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The evolution of microstructure has a significant impact on the coordinated deformation of bimetallic materials at high temperatures. This study conducted hot compression experiments on the 40Cr/Q345B bimetallic ring blanks. Based on EBSD measurement data, the parent austenite was reconstructed, and the dynamic recrystallization (DRX) fraction was evaluated using a grain orientation spread method. The DRX evolution of bimetallic ring blanks during hot deformation was studied, and the effects of different deformation conditions on the microstructure, microhardness, and interface element diffusion were analyzed. The coordinated deformation mechanism of the bimetallic ring blank at high temperatures was investigated. The results indicate that the 40Cr/Q345B bimetallic ring blank produced by centrifugal casting formed a 4.2 mm thick bonding layer (BL), with a smooth transition of elements, microstructure distribution, and grain size. The DRX evolution of 40Cr, BL, and Q345B was not synchronized, and the DRX of 40Cr occurred earlier with stable deformation. Q345B had a lower degree of DRX and a tendency of localized flow. The evolution of the BL approached 40Cr. When the strain reached 0.69, the DRX volume fractions of 40Cr, BL, and Q345B were 88.25%, 81.9%, and 53.77%, respectively. At higher temperatures and lower strain rates, the average grain sizes of 40Cr, BL, and Q345B were 150.6, 139.33, and 128.84 μm with severe grain coarsening. Coordinated deformation was enhanced by increasing the temperature and strain rate. Higher temperatures or lower strain rates increased the thickness of the metallurgical BL by promoting element diffusion. The synergistic strengthening effect of heterogeneous deformation induced strengthening and work hardening, combined with the DRX evolution gradient at the BL, played a coordinating role in the microstructure evolution of the bimetallic ring blank. [ABSTRACT FROM AUTHOR]

The effect of barium ions on the biomineralization of calcium and magnesium ions is often overlooked when utilizing microbial-induced carbonate precipitation technology for removing barium, calcium, and magnesium ions from oilfield wastewater. In this study, Bacillus licheniformis was used to bio-precipitate calcium, magnesium, and barium ions. The effects of barium ions on the physiological and biochemical characteristics of bacteria, as well as the components of extracellular polymers and mineral characteristics, were also studied in systems containing coexisting barium, calcium, and magnesium ions. The results show that the increasing concentrations of barium ions decreased pH, carbonic anhydrase activity, and concentrations of bicarbonate and carbonate ions, while it increased the contents of humic acids, proteins, polysaccharides, and DNA in extracellular polymers in the systems containing all three types of ions. With increasing concentrations of barium ions, the content of magnesium within magnesium-rich calcite and the size of minerals precipitated decreased, while the full width at half maximum of magnesium-rich calcite, the content of O-C=O and N–C=O, and the diversity of protein secondary structures in the minerals increased in systems containing all three coexisting ions. Barium ions does inhibit the precipitation of calcium and magnesium ions, but the immobilized bacteria can mitigate the inhibitory effect. The precipitation ratios of calcium, magnesium, and barium ions reached 81–94%, 68–82%, and 90–97%. This research provides insights into the formation of barium-enriched carbonate minerals and offers improvements for treating oilfield wastewater. [ABSTRACT FROM AUTHOR]

For the pursuit of high energy supercapacitors, the development of high performance pseudocapacitance or battery-type negative electrode material is urgently needed to make up for the capacity shortage of commercial electric double layer capacitor (EDLC) type materials. Herein, a porous and defect-rich FexBi2−xS3 solid solution structure is firstly constructed by employing Fe-doped Bi2O2CO3 porous nanosheets as a precursor, which presents dramatically increased energy storage performance than Bi2S3 and FeS2 phase. For the optimized FexBi2−xS3 solid solution (FeBiS-60%), the Fe solute is free and random dispersed in Bi2S3 framework, which can effectively modulate the electronic structure of Bi element and introduce rich-defect due to the existence of Fe(II). Meanwhile, the FeBiS-60%, constructed by pore nanosheets that are assembled by self-supported basic nanorod units, presents rich mesoporous channels for fast mass transfer and abundant active sites for promoting capacity performance. Therefore, a high capacitance of 832.8 F·g−1 at a current density of 1 A·g−1 is achieved by the FeBiS-60% electrode. Furthermore, a fabricated Ni3S2@Co3S4 (NCS)//FeBiS-60% hybrid supercapacitor device delivers an outstanding energy density of 85.33 Wh·kg−1 at the power density of 0.799 kW·kg−1, and ultra-long lifespan of remaining 86.7% initial capacitance after 8700 cycles. [ABSTRACT FROM AUTHOR]

A ternary hierarchical hybrid Ni@CoxSy/poly(3,4-ethylenedioxythiophene)-reduced graphene oxide (Ni@CoxSy/PEDOT-rGO) is rationally designed and in situ facilely synthesized as electrocatalyst to construct a binder-free sensing platform for non-enzymatic glucose monitoring through traditional electrodeposition procedure. The as-prepared Ni@CoxSy/PEDOT-rGO presents unique hierarchical structure and multiple valence states as well as strong and robust adhesion between Ni@CoxSy/PEDOT-rGO and GCE. Profiting from the aforementioned merits, the sensing platform constructed under optimal conditions achieved a wide detection range (0.2 μM ~ 2.0 mM) with high sensitivity (1546.32 μA cm–2 mM–1), a rapid response time (5 s), an ultralow detection limit (0.094 μM), superior anti-interference performance, excellent reproducibility and considerable stability. Furthermore, the sensor demonstrates an acceptable accuracy and appreciable recoveries ranging from 90.0 to 102.0% with less than 3.98% RSD in human blood serum samples, indicating the prospect of the sensor for the real samples analysis. It will provide a strategy to rationally design and fabricate ternary hierarchical hybrid as nanozyme for glucose assay. [ABSTRACT FROM AUTHOR]

