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To discuss nonmetallic inclusion behaviors in a secondary refining process, cold model experiments on agglomeration, breakup, and transfer of fine particles are performed varying the operating factors such as an energy input rate, wettability, agitation practice, and the number of liquid phases. When the other operating conditions are the same, the agglomeration rate of the 1‐particle (isolated particle) with a hydrophobic property is larger than that with a hydrophilic one, and the transfer rate of the 2‐particle (cluster of 2 isolated particles) has the same tendency. The number of the 1‐particle with the hydrophobicity is estimated to increase at the transfer site of the particles from an open eye to a heavy liquid due to a bubble breakup, whereas the 1‐particle with the hydrophilicity shows an opposite trend because of less adhesion on the bubbles. The 1‐particle in the dual phase transfers from the open‐eye spot to a light liquid, although the value is not so much as that of the decrease in the agglomeration. A transfer condition of the inclusion composed of Al2O3 or CaO⋅Al2O3 is calculated when a particle contacts with a solid/liquid interface, and the CaO⋅Al2O3 inclusion is estimated to be engulfed above 3.34 μm in diameter. [ABSTRACT FROM AUTHOR]

We estimate the spatially heterogeneous effects of the coronavirus disease 2019 pandemic on labor market dynamics in Germany until December 2021. While initially slightly stronger in rural regions and large agglomerations, adverse effects quickly become more pronounced and persistent in large agglomerations compared to all other region types. We ascribe the larger impact of the pandemic in large agglomerations to two factors. First, a combination of a higher share of skilled workers and jobs suitable for working from home is positively related to an increased inflow rate into unemployment. We argue that local spillover effects from reduced product market demand in large cities caused by changes in behavior such as working from home or online shopping are a possible explanation. Second, some of our results suggest that a lower outflow rate out of unemployment is associated with a higher precrisis unemployment rate in large agglomerations. This might reflect the less favorable composition of unemployment in large cities, which reduces the probability of transitions into employment during crises. [ABSTRACT FROM AUTHOR]

Sudden events are being observed more often (pandemics, armed conflicts, high inflation, etc.). Urban transport systems are especially susceptible to sudden disruptions as manifested by sharp changes in user preferences and demand for transport services. Mobility as a service (MaaS) aims to improve the efficiency of urban transport systems and support the integration of various forms of transport. The main goal of the research is to assess the level of MaaS use and check what characteristics could influence using MaaS by different groups of users. A case study of the Tri-City, the largest urban centre in northern Poland, was used to examine the possibility of implementing MaaS. We assumed that the use of IT applications would help to reduce the challenges faced by mobility in modern cities. We hypothesised that MaaS is conducive to integrating transport in the city. Knowledge of MaaS acceptance is essential in implementing this concept and can help local authorities respond to sudden disruptions by increasing flexibility in shaping urban mobility. Poland still lacks a universal multimodal solution that would help optimise travel within the cities and actions should be undertaken to popularise digital solutions that improve the efficiency and organisation of PT. [ABSTRACT FROM AUTHOR]

The effect of the Competitive Paraná Program (CPP) on the industrial dynamics of the municipalities is analyzed here, with emphasis being placed on those of low previous industrial expressiveness. For this purpose, the Propensity Score Matching method was used in order to examine the formation of specialized and diversified agglomerations, industrial concentration, productivity, and the participation of industry in the state's economy. As a corollary, the program effectively contributed to the industrial development of municipalities, by changing the productive structure dynamics, especially in municipalities with a consolidated ex-ante secondary sector. [ABSTRACT FROM AUTHOR]

