[en] So as to change the conductivity and stationarity of NiO anode materials which was in lithium batteries, the precursors were synthesized through solvothermal measure and NiO/Ni/C composites were prepared by high temperature carbonization. The material composition was analyzed by a method named X-ray diffraction. The surface of the material was characterized through scanning electron microscopy and transmission electron microscopy, and applied to the negative electrode of lithium battery for electrochemical performance test. The results show that the NiO/Ni/C composite with pore structure has excellent performance and cycle stability in electrochemical tests. The NiO/Ni/O electrode still achieved a specific capacity of 743.7 mAh•g⁻¹ according to cycling 100 at 0.36 A•g⁻¹. (paper)

[en] We report a novel rapid microwave synthesis of two-dimensional MoS₂. Morphological and structural characterizations were performed by XRD and SEM, which showed that the obtained MoS₂ was a sheet-like structure with good crystallization. The electrochemical performance illustrated that the MoS₂ electrode prepared with 0.0300 mol Na₂MoO₄ has a higher specific capacitance is 83.4 F g⁻¹ at 0.5 A g⁻¹, and favorable electrochemical durability up to 91.0 %, after 4000 cycles. (paper)

[en] In this paper, ZIF-8/ZIF-67 derived carbon (ZDC) was synthesized by surface modification technology and calculation process subsequently. In order to evaluate the feasibility of ZDC for antibiotic removal, the adsorption experiments were carried out by three typical antibiotics: tetracycline (TC), norfloxacin (NFO) and ofloxacin (OFO). The results showed that the maximum adsorption capacities of TC, NFO and OFO based on ZDC were 543.48, 239.8 and 340 mg/g, respectively. The adsorption capacity of ZDC was better than that of many other similar adsorbents, which is a potential adsorbent for antibiotic removal in the contaminated water. (paper)

[en] Fluid elastic excitation in shell side of heat exchanger was deduced theoretically in this paper. Model foundation was completed by using Pro / Engineer software. The finite element model was constructed and imported into the FLUENT module. The flow field simulation adopted the dynamic mesh model, RNG k-ε model and no-slip boundary conditions. Analysing different positions vibration of tube bundles by selecting three regions in shell side of heat exchanger. The results show that heat exchanger tube bundles at the inlet of the shell side are more likely to be failure due to fluid induced vibration. (paper)

[en] Objective: To analyze the effect of the new conformal index (nCI) and the conventional conformal index (CI) on the treament planning quality of lung stereotopic radiotherapy (SBRT). Methods: A total of 19 peripheral lung cancer patients, treated with SBRT in Fujian Medical University Union Hospital from 2014 to 2017, were analyzed retrospectively. Each patient was planned twice yielding identical CI and nCI. The prescription to 95% of planning target volume (PTV) was 48 Gy in four fractions, and renormalization was performed when needed for nineteen nCI plans. The Wilcoxon signed-rank test was used to examine the dosimetric index. Results: The dose conformity plots indicate that nCI does not only reflect the dose to the organ at risk outside tumor, but also represents the dose distribution in the PTV. In addition, nCI was stricter with treatment planning qualities when the dose around PTV was closer to the prescribed dose. The value of target coverage (TC), the ratio of out-of-target volumes receiving 105% prescribed dose to the target volume (R_105%), the ratio of volume covered by 50% isodose line to the target volume (R₅₀%), and the ipsilateral lung V₂₀ were 98.70%, 0.56, 5.53, 15.59% in the CI plans, vs. 90%, 0, 4.99, 14.42% in the corresponding nCI plans, respectively. All index were significantly lower in the nCI group (Z = -3.823, -3.180, -3.823, -3.783, respectively, P < 0.05). The ratio of the maximum dose to the 2 cm external margin from the PTV (D_{2 cm}) to the maximum dose to the PTV were 63.70% and 64.07% respectively in the two groups, and the differences were not statistially significant (P > 0.05). The conformity values denoted a clinically favorable value as 1 between D_95% and D_99% of nCI plans, yet were not applicable to CI plans. Conclusions: It is more clinically relavant to evaluate lung SBRT plans using nCI, TC and other indicators collectively than using CI alone. (authors)

