There is an increasingly urgent need of lightweight components in aerospace industry, among which aluminum (Al) alloys have been the optimal materials of choice for aircraft structural parts since ...being used in the Junkers F.13 aircraft in the 1920s. Compared to other metal materials, Al alloys have a lower density, and the use of Al alloys reduces the total weight of the aircraft and improves fuel efficiency and load capacity. Meanwhile, the strength and hardness of Al alloys with alloying and heat treatment can be significantly enhanced for uses in high loads and vibration environments. Furthermore, in the harsh aerospace environment, aircraft may receive various climatic conditions and chemical corrosion. Due to good corrosion and fatigue resistance, Al alloys demonstrate excellent performance under these conditions, ensuring the long–term service life of aircraft. In addition, Al alloys have good recyclability, and they can be recycled to reduce resource consumption and environmental load, in line with the principle of sustainable development. In recent years, although composites have been widely used in aerospace, high–strength Al alloys are still in an indispensable position. Therefore, this article reviews the progress and applications of Al alloys commonly used in aerospace. The common strengthening methods and advanced manufacturing and processing technologies of Al alloy are also discussed, which can provide references for the development of advanced high–performance aviation Al alloys in the future.
The functions of Sertoli cells in spermatogenesis have attracted much more attention recently. Normal spermatogenesis depends on Sertoli cells, mainly due to their influence on nutrient supply, ...maintenance of cell junctions, and support for germ cells' mitosis and meiosis. Accumulating evidence in the past decade has highlighted the dominant functions of the MAPK, AMPK, and TGF-β/Smad signaling pathways during spermatogenesis. Among these pathways, the MAPK signaling pathway regulates dynamics of tight junctions and adherens junctions, proliferation and meiosis of germ cells, proliferation and lactate production of Sertoli cells; the AMPK and the TGF-β/Smad signaling pathways both affect dynamics of tight junctions and adherens junctions, as well as the proliferation of Sertoli cells. The AMPK signaling pathway also regulates lactate supply. These signaling pathways combine to form a complex regulatory network for spermatogenesis. In testicular tumors or infertile patients, the activities of these signaling pathways in Sertoli cells are abnormal. Clarifying the mechanisms of signaling pathways in Sertoli cells on spermatogenesis provides new insights into the physiological functions of Sertoli cells in male reproduction, and also serves as a pre-requisite to identify potential therapeutic targets in abnormal spermatogenesis including testicular tumor and male infertility.
Integrating photonics and electronics into a single chip with a variety of capabilities is attracting particular interest for achieving high‐density and high‐speed multifunctional smart ...optoelectronic systems. However, it remains challenging to realize this goal because of the difficulty of merging various areas of science and technology. A smart responsive integrated photoelectric organic modulator is created here, which can not only possess emission wavelength switching tunability in response to light and heat but also show good optical amplification performance and field‐effect transistor properties. By applying external stimuli on the resulting smart responsive system based on the judicious combination of conjugated polymers and photochromic molecules can enable efficient and reversible tuning of light emission between red and yellow via a controllable way through effective manipulation of energy transfer channels induced by optical and thermal stimuli. More importantly, stimuli‐responsive emission, optical amplification, and efficient carrier transport can be simultaneously integrated in a single device with optical and electrical performance comparable to those of stand‐alone devices. The results suggest an effective way to create smart integration of photonic and electronic elements in a chip with multifunctional optoelectronic characteristics for various applications such as integrated photonics, electronics, optoelectronics, and smart sensing.
A smart responsive integrated photoelectric organic modulator is created, which can not only possess emission wavelength switching tunability in response to light or heat but also show good optical amplification performance and field‐effect transistor properties.
