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Modern industry actively uses metal structural materials to create innovative devices and components. In order to prevent emergency situations in production, nondestructive testing methods are used to detect defects on the surface of the material being developed. Among the methods of nondestructive testing, one can highlight the method of luminescent magnetic flaw detection, which allows identifying defects on the surface and under the surface of the test sample with minimal effort. It is known that in some cases, the magnetic‐powder method cannot achieve the required sensitivity due to the shape and location of defects themselves or due to certain conditions of object operation. To increase the visibility and sensitivity, magnetic nano‐ and microparticles can be conjugated with the dyes. Iron oxide nanoparticles (Fe3O4, γ‐Fe2O3) can be used as such magnetic particles, since they are quite easy to obtain and have low toxicity, high chemical stability, and a wide variety of magnetic properties. To ensure fluorescence of magnetic particles, a wide variety of fluorescent dyes associated with such particles are used. The dyes can include morin, naphthalimide derivatives, as well as semiconductor quantum dots. This article provides a review of fluorescent composite micro‐ and nanoparticles based on xanthene dyes (rhodamine, fluorescein, and pyronine). Such dyes are economically available luminophores, have good binding to the surface of magnetic particles, and therefore can be suitable for luminescent magnetic flaw detection. This review article discusses methods for producing composite nano‐ and microparticles of iron oxides with xanthene dyes and provides prospects of using composite nano‐ and microparticles in nondestructive testing methods. [ABSTRACT FROM AUTHOR]

We present FexOy composite particles prepared by pulsed laser irradiation of α-Fe2O3 nanoparticles dispersed in ethyl acetate and irradiated using a laser beam in the ultraviolet range with a wavelength of 355 nm. The sizes of particles and composition were controlled by tuning the laser parameters, such as laser fluence and irradiation time. We showed the evolution of the composition through X-ray diffraction measurements. Reactive bond molecular dynamics simulation results show bond breaking/formation during the synthesizing process. We examined the magnetic properties of the particles and showed that coercivity can be changed by the composition of particles and by increasing or decreasing particle size. The choice of systems built of iron and iron oxides made it possible to introduce the exchange bias effect into a range of magnetic properties of synthesized particles. [ABSTRACT FROM AUTHOR]

This study presents the development of a hierarchical design concept for the synthesis of multi‐scale polymer particles with up to five levels of organization. The synthesis of core–shell microparticles containing nested sets of dispersed metal and polymer micro‐ and nanoparticles is achieved through in situ photopolymerization using a double co‐axial capillaries microfluidic device. The flow rates of the carrier, shell, and core phases are optimized to control particle size and result in stable core–shell particles with well‐dispersed three‐level composites in the shell matrix. The robustness and reversibility of these core–shell particles are demonstrated through five cycles of drying and re‐swelling, showing that the size and structure of core–shell particles remain unchanged. Additionally, the permeability and mobility of dye molecules within the shell matrix are tested and showed that different molecular weight dyes have different penetration times. This study highlights the potential of microfluidics as a powerful tool for the controlled and precise synthesis of complex structured materials and demonstrates the versatility and potential of these core–shell particles for sensing applications as particle‐based surface‐enhanced Raman scattering (SERS). [ABSTRACT FROM AUTHOR]

This work presents experimental studies for obtaining composite particles of Co3O4/aluminium oxides. The dependences of the influence of process temperature and time on the phase composition, adsorption properties, morphology, and dispersion composition of particles are revealed. Experimental studies were carried out in the temperature range T = 350–410 °C and time τ = 180–420 min. It has been revealed that metallic aluminium, depending on temperature and time, transforms into the forms γ−Al2O3,χ−Al2O3andα−Al2O3 in the processes of sub- and supercritical aqueous oxidation. Due to a rapid decrease in pressure and temperature to atmospheric values, nano-sized cobalt oxide particles are formed from a supercritical water solution, which are deposited on the porous aluminum oxide particle surface. The results obtained on an scanning electron microscopy (SEM) with an energy-dispersive spectrometer indicate the deposition of cobalt oxide nanoparticles on the aluminium oxide surface and the formation of composite particles.The abilities of water under sub- and supercritical conditions, such as high mass transfer characteristics, low dielectric constant, manifestation of catalytic properties and high diffusion rates, allow dissolved metal oxides to penetrate and precipitate in matrices with micro-, sub-micro and nano-sized pores. This proposed method in this work makes it possible to obtain composite particles with uniform impregnation of the entire porous matrix surface, with the given composition and given physical and chemical properties. The influence of thermodynamic parameters on the properties of sub- and supercritical water can be controlled by the composite particle characteristics.Thus, this method makes it possible to obtain composite particles in one stage. It is alternative method to traditional ones, that allows to avoid the use of organic solvents, high temperatures and additional stages of preparation and processing of materials.

ABSTRACTWe successfully prepared Hydroxyapatite/Zinc oxide (HAp/ZnO) composite particles with hexagonal plate-like shapes. The surface of the ZnO particles was treated with (3-aminopropyl)triethoxysilane (APTES) as a scaffold for the crystallization of HAp from the precursor solution. From the results of XRD measurements and SEM images of composite particles, formation of HAp on the ZnO particles was revealed. In addition, diffraction peaks associated with the (0 0 2) and (0 0 4) planes of HAp were clearly observed. They also revealed that the HAp/ZnO composite particles had a c-face orientation. Furthermore, element mapping analysis by EPMA showed that the elemental distributions of Ca, P and Zn of the composites were almost coincident. These results suggested that the formation of HAp occurred on the ZnO particles. In contrast, the ZnO particles without APTES treatment readily dissolved in the precursor solution and the diffused Zn2+ ions reacted with PO43- ions and Ca2+ ions to form CaZn2(PO4)2. APTES treatment of the ZnO surfaces appeared to prevent the dissolution of ZnO in the solution and induce the adsorption of anions such as phosphate on ZnO.

