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The efficient recovery of fine argentite from polymetallic lead–zinc (Pb–Zn) sulfide ore is challenging. This study investigated nanobubble (NB) adsorption on the argentite surface and its role in enhancing fine argentite flotation using various analytical techniques, including contact angle measurements, adsorption capacity analysis, infrared spectroscopy, zeta potential measurements, turbidity tests, microscopic imaging, scanning electron microscopy, and flotation experiments. Results indicated that the NBs exhibited long-term stability and were adsorbed onto the argentite surface, thereby enhancing surface hydrophobicity, reducing electrostatic repulsion between fine argentite particles, and promoting particle agglomeration. Furthermore, the NBs formed a thin film on the argentite surface, which decreased the adsorption of sodium diethyldithiocarbamate. Microflotation tests confirmed that the introduction of NBs considerably enhanced the recovery of argentite using flotation technology. [ABSTRACT FROM AUTHOR]

Food-grade titanium dioxide (E171) is widely used in food, feed, and pharmaceuticals for its opacifying and coloring properties. This study investigates the formation of reactive oxygen species (ROS) and the aggregation behavior of E171 using the TNO Gastrointestinal (GI) model, which simulates the stomach and small intestine. E171 was characterized using multiple techniques, including electron spin resonance spectroscopy, single-particle inductively coupled plasma–mass spectrometry, transmission electron microscopy, and dynamic light scattering. In an aqueous dispersion (E171-aq), E171 displayed a median particle size of 79 nm, with 73–75% of particles in the nano-size range (<100 nm), and significantly increased ROS production at concentrations of 0.22 and 20 mg/mL. In contrast, when E171 was mixed with yogurt (E171-yog), the particle size increased to 330 nm, with only 20% of nanoparticles, and ROS production was inhibited entirely. After GI digestion, the size of dE171-aq increased to 330 nm, while dE171-yog decreased to 290 nm, with both conditions showing a strongly reduced nanoparticle fraction. ROS formation was inhibited post-digestion in this cell-free environment, likely due to increased particle aggregation and protein corona formation. These findings highlight the innate potential of E171 to induce ROS and the need to consider GI digestion and food matrices in the hazard identification/characterization and risk assessment of E171. [ABSTRACT FROM AUTHOR]

This paper investigates the natural frequency and static analysis of a sandwich annular sector plate with a core exhibiting a negative Poisson’s ratio lattice structure, along with facesheets reinforced with agglomerated graphene nanoplatelets (GPL). Both complete and partial agglomeration states are considered using the Eshelby–Mori–Tanaka micromechanical model. The governing equations of motion are derived using Hamilton’s principle, based on First Shear Deformation (FSD) plate theory and the finite element method. The sandwich plates exhibit an ultra-light characteristic, attributable to the auxetic honeycomb core layer, which possesses a negative Poisson’s ratio, and are further reinforced by two laminated skin layers. The study examines the impact of various parameters, including the geometry of the auxetic honeycomb unit cell, the weight fraction of GPL, and the distribution of GPL on the natural frequency, displacement of the center point of the auxetic honeycomb core, and specific absorbed energy of the sandwich plate. The natural frequency decreases with increasing inclination angle, becoming less sensitive as the ratio λ1, increases. A 57.14% drop occurs for λ1 = 1 when the angle rises from 10∘ to 60∘, while for λ1 = 1.5, 2, and 2.5, the reductions are 25.82%, 13.72%, and 9.23%, respectively. Adding 0.1% GPL without agglomeration raises the natural frequency by 237.85%, enhancing stiffness, but full agglomeration cuts this to 12.47%. The X-pattern has the strongest effect, and the O-pattern the least, with distribution patterns becoming more influential as GPL weight fraction rises. In the partial agglomeration state, performance is optimal when ξ = ζ. For a GPL weight fraction from 0.2% to 1%, displacement drops by 77.94% at ξ = ζ = 0.2 and by 71.68% at ξ = 0.2,ζ = 0.8. [ABSTRACT FROM AUTHOR]

Research Summary: Platforms create value by connecting users to complementors offering goods or services. Complementors compete on platforms but may also benefit each other by drawing demand to the platform, which may then "spillover" from one complementor to another. This tension raises the question: When are relationships between complementors competitive versus complementary? To help address this question, I apply theory on agglomeration‐driven demand spillovers to examine when on‐platform demand spillovers created by peer product launch are larger versus smaller. Studying the Spotify platform, I find spillovers are larger, and peer album release more beneficial to an artist, when the peer stimulates greater demand expansion, platform‐mediated inter‐complementor proximity is higher, and the artist benefits more from consumer learning. Findings extend literature on on‐platform competition and inform complementor strategy. Managerial Summary: On digital platforms, complementor product launch may hurt peer performance by causing substitution or may benefit peer performance by drawing demand to the platform which may then "spillover" from the complementor to a peer. Studying the Spotify platform, I examine when such spillovers are larger versus smaller, shedding light on when peer product launch is beneficial versus detrimental for complementors competing on digital platforms. On Spotify, demand spillovers are larger, and peer album release more beneficial to an artist, when peer album release draws listeners to the platform, Spotify recommendations connect the artist to the peer, and the artist reaches new or unfamiliar listeners. The findings suggest that, on platforms featuring demand spillovers, complementors can take strategic actions to leverage spillovers and improve performance. [ABSTRACT FROM AUTHOR]

Results are presented from measuring optical density in the ultraviolet (UV) and visible ranges of polymer films made of polysulfone (PSF), polymethyl methacrylate (PMMA) and polyvinyl alcohol (PVA) with embedded CNTs, produced by mixing solutions. It is found that adding CNT increases the optical density of polymers, and the efficiency of absorption depends on the choice of polymer. Coefficients of extinction are calculated for CNT in PSF, PMMA, and PVA. The results can be used to develop a way of monitoring the homogeneity of CNT distribution in polymer films. [ABSTRACT FROM AUTHOR]