To date, the utilization of carboxymethyl cellulose (CMC) fibers are only restricted to weak mechanical application such as wound dressing. Physically, CMC has a weak mechanical strength due to the high hydrophilicity trait. However, this flaw was saved by the extensive number of reactive functional groups, allowing this macromolecule to form linkages with chitosan to ensure its versatility. This work successfully fabricated CMC-chitosan fiber via dissolution, crosslinking, dry-jet wet-spinning extrusion, and coagulation processes. Chitosan was constituted with CMC fiber in two approaches, coating, and inclusion at various concentrations. Morphologically, chitosan incorporation has triggered agglomerations and roughness toward CMC fibers (CMCF). Chemically, the interaction between CMC and chitosan was proved through FTIR analysis at peaks 1245 cm−1 (ECH covalent crosslinking), while 3340 cm−1 and 1586 cm−1 were due to ionic and hydrogen bonding. The result from analysis showed that at higher chitosan concentrations, the chitosan-included CMC fiber (CMCF-I) and chitosan-coated CMC fiber (CMF C) were mechanically enhanced (up to 86.77 and 82.72 MPa), thermally more stable (33 % residual mass), and less hydrophilic compared to the plain CMCF. The properties of CMC-chitosan fibers have opened up vast possible applications, especially as a reinforcement in a watery medium such as a hydrogel. [ABSTRACT FROM AUTHOR]

Spark plasma sintered NiAl-CNTs intermetallic composites were fabricated via two different ball milling processes. One comprising of an exclusive low energy ball milling (LEBM), and the other comprising of a two-stage milling, typically a prolonged LEBM with a short term high energy ball milling (HEBM). The differently milled powders were consolidated, and the resulting composites characterized. This was done to determine the individual effects of agglomerations vis-à-vis the structural integrity of the nanotubes. The composites were extensively characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy (RS), scanning electron microscopy (SEM) and nanoindentation techniques. The uniform dispersion of slightly impaired CNTs led to better mechanical properties as compared to the in-homogenous dispersion of higher structural integrity CNTs in the NiAl intermetallic matrices. Results showed that the sample with a two-stage milling exhibited superior mechanical properties in terms of hardness, elastic modulus and fracture toughness with 422.79 Hv, 50.5 GPa and 9 MPa√m respectively. • 0.5 wt% multi-walled carbon nanotubes (MWCNTs) were dispersed in a nickel aluminide (NiAl) matrix using two different ball milling regimes. • The two different ball milling regimes imparted different defect concentrations and dispersion intensities on the nanotubes within the matrices. • Results show that the sample which experienced a two stage milling exhibited better mechanical properties. [ABSTRACT FROM AUTHOR]

Code smells are symptoms in the source code that could help to identify architectural problems. However, developers may feel discouraged to analyze multiple smells if they are not able to focus their attention on a small set of source code locations. Unfortunately, current techniques fall short in assisting developers to prioritize smelly locations that are likely to indicate architectural problems. Furthermore, developers often have trouble analyzing interconnected smells that contribute together to realize an architectural problem. To deal with these issues, this work presents and evaluates a suite of five criteria for ranking groups of code smells as indicators of architectural problems in evolving systems. These criteria were implemented in a tool called JSpIRIT. In a first experiment, we have assessed the criteria in the context of 23 versions of 4 systems and analyzed their effectiveness for revealing architectural problem locations. In addition, we conducted a second experiment for analyzing similarities between the prioritization provided by developers and the prioritization provided by our best performing criterion. The results provide evidence that one of the proposed criteria helped to correctly prioritize more than 80 code locations of architectural problems, alleviating tedious manual inspection of the source code vis-a-vis with the architecture. • We present 5 criteria for ranking groups of code smells as indicators of architectural problems. • We assessed the criteria in the context of 23 versions of 4 systems. • One criterion helped to prioritize more than 80 code locations of architectural problems. • One criterion helped developers to discard at least 500 code smells no related to architectural problems. [ABSTRACT FROM AUTHOR]

The objective of the research is to analyze the specialization and concentration of tourist employment in Mato Grosso do Sul. The methodological procedures were the Locational Quotient, Redistribution Coefficient, Location Coefficient and the Relative Participation of this employment in relation to the national employment. The results indicate specialization of the state's tourism employment, in municipalities like Corumbá, however, there are no concentration patterns. The redistribution coefficient showed that there were no changes in the pattern of location during the period, and the relative share of employment is not constant. [ABSTRACT FROM AUTHOR]

Abstract: The effectiveness of Science and Technology Parks (STPs) as instruments of innovation policy has generated thriving debate among academics, practitioners and policy makers. A gap in the existing literature on STPs is that research mostly does not consider STPs' heterogeneity. The present paper aims at filling this gap, analysing the influence of different STP characteristics on their tenants' performance. Using data on 849 firms and 25 STPs from the 2009 Community Innovation Survey for Spain and a survey of STP managers respectively and after controlling for a wide set of firms characteristics, we find that: (i) firms located in very new or longer established STPs show better innovative performance; (ii) the size of the STP and its management company positively affects the innovative performance of tenants while services provision has no effect on firms' achieving better results; and (iii) firms in less technologically developed regions benefit more from location in an STP. Theoretical, policy and managerial contributions of our research are discussed in the paper. [ABSTRACT FROM AUTHOR]

