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The use of nanocelluloses as strength-enhancing additives in papermaking is widely known since both cellulose nanofibers (CNF) and nanocrystals (CNC) present similar composition than paper but their exceptional properties in the nanometer scale confers a paper quality enhancement. However, some agglomeration problems in CNF and CNC through hydrogen bonding cause a lower improvement of mechanical properties of paper. Therefore, a better dispersion of both nanocelluloses can maximize their effect on paper properties, thus reducing the needed dose to get the same increment in tensile strength and then reducing material costs. To ease the implementation of these nanocelluloses in the production process of recycled paper, typically used operations of these industries have been used. Among them, those devoted to improve the homogeneous mixture of nanocellulose in the pulp suspension have been assessed. Firstly, pulping conditions were studied, including pulping time, temperature and need for soaking as variables. Secondly, some dispersing agents used in papermaking were considered, studying the effect of different types and doses. The highest tensile strength of paper was achieved by applying long pulping times (60 min), getting increments up to 30% with the use of soaking and polyacrylamide as retention system. However, with the use of a low dose of a dispersing agent (0.003%), tensile index can be still increased up to 20.6% avoiding these long times. This study can be of great interest of those researchers trying to implement the use of nanocelluloses as strength additive in papermaking. [ABSTRACT FROM AUTHOR]

Nanocomposite (NC) papers using bifunctional nanoparticles are prepared for 3D cell growth experiments. Cells show better affinity to NC papers than to paper itself and differentiate the chemical group on the external surface of the nanoparticles. Cells possess spherical shaped morphology and form agglomerates onto the (NC) papers like as observed by cell growth in 3D materials. Furthermore, the preparation of “Janus” paper and the differentiation of its two distinct faces by cells is presented. [ABSTRACT FROM AUTHOR]

Ground calcium carbonate (GCC) was modified with starch, sodium stearate, and sodium hexametaphosphate prior to the papermaking process. This paper is focused on the effect of shear on the modified GCC and considers the impact of adding modified GCC into paper. The coating efficiency of starch on GCC was investigated in terms of the sheartolerance of the agglomerated filler. Experimental results showed that the precipitation temperature and the amount of crosslinking agent, sodium hexametaphosphate, both were important relative to shear tolerance. Lower precipitation temperature was beneficial for the starch coating. Within a certain range, more sodium hexametaphosphate led to a stronger complex. The results showed that 1.5% (based on MGCC) of sodium hexametaphosphate and a precipitation temperature of 60 °C were the optimum conditions for shear tolerance. [ABSTRACT FROM AUTHOR]

Thermochemical heat storage materials for space heating applications such as, ZnSO4 offer high energy storage density, low cost and clean mean of long-term solar energy storage. Herein, we studied the ZnSO4 hydrated salt as potential heat storage material at low temperature and furthermore observed the impact of temperature and concentration on the dehydration/hydration process and enthalpy. The thermal behavior of ZnSO4•7H2O was investigated by applying various dehydration temperatures. The results showed that 85% of water loosed at 100 °C temperature, which released 699 J/g (1.37 GJ/m3) in the dehydration process. The hydration process of ZnSO4.7H2O at 100 °C recovered 541 J/g enthalpies, which delivered 1.1 GJ/m3. Similarly, the dehydration result obtained at 150 °C was the same as showed at 100 °C. However, the enthalpy of hydration was 20% less than prior. The XRD result showed that at higher temperatures agglomeration appeared followed by Van der Waals forces which affect the hydration rate. The result of good cyclability and larger water sorption performance of ZnSO4 make them a promising and suitable for heat storage in space heating application, which can be used as thermochemical heat storage material for thermal storage devices. [ABSTRACT FROM AUTHOR]

In the pulp and paper industry, during the manufacturing process, the agglomeration of pitch particles (composed of triglycerides, fatty acids, and esters) leads to the formation of black pitch deposits in the pulp and on machinery, which impacts on the process and pulp quality. Traditional methods of pitch prevention and treatment are no longer feasible due to environmental impact and cost. Consequently, there is a need for more efficient and environmentally friendly approaches. The application of lipolytic enzymes, such as lipases and esterases, could be the sustainable solution to this problem. Therefore, an understanding of their structure, mechanism, and sources are essential. In this report, we review the microbial sources for the different groups of lipolytic enzymes, the differences between lipases and esterases, and their potential applications in the pulping industry. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) can be used to improve the physical properties of paper. However, previous studies have showed that the effectiveness of this improvement is impaired by the agglomeration of the disintegrated BC fibers. Effective dispersion of BC fibers is important to their reinforcing effects to paper products, especially those made of recycled fibers. In this study, carboxymethyl cellulose, xylan, glucomannan, cationized starch, and polyethylene oxide were used to improve the dispersion of BC fibers. With dispersed BC fibers, the paper made of recycled fiber showed improved dry tensile strength. The best improvement in dry tensile index was 4.2 N·m/g or 12.7% up, which was obtained by adding BC fibers dispersed with glucomannan. Glucomannan had the highest adsorption onto BC fibers, i.e., 750 mg/g at 1000 mg/L concentration, leading to the best colloidal stability of BC fiber suspension that had no aggregation in 50 min at 0.1 weight ratio of glucomannan to BC. TEMPO-mediated oxidation of BC was effective in improving its colloidal stability, but not effective in improving the ability of BC fiber to enhance paper dry tensile index while the wet tensile index was improved from 0.89 N·m/g to 1.59 N·m/g, i.e., ~80% improvement. [ABSTRACT FROM AUTHOR]

Microstickies deposits on both paper machine and paper products when it agglomerates under step change in ionic strength, pH, temperature and chemical additives. These stickies increase the down time of the paper mill and decrease the quality of paper. The key property of microstickies is its smaller size, which leads to low removal efficiency and difficulties in measurement. Thus the increase of microstickies size help improve both removal efficiency and reduce measurement difficulty. In this paper, a new agglomeration technology based on electric field was investigated. The electric treatment could also increase the size of stickies particles by around 100 times. The synergetic effect between electric field treatment and detacky chemicals/dispersants, including polyvinyl alcohol, poly(diallylmethylammonium chloride) and lignosulfonate, was also studied. [ABSTRACT FROM AUTHOR]

