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Layered transition metal oxide Na 0·67 Fe 0·5 Mn 0·5 O 2 is considered as a promising cathode material of sodium-ion batteries because of its naturally elemental abundance and high energy density. However, low rate capability and poor structural reversibility of Na 0·67 Fe 0·5 Mn 0·5 O 2 greatly hinder its large scale application. In this study, V-substituted Na 0·67 Fe 0·5 Mn 0·5 O 2 cathode material with improved electrochemical performance is successfully synthesized via a sol-gel method. The effects of V-substitution on chemical composition, crystal structure and morphology of Na 0·67 Fe 0·5 Mn 0·5 O 2 are studied in detail. Furthermore, modification mechanisms on the improved electrochemical performance by V-substitution are investigated. The results demonstrate that the rate capability and cycle stability of Na 0·67 Fe 0·5 Mn 0·5 O 2 cathode material is significantly elevated by V-substitution. And the enhanced electrochemical properties are mainly attributed to the improved Na+ diffusion rate and structural reversibility. This study suggests that introducing V ions into the lattice of Na 0·67 Fe 0·5 Mn 0·5 O 2 crystals is a favorable strategy to improve its electrochemical properties. [ABSTRACT FROM AUTHOR]

Black phosphorus is a potential candidate material for next-generation energy storage devices and has attracted tremendous interest because of its advantageous structural and electrochemical properties, including its large theoretical capacity, high carrier mobility, and low redox potential. However, its practical applicability has remained low owing to its difficult of preparation, large volume expansion during cycling, and poor electronic conductivity. To this end, there have been significant efforts to improve its synthesis methods and electrochemical performance. A number of black-phosphorus-based composite materials have been developed and investigated. Herein, we provide an up-to-date account of the recent progress made in research on black-phosphorus-based materials for use in rechargeable batteries and supercapacitors. We review the available synthesis methods and basic properties of black phosphorus and discuss its applicability in Li-, Na-, K-, Mg-, Al-ion and Li-S batteries as well as supercapacitors. We also summarize the existing challenges and future opportunities and offer our perspective on the possible directions for future research in this area. [ABSTRACT FROM AUTHOR]

In this work, highly pure nano-TiO 2 photocatalysts with varying Fe doping concentration were successfully synthesized from low-cost Ti-bearing tailings by an acidolysis-hydrothermal route. The effects of H 2 SO 4 concentration, leaching temperature, acid/tailings ratio and leaching time on the recovery of TiO 2 from the tailings were investigated. Synthesized samples were characterized by XRD, TEM, EDS, XPS, and UV–vis spectroscopy. The results showed that the material prepared is characteristic anatase with the average size of 20 nm and the Fe doping concentration in the synthesized nano-TiO 2 is tunable. The photocatalytic activity of synthesized nano-TiO 2 photocatalyst was also evaluated by the photodegradation of Rhodamine B under visible light and UV light irradiation. Our study demonstrates a low-cost approach to synthesize highly efficient and visible light responsive catalysts. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a combined-method study has been made on the lateral muscle of the teleost olive flounder Paralichthys olivaceus in just-hatched and adult stages. In just-hatched stage, both slow and fast muscle fibres were detected: (1) in situ hybridization analysis indicated that slow and fast myosin heavy chain genes were specifically expressed in the superficial and deep part of the myotomal muscle, respectively; (2) immunohistochemistry analysis showed that fibres in the deep part reacted with anti-fast myosin antibody F310; (3) western blot analysis detected a weak expression of slow myosin and a strong expression of fast myosin. In adult stage, the slow and fast muscle fibres had their own distribution characteristics: (1) hematoxylin/eosin staining showed the histological characteristics of the muscle fibre composition; (2) histochemical observations showed that the deep muscle fibres, and some fibres near the epidermis, contain alkali-stable myofibrillar ATPase activity; (3) immunohistochemistry analysis indicated that all the deep muscle fibres reacted with F310 antibody and some fibres in the superficial layer of muscle also reacted with F310; (4) western blot analysis showed that fast myosin was expressed both in the blended muscles (the mix of superficial and deep muscles) and deep muscles, while slow myosin was mainly expressed in the blended muscles. These findings suggested that both slow and fast muscle fibres existed in the musculature of the olive flounder in just-hatched and adult stages. Notably, the adult fast fibres also exist in the superficial layer of the muscle. [ABSTRACT FROM AUTHOR]

