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Both fungi and bacteria produce complicated volatile organic compound (VOC) mixtures that include alcohols, aldehydes, ketones, aromatics, amines, terpenes, chlorinated hydrocarbons, and sulfur-containing compounds. This chapter discusses the VOCs that arise from fungi and bacteria. Many of the biogenic VOCs are polar compounds that have distinct odors and low odor thresholds, and have been reported to produce discomfort in building occupants. Sorbent sampling involves the collection of VOCs on adsorbents that attract and retain the compounds for later analysis. Whole air sampling with cryogenic preconcentration can capture a wide range of VOCs. Biogenic compounds can be identified from cultures as well as from contaminated materials brought into the laboratory using either dynamic or static headspace sampling approaches. Samples may also be generated directly from fungi, bacteria, and/or the substrate to determine VOCs as well as semi- and non-volatile components that may be present in both liquid and solid phases.

This article aims to analyze the dynamics of freezing and thawing of Antarctic lakes located in ice-free areas on Nelson Island and Fildes Peninsula, where response to changes in air temperature and precipitation rates occur rapidly, during the period from July 2016 to December 2018. In these places, which are difficult to access, remote sensing is an important alternative, especially considering the use of active remote sensors such as the Synthetic Aperture Radar (SAR), which has less restriction regarding the presence of clouds over the study area. Three backscatter thresholds were defined (σ) for the identification of the physical state of the water of the lakes of the study region, applied in Sentinel 1A SAR (S1A) images under Horizontal Horizontal (HH) polarization and Interferometric Wide (IW) imaging mode. These images, along with the air temperature data obtained by the Interim Re-Analysis (ERA-Interim) atmospheric reanalysis model, provided the evidence for the interpretation of the freezing and thawing periods of the lakes. The thresholds applied for the definition of the physical state of the lake water were greater than - 14 dB for frozen water, between - 14 and - 17 dB for the surface, with up to 60% of their frozen area, and less than - 17 dB for open water. The temporal analysis revealed that the lakes start to thaw in October, become completely thawed in February, and freeze again in March. Nevertheless, it can be said that the S1A satellite allows a satisfactory identification of the liquid and solid phases of the water in the lakes of the study region.

Solid phase peptide synthesis (SPPS) has enabled widespread use of synthetic peptides in applications ranging from pharmaceuticals to materials science. The demand for synthetic peptides has driven recent efforts to produce automated SPPS synthesizers which utilize fluid-handling components common to chemistry laboratories to drive costs down to several thousand dollars. Herein, we describe the design and validation of a more ‘frugal’ SPPS synthesizer that uses inexpensive, consumer-grade fluid-handling components to achieve a prototype price point between US$300 and $600. We demonstrated functionality by preparing and characterizing peptides with a variety of distinct properties including binding functionality, nanoscale self-assembly, and oxidation-induced fluorescence. This system yielded micromoles of peptide at a cost of approximately $1/residue, a cost which may be further reduced by optimization and bulk purchasing.

The shrinking unreacted core model has been one of the most widely used models for the uncatalyzed reaction kinetics between the liquid/gas and the solid phases. However, the classical shrinking unreacted core model (CSUC model) is only applicable to spherical particles. Currently, the CSUC model has been used in many studies regardless of its applicable conditions. For example, Wang et al. (2016) investigated the decomposition kinetics of a rod-like residue and deduced the rate-controlling step using the CSUC model. The purpose of this comment is to propose a modified shrinking unreacted core model (shrinking cylinder model) suitable for materials with a high aspect ratio. The authors hope that this work will be helpful for kinetic analysis of rod-shaped and fiber-shaped materials in the uncatalyzed liquid/gas-solid reactions.

The natural excitonic circuitry of photosynthetic organisms, including light harvesting antennas, provides a distinctive example of a highly attractive bio-inspired alternative to electronic circuits. Excitonics, which capitalizes on spatially arranged optically active molecules ability to capture and transfer light energy below the diffraction limit of light has garnered recognition as a potential disruptive replacement for electronic circuits. However, assembly of optically active molecules to construct even simple excitonic devices has been impeded by the limited maturity of suitable molecular scale assembly technologies. An example of nanophotonic circuitry, natural light harvesting antennas employ proteins as scaffolds to organize and self-assemble light-active molecules into excitonic networks capable of capturing and converting light to excitonic energy, and transferring that energy at ambient temperature. Protein self-assembly is extremely complex due to the over 20 amino acids building blocks used in the self-assembly process and the difficulty of predicting how proteins actually fold. An alternative method for organization and self-assembly may be found in the field DNA nanotechnology. DNA nanotechnology provides the most viable means to organize optically active molecules as there are only four nucleic acid building blocks and well-established simple design rules. Leveraging DNA nanotechnology will meet the requirements of precise proximity (selectivity) and appropriate number (specificity) needed to create larger arrays of multifunctional optically active molecules. Employing the design rules of DNA self-assembly, we have designed, engineered and operated an all-optical excitonic switch consisting of donor and acceptor chromophores and diarylethene photochromic modulating units assembled with nanometer scale precision. This work demonstrates the first integration of three diarylethene photochromic units into a single DNA oligonucleotide. Photoisomerization of diarylethenes has been shown to be one of the fastest photochemical reactions thereby affording potential switching speeds in the 10's of picoseconds. Adopting diarylethenes as optically reversible switching units provided the ability to operate the all-optical excitonic switch through nearly 200 cycles without overt cyclic fatigue and excellent ON/OFF stability in both the liquid and solid phases. Assessing the static and dynamic cycling behavior of the all-optical excitonic switch allowed for the development of a model to predict characteristic switching times (τ) of 17.0 and 23.3 seconds for the liquid and solid phases, respectively which align well with the experimental data thereby validating the model. While these times are much faster than that of other non-optically based DNA-templated excitonic switches (τ ~ 10's of minutes), the times noted here are limited by the steady-state optical instrumentation, (i.e., photon flux, detector integration time, and slit cycling speed), used to characterize the all-optical excitonic switches. Our model predicts switching times in the picosecond range could be achieved with the use of a high peak power ultrafast laser. First-order calculations estimate the all-optical excitonic switch has a footprint 37X smaller, a smaller volume by over 3 orders of magnitude and over an order of magnitude less energy per cycle than a state-of-the-art MOSFET. These findings, combined with no production of waste products and the potential ability to switch at speeds in the 10's of picoseconds, establishes a prospective pathway toward all-optical excitonic circuits.