Storm cells that evolve in Mesoscale Convective Systems (MCSs) can be recognised with the use of satellite images. In this study, Meteosat images are used for the early detection and monitoring of the evolution of storm cells associated with MCSs. The developed methodology is based on the estimation of the "Airmass" and "Convective storm" composites, at fifteen minutes intervals. The methodology was applied on a selected four-day case study in February 2013, when a depression was developed over Africa and moved across the Mediterranean resulting in deep convection along its trajectory and in an extreme weather event (heavy rainfall associated with severe flooding) at the wider urban agglomeration of Athens. The produced composites detect potential vorticity (PV) anomaly related to cyclogenesis and increase the potential to detect and monitor storm cells associated with natural hazards. [ABSTRACT FROM AUTHOR]

In this paper, the dispersion of Carbon nanomaterials (CNMs) in an electrolytic solution containing cations such as Ca2+, Al3+, Na+, and Mg2+ with different types of superplasticizers (Sika, Master Ease 3502, Prime DC, and Prime Flow) have been investigated. Further, the stabilized CNMs along with different superplasticizers (Sps) incorporated into the cementitious mortar and studied their mechanical strength. The influence of Sps on the stability of CNMs in an aqueous medium has been monitored by UV-Visible spectroscopy. The study concludes that Sika Sp was the best dispersant for the CNMs dispersion in an aqueous medium. The de-stability of the CNMs has followed this trend of the agglomerations in the electrolytic solution as Al3+>Ca2+>Mg2+>Na+. The Sika Sp has great dispersant properties as well as provides a homogeneous distribution of CNMs in a cementitious matrix which was supported by FE-SEM analysis. The addition of SIKA@PPC-GO (GO about 0.0015% by weight of cement) and SIKA@PPC-FCNTs (FCNTs about 0.0015% by weight of cement) results in enhancement of cement 11.67%, 8.73% for compressive and 26.35, 20.61% for tensile strength respectively, at the curing ages of 90 days. This investigation may provide advanced knowledge to predict the stability of CNMs in superplasticizer-based solutions. [ABSTRACT FROM AUTHOR]

Oncolytic Newcastle disease virus is a new type of cancer immunotherapy drug. This paper proposes a scheme for delivering oncolytic viruses using hydrogel microneedles. Gelatin methacryloyl (GelMA) was synthesized by chemical grafting, and GelMA microneedles encapsulating oncolytic Newcastle disease virus (NDV) were prepared by micro-molding and photocrosslinking. The release and expression of NDV were tested by immunofluorescence and hemagglutination experiments. The experiments proved that GelMA was successfully synthesized and had hydrogel characteristics. NDV was evenly dispersed in the allantoic fluid without agglomeration, showing a characteristic virus morphology. NDV particle size was 257.4 ± 1.4 nm, zeta potential was −13.8 ± 0.5 mV, virus titer TCID50 was 107.5/mL, and PFU was 2 × 107/mL, which had a selective killing effect on human liver cancer cells in a dose and time-dependent manner. The NDV@GelMA microneedles were arranged in an orderly cone array, with uniform height and complete needle shape. The distribution of virus-like particles was observed on the surface. GelMA microneedles could successfully penetrate 5% agarose gel and nude mouse skin. Optimal preparation conditions were freeze-drying. We successfully prepared GelMA hydrogel microneedles containing NDV, which could effectively encapsulate NDV but did not detect the release of NDV. [ABSTRACT FROM AUTHOR]

In the process of agricultural development in arid and semi-arid areas, the carbon fixation capacity of vegetation can be affected to different degrees, but research on its driving factors is lacking. Consequently, this paper focuses on the Weiku Oasis in Xinjiang as its research area, in which the carbon fixation capacity of vegetation is estimated with the chemical equation of a photochemical reaction, using methods such as linear system models and Geodetector to analyze the relationship between cropland expansion characteristics and the carbon fixation capacity of vegetation from 1990 to 2020. The influence of land-use changes on the space differentiation of carbon fixation was elucidated through a time series relationship, and the synergistic effects of nine influencing factors on the carbon fixation capacity during the process of vegetation changes were discussed. The results were as follows: (1) In the process of agricultural development, the proportions of cultivated land area and spatial agglomeration had significant negative correlations with carbon sequestration, and the significance was rising, but the effect of cultivated land area proportion was more significant. (2) Through temporal sequential cooperativity analysis, when other land-use types were converted into cultivated land, the carbon fixation capacity of vegetation suddenly and significantly decreased in the initial year of the transformation, but the effect of cultivated land reclamation on the carbon fixation capacity of vegetation did not have a significant time lag. Moreover, after a certain period of time, cultivated land can gradually recover part of its lost carbon fixation capacity. (3) Among the nine driving factors, potential evapotranspiration is the most prominent in explaining the carbon fixation capacity of vegetation. This single-factor pairwise interaction presents the relationship between bivariate enhancement and nonlinear enhancement. When terrain factors interact with other factors, the enhancement effect of the influence on the carbon fixation capacity of vegetation has an obvious promotion effect. However, the change in the carbon fixation capacity of vegetation is more significantly influenced by potential evapotranspiration and the interaction between the normalized difference vegetation index (NDVI) and other factors. This research is helpful to understanding the basic theories related to the change in the carbon fixation capacity of vegetation during the process of agricultural development in arid and semi-arid areas, as well as providing theoretical reference for ecological environment construction and sustainable development. [ABSTRACT FROM AUTHOR]

The paper presents the concept of a questionnaire survey of urban residents as well as competent institutions and organizations, the purpose of which is to identify the sources of odour nuisance and assess the extent of the problem. These studies and analysis are undertaken in a city with a significant industrial share, located in central Poland (Masovian Voivodeship). [ABSTRACT FROM AUTHOR]