This study investigated the effect of rapamycin alone and in combination with chemotherapy (doxorubicin and cytarabine) on AML. Human acute monocytic leukemia cell line SHI-1 and NPG AML model mice created by intravenous injection of SHI-1 cell were treated with rapamycin, chemotherapy, or rapamycin plus chemotherapy. Analysis by cell counting kit-8, western blot, flow cytometry, and immunohistochemistry was performed, and results suggested that both rapamycin and chemotherapy inhibited proliferation of SHI-1 cells both in vitro and in vivo, suppressed neoplasm growth in vivo, and promoted survival of NPG AML mice. The antitumor effect of rapamycin plus chemotherapy was better than that of rapamycin alone and chemotherapy alone. In addition, western blot results demonstrated that rapamycin inhibited the phosphorylation of mTOR downstream targets 4EBP1 and S6K1 in SHI-1 cells, and increased the pro-apoptosis-related protein Bax and autophagy-associated proteins Beclin-1, LC3B-II, and ATG5 while reducing the anti-apoptosis-related protein Bcl-2. In conclusion, the results of this study indicate that rapamycin acts synergistically with doxorubicin and cytarabine in AML treatment, and its underlying mechanism might be associated with mTORC1 pathway-mediated apoptosis and autophagy. [ABSTRACT FROM AUTHOR]

In this paper, the horizontal centrifugal casting process of 40Cr/Q345B bimetallic ring blank was simulated by FLOW-3D. The effects of pouring temperature and axial temperature difference on the quality and consistency of interfacial bonding were studied. The bonding quality and overall performance of the bimetallic ring blanks were investigated by diffusion behavior, microstructure and mechanical properties. The results showed that when the initial outer temperature or the inner pouring temperature was too high, mix flow easily occurred at the interface; when the initial outer temperature or the inner pouring temperature was too low, the interface was poorly bonded. The consistency of interfacial bonding was affected by the axial temperature difference. When the initial outer temperature was 1350 °C, and the inner pouring temperature was 1580 °C, the interface was well bonded. Gradient transitions were formed in the elemental distribution and microstructure of the bonding layer. No obvious defects were found in the bonding area. The mechanical properties of the bimetal were close to those of Q345B, which were between those of 40Cr and Q345B. According to the simulation results and experimental results, it was concluded that the bonding mechanism of the 40Cr/Q345B bimetallic interface was first fusion and then diffusion. [ABSTRACT FROM AUTHOR]

Solar-light-driven CO2 reduction CO to CH4 and C2H6 is a complex process involving multiple elementary reactions and energy barriers. Therefore, achieving high CH4 activity and selectivity remains a significant challenge. Here, we integrate bifunctional Cu2O and Cu-MOF (MOF = metal-organic framework) core–shell co-catalysts (Cu2O@Cu-MOF) with semiconductor TiO2. Experiments and theoretical calculations demonstrate that Cu2O (Cu+ facilitates charge separation) and Cu-MOF (Cu2+ improves the CO2 adsorption and activation) in the core–shell structure have a synergistic effect on photocatalytic CO2 reduction, reducing the formation barrier of the key intermediate ⋆COOH and ⋆CHO. The photocatalyst exhibits high CH4 yield (366.0 µmol·g−1·h−1), efficient electron transfer (3283 µmol·g−1·h−1) and hydrocarbon selectivity (95.5%), which represents the highest activity of Cu-MOF-based catalysts in photocatalytic CO2 reduction reaction. This work provides a strategy for designing efficient photocatalysts from the perspective of precise regulation of components. [ABSTRACT FROM AUTHOR]

Highlights: The flower-like δ-MnO2 nanostructures with controlled oxygen vacancies as an extraordinary ZIBs cathode are innovatively developed. The cathode can present large capacity and high-rate zinc-ion storage. DFT analysis substantially unveils the effects of various vacancy concentrations on their electrochemical performances. In recent years, manganese-based oxides as an advanced class of cathode materials for zinc-ion batteries (ZIBs) have attracted a great deal of attentions from numerous researchers. However, their slow reaction kinetics, limited active sites and poor electrical conductivity inevitably give rise to the severe performance degradation. To solve these problems, herein, we introduce abundant oxygen vacancies into the flower-like δ-MnO2 nanostructure and effectively modulate the vacancy defects to reach the optimal level (δ-MnO2−x−2.0). The smart design intrinsically tunes the electronic structure, guarantees ion chemisorption–desorption equilibrium and increases the electroactive sites, which not only effectively accelerates charge transfer rate during reaction processes, but also endows more redox reactions, as verified by first-principle calculations. These merits can help the fabricated δ-MnO2−x−2.0 cathode to present a large specific capacity of 551.8 mAh g−1 at 0.5 A g−1, high-rate capability of 262.2 mAh g−1 at 10 A g−1 and an excellent cycle lifespan (83% of capacity retention after 1500 cycles), which is far superior to those of the other metal compound cathodes. In addition, the charge/discharge mechanism of the δ-MnO2−x−2.0 cathode has also been elaborated through ex situ techniques. This work opens up a new pathway for constructing the next-generation high-performance ZIBs cathode materials. [ABSTRACT FROM AUTHOR]

Carbon-based electromagnetic wave absorbing materials (absorbers) adhered with metallic sulfide nanoparticles of good electrical conductivity attract increasing researchers' attention. In this study, on the basis of carbon fiber (Cf)@Fe3O4 nanocomposites obtained by the electrostatic spinning and reflow method, Cf@FeS2 nanocomposite was successfully prepared during a further hydrothermal process. The products exhibit excellent electromagnetic wave absorption performances with a minimum reflection loss (RLmin) of −54.11 dB at 2.13 mm matching thickness. At the same time, the optimal effective absorption bandwidth (EAB) value of 6.04 GHz at a thickness of 1.98 mm covers the whole Ku band, suggesting its excellent electromagnetic wave absorption performances. In addition, the interlaced network structure constructed by carbon fiber, outstanding conductivity of FeS2 nanoparticles, and interfacial polarization from hetero-structure play significant parts in enhancing the electromagnetic parameters and absorption performances. All these results suggest that the Cf@FeS2 nanocomposites can be taken as a new electromagnetic wave-absorbing material under their low density, simple craft, and strong absorption characteristics. [ABSTRACT FROM AUTHOR]

Semiconductors-based heterogeneous photocatalytic water splitting has been extensively studied, but it still remains challenging to accelerate the separation of electron—hole pairs and facilitate the reaction kinetics. Here we report a general strategy to fabricate highly efficient Pt/TiO2 photocatalyst by coupling the Pt co-catalysts and surface oxygen vacancies (VO) of TiO2. TiO2 was pre-modified with alkali or alkaline earth metals ion solutions, which produce a large number of surface hydroxyl on TiO2. Subsequently, the photodeposited Pt sub-nanoparticles substitute surface hydroxyl and induce surface VO on TiO2. The coupling of Pt and surface VO on TiO2 can accelerate the extraction of photo-charges through the interaction of Pt—VO—Ti bonds and reduce the hydrogen evolution barrier, thereby promoting the photocatalytic activity. The synthesized Pt-VO-TiO2 sample exhibits a photocatalytic hydrogen evolution activity as high as 1.5 L·g−1·h−1, which is 2.2 times that of traditional Pt/TiO2. Our findings in-depth understand the synergistic effect of co-catalysts and defects on photocatalysis and open up new possibilities for achieving robust photocatalytic water splitting. [ABSTRACT FROM AUTHOR]