A coupled numerical approach is used to evaluate the influence of pore connectivity and microcracks on leaching kinetics in fully saturated cement paste. The unique advantage of the numerical model is the ability to construct and evaluate a material with controlled properties, which is very difficult under experimental conditions. Our analysis is based on two virtual microstructures, which are different in terms of pore connectivity but the same in terms of porosity and the amount of solid phases. Numerical fracturing was performed on these microstructures. The non-fractured and fractured microstructures were both subjected to chemical leaching. Results show that despite very different material physical properties, for example, pore connectivity and effective diffusivity, the leaching kinetics remain the same as long as the amount of soluble phases, i.e., buffering capacity, is the same. The leaching kinetics also remains the same in the presence of microcracks.

Background Oncolytic viruses are playing an increasingly important role in cancer immunotherapy applications. Given the preclinical and clinical efficacy of these virus-based therapeutics, there is a need for fast, simple, and inexpensive downstream processing methodologies to purify biologically active viral agents that meet the increasingly higher safety standards stipulated by regulatory authorities like the Food and Drug Administration and the European Agency for the Evaluation of Medicinal Products. However, the production of virus materials for clinical dosing of oncolytic virotherapies is currently limited—in quantity, quality, and timeliness—by current purification technologies. Adsorption of virus particles to solid phases provides a convenient and practical choice for large-scale fractionation and recovery of viruses from cell and media contaminants. Indeed, chromatography has been deemed the most promising technology for large-scale purification of viruses for biomedical applications. The implementation of new chromatography media has improved process performance, but low yields and long processing times required to reach the desired purity are still limiting. Results Here we report the development of an interference chromatography-based process for purifying high titer, clinical grade oncolytic Newcastle disease virus using NatriFlo® HD-Q membrane technology. This novel approach to optimizing chromatographic performance utilizes differences in molecular bonding interactions to achieve high purity in a single ion exchange step. Conclusions When used in conjunction with membrane chromatography, this high yield method based on interference chromatography has the potential to deliver efficient, scalable processes to enable viable production of oncolytic virotherapies.

This chapter provides an overview of the hydrolytic reactions of Al in aqueous solutions and presents the salient features of polynuclear Al structures. It evaluates current methods of detecting and quantifying polynuclear forms of Al and discusses the mechanisms of their formation and certain implications of the polynuclear Al species to soil-water systems. Recent studies have utilized spectrophotometers that permit continuous monitoring of absorbance increases that occur after rapid mixing of the ferron reagent and a partially neutralized Al solution. Th chapter also highlights the origins and genesis of polynuclear Al species. A potentially important mechanism for the formation of polynuclear Al species involves polynucleation at the mineral water interface. Nucleation of Al mononuclear and polynuclear species into colloidal or distinct solid phases is an important phenomenon utilized in physicochemical treatment of water and wastewaters.

We report the grand-canonical solution of a ternary mixture of discrete hard spheres defined on a Husimi lattice built with cubes, which provides a mean-field approximation for this system on the cubic lattice. The mixture is composed of pointlike particles (0NN) and particles which exclude up to their first (1NN) and second neighbors (2NN), with activities ${z}_{0}, {z}_{1}$, and ${z}_{2}$, respectively. Our solution reveals a very rich thermodynamic behavior, with two solid phases associated with the ordering of 1NN ($S1$) or 2NN particles ($S2$), and two fluid phases, one being regular ($RF$) and the other characterized by a dominance of 0NN particles ($F0$ phase). However, in most part of the phase diagram these fluid ($F$) phases are indistinguishable. Discontinuous transitions are observed between all the four phases, yielding several coexistence surfaces in the system, among which a fluid-fluid and a solid-solid demixing surface. The former one is limited by a line of critical points and a line of triple points (where the phases $RF\ensuremath{-}F0\ensuremath{-}S2$ coexist), both meeting at a special point, after which the fluid-fluid coexistence becomes metastable. Another line of triple points is found, connecting the $F\ensuremath{-}S1, F\ensuremath{-}S2$, and $S1\ensuremath{-}S2$ coexistence surfaces. A critical $F\ensuremath{-}S1$ surface is also observed meeting the $F\ensuremath{-}S1$ coexistence one at a line of tricritical points. Furthermore, a thermodynamic anomaly characterized by minima in isobaric curves of the total density of particles is found, yielding three surfaces of minimal density in the activity space, depending on which activity is kept fixed during its calculation.