In this paper, the performance of a high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) was modeled using literature data. The paper attempted to combine different sources from the literature to find trends in the degradation mechanisms of HT-PEMFCs. The model focused on the activation and ohmic losses. The activation losses were defined as a function of both Pt agglomeration and loss of catalyst material. The simulations revealed that the loss of electrochemical active surface area (ECSA) was a major contributor to the total voltage loss. The ohmic losses were defined as a function of changes of acid doping level in time. The loss of conductivity increased significantly on a percentage basis over time, but its impact on the overall voltage degradation was fairly low. It was found that the evaporation of phosphoric acid caused the ohmic overpotential to increase, especially at temperatures above 180 °C. Therefore, higher temperatures can lead to shorter lifetimes but increase the average power output over the lifetime of the fuel cell owing to a higher performance at higher temperatures. The lifetime prognosis was also made at different operating temperatures. It was shown that while the fuel cell performance increased linearly with increasing temperature at the beginning of its life, the voltage decay rate increased exponentially with an increasing temperature. Based on an analysis of the voltage decay rate and lifetime prognosis, the operating temperature range between 160 °C and 170 °C could be said to be optimal, as there was a significant increase in performance compared to lower operating temperatures without too much penalty in terms of lifetime. [ABSTRACT FROM AUTHOR]

This paper discusses the creation of a growth deal for North Wales (The North Wales Growth Deal – NWGD). North Wales is primarily a rural region within the UK, without a core-city or large metropolitan centre. The paper examines how this urban dynamic, fostered around a pushing of the agglomerative growth model out of the city-region, is being transferred largely across rural space and place in terms of how growth is envisioned and how policy is implemented. It contributes to regional studies knowledge by raising the importance of the non-metropolitan city-regional alternatives in the context of the (academic and policy) city-regional debate. [ABSTRACT FROM AUTHOR]

In response to pressures imposed on the energy sector, several countries in the Middle East-North Africa (MENA) region have committed to increasing the percentage of renewable energy to reach 15–50% of the energy supply by 2030. New governance models are required to conceptualise and guide the energy transition into a more sustainable direction. Therefore, this paper employed the transition management governance framework to answer the questions of who is governing the renewable energy transition in Palestine, and in what ways it is achieved. The analysis is based on three levels: strategic (problem structuring and envisioning), tactical (coalition building, developing transition agenda), and operational (mobilising actors and implementing experiments). Accordingly, key energy-related institutions are examined in terms of their visions, capacities and scope of influence using semi-structured interviews, roundtable discussions, and a survey. The conducted policy analysis suggests that the Palestinian energy sector started experiencing profound changes that affected all actors who had to adapt or transform to remain active, in addition to the rise of various multi-level actors. The analysis also shows that actors are more connected compared to the conventional energy system. Findings suggest that the spread of renewable technologies was not the outcome of only top–down schemes; instead, it is achieved throughout the collaboration of multi-level institutions and increasing reliance on horizontal-based governance networks. The paper uses examples to imply that it is possible to overcome the agglomeration of restrictions imposed on the Palestinian energy sector due to conflict if established regimes support governance networks and local-level initiatives. [ABSTRACT FROM AUTHOR]

This paper separates two mechanisms through which agglomeration increases average firm innovation: selection (less innovative firms being forced out of agglomerations) and true agglomeration (firms become more innovative). I apply a quantile regression to estimate the distribution of firm innovation and separate these two mechanisms. Linking a unique establishment-level dataset with the patent dataset in the state of Maryland for the period 2004–2013, I find that a 1-mile radius area with above-median employment concentration significantly encourages firm innovation. An average establishment that files for at least one patent during the study period increases citation-weighted patent applications by 31.2% to 31.5% in such employment centers. I also find evidence of selection: non-innovators are 1.3% less likely to survive in agglomerations. The coexistence of agglomeration and selection causes the result of an ordinary least squares regression to be upwardly biased. By eliminating the selection effect, this study more precisely estimates the agglomeration effect, which can be applied to cost–benefit and cost-effectiveness analyses of urban and industrial policies. [ABSTRACT FROM AUTHOR]

Since solid propellants can significantly increase the mobility, load, and range of missile weapons and equipment when used as a power source, energy performance is always the primary focus of solid propulsion technology development. This paper investigated differences in the agglomeration of aluminum (Al) and characteristics of the burning surface of nitrate ester plasticized polyether (NEPE) propellants and hydroxyl-terminated polybutadiene (HTPB) propellants. The experiments were conducted under a 0.1 MPa argon gas atmosphere using a high-speed camera combined with a telephoto microscope head (macro lens). In comparison with HTPB propellants, it was discovered that the agglomeration process of Al particle of NEPE propellants had two modes. Al aggregates exit the burning surface after growing into nearly spherical agglomerates in Mode A, which is comparable to HTPB propellants. Unique to NEPE propellants, Mode B is where the Al particles aggregate into massive coral-like structures. Three factors could account for this discrepancy. First, since NEPE propellants include less ammonium perchlorate (AP), the AP is less likely to form a pocket structure. It keeps the Al particles in a large "pocket" resembling the burning surface and provides advantages for their ability to aggregate. Second, NEPE propellants have a thicker molten layer on the burning surface. It has a capillary force impact on the Al particles on the burning surface and promotes interaction between Al particles. Finally, NEPE propellants create a clear skeleton layer on the burning surface that helps Al particles stay on the burning surface. A microscopic multi-flame combustion model was created to describe the makeup of the flame of NEPE propellants. It includes the AP unit flame, the CL-20-AP flame, the Al combustion flame, and the diffusion flame of the products of decomposition of each component. In this study, the existence of molten layer and skeleton layer on the burning surface of NEPE propellants was observed for the first time in experiments. It contributes to the understanding of the unique agglomeration behavior of aluminum particles of NEPE propellants and provides theoretical guidance for the directional regulation of aluminum particle agglomeration characteristics. [ABSTRACT FROM AUTHOR]

A better understanding of the changes in binder chemistry and microstructure triggered by aging is fundamental as it increases the cracking susceptibility of asphalt materials and reduces pavement durability. In this context, this paper presents the findings of a collaborative study that delves further into the alterations in binder chemistry, microstructure, and rheology of laboratory – and field-aged binders using innovative experimental and fundamental theory techniques. An increase in polarity leading to a shift in the apparent molecular weight distribution (AMWD) towards higher molecular weights, which implies molecular agglomerations, could be observed as a result of aging via Saturates, Aromatics, Resins, and Asphaltene Determinator (SAR-AD) and Size Exclusion Chromatography (SEC), respectively. As for the theoretical methods, the δ-method and Molecular Agglomeration Index (MAI) that estimate the AMWD and incidence of molecular agglomeration, respectively, show satisfactory relationship with the SAR-AD and SEC results. This reinforces the soundness of the δ-method and MAI. [ABSTRACT FROM AUTHOR]