Triboelectric separation, a solvent-free method, was investigated as a tool for protein enrichment in wheat flour. Gluten–starch model mixtures, flour, and reground flour fractions were evaluated for their separation characteristics (selectivity and efficiency). Mass yield, protein content, particle size distribution, and SEM analysis were used to assess performance. Selectivity and efficiency increased with gluten concentration, peaking at 63% for the 50% gluten mixture, but declined at higher concentrations. The 15% gluten benchmark demonstrated effective protein separation, with protein enrichment occurring in the ground electrode fraction and a corresponding depletion in the positive electrode fraction. In contrast, flour and reground flour fractions exhibited reduced separation efficiency, showing protein depletion in both electrode fractions due to agglomeration. The benchmark achieved the highest separation efficiency (47%), followed by reground flour (41%) and flour (7%). Finer particles in reground flour enhanced chargeability and GE deposition, while larger agglomerates in flour reduced efficiency, leading to material accumulation in the cups. Pre-milling helped detach protein and starch to some extent but also triggered re-agglomeration. Larger particles were influenced more by gravitational forces. These findings highlight the complexity of wheat flour fractionation and the need to optimize particle size and charge distribution to improve protein enrichment through triboelectric separation. [ABSTRACT FROM AUTHOR]

The purpose of this paper is nonlinear vibration analysis of porous piezoelectric nanocomposite microbeams resting on elastic medium exposed to electro-magneto fields. The microbeam is armed by carbon nanotubes (CNTs) in which the Mori–Tanaka theory is applied in order to obtain the structure equivalent material characteristics assuming CNTs agglomeration. The elastic foundation is modeled by two shear, spring and damper elements. The smart nanocomposite structure is subjected to electric fields. The effects of size are supposed by Eringen's nonlocal theory and the surface effects are assumed by Gurtin–Murdoch theory. The structural damping is considered utilizing Kelvin-Voigt theory. In the analytical formulation, normal and shear stresses are considered by Timoshenko–Ehrenfest beam model. The final equations are obtained by Hamilton's principle and energy method considering nonlinear Von-Karman strains. The differential quadrature (DQ) method is utilized in order to calculate the nonlinear frequency in the porous smart nanocomposite microbeam. The influences of various parameters such as nonlocal parameter, viscoelastic medium, microbeam thickness, external voltage, structural damping, magnetic field, different types of porosity parameter, boundary conditions, surface effects and agglomeration of CNTs on the nonlinear frequency of nanocomposite structure are presented. The accuracy of this work is compared by other articles in the literature. Numerical results show that considering agglomeration of CNTs, the nonlinear frequency will be decreased. In addition, the surface effects can enhance the nonlinear frequency significantly. [ABSTRACT FROM AUTHOR]

This paper proposes an optimisation method for fabricating composite materials and functionally graded structures. Using the proposed method, 3D printing of copper (Cu)–polyethylene (PE) composite, Al2O3–ZrO2 ceramic composite and functionally graded CuO foams are utilised. This work aims to advance the capabilities of additive manufacturing by leveraging nature‐inspired approaches to create complex, tailored structures with enhanced performance across various industries. The major objective of the proposed method is to reduce the feed rate and increase the airflow rate and airflow temperature for the heat transfer process. Using the proposed technique in the advanced preparation conditions, Cu–PE composites with unreliable Cu substances are fabricated. The PE binder particle is melting as well as forming thick composites by means of soft surfaces. Using the proposed AHO approach, functionally graded materials with common distributions can be efficiently optimised. By then, the proposed model is implemented on the MATLAB platform, and its execution is calculated using the current procedures. The proposed technique displays superior outcomes in all existing methods like wild horse optimiser, particle swarm optimisation and heap‐based optimiser. The proposed method shows a throughput of 57 mm3. The existing method shows the throughput of 32, 27 and 45 mm3. The results show that the proposed method has higher throughput compared with existing methods. [ABSTRACT FROM AUTHOR]

During the latest decades, regional creativity has often been considered as the precondition for innovativeness and sustainability. However, quantitative indicators of creativity are the subject of discussion. The paper aims to analyse the patterns and causes of European regional creativity distribution, revealing the influence of endogenous determinants on regional innovative development. An empirical analysis of regional patenting activity and a selection of indicators of regional creativity is conducted. Among the indicators, we include the development of regional institutions that are assessed through the data of the European Quality of Government Index. Besides the learning ability of the region (indicators of higher education prevalence and digital skills), the abundance of the creative class, regional innovative infrastructure, and population agglomeration were taken into account. The paper concludes concerning the most crucial factors contributing to endogenous sustainability through the lenses of European regions. In general, the formed model turned out to be significant with an acceptable level of standard error and a high predictive value. The influence of most of the parameters (except for the intelligence) was positive and significant. It is especially worth highlighting the parameters of regional institutions' quality and volumes of private research and development expenditures, which exert the greatest positive influence on the resulting variable. [ABSTRACT FROM AUTHOR]

This paper investigates the adoption patterns of Leadership in Energy and Environmental Design (LEED) certification in China, analyzing data from 2010 to 2021. We find that builders' choices of certification levels are positively correlated within each province. However, for commercial buildings, builders differentiate from each other in the choice of certification levels. The study also identifies spatial spillovers of LEED certification across nearby provinces. We propose potential explanations for these findings and discuss their policy implications. The results suggest that the design of certification schemes should account for the strategic behavior of firms. Additionally, regional policies promoting green building certifications may have spillover effects, encouraging adoption in neighboring regions. [ABSTRACT FROM AUTHOR]

