Effective Separation Research Articles

Integration of Cu2O-NiTiO3 as an efficient p-n heterojunction visible light photocatalytic system for the simultaneous removal of Cr (VI) and Alizarine Cyanine Green dye

Cu2O loaded NiTiO3 based p-n heterojunction photocatalysts of various proportions have been synthesized by liquid phase reduction process resulting in NiTiO3 nanoparticles dispersed on the surface of Cu2O. Formation of both oxide phases is confirmed from the XRD, HR-SEM and XPS analysis. Heterojunction formation is confirmed by the intimate contact between NiTiO3 and Cu2O as evidenced by HR-TEM. UV-Vis spectra exhibit a red shift indicating the extended visible light absorption. XPS shows the presence of oxidation states of Ni2+, Ti4+, Cu+, Cu2+ and O2-. Heterojunction materials showed enhanced activity for the simultaneous photocatalytic reduction of Cr (VI) and degradation of Alizarine Cyanine Green dye under visible light irradiation. 1:2 ratio of Cu2O and NiTiO3 heterojunction (1C:2N) material exhibits 100% dye degradation in 90 minutes and Cr (VI) reduction in 180 minutes. Higher activity of Cu2O-NiTiO3 p-n heterojunction is ascribed to the effective charge separation and extended visible light absorption

Research on the Separation Technology of Kelp and Shellfish Box Based on Shellfish–Kelp Mixed Culture Mode

Aiming at the problem of floating shellfish boxes interfering with kelp harvesting when mechanized kelp harvesting is based on shellfish–kelp mixed culture mode, this paper combines the structural characteristics of the shellfish box itself, designs the kelp harvesting unit test bench and develops a shellfish box separator device. The key factors affecting the box separator’s separation effect were derived through the theoretical analysis. The process of separation of a shellfish box by the box separator is simulated and optimized under the derived boundary conditions. The single-factor test for the separating effect of the box separator was conducted with ADAMS kinematics simulation software. The test showed the optimal utility intervals for the key factors under consideration. Further orthogonal tests were conducted for the three key factors, which were ranked in descending order of importance as box separator separation angle θ, box separator taper angle β and box separator placement depth h. The optimal parameter combination is the box separator separation angle of 31°, the box separator taper angle of 30° and the box separator placement depth of 550 mm. Verification experiments have shown that both indicators, the farthest horizontal distance of the shellfish box and the angle of the shellfish box deviating from the box separator, meet the actual production requirements. In summary, the separator can effectively separate the shellfish box from the kelp, and the device is simple in design, quick in operation, and accomplished separation without disturbing shellfish. This study can provide a theoretical basis for the separation technology of kelp and shellfish box under shellfish–kelp mixed culture mode.

Vapor separation in minichannel heat sink flow boiling application using gradient porous copper ribs

The accumulation of a significant amount of vapor in minichannels severely limits their flow boiling heat transfer performance, posing a challenge for efficient thermal management in high-power electronic devices. To address this issue, we propose an innovative gradient porous copper rib minichannel with a vapor separation function. This design incorporates micro-pore porous copper and open-cell porous copper, where the unique structure of the micro-pore porous copper is crucial for achieving effective vapor separation. This innovative design not only expands the vapor discharge pathways within the minichannel but also significantly enhances the overall efficiency of vapor removal. Using water as the working fluid, flow boiling experiments were conducted across a range of mass fluxes (G = 26.1 kg/(m2s) ∼ 156.9 kg/(m2s)) and heat fluxes (qeff = 38.2 kW/m2 ∼ 267.5 kW/m2). The experimental results demonstrate that vapor separation significantly alleviates backflow and enhances heat transfer performance. Specifically, our findings indicate that the average temperature of the heat transfer surface decreases by 0 to 10 °C, while the maximum heat transfer coefficient increases by 2.3 times compared to conventional designs. This work presents a practical and innovative approach to mitigating vapor accumulation in minichannels, providing valuable insights for the design of high-performance minichannel heat sinks.