This work builds the phase diagrams of hard spherocylinders for aspect ratios of 8, 10 and 16 in the quasi-two-dimensional regime. The fact that these phase diagrams share similar characteristics allows for the construction of a master phase diagram. Besides delimiting the isotropic, nematic, and solid phases, particular attention is paid to the wetting behavior of the particles on the confining walls.

A novel mathematical model is developed to calculate the temperature distribution on the surface and bulk of a steel plate under the laser hardening process. The model starts with the basic heat equation then it is developed into a volumetric form and is connected to the various solid existing phases. The proposed model is based on three influencing parameters of the laser hardening process which are the velocity of the laser spot and irradiation time. The results are compared with the available experimental data reported in the literature. The volumetric model provides an assessment of temperature distribution in both the vertical and horizontal axis. Laser irradiation at sufficiently high fluence can be used to create a solid-state phase change on the surface. Primary calculations show that the temperature profile has a Gaussian distribution in horizontal x and y-axis and presents an exponentially decreasing in the horizontal and vertical depth directions.

Paramagnetic spin systems with spontaneously broken spatial symmetries, such as valence bond solid (VBS) phases, can host topological defects carrying non-trivial quantum numbers, which enables the paradigm of deconfined quantum criticality. In this work, we study the properties of topological defects in valence plaquette solid (VPS) phases on square and cubic lattices. We show that the defects of the VPS order parameter, in addition to possessing non-trivial quantum numbers, have fracton mobility constraints deep in the VPS phase, which has been overlooked previously. The spinon inside a single vortex cannot move freely in any direction, while a dipolar pair of vortices with spinon pairs can only move perpendicular to its dipole moment. These mobility constraints, while they persist, can potentially inhibit the condensation of vortices and preclude a continuous transition from the VPS to the N\'eel antiferromagnet. Instead, the VPS melting transition can be driven by proliferation of spinon dipoles. For example, we argue that a $2d$ VPS can melt into a stable gapless phase in the form of an algebraic bond liquid with algebraic correlations and long range entanglement. Such a bond liquid phase yields a concrete example of the elusive $2d$ Bose metal with symmetry fractionalization. We also study $3d$ valence plaquette and valence cube ordered phase, and demonstrate that the topological defects therein also have fractonic dynamics. Possible nearby phases after melting the valence plaquettes or cubes are also discussed.

This chapter is devoted to solidification of binary A-B alloys of nominal solute composition Co. The interpretation of a binary phase diagram depends on the composition of an alloy (Co Ce) and its freezing temperature range \(T_{s}\leq T_{f}^{\ast }\leq T_{l}\), the solidification velocity. Assuming that the alloy is at equilibrium at a low solidification velocity, one has to determine the type and morphology of the solid phases resulting from solidification, compositions of the liquid and solid phases at a particular freezing temperature, the mass fractions of the phases, and the degree of any undercooling ΔT.

This work presents the fundamentals and exemplary applications of a generalized model for precipitation, aggregation and ripening processes including the formation of solid phases with two dimensions. The particle formation is governed by a widely applicable population balance approach. Solid formation processes are described via the numerically efficient Direct Quadrature Method of Moments (DQMOM), which can calculate the evolution of multiple solid phases simultaneously. The particle size distribution (PSD) is approximated by a summation of delta functions while the moment source term is approximated by a two-point quadrature. The moments to calculate the multivariate distributions are chosen carefully to represent the second order moments. Solid formation is based on the model of Haderlein et al. (2017) and is extended by a multidimensional aggregation model. Now, the influences of mixing, complex hydrochemistry and particle formation dynamics including nucleation, growth and aggregation on multiphase precipitation processes are modelled and simulated along independent dimensions with high efficiency.

В работе рассмотрены вопросы адсорбционной активности лигносульфонатов, получаемых различными способами делигнификации и продуктов их модификации различными агентами. Исследование проводилось методом измерения поверхностного натяжения растворов лигносульфонатов различной концентрации на границе жидкость–жидкость с последующим определением величины предельной адсорбции на твердых фазах. Также были посчитаны такие адсорбционные характеристики, как толщина монослоя, посадочная площадь молекулы, молекулярные массы лигносульфонатов и их модифицированных форм. В качестве твердых фаз использовали глину и кварцевый песок. Установлено, что эффективность работы лигносульфонатных систем значительно увеличивается при модификации их различными агентами, в частности солями поливалентных катионов, фосфоновыми функциональными группами, что подтверждено расчетами работы адсорбции., The paper discusses the adsorption activity of lignosulfonates obtained by various delignification methods and products of their modification by various agents. The study was carried out by measuring the surface tension of lignosulphonate solutions of various concentrations at the liquid-liquid boundary, followed by determining the value of marginal adsorption at solid phases, and adsorption characteristics such as the thickness of the monolayer, the landing area of the molecule, the molecular weights of lignosulphlenates and their modified forms were also calculated. Clay and quartz sand were used as solid phases. It has been found that the efficiency of lignosulfonate systems is significantly increased by modifying them with various agents, in particular polyvalent cation salts, phosphone functional groups, as confirmed by calculations of adsorption work.