Fluidized-bed agglomeration of native potato starch (NPS) with sugar binders [maltodextrin (MD) and lactose] produced larger particles with a more porous and diverse shape. Moreover, the agglomerated potato starch (APS) exhibited improved flowability and solubility. All powders displayed a B-type X-ray diffraction pattern. Although lactose did not impact the crystallinity of APS, that of APS prepared with MD decreased as the MD concentration increased. NPS showed higher gelatinization temperatures than APS prepared with distilled water (the control). Moreover, as binder concentration increased, the gelatinization temperatures and enthalpy of APS increased and decreased, respectively, indicating a delay in gelatinization. Similar results were observed with the pasting properties, wherein APS with sugar binders exhibited lower pasting, breakdown, setback, and final viscosities compared to the control. These were likely a result of decreased amylose leaching from the granules during heating due to the presence of sugar. [ABSTRACT FROM AUTHOR]

Clusters in the developing world do, to a large extent, attract low‐educated individuals, and these clusters are in some cases, characterized by urbanization without industrialization. This contrasts starkly to clusters in advanced economies that attract high‐skilled individuals and entrepreneurs. In this paper, we develop a model of agglomeration and spatial sorting that is consistent with these two types of different agglomeration processes in developed and developing countries. We show that a poor country that has an agglomeration with low skilled individuals, may get stuck in this equilibrium, but that free mobility of human capital from the outset nevertheless is superior from the perspective of total social welfare. [ABSTRACT FROM AUTHOR]

Lithium carbonate is an important material in the lithium battery. The materials can be obtained from a reactive crystallization process. To prepare the higher-quality crystals, such as purity, crystal size distribution, and desired morphology, it needs to be controlled effectively in the crystallization process. Therefore, a study of crystallization kinetics was required. Here, the metastable region was explored first. Subsequently, a LiCl-K2CO3-H2O reaction system in a continuous stirred-tank crystallizer with controlling pH was used to study the crystallization kinetics, such as nucleation rate (B0), agglomeration kernel (β), and crystal growth rate (G), which can be determined with measured crystal size distribution at a steady-state condition using an agglomeration population balance model. The process variables include lithium chloride solution flow rate, potassium carbonate solution flow rate, and stirring speed. The results show that B0, β, and G were in the range of 3.47 × 109–5.98 × 1012 no/m3·s, 1.78 × 10−19–1.20 × 10−12 m3-slurry/no·s, and 3.00 × 10−11–2.11 × 10−10 m/s, respectively, depending on the operating conditions. All relative supersaturations were in the range of 1.22–2.04. In addition, the crystal size observed was found to be in the range of 1.28–32.7 μm, with irregular platelet forms in most cases. In addition, more slurry density can be obtained at the feed rate of 40 mL/min. A linear regression for crystallization kinetics was also discussed in this work. Finally, this process demonstrated that the recycling of lithium was possible for a circular economy. Therefore, the result can be used as a reference for larger-scale operations in industry. [ABSTRACT FROM AUTHOR]

The subject of the study is the search for mechanisms of financial and economic regulation of the development of urban agglomeration, which, due to the chronic insufficiency of funds for these purposes of municipal budgets, is of particular importance. The purpose of the work is to justify the need to use non-traditional tools for regulating the coordinated development of municipalities forming the urban agglomeration. At the same time, it is shown that not only state regional government and municipal self-government bodies are the subjects of economic activity in each urban agglomeration: among them there are quite independent economic entities that need to be invited on the principles of public-private and municipal-private partnership to participate in the coordinated management of the development of the entire agglomeration in the interests of all stakeholders. The study is conducted on the basis of generalisation of the literature on the analysis of the methods used to manage the development of the urban agglomerations. Publications in which the analysed problems found forms of their resolution are the sources of information. The results of the study have heuristic potential due to the possibility of using the considered tools for financing the development of agglomeration for the coordinated development of the municipalities that do not form the urban agglomeration. The possibility of applying non-traditional forms of financing the coordinated development by increasing the capitalisation of municipal assets is the conclusion of the study. The relevance of the considered topic is due to the need to ensure the use of the entire arsenal of market instruments for purposeful development of the municipalities at a new stage of state development.

Introduction. The concentration of population and economic activity in agglomerations is primarily due to comfortable living conditions and developed infrastructure. At the same time, the issues of housing development in recent years have gone beyond the discussion of the problems of development of the construction industry and have become the subject of spatial development research. Housing stock and infrastructure facilities in the periphery do not correspond to demographic and migration processes. Thus, there is a need to develop analytical tools capable of planning a balanced infrastructure of the region.Materials and methods. Two research methods were used to investigate the set tasks: 1) studying the dynamics of key indicators of the region’s development; 2) calculation of the value of indices reflecting the concentration of the studied indicator (Herfindahl – Hirschman index — for the volume of housing construction, population concentration and the number of jobs; concentration coefficient of economic activity indicators).Results. The analysis of the main factors has shown that the long-term growth of the share of the population older than working age occurs in parallel with the growth of the population younger than working age. This imbalance is certainly the achievement of the state’s priorities in the field of improving the quality of life of the population through the introduction of social support measures for elderly citizens and young families. In agglomerations, jobs are technological and productivity is higher. Residence in the metropolitan area is considered not only as a place of work but also as a comfortable place to live.Discussion and Conclusion. The study of the regions of the Republic of Tatarstan allowed to show a complex situation with spatial development of the region — concentration in agglomerations and destruction on the periphery. In this regard, the study of agglomeration processes should become one of the elements of the national regional policy.

