Sequential Separation Research Articles

The Fig-Like hierarchical Double-Shelled hollow TiN particles as sulfur host for Lithium-Sulfur batteries

Lithium-sulfur battery(LSB)’s commercial manufacturing has been mainly retarded by the “shuttle effect” and low electrical conductivity of polysulfides (LiPSs). Designing a cathode with hollow and hierarchically porous structures was expected to solve the above problems. Herein, a kind of TiN particles with the hierarchical hollow double-shelled structures was synthesized and applied to cathodes of LSB. The Fig-like hollow TiO2 particles (FHTiO2s) were firstly synthesized by the hard-template method. Subsequently, the Fig-like hierarchical hollow double-shelled TiN particles (FHTiNs) were synthesized by the template-free sequential transformation and separation approach (STSA). It was verified that the heating temperature and time were key parameters. Special Fig-like double-shell hollow structures could greatly increase the loading of S, and the excellent initial capacity of FHTiNs cathodes was up to 1159 mAh/g. On the one hand, the Fig-like framework in internal cavity and double-shell structures could promote the ultrahigh specific surface area, and the adsorption to LiPSs was improved by increasing active sites; On the other hand, the shuttle effect of LiPSs was weakened by the fig-like framework and double-shell structures, which slowed down the massive dissolution of sulfur in the electrolyte. As a result, the pleasant rate performance of FHTiNs cathodes was up to 400 mAh/g at 5C. This novel structures and synthesis method provided a new strategy for the designing of LSB cathodes.

Sequential Separation of Iodine Species in Nitric Acid Media for Speciation Analysis of 129I in a PUREX Process of Spent Nuclear Fuel Reprocessing.

For efficient and accurate speciation analysis of 129I in the nitric acid solution of spent nuclear fuel in its reprocessing process, a sequential procedure for stepwise separation of different iodine species in 3 mol/L HNO3 was proposed based on the solvent extraction using CCl4 and mesitylene. Molecular iodine (I2) was first separated by solvent extraction using CCl4, and iodide (I-) remaining in the aqueous phase was oxidized to I2 by adding NaNO2 and then extracted to mesitylene. Finally, iodate (IO3-) was reduced to I2 using NH2OH·HCl and extracted to mesitylene. The separation efficiency of 98-99% for tracer amounts of 129I2, 129I-, and 129IO3- in 3 mol/L HNO3 and less than 2% crossover among different iodine species were achieved. The extraction process and mechanism of different iodine species in CCl4 and mesitylene were investigated, and the problem of crossover of different iodine species due to the low extraction efficiency of low concentration of iodine in nitric acid solution was solved. A direct transfer of IO3- from HNO3 to the mesitylene phase without conversion to I2 was observed, which was attributed to the iodination of mesitylene in the HNO3 medium. Addition of a stable iodine species carrier and repeated extraction significantly improved the separation efficiency of iodine species, making their quantitative separation achievable. This method provides an approach for speciation analysis of 129I in the acidic spent nuclear fuel solution, enabling us to investigate and control the behavior of volatile 129I in the spent nuclear fuel reprocessing process.

(Invited) Toward Solvent-Based Direct Recycling of Lithium-Ion Batteries

Lithium-ion batteries are booming globally for the applications in electric vehicles, consumer electronics, grid energy storage, and so on. The high demand and production of LIBs drives the generation of vast stockpiles of spent LIBs in near future. Recycling of those waste LIBs not only alleviates the environmental impacts from disposal in landfills and reduces the influences of raw mineral extraction and refining, but also reduces costs and lowers risks of supply chain disruptions. However, the recycling of LIBs is not taking off due to many fundamental and technological challenges. It is thus imperative to develop cost-effective and environmentally sustainable recovery processes to recycle end-of-life batteries. In this context, this presentation highlights the advancements in direct recycling of lithium-ion batteries from different aspects through solvent-based separation and regeneration processes. First, several green solvent-based recovery processes to efficiently separate electrode materials from their current collectors will be presented. Next, an aqueous sequential separation process to separate both anode/cathode and electrode/current collectors will be highlighted. In addition to the solvent-based separation processes, we will discuss the direct regeneration of spent NMC cathode via a solvent-mediated relithiation process. The discussion will shed light on new solvent-based separation and regeneration processes as an enabling step towards direct recycling of LIBs.

