Electronic Noses: From Gas-Sensitive Components and Practical Applications to Data Processing.

Artificial olfaction, also known as an electronic nose, is a gas identification device that replicates the human olfactory organ. This system integrates sensor arrays to detect gases, data acquisition for signal processing, and data analysis for precise identification, enabling it to assess gases both qualitatively and quantitatively in complex settings. This article provides a brief overview of the research progress in electronic nose technology, which is divided into three main elements, focusing on gas-sensitive materials, electronic nose applications, and data analysis methods.

Perforating and ophthalmic artery variants from the anterior cerebral artery: Two case reports.

Background: The diagnosis and therapy during surgery depend largely on a full account of anatomic characteristics. Apart from regular structures, the common, less common or even uncommon anatomic variations are critical for procedural planning. This is especially true during craniocerebral microsurgery, where small vascular variations can affect the final surgical results and patient prognosis.

Selective Photocatalytic Reduction of CO to CO Mediated by Silver Single Atoms Anchored on Tubular Carbon Nitride.

Artificial photosynthesis is a promising strategy for converting carbon dioxide (CO ) and water (H O) into fuels and value-added chemical products. However, photocatalysts usually suffered from low activity and product selectivity due to the sluggish dynamic transfer of photoexcited charge carriers. Herein, we describe anchoring of Ag single atoms on hollow porous polygonal C N nanotubes (PCN) to form the photocatalyst Ag @PCN with Ag-N coordination for CO photoreduction using H O as the reductant.

Zr-Al co-doped SrTiO with suppressed charge recombination for efficient photocatalytic overall water splitting.

Zr-Al co-doped SrTiO with reduced Ti concentration demonstrates more than 2 times enhancement compared with Al-doped SrTiO in photocatalytic overall water splitting. Systematic studies reveal that the co-doping of Zr can reduce the substitution of Ti by Al and effectively suppress the formation of charge carrier recombination centers (Ti).

Boron Dopant Induced Electron-Rich Bismuth for Electrochemical CO Reduction with High Solar Energy Conversion Efficiency.

Electrochemical CO reduction to formate offers a mild and feasible pathway for the utilization of CO , and bismuth is a promising metal for its unique hydrogen evolution reaction inhibition. Reported works of Bi-based electrodes generally exhibit high selectivity while suffering from relatively narrow working potential range. From the perspective of electronic modification engineering, B-doped Bi is prepared by a facile chemical reduction method in this work.

Effect of ball milling process on the mechanical and thermal properties of the nanodiamond/2024Al composites.

In this study, 5 wt.% nanodiamond (ND) reinforced 2024Al matrix composites (ND/2024Al) were fabricated with various ball milling processes. The microstructure, compressive yield strength (σ) and coefficient of thermal expansion (CTE) of ND/2024Al composites were investigated.

Effect of pre-strain on microstructure and micro-yield properties of Al-Cu-Li alloy.

In this study, Al-Cu-Li alloys were pre-strained to various plastic strains before ageing. The T1 (AlCuLi) precipitates and dislocation density in various pre-strained Al-Cu-Li alloys were analyzed with transmission electron microscopy (TEM) and X-ray diffraction (XRD) technology respectively. The micro-yield strength (Micro-YS) of tested alloys was measured and the strengthening mechanism was discussed.

Designing Carbonized Loofah Sponge Architectures with Plasmonic Cu Nanoparticles Encapsulated in Graphitic Layers for Highly Efficient Solar Vapor Generation.

Solar vapor generation represents a promising approach to alleviate water shortage for producing fresh water from undrinkable water resources. Although Cu-based plasmonics have attracted tremendous interest due to efficient light-to-heat conversion, their application faces great challenges in the oxidation resistance of Cu and low evaporation rate. Herein, a hybrid of three-dimensional carbonized loofah sponges and graphene layers encapsulated Cu nanoparticles is successfully synthesized via a facile pyrolysis method.