The paper presents a study of differences in the economic development of municipalities in the Novosibirsk region. Based on official statistics, maps of the distribution across the territory are built for population, employment, revenue, profitability of sales, and the share of unprofitable enterprises. The conclusion is that there is a high degree of concentration of business activity around the regional capital. At the same time, not all municipalities of the Novosibirsk agglomeration are leaders in terms of growth rates and business efficiency, which raises the question of exhausting the resource of the positive effects of the agglomeration economy. Descriptive methods are complemented by an econometric analysis of the role of spatial factors in the economic development of territories. Regression estimates revealed the heterogeneity of the influence of external markets, the positive effects of inter-district relations dominate within the Novosibirsk agglomeration, but the negative effects of inter-municipal competition are more pronounced outside it. Further concentration of economic potential in the Novosibirsk agglomeration without a longer transmission of growth impulses to other urban and rural settlements will lead to a restraint on the development of the entire territory of the region. Regional policy should include institutions and mechanisms for the transition from mostly competitive relations between municipalities to the predominance of cooperative interests. It is also necessary to create conditions for the creation of new centers of economic growth in the region, their role can be performed by municipalities with a relatively high population, with a developed road network and with a predominantly industrial specialization of business activity

The main objective of this research is to analyze the economic agglomeration pattern of competitiveness of the main export products of West Sumatra province, focusing on the role of improving trade facilities and transportation infrastructure to and from the export port. How strong is its competitiveness, able to interact to serve national, regional, and global trade, what strategies will be adopted to increase export competitiveness? The approach to measuring agglomeration export competitiveness used the Lapay Index, Moran, and LISA Index, as well as factors influencing the creation of agglomeration using the spatial lag model and spatial error model, as well as strategies for increasing export competitiveness using the Promethee model. The population in this study is export activities throughout Indonesia, but the sample from this study focuses on the West Sumatra region. The research results show that aspects of existing transportation infrastructure and trade facilities have placed the competitiveness of West Sumatra province lower at the national and regional levels. Export ports have not interacted heavily with national and regional export port nodes. Strategy to increase the agglomeration of West Sumatra's export competitiveness through increasing ship units loading and unloading at export ports, increasing the number of containers, increasing warehousing, improving the regulatory environment, and increasing ICT capabilities at export ports.

Globalisation has led to the dominance and geographical expansion of urban areas. Companies consider a complex set of criteria when deciding on their locations, including the agglomeration area and the presence of similar companies or related businesses. This study examines the spatial distribution and industrial clustering of companies within the agglomeration of Győr, Hungary’s sixth-largest city. The sample comprises 256 companies across 68 settlements, with data processed through map, quadrat and industry analysis. The analyses identified six settlements within the agglomeration where nearly half of the companies are located, five factors that seem to facilitate company location, and five main industrial sectors, four of which are closely related. The article concludes that the agglomeration area of Győr is characterised by a high degree of spatial concentration of companies, industrial clustering and the emergence of industry sub-centres.

Renewable biomass is a potent, CO2 neutral substitute to fossil coal and coke in iron making. However, there has been relatively little work on the utilization of biomass for the production of directly reduced iron (DRI). The aim of the present work is to characterize Acacia nilotica (W1), Albizia lebbeck (W2), and Leucaena leucocephala (W3) biomass and to reduce iron ore pellets primarily with the volatile matter from the wood at high temperature, yielding charcoal simultaneously as a co-product. The chemical, physical, and mechanical properties of the three biomass species were investigated. Effect of different biomasses and reduction parameters like C/O ratio, reduction temperature, and time on %Reduction (%R) was studied. DRI was characterized using %Metallization (%M), XRD, and SEM. Up to 89% reduction was achieved in the simultaneous carbonization of biomass and the reduction of iron ore pellets at a temperature of 1000 °C. The pellets cooled in the furnace after reduction resulted in lower %R (e.g., W1:57%, W2:54%, and W3:63%) than the respective air-cooled pellets (e.g., W1:88%, W2:83%, and W3:86%). Oxidation was the cause for lower %R in furnace cooled (slow cooling) reduction experiments than in the air cooled. Co-produced wood charcoal after the reduction of iron ore contained approximately 76–81% carbon which competes well with a typical value for coal of 70%. [ABSTRACT FROM AUTHOR]

Long afterglow nanoparticles, a type of luminescence material, may gradually release stored light energy even after the excitation light has stopped. The modification of polymer membranes by introducing long afterglow nanoparticles via an inorganic particle mixtures, broaden their uses in biomedicine field. In this study, a new membrane modification approach was employed to reduce the loss of physical–mechanical performance, caused by inherent strontium aluminate inorganic particle aggregation. Moreover, eugenol, a cross-linking agent, was used to interact with acrylate monomers to form locally cross-linked compounds using an ex situ approach that improves strontium aluminate particle dispersion. Furthermore, the soap-free emulsion polymerization method used, regulates the degree of cross-linking in the membrane, hence addressing nanoparticles agglomeration. Results showed that the cross-linked structure of the membrane produced improves the heat stability and the hydrophobicity of the material produced while also increasing the nanoparticles dispersion as evidenced by the XRD study. Nevertheless, membranes with cross-linking agents outperformed in water droplet trials by not breaking or whitening the droplets. Furthermore, the generated membranes exhibit high antibacterial activity, making them attractive for paramedical applications such as protective membranes applied on the top of the skin or on the surface areas of sensors, microneedles and metal fasteners. [ABSTRACT FROM AUTHOR]