Zero valent iron or Fe3O4-loaded biochar for remediation of Pb contaminated sandy soil: Sequential extraction, magnetic separation, XAFS and ryegrass growth

In this study, the feasibility of using zero-valent iron (ZVI) and Fe3O4-loaded biochar for Pb immobilization in contaminated sandy soil was investigated. A 180-day incubation study, combined with dry magnetic separation, chemical extraction, mineralogical characterization, and model plant (ryegrass, namely the Lilium perenne L.) growth experiment was conducted to verify the performance of these two materials. The results showed that both amendments significantly transferred the available Pb (the exchangeable and carbonates fraction) into more stable fractions (mainly Fe/Mn oxides-bound Pb), and ZVI alone showed a better performance than the magnetic biochar alone. The magnetic separation and extended X-ray absorption fine structure (EXAFS) analysis proved that Fe (oxyhydr)oxides on aged ZVI particles were the major scavengers of Pb in ZVI-amended soils. In comparison, the reduced Pb availability in magnetic biochar-amended soil could be explained by the association of Pb with Fe/Mn (oxyhydr)oxides in aged magnetic biochar, also the possible precipitation of soil Pb with soluble anions (e.g. OH−, PO43−, and SO42−) released from magnetic biochar. ZVI increased ryegrass production while Fe3O4-loaded biochar had a negative effect on the ryegrass growth. Moreover, both markedly decreased the Pb accumulation in aboveground and root tissues. The simple dry magnetic separation presents opportunities for the removal of Pb from soils, even though the efficiencies were not high (17.5% and 12.9% of total Pb from ZVI and biochar-treated soils, respectively). However, it should be noted that the ageing process easily result in the loss of magnetism of ZVI while the magnetic biochar tends to be more stable and has high retrievability during the dry magnetic separation application.

Geometry effect in multi-step crossflow microfluidic devices for red blood cells separation and deformability assessment

The efficient separation of blood components using microfluidic systems can help to improve the detection and diagnosis of several diseases, such as malaria and diabetes. Therefore, a novel multi-step microfluidic device, based on passive crossflow filters was developed. Three different designs were proposed, fabricated and tested in order to evaluate the most suitable geometry to perform, simultaneously, blood cells separation and cell deformability measurements. All the proposed geometries include a main channel and three sequential separation steps, all comprised of symmetrical crossflow filters, with multiple rows of pillars, to reduce the amount of red blood cells (RBCs) flowing to the outlets of the microfluidic device (MD). Sets of hyperbolic constrictions located at the outlets allow the assessment of cells deformability. Based on the proposed geometries, the three correspondent MD were evaluated and compared, by measuring the RBCs velocities, the cell-free layer (CFL) effect through the microchannels and by quantifying the amount of RBCs at the outlets. The results suggest that the proposed MD 3 configuration was the most effective one for the desired application, due to the formation of a wider CFL. As a result, a minor amount of RBCs flow through the hyperbolic contraction at the third separation level of the device. Nevertheless, for all the proposed geometries, the existence of three separation levels shows that it is possible to achieve a highly efficient cell separation. If needed, such microdevices have the potential for further improvements by increasing the number of separation levels, aiming the total separation of blood cells from plasma.

Development of a rapid technique for sequential separation of plutonium/americium in nasal swab using solvent extraction and liquid scintillation spectrometry

A rapid radiochemical method has been developed for estimation of plutonium and americium in nasal swab using extractive liquid scintillation spectrometry. The method involves solvent extraction of plutonium and americium from pre-treated nasal swab using 0.2 M Di-(2-ethylhexyl)phosphoricacid prepared in toluene scintillator & back extraction of americium in aqueous phase using 0.35 M HNO3. Activity assessment was carried out using liquid scintillation spectrometry. Overall recovery obtained was 96% for plutonium and 76% for americium with a sample turnaround time of 3 h.

Natural reservoir facial-petroleum field analysis for oil and gas field development

The article describes the method of facies analysis, the relevance of which is determined by the difficulties in the study of genetic spatial heterogeneity of productive natural reservoirs by traditional, mainly "remote" methods, such as geophysical well surveys (GIS) and seismic surveys. In these conditions the facies analysis is of paramount importance: both in traditional for sedimentary strata and in its refined or new modifications. Most often, the sedimentological study uses the developments known as the facies-cyclic analysis, which predetermines a clear methodology of research, providing for a sequential separation of facies - establishment of cycles - correlation of sections - paleogeographic reconstruction, with obligatory "reverse" verification of constructions at each successive stage. However, in today's reality, the classical study of oil and gas exploration and production is practically impossible because of incomplete core sampling, fragmentation of its removal, a priori insufficient amount of core material, especially for unproductive horizons. With the mentioned non-compliance of facies-cyclic "canons" it is suggested to realize direct and direct use of facies studies, realized on the borehole cores for sedimentological and petrophysical modeling of geological natural systems. Thus, consciously removing the problems associated with the allocation of cycles, diachrony of layers of migratory nature, thus having a direct transition to the solution of practical oil and gas problems, based on a reliable facies basis. The method is developed for deep productive horizons, inaccessible to direct observation, in conditions of limited actual data (small number of cores).