Engineering defect-rich H-W18O49 nanowire/MIL-125(Ti) nanosheet S-scheme heterostructure for remarkable CO2 photoconversion

The rational construction of heterojunctions with surface defects and localized surface plasmon resonance (LSPR) effect is a promising strategy for improving CO2 photoreduction performance. Herein, the one-dimensional/two-dimensional (1D/2D) S-scheme heterostructures integrated with non-stoichiometric 1D W18O49 nanowires (H-W18O49 NWs) and 2D ultrathin MIL-125(Ti) nanosheets (MIL-125(Ti) NSs) were constructed by self-assembly for photocatalytic CO2 reduction. In situ X-ray photoelectron spectroscopy (XPS), electron spin resonance spectra (ESR), and photoluminescence (PL) spectroscopy characterizations confirm the construction of S-scheme heterojunction and the solid internal electric field at the heterointerface enables effective spatial charge separation while keeping a strong redox capability. The hot electrons generated from the LSPR effect of visible-near-infrared light-excited H-W18O49 NWs can be injected into MIL-125(Ti) NSs to increase the electron density and accelerate the reaction rate. Thus, the optimized H-W18O49 NW/MIL-125(Ti) NS heterostructure exhibited good performance, achieving a CO yield of 202.37 μmol g-1h−1. This study enriches the diversity and architecture of available heterostructures for photocatalytic applications.

One-step simultaneous and efficient extraction of multiple active compounds from Lycium barbarum by aqueous three-phase system: Focusing on polysaccharides

In the past few years, the aqueous three-phase system (A3PS) has attracted a lot of attention due to its effectiveness in the efficient separation. Polysaccharides, carotenoids and polyphenols were separated simultaneously from Lycium barbarum by an aqueous three-phase system (A3PS) formed by acetonitrile/betaine/K2HPO4 as a novel extraction technique. The system is characterized by small amount of machine reagents, few consumables and simple extraction steps. The effects of acetonitrile, betaine and K2HPO4 concentrations on the extraction efficiency were investigated by Response Surface Methodology. The optimum composition of A3PS were 26.2 % (w/w) acetonitrile, 10.2 % (w/w) betaine and 27.6 % (w/w) K2HPO4. Under this condition, the extraction efficiencies of carotenoids, polyphenols, and Lycium barbarum polysaccharides (LBP) were 42.12±0.10 %, 88.61±0.95 % and 84.63±0.46 %, respectively. The obtained LBP was characterized by several technologies. The LBP was proved to consist of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose and fucose in a proportion of 4.14:0.80:4.00:4.43:22.20:39.9:12.44:3.22:8.46:0.41. The molecular weight of LBP was 12554 Da. In addition, LBP exhibited excellent antioxidant activity. In general, as a rapid developing method of extraction and separation, A3PS had potential application in the simultaneous separation of multiple substances.

Engineering Trifluoromethyl Groups in Porous Coordination Polymers to Enhance Stability and Regulate Pore Window for Hexane Isomers Separation.

Effective separation of hexane (C6) isomers is critical for a variety of industrial applications but conventional distillation methods are energy-intensive. Adsorptive separations based on porous coordination polymers (PCPs) offer a promising alternative due to their exceptional porosity and tunable properties. However, there is still an urgent need to develop PCPs with high stability and separation performance. This study investigates how substituting a methyl (-CH3) group with a trifluoromethyl (-CF3) group can regulate pores and hydrophobicity in PCPs. This precise adjustment aims to enhance stability and improve the kinetic separation performance of hydrophobic C6 isomers by considering the size and hydrophobicity of the trifluoromethyl group. Two isostructural PCPs with pcu topology, PCP-CH3 and PCP-CF3, were synthesized to vary pore diameters and hydrophobicity based on the presence of -CH3 or -CF3 groups. PCP-CF3 showed greater stability in water compared to PCP-CH3. While PCP-CH3 had high adsorption capacities, it lacked selectivity, whereas PCP-CF3 demonstrated improved selectivity, particularly in excluding dibranched isomers. Dynamic column separation experiments revealed that PCP-CF3 could selectively adsorb linear and monobranched isomers over dibranched isomers at room temperature. These findings highlight the potential of fluorine-modified PCPs for efficient isomer separation and underscore the importance of stability improvement strategies.

