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In this study, plasma‐sprayed Al2O3–Cr2O3 coatings with different contents of graphene nanosheets were prepared for investigating effects of the graphene on microstructure, mechanical properties, and wear behavior of the coating. The experimental results showed that graphene increased the porosity and the microhardness of the coating. But excessive graphene decreased the microhardness remarkably. Besides, the anti‐crack initiation and propagation abilities of the coatings with graphene improved significantly. The wear rate of the coatings decreased first, and then increased with increasing the graphene content. Impressively, the wear rates of the coating with 2.9% graphene decreased by 33.5% and 36.7%, compared with those of the coating without graphene under normal loads of 5 and 15 N, respectively. The main wear mechanisms of the coatings with and without graphene are brittle fracture and abrasive wear. [ABSTRACT FROM AUTHOR]

Background: Previous studies show that oxidative stress is important in heart failure (HF) pathogenesis. The composite dietary antioxidant index (CDAI), which reflects the antioxidant profile of nutrient supplements, is associated with cardiovascular mortality risk. However, the association between CDAI and the risk of HF remains unknown. Hypothesis: In this study, we investigated the relationship between CDAI and HF risk using National Health and Nutritional Examination Survey (NHANES) data. Methods: The data of participants aged >40 years old from the NHNANES between 2001 and 2018 were obtained and used to assess the relationship between CDAI and the risk of HF. Logistic regression was used to calculate the odds ratio (OR) of CDAI for the risk of HF. Results: A total of 29 101 participants were divided into the HF (n = 1419; 4.88%) and non‐HF groups (n = 27 682; 95.12%), HF group participants had lower CDAI than the non‐HF group (−0.32 ± 0.14 vs. 0.67 ± 0.05, p <.0001). Compared with the lowest CDAI quartile (Q1), the OR for HF risk was 0.88 (0.68−1.13) for Q2 (p =.30), 0.77 (0.61−0.99) for Q3 (p =.04), and 0.68 (0.52−0.89) for Q4 (p =.01). Conclusions: CDAI was negatively associated with the risk of HF. Our findings show that the intake of an antioxidant‐rich dietary is a potential method to reduce the risk of HF. [ABSTRACT FROM AUTHOR]

Fibrosis and abnormal expression of connexin 43 (Cx43) in the ventricle play vital roles in ventricular arrhythmias (VAs) after myocardial infarction (MI). Muscone, an active monomer of heart‐protecting musk pill, has various biological activities, but its effect on susceptibility to VAs in rats with MI has not been determined. In the present study, we investigated the effects of muscone on ventricular inflammation, fibrosis, Cx43 expression, and the occurrence of VAs after MI. An MI model was established by ligating the proximal left anterior descending coronary artery. Then, the MI model rats were administered muscone (2 mg/kg/day) or vehicle (saline)via intragastric injection for 14 days. Cardiac function was evaluated by echocardiography, and an in vivo electrophysiological study was performed on Day 14. Cardiac inflammation, fibrosis, and Cx43 expression were determined by histochemical analysis and western blot analysis. Our results indicated that muscone treatment significantly improved cardiac function and inhibited ventricular inflammation, fibrosis, and nucleotide‐binding oligomerization domain, leucine‐rich repeat, and pyrin domain containing 3 (NLRP3) inflammasome activation. Electrocardiogrphy and electrophysiology studies showed that muscone shortened the QRS interval, QT interval, QTc interval, and action potential duration; prolonged the effective refractory period; and reduced susceptibility to VAs in rats after MI. Furthermore, Cx43 expression in the BZ was increased by muscone treatment, and this change was coupled by inhibition of the NLRP3/IL‐1β/p38 MAPK pathway. Taken together, our results demonstrated that muscone reduces susceptibility to VA, mainly by decreasing ventricular inflammation and fibrosis, and attenuates abnormal Cx43 expression by inhibiting NLRP3 inflammasome activation after myocardial infarction in rats. [ABSTRACT FROM AUTHOR]

