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Stabilization mechanisms of partially premixed H 2 /air flames on a coaxial dual swirl injector are investigated at atmospheric conditions. Hydrogen is injected through a central duct, and the air by the outer annular channel. Both channels are swirled and two stabilization modes are observed depending on the geometrical configuration of the injector and on the operating conditions. In certain regimes, the H 2 /air flame stabilizes on the injector lips as a diffusion flame. For other operating conditions, the flame is lifted from the injector and burns mainly in partially premixed regime leading to limited NOx emissions. PIV measurements in cold flow conditions and direct observations of the flame indicate that the flame stabilization mode is mainly controlled by the inner hydrogen swirl level, the injector recess and the hydrogen velocity. For a given air flowrate, a minimum hydrogen velocity to lift the flame is determined for each combination of inner swirl level and injector recess. Assuming the flame close to the injector lips behaves like an edge flame, a model for flame stabilization based on the triple flame speed and the location of the stoichiometric mixture fraction line is built. According to this model, the flame is anchored to the injector if the triple flame can propagate to the inner injector lips, i.e., if the velocity along the stoichiometric line is lower than the triple flame speed. The model is tested using hydrogen diluted with argon and air diluted with nitrogen. Two cases producing predicted opposite trends are verified. First, the stoichiometric line is moved in the direction of lower velocity zone keeping the triple flame speed constant in order to anchor a lifted flame. Next, the stoichiometric line is kept constant and the triple flame speed is reduced in order to lift an anchored flame. The mechanisms driving flame stabilization are discussed. [ABSTRACT FROM AUTHOR]

Relationships between soil fractions (their mass or carbon (C)) and soil organic carbon (SOC) have been used to develop central ideas in SOC research. However, few attempts have been made to quantify the relationship between SOC and all soil fractions, despite the potential for such an effort to address SOC stabilization processes. We identified 41 published studies that used diverse management techniques to cause a change in SOC concentration and disrupted soil into macroaggregates (>250 μm), free microaggregates (53–250 μm) and free silt + clay (<53 μm), subsequently disrupting macroaggregates into constituent fractions (coarse particulate organic matter [cPOM] > 250 μm, occluded microaggregates, and occluded silt + clay). We used linear hierarchical models to quantify relationships between mass, C concentration and total C of fractions and SOC. Soil mass redistribution toward macroaggregates was associated with SOC accumulation, however total microaggregate mass (free + occluded) did not increase with macroaggregate mass, as would be expected given de novo microaggregate formation within macroaggregates. Instead, high SOC soils exhibited a greater percent of total microaggregates occluded in macroaggregates. Occlusion in macroaggregates was also associated with increased C concentrations of microaggregates (35% higher, SE = 3.2) and silt + clay (30% higher, SE = 3.9) relative to their free counterparts. Taken together, these relationships suggest reduced macroaggregate turnover promotes SOC accumulation via the stabilization of C into occluded fractions. Rates of SOC increase with silt + clay C concentrations failed to increase with mean site-level SOC concentration, indicating of the studied soils (median SOC concentration = 14 g kg−1; max 68), SOC accumulation appears unlikely to be limited by C storage capacity in the silt + clay fraction. For each unit SOC gain, macroaggregates accounted for 83% (95% CI = 74, 91), and occluded microaggregates for 43% (95% CI = 33, 52), consistent relationships that have potential to be used as benchmarks for fraction-based SOC models. Image 1 • We quantitatively reviewed 41 studies reporting macroaggregate-occluded fractions. • SOC increase was associated with gains in macroaggregate mass. • Macroaggregate-occlusion increased C concentration of microaggregates, silt + clay. • Macroaggregates may enable stabilization of POM to microaggregates, silt + clay. • 83% of SOC accumulated in macroaggregates; 43% occurred in occluded microaggregates. [ABSTRACT FROM AUTHOR]