Micro-pollutants (MPs) are of great concern to public health and the environment because they present as microconcentrations and can accumulate in humans via the food chain and drinking water. Long-term exposure to MPs can result in high-risk health problems such as endocrine disruption and cancer. To cope with this issue, treatment technologies have been developed and applied to wastewater treatment plants to remove MPs. These technologies are diverse, for example, physical, chemical, and biological, such as membrane, advanced oxidation, anaerobic, activated sludge, and adsorption processes. They demonstrate certain efficiencies in removing MPs in both aqueous and solid phases. Another rising concern of MPs relates to metabolites because they can be more toxic than the parent compounds. Understanding the transformation mechanism of MPs and their metabolites is still challenging. Therefore, in addition to treatment technologies, management policies are also a sustainable strategy for alleviating the impact of MPs. Establishing discharge standards and life cycle and health risk assessment for MPs requires integrated MP treatment and management; however, these are time-consuming and methodical procedures.

A procedure combining supercritical CO2 and ultrasound-assisted (USC-CO2) extraction was developed to obtain rosmarinic acid (RA)-rich extracts from Perilla frutescens. Based on extraction yields and efficiencies, USC-CO2 was considered the best extraction method among the methods studied for obtaining RA from P. frutescens. The constant extraction rate period and the falling extraction rate period for USC-CO2 extraction of P. frutescens were 45 and 96 min long, respectively, and they were significantly shorter than those of traditional SC-CO2 (TSC-CO2) extraction. Furthermore, mass transfer coefficients were derived using the Sovova model for the fluid and solid phases from USC-CO2 extraction, with values of 9.752 × 10−3 and 4.203 × 10−3 min−1, respectively, which were obviously higher than those for TSC-CO2 extraction. Consequently, the theoretical solubilities of RA in the supercritical solvents used in dynamic USC-CO2 and TSC-CO2 extractions were estimated and found to be well correlated using three density-based models.

High Entropy Alloys (HEAs) are an increasingly dominant alloy design paradigm. The premise of entropic stabilization of single-phase alloys has motivated much of the research on HEAs. Chemical complexity may indeed help stabilize single alloy phases relative to other lower-entropy competing solid phases. Paradoxically, this complexity may de-stabilize these alloys against the liquid phase, potentially limiting the application space of HEAs at elevated temperatures. In this work, we carry out a comprehensive investigation of the phase stability in the fcc CoCrFeMnNiV-Al HEA space using a state of the art CALPHAD database. By using modern visualization techniques and statistical analysis we examine the trade-off between chemical complexity and stability against the liquid state and identify a potentially difficult to overcome barrier for development of high temperature alloys, at least within the conventional fcc HEA space. Limited experimental data seem to be consistent with this analysis.

Steeply inclined settler technology has been long used to separate liquid and solid phases in dilute streams in various industries. In the present paper, a new model to account for the capacity of this kind of settler, in the particular case of those consisting of a set of inclined conduits, is proposed. The model combines a mass balance similar to that leading to the Ponder, Nakamura and Kuroda theory of inclined settlers and a particle trajectory approach to derive a simple relation between settling element length, particle settling-mean flow velocity ratio and geometric characteristics. Two new dimensionless parameters are derived to account for shape effects in the mass balance and when comparing settler capacity at equal conduit cross sectional area. Good agreement with previous experimental results and less conservative results than previous models have been found.

The emerging occurrence of thallium (Tl) in environments arouses the imposition of effective technology for its remediation. Due to the low solubility of Tl(III), the oxidation-precipitation of Tl(I) is considered as an promising removal method. Here, we recycled Al beverage can powder (AlCP) as the substitute for zero-valent Al to conduct the Fenton-like reaction for Tl(I) oxidation and subsequently induced the Tl(III) precipitation via the alkalinization at pH 9.5. The Tl(I) removal mechanisms in AlCP systems with amendments of Fe(III) or Fe(II) were determined in relation to its speciation for both dissolved and solid phases. Results showed that although additions of Fe(III)/Fe(II) prompted the Tl(I) oxidation as compared with the pure AlCP system, they were detrimental to the Tl removal upon the alkalinization. While the greatest removal efficiency was ~ 92% in AlCP/Fe(III)/Fe(II) systems, up to 99.8% of total Tl could be removed from the pure AlCP system. The Tl-XANES data indicated that although Tl(III) dominated the Tl inventory (92 – 95%) on all solids collected upon the alkalinization, it preferred to precipitate as stable Tl2O3 in pure AlCP system but as labile Tl(III) in AlCP/Fe(III)/Fe(II) systems, which might sorb on precipitated Al (hydr)oxides. Such sorbed Tl(III) is subject to reduction and the further dissolution, accounting for the lower removal efficiency for Tl in the presence of Fe(III)/Fe(II). This study corroborated the comparable Tl(I) removal efficiency of AlCP to that of state-of-the-art (nano)composites, providing a niche opportunity to give consideration to both interests in hazard remediation and the waste reduction/reuse.

Diffusive gradient in thin films (DGT) for organics has received considerable attention for studying the chemical dynamics of various organic pollutants in the environment. This review investigates current limitations of DGT for organics and identifies several research gaps for future studies. The application of a protective outer filter membrane has been recommended for most DGT applications, however, important questions regarding longer lag times due to significant interaction or adsorption of specific groups of compounds on the outer membrane remain. A modified DGT configuration has been developed that uses the diffusive gel as the outer membrane without the use of an extra filter membrane, however use of this configuration, while largely successful, remains limited. Biofouling has been a concern when using DGT for metals; however, effect on the performance of DGT for organics needs to be systemically studied. Storage stability of compounds on intact DGT samplers has been assessed in select studies and that data is synthesized here. DGT has been used to describe the kinetic desorption of antibiotics from soils and biosolids based on the soil/biosolid physical-chemical characteristics, yet applications remain limited and requires further research before wide-scale adoption is recommended. Finally, DGT for organics has been rarely, albeit successfully, combined with bioassays as well as in vivo bioaccumulation studies in zebrafish. Studies using DGT combined with bioassays to predict the adverse effects of environmental mixtures on aquatic or terrestrial biota are discussed here and should be considered for future research.

