Greater Separation Research Articles

Tunable Casimir Equilibria in a Dual-Liquid System

The Casimir effect, a macroscopic manifestation of quantum phenomena, arises from zero-point energy and thermal fluctuations. When two objects are brought into close proximity, the Casimir effect manifests as a repulsive force, while at greater separations, it transitions to an attractive force. There exists a specific distance at which the Casimir force vanishes, referred to as the stable Casimir equilibrium. Stable Casimir equilibria arise from the curve minima of the Casimir energy, which can create spatial trapping. The manipulation of stable Casimir equilibria offers promising applications in areas such as tunable optical resonators and self-assembly. This paper presents a scheme for achieving tunable Casimir equilibria in a dual-liquid system. The system comprises a multilayered stratified structure with a gold substrate. Above the gold substrate, a stratified liquid system is formed due to the immiscibility between organic solutions and water. The lower-density solution is on top, while the higher-density one lies beneath. Our results suggest that a stable Casimir equilibrium for a suspended gold nanoplate can be realized, when the suspended gold nanoplate is immersed in organic solutions of toluene or benzene. Moreover, the height of the suspended gold nanoplate, determined by the stable Casimir equilibrium, can be precisely tuned by varying the thickness of the water layer. The effects of finite temperature and ionic concentration on the Casimir equilibria are also analyzed in this work. The results suggest that the separation heights of Casimir equilibria decrease with increasing the temperature. Interestingly, the ionic concentration in water significantly affects the Casimir pressure when the Debye screening length is comparable or smaller than the separation, allowing for a wide range of modulations on Casimir equilibria. This work opens a new avenue for tuning Casimir equilibria, with significant applications for "quantum trapping" of micro-nano particles.

Controlling Guest Diffusion by Local Dynamic Motion in Soft Porous Crystals to Separate Water Isotopologues and Similar Gases.

ConspectusThe precise and effective separation of similar mixtures is one of the fundamental issues and essential tasks in chemical research. In the field of gas/vapor separation, the size difference among the molecular pairs/isomers of light hydrocarbons and aromatic compounds is generally 0.3-0.5 Å, and the boiling-point difference is generally 6-15 K. These are necessary industrial raw materials and have great separation demands. Still, their separation mainly relies on energy-intensive distillation technology. On the other hand, remarkably similar substances such as oxygen/argon and isotopologues usually exhibit size differences of only 0-0.07 Å and boiling-point differences of only 1-3 K. Although their industrial separation can be realized, their efficiency is considerably low. Therefore, effectively separating remarkably similar mixtures is crucial in fundamental chemistry and industry, but it remains a significant challenge. Porous coordination polymers (PCPs) or metal-organic frameworks (MOFs) are emerging materials platforms for designing adsorbents for separating similar mixtures. However, the reported PCPs did not work well for separating remarkably similar substances. The framework structures of the mainstream PCPs remain unchanged (rigid) or significantly change (globally flexible) upon adsorption. However, rigid and globally flexible PCPs find controlling the pore aperture in subangstrom precision challenging, a prerequisite for distinguishing remarkably similar substances. Thus, novel mechanisms and materials design principles are urgently needed to realize PCPs-based adsorptive separation of remarkably similar mixtures.To confront the obstacles in separating remarkably similar mixtures, our group started contributing to this field in 2017. We employed locally flexible PCPs as the materials designing platform, whose local motions of the side substituent groups potentially regulate the pore apertures to design and control the gas/vapor diffusion in PCPs. Specifically, we encoded dynamic flipping molecular motions into the diffusion-regulatory gate functionality. The ligands were designed by integrating carboxylic coordination groups with nonplanar fused-ring moieties, with the latter moieties exhibiting flipping motion around their equilibrium positions with small energy increases. Such local motions of ligands lead to the dynamic opening and blocking of PCP channels, thus termed flipping dynamic crystals (FDCs). FDCs feature distinctive temperature-responsive adsorption behaviors due to the competition of thermodynamics and kinetics under diffusion regulation, enabling differentiation of remarkably similar mixtures by each gate-admission temperature much higher than the boiling-point temperature of each component. Even when the molecular sizes are the same in the water isotopologue mixtures, FDCs can separate each isotopologue by amplifying their diffusion-rate differences. Finally, by combining the thermodynamic and kinetic factors, FDCs achieve temperature-switched recognition of CO2/C2H2 and diffusion-rate sieving of C3H6/C3H8. Therefore, our work provides a platform for designing locally flexible PCPs by introducing subangstrom precision in flexibility. This opens up the feasibility of separating remarkably similar mixtures on scientific principles. In this Account, we summarize our above ongoing research contributions, including (i) the design of flipping ligands and FDCs, (ii) the characterization of flipping motions, (iii) the gas/isotopologue sorption behaviors, and (iv) the separation of gases and isotopologues. Overall, our studies offer a new aspect of soft porous crystals and provide future opportunities for relevant researchers in this field.