Abstract Trehalose has been proven to be able to protect the membrane from being damaged by dehydration. Since dehydration is accompanied by large mechanical stress, it is meaningful to study the effect of trehalose on the membrane subject to lateral stress for understanding its protective mechanism. In present work, molecular simulations were performed on the POPC bilayers with different amount of trehalose under lateral pressure and tension. The results indicate that trehalose invariably induces increase in the area per lipid A xy and decrease in bilayer thickness h z and ordering degree | S CD |, which mean improved structure of membrane. However, the main roles trehalose plays are slightly different in stabilizing compressed and expanded membrane. Under tensile stress, the water replacement effect plays a leading role. Trehalose reaches as deep as water into the bilayer. Hydrogen bonds (H-bonds) forming between trehalose and lipid compensate the reduction of water-lipid H-bonds. More trehalose will replace more water to form H-bonds with lipid and help to hold the structure together through abundant H-bond bridges of various patterns. Under lateral pressure, the replacement of water is limited since trehalose only interacts with the bilayer surface zone. The sum of water-lipid (W-L) and trehalose-lipid (T-L) H-bond reduces upon addition of trehalose. Nevertheless, the penetration depth of water increases in the presence of trehalose while W L H-bonds become less. At the same time, W L H-bonds lifetime is significantly extended. These facts suggest that water forming H-bonds with phosphate and carbonyl oxygen and locating in bilayer interior is trapped by trehalose which is closer to surface and has longer H-bonds lifetime. It can be speculated that the residual water maintains the effective hydration level and the low ordering degree of membrane. This effect is similar to Water entrapment which takes place in the stabilization of protein by trehalose. Moreover, the presence of trehalose increases the viscidity of the system and makes it easy to vitrify. The membrane becomes stiffer and has more resistance to deformation from the perspective of K a. The vitrification mechanism is not excluded whether the membrane is compressed or stretched. Our findings could provide some insights in the design of protecting agents and processes. Highlights • POPC bilayers with varied trehalose content under lateral pressure and tension were modeled. • The bilayer structure is improved by trehalose whether compressed or stretched. • Under tensile stress, the main stabilization mechanism is water replacement effect. • Under lateral pressure, the water entrapment starts to take place. • The vitrification effect is not excluded under lateral pressure or tension. [ABSTRACT FROM AUTHOR]

An experimental study on the influence of porosity and hydrogen enrichment on the stabilization of premixed CH 4 -Air flames in Porous Media Burners (PMBs) is presented. Flame stabilization is analyzed via direct flame front tracking, which is made possible by a novel experimental apparatus. The use of additive manufacturing for computer-generated topologies allows making optically-accessible PMBs featuring see-through directions. This methodology also enables topology tailoring which is here exploited to study the influence of porosity on the performance of the burner. Flame front tracking reveals a different stabilization trend in highly H 2 -enriched flames. A comparison with a theoretical model is used to remove the effect of preheating and focus on other fuel properties. This suggests a flame-speed enhancement mechanism driven by Lewis number effects in Le < 1 mixtures. Together with recent 3D Direct Numerical Simulations, these results provide evidence that preferential diffusion effects are key in the stabilization of flames in PMBs. These phenomena, not considered in state-of-the art 1D-Volume Averaged Models, remain crucial for the design of efficient PMB using hydrogen as a fuel. [ABSTRACT FROM AUTHOR]

Trehalose and has been proven to be able to stabilize the native structure of biological system in extreme environments and widely used in cryopreservation. To understand the underlying mechanism of this stabilization effect, it is helpful to study the microscopic changes of membrane in the presence of varying amounts of trehalose upon rapid heating. In present work, molecular simulations were performed on the water/trehalose/POPC systems with different compositions. The results indicate that the stabilization of POPC membrane is greatly influenced by the content of trehalose as well as water. At a certain temperature, POPC membrane can be laterally expanded and transversely compressed upon addition of water or trehalose. The effective hydration level of bilayer is rising with the water or trehalose content increasing. The order degree of bilayer is almost insensitive to water content while it shows negative dependence on trehalose content, especially at lower temperature. On the other hand, as the temperature rises from 303 K to 373 K, the inclusion of trehalose significantly narrow the gap before and after heating for above parameters and this effect is more pronounced at higher trehalose content. With trehalose increasing from 0 to 256, the relative variation upon heating reduces by approximately 46.6% for area per lipid and 50.4% for bilayer thickness. That means other than improving the membrane structure at a certain temperature, trehalose also protects it from the injury due to structure change upon abrupt temperature variation. Further more, the essential mechanism is known as the slow mobility and strong hydrogen bonding (H-bonding) ability of trehalose. Compared with other cryoprotectants such as ethanol, trehalose dramatically slow down the movement of water, POPC and itself through H-bonds with longer lifetime between these molecules. Our findings could provide some insights in the design of protecting agents and processes. [ABSTRACT FROM AUTHOR]

