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Reducing cobalt dependency has attracted great interest for lithium batteries manufacturing due to limited cobalt resources and high prices. A highly promising LiNi0.6Co0.05Mn0.35O2 (NCM60535) high-nickel low cobalt lithium layered oxide cathode material is successfully prepared by systematically examining the two key synthesis conditions of pH and annealing temperature. The obtained materials exhibit a uniform size distribution, good spherical morphology, clear structure, and homogeneous element distribution. NCM60535 shows competitive electrochemical properties: when compared with the LiNi1/3Co1/3Mn1/3O2, with a higher output specific capacity and cycling stability at 4.3 V low voltage; when compared with the LiNi0.8Co0.1Mn0.1O2, with a comparable discharge capacity but relatively poor cycling stability at 4.5 V high voltage. A new type of electrolyte that combines high lithium salt concentration, EC-free solvent system, and VC and LiPO2F2 functional additives is designed and greatly improves the electrochemical properties of the material under high voltage. Moreover, it also delivers superior electrochemical properties in high voltage lithium full battery (270 Wh Kg−1). And we suggest that NCM60535 is expected to become a substitute for the currently widely commercialized LiNi1/3Co1/3Mn1/3O2 (NCM333), LiNi0.5Co0.2Mn0.3O2 (NCM523), LiNi0.6Co0.2Mn0.2O2 (NCM622), and LiNi0.8Co0.1Mn0.1O2 (NCM811) due to its relatively low production cost and competitive electrochemical properties.

The α-AlH3 + nCeO2 (n = 0.5, 1 and 2, mol%) composite materials were prepared by ball milling, and the phase composition and dehydrogenation performance of the composites were investigated. The results revealed that α-AlH3 doped with CeO2 could effectively decrease the dehydrogenation temperature. The dehydrogenation onset temperature of α-AlH3 + 2 mol% CeO2 dropped to 106 °C, which was significantly reduced by 24.3% compared with pure α-AlH3. At 100 °C, the α-AlH3 + 2 mol% CeO2 composite released 3.8 wt% hydrogen within 100 min, while the pure α-AlH3 released only 0.12 wt% hydrogen in the same duration. Kissinger analysis indicated that apparent activation energy for hydrogen desorption of α-AlH3 was significantly decreased with CeO2 doping. The improvement of dehydrogenation performance was due to the finely dispersed CeH2+x, which was formed by the reaction between CeO2 and α-AlH3.

With the purpose to settle the aggregation and conductivity issues of the active materials, the metal disulfides (MS2, M = Fe, Co) nanoparticles in-situ encapsulated by amorphous carbon layers (MS2@C) have been synthesized by directly vulcanizing the iron (III) acetylacetonate or cobalt (II) acetylacetonate, which are both the metal source and carbon source, using sulfur power as S source and dispersant by a facile one-step heating method. A structure that MS2 nanoparticles are well wrapped by amorphous carbon layer uniformly coated by many ultra-small MS2 nanoparticles is obtained. Benefiting from the unique multidimensional structure that integrates the advantages of low-dimensional nanostructures and high-dimensional bulk structure, FeS2@C and CoS2@C composites evaluated as electrode materials for lithium storage exhibit superior electrochemical performance. After 100 charge-discharge cycles, this novel FeS2@C architecture delivers a reversible capacity of 829 mAh g−1 at 100 mA g−1. Moreover, a high specific capacity of 480 mAh g−1 for FeS2@C at 1000 mA g−1 after 500 cycles is obtained. As for CoS2@C composite, a high specific capacity of 481 mAh g−1 at 500 mA g−1 after 300 cycles is still displayed. This remarkable cycling property and superior rate capability demonstrate the potential applications for next-generation lithium-ion batteries.

