Unique Mass Research Articles

Black hole-black hole mergers with and without an electromagnetic counterpart: A model for stable tertiary mass transfer in hierarchical triple systems

Triple stars are prevalent within the population of observed stars. Their evolution compared to binary systems is notably more complex and is influenced by unique dynamical, tidal, and mass transfer processes inherent in higher order multiples. Understanding these phenomena is essential for comprehensive insight into multistar evolution and the formation of energetic transients, including gravitational wave (GW) mergers. Our study aims to probe the evolution of triple star systems when the tertiary component fills its Roche lobe and transfers mass to the inner binary. Specifically, we focus on the impact of tertiary mass transfer on the evolution of the inner orbit and investigate whether it could lead to the formation of GW sources with distinct properties. To achieve this, we developed an analytical model that describes the evolution of the inner and outer orbits of hierarchical triples undergoing stable mass transfer from the tertiary component. We have publicly released this model as a python package on Zenodo. Utilising population synthesis simulations, we investigated triples with a Roche-lobe filling tertiary star and an inner binary black hole (BBH). These systems stem from inner binaries experiencing chemically homogeneous evolution (CHE). Our analysis encompasses two distinct populations with metallicities of $Z=0.005$ and $Z=0.0005$, focusing on primary components in the inner binary with initial masses ranging from 20 to $100\ M odot $ and inner and outer orbital separations of up to $40\ R odot $ and $10^5\ R odot $, respectively, targeting the parameter space where chemically homogeneous evolution is anticipated. Our results indicate that for the systems we studied, the mass transfer phase predominantly leads to orbital shrinkage of the inner binary and evolution towards non-zero eccentricities and is accompanied by an expansion of the outer orbit. In the systems where the inner binary components evolve in a chemically homogeneous manner, 9.5<!PCT!> result in mass transfer from the tertiary onto an inner BBH. Within this subset, we predict a high formation efficiency of GW mergers ranging from 85.1<!PCT!> to 100<!PCT!> at $Z=0.005$ and 100<!PCT!> at $Z=0.0005$ with short delay times, partly attributable to the mass transfer phase. Owing to the rarity of triples with a CHE inner binary in the stellar population, we project local merger rates in the range of 0.69 to 1.74 $ Gpc^ $. Of the prospected BBH mergers that enter the LISA and aLIGO frequency band due to GW emission, a fraction is still accreting gas from the tertiary star. This could produce a strong electromagnetic (EM) counterpart to the GW source and maintain high eccentricities as the system enters the frequency range detectable by GW detectors. The occurrence of EM signals accompanying mergers varies significantly depending on model assumptions, with fractions ranging from less than 0.03<!PCT!> to as high as 46.8<!PCT!> of all mergers if the formation of a circumbinary disc is allowed.

Quantum Hall effect in a CVD-grown oxide

Two-dimensional (2D) electron systems are promising for investigating correlated quantum phenomena. In particular, 2D oxides provide a platform that can host various quantum phases such as quantized Hall effect, superconductivity, or magnetism. The realization of such quantum phases in 2D oxides heavily relies on dedicated heterostructure growths. Here we show the integer quantum Hall effect achieved in chemical vapor deposition grown Bi2O2Se - a representative member of a more accessible oxide family. A single or few subband 2D electron system can be prepared in thin films of Bi2O2Se, where the film thickness acts as the key subband design parameter and the occupation is determined by the electric field effect. This oxide platform exhibits characteristic advantages in structural flexibility due to its layered nature, making it suitable for scalable growth. The unique small mass distinguishes Bi2O2Se from other high-mobility oxides, providing a new platform for exploring quantum Hall physics in 2D oxides.