Plant roots contribute substantially to the formation of stable soil organic matter (SOM), and there is evidence that species differ in their contribution to SOM stabilization. However, it remains unclear what specific root traits contribute to the three SOM stabilization mechanisms: recalcitrance against decomposition, occlusion in soil aggregates and interaction with soil minerals and metals. This is likely because research is highly fragmented and hampered by disciplinary barriers. By reviewing both plant functional ecology and soil science literature, we identified 18 different traits: architectural, morphological, physiological, symbiotic and chemical root characteristics, influencing the three SOM stabilization mechanisms. We found that traits increasing root recalcitrance promote short term stabilization by slowing decomposition, but that traits reducing recalcitrance contribute to long term stabilization by reaction of microbial products with mineral surfaces. Root length density, mycorrhizal association and rhizodeposition contribute to microaggregation. These and other traits, such as hemicellulose, soluble compounds, and high root branching index, favor macroaggregation. For stabilization by minerals and metals, those root traits promoting higher microbial activity: root nitrogen, hemicellulose and soluble compound concentrations are fundamental, while polyphenols, and litter Al and Mn also contribute to complexification and stabilization. Root depth distribution is the most important trait to control root C storage and stabilization in the subsoil; once roots have reached deeper soil layers, other traits, such as rhizodeposition and root chemistry, influence interaction with minerals and metals. Both mycorrhizal presence and root suberin promote SOC stabilization by means of all three mechanisms, indicating that these are important targets for continued work. Surprisingly, morphological traits commonly measured, namely specific root length and root diameter, poorly relate to stabilization mechanisms. Alternative traits such as chemical composition of the different root orders, root apex characteristics, quantity and quality of rhizodeposits as well as mycorrhizal fungal traits, should be further investigated. For future research, this review highlights the need to evaluate root decomposition and root-C stabilization concomitantly over the long-term, considering simultaneously root litter quality, estimated by root traits, the microbial products and properties of the soil matrix. The information accrued in this review can be used to evaluate the potential of plant species and cultivars to promote SOM stabilization, based on their root traits. [ABSTRACT FROM AUTHOR]

In this work, three methods were used for preparation of the emulsion. The mean particle diameter, ζ-potential, microstructure and stability of the emulsions coated by ovalbumin (OVA) and gum arabic (GA) were evaluated. The complexes (OVA/GA) and multilayer (OVA-GA) emulsions showed smaller droplet diameter (about 330 nm) above pH 3.3 and had a relatively good storage stability compared to the multilayer (GA-OVA) emulsion. Meanwhile, different stabilization mechanisms were identified. In the complexes (OVA/GA) emulsions, the OVA and GA formed complexes firstly that created an interface layer on the surface of the droplets. For the multilayer (OVA-GA) emulsion, the OVA adsorbed on the surface of the droplets, and then GA formed a double-layer structure by electrostatic interaction between the GA and the OVA. The multilayer (GA-OVA) emulsions showed a larger mean particle diameter due to the poor adsorption capacity of the GA compared with OVA. All emulsions revealed good thermal stability and no obvious change was observed. The experimental results demonstrated that the OVA/GA complexes could be used to prepare stable emulsion structures, which may be useful in the beverage industry. [ABSTRACT FROM AUTHOR]

