Scalable and Highly Porous Membrane Adsorbents for Direct Air Capture of CO2.

Direct air capture (DAC) of CO2 is a carbon-negative technology to mitigate carbon emissions, and it requires low-cost sorbents with high CO2 sorption capacity that can be easily manufactured on a large scale. In this work, we develop highly porous membrane adsorbents comprising branched polyethylenimine (PEI) impregnated in low-cost, porous Solupor supports. The effect of the PEI molecular mass and loading on the physical properties of the adsorbents is evaluated, including porosity, degradation temperature, glass transition temperature, and CO2 permeance. CO2 capture from simulated air containing 400 ppm of CO2 in these sorbents is thoroughly investigated as a function of temperature and relative humidity (RH). Polymer dynamics was examined using differential scanning calorimetry (DSC) and broadband dielectric spectroscopy (BDS), showing that CO2 sorption is limited by its diffusion in these PEI-based sorbents. A membrane adsorbent containing 48 mass% PEI (800 Da) with a porosity of 72% exhibits a CO2 sorption capacity of 1.2 mmol/g at 25 °C and RH of 30%, comparable to the state-of-the-art adsorbents. Multicycles of sorption and desorption were performed to determine their regenerability, stability, and potential for practical applications.

Heavy Metal Remediation by Dry Mycelium Membranes: Approaches to Sustainable Lead Remediation in Water.

Lead contamination poses significant and lasting health risks, particularly in children. This study explores the efficacy of dried mycelium membranes, distinct from live fungal biomass, for the remediation of lead (Pb(II)) in water. Dried mycelium offers unique advantages, including environmental resilience, ease of handling, biodegradability, and mechanical reliability. The study explores Pb(II) removal mechanisms through sorption and mineralization by dried mycelium hyphae in aqueous solutions. The sorption isotherm studies reveal a high Pb(II) removal efficiency, exceeding 95% for concentrations below 1000 ppm and ∼63% above 1500 ppm, primarily driven by electrostatic interactions. The measured infrared peak shifts and the pseudo-second-order kinetics for sorption suggests a correlation between sorption capacity and the density of interacting functional groups. The study also explores novel surface functionalization of the mycelium network with phosphate to enhance Pb(II) removal, which enables remediation efficiencies >95% for concentrations above 1500 ppm. Scanning electron microscopy images show a pH-dependent formation of Pb-based crystals uniformly deposited throughout the entire mycelium network. Continuous cross-flow filtration tests employing a dried mycelium membrane demonstrate its efficacy as a microporous membrane for Pb(II) removal, reaching remediation efficiency of 85-90% at the highest Pb(II) concentrations. These findings suggest that dried mycelium membranes can be a viable alternative to synthetic membranes in heavy metal remediation, with potential environmental and water treatment applications.

Membrane Separation Technology in Direct Air Capture.

Direct air capture (DAC) is an emerging negative CO2 emission technology that aims to introduce a feasible method for CO2 capture from the atmosphere. Unlike carbon capture from point sources, which deals with flue gas at high CO2 concentrations, carbon capture directly from the atmosphere has proved difficult due to the low CO2 concentration in ambient air. Current DAC technologies mainly consider sorbent-based systems; however, membrane technology can be considered a promising DAC approach since it provides several advantages, e.g., lower energy and operational costs, less environmental footprint, and more potential for small-scale ubiquitous installations. Several recent advancements in validating the feasibility of highly permeable gas separation membrane fabrication and system design show that membrane-based direct air capture (m-DAC) could be a complementary approach to sorbent-based DAC, e.g., as part of a hybrid system design that incorporates other DAC technologies (e.g., solvent or sorbent-based DAC). In this article, the ongoing research and DAC application attempts via membrane separation have been reviewed. The reported membrane materials that could potentially be used for m-DAC are summarized. In addition, the future direction of m-DAC development is discussed, which could provide perspective and encourage new researchers' further work in the field of m-DAC.

Synthesis and superconductivity in yttrium-cerium hydrides at high pressures.

Further increasing the critical temperature and/or decreasing the stabilized pressure are the general hopes for the hydride superconductors. Inspired by the low stabilized pressure associated with Ce 4f electrons in superconducting cerium superhydride and the high critical temperature in yttrium superhydride, we carry out seven independent runs to synthesize yttrium-cerium alloy hydrides. The synthetic process is examined by the Raman scattering and X-ray diffraction measurements. The superconductivity is obtained from the observed zero-resistance state with the detected onset critical temperatures in the range of 97-141 K. The upper critical field towards 0 K at pressure of 124 GPa is determined to be between 56 and 78 T by extrapolation of the results of the electrical transport measurements at applied magnetic fields. The analysis of the structural data and theoretical calculations suggest that the phase of Y0.5Ce0.5H9 in hexagonal structure with the space group of P63/mmc is stable in the studied pressure range. These results indicate that alloying superhydrides indeed can maintain relatively high critical temperature at relatively modest pressures accessible by laboratory conditions.