Effect of external stress on the microstructure and mechanical properties of creep-aged Al-Cu-Li-Ag alloy.

The effects of external stress on the precipitation of T precipitates and mechanical properties of creep-aged Al-Cu-Li-Ag alloys are investigated. Promotion mechanisms of external stress to the precipitation of T precipitates are discussed. It is found that external stress significantly promotes the precipitation and improves the distribution of the T precipitates in the creep-aged alloys.

Efficient photocatalytic conversion of CH into ethanol with O over nitrogen vacancy-rich carbon nitride at room temperature.

A record ethanol production rate of 281.6 μmol g-1 h-1 for the photocatalytic conversion of methane over nitrogen vacancy-rich carbon nitride at room temperature was achieved. Systematic studies demonstrate that the CH4 was activated by the highly reactive ˙OH radicals generated, via H2O2, from the photo-reduction of O2 with H2O.

Cl modification for effective promotion of photoelectrochemical water oxidation over BiVO.

Postsynthetic treatment is an attractive method to enhance photoelectrochemical water splitting. The facile Cl modification approach developed in this work remarkably promotes the photocurrent density of BiVO up to 2.7 mA cm by facilitating carrier transfer in addition to a charge carrier separation efficiency enhancement.

The pollution levels, variation characteristics, sources and implications of atmospheric carbonyls in a typical rural area of North China Plain during winter.

Atmospheric carbonyls were measured at a typical rural area of the North China Plain (NCP) from November 13 to December 24, 2017 to investigate the pollution characteristics, sources and environmental implications. Fifteen carbonyls were detected, and formaldehyde, acetaldehyde and acetone accounted for about 81% at most. The concentration of the total carbonyls in heavily polluted days was twice more than that in clean days.

Synthesis of Surface-Oxygen-Vacancy-Rich (GaN)(ZnO) Particles with Enhanced Visible-Light Photodegradation Performance.

In this study, zinc-gallium oxynitrides with a Zn:Ga mole ratio of 1:1 [(GaN)(ZnO)] were synthesized from a Zn/Ga/CO layered double hydroxide (LDH) precursor. The microstructure and photoactivity of the (GaN)(ZnO) particles were tuned by adjusting the nitridation conditions of the LDH. It is revealed that the quantity of the LDH, or, equivalently, the partial pressure of the water during nitridation, plays a pivotal role in the defect structure of the obtained oxynitrides.

Copper nanoparticles selectively encapsulated in an ultrathin carbon cage loaded on SrTiO as stable photocatalysts for visible-light H evolution via water splitting.

One-nanometre-thick carbon cage encapsulated copper nanopaticles on SrTiO3 (STO) synthesized through a facile chemical vapour deposition method showed remarkable stability and performance for both photocatalytic hydrogen evolution and thermocatalytic reduction of 4-nitrophenol. X-ray photoelectron spectroscopy and Raman results demonstrate that the graphene cage effectively protected Cu nanoparticles from being oxidized.

Remarkable Visible-Light Photocatalytic Activity Enhancement over Au/p-type TiO Promoted by Efficient Interfacial Charge Transfer.

Metal-induced photocatalysis has emerged as a promising approach for exploiting visible-light-responsive composite materials for solar energy conversion, which is generally hindered by low photocatalytic efficiency. Herein, for the first time, an Au/p-TiO (p-type TiO) strategy with the hole transfer mechanism is developed, remarkably promoting visible-light photocatalytic performance. An efficient acetone evolution rate (138 μmol·g·h) in the photocatalytic isopropyl alcohol (IPA) degradation under λ = 500 nm light (light intensity, 5.

Fabrication of InGaN Nanowires on Tantalum Substrates by Vapor-Liquid-Solid Chemical Vapor Deposition.