As an essential path toward the elucidation of the reaction mechanism, the capture of the catalytically active phase and its evolution has been the primary goal of mechanistic studies. Here, the ...physicochemical properties on In2O3 (111) and Pt/In2O3 (111) thin film model catalysts were tracked in CO2 hydrogenation atmosphere under various pressures and temperatures by ambient pressure X‐ray photoelectron spectroscopy (APXPS). The redox behaviours of surface Pt and In2O3, the formation and interconversion of reaction intermediates, and the structural dynamics at the topmost surface, as a consequence of the outward diffusion of InOx species, nucleation of surface Pt nanostructures and the formation of PtInOx species, were captured and analyzed. The reconstruction at the Pt/In2O3 (111) interface was also observed by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and scanning electron microscopy (SEM) analysis. In‐situ spectroscopic and structural analysis on a well‐defined metal/metal‐oxide interface offers a powerful means to probe the mechanistic details of the heterogeneous processes.
Mechanistic details of the metal/metal‐oxide interface for heterogeneous processes: The surface physicochemical properties of In2O3 (111) and Pt/In2O3 (111) were investigated using ambient pressure X‐ray photoelectron spectroscopy in the atmosphere of CO2 hydrogenation reaction, including redox behaviors of surface Pt and In2O3, the formation and interconversion of reaction intermediates. Dynamic interfacial reconstruction was observed and demonstrated by SEM and 3D topological elemental mappings using ToF‐SIMS.
Display omitted
•A comprehensive review of the application of solid waste in building insulation materials.•Solid waste mainly comes from municipal, industry and agriculture.•Life cycle cost, annual ...power consumption and pollutant gas emissions were calculated.•Based on the decision analysis method, the most promising building insulation material was determined.
The effective application of solid waste in building insulation materials is of great significance to the global economic and social development, because energy shortages and environmental pollution are two global problems that need to be solved urgently. However, unfortunately, there are few, or no systematic studies on this aspect. In order to fill this gap, solid waste was divided into municipal solid waste, industrial solid waste and agricultural solid waste according to the source. The bulk density, thermal conductivity, water absorption and compressive strength of three types of solid waste recycled building insulation materials were systematically evaluated. The relationships between bulk density and thermal conductivity and compressive strength were given, respectively. For solid waste recycled building insulation materials with poor thermal performance and flame retardancy, corresponding improvement suggestions were put forward. Taking a city as an example, the life cycle cost (LCC), energy consumption and gas emissions were discussed in detail. Based on the decision analysis method, the most promising building insulation material was selected. Finally, in view of the shortcomings of the existing study, the future study direction in this field was proposed.
Information processing with optoelectronic devices provides an alternative way to efficiently process hybrid optical and electronic signals. Ferroelectric field‐effect transistors (FeFETs) can ...effectively respond to external optical and electrical stimuli by modulating their polarization states. Here, a 2D FeFET is demonstrated by the epitaxial growth of high‐quality 2D bismuth layered oxyselenide (Bi2O2Se) films on PMN‐PT(001) ferroelectric single‐crystal substrates. Upon switching the polarization direction of PMN‐PT, the authors realize in situ, reversible, and nonvolatile manipulation of the resistance of Bi2O2Se thin film (≈877%). The device simultaneously exhibits a polarization‐dependent photoresponse through visible light (λ = 405 nm) and infrared light (IR, λ = 980 nm) illumination. Combining optical stimuli with ferroelectric gating, it is demonstrated that the devices not only show nonvolatile memory and optoelectronic responses, but also show coincidence detection of visible and IR light. This work holds great potential in constructing new multiresponse and multifunction 2D‐FeFETs.
2D ferroelectric field‐effect transistors devices are fabricated by epitaxial growth of Bi2O2Se on Pb(Mg1/3Nb2/3)O3‐PbTiO3. The devices exhibit ferroelectric polarization‐dependent photoresponse upon visible light (λ = 405 nm) and infrared light (IR, λ = 980 nm) illumination. Combining optical stimuli with ferroelectric gating, the devices show not only nonvolatile memory and optoelectronic response, but also coincidence detection of visible and infrared light.