Probing the Phytosynthesis Mechanism of Gold and Silver Nanoparticles by Sequential Separation of Plant Extract and Molecular Characterization with Ultra-High-Resolution Mass Spectrometry

Probing the Phytosynthesis Mechanism of Gold and Silver Nanoparticles by Sequential Separation of Plant Extract and Molecular Characterization with Ultra-High-Resolution Mass Spectrometry

Computational study of an integrated microfluidic device for active separation of RBCs and cell lysis

Separation and lysis of RBCs play an important role in diagnosis of different diseases. Although they have been partially studied in several researches, a comprehensive study on integrating both separation and lysis units on a single chip has been seen rarely in the literature. Also, the factors related to the chemical lysis process have not been investigated in detail. In this study, we introduce a novel microfluidic channel design for sequential RBC's separation and lysis. For the separation part, an active method with an electric field was applied to the cells. Besides, a novel mixer was designed for mixing the cell solution and lysis reagent. In the lysis section, we used a mathematical model to simulate cell lysis. It is shown that in electric field with intensity of 2.7 V and frequency of 70 kHz, RBCs are separated with an efficiency of 100%. It is also shown that in using a serpentine mixed with barrier, the mixing efficiency rises to 89.35%. Also, the concentration and volume fraction of lysis reagent were investigated as effecting factors on the cell lysis's efficiency. Based on the results when lysis reagent concentration and volume fraction are 15% and 83.3%, respectively, RBCs are fully lysed.

Simultaneous determination of actinides and 90Sr in large-size soil and sediment samples

A simultaneous analytical method for sequential separation and determination of actinides and 90Sr in large-size environmental samples has been developed. In this method, successive co-precipitation steps were firstly conducted to remove matrix elements, then sequential column separation method was applied for simultaneous separation and purification of actinides and 90Sr/90Y. By using vacuum box technology, the total analytical time was minimized and batch processing allowed analyzing 12 samples in four days. The activity of 90Sr was obtained immediately by measuring its daughter radionuclide (90Y) with triple-to-double coincidence ratio (TDCR) Cherenkov counting, while the concentrations of Pu isotopes and 241Am could be measured by alpha spectrometry and mass spectrometric techniques. The overall recoveries of Pu, Am, Sr and Y were higher than 70% for the entire procedure, while the recovery ratios of Sr/Y were between 0.95 and 1.04 before chromatographic separation. The developed method was verified using 20 g and 50 g of environmental soil samples spiked with certified reference materials IAEA-384 or IAEA-385 and standard solution of 90Sr/90Y, and good agreement between the expected values and measured results has been achieved.

Sequential assembly and separation of synthetic cell models using microfluidics

The emergent field of bottom-up synthetic biology aims to recombine diverse biological systems in artificial cell models for studying complex cellular phenomena in isolation. With dimensions and membrane that resemble biological cells, giant unilamellar vesicles (GUVs) are established as a promising biomimetic compartment for constructing synthetic cells from scratch. However, one of the main reasons that restricts the broad use of GUV-based cell models for studying complex biomolecular systems in vitro, emanates from the inevitable generation of residual components (e.g., surfactants, oil droplets, polymers, nanometric lipid vesicles, etc.) during the formation and manipulation of GUVs.