Two-dimensional morphological (2DM) metal oxides are highly desirable for the improvement of electrochemical performance of lithium-ion batteries (LIBs). Herein, a facile and scalable strategy to fabricate porous 2DM zinc-cobalt oxide (ZCO) plates is reported, with the help of a morphology-maintained annealing treatment of metal organic frameworks (MOFs). Through change the proportion of metal nitrates in the precursors, a series of porous ZCO plates are synthesized. Thanks to the porous structure, 2DM morphological features and nanosized building block of Co3O4 plates, the Co3O4 plates electrode as anode materials for LIBs display the high reversible capacity (1027 mA h g-1 at 100 mA g−1 after 100 cycles), remarkable rate capability (541 mA h g-1 even at 1000 mA g−1). Furthermore, this strategy of synthesizing the ZCO plates with MOFs provides a new approach to design bimetallic transition metal oxides that the ratio of transition metal is continuously adjusted and has great lithium storage properties.

Novel hybrid transition metal phosphides with elaborate designed architectures are long pursued to improve their lithium-ion storage properties. Here, nanocomposite of Fe x Ni 2-x P particles and P-doped carbon (P-C) substrate has been successfully synthesized through a one-step low-temperature phosphidation of Fe 2 Ni MIL-88 nanorods. In this nanocomposite, the nano-sized Fe x Ni 2-x P particles are embedded into the P-doped carbon nanorods substrate, integrating the high capacity of Fe x Ni 2-x P and the excellent conductivity of P-doped carbon together. When used as anode material for lithium-ion batteries, the nanocomposite exhibits a high reversible capacity of 775 mA h g −1 after 400 cycles at a current density of 100 mA g −1 . Even at a high current density of 2000 mA g −1 , a discharge capacity of 360 mA h g −1 could still be maintained. This excellent electrochemical performance may be attributed to the nano-sized building blocks of Fe x Ni 2-x P particles and the improved conductivity contributed by P-doped carbon substrate as well as the strong interaction between Fe x Ni 2-x P and carbon. Furthermore, this strategy of synthesizing the Fe x Ni 2-x P/P-C nanorods with metal-organic frameworks as a starting point can be extended to design other bimetallic transition metal phosphides with superior lithium storage properties.

To study age-related changes in the morphology of the supratubal recess (STR) and its relationship with the Eustachian tube (ET).Seventy randomly selected computed tomography (CT) images of non-pathological temporal bones of 49 patients were reviewed retrospectively. The patients were grouped according to age into 4 age groups: group A (0-3 years), group B (4-8 years), group C (9-18 years) and group D (19-50 years). Space analytic geometry was assessed to directly calculate the morphology of the STR and the ET.In normal temporal bones, the STR was mostly presented with a solitary cell in life. The length of the STR was significantly longer in group C than that in group A (P0.05). The width of the STR was declined with age and presented with significant difference among age groups (P0.05). No significant difference was observed in the height of the STR in whole age groups (P0.05). The aeration of the STR was intimately related with age-related morphological changes in the ET. But the important factors influencing the aeration of the STR were not always the same in different age stages.The extended length and declined width of the STR with age were mostly related with the prolonging bony part and inwardly bending cartilaginous part of the ET in children and adolescent aged from 0 to 18 years old. In adults aged more than 18 years old, the narrowed caliber of the tympanic orifice of the ET could induce the decline in the width of the STR with age, but unfolded horizontal cartilaginous part of the ET contributed to stable length and height in aeration of the STR.

Hybridizing nanostructured metal oxides with reduced graphene oxide (RGO) is highly appropriate for the improvement of electrochemical performance of lithium-ion batteries (LIBs). Herein, a NiAl-layered double hydroxide (LDH) is vertically grown on a RGO by the microwave-assisted method without any surfactant or template. The NiAl-LDH/RGO is used as precursor to synthesize sandwich-like porous Al 2 O 3 /RGO anchoring NiO nanocomposite (NiO-Al 2 O 3 /RGO) by subsequent calcination and etching process. Furthermore, doping Al 2 O 3 can prevent active materials from agglomeration and generate porous structure in etching process. When used as anode materials for LIBs, the nanocomposite exhibits a high reversible capacity after 100 charge-discharge cycles at a current density of 100 mA g −1 . Even at 500 mA g −1 , a stable capacity as high as 704 mA h g −1 could be obtained. The enhanced lithium storage performance is mainly ascribed to the presence of the conductive RGO and Al 2 O 3 buffer phase, which can relieve structural collapse and offer high conductivity.