Low-Loading Mixed Matrix Materials: Fractal-Like Structure and Peculiarly Enhanced Gas Permeability.

Mixed matrix materials (MMMs) containing metal-organic framework (MOF) nanoparticles are attractive for membrane carbon capture. Particularly, adding <5 mass % MOFs in polymers dramatically increased gas permeability, far surpassing the Maxwell model's prediction. However, no sound mechanisms have been offered to explain this unusual low-loading phenomenon. Herein, we design an ideal series of MMMs containing polyethers (one of the leading polymers for CO2/N2 separation) and discrete metal-organic polyhedra (MOPs) with cage sizes of 2-5 nm. Adding 3 mass % MOP-3 in a polyether increases the CO2 permeability by 100% from 510 to 1000 Barrer at 35 °C because of the increased gas diffusivity. No discernible changes in typical physical properties governing gas transport properties are detected, such as glass transition temperature, fractional free volume, d-spacing, etc. We hypothesize that this behavior is attributed to fractal-like networks formed by highly porous MOPs, and for the first time, we validate this hypothesis using small-angle X-ray scattering analysis.

Patient Versus Physician Perspective in the Management of Chronic Myeloid Leukemia During Treatment with Tyrosine Kinase Inhibitors.

INTRODUCTION: Chronic myeloid leukemia (CML) is a chronic disease with treatment-free remission (TFR) increasingly regarded as a feasible goal of treatment. However, various factors may influence adherence to international guidelines for CML management. This study aimed to compare the reporting of care between patients with CML and their treating doctors. METHODS: Parallel patient and physician online surveys were conducted between September 22, 2021, and March 15, 2022, which focused on the perceptions of 1882 adult patients with CML and 305 physicians regarding tyrosine kinase inhibitor (TKI) treatment options, monitoring and toxicities, TFR, and challenges faced. RESULTS: Among the enrolled patients, 69.9% received first-line imatinib treatment, 18.6% received nilotinib, and 4.7% received dasatinib. Among the patients treated with imatinib, 36.7% switched to other TKIs due to imatinib resistance/intolerance (71.1%), exploration of more potent TKIs to achieve TFR (8.9%), and treating physicians' recommendation (14.0%), with a median duration of initial treatment of 14 months [interquartile range (IQR) 6-36]. Most (91.8%) physicians agreed that the breakpoint cluster region-Abelson 1 (BCR::ABL1) transcript level should be assessed every 3 months, but only 42.7% of individuals committed to 3-monthly testing and only 17.8% strictly followed their treating physicians' recommendation. Half of the patients aimed for TFR; however, just 45.2% of physicians considered TFR as one of the top three goals for their patients. The major concern in obtaining TFR was patients' adherence. Fatigue was often distressing for patients with TKIs, while physicians were more concerned about platelet and neutrophil counts. A total of 12% and 20.8% of patients reported moderate/severe anxiety and depression, respectively, while only 53.7% of physicians had concerns about their patients' mental health. During the coronavirus disease 2019 (COVID-19) pandemic, 69.2% of patients reported a reduction in their income. Among these patients, 61.8% maintained their current treatment, while 7.3% switched to cheaper alternatives or discontinued treatment, with over 80% of these patients belonging to the low-income group. CONCLUSIONS: Overcoming challenges in patient-physician communication and treatment access is key to improving disease management and quality of life, especially for patients with low income. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT05092048.

Synthesis of superconducting phase of La0.5Ce0.5H10at high pressures.

Clathrate hydrideFm3-m-LaH10has been proven as the most extraordinary superconductor with the critical temperatureTcabove 250 K upon compression of hundreds of GPa in recent years. A general hope is to reduce the stabilization pressure and maintain the highTcvalue of the specific phase in LaH10. However, strong structural instability distortsFm3-mstructure and leads to a rapid decrease ofTcat low pressures. Here, we investigate the phase stability and superconducting behaviors ofFm3-m-LaH10with enhanced chemical pre-compression through partly replacing La by Ce atoms from both experiments and calculations. For explicitly characterizing the synthesized hydride, we choose lanthanum-cerium alloy with stoichiometry composition of 1:1. X-ray diffraction and Raman scattering measurements reveal the stabilization ofFm3-m-La0.5Ce0.5H10in the pressure range of 140-160 GPa. Superconductivity withTcof 175 ± 2 K at 155 GPa is confirmed with the observation of the zero-resistivity state and supported by the theoretical calculations. These findings provide applicability in the future explorations for a large variety of hydrogen-rich hydrides.