Biomimetic super-wetting membranes via in-situ growth and synchronous integration of ZIF nanoleaves (ZIF-Ls) for emulsified oily wastewater purification and catalytic Knoevenagel condensation

To address the increasingly severe oil spill accidents and water contamination, the development of super-wetting membranes with high oil/water separation efficiency is in great demand but remains challenging. The critical challenge lies in the rational design and fabrication of robust rough surface with hierarchical micro/nano-structure. In this study, biomimetic super-wetting polyacrylonitrile composite membrane was developed through in-situ synthesis and synchronous integration of zeolitic imidazolate framework nanoleaves (ZIF-Ls). Thorough investigation was conducted to assess the effect of the ZIF-Ls growth time on membrane morphology and surface wetting property. Incorporating the nanoleaf-like ZIF-Ls onto the surface of the membrane provided the surface with micro/nano rough structure and superamphiphilic/superlyophobic features. The prepared membrane showed great separation capability toward various O/W and W/O emulsions, and could be easily regenerated by employing a simple rinsing and drying procedure with high separation efficiency sustained even after multiple separation cycles. Moreover, the membrane with ZIF-Ls demonstrated outstanding catalytic performance in the Knoevenagel condensation. This study achieves advancements in the development of super-wettable membranes with outstanding performance in separating emulsions and the as-prepared membranes have the potential to serve as promising candidates for practical oily mixture treatment.

Ultra-fast molecular sieving in ZIF-67 and cellulose nanofibers based thin-film nanocomposite membrane

Membranes based on two-dimensional (2D) materials often show great separation efficiency and therefore have great potential in the treatment of dye wastewater. However, improving the water flux of 2D material-based membranes remains a challenge. In this work, 2D ZIF-67/CNF membranes were prepared on a polyether sulfone (PES) support layer via a simple extraction filtration method. The added CNF intertwined with 2D ZIF-67 nanosheets and formed an interlocked stacked laminar flow structure, which improved both the water flux and stability of the thin-film nanocomposite (TFN) membranes. The optimized membrane showed a water flux of 357.8 L m−2 h−1 bar−1, and its rejections of four dyes (Direct Red 80, Methyl Blue, Alkali Blue 6B and Congo Red) were all above 99.8 %. Furthermore, the optimized membrane maintained a rejection of 97 % after 8 h of continuous operation, indicating that the facile mixing of nanofibers into nanosheets can be considered a promising strategy for preparing TFN membranes for dye wastewater treatment.

Development of a magnetic separation method for rapid isolation and enrichment of bacteria in raw pork using chitosan functionalized magnetic Fe3O4@MIL-100(Fe) composites.

In this study, a pretreatment method based on a magnetic capture probe for the rapid isolation and enrichment of bacteria from raw pork was developed. The chitosan immobilized Fe3O4@MIL-100(Fe) was prepared as a capture probe for total bacterial counts through the electrostatic interaction of positively charged chitosan and the negatively charged substances on the surface of bacteria. The interference of matrix in pork samples on this method was studied and removed by differential centrifugation. The results showed the capture probe had a great selectivity binding and magnetic separation properties for the tested six common bacteria in pork. Under the optimal conditions, the capture efficiency of the bacteria (105 CFU mL-1) from pork surface samples was all above 90%. The capture efficiency of the bacteria in a homogenate system was greatly decreased due to the interference of sarcoplasmic protein and myofibrillar protein in pork. The matrix effect was mitigated by a differential centrifugation method, and the capture efficiency of all six bacteria was >80%. The developed magnetic separation method took 40min and showed good isolation and enrichment properties of bacteria. Thus, the proposed method is expected to provide a simple, convenient, and time-saving pretreatment method for the detection of total bacterial counts in pork.