Correlating atomic configurations—specifically, degree of disorder (DOD)—of an amorphous solid with properties is a long-standing riddle in materials science and condensed matter physics, owing to difficulties in determining precise atomic positions in 3D structures1–5. To this end, 2D systems provide insight to the puzzle by allowing straightforward imaging of all atoms6,7. Direct imaging of amorphous monolayer carbon (AMC) grown by laser-assisted depositions has resolved atomic configurations, supporting the modern crystallite view of vitreous solids over random network theory8. Nevertheless, a causal link between atomic-scale structures and macroscopic properties remains elusive. Here we report facile tuning of DOD and electrical conductivity in AMC films by varying growth temperatures. Specifically, the pyrolysis threshold temperature is the key to growing variable-range-hopping conductive AMC with medium-range order (MRO), whereas increasing the temperature by 25 °C results in AMC losing MRO and becoming electrically insulating, with an increase in sheet resistance of 109 times. Beyond visualizing highly distorted nanocrystallites embedded in a continuous random network, atomic-resolution electron microscopy shows the absence/presence of MRO and temperature-dependent densities of nanocrystallites, two order parameters proposed to fully describe DOD. Numerical calculations establish the conductivity diagram as a function of these two parameters, directly linking microstructures to electrical properties. Our work represents an important step towards understanding the structure–property relationship of amorphous materials at the fundamental level and paves the way to electronic devices using 2D amorphous materials.Varying growth temperatures enables the tuning of the degree of disorder, which is fully described by the absence/presence of medium-range order and temperature-dependent densities of nanocrystallites, and electrical conductivity in amorphous monolayer carbon films. [ABSTRACT FROM AUTHOR]

In the last decade, electromagnetic pollution has caused people's considerable attention. Developing absorbing material with low cost, lightweight, simple preparation, and high electromagnetic attenuation efficiency has become a feasible means to deal with this problem. In this work, core-shell SiCNWs@MnO2@PPy (NWs: nanowires, PPy: polypyrrole) heterostructures composed of SiC nanowires core, MnO2 nanosheets inter-layer, and PPy coating were successfully prepared through chemical vapor deposition and two-step electrodeposition process. Taking advantage of the interfacial polarization and dipole polarization, the obtained product displays excellent electromagnetic wave absorption performances with the minimum reflection loss (RLmin) of −50.59 dB when the matching thickness is 2.41 mm, and the optimal effective absorption bandwidth (EAB) value reaches to 6.64 GHz at a matching thickness of 2.46 mm, revealing that the SiCNWs@MnO2@PPy nanocomposite could be served as a promising electromagnetic wave absorbing material. On the basis of systematic analysis concerning the electromagnetic parameters, the dissipation process of the incident electromagnetic wave was demonstrated reasonably, which may provide a referable preparation strategy for novel heterostructures, especially nonmagnetic lightweight absorbing material. [ABSTRACT FROM AUTHOR]

Electrocatalytic water electrolysis, involving hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), two half-reactions, is an eco-friendly approach toward hydrogen production. In this work, needle-like Ru-Fe-Ni-P on NiFe foam is prepared through corrosive engineering and following a low-temperature phosphorization procedure for overall water-splitting. The as-designed Ru-Fe-Ni-P exhibits a porous needle-like structure, surface, and binder-free merits, and then can expose rich active sites, favor the transportation of mass/electron, and accelerate the reaction kinetics during catalytic process. Then, the synthesized Ru-Fe-Ni-P owns remarkable catalytic performance for HER, with 18 and 67 mV to reach 10 mA·cm−2 in alkaline and neutral media. Moreover, a low cell voltage of 1.51 V is required to produce a current of 10 mA·cm−2 in a two electrode electrolyzer with excellent stability. Interestingly, sustainable energies can power the electrolyzer effectively with abundant hydrogen generation. [ABSTRACT FROM AUTHOR]

Development of a general regulatory strategy for efficient overall water splitting remains a challenging task. Herein, a simple, cost-fairness, and general fluorination strategy is developed to realize surface reconstruction, heteroatom doping, and vacancies engineering over cobalt phosphide (CoP) for acquiring high-performance bifunctional electrocatalysts. Specifically, the surface of CoP nanoarrays (NAs) becomes rougher, meanwhile F doped into CoP lattice and creating amounts of P vacancies by fluorination, which caused the increase of active sites and regulation of charge distribution, resulting the excellent electrocatalyst performance of F-CoP NAs/copper foam (CF). The optimized F-CoP NAs/CF delivers a lower overpotential of only 35 mV at 10 mA·cm−2 for hydrogen evolution reaction (HER) and 231 mV at 50 mA·cm−2 for oxygen evolution reaction (OER), and the corresponding overall water splitting requires only 1.48 V cell voltage at 10 mA·cm−2, which are superior to the most state-of-the-art reported electrocatalysts. This work provides an innovative and feasible strategy to construct efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Background: Hsa_circ_0080425 (circ_0080425) is newly identified to correlate with the progression of diabetic nephropathy (DN). However, its role and mechanism in DN process is not very clear. Methods: Cell counting kit-8 assay, flow cytometry, scratch wound assay, and western blotting were performed to measure endothelial cell dysfunction. Expression of circ_0080425, microRNA (miR)-140-3p and fibronectin 1 (FN1) were determined by quantitative real-time PCR and western blotting. The direct interaction was confirmed by dual-luciferase reporter assay. Results: High-glucose (HG) treatment could induce inhibition of cell proliferation, cell cycle entrance and wound healing rate in human umbilical vein endothelial cells (HRGEC), and enhancement of apoptosis rate. Circ_0080425 expression was upregulated by HG, and exhausting circ_0080425 could attenuate HG-induced above effects in HRGEC. MiR-140-3p was sponged by circ_0080425, and its inhibitor reversed the regulation of circ_0080425 knockdown on HG-induced HRGEC injury. FN1 was targeted by miR-140-3p, and its overexpression also restored the inhibitory effect of miR-140-3p on HC-induced HRGEC injury. Conclusion: Circ_0080425 expression might contribute to HG-induced endothelial cell injury, and circ_0080425/miR-140-3p/FN1 axis was a potential therapeutic approach to interfere DN process. Highlights: Knockdown of circ_0080425 mitigates HG-induced HRGEC injury. Circ_0080425 sponges miR-140-3p. MiR-140-3p targets FN1. [ABSTRACT FROM AUTHOR]

