An aqueous rechargeable battery system is assembled by using metallic zinc and Na(0.95)MnO2 as the negative and positive electrodes, respectively. It is cheap and environmentally friendly, and its energy density is 78 Wh kg(-1). Its cycling performance is very good with only 8% capacity loss after 1000 cycles at 4 C between 1 and 2 V.

A composite membrane based on electrospun poly(vinylidene fl uoride) (PVDF) and lithium polyvinyl alcohol oxalate borate (LiPVAOB) exhibiting high safety (self-extinguishing) and good mechanical property is prepared. The ionic conductivity of the as-prepared gel polymer electrolyte from this composite membrane saturated with 1 mol L −1 LiPF 6 electrolyte at ambient temperature can be up to 0.26 mS cm −1 , higher than that of the corresponding well-used commercial separator (Celgard 2730), 0.21 mS cm −1 . Moreover, the lithium ion transference in the gel polymer electrolyte at room temperature is 0.58, twice as that in the commercial separator (0.27). Furthermore, the absorbed electrolyte solvent is diffi cult to evaporate at elevated temperature. Its electrochemical performance is evaluated by using LiFePO 4 cathode. The obtained results suggest that this gel-type composite membrane shows great possibilities for use in large-capacity lithium ion batteries that require high safety.

A meta-analysis was conducted to determine the influence of gender on overall survival (OS) and cancer-specific survival (CSS) in colorectal cancer patients. Major databases were searched for clinical trials, which compare survival differences between male and female for colorectal cancer patients. A list of these studies and references, published in English and Chinese from 1960 to 2017, was obtained independently by two reviewers from databases such as PubMed, Medline, ScienceDirect, the China National Knowledge Infrastructure (CNKI) and Web of Science. Overall survival and cancer-specific survival were compared using Review Manager 5.3. Females had significantly better OS (hazard ratio [HR] = 0.87; 95% confidence interval [CI] = 0.85-0.89) and CSS (HR = 0.92; 95% CI = 0.89-0.95) than males after meta-analysis. These results suggest that gender seems to be a significant factor influencing survival results among colorectal cancer patients.

A nanocomposite of molybdenum trioxide (a-MoO 3 ) nanobelts coated with polypyrrole has been fabricated by a simple in situ polymerization route. The structure, morphology and electrochemical performance of the nanocomposite were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and electrochemical measurements. It was found that the polypyrrole acted as a conducting matrix and a coating agent, which effectively improves the conductivity of the MoO 3 nanobelts and inhibits the dissolution of molybdenum ions during cycling. The supercapacitor based on the PPy@MoO 3 nanocomposite as the anode, activated carbon as the cathode and 0.5 M K 2 SO 4 aqueous solution as the electrolyte exhibits better rate capability as well as excellent cycling performance compared to the virginal MoO 3 .

Nanoporous selenium was prepared by a simple mechanical method adopting nano-CaCO3 as a template. When used as a cathode, it can exhibit relatively high capacity and good cycling behaviour. These results present great promise for this new cathode material for rechargeable lithium batteries of high energy density.

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Widespread use of fossil fuels has resulted in many environmental problems. There is an urgent need to search for reliable green energy storage technologies. The electrical energy storage systems based on neutral aqueous solutions are attractive candidates compared to the present energy storage systems utilizing flammable and expensive organic electrolytes because of their improved safety, low cost and environmental friendliness. What is more, high-rate performance can be achieved due to the high ionic conductivity of the aqueous electrolytes. However, the lower electrochemical window of water limits the possible high output voltage and high energy density. Recently, many new concepts based on neutral aqueous energy storage chemistries including aqueous rechargeable batteries and supercapacitors have exhibited high power and energy densities, excellent cycling life and high Coulombic efficiency. The present paper reviews the latest advances in these new chemistries based on neutral aqueous electrolytes, and the challenges and outlooks in this field are briefly commented on and discussed.

Using a simple hydrothermal procedure, cobalt oxide (Co3O4) with preferred orientation along (220) planes is in situ prepared and coated on MWCNT. The prepared Co3O4@MWCNT nanocable shows superior electrochemical performance as cathode material for aqueous supercapacitors in 0.5 M KOH solution. Its redox peaks retain the well-defined shapes even when the scan rate increases to 200 mV/s. Its specific capacitance is high, 590 F/g at 15 A/g and 510 F/g even at 100 A/g within the potential range from -0.2 to 0.58 V (vs SCE). There is no capacitance fading after 2000 full cycles. This excellent performance is superior to the pristine and the reported Co3O4, which is ascribed to the unique nanocable structure with orientation.