Aluminum (Al) particles are commonly added to energetic materials including propellants, explosives and pyrotechnics to increase the overall energy density of the composite, but aluminum agglomeration on the combustion surface may lower the combustion efficiency of propellants, resulting in a loss in twophase flow. Therefore, it is necessary to understand the agglomeration mechanism of aluminum particles on the combustion surface. In this paper, a high-pressure sealed combustion chamber is constructed, and high-speed camera is used to capture the whole process of aluminum accumulation, aggregation and agglomeration on the combustion surface, and the secondary agglomeration process near the combustion surface. The microscopic morphology and chemical composition of the condensed combustion products (CCPs) are then studied by using scanning electron microscopy coupled with energy dispersive (SEM-EDS) method. Results show that there are three main types of condensed combustion products: small smoke oxide particles oxidized by aluminum vapor, usually less than 1 mm; typical agglomerates formed by the combustion of aluminum agglomerates; carbonized agglomerates that are widely distributed, usually formed by irregular movements of aluminum agglomerates. The particle size of condensed combustion products is measured by laser particle size meter. As the pressure increases from 0.5 MPa to 1.0 MPa in nitrogen, the mass average particle size of aluminum agglomerates decreases by 49.7%. As the ambient gas is changed from 0.5 MPa nitrogen to 0.5 MPa air, the mass average particle size of aluminum agglomerates decreases by 67.3%. Results show that as the ambient pressure increases, the higher oxygen content can improve combustion efficiency and reduce the average agglomeration size of aluminum particles. [ABSTRACT FROM AUTHOR]

Currently, undetectable damage to workers and factory products is caused by the large number of oily fine particles present in the industrial environment. Previous studies have shown that different intensities of sound waves can promote the coalescence of fine particles, and the combination of water vapor condensation can further enhance the effect of acoustic coalescence. However, the research on acoustic coalescence is not extensive enough at present, especially research on the mechanism of the coalescence and growth of oily fine particles under acoustic and water vapor complex fields, which is even less studied. This paper focused on summarizing domestic and foreign research results on the interaction mechanism of acoustic convergence on particles and the agglomeration and growth of particles under the action of acoustic convergence and combined water vapor condensation, so as to explore the technical path of using acoustic convergence and combined water vapor condensation to regulate the size of oily fine particles and improve the purification efficiency in industrial situations. This research has significant scientific significance and application value for industrial environmental control, pollutant emission control, and healthy environment construction. [ABSTRACT FROM AUTHOR]

The gas injection parameters such as temperature, pressure and duration during the in-situ pyrolysis of oil shale are important factors that affect the pore evolution and product release characteristics of oil shale. This paper takes Huadian oil shale as a sample, uses pressurized thermogravimetry and pressurized fluidized bed experimental device to explore the influence of temperature, pressure and time on the evolution of pore structure under high-pressure nitrogen injection conditions, and analyzes the influence mechanism of pore structure evolution on the release and kinetic behavior of volatile products. The results show that in the range of 623–673 K, the effective oil recovery of oil shale pyrolysis under high pressure increases from 30.5 to 96.0% with the extension of temperature and pyrolysis time, and the average activation energy is 346.8 kJ/mol, which is higher than the activation energy of 306.6 kJ/mol under normal pressure pyrolysis. Under high pressure, the release process of volatile products is inhibited, resulting in the intensification of the secondary reaction of products and the reduction of olefin content. In addition, the primary pores of kerogen are prone to coking reaction and collapse of plastic structure, so that some large pores become microporous structure, and the average pore size and specific surface area are reduced. [ABSTRACT FROM AUTHOR]

This work presents a novel approach for the growth of potassium sulfate (K2SO4) from supersaturated solutions by reaction-extractive crystallization in a fluidized-bed crystallizer (FBC), in which K2SO4 is transformed into potassium chloride and sulfuric acid based on a reactive extraction-crystallization process using triisooctylamine (TOA) in n-octanol as the extraction system. This paper uses the moment transformation method to solve the population balance equations of K2SO4 in the extractive crystallization process, and the crystallization kinetic parameters are obtained by nonlinear regression. The kinetic equations of crystal nucleation, growth, and agglomeration rate in the crystallization process of potassium sulfate are determined, and experiments verify the reliability of the kinetic parameters. The results show that in a specific range, higher supersaturation and fluidization rate are conducive to the nucleation, growth, and aggregation of K2SO4. Suspension density promotes crystal nucleation and growth but has the opposite effect on accumulation. At the same time, based on the constant calculation equation of particle number and the constant calculation equation of mass, the extraction crystallization coupling mathematical model of the crystal in the fluidization state is established. The effects of suspension density, Reynolds number, extraction rate, feeding rate, and extraction concentration on potassium sulfate's nucleation, growth, and aggregation rate were studied by combining model calculation with experimental research. A process coupling model of the potassium sulfate extraction crystallization process in a fluidized bed was proposed. The model agrees with the experimental results, which have specific guiding significance for industrial production. [ABSTRACT FROM AUTHOR]

The nano-sized metal oxides (MOs) as combustion catalysts have been widely employed in solid rocket propellants, but the functionality of these materials is greatly restricted owing to their agglomeration. The catalytic activity of MOs on nanoscale was found to be significantly improved by the incorporation of MOs with carbon nanomaterials, which normally act as carriers allowing for well-distribution of MOs. In this paper, the CuO and Fe2O3 nanoparticles were produced by hydrothermal method and the CuO@C and Fe2O3@C nanocomposites with a uniform structure have been fabricated by an in-situ growth of corresponding MOs on the porous activated carbon (pAC). The morphology of the prepared MOs nanoparticles and resultant pAC carried ones were characterized using scanning electron microscope. It has been shown that the CuO and Fe2O3 nanoparticles are tightly adhered and dispersed on the surface of pAC. Their catalytic effects on the thermal decomposition of hexogen (RDX) were analyzed using thermal analysis techniques. Results indicate that the thermal decomposition of RDX was considerably promoted in the presence of these catalysts, where the CuO@C and Fe2O3@C were found to be capable of lowering the Tp for RDX by 14.8 °C and 12.4 °C, respectively. In addition, the decomposition kinetics of RDX in the presence of these catalysts have been evaluated with the DTG and DSC experimental data, and results show that the CuO@C and Fe2O3@C were able to reduce the Ea of RDX decomposition by 39.8 kJ mol−1 and 50.7 kJ mol−1, which is suggestive of an enhanced decomposition process for RDX by addition of carbon-loaded catalysts. The TG-FTIR analysis indicates that, in the presence of CuO@C and Fe2O3@C, the gaseous products are dominated by N2O in RDX decomposition. [ABSTRACT FROM AUTHOR]