Highlights: Three-dimensional ordered porous carbon foam with abundant hetero-atoms is successfully prepared through employing silica microspheres template. The pore volume and specific surface area are effectively adjusted by an equivalent substitute strategy to investigate their influence on electromagnetic wave absorption performances. The attenuation mechanism of electromagnetic wave is clarified according to the contribution of conduction loss and polarization loss on dielectric loss.Three-dimensional (3D) ordered porous carbon is generally believed to be a promising electromagnetic wave (EMW) absorbing material. However, most research works targeted performance improvement of 3D ordered porous carbon, and the specific attenuation mechanism is still ambiguous. Therefore, in this work, a novel ultra-light egg-derived porous carbon foam (EDCF) structure has been successfully constructed by a simple carbonization combined with the silica microsphere template-etching process. Based on an equivalent substitute strategy, the influence of pore volume and specific surface area on the electromagnetic parameters and EMW absorption properties of the EDCF products was confirmed respectively by adjusting the addition content and diameter of silica microspheres. As a primary attenuation mode, the dielectric loss originates from the comprehensive effect of conduction loss and polarization loss in S-band and C band, and the value is dominated by polarization loss in X band and Ku band, which is obviously greater than that of conduction loss. Furthermore, in all samples, the largest effective absorption bandwidth of EDCF-3 is 7.12 GHz under the thickness of 2.13 mm with the filling content of approximately 5 wt%, covering the whole Ku band. Meanwhile, the EDCF-7 sample with optimized pore volume and specific surface area achieves minimum reflection loss (RLmin) of − 58.08 dB at 16.86 GHz while the thickness is 1.27 mm. The outstanding research results not only provide a novel insight into enhancement of EMW absorption properties but also clarify the dominant dissipation mechanism for the porous carbon-based absorber from the perspective of objective experiments. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNA ANRIL has been found to be involved in the pathogenesis of diabetic kidney disease (DKD) and is expected to be a new target for prevention of DKD. However, the circulating expression and clinical significance of ANRIL in DKD patients is uncertain. This study aims to explore this issue. Methods: The study consisted of 20 healthy controls, 22 T2DM patients (normalbuminuria) and 66 DKD patients (grouped as follows: microalbuminuria, n = 23; macroalbuminuria, n = 22 and renal dysfunction, n = 21). The expressions of ANRIL in peripheral whole blood of all participants were measured by RT-qPCR. Results: The expression of ANRIL was significantly up-regulated in DKD patients (microalbuminuria, macroalbuminuria and renal dysfunction groups) than that in healthy control group. ANRIL was also over-expressed in macroalbuminuria and renal dysfunction groups in comparison with normalbuminuria group. ANRIL expression was positively correlated with Scr, BUN, CysC, urine β2-MG and urine α1-MG; while negatively correlated with eGFR in DKD patients. In addition, ANRIL was the risk factor for DKD with OR value of 1.681. The AUC of ANRIL in identifying DKD was 0.922, and the sensitivity and specificity of DKD diagnosis were 83.3% and 90.5%, respectively. Conclusion: Our results indicated that highly expressed ANRIL in peripheral blood is associated with progression of DKD. Circulating ANRIL is an independent risk factor of DKD and has a highly predictive value in identifying DKD. [ABSTRACT FROM AUTHOR]

Purpose: To report the early experience and mid-term outcomes of physician-modified fenestrated or branched endovascular repair (PM-F/BEVAR) for patients with post-dissection thoracoabdominal aortic aneurysm (PD-TAAA). Methods: PD-TAAA patients treated with PM-F/BEVAR between December 2014 and September 2020 in our institution were retrospectively analyzed. Results: Out of the 39 patients, technical success defined as successful deployment of all stent grafts with patent target vessels (TVs) and exclusion of the lesion without type I or III endoleak was achieved in 35 patients (89.7%). A total of 126 TVs were successfully reconstructed. Thirty-day mortality was 0%. Seven major adverse events occurred including one acute kidney injury, four renal infarctions, one retroperitoneal hematoma and one left renal artery occlusion. Seven type II endoleak and three type III endoleak were detected. During a mean 29.4 ± 15.5 months follow-up period, the mortality was zero. Three renal arteries and one external iliac artery occluded in four patients. No other new onset major adverse event occurred. No patient required reintervention. One type II endoleak spontaneously resolved, while the remaining six remained stable. One early type III endoleak diminished, and one new type III endoleak occurred at 2 months. The primary patency of TV was 96.8% (120/124). Shrinkage or stability of aneurysm diameter can be observed in 38 patients (97.4%). The false lumen thrombosis rate was 89.7% (35/39). Conclusions: The present study showed encouraging results of PM-F/BEVAR for treatment of PD-TAAAs. Level of Evidence: Level 4, Case Series. [ABSTRACT FROM AUTHOR]

Broad-spectrum heterogeneous 1 T/2H MoSe2 homojunction nanosheets were prepared using single-step solvothermal process. The 1 T and 2H phase ratios in the homojunction could be controlled by adjusting the amount of NaBH4. Moreover, the presence of 1 T phase in the 1 T/2H MoSe2 increased the absorption ability of MoSe2 and accelerated electron transport, which greatly enhances the photocatalytic degradation activity under broad-spectrum range. Radical trapping experiments indicated that ·OH and ·O2− radicals are the main active species of methylene blue degradation. Combined with the results of photocatalytic activity and band structure, the photocatalytic mechanism of the 1 T/2H MoSe2 was proposed. [ABSTRACT FROM AUTHOR]