Ultra-inert lanthanide chelates as mass tags for multiplexed bioanalysis

Coordination compounds of lanthanides are indispensable in biomedical applications as MRI contrast agents and radiotherapeutics. However, since the introduction of the chelator DOTA four decades ago, there has been only limited progress on improving their thermodynamic stability and kinetic inertness, which are essential for safe in vivo use. Here, we present ClickZip, an innovative synthetic strategy employing a coordination-templated formation of a 1,5-triazole bridge that improves kinetic inertness up to a million-fold relative to DOTA, expanding utility of lanthanide chelates beyond traditional uses. Acting as unique mass tags, the ClickZip chelates can be released from (biological) samples by acidic hydrolysis, chromatographically distinguished from interfering lanthanide species, and sensitively detected by mass spectrometry. Lanthanides enclosed in ClickZip chelates are chemically almost indistinguishable, providing a more versatile alternative to chemically identical isotopic labels for multiplexed analysis. The bioanalytical potential is demonstrated on tagged cell-penetrating peptides in vitro, and anti-obesity prolactin-releasing peptides in vivo.

Deciphering Isotopic Fine Structures of Silylated Compounds in Gas Chromatography-Vacuum Photoionization Orbitrap Mass Spectrometry of Bio-Oils.

We introduce vacuum resonance-enhanced multiphoton ionization (REMPI) with high-resolution Orbitrap Fourier transform mass spectrometry (FTMS) for analyzing silylated polar compounds. UV laser radiation at 248 nm sensitively and selectively targets aromatic constituents, while high-resolution mass spectrometry (HRMS) enables high-performance mass spectrometric detection. This workflow enhances the detection confidence of polar constituents by identifying unique isotopologue patterns, including at the isotopic fine structure (IFS) level, in analytical standards and complex bio-oils. A direct and derivatized gas chromatography (GC) procedure on a polar standard component mixture allowed us to explore the general ionization and detection characteristics of REMPI FTMS. HRMS enabled the examination of the complex isotopologue profiles, revealing distinct patterns for the CHOxSiy-class compounds. Particularly in complex mixtures, this isobaric/isonucleonic complexity exceeded the classical mass resolution capabilities of the employed Orbitrap D30 series and prompted the usage of prolonged transients via an external data acquisition system. This procedure substantially improved mass spectrometric results by recording the unreduced time-domain transient data for up to 2 s. Notably, the ability to distinguish diagnostic isotopic pairs, such as 12C/29Si vs 13C/28Si with a mass split of ∼3.79 mDa and 13C12C/28Si29Si vs 13C2/28Si2, with an approximate mass difference of ∼3.32 mDa, demonstrates a significant and expected performance improvement. Finally, we benchmark the GC HRMS methodology to identify silylated oxygenated and nitrogen-containing constituents in ultracomplex bio-oil samples. The presented approach of utilizing the silicon isotope pattern and unique isotopologue mass splits for increasing attribution confidence can be applied beyond bio-oils toward the general GC analyses of polar oxygenates.

High quality and sensitivity phononic crystal channel drop filter to detect ethyl lactate in mixtures of ethyl lactate and 2-butoxy ethanol

This paper introduces a new sensing approach utilizing a solid-solid phononic crystal (PnC) channel drop filter structure for the detection of varying molar fractions of Ethyl lactate within a mixture of Ethyl lactate and 2-butoxy ethanol. The sensor features a two-dimensional PnC constructed from poly methyl methacrylate as the background material, incorporating a regular arrangement of circular Tungsten columns. The design integrates a bus waveguide linked to two interconnected ring resonators, which are coupled to a drop waveguide. Each ring resonator is equipped with three strategically positioned pillars near the coupling region, allowing for the accommodation of varying concentrations of Ethyl lactate. The sensor’s performance is significantly influenced by the ring resonators and the integrated pillars. It identifies specific resonance frequencies that shift in response to changes in Ethyl lactate concentrations within the resonators. The transmission resonance frequency exhibits valuable sensitivity to these concentration variations, reflecting the unique sound velocities and mass densities associated with each level of Ethyl lactate. The effectiveness of the proposed sensor is validated through coupled mode theory, demonstrating a close match with the device’s observed behavior. The measured frequency range spans from 1.972 MHz to 1.979 MHz with a step size of 1 Hz. Notably, the sensor displays considerable characteristics, including an average quality factor of 90,613, an average sensitivity of 3816 Hz, an average figure of merit of 172, an average signal-to-noise ratio of 137, an average resolution of 22 Hz, an average damping ratio of 0.56 × 10− 5, and an average limit of detection of 34 × 10− 5. These results underscore the potential of the channel drop filter for the accurate detection of Ethyl lactate concentrations with high quality factor and sensitivity. The sensor can effectively identify variations in Ethyl lactate levels, which are prevalent in various applications, including pharmaceuticals and food additives.