We successfully prepared Hydroxyapatite/Zinc oxide (HAp/ZnO) composite particles with hexagonal plate-like shapes. The surface of the ZnO particles was treated with (3-aminopropyl)triethoxysilane (APTES) as a scaffold for the crystallization of HAp from the precursor solution. From the results of XRD measurements and SEM images of composite particles, formation of HAp on the ZnO particles was revealed. In addition, diffraction peaks associated with the (0 0 2) and (0 0 4) planes of HAp were clearly observed. They also revealed that the HAp/ZnO composite particles had a c-face orientation. Furthermore, element mapping analysis by EPMA showed that the elemental distributions of Ca, P and Zn of the composites were almost coincident. These results suggested that the formation of HAp occurred on the ZnO particles. In contrast, the ZnO particles without APTES treatment readily dissolved in the precursor solution and the diffused Zn2+ ions reacted with PO43- ions and Ca2+ ions to form CaZn2(PO4)2. APTES treatment of the ZnO surfaces appeared to prevent the dissolution of ZnO in the solution and induce the adsorption of anions such as phosphate on ZnO. [ABSTRACT FROM AUTHOR]

Composite particles composed of raw minerals and polymers are promising adsorbents for wastewater treatment because they are based on readily available resources and can be easily separated from water. However, the highly crosslinked molecular networks make the internal structures inaccessible, significantly restricting their adsorption capacity. This work reports the development of a porous polyvinyl formal–Linze palygorskite composite fabricated via a polyvinyl acetal reaction using inorganic salts as porogens. The resulting pore structure provides well-developed molecule/ion-transfer paths, enabling the efficient utilization of active sites in the bulk phase and facilitating complete internal adsorption. The optimal sample, P-PVFM-LZ, which was prepared with 5% NaCl by weight relative to Linze palygorskite and subsequently washed to remove the NaCl porogen, exhibited a distinct pore structure with a 44.0% higher specific surface area and 8.6% higher porosity than the composite prepared without NaCl (PVFM-LZ). Correspondingly, the adsorption capacities of P-PVFM-LZ for methylene blue, crystal violet, Pb2+, Ni2+, ciprofloxacin, and tetracycline hydrochloride are enhanced by 140.61%, 76.71%, 50.00%, 154.86%, 86.77%, and 75.49%, respectively, compared to PVFM-LZ. Furthermore, P-PVFM-LZ demonstrates desirable regenerative adsorption performance, even after six adsorption–desorption cycles. The proposed pore-engineering strategy is considered versatile for designing and fabricating raw-mineral composite adsorbents for efficient wastewater treatment. The porous structure design by NaCl porogen greatly promotes the efficient utilization of adsorption sites in the bulk-phase of polyvinyl formal-low-grade natural Linze palygorskite composite particles. [Display omitted] • Porous structure in P-PVFM-LZ composite particles were developed by NaCl as a porogen. • The adsorption performance and mechanism were detailly investigated. • Porous structure promotes the efficient utilization of active sites in the bulk-phase. • The adsorption capacities for cationic dyes, heavy metals, and pharmaceuticals increased. [ABSTRACT FROM AUTHOR]

In the present study, zinc oxide-bioactive glass composite nanoparticles were synthesized through a sonochemical/sol-gel method. The results revealed that the composite nanoparticles consisted of zinc oxide (ZnO) cores (259 ± 9 nm) surrounded by a thin bioactive glass (BG) shell with 26 ± 3 nm thickness. The zinc oxide and zinc oxide-bioactive glass composite nanoparticles were electrophoretically deposited on the AZ31 substrate involving an intermediate oxide layer applied using plasma electrolytic oxidation. The composite nature of the zinc oxide-bioactive glass nanoparticles facilitated the application of lower voltages during electrophoretic deposition compared to simultaneous deposition of individual zinc oxide particles. Dopamine was used in the bath as a surfactant and polyethyleneimine as a binder to ensure complete adhesion between coating and substrate. Microscopic examinations confirmed more uniformity in the coatings constituted of composite nanoparticles. Electrochemical impedance spectroscopy in a phosphate-buffered saline solution revealed a significant improvement in barrier performance of the composite coatings compared to the zinc oxide coating. According to the short-term bioactivity evaluations in simulated body fluid, more Ca–P deposits were formed on the composite coating. Furthermore, the adhesion between the coating and substrate increased significantly in this coating, mainly due to the rough surface of the nanoparticles. [ABSTRACT FROM AUTHOR]

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

Powder hemostatic particles have no limitation on wound type and a wide application prospect in the treatment of wound hemostasis. In this study, bioactive glass-based membrane-like structure camouflage composite particles (MBG@BSA/CS) were prepared by Layer-by-layer (LBL) method to coat bovine serum albumin (BSA) and chitosan (CS) on the surface of the synthesized macroporous and mesoporous bioactive glass (MBG). The results showed that MBG@BSA/CS particles significantly improved the coagulation effect of MBG and could activated both endogenous and exogenous physiological coagulation pathways. MBG@BSA/CS had the excellent water absorption quality and could immediately release Ca2+ to participate in the coagulation pathway. The main hemostatic mechanism of MBG@BSA/CS was that the membrane-like of BSA/CS could form a fibrin network by aggregating erythrocytes and activating platelets, thus rapidly aggregating coagulation factors. In addition, MBG@BSA/CS particles had a significant hemostatic effect on surface bleeding (tail-amputation model) and internal bleeding (liver injury model) in SD rats, which could shorten the bleeding time and reduce the amount of blood loss effectively. This research work stated that the MBG-based membrane-like structure camouflage composite particles might be with the potential applications as a hemostasis biomaterial for the emergency bleeding.

Nearly 60 years ago, Weinberg suggested a criterion for particle "compositeness", which has acquired a new life with the discovery of new, exotic hadrons. His idea resonates with model-based intuition. I discuss the role it plays in the context of another of Weinberg's creations, the model-independent framework of effective field theories. [ABSTRACT FROM AUTHOR]

Natural clay possesses advantages such as low cost and high adsorption capacity, rendering it a promising adsorbent for wastewater treatment. In this work, low-grade Linze palygorskite (LZ), comprising 20.5% palygorskite, was utilized as a representative material to synthesize polyvinylformal-LZ (PVFM-LZ) composite particles through cross-linking polyvinyl alcohol (PVA) with formaldehyde. The raw material ratio of LZ and PVA was maintained at a high level of 20:1. Meanwhile, high-purity montmorillonite (Mt) and palygorskite (Pal) were employed as raw materials to prepare PVFM-Mt and PVFM-Pal using the same method, enabling comparative analysis with PVFM-LZ. PVFM-LZ exhibited a notable adsorption capacity of 101.92 mg·g−1 for methylene blue, which was comparable to that of PVFM-Mt and PVFM-Pal. What's more, owing to the tightly cross-linked network structure formed by PVFM, PVFM-LZ demonstrated minimal loss (2.53%) and swelling (8.0%) rates in water, facilitating easy separation and promoting recyclability. Even after six cycles, its adsorption efficiency remained above 85%. The structure, physicochemical properties and adsorption performance of the three composite particles were meticulously examined before and after adsorption. Kinetic, thermodynamic and isotherm adsorption models revealed that PVFM-LZ exhibited spontaneous surface-controlled monolayer adsorption behavior. The possible adsorption mechanisms included electrostatic interactions, hydrogen bonding, and intermolecular forces. This work may provide an experience for the adsorption application of low-grade natural clay in composite engineering. [Display omitted] • PVFM-LZ was obtained by polyvinyl acetal method with a raw material ratio of 20:1. • PVFM mesh supports its stable structure in water for recycle utilization. • Deep insight of adsorption property for MB comparing with PVFM-Mt and PVFM-Pal. • Ideas of the efficient use of low-grade nature clay for sewage treatment. [ABSTRACT FROM AUTHOR]