Micro- and small-scale enterprises (MSEs) in many regions provide the only job opportunities for large parts of the population and ensure the survival of numerous families. However, the existence of MSEs is increasingly threatened by an increasing global competition reaching previously local markets. This article gives an overview of general aspects of clustered MSEs in the global South and the effects of global competition. It emphasises the importance of considering the diversity of clusters as well as the socio-cultural context of entrepreneurs in order to understand entrepreneurial behaviour. The empirical qualitative analysis of the actual adaptation behaviour of MSEs in South America's largest textile cluster, Gamarra in Lima, reveals that strong competition forces entrepreneurs to concentrate all resources on maintaining the business, leading to a fatalistic participation in the price war on local markets. It further shows how the absence of public regulation together with socio-cultural barriers prevents entrepreneurial cooperation, and suggests rethinking the laissez-faire strategy of public actors. [ABSTRACT FROM AUTHOR]

This article considers the differences in the development levels of Russian cities with a population of over half a million that are regional centers and form "nuclei" of agglomerations. The level and dynamics of their development do not directly depend on the size of the city: some cities with a population of a million and more have socioeconomic development indicators that are inferior to those of smaller cities. The authors have calculated population and economic concentrations in agglomerations of large cities. Groups of agglomerations have been identified with different growth prospects taking into account the level of development of major "nucleus" cities and the degree of population and economic concentration in the agglomerations. The author identifies the obstacles that hinder the development of Russian agglomerations centered in municipalities with extremely limited financial resources and powers, which prevents them from competing with federal cities. Measures are proposed to develop agglomerations of cities that are regional centers. [ABSTRACT FROM AUTHOR]

The processes of economic globalization have transformed socio-economic spatial functioning of the territories. These trends caused international competition between countries, regions, and settlements. According to this, nowadays, the examination of competitiveness has become an important research question in economic geography. The aim of our study is to examine the scale-dependent processes of revealed competitiveness of agglomerations, agglomerating areas, and settlement groups in Hungary excluding the Budapest agglomeration. The study was based on quantitative research methods using an empirical database and mathematical statistical methods. Firstly, we conducted a Principal Component Analysis (PCA) of revealed competitiveness in different geographical scales and afterwards, we utilized the method of Spatial Autocorrelation on a settlement level. Our findings showed that there are significant spatial differences among the performance of the Hungarian urbanised areas. The east-west dichotomy considering competitiveness despite the European Unions’ developmental funds is still present between Agglomerations, Agglomerating areas, and Settlement groups in Hungary. Moreover, according to our calculations, intra-regional polarization and scale mechanism are in connection with revealed competitiveness and it is justified by spatial autocorrelation. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 nanoparticles can be easily dispersed on a Zeolite Na-A support material. • The supported TiO 2 on zeolite is more dispersed than unsupported TiO 2 nanoparticles. • Nanoparticle dispersion leads to increased light absorption, more active sites and high photodegradation performance. • The optimum performance of TiO 2 /Zeolite Na-A nanocatalyst was 1.5TiO 2 /Zeolite Na-a. Zeolite Na-A supported TiO 2 nanopowders were synthesized via a modified sol–gel technique and the effects of TiO 2 loading were characterized for thermal, structural, morphological, optical and textural behaviour. Thermal properties predicted a minimum annealing temperature of 600 °C whereas the X-ray diffraction (XRD) patterns indicated that the composite was highly crystalline, and consisted of both TiO 2 and zeolite Na-A peaks. Scanning electron microscopy (SEM) images confirmed that the TiO 2 nanoparticles occurred mainly on the surface of the zeolite Na-A support. Nitrogen adsorption–desorption studies portrayed increased porosity and larger surface area for TiO 2 /zeolite Na-A compared to pure TiO 2. The optical band gap decreased with increased TiO 2 loading from 3.17 to 2.85 eV. The synthesized nanopowders were applied in photocatalytic dye removal, where by the highest degradation rate for the supported TiO 2 was realized at 1.5 %TiO 2 /zeolite Na-A loading. It was found that loading beyond 1.5 %TiO 2 led to a structural collapse and decline in the photodegradation rate. [ABSTRACT FROM AUTHOR]

