Insights into Nano-and Micro-Structured Scaffolds for Advanced Electrochemical Energy Storage

Adopting a nano-and micro-structuring approach to fully unleashing the genuine potential of electrode active material benefits in-depth understandings and research progress toward higher energy density electrochemical energy stor-age devices at all technology readiness levels.Due to various challenging issues,especially limited stability,nano-and micro-structured(NMS)electrodes undergo fast electrochemical performance degradation.The emerging NMS scaffold design is a pivotal aspect of many electrodes as it endows them with both robustness and electrochemical performance enhancement,even though it only occupies comple-mentary and facilitating components for the main mechanism.However,extensive efforts are urgently needed toward optimizing the stereoscopic geometrical design of NMS scaffolds to minimize the volume ratio and maximize their functionality to fulfill the ever-increasing dependency and desire for energy power source supplies.This review will aim at highlighting these NMS scaffold design strategies,summariz-ing their corresponding strengths and challenges,and thereby outlining the potential solutions to resolve these challenges,design principles,and key perspectives for future research in this field.Therefore,this review will be one of the earliest reviews from this viewpoint.

Role of in-situ formed nano-and micro-fibrils in micro-fatigue resistance of bio-polyethylene

In response to the need for the reduction of micro-debris generation in artificial humanjoints for extending the service life, a novel polymer process technology, SCORIM (shear con-trolled orientation injection moulding), was employed to manufacture a polyethylene compositereinforced by in-situ formed nano- and micro-fibrils. Tribological performance of a blend of ultrahigh molecular weight polyethylene (UHMWPE) and high density polyethylene (HDPE) was evalu-ated on a pin-on-disc wear machine. Results indicate a significant improvement in micro fatiguewear resistance compared with those moulded by a conventional injection moulding technology.Scanning electron microscopy reveals that a micro-fibril structure forms as an in-situ fibre rein-forced composite using SCORIM while an aggregated structure occurs in specimens moulded byconventional technology. DSC analysis shows the occurrence of a second phase: shish kebabmicrostructure using SCORIM. Transmission electron microscopy reveals the transformation ofmicrostructure from randomly orientated lamella in the specimens moulded by conventional injec-tion moulding into nano-fibril shish kebab microstructure, which results in a significant reduction inthe possibility of the initiation and development of micro-cracks parallel to the contact surfacesusing SCORIM. Consequently, the formation of nano-fibril shish kebab and micro-fibril microstruc-ture by using the novel SCORIM technology results in a significant reduction in micro-fatigue whenusing the surface normal to the direction of the orientated molecular fibril microstructure as a con-tact surface.

Variations in nano-and pico-eukaryotic phytoplankton assemblages in the Qinhuangdao green-tide area

Qinhuangdao coastal waters have been frequently hitting by nano-and pico-eukaryotic phytoplankton(NPEP)blooms and green tides(macroalgal blooms)in the recent decade.However,understanding about the impacts of environmental factors and the green tides on the NPEP assemblages in this area is limited.In this study,the composition of NPEP assemblages and their variations were analyzed via amplicon sequence variants(ASVs)assay based on amplicon high-throughput sequencing data with the 18S V4 region as a targeted gene in the Qinhuangdao green-tide area during the green tide.Consequently,average NPEP effective sequences and ASVs of 178000 and 200 were obtained from each sample,respectively.Although there were 25 classes,110 genera,and 97 species of NPEP were identified and annotated,the proportions of annotated ASVs at genus and species levels were only 44.7%and 17.8%,respectively.The NPEP communities had a seasonal succession from diatom-dominated to dinoflagellate-dominated.During the three investigations,Skeletonema,Karlodinium,and Gonyaulax were the most dominant genera in May,August,and September,respectively.Species diversity and the abundance of NPEP communities could be increased by a high content of dissolved organic nitrogen(DON)and dissolved organic phosphorus(DOP)but inhibited by low dissolved inorganic phosphorus content.The outbreak of green tides could alter the composition and content of nutrients and accelerate the succession of the NPEP communities from diatom-dominated to dinoflagellate-dominated under the background of a seasonal increase in seawater temperature.These results preliminarily revealed the impacts of the recurrent occurrences of green tides on the NPEP assemblages in the Qinhuangdao green-tide area exhibiting high DON content and dissolved inorganic nitrogen/phosphorus ratio.

Elastic modulus of claystone evaluated by nano-/micro-indentation tests and meso-compression tests

Toarcian claystone such as that of the Callovo-Oxfordian is a qualified multiphase material. The claystone samples tested in this study are composed of four main mineral phases: silicates(clay minerals, quartz,feldspars, micas)(z86%), sulphides(pyrite)(z3%), carbonates(calcite, dolomite)(z10%) and organic kerogen(z1%). Three sets of measurements of the modulus of deformability were compared as determined in(i) nanoindentation tests with a constant indentation depth of 2 mm,(ii) micro-indentation tests with a constant indentation depth of 20 mm, and(iii) meso-compression tests with a constant displacement of 200 mm. These three experimental methods have already been validated in earlier studies. The main objective of this study is to demonstrate the influence of the scaling effect on the modulus of deformability of the material. Different frequency distributions of the modulus of deformability were obtained at the different sample scales:(i) in nano-indentation tests, the distribution was spread between 15 GPa and 90 GPa and contained one peak at34 GPa and another at 51 GPa;(ii) in the micro-indentation tests, the distribution was spread between 25 GPa and 60 GPa and displayed peaks at 26 GPa and 37 GPa; and(iii) in the meso-compression tests, a narrow frequency distribution was obtained, ranging from 25 GPa to 50 GPa and with a maximum at around 35 GPa.

A study on nano－ and microdiatoms in the intertidal zones of Zhongshan Station，Antarctica

The present paper deals with the composition and distribution of nano-and microdiatoms in sands and grits covered by ice and snow in the intertidal zones of the Zhongshan Station in Larsemann Hills (69°21'～69°25'S, 76°00'～76°25'E ), East Antarctica. The samples were collected from seven sand-grit flat stations in January 1989 and February 1990. The highest cell density of nano-and microdiatoms occurred at Station B. The cell concentration was 0. 8×103～3651×103 cells per gram sand in January 1989 and 4. 5×103～2618×103 cells Per gram in February 1990 respectively.The nano-and microdiatoms in the intertidal zones were small in cell size and high in abundance. The dominant species was Navicula glaciei.