Plasmon coupling nanorice trimer for ultrahigh enhancement of hyper-Raman scattering.

A new tactic that using Ag nanorice trimer as surface-enhanced hyper Raman scattering substrate is proposed for realizing maximum signal enhancement. In this paper, we numerically simulate and theoretically analyze the optical properties of the nanorice trimer consisting of two short nanorices and a long nanorice. The Ag nanorice trimer can excite Fano resonance at optical frequencies based on the strong interaction between the bright and the dark mode.

Community engagement in public health: a bibliometric mapping of global research.

Background: Community engagement (CE) has been regarded as a critical element of successful health programs to achieve "the health for all" goals. Numerous studies have shown that it plays a significant role in reducing inequalities, improving social justice, enhancing benefits, and sharing responsibility towards public health. Despite this, the extant literature of community engagement in public health (CEPH) has topic-focused boundaries and is scattered across disciplinary.

[Formation Mechanism and Source Analysis of Two Heavy Pollution Periods in Winter in a Central Plains City].

To reveal the process and cause of air pollution in winter in Zhengzhou, Zhengfangji Station was selected as the sampling point to discuss the concentration of air pollutants and the characteristics of meteorological parameters in December 2019, in Zhengzhou. The concentration changes in PM water-soluble ions, elements, and carbon components in different pollution stages were compared, and air quality model simulation results were used to analyze emissions from pollution sources and regional transmission during sampling of the PM mass concentration at the sampling point. The results showed that there was a slight difference in the process of formation and dissipation of the first and second heavy pollution occurrences, showing the characteristics of "slow accumulation, slow removal" and "slow accumulation, fast removal", respectively.

Two-dimensional GaO monolayer with tunable band gap and high hole mobility.

By means of density functional theory and unbiased structure search computations, we systematically investigated the stability and electronic properties of a new Ga2O2 monolayer. The phonon spectra and ab initio molecular dynamics simulations show that the Ga2O2 monolayer is dynamically and thermally stable. Moreover, it also shows superior open-air stability.

Phylogenetic Analysis of HIV-1 Genomes Based on the Position-Weighted K-mers Method.

HIV-1 viruses, which are predominant in the family of HIV viruses, have strong pathogenicity and infectivity. They can evolve into many different variants in a very short time. In this study, we propose a new and effective alignment-free method for the phylogenetic analysis of HIV-1 viruses using complete genome sequences.

Rheological Properties of SBS/CRP Composite Modified Asphalt under Different Aging Treatments.

The objective of this study is to evaluate the rheological properties of SBS/CRP composite modified asphalt under different aging conditions in alpine cold regions. In this study, the styrene-butadiene-styrene (SBS) block copolymer, crumb rubber powder (CRP), softeners and various additives were used to prepare the SBS/CRP composite modified asphalt. The 4.

Highly Compressible Polymer Composite Foams with Thermal Heating-Boosted Electromagnetic Wave Absorption Abilities.

Polymer composite foams are desirable materials for electromagnetic (EM) energy attenuation. However, a number of challenges limit improvement in the EM energy attenuation properties of foams. In this study, a simple microcellular injection molding method was used to fabricate highly compressible thermoplastic urethane (TPU)/carbon nanotube (CNTs) composite foams, which also had increased conductivity with an increase in CNT content.

Z-scheme TiO@TiC/CdZnS nanocomposites with efficient photocatalytic performance via one-step hydrothermal route.

Photocatalytic degradation of pollutants has been proved to be an effective strategy for wastewater treatment. Herein, TiO nanoparticles were synthesized on a TiC matrix by in situ growth, forming Z-scheme TiO@TiC/CdZnS (TO/CZS) multilevel structured nanocomposites via one-step hydrothermal route. The effects of hydrothermal temperature and CdZnS content on microstructure and properties of composites were assessed.

Magnetic critical behavior of the van der Waals FeGeTe crystal with near room temperature ferromagnetism.

The van der Waals ferromagnet FeGeTe has a Curie temperature T of about 270 K, which is tunable through controlling the Fe deficiency content and can even reach above room temperature. To achieve insights into its ferromagnetic exchange that gives the high T, the critical behavior has been investigated by measuring the magnetization in FeGeTe crystal around the ferromagnetic ordering temperature. The analysis of the measured magnetization by using various techniques harmonically reached to a set of reliable critical exponents with T = 273.

Galvanic Replacement Reaction Involving Core-Shell Magnetic Chains and Orientation-Tunable Microwave Absorption Properties.

