bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exceptional Alignment in a Donor–Acceptor Conjugated Polymer via a Previously Unobserved Liquid Crystal Mesophase
Authors: Schrickx Harry M. , Kashani Somayeh , Buck Lauren , Ding Kan , Rech Jeromy J. , Flagg Lucas Q. , Li Ruipeng , Kudenov Michael W. , You Wei , Richter Lee J. , Ade Harald , O'Connor Brendan T. 
Published: April 2024

AbstractOrienting polymer semiconductors is desirable to optimize device characteristics, provide insight into microstructure, and magnify subtle phase behavior. Here, a combination of uniaxial strain and subsequent heating of the donor–acceptor (DA) polymer PBnDT‐FTAZ is discovered to lead to exceptional optical dichroic ratios of up to 38 (and close to 50 near the polymer's absorption edge). This alignment is achieved due to the existence of a previously undetected thermotropic liquid crystal (LC) mesophase. The LC transition, not discernable through calorimetry, is uncovered through a combination of in situ UV–vis spectroscopy, X‐ray scattering, and dynamic mechanical analysis (DMA). Comparing PBnDT‐FTAZ to the non‐fluorinated PBnDT‐HTAZ and the homo polymer PBnDT, all of which show similar thermal transitions, reveals that exceptional alignment is only found in PBnDT‐FTAZ. This is attributed to the PBnDT‐FTAZ film having two distinct liquid crystal populations, and the polymer templating to a highly aligned, high‐clearing temperature population when heated. The DMA thermal relaxation behavior observed here is also seen in other DA conjugated polymers suggesting that such thermotropic LC mesophases may be common in these materials. These findings demonstrate a polymer semiconductor with remarkable alignment and uncover phase behavior with broad implications for process‐structure‐property relationships in polymer semiconductors.
Visualizing Structure, Growth, and Dynamics of Li Dendrite in Batteries: From Atomic to Device Scales
Authors: Li Yonghe , Xu Hui , Ning Qiaoru , Li Shiting , Wang Jing , Wang Jiexin , Hu Zhongting , Tian Jinshu , Li Xiaonian , Han Yu , Zhu Yihan 
Published: April 2024

AbstractThe growth of lithium (Li) dendrites, characterized by construction of internal Li substrate and surface solid electrolyte interphase (SEI), represents a significant hurdle for both liquid‐state and solid‐state Li batteries. To better understand the growth behaviors of these dendrites at atomic to device scale, advanced electron microscopy techniques have emerged as a valuable tool, providing high temporal and spatial resolutions for real‐time observations. In this review, the mechanistic aspects of growth of Li dendrites are delved first from both thermodynamic and kinetic perspectives. Then, a systematic overview of the state‐of‐the‐art in‐situ devices is provided that is developed for integration into electron microscopes, detailing the corresponding static and dynamic structures of Li dendrites. Additionally, the utilization of the non‐destructive cryogenic TEM technique is explored to classify and compare the local fine structure information of as‐formed Li deposits, which are influenced by various factors such as current density, temperature, electrolyte composition, solvents, and additives. Overall, this review article offers a comprehensive understanding of the physical origins associated with Li dendrites, spanning from atomic to device scales and encompassing both liquid and all‐solid‐state battery scenarios, then envisioning fundamental principles and strategies for optimizing batteries and overcoming the critical challenges posed by Li dendrites.
Evolutionary Games‐Assisted Synchronization Metasurface for Simultaneous Multisource Invisibility Cloaking
Authors: Huang Min , Zheng Bin , Li Ruichen , Shen Lian , Li Xiaofeng , Lu Huan , Zhu Rongrong , Cai Tong , Chen Hongsheng 
Published: April 2024

AbstractThe realization of a metasurface cloak for the simultaneous invisibility of multiple sources presents a long‐standing scientific challenge. Ideally, for the establishment of a simultaneous multisource invisibility cloak, the metasurface must provide a wide phase coverage and angular stability in a single architecture, especially for broadband, wide‐angle, and even omnidirectional scenarios. However, achieving this goal has proven to be elusive thus far. Current approaches for implementing metasurface‐based invisibility cloak involve both active and passive metasurface. These approaches often rely on phase‐compensation mechanisms, which inevitably encounter issues related to limited incidence angles or narrow working bands. Here, a novel paradigm of synchronization metasurface optimized through an evolution‐optimization strategy, enabling the realization of simultaneous multisource invisibility cloaking, is proposed. The underlying physics of the synchronization metasurface relies on an evolution‐optimization strategy (an evolutionary game algorithm), which is used to get rid of the entanglement between incident directions, frequencies, and metasurface phase gradients. Consequently, the synchronization metasurface is capable of manipulating simultaneous incoming waves at any angle over a wide range (cloak). In experimental validation, the synchronization metasurface demonstrates an impressive capability to cloak both single and simultaneous double sources in any direction, highly resembling background fields.
A Superhuman Sensing Triboelectric Nanogenerator with Boosted Power Density and Durability via a Bio‐Inspired Janus Structure
Authors: Jin Chun , Zhang Chen , Yan Pengfei , Jiang Mengqi , Yin Rui , Li Kang , Zhao Weiwei , Bai Ziqian 
Published: April 2024