Graphene Oxide and its Composites: Advanced Membranes for Selective Water Permeation.

Graphene oxide (GO) membranes have gained significant attention as a promising material for separation by selective permeation processes due to their advantageous structural and chemical properties, including high water permeability, chemical resistance, and mechanical strength. In this study, we explore the potential applications of GO membranes in pervaporation to separate liquid mixtures. The layered structure and hydrophilic nature of GO membrane facilitate rapid and selective water transport through angstrom-scale interlayer spacings, resulting in superior performance over conventional polymeric and inorganic membranes. The unique mass transport mechanisms - slip flow and molecular alignment - enable GO membranes to selectively permeate water over organic solvents. For chemical dehydration, GO membranes are the most potential candidates. Furthermore, advancements in composite GO membranes and cross-linking techniques that improve their stability and separation performance are discussed. This study highlights the advantages of GO membranes and their potential to replace or complement existing technologies, by emphasizing their role in advancing membrane-based separation and promoting environmental sustainability. Future research is expected to optimize the fabrication techniques for GO membranes and expand their application scope.

B-169 Combining the EXENT System and LC-MS for the Detection of Monoclonal Immunoglobulins at Low Levels

Abstract Background The EXENT® system is an automated platform designed to quantify monoclonal immunoglobulins in serum. EXENT® combines immunoprecipitation and MALDI-TOF mass spectrometry for the detection of monoclonal immunoglobulins at levels lower than traditional gel based methods. This study was designed to demonstrate if EXENT® prepared samples that were negative could be reflexed to a more sensitive method based on capillary flow Liquid Chromatography- Mass Spectrometry (LC-MS) without any modifications to the EXENT® prepared sample. Methods Patient samples containing a monoclonal immunoglobulin (ranging from 20 to 40 g/L) were diluted into pooled polyclonal serum and the samples were prepared and analyzed by EXENT®. Samples that were negative by EXENT® were reflexed by directly loading EXENT® eluates onto the LC-MS instrument. The abundance of the monoclonal immunoglobulin was defined by the signal-to-noise (S/N) of the light chain peak observed after deconvolution. Results Baseline samples were diluted down to two levels, 0.100 g/L and 0.001 g/L. LC-MS detected the same light chain from the monoclonal immunoglobulin as the EXENT® system in all reflexed samples that were negative by EXENT®. Conclusions LC-MS can detect monoclonal immunoglobulins that can no longer be detected using the EXENT® system by tracking the unique molecular mass of the monoclonal light chain. Reflexing samples to LC-MS did not require additional sample handling resulting in a faster time-to-result than current NGS, NGF, and clonotypic peptide approaches. Furthermore, monitoring the intact monoclonal light chain circumvents enzymatic cleavage to create a unique clonotypic peptide, alleviating a situation where no unique peptide can be generated as has been shown previously by Bergen et al. As a consequence, this reflex-methodology results in a consistent way of measuring the presence of malignant B-cells with high sensitivity.

Study of phenanthrenes from their unique mass spectrometric behavior through quantum chemical calculations to liquid chromatographic quantitation