The aim of this research was to perform a new evaluation of stabilizers dedicated to ethylene-norbornene copolymer (EN). The aging and stabilization processes of the EN polymer filled with natural (xanthone, naringenin) or synthetic (Rianox 626, Rianox 1726, Rianox 3114) antioxidants with different chemical structure were thoroughly analyzed and the suitability of the methods described in the literature to study these processes was assessed. EN is successfully used in optics, electronics or packaging sectors, but like any other organic material, it will degrade under the influence of environmental factors. The EN films were subjected to thermo- and photooxidation for 150, 300, 450, and 600 h. We observed that all composites exhibited an excellent resistance to thermo-oxidation, but as expected, much greater differences were noted after exposure to ultraviolet radiation. The performed tests: thermal analysis, FTIR spectroscopy, contact angles determination, color change measurements, static and dynamical mechanical tests proved the high effectiveness of the used antioxidants for the EN stabilization. However, in the case of the EN-xanthone sample, during the FTIR analysis, a higher value of the carbonyl index in comparison with the reference EN was obtained, and a greater change in the glass transition temperature (T g) compared to the other used stabilizers was observed. These changes could be caused by xanthone oxidation on the polymer surface and its plasticization because of aging, as evidenced by the increased T g value. In addition, we also discussed possible stabilization mechanisms of EN through the use of selected antioxidants. Interestingly, based on the obtained results, Rianox 626 containing phosphite groups in its structure turned out to be the most effective stabilizer for the ethylene-norbornene copolymer, even though it is a secondary antioxidant. It can therefore be suggested that the propagation stage plays a leading role in the degradation of this polymer, in which antioxidants decompose hydroperoxides. In the case of Rianox 626, phosphite groups reacted with hydroperoxides, thus creating the phosphate form of this stabilizer and alcohols, which are more stable and non-radical products. [Display omitted] • Polymer products based on ethylene-norbornene copolymer show high thermal resistance. • Natural stabilizers of plant origin can be a green alternative to synthetic antioxidants. • Chemical structure of antioxidant can affect the aging process of the polymer. • Rianox 626 is a highly effective stabilizer dedicated to EN polymer (Topas E−140). [ABSTRACT FROM AUTHOR]

• Pickering emulsions based on gliadin/arabinoxylan nanoparticles (GANPs) were fabricated. • GANPs with different gliadin/arabinoxylan (G/AX) ratios had distinct effects on emulsion properties. • Pickering emulsion with G/AX ratio of 1:4 showed strongest oxidative stability. • Percolating gel net-work mechanism conferred the emulsion superior stabilization. In the present work, the Pickering emulsions with enhanced oxidation stability were fabricated using gliadin (G)/arabinoxylan nanoparticles (GANPs). The influence of different G/AX ratios on the properties of GANPs and corresponding physicochemical characteristics of Pickering emulsions were investigated. Results indicated that the droplet size and ζ-potential of Pickering emulsions declined with the decrease of G/AX ratios. Pickering emulsion with the smallest G/AX ratio (1:4) exhibited excellent oxidative and coalescence stability due to the formation of viscoelastic gel network, which was supported by confocal laser scanning microscopy (CLSM) images. Furthermore, the increase of salt ions in a lower concentration (0–0.2 M) was conducive to the flocculation of the droplets, while further increasing the NaCl concentration impaired the emulsion stability. Such elements revealed that G/AX complex is a promising stabilizer of Pickering emulsions with prominent antioxidant activity, which have favorable potential applications in protecting the functional properties of polyunsaturated fatty acids (PUFAs). [ABSTRACT FROM AUTHOR]

Profiles of soil organic carbon (SOC) are often characterized by a steep increase of 14C age with depth, often leading to subsoil 14C ages of more than 1000 years. These observations have generally been reproduced in SOC models by introducing a SOC pool that decomposes on the time-scale of millennia. The overemphasis of chemical recalcitrance as the major factor for the persistence of SOC was able to provide a mechanistic justification for these very low decomposition rates. The emerging view on SOC persistence, however, stresses that apart from molecular structure a multitude of mechanisms can lead to the long-term persistence of organic carbon in soils. These mechanisms, however, have not been incorporated into most models. Consequently, we developed the SOC profile model COMISSION which simulates vertically resolved SOC concentrations based on representations of microbial interactions, sorption to minerals, and vertical transport. We calibrated COMISSION using published concentrations of SOC, microbial biomass and mineral-associated OC (MOC), and in addition, 14C contents of SOC and MOC of a Haplic Podzol profile in North-Eastern Bavaria, Germany. In order to elucidate the contribution of the implemented processes to the 14C age in different parts of the profile, we performed model-experiments in which we switched off the limitation of SOC decomposition by microbes, sorptive stabilization on soil minerals, and dissolved OC (DOC) transport. By splitting all model pools into directly litter-derived carbon and microbe-derived organic carbon, we investigated the contribution of repeated microbial recycling to 14C ages throughout the profile. The model-experiments for this site lead to the following implications: Without rejuvenation by DOC transport, SOC in the subsoil would be on average 1700 14C years older. Across the profile, SOC from microbial recycling is on average 1400 14C years older than litter-derived SOC. Without microbial limitation of depolymerization, SOC in the subsoil would be on average 610 14C years younger. Sorptive stabilization is responsible for relatively high 14C ages in the topsoil. The model-experiments further indicate that the high SOC concentrations in the Bh horizon are caused by the interplay between sorptive stabilization and microbial dynamics. Overall, the model-experiments demonstrate that the high 14C ages are not solely caused by slow turnover of a single pool, but that the increase of 14C ages along a soil profile up to ages >1000 years is the result of different mechanisms contributing to the overall persistence of SOC. The dominant reasons for the persistence of SOC are stabilization processes, followed by repeated microbial processing of SOC. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the effect of the film thickness and lattice spacing of Zr oxides on the crystalline structures of Zr oxide films formed by atomic layer deposition (ALD) and sputtering methods to achieve higher-k tetragonal ZrO2 (t-ZrO2) films. In the ALD case, the t-ZrO2 crystalline structure stably formed over a wide range of film thicknesses (8 to 130nm). The Zr oxide films with a t-ZrO2 structure prepared by ALD and post-deposition annealing at 350°C achieved a relative permittivity of 35±2. On the other hand, the ratio of the t-ZrO2 phase to the monoclinic (m-) ZrO2 phase decreases with increasing thickness of the Zr oxide film formed by sputtering, although it can be increased by Ge incorporation. Focusing on the relationship between the lattice spacing and the crystalline phase of Zr oxide, the t-ZrO2 crystalline structures are stably formed with decreasing lattice spacing of the t-ZrO2 crystalline structure. The effect of the lattice spacing on the t-ZrO2 crystalline structure formation is suitably explained in terms of the bulk (volume) energy of the t-ZrO2 phase. [Copyright &y& Elsevier]