In certain alloy systems, a liquid of a fixed composition freezes to form a mixture of two solid phases, one of which may be faceted and the other nonfaceted (i.e., a ‘degenerate’ or irregular eutectic). The role of trace metallic additions on the microstructure of the eutectic has received significant research interest over the last half-century, culminating in advances in theoretical, computational, and experimental fronts. The drastic morphological, topological, and crystallographic changes that accompany metallic additions strongly influence the mechanical properties of the as-synthesized eutectic microstructure. In this review, we survey the mechanistic origins leading to a modified eutectic microstructure and describe the current status in the field of eutectic solidification in the presence of metallic modifying agents. We will also discuss the remaining challenges and future opportunities that would help move the field forward and enable bottom–up tuning of the complex degenerate microstructures to technological demands.

Data on thermodynamic properties of liquid sodium–tin alloys are summarized, analyzed, and compared, and thermodynamic properties of solid phases are estimated. The possibilities of using tin and its alloys and compounds as anode materials for sodium-ion batteries are briefly considered.

The redox behaviour of uranium was investigated in 0.1 and 5.0 M NaCl solutions at 2 ≤ pHm ≤ 14.5 (pHm = –log [H+]) in the presence of different reducing chemical systems (Sn(II), Na2S2O4, Sn(II) + TiO2, Sn(II) + Fe(0), Sn(II) + Fe3O4). All experiments were performed under Ar atmosphere at T = (22 ± 2) °C. Uranium was added to independent batch samples as U(VI) (with [U]0 = 3.0⋅10−5 or 4.2⋅10−4 M), and the evolution of uranium concentration monitored for t ≤ 635 days. After attaining equilibrium conditions, [U] was found in all cases clearly below the solubility of U(VI) solid phases (UO3⋅2H2O(cr) or Na2U2O7⋅H2O(cr)) and in good agreement with the solubility of tetravalent UO2(am, hyd) as calculated with available thermodynamic data. This observation is in line with (pe + pHm) measurements, which in all cases fell in the stability field of U(IV). Solvent extraction and XANES confirmed also that uranium is predominantly found as U(IV) in the aqueous and solid phases investigated. No evidence on the formation of anionic hydrolysis species of U(IV) was obtained up to pHm = 14.5. Based on our long-term redox study, we conclude that previous investigations reporting the formation of U(OH)5– and U(OH)62− are possibly flawed by insufficient equilibration time, which prevented the complete reduction of U(VI) to U(IV). Our results further confirm that experimental pHm and Eh values measured in buffered systems can be considered as reliable parameters to predict the redox behaviour of U in dilute to concentrated NaCl systems.

Background: The research field of protein-protein interactions is interdisciplinary and specialized field that spans all aspects of biology, physics and chemistry. Therefore, in order to dis-cuss the protein-protein interaction in detail and rigorously, it is desirable to integrate knowledge and methods of many related fields including boundary areas such as biochemistry, biophysics and physi-cal chemistry in addition to biology, physics and chemistry. Objective: The purpose of this review is to overview current methods to confirm protein-protein inter-actions. Furthermore, I discuss future prospects of methodology based on current status. Results: It is often necessary to integrate, combine and validate multiple results from various methods to understand protein-protein interactions in detail. Conclusion: It might be desirable for the addition of tags, labeling, and immobilization to solid phas-es to be unnecessary, and to obtain information on affinity, kinetics, and structure via the analytical method for protein-protein interactions. Therefore, I argue that novel methods based on principles that have already been sufficiently studied in physics or chemistry, but insufficiently applied to the life sciences, should be established to further develop the study of protein-protein interactions.

Long-term storage of Fe(III)-As(V) co-precipitate wastes derived from the industrial As removal process poses the risk of secondary arsenic pollution to the local environment. However, its stability in only iron-reducing environment remains unclear. The effect of iron reduction by hydroquinone (QH2) on the stability of co-precipitate at Fe/As molar ratio of 5 was investigated in this study. The results showed that 16.5–93% of Fe(III) reduction in NaOH-neutralized co-precipitate caused 0.1–11% (0.1–8.5 mg L-1) As release and 0.9–46% (2.6–130 mg L-1) Fe(II) release at pH 4 and 6. Most of the As(V) and more than half of the Fe(II) generated by the reductive decomposition of Fe(III)-As(V) co-precipitate were retained in solid phases. Solid characterization and thermodynamic calculation indicated that amorphous Fe3(AsO4)2 was probably the major secondary mineral for As immobilization. At pH 8, 11–39% As and less than 4% Fe(II) were released into solution after 3.6–87% Fe(III) was reduced to Fe(II). Both amorphous Fe3(AsO4)2 and Fe(II,III) (hydr)oxides were responsible for As retention. The solubility of NaOH-neutralized co-precipitates in terms of dissolved As concentration upon Fe(III) reduction at pH 4, 6 and 8 with QH2/Fe(III) mol of 1 was lower than that in oxic environment. It was also lower than the solubility of Ca(OH)2-neutralized co-precipitate after Fe(III) reduction at pH 4 and 6.

