bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Self‐Assembly Enables Tuning of Nanopores in Atomically Thin Graphene Membranes for Highly Selective Transport
Authors: Jang Doojoon , Bakli Chirodeep , Chakraborty Suman , Karnik Rohit 
Published: January 2022

AbstractAtomically thin membranes comprising nanopores in a 2D material promise to surpass the performance of polymeric membranes in several critical applications, including water purification, chemical and gas separations, and energy harvesting. However, fabrication of membranes with precise pore size distributions that provide exceptionally high selectivity and permeance in a scalable framework remains an outstanding challenge. Circumventing these constraints, here, a platform technology is developed that harnesses the ability of oppositely charged polyelectrolytes to self‐assemble preferentially across larger, relatively leaky atomically thin nanopores by exploiting the lower steric hindrance of such larger pores to molecular interactions across the pores. By selectively tightening the pore size distribution in this manner, self‐assembly of oppositely charged polyelectrolytes simultaneously introduced on opposite sides of nanoporous graphene membranes is demonstrated to discriminate between nanopores to seal non‐selective transport channels, while minimally compromising smaller, water‐selective pores, thereby remarkably attenuating solute leakage. This improved membrane selectivity enables desalination across centimeter‐scale nanoporous graphene with 99.7% and >90% rejection of MgSO4 and NaCl, respectively, under forward osmosis. These findings provide a versatile strategy to augment the performance of nanoporous atomically thin membranes and present intriguing possibilities of controlling reactions across 2D materials via exclusive exploitation of pore size‐dependent intermolecular interactions.
Pseudocapacitive Conjugated Polyelectrolyte/2D Electrolyte Hydrogels with Enhanced Physico‐Electrochemical Properties
Authors: Quek Glenn , Su Yude , Donato Ricardo K. , Vázquez Ricardo J. , Marangoni Valeria S. , Ng Pei Rou , Costa Mariana C. F. , Kundukad Binu , Novoselov Konstantin S. , Neto Antonio H. Castro , Bazan Guillermo C. 
Published: January 2022

AbstractConducting polymer hydrogels (CPHs) are an attractive class of materials that synergize the electrical properties of organic semiconductors with the physical properties of hydrogels. Of particular interest is the implementation of CPHs as electrode materials for electrochemical energy storage by taking advantage of redox‐tunable conjugated backbones and the large electroactive surface area. Herein, the use of 2D electrolytes as an effective post‐polymerization additive to enhance the pseudocapacitive performance of CPHs, is demonstrated. By using the self‐doped conjugated polyelectrolyte CPE‐K hydrogel as a model system, improvements in cycling stability, specific capacitance and working voltage window upon addition of the 2D electrolytes, are shown. Furthermore, positively charged 2D electrolytes to be more effective than their negatively charged counterparts are revealed. Rheology measurements and SEM imaging indicate that the 2D electrolytes serve as non‐covalent cross‐linkers that help in forming a mechanically more robust and highly percolated conducting network. These results provide a new and simple to execute post‐polymerization strategy to optimize the electrochemical performance of CPH‐based pseudocapacitors.
Electronic Transport in 2D‐Based Printed FETs from a Multiscale Perspective
Authors: Perucchini Marta , Marian Damiano , Marin Enrique G. , Cusati Teresa , Iannaccone Giuseppe , Fiori Gianluca 
Published: January 2022

AbstractAs 2D materials (2DMs) gain the research limelight as a technological option for obtaining on‐demand printed low‐cost integrated circuits with reduced environmental impact, theoretical methods able to provide the necessary fabrication guidelines acquire fundamental importance. Here, a multiscale modeling technique is exploited to study electronic transport in devices consisting of a printed 2DM network of flakes. The approach implements a Monte Carlo scheme to generate the flake distribution. By means of ab initio density functional theory calculations together with non equilibrium Green's functions formalism, detailed physical insights on flake‐to‐flake transport mechanisms are provided. This later feeds a 3D drift‐diffusion and Poisson solution to compute self‐consistently transport and electrostatics in the device. The method is applied to MoS2and graphene‐based dielectrically gated FETs, highlighting the impact of the structure density and variability on the mobility and sheet resistance. The prediction capability of the proposed approach is validated against electrical measurements of in‐house printed graphene conductive lines as a function of film thickness, demonstrating its strong potential as a guide for future experimental activity in the field.
Very High Density (>1014 cm−2) Polarization‐Induced 2D Hole Gases Observed in Undoped Pseudomorphic InGaN/AlN Heterostructures
Authors: Chaudhuri Reet , Zhang Zexuan , Xing Huili Grace , Jena Debdeep 
Published: January 2022

