduce the sintering temperature and broaden the sintering temperature range. In a word, it is feasible and reasonable that Fe-based pre-alloyed powders replace Fe elemental powders to fabricate impregnated diamond bits. And it has a good economic value and broad application prospect. Highlights • The relative density, bending strength and plasticity of the matrix were studied. • They are increased with the sintering temperature and the pre-alloying degree. • A low pre-alloying degree accelerates the rate of diamond graphitization. • A high pre-alloying degree reduces the graphitization and improves the holding force. • It can also greatly reduce the sintering temperature and broaden the sintering range. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A Si-Mo-YSZ coating was prepared on Ta-W alloy by slurry reaction sintering method. • The coated sample remained intact after oxidation at 1800 °C for 10 h. • The coating withstood 218 shock heating cycles from room temperature to 1800 °C. • The excellent performance was attributed to the dense SiO 2 -ZrO 2 -ZrSiO 4 scale. • Microstructure evolution and failure mechanism of the coating were analyzed. Abstract To develop an ultra-high temperature resistant coating for a reusable thermal protection system, a YSZ-modified Si-Mo coatings were prepared on Ta-10 W alloy by slurry reaction sintering method. The coating had a MoSi 2 -ZrSi 2 -SiO 2 outer layer and a TaSi 2 -WSi 2 inner layer. The coated sample remained intact after oxidation at 1800 °C for 10 h, while the untreated alloy was pulverized after 6 min. The coating withstood more than 200 shock heating cycles from room temperature to 1800 °C. Its outstanding oxidation resistance is attributed to its thermal matching with the alloy and formation of protective SiO 2 scale containing high-melting ZrSiO 4 and ZrO 2. [ABSTRACT FROM AUTHOR]

In this study, a novel and high-throughput liquid chromatography–tandem mass spectrometric (LC–MS-MS) assay was developed and validated for simultaneous determination of two glycopeptides (vancomycin, teicoplanin) and two small molecule compounds (meropenem, voriconazole) in human plasma. Only 50 μL of human plasma is used to quantify these four drugs simultaneously at clinical concentration levels. After a relative simple protein precipitation, the supernatant was then diluted with mobile phase acetonitrile: 0.1% formic acid (5:95, v/v) to avoid solvent effect and reduce the matrix effect. Then, the target compounds were separated on an Agilent Zorbax SB-C18 column (4.6 × 50 mm, 2.7 μm). All the target compounds were detected by positive ion mode. The teicoplanin concentration was determined as the sum of six components (A2-1, A2-2, A2-3, A2-4, A2-5 and A3-1). The method was linear in the concentration range 0.3–30 μg/mL for meropenem; 1–100 μg/mL for teicoplanin and vancomycin; 0.3–10 μg/mL for voriconazole. The lower limit of quantitation (LLOQ) of meropenem and voriconazole were 0.30 μg/mL; and the LLOQ of teicoplanin and vancomycin were 1.0 μg/mL. The intra- and inter-day accuracies were <9.67% and 13.0%, and the precisions were <14.5% at all tested concentrations. The entire analysis time for the four drugs was only 5 min for each sample. The currently developed assay was successfully applied for the therapeutic drug monitoring of 85 patients administered with standard drug treatments, demonstrating its high-throughput clinical usage for the therapeutic drug monitoring. [ABSTRACT FROM AUTHOR]