Particle transport is still an immense challenge in many processes today and affects both the operation and the consistency of the product quality, which is essential in the pharmaceutical industry, for example. Therefore, we developed a suspension correlation of particles in the crystallization process for a slug flow crystallizer in the field of small-scale continuous crystallization in this paper to predict and ensure a reproducible process and consistent product quality. Furthermore, the developed suspension correlation shall provide the possibility to perform mechanistic modeling of the agglomeration behavior depending on the operating parameters in the crystallization process. For this purpose, already existing dimensionless numbers were evaluated and modified employing force balances in order to predict the particle behavior in the liquid compartments in the slug flow crystallizer under different operating conditions and particle shapes of the substance system l-alanine/water using L-glutamic acid as impurity during crystallization. [ABSTRACT FROM AUTHOR]

Paper gives a review of the most important results of extensive and wide-ranging research program on R&D of fluidized bed combustion technology in the Laboratory for Thermal Engineering and Energy of the VINCA Institute of Nuclear Sciences. Paper presents detailed overview of R&D activities from the beginning in the second half of the 1970's up to present days. These activities encompass applied research achievements in the field of characterization of limestones and bed agglomeration and sintering and modeling of overall processes during fluidized bed combustion, all of which have facilitated the R&D of the fluidized bed combustion technology. Attention is also given to steady-state combustion testing of a wide-range of fuels (coals, liquid fuels, biomass, waste solid and liquid materials, etc.) in our fluidized bed combustor and development of original methodology for testing the suitability of fuels for fluidized bed combustion, as well as specific achievements in the area of technology application in Serbia. [ABSTRACT FROM AUTHOR]

This paper uses insights from new economic geography (NEG) to examine eight commodities that span the COVID-19 medical value chain from 2000 to 2020 based on the multilayer network approach. Such an approach is distinguished from single layer approaches by taking into consideration interlayer connections. Centrality measures are based on the HITs algorithm to identify dominant exporters (hubs) and importers (authorities). We further examine the determinants of the multilayer trade networks with a gravity model. Three results are reported. First, the core-periphery structure under NEG has weakened over time with the internationalization of production in certain Covid medical commodities (CMCs). Second, home market effect remains relatively strong over time reflecting the role of NEG's agglomeration economies in locations with large home market demand. Finally, countries that restricted certain CMCs (especially PPEs and masks) even as they simultaneously facilitated the imports of other CMCs saw a decrease in exports. [ABSTRACT FROM AUTHOR]

A large amount of wet-discharged fly ash has caused serious harm to the ecological environment, so the utilization of fly ash has received attention. This paper analyzes the formation of products of fly ash–lime system under the autoclave process by X-ray diffraction (XRD) analysis and thermogravimetric–differential thermal (TG-DSC) analysis. The hydrothermal reaction product generation was quantitatively analyzed using the hydrochloric acid selective dissolution method to quantify the degree of reaction of fly ash in the pressure evaporation specimens in combination with the reaction degree of lime in the autoclave specimens. The hydrothermal reaction products were calcined and hydrated, and the mineral composition of the calcined products and the mechanical and microstructure of the hydrated products were analyzed. The results show that hydrothermal reactions occur in the fly ash–lime pressure evaporation system to produce C2SH, C3AH6, C3ASH4, and other products. The optimum ratio of lime is 22%, and the appropriate autoclave parameter is 140 °C for 8 h. Under this condition, the reaction degree of fly ash is 15.39%, the reaction degree of CaO is 78.63%, and its f-CaO value is 4.93%. The formation of C2SH in the hydrothermal reaction ranged from 14.33% to 18.53%, and the formation of C3ASH4 ranged from 14.06% to 15.26%. The hydrothermal reaction products were calcined at 850 °C for 1.5 h to produce new gelling materials with gelling phases, such as C12A7, α'L-C2S, β-C2S, and C2AS. The compressive and flexural strengths of the new gelling materials reached 34.4 MPa and 6.4 MPa, respectively, at the age of 180 days. [ABSTRACT FROM AUTHOR]

In heterogeneous catalytic reactions, supported metal catalysts have attracted increasing attention for the environmental remediation and industrial manufacture due to their inherent catalytic capacity. However, leaching, agglomeration, and poisoning of active metal particles lead to catalyst deactivation, thereby limiting their applications. To avoid this, strategies to protect the active metals from such inactivating processes are major areas of research. Emerging encapsulation strategies, in which active species are coated by protective shells, have proven to be a powerful technology to enhance catalytic performance by creating a well-developed structure about the active catalytic sites. This review highlights the recent advances on preparation method and application of encapsulated catalysts since 2016. Building upon the traditional confinement effect, new categories and extended concepts of encapsulation are introduced. In parallel, effects of encapsulation structure on performance and key factors controlling the structure of encapsulated catalyst are discussed definitely in this review. Finally, future perspectives on opportunities and challenges for further research in the field are given at the end of this paper. [ABSTRACT FROM AUTHOR]

In order to study the adaptability of urban agglomeration transport supply and demand structure, and to provide the basis for decision-makers when optimizing the structure of transport supply and demand in urban agglomeration, this paper proposed and verified a structure equilibrium theory on the basis of entropy theory. Firstly, based on the analysis of the influencing factors, an urban agglomeration transport demand structure model was established using entropy theory. Secondly, according to the actual passenger and freight turnover of urban agglomeration, a transport supply structure model was proposed with entropy theory. Then, by comparing the two entropy models, the equilibrium state of an urban agglomeration transport structure was analyzed. Finally, HuBaoOr urban agglomeration was taken as an example to verify the science and effectiveness of this discriminant model. The research in this paper lays a theoretical foundation for the achievement of urban agglomeration transport equilibrium structure and for realizing the best economic benefits and social benefits. [ABSTRACT FROM AUTHOR]