AbstractHigh hole densities are desired in p‐channel field effect transistors to improve the speed and on‐currents. Building on the recently discovered undoped, polarization‐induced GaN/AlN 2D hole gas (2DHG), this work demonstrates the tuning of the piezoelectric polarization difference across the heterointerface by introducing indium in the GaN channel. Using careful design and epitaxial growths, these pseudomorphic (In)GaN/AlN heterostructures result in some of the highest carrier densities of >1014 cm−2 in a III‐nitride heterostructure—just an order below the intrinsic crystal limit of ≈1015 cm−2. These ultra‐high density InGaN/AlN 2DHGs show room temperature mobilities of 0.5–4 cm2 V−1 s−1 and do not freeze out at low temperatures. A characteristic alloy fluctuation energy of 1.0 eV for hole scattering in InGaN alloy is proposed based on the experiments.
A Strain‐Relaxation Red Phosphorus Freestanding Anode for Non‐Aqueous Potassium Ion Batteries
Authors: Feng Wencong , Wang Hong , Jiang Yalong , Zhang Huazhang , Luo Wen , Chen Wei , Shen Chunli , Wang Chenxu , Wu Jinsong , Mai Liqiang 
Published: January 2022

AbstractRed phosphorus (RP), as a promising anode for potassium‐ion batteries (KIBs), and has attracted extensive attention due to its high theoretical capacity, low redox potential, and abundant natural sources. However, RP shows dramatic capacity decay and rapid structure degradation caused by huge volume expansion and poor electronic conductivity. Here, a volume strain‐relaxation electrode structure is reported, by encapsulating well‐confined amorphous RP in 3D interconnected sulfur, nitrogen co‐doped carbon nanofibers (denoted as RP@S‐N‐CNFs). In situ transmission electron microscopy and the corresponding chemo‐mechanical simulation reveal the excellent structural integrity and robustness of the N, S carbon matrix. As a freestanding anode for KIBs, the RP@S‐N‐CNFs electrode exhibits high reversible capacities (566.7 mAh g−1 after 100 cycles at 0.1 A g−1) and extraordinary durability (282 mAh g−1 after 2000 cycles at 2 A g−1). The highly reversible one‐electron transfer mechanism with a final discharge product of KP and faster kinetics are demonstrated through in situ characterizations and density functional theory calculations. This work sheds light on the rational design of large‐volume‐vibration type anodes for next‐generation high‐performance KIBs.
Multiscale modeling of ion transport in porous electrodes
Authors: Tao Haolan , Chen Gong , Lian Cheng , Liu Honglai , Coppens Marc‐Olivier 
Published: January 2022

AbstractIon transport through nanoporous materials is of fundamental importance for the design and development of filtration membranes, electrocatalysts, and electrochemical devices. Recent experiments have shown that ion transport across porous materials is substantially different from that in individual pores. Here, we report a new theoretical framework for ion transport in porous materials by combining molecular dynamics (MD) simulations at nanopore levels with the effective medium approximation to include pore network properties. The ion transport is enhanced with the combination of strong confinement and dominating surface properties at the nanoscale. We find that the overlap of electric double layers and ion–water interaction have significant effects on the ionic distribution, flux, and conductance of electrolytes. We further evaluate the gap between individual nanopores and complex pore networks, focusing on pore size distribution and pore connectivity. This article highlights unique mechanisms of ion transport in porous materials important for practical applications.
Interventions for caregivers of older adults with dementia living in the community: A rapid review
Authors: Huggins Madison L 
Published: January 2022