Accumulating evidence has documented that microRNAs (miRNAs) are critical regulators of neural stem cell (NSC) proliferation and differentiation. MiRNA-374b (miR-374b) has been reported to play an important role in regulating various cellular processes, such as proliferation and differentiation. However, whether miR-374b is involved in NSC proliferation and differentiation remains unclear. In this study, we investigated the potential role of miR-374b in regulating NSC proliferation and differentiation to elucidate the underlying molecular mechanism. Our results showed that miR-374b expression was significantly upregulated during NSC differentiation. Functional experiments showed that overexpression of miR-374b promoted NSC proliferation and differentiation to neurons. By contrast, miR-374b inhibition showed the opposite effect. Hairy and enhancer of split 1 (Hes1), a master regulator of neurogenesis, was predicted as a potential target gene of miR-374b by bioinformatics analysis. Dual-luciferase reporter assays showed that miR-374b could directly target the 3′-untranslated region of Hes1. Further experiments showed that miR-374b negatively regulated the mRNA and protein expression of Hes1 in NSCs. Moreover, overexpression of Hes1 significantly reversed the miR-374b overexpression-mediated effect on NSC proliferation and differentiation. In addition, knockdown of Hes1 abrogated the miR-374b inhibition-mediated effect on NSC proliferation and differentiation. Taken together, these results demonstrate that miR-374b regulates the proliferation and differentiation of NSCs through targeting Hes1 and suggest that miR-374b is a potential target for modulating NSC-mediated neurogenesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The hollow h-Ni 2 P-G/CNTs microspheres were fabricated by one-step phosphorous of Ni-MOF precursor. • The robust hollow framework with a large specific surface provides great advantages for energy storage. • The h-Ni 2 P-G/CNTs anode displays excellent electrochemical performances of LIBs/SIBs. • The excellent performances can be attributed to the synergistic effect between h-Ni 2 P, Ni, and G/CNTs. Transition metal phosphides as anode materials for energy storage batteries have attracted great attention due to their high specific capacity and safety. However, it is difficult to maintain the structural stability of the electrode material during the repeated Li+/Na+ insertion/ deintercalation process, especially at a high rate and long-life cycle. Herein, the graphene/carbon nanotubes coated Ni 2 P (h-Ni 2 P-G/CNTs) microspheres composite with hollow structure has been successfully prepared by one-step phosphorous heat treatment of Ni-MOF precursor microspheres and applied in the lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) anode. When the h-Ni 2 P-G/CNTs is used as an anode for LIBs, it delivers high reversible capacities of 506 mAh/g after 200 cycles at 0.2 A/g. As an anode for SIBs, the electrode provides 430 mAh/g capacity at 0.1 A/g after 180 cycles. The excellent performances can be attributed to the synergistically structural and electronic modulations between h-Ni 2 P, Ni, and G/CNTs, which provide more space to alleviate the volume effect on cycling and shortens the ion/charge diffusion path to speed up the reaction kinetics. [ABSTRACT FROM AUTHOR]

Abnormal SO 2 derivatives level induces mitochondrial and lysosomal dysfunction, which is associated with a variety of diseases. Therefore, it is imperative to develop fluorescent probes which are suitable for detection of SO 2 derivatives in biological systems. Herein, we developed two new ratiometric fluorescent probes, MByn and HByn, which can respond to HSO 3 − in PBS buffer solution accurately and rapidly on basis of Michael addition reaction. After addition of HSO 3 −, ratiometric response signal increases by 5 folds, accompanied by a macroscopic change of fluorescence color. What's more, the two novel fluorescent probes MByn and HByn exhibited low detection limit (LOD = 0.96/0.79 μM), good photostability and low cytotoxicity. Cell imaging experiments showed that MByn and HByn were able to localize mitochondria and lysosomes accurately and detect both exogenous and endogenous SO 2 derivatives in living cells. [Display omitted] • Beyond fluorescence ratio changed of the probes toward addition of HSO 3 − (0−20.0 μM). • The probes showed relatively high fluorescence quantum yields. • Two probes can achieve dual targeting of mitochondria and lysosomes. • The probes could be used to monitor exogenous and endogenous HSO 3 − . [ABSTRACT FROM AUTHOR]