Bioleaching of heavy metals from sewage sludge is an effective method for decontamination of sewage sludge. The process is currently under active investigation for its improvement of sewage sludge dewatering. The bioleaching with recirculation of the liquid and solid phases of sewage sludge is of considerable interest for the development of the bioleaching method itself, and for deeper investigation of its influence on the sludge dewatering. This work presents and verifies a mass balance model of elements for bioleaching of heavy metals from sewage sludge by indigenous iron-oxidizing bacteria with recirculation of the liquid phase of the treated sludge. Good correspondence between the model predictions and the performed experiments gives ground for further development of the model to describe substances that are not conserved during the bioleaching, especially extracellular polymeric substances that impede sewage sludge dewatering. The mass balance model is presented in a form that also describes recirculation of the solid phase of sewage sludge during the bioleaching. Recirculation of the liquid and solid phases of sewage sludge during the bioleaching, together with the mass balance model, give useful tools for future investigation and development of dewatering of sewage sludge with the use of the bioleaching process.

Atom-precise, ligand-stabilized metalloid clusters have emerged as outstanding model systems to study fundamental structure and bonding situations of compositionally related molecules and extended solid phases. However, this fascinating field of research is still largely restricted to homometallic and pseudo-heterometallic systems of closely related d-block metals. In this review, we will highlight our own and others' efforts to project the structural and compositional diversity of intermetallics with dissimilar d- and p-block metal combinations, particularly the Zintl and Hume-Rothery phases, onto the molecular level in order to bridge the still gaping chasm between heterometallic molecular coordination chemistry and solid-state intermetallics. Herein, fundamental synthetic approaches, as well as structural and electronic properties of thus accessible "molecular alloys" will be addressed, and placed against their exceptional position as intermediates on the way to nanomaterials.

The phase relationships in silica rich area in the SiO2–SrO–Al2O3 system were determined experimentally at 1723 K (1450 °C), 1823 K (1550 °C) and 1873 K (1600 °C) using quenching technique. Phases of the quenched samples were examined and identified using light optical microscopy (LOM), scanning electron microscope (SEM) and energy dispersive x-ray spectroscopy (EDS). X-ray Diffraction (XRD) was used to confirm the presence of solid phases. Based on the experimental results, the liquidus projections in the silica rich area for the studied temperatures were constructed.

The phase state of the fluid in the H2O–KF ± KCl ± NaF system is studied in the presence of quartz for an experimental assay of the mutual influence of various salts of the fluid-forming mixture on heterogeneous fluid equilibria. The fluid inclusions were synthesized in quartz by the fracture healing method from solutions with KF + KCl and KF + NaF mixtures at 1 or 2 kbar and 700, 750, or 800°C. The results of the fluid inclusion study indicate a heterogeneous state of the fluid and variation in the fluid composition during experiments as a result of its interaction with quartz. The increase in temperature and pressure, as well as variation in the proportions of the salt contents in the fluid-forming mixture, changed the course of chemical reactions. After all the experiments, a glassy phase was observed in some types of inclusions. It is known that aqueous KF or KCl solutions, the solubility of which increases during heating, are characterized by phase equilibria of systems of the first type (Valyashko, 1990), when liquid and vapor are equilibrated for a heterogeneous state of the fluid. In this case, some inclusions should homogenize to vapor. However, no similar inclusions were observed in contrast to denser fluid phases (liquids), which are typical of the upper heterogeneous area of systems of the second (P–Q) type. Some inclusions host solid phases, the solubility of which decreases as the temperature increases. The results of experiments in the presence of KF + NaF solutions showed that the amount of inclusions of heterogeneous entrapment increases at higher temperatures simultaneously with a decrease in the H2O content of the glassy phase.

The purpose of this work was to theoretically and experimentally study the reactions that occur during low-pressure nitriding. A series of specimens made of 42CrMo4 and 41CrAlMo7 and C22 steels were low-pressure nitrided. The structure of the materials, the hardness and the thickness of the nitride layers, as well as any reactions that occurred in the gas and solid phases were tested. The process kinetics were discussed. The findings showed that a build-up of the nitrided layer from a low-pressure process depends on the kinetics of surface processes. However, a characterization of the process with nitriding potential is not justified and should be replaced with a rate of ammonia dissociation in low-pressure processes.

The solubility of nesquehonite (MgCO3·3H2O) and calcite (CaCO3) in carbonated water with CO2 pressure of between 1 and 5 MPa was measured from 293.15 to 343.15 K by the inductively coupled plasma optical emission spectrometry (ICP-OES) analysis method. The results showed that the solubility increased with CO2 pressure but decreased with temperature in all of the studied situations, and for the ones where the two solid phases coexisted, nesquehonite’s solubility changed little from that of the single-existing cases while calcite’s declined by 1 order of magnitude. The solubility was correlated with both temperature and CO2 pressure by empirical equations in a concise form.

This paper summarizes data on new approaches to the detection, identification, and quantitative determination of manifestations of spatial inhomogeneities in the chemical composition and structure of mixtures of inorganic solid phases by a standardless differential dissolution (DD) stoichiographic method. We present mathematical modeling results for DD processes in different models for mixtures of solid phases. Based on the modeling results, we formulate rules of stoichiographic calculations for DD results, which are confirmed in identifying manifestations of spatial inhomogeneities in the phase composition of real systems, including fanlike separation of phase mixtures, without their selective separation.