IMPROVEMENT OF EXPERT RESEARCH OF PRECURSORS BY USING GRAVIMETRIC AND TITRIMETRIC METHODS OF ANALYSIS

The purpose of the article is to develop a technique for determining mass fraction as a necessary and important stage of a reliable forensic assessment of research results based on theoretical generalizations and the practice of complex application of gravimetric and titrimetric methods of analysis using the example of a three-component sulfuric and hydrochloric acids mixture in an aqueous solution. The reliability of the obtained results and conclusions is ensured by the use of general scientific and special research methods. In particular, theoretical methods (analysis, synthesis, comparison, generalization) systematized the materials that constitute the theoretical basis of the study, empirical (observation, measurement, comparison, experiment) experimental studies were conducted to clarify the feasibility of using gravimetric and titrimetric methods of analysis when determining mass particles of inorganic acids. With the help of special statistical and mathematical research methods, both the mass fraction of the constituents of the studied mixtures and the research error were calculated. In general, the application of a complex of methods made it possible to reach a conclusion about the suitability of gravimetric and titrimetric methods of analysis for determining the content of inorganic acids in three-component mixtures. Scientific novelty. The possibility of the complex application of gravimetric and titrimetric methods of analysis to determine the mass fraction of two strong acids (sulfatic and hydrochloric) in an aqueous solution in a three-component mixture is substantiated as a necessary and important stage of a reliable forensic evaluation of research results. Conclusions. Complex application within the experiment of gravimetric and titrimetric methods of analysis to determine the mass fraction in a three-component mixture of two strong acids (sulfate and chloride) in an aqueous solution confirmed the possibility of their use for solving expert tasks. The main advantages of the gravimetric and titrimetric methods of analysis proposed for use are the availability of equipment, simplicity, manufacturability, sufficiently high accuracy, which prove the feasibility of their use for determining individual concentrations of inorganic acids in order to solve the issue of taking measures to control their circulation. The basic principles of the methodology for determining the content of sulfuric and hydrochloric acids in a three-component mixture are outlined, which will serve as a basis for the further development of methodological recommendations in this direction. In addition, the selection of the main parameters of the reagents was carried out and a method was proposed for the quantitative analysis of individual components (inorganic acids) of mixtures (solutions) - sulfuric and hydrochloric acids in a three-component mixture, which is based on their sequential separation and allows obtaining the value of their mass fraction with relative errors 2.4% for sulfate and 4.6% for chloride, which is within the permissible measurement error (Δхmax ≤ 3σ). Keywords: forensic examination; precursors; sulfuric acid; hydrochloric acid; gravimetric method of analysis; titrimetric method of analysis; the mass fraction.

Sequential Separation of Cobalt and Lithium by Sorption: Sorbent Set Selection

Sequential Separation of Cobalt and Lithium by Sorption: Sorbent Set Selection

A New Rising Droplet Non-Equilibrium Extraction Strategy for Sequential Separation of Thulium, Yttrium and Erbium

A New Rising Droplet Non-Equilibrium Extraction Strategy for Sequential Separation of Thulium, Yttrium and Erbium

Active Proteins and Phospholipids Prepared from Chicken Egg Yolk by Green and Efficient Sequential Separation Technology

Active Proteins and Phospholipids Prepared from Chicken Egg Yolk by Green and Efficient Sequential Separation Technology

Multilayer Poly(ionic liquid) Microcapsules Prepared by Sequential Phase Separation and Subsequent Photopolymerization in Ternary Emulsion Droplets

We report a simple microfluidic process to prepare multilayer poly(ionic liquid) (PIL) microcapsules via sequential liquid–liquid phase separation within ternary emulsion droplets followed by the photopolymerization of ionic liquid (IL) monomer-rich phases. Emulsion droplets, consisting of a hydrophobic IL monomer, water, and N,N-dimethylformamide (DMF), are first formed in a microfluidic device, and the droplets are then carried by a continuous aqueous phase. Subsequently, DMF diffuses from the droplets into the continuous aqueous phase, resulting in the sequential internal phase separation of the IL-rich and water-rich phases, generating multilayer emulsion droplets comprising alternating IL-rich and water-rich phases. The number of droplet layers was controlled from one to five by varying the initial composition of the dispersed phase. Furthermore, under the conditions where higher-order emulsion droplets were formed, the time scale between the onset of phase separation and the formation of each layer became shorter. Additionally, the IL-rich phases in the multilayer emulsion droplets were easily solidified via photopolymerization, resulting in PIL microcapsules with multilayer structures. Anion exchange of the obtained PIL microcapsules effectuated their transition from a hydrophobic to a hydrophilic nature, resulting in PIL microcapsules with diverse swelling properties and PIL layer permeability across various solvents. We believe that the sequential phase separation system observed in the ternary emulsion droplets can pave the way for the design of PIL-based colloidal materials with thermodynamically nonequilibrium structures, thereby extending their application in functional materials.