• Childhood maltreatment is positively related to adolescent cyberbullying perpetration after controlling for relevant demographic variables. • Both individual relative deprivation and deviant peer affiliation partially mediate the relation between childhood maltreatment and cyberbullying perpetration. • Individual relative deprivation and deviant peer affiliation also mediate the relation between childhood maltreatment and cyberbullying perpetration in a sequential fashion. Guided by the general aggression model, relative deprivation theory, social control theory, and self-determination theory, the current study aims to explore the relation between childhood maltreatment and cyerbullying perpetration using a multiple mediation model, that includes individual relative deprivation and deviant peer affiliation as mediating variables. In November 2019, a sample of 1976 Chinese adolescent students attending 7th, 8th, and 10th grades (49.40% males; 8.80% only children; 32.30% middle school students; 32.10% urban students; M age = 14.43 years, SD = 1.14) responded to questionnaires regarding demographics, childhood maltreatment, individual relative deprivation, deviant peer affiliation, as well as cyberbullying perpetration. Results showed that: (a) after controlling for relevant demographic variables, childhood maltreatment was significantly and positively related to adolescent cyberbullying perpetration; (b) both individual relative deprivation and deviant peer affiliation partially mediated the relation between childhood maltreatment and cyberbullying perpetration in a parallel fashion; and (c) individual relative deprivation and deviant peer affiliation also mediated the relation between childhood maltreatment and cyberbullying perpetration in a sequential fashion. In sum, childhood maltreatment is positively related to adolescent cyberbullying perpetration, and the relation is mediated by individual relative deprivation and deviant peer affiliation both parallelly and sequentially. These findings contribute to a better understanding of how childhood maltreatment is related to adolescent cyberbullying perpetration, which has important implications for the prevention and intervention of adolescent cyberbullying perpetration. [ABSTRACT FROM AUTHOR]

The optimal design of variable section is a flow field optimization method that changes the pressure of the reacting gas in the flow channel by setting up a contraction surface in the flow channel, which is effective in improving many aspects of the proton exchange membrane fuel cell (PEMFC) performance. However, there are also problems such as uneven oxygen distribution in some of the flow channels, and the current density and net output power are not significantly improved. To find a balance among gas transfer efficiency, drainage capacity, uniformity of current density distribution, and output performance, this paper investigates the design of a variable cross-section-enhanced mass transfer flow field for PEMFC flow channel contraction by establishing a three-dimensional numerical model, starting from the sidewall width direction and the bottom height direction of the flow channel cross-section dimensions, in order to assess the effects of variable cross-section contraction at the bottom and sidewalls of the flow channel on the cell performance. The polarization curves, mass transfer capacity, current density distribution, and net output power of the variable cross-section contraction flow field are analyzed and compared with the straight flow field. On this basis, the optimum size parameters and operating parameter combinations are determined. Variable cross-sectional contraction flow field improves PEMFC output performance. The contraction of the variable cross-section contraction flow field at the sidewalls effectively improves reactive gas transfer efficiency and drainage capacity, improves current density distribution, and increases the net output power of the PEMFC. In particular, the sidewall contraction flow field has a 9.0% increase in power density, a 6.45% increase in the effective mass transfer coefficient (EMTC), a 6.52% increase in uniformity of current density distribution, and a 6.05% net power increment compared to the straight flow field, respectively. The best output performance, the highest oxygen concentration, and the lowest water concentration are achieved with a combination of parameters: number of sidewall contractions N = 6 , length L f = 6 mm , and width W f = 1.2 mm. And a wide range of air stoichiometry ratios are applied when the contraction of the variable cross-section contraction flow field is located at the sidewalls. Increasing the cathode stoichiometry ratio from 10 to 50 increased the cell power density by 25.5% and from 50 to 90 increased the cell power density by 9.5%. The simulation results can provide theoretical basis for the application of variable section flow field design for practical PEMFC. [ABSTRACT FROM AUTHOR]