Our aims were to measure and compare anatomical parameters of the ossicles in normal, congenital aural stenosis (CAS), and congenital aural atresia (CAA) ears.This retrospective study was performed using three-dimensional reconstructed images derived from computed tomography scans of 20 normal subjects, 20 CAS patients, and 20 CAA patients.The lengths of the malleus handle and long process of the incus were greater in normal ears than in CAS and CAA ears (all P 0.05). The angles of the incudostapedial joint and between the short and long processes of the incus were smaller in normal ears than in CAS and CAA ears (all P 0.05). There were no significant differences in the positions of the malleus head and incudomalleolar joint, the size of the malleus head, the length of the short process of the incus, or the angle of the incudomalleolar joint (P 0.05).Anatomical parameters of the lower part, but not of the upper part, of the ossicular chain in CAS and CAA ears differed from those in normal ears. Different branchial arch origins of the upper and lower parts of the ossicular chain may explain these findings. Dysplasia of the second arch, which develops into the lower part of the ossicular chain, may contribute to ossicular malformation in CAA and CAS. Accurate radiographic measurement of malformed ossicles may be useful for reconstructive surgery of CAA and CAS using the patient's native ossicular chain and for choosing an appropriate place for active middle ear implants.

The Vibrant Soundbridge© (VSB) active middle-ear implant provides an effective treatment for mild-to-severe sensorineural hearing loss in the case of normal middle ear anatomy and mixed hearing loss in middle ear malformation. The VSB floating mass transducer (FMT), with proper couplers, can be installed on various structures of the ossicular chain, e.g., the short and long process of the incus, the stapes head, and the stapes footplate. A long process (LP) coupler is most commonly used for FMT attachment to the long process of the incus with intact ossicular chain, while CliP and Bell couplers are two standardized and reliable methods for FMT attachment to the stapes head with missing incus and malleus. However, the difference and relationship of the vibration properties among these three FMT couplers remain unclear. In the present study, the stapes footplate velocity responses of the LP, CliP, and Bell couplers have been investigated in eight fresh temporal bones (TBs) to evaluate the vibration properties of these three couplers. Normal and reconstructed middle ear transfer functions (METFs) were determined from laser Doppler vibrometer (LDV) measurements. A mastoidectomy and a posterior tympanotomy were performed to expose the ossicular chain. The METFs of the normal middle ear and middle ear with LP-FMT-coupler were compared under acoustic stimulation, thus the mass effect of the FMT with LP coupler was evaluated. Additional comparisons were made between the stapes footplate vibrations of the LP-FMT-coupler (with the intact ossicular chain at the long process of the incus), CliP-FMT-coupler and Bell-FMT-coupler on the stapes head (after incus and malleus removed) under active electromechanical stimulation. After the installation of CliP-FMT-coupler and Bell-FMT-coupler to the middle ear, the average velocity amplitude of the stapes footplate, comparing to the LP-FMT-coupler, was about 15 dB higher between 1 and 6 kHz, and 10 dB lower at about 0.5 kHz. Quantitatively, there was no significant difference between the CliP-FMT-coupler and Bell-FMT-coupler. According to our study, installation of CliP-FMT-coupler or Bell-FMT-coupler on the stapes head provides considerable improvement of the middle ear mechanical and functional responses, comparing with the LP-FMT-coupler in the temporal bone experiments. Moreover, the installation of the Bell-FMT-coupler to the stapes head produces essentially the same footplate velocity responses in comparison to the CliP-FMT-coupler.