In this paper, we report Tin Selenide (SnSe) nanoparticles preparation through co-precipitation method and characterised by UV–Vis spectroscopy, scanning electron microscopy, Fourier transforms infrared spectroscopy, X-ray diffraction, EDX spectrum, photovoltaic and Supercapacitor performance. XRD patterns indicate that the prepared SnSe nanoparticles exist in the orthorhombic phase. The SEM and TEM image show that nanoparticles exhibit spherical shapes with high agglomeration. The UV-Visible spectrum recorded in the range of 200–800 nm, show peaks at 260 nm, 300 nm, and 350 nm while direct energy bandgap lies between 1.4 eV and 1.8 eV and indirect energy bandgap lies between 1.5 eV to 1.6 eV. The obtained SnSe counter electrodes (CEs) showed good electrocatalytic activity in the redox reaction of the I−/I3−. The Dye-sensitised solar cells (DSSC) of SnSe with molar ratios (1:1), (2:1), and (3:1) as showed good photovoltaic performances in comparison to platinium (Pt) counter electrode (CE). The higher specific capacitance value 1335 F/g of SnSe (3:1) electrode compare to the SnSe (1:1) and (1:2) electrodes proves the stability of SnSe (3:1) for supercapacitor performance. [ABSTRACT FROM AUTHOR]

In This paper, butyl titanate and LiOH·H2O was used as titanium source and lithium source respectively. Li4Ti5O12 as battery negative material was prepared by sol-gel method. The effects of chelating agent (triethanolamine), raw material ratio, calcination temperature and calcination time on Li4Ti5O12 products were studied by single factor method. The experimental results show that The optimum synthetic conditions are as follows: the spinel Li4Ti5O12 with pure phase, uniform grain size, 100–200 nm particle size and no obvious agglomeration can be prepared under the conditions of molar ratio of lithium to titanium is 0.9–1.0, the calcination temperature can be 730–750 °C at 8 h. After assembled into CR2016 button cell, the first charge-discharge capacity of CR2016 button cell can reach 169 mAh/g at 0.1 C rate, which is very close to the theoretical value of 175 mAh/g. [ABSTRACT FROM AUTHOR]

Semiconductive shielding layer as an important part of high‐voltage cable, its performance directly affects the safe operation and the service life of the cable. Carbon black (CB) is the main conductive filler of shielding materials, and its type and concentration directly affect the performance of the shielding layer. In this paper, CB‐A with higher structure and CB‐B with lower structure were used as conductive fillers and EBA was chosen as the matrix resin to prepare the shielding materials. The CB concentrations of the shielding materials were 35, 45, and 55 phr. The influences of CB type and concentration on the physicochemical, electrical, thermal and mechanical properties of the shielding materials were investigated. The research shows that when the CB types are the same, the higher the concentration of CB, the more intensive the CB network in the shielding material, and the more serious the CB agglomeration phenomenon. With increasing CB concentration, shielding materials show a decreasing trend of volume resistivity, an increasing trend of thermal conductivity, and a decreasing trend of mechanical properties. When the CB concentration is the equal, the CB‐A has better dispersion in the matrix resin, CB‐A/EBA shielding material has lower volume resistivity and weaker PTC effect, CB‐A/EBA shielding material has higher thermal conductivity at low temperature and CB‐B/EBA shielding material has higher thermal conductivity at high temperature, CB‐A/EBA shielding material has better mechanical properties. A comprehensive comparison shows that CB‐A/EBA shielding material with a concentration of 45 phr has excellent overall performance, with volume resistivity of 15.3 and 68 Ω·cm at 25°C and 90°C, respectively. The thermal conductivity is 0.434 W/(m K) at room temperature and 0.536 W/(m K) at 90°C. The stress is 31.08 MPa and the strain is 570.2%. This work has important reference for the selection of conductive fillers and performance improvement of semiconductive shielding materials. [ABSTRACT FROM AUTHOR]

High temperature environment has many negative effects on the drilling fluid system. In order to avoid or delay these negative effects, phase change materials (PLMs) microcapsule technology was introduced into the high temperature drilling fluid system in this study to further improve the applicability of the high temperature resistant drilling fluid under extremely high temperature formation environment. The microcapsules circulate with drilling fluid, and PLMs melt endothermically at high temperature in deep formation and solidify exothermically at shallow formation. A PLMs microcapsule with solar salt (NaNO 3 : KNO 3 = 3:2) as core material and nano silica as shell material was prepared by sol-gel interfacial polymerization. The structure and properties of the microcapsules were characterized, the temperature-control performance of the microcapsule and its stability and compatibility with drilling fluid were evaluated. The results showed that the microcapsules were well encapsulated, and the single microcapsule particles were spherical, but there was a certain agglomeration phenomenon. The particle size distribution of microcapsules was concentrated in 4–16 µm, with a median particle size of 7.79 µm. The highest encapsulation rate was 60.6%, and the melting enthalpy was 68.48 J/g. The microcapsules had no obvious mass loss below 400 ℃ and had excellent thermal stability. It was proved that the microcapsules had good sealability, shear stability and cycling stability, with the enthalpy/mass retention rate all above 90%. The addition of microcapsules will not affect the basic properties of drilling fluid, and can reduce the peak temperature of high temperature drilling fluid. Different from existing researches, this paper uses a method that absorbs heat to slow down the heating rate of drilling fluid in the formation. This is a new idea, which is expected to be widely studied in the field of high temperature drilling fluids. [Display omitted] • PCM microcapsules were prepared to increase the applicability of high temperature drilling fluid. • PCM microcapsules had good morphology, suitable size, and excellent shear and cycling stability. • PCM microcapsules had good compatibility with water-based drilling fluid. • PCM microcapsules had perfect thermal stability and considerable temperature control effect. [ABSTRACT FROM AUTHOR]

The paper introduces a mathematical model based on the discrete element method, presenting the results of its application to simulate the movement of briquetted mass within the working chamber of the extruder. This model accounts for the adhesive interaction among particles within the mixture. The simulation results provide a qualitative and quantitative description of the displacement and compaction of the briquetted mass. They allow the flow structure to be visualized and the distribution of velocities and the moment on the screw axis during the extrusion process to be determined. Furthermore, a digital twin of the pug sealer–extruder unit was created through finite element modeling. The results obtained from this digital twin can be used to optimize the operational parameters of extrusion briquette equipment. In addition, by using the developed model, the process of mixing binder materials with a briquetted mixture at various volumes of the added binder was studied. [ABSTRACT FROM AUTHOR]