In order to improve the oxidation resistance of the Ta substrate, a novel two-step process including molten salt electrodeposition (Na 2 WO 4 -WO 3 system) and halide activated pack cementation was adopted to prepare a WSi 2 –TaSi 2 coating on tantalum substrate. During the electrodeposition process, dense tungsten coatings were fabricated at current densities of 30 mA/cm2, 40 mA/cm2 and 50 mA/cm2. It was observed that the grain size exhibited a log-normal distribution. When the current density was 40 mA/cm2, the grain size and flattest surface of the tungsten coating reached 9.50 ± 0.23 μm and 6.792 μm, respectively. When performing the static oxidation test, the WSi 2 –TaSi 2 coating could effectively protect the Ta substrate oxidized at 1600 °C for 30 h. This is attributed to the presence of dense SiO 2 and Ta 2 O 5 , which acted as a protective layer and suppressed the further penetration of oxygen. Furthermore, due to the matching thermal expansion coefficient between each layer and the sealing ability of semi-molten SiO 2 , the four-layer SiO 2 –W 5 Si 3 –WSi 2 –Ta 5 Si 3 coating could successfully pass 721 thermal shock tests from 1600 °C to room temperature. [ABSTRACT FROM AUTHOR]

Rechargeable lithium-sulfur (Li-S) batteries are receiving much attention due to their high specific capacity, low cost, and environmental friendliness. Nonetheless, fast capacity decay and low specific capacity still limit their practical implementation. Herein, we report a facile strategy to overcome these challenges by the design and fabrication of 3D porous reduced graphene oxide/ultrathin MnO2 nanosheets-S aerogel (rGM-SA) composites for Li-S batteries. By a simple solvothermal reaction process, nanosized S atoms are homogeneously decorated into the 3D scaffold formed by reduced graphene oxide (rGO) and MnO2 nanosheets, which can form the homogeneous rGM-SA composites. In this porous network architecture, rGO serves as an electron and ion transfer pathway, a physical adsorption site for polysulfides, and provides structural stability. The ultrathin MnO2 nanosheets provide strong binding sites for trapping polysulfide intermediates. The 3D porous rGO/MnO2 architecture enables rapid ion transport and buffers volume expansion of sulfur during discharge. The rGM-SA composites can be directly used as lithium-sulfur battery cathodes without using binder and conductive additive. As a result of this multifunctional arrangement, the rGM-SA composites exhibit high and stable-specific capacities over 200 cycles and excellent high-rate performances. [ABSTRACT FROM AUTHOR]

The (detrended cross-correlation analysis) DCCA cross-correlation coefficient was proposed to measure the level of long-range cross-correlations between two non-stationary time series on multiple time scales. It has been applied to diverse areas of interest, although many properties of this method are not clear. In this paper, we theoretically study several fundamental properties of the DCCA cross-correlation coefficient, which contributes to acquiring more statistical characteristics of this measure. We resort to a synthetic time series that is followed by the integration and the detrending procedures of the DCCA cross-correlation coefficient, which divide the steps to estimate the coefficient into two portions. The former portion, including the integration and the detrending, is proved to be a linear transformation. The second portion is devoted to measuring Pearson's between two synthetic time series. We confirm that the DCCA cross-correlation coefficient is also a linear measure by definition. The simulations including the ARFIMA processes and the multifractal binomial measures are numerically analyzed, which confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new method to measure the influence of a third variable on the interactions of two variables. The method called transfer mutual information (TMI) is defined by the difference between the mutual information and the partial mutual information. It is established on the assumption that if the presence or the absence of one variable does make change to the interactions of another two variables, then quantifying this change is supposed to be the influence from this variable to those two variables. Moreover, a normalized TMI and other derivatives of the TMI are introduced as well. The empirical analysis including the simulations as well as real-world applications is investigated to examine this measure and to reveal more information among variables. [ABSTRACT FROM AUTHOR]