There are several challenges (e.g., imbalance between supply and demand of hardware resources and software licenses, and usability) under modern High-Performance Computing (HPC) environment. As a means of providing an on-demand service for end users, we propose a Software-as-a-Service (SaaS) approach for managing commercial HPC applications as a Web-based service deployed on top of federated clouds. Some inter-trusted private or public clouds are federated to create a unified service platform with a large amount of hardware resources. In addition, an on-demand, pay-per-use model for Web-service-enabled HPC applications is proposed. Further, we provide an economic analysis of the proposed approach from the perspective of end users, cloud service providers, and Independent Software Vendors (ISVs). We conduct a simulation using two HPC application services on three federated clouds. A combined Quality of Service (QoS) and economic evaluation demonstrates a better effect of the proposed approach comparing with existing HPC platforms. [ABSTRACT FROM AUTHOR]

For the first time, a one-step synthetic strategy has been developed towards the preparation of Ti 3+ self-doped TiO 2 with internal-pores and highly exposed {001} facets using ethylene glycol (EG) and HF as control agents. The obtained samples were characterized by XRD, XPS, SEM, TEM, HAADF-STEM, photoluminescence spectroscopy (PL), and UV–vis reflectance spectroscopy. The synergistic effect of EG and HF plays a vital role in the formation of synthesized TiO 2 with Ti 3+ self-doping, internal-pores and highly exposed {001} facets. As-synthesized TiO 2 exhibit much higher activity than commercial P25 on photocatalytic degradation of phenol and the outstanding performance is attributed to the synergistic effect of Ti 3+ doping, internal-pores, and facets heterojunction. [ABSTRACT FROM AUTHOR]

Na 2 MnPO 4 F has become a promising cathode candidate for next generation sodium ion batteries by virtue of its high working potential and theoretical capacity, but its electrochemical performance is restricted by its low electronic conductivity and sluggish Na+ diffusion. In this study, Na 3 V 2 (PO 4) 2 F 3 is introduced into the Na 2 MnPO 4 F cathode material to improve the electron/ionic conductivity by generating lattice defects and providing active sites for Na+ transportation. The structure, morphology and electrochemical properties of x Na 2 MnPO 4 F· y Na 3 V 2 (PO 4) 2 F 3 /C materials are investigated thoroughly. It is found that the electrochemical performance of Na 2 MnPO 4 F is significantly elevated by the modification of Na 3 V 2 (PO 4) 2 F 3. The optimized lotus root-like porous Na 2 MnPO 4 F·Na 3 V 2 (PO 4) 2 F 3 /C cathode material delivers the first specific discharge capacity of 126.6 mAh·g−1 at 0.05C, which is close to the theoretical specific capacity. Furthermore, the Na 2 MnPO 4 F·Na 3 V 2 (PO 4) 2 F 3 /C cathode material also presents good rate performance (76.9 mAh·g−1 at 1C rate), and remains 93.2% capacity retention after 400 cycles. This paper demonstrates a promising guide to construct Na 2 MnPO 4 F-based cathode materials with superior electrochemical performance for sodium ion batteries. [Display omitted] [ABSTRACT FROM AUTHOR]

In teleost fish, primordial germ cells (PGCs) are specified very early during embryogenesis and migrate to the site that gonads are formed. A previous study indicated that nanos3 is specifically expressed in PGCs, and the 3′ untranslated region (UTR) of nanos3 is responsible for the localization of mRNA in these cells. In this study, we aimed to investigate the functional regions of nanos3 3′UTR in olive flounder using truncated and mutated nanos3 3′UTRs fused to chimeric RNAs and microinjected into fertilized zebrafish eggs. The results indicated that a 68-bp functional element in the nanos3 3′UTR of olive flounder played important roles in the protection and degradation of RNA. Within this element, a U-rich region was identified to be responsible for the protection of RNA in PGCs and two GCAC sites for the degradation of RNA in somatic cells. The first GCAC was located adjacently to the U-rich region and the second GCAC within the U-rich region. Overall, we concluded that the two GCACs were the binding sites of miR-430, a microRNA that suppresses translation, whereas the U-rich region was the binding site of Dnd, a protein that antagonizes the miR-430-mediated silencing of mRNA. [ABSTRACT FROM AUTHOR]

