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Silicon–germanium multilayer structures consisting of alternating Si and Ge amorphous nanolayers were annealed by ultrashort laser pulses at near-infrared (1030 nm) and mid-infrared (1500 nm) wavelengths. In this paper, we investigate the effects of the type of substrate (Si or glass), and the number of laser pulses (single-shot and multi-shot regimes) on the crystallization of the layers. Based on structural Raman spectroscopy analysis, several annealing regimes were revealed depending on laser fluence, including partial or complete crystallization of the components and formation of solid Si–Ge alloys. Conditions for selective crystallization of germanium when Si remains amorphous and there is no intermixing between the Si and Ge layers were found. Femtosecond mid-IR laser annealing appeared to be particularly favorable for such selective crystallization. Similar crystallization regimes were observed for both single-shot and multi-shot conditions, although at lower fluences and with a lower selectivity in the latter case. A theoretical analysis was carried out based on the laser energy absorption mechanisms, thermal stresses, and non-thermal effects. [ABSTRACT FROM AUTHOR]

When developping selective crystallization or precipitation processes, biopharmaceutical modalities require empirical screenings and analytics tailored to the specific needs of the target molecule. The multi-way chemometric approach called parallel factor analysis (PARAFAC) coupled with ultraviolet visible light (UV/Vis) spectroscopy is able to predict specific concentrations and spectra from highly structured data sets without the need for calibration samples and reference analytics. These calculated models can provide exploratory information on pure species spectra and concentrations in all analyzed samples by representing one model component with one species. In this work, protein mixtures, monoclonal antibodies, and virus-like particles in chemically defined and complex solutions were investigated in three high-throughput crystallization or precipitation screenings with the aim to construct one PARAFAC model per case. Spectroscopic data sets of samples after the selective crystallization or precipitation, washing, and redissolution were recorded and arranged into a four-dimensional data set per case study. Different reference analytics and pure species spectra served as validation. Appropriate spectral preprocessing parameters were found for all case studies allowing even the application of this approach to the third case study in which quantitative concentration analytics are missing. Regardless of the modality or the number of species present in complex solutions, all models were able to estimate the specific concentration and find the optimal process condition regarding yield and product purity. It was shown that in complex solutions, species demonstrating similar phase behavior can be clustered as one component and described in the model. PARAFAC as a calibration-free approach coupled with UV/Vis spectroscopy provides a fast overview of species present in complex solution and of their concentration during selective crystallization or precipitation, washing, and redissolution.

The management of brines generated from reverse osmosis operation remains a critical challenge requiring new approaches and processes to limit the impact of brine discharge onto ecosystems and to enhance both water and valuable resource recovery. The treatment of real seawater reverse osmosis (SWRO) brines (45,000 ppm TDS) obtained from a local Singaporean desalination plant with a crystallizer integrated pilot-scale membrane distillation unit (MDC) was studied. Commercial STOMATE® hollow fiber membranes were used in vacuum membrane distillation (VMD) configuration, leading to an average flux of around 3.7 L/m2-h at a permeate vacuum of 80 kPa and an average feed temperature of 65 °C. Consistent separation operations were achieved for the treatment of real SWRO brine over a period of 280 h; this led to a water recovery of >95% and to the collection of salt slurries, containing up to ~10–20 wt% of moisture, from the crystallizer. This approach demonstrates the potential of MDC systems to achieve zero brine discharge efficiently from seawater desalination systems, providing an environmentally friendly alternative to manage brines by increasing water recovery and generating salt slurries of economic value.

The impact of two structural factors of sodium carboxylate additives on their ability to induce the selective crystallization of γ‐aminobutyric acid (GABA) Form‐II was investigated, namely, the number of –COO− groups and the types of R groups (chain alkyl, cyclic alkyl, or phenyl). It was found that the increase of –COO− groups caused the additives lose their inducing ability. This may be attributed to the fact that the increment of hydrophilic –COO− groups results in enhanced solvation and steric effect of additives, which makes additives unable to interact with GABA effectively. Additives with different R groups all can induce Form‐II but they exhibited varying inducing abilities. This could be due to the distinct results of competition between the attachment and detachment of different additives on the GABA growth end. [ABSTRACT FROM AUTHOR]