AbstractTriboelectric nanogenerators (TENG) not only enable sustainable self‐powered sensing of devices, but also have superhuman noncontact/contact identification capabilities, which are propelling humanity toward the intelligent era. However, the inherently low dielectric constant of triboelectric materials as well as the mechanical mismatch between electrodes and dielectric materials severely limited their efficient and stable output performance. Taking inspiration from the asymmetric structure and function of human skin, a novel single‐electrode TENG is developed, whose electrode and dielectric layer are integrated in a Janus architecture. By tuning the balance between gravity and the internal noncovalent interactions, gradient dispersion of carbon nanotubes in waterborne polyurethane networks can be feasibly achieved, which can boost the device performance by reinforcement in both the charge trapping capacity of the dielectric layer and the charge transfer of the electrode layer. As a proof‐of‐concept, triboelectric sensing and deep learning are integrated to realize the evolution from perception to identification under both noncontact (motion prediction) and contact (material identification) modes. The bionic design strategy of gradient Janus film can offer valuable insights into improving the output performance and durability of TENG. Additionally, the proximal prediction and tactile identification functions are also desirable attempts for future human‐machine interfaces.
Correlating Graphite Surface with Interphase for Fast‐Charging and Low‐Temperature Operation
Authors: Yin Yue , Peng Yu , Chen Jiawei , Wang Yonggang , Dong Xiaoli , Xia Yongyao 
Published: April 2024

AbstractThe properties of graphite surface can not only affect the interaction between graphite and electrolyte but also induce the formation of solid electrolyte interphase (SEI) film. Herein, the graphite surface is purposely treated to incorporate oxygen‐containing functional groups, which facilitates a desired Li2CO3‐rich SEI with high ionic conductivity and good mechanical stability. The modified graphite electrodes exhibit significant enhancement in electrochemical performance during rapid charging at the rate of 15 C, where an impressive capacity of 225 mAh g−1 is still maintained, corresponding to a capacity retention of 60.8%. Moreover, the modified electrodes showcase outstanding performance under wide temperature ranging from −50 to +65 °C, with an amazing capacity retention of 97.6% under −20 °C, the conceivable capacity of 105 mAh g−1 at −50 °C as well as excellent stability at both −20 °C and +65 °C. These findings offer valuable insights into the design of a thin and robust Li2CO3‐rich SEI layer via a facile chemical treatment of the graphite surface.
A Novel Coacervate Embolic Agent for Tumor Chemoembolization
Authors: Liu Menghui , Sun Yang , Zhou Yitong , Chen Yanlv , Yu Meng , Li Liujun , Yan Leye , Yuan Yajun , Chen Jiayao , Zhou Kaixiang , Shan Hong , Peng Xin 
Published: April 2024

AbstractTranscatheter arterial chemoembolization (TACE) has proven effective in blocking tumor‐supplied arteries and delivering localized chemotherapeutic treatment to combat tumors. However, traditional embolic TACE agents exhibit certain limitations, including insufficient chemotherapeutic drug‐loading and sustained‐release capabilities, non‐biodegradability, susceptibility to aggregation, and unstable mechanical properties. This study introduces a novel approach to address these shortcomings by utilizing a complex coacervate as a liquid embolic agent for tumor chemoembolization. By mixing oppositely charged quaternized chitosan (QCS) and gum arabic (GA), a QCS/GA polymer complex coacervate with shear‐thinning property is obtained. Furthermore, the incorporation of the contrast agent Iohexol (I) and the chemotherapeutic doxorubicin (DOX) into the coacervate leads to the development of an X‐ray‐opaque QCS/GA/I/DOX coacervate embolic agent capable of carrying drugs. This innovative formulation effectively embolizes the renal arteries without recanalization. More importantly, the QCS/GA/I/DOX coacervate can successfully embolize the supplying arteries of the VX2 tumors in rabbit ear and liver. Coacervates can locally release DOX to enhance its therapeutic effects, resulting in excellent antitumor efficacy. This coacervate embolic agent exhibits substantial potential for tumor chemoembolization due to its shear‐thinning performance, excellent drug‐loading and sustained‐release capabilities, good biocompatibility, thrombogenicity, biodegradability, safe and effective embolic performance, and user‐friendly application.
pH‐Triggered Transformable Peptide Nanocarriers Extend Drug Retention for Breast Cancer Combination Therapy
Authors: Yuan Xiaomeng , Liu Xiaoying , Li Hongjie , Peng Shan , Huang Haiqin , Yu Zhe , Chen Limei , Liu Xinlu , Bai Jingkun 
Published: April 2024