Electromagnetic (EM) wave absorption materials have attracted considerable attention because of EM wave pollution caused by the proliferation of electronic communication devices. One-dimentional (1D) structural magnetic metals have potential as EM absorption materials. However, fabricating 1D core-shell bimetallic magnetic species is a significant challenge.

Evaluation of linkage efficiency between manufacturing industry and logistics industry considering the output of unexpected pollutants.

Applied a non-radical non-oriented Slack Based Measure (SBM) model of Data Envelopment Analysis (DEA) to measure the linkage efficiency between the two sectors from 2009 to 2016. The paper analyzes the current situation of manufacturing and logistics efficiency, presents a way to improve the linkage efficiency of manufacturing and logistics industry, and using Tobit regression to analyze the environmental factors that affect the linkage efficiency. The results show that: Totality, the two industries in the three northeast provinces show a steady development trend in the period from 2009 to 2016, but the development of the two industries in northeast China is still insufficient.

An ANP-fuzzy evaluation model of food quality safety supervision based on China's data.

A government acts as the main supervisor of food quality and safety. How to quantify and improve the performance and efficiency of government supervision, respectively, is an urgent problem. This study constructs a food safety supervision performance index and utilizes an analytic network process-fuzzy comprehensive evaluation model to precisely quantify the performance of government supervision.

An Effective Design Strategy for the Sandwich Structure of PVDF/GNP-Ni-CNT Composites with Remarkable Electromagnetic Interference Shielding Effectiveness.

It is well-known that attractive electromagnetic interference (EMI) shielding performance depends on functional (e.g., electrical and magnetic) fillers and structural designs.

A two-thresholds policy for a Filippov model in combating influenza.

This work designs a two-thresholds policy for a Filippov model in combating influenza, so as to estimate when and whether to take control strategies, including the media coverage, antiviral treatment of infected individuals and vaccination of susceptible population. By introducing two tolerance thresholds [Formula: see text] and [Formula: see text] of susceptible and infected individuals, the two-thresholds policy is designed as: a vaccination program is implemented when the number of susceptible individuals is above [Formula: see text]; an antiviral treatment strategy is taken and the mass media begins to report information about influenza when the infection number is larger than [Formula: see text]; no control strategies are required in other cases. Furthermore, the global dynamics of the model are analyzed by varying these two thresholds, including the existence and dynamics of sliding mode, and the existence and global stability of equilibrium.

Game Analysis on the Evolution of Decision-Making of Vaccine Manufacturing Enterprises under the Government Regulation Model.

The harm caused by defective vaccines to human health and social stability is immeasurable. Aiming at the government's supervision of the vaccine market, an evolutionary game model is constructed to analyze the quality of supervision and the key factors in the dynamic interaction between government departments and vaccine manufacturers under different supervision modes in the vaccine manufacturing process. The results show that: (1) Severe punishment by government regulatory authorities, and increased costs of rectification after investigation and handling of involuntary behaviors of vaccine enterprises can effectively prevent involuntary behaviors of vaccine enterprises.

The effect of solid content on the rheological properties and microstructures of a Li-ion battery cathode slurry.

The development of new materials and the understanding of the microstructure formation of electrodes have become increasingly important for improving Li-ion battery performance. In this study, we investigate the effect of solid content on the rheological properties of and the microstructures in the cathode slurry prepared from Ni-rich materials. With long-chain structures, PVDF molecules can change their configurations when they come into contact with the solid particles in slurries, and their bridging function can change with the solid content in the slurry.

Prevalence and pollution characteristics of antibiotic resistant genes in one high anthropogenically-impacted river.

The objectives of this study were to comprehensively investigate the occurrence, distribution, and mobility of antibiotic resistant genes (ARGs) in the biofilm, water, and sediment from a section of the Weihe-river, in the northern Henan province, China. The abundances of nine ARGs belonging to four commonly used antibiotic classes (tetracyclines, sulfonamides, fluoroquinolones, and multidrug) and class 1 integron-integrase gene (intI1) were quantified. Sulfonamides gene (sulI) accounted for the highest percentage of detected ARGs in most sampling sites, including in water, biofilm, and sediment.

The impact of financial contagion on real economy-An empirical research based on combination of complex network technology and spatial econometrics model.

This study presents financial network indicators that can be applied to inspect the financial contagion on real economy, as well as the spatial spillover and industry aggregation effects. We propose to design both a directed and undirected networks of financial sectors of top 20 countries in GDP based on symbolized transfer entropy and Pearson correlation coefficients. We examine the effect and usefulness of the network indicators by newly using them instead of the original Dow Jones financial sector as explanatory variables to construct the higher-order information spatial econometric models.