We synthesized Au nanoparticle (AuNP)/ZnO composite particles in presence of an anionic surfactant and evaluated their photocatalytic activity under visible-light irradiation. AuNPs synthesized from HAuCl4 in the presence of amylase and the precursor solutions of ZnO were mixed, followed by a hydrothermal process, to synthesize crystal face-controlled AuNP/ZnO composite particles. X-ray diffraction (XRD) patterns and ultraviolet-visible (UV-Vis) spectra confirmed the formation of AuNP/ZnO composite particles. Furthermore, different Au to Zn concentration ratios in the precursor solutions resulted in different amounts of AuNPs in the composite particles. In addition, the average size of the AuNP/ZnO composite particles decreased with increasing Au to Zn concentration ratio. We believe AuNPs act as the nuclei for ZnO particle formation. The photocatalytic activity of the AuNP/ZnO composite particles was evaluated by the photodegradation of methylene blue (MB) under visible-light irradiation. The photodegradation rate of MB was higher with AuNP/ZnO composite particles compared to that with the ZnO particles synthesized in the absence of AuNPs. The AuNP/ZnO composite particles exhibit photocatalytic activity under visible-light irradiation owing to the enhanced charge separation efficiency and the localized surface plasmon resonance effect. [ABSTRACT FROM AUTHOR]

This study reports on an interfacial design method of Cu-SiC composites by means of nano-diamond/SiC composite particles in meltinfiltration process. In the case of Cu-SiC composites fabricated by melt-infiltration process, reaction layers consisting of spherical carbon particles and CuSi solid-solution alloys were observed as SiC particles reacted with melt Cu. Formation of reaction layers is not appropriate to obtain the predesigned characteristics such as physical and mechanical properties of the Cu-SiC composites. To overcome this problem, nanodiamonds, which were chemically inert with Cu, were bonded to the surfaces of SiC particles by amorphous silica as a bond material in order to shield the SiC particles from reacting with melt Cu. It was found that this shielding method enabled us to disperse SiC particles homogeneously in the Cu matrix without reaction layers. This interfacial design based on the composite particles should be expected to be applied to a promising mass production technology of metal-matrix composites (MMCs) due to its short processing time and large amount of production for processing composite particles. [ABSTRACT FROM AUTHOR]

The development of new electromagnetic interference materials has attracted much attention in the information warfare. Herein, a novel KPA@ Fe 3 O 4 composite particle was synthesized via a microcrystalline co-precipitation method. X-ray diffractions, scanning electron microscopes and vibrating sample magnetometer measurements were used to characterize the products. The results indicated that the surface of the potassium picrate (KPA) crystals was covered by magnetic Fe 3 O 4 nanoparticles, and composite particles exhibited excellent magnetic properties. Furthermore, the thermal behavior of the composite particles was investigated by differential scanning calorimetry, which showed that the composite particles inherited the energetic property of pure KPA crystals when the mass fraction of magnetic component was 50%, or 65%. As for the composite particles with 75% magnetic component, the thermal stability of was poor. In addition, the magnetic directional aggregation performance of composite particles was analyzed by dynamic simulation, which moved toward the magnetic source. For the composite particles with 50% magnetic component, the maximum concentration was about 63 times of the initial concentration, and the peak velocity was 0.63 m sâˆ'1. With the mass fraction of magnetic component increasing to 65%, the concentration and velocity of the composite particles generally increased at the corresponding moment. As the mass fraction of magnetic component increased to 75%, the change of them was not obvious. Therefore, the composite particles with Fe 3 O 4 /KPA mass ratios of 65/35 had the best comprehensive properties. The excellent energetic and magnetic directional aggregation properties can allow the composites to be used in many potential applications in the information warfare. [ABSTRACT FROM AUTHOR]

Advanced functional materials require sophisticated control of particle characteristics. The bottom-up process has been extensively used to produce functional materials for controlling the particle properties of composite particles. We propose crystallization at liquid-liquid interfaces as an advanced particle formation method. This review introduces crystallization at a liquid-liquid interface based on several case studies used in various applications. Conventional crystallization has been generally used to produce crystals and particles with homogeneous particle properties. Liquid-liquid interfacial crystallization makes it possible to create composite particles with hetero-phase structures and interfaces. Liquid-liquid interfacial crystallization with an inkjet technique can control the droplet size accurately, and the shape and particle size distribution are successfully controlled in inorganic-organic composite particles. In addition, we succeed in creating organic-organic composite particles using the interfacial crystallization by an ultrasonic spray nozzle. The coating efficiency of organic particles on the particles is enhanced using the ultrasonic spray nozzle in comparison with anti-solvent crystallization. In this study, the fabrication of inorganic-organic composite particles using a coaxial tube reactor on the liquid-liquid interfacial crystallization is proven successful. These findings suggest that liquid-liquid interfacial crystallization is a promising means of efficiently producing composite particles because of their applicability to infusion in various processes.

The application of curcumin (Cur) in fat-free food is limited due to its poor water solubility, stability, and bioaccessibility. In this study, zein-gum arabic-tannic acid (zein-GA-TA) composite particles with high physical stability were fabricated to deliver Cur (ZGT-Cur). Their stability and in vitro release properties were also evaluated. The results showed that the thermal and photochemical stability of Cur was improved after loading into composite particles. Meanwhile, the retention rate of Cur in ZGT-Cur composite particles was enhanced compared with Z-Cur or ZG-Cur particles. Fourier transform infrared (FTIR) spectroscopy confirmed that the hydrogen bond within the particles was greatly enhanced after the addition of tannic acid (TA). The in vitro antioxidant activity of Cur in ZGT-Cur composite particles was higher in terms of 2,2'-azino-bis (ABTS) (93.64%) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) (50.41%) compared with Z-Cur or ZG-Cur particles. The bioaccessibility of Cur in ZGT-Cur composite particles was 8.97 times higher than that of free Cur. Therefore, the particles designed in this study will broaden the application of Cur in the food industry by improving its stability and bioaccessibility.