[en] Highlights: • Proposing two different destination selection preferences in a metapopulation model. • A Markov chain method is utilized to discuss the probabilities of information spreading. • Increasing the mobility has little effect on information spreading. • Prefer to move to higher information prevalence neighbors promotes information spreading. Many recent studies have shown that the characteristics of human activities such as mobility and network structure have significant impacts on information spreading. This paper proposes a destination selection strategy in a metapopulation model, there are two different destination selection preferences about the strategy. The Markov chain method is utilized to discuss the information spreading dynamics. In the experimental results of Erdös-Rényi (ER) network structure, when the movement preference is determined, the range of information propagation will increase slightly with the increase of mobility probability. Mobility has little impact on the information outbreak threshold. When exploring the impact of destination selection strategy on the scope of information dissemination, compared with moving to the neighbor nodes with lower information prevalence, individuals who prefer to move to the neighbors with higher information prevalence will bring more extensive information coverage. Similar phenomena are revealed on the Barabási-Albert (BA) model.

[en] The uniformly nanosized NiO were prepared via chemical co-precipitation method. Electrochemical characterization of the NiO nanoparticles showed the initial specific discharge capacity reaches 900 mAh/g at 0.1 A/g and 500 mAh/g at 2 A/g, which reveals that the as-synthesized material could be potential candidate of anode material for LIBS. (paper)

[en] Polypyrrole (PPy) has high electrochemical activity and low cost, so it has great application prospects in wearable supercapacitors. Herein, we have successfully prepared polypyrrole/reduced graphene oxide (PPy/rGO) nanocomposite cotton fabric (NCF) by chemical polymerization, which exhibits splendid electrochemical performance compared with the individual. The addition of rGO can block the deformation of PPy caused by the expansion and contraction. The as-prepared PPy-0.5/rGO NCF electrode exhibits the brilliant specific capacitance (9300 mF cm⁻² at 1 mA cm⁻²) and the capacitance retention with 94.47% after 10 000 cycles. At the same time, the superior capacitance stability under different bending conditions and reuse capability have been achieved. All-solid-state supercapacitor has high energy density of 167 μWh cm⁻² with a power density of 1.20 mW cm⁻². Therefore, the PPy-0.5/rGO NCF electrode has a broad application prospect in high-performance flexible supercapacitor fabric electrode. (paper)

[en] Nitrogen-enriched graphene coupled with nickel hydroxide nanosheets (Ni(OH)₂/NG) hydrogel is successfully synthesized through a facile one-pot hydrothermal method. Comprehensive investigations reveal that the nitrogen atoms are successfully inserted into graphene and that the nickel hydroxide nanosheets (∼30–50 nm) are anchored on NG homogeneously. With the enhanced electroactivity caused by nitrogen doping and the synergy effect from Ni(OH)₂ nanosheets and NG, the Ni(OH)₂/NG hydrogel electrode displays much better electrochemical properties than two individual electrodes. It features a specific capacitance as high as 896 F g⁻¹ at 0.5 A g⁻¹ and even 504 F g⁻¹ at 12 A g⁻¹ showing a high rate capability (56.3% retention with 24 times higher current density). An asymmetric supercapacitor device on the basic of Ni(OH)₂/NG hydrogel and activated carbon (AC) was assembled and delivered a high energy density of 28.7 W h kg⁻¹ at the power energy density of 0.36 kW kg⁻¹. Such results indicate that the Ni(OH)₂/NG hydrogel could be considered as a promising candidate for electrochemical supercapacitors.

[en] Heteroatom-doped carbon materials with a high specific area, a well-defined porous structure is important to high-performance supercapacitors (SCs). Here, S and N co-doped three-dimensional porous graphene aerogel (NS-3DPGHs) have been synthesized in a facile and efficient self-assembly process with thiourea acting as the reducing and doping agent solution. Operating as a SC electrode, fabricated co-doping graphene, i.e. the sample of NS-3DPGH-150 exhibits the highest specific capacitance of 412.9 F g⁻¹ under 0.5 A g⁻¹ and prominent cycle stabilization with 96.4% capacitance retention in the back of 10 000 cycles. Furthermore, based on NS-3DPGH-150, the symmetrical supercapacitor as-prepared in 6 M KOH displays a superior energy density of 12.9 Wh kg⁻¹ under the power density of 249 W kg⁻¹. Hence, NS-3DPGHs could be considered as an excellent candidate for SCs. (paper)