AbstractBackgroundThis rapid review examined the literature regarding interventions, including volunteer navigation, that have been implemented to address the needs of caregivers of older adults with dementia living in the community. It is essential to understand the efficacy of interventions in meeting the needs of family and friend caregivers to ensure that the development of new interventions is evidence‐based, and will contribute to positive impacts for caregivers.MethodMEDLINE, CINHAL and EMBASE databases were searched. There is a robust body of empirical literature addressing the needs of caregivers, therefore, the rapid review focused on evidence from systematic reviews. Research question: “What is the empirical evidence on interventions (including navigation) to meet the needs of family caregivers of persons living with dementia?”. 19 systematic reviews were included for review.Result1) Psychosocial, psychoeducational, social support and multicomponent interventions consistently had positive impacts on a variety of outcomes. 2) Multicomponent interventions that are tailored to the needs of individual caregivers are the most effective interventions and should be utilized in future program development. 3) The most effective combination of interventions that should be incorporated into multicomponent interventions is unknown and should be investigated further.ConclusionPsychoeducational, psychosocial, social support, and multicomponent interventions consistently result in positive impacts on a variety of outcomes. However, the most impactful combination of specific interventions that should be utilized in multicomponent interventions is unclear. Despite this uncertainty, the repeated success of psychoeducational, psychosocial and social support interventions suggests that these components should be utilized in conjunction with one another in multicomponent interventions that are tailored to the needs of individuals. In order to accomplish this, future programs need to provide adequate time for caregivers and intervention administrators to develop meaningful relationships in which the caregiver feels comfortable to share their individual needs, and the administrator can truly understand them. Nav‐CARE may serve as a program that can incorporate psychosocial, psychoeducational and social support aspects of interventions resulting in positive impacts on caregivers. Improved programs that meet the needs of caregivers will adequately support caregivers, PWD and reduce financial costs to our healthcare system.
Reversible Selbstorganisation eines N‐heterocyclischen Carbens auf Metalloberflächen
Authors: Ren Jindong , Freitag Matthias , Gao Yuxiang , Bellotti Peter , Das Mowpriya , Schulze Lammers Bertram , Mönig Harry , Zhang Yuyang , Daniliuc Constantin G. , Du Shixuan , Fuchs Harald , Glorius Frank 
Published: January 2022

AbstractCyclohexyl(alkyl)(amino)carbene (cyCAAC) bilden selbstorganisierende Monolagen, die durch den Ring‐Flip der Cyclohexyl‐Seitengruppe reversibel von einer dicht gepackten Trimer‐Phase in eine kettenartige Dimer‐Phase umgeschaltet werden können. Mehrere Methoden, darunter Rastertunnelmikroskopie (STM), Röntgen‐Photoelektronenspektroskopie (XPS) und Dichtefunktionaltheorie (DFT)‐Berechnungen, identifizierten ein eindeutiges Isomer (axiales oder äquatoriales Sesselkonformer) in jeder Phase und stützen somit die Schlussfolgerung hinsichtlich des Einflusses der molekularen Oberflächengeometrie auf die Selbstorganisation von cyCAAC. Darüber hinaus wurden verschiedene Substrate wie Ag(111) und Cu(111) getestet, um die Bedeutung der Wechselwirkungen zwischen cyCAAC und der Oberfläche für die auf cyCAAC basierenden Nanomuster aufzuklären. Die Untersuchungen von gemusterten Oberflächen führten zu einem tieferen Verständnis der cyCAAC‐Bindungsweise, der Oberflächengeometrie und der reversiblen Selbstorganisation, die in den Bereichen Katalyse, Biosensor‐Design und Oberflächenfunktionalisierung von herausragender Bedeutung sind.
Seitenspezifische Funktionalisierung von Janusfasern aus rekombinanter Spinnenseide
Authors: Lang Gregor , Grill Carolin , Scheibel Thomas 
Published: January 2022

AbstractMittels moderner Biotechnologie können heutzutage neue Materialien mit maßgeschneiderten Eigenschaften entwickelt werden. Ziel dieser Studie war es, funktionalisierbare Janusfasern aus rekombinanten Spinnenseidenproteinen herzustellen. Dabei wurde zunächst das Cystein‐modifizierte Seidenkonstrukt ntagCyseADF4(κ16) nassgesponnen. Auf den Fasern wurden anschließend mittels Thiol‐En‐Klickchemie Goldnanopartikel (AuNPs) gekuppelt. Als Indikator für eine hohe AuNP‐Beladungsdichte wurde ein deutlich reduzierter spezifischer elektrischer Widerstand der Fasern gemessen. Anschließend wurden mittels Elektrospinnen zweiseitige Janusfasern mit “nicht‐funktionalem” eADF4(C16) auf der einen und “funktionalem” ntagCyseADF4(κ16) auf der anderen Seite hergestellt. Eine Nachbehandlung wurde etabliert, um die Seidenfasern in Wasser unlöslich zu machen. Es wurde gezeigt, dass die AuNP‐Kupplung ausschließlich auf der ntagCyseADF4(κ16)‐Seite auftrat. Die hochselektive Funktionalisierung zeigt das Potenzial solcher seidenbasierten Systeme zur Realisierung komplexer bifunktioneller Strukturen mit räumlicher Auflösung im Nanobereich.
Master of Chaos and Order: Opposite Microstructures of PCL‐co‐PGA‐co‐PLA Accessible by a Single Catalyst**
Authors: Rittinghaus Ruth D. , Zenner Johannes , Pich Andrij , Kol Moshe , Herres‐Pawlis Sonja 
Published: January 2022