A cohesive architecture of 1T-MoS 2 covered by PPy composite (1T-MoS 2 @PPy) is successfully fabricated by a simple hydrothermal reaction followed by an in-situ polymerization route. The composite material consists of 1T-MoS 2 hollow microsphere and conductive PPy coating layer. The cohesive architecture enables the composite to show rapid shuttle of electrons/lithium ions and good ductility to buffer the volume changes during charging and discharging process when it is used as anode material. As expected, 1T-MoS 2 @PPy composite exhibits a favorable discharge capacity up to 970.3 and 407.1 mAh g−1 at 0.2 and 3 A g−1, respectively. In addition, the composite also achieves impressive cycling performance of 717.1 mAh g−1 at 1 A g-1 after 500 cycles. This study provides a meaningful guidance in rational design of anode materials with cohesive architecture as well as high electrochemical performance. [ABSTRACT FROM AUTHOR]

It is a great challenge to develop the cathode materials with high efficiency, long life and low-cost for lithium-sulfur batteries. In this paper, we design a simple hydrothermal method to synthesize MoS 2 wrapped the MOFs-derived N-doped carbon nanorods as an effective sulfur host to improve the electrochemical performance of lithium-sulfur batteries. In the hydrothermal process, the cubic zeolitic imidazolate framework-67 (ZIF67) particles are connected together to form nanorods, and MoS 2 nanosheets are wrapped on the surface of the nanorods. In this composite, the carbon nanorods derived from ZIF67 is the main host for S-loading, while N-doping can change the hybrid orbital form of carbon and significantly improve the chemical adsorption of polysulfide. The elemental cobalt and cobalt oxide derived from ZIF67 can improve the electronic conductivity and polarity of the composite. And MoS 2 coating layer can provide more active sites, accelerate the sulfur redox reactions and effectively restrain the shuttle effect. The synergetic effects of above-mentioned factors make the MoS 2 @CZIF67/S composite cathode material shows excellent electrochemical performance. The composite shows high reversible specific capacities of 1391.9 and 806.1 mAh g−1 at 0.1C and 1C rate, respectively, and exhibits a capacity retention of 70.5% after 400 cycles at 1C rate. [ABSTRACT FROM AUTHOR]

A novel process to prepare titanium dioxide from Ti-bearing electric furnace slag by NH 4 HF 2 -HF leaching and hydrolyzing process has been developed. In this present study, the effects of [NH 4 + ]/[F] mXolar ratio, leaching temperature, [F] concentration, liquid/solid mass ratio, leaching time on the Ti extraction, and the phase transformations have been investigated to reveal the leaching mechanism of Ti-bearing electric furnace slag in NH 4 HF 2 -HF solution. In the NH 4 HF 2 -HF leaching process, the MgTi 2 O 5 and Al 2 TiO 5 are converted to TiF 6 2− and Mg-Al-bearing precipitate. Ti extraction rate reached 98.84% under the optimal conditions. In addition, 98.25% iron ions can be removed in the presence of NaCl prior to hydrolysis process. The effects of pH and temperature on the selective hydrolysis of TiF 6 2− during hydrolysis process were also studied. In the hydrolysis process, the TiF 6 2− is converted to (NH 4 ) 2 TiOF 4 . By calcination, high grade TiO 2 powder with its purity of 99.88% was obtained, using which the products, well crystallized anatase and rutile, were obtained through roasting at 800 °C and 1000 °C, respectively. [ABSTRACT FROM AUTHOR]

PAX are important regulators of developmental processes. PAX7 plays crucial roles in patterning of the dorsal central nervous system (CNS), neural crest (NC), and skeletal muscle. Here, we identified six spliced isoforms of pax7a and one pax7b and characterized their expression patterns. All of flounder Pax7a-1, Pax7a-2, Pax7a-3, and Pax7b contain a conserved paired domain (PD), an octapeptide motif (OP), and a paired type homeodomain (HD). However, the PD of Pax7a-4 and the HD of Pax7a-5 are not intact, and there is no HD in Pax7a-4 and Pax7a-6. pax7a and pax7b show distinct spatiotemporal expression patterns during embryogenesis. Whole-mount in situ hybridization demonstrates that the expression patterns of pax7a and pax7b are overlapping but distinguishable in the dorsal central nervous system. pax7a is expressed in most part of the brain and the neural tube, while pax7b is expressed exclusively in the diencephalon and the midbrain. In addition, pax7a is also expressed in the cranial NC and the trunk NC. RT-PCR results show that there were different expression patterns between the different isoforms. These results indicate subfunction partitioning of the duplicated pax7 genes. The duplicated pax7 may provide additional flexibility in fine-tuning neurogenesis and somitogenesis. [ABSTRACT FROM AUTHOR]