18 months follow-up of deep molecular response 4.5 (MR4.5) with nilotinib in patients with newly diagnosed chronic-phase chronic myeloid leukemia: a prospective, multi-center study in China.

Introduction: Early stable deep molecular response (DMR) to nilotinib is associated with goal of treatment-free remission (TFR) in patients with chronic-phase chronic myeloid leukemia (CML-CP). It is important to early distinguish between patients who can achieve a DMR and those who are fit for TFR. Methods: We performed a multicenter study to explore the early cumulative MR4.5 rate at 18 months with nilotinib in patients with newly diagnosed CML-CP (ND-CML-CP) in China. Of the 29 institutes, 106 patients with ND-CML-CP received nilotinib (300 mg BID). Results and discussion: The cumulative MR4.5 rate of nilotinib treatment at 18 months was 69.8% (74/106). The cumulative MMR and MR4.0 rates for nilotinib at 18 months were 94.3% (100/106) and 84.9% (90/106), respectively. Patients with an ultra-early molecular response (u-EMR) at 6 weeks were not significantly different in obtaining DMR or MMR by 24 months compared with those without u-EMR (p = 0.7584 and p = 0.9543, respectively). Our study demonstrated that nilotinib treatment in patients with ND-CML-CP contributed to obtain high early MR4.5.

Ice-confined synthesis of highly ionized 3D-quasilayered polyamide nanofiltration membranes.

Existing polyamide (PA) membrane synthesis protocols are underpinned by controlling diffusion-dominant liquid-phase reactions that yield subpar spatial architectures and ionization behavior. We report an ice-confined interfacial polymerization strategy to enable the effective kinetic control of the interfacial reaction and thermodynamic manipulation of the hexagonal polytype (Ih) ice phase containing monomers to rationally synthesize a three-dimensional quasilayered PA membrane for nanofiltration. Experiments and molecular simulations confirmed the underlying membrane formation mechanism. Our ice-confined PA nanofiltration membrane features high-density ionized structure and exceptional transport channels, realizing superior water permeance and excellent ion selectivity.

Superconductivity Above 100 K Predicted in Carbon-Cage Network.

To explore carbide superconductors with higher transition temperature, two novel carbon structures of cage-network are designed and their superconductivity is studied by doping metals. MC6 and MC10 are respectively identified as C24 and C32 cage-network structures. This study finds that both carbon structures drive strong electron-phonon interaction and can exhibit superconductivity above liquid nitrogen temperature. Importantly, the superconducting transition temperatures above 100 K are predicted to be achieved in C24 -cage-network systems doped by Na, Mg, Al, In, and Tl at ambient pressure, which is far higher than those in graphite, fullerene, and other carbides. Meanwhile, the superconductivity of cage-network carbides is also found to be sensitive to the electronegativity and concentration of dopant M. The result indicates that the higher transition temperatures can be obtained by optimizing the carbon-cage-network structures and the doping conditions. The study suggests that the carbon-cage-network structure is a direction to explore high-temperature superconducting carbides.

Proton-controlled molecular ionic ferroelectrics.

Molecular ferroelectric materials consist of organic and inorganic ions held together by hydrogen bonds, electrostatic forces, and van der Waals interactions. However, ionically tailored multifunctionality in molecular ferroelectrics has been a missing component despite of their peculiar stimuli-responsive structure and building blocks. Here we report molecular ionic ferroelectrics exhibiting the coexistence of room-temperature ionic conductivity (6.1 × 10-5 S/cm) and ferroelectricity, which triggers the ionic-coupled ferroelectric properties. Such ionic ferroelectrics with the absorbed water molecules further present the controlled tunability in polarization from 0.68 to 1.39 µC/cm2, thermal conductivity by 13% and electrical resistivity by 86% due to the proton transfer in an ionic lattice under external stimuli. These findings enlighten the development of molecular ionic ferroelectrics towards multifunctionality.

Experimental simulation of symmetry-protected higher-order exceptional points with single photons.