3D-micro-flower like [formula omitted] nanoplate solid solution: A facile and rapid room-temperature synthesis with excellent photocatalytic decomposition of antibiotics in water

This research addresses the environmental threat posed by residual antibiotics in water and explores the potential of the photocatalytic process as an eco-friendly solution for antibiotic wastewater treatment. Here in, a series of BiOBr1−xClx nanoplate solid solutions with varied Br:Cl molar ratios were synthesized through a simple co-precipitation method. These solid solutions exhibited superior visible-light-driven photocatalytic activity compared to pristine BiOCl and BiOBr. Notably, the BiOBr0.25Cl0.75 sample demonstrated exceptional performance, achieving 89 % and 99 % degradation efficiency for ciprofloxacin (CIP) and tetracycline hydrochloride (TCH), respectively, within 20 min under optimum conditions. The outstanding performance is attributed to factors such as a large specific surface area, suitable morphology and band gap, effective separation of photo-generated electron-hole pairs, and the presence of meso-size pores in the structure. Thermodynamic studies confirmed the exothermic and spontaneous nature of the photocatalytic reactions. The proposed degradation pathway of CIP and TCH, along with the photocatalytic mechanism, is elucidated. The solid solution, BiOBr1−xClx, exhibits facile recyclability, robust stability, and excellent adaptability to actual aquatic environments, establishing its potential as a promising eco-friendly photocatalyst for antibiotic pollution control.

Enrichment of lithium ions for battery application by electrolysis through a nanoporous membrane

In recent years, lithium (Li) has become a valuable commodity widely used in rechargeable batteries. The present study aims to extract battery-grade lithium-ion, as lithium hydroxide (LiOH), from lithium chloride (LiCl) solution by the membrane electrolysis process. Experiments are performed using a commercial cation exchange membrane and an indigenous High flux-Nanofiltration 300 alkali resistant (HF-NF 300 AR) nanoporous membrane. The dual-chamber electrolytic cell incorporates a selective membrane to separate the feed and concentrate chambers containing LiCl solution and deionized water. These two chambers are connected with titanium electrodes through the external circuit. The in-situ design of the compact two-chambered acrylic electrolytic cell helps to separate metal ions from ionizable salts of sodium, lithium, magnesium, potassium, etc. The experiment is conducted on a laboratory scale by varying the LiCl concentration at voltages of 24 V and 36 V. The feed and concentrate solutions are analyzed for pH, conductivity, and total dissolved solids. Inductively coupled plasma-optical emission spectrometry evaluates the presence of metal ions in the solution. The study shows effective metal ion recovery and separation to achieve battery-grade Li.