Heterostructures composed of oxides and sulfides (nitrides or carbides) show great potential as sulfur host additives because of the strong adoptability of oxides and catalytic capability of sulfides towards the notorious lithium polysulfides (LiPSs). However, the migration and conversion pathway of LiPSs is seriously confined at a localized interface with inadequate active sites. In this work, the introduction of selenium vacancies into VSe2−x has been demonstrated to successfully synergize the adsorbability and catalytic reactions of LiPSs at an integrated functional surface. The N-doped carbon nanosheets-assembled flower architectures embedded with selenium vacancy-rich VSe2−x and partial vanadium oxides have been controllably synthesized and employed as the cathode additives for lithium-sulfur (Li-S) batteries. Both the experiments and first-principle calculations reveal their strong adsorption to LiPSs and their bidirectional catalytic functionality towards the conversion between S8 and Li2S. As expected, the charge and discharge kinetics of VSe2−x containing sulfur cathodes is fundamentally improved (an outstanding rate capabilitiy with 693.7 mAh·g−1 at 2 C, a remarkable long-term cyclability within 1,000 cycles at 2 C with S loading 2.27 mg·cm−2, and an excellent areal capacity with 3.44 mAh·cm−2 within 100 cycles at 0.5 C). This work presents an effective resolution to couple the adsorbability and catalytic reactions of LiPSs at the material design perspective, and the insights on bidirectional catalytic functionality are of vital to develop functional materials for advanced Li-S batteries. [ABSTRACT FROM AUTHOR]

MXene is a new intercalation pseudocapacitive electrode material for supercapacitor application. Intensifying fast ion diffusion is significantly essential for MXene to achieve excellent electrochemical performance. The expansion of interlayer void by traditional spontaneous species intercalation always leads to a slight increase in capacitance due to the existence of species sacrificing the smooth diffusion of electrolyte ions. Herein, an effective intercalation-deintercalation interlayer design strategy is proposed to help MXene achieve higher capacitance. Electrochemical cation intercalation leads to the expansion of interlayer space. After electrochemical cation extraction, intercalated cations are deintercalated mostly, leaving a small number of cations trapped in the interlayer silt and serving as pillars to maintain the interlayer space, offering an open, unobstructed interlayer space for better ion migration and storage. Also, a preferred surface with more -O terminations for redox reaction is created due to the reaction between cations and -OH terminations. As a result, the processed MXene delivers a much improved capacitance compared to that of the original Ti3C2Tx electrode (T stands for the surface termination groups, such as -OH, -F, and -O). This study demonstrates an improvement of electrochemical performance of MXene electrodes by controlling the interlayer structure and surface chemistry. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries are of significant roles in the next-generation energy storage devices due to the high theoretical capacity and energy density. However, the disturbing shuttle effect, poor conductivity as well as large volume change of the electrode in the cycling process have seriously hindered the practical application. A porous-activated carbon derived from pomelo peel is thus developed with high specific surface area (2326.4 m2 g−1) and abundant N and O heteroatoms to function as host of the S cathode. This porous carbon host originated from the renewable biomass of pomelo peel demonstrates remarkable advantages including higher sulfur accommodation (90% of S in C/S composite), improved conversion kinetics, and suppressed shuttle effect, which endows excellent electrochemical performances. Consequently, the prepared composite with 91.51% sulfur content delivers a high specific discharge capacity of 662.2 mAh g−1 at 1 C as well as a low capacity decay rate of 0.068% per cycle. [ABSTRACT FROM AUTHOR]

Cobalt phosphide (CoP) is considered to be a potential candidate in the field of electrocatalysis due to its low-cost, abundant resources and high electrochemical stability. However, there is a great space for further improvement of its electrocatalytic performance since its charge transfer rate and catalytic activity have not reached a satisfactory level. Herein, we design and fabricate a three dimensional urchins like V-doped CoP with different amounts of V-doping on nickel foam electrode. The V-doped CoP/NF electrode with optimized amounts of V-doping (10%) exhibits outstanding hydrogen evolution reaction (HER) performance under universal-pH conditions and preeminent oxygen evolution reaction (OER) performance in alkaline media. Notably, the assembled water-splitting cell displays a cell voltage of only 1.53 V at 10 mA·cm−2 and has excellent durability, much better than many reported related bifunctional catalysts. The experiment results and theoretical analysis revealed that vanadium atoms replace cobalt atoms in CoP lattice. Vanadium doping can not only raise the density of electronic states near the Fermi level enhancing the conductivity of the catalyst, but can also optimize the free energy of hydrogen and oxygen-containing intermediates adsorption over CoP, thus promoting its catalytic activity. Moreover, the unique nanostructure of the catalyst provides the various shortened channels for charge transfer and reactant/electrolyte diffusion, which accelerates the electrocatalytic process. Also, the in situ growth strategy can improve the conductivity and stability of the catalyst. [ABSTRACT FROM AUTHOR]

Quantitative evaluation of analgesic efficacy improves understanding of the antinociceptive mechanisms of new analgesics and provides important guidance for their development. Lappaconitine (LA), a potent analgesic drug extracted from the root of natural Aconitum species, has been clinically used for years because of its effective analgesic and non-addictive properties. However, being limited to ethological experiments, previous studies have mainly investigated the analgesic effect of LA at the behavioral level, and the associated antinociceptive mechanisms are still unclear. In this study, electrocorticogram (ECoG) technology was used to investigate the analgesic effects of two homologous derivatives of LA, Lappaconitine hydrobromide (LAH) and Lappaconitine trifluoroacetate (LAF), on Sprague-Dawley rats subjected to nociceptive laser stimuli, and to further explore their antinociceptive mechanisms. We found that both LAH and LAF were effective in reducing pain, as manifested in the remarkable reduction of nocifensive behaviors and laser-evoked potentials (LEPs) amplitudes (N2 and P2 waves, and gamma-band oscillations), and significantly prolonged latencies of the LEP-N2/P2. These changes in LEPs reflect the similar antinociceptive mechanism of LAF and LAH, i.e., inhibition of the fast signaling pathways. In addition, there were no changes in the auditory-evoked potential (AEP-N1 component) before and after LAF or LAH treatment, suggesting that neither drug had a central anesthetic effect. Importantly, compared with LAH, LAF was superior in its effects on the magnitudes of gamma-band oscillations and the resting-state spectra, which may be associated with their differences in the octanol/water partition coefficient, degree of dissociation, toxicity, and glycine receptor regulation. Altogether, jointly applying nociceptive laser stimuli and ECoG recordings in rats, we provide solid neural evidence for the analgesic efficacy and antinociceptive mechanisms of derivatives of LA. [ABSTRACT FROM AUTHOR]