AbstractOne catalyst, two reaction set‐ups, three monomers and unlimited macromolecular microstructural designs: The iron guanidine complex [FeCl2(TMG5NMe2asme)] (1) polymerizes lactide faster than the industrially used Sn(Oct)2 and shows high activity towards glycolide and ϵ‐caprolactone. Its distinguished features enable the synthesis of both block and random‐like copolymers in the melt by a simple change of the polymerization set‐up. Sequential addition of monomers yields highly ordered block copolymers including the symmetrical PLA‐b‐PGA‐b‐PCL‐b‐PGA‐b‐PLA pentablock copolymers, while polymerizations of monomer mixtures feature enhanced transesterifications and pave the way to di‐ and terpolymers with highly dispersed repeating unit distributions. A robust catalyst active under industrially applicable conditions and producing copolymers with desired microstructures is a major step towards biocompatible polymers with tailor‐made properties as alternatives for traditional plastics on the way towards a sustainable, circular material flow.
Reversible Self‐Assembly of an N‐Heterocyclic Carbene on Metal Surfaces
Authors: Ren Jindong , Freitag Matthias , Gao Yuxiang , Bellotti Peter , Das Mowpriya , Schulze Lammers Bertram , Mönig Harry , Zhang Yuyang , Daniliuc Constantin G. , Du Shixuan , Fuchs Harald , Glorius Frank 
Published: January 2022

AbstractSelf‐assembly of cyclohexyl cyclic (alkyl)(amino)carbenes (cyCAAC) can be realized and reversibly switched from a close‐packed trimer phase to a chainlike dimer phase, enabled by the ring‐flip of the cyclohexyl wingtip. Multiple methods including scanning tunneling microscopy (STM), X‐ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations identified a distinct isomer (axial or equatorial chair conformer) in each phase, and consequently support the conclusion regarding the determination of molecular surface geometry on the self‐assembly of cyCAAC. Moreover, various substrates such as Ag (111) and Cu (111) are tested to elucidate the importance of cyCAAC‐surface interactions on cyCAAC based nanopatterns. These investigations of patterned surfaces prompted a deep understanding of cyCAAC binding mode, surface geometry and reversible self‐assembly, which are of paramount significance in the areas of catalysis, biosensor design and surface functionalization.
High‐Performance Sulfate Optical Materials Exhibiting Giant Second Harmonic Generation and Large Birefringence
Authors: Dong Xuehua , Huang Ling , Zeng Hongmei , Lin Zhien , Ok Kang Min , Zou Guohong 
Published: January 2022

AbstractDiscovering novel sulfate optical materials with strong second‐harmonic generation (SHG) and large birefringence is confronted by a great challenge attributed to the intrinsically weak polarizability and optical anisotropy of tetrahedral SO4 groups. Herein, two superior‐performing sulfate optical materials, namely, noncentrosymmetric Hg3O2SO4 and centrosymmetric CsHgClSO4 ⋅ H2O, have been successfully synthesized through the introduction of a highly polarizable d10 metal cation, Hg2+. The unique component layers in the reported compounds, [Hg3O2SO4]∞ layers in Hg3O2SO4 and [HgClSO4(H2O)]
layers in CsHgClSO4 ⋅ H2O, induce enlarged birefringence in each sulfate. Remarkably, Hg3O2SO4 exhibits a very large SHG response (14 times that of KH2PO4), which is the strongest efficiency among all the reported nonlinear optical sulfates. Detailed theoretical calculations confirm that the employment of highly polarizable Hg2+ is an effective strategy to design superior optical materials with large birefringence and strong SHG response.
Enhancing mechanical performance and wet‐skid resistance of emulsion styrene butadiene rubber/natural rubber latex composites via in‐situ hybridization of silanized graphene oxide and silica
Authors: Li Qiao , Lin Guangyi , Chen Shouzhen , Zhang Lin , Song Yingjie , Geng Chuanbao , Qu Siyuan , Jing Yuan , Liu Fumin , Liang Zhenning 
Published: January 2022