SnS with high theoretical capacity is a promising anode material for lithium‐ion batteries. However, dramatic volume changes of SnS during repeated discharge/charge cycles result in fractures or even pulverization of electrode, leading to rapid capacity degradation. To solve this problem, we construct a dual‐carbon‐confined SnS nanostructure (denoted as SnS@C/rGO) by depositing semi‐graphitized carbon layers on reduced graphene oxide (rGO) supported SnS nanoplates during high‐temperature reduction. The dual carbon of rGO and in situ formed carbon coating confines growth of SnS during the high‐temperature calcination. Moreover, during the reversible Li+ storage the dual‐carbon modification enables good electronic conductivity, relieves the volume effect, and provides double insurance for the electrical contact of SnS even after repeated cycles. Benefiting from the dual‐carbon confinement, SnS@C/rGO exhibits significantly enhanced rate capability and cycling stability compared with the bare and single carbon modified SnS. SnS@C/rGO presents reversible capacity of 1029.8 mAh g−1 at 0.2 A g−1. Even at a high current density of 1 A g−1, it initially delivers reversible capacity of 934.0 mAh g−1 and retains 98.2% of the capacity (918.0 mAh g−1) after 330 cycles. This work demonstrates potential application of dual‐carbon modification in the development of electrode materials for high‐performance lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Lithium iron phosphate (LFP) cathode is renowned for high thermal stability and safety, making them a popular choice for lithium‐ion batteries. Nevertheless, on one hand, the fast charge/discharge capability is fundamentally constrained by low electrical conductivity and anisotropic nature of sluggish lithium ion (Li+) diffusion. On the other hand, the interface and internal structural degradation occurs when subjected to high‐rate condition. Herein, a multifunctional boron‐doping graphene/lithium carbonate (BG/LCO) nanointerfacial layer on surface of commercial LiFePO4 particles is designed, in which the BG layer catalyzes the rapid reaction of Li2CO3‐LiPF6 for homogeneous and mechanically robust inorganic LiF‐rich structure across the cathode‐electrolyte interphase (CEI), forms a conductive network to significantly enhance both electron and Li+ transport, and strengthens the FeO bonding to minimize both Fe loss and the formation of Fe‐Li antisite defects. Correspondingly, the modified LFP cathode achieves a high capability of 113.2 mAh g−1 at 10 C and extraordinary cyclic stability with 88.0% capacity retention over 1000 cycles as compared to the pristine LFP cathode with a capacity of only 94.0 mAh g−1 and 64.6% capacity retention. It also exhibits great enhancements of 20.1% and 3.7% at higher‐rate condition (room temperature/15 C) and the low temperature condition (−10 °C/1 C), respectively. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries have ultra–high energy density and are considered to be one of the most promising energy storage systems among all battery systems. However, due to various thorny problems, their commercial production has not yet been realized. The current experimental research normally lacks a systematic investigation into the conversion mechanism of the sulfur cathode from the electronic structure level. Actually, there is still a lack of powerful theoretical guidance for the design of high–performance Li–S batteries and the selection of modified materials still seems blind. In this article, with the chelated Fe‐polyvinyl pyrrolidone as the precursor, a series of Fe–based materials (e.g., Fe3O4@C, FeS@C, Fe3N@C) are synthesized as modified layers for battery separators, and the performance differences between them are systematically studied. It is found that the d–p band center model developed based on the d band center can reasonably combine the reaction potential of Li2S4 and performance differences. Simultaneously, the interaction between Li2S6 and the adsorption interface is simulated by ab initio molecular dynamics. This current work sheds light on promising material design for superior Li–S batteries both from a theoretical and experimental perspective. [ABSTRACT FROM AUTHOR]

A significant obstacle in the large‐scale applications of sodium borohydride (NaBH4) for hydrogen storage is its high cost. Herein, we report a new method to synthesize NaBH4 by ball milling hydrated sodium tetraborate (Na2B4O7 ⋅ 10H2O) with low‐cost Al or Al88Si12, instead of Na, Mg or Ca. An effective strategy is developed to facilitate mass transfer during the reaction by introducing NaH to enable the formation of NaAlO2 instead of dense Al2O3 on Al surface, and by using Si as a milling additive to prevent agglomeration and also break up passivation layers. Another advantage of this process is that hydrogen in Na2B4O7 ⋅ 10H2O serves as a hydrogen source for NaBH4 generation. Considering the low cost of the starting materials and simplicity in operation, our studies demonstrate the potential of producing NaBH4 in a more economical way than the commercial process. [ABSTRACT FROM AUTHOR]