Phenanthrenes and their derivatives have biological relevance owing to their antimicrobial, antioxidant, and cytotoxic effects on cancer cells. They can be efficiently analyzed through ultrahigh-performance liquid chromatography coupled to tandem high-resolution mass spectrometry (UHPLC–MS/HRMS). Herein, we first studied the unique fragmentation behavior of phenanthrenes based on direct infusion MS/HRMS analysis. As a newly described phenomenon, “organ pipe distribution”, we found a structural connection linking their unique fragmentation pattern to serial H radical losses. The bonds responsible for this behavior were identified through quantum chemical calculations using a stepwise approach. Furthermore, the chromatographic aspect of this study was enhanced by developing, validating, and applying a new unscheduled targeted UHPLC–MS/HRMS method for quantifying phenanthrenes in Juncus compressus herb. Targeted compounds were efficiently separated within 4 min upon utilizing the Accucore C30 column, and the unscheduled targeted analytical approach afforded five new isomers. Compounds 1 (effususol), 3 (dehydroeffusol), and 6 (7-hydroxy-1-methyl-2-methoxy-5-vinyl-9,10-dihydrophenanthrene) had their linearity limits determined within 10–5000 nM, and Compounds 2 (effusol), 4 (juncusol), 5 (effususin A), and 7 (compressin A) within 25–5000 nM. The coefficients of variation for precision ranged from 1.4 % to 15.2 %. The obtained matrix effects and accuracy values were also within acceptable ranges. Compounds 2 (effusol) and 3 (dehydroeffusol) were present in both methanolic and dichloromethanolic extracts of Plants 1 and 3 at the highest concentrations. Furthermore, the relationship between phenanthrene fingerprints, obtained through ANOVA statistical analysis of quantitative data, and the geographical location of herbs was also established.

The quality/cosmology tension for a post-inflation QCD axion

It is difficult to construct a post-inflation QCD axion model that solves the axion quality problem (and hence the Strong CP problem) without introducing a cosmological disaster. In a post-inflation axion model, the axion field value is randomized during the Peccei-Quinn phase transition, and axion domain walls form at the QCD phase transition. We emphasize that the gauge equivalence of all minima of the axion potential (i.e., domain wall number equals one) is insufficient to solve the cosmological domain wall problem. The axion string on which a domain wall ends must exist as an individual object (as opposed to a multi-string state), and it must be produced in the early universe. These conditions are often not satisfied in concrete models. Post-inflation axion models also face a potential problem from fractionally charged relics; solving this problem often leads to low-energy Landau poles for Standard Model gauge couplings, reintroducing the quality problem. We study several examples, finding that models that solve the quality problem face cosmological problems, and vice versa. This is not a no-go theorem; nonetheless, we argue that it is much more difficult than generally appreciated to find a viable post-inflation QCD axion model. Successful examples may have a nonstandard cosmological history (e.g., multiple types of cosmic axion strings of different tensions), undermining the widespread expectation that the post-inflation QCD axion scenario predicts a unique mass for axion dark matter.

Enhancing the permeability and selectivity of graphene oxide membrane through polyhedral oligomeric silsesquioxane intercalation for textile wastewater treatment

Graphene oxide-based loose nanofiltration membranes have shown significant potential in nanofiltration processes due to their unique 2D mass transfer nanochannels. However, they still suffer from poor structural stability and overly compact laminar stacking. To address these issues, a novel AP-POSS was intercalated into GO-based membrane to construct a tuned interlayer structure and mass transfer characteristics. The aromatic ring structure of aminophenyl groups on AP-POSS act as hydrophobic side walls of the mass transfer channels between adjacent GO nanosheets, reducing the interaction between water molecules and channel structure. With an optimal amount of AP-POSS as an intercalator, the permeation flux of the prepared POSS-GO membrane could be improved by 30 wt% while maintaining nearly complete rejection of Congo Red (CR). Moreover, the prepared membrane exhibited enhanced structural stability, long-term stability, and a separation factor above 91.0 for CR/NaCl in binary solutions. Our study highlights the excellent performance of the POSS-GO membrane and demonstrates its potential application in dye/salt wastewater treatment.

A Mini Review on the Influence of Different Intermediate Mass Transfer Effects on the Chemical Pretreatment of Lignocellulosic Biomass

ABSTRACTChemical pretreatment of lignocellulosic biomass (LCB) in the presence of an alkaline catalyst is one of the major pretreatment processes that recover cellulose, hemicellulose, and lignin at effective process conditions and also for the production of bioethanol. Replacement of conventional catalysts with waste‐derived catalysts in the pretreatment process will be helpful for the development of low‐cost biorefinery. The continuous impact of different mass transfer properties during the chemical pretreatment of LCB will affect the final yield of products at a high reaction time and has been reviewed in the current study. Intraparticle diffusion of an alkaline catalyst into LCB is going to determine the diffusion of the selected catalyst within the porous biomass structure, which helps in the enhancement of the final yield of the product recovery at low‐process conditions. The diffusion of the synthesized catalyst within the selected biomass during the chemical pretreatment process is a rate‐limiting step that influences the final recovery yield of desired products. Enhancement of the biomass pretreatment reaction through the assessment of the diffusivity using the modified Nernst–Einstein relation is also discussed. Determination of different unique mass transfer properties rate of diffusion, diffusivity flux, and mass transfer coefficient are also to be analyzed to advance the reaction rate of the pretreatment process.