AbstractIncreasing the penetration and accumulation of antitumor drugs at the tumor site are crucial in chemotherapy. Smaller drug‐loaded nanoparticles (NPs) typically exhibit increased tumor penetration and more effective permeation through the nuclear membrane, whereas larger drug‐loaded NPs show extended retention at the tumor site. In addition, cancer stem cells (CSCs) have unlimited proliferative potential and are crucial for the onset, progression, and metastasis of cancer. Therefore, a drug‐loaded amphiphilic peptide, DDP‐ and ATRA‐loaded Pep1 (DA/Pep1), is designed that self‐assembles into spherical NPs upon the encapsulation of cis‐diamminedichloroplatinum (DDP) and all‐trans retinoic acid (ATRA). In an acidic environment, DA/Pep1 transforms into aggregates containing sheet‐like structures, which significantly increases drug accumulation at the tumor site, thereby increasing antitumor effects and inhibiting metastasis. Moreover, although DDP treatment can increase the number of CSCs present, ATRA can induce the differentiation of CSCs in breast cancer to increase the therapeutic effect of DDP. In conclusion, this peptide nanodelivery system that transforms in response to the acidic tumor microenvironment is an extremely promising nanoplatform that suggests a new idea for the combined treatment of tumors.
Flexible Electromagnetic Tactile Sensor Based on Double‐Layer High‐Density MEMS Coils and Tilted Magnetic Column Array
Authors: Liu Jianjun , Hou Xiaojuan , Liu Juan , Bi Xiaoxue , Wu Hui , Zhang Jie , Niu Lixin , Chen Wei , He Jian , Chou Xiujian 
Published: April 2024

AbstractWith the rapid development of wearable devices, tactile sensors have received extensive attention as supplements to vision and hearing. However, it remains challenging for a single tactile sensor to generate distinguishable electrical signals when receiving mechanical stimuli in different directions. Herein, a novel flexible electromagnetic tactile sensor (FETS) prepared by combining flexible double‐layer coils and a flexible tilted magnetic column array (TMCA) is presented. Flexible double‐layer high‐density coils are fabricated using the micro‐electromechanical system (MEMS) technology. The turns of the coil (1 × 1 cm) are 100, while both the line width and spacing of turns are 40 µm. TMCA is prepared using a template and magnetized along the axis direction. When a pulling force or pressure is applied to the TMCA, the magnetic flux decreases or increases correspondingly, allowing the FETS to accurately distinguish stimuli and produce different signals (−/+ or +/−). The FETS presents a sensitivity of up to 21.7 µV kPa−1 (0.05–10 kPa), a minimal magnetic field detection limit of 10 mT, a low‐pressure detection limit of 5 g, and good repeatability (5000 cycles). Additionally, the FETS is applied in robotic tactile testing, Morse code, and noncontact magnetic field recognition. It has potential applications in the Internet of Things (IoT) and information communication.
Reviews on Flexible Force Sensors Based on Fiber Assemblies with Mass Production Efficiency
Authors: Wu Liwei , Jin Yuting , Xia Zhaopeng , Han Jing , Han Wei , Dong Kai , Tang Youhong , Jiang Qian 
Published: April 2024

