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In order to solve the problem of capacity reduction of Schiff base monomer in lithium-ion batteries due to the dissolution of active substances, the Schiff base polymer(PI) with C=N bond was prepared by one-step condensation method using p-benzaldehyde and p-phenylenediamine as raw materials. Poly(Schiff base)/carbon nanotubes(PI/CNTs) composites with high conductivity were prepared by doping carbon nanotubes(CNTs). The composition, structure, micro morphology and electrochemical properties of the prepared materials were analyzed by using FT-IR, SEM, XRD, TG, XPS and electrochemical workstation. The results indicate that the PI/CNT material with 5%CNTs(mass fraction) is a three-dimensional frame structure, and shows excellent electrochemical performance. The first specific capacity of PI/CNT-3 material is 209.9 mAh·g-1. After 200 cycles, the cycle retention rate is 60.5%. When the rate of charge and discharge is 0.1 C, 0.2 C, 0.5 C, 1 C and 0.1 C, the specific capacity of PI/CNT-3 electrode materials is 182.4, 150.8, 129.8, 101.3 mAh·g-1 and 156.4 mAh·g-1 respectively, which has good cycle stability and rate performance.

Purpose – Many experts suggest that the human being explore marine resources and marine new energy sources to alleviate the shortage of land resources and the ecological degradation. However, island coastal zones are considered to be fragile ecosystems; their geographical location and natural characteristics, their biodiversity and associated ecosystems, and their exposure to diverse land and sea conditions all make them highly vulnerable to environmental changes and human activities. Therefore, it is necessary to achieve the goals of environmental protection and sustainable development on the basis of a comprehensive evaluation and understanding of islands. Design/methodology/approach – Due to the importance of island groups, this paper conducts evaluation studies on them. Using the Delphi, AHP and TOPSIS methods, this study evaluated quantitatively the comprehensive development level and comprehensive development potential of island groups in terms of resources, natural environment, economy and society. Innovatively using them as two subsystems, the present study combined the coupling coordination model and the obstacle factor calculation method. Findings – The prospective index of comprehensive development was applied to the Changdao Island Group in Yantai, Shandong Province as an example, and the final evaluation revealed that the comprehensive development prospect of this island group had an upward trend from 2010 to 2017. Future efforts should be made to improve its economic and social conditions and economic development status, apart from promoting its comprehensive development by improving human resources management, increasing the GDP growth rate, and improving fresh water and electricity supply. Originality/value – This study takes the integrated development level of the island and the integrated development potential of the island as two subsystems, and the innovative application of the coupling coordination degree model is used to calculate the integrated development index of the island to understand the development status of the island area. On the basis of this model, the obstacle factor identification method is designed to identify the main obstacle factors, and on the basis of evaluation and identification, specific measures to ensure the sustainable development of the island area are effectively proposed.

The interphase structure and Li-ion transport across the interface are essential for high-performance composite solid electrolytes (CPEs). Tailoring the interface between rigid inorganic solid electrolyte fillers and the polymer electrolyte matrix is a promising way. A Li-ion conductive filler such as garnet Li7La3Zr2O12 (LLZO) is proposed for the high performance of CPEs, which suffered from an unavoidable insulating contamination layer and incomplete contact with the polymer matrix. In this study, a wet chemical method was applied for converting the insulation layer on the LLZO surface to LiF with the formation of oxygen vacancies by NH4F solution etching at moderate temperature. The equally dispersed in situ formed LiF in CPEs improves the electrochemical stability. Removal of resistive barriers accompanied by firm contact with the polymer matrix induced by bonding between PEO chains and oxygen vacancies forms a CPE with homogeneous fast Li-ion transport. Owing to these advantageous properties, the ionic conductivity of CPEs with etched LLZO increases from 6.45 × 10−4 S cm−1 to 1.28 × 10−3 S cm−1 at 60 °C, and the electrochemical stable window is extended. An all-solid-state battery with etched powder exhibits extraordinary cycle stability at 2C with an initial discharge capacity of 136 mA h g−1, and capacity retention remains at 90.4% after 300 cycles. [ABSTRACT FROM AUTHOR]