Abstract: Stabilization offered by physicochemical protection in hierarchical soil aggregates is critical for building and maintaining soil C and N stocks. However, it is unclear if complex stabilization mechanisms can completely recover when native plant communities are re-established on soils depleted of C and N by agriculture. We isolated particulate organic matter (POM) and silt- and clay-sized fractions from four structurally defined locations within soil collected from an agricultural field, prairies restored for 3–33 years, and a never-cultivated remnant prairie. We used aggregate hierarchy to define our four soil locations: non-aggregated material, free microaggregates, macroaggregates (excluding encapsulated microaggregates), and microaggregates-within-macroaggregates. We found that the duration of linear soil C and N accumulation differed among aggregate-occluded pools in relation to the combined influences of soil mass redistribution and increases in C and N concentrations. Silt in microaggregates isolated from within macroaggregates contributed the greatest quantities of C and N to whole soil, yet reached steady state C and N contents that were only 59% (C) and 56% (N) of those observed in the remnant prairie soil. Although the C and N contents of most pools were still well below the amounts in the reference remnant prairie, the overall distribution of C among pools was similar to the remnant within 33 years of restoration, suggesting that SOM stabilization mechanisms do largely recover in the first decades after cessation of tillage and restoration of the plant community. Thus, the pools that fell short of pre-cultivation C and N contents within the timespan of the chronosequence might continue to build C and N even though they appeared to be at steady state at the time of sampling, possibly because not enough time has passed at the current input rate or because of lags in SOM transfer among pools. We hypothesize that several “transient steady states” could occur in some SOM pools along the way to an overall whole-soil steady state that could take centuries to achieve. [Copyright &y& Elsevier]

Abstract: The potential energy surface describing quantitatively the dynamics of the collision induced dissociation reactions CsBr+Xe→Cs+ +Br− +Xe, CsXe+ +Br− is used to explore detailed dynamics of the reverse process of direct three-body recombination of the Cs+ and Br− ions undergoing a central collision. For a stepwise analysis of the course of the elementary process, visualization of the trajectory and of the energy state of each pair of the particles is employed. Several different mechanisms of the reaction are found. Their occurrence depends on the impact parameter of the collision of the third body with the recombining pair and on the angles determining the spatial orientation of the ion velocities. The major role in stabilization of the recombination products is played by the repulsion potentials between the ions and the third body, but the amount of energy transferred depends not only on the repulsion interaction strength. Recombination is shown to be able to happen for very low energies of repulsion between the third body and the ions and even in the complete absence of repulsion. In all the cases, the particular recombination mechanism is determined by the dynamical features of the collision. The relation between the kinematic parameters of a collision of the three particles and the recombination mechanism is considered. [Copyright &y& Elsevier]