Construction of Z-scheme heterostructure is of great significance for realizing efficient photocatalytic water splitting. However, the conscious modulation of Z-scheme charge transfer is still a great challenge. Herein, interfacial Mo-S bond and internal electric field modulated Z-scheme heterostructure composed by sulfur vacancies-rich ZnIn2S4 and MoSe2 was rationally fabricated for efficient photocatalytic hydrogen evolution. Systematic investigations reveal that Mo-S bond and internal electric field induce the Z-scheme charge transfer mechanism as confirmed by the surface photovoltage spectra, DMPO spin-trapping electron paramagnetic resonance spectra and density functional theory calculations. Under the intense synergy among the Mo-S bond, internal electric field and S-vacancies, the optimized photocatalyst exhibits high hydrogen evolution rate of 63.21 mmol∙g−1·h−1 with an apparent quantum yield of 76.48% at 420 nm monochromatic light, which is about 18.8-fold of the pristine ZIS. This work affords a useful inspiration on consciously modulating Z-scheme charge transfer by atomic-level interface control and internal electric field to signally promote the photocatalytic performance. The construction of Z-scheme heterostructures is of great significance for realizing efficient photocatalytic water splitting. Here, the authors report an interfacial chemical bond and internal electric field modulated Z-Scheme Sv-ZnIn2S4/MoSe2 photocatalyst for efficient hydrogen evolution. [ABSTRACT FROM AUTHOR]

Purpose: To establish a reproducible porcine model of ascending aortic aneurysm (AsAA). Methods: We created an AsAA in twelve domestic pigs using a cover-then-cut method, stitching a glutaraldehyde tanned bovine pericardial patch onto the anterolateral aortic wall, then cutting off aortic wall tissue within the patch, and closing the incision in the patch. Results: The AsAA creation was completed successfully in 11 out of the 12 pigs (91.7%). The mean maximal diameter of the ascending aorta increased significantly by 1.77 times, immediately after the operation (p < 0.05). Significantly continuous expansion of the aneurysm was observed during the follow up period, to 48.9 ± 1.80 mm at 3 months and 50.3 ± 2.25 mm at 6 months (p < 0.05). Conclusions: This porcine model of AsAA, created using a repeatable cover-then-cut method, represents a reproducible platform for studying and training, which could contribute to the development of new feasible endovascular treatments of AsAAs. [ABSTRACT FROM AUTHOR]

Adsorption is an effective and low-cost method for removing antibiotics and dyes. However, it remains a challenge to prepare an adsorbent with excellent adsorption properties for both various antibiotics and dyes. Herein, Fe/Cr-codoped ZnO with high adsorption capacity and fast adsorption rate are prepared by an environmentally friendly solvothermal method. Fe/Cr-codope ZnO with a diameter of 10–20nm exhibits superior adsorption capacities for the antibiotics of tetracycline hydrochloride (TC-HCl) (826.45 mg g−1) and tetracycline (TC) (331.01 mg g−1), and anionic dyes of methyl orange (MO) (1023.88 mg g−1), methyl blue (MB) (726.26 mg g−1) and direct red (DR) (642.25 mg g−1). Meanwhile, it presents fast adsorption rate, it only took 30min to reach more than 90% of the equilibrium adsorption amount for TC-HCl, TC, MO, MB and DR. The adsorption process closely fitted the Langmuir isotherm model and pseudo second-order rate equation. More importantly, simple method has been developed for separating the pollutant from the adsorbent, which not only regenerates the materials, but also completes the recovery of antibiotics and dyes, avoiding the secondary pollution. The broad-spectrum, rapid, environment-friendly and effective adsorption properties make Fe/Cr-codoped ZnO a promising adsorbent for water treatments. [ABSTRACT FROM AUTHOR]

Nickel sulfide nanoworm (Ni3S2 NW) network architecture was directly grown on the poly (3,4-ethylenedioxythiophene)-reduced graphene oxide hybrid films (PEDOT-rGO HFs) modified on glassy carbon electrode (GCE), acting as a binder-free sensor for high-performance non-enzymatic glucose monitoring. The sensor exhibited the satisfactory sensitivity (2123 μA mM−1 cm−2), wide linear range (15~9105 μM), low detection limit (0.48 μM), and rapid response time (< 1.5 s) at a potential of 0.5 V (vs. SCE) in 0.1 M NaOH and possessed good selectivity, reproducibility, and stability. The enhanced electrocatalytic activity of the sensor towards glucose oxidation was attributed to the particular morphology, satisfying hydrophilic nature, strong combination between Ni3S2 NWs, PEDOT-rGO, and bare GCE. Moreover, it can be used for assaying glucose in human serum samples without dilution, indicating potential for clinical diagnostic applications. [ABSTRACT FROM AUTHOR]

Purpose: This study was aimed to develop and conduct an Omaha system-based continuing nursing program for chronic kidney disease (CKD) patients undergoing peritoneal dialysis (PD) and to explore its effect on patients' nutritional status. Methods: A randomized controlled trial was performed in a teaching hospital in China between June 2017 and July 2018. A total of 203 eligible patients were included and then randomly assigned to the study group (n = 101) or the control group (n = 102). In the study group, health education, treatments and procedures, case management, and surveillance based on the Omaha system were used. In the control group, only common outpatient nursing intervention was given to the patients. Changes in subjective global assessment (SGA), anthropometric measurements including body mass index (BMI), triceps skin-fold thickness (TSF), mid-arm muscle circumference (MAMC), and handgrip strength (HGS), and biochemical parameters (hemoglobin, albumin, pre-albumin, total cholesterol, and creatinine) were evaluated before the intervention and 6 months after the intervention and differences in measurements were analyzed. Results: After intervention, the proportion of well-nourished patients in the study group was significantly improved from 6.19 to 29.90% (χ 2 = 18.441, P < 0.001), and after 6 months, this was higher in the study group than that in the control group (29.90% vs 9.28%, χ 2 = 13.090, P < 0.001). Also, mean TSF, MAMC, and HGS were significantly improved in the study group and after 6 months, these levels were higher in the study group than those in the control group (P < 0.05). In addition, levels of hemoglobin, albumin, and pre-albumin in patients in the study group were significantly increased and after 6 months, these levels were higher in the study group than those in the control group (P < 0.05). Conclusions: The continuing nursing program based on the Omaha system improved patients' nutritional status and should be further examined in future studies. [ABSTRACT FROM AUTHOR]