The paper presents a granulometric analysis of the size of particles of Aeroxide® P25 and P90 titanium oxides in the context of their retention in low-pressure membrane processes (microfiltration, ultrafiltration). Measurements of the particle size using a laser granulometer showed that the particle size of TiO2 Aeroxide® P25 dispersed in water is in the range from approx. 0.3 µm to approx. 150 µm. The particles with dimensions smaller than 1.0 µm constituted about 7.0%, and the largest particles, with dimensions above 30 µm, constituted about 0.9% of the volume of all the particles in the suspension, respectively. In the case of TiO2 Aeroxide® P90, a double curve of grain size distribution was observed. For the main curve, the particle size ranged from approx. 0.3 µm to approx. 18.7 µm. The particles with dimensions smaller than 1.0 µm constituted approx. 3.0% by volume of all particles in the sample. The second curve, which can be described as oversized/supersized grains, was comprised of particles ranging in size from about 21 to 170 µm, and they accounted approximately for 3.9% by volume of the total particles in the sample. The specific surface area for the samples was 0.56 m²/g for TiO2 P25 and 0.48 m²/g for TiO2 P90. It was found that the observed large particle sizes of titanium oxide particles in aqueous solutions may be the result of their agglomeration, which gives one hundred percent certainty that they will be retained by ultrafiltration and microfiltration membranes with pore sizes above 0.3 µm. [ABSTRACT FROM AUTHOR]

Hydrogen metallurgy is a technology that uses hydrogen instead of carbon as a reducing agent to reduce CO2 emissions. The use of hydrogen is conducive to promoting the sustainable development of the steel industry. In recent years, how to solve the sticking problem in hydrogen reduction fluidized ironmaking technology has received extensive attention. The reactor used in this paper is a fluidized bed with an inclined agitator. The effects of the agitation speed and the reduction temperature on the fluidization state of iron concentrate particles were researched by a single-factor experiment. The results depicted that adding an inclined agitator into the traditional fluidized bed can effectively reduce the sticking ratio and keep the iron concentrate particles fluidized during the reduction process. Thus, the reduction efficiency of iron concentrate particles is improved. The optimal agitation speed is 160 rpm, and the optimum reduction temperature is 1123 K. [ABSTRACT FROM AUTHOR]

Currently, nanotechnology is referred to be one of the attractive research sectors in several countries because of its vast potential and commercial impact. Nanotechnology includes the investigation, development, fabrication, and processing of structures and materials on a nanoscale in various fields of science, health care, agriculture, technology, and industries. As such, it has provided a steady restructuring of related technologies. The aim of this review is a critical analysis of the present phase of knowledge concerning the synthesis, application, and limitation of Ag/Bentonite and ZnO/Bentonite nanocomposites. In this review paper, more than 50 articles were reviewed on Ag/Bentonite and ZnO/Bentonite nanocomposites (NCs) along with their applications and using the clay as supporting materials for those metals in the reduction of agglomeration. Besides, a few of the groundbreaking applications of nanomaterials for different areas like in catalytic activity, photocatalytic activity, antibacterial activity, and wastewater treatments have been reviewed. Their synthesis methods and characterization tools are also discussed. From their synthesis methods, green synthesis was more efficient. Moreover, the unique characteristics and applications of those NCs, their challenges for their applications, especially their drawback has been discussed and implications has been drawn. So concerns have to be given about the transport, destiny, and transformation of those nanocomposites discharged into the environment. [ABSTRACT FROM AUTHOR]

Different current reasons, like global warming due to greenhouse gases and high energy prices, creates the necessity to make the heating systems in large cities more efficient. The present paper presents a real situation for an urban agglomeration, regarding the transition from a centralized heating system to a decentralized one. Two types of decentralized possibilities are discussed and analyzed taking into account especially the CO2 emissions, during several recent years. In this respect, a calculus of CO2 emissions from the former heating system, compared to the present heating systems is also presented and discussed. [ABSTRACT FROM AUTHOR]

In the present study, a new method for investigating the effect of aggregation on carbon nanotube (CNT) composites has been developed, in which two aggregation parameters are introduced based on a combination of the self-consistent scheme and the Mori-Tanaka method. This paper mainly analyzes the effect of CNT agglomeration on the effective elastic modulus of CNT/polymer composites, and a micromechanical model is proposed for the analysis. The regions with concentrated CNTs are assumed to be spherical in shape and are considered as the inclusions. The dispersive CNTs in the pristine matrix can form a fictitious matrix. The effective elastic properties of inclusions and composites composed of inclusions and fictitious matrix are determined. It is found that the effective modulus of composite changes with the variation of two aggregation parameters. Moreover, the agglomeration of CNTs reduces the elastic stiffness of composites and the uniformly dispersed CNTs enhance the reinforcement effect. [ABSTRACT FROM AUTHOR]

The photocatalysis technology is known for its cleanliness, safety, ease of operation, and low pollution levels. However, traditional photocatalysts still have certain limitations: (1) the mechanism of charge generation and transfer within the photocatalyst particles remains unclear; (2) serious agglomeration leads to low catalytic efficiency, poor catalytic effects, weak light absorption ability, and difficulty in reuse. In contrast, floatable catalysts have been extensively studied over the past decade due to their exceptional properties, such as stable structure, easy recovery, high efficiency, etc. The present review paper begins by providing a comprehensive review of floatable photocatalysts, followed by an analysis and summary of their photocatalytic systems ranging from macro-design structure to micro-nano structure. Additionally, this paper introduces novel design principles and methods for floatable photocatalysts (for example, double-layer structure and hot-cold-end design). Furthermore, recent advancements in floatable photocatalysts are discussed through case studies in areas such as photocatalytic synthesis, degradation, power generation, and hydrogen production. The high recovery rate, high activity, and high stability of floating photocatalysts significantly impact the field of photocatalysis. This review aims to provide guidance for early researchers while offering theoretical support for future preparation and optimization efforts related to practical photocatalysts. [Display omitted] • Floatable photocatalysts are promising and have been extensively studied due to their exceptional properties. • This review provides comprehensive summary and analysis of floatable photocatalysts. • This review introduces novel design principles and methods for floatable photocatalysts. [ABSTRACT FROM AUTHOR]