The sulfurization precipitation and competition mechanisms of Cu(II) and As(V) in electrolyte towards efficient recovery of copper

The sulfide precipitation has been widely used to recover Cu(II) and remove As(V) in copper smelting electrolyte based on the Cu(II)-As(V) separation. However, the recovery efficiency was undesirable due to the inaccurate control of process parameters. It was necessary to investigate the process and mechanisms of sulfurization precipitation for accurate adjustment. Herein, under the single and mixed solutions of Cu(II) and As(V), the process parameters were investigated and the precipitation mechanisms were explored. And when using actual electrolytes, the corresponding sulfurization process and mechanisms were also revealed. The sulfurization results of single component solutions suggested that Cu(II) was rapidly precipitated in one step, but As(V) firstly generated intermediate, then it was gradually reduced to As(III) for a longer time and quickly precipitated in the form of amorphous. This phenomenon caused the significantly faster removal speed of Cu(II) than that of As(V). For their mixed solutions, only a small amount of As(V) were removed by adsorbing the precipitate at the low S/Cu molar ratios (RS/Cu), and Cu(II) and As(V) could achieve a good separation. Simultaneously, it revealed that the sulfidation competitive mechanisms were related to the solubility product constant (Ksp) and initial As(V) concentrations. In addition, the similar rules were also observed in actual electrolytes. Moreover, under RS/Cu = 1.2 and reaction time of 10 min, the arsenic content of sulfide precipitates in the actual electrolyte was less than 2.5%, which showed a great separation also could be obtained for the actual electrolyte. This result met the requirement of Cu(II) recovery. It can provide a good reference for adjusting sulfidation parameters in the actual process to achieve efficient copper recovery, reduce the production of hazardous waste containing arsenic at the source and realize the cleaner production of copper smelting system.

Experimental study and thermodynamic modeling of CO2+CH4 gas mixture hydrate phase equilibria for gas separation efficiency

Gas separation is a critical application of gas hydrates, and accurately predicting separation performance is crucial. In this study, we used thermodynamic calculations to predict the equilibrium phase of gas hydrates for various mole fractions of CO2 + CH4 gas mixtures. We also determined the mole fraction of each gas component trapped within the hydrate clathrate. To predict the equilibrium points, we used the Soave–Redlich–Kwong（(SRK) equation of state for the gas phase, the nonrandom two-liquid (NRTL)model for the liquid phase, and the Chen–Guo model for the hydrate phase. We modified the hydrate fugacity formula and introduced a new function to improve the accuracy of the Chen–Guo model. By incorporating experimental equilibrium results from our study and another study, we developed a correlation based on gas mixture composition and temperature, resulting in highly accurate predictions. The use of this new correlation for hydrate fugacity calculation significantly improved precision, as evidenced by an average absolute deviation percent of calculated pressures (AADP) of 1.34% for pure CO2 and 1.25% for CH4. When considering the 27 data points of different CO2 + CH4 mixtures, the AADP% was 1.98%.To implement the model to predict equilibrium phases, we used the Chen–Guo framework to determine the mole fraction of each gas component in the hydrate mixture. Interestingly, we discovered a linear correlation between the CO2 mole fraction in the hydrate and equilibrium pressure, with a slope of approximately 0.001 and a y-intercept of less than one, for all gas compositions. Therefore, we can conclude that low thermodynamic conditions (temperature and pressure) result in a high CO2 mole fraction in the hydrate phase and great separation efficiency.

Processes of Self‐Management Using Evaluation Based On Distance from Average Solution (EDAS)