To develop anode materials with superior volumetric storage is crucial for practical application of lithium/sodium‐ion batteries. Here, we have developed a micro/nanostructured SnS/few‐layer graphene (SnS/FLG) composite by facile scalable plasma milling. Inside the hybrid, SnS nanoparticles are tightly supported by FLG, forming nanosized primary particles as building blocks and assembling to microsized secondary granules. With this unique micro/nanostructure, the SnS/FLG composite possesses a high tap density of 1.98 g cm−3 and thus ensures a high volumetric storage. The combination of SnS nanoparticles and FLG nanosheets can not only enhance the overall electrical conductivity and facilitate the ion diffusion greatly, but alleviate the large volume expansion of SnS effectively and maintain the electrode integrity during cycling. Thus, the densely compacted SnS/FLG composite exhibits superior volumetric lithium and sodium storage, including high volumetric capacities of 1926.5/1051.4 mAh cm−3 at 0.2 A g−1, and high retained capacities of 1754.3/760.3 mAh cm−3 after 500 cycles at 1.0 A g−1. With superior volumetric storage performance and facile scalable synthesis, the SnS/FLG composite can be a promising anode for practical batteries application. [ABSTRACT FROM AUTHOR]

Sodium borohydride (NaBH4) is among the most studied hydrogen storage materials because it is able to deliver high‐purity H2 at room temperature with controllable kinetics via hydrolysis; however, its regeneration from the hydrolytic product has been challenging. Now, a facile method is reported to regenerate NaBH4 with high yield and low costs. The hydrolytic product NaBO2 in aqueous solution reacts with CO2, forming Na2B4O7⋅10 H2O and Na2CO3, both of which are ball‐milled with Mg under ambient conditions to form NaBH4 in high yield (close to 80 %). Compared with previous studies, this approach avoids expensive reducing agents such as MgH2, bypasses the energy‐intensive dehydration procedure to remove water from Na2B4O7⋅10 H2O, and does not require high‐pressure H2 gas, therefore leading to much reduced costs. This method is expected to effectively close the loop of NaBH4 regeneration and hydrolysis, enabling a wide deployment of NaBH4 for hydrogen storage. [ABSTRACT FROM AUTHOR]

Amorphous nanoparticles of ZnO and TiO2 embedded in carbon nanocages (AZT⊂CNCs) were successfully synthesized through a simple annealing process of TiO2‐coated zeolitic imidazolate framework‐8 (ZIF‐8). In the current anode of AZT⊂CNCs, tiny ZnO and TiO2 nanoparticles were uniformly distributed in the carbon matrix (carbon nanocages), which could effectively buffer the volume expansion of electroactive ZnO and provide excellent electric conductivity. After fully investigating the electrochemical performance of the AZT⊂CNCs samples obtained with different additive amounts of tetrabutyl orthotitanate (TBOT) for TiO2 coating, it has been found that AZT‐30 (0.1 g ZIF‐8 with 30 mL TBOT) shows the best cycle stability (510 mA h g−1 after 350 cycles at 200 mA g−1) and a superior rate capability (610 mA h g−1 after 3500 cycles at 2 A g−1). The greatly enhanced Li‐ion storage performance could be ascribed to the fact that the introduction of amorphous TiO2 could activate the reversible lithiation/delithiation reaction of ZnO during the charge/discharge process. Dramatically enhanced: Amorphous nanoparticles of ZnO and TiO2 embedded in carbon nanocages (AZT⊂CNCs) were successfully synthesized by a simple annealing process of TiO2‐coated ZIF‐8 (see figure). As a Li‐ion battery anode, the hollow structure and porous carbon matrix make these materials useful. Moreover, with the addition of TiO2, the electrochemical reactions of the ZnO anode are greatly activated. [ABSTRACT FROM AUTHOR]

Abstract: On account of increasing demand for energy storage devices, sodium‐ion batteries (SIBs) with abundant reserve, low cost, and similar electrochemical properties have the potential to partly replace the commercial lithium‐ion batteries. In this study, a facile metal‐organic framework (MOF)‐derived selenidation strategy to synthesize in situ carbon‐encapsulated selenides as superior anode for SIBs is rationally designed. These selenides with particular micro‐ and nanostructured features deliver ultrastable cycling performance at high charge–discharge rate and demonstrate ultraexcellent rate capability. For example, the uniform peapod‐like Fe7Se8@C nanorods represent a high specific capacity of 218 mAh g−1 after 500 cycles at 3 A g−1 and the porous NiSe@C spheres display a high specific capacity of 160 mAh g−1 after 2000 cycles at 3 A g−1. The current simple MOF‐derived method could be a promising strategy for boosting the development of new functional inorganic materials for energy storage, catalysis, and sensors. [ABSTRACT FROM AUTHOR]