We develop a sequential flow process for the production of monodisperse poly (methyl methacrylate) (PMMA)/polystyrene (PS) composite particles through a soap-free emulsion polymerization of methyl methacrylate (MMA) using the first water-in-oil (W/O) slug flow and a subsequent seeded emulsion polymerization of styrene (St) using the second W/O slug flow. In this process, monodisperse PMMA seed particles are first formed in the dispersed aqueous phase of the first W/O slug flow. Subsequently, removal of the oil phase from the slug flow is achieved through a porous hydrophobic tubing, resulting in a single flow of the aqueous phase containing the seed particles. The aqueous phase is then mixed with an oil phase containing St monomer to form the second W/O slug flow. Finally, monodisperse PMMA/PS composite particles are obtained by a seeded emulsion polymerization of St using the second W/O slug flow. We compared the reaction performance between the slug flow and the batch processes in terms of particle diameter, monomer conversion, particle size distribution, and the number of particles in the system. We found that internal circulation flow within the slugs can enhance mass transfer efficiency between them during polymerization, which results in monodisperse PMMA/PS composite particles with a large particle diameter and a high monomer conversion in a short reaction time, compared to those prepared using the batch process. We believe that this sequential microflow process can be a versatile strategy to continuously produce monodisperse composite particles or core-shell particles in a short reaction time.

In order to solve the problem of photo-generated electron-hole separation which affects g-C3N4 photocatalytic acti-vity, Au/g-C3N4 composite particles are in situ prepared. The morphology, microstructure and composition of as-prepared Au/g-C3N4 composite particles were characterized by TEM, SEM, XRD, XPS and FTIR, the photoelectric property of the composite particles is also characterized by UV-vis DRS, PL and EIS, and the catalytic activities were examined using the reduction of 4-NP as a model reaction. The results show that the laminated g-C3N4 is hexagonal crystal, while the gold nanoparticles dispersing between the lamella of the g-C3N4 are face-centered cubic crystallites. The visible-light absorption and electron-hole separation efficiency of g-C3N4 matrix are improved by the introduction of gold nanoparticles. When the mass fraction of Au is 0.5%, the amount of substance ratio of sodium chloroaurate and sodium citrate is 1∶3, the Au/g-C3N4 composite demonstrates the best photocatalytic activity. The composite catalyst has strong visible light responsiveness and significantly higher catalytic activity than pure g-C3N4, which provides a theoretical basis for the synthesis of g-C3N4 photocatalyst with high photocatalytic activity.

POSS-coated wollastonite composite particles were prepared by the liquid phase mechano-chemical grinding of wollastonite and POSS powder together in the high pressure homogenizer [1, 2, 3, 4] for the first time. And then we prepare UV curable coatings of vinyl trimethoxy silane(VTMS) / butyl acrylate (BA) with different content of composite particles [5]. Nuclear magnetic resonance spectroscopy, scanning electron microscopy and infrared spectra were used to investigate the microstructures and morphologies of the composite. The properties of the coatings are tested by FTIR, SEM, water contact angles and so on. The results indicate that the POSS was successfully loaded on the surface of silica fume to prepare composite particles and when the addition of the composite particles is 12%, the water contact angle of the UV curable coating reaches 151.96∘, and the mechanical properties of the coating are also qualified.

Nearly 60 years ago, Weinberg suggested a criterion for particle “compositeness”, which has acquired a new life with the discovery of new, exotic hadrons. His idea resonates with model-based intuition. I discuss the role it plays in the context of another of Weinberg’s creations, the model-independent framework of effective field theories.

The results of a study of the microstructure evolution of pre-mechanically activated elementary powders based on the Ti-25Al-25Nb (at.%) compositions differing in the particle size of the aluminum (Al) component are presented. It was found that during the mechanical activation, most of the Al was dissolved in the Ti and Nb lattices by interpenetration with the formation of solid solutions (Ti, Al) and (Nb, Al). It has been established that an increase in temperature to 1400 °C, when sintering powder materials based on the Ti-Al-Nb system, leads to a sharp increase in the temperature of Al particles, as a result of the melting of which it is impossible to control the phase formation, which ultimately leads to the difficulty of obtaining the required product. It was determined that in the process of spark-plasma sintering of mechanically activated compositions, intermetallic compounds are formed based on phases ‒ α2, B2 and O, and with an increase in the sintering temperature, their morphology and distribution in the alloy volume change.

• A rotary ALD reactor is developed for scalable fabrication of powders. • Grams of high surface area TiO 2 /AC composites are synthesized by ALD. • The structure of the TiO 2 /AC composite can be precisely controlled. • ALD TiO 2 /AC composites are highly reactive in photo-degradation of organics. • Ultra small TiO 2 crystals are responsible for the excellent catalytic performance. A high surface area photo-catalytic composite material is synthesized by depositing thin films of titanium dioxide (TiO 2) on activated carbon (AC) particles using atomic layer deposition (ALD). A rotary ALD reactor is developed for scalable fabrication of powder and grams of the catalyst is prepared in each batch. The processes of TiO 2 ALD are monitored by mass spectrometry. Saturated ALD surface reactions are confirmed so that the entire surface of the AC support is covered by conformal coatings of TiO 2. For composites fabricated by 3 or more ALD cycles of TiO 2 , the amorphous oxide layers can be converted to crystalline films by high temperature annealing. The as-prepared TiO 2 /AC composites are highly reactive in photo-catalyzed degradation of methyl orange. The excellent catalytic performance is attributed to the abundant and uniformly dispersed active phase, formation of very active ultra small (<5 nm) TiO 2 crystals, and easy accessibility of the active sites. [ABSTRACT FROM AUTHOR]

Heat treatment is widely used in food industry. Proteins and polysaccharides as important natural polymers in food, under heat treatment, the interactions between them could mediate the conformation and functional properties of proteins. Thermally induced β‐lactoglobulin‐gum arabic complexes (β‐Lg‐GA) were fabricated, and the effect of heat treatment on physicochemical properties of the complexes was systematically investigated. The average particle size of β‐Lg‐GA complexes decreased with temperature increased, at 85°C, a smaller size of 273 nm was obtained. A saturated adsorption of GA was found when mass ratio of β‐Lg/GA was <1:2. At pH = 4.2–7.0, electrostatic attraction between β‐Lg and GA was low and a fairly constant turbidity was observed, the formed composite particles had good stability to the pH value. Through UV, fluorescence, and FTIR spectroscopy, it was found that formation of the nanoparticles relied on thermal denaturation and aggregation of protein, the electrostatic, hydrophobic, and hydrogen bonding interactions between β‐Lg and GA were also important. Scanning electron microscope further indicated β‐Lg and GA had good compatibility, and the complexes had a spherical core–shell structure at molecular level. In addition, these prepared natural nanoparticles by heat treatment show significantly higher encapsulation efficiency for (‐)‐epigallocatechin‐3‐gallate (EGCG) than that of unheated, thus could be used as a promising carrier for biologically active substances. [ABSTRACT FROM AUTHOR]