Ultrasonic vibration treatment is successfully applied in preparation of in-situ 5 vol% TiB 2 particulates reinforced Al-4.5Cu alloy matrix composites with salt-metal reaction route. Formation of TiB 2 phase is confirmed by X-ray diffraction analysis, and intermediate phases such as Al 3 Ti are not detected. Agglomerations of particles in the melt are effectively eliminated by the cavitation and acoustic streaming affects in the melt with ultrasonic vibration. TiB 2 particles are uniformly distributed throughout the bulk melt after treated by ultrasonic vibration for 240 s. The tiny agglomerations formed by TiB 2 particles smaller than 100 nm are also broken by ultrasonic vibration. Some TiB 2 particles smaller than 400 nm are observed to dispersed near grain boundary in the matrix after solidification. The optimal improvements of yield strength and ultimate tensile strength are 114% and 50%, respectively, when composite treated by ultrasonic vibration for 240 s. [ABSTRACT FROM AUTHOR]

• Diesel can enhance the benefit of gas nucleation on the flotation recovery. • Diesel can increase the air nucleation probability on graphite surfaces. • The formation of surface microbubbles can prevent the collector adsorption. • Combining gas nucleation and collector can promote the formation of agglomerates. This paper investigates the effect of an oil collector, namely diesel oil, on surface air nucleation and the influence of nucleation microbubbles on collector adsorption in froth flotation. In order to prepare the condition for air nucleation in flotation, air-oversaturated water was produced using tap water pressurized by high-pressure air in an autoclave. Micro-flotation, single bubble collision experiments, contact angle measurements, microscopic observations, and agglomerations analysis were combined to investigate the effects of the oil collector on air nucleation and agglomerates formation. Furthermore, the free energy changes in an ideal system were utilized to explain the mechanisms. The experimental results and free energy changes show that diesel oil can improve the air nucleation probability on graphite surfaces by decreasing the barrier for nucleation. Meanwhile, the oil collector can also significantly increase the fraction of agglomerates formed in air-oversaturated water to improve the recovery of fine particles. Besides, the results indicate that the formation of nucleation microbubbles before collector conditioning can occupy significant surface areas of the graphite particles and inhibit the collector adsorption on the mineral surfaces. [ABSTRACT FROM AUTHOR]

The paper aims to assess the synergic impact of institutions, geography and culture on the decision of localization of operations and individuals. For this purpose, we will identify factors influencing the spatial distribution of operations and suggest an analysis of typology and institutions favorable for economic performance. We conclude that the benefits resulting from agglomerations would not be possible without inclusive political and economic institutions that allow exploitation of market opportunities, encourage technological innovation and investment in people and mobilize talents and skills of a large number of individuals. [ABSTRACT FROM AUTHOR]

This article aimed to identify and analyze what are the public and private institutions that make up the APL Muriaé, city located in the Zona da Mata of Minas Gerais. It is noteworthy that the city is part of one of the poles of the references of the Brazilian textile market. The study had a qualitative approach with character descriptive. For data collection was carried out semi-structured interviews with 21 actors of APL. It was concluded that the APL has an institutional context consisting of a number of institutions working in different areas that, together with enterprises is a strategy to increase the competitiveness of small and micro enterprises in the current scenario of global competition. Moreover, it is noteworthy this study to contribution with support information so that actors understand the institutional context of the APL Muriaé. Moreover, it is in a support for the development of public policies aimed at consolidating the agglomerations in favor of local and regional development, which reflect the national level, in consequence of the important APL in the Brazilian manufacturing sector. [ABSTRACT FROM AUTHOR]