ASSESSMENT OF THE PROBABILITY OF OCCURRENCE OF EMERGENCY SITUATIONS DURING OPERATION OF THE PYROLYSIS PLANT

The article discusses the issues of reliability and safety of operation of a pyrolysis plant for the disposal of used tires, which, in the context of an increasing volume of waste and the need for their effective disposal, is an urgent topic. The problem statement is related to the identification of factors affecting the reliability of the installation and the development of methods to prevent emergencies.The purpose of the study is to analyz the reliability of the pyrolysis plant and develop recommendations for its improvement. To achieve this goal, the causes and probabilities of failures of system elements are investigated, an analysis using the failure tree method is carried out. This method made it possible to identify the weaknesses of the system and assess the probability of their failures, which is critical to prevent emergencies.An assessment of the reliability of the installation showed that the greatest contribution to the probability of accidents is made by a malfunction of the gas separation system. This element is the most vulnerable due to its complexity and importance in the pyrolysis process, as it is responsible for the safe and effective separation of pyrolysis products. Any malfunction of the gas separation system can lead to the accumulation of dangerous gases, increasing the risk of explosions and fires. The identified emergencies require special attention to the development of effective measures to minimize them.The article proposes methods to improve the reliability of the system, the main of which is the redundancy of the most vulnerable elements. This will significantly reduce the probability of failures and increase the overall reliability of the installation. In addition, it is recommended to carry out regular inspections and maintenance of all elements of the system. These measures will help to identify and eliminate potential malfunctions in a timely manner, which will significantly reduce the likelihood of failures that can lead to emergencies.Thus, ensuring the reliability and safety of a pyrolysis plant for the disposal of used tires requires an integrated approach. Enabling redundancy of vulnerable elements and regular maintenance will minimize the likelihood of failures that can lead to emergencies and guarantee stable and safe operation of the system. These measures will not only increase the efficiency of disposal, but also ensure reliable and long-term operation of the installation.This article focuses on the importance of identifying vulnerable elements of the system and conducting regular maintenance to improve the reliability and safety of operation of the pyrolysis plant.

Flotation separation of pyrite and carbonate minerals from a carlin-type gold deposit in Guizhou by a new combined collector and its adsorption mechanism

Flotation is the most common method for effective separation of pyrite and carbonate minerals from Carlin-type gold deposits. The effect of conventional xanthate collector on flotation of a Carlin-type gold mine in Guizhou province is poor, and it can not effectively remove carbonate minerals. In this paper, butyl xanthoxanthate and benzohydroxamic acid (BHA) were used as a new combined collector for the flotation separation of a Carlintype gold mine in Guizhou Province. The flotation behavior of pyrite and its adsorption mechanism on pyrite surface were discussed in detail through pure mineral flotation test, actual ore flotation test, contact Angle test, infrared spectrum analysis and XPS analysis. The results showed that the collection capacity of butyl xanthoxime combined with benzohydroxamic acid was obviously stronger than that of BHA or butyl xanthoxime alone. The optimal ratio of pyrite flotation with combined collector is 3, and the recovery rate of pyrite flotation is 37%, which is higher than that of pyrite flotation recovery of 30.5% when benzohydroxamic acid is used alone and 28.5% when butyl xanthate is used alone. The contact Angle test, infrared spectrum and XPS analysis showed that the combined collector of butyl xanthate and benzohydroxamic acid (BHA) produced strong chemical adsorption on the surface of pyrite. Bha can increase the adsorption capacity of butyl xanthate on the surface of pyrite, which is conducive to the flotation recovery of pyrite.

The Throttle Effect in Metal-Organic Frameworks for Distinguishing Water Isotopes.

Metal-organic frameworks (MOFs) have been widely used for separation, but amplifying subtle differences between similar molecules to achieve effective separation remains a great challenge. In this study, we utilize the fluorescent molecule uranine (Ura) to modulate the pores of zeolitic-imidazolate framework 8 (ZIF8), creating an unusual throttle effect. By monitoring fluorescence intensity changes in Ura, the transport diffusion process could be quantified to reveal the diffusion constant of solvents. When we pushed the Ura occupancy to its limit (from 59% to 76% and 98%), the diffusion rate decreases by 2 orders of magnitude. Most importantly, there is a significant dissymmetry between the two-way exchange rates of solvents, and the rates of H2O and D2O became distinguishable. Such unusual throttle effects disappear at low Ura occupancy of 59% and 76%. We believe that the throttle effect with small-molecule loading could provide a universal design principle for MOF-based applications, especially for isotope separation.

Excellent Wavelength Selectivity of p-AlGaN/n-Ga2O3 Solar-Blind UVC PD.