Orientation and Microstructure Evolution of Al-AlCu Regular Eutectic Lamellar Bifurcating in an Abruptly Changing Velocity under Directional Solidification.

In an abruptly changing velocity under directional solidification, microstructures and the growth orientation of Al-AlCu eutectic lamellar were characterized. The change in solidification rate led to an interfacial instability, which results in a bifurcation of the eutectic lamella into new, refined lamellae. The growth orientation of the eutectic AlCu phase was also only in its (001) direction and more strongly oriented to the heat flow direction.

Influence of the Mineral Powder Content on the Asphalt Aging Resistance in High-Altitude Areas Based on Indoor Ultraviolet Light Tests.

Intense ultraviolet irradiation is an important environmental factor affecting the service performance of asphalt mixtures in high-altitude areas, and the asphalt mortar is the main factor affecting the durability of asphalt mixtures. It is of great theoretical significance and engineering value to study the performance of the asphalt mortar at medium and low temperatures under ultraviolet irradiation. Therefore, this paper focuses on the evolution of the effect of the filler content on the rheological properties of different asphalt materials at low and medium temperatures under quantitative UV irradiation.

Flexible PEBAX/graphene electromagnetic shielding composite films with a negative pressure effect of resistance for pressure sensors applications.

In the current work, we fabricated flexible poly(ether--amide) (PEBAX)/graphene composite films by a combination of facile melt blending and compression molding technique. The graphene content significantly affects the mechanical properties, electrical conductivity and electromagnetic interference (EMI) shielding performance. An electrically conductive percolation threshold of 1.

Enhanced Electromagnetic Wave-Absorbing Performance of Magnetic Nanoparticles-Anchored 2D TiCT MXene.

Two-dimensional TiCT MXene-based hybrids-anchored magnetic metal nanoparticles show a huge potential application as effective wave absorbers due to the synergistic electromagnetic (EM) loss effect. In this work, uniform and size-controllable nickel, cobalt, or nickel-cobalt alloy nanoparticles were in situ grown on the surface of MXene via a facile and moderate co-solvothermal method for the first time. As an example, a nickel nanoparticles-anchored MXene (Ni@MXene) hybrid was homodispersed into dielectric polyvinylidene fluoride to develop its EM wave-absorbing capacity to a great extent.

Asymmetrically Spatial Effects of Urban Scale and Agglomeration on Haze Pollution in China.

Rapid urbanization in China not only promotes the rapid expansion of urban population and economic agglomeration, but also causes the aggravation of haze pollution. In order to better clarify the asymmetric and nonlinear effects of urban scale and agglomeration on haze pollution, this paper quantitatively evaluates the spatial spillover effects of population size and economic agglomeration on haze pollution in 342 Chinese cities from 2001 to 2016 by using exploratory spatial data analysis (ESDA) and spatial econometric model. The results show the following: (1) During the research period, the distribution of urban scale, agglomeration, and haze pollution in China presented complex asymmetrical features, with the former two presenting a "core-periphery" distribution mode, while the latter having a tendency to spread around.

Inverted Hydration Layers on Bio-Magnesium Surfaces in the Initial Degradation Stage and their Influence on Adsorption of Amino Acid Analogues: The Metadynamics Simulations.

Deeply exploring the interaction of biomolecules with magnesium in solution is essential to understand the formation of complex bio-magnesium interfaces accompanied with corrosion products. Using the accelerated metadynamics simulations, we have investigated the interactions of amino acid analogues on clean and hydroxylated Mg(0001) surfaces by identifying their free energy barriers and adsorption sites. We find that there are two hydration layers stacked on the clean Mg(0001) surfaces and the hydroxylated Mg(0001) surfaces, which mainly determine the free energy barriers and adsorbed configurations.

Ultrathin, Porous and Oxygen Vacancies-Enriched Ag/WO Heterostructures for Electrocatalytic Hydrogen Evolution.

Exploring advanced electrocatalysts for electrocatalytic hydrogen evolution is highly desired but remains a challenge due to the lack of an efficient preparation method and reasonable structural design. Herein, we deliberately designed novel Ag/WO heterostructures through a supercritical CO -assisted exfoliation-oxidation route and the subsequent loading of Ag nanoparticles. The ultrathin and oxygen vacancies-enriched WO nanosheets are ideal substrates for loading Ag nanoparticles, which can largely increase the active site density and improve electron transport.