Bimetallic nickel cobalt sulfide (Ni 1.5 Co 1.5 S 4 ) is successfully fabricated by an ultrafast and cost-effective microwave assisted hydrothermal method. When used as electrode material for lithium-ion batteries, Ni 1.5 Co 1.5 S 4 exhibits the remarkable electrochemical performance in terms of superior cycling stability, excellent specific capacity and good rate capability. A high specific capacity of 443 mA h g −1 after 200 charge-discharge cycles at a current density of 0.5 A g −1 is achieved. Even at 1 A g −1 , the sample still delivers a discharge capacity of 386 mA h g −1 with a high columbic efficiency of 99.6% after 500 cycles.

We describe our recent progress on a novel method to prepare Ti 1.4 V 0.6 Ni hydrogen storage alloy covered with nanostructured Co 3 O 4 by utilizing zelolitic imidazolate framework 67 (ZIF-67) as the template. Ti 1.4 V 0.6 Ni@C@Co 3 O 4 composite is prepared through a dopamine self-polymerization and a facile precipitation reaction with the subsequent thermal treatment. This specific composite structure combines the high conductivity of carbon together with the promising catalytic property of nanostructured Co 3 O 4 , therefore the enhanced electrochemical activity and stability are realized. As a result, Ti 1.4 V 0.6 Ni@C@Co 3 O 4 composite electrode possesses a capacity conservation rate of 56.1% after 300 charging/discharging cycles, remarkably larger than that of Ti 1.4 V 0.6 Ni (25.3%). Moreover, a study of the kinetics demonstrates that nanostructured Co 3 O 4 coating accelerates the charge-transfer reaction of the electrode. These results prove that coating with carbon and nanostructured Co 3 O 4 is a potential method for enhancing electrochemical hydrogen storage properties of hydrogen storage alloys.

The ammonia-low hydroxide coprecipitation process has successfully synthesized Ni0.6Co0.2Mn0.2(OH)2 precursor by replacing ammonia with NH4+ and lowering the pH of the salt solution with acid. NH4+ and H+ increase the diffusion range of the salt solution and both react with OH−, which would reduce the nucleation rate and increase the complexation under low ammonia concentration conditions. The optimal pH of coprecipitation is determined from the theoretical calculation on the competitive relationship between complexation (Me(NH3)n2+) and precipitation (OH−) using chemical equilibrium and solubility product constant. And compared with other different complexing agents (e.g., NH4+, H+, and NH3), the material obtained with both NH4+ and H+ has the optimized particle morphology, size, composition, and element distribution. The resulting LiNi0.6Co0.2Mn0.2O2 cathode material exhibits superior electrochemical properties, when compared to a commercial sample, with a high initial discharge capacity (176.6 mAh g−1), cycling stability (91.9% retention for 100 cycles), and rate capability (115.7 mAh g−1 at 3C). Moreover, it also demonstrates excellent electrochemical performance in lithium-ion full batteries matched with commercial graphite or Si/C anodes. Ammonia-low coprecipitation synthesis would greatly reduce the treatment cost of production wastewater, improve the working environment of operators, and protect the natural ecological environment of the earth.

In this study, GO-MOFs derived rGO coating/sandwiching Co3O4 composites (denoted as rGO/Co3O4) are fabricated by employing a temperate coprecipitation method with ZIF-67 rhombic dodecahedron as a template and GO as a substrate. In these composites, nanoporous and rGO coating (denoted as rGO@Co3O4)/sandwiching (denoted as Co3O4-rGO-Co3O4) structures are designed, which endow the composites with strong potential application as electrode materials for lithium-ion batteries (LIBs) and supercapacitors (SCs). Here, the as-prepared rGO@Co3O4 and Co3O4-rGO-Co3O4 composites not only exhibit outstanding lithium storage performances with high initial discharge specific capacities (1451 and 1344 mA h g−1 at a current density of 100 mA g−1), excellent cycling stabilities (above 96% and 95% retention after 100 cycles) and admirable rate capabilities (328 and 450 mA h g−1 at a current density of 2000 mA g−1), but also display superior pseudocapacitive properties with high specific capacitance (546 F g−1), remarkable rate capability and brilliant cycling stability (90% of initial capacitance retention at 5 A g−1 after 10000 cycles). The remarkable porous architecture and electrical conductivity enables GO-MOFs derived transition metal oxide composites to be promising electrode materials for next generation LIBs and SCs.