People with good self-management skills can effectively regulate and control their feelings, thoughts, and actions in a range of situations. Strong self-management skills allow employees to set goals on their own while making every effort to achieve them. Such employees understand how important it is to control their emotions and behavior at work. Employers like people with high self-management skills since it can be challenging for someone to control their emotions and thoughts. As a result, they might end up shouting at a client and saying harsh things to their coworkers. Self-management skills enable people to exercise more self-control, which leads to wiser professional judgements. Important jobs and activities, as well as fulfilling research goals, call for little diversion and a good capacity for concentration (4). The most crucial tasks are identified, prioritized, and concentrated on by researchers, who also try to avoid distractions. In order to efficiently handle their time, simplify daily tasks, and keep crucial information and things close at hand, researchers create organizational systems. Finally, they get ready to start the job at hand. They arrive early for classes, meetings, and presentations. After leaving for the day, they make plans for the next day. A novel and effective MCDM is designed based on the separation to the mean solution evaluations (EDAS). In this manner, alternatives are chosen depending on how much they deviate analysis, the EDAS approach (Avg evaluation adjusted for distance from solution) is the best choice. The solution with the greatest separation from the ideal is short range and negative, although the comparison between these distances is insignificant. Alternative: Overall sample n 605, 6th graders in 309, 8th graders in 296. Self-management strategies, perceived barriers, Perceived barriers, Outcome expectancy. Results: From the result it is seen that Outcome expectancy is got the first rank where as is the perceived barriers is having the lowest rank.

Preparation of dicationic ionic liquid modified silica stationary phase for mixed-mode liquid chromatography and its application for food additive detection

BackgroundFood safety has become an essential aspect of public concern and there are lots of detection means. Liquid chromatography plays a dominating role in food safety inspection because of its high separation efficiency and reproducibility. However, with the increasing complexity of real samples and monitoring requirements, conventional single-mode chromatography would require frequent column replacement and cannot separate different kinds of analytes on a single column simultaneously, which is costly and time-consuming. There is a great need for fabricating mixed-mode stationary phases and validating the feasibility of employing mixed-mode stationary phases for food safety inspection. ResultsThis work fabricated multifunctional stationary phases for liquid chromatography to determine diverse food additives under the mixed mode of RPLC/HILIC/IEC. Two dicationic ionic liquid silanes were synthesized and bonded onto the silica gel surface. The functionalized silica was characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and elemental analysis. Both columns provide satisfactory separation performance towards 6 hydrophilic nucleosides, 4 hydrophobic polycyclic aromatic hydrocarbons, and 5 anions. Great repeatability of retention (RSD <0.1 %) and column efficiency (100330 plate/m) were obtained. Thermomechanical analysis and linear solvation energy relationship investigated the retention mechanism. Finally, the better in two prepared columns was employed to separate and determine the contents of NO2− and NO3− in vegetables(highest 4906 mg kg−1 NO3− in spinach), preservatives in bottled beverages (180.8 mg kg−1 sodium benzoate in soft drink), and melamine in milk with satisfactory performance and recovery rates ranging from 96.4 % to 105.6 %. SignificanceThis work developed a novel scheme for preparing mixed-mode stationary phases by dicationic ionic liquid which provides great separation selectivity. Most importantly, this work proved the superiority of employing mixed-mode stationary phases for food safety inspection, which might avoid high-cost and frequent changes of columns and chromatography systems in the near future.

Numerical study of the effects of discontinuous ice on three-dimensional wings

Ice accretion has adverse effects on aircraft, so it is very important to study the flow field of iced wings. Unlike previous studies that typically focused on continuous ice, this paper conducts a numerical study of the flow field around discontinuous ice. A modified laminar-turbulent transition model that incorporates large separation correction is employed for the study of discontinuous ice. An iced swept wing was chosen to validate the modified model's capability in predicting aerodynamic performance. The impact of discontinuous ice on both straight and swept wings was studied. For the straight wing, the effect of discontinuous ice with different gap widths on aerodynamic characteristics was investigated. The results show that the reduction in lift caused by discontinuous ice is typically lower than that caused by continuous ice. However, at angles of attack less than 7°, small-gap discontinuous ice causes more substantial reductions in lift compared to continuous ice. This is because small-gap ice causes greater separation at the leading edge, significantly reducing the suction peak of pressure. For the swept wing, the effect of sweep on discontinuous ice was studied. It was found that the swept effect causes asymmetric separation behind the ice shape. At higher angles of attack (greater than 4°), the impact of different ice configurations on lift shows an opposite trend on swept wings compared to straight wings.