In recent years, a low-grade vanadiferous titanomagnetite concentrate (LVTC) produced in the northwest area of Liaoning has attracted more and more attention. However, it is difficult to recover and utilize valuable minerals such as iron, titanium, and vanadium, due to their special physical and chemical properties and complex mineral composition. Grinding and magnetic separation are two important operational units for recovering valuable metal components from vanadiferous titanomagnetite. Therefore, the grinding kinetics of the LVTC in northwestern Liaoning were first studied by means of grinding kinetics equations in this paper. The results show that the grinding process of LVTC is consistent with the grinding kinetics equation, and the sieve residues of particles approached a constant value after grinding for 30 min, resulting from equilibrium between the fragmentation and agglomeration processes. In addition, equivalent particle size (EPS) and specific surface area (SSA) were linearly proportional to the double logarithm of grinding time, and the correlation coefficients for fitted data by the Rosin–Rammler–Bennet (RRB) model were slightly higher than those by the Swebrec model, and could reflect the dispersibility and uniformity of particle size distribution (PSD) quantitatively. Then, the grinding products were separated by magnetic separation, and the influence of grinding conditions on the grade and recovery ratio of Fe and TiO2 in the LVTC was analyzed. As a result, grinding time has a significant impact on the recovery ratio and grade of Fe and TiO2 during the magnetic separation process, and the LVTC grinding duration is not as prolonged as it might be, as the optimal grinding time is 20 min. Titanomagnetite, ilmenite, and titanite are still the predominant phases in all magnetic separation products at optimal grinding time, but the intensity or content of these three minerals varies between magnetic separation products, and 232 kA/m magnetic field intensity has a higher separation efficiency than 134 kA/m magnetic field intensity. [ABSTRACT FROM AUTHOR]

As the display resolution has been rapidly increased, the pitch between two electrodes has been continuously decreased to less than $20~\mu \text{m}$ pitch. Therefore, fine-pitch interconnection technology has become very important in display technology. In our previous research results, anchoring polymer layer (APL) structure was successfully introduced into anisotropic conductive film (ACF) system to form fine pitch interconnection by suppressing the conductive particles movement during the ACF assembly. In general, the agglomerated conductive particles between two electrodes can cause short-circuit problems at ACF assembly. In this paper, the magnetic field was applied to the Ni-coated polymer conductive particles in the polyvinyl fluoride (PVDF) APL structure to disperse the conductive particles uniformly in the xy plane. Then the effects of the magnetic fields on the dispersion of the Ni-coated conductive particles in the PVDF APL structure and the characterization of fine-pitch chip-on-glass (COG) assembly using PVDF APL ACFs with magnetically dispersed conductive particles were investigated. By optimizing the magnetic fields on the PVDF APL structure, 80% dispersed particle rate was successfully obtained. After the ACF bonding process, the conductive particles capture rates and contact resistance properties of magnetically dispersed PVDF APL ACFs, and the PVDF APL ACFs with no magnetic field applied were investigated at 20- $\mu \text{m}$ -pitch COG applications. Both PVDF APL ACFs showed a similar capture rate of conductive particles and electrical insulation property at $20~\mu \text{m}$ pitch. The PVDF APL ACFs with no magnetic field applied showed 100% of insulation property at $20~\mu \text{m}$ , but short circuits at less than pitch. However, for less than 20- $\mu \text{m}$ pitch, only the PVDF APL ACFs with magnetically dispersed conductive particles showed 100% insulation circuit rate down to the 11- $\mu \text{m}$ pitch because the conductive particles were not agglomerated but existed as single particles, resulting in no electrical short between fine-pitch adjacent bumps. As a result, magnetically dispersed PVDF APL ACFs can be used as new ACF materials for ultrafine-pitch interconnection applications without any electrical short. [ABSTRACT FROM AUTHOR]

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In the present paper, a new approach for detonation nanodiamond (DND) deagglomeration is proposed. DND agglomerates of the size from 20 to 200 nm have been exposed to wet sonication assisted oxidative treatment with ozone under UV irradiation (Advanced Oxidation Process). Subsequent sonication and centrifugation gave a stable hydrosol of individual DND particles with negative zeta potential of −65 mV. The yield of the desired 4–5 nm fraction reached 33 wt%. Powder X-Ray Diffraction study showed no signs of DND crystalline core degradation, while the surface of particles was enriched significantly with carboxyl functional groups according to the data of Diffuse Reflectance Infrared Fourier Transform Spectroscopy, that gave boost to the stability of DND hydrosol. The approach provides relatively high yield of deagglomerated detonation nanodiamond without impact of high temperatures on the DND particles. It also allows avoiding gas phase processes sticking to wet-chemistry that could be useful for process scalability. [ABSTRACT FROM AUTHOR]

In this paper, the instability of a vertical fluid motion, or throughflow, is investigated in a horizontal bidisperse porous layer that is uniformly heated from below. By means of the order-1 Galerkin approximation method, the critical Darcy–Rayleigh number for the onset of steady instability is determined in closed form. The coincidence between the linear instability threshold and the global nonlinear stability threshold, in the energy norm, is shown. [ABSTRACT FROM AUTHOR]

Calcium carbonate in the form of finely ground limestone is a material that has found its application in a wide range of industries, in the chemical, rubber, agricultural, and paper industries, is used for desulfurization of boilers and other. In civil engineering, ground limestone is used for the production of building materials, plaster and mortar mixtures, as a filler in concrete mixtures, in road construction, and as an essential component of mastic asphalt. This paper deals with examining the modification of the properties of finely ground limestone by the tumbling agglomeration method. It has been shown that the components of concrete with a round grain have a positive effect on the pumping of concrete in comparison with an elongated grain or the rough surface of crushed stone. The experiments will be carried out on a granulation plate using a variety of granulation liquid. The agglomerates and their properties were compared with untreated finely ground limestone, with a focus on detecting changes in compressibility, density and particle size. The output of this paper is a description and graphical representation of the changes in the properties of ground limestone before and after the agglomeration process. [ABSTRACT FROM AUTHOR]