Exceptional points (EPs) of non-Hermitian (NH) systems have recently attracted increasing attention due to their rich phenomenology and intriguing applications. Compared to the predominantly studied second-order EPs, higher-order EPs have been assumed to play a much less prominent role because they generically require the tuning of more parameters. Here, we experimentally simulate two-dimensional topological NH band structures using single-photon interferometry, and observe topologically stable third-order EPs obtained by tuning only two real parameters in the presence of symmetry. In particular, we explore how different symmetries stabilize qualitatively different third-order EPs: the parity-time symmetry leads to a generic cube-root dispersion, while a generalized chiral symmetry implies a square-root dispersion coexisting with a flat band. Additionally, we simulate fourfold degeneracies, composed of the non-defective twofold degeneracies and second-order EPs. Our work reveals the abundant and conceptually richer higher-order EPs protected by symmetries and offers a versatile platform for further research on topological NH systems.

Carbon Capture Membranes Based on Amorphous Polyether Nanofilms Enabled by Thickness Confinement and Interfacial Engineering.

Thin-film composite membranes are a leading technology for post-combustion carbon capture, and the key challenge is to fabricate defect-free selective nanofilms as thin as possible (100 nm or below) with superior CO2/N2 separation performance. Herein, we developed high-performance membranes based on an unusual choice of semi-crystalline blends of amorphous poly(ethylene oxide) (aPEO) and 18-crown-6 (C6) using two nanoengineering strategies. First, the crystallinity of the nanofilms decreases with decreasing thickness and completely disappears at 500 nm or below because of the thickness confinement. Second, polydimethylsiloxane is chosen as the gutter layer between the porous support and selective layer, and its surface is modified with bio-adhesive polydopamine (<10 nm) with an affinity toward aPEO, enabling the formation of the thin, defect-free, amorphous aPEO/C6 layer. For example, a 110 nm film containing 40 mass % C6 in aPEO exhibits CO2 permeability of 900 Barrer (much higher than a thick film with 420 Barrer), rendering a membrane with a CO2 permeance of 2200 GPU and CO2/N2 selectivity of 27 at 35 °C, surpassing Robeson's upper bound. This work shows that engineering at the nanoscale plays an important role in designing high-performance membranes for practical separations.

Evaluation of physician guideline adherence and areas for improvement in managing patients with chronic myeloid leukemia: a cross-sectional survey.

The experience of a physician at a clinical center is among the critical factors in managing chronic myeloid leukemia (CML) during its treatment with tyrosine kinase inhibitors (TKIs). The authors conducted a cross-sectional questionnaire to investigate barriers to physician use of published evidence-based guidelines in CML management in a real-world setting. Among the participating physicians (N = 407), 99.8% of physicians reported that CML guidelines were useful; however, only 62.9% of physicians reported that they follow guidelines in real-time. Although 90.7% of physicians prefer second-generation TKIs as the first-line treatment, imatinib (88.2%) remains the most widely administered TKI in the first-line setting. Only 50.6% of physicians switched the treatment when patients failed to achieve early molecular response (at 3 months), whereas 70.3% of physicians switched the treatment when patients' response to TKI was inadequate at 6 months and/or 12 months. Moreover, only 43.5% of physicians considered treatment-free remission (TFR) as one of the top 3 goals for their patients. The major concern to obtain TFR was patients' adherence. This study demonstrated that CML management was generally in line with the current guidelines, but some of the details at the point of care are needed to be improved in CML.

Routing the Exciton Emissions of WS2 Monolayer with the High-Order Plasmon Modes of Ag Nanorods.

Locally routing the exciton emissions in two-dimensional (2D) transition-metal dichalcogenides along different directions at the nanophotonic interface is of great interest in exploiting the promising 2D excitonic systems for functional nano-optical components. However, such control has remained elusive. Herein we report on a facile plasmonic approach for electrically controlled spatial modulation of the exciton emissions in a WS2 monolayer. The emission routing is enabled by the resonance coupling between the WS2 excitons and the multipole plasmon modes in individual silver nanorods placed on a WS2 monolayer. Different from prior demonstrations, the routing effect can be modulated by the doping level of the WS2 monolayer, enabling electrical control. Our work takes advantage of the high-quality plasmon modes supported by simple rod-shaped metal nanocrystals for the angularly resolved manipulation of 2D exciton emissions. Active control is achieved, which offers great opportunities for the development of nanoscale light sources and nanophotonic devices.

Palladium-Percolated Networks Enabled by Low Loadings of Branched Nanorods for Enhanced H2 Separations.