In-situ 5 vol% TiB 2 /Al–4.5Cu composites are successfully prepared by the salt–metal reactions assisted by improved mechanical stirring. The X-ray diffraction confirms the formation of TiB 2 particles, and no cluster or large precipitate of intermediate phases Al 3 Ti and AlB 2 can be traced. Mechanical stirring can reduce the large agglomerations and finally eliminate them when the speed rises to 540 rpm. Most of TiB 2 particles are uniformly distributed along the grain boundary in the matrix, and lots of dispersed particles with a size under 0.4 μm are also found. Yield stress and ultimate tensile strength of the composite are improved by 85% and 46%, respectively. [ABSTRACT FROM AUTHOR]

This study mainly investigated the effects of liquid evaporation and liquid bridge actions on hydrodynamics in liquid-containing gas–solid fluidized bed reactor (LGSFBR). A liquid flow-rate increasing process and a gas velocity decreasing process were studied by using temperature, acoustic emission (AE) and pressure fluctuation (PF) measurement techniques. When the liquid was added with lower flow-rates, particle circulation pattern was dominated by gas flow/liquid evaporation action, and thus particles display ascending at the center and descending near the wall (ACDW) with particle motion enhanced, meanwhile bubble sizes increased at the beginning and then decreased to steady values. With increasing liquid flow-rate or decreasing gas velocity, liquid bridge action relative to gas flow action intensity (LRGI) increased, and thus the particle circulation pattern gradually became dominated by the liquid bridge action. Specifically, the downward motion of dynamic particle agglomerations was enhanced while particle motion was weakened, and the gas bubble size was repressed gradually. Several unstable fluidization states would be caused by continuous increases in the liquid bridge action. [ABSTRACT FROM AUTHOR]

This article presents the preliminary results of the doctoral thesis entitled "The quality of life in the city of Bogotá: An evaluation based on the Multidimensional Poverty Index (MPI)," which aims to determine how large agglomerations benefit or work against the quality of life of human beings, based on the case study of Bogotá between 2003 and 2011. Bogotá has experienced significant population and economic growth since the end of the 20th century. This boom has allowed an improvement in the quality of life of its inhabitants, as evidenced by an analysis of MPI results, after disaggregating data by dimensions and indicators, as well as according to the neighborhoods that form the city of Bogotá. Despite the progress, the city faces the challenge of eliminating serious socio-spatial segregation; for this reason, public policies aiming to generate social equity need to be strengthened. [ABSTRACT FROM AUTHOR]

In Venezuela, new policy decisions embodied in laws enacted by the central government have been added to the traditional factors motivating the dynamics of metropolitan expansions. The implementation of those laws has contributed to accelerating the expansion of metropolitan borders, paradoxically reinforcing an improvised and uncoordinated process of incorporation of new low-income developments lacking in infrastructure, adequate facilities, and the services necessary to guarantee the quality of urban life. Furthermore, this has been done at the expense of ecologically valuable and vulnerable spaces. These areas constitute territorial emergencies that deserve specific and immediate attention since they are the territorial forms featuring the greatest and most recent changes, and should be the focus of interventions aimed at territorial ordering. [ABSTRACT FROM AUTHOR]

The objective of this study is to analyze scientific publications about clusters and local production arrangements (LPA's) in Brazil from 2000 to 2011. The study was conducted in journals classified by Qualis (Capes) in the areas of Administration, Economics and Engineering, with a total of 80 papers. The analysis made it possible to identify publication characteristics regarding methodological approaches and research methods, the most cited authors, researched clusters and LPA's and the most studied themes. A tendency was verified in recent studies: the use of theoretical approaches with greater emphasis on cooperation. It was observed that empirical research, in general, is restricted to identifying the existence of clusters in given locations and to describing them with basis on the chosen research themes. Therefore, there is an opportunity for advancing the research and for an effective contribution for theory development. [ABSTRACT FROM AUTHOR]

This article describes a new approach for analyzing data within national historical geographic information system databases that can be used to explore long-term trends in landscape evolution. The methodology is based on clustering together areas with similar demographic characteristics to define urban agglomerations whose territorial extents and populations vary over time. The resulting database can be used in a wide range of ways that allow the empirical study of urban growth and urban sprawl. The article is based on data for England and Wales but given the increasing availability of national historical geographic information system databases for countries around the world, the approach could be replicated for a wide range of different places. [ABSTRACT FROM PUBLISHER]