Due to the advantages of ultrawide bandgap, chemical stability, self-powered, and low cost, gallium oxide (Ga2O3) based photodetectors (PDs) are considered as one of the most promising solar-blind ultraviolet PDs, having garnered significant attention in fields such as missile warning and flame arc detection. High selective ratios and excellent responsivity are important to reduce the false alarm rate in solar-blind detection. However, due to the lack of p-type Ga2O3, existing Ga2O3-based PN PDs utilized heterostructures with narrower bandgap p-type semiconductors (e.g., p-GaN, p-SiC, etc.), inducing poor selective ratios with visible light and ultraviolet-A/B (UVA/B). Therefore, a high Al content AlGaN was used in this study to form a p-AlGaN/n-Ga2O3 solar-blind ultraviolet-C (UVC) PD. Since the bandgap of p-AlGaN aligned with the UVC region, the device exhibited exceptionally high selective ratios with R247nm/R360nm = 3.71 × 105 and R247nm/R300nm = 1.47 × 105 at 0 V, which surpassed the reported Ga2O3-based PN PDs. The formation of the type-II heterojunction facilitated the effective separation and transport of photogenerated carriers, resulting in high responsivity (0.36 A/W) under zero bias. Overall, the high selective ratios and high responsivity of the p-AlGaN/n-Ga2O3 PD in this paper provided a reliable pathway for self-powered solar-blind PDs with a low false alarm rate.

Building Asymmetric Zn-N3 Bridge between 2D Photocatalyst and Co-catalyst for Directed Charge Transfer toward Efficient H2O2 Synthesis.

Two-dimensional (2D) polymeric semiconductors are a class of promising photocatalysts; however, it remains challenging to facilitate their interlayer charge transfer for suppressed in-plane charge recombination and thus improved quantum efficiency. Although some strategies, such as π-π stacking and van der Waals interaction, have been developed so far, directed interlayer charge transfer still cannot be achieved. Herein, we report a strategy of forming asymmetric Zn-N3 units that can bridge nitrogen (N)-doped carbon layers with polymeric carbon nitride nanosheets (C3N4-Zn-N(C)) to address this challenge. The symmetry-breaking Zn-N3 moiety, which has an asymmetric local charge distribution, enables directed interfacial charge transfer between the C3N4 photocatalyst and the N-doped carbon co-catalyst. As evidenced by femtosecond transient absorption spectroscopy, charge separation can be significantly enhanced by the interfacial asymmetric Zn-N3 bonding bridges. As a result, the designed C3N4-Zn-N(C) catalyst exhibits dramatically enhanced H2O2 photosynthesis activity, outperforming most of the reported C3N4-based catalysts. This work highlights the importance of tailoring interfacial chemical bonding channels in polymeric photocatalysts at the molecular level to achieve effective spatial charge separation.

Building Asymmetric Zn−N3 Bridge between 2D Photocatalyst and Co‐catalyst for Directed Charge Transfer toward Efficient H2O2 Synthesis

AbstractTwo‐dimensional (2D) polymeric semiconductors are a class of promising photocatalysts; however, it remains challenging to facilitate their interlayer charge transfer for suppressed in‐plane charge recombination and thus improved quantum efficiency. Although some strategies, such as π–π stacking and van der Waals interaction, have been developed so far, directed interlayer charge transfer still cannot be achieved. Herein, we report a strategy of forming asymmetric Zn−N3 units that can bridge nitrogen (N)‐doped carbon layers with polymeric carbon nitride nanosheets (C3N4−Zn−N(C)) to address this challenge. The symmetry‐breaking Zn−N3 moiety, which has an asymmetric local charge distribution, enables directed interfacial charge transfer between the C3N4 photocatalyst and the N‐doped carbon co‐catalyst. As evidenced by femtosecond transient absorption spectroscopy, charge separation can be significantly enhanced by the interfacial asymmetric Zn−N3 bonding bridges. As a result, the designed C3N4−Zn−N(C) catalyst exhibits dramatically enhanced H2O2 photosynthesis activity, outperforming most of the reported C3N4‐based catalysts. This work highlights the importance of tailoring interfacial chemical bonding channels in polymeric photocatalysts at the molecular level to achieve effective spatial charge separation.

