Carbon‐encapsulated Li3VO4 is synthesized by a facile environmentally benign solid‐state method with organic metallic precursor VO(C5H7O2)2 being chosen as both V and carbon sources yielding a core–shell nanostructure with lithium introduced in the subsequent annealing process. The Li3VO4 encapsulated with carbon presents exceeding rate capability (a reversible capability of 450, 340, 169, and 106 mAh g−1 at 0.1 C, 10 C, 50 C, and 80 C, respectively) and long cyclic performance (80% capacity retention after 2000 cycles at 10 C) as an anode in lithium‐ion batteries. The superior performance is derived from the structural features of the carbon‐encapsulated Li3VO4 composite with oxygen vacancies in Li3VO4, which increase surface energy and could possibly serve as a nucleation center, thus facilitating phase transitions. The in situ generated carbon shell not only facilitates electron transport, but also suppresses Li3VO4 particle growth during the calcination process. The encouraging results demonstrate the significant potential of carbon encapsulated Li3VO4 for high power batteries. In addition, the simple generic synthesis method is applicable to the fabrication of a variety of electrode materials for batteries and supercapacitors with unique core–shell structure with mesoporous carbon shell.

Mesocrystal MnO cubes consisted of nanocrystals (~16 nm) with percolated nanopores (~10.5 nm) and a porosity of 45% were synthesized through polyvinyl alcohol (PVA) assisted hydrothermal growth and homoepitaxial aggregation. The resulting MnO crystal makes up of appreciable amount of Mn 3+ , ~11.8%, ascribed to incomplete reduction during the hydrothermal growth, and the presence of such an appreciable amount of Mn 3+ is thought to lead to the enhancement of Li ion diffusion coefficient from 6.96×10 -14 cm 2 /s to 3.33×10 -13 cm 2 /s. Carbon coating derived from polyvinyl alcohol and homoepitaxial connection of nanocrystals provides excellent charge and mass transfer pathways. Such mesocrystal MnO cubes enhanced the contact of electrolyte and electrode materials, at the same time the active nanocrystals with trivalent manganese ions and cationic vacancies would promote the conversion reaction for lithium-ion insertion and extraction, leading to a high capacity of 637 mAh/g at 100 mA/g in a relatively smaller voltage range of 0.05-2.50V, as compared with a voltage window of 0.01-3V used by other research groups. The high voltage (4V) Li-ion capacitor, a full cell with mesocrystal MnO cubes as anode and activated carbon as cathode, demonstrated excellent cycling performance with the degradation rate of 0.002% per cycle, and the achieved maximum energy in full capacitor reached 227 Wh kg -1 that calculated on the total weight of the active materials in both electrodes. IntroductionEnergy storage devices owned both high energy and power density have a huge market potential for the rapid development of portable electronic apparatus, electric vehicles and smart stationary grid as well as for renewable energy [1,2] . It is the holy-grail in the field of energy storage technology to search and develop high capacity electrode materials with wide operating voltage window and rapid charge/discharge kinetics [3][4][5] . Combining the high energy density of Li-ion batteries and high power density of supercapacitors provides an alternate approach to satisfy the demand for both high energy and power density devices [6] . Batteries offer high energy density but suffer from relatively low power density, while supercapacitors possess high power density with limited energy density [3,7] . Li-ion batteries store chemical potential and convert it to electricity through electrode-electrolyte interface redox reactions accompanied with solid state charge and mass diffusion through electrodes, whereas electric double layer capacitors (also known as supercapacitors) rely on the formation of electric double layers at the interface between electrode and electrolyte without solid state mass transport through electrode [7] . Li-ion capacitors integrate the merits of high specific energy of Li-ion batteries and high power density of electric double layer capacitors (EDLCs) [6,8] . Besides, with a given capacity, the wide operating voltage window of Li-ion electrolytes endows high energy density, which is directly proportional to the operating ...