In this paper, Co9S8/Ni3S2 nanoflakes (NFs) with sulfur deficiencies were grown in-situ on N-doped graphene nanotubes (N-GNTs). They were successfully prepared through electrodeposition followed by hydrogenation treatment, which is able to act as a self-supported electrode for asymmetric supercapacitors (ASCs). Combining the defect-rich active materials with highly conductive skeletons, the hybrid electrode N-GNTs@sd-Co9S8/Ni3S2 NFs show ultrahigh specific capacity of ∼304 mA h g−1 and prominent rate capability (capacity retention ratio of ∼85% even at 100 A g−1), and deliver a long cycling lifespan of ~1.9% capacitance loss after 10000 cycles. In addition, an ASC was constructed using the as-synthesized composite electrode as the positive electrode and active carbon (AC) as the negative electrode. The fabricated device shows a high energy density of ~45.1 Wh kg−1 at ~3.4 kW kg−1 and superior cycling stability. This work substantiates a smart strategy to fabricate novel composite electrode materials for next-generation supercapacitors by incorporating riched deficiencies into nanostructures. [ABSTRACT FROM AUTHOR]

To achieve high-performance supercapacitors, electrode materials with the accessible electrode area, electrons, and ions diffusion channels are strongly needed. Herein, the network-like holey NiCo2O4 nanosheet arrays grown on Ni foam have been synthesized by a facile and efficient electrodeposition followed by calcination as a binder-free electrode for supercapacitors. The nanosheets are interconnected and interlocked together to form a network-like structure with abundant open channels, and the arrays are about 2.3 μm in thickness. Interestingly, the holey nanosheets include numerous macropores (50-160 nm) and mesopores (3-10 nm), which contribute to the rapid electrolyte ions diffusion between the nanosheet layers and the increase of capacitances. The NiCo2O4 nanosheet arrays electrode displays a high capacitance of 2.23 F cm−2 (1012.5 F g−1) at a current density of 5 mA cm−2, good rate capability of 67.3% at a current density of 50 mA cm−2, and high-cycling stability. These results indicate that the network-like holey NiCo2O4 nanosheet arrays electrode has a significant potential application in supercapacitors. [ABSTRACT FROM AUTHOR]

Porous composite nanofibers consisted of cubic Bi12TiO20, and orthorhombic Bi4Ti3O12 with pore size of 5-10 nm have been successfully synthesized by combining electrospinning with calcination for photodegrading methyl orange (MO). Calcination temperature has a great effect on the ratio of Bi12TiO20 and Bi4Ti3O12 and their morphology, which in turn affects the photocatalytic property of the products. MO was almost completely degraded over the as-prepared samples obtained under the optimizing calcination temperature of 500 °C after irradiating for 40 min under simulated sunlight. Besides, cycle and regeneration experiments show that the porous Bi12TiO20/Bi4Ti3O12 composite nanofibers possess fine cycle stability and regeneration ability, after the regenerative photocatalyst was recycled twice, 91% of the MO was degraded. Based on the characterization results, the mechanism of the improvement in photocatalytic property of Bi12TiO20/Bi4Ti3O12 composite nanofibers was also investigated, and h+ played a major role in the photodegradation of MO. In addition, the as-prepared Bi12TiO20/Bi4Ti3O12 composite nanofibers show a certain capacity of photocatalytic hydrogen production under the simulated sunlight. This work not only provides a porous fiber with good photocatalytic activity, but also provides a reference for the preparation and performance study of other fibers. [ABSTRACT FROM AUTHOR]

Tobacco smoke contains various toxic heavy metals that individuals are exposed to when they smoke. Despite the presence of heavy metals in tobacco smoke, the relationship between smoking and the accumulation of toxic metals in pregnant women after long-term exposure remains under discussion. We examined the association between long-term exposure to tobacco smoke and the accumulation of toxic metals in the hair of female participants. Our study recruited 252 women from the Shanxi and Hebei provinces of Northern China; these participants were self-reported non-active smokers, and had previously delivered healthy babies without birth defects. Scalp hair was collected and analyzed for nicotine and cotinine and five potentially toxic metals (specifically, silver, chromium, cadmium, mercury, and lead). Our results showed significant positive correlations between cotinine and four metals, including silver (r = 0.369, p < 0.001), cadmium (r = 0.185, p < 0.01), mercury (r = 0.161, p < 0.05), and lead (r = 0.243, p < 0.001). Significant positive correlations were also found between nicotine and three metals—specifically silver (r = 0.331, p < 0.001), cadmium (r = 0.176, p < 0.01), and lead (r = 0.316, p < 0.001). A logistic regression model showed significant associations between cotinine and potentially toxic metals including mercury, silver, and lead (with or without adjusting for potential confounders). We thus conclude that long-term passive smoking could potentially increase the exposure level of toxic metals including lead, silver, and mercury in our study, which are especially harmful for pregnant women and their unborn fetus. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) have been recently shown to be dysregulated and closely related to several cancers. Here, we aimed to elucidate the function and the possible molecular mechanisms of lncRNA Metastasis-associated lung Adenocarcinoma transcript-1 (MALAT1) in human glioma. Quantitative real-time PCR (qRT-PCR) was used to detect the expressions of MALAT1, miR-101 and Rap1B mRNA in U251 and U87 cells. The protein level of Rap1B was examined by western blot assays. Moreover, the proliferation and apoptosis of U251 and U87 cells were determined by CCK-8 assay and flow cytometry analysis, respectively. Additionally, the targets of miR-101 were identified by target prediction and luciferase reporter assays. The results demonstrated that MALAT1 and Rap1B were upregulated, while miR-101 expression was downregulated in glioma cell lines U251 and U87. MALAT1 and Rap1B knockdown could inhibit proliferation and induce apoptosis of glioma cells. Moreover, MALAT1 promoted the Rap1B expression by sponging miR-101 in U251 and U87 cells. Furthermore, miR-101 downregulation or Rap1B overexpression reversed the proliferation inhibitory and apoptosis induction of glioma cell lines caused by MALAT1 knockdown. Taken together, MALAT1 promotes proliferation and suppresses apoptosis of glioma cells through derepressing Rap1B by sponging miR-101. The present study elucidates a novel MALAT1-miR-101-Rap1B regulatory axis in glioma, contributing to a better understanding of the glioma pathogenesis and providing a promising therapeutic target for glioma patients. [ABSTRACT FROM AUTHOR]