Next-generation composite Al-Mg-Zr fuels for bio/chem-agent defeat applications rely on intermetallic formation reactions to reduce ignition temperatures below melting point of Al. Scaling-up the ball-milling synthesis of these powders will require a detailed understanding of how milling parameters and powder composition impact the evolution of powder microstructure. In the present work, we explore the effect of milling duration on the size, microstructure, and properties of (Al-8Mg):3Zr, (Al-8Mg):Zr, 3(Al-8Mg):Zr and 4(Al-8Mg):Zr composite powders. We report compositionally dependent refinement of Zr inclusions in the Al-8Mg matrix that impacts ignition temperatures (T ig). For (Al-8Mg):3Zr and (Al-8Mg):Zr composite powders, T ig initially drops as milling time increases to 60 min and then either plateaus or rises at longer milling times. In contrast, T ig generally decreases over the full 90 min milling duration for the two Al-8Mg-rich compositions. Reductions in heterogeneity and average Zr inclusion size dominate the ignition behavior and lead to steady decreases in T ig. Unlabelled Image • Composite microstructure depends on the overall composition of the powder mixtures. • Increasing milling duration increases partial reaction between constituents. • The extent of milling induced intermixing is compositionally dependent. • Cold-welding influences composite morphology and internal microstructure. • Ignition sensitivity of composites depends on both composition and milling intensity. [ABSTRACT FROM AUTHOR]

The results of a study of the microstructure evolution of pre-mechanically activated elementary powders based on the Ti-25Al-25Nb (at.%) compositions differing in the particle size of the aluminum (Al) component are presented. It was found that during the mechanical activation, most of the Al was dissolved in the Ti and Nb lattices by interpenetration with the formation of solid solutions (Ti, Al) and (Nb, Al). It has been established that an increase in temperature to 1400 °C, when sintering powder materials based on the Ti-Al-Nb system, leads to a sharp increase in the temperature of Al particles, as a result of the melting of which it is impossible to control the phase formation, which ultimately leads to the difficulty of obtaining the required product. It was determined that in the process of sparkplasma sintering of mechanically activated compositions, intermetallic compounds are formed based on phases -- α2, B2 and O, and with an increase in the sintering temperature, their morphology and distribution in the alloy volume change. [ABSTRACT FROM AUTHOR]

Advanced functional materials require sophisticated control of particle characteristics. The bottom-up process has been extensively used to produce functional materials for controlling the particle properties of composite particles. We propose crystallization at liquid-liquid interfaces as an advanced particle formation method. This review introduces crystallization at a liquid-liquid interface based on several case studies used in various applications. Conventional crystallization has been generally used to produce crystals and particles with homogeneous particle properties. Liquid-liquid interfacial crystallization makes it possible to create composite particles with hetero-phase structures and interfaces. Liquid-liquid interfacial crystallization with an inkjet technique can control the droplet size accurately, and the shape and particle size distribution are successfully controlled in inorganic-organic composite particles. In addition, we succeed in creating organic-organic composite particles using the interfacial crystallization by an ultrasonic spray nozzle. The coating efficiency of organic particles on the particles is enhanced using the ultrasonic spray nozzle in comparison with anti-solvent crystallization. In this study, the fabrication of inorganic-organic composite particles using a coaxial tube reactor on the liquid-liquid interfacial crystallization is proven successful. These findings suggest that liquid-liquid interfacial crystallization is a promising means of efficiently producing composite particles because of their applicability to infusion in various processes. [ABSTRACT FROM AUTHOR]

In geotechnical and mining engineering, numerous particle matters are involved in scientific and technical problems. Recognition and quantification of the structure and distribution of force chain networks using photoelastic experiments, for instance, are significantly important in understanding the internal mechanism of mesoscopic mechanics and studying the macroscopic mechanical behavior. Based on the algorithm of the mean square value of color gradient (G2), the correlations of G2 with the contact force (F) of different sizes of round and square particles were established and combined with digital image processing technology. A method was proposed for identifying particles in images and distinguishing square particles from round ones, and force chain structures and force chain distributions were obtained in photoelastic images. Using fully mechanized caving mining as an example, the proposed method was verified, and it elaborated the formation and characterization of mining-induced stress in a top-coal caving mining face. The study shows that F monotonically increases with increased G2, and larger particle sizes correspond to a faster growth of F. The contact forces of singular particle distribute primarily between 0.5 and 1.5 times average contact force. Also, the average contact forces in square particles and Φ12 mm circular particles are higher and mainly occur in strong force chains, whereas average contact forces in Φ10 mm and Φ8 mm circular particles are lower and primarily occur in weak force chains. In top-coal caving mining, force chains in top-coal and overburden strata are mainly displayed in tree-like forms. Strong force chains, which extend in a vertical direction, transmit majority overburden loads, whereas lateral-developed weak force chains play a role in supporting strong force chains. In the vicinity of the top-coal outlets, because of the lateral movement of particles toward the mined area, the weak force chains in top coal disappear, resulting in the strong force chains becoming weaker or completely disappearing.

Core-shell composite particles (CPs) are the most preferred choice for direct compaction (DC), but their application in herbal tablets is limited. Hydroxypropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP) are usually employed as the shell materials, but there are few, if any, researches exploring the different effects of HPMC and PVP on the properties of herbal CPs. In this study, the CPs containing HPMC (CP X-H) and CPs containing PVP (CP X-P) were prepared based on herbal powders (X). Their physical properties were characterized comprehensively. The differences in properties between CP X-H and CP X-P were explored, and their mechanism analysis was also performed profoundly. The results demonstrated that (i) CP X-H and CP X-P exhibited similar flowability; (ii) CP X-H generally exhibited better compactibility, larger particle size, and more uniform particle size distribution, and lower bulk density, tap density, and hygroscopicity than CP X-P; (iii) compared with the tablets produced with CP X-P, ones with CP X-H exhibited similar weight variation (%), lower friability, and longer disintegration time. The mechanism analysis manifested that the differences in physical properties between HPMC and PVP were the important and fundamental factors, which led to the differences in structure and surface morphology of particles, and in fundamental properties of CPs. These findings are beneficial to the development of herbal core-shell CPs for DC. [ABSTRACT FROM AUTHOR]

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• TiO 2 @polyfluorene (PF) composite particles were first prepared by sol-gel method. • Photocatalytic degradation of organic dyes were evaluated under sunlight irradiation. • TiO 2 @PF exhibits excellent photocatalytic efficiency and reusability under sunlight. In the tetrabutyl titanate solution via a sol-gel method, the nano-TiO 2 @polyfluorene composite particles were successfully prepared from the polyfluorene particles which were obtained by grinding fluorene with FeCl 3 through the solid-state oxidative coupling reaction. The morphology and optical properties of the composite particles were characterized by scanning electronmicroscope, high resolution transmission electron microscopy, X-ray photo electron spectrometer, X-ray diffractometer, UV–visible diffuse reflectance spectroscopy, photoluminescence spectra and so on. The composite particles presented excellent photocatalytic activity on the degradation of triphenylmethane dyes, such as malachite green and rhodamine B under sunlight or under visible light. The photocatalytic reusability was investigated up to six successive cycles and the composite particles still retained their high activity of photodegradation ratio for malachite green. The mechanism of photocatalysis has been were discussed. The high surface area and effective photoinduced electrons and holes of TiO 2 @polyfluorene led to the enhanced photocatalytic activity. Consequently, the nano-TiO 2 @polyfluorene composite particles can be employed as an efficient photocatalyst to treat the organic pollutants. [ABSTRACT FROM AUTHOR]