The present study deals with the preparation of oxidized biochar fibres derived from Luffa cylindrica sponges and the subsequent adsorption of Th(IV). The adsorption experiments were performed by batch-type experiments and include the effect of various physiochemical parameters, as well as characterization of the solid phases by means of spectroscopic (FTIR) and XRD measurements. The experimental data are best described by the pseudo-second order kinetic model (R2 = 0.998) and the adsorbent was found to have a relatively high adsorption capacity (qmax = 70 mg g−1) even at pH 3, attributed to the formation of inner-sphere complexes. 317 2 1065 1070

A coupled experimental investigation and thermodynamic study of the yttrium-hydrogen (Y-H) binary system were carried out to provide more comprehensive and quantitative insights into the key thermodynamic properties of this system. Y-H system in the full range of H/Y = 0–3.0 was investigated by accurate pressure composition isotherm (PCI) measurement to provide credible phase equilibria information and thermodynamic data. The phase boundaries obtained were in agreement with previous experimental data but with improved accuracy. With the guide of the crystal structures, all the solid phases were modelled using the three sublattice model. The Y-H phase diagram and thermodynamic parameters were calculated and assessed with the CALPHAD technique. The obtained results are in very good agreement with our experimental data and the published data reported in literature. The obtained thermodynamic database of Y-H system can be used to predict the hydrogenation behavior and decomposition temperatures of hydrides.

Purpose: Fractal geometry is a relatively young mathematical concept, which has been gradually implemented in various fields of human activity. The focus of this article lies on using this powerful tool for monitoring and forecasting the water solubility of dihydroquercetin (DHQ) and its new forms, which were obtained by lyophilization with different coformers. DHQ, also known as taxifolin, is the major flavonoid of larch wood. This compound prevents the accumulation of free radicals and is characterized by a wide range of pharmacological effects. DHQ is produced industrially and is registered in Russia as an active pharmaceutical ingredient (API). Methods: DHQ co-crystals with different coformers were generated by lyophilization. The fractal dimensions of the lyophilizates were measured by photomicrography processing with special software. The water solubility was determined according to the European Pharmacopoeia 8.0. Results: It was established that the solid phases of the DHQ lyophilizates generate specific structures that agglomerate in different fractals. A correlation was shown between the DHQ fractal dimension and its water solubility. The correlation coefficient was 0.94. The relative standard deviation was no more than 1.17%. Conclusions: This study demonstrated the ability to predict the water solubility of DHQ forms by measurement of the fractal dimensions. The fractal model can find wide application in the pharmaceutical industry as a tool for automating quality assays without substance loss.

This paper presents a topology optimization framework for optimizing the fracture resistance of two-phase composites considering interfacial damage interacting with crack propagation through a redistribution of the inclusions phase. A phase field method for fracture capable of describing interactions between bulk brittle fracture and interfacial damage is adopted within a diffuse approximation of discontinuities. This formulation avoids the burden of remeshing problem during crack propagation and is well adapted to topology optimization purpose. Efficient design sensitivity analysis is performed by using the adjoint method, and the optimization problem is solved by an extended bi-directional evolutionary structural optimization (BESO) method. The sensitivity formulation accounts for the whole fracturing process involving cracks nucleation, propagation and interaction, either from the interfaces and then through the solid phases, or the opposite. The spatial distribution of material phases are optimally designed using the extended BESO method to improve the fractural resistance. We demonstrate through several examples that the fracture resistance of the composite can be significantly increased at constant volume fraction of inclusions by the topology optimization process.

From the condition that the chemical potentials of the components of the AB compoundare equal in the equilibrium liquid and solid phases, taking as pure liquid components as the standardstate, equations are obtained for calculating and modeling of partial excess thermodynamic functions,of the pressure-temperature-composition diagram and liquidus surfaces of the binary compound inthe ternary system A–B–C. The equations obtained are tested on the Cu–Pb–Se system in the liquidusregion of the PbSe compound. It is shown that the vapor phase mainly consists of two atomic moleculesof selenium Se2. For the liquidus regions PbSe(p-type)-Se and PbSe(n-type)-Pb, the followingdependences are obtained, respectively:lg Se p 2 (Pa) = [–1281 + 5624(1000/T) – 9190(1000/T)2 + 6648(1000/T)3 – 1797(1000/T)4] – 10.35 xCu2 ;lg Se p 2 (Pa) = [2026 – 8778(1000/T) + 14247(1000/T)2 – 10259(1000/T)3 + 2759(1000/T)4] – 8.36 xCu2 .For the thermodynamics calculation and modeling of surface crystallization PbSein the ternary systemCu -Pb-Se is obtained dependence:T = [ + ( - x ) Gexs (xl )] / [ . - . ln x ( - Cu.PbSe Se Se 110693 1 0 35D 25 695 8 31 1 xSe )]Where DGexs lPbSe, = –76057 + 335550,738хSe – 2,41759E6хSe2 + 7,33249E6хSe3 – 9,7868E6 хSe4 + 4,69725E6хSe5.3D visualization of the obtained analytical dependencies is carried out with the help of a computerprogram OriginLab2017.

Ternary blends are currently used to improve the properties of Portland cement (PC). In this paper, thermodynamic modelling has been used to analyze the influence of the PC composition on the hydrates formed, in binary and ternary blends with blast furnace slag (BFS), and limestone filler (LF) or fly ash (FA) in order to complement experimental results. Thermodynamic modelling shows that contents of 40–50% of BFS can be optimal in ternary blends with low LF or FA content, and modelling also shows the significant effect of the composition of the PC used in the hydration process of the blends., Authors gratefully acknowledge the Spanish MICINN for the financial support given to this research in BIA2011-22760 project.