Objective To investigate the value of the clinical application of multislice spiral CT in the measurement of orbital volume. Methods 12 cases of congenital microphthalmia or ocular dysplasia, 4 cases of traumatic eyeball atrophy in children, 15 cases retinoblastoma enucleation, and 64 cases of orbital blowout fracture were plain scanned by CT Measuring software, and the orbital volumes of both side of sick and healthy eyes were measured. Results The volumes of 23 cases of congenital microphthalmia or ocular dysplasia, traumatic eyeball atrophy in children or retinoblastoma enucleation were less than the healthy eyes. The volumes of eyes suffered from orbital blowout fracture were greater than the healthy eyes. Conclusion The technology can evaluate the degree of development of children eyes and estimate the influence of the therapy by the orbital implants. Meanwhile, it can measure the volume of orbital blowout fracture and predict the enophthalmos situation. It is significantly helpful to the therapeutic planning and the assessment in pre-and post-operative. [ABSTRACT FROM AUTHOR]

Optimizing the electrode/electrolyte interface structure is the key to realizing high-voltage Li-metal batteries (LMBs). Herein, a functional electrolyte is introduced to synergetically regulate the interface layer structures on the high-voltage cathode and the Li-metal anode. Saccharin sodium (NaSH) as a multifunctional electrolyte additive is employed in fluorinated solvent-based electrolyte (FBE) for robust interphase layer construction. On the one hand, combining the results of ex-situ techniques and in-situ electrochemical dissipative quartz crystal microbalance (EQCM-D) technique, it can be seen that the solid electrolyte interface (SEI) layer constructed by NaSH-coupled fluoroethylene carbonate (FEC) on Li-metal anode significantly inhibits the growth of lithium dendrites and improves the cyclic stability of the anode. On the other hand, the experimental results also confirm that the cathode-electrolyte interface (CEI) layer induced by NaSH-coupled FEC effectively protects the active materials of LiCoO 2 and improves their structural stability under high-voltage cycling, thus avoiding the material rupture. Moreover, theoretical calculation results show that the addition of NaSH alters the desolvation behavior of Li + and enhances the transport kinetics of Li + at the electrode/electrolyte interface. In this contribution, the LiCoO 2 ǁLi full cell containing FBE+NaSH results in a high capacity retention of 80% after 530 cycles with a coulombic efficiency of 99.8%., (© 2024 Wiley-VCH GmbH.)

Objective: To evaluate the usefulness of nested PCR method in the diagnosis of imported malaria., Methods: A total of 210 blood smears and blood samples on filter paper were taken from persons returned from highly malaria endemic countries. The results of both nested PCR and microscopy for 210 samples were compared., Results: Among the 210 persons, 43 were hospitalized due to malaria, and positive by nested PCR test Among the rest 157 people at high risk of getting malaria, 3 were found plasmodium-positive by microscope (1.91%), and 5 were positive by nested PCR (3.18%). In four samples with discrepancy between the two methods, 1 was microscopy positive and PCR negative, and 3 were microscopy negative and PCR positive. Positive and negative coincidence rate between the two tests was 66.7% and 98.1%, respectively. The coincidence between the two methods was 97.5%., Conclusion: Nested PCR is useful for monitoring, identification and diagnosis of imported malaria.

The primary study of Ginkgo leaf such as crude drug macroscopic and powder characteristics were carried out, and the flavonoids content in the leaf of Ginkgo in different areas of Gansu province was determined by HPLC, in order to provide scientific references for the exploitation of Ginkgo in Gansu province.

Objective: The present study was designed to examine the visual acuity (VA) and contrast sensitivity function (CSF) under three refractive correction methods, the visual performance and vision quality under different correction methods were compared and analyzed., Methods: Twenty three college students with myopia (41 eyes, myopia range: -1.25 D approximately 9.25 D; astigmatism < 0.50 D) were enrolled and fully corrected by three different methods: 1) spectacles with resin lens material (SP); 2) soft contact lens (SCL); 3) rigid gas-permeable lens (RGP). The distant and near LogMar VA and CSF were examined. To avoid the subjective bias, the correction procedure was randomly selected and the VA chart and CSF chart used had the same pattern but different letters' organization or directions., Results: The best corrected distant VA was significantly higher in RGP wearing eyes than those in the Soft-CL and SP wearing eyes (P < 0.01 and P < 0.05, respectively). No statistically significant difference was detected between the SP and SCL wearing eyes. There was no significant difference in the near VA among these three conditions, although the near VA in RGP group was slightly better than that in the SCL condition. There was no significant difference in CSF value at low spatial frequencies (1.5 cpd and 3 cpd) among these three conditions. However, at middle and high spatial frequencies (6 cpd, 12 cpd and 18 cpd), the RGP curve was the highest and followed by the SCL and SP curves., Conclusion: RGP correction offers the best visual acuity quality for myopia subjects. The CSF assessment can be used as an indirect method to evaluate the quality of corrected retinal image.