Fullerene in Water Remediation Nanocomposite Membranes—Cutting Edge Advancements

Among carbon nanoparticles, fullerene has been observed as a unique zero-dimensional hollow molecule. Fullerene has a high surface area and exceptional structural and physical features (optical, electronic, heat, mechanical, and others). Advancements in fullerene have been observed in the form of nanocomposites. Application of fullerene nanocomposites has been found in the membrane sector. This cutting-edge review article basically describes the potential of fullerene nanocomposite membranes for water remediation. Adding fullerene nanoparticles has been found to amend the microstructure and physical features of the nanocomposite membranes in addition to membrane porosity, selectivity, permeation, water flux, desalination, and other significant properties for water remediation. Variations in the designs of fullerene nanocomposites have resulted in greater separations between salts, desired metals, toxic metal ions, microorganisms, etc. Future investigations on ground-breaking fullerene-based membrane materials may overcome several design and performance challenges for advanced applications.

Construction of adamantane-based monolithic column with three-dimensionally porous structure for small molecules separation and biosample analysis

BackgroundThe fabrication technique of capillary column is the key to the development and application of capillary liquid chromatography (cLC) to improve separation efficiency for analytes. The capillary monolithic column possessed three-dimensionally connected porous or channel structures. Unique porous structure endows excellent permeability and high performance in diverse fields, especially in separation. Thereinto, organic monolithic columns have attracted widespread attention due to their advantages of simple preparation and excellent biocompatibility. However, their separation selectivity needs to be further developed and regulated to apply the separation of more diverse samples. ResultsA novel polymeric monolithic column was prepared via thermally initiated in situ copolymerization of 2-methyladamantan-2-yl acrylate (MADA) with ditrimethylolpropane tetraacrylate (DTTA) in fused silica. The prepared poly(MADA-co-DTTA) monolith showed adjustable permeability, developed porous structure and high thermal stability. Consequently, it exhibited excellent separation capability of small molecules (alkylbenzenes and polycyclic aromatic hydrocarbons). Especially, when acetonitrile/water (60/40, v/v) was used as the mobile phase, the theoretical plate numbers reached 84,000 plates m−1 for butylbenzene at a linear velocity of 0.5 mm s−1. Most importantly, the hydrophobicity of the poly(MADA-co-DTTA) monolithic column was regulated via host-guest interaction between adamantyl group and cucurbit [7]uril (CB[7]). Additionally, the poly(MADA-co-DTTA) monolith was further adopted for the analysis of the tryptic digest of proteins from HeLa by cLC-MS/MS. The 33,783 unique peptides and 5,299 proteins were identified on the monolith, which exhibited great separation ability for complex samples. Significance and noveltyDue to abundant pore structure and good chemical properties, the poly(MADA-co-DTTA) monolithic column exhibited high performance for the separations of small molecules and biological sample. Meanwhile, owing to the existence of adamantyl-group, CB[7] was immobilized on the poly(MADA-co-DTTA) monolithic column to fabricate poly(MADA-co-DTTA)-CB[7] by host-guest interaction. It is possible to adjust the surface chemistry of the monolithic materials to accommodate more complex analytes.

Beat Pilot Tone (BPT): Simultaneous MRI and RF motion sensing at arbitrary frequencies.

To introduce a simple system exploitation with the potential to turn MRI scanners into general-purpose radiofrequency (RF) motion monitoring systems. Inspired by Pilot Tone (PT), this work proposes Beat Pilot Tone (BPT), in which two or more RF tones at arbitrary frequencies are transmitted continuously during the scan. These tones create motion-modulated standing wave patterns that are sensed by the receiver coil array, incidentally mixed by intermodulation in the receiver chain, and digitized simultaneously with the MRI data. BPT can operate at almost any frequency as long as the intermodulation products lie within the bandwidth of the receivers. BPT's mechanism is explained in electromagnetic simulations and validated experimentally. Phantom and volunteer experiments over a range of transmit frequencies suggest that BPT may offer frequency-dependent sensitivity to motion. Using a semi-flexible anterior receiver array, BPT appears to sense cardiac-induced body vibrations at microwave frequencies ( 1.2 GHz). At lower frequencies, it exhibits a similar cardiac signal shape to PT, likely due to blood volume changes. Other volunteer experiments with respiratory, bulk, and head motion show that BPT can achieve greater sensitivity to motion than PT and greater separability between motion types. Basic multiple-input multiple-output ( MIMO) operation with simultaneous PT and BPT in head motion is demonstrated using two transmit antennas and a 22-channel head-neck coil. BPT may offer a rich source of motion information that is frequency-dependent, simultaneous, and complementary to PT and the MRI exam.