The purpose of this paper is to study the territoriality and the formation of territorial clusters.The idea goes beyond the purely economic territory. A territorial strategy requires the use of the opportunities and synergies between entrepreneurs, institutions and society. Promoting and encouraging territorial clusters are not enough to stimulate the process of socioeconomic development, but it is a decisive step to strengthening cooperation among economic agents and building new territoriality. [ABSTRACT FROM AUTHOR]

Europeanization is a valuable concept for explaining the impact of EU policies at domestic level and especially of regional policy development in Romania. The relative low discrepancies and the low levels of development that Romania faced after almost fifty years of centralized planning resulted apparently in no need for a regional policy. This policy was 'built' in order to meet the EU financial assistance and Romania had to re-think its centre-region relation and to acquire a new vision over the policy of regional development. The following paper will try to analyze whether the current regional policy managed to have the expected impact in Romania, with short emphasis on the concepts of regionalism, regional competitiveness and economic agglomerations. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to open the ‘black box’ of knowledge spillovers by testing the extent to which social interactions between firms in a region positively contribute to firm performance. Specifically, we examine the Marshall-Jacobs controversy, a debate over whether these spillovers occur across firms operating in similar or dissimilar fields. Our empirical examination of the debate relies on a dataset that is constructed from three sources: firm-level data of 1,881 high-tech firms in all 40 Dutch regions, regional economic data and network data constructed from the membership registrations of all business associations in a sample of 11 regions. The results show that the total amount of regional network activity has no effect on individual firm performance; however, participation in local business networks does support firm employment growth. With regards to the Marshall-Jacobs controversy, the results show that having local links to other high-tech firms is conducive to a firm's employment growth, while links to other types of firms provided no such lift. [ABSTRACT FROM AUTHOR]

Tourism firms operate in a business environment in which innovation is important for firm survival. In spite of this, there is an apparent lack of knowledge concerning innovation processes in tourism firms. This article combines considerations about the geographical characteristics of tourism with social innovation network and agglomeration theories so as to develop a theoretical framework of the social innovation network geography of tourism. The theoretical framework presents arguments for different types of social network geographies and their innovation benefits. An empirical study of tourism firms in destinations in the Province of Malaga, Spain illustrates the theoretical framework. The overall conclusion of the article is that there are several social network geographies of tourism. However, in the empirical study local networks are found to be loose and dense whereas non-local networks are strong and sparse. This social network geography secures access to varied information benefits sustaining innovation. The analysis of social network geographies of tourism does, however, only provide one little piece of the puzzle of understanding innovation in tourism firms. [ABSTRACT FROM AUTHOR]

This article proposes an empirical investigation of regional trade flows following a cross-section method. For this purpose, the author refers to a regional context looking at a chosen sample of European regions. She mainly intends to assess the role of the home market effect and the level of transport costs in driving regional export flows. In particular, she is interested in testing the importance of spatial components in regional trade analysis. By simply adapting the gravity model approach to her framework, she is able to prove that physical distance smooths the intensity of trading flows while local transport facilities as well as local demand foster them. [ABSTRACT FROM AUTHOR]

In this paper, the roles of agglomerations of ZrB 2 nanoparticles in the in - situ ZrB 2 -nanoparticle-reinforced AA6061 composites were investigated via the analyses of strain hardening and serrated flow behaviors during the deformation. The tensile testing demonstrates that the composite with 2 vol% of nanoparticles has a yield strength of 74.1 MPa, ultimate strength of 181.1 MPa and plastic strain of 20.2%, respectively, which are better than the composites with 1 vol% and 3 vol% of nanoparticles. The increasing values of strain-hardening coefficients suggest that the mobility of dislocations was decreased. The strain hardening rate indicates that the as-cast 2 vol% ZrB 2 -nanoparticles-reinforced composite has the best strain hardening ability but the composite with 3 vol% ZrB 2 nanoparticles has the lowest one which is attributed to the strain concentration in the agglomerations initiating the crack through the cohesive region between ZrB 2 nanoparticles. The serration analysis reveals that the population of serrations with ≤0.5 MPa of stress drop is a key feature for stabilizing plastic deformation. • Serrations with ≤0.5 MPa of stress drop is a key feature for plastic deformation. • Large agglomerations fragment matrix and cause large stress drop of serrations. • Stable mechanical properties require sufficient feedback of strengthening to drop. [ABSTRACT FROM AUTHOR]