Microbial fuel cells (MFCs) have attracted considerable interest due to their potential in renewable electrical power generation using the broad diversity of biomass and organic substrates. However, ...the difficulties in achieving high power densities and commercially affordable electrode materials have limited their industrial applications to date. Carbon materials, which can exhibit a wide range of different morphologies and structures, usually possess physiological activity to interact with microorganisms and are therefore fast‐emerging electrode materials. As the anode, carbon materials can significantly promote interfacial microbial colonization and accelerate the formation of extracellular biofilms, which eventually promotes the electrical power density by providing a conductive microenvironment for extracellular electron transfer. As the cathode, carbon‐based materials can function as catalysts for the oxygen‐reduction reaction, showing satisfying activities and efficiencies nowadays even reaching the performance of Pt catalysts. Here, first, recent advancements on the design of carbon materials for anodes in MFCs are summarized, and the influence of structure and surface functionalization of different types of carbon materials on microorganism immobilization and electrochemical performance is elucidated. Then, synthetic strategies and structures of typical carbon‐based cathodes in MFCs are briefly presented. Furthermore, future applications of carbon‐electrode‐based MFC devices in the energy, environmental, and biological fields are discussed, and the emerging challenges in transferring them from laboratory to industrial scale are described.
Carbon‐based electrodes with different morphologies and structures are widely used in microbial fuel cells from conductive supports (anode) to active catalysts (cathode). Recent advancements in the design of carbon materials for anodes (conductivity, biofilm formation, interaction) and cathodes (catalytic activity) are discussed separately. The future perspectives and emerging challenges of this area are also highlighted.
Historical geographic data play an important supporting role in the study of long-term geographic studies, such as climate change, urban expansion and land-use and land-cover change. These data vary ...in source, format and accuracy and are widely found in historical documents, old maps, produced vector data, aerial photographs, old photographs, etc. The complex nature of data makes it difficult for researchers to organize, store and manage in a unified manner. Thus, GIS practitioners and social scientists will collectively face the challenge of integrating historical data into spatial databases. Herein, we introduced the concept of a multi-level spatial grid, selecting Shanghai as the study area, to construct the Shanghai historical geographic database and give the conceptual model and processing method. The experiment was performed using the China Historical Geographic Information System (CHGIS), which showed the historical evolution of Shanghai more conveniently. Meanwhile, we simulated one million rows of historical geographic data in Shanghai and compared the retrieval efficiency of the encoding method with the latitude–longitude and geometric object indexing methods, which demonstrated that our method was very effective. This research is important for the construction of a historical urban database, which can better preserve historical resources and promote urban culture with information science and technology.
Abstract
After the first quasiperiodic eruption (QPE; GSN 069) was reported in 2019, four other sources have been identified as a QPE or a candidate. However, the physics behind QPEs is still ...unclear, although several models have been proposed. Pan et al. proposed an instability model for an accretion disk with magnetically driven outflows in the first QPE of GSN 069, which is able to reproduce both the light curve and the evolution of the spectra fairly well. In this work, we extend this model to all QPEs. We improve the calculations of the spectrum of the disk by introducing a hardening factor, which is caused by a deviation of opacity from a blackbody. We find that the light curves and evolution of the spectra of the four QPEs and candidates can all be well reproduced by our model calculations.
The vascular response to pro-atherosclerotic factors is a multifactorial process involving endothelial cells (ECs), macrophages (MACs), and smooth muscle cells (SMCs), although the mechanism by which ...these cell types communicate with each other in response to environmental cues is yet to be understood. Here, we show that miR-155, which is significantly expressed and secreted in Krüppel-like factor 5 (KLF5)-overexpressing vascular smooth muscle cells (VSMCs), is a potent regulator of endothelium barrier function through regulating endothelial targeting tight junction protein expression. VSMCs-derived exosomes mediate the transfer of KLF5-induced miR-155 from SMCs to ECs, which, in turn, destroys tight junctions and the integrity of endothelial barriers, leading to an increased endothelial permeability and enhanced atherosclerotic progression. Moreover, overexpression of miR-155 in ECs inhibits endothelial cell proliferation/migration and re-endothelialization in vitro and in vivo and thus increases vascular endothelial permeability. Blockage of the exosome-mediated transfer of miR-155 between these two cells may serve as a therapeutic target for atherosclerosis.
PDF