A Hydrogel-coated Wood Membrane with Intelligent Oil Pollution Detection for Emulsion Separation.

Considering the potential threats posed by oily wastewater to the ecosystem, it is urgently in demand to develop efficient, eco-friendly, and intelligent oil/water separation materials to enhance the safety of the water environment. Herein, an intelligent hydrogel-coated wood (PPT/PPy@DW) membrane with self-healing, self-cleaning, and oil pollution detection performances is fabricated for the controllable separation of oil-in-water (O/W) emulsions and water-in-oil (W/O) emulsions. The PPT/PPy@DW is prepared by loading polypyrrole (PPy) particles on the delignified wood (DW) membranes, further modifying the hydrogel layer as an oil-repellent barrier. The layered porous structure and selective wettability endow PPT/PPy@DW with great separation performance for various O/W emulsions (≥98.69% for separation efficiency and ≈1000Lm-2h-1bar-1 for permeance). Notably, the oil pollution degree of PPT/PPy@DW can be monitored in real-time based on the changed voltage generated during O/W emulsion separation, and the oil-polluted PPT/PPy@DW can be self-cleaned by soaking in water to recover its separation performance. The high affinity of PPT/PPy@DW for water makes it effective in trapping water from the mixed surfactant-stabilized W/O emulsions. The prepared eco-friendly and low-cost multifunctional hydrogel wood membrane shows promising potential in on-demand oil/water separation and provides new ideas for the functional improvement of new biomass oil/water separation membrane materials.

The Great Separation: Top Earner Segregation at Work in Advanced Capitalist Economies

The Great Separation: Top Earner Segregation at Work in Advanced Capitalist Economies

Next-generation membranes for verapamil removal: Graphene oxide quantum dot-modified polyethersulfone membranes

The presence of verapamil in water sources has gained attention due to its potential risks to ecosystems and human health. Because of its great separation performance and simplicity of integration into existing treatment processes, membrane filtration could be a viable alternative. Polyethersulfone (PES) membrane is usually employed for filtration processes due to its good mechanical and thermal stability. However, pristine PES membrane exhibits low flux and lower fouling properties due to its poor antibacterial properties. Thus, the phase inversion approach was used in the current study to develop graphene oxide quantum dots (GOQDs)-modified PES ultrafiltration (UF) membranes with varying quantities of GOQDs loading (0.01–0.07 wt%). With 0.03 wt% GOQDs, the PES composite membrane exhibited a water flux of 75.23 ±10.43 L/m2 h with a verapamil retention capability of 80.36%. All the modified PES membranes containing GOQDs exhibited the formation of inhibition zones, with PES-0.07 membranes (21.00 mm) showing more pronounced zones. The incorporation of GOQDs proved to be a promising and sustainable approach for modifying PES membranes, enhancing their flux, rejection performance, and antibacterial properties, which could be beneficial in removing pharmaceutical compounds from aqueous solution.

Green Fabrication of Superhydrophilic/Underwater Superoleophobic Composite Membrane for High-Efficiency Oil/Water Separation in Harsh Environments.

Due to the high oil spill incidence and industrial wastewater discharge including oil and emulsified oil, designing and synthesizing oil-water separation materials which can maintain stability under harsh environmental conditions with high separation efficiencies remains a great challenge. The present work developed an easy, green, cost-effective, and easily scaled-up approach for fabricating cellulose-based membranes. First, we coated polydopamine (PDA) onto fibers of filter membrane (FM). Then, the PDA-FM membrane was immersed into the mixed solution of poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA) and further thermally cross-linked at 150 °C to create a superhydrophilic/underwater superoleophobic membrane (PVA/PAA@PDA-FM) to separate oil/water mixtures. The simple thermally cross-linking process promotes multiple covalent chemical bonds generation between cellulose filter membrane, PAA, PDA, and PVA, endowing membranes with excellent stability and resistance to acidity, alkalinity, and salinity. The PVA/PAA@PDA-FM membrane not only demonstrates great separation performance (>99.8%) and great flux (>1000 L m-2 h-1) in oil-water immiscible mixtures but also maintains high separation efficiency under conditions of high acidity, alkalinity, and salinity. Additionally, the PVA/PAA@PDA-FM membrane exhibits excellent separation capacity in oil-water emulsions, which can maintain the >99.6% separation efficiency even after 40 cycles in harsh environments, showing outstanding reusability. Thus, due to the multiple cross-linked networks in the membrane, the excellent performance makes the PVA/PAA@PDA-FM membrane a good application prospect in water purification and oily wastewater treatment.