In this article, we analyze how industry‐ and region‐specific characteristics influence individual‐level decisions on mobility within and between regions during the life cycle of the industry. Using uniquely detailed panel‐type data from the Finnish high technology sector, our analysis demonstrates that the influence of different regional features varies for different types of job changes and labor mobility and also according to the industry life cycle. We find that the classic agglomeration‐type arguments regarding labor search and matching only really operate in the early growth stages of an industry life cycle. These patterns change throughout the various stages of the industry life cycle, although in quite different ways according to different factors, and understanding how these patterns change helps to provide a richer understanding of the labor market roles of agglomeration and clustering. [ABSTRACT FROM AUTHOR]

The mountain communities of late-first millennium bc Italy have been regarded as non-urban societies that reverted to city life mainly owing to Roman intervention. A growing body of archaeological evidence is uncovering the diversity of settlement forms and dynamics in the region's pre-Roman past, which included sites encompassing a range of functions and social agents. This article presents an in-depth, microscale analysis of one such site, Monte Vairano in Samnium, drawing on perspectives from comparative urbanism. Monte Vairano developed urban characteristics such as a complex socioeconomic profile and political cohesion, as well as potentially more unique features such as an apparently balanced distribution of wealth. These results can shed further light on the diversity of ancient urbanization and its sociopolitical implications in late-first millennium bc Italy and the Mediterranean. [ABSTRACT FROM AUTHOR]

Fine particulate matter is challenging to capture due to its minuscule size, which affects its chargeability. The agglomeration method has been proven to be the most effective pretreatment technology for enhancing the removal of fine particles. This study proposes a novel dust-removal system that integrates turbulence-induced agglomeration into the wet electrostatic precipitator. The results showed that the removal efficiency of fine particles with a negative corona voltage was significantly higher, and removal efficiencies for particles smaller than 10.0 μm exceeded 90%. Furthermore, fine particles carried a larger charge when subjected to negative corona discharge, resulting in more-effective dust retention. The turbulence effect facilitates the removal of fine particles by promoting their agglomeration in turbulent conditions. The removal efficiency can increase significantly with turbulence, and this enhancement effect is more pronounced at higher flow rates. This study provides insight into the comprehensive removal of multiple pollutants from industrial flue gases. [ABSTRACT FROM AUTHOR]

This study analyzes the factors affecting industrial agglomeration in Indonesia using panel data from 34 provinces during the 2012-2023 period. The analytical methods employed include Location Quotient (LQ) and panel data regression, with testing results indicating that the Fixed Effect model is the most appropriate. The findings reveal that economic growth and investment have a negative and significant impact on industrial agglomeration, while the Human Development Index (HDI) shows a negative but insignificant effect. On the other hand, population size has a positive and significant influence on agglomeration. [ABSTRACT FROM AUTHOR]

This paper explores the competing sources of productivity gains observed in China's urban agglomerations focusing on three pillar industries: agro-food processing, textiles and electronics. The main results reveal that the higher aggregate productivity observed in denser Chinese cities is driven by both agglomeration and selection forces. Subsequent analysis shows that industrial support policies help to mitigate the selection penalty, but come at the expense of reducing agglomeration benefits. Complementing the city-level analysis, we estimate dynamic and distributive firm-level panel data models to explore the policy rationale of propping up inefficient firms, despite creating a less competitive environment. The micro-based results reveal that inefficient firms targeted by industrial support policies benefit from productivity spillovers in denser cities, mainly in the electronics industry, providing some policy rationale for keeping them in the market. [ABSTRACT FROM AUTHOR]

This paper shows that matching frictions and a thick market externality in firm‐to‐firm trade shape the agglomeration of economic activity. Using panel data of firm‐to‐firm trade in Japan, I demonstrate that firms gradually match with alternative suppliers following an unanticipated supplier bankruptcy, and that the rate of rematching increases in the geographic density of alternative suppliers. Motivated by these empirical findings, I develop a general equilibrium model of firm‐to‐firm matching in input trade across space. The model reveals that the thick market externality gives rise to an agglomeration externality affecting regional production and welfare. Using the calibrated model to the reduced‐form patterns of firm‐to‐firm matching, I estimate that the elasticity of a region's real wage with respect to population density due to the thick market externality is approximately 0.02. This finding highlights the substantial impact of the thick market externality on the overall agglomeration benefit. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of agglomeration on manufacturing firms' export mode decision-making. A detailed firm-level dataset combines the manufacturing and product-level transaction trade data from China. We use a dynamic multinomial logit model with random effects to analyze the effects of agglomeration on the transition probabilities of firms' exporting mode. The results indicate that the agglomeration of direct exporters positively affect firm's choice of exporting directly, and further indicate that the agglomeration effect is identified through productivity spillover. Moreover, these effects are not destination-specific, but are industry-specific. [ABSTRACT FROM AUTHOR]

This article examines the impact of prehistoric geographic isolation on technology adoption in both the historical period and contemporary period. The regression results show that geographic isolation tends to have a persistent positive effect on technology adoption, therefore, providing empirical support for the theory that geographic isolation is beneficial for economic development by stimulating innovations and improving technology. [ABSTRACT FROM AUTHOR]