Abstract: Phenolic compounds are part of the secondary metabolism of plants and are of great importance for their survival in unfavourable environment. A class of phenolic compounds easily found in the Plant Kingdom, is anthocyanins, a flavonoid category. They are water-soluble pigments that confer the bright red, blue, and purple colors of fruits and vegetables and promote several health benefits due to their diverse biological activities. Different factors affect the color and stability of these compounds including pH, temperature, light, presence of copigments, self-association, metallic ions, enzymes, oxygen, ascorbic acid, sugar, among others. For this reason many studies have been conducted with the aim to increase the stability of these substances. Therefore, the present review highlights studies on the stabilization of anthocyanins and presents latent anthocyanin stabilization mechanisms and demonstrates the potentiality of the main techniques used: association and encapsulation. [Copyright &y& Elsevier]

Abstract: At first glance, metal foams appear to be peculiar. On the one hand, they show a high stability with life times of minutes up to hours. On the other hand, metal foams should be highly unstable due to capillary forces. Generally, the cell structures show odd cell configurations. In addition, the cell walls are thick, about 100 m, and exhibit pronounced local swellings and indents. In this paper, we show that this apparent discrepancy is a direct consequence of an underlying foam stabilization mechanism for metals which is based on a barrier effect induced by particles confined in cell walls. Numerical simulation based on a lattice Boltzmann model shows how particles get confined within cell walls and induce a repulsive disjoining pressure there. This disjoining pressure is responsible for the high foam stability generally observed. The identified stabilization mechanism also explains the presence of irregular cell structures generally observed for metal foams and represents the basis for further developments. [Copyright &y& Elsevier]

Abstract: In this paper we propose a new general framework for the construction and the analysis of discontinuous Galerkin (DG) methods which reveals a basic mechanism, responsible for certain distinctive stability properties of DG methods. We show that this mechanism is common to apparently unrelated stabilizations, including jump penalty, upwinding, and Hughes–Franca type residual-based stabilizations. [Copyright &y& Elsevier]

Micron-sized poly(vinyl acetate) particles were produced directly by radiation-induced dispersion polymerization in aqueous alcohol media using poly(N-vinylpyrrolidone) (PVP) as a steric stabilizer at room temperature. This method takes advantages of the specialities of radiation-induction, and highly uniform polymer microspheres were obtained. The effects of stabilizer content and medium polarity on the particle size and the size distribution were investigated. Based on the experimental results and radiation grafting theory, the stabilization mechanisms were discussed primarily. [Copyright &y& Elsevier]

Nanocelluloses in recent years have garnered a lot of attention for their use as stabilizers of liquid-liquid and gas-liquid interfaces. Both cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) have been used extensively in multiple studies to prepare emulsions and foams. However, there is limited literature available that systematically discusses the mechanisms that affect the ability of nanocelluloses (modified and unmodified) to stabilize different types of interfaces. This review briefly discusses key factors that affect the stability of Pickering emulsions and foams and provides a detailed and systematic analysis of the current state knowledge on factors affecting the stabilization of liquid-liquid and gas-liquid interfaces by nanocelluloses. The review also discusses the effect of nanocellulose surface modifications on mechanisms driving the Pickering stabilization of these interfaces. [Display omitted] • Factors affecting the stabilization of interfaces by nanocelluloses • Stabilization mechanisms of Pickering emulsions and foams containing nanocelluloses • Properties of liquid-liquid and gas-liquid interfaces with adsorbed nanocelluloses • Effect of surface modification on the behavior of nanocelluloses at interfaces [ABSTRACT FROM AUTHOR]

Acid-induced aggregation of casein micelles is a major problem that should be addressed in the production of acidified milk drinks (AMDs). Polysaccharide stabilizers, especially anionic polysaccharides, are usually added to maintain the physical stability of AMDs. The present review gives an update on the polysaccharide stabilizers explored to stabilize AMDs based on the research progress in the past decade, including the commonly used high methoxyl pectin (HMP), soluble soybean polysaccharide (SSPS), and carboxymethyl cellulose (CMC). Various factors that affect the stability of AMDs are introduced, such as milk solid content, polysaccharide concentration, environmental conditions, and processing conditions, with an emphasis on the molecular parameters of polysaccharides. The stabilization mechanisms are generally believed to originate from electrostatic repulsion and steric stabilization. In addition, the viscosifying effect of unadsorbed polysaccharides or the formation of a weak gel network may also be involved contributing to the stability of AMDs. The future trends of AMDs are finally outlined, regarding further clarification on the contribution of different stabilization effects, structure design and modification of polysaccharide stabilizers, and development of plant-protein based acidified beverages. [Display omitted] • Polysaccharide stabilizers for AMDs are summarized based on the latest advances. • Multiscale assessment methods for the stability of AMDs are introduced. • Influence factors are correlated emphatically to stabilizer molecular parameters. • Polysaccharide induced stabilization mechanisms of AMDs are reviewed. [ABSTRACT FROM AUTHOR]