The authors have modeled the one-stage synthesis of titania and silica composite nanoparticles in the working zone of a plasmachemical reactor by the chloride method based on separate oxidation of titanium and silicon tetrachlorides with pre-mixing of the reagents by bubbling. Within the framework of the developed synthesis model, the authors have obtained data on the size of the nuclei of the composite particles, the shell thickness, and the ratio of the number of shell-coated and uncoated particles. [ABSTRACT FROM AUTHOR]

Given the constraints on typical bond energies and the commonality of final products produced from combustion of C H N O based energetic materials, the possibilities for further increases in stored potential energy and thermodynamic performance from these classes of materials are limited. Thus, modulating the energy release to achieve efficiency and effectiveness for desired applications is of great value. Investigation of nanomaterials as energetic materials began more than twenty years ago with much of the interest to increase reaction rates and reduce sensitivity. During this period, research on energetic nanoparticles was devoted to reducing the loss of energy density with metallic materials due to the naturally occurring oxide passivating layer, managing their high surface area preventing high loadings in solids, minimizing particle-particle interactions making dispersion in the gas-phase difficult, and understanding combustion mechanisms. As an outcome, novel synthesis methods of producing nanocomposites, and new fields of applications, such as micro-pyrotechnics, have developed. Yet, the research community is only beginning to understand how to manipulate and build energetic materials at the nanoscale, and what designs are optimal for desired functions. Furthermore, recognizing the difficulties for increased energy density and reduced sensitivity, the development of multifunctional and smart nanoenergetic materials is currently being researched to enable control of energy release rates and material sensitivity on demand. This research is being advanced by assembly of nanoengineered energetic materials to bulk scales by additive manufacturing, the development and application of combustion diagnostics that resolve nanometer and micron scales, and ab initio quantum chemistry and molecular dynamics calculations. The challenges that have been confronted and the directions of continuing research on nanoenergetics are presented and discussed. [ABSTRACT FROM AUTHOR]

• Coarse particle flotation can be improved by increasing contact angles. • Contact angles of chalcopyrite increased to ∼150° using Super Collectors. • Loss of coarse particles in the froth phase is due to bubble coarsening. • Super Collectors increase flotation recoveries at lower retention times. With decreasing ore grades, the cost of mineral processing has been escalating due to the high costs associated with grinding larger volumes of ores for liberation. To minimize the embodied cost, mined ores are usually coarse ground for rougher flotation, in which much of the waste (or 'dead') rocks are removed before regrinding the rougher concentrate to obtain the final product. Thus, the feed to a rougher flotation bank frequently consists of coarse particles that are poorly liberated and, hence, are not hydrophobic enough to be collected by air bubbles in the pulp phase and survive the froth phase without being detached. In the present work, we explored the possibility of improving the flotation of composite particles using Super Collectors that can increase the water contact angles (θ) of the copper-bearing mineral grains well above 90°. The efficacy of this approach has been tested in laboratory flotation tests, followed by a series of simulations using a flotation model. The model has been derived from first principles using the surface forces in wetting films as kinetic parameters. The major input to the simulator was the liberation matrix (m ij) of a flotation feed and the various operating parameters. The simulations were carried out to obtain the grade vs. recovery curves for a low-grade (0.24 %Cu) porphyry copper ore feed with d 80 = 288 µm. The simulations were carried out using a Super Collector that can increase θ of the chalcopyrite grains to 150°. The grade vs. recovery curves obtained from the simulation showed that the Super Collector can substantially increase the recovery of composite particles over the case of using potassium amyl xanthate (PAX) as a collector at approximately 40 % shorter retention times. The simulation results also showed that Super Collectors help minimize bubble coarsening and hence contribute to improving the coarse particle recovery. [ABSTRACT FROM AUTHOR]

In this work, high-temperature pyrolysis was used to prepare both the core and shell of lantha-nide-doped UCNPs with lithium yttrium tetrafluoride (LiYF4) to enhance the green luminescence. Merocyanine 540 (MC540)-grafted magnetic nanoparticles were incorporated in the PD-L1 pep-tide-imprinted poly(ethylene-co-vinyl alcohol) particles, which were formed by precipitation in a non-solvent. UCNPs in the non-solvent bath were thus entrapped in the imprinted particles to generate composite nanoparticles for the targeting and photodynamic therapy of PD-L1 in tumor cells. Finally, the in vitro cytotoxicity of the nanoparticles in HepG2 human liver cancer cells was evaluated with the continuous administration of MC540/MNPs@MIPs/UCNPs under irradiation by an NIR laser. To understand the delivery of the UCNP-embedded molecularly imprinted pol-ymers, the intrinsic and extrinsic pathways were also investigated.

Quantum dots (QDs) have been widely applied in luminescent sources due to their strong optical characteristics. However, a moisture environment causes their quenching, leading to an inferior optical performance in commercial applications. In this study, based on the high moisture resistance of epoxy resin, a novel epoxy/QDs composite particle structure was proposed to solve this issue. Flexible luminescent films could be obtained by packaging composite particles in silicone resin, combining the hydrophobicity of epoxy resin and the flexibility of PDMS simultaneously. The photoluminescence and light extraction were improved due to the scattering properties of the structure of composite particles, which was caused by the refractive index mismatch between the epoxy and silicone resin. Compared to the QD/silicone film under similar lighting conditions, the proposed flexible film demonstrated increased light efficiency as well as high moisture stability. The results revealed that a light-emitting diode (LED) device using the composite particle flexible (CPF) structure obtained a 34.2% performance enhancement in luminous efficiency as well as a 32% improvement in color conversion efficiency compared to those of devices with QD/silicone film (QSF) structure. Furthermore, the CPF structure exhibited strong thermal and moisture stability against extreme ambient conditions of 85 °C and 85% relative humidity simultaneously. The normalized luminous flux degradation of devices embedded in CPF and QSF structures after aging for 118 h were ~20.2% and ~43.8%, respectively. The satisfactory performance of the CPF structure in terms of optical and moisture stability shows its great potential value in flexible commercial QD-based LED displays and lighting applications.