Abstract A green method was proposed for selective crystallization and extraction of suanite crystals from boron bearing slag for ceramics reinforced phase under super-gravity. Through investigating crystallization behavior of boron bearing slag melt, olivine (Mg 2 SiO 4) and suanite (Mg 2 B 2 O 5) crystals were precipitated successively at various temperature ranges of 1623-1473 K and 1473-1323 K. Hence, selective crystallization conditions for the last precipitated suanitie crystals were investigated and two-step separation of suanite crystals from boron bearing slag was conducted in a super-gravity field. Firstly, the mixture of suanite and olivine crystals was separated from slag melt at crystallization temperature of suanite. Subsequently, the molten suanite phase was separated further from olivine crystals at melting temperature of suanite, which precipitated further into suanite crystals after cooling process. Accordingly, high-purity suanite crystals were efficiently attained from boron bearing slag, providing an essential ceramics reinforced phase for ceramic-metallic composite material and glass ceramic. [ABSTRACT FROM AUTHOR]

Abstract A wide variety of brookite TiO 2 synthesis methods have been published over the past several decades, but few studies discuss the underlying mechanism that stabilizes brookite over its stable counterparts, rutile and anatase. Here, we investigate of the effect of pulsed laser deposition parameters on the as-deposited amorphous precursor titania thin films, which subsequently crystallize into stable and metastable TiO 2 polymorphs upon annealing. We find that oxygen pressure in the deposition chamber strongly influences the non-equilibrium state of the amorphous precursor, which ultimately allows for selective polymorph formation. Rutile forms as the dominant phase at low pO 2 < 0.1 mTorr, while anatase is favored at high pO 2 > 5 mTorr. Brookite forms primarily at intermediate pO 2 (0.5–1.0 mTorr). Controlling the amorphous structure (i.e. Ti—O bonding and polyhedral arrangement) of the precursors via oxygen deficiency is therefore likely for the selective formation of crystalline TiO 2 polymorphs from sub-stoichiometric amorphous precursors. Directing phase selectivity by manipulating the structure and internal energy of the precursor amorphous state may have tremendous potential for synthesis of metastable crystalline phases that exhibit more desirable properties in comparison to their stable counterparts. [ABSTRACT FROM AUTHOR]

Simple and effective separation of isomeric organic molecules is an important but challenging task. Herein, we successfully developed a selective crystallization strategy to separate the mixtures of isomeric dicarboxylic acids (DCAs) for the first time. The target DCAs could be preferably combined with crystallization inducer of Zr4+ ions to form a pre‐designed metal‐organic frameworks (MOFs) crystal structure whereas the entry of non‐target isomeric DACs into the MOFs lattice could be exclusively inhibited. Several isomeric pairs were exemplified to verify the extensibility and validity of the developed strategy. iSelect! An extensible strategy has been proposed to separate the mixtures of isomeric dicarboxylic acids by selectively crystallizing the target isomers into a pre‐designed MOFs crystal. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: We present a new method for generating europium oxalate compounds by decomposing of N‐methyl 2‐pyrrolidone in HNO3 media. The reaction exhibits high selectivity towards Eu3+ over UO22+, which suggests that these conditions could be applied to a selective crystallization based separation system for trivalent lanthanides and hexavalent actinides. In this work, a new method for the separation of trivalent Eu3+ and hexavalent UO22+ in initial high‐acidity HNO3 solution is presented. N‐Methyl 2‐pyrrolidone was added in the HNO3 solution where Eu3+ and UO22+ coexisted, then the solution was heated. Eu3+ will react with oxalic acid and dimethylamine produced by N‐methyl 2‐pyrrolidone and form compound NH2(CH3)2[Eu(C2O4)2(H2O)], while UO22+ remains in the solution. This method provide a new strategy for separation of trivalent Eu3+ and hexavalent UO22+. [ABSTRACT FROM AUTHOR]

• Crystallization of Ge/Si multilayer stacks is investigated using ultrashort pulse IR lasers. • Selective crystallization of a-Ge layers is achieved without intermixing with Si. • Conditions of selective crystallization have been determined. • Mechanisms of crystallization are revealed through rigorous theoretical analysis. Pulsed laser crystallization is an efficient annealing technique to obtain polycrystalline silicon or germanium films on non-refractory substrates. This is important for creating "flexible electronics" and can also be used to fabricate thin-film solar cells. In this work, near- and mid-infrared femtosecond and picosecond laser pulses were used to crystallize a Ge/Si multilayer stack consisting of alternating amorphous thin films of silicon and germanium. The use of infrared radiation at wavelengths of 1030 and 1500 nm with photon energies lower than the optical absorption edge in amorphous silicon allowed obtaining selective crystallization of germanium layers with a single laser shot. The phase composition of the irradiated stack was investigated by the Raman scattering technique. Several non-ablative regimes of ultrashort-pulse laser crystallization were found, from partial crystallization of germanium without intermixing the Ge/Si layers to complete intermixing of the layers with formation of Ge x Si 1-x solid alloys. The roles of single- and two-photon absorption, thermal and non-thermal (ultrafast) melting processes, and laser-induced stresses in selective pico- and femtosecond laser annealing are discussed. It is concluded that, due to a mismatch of the thermal expansion coefficients between the adjacent stack layers, efficient explosive solid-phase crystallization of the Ge layers is possible at relatively low temperatures, well below the melting point. [ABSTRACT FROM AUTHOR]