AbstractThe wet skid resistance and thermal conductivity of “green tire” are the focus of research. In this work, through the use of different types of silane coupling agents, the surface of SiO2 and graphene oxide (GO) were grafted with amino and epoxy groups, respectively. The in‐situ generated SiO2 was grafted to the surface of GO by ring‐opening reaction of amino and epoxy groups. The emulsion styrene butadiene rubber/natural rubber latex (ESBR/NRL) composites were prepared by gas assisted spray flocculation process to improve the dispersion performance of hybrid filler. Because the surface of the hybrid filler contains amino and epoxy groups, it can be added as a reactive compatibilizer into the ESBR/NRL composites to improve the interface compatibility and synergistic reinforcement effect. Compared with the composites filled with SiO2, the composites filled with hybrid filler have excellent wet skid resistance and mechanical properties. When the mass ratio of GO to SiO2 is 3:10, the mechanical properties and wet skid resistance of rubber composites increase by 96.7% and 20.6%, respectively. Our preparation method of hybrid filler and flocculation process of rubber composites have broad application prospects in “green tire.”
A novel material based on deep eutectic solvents and its application in in‐situ modified silica‐reinforced styrene‐butadiene rubber
Authors: Wei Liping , Shen Mei , Xin Zhenxiang 
Published: January 2022

AbstractIn the tread compound of Green tire, silica dispersity is critical for obtaining high‐performance rubber composites. Ionic liquids have been successfully applied in improving the dispersity of silica through chemical and physical interaction. However, recent research has found that ionic liquids are harmful to the ecological environment. Meanwhile, the price of them is high. In this paper, the deep eutectic solvents (DESs‐Choline Chloride: urea) was synthesized successfully. Then it was directly introduced to prepare silica‐filled styrene‐butadiene rubber (SBR) compound via an in‐situ method. The carbonyl group and amino in DESs could constitute a hydrogen bond with the silanol on the silica surface. The hydroxyl groups were able to react with the silanol groups. The amino groups in DESs could treat as a secondary facilitator, which accelerated the curing rate. The results showed that DESs improved the dispersity of silica effectively and strengthened the interaction between silica and SBR chains. Particularly, the comprehensive performance of the rubber vulcanizates improved with an optimal ratio of bis(3‐triethoxysilypropyl)‐tetrasulfide (TESPT) to DESs being of 1:1. In addition, the DESs will serve as a novel material in silica‐filled SBR composites, which will expand its application in the tire industry.
Finite‐time control of spacecraft and hardware in the loop tuning
Authors: Hajnorouzali Yasaman , Malekzadeh Maryam , Ataei Mohammad 
Published: January 2022

AbstractA nonlinear disturbance observer based on a super twisting controller is designed and implemented on the uncertain spacecraft attitude control subsystem simulator. The reaction wheels' angular momentum and their rate saturation are concerned in the controller design. The super twisting algorithm (STA) is devised in a way to make the reaction wheels into rest at the end of the maneuver. A nonlinear‐disturbance‐observer (NDO) is applied in estimating the external disturbances, unmodeled inertia moment, the eccentricity of rotation and mass center of simulator, and the reaction wheel saturation constraint. The finite‐time stability of the closed‐loop system is established according to the Lyapunov theory. The simulation and experimental results of this newly designed controller‐observer on the spacecraft attitude simulator are compared in uncertain conditions.
Improving Structural Stability and Anticoagulant Activity of a Thrombin Binding Aptamer by Aromatic Modifications
Authors: Busschaert Nathalie , Maity Debabrata , Samanta Pralok K. , English Niall J. , Hamilton Andrew D. 
Published: January 2022

AbstractThe thrombin binding aptamer (TBA) is a 15‐mer DNA oligonucleotide (5′‐GGT TGG TGT GGT TGG‐3′), that can form a stable intramolecular antiparallel chair‐like G‐quadruplex structure. This aptamer shows anticoagulant properties by interacting with one of the two anion binding sites of thrombin, namely the fibrinogen‐recognition exosite. Here, we demonstrate that terminal modification of TBA with aromatic fragments such as coumarin, pyrene and perylene diimide (PDI), improves the G‐quadruplex stability. The large aromatic surface of these dyes can π‐π stack to the G‐quadruplex or to each other, thereby stabilizing the aptamer. With respect to the original TBA, monoPDI‐functionalized TBA exhibited the most remarkable improvement in melting temperature (ΔTm≈+18 °C) and displayed enhanced anticoagulant activity.