AbstractThis study examines active vibration control (AVC) in a truncated conical shell composed of metal foam reinforced with agglomerated graphene nanoplatelets and integrated with piezoelectric layers functioning as sensors and actuators. Both complete and partial agglomeration states are considered based on the Eshelby–Mori–Tanaka approach, and the mechanical properties of the porous core are characterized using a closed-cell metal foam model. The governing equations of motion are derived using Hamilton’s principle, based on the two-dimensional axisymmetric elasticity theory, and solved through the finite element method coupled with the Newmark method. Vibration mitigation is achieved using a fractional-order fuzzy proportional–integral–derivative (PID) controller. A comprehensive parametric study is conducted, examining the effects of geometric dimensions, various boundary conditions, reinforcement parameters (including weight fraction, distribution patterns, and agglomeration parameters), and porosity parameters (including pore size, and porosity pattern) on the vibration properties of the shell. Numerical simulations are performed to assess the effectiveness of the proposed AVC system in reducing structural vibrations compared to a constant velocity feedback control approach. The velocity feedback controller reduced central deflection from 12.65 to 5.089 μm, while a fractional-order fuzzy PID controller further improved it to 2.348 μm, representing a 53.86% enhancement over the velocity feedback controller. [ABSTRACT FROM AUTHOR]

The present work deals with evaluating the nonlinear deflections of the smart sandwich plate with agglomerated Carbon Nanotubes (CNTs) porous core and piezo-magneto-electric (PME) facings, using a novel finite element method (FEM) – artificial neural network (ANN) approach. For the first time, an ANN-based computational tool that integrates the effects of agglomeration of CNTs, porosity and pyro-coupling of the PME materials is presented. Firstly, an in-house finite element (FE) computational tool is proposed and developed using the principle of virtual work in association with higher-order shear deformation theory (HSDT) and von-Karman's nonlinearity. The data points owing to the nonlinear deflections are collected using the proposed FE formulation, which trains the ANN model using Levenberg–Marquardt algorithm. The externally applied thermal loads are assumed to vary uniformly and linearly across the thickness of the plate. The primary focus of this work is to assess the variation in the degree of pyro-coupling associated with agglomeration and porosity. Two states of agglomeration, such as partial and complete; three forms of porosity, such as uniformly distributed, and two variants of functionally graded porosity, are considered for investigation. Numerical examples are solved to understand the interrelated effects of these material properties. A significant variation in the deflection of the plate, which refers to its actuation capability, is witnessed when the parameters of agglomeration and porosity change. [ABSTRACT FROM AUTHOR]

In the present article, the panel flutter behavior of nanocomposite hybrid laminated quadrilateral panel is studied. A three-phase carbon-nanotube (CNT)/polymer/fiber laminated composite is considered where the probable agglomeration of the CNT phase in the nano-matrix mixture is also addressed. Diverse use of fiber phase material in different plies is assumed in the context of hybrid laminated composite. A combination of nanocomposite polymer matrix, tow-steered curvilinear reinforcing fibers within the plies, and hybrid multi-material laminate is considered. The panel flutter behavior of the arbitrary quadrilateral hybrid laminated nanocomposite plate is formulated by a non-uniform rational B-splines-type isogeometric analysis method based on the first-order shear deformation plate theory. The nonideal mixture of the nanocomposite is also concerned about through applying a micromechanics approach. Representative results are obtained and compared with those available in the literature to demonstrate the quality of the proposed formulation. The effects of different parameters including the layup, mixture quality, boundary condition, geometry, and flow direction on the flutter behavior are investigated by performing parametric studies. [ABSTRACT FROM AUTHOR]

This paper presents the results of my research in the urban area of Győr. My research is based on semi-structured interviews with decision-makers (mayors, deputy mayors) and professional leaders (e.g. chief architects, notaries) of more than 10 municipalities. The aim of the research was to typify, collect and analyse the challenges that municipalities face due to suburbanisation in a comparative analysis. Another important objective was to identify good practices, in particular to capture the specific challenges of different agglomeration municipalities. In most cases, health, education and transport services are the most affected by growing population demand, while more affluent neighbourhoods are looking for better leisure, cultural and sports facilities. The integrated, vision-driven development of these emerging agglomeration areas is hampered by the funding structures and 'project mentality' of the municipalities studied. The main finding of my research is that medium-sized agglomeration municipalities face the main challenges in the study area, where everyday municipal management also poses significant challenges in everyday life. [ABSTRACT FROM AUTHOR]

Unbalanced development and growth among regions may cause the spread-backwash effects from developed-rich areas to the poor that commonly occur in the central city to its suburbs in the regional development context. Our study estimates the long-term effects of a small city, Yogyakarta, as a special region in Indonesia towards its periphery areas. The time-series econometric method is used based on Gross Regional Domestic Product (GRDP) and population data among five regions over the last thirty years instead of the cross section model. An alternative spatial combination among regions evaluated the regional development process. Development of the central city confidently has a long-run cointegration relationship with its suburbs. This study has indicated that Yogyakarta has spread-backwash effects towards its outskirt areas, either medium or low-level suburbs. Furthermore, a central city is no longer considered a single determinant in influencing the economy of other regions. The development of Sleman tends to be a new centre and shows that it produces a spillover effect to other areas; thus, it can be a potential trigger to improve linkages and economic performance of greater Yogyakarta. Yogyakarta City and parts of Sleman and Bantul areas are directly adjacent to the Yogyakarta City formed Yogyakarta urbanised area (YUA) as an urban agglomeration in Yogyakarta. The emergence of the YUA in greater Yogyakarta urgently promotes a sustainable collaboration and spatial interaction across territorial administration to manage economic and environmental interest conflict towards sustainable development among municipalities/cities level. [ABSTRACT FROM AUTHOR]

Products from certain areas are assumed to share qualities by virtue of where they are made. This article considers the economic significance of such place brands in the wider market for symbolic goods. It forwards a theory of these as judgement devices, whereby place reputation serves to lower search costs in symbolic goods markets with excess supply. This theory is investigated through a study of an online music platform where a weak form of place branding is available to producers. Results suggest that branding is associated with musical success at the individual level and that place brands may act as strategic resources for producers from creative clusters. Branding effects do not necessarily depend on the content of the place brand signal (i.e., country acts branded from Nashville are not especially privileged) and may be based in simpler heuristic mechanisms where a listed origin is a stamp of quality or an aid in recognition. [ABSTRACT FROM AUTHOR]