Isothermal methods of investigation of quinary systems and advantages of use of the translation method for investigation of quinary water–salt systems were discussed. Two quinary systems—Li, Na, K//CO3, B4O7–H2O and Na, K//Br, SO4, B4O7–H2O—were investigated by means of the translation method at 15 and 25 °C, respectively. The comparison showed a good agreement between our results and the available literature data. There are 4 points, 13 curves, and 15 fields saturated with 4, 3, and 2 different equilibrium solid phases, respectively, in Li, Na, K//CO3, B4O7–H2O systems at 15 °C. The quinary Na, K//Br, SO4, B4O7–H2O system at 25 °C involves 5 invariant points, 16 monovariant curves, and 18 divariant fields saturated with 4, 3, and 2 different equilibrium solid phases, respectively. The total phase equilibria diagrams of both of the quinary systems were constructed on the basis of obtained data. The obtained diagrams were fragmented into divariant cocrystallization fields saturated with two different equil...

Uranium is the most prevalent radioactive element in the 210 million liters of nuclear waste at the Hanford Site but the uranium speciation has not been determined in the waste tanks. The present study determined the common uranium-bearing solid phases in Hanford Site tank waste with X-ray diffraction and scanning electron microscopy. Sodium uranates were the most common species but uranium was also routinely co-precipitated with iron oxides. Na–U–O–P-bearing species were occasionally present. Two morphologies of sodium uranates were observed, long acicular and small spherical agglomerates up to 50 μm in size.

A pressure oxidation (POX)-hot cure (HC)-lime boil (LB) process is used in industry to recover silver from refractory gold sulphide ores containing minerals such as pyrite and arsenopyrite. Pressur...

Removal of microamounts of 60Co and 137Cs from different aqueous solutions, included NPP trap waters and simulated NPP bottom residues, by coprecipitation with various solid phases was studied. It was showed that coprecipitation of 60Co and 137Cs with the solid phase of K+, Fe3+, and Ni2+ ferrocyanides formed by adding K4[Fe(CN)6], Fe(NO3)3, and Ni(NO3)2 ensures almost 100% removal of both radionuclides from simulated NPP trap waters and more than 99% from simulated NPP bottom residue containing simultaneously up to 400 g l−1 NaNO3 and 3.4 × 10−5 mol l−1 EDTA.

Titan's lower atmosphere has condensed phases in equilibrium with it. It is well known that there is a liquid phase in lakes and liquid condensates in the lower troposphere that are part of the liquid cycle in Titan's system. This work analyzes further the phase equilibria using CRYOCHEM equation of state by accounting for solid phases that can exist at the extremely cold conditions on Titan, as well as the possibility of a second liquid phase in the deep lakes, all within the ternary system nitrogen-methane-ethane. Titan's fluid exhibits rich variation of phases that allow us to show multiphase equilibria in full action. The multiphase equilibria covered in this work are two-phase (vapor-liquid, liquid-liquid, solid-liquid, solid-vapor, solid-solid), three-phase (vapor-liquid-liquid, vapor-liquid-solid, vapor-solid-solid, liquid-liquid-solid), and four-phase equilibria (solid-liquid-liquid-vapor); issues associated with the unphysical phases in the calculations are also discussed. The results of multiphase-equilibria analysis describe new understandings about Titan's surface, troposphere, and subsurface lake liquids, as described in the conclusions.

This paper presents a new rolling circle amplification (RCA) technique using stem-loop primers (SLP). The technique enables detection of target DNA by either linear or exponential amplification (SLP-lRCA and SLP-eRCA) in both liquid and solid phases. For solid-phase detection, SLP-eRCA detects nucleic acids in four steps: (1) covalently immobilize an array of capture probes (CP) on a solid support; (2) hybridize the CP array with the DNA sample; (3) incubate the CP array with an RCA reaction containing two SLPs; (4) image the CP array. SLP-eRCA detects nucleic acids in liquid phase in one step: a real-time RCA reaction containing the DNA sample and two SLPs. Both liquid- and solid-phase detection methods employ a general rolling circle and an SLP. The other SLP is specific to the target. The technique was verified by detecting synthesized oligonucleotides and six different human papillomaviruses (HPVs), both in liquid phase and on a solid surface. The technique also detected two high-risk HPVs (HPV16 and HPV18) in cervical carcinoma cells (HeLa and SiHa) and clinical samples. This study provides proof-of-concept for the new RCA technique for nucleic acid detection, which overcomes major limitations of current RCA approaches.

Co-based alloys are key materials for several high temperature applications where high corrosion and wear resistance are required. Main alloying elements, in addition to Co, are Cr, Ni, Ta, Mo, W, Ti, Al, etc. and C. In order to simulate these materials a new thermodynamic database has been implemented which includes the six most important alloying elements: Co, Cr, Ni,Ta, W and C. The liquid and 30 solid phases have been modelled by means of the Compound Energy Formalism (CEF) with particular attention to the consistency between thermodynamic and crystallographic sublattices. Interaction parameters for all the binary and ternary sub-systems are included. When possible they have been taken from the literature but, for several systems, partial or complete reassessment was needed, due to inconsistency of the phase models or incompatibility between assessments of different authors. As a result phase equilibria in selected commercial alloys are calculated.