Crop productivity and soil health are limited by organic carbon (OC), however, the variations in the mechanisms of SOC preservation in a complete soil profile subjected to long-term fertilization remains unclear. The objective of the study was to examined the content and profile distribution of the distinctive SOC protection mechanisms on a complete profile (0–100 cm) of Eumorthic Anthrosols in Northwest China after 23 years of chemical and manure fertilization. The soil was fractionated by combined physical-chemical and density floatation techniques. Throughout the profile, significant variations were observed among fractions. In the topsoil (0–20 and 20–40 cm), mineral coupling with the fertilization of manure (MNPK) enhanced total SOC content and recorded for 29% of SOC in the 0–20 and 20–40 cm layers. Moreover, MNPK increased the SOC content of the unprotected cPOC fraction by 60.9% and 61.5% in the 0–20 and 20–40 cm layer, while SOC content was low in the subsoil layers (40–60, 60–80 and 80–100 cm, respectively) compared with the control (C). The highest OC under MNPK in physically protected micro-aggregates (μagg) (6.36 and 6.06 g C kg−1), and occluded particulate organic carbon (iPOC) (1.41 and 1.29 g C kg−1) was found in the topsoil layers. The unprotected cPOC fraction was the greatest C accumulating fraction in the topsoil layers, followed by μagg and H-μSilt fractions in the soil profile, implying that these fractions were the most sensitive to the fertilization treatments. Overall, the unprotected, physically protected, and physico-chemically protected fractions were the dominant fractions for the sequestration of carbon across fertilization treatments and soil layers. Image 1 • Physical protection mechanisms were the most dominant in soil profile. • CPOC was the most sensitive fractions. • MNPK and SNPK caused accretion of total SOC content in a soil profile. • The correlations suggested that this soil has not yet reached C saturation. [ABSTRACT FROM AUTHOR]

Nanoscale zero-valent iron (nZVI) is regarded as one of the most effective materials for environmental remediation. However, nZVI particles tend to aggregate rapidly due to their magnetic properties which leads to decrease their effectiveness in water treatment. To overcome the aggregation problem of nZVI particles and increase their reactivity, four different polymers were used during the synthesis of nZVI including polyacrylamide (PAA), carboxymethyl cellulose (CMC), Polyethylene sorbitan monolaurate (PSM) and polyvinylpyrrolidone (PVP). These polymers were used with different mass ratios varied between 0.04 and 0.40 %, in order to acquire the optimal mass ratio with nZVI and achieve the highest removal of nitrate and phosphorus. The mechanism of polymers adsorption onto the surface of nZVI was explored by conducting SEM-EDX, XRD, and FTIR analysis. TEM was used to examine the suface morphology of nZVI before and after being stabilized with 4 polymers. Results showed that, the sizes were found to be 9.53, 65.4, 106.4, 106.6 and 108.8 nm, using TEM and ImageJ, corresponding to CMC-nZVI, bare-nZVI, PAA-nZVI, PSM-nZVI and PVP-nZVI, respectively. The efficiency of bare and stabilized nZVI on nitrate reduction was found to be in the following the order: PVP-nZVI 99.5% > PAA-nZV 99% > PSM-nZV 97% > CMC-nZVI 70% > bare-nZVI 55.6%. Whereas, for phosphorus adsorption, PAA-nZV 97% was the most effective type, followed by bare-nZVI 76.3%, PSM-nZVI 75%, PVP-nZVI 73% and CMC-nZVI 71%. Therefore, PAA-nZVI exhibited an excellent performance over the rest for both nitrate and phosphorus removal at a wide range of pH. For this reason, four kinetic models were investigated to describe the reaction rate of nitrate and phosphorus removal by PAA-nZVI. Describing the stabilization mechanism of nZVI using four different functional polymers in addition to the role of these polymers to improve the removal percentage of nitrate and phosphorus by nZVI. Unlabelled Image • The used polymers were bonded to nZVI through carbonyl and hydroxyl groups. • The polymers changed the outer form of nZVI which resulted in preventing the particle aggregation. • Polyacrylamide was an efficient polymer enhanced nitrate and phosphorus removal. • Carboxymethyl cellulose was the best polymer for producing low-size particles < 10 nm. • Polyvinylpyrrolidone/nZVI is highly recommended for the reducible contaminants. [ABSTRACT FROM AUTHOR]