Al2O3 ceramics are the most widely used structural ceramics because of excellent mechanical properties, acid and alkali corrosion resistance and high quality-price-ratio. Due to serious agglomeration and high content of sodium and potassium impurities in domestic calcined Al2O3 powder, the preparation of Al2O3 ceramics with high performance relies heavily on imported powder. In this work, the Al2O3 powder produced by a domestic company was firstly disaggregated using ball milling, and the median particle size D50 of the powder was reduced from 1. 88 μm to 0. 90 μm. Afterwards, the impurity content in the powder was reduced by washing with water, and the Na content was reduced from 140 x 10-6 to 60 x 10-6, which was close to the level of the same grade powder abroad. Finally, Al2O3 ceramic green bodies were prepared by spontaneous coagulation casting using MgO and MgAl2O4 as sintering aids. It is found that the addition of MgO increases the slurry viscosity, while MgAl2O4 does not affect that, and both can effectively reduce the sintering temperature and inhibit the grain growth. And the average grain size is reduced from 41. 10 μm to 10. 64 μm, which improves the mechanical properties of Al2O3 ceramics. Through disaggregation and purification, the domestic Al2O3 powder can reach the same level as the Japanese Sumitomo Al2O3 powder with the best performance in the same grade. [ABSTRACT FROM AUTHOR]

Piperazine pyrophosphate (PAPP), as a good intumescent flame retardant, is widely used in polyolefin flame retardancy. However, its tendency to agglomerate greatly limits its application in materials. The application of unevenly dispersed PAPP in polypropylene can cause agglomeration, which not only results in white spots in polypropylene products, but also leads to a decrease in flame retardancy. The article combined the analysis of the causes of agglomeration of PAPP and added commonly used dispersants to improve its agglomeration phenomenon. Among them, dispersants included microscale silicides, large-sized silicides, zinc stearate, magnesium stearate, silicone oil, aminosilane, silicone, etc. Firstly, micro-sized silicides, silicones, and silicone oil were screened through heap pressure experiments to have a good effect on improving agglomeration. Furthermore, the influence of dispersants on polypropylene materials was characterized through methods such as thermogravimetric analysis, particle size testing, limited oxygen index testing, UL-94 testing, mechanical properties testing, and melt index testing. The results showed that silicone, silicone oil, and micro sized silicides had a significant improvement effect on the agglomeration of PAPP. Applied in polypropylene, micro sized silicides had the least impact on flame retardant polypropylene and the lowest degree of physical property degradation. Therefore, micro sized silicides were selected as the best additives for improving PAPP. [ABSTRACT FROM AUTHOR]

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Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The combustion completeness of Al agglomerates affects the performance of solid rocket motor, reducing the agglomerate sizes is effective to enhance the performance. In this study, agglomeration and combustion characteristics of Al particles near the burning surface of ammonium perchlorate (AP) composite propellants were observed using a pulsed laser system. Moreover, to suppress the agglomerate diameter and use the micro-explosion characteristics of Mg-Al particles, Al was partially replaced with magnesium-aluminum (Mg-Al) alloy Moreover, the relation between the proportion of Mg-Al particles and agglomeration diameter of Al particles was investigated. Measurement results showed that a small amount of Mg-Al mixture successfully reduced the agglomerated Al particle size. Furthermore, the agglomeration process that accumulates on AP particles was observed in the aluminized propellant through burning surface observation. Thus, the addition of Mg-Al particles was confirmed to be effective in suppressing the agglomeration process. [ABSTRACT FROM AUTHOR]

Nanoparticles are increasingly implemented in biomedical applications, including the diagnosis and treatment of disease. When exposed to complex biological media, nanoparticles spontaneously interact with their surrounding environment, leading to the surface-adsorption of small and bio- macromolecules- termed the "corona". Corona composition is governed by nanoparticle properties and incubation parameters. While the focus of most studies is on the protein signature of the nanoparticle corona, the impact of experimental protocols on nanoparticle size in the presence of complex biological media, and the impact of nanoparticle recovery from biological media has not yet been reported. Here using a non-degradable robust model, we show how centrifugation-resuspension protocols used for the isolation of nanoparticles from incubation media, incubation duration and shear flow conditions alter nanoparticle parameters including particle size, zeta potential and total protein content. Our results show significant changes in nanoparticle size following exposure to media containing protein under different flow conditions, which also altered the composition of surface-adsorbed proteins profiled by SDS-PAGE. Our in situ analysis of nanoparticle size in media containing protein using particle tracking analysis highlights that centrifugation-resuspension is disruptive to agglomerates that are spontaneously formed in protein containing media, highlighting the need for in situ analytical methods that do not alter the intermediates formed following nanoparticle exposure to biological media. Nanomedicines are mostly intended for parenteral administration, and our findings show that parameters such as shear flow can significantly alter nanoparticle physicochemical parameters. Overall, we show that the centrifugation-resuspension isolation of nanoparticles from media significantly alters particle parameters in addition to the overall protein composition of surface-adsorbed proteins. We recommend that nanoparticle characterization pipelines studying bio-nano interactions during early nanomedicine development consider biologically-relevant shear flow conditions and media composition that can significantly alter particle physical parameters and subsequent conclusions from these studies. [Display omitted] • We investigate the impact of protein corona experimental pipelines on particle colloid stability. • We show that physiologically relevant flow conditions alter nanoparticle parameters. • Using a model system, we demonstrate that more gentle separation or in situ techniques are needed for analysis of the nanoparticle protein corona. [ABSTRACT FROM AUTHOR]