Abstract: The sulfur cathode, as a new generation of lithium‐ion battery cathode material, has a high theoretical energy density of about 2500 Wh kg−1. However, the low conductivity of sulfur and the “shuttle effect”, widely presenting in the lithiation/de‐lithiation process, seriously hinder its practical application. Here, we report a new nanoconfined oxidation route (first complete oxidation of metal sulfide and subsequently partial oxidation of the generated S from sulfide) for S cathode encapsulated with MnO2 nanosheets and N‐doped carbon hollow spheres. This nanoconfined oxidation route can successfully confine the sulfur particles in the interior of the carbon shell, and the rationally introduced nonpolar carbon and polar MnO2 can both reduce the dissolution of polysulfide during the charge‐discharge process. The obtained well‐defined S‐MnO2@C cathode exhibits high specific capacity with excellent cycling performance and superior rate capability. [ABSTRACT FROM AUTHOR]

Sodium borohydride (NaBH4) is regarded as an excellent hydrogen-generated material, but its irreversibility of hydrolysis and high cost of regeneration restrict its large-scale application. In this study a convenient and economical method for NaBH4 regeneration is developed for the first time without hydrides used as starting materials for the reduction process. The real hydrolysis by-products (NaBO2 ·2H2O and NaBO2 ·4H2O), instead of dehydrated sodium metaborate (NaBO2), are applied for the regeneration of NaBH4 with Mg at room temperature and atmospheric pressure. Therefore, the troublesome heat-wasting process to obtain NaBO2 using a drying procedure at over 350 °C from NaBO2 · xH2O is omitted. Moreover, the highest regeneration yields of NaBH4 are achieved to date with 68.55% and 64.06% from reaction with NaBO2 ·2H2O and NaBO2 ·4H2O, respectively. The cost of NaBH4 regeneration shows a 34-fold reduction compared to the previous study that uses MgH2 as the reduction agent, where H2 is obtained from a separate process. Furthermore, the regeneration mechanism of NaBH4 is clarified and the intermediate compound, NaBH3(OH), is successfully observed for the first time during the regeneration process. [ABSTRACT FROM AUTHOR]

The electrode-electrolyte interface plays a key role in the energy density and safety of the Li-ion battery. The interfaces evolution induces the capacity increasing in many metal oxide anodes and attracts much attention. Here, the origin of the capacity increasing is verified by our long-life Sn-Fe3O4@ graphite composite anode. By analyzing the electrochemical curves, the Coulombic efficiency and interface/surface chemistry, the capacity increasing comes from the formation and dissolution of growing solid electrolyte interphase (SEI). The dissolution process only happens in certain high potential and under the effect of the sufficient nanosized metal particles with high electrocatalysis. The formation/dissolution of SEI is partial reversible to promote the conversion of the components in SEI. This conversion causes the Li+ irreversible consuming, but also favors the kinetics of the composite anode in the battery system. [ABSTRACT FROM AUTHOR]

To alleviate the capacity degradation of anode materials for Li-ion batteries, caused by serious volume expansion and particle aggregation, intensive attention has been devoted to the rational design and fabrication of novel anode architectures. Herein, self-supported CoP nanorod arrays have been facilely synthesized using hydrothemally deposited Co(CO3)0.5(OH) ⋅0.11 H2O nanorod arrays as the precursor, through a gas-phase phosphidation method. As the anode for Li-ion batteries, such 3D interconnected CoP nanorod arrays show an initial discharge capacity of 1067 mAh g−1 and a high reversible charge capacity of 737 mAh g−1 at 0.4 Ag−1. After 400 cycles, their specific capacity can reach 510 mAh g−1; even after 900 cycles, they can still deliver a specific capacity of 390 mAh g−1. CoP//LiCoO2 full-cells also exhibit a high reversible capacity of 400 mAh g−1 after 50 cycles. These unique 3D interconnected CoP nanorod arrays also show ultrastable cycling performance over 500 cycles when used as the anode in a Na-ion battery. [ABSTRACT FROM AUTHOR]

