A New Method to Calculate Electromagnetic Impedance Matching Degree in One-Layer Microwave Absorbers

A delta-function method was proposed to quantitatively evaluate the electromagnetic impedance matching degree. Measured electromagnetic parameters of {\alpha}-Fe/Fe3B/Y2O3 nanocomposites are applied to calculate the matching degree by the method. Compared with reflection loss and quarter-wave principle theory, the method accurately reveals the intrinsic mechanism of microwave transmission and reflection properties. A possible honeycomb structure with promising high-performance microwave absorption according to the method is also proposed.Comment: 13 pages, 3 figure

The content and ratio of type I and III collagen in skin differ with age and injury

The aim of this study is to examine type I and III collagen content and distribution in skin within the contexts of patient age and injury, as well as to elucidate possible mechanisms of hypertrophic scar formation. Normal human skin and hypertrophic scar specimens were obtained from spontaneously aborted fetuses and burn patients of different ages (adolescent group, ≤18 years; adult group, >19 and ≤50 years; elderly group, >50 years). Total collagen content was indirectly determined by quantification of hydroxyproline. Levels of type I and III collagen as well as the ratio of type I/III were determined by immunohistochemistry and image analysis. Results obtained showed that the mean content of type I and III and type I/III ratio in normal skin differed significantly among age groups (P0.05), with the lowest levels of type I, III, and the highest ratio of type I/III observed in the elderly age group. Differences between normal uninjured skin and hypertrophic scar tissue were significant for all investigated parameters within any of the three age groups examined (adolescent, adult, elderly; P<0.05). Content of type I, III collagen and type I/III ratio also exhibited age-dependent differences during recovery in hypertrophic scar specimens. Thus, type III collagen synthesis decreases with age resulting in a skewed type I/III ratio and changes in skin tension, elasticity, and healing. Also, the content of type I, III collagen and type I/III ratio are significantly altered in hypertrophic scar tissue compared to uninjured age-matched controls, resulting in a different structural organization that is also influenced by patient age.Key words: Age group, hypertrophic scar, collagen type I, collagen type III, immunohistochemistry, hydroxyproline

From building to city level dynamic digital Twin: A review from data management perspective

The development of the digital twin (DT) has been focused greatly after the concept was brought from the manufacturing and aerospace areas. In the architectural, engineering, construction and facility management (AEC/FM) sector, DTs are capable of integrating heterogeneous metadata and cutting-edge technologies like artificial intelligence and machine learning to create a dynamic digital environment for various purposes. Although building information modelling (BIM) appears to be a significant contributor to DTs, one of the major limitations for DT development is how to construct and provide a shared data environment for all stakeholders to collaborate throughout the life cycle. Furthermore, as the stakeholders' requirements range of DTs expands from a single building to multiple buildings and regional/city levels, the information and data management gaps (e.g., BIM and GIS data integration) are more challenging and critical. To address these gaps, this paper aims to 1) review the current data management for building and city level DTs from a technical perspective; 2) summarise their major data management issues from building to city levels based on the review; 3) introduce the concept of city-level Common Data Environment (CDE) that addresses the issues identified above, and discuss the possibilities of developing a CDE for a dynamic city-level DT

Effect of Hydrothermal Treatment Temperature on the Properties of Sewage Sludge Derived Solid Fuel

High moisture content along with poor dewaterability are the main challenges for sewage sludge treatment and utilization. In this study, the effect of hydrothermal treatment at various temperature (120-200 ˚C) on the properties of sewage sludge derived solid fuel was investigated in the terms of mechanical dewatering character, drying character, calorific value and heavy metal distribution. Hydrothermal treatment (HT) followed by dewatering process significantly reduced moisture content and improved calorific value of sewage sludge with the optimum condition obtained at 140˚C. No significant alteration of drying characteristic was produced by HT. Heavy metal enrichment in solid particle was found after HT that highlighted the importance of further study regarding heavy metal behavior during combustion. However, it also implied the potential application of HT on sewage sludge for heavy metal removal from wastewater

Real-space mapping of tailored sheet and edge plasmons in graphene nanoresonators

Plasmons in graphene nanoresonators have many potential applications in photonics and optoelectronics, including room-temperature infrared and terahertz photodetectors, sensors, reflect arrays or modulators1, 2, 3, 4, 5, 6, 7. The development of efficient devices will critically depend on precise knowledge and control of the plasmonic modes. Here, we use near-field microscopy8, 9, 10, 11 between λ0 = 10–12 μm to excite and image plasmons in tailored disk and rectangular graphene nanoresonators, and observe a rich variety of coexisting Fabry–Perot modes. Disentangling them by a theoretical analysis allows the identification of sheet and edge plasmons, the latter exhibiting mode volumes as small as 10−8λ03. By measuring the dispersion of the edge plasmons we corroborate their superior confinement compared with sheet plasmons, which among others could be applied for efficient 1D coupling of quantum emitters12. Our understanding of graphene plasmon images is a key to unprecedented in-depth analysis and verification of plasmonic functionalities in future flatland technologies.Peer ReviewedPostprint (author's final draft

Improving solar water-splitting performance of LaTaON_{2} by bulk defect control and interface engineering

Particle-assembled photoanode films for solar water splitting are often subjected to serious electron-hole recombination, thus exhibiting low solar-to-hydrogen efficiency. The construction of efficient particle-assembled photoanode remains a challenge. Here, taking LaTaON_{2} particle-assembled photoanode as a model, bulk defect control and interface engineering were introduced to reduce the electron-hole recombination. As a result, the solar photocurrent of LaTaON_{2} achieves 2.1 mA cm^{-2} at 1.6 V_{RHE} after the modification of CoO_{x}, an order of magnitude greater than the previously-reported value of 0.15 mA cm^{-2}. This dramatic enhancement is mainly ascribed to increased bulk electrical conductivity, and less back reactions on the conductive substrates, as well as facilitated hole transfer to reaction sites. This study may provide guidelines for the construction of highly efficient particle-assembled photoanode films

Plasmon-phonon coupling in large-area graphene dot and antidot arrays

Nanostructured graphene on SiO2 substrates pave the way for enhanced light-matter interactions and explorations of strong plasmon-phonon hybridization in the mid-infrared regime. Unprecedented large-area graphene nanodot and antidot optical arrays are fabricated by nanosphere lithography, with structural control down to the sub-100 nanometer regime. The interaction between graphene plasmon modes and the substrate phonons is experimentally demonstrated and structural control is used to map out the hybridization of plasmons and phonons, showing coupling energies of the order 20 meV. Our findings are further supported by theoretical calculations and numerical simulations.Comment: 7 pages including 6 figures. Supporting information is available upon request to author