A new multifunctional probe made up of boron dipyrromethene (BODIPY) and benzimidazole neighboring phenol was designed and synthesized. This probe displays a colorimetric recognition of Hg 2+ and a ‘turn off’ fluorescent response to Cr 3+ at physiological condition. The ‘in situ’ ensemble of host and Hg 2+ shows a selective and ratiometric detection of I − via the formation of three-component ensemble. These systems were further used to detect their corresponding targets in real water sample with acceptable recovery. Compared to the comprehensive report of the single-target responsive chemosensor, these results provided an approach to design the challenging multifunctional probe. [ABSTRACT FROM AUTHOR]

A facile strategy is designed for the fabrication of flexible and free-standing ternary CoSnO 3 /graphene/carbon nanotubes (CoSnO 3 /GN/CNTs) composite papers through a simple filtration, followed by annealing process. The CoSnO 3 /GN/CNTs composite papers with high flexibility and tailorability can be easily fabricated. The CoSn(OH) 6 nanoparticles/graphene oxide/carbon nanotubes (CoSn(OH) 6 /GO/CNTs) composite papers obtained by a simple filtration method are transformed into CoSnO 3 /GN/CNTs composite papers after a thermal treatment process. In this unique composite structure, CoSnO 3 nanoparticles (nanocubes and nanoboxes) are embedded homogenously into the 3D framework of graphene and carbon nanotubes, respectively, in which offers not only a 3D conductive network and a dual restriction on the aggregation of CoSnO 3 nanoparticles, but also accommodates the large volume expansion of CoSnO 3 nanoparticles. When used directly as binder- and conductive agent-free anodes for lithium-ion batteries, the CoSnO 3 /GN/CNTs composite papers exhibit superb electrochemical properties including extraordinary reversible capacities, superior rate capabilities and stable cycle performances compared to CoSnO 3 nanoparticles and GN/CNTs paper, suggesting a new pathway for the rational engineering of anode materials. [ABSTRACT FROM AUTHOR]

• Flyover-type hollow-CoP-NCG (h -CoP-NCG) electrocatalysts were fabricated via a simple "go-between" strategy and treatment phosphating approach for Li-S battery. • Polar h -CoP nanoparticles provide adequate interfaces to chemically anchor the LiPSs and facilitate their redox reaction kinetics. • The built-in 1D CNTs (bridge) and 2D graphene (ground) form a 3D conductive network that ensures fast and continuous long-distance electron/ion transportation. • DFT calculations reveal the effective restriction effect of polysulfides via CoP with high polarity and conductivity. • The S@ h -CoP-NCG cathode enables stable and efficient sulfur electrochemistry including superior rate capability and robust cyclability. Outstanding sulfur electrochemistry in lithium-sulfur (Li-S) batteries relies heavily on the high conductivity of electrodes and the interaction of sulfur species and their reservoir matrix, which requires a reasonable design of the microstructure of each component. Herein, hollow slightly oxidized cobalt phosphides (h -O-CoP) nanoparticles are in-situ implanted into the flyover-type carbon framework composed of the N-doped C polyhedrons threaded with 1D carbon nanotubes (CNTs) on 2D graphene sheets (h -O-CoP-NCG). During the synthesis process, a facile "go-between" strategy and post-heat treatment phosphating technique of the corresponding precursors is implemented to generate abundant electrocatalytic-adsorption sites and provide better electron/ion transportation for durable Li-S batteries. Combining the merits of h -O-CoP active sites and conductive NCG channels, the h -O-CoP-NCG enables stable and efficient sulfur electrochemistry including superior rate capability of ∼857 mAh g−1 at 4 C and robust cyclability over 500 cycles at 2 C with an average decay rate of 0.033% per cycle. Even under high sulfur loading (4.2 mg cm−2), the capacity retention remains 91.6% after 300 cycles at 0.5 C. DFT calculations confirm the metallic characteristics of O-CoP (011)-Li 2 S via the orbital hybridization of the Co 3 d -S 2 p and the strong adsorption of O-CoP (011) and Li 2 S 6 , thereby enhancing the performances of the sulfur cathode. [Display omitted] [ABSTRACT FROM AUTHOR]