Nanoparticles (NPs) at high loadings are often used in mixed matrix membranes (MMMs) to improve gas separation properties, but they can lead to defects and poor processability that impede membrane fabrication. Herein, it is demonstrated that branched nanorods (NRs) with controlled aspect ratios can significantly reduce the required loading to achieve superior gas separation properties while maintaining excellent processability, as demonstrated by the dispersion of palladium (Pd) NRs in polybenzimidazole for H2 /CO2 separation. Increasing the aspect ratio from 1 for NPs to 40 for NRs decreases the percolation threshold volume fraction by a factor of 30, from 0.35 to 0.011. An MMM with percolated networks formed by Pd NRs at a volume fraction of 0.039 exhibits H2 permeability of 110 Barrer and H2 /CO2 selectivity of 31 when challenged with simulated syngas at 200 °C, surpassing Robeson's upper bound. This work highlights the advantage of NRs over NPs and nanowires and shows that right-sizing nanofillers in MMMs is critical to construct highly sieving pathways at minimal loadings. This work paves the way for this general feature to be applied across materials systems for a variety of chemical separations.

Bifunctional Gas Diffusion Electrode Enables In Situ Separation and Conversion of CO2 to Ethylene from Dilute Stream.

The requirement of concentrated carbon dioxide (CO2 ) feedstock significantly limits the economic feasibility of electrochemical CO2 reduction (eCO2 R) which often involves multiple intermediate processes, including CO2 capture, energy-intensive regeneration, compression, and transportation. Herein, a bifunctional gas diffusion electrode (BGDE) for separation and eCO2 R from a low-concentration CO2 stream is reported. The BGDE is demonstrated for the selective production of ethylene (C2 H4 ) by combining high-density-polyethylene-derived porous carbon (HPC) as a physisorbent with polycrystalline copper as a conversion catalyst. The BGDE shows substantial tolerance to 10 vol% CO2 exhibiting a Faradaic efficiency of ≈45% toward C2 H4 at a current density of 80 mA cm-2 , outperforming previous reports that utilized such partial pressure (PCO2 = 0.1 atm and above) and unaltered polycrystalline copper. Molecular dynamics simulation and mixed gas permeability assessment reveal that such selective performance is ensured by high CO2 uptake of the microporous HPC as well as continuous desorption owing to the molecular diffusion and concentration gradient created by the binary flow of CO2 and nitrogen (CO2 |N2 ) within the sorbent boundary. Based on detailed techno-economic analysis, it is concluded that this in situ process can be economically compelling by precluding the C2 H4 production cost associated with the energy-intensive intermediate steps of the conventional decoupled process.

Moiré magnetic exchange interactions in twisted magnets.

In addition to moiré superlattices, twisting can also generate moiré magnetic exchange interactions (MMEIs) in van der Waals magnets. However, owing to the extreme complexity and twist-angle-dependent sensitivity, all existing models fail to fully capture MMEIs and thus cannot provide an understanding of MMEI-induced physics. Here, we develop a microscopic moiré spin Hamiltonian that enables the effective description of MMEIs via a sliding-mapping approach in twisted magnets, as demonstrated in twisted bilayer CrI3. We show that the emergence of MMEIs can create a magnetic skyrmion bubble with non-conserved helicity, a 'moiré-type skyrmion bubble'. This represents a unique spin texture solely generated by MMEIs and ready to be detected under the current experimental conditions. Importantly, the size and population of skyrmion bubbles can be finely controlled by twist angle, a key step for skyrmion-based information storage. Furthermore, we reveal that MMEIs can be effectively manipulated by substrate-induced interfacial Dzyaloshinskii-Moriya interactions, modulating the twist-angle-dependent magnetic phase diagram, which solves outstanding disagreements between theories and experiments.

Dimensional Transformation of Molecular Magnetic Materials.

Two-dimensional (2D) magnetic layered materials have revolutionized size dependent magnetism to manipulate spin-based devices. However, it has been challenging to artificially create 2D magnetic materials from three-dimensional (3D) crystal structures with a variety of material groups. Here, we present the dimensionality manipulation via cation exchange of a 3D Prussian blue analogue [RbMnFe(CN)6] toward a 2D magnetic sheet [(K,Rb)(V,Mn)(Cr,Fe)(CN)6] with the magnetic ordering temperature rising from 12 to 330 K. Such a 2D magnetic sheet achieves crystalline V-Cr coordination in the Prussian blue lattice with pronounced anisotropy and stimuli responsiveness. The pressure dependent magnetic tunability of such 2D networks is predicted using first-principles calculations and demonstrated using the phase transitions of the hydrogel. This previously unobserved phenomenon of dimensional manipulation of a bulk crystal structure provides a rational strategy to expand the diversity and chemical compositions of 2D molecular magnetic material libraries.