The main goal of this work was to assess if the Supercritical CO 2 -Assisted Spray Drying (SASD) is a competitive technology for the production of inhalable trehalose and leucine composite particles with advantageous properties and aerodynamic performance while ensuring a high process throughput and yield. For that purpose, a systematic Quality-by-Design approach using the design of experiments tool, followed by a statistical analysis were implemented. A full-factorial design was used to assess the impact of the static mixer pressure, inlet drying gas temperature and feed flowrate on the powder physical properties and in vitro aerodynamic performance. The powders were produced through SASD with yields up to 70%, while enabling the optimization of the overall throughput. Improved in-vitro aerodynamic performance was driven by the successful manipulation of the process parameters, namely by decreasing the feed flowrate and increasing the inlet drying temperature, yielding powders with fine particle fraction values up to 86%. Unlabelled Image • The suitability of SASD technology to produce inhalable particles was assessed. • A QbD approach using DoE tool followed by a statistical analysis was performed. • SASD technology produced small and uniform particles with enhanced performance. • SASD technology is a potential alternative to the Spray Drying technology. [ABSTRACT FROM AUTHOR]

The warming trend in the Arctic region is expected to cause drastic changes including permafrost degradation and vegetation shifts. We investigated the spatial distribution of ice content and stable isotopic compositions of water in near-surface permafrost down to a depth of 1 m in the Indigirka River lowlands of northeastern Siberia to examine how the permafrost conditions control vegetation and microtopography in the Taiga–Tundra boundary ecosystem. The gravimetric water content (GWC) in the frozen soil layer was significantly higher at microtopographically high elevations with growing larch trees (i.e., tree mounds) than at low elevations with wetland vegetation (i.e., wet areas). The observed ground ice (ice-rich layer) with a high GWC in the tree mounds suggests that the relatively elevated microtopography of the land surface, which was formed by frost heave, strongly affects the survival of larch trees. The isotopic composition of the ground ice indicated that equilibrium isotopic fractionation occurred during ice segregation at the tree mounds, which implies that the ice formed with sufficient time for the migration of unfrozen soil water to the freezing front. In contrast, the isotopic data for the wet areas indicated that rapid freezing occurred under relatively non-equilibrium conditions, implying that there was insufficient time for ice segregation to occur. The freezing rate of the tree mounds was slower than that of the wet areas due to the difference of such as soil moisture and snow cover depends on vegetation and microtopography. These results indicate that future changes in snow cover, soil moisture, and organic layer, which control underground thermal conductivity, will have significant impacts on the freezing environment of the ground ice at the Taiga–Tundra boundary in northeastern Siberia. Such changes in the freezing environment will then affect vegetation due to changes in the microtopography of the ground surface. [ABSTRACT FROM AUTHOR]

The origins of agriculture in Southwest Asia over 10,000 years ago and its subsequent spread into Europe during the Neolithic have been the focus of much archaeological research over the past several decades. Increasingly more sophisticated analytical techniques have allowed for better understanding of the complex interactions that occurred amongst humans, animals, and their environments during this transition. The Aegean Islands are critically situated where Anatolia and the mainland Greece meet, making the region pivotal for understanding the movement of the Neolithic into Europe. Located on the largest Turkish Aegean island of Gökçeada, the site of Uğurlu Höyük dates to the early Neolithic and has been the subject of ongoing excavations and research integrating a rigorous dating program with comprehensive zooarchaeological research. This paper focuses on the combination of bone collagen and tooth enamel stable isotope data with existing archaeological data to develop a fine-resolution picture of the spread of the Neolithic, particularly the importation and management of domestic fauna on Gökçeada, with broader relevance for understanding Aegean-Anatolian interactions. The stable isotope values from the fauna at Uğurlu have been used for both diachronic intrasite analyses and intersite comparisons between contemporaneous mainland sites. Integrating stable isotope and zooarchaeological datasets makes Uğurlu one of the first island sites to provide a comprehensive understanding of the geographic origin of Neolithic livestock populations and the timing of their spread from Anatolia into Europe during the process of Neolithization. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinase 2 (CDK2) is an important member of the CDK family exerting its most important function in the regulation of the cell cycle. It catalyzes the transfer of the gamma phosphate group from an ATP (adenosine triphosphate) molecule to a Serine/Threonine residue of a peptide substrate. Due to the importance of this enzyme, and protein kinases in general, a detailed understanding of the reaction mechanism is desired. Thus, in this work the phosphoryl transfer reaction catalyzed by CDK2 was revisited and studied by means of hybrid quantum mechanics/molecular mechanics (QM/MM) calculations. Our results suggest that the base-assisted mechanism is preferred over the substrate-assisted pathway when one Mg2+ is present in the active site, in agreement with a previous theoretical study. The base-assisted mechanism resulted to be dissociative, with a potential energy barrier of 14.3 kcal/mol, very close to the experimental derived value. An interesting feature of the mechanism is the proton transfer from Lys129 to the phosphoryl group at the second transition state, event that could be helping in neutralizing the charge on the phosphoryl group upon the absence of a second Mg2+ ion. Furthermore, important insights into the mechanisms in terms of bond order and charge analysis were provided. These descriptors helped to characterize the synchronicity of bond forming and breaking events, and to characterize charge transfer effects. Local interactions at the active site are key to modulate the charge distribution on the phosphoryl group and therefore alter its reactivity. [ABSTRACT FROM AUTHOR]

Imaging mass cytometry (IMC) is a technique allowing visualization and quantification of over 40 biological parameters in a single experiment with subcellular spatial resolution, however most IMC experiments are limited to endpoint analysis with antibodies and DNA stains. Small molecules containing tellurium are promising probes for IMC due to their cell permeability, synthetic versatility, and most importantly their application to sequential labelling with isotopologous probes (SLIP) experiments. SLIP experiments with tellurium-containing probes allow quantification of intracellular biology at multiple timepoints with IMC. Despite the promise of tellurium in IMC, there are unique challenges in image processing associated with tellurium IMC data. Here, we address some of these issues by demonstrating the removal of xenon background signal, combining channels to improve signal-to-noise ratio, and calculating isotope transmission efficiency biases. These developments add accuracy to the unique temporal resolution afforded by tellurium IMC probes. [ABSTRACT FROM AUTHOR]

Three individuals dating to the Great Migration Period (5th century CE) were discovered in a pit at the Hermanov vinograd site in Osijek, Croatia. We were inspired to study these individuals based on their unusual burial context as well as the identification of two different types of artificial cranial deformation in two of the individuals. We combine bioarchaeological analysis with radiographic imaging, stable isotopes analysis, and ancient DNA to analyze their dietary patterns, molecular sex, and genetic affinities in the context of the archaeological data and their bioarchaeological attributes. While all three individuals were adolescent males with skeletal evidence of severe malnutrition and similar diets, the most striking observation is that they had major differences in their genetic ancestry. Results of the genetic analyses of the nuclear ancient DNA data for these individuals indicate that the individual without artificial cranial deformation shows broadly West Eurasian associated-ancestry, the individual with tabular oblique-type has East Asian ancestry and the third individual with circular erect-type has Near Eastern associated-ancestry. Based on these results, we speculate that artificial cranial deformation type may have been a visual indicator membership in a specific cultural group, and that these groups were interacting intimately on the Pannonian Plain during the Migration Period. [ABSTRACT FROM AUTHOR]