An extensive investigation into the bending behavior of nanoshells made of coated functionally graded (FG) carbon nanotubes reinforced composites has been conducted, employing a novel spatial variation in material properties. The study explored Hardcore and Softcore of coated FG nanoshells. The examination includes five distribution patterns: a fully coated tri-directional, two bidirectional patterns, a transverse unidirectional, and an axial unidirectional distribution. The shell is resting on an orthotropic Winkler, Pasternak and Kerr foundations. Galerkin method is employed to establish an analytical solution for the equilibrium equations. This approach is designed to accommodate a variety of different boundary conditions. A comprehensive examination is undertaken to demonstrate the effects of various geometric and material parameters on the deflection and stresses of nanoshells. [ABSTRACT FROM AUTHOR]

A milled recycled asphalt pavement (RAP) particle can be a cluster of one or more aggregates coated with an aged RAP binder. While RAP material is added to virgin aggregates and binder in a pugmill, the RAP cluster undergoes dissociation or agglomeration, depending on the cluster size and thermo-physical conditions inside the pugmill. The degree of dissociation or agglomeration of RAP material has an important relation with the degree of RAP binder availability. The RAP binder availability in mix design depends on the exposed surface area of dissociated coarse RAP particles and also on the agglomeration tendency of fine RAP particles. In the present study, the degree of RAP binder availability (DoAv), cluster dissociation of course RAP, and agglomeration tendency of fine RAP particles were examined at different mixing durations inside an asphalt pugmill—60 s, 120 s, and 180 s. The study examined whether the RAP cluster dissociation and postmixing agglomeration has any effect on the RAP binder availability. The degree of RAP binder availability of RAP mix was found by determining the virgin binder requirement of RAP mixes in excess of optimum binder content determined for the control mix prepared using virgin aggregates. Cluster dissociation and agglomeration was studied by hot mixing of RAP fractions in a pugmill with abrasive charges, followed by sieving. The statistical analysis of data found that RAP mixes incorporating fractionated fine RAP material exhibited higher DoAv at every mixing duration. For mixes incorporating fractionated coarse RAP, cluster dissociation index was positively correlated with DoAv, which implied that RAP cluster dissociation is a possible reason for RAP binder availability. In mixes incorporating fractionated fine RAP fractions, the RAP particles got agglomerated. The agglomeration index was found to correlate well with RAP binder availability, thereby establishing that agglomeration tendency in fine RAP fractions can be considered as an indicator of RAP binder availability. [ABSTRACT FROM AUTHOR]

Within the high-speed rail debate (HSR) there has been lacking in-depth theoretical and evidential research on the role HSR has on tacit knowledge flows between industrial clusters or regions of economic productivity. The research that has begun to emerge has focused on knowledge indicators such as patents for social/tacit knowledge exchange, which this paper raises concerns over. This review aims to discover new links for HSR with cluster economics through social knowledge theory and aims to create a conceptual framework that will provide a new perspective for future research in the HSR debate concerning social knowledge exchange. Potential implications are presented for future transport policy decision-making, based on the relationship HSR may have with inter-regional tacit knowledge flows and accessibility benefits in regional balancing. Future research considerations are pointed out that argue to measure the flow of knowledge from HSR, research needs to go in-depth to the social aspect of interactions and relationship buildings, as quantitative data will struggle to capture tacit knowledge flow itself, due to the tacit nature of such information. The presented framework highlights the tacit nature of interactions facilitated by HSR connectivity. [ABSTRACT FROM AUTHOR]

In the current scenario, industries face new challenges in cutting metal-based composites with good surface texture. The experimental investigation on laser cutting of magnesium AS2-Bimodal SiC composites is reported in the present work. Three bimodal compositions with varying proportions of micro-nano SiC reinforcement (75%-25%, 50%-50% and 25%-75%) were dispersed in AS21 alloy by stir-casting route. The comparison of quality characteristics such as surface roughness, kerf deviation and edge slope has been done to examine the behaviour of bimodal reinforcement with different laser cutting parameters. The experimental strategy was implemented based on the Taguchi L18 mixed design. The microstructure and cutting surface morphology has been analysed using OM, SEM and TEM. The results demonstrated that the AS21 composite with a bimodal structure of 75 vol.% micro-SiC and 25 vol.% nano-SiC showed better performance characteristics of CO2 laser cutting system due to uniform grain structure and homogeneous dispersion of nano-SiC reinforcement. [ABSTRACT FROM AUTHOR]

Russia is one of the world leaders in the production of sunflower oil, and the utilization of sunflower husks seems to be a very pressing problem. The husk has low humidity (4.4‒12.2%) and a fairly high calorific value (16–19 MJ/kg), but its ash contains a significant amount of potassium, calcium, and magnesium compounds, which cause slagging of the boiler furnace and rapid growth of ash deposits on its convective heating surfaces. Agglomeration and slagging are especially acute when burning crop waste in a fluidized bed of quartz sand, causing defluidization of the layer. This leads to frequent boiler shutdowns to clean the furnaces. Alternative materials to quartz sand are known, but the literature contains little data on their commercial application. The operation of a combustion device with a fluidized bed of quartz sand and olivine as part of a 2-MW heat-generating installation when burning sunflower husks is analyzed. The chemical composition of agglomerates is studied and the mechanism of their formation is described. The experiment on burning husks in a layer of olivine lasted continuously for 600 h. When carrying out periodic measurements of the fractional composition of the olivine layer, the concentrations of carbon oxide, dioxide, and oxygen in the flue gases and the formation of agglomerates was not detected. [ABSTRACT FROM AUTHOR]