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A new ZIF-8 membrane architecture with high performance supported on vertically aligned ZnO nanorods was successfully prepared. The vertically aligned, single crystal ZnO nanorods were grown seamlessly from porous ceramic support to form an intermediate support layer for the ZIF-8 membrane. They provide multiple anchorages for the ZIF-8 membrane that are both strong and flexible. The nanorods were activated to induce a uniform nucleation of ZIF nuclei on their surface to initiate and guide the growth of a defect-free ZIF-8 membrane. Single gas permeations and binary separations carried out to investigate the transport properties of these new membrane architectures confirmed that the ZIF-8 membranes were free of defects and stable at a higher temperature (473 K).

The investigation of community structure in networks has aroused great interest in multiple disciplines. One of the challenges is to find local communities from a starting vertex in a network without global information about the entire network. Many existing methods tend to be accurate depending on a priori assumptions of network properties and predefined parameters. In this paper, we introduce a new quality function of local community and present a fast local expansion algorithm for uncovering communities in large-scale networks. The proposed algorithm can detect multiresolution community from a source vertex or communities covering the whole network. Experimental results show that the proposed algorithm is efficient and well-behaved in both real-world and synthetic networks.

A new Mo-doped LiV3O8 nanorod-assembled nanosheet was prepared by a simple hydrothermal method and subsequent calcination. Its unique structure demonstrates a maximum discharge capacity of 269 mAh g−1 at 300 mA g−1 within 4.0-2.0 V, and excellent rate and cycle performance for Li-ion batteries.

Li3VO4 has been demonstrated to be a promising anode material for lithium-ion batteries with a low, safe voltage and large capacity. However, its poor electronic conductivity hinders its practical application particularly at a high rate. This work reports that Li3VO4 coated with carbon was synthesized by a one-pot, two-step method with F127 ((PEO)100-(PPO)65-(PEO)100) as both template and carbon source, yielding a microcuboid structure. The resulting Li3VO4/C cuboid shows a stable capacity of 415 mAh g(-1) at 0.5 C and excellent capacity stability at high rates (e.g., 92% capacity retention after 1000 cycles at 10 C = 4 A g(-1)). The lithiation/delithiation process of Li3VO4/C was studied by ex situ X-ray diffraction and Raman spectroscopy, which confirmed that Li3VO4/C underwent a reversible intercalation reaction during discharge/charge processes. The excellent electrochemical performance is attributed largely to the unique microhollow structure. The voids inside hollow structure can not only provide more space to accommodate volume change during discharge/charge processes but also allow the lithium ions insertion and extraction from both outside and inside the hollow structure with a much larger surface area or more reaction sites and shorten the lithium ions diffusion distance, which leads to smaller overpotential and faster reaction kinetics. Carbon derived from F127 through pyrolysis coats Li3VO4 conformably and thus offers good electrical conduction. The results in this work provide convincing evidence that the significant potential of hollow-cuboid Li3VO4/C for high-power batteries.

Cervical cancer is the third most common gynecologic cancer in the United States. The presence and possible involvement of several cytokines have been studied in cervical cancer; however, very little data, if any, are available on whether cervical tumors are responsive to stimulation by the macrophage colony-stimulating factor-1 (CSF-1). Given the involvement of c-fms and its ligand CSF-1 in gynecologic cancers, such as that of the uterus and the ovaries, we have examined the expression of c-fms and CSF-1 in cervical tumor (n = 17) and normal cervix (n = 8) samples. The data show that c-fms and its ligand are significantly higher in cervical carcinomas compared with normal samples. Immunohistochemistry not only showed that tumor cells expressed significantly higher levels of c-fms but also c-fms levels were markedly higher in tumor cells than tumor-associated stromal cells. Blocking c-fms activity in cervical cancer cells, which express CSF-1 and c-fms, resulted in increased apoptosis and decreased motility compared with control, suggesting that CSF-1/c-fms signaling may be involved in enhanced survival and possibly invasion by cervical cancer cells via an autocrine mechanism. Combined, the data show for the first time the induction of CSF-1 and c-fms in cervical carcinomas and suggest that c-fms activation may play a role in cervical carcinogenesis. Additionally, our data suggest that transforming growth factor-B1 may be a factor in inducing the expression of c-fms in cervical cancer cells. The data suggest that c-fms may be a valuable therapeutic target in cervical cancer. [Cancer Res 2007;67(5):1918-26]