Study on the photocatalytic properties of the ternary ZnO/MgAl-LDH/FeOOH composite photocatalyst with a Type-II and S-scheme linked carrier migration mechanism in degrading TC solution

The synthesis of high-performance photocatalysts represents a pivotal aspect of research into photocatalytic degradation technology. In order to address this need, a novel ZnO/MgAl-LDH/FeOOH ternary composite photocatalyst has been synthesized via a multi-step process involving the hydrothermal, calcination and ultrasonic-assisted wet impregnation methods. The ternary composite photocatalyst was observed to demonstrate effective separation of photogenerated carriers in photocatalysis, following a Type-II and S-scheme linked carrier migration mechanism. An examination of the photocatalytic characteristics of the composite photocatalyst in the degradation of a tetracycline (TC) solution revealed that the reduction of •O2- radicals and the oxidation of •OH radicals resulted in the effective degradation of the TC solution. The degradation efficiency of the TC solution under the photocatalysis of the ternary composite photocatalyst was observed to be 1.54, 1.11 and 3.15 times that of the single-component samples of ZnO, MgAl-LDH and FeOOH, respectively, in 30 min. Moreover, the degradation pathway of TC molecules under the photocatalysis of the composite has been elucidated. The research findings provide a foundation for further investigation into this composite photocatalyst.

Indium Oxide Layer Dual Functional Modified Bismuth Vanadate Photoanode Promotes Photoelectrochemical Oxidation of Water to Hydrogen Peroxide.

The photoelectrochemical (PEC) dual-electron pathway for water oxidation to produce hydrogen peroxide (H2O2) shows promising prospects. However, the dominance of the four-electron pathway leading to O2 evolution competes with this reaction, severely limiting the efficiency of H2O2 production. Here, we report a In2O3 passivator-coated BiVO4 (BVO) photoanode, which effectively enhances the selectivity and yield of H2O2 production via PEC water oxidation. Based on XPS spectra and DFT calculations, a heterojunction is formed between In2O3 and BVO, promoting the effective separation of interface and surface charges. More importantly, Mott-Schottky analysis and open-circuit potential measurements demonstrate that the In2O3 passivation layer on the BVO photoanode shifts the hole quasi-Fermi level towards the anodic direction, enhancing the oxidation level of holes. Additionally, the widening of the depletion layer and the flattening of the band bending on the In2O3-coated BVO photoanode favor the generation of H2O2 while suppressing the competitive O2 evolution reaction. In addition, the coating of In2O3 can also inhibit the decomposition of H2O2 and improve the stability of the photoanode. This work provides new perspectives on regulating PEC two/four-electron transfer for selective H2O2 production via water oxidation.

Lysine-regulated turing structure membrane via interfacial polymerization for enhanced Li+/Mg2+ separation

The development of advanced membranes with precise ion selectivity is essential for efficient Li+/Mg2+ separation. In this study, we synthesized a novel Lys-TMC membrane via a nucleophilic addition reaction between Lysine and trimesoyl chloride (TMC), yielding in a negatively charged surface interconnected by amide bonds. We systematically investigated the effects of varying Lys:TMC ratios on the membrane’s chemical structure, surface morphology, and ion separation performance. Our results revealed that the degree of cross-linking increases initially with the Lysine content, reaching an optimum at a Lys:TMC ratio of 10:1, where the membrane exhibited prominent Turing patterns on its surface. These patterns were critical for achieving effective ion separation. In contrast, excessive Lysine led to spontaneous polymerization, resulting in irregular ‘stone-like’ structures and the loss of Turing patterns. The optimally cross-linked Lys-TMC membrane displayed superior Li+/Mg2+ separation performance, highlighting the crucial role of controlled cross-linking and Turing structure formation in enhancing ion selectivity. This work provides a mechanistic understanding of the relationship between Turing structure formation and ion sieving performance, offering a promising strategy for designing advanced separation membranes.