Double Cyclization Tandem Mass for Identification and Quantification of Phosphatidylcholines Using Isobaric Six-Plex Capillary nLC-MS/MS.

Multiplexing of phosphatidylcholine analysis is hindered by a lack of appropriate derivatization. Presented here is a tagging scheme that uses a quaternary amine tag and targets the hydroxy group of the phosphate, which switches the net charge from neutral to +2. Quantitative yields were achieved from >99% reaction completion derived by dimethoxymethyl morpholinium (DMTMM) activation. Fragmentation of phosphatidylcholines (PCs) and lysophosphatidylcholines (LPCs) releases two trimethylamines and the acyl chains through neutral loss and generates a unique double cyclization constant mass reporter. Selective incorporation of isotopes onto the tag produces a six-plex set of isobaric reagents. For equivalent six-plex-labeled samples, <14% RSD was achieved, followed by a dynamic range of 1:10 without signal compression. Quantification of PCs/LPCs in human hepatic cancer cells was conducted as six-plex using data-dependent analysis tandem MS. We report a six-plex qualitative and quantitative isobaric tagging strategy expanding the limits of analyzing PCs/LPCs.

Vertical Characteristic of Water Mass in The Flores Sea: The Effect of The ITF on The Transitional Season

Abstract Indonesian Through Flow (ITF) forms unique water mass characteristics in Indonesian Marine Waters. This water mass enters through the Makassar Strait into the Banda Sea by crossing the Flores Sea. This study aims to analyse the characteristics of water masses in the Flores Sea during the transition season. In situ data was obtained using conductivity temperature depth (CTD) at four stations in the Flores Sea from April to May 2023. Next, the data was processed and analysed for layer thickness through vertical stratification and water mass characteristics using T-S diagrams. The analysis results show that the thickness of the homogeneous layer in the Flores Sea in the first transition season is between a depth of 0-40 m, the thermocline layer is at a depth of 40-300 m, and the depth layer is from a depth of 400-900 m. Apart from that, the characteristics of the water mass identified through the T-S diagram are: North Pacific Subtropical Water (NPSW) is found at a depth of 100-150 m with a temperature between 20-26° C and a salinity between 34.9-35.4 psu. Another water mass is South Pacific Intermediate Water (SPIW) at a depth of 500-800 m with a temperature of 6-8° C and a salinity of 34.55-34.65 psu. In contrast, the Antarctic Intermediate Water (AAIW) was found at a depth of &gt;750 m with a temperature of 5-6° C and a salinity of 34.5-34.6 psu.

Universal Murray’s law for optimised fluid transport in synthetic structures

Materials following Murray’s law are of significant interest due to their unique porous structure and optimal mass transfer ability. However, it is challenging to construct such biomimetic hierarchical channels with perfectly cylindrical pores in synthetic systems following the existing theory. Achieving superior mass transport capacity revealed by Murray’s law in nanostructured materials has thus far remained out of reach. We propose a Universal Murray’s law applicable to a wide range of hierarchical structures, shapes and generalised transfer processes. We experimentally demonstrate optimal flow of various fluids in hierarchically planar and tubular graphene aerogel structures to validate the proposed law. By adjusting the macroscopic pores in such aerogel-based gas sensors, we also show a significantly improved sensor response dynamics. In this work, we provide a solid framework for designing synthetic Murray materials with arbitrarily shaped channels for superior mass transfer capabilities, with future implications in catalysis, sensing and energy applications.