Long term fertilization may have a significant effect on soil organic carbon (SOC) fractions and profile distribution. However, previous research mostly explored the SOC in the topsoil and provided little or no information about its distribution in deeper layers and various protection mechanisms particularly under long-term fertilization. The present study investigated the contents and profile distribution (0–100 cm) of distinct SOC protection mechanisms in the Mollisol (black soil) of Northeast China after 35 years of mineral and manure application. The initial Organic Matter content of the topsoil (0–20 cm) ranged from 26.4 to 27.0 g kg−1 soil, and ploughing depth was up to 20 cm. A combination of physical-chemical fractionation methods was employed to study various SOC fractions. There were significant variations throughout the profile among the various fractions and protection mechanisms. In topsoil (to 40 cm), mineral plus manure fertilization (MNPK) increased the total SOC content and accounted for 16.15% in the 0–20 cm and 12.34% in the 20–40 cm layer, while the manure alone (M) increased the total SOC by 56.14%, 48.73% and 27.73% in the subsoil (40–60, 60–80 and 80–100 cm, respectively). Moreover, MNPK and M in the topsoil and subsoil, respectively increased the unprotected coarse particulate organic carbon (cPOC) (48% and 26%, respectively), physically protected micro-aggregate (μagg) (20% and 18%, respectively) and occluded particulate organic carbon (iPOC) contents (279% and 93%, respectively) compared with the control (CK). A positive linear correlation was observed between total SOC and the cPOC, iPOC, physico-biochemically protected NH-μSilt and physico-chemically protected H-μSilt (p < 0.01) across the whole profile. Overall, physical, physico-biochemical and physico-chemical protection were the predominant mechanisms to sequester carbon in the whole profile, whereas the biochemical protection mechanisms were only relevant in the topsoil, thus demonstrating the differential mechanistic sensitivity of fractions for organic carbon cycling across the profile. Unlabelled Image • Sole application of manure enhanced SOC content in the subsoil. • cPOC and iPOC were the most robust indicators of SOC sequestration throughout the profile. • Physical protection was important for C sequestration in top- as well as in the subsoil. • Aggregate-related chemical and biochemical protection was dominant across the profile. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is the largest pool of non-sedimentary terrestrial carbon (C) and small changes in vertical SOC fluxes in the erosion-transport-deposition system could have a significant effect on atmospheric C levels. The ongoing sink/source discussion related to SOC seems to depend on which mechanisms are dominant during each of the three stages of soil erosion: detachment, transportation and deposition. Understanding C dynamics during each phase of soil erosion is essential to accurately assess the net effect of erosion. Currently, there is a knowledge gap when it comes to the movement of mobilized SOC from the site of detachment to the depositional site. This review provides an overview on the current understanding of the fate of eroded SOC during the transport phase of soil erosion. The stability of SOC appears to be a logistic interplay between SOC accessibility, presence of decomposers and suitable abiotic conditions. The main protection mechanisms of SOC are physical and/or chemical protection, which both make SOC inaccessible to decomposers and hence prevent mineralization. Transport subjects the SOC to disturbances and changing environmental conditions which interfere with the effectiveness of the protection mechanisms. The vulnerability of these mechanisms to erosive transport are not yet known. Increased physical impact is associated with disaggregation which releases previously protected SOC. Changes in geochemical composition of soil potentially changes the extent of organo-mineral bindings and hence either strengthen or weaken chemical protection. Complex chemical structures might result in more resistant C called biochemical stable SOC and is vulnerable to destabilization during transport due to changes in (a)biotic conditions along the trajectory. A complete understanding of the fate of mobilized SOC during transportation is essential to assess the net effect of soil erosion under different conditions. Standardization of both methodology and terminology in the field of soil erosion will further contribute to resolving the controversy on the net effect of erosion. The focus for future research should be on documenting the different interacting processes active during erosive transport and their effect on SOC fluxes. [ABSTRACT FROM AUTHOR]