Emotional Separation among Some Wives in the Municipality of the Capital, Sana’a: An Exploratory Study in Light of the Repercussions of the War for the Period 2015–2023

This study aimed to find out the extent of emotional separation among wives residing in the capital Sana’a in Yemen in light of the repercussions of the ongoing war (2015-2023). The study followed the descriptive approach, and a questionnaire was distributed to a sample of (103) wives in the capital Sana’a who suffer from a case of emotional separation from their husbands. They were chosen randomly. The results indicated moderate levels of emotional separation in multiple axes: (emotional, social, and economic). The psychological and physical axis also came in at a high degree. The husband’s educational level had a significant impact on the degree of separation. Overall and specifically on the “emotional” axis, where the husband’s educational qualifications at the primary level were associated with greater separation, the wife’s economic level also affected the overall grades and on the social, economic, and emotional dimensions, where lower economic status was associated with higher separation. It is worth noting that no differences emerged based on variables, such as: duration of marriage, housing ownership, or work status, but the type of housing (such as living with the husband’s family or a co-wife) showed an association with greater separation on both the economic and psychological-physical levels. Finally, the filial dimension was associated with higher scores on the “emotional” axis.

Diffusion mediated thermally induced phase separation for preparing poly(vinylidene fluoride) membranes with enhanced separation performances

Thermally induced phase separation (TIPS) process is an appealing method for preparing poly(vinylidene fluoride) (PVDF) membranes for separation. In this work, we developed a diffusion mediated thermally induced phase separation (d-TIPS) to prepare PVDF membranes with great molecules separation performances. We investigated the thermodynamics of ternary polymer solutions including PVDF, caprolactam (CPL), and Polyethylene glycol (PEG). We controlled liquid–liquid phase separation and the CPL diffusion by adjusting the addition of PEG and molecular weight to modulate the evolution of morphology from spherulitic to bicontinuous structure. The resulting membrane was characterized by morphology, surface chemistry, tensile strength, water contact angle, and perm-selectivity. The membrane was further stretched for enhanced strength, permeance, and rejection. This work provides a fundamental understanding of the diffusion mediated thermally induced phase separation and shows the great potential of PVDF membranes in macromolecules separation.

Pore size regulation of ZIFs for adsorptive separation of branched chain and aromatic amino acids

AbstractThis research endeavour aims to investigate the adsorptive separation of the branched chain (BCAA) and aromatic amino acids (AAA). Based on the different molecular sizes of BCAA and AAA, zeolitic imidazolate frameworks (ZIFs) with different pore structures were prepared by regulating the size of imidazole ligands. The structure and pore shape were characterized by Fourier transform infrared spectroscopy (FT‐IR), x‐ray diffraction (XRD), scanning electron microscope (SEM), and BET surface area (BET). The results indicated the successful synthesis of ZIF‐[Co(mIm)2], ZIF‐[Co(eIm)2], and ZIF‐[Co(pIm)2] with pore size distribution of 7.821, 6.943, and 9.394 Å, and particle size of these ZIFs was approximately 4 μm. ZIF‐[Co(eIm)2] was chosen as the optimal ZIFs for the separation of BCAA and AAA. The adsorption experiment was evaluated in the respective single and binary systems. The corresponding data in a single system demonstrated that ZIF‐[Co(eIm)2] showed good adsorption performance for BCAA and poor for AAA. Furthermore, the adsorption behaviour under experimental conditions conformed well to the pseudo‐second‐order kinetic model and Langmuir isotherm. ZIF‐[Co(eIm)2] had great separation ability for BCAA/AAA in their binary system. Finally, regeneration studies further manifested that ZIF‐[Co(eIm)2] exhibited fine reusability performance with adsorption efficiencies still higher than 70% after five cycles. This study exhibits a novel path for the design of adsorbents for efficient separation of BCAA/AAA.