Catalysis by silver nanoparticles (Ag-NPs) in organic transformations has received growing attention due to their unique reactivity and selectivity. Herein, we investigated a versatile one-step approach for synthesizing thermally stable AgNPs using catechol (1,2-benzenediol) without additional reducing and stabilizing agents in aqueous solution. In an alkaline environment, oxidation of catechol played a dual role in the reduction of silver ions (Ag) and stabilization of the AgNPs. Nanoparticles with different size and morphology were obtained under different experimental conditions. X-ray diffraction (XRD) analysis suggests the formation of crystalline AgNPs of average size 13, 38 and 47 nm and face centered cubic structure as the reaction pH varied. As demonstrated in dynamic light scattering (DLS) and scanning electron microscopy (SEM) images, AgNPs with uniform size distribution (50 nm) were synthesized at pH 11. The nanoparticles are thermally stable with a steady loss of weight up to 800 °C as confirmed by thermogravimetric analysis (TGA). Comparing to AgNPs@pH5 and AgNPs@pH8, AgNPs synthesized at pH 11 have shown significant catalytic activity in the reduction of 4-nitrophenol (4 -NP) to 4-aminophenol (4-AP) with 61% conversion at 20 °C. The results suggested that stable and monodisperse nanoparticles with tunable catalytic activity could be produced as the pH of the reaction was altered. Graphical Abstract: [ABSTRACT FROM AUTHOR]

The authors describe the fabrication of a nanocomposite consisting of reduced graphene oxide, zinc oxide and silver nanoparticles by microwave-assisted synthesis. The composite was further reduced in-situ with hydrazine hydrate and then placed, along with the enzyme glucose oxidase, on a glassy carbon electrode. The synergistic effect of the materials employed in the nanocomposite result in excellent electrocatalytic activity. The Michaelis-Menten constant of the adsorbed GOx is 0.25 mM, implying a remarkable affinity of the GOx for glucose. The amperometric response of the modified GCE is linearly proportional to the concentration of glucose in 0.1 to 12.0 mM concentration range, and the detection limit is 10.6 µM. The biosensor is highly selective, well reproducible and stable. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

To understand the solidification processes of natural magma and the texture evolution of igneous rocks, we have carried out in situ observation of the crystallization of a high-K basaltic melt cooling from ~1,240 °C in a moissanite cell. In a series of experiments with different thermal history, olivine or clinopyroxene (cpx) appeared as the liquidus phase before the formation of plagioclase. During cooling at 100 °C/h, the morphology of olivine and cpx transited from tabular to hopper habit. To first order approximation, crystal grow rate (2 × 10 to 7 × 10 m/s for olivine and 6 × 10 to 17 × 10 m/s for cpx), probably limited by chemical diffusion, is proportional to crystal size. In one experiment dominated by olivine crystallization, the good image quality allows the analysis of texture evolution over an extended period. Nucleation of olivine occurred only in a narrow temperature and time interval below the liquidus. Two-dimensional length- and area-based crystal size distributions (CSDs) show counterclockwise rotation around axes of 8 μm and 100 μm, which is consistent with the proportionate crystal growth. Both CSDs and direct observation show the dissolution of small crystals and Ostwald ripening. These data suggest that conventional analyses of crystal size distributions of igneous rocks may be in error-the slope of the CSD cannot be interpreted in terms of a uniform growth rate, and the intercept with the vertical axis does not correspond to a nucleation density. [ABSTRACT FROM AUTHOR]

SiC nanowires with thickness-controlled SiO shells have been obtained by a simple and efficient method, namely treatment of SiC/SiO2 core-shell nanowires in NaOH solution. The products were characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Raman spectroscopy, infrared (IR) spectroscopy, and photoluminescence spectroscopy. The thickness of the SiO shell can be effectively controlled by selecting the appropriate processing time, and pure SiC nanowires were also obtained by alkaline cleaning in 1 mol·L NaOH solution for 40 min at 70 °C. A mechanism for the removal of the SiO shells has been proposed, and a two-phase reaction kinetic equation was derived to explain the rate of the removal of the SiO shells. The validity of this equation was verified by experiment. This work not only describes an effective experimental method for achieving SiC nanowires with thickness-controlled SiO2 coatings but also provides a fundamental theoretical equation with a certain level of generality. In addition, photoluminescence (PL) measurement results showed that the SiC nanowires sheathed with an optimum SiO thickness (3.03 nm) have better photoluminescence properties than either the bare SiC nanowires or SiC nanowires with thicker coatings of SiO. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A novel high-effective sunlight-induced AgBr/ZnO hybrid nanophotocatalyst has been synthesized and it was characterized by different techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and ultraviolet-visible spectrophotometry (UV-vis). The AgBr/ZnO hybrid nanophotocatalyst has excellent photocatalytic activity for photodegradation of methyl orange (MO) under sunlight irradiation. The MO degradation efficiency for AgBr/ZnO is about 98% after 1 hour under sunlight irradiation. These results suggested that AgBr/ZnO is a promising candidate for the development of highly efficient sunlight photocatalysts. In addition, the photocatalytic mechanism of AgBr/ZnO under sunlight irradiation is illustrated and discussed. [ABSTRACT FROM AUTHOR]

lthough the SiC/SiO nanochain heterojunction has been synthesized, the chained homogeneous nanostructure of SiC has not been reported before. Herein, the novel β-SiC nanochains are synthesized assisted by the AAO template. The characterized results demonstrate that the nanostructures are constructed by spheres of 25-30 nm and conjoint wires of 15-20 nm in diameters. Raman and photoluminescence measurements are used to explore the unique optical properties. A speed-alternating vapor-solid (SA-VS) growth mechanism is proposed to interpret the formation of this typical nanochains. The achieved nanochains enrich the species of one-dimensional (1D) nanostructures and may hold great potential applications in nanotechnology. [ABSTRACT FROM AUTHOR]

The perovskite-type oxide catalyst LaMnO3 prepared by the sol–gel method was found to be an efficient heterogeneous and recyclable catalyst for the wet aerobic oxidation of lignin to aromatic aldehydes. The lignin conversion rate and the yield of each aromatic aldehyde were enhanced significantly by the catalytic process as compared with the non-catalyzed process. Moreover, the activity, specific surface area and perovskite-type structure of the LaMnO3 catalyst remained nearly unchanged after five successive recycles of catalytic reactions. [ABSTRACT FROM AUTHOR]