Isolating the Contributions from Moments of Inertia in Isotopic Shifts Measured by High-Resolution Cyclic Ion Mobility Separations.

The unexpected finding that isotopomers (i.e., isotopic isomers) can be separated with high-resolution ion mobility spectrometry-mass spectrometry (IMS-MS) has raised new structural considerations affecting an ion's mobility, namely its center of mass (CoM) and moments of inertia (MoI). Unfortunately, thus far, no studies have attempted to experimentally isolate either CoM or MoI, as they are intrinsically linked by their definitions, where MoI is calculated in relation to CoM. In this study, we designed and synthesized four isotopically labeled tetrapropylammonium (TAA3) ions, each with a unique mass distribution. Three of the synthesized TAA3 ions were labeled symmetrically, thus having identical CoM but differing MoI, which we verified using density functional theory (DFT) calculations. Consequently, we were able to isolate the effect of MoI changes in high-resolution IMS-MS separations. Cyclic ion mobility spectrometry-mass spectrometry (cIMS-MS) separations of the isotopically labeled TAA3 variants revealed isotopic mobility shifts attributable solely to changes in MoI. A 60-m cIMS-MS separation demonstrated that two nominally isobaric TAA3 pseudoisotopomers could be partially resolved, showcasing potential feasibility for isotopomer separations on commercially available IMS-MS platforms. With our previously established collision cross section (CCS) calibration protocol, we also quantified the relationship between MoI and CCS. Our results represent the first demonstration of IMS-MS separations based solely on MoI differences. We believe these findings will contribute important evidence to the growing body of literature on the physical nature of isotopic shifts in IMS-MS separations and work toward more accurate CCS predictions.

Traumatic terson syndrome with a peculiar mass lesion and tractional retinal detachment: a case report

BackgroundTo report a case with bilateral Terson syndrome presented with a unique mushroom-like mass lesion on the optic disc along with proliferative vitreoretinopathy and tractional retinal detachment.Case presentationA 33-year-old man was injured during a traffic accident and had diffuse brain swelling and intraocular hemorrhage. Poor vision in both eyes was noted after the patient regained consciousness. B-scan ultrasonography showed extensive vitreous opacity with a posterior vitreous detachment and without obvious retinal detachment. Vitrectomy was performed in both eyes five months after the accident. After clearing up the vitreous opacity, a peculiar pigmented mushroom-like mass lesion was noted in the posterior pole and had severe adhesion to the underneath optic disc. Extensive multilayered peripapillary epiretinal membrane was found covering the posterior pole and led to tractional retinal detachment around the macula. The mass was presumed to be an organized vitreous hemorrhage originated from the optic disc. The extensive and adherent epiretinal membrane together with the mass lesion were removed as much as possible and silicon oil was injected for tamponade. However, in the right eye, the retina redetached under silicon oil, whereas in the left eye, his vision improved to 20/100.ConclusionsTerson syndrome usually has a favorable prognosis but may be complicated by proliferative vitreoretinopathy and tractional retinal detachment. Careful monitoring is warranted and early vitrectomy should be considered in cases suspecting additional pathologies.

Supersymmetry with scalar sequestering

Supersymmetric models with a strongly interacting superconformal hidden sector (HS) may drive soft supersymmetry (SUSY) breaking scalar masses, bilinear soft term Bμ and Higgs combinations mHu,d2+μ2 to small values at some intermediate scale, leading to unique sparticle mass spectra along with possibly diminished fine-tuning in spite of a large superpotential μ parameter. We set up a computer code to calculate such spectra, which are then susceptible to a variety of constraints: (1) possible charge-or-color breaking (CCB) minima in the scalar potential, (2) unbounded from below (UFB) scalar potential, (3) improper electroweak symmetry breaking, (4) a charged or sneutrino lightest SUSY particle (LSP), (5) generating mh∼125 GeV, (6) consistency with LHC sparticle mass limits, and (7) naturalness. We find this bevy of constraints leaves little or no viable parameter space for the case where hidden sector dynamics dominates minimal supersymmetric standard model (MSSM) running, even for the case of nonuniversal gaugino masses. For the case with moderate HS running with comparable MSSM running, and with universal gaugino masses, then the fine-tuning is ameliorated, but nonetheless remains high. Viable spectra with moderate HS running and with low fine-tuning and large μ can be found for nonuniversal gaugino masses. Published by the American Physical Society 2024