• MIL-100 materials were successfully based on stainless steel pickling wastewater. • The products exhibit high stability, porosity and excellent adsorption performances. • The nickel in the wastewater was largely purified up along with MOF synthesis. • The cost of MOFs was reduced due to the use of industrial wastewater. Metal-organic frameworks (MOFs) exhibit large potential in many fields while the high cost limits their large-scale use. Herein, stainless steel pickling wastewater was successfully transformed to Fe/Cr-MIL-100, during which Ni2+ was largely purified. As an integration of metal, solvent and acid modifier, the use of the wastewater simplifies the preparation units and reduces the cost of MOFs. Conversion of the pickling wastewater to MOFs is feasible under wide reaction conditions and is not interfered by discharge batch of the wastewater. The obtained MIL-100 s products exhibit excellent porosity, long-term acid/base stability, and large adsorption capacities for methylene blue, moxifloxacin hydrochloride, and zirconium (IV) ion. Thus, our work provides a new insight for effective reuse of industrial wastewater and a feasible method for reducing MOFs cost. [Display omitted] [ABSTRACT FROM AUTHOR]

Presented here are two isostructural uranyl coordination polymers [UO(EDO)(HO)]·HO ( 1) and [UO(BDO)(HO)]·2HO ( 2) (EDO=ethylene-1,2-dioxamate; BDO=butylene-1,2-dioxamate) with identical stepwise zigzag chain structure and distinct interchain hydrogen bonding interaction, prepared from hydrothermal reaction of DEEDO or DEBDO (DEEDO=diethyl ethylene-1,2-dioxamate; DEBDO=diethyl butylene-1,2-dioxamate) with uranyl ions. The monomeric uranyl-based fluorescence emissions of compounds 1 and 2 are red-shifted by about 6 and 5 nm respectively, compared to that of uranyl nitrate hexahydrate. Compound 1 has stronger emission than compound 2, but both their emissions exhibit triple-exponential decay. The photophysics of uranyl oxalate trihydrate was also investigated for comparison. The selective crystallization of compound 1 in alkaline solution was applied to the sequestration of uranyl ions, showing a kinetic preference. [ABSTRACT FROM AUTHOR]

The separation of cadmium and nickel from sulfate leach liquors of waste Ni–Cd batteries is investigated by using ternary phase diagrams. Experimental studies are carried out to obtain ternary phase diagrams of nickel sulfate, cadmium sulfate and water mixture at 40 °C and 80 °C. The eutectic point is determined to be composed of CdSO 4 .8/3H 2 O + NiSO 4 .6H 2 O and CdSO 4 .H 2 O + NiSO 4 .6H 2 O, for 40 °C and 80 °C, respectively, while two univariant curves and two crystallization regions are observed corresponding to CdSO 4 .8/3H 2 O and NiSO 4 .6H 2 O at 40 °C, CdSO 4 .H 2 O and NiSO 4 .6H 2 O at 80 °C. Both low (40 °C) and high (80 °C) temperature systems belong to a simple saturated type while no double salts or solid solutions exist. [ABSTRACT FROM AUTHOR]

When developping selective crystallization or precipitation processes, biopharmaceutical modalities require empirical screenings and analytics tailored to the specific needs of the target molecule. The multi-way chemometric approach called parallel factor analysis (PARAFAC) coupled with ultraviolet visible light (UV/Vis) spectroscopy is able to predict specific concentrations and spectra from highly structured data sets without the need for calibration samples and reference analytics. These calculated models can provide exploratory information on pure species spectra and concentrations in all analyzed samples by representing one model component with one species. In this work, protein mixtures, monoclonal antibodies, and virus-like particles in chemically defined and complex solutions were investigated in three high-throughput crystallization or precipitation screenings with the aim to construct one PARAFAC model per case. Spectroscopic data sets of samples after the selective crystallization or precipitation, washing, and redissolution were recorded and arranged into a four-dimensional data set per case study. Different reference analytics and pure species spectra served as validation. Appropriate spectral preprocessing parameters were found for all case studies allowing even the application of this approach to the third case study in which quantitative concentration analytics are missing. Regardless of the modality or the number of species present in complex solutions, all models were able to estimate the specific concentration and find the optimal process condition regarding yield and product purity. It was shown that in complex solutions, species demonstrating similar phase behavior can be clustered as one component and described in the model. PARAFAC as a calibration-free approach coupled with UV/Vis spectroscopy provides a fast overview of species present in complex solution and of their concentration during selective crystallization or precipitation, washing, and redissolution., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wegner and Hubbuch.)