Mny commercial software packages for X-ray diffraction pattern analysis are capable of identifying multiple phases in bulk materials. However, X-ray diffraction patterns cannot record those phases with very small volume ratio or non-homogeneous distribution, which may mean that researchers have to use instead electron diffraction patterns from a very small region of interest. EDP2XRD, a new program for converting electron diffraction patterns into X-ray diffraction patterns, is described here. The program has been developed in order to utilize X-ray analysis software for electron diffraction patterns taken from mixed-phase nanocrystalline materials with a transmission electron microscope. It is specifically designed for material researchers who are engaged in crystallographic microstructure analysis. The difference from other popular commercial software for crystallography is that this program provides new options to convert and plot X-ray diffraction patterns for arbitrary electron diffraction rings and to process raw images to enhance conversion performance. The program contains the necessary crystallographic calculator to list planar d spacings and corresponding X-ray diffraction angles. [ABSTRACT FROM AUTHOR]

Anatase TiO2 nanocrystals were painted on H-titanate nanofibers by using an aqueous solution of titanyl sulfate. The anatase nanocrystals were bonded solidly onto the titanate fibers through formation of coherent interfaces at which the oxygen atoms were shared by the nanocrystals and the fiber. This approach allowed us to create large anatase surfaces on the nanofibers, which are active in photocatalytic reactions. This method was also applied successfully to coat anatase nanocrystals on surfaces of fly ash and layered clay. The painted nanofibers exhibited a much higher catalytic activity for the photocatalytic degradation of sulforhodamine B and the selective oxidation of benzylamine to the corresponding imine (with a product selectivity >99 %) under UV irradiation than both the parent H-titanate nanofibers and a commercial TiO2 powder, P25. We found that gold nanoparticles supported on H-titanate nanofibers showed no catalytic activity for the reduction of nitrobenzene to azoxybenzene, whereas the gold nanoparticles supported on the painted nanofibers and P25 could efficiently reduce nitrobenzene to azoxybenzene as the sole product under visible light irradiation. These results were different from those from the reduction on the gold nanoparticles photocatalyst on ZrO2, in which the azoxybenzene was the intermediate and converted to azobenzene quickly. Evidently, the support materials significantly affect the product selectivity of the nitrobenzene reduction. Finally, the new photocatalysts could be easily dispersed into and separated from a liquid because of their fibril morphology, which is an important advantage for practical applications. [ABSTRACT FROM AUTHOR]

The six orientation relationships (ORs) found in the Mg/γ-Mg17Al12 precipitation system were summarized and systematically interpreted based on the atomic structure of the precipitate γ-Mg12Al17 and the invariant deformation element (IDE) model for diffusional phase transformations. It was found that the pseudo-twinning relationship between the six ORs is a reflection of the pseudo-twinning relationship between the close- or near-close-packing planes (), (11), (033), (411) and () in the precipitate γ-Mg12Al17. As a result, the Pitsch-Schrader OR is the starting point for the other five ORs. Multiple morphologies, growth directions and habit planes could be rationally interpreted by the IDE model. This implies that a multiple orientation relationship between the variants of precipitates is favourable in order to minimize the gross energy of precipitation systems in which the matrix has a simple structure while the precipitate has a complicated structure, such as Mg/γ-Mg12Al17, Mg/δ-Zn2Zr3 and Mg/η-MgZn2 couples. [ABSTRACT FROM AUTHOR]

Stereographic projection is one of the most powerful research tools for crystallography in materials science. A new program for full operation of stereographic projections and in-depth exploration of crystallographic orientation relationships is described. It is specifically designed for materials researchers who are in need of tools for extensive crystallographic analysis. The difference from other popular commercial software for crystallography is that this program provides new options for users to plot and fully control stereographic projections of an arbitrary pole centre for an arbitrary crystal structure and to illustrate composite stereographic projections, which are necessary to explore the orientation relationships between two phases. The program is able to perform a range of essential crystallographic calculations. [ABSTRACT FROM AUTHOR]

Polycrystalline Ho2W3O12 is prepared by calcination of stoichiometric amounts of Ho2O3 and WO3 in air (1100 °C, 10 h) with different cooling treatments (850 °C plus furnace cooling or 1100 °C plus quenching in H2O) to probe the relationship between phase formation and preparative conditions. [ABSTRACT FROM AUTHOR]