Synergistic enhancement of photocatalytic degradation performance in Cl-g-C3N4/Bi3Al0.06O10 through nitrogen vacancies and S-scheme heterojunctions

The ternary Aurivilius compound BixAlyOz was prepared via a solvothermal technique, with the specific composition determined to be Bi3Al0.06O10 using inductively coupled plasma optical emission spectroscopy. A Cl-g-C3N4/Bi3Al0.06O10 heterojunction was constructed using the solvothermal coprecipitation method. Notably, the introduction of Cl-g-C3N4 with Bi3Al0.06O10 significantly enhanced the decolorization efficiency of both Rhodamine B (RhB) and methylene blue (MB). Specifically, the Cl-g-C3N4/Bi3Al0.06O10 composite with a mass ratio of 1:4 achieved a removal rate of 96.81 % for RhB within 20 min and 96.70 % for MB within 180 min. This is mainly attributed to the synergistic effects of N vacancies and the formation of S-scheme heterojunction in Cl-g-C3N4/Bi3Al0.06O10. These features facilitate the effective separation of photogenerated electrons and holes while expanding the light absorption range. This study not only presents a novel method for synthesizing photocatalysts with N vacancies but also offers a new approach for treating dye-contaminated wastewater.

In situ isotropic 3D imaging of vasculature perfusion specimens using x-ray microscopic dual-energy CT.

Ex vivo x-ray angiography provides high-resolution, three-dimensional information on vascular phenotypes down to the level of capillaries. Sample preparation for ex vivo angiography starts with the removal of blood from the vascular system, followed by perfusion with an x-ray dense contrast agent mixed with a carrier such as gelatine or a polymer. Subsequently, the vascular micro-architecture of harvested organs is imaged in the intact fixed organ. In the present study, we present novel microscopic dual-energy CT (microDECT) imaging protocols that allow to visualise and analyse microvasculature in situ with reference to the morphology of hard and soft tissue. We show that the spectral contrast of µAngiofil and Micropaque barium sulphate in perfused specimens allows for the effective separation of vasculature from mineralised skeletal tissues. Furthermore, we demonstrate the counterstaining of perfused specimens using established x-ray dense contrast agents to depict blood vessels together with the morphology of soft tissue. Phosphotungstic acid (PTA) is used as a counterstain that shows excellent spectral contrast in both µAngiofil and Micropaque barium sulphate-perfused specimens. A novel Sorensen-buffered PTA protocol is introduced as a counterstain for µAngiofil specimens, as the polyurethane polymer is susceptible to artefacts when using conventional staining solutions. Finally, we demonstrate that counterstained samples can be automatically processed into three separate image channels (skeletal tissue, vasculature and stained soft tissue), which offers multiple new options for data analysis. The presented microDECT workflows are suited as tools to screen and quantify microvasculature and can be implemented in various correlative imaging pipelines to target regions of interest for downstream light microscopic investigation.

Innovative discovery on the impact of hydration on the alternative flotation of smithsonite and calcite under benzohydroxamic acid system

Currently, it is still lacking of deep understanding of the alternative of benzohydroxamic acid (BHA) on smithsonite and calcite flotation. We hypothesize that the presence of hydration films plays a significant role. Therefore, this paper aims to uncover the impact of hydration on the alternative flotation of smithsonite and calcite with BHA, utilizing flotation experiments, DFT calculations, Zeta potential tests, FTIR measurements, and XPS analyses. The results of the flotation experiments confirmed the effective separation of smithsonite from calcite with BHA. DFT calculations innovatively discovered that Zn on the surface of smithsonite can interact with BHA− but the Ca on the surface of calcite was easier to interact with the H2O instead of BHA−, thus BHA was incapable of repelling the hydrated layer from the surface of calcite to interact with the calcium ions. Zeta potential tests, FTIR measurements, and XPS analyses further provided experimental support that BHA was selectively chemically adsorbed onto the surface of smithsonite via forming Zn-BHA complex, whereas no such interaction occurred with the surface of calcite by generating Ca-BHA complex, which validated the DFT calculation results. This study provides valuable insights into the role of hydration in the beneficiation of smithsonite and calcite.