The management of brines generated from reverse osmosis operation remains a critical challenge requiring new approaches and processes to limit the impact of brine discharge onto ecosystems and to enhance both water and valuable resource recovery. The treatment of real seawater reverse osmosis (SWRO) brines (45,000 ppm TDS) obtained from a local Singaporean desalination plant with a crystallizer integrated pilot-scale membrane distillation unit (MDC) was studied. Commercial STOMATE® hollow fiber membranes were used in vacuum membrane distillation (VMD) configuration, leading to an average flux of around 3.7 L/m2-h at a permeate vacuum of 80 kPa and an average feed temperature of 65 °C. Consistent separation operations were achieved for the treatment of real SWRO brine over a period of 280 h; this led to a water recovery of >95% and to the collection of salt slurries, containing up to ~10−20 wt% of moisture, from the crystallizer. This approach demonstrates the potential of MDC systems to achieve zero brine discharge efficiently from seawater desalination systems, providing an environmentally friendly alternative to manage brines by increasing water recovery and generating salt slurries of economic value.

It is very rare that a one-step process of extraction leads to the pure compound with a high degree of purity specified by an industrial application. The various stages of a synthesis process and possible secondary reactions may lead to the synthesis of more or less complex and highly diluted solutions. In this work, the rationale and strategy for extraction and purification of a high added value compound are discussed. All the thinking is based on the knowledge and the exploitation of phase diagrams and then developed for different unit operations of the process. The most significant research tools are the experimental data and the modelling of phase equilibrium to estimate the yield of each step of extraction. The significant example chosen involves all the basic methods of phase separation, starting with liquid-vapour equilibrium: stripping of high volatility components and then more or less complex distillation are classically employed. The theoretical plateau number can be deduced from the equilibrium equation curves. The second step is based on the study of the liquid-liquid equilibrium and is an intermediate step for enrichment of the solution when distillation is not possible. A final step based on solid-liquid equilibrium consists of the selective crystallization of the pure product at low temperature, in order to satisfy the requirements of purity and safety imposed by industrial use. The conclusion includes all isolation operations in the form of a general extraction and purification scheme. [ABSTRACT FROM AUTHOR]

Crystallization and immobilization of actinides to form actinide compounds are of significant importance for the extraction and reutilization of nuclear waste in the nuclear industry. In this paper, the state-of-art progress in the crystallization of actinides are summarized, as well as the main functionalization of the actinide compounds, i.e., as adsorbents for heavy metal ions and organic pollutant in waste management, as (photo)catalysts for organic degradation and conversion, including degradation of organic dyes and antibiotics, dehydrogenation of N-heterocycles, CO 2 cycloaddition, selective alcohol oxidation and selective oxidation of sulfides. This review will give a comprehensive summary about the synthesis and application exploration of solid actinide crystalline salts and actinide-based metal organic frameworks in the past decades. Finally, the future perspectives and challenges are proposed in the end to give a promising direction for future investigation. [Display omitted] • Overview of the separation of actinides by selective crystallization method. • The synthesis and fundamental properties of various actinide compounds were reviewed in detail. • Research progress in the functionalization of actinide compounds were exhibited here. • Put forward the difficulties that need to be paid attention to in further research. [ABSTRACT FROM AUTHOR]

Four triglyceride fats and oils (beef tallow, lard, rapeseed oil and soybean oil) were reacted with glycerol while using lipase as the catalyst. For all fats examined, at reaction temperatures above the critical temperature (T), the fatty acid compositions of the monoglyceride (MG) and diglyceride (DG) fractions and of the original fat were similar. A relatively low yield of MG was obtained (20-30 wt%). When the reaction was carried out with beef tallow or lard at a temperature below the T (40°C), the concentration of saturated fatty acids in the MG fraction was 2 to 4 times greater than that in the DG fraction. Correspondingly, the concentration of unsaturated fatty acids in the DG fraction was more than two times greater than that in the MG fraction. At 5°C, a similar trend was observed for rapeseed oil and soybean oil. Direct analysis of partial glycerides during glycerolysis by high-temperature gas-liquid chromatography showed that below T the content of C16 MG increased relatively more than C18 MG. C36 DG and C54 TG were apparently resistant to glycerolysis. Preferential distribution of saturated fatty acids into the MG fraction was accompanied by a high yield of monoglyceride (45-70 wt%) and solidification of the reaction mixture. It is concluded that during glycerolysis below T, preferential crystallization occurs for MGs that contain a saturated fatty acid. [ABSTRACT FROM AUTHOR]