The Intersection of Dementia-Friendly Initiatives and Age-Friendly Environments: The Integration Models

While age friendly city (AFC) initiatives aim to build supportive physical and social environments for older adults, dementia-friendly initiatives (DFI) see the critical need of persons living with dementia (PWD) to be included in society. Given the close relationship between advanced age and dementia risk, communities facing challenges of aging and dementia will benefit from the integration of DFI and AFC. This study aims to summarize the differences between AFC and DFI practice and to identify integrative models for DFI and AFC based upon cases in the U.S.A and China. Qualitative interviews with 11 stakeholders from Massachusetts and Michigan of the U.S.A. and Beijing and Shanghai in mainland China were recorded via Zoom and transcribed for analyses in order to identify different integration models. A summary of differences and commonalities between AFC and DFI core values, key players, major activities, and outcomes is reported. Four practice models of AFC and DFI based upon case analyses were described as sequential integration, concurrent integration, sequential separation, and concurrent separation. Massachusetts’ model is unique in the support from the state government to integrate both from the beginning, and Michigan witnessed separate efforts between grassroots-based agencies and the state government. Shanghai model represents a sequential integration that includes DFI in local government’s long-term aging policy plan, while AFC and DFI in Beijing have a loose connection despite progress made for each initiative. Communities need to develop a practice model considering its local community needs, policy support, and sustainable resources available.

A fast strategy to sequentially separate and determine 90Sr, 210Pb and 210Po in water samples using Sr resin

This study presents a rapid and novel sequential separation strategy based on extraction chromatography for determining 90Sr, 210Pb and 210Po in drinking water samples. It involves the use of Sr resin for the separation and then liquid scintillation counting and alpha spectrometry for the determination. The experimental results obtained showed that the proper acidic solution to quantitatively retain the aforementioned radionuclides is 3 M HNO3. The optimum eluents were determined for obtaining quantitative recoveries (70–80%) of 90Sr, 210Pb and 210Po. The method was validated with intercomparison water samples and is satisfactory in terms of minimum detectable activities, which are 50% lower than that established in RD 314/2016.

What You Extract Is What You Get: Different Methods of Protein Extraction from Hemp Seeds

Cannabis sativa L. seeds are rich in essential polyunsaturated fatty acids and highly digestible proteins, with a good nutritional value. Proteomics studies on hempseed reported so far have mainly been conducted on processed seeds and, to our knowledge, no optimization of protein extraction from hemp seeds has been performed. This study investigates the SDS-PAGE profile of hempseed proteins comparing different methods of extraction, (Osborne sequential extraction, TCA/acetone, MTBE/methanol, direct protein solubilization of defatted hempseed flour), two conditions to keep low temperature during seed grinding (liquid nitrogen or ice) and two solubilization buffers (urea-based or Laemmli buffer). Among the tested conditions, the combination of liquid nitrogen + TCA/acetone + Laemmli buffer was not compatible with SDS-PAGE of proteins. On the other hand, urea-based buffer achieved more reproducible results if combined with all the other conditions. TCA/acetone, MTBE/methanol, and direct protein solubilization of defatted hempseed flour demonstrated a good overview of protein content, but less abundant proteins were poorly represented. The Osborne sequential separation was helpful in diluting abundant proteins thus enhancing the method sensitivity.

Issues of technical implementation of ground-based microwave radiometric system calibration

The theoretical bases of a method of carrying out calibration of microwave radiometric system on a noise signal of the external noise generator are analysed, the parameters setting value of gain of antenna temperature at introduction in structure of system of such external source of a calibration signal are determined. The questions of technical realization of an external source of a calibration signal for microwave radiometric system are considered, the structural scheme is presented, the place of its arrangement in structure of the antenna is determined. The necessity of using a horn antenna to create directional radiation towards the mirror antenna emitter is shown. The data on the design of such a calibration signal source for the case of its use in a three-band microwave radiometric system with the reception of a noise signal at the common antenna aperture and a sequential separation of the input signals of the three bands in the feeder path of the common mirror irradiator are presented. The influence of the design and, accordingly, the directional properties of the horn antenna of a microwave radiometric system calibration signal source on the coefficient characterizing the radiation divergence created by the noise generator horn, as well as the frequency properties of this coefficient are analysed. The results of measurements of radio-thermal radiation by a three-band microwave radiometric system when two calibration periods with reception of a radio-noise signal from an external calibration signal source located at the base of the antenna mirror are presented.