One-dimensional (1D) porous FeS2@C nanowires as a high cathode material for lithium-ion batteries (LIBs) are synthesized on a large-scale from an organic-inorganic hybrid nanowire precursor. The FeS2@C nanowires not only provide a continuous and fast electron transport pathway, favorable diffusion kinetics, but also provide the protection buffer the volume expansion and effectively prevent the polysulfides from dissolving in the electrolyte during cycling. Attributing to the synergistic advantages of both 1D porous nanostructure and the encapsulation of thin amorphous carbon layers, the FeS2@C nanowires exhibit remarkable lithium storage performance with a high specific capacity of 889 mA h g−1 at 0.1 A g−1 and 521 mA h g−1 at 10 A g−1. Moreover, a discharge energy density of 1225 Wh kg−1 is obtained at 2 A g−1 and remains as high as 637 Wh kg−1 after 1000 cycles, which is even higher than the LiCoO2 cathode. The results demonstrate that the potential for applications in LIBs with high power density and long cycling life.

Copper sulfide nanoflower/reduced graphene oxide (CuS/rGO) composite is synthesized using Cu(NO 3 ) 2 , thiourea (Tu) and graphene oxide (GO) powers as the precursor by an ultrafast microwave-assisted hydrothermal method. The electrochemical performances of CuS/rGO composite as anode material of Lithium ion batteries (LIBs) are studied both in ether-based (LiTFSI in DOL/DME) and carbonate-based electrolytes (LiPF 6 in EC/DMC). The results reveal that CuS/rGO composite exhibits excellent electrochemical Li-storage properties. The reversible capacity of 422 mA h g −1 and 390 mA h g −1 at a current density of 100 mA g −1 after 70 cycles is obtained in both electrolytes, respectively. Even after 200 charge-discharge cycles at 500 mA g −1 in ether-based electrolyte, the composite delivers a good discharge capacity of 390 mA h g −1 with high capacity retention ratio of 96.7%. The good electrochemical performances of CuS/rGO can be attributed to the synergistic effect of the CuS nanoflower and rGO. Briefly, the introduction of rGO can improve the electronic conductivity of the composite, effectively immobilize the CuS and inhibit the dissolution of the polysulfide intermediates generated during the charge-discharge process.

A novel cerium-lead redox flow battery (rfb) employing ce(iv)/ce(iii) and pb(ii)/pb redox couples in the supporting electrolyte of methanesulfonic acid (msa) is developed and preliminarily investigated. the rfb requires no additional catalyst and uses kinetically favorable reactions between low-cost reactants, and provides a desirable discharge voltage of approximately 1.7 v, with high average coulombic efficiency (ce) of 92% and energy efficiency (ee) of 86% over 800 cycles at 298 k. stable cycling with an acceptable performance is achieved for a board operating temperature range of 253 k-313 k. the excellent performance obtained from the preliminary study suggests that the cerium-lead rfb promises to be applicable to large-scale energy storage for electricity grids. (c) 2015 elsevier b.v. all rights reserved.

La0.6Ce0.4Ni3.45Co0.75Mn0.7Al0.1 hydrogen storage alloy has been prepared and its electro-chemical characteristics and gas hydrogen absorption/desorption properties have been investigated at different temperatures. X-ray diffraction results indicated that the alloy consists of a single phase with CaCu5-type structure. It is found that the investigated alloy shows good cycle performance and high-rate discharge ability, which display its promising use in the high-power type Ni-MN battery. The exchange current density and the diffusion coefficient of hydrogen in the bulky electrode increase with increasing temperature, indicating that increasing temperature is beneficial to charge-transfer reaction and hydrogen diffusion. However, the maximum discharge capacity, the charge retention and the cycling stability degrade with the increase of the temperature. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.