AbstractFlexible force sensors show great potential applications in smart wearable devices based on their softness and ease of deformation. Textiles are extremely compatible with the human body, where mechanical forces generated by human movements and physiological activities create rich application scenarios for flexible force sensors. Currently, the bottleneck in the development of flexible sensors depends on the breakthrough of mass production efficiency, which has been a research focus in recent years to accelerate the application of smart textiles in various fields. This work reviews the research progress of flexible force sensors based on fiber assemblies with mass production efficiency, which is discussed in four aspects: sensing mechanisms, structure design, preparation methods, and application. Finally, the challenges faced by mass production of flexible force sensors are analyzed and summarized, and a few inspirations for their future development direction are provided.
Programmable Meta‐Reflector for Multiple Tasks in Intelligent Connected Environments
Authors: Meftah Nawel , Ratni Badreddine , El Korso Mohammed Nabil , Burokur Shah Nawaz 
Published: April 2024

AbstractIn the face of the challenges posed by the advent of 5G, Internet of Things (IoT) and requirements of future communication generations, the urgent need for cutting‐edge technologies capable of adapting their operation to a variety of dynamic tasks for efficient signal propagation management is clear. Connected intelligent metasurfaces, distinguished by their ability to dynamically and autonomously adapt their responses, and able to interact with an external uncontrollable and fast‐changing communication environment to benefit from collective intelligence so as to determine the required action, are emerging as an innovative solution in this field. Herein, an intelligent connected system based on a programmable metasurface reflector, is presented and assessed in two scenarios simulating dynamic uplink and downlink communications. For the uplink configuration, the metasurface is exploited for the estimation of the direction of arrival (DOA) of an incoming wave, while for the downlink scenario, it enables the automated tracking of mobile targets using global positioning system (GPS) data updated from a real‐time database. Experimental results highlight the responsiveness of the metasurface and demonstrate efficiency in wave focusing and mobile target tracking.
The Emerging Heteroepitaxial NiSe2/Nb2C: A Two‐In‐One Bi‐Functional Material Architecture for Electrocatalytic and Supercapattery Application
Authors: Arunkumar Murugesan , Nasrin Kabeer , Allwyn Nadar , Kavinkumar Parthasarathy , Sivashanmugam Arumugam , Sathish Marappan 
Published: April 2024

AbstractThe rational design of electrode materials is pivotal for optimizing the performance of energy storage and conversion systems such as supercapattery and electrocatalysis. In this study, a one‐step supercritical fluid synthesis is presented to craft a unique heteroepitaxial composite, incorporating nickel di‐selenide nanoparticles on niobium carbide MXene nanosheets in various ratios. The integration of 2D nanosheets enhances the kinetics of the electrode reaction process, while NiSe2 facilitates efficient charge transport in MXene. The composite demonstrated superior performance with the 1:2 ratio of NiSe2/Nb2CTx demonstrates an impressive specific capacitance of 1309 C g−1 at 2 A g−1 current density in a three‐electrode system. Furthermore, the asymmetric supercapattery, featuring NiSe2/Nb2CTx 1:2 (positive electrode) and bio‐derived activated carbon (AC) (negative electrode) achieves a gravimetric capacitance of 205 C/g at 0.5 A g−1 current density, a power density of 10,800 W kg−1 at the energy density of 64 Wh kg−1, with 90% retention after 12 000 cycles. As a catalyst for water oxidation, the NiSe2/Nb2CTx 1:2 exhibits the lowest over potential of 359 mV at the current density 10 mA cm−2 and Tafel slope of 105 mV dec−1. This investigation introduces an innovative approach for developing high‐performance supercapattery electrode materials and electrocatalysts using MXene.
Hydrogel‐Reactive‐Microenvironment Powering Reconfiguration of Polymer Architectures
Authors: Liu Pengchao , Mao Zhengyi , Zhao Yan , Yin Jian'an , Chu Chengshengze , Chen Xuliang , Lu Jian 
Published: April 2024

AbstractReconfiguration of architected structures has great significance for achieving new topologies and functions of engineering materials. Existing reconfigurable strategies have been reported, including approaches based on heat, mechanical instability, swelling, origami/kirigami designs, and electromagnetic actuation. However, these approaches mainly involve physical interactions between the host materials and the relevant stimuli. Herein, a novel, easy‐manipulated, and controllable reconfiguration strategy for polymer architectures is proposed by using a chemical reaction of host material within a hydrogel reactive microenvironment. 3D printed polycaprolactone (PCL) lattices transformed in an aqueous polyacrylamide (PAAm) hydrogel precursor solution, in which ultraviolet (UV) light triggered heterogeneous grafting polymerization between PCL and AAm. In situ microscopy shows that PCL beams go through volumetric expansion and cooperative buckling, resulting in transformation of PCL lattices into sinusoidal patterns. The transformation process can be tuned easily and patterned through the adjustment of the PCL beam diameter, unit cell width, and UV light on–off state. Controlling domain formation is achieved by using UV masks. This framework enables the design, fabrication, and programming of architected materials and inspires the development of novel 4D printing approaches.
Effect of risk and incentives on contracts: The case of farm operators in Iowa
Authors: Lee Jun Yeong 
Published: April 2024