InGaN nanowires (NWs) have drawn great attentions for their applications in optoelectronic and energy conversion devices. Compared to conventional substrates, metal substrates can offer InGaN NW devices with better thermal conductivity, electric conductivity, and mechanic flexibility. In this article, InGaN NWs were successfully grown on the surface of a tantalum (Ta) substrate via vapor-liquid-solid chemical vapor deposition (VLS-CVD), as characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), scanning and transmission electron microscope (STEM), and photoluminescence spectroscopy (PL).

Conformal BiVO-Layer/WO-Nanoplate-Array Heterojunction Photoanode Modified with Cobalt Phosphate Cocatalyst for Significantly Enhanced Photoelectrochemical Performances.

Constructing semiconductor heterojunctions via surface/interface engineering is an effective way to enhance the charge carrier separation/transport ability and thus the photoelectrochemical (PEC) properties of a photoelectrode. Herein, we report a conformal BiVO-layer/WO-nanoplate-array heterojunction photoanode modified with cobalt phosphate (Co-Pi) as oxygen evolution cocatalyst (OEC) for significant enhancement in PEC performances. The BiVO/WO nanocomposite is fabricated by coating a thin conformal BiVO layer on the surface of presynthesized WO nanoplate arrays (NPAs) via stepwise spin-coating, and the decoration of Co-Pi OEC is realized by photoassisted electrodeposition method.

Boosting the Photocatalytic Activity of P25 for Carbon Dioxide Reduction by using a Surface-Alkalinized Titanium Carbide MXene as Cocatalyst.

Although they are widely used as cocatalysts in promoting photocatalysis, practical application of noble metals is limited by their high cost and rarity. Development of noble-metal-free cocatalysts is thus highly demanded. Herein titanium carbide (Ti C ) MXene is shown to be a highly efficient noble-metal-free cocatalyst with commercial titania (P25) for photocatalytic CO reduction.

CO tolerance of Pt/FeO catalyst in both thermal catalytic H oxidation and electrochemical CO oxidation: the effect of Pt deficit electron state.

CO poisoning of Pt catalysts is one of the major challenges to the commercialization of proton exchange membrane fuel cells. One promising solution is to develop CO-tolerant Pt-based catalysts. A facilely synthesized Pt/FeO catalyst exhibited outstanding CO tolerance in the oxidation of H and electrochemical CO stripping.

Development of Novel Erythromycin Derivatives with Inhibitory Activity against Proliferation of Tumor Cells.

In our continuing structure-activity relationship study of a new class of erythromycin A (EM-A) derivatives with antiproliferative activity, a new series of de(N-methyl) EM-A dimers jointed by a four-atom linker, -CH2CH = CHCH2-, were prepared and their antiproliferative activity against three human tumor cell lines was evaluated by MTT assay. The most active EM-A dimer, compound 1b, that carrying C6 methoxyl groups was further investigated and showed potent antiproliferative activity in six other human tumor cell lines. Flow cytometry analysis of 1b treated HeLa and MCF-7 cells indicated that the four-atom EM-A dimers induced the SubG1 phase cell cycle arrest and cell apoptosis, in time- and dose-dependent manners.

Nanometals for Solar-to-Chemical Energy Conversion: From Semiconductor-Based Photocatalysis to Plasmon-Mediated Photocatalysis and Photo-Thermocatalysis.

Nanometal materials play very important roles in solar-to-chemical energy conversion due to their unique catalytic and optical characteristics. They have found wide applications from semiconductor photocatalysis to rapidly growing surface plasmon-mediated heterogeneous catalysis. The recent research achievements of nanometals are reviewed here, with regard to applications in semiconductor photocatalysis, plasmonic photocatalysis, and plasmonic photo-thermocatalysis.

High performance Au-Cu alloy for enhanced visible-light water splitting driven by coinage metals.

A Au-Cu alloy strategy is, for the first time, demonstrated to be effective in enhancing visible-light photocatalytic H2 evolution via promoting metal interband transitions. Au3Cu/SrTiO3, in which oxidation of Cu was successfully restrained, showed the highest visible-light H2 evolution activity.