Resource polymorphism—whereby ancestral generalist populations give rise to several specialised morphs along a resource gradient—is common where species colonise newly formed ecosystems. This phenomenon is particularly well documented in freshwater fish populations inhabiting postglacial lakes formed at the end of the last ice age. However, knowledge on how such differential exploitation of resources across contrasting habitats might be reflected in the biochemical compositions of diverging populations is still limited, though such patterns might be expected. Here, we aimed to assess how fatty acids (FA)—an important biochemical component of animal tissues—diverged across a polymorphic complex of European whitefish (Coregonus lavaretus) and their closely related monomorphic specialist congener vendace (Coregonus albula) inhabiting a series of six subarctic lakes in northern Fennoscandia. We also explored patterns of FA composition in whitefish's predators and invertebrate prey to assess how divergence in trophic ecology between whitefish morphs would relate to biochemical profiles of their key food web associates. Lastly, we assessed how information on trophic divergence provided by differential FA composition compared to evidence of resource polymorphism retrieved from more classical stomach content and stable isotopic (δ13C, δ15N) information. Examination of stomach contents provided high-resolution information on recently consumed prey, whereas stable isotopes indicated broad-scale patterns of benthic-pelagic resource use differentiation at different trophic levels. Linear discriminant analysis based on FA composition was substantially more successful in identifying whitefish morphs and their congener vendace as distinct groupings when compared to the other two methods. Three major FA (myristic acid, stearic acid, and eicosadienoic acid) proved particularly informative, both in delineating coregonid groups, and identifying patterns of pelagic-benthic feeding throughout the wider food web. Myristic acid (14:0) content and δ13C ratios in muscle tissue were positively correlated across fish taxa, and together provided the clearest segregation of fishes exploiting contrasting pelagic and benthic niches. In general, our findings highlight the potential of FA analysis for identifying resource polymorphism in animal populations where this phenomenon occurs, and suggest that this technique may provide greater resolution than more traditional methods typically used for this purpose. [ABSTRACT FROM AUTHOR]

The rich and long-lasting Nordic Bronze Age was dependent throughout on incoming flows of copper and tin. The crucial turning point for the development of the NBA can be pinpointed as the second phase of the Late Neolithic (LN II, c. 2000–1700 BC) precisely because the availability and use of metal increased markedly at this time. But the precise provenance of copper reaching Scandinavia in the early second millennium is still unclear and our knowledge about the driving force leading to the establishment of the Bronze Age in southern Scandinavia is fragmentary and incomplete. This study, drawing on a large data set of 210 samples representing almost 50% of all existing metal objects known from this period in Denmark, uses trace element (EDXRF) and isotope analyses (MC-ICP-MS) of copper-based artifacts in combination with substantial typological knowledge to profoundly illuminate the contact directions, networks and routes of the earliest metal supplies. It also presents the first investigation of local recycling or mixing of metals originating from different ore regions. Both continuity and change emerge clearly in the metal-trading networks of the Late Neolithic to the first Bronze Age period. Artifacts in LN II consist mainly of high-impurity copper (so-called fahlore type copper), with the clear exception of British imports. Targeted reuse of foreign artifacts in local production is demonstrated by the presence of British metal in local-style axes. The much smaller range of lead isotope ratios among locally crafted compared to imported artifacts is also likely due to mixing. In the latter half of Nordic LN II (1800–1700 BC), the first signs emerge of a new and distinct type of copper with low impurity levels, which gains enormously in importance later in NBA IA. [ABSTRACT FROM AUTHOR]

From an environmental perspective optimised dairy systems, which follow current regulations, still have low nitrogen (N) use efficiency, high N surplus (kg N ha-1) and enable ad-hoc delivery of direct and indirect reactive N losses to water and the atmosphere. The objective of the present study was to divide an intensive dairy farm into N attenuation capacity areas based on this ad-hoc delivery. Historical and current spatial and temporal multi-level datasets (stable isotope and dissolved gas) were combined and interpreted. Results showed that the farm had four distinct attenuation areas: high N attenuation: characterised by ammonium-N (NH4+-N) below 0.23 mg NH4+-N l-1 and nitrate (NO3--N) below 5.65 mg NO3--N l-1 in surface, drainage and groundwater, located on imperfectly to moderately-well drained soils with high denitrification potential and low nitrous oxide (N2O) emissions (av. 0.0032 mg N2O-N l-1); moderate N attenuation: characterised by low NO3--N concentration in drainage water but high N2O production (0.0317 mg N2O-N l-1) and denitrification potential lower than group 1 (av. δ15N-NO3-: 16.4‰, av. δ18O-NO3-: 9.2‰), on well to moderately drained soils; low N attenuation—area 1: characterised by high NO3--N (av. 6.90 mg NO3--N l-1) in drainage water from well to moderately-well drained soils, with low denitrification potential (av. δ15N-NO3-: 9.5‰, av. δ18O-NO3-: 5.9‰) and high N2O emissions (0.0319 mg N2O l-1); and low N attenuation—area 2: characterised by high NH4+-N (av. 3.93 mg NH4+-N l-1 and high N2O emissions (av. 0.0521 mg N2O l-1) from well to imperfectly drained soil. N loads on site should be moved away from low attenuation areas and emissions to air and water should be assessed. [ABSTRACT FROM AUTHOR]

Knowing what animals eat is fundamental to our ability to understand and manage biodiversity and ecosystems, but researchers often must rely on indirect methods to infer trophic position and food intake. Using an approach that combines evidence from stable isotope analysis and DNA metabarcoding, we assessed the diet and trophic position of Anthene usamba butterflies, for which there are no known direct observations of larval feeding. An earlier study that analyzed adults rather than caterpillars of A. usamba inferred that this butterfly was aphytophagous, but we found that the larval guts of A. usamba and two known herbivorous lycaenid species contain chloroplast 16S sequences. Moreover, chloroplast barcoding revealed high sequence similarity between chloroplasts found in A. usamba guts and the chloroplasts of the Vachellia drepanolobium trees on which the caterpillars live. Stable isotope analysis provided further evidence that A. usamba caterpillars feed on V. drepanolobium, and the possibilities of strict herbivory versus limited omnivory in this species are discussed. These results highlight the importance of combining multiple approaches and considering ontogeny when using stable isotopes to infer trophic ecology where direct observations are difficult or impossible. [ABSTRACT FROM AUTHOR]