Emulsion synthesis of cellulose/lanthanum alginate /La (Ⅲ) composite microspheres for efficient and selective adsorption of phosphate

Phosphorus exceeding the standard will destroy the ecological environment of the freshwater resources and endanger the survival of aquatic animals. Due to the intrinsic complexation between La(Ⅲ) and alginate, in this study, lanthanum hydroxide was first prepared from lanthanum nitrate, the chemical crosslinking agent was replaced by La(Ⅲ), and cellulose/lanthanum alginate/La(OH)3 composite microspheres (CSPGs-La) were synthesized using polyethyleneimine (PEI) as a crosslinking agent through the emulsification process in one pot. In comparison, the adsorption capacity of 80 mg L−1 PO43− treated with CSPGs-La, CSPGs-Ech (Samples where the chemical crosslinking agent was not replaced by La(Ⅲ)) and La(OH)3 was 159.5 mg g−1, 57.51 mg g−1 and 137.4 mg g−1, respectively. CSPGs-La has good swelling performance, unique three-dimensional structure and mass transfer efficiency, which are the important reasons for its strong ability to capture phosphate. In the presence of coexisting anions, CSPGs-La can still accurately adsorb PO43−, showing good adsorption selectivity. Intra-surface spherical complexation and electrostatic adsorption play an important role. When the dose of CSPGs-La is 1.35 g L−1, the phosphorus pollutants in the actual domestic sewage can be reduced to 10 μg L−1 below. After five adsorption cycles, the retention rate of phosphorus removal performance is 87.7 %. This study provides a green, easy to implement, and promising solution for the preparation of efficient and selective phosphorus removal adsorbent.

Highly Macroporous Polyimide with Chemical Versatility Prepared from Poly(amic acid) Salt-Stabilized High Internal Phase Emulsion Template.

Macroporous polymers have gained significant attention due to their unique mass transport and size-selective properties. In this study, we focused on Polyimide (PI), a high-performance polymer, as an ideal candidate for macroporous structures. Despite various attempts to create macroporous PI (Macro PI) using emulsion templates, challenges remained, including limited chemical diversity and poor control over pore size and porosity. To address these issues, we systematically investigated the role of poly(amic acid) salt (PAAS) polymers as macrosurfactants and matrices. By designing 12 different PAAS polymers with diverse chemical structures, we achieved stable high internal phase emulsions (HIPEs) with >80 vol % internal volume. The resulting Macro PIs exhibited exceptional porosity (>99 vol %) after thermal imidization. We explored the structure-property relationships of these Macro PIs, emphasizing the importance of controlling pore size distribution. Furthermore, our study demonstrated the utility of these Macro PIs as separators in Li-metal batteries, providing stable charging-discharging cycles. Our findings not only enhance the understanding of emulsion-based macroporous polymers but also pave the way for their applications in advanced energy storage systems and beyond.

Recovery of lakes from eutrophication: changes in nitrogen retention capacity and the role of nitrogen legacy in 10 Danish lakes studied over 30 years

AbstractUsing data on 23 Danish lakes, we conducted mass balances to develop total nitrogen (TN) models for predicting annual mean TN in lakes based on external TN loading and found high predictability when including lake hydraulic retention time and mean depth in the model. We further used a unique 30-year mass balance data series from 10 Danish lakes with contrasting mean depths and hydraulic retention times to elucidate the effect of external TN loading reduction and N legacy on lake TN. We found that the TN retention percentage during the 30 years was generally not sensitive to an often major reduction in the external TN loading; it overall followed the pattern of the above model predictions, suggesting a low TN legacy effect. Moreover, the TN retention percentage was not affected by changes in TP. Our results, therefore, show a fast response to TN loading reduction, indicating that we can expect an immediate effect on lake water quality in shallow lakes suffering from internal phosphorus loading during re-oligotrophication provided that inorganic N is low enough to become a growth-limiting nutrient.