AbstractLongitudinal data on Iowa landowner–operator contracts are used to examine how the mean, variance, and skewness of expected farmland returns affected contract terms from 2008 to 2019. To control for unobserved operator risk preferences and ability as a fixed effect, the sample includes operators with multiple contracts. Our empirical work shows that farmland with lower variance is more likely to be rented for cash, whereas land with highly variable returns is more likely to be custom contracted. [EconLit Citations: L14, Q15]
Spin modulation of single Fe atoms with thiolate‐poisoned Pd nanoclusters for highly efficient ammonia synthesis
Authors: Zhang Bin , Yang Chen , Jia Yunjiao , Nie Guohui , Yang Guidong 
Published: April 2024

AbstractNitrate reduction toward ammonia is pivotal in energy and environmental domains but faces challenges in achieving simultaneous high selectivity and activity. Manipulating interactions between intermediates and metal species is deemed effective for catalytic enhancement. In this study, a uniformly configured Fe1‐N4 single‐atom catalyst with four‐coordination was synthesized. Subsequent deposition of thiol‐poisoned Pd nanoclusters provided a platform to investigate the neighboring effect of Pd nanoclusters, excluding activity influences from Pd catalysts. Through this neighbor engineering, the Fe 3d electron spin configuration shifted from low spin to medium spin (MS). Experimental and theoretical analyses affirmed that MS Fe species optimized nitrate reduction by enhancing the *NO desorption process. This spin‐modulated Fe single‐atom catalyst demonstrated superior activity (392.16 mmol−1 gcat−1 h−1, ~40 mol−1 gFe−1 h−1) and a Faraday efficiency of 98.6% at −0.5 V vs. RHE, surpassing reported values. This study presents a promising strategy for nitrogen‐chemistry transition metal catalysts.
Strategies to Diversification of the Mechanical Properties of Organic Crystals
Authors: Dai Shuting , Zhong Jiangbin , Yang Xiqiao , Chen Chao , Zhou Liping , Liu Xinyu , Sun Jingbo , Ye Kaiqi , Zhang Hongyu , Li Liang , Naumov Panče , Lu Ran 
Published: April 2024

AbstractStructurally ordered soft materials that respond to complementary stimuli are susceptible to control over their spatial and temporal morphostructural configurations by intersectional or combined effects such as gating, feedback, shape‐memory, or programming. In the absence of general and robust design and prediction strategies for their mechanical properties, at present, combined chemical and crystal engineering approaches could provide useful guidelines to identify effectors that determine both the magnitude and time of their response. Here, we capitalize on the purported ability of soft intermolecular interactions to instigate mechanical compliance by using halogenation to elicit both mechanical and photochemical activity of organic crystals. Starting from (E)‐1,4‐diphenylbut‐2‐ene‐1,4‐dione, whose crystals are brittle and photoinert, we use double and quadruple halogenation to introduce halogen‐bonded planes that become interfaces for molecular gliding, rendering the material mechanically and photochemically plastic. Fluorination diversifies the mechanical effects further, and crystals of the tetrafluoro derivative are not only elastic but also motile, displaying the rare photosalient effect.
Enantioselective Nickel‐Catalyzed Denitrogenative Transannulation En Route to N−N Atropisomers
Authors: Ge Fang‐Bei , Lu Chuan‐Jun , Chen Xiao , Yao Wang , An Mei , Jiang Yu‐Kun , Xu Li‐Ping , Liu Ren‐Rong 
Published: April 2024

AbstractNickel‐catalyzed transannulation reactions triggered by the extrusion of small gaseous molecules have emerged as a powerful strategy for the efficient construction of heterocyclic compounds. However, their use in asymmetric synthesis remains challenging because of the difficulty in controlling stereo‐ and regioselectivity. Herein, we report the first nickel‐catalyzed asymmetric synthesis of N−N atropisomers by the denitrogenative transannulation of benzotriazones with alkynes. A broad range of N−N atropisomers was obtained with excellent regio‐ and enantioselectivity under mild conditions. Moreover, density functional theory (DFT) calculations provided insights into the nickel‐catalyzed reaction mechanism and enantioselectivity control.