bluuebunny/crossref_metadata_2025 huggingface dataset:
Hyper NA water immersion lithography at 193nm and 248nm
Authors: Smith Bruce W. , Fan Yongfa , Zhou Jianming , Bourov Anatoly , Zavyalova Lena , Lafferty Neal , Cropanese Frank , Estroff Andrew
Published: December 2004

Immersion lithography can allow for theoretical imaging to λ∕4n (where n is the refractive index of imaging fluid). As 193nm and 248nm technology is pushed toward this limit, experimental data becomes increasingly important. This paper describes research carried out to explore the limitations of water immersion lithography and its extension to higher numerical aperture values using modifications to the imaging fluid. Resist imaging to 38nm is demonstrated using water as an imaging fluid. Several alternative fluids are presented including phosphates, sulfates, and halides, which are shown to increase the refractive index of water.
Simulation and experimental study of polymer deformation in nanoimprint lithography
Authors: Hirai Yoshihiko , Konishi Takaaki , Yoshikawa Takashi , Yoshida Satoshi
Published: December 2004

A polymer deformation process is studied by numerical simulations and the results are compared with the related experimental results in nanoimprint lithography. The imprint pressures required for successful imprinting and the filling rate into the mold grooves are studied as the aspect ratio of the pattern, initial thickness of the polymer, and the duty ratio of the pattern are changed. The required pressure increases not only for high aspect ratio pattern but also low aspect ratio pattern. Also, the pressure increases when the initial thickness of the polymer decreases to less than about two times that of the groove depth of the mold. These results are explained by the deformation mechanism of the polymer and agree well with the related experimental results. Based on these theoretical and experimental studies, fabrication of a high aspect ratio pattern having 100 nm width and 860 nm height is successfully demonstrated using thick polymer by nanoimprint lithography.
Application of ion beam etching technique to the direct fabrication of silicon microtip arrays
Authors: Zhang Xinyu , Tang Qingle , Tang Junming
Published: December 2004

A relatively simple and effective method to directly fabricate large-area field emission microtip arrays on n-type silicon wafers is proposed. The presented fabrication approach of silicon microtip devices mainly involves photolithography, thermal shaping and consolidation, argon ion beam etching and sputtering deposition. The measurements show that the silicon field emission microtip devices fabricated have good structural uniformity and electrical characteristics. The center-to-center spacing of microtips fabricated is 50μm and the typical microtip height about 11μm. The scanning electron microscope analysis and the surface style measurements are carried out for the surface morphologies of silicon microtips, such as square-bottom pyramid-shaped microtips, cone-shaped microtips, square-bottom circle-microtips, and circle-bottom circle-microtips. Electrical measurements are performed to obtain the typical field emission properties of the devices. The experiment results show that the method utilized can be applied to fabricate silicon field emission microtip arrays and circle-microtip arrays of larger area.
Dissolution behavior of main-chain-fluorinated polymers for 157 nm lithography
Authors: Kodani T. , Ishikawa T. , Yoshida T. , Hayami T. , Koh M. , Moriya T. , Yamashita T. , Toriumi M. , Araki T. , Aoyama H. , Hagiwara T. , Furukawa T. , Itani T. , Fujii K.
Published: December 2004

Tetrafluoroethylene-based copolymers with functionalized norbornenes are synthesized by using a fluorocarbon initiator. The effect of molecular weight on the dissolution behavior of five fluoropolymers in a standard alkaline developer is studied using the quartz crystal microbalance method and surface free energy measurements. It is observed that the dissolution rate decreases exponentially with increasing molecular weight for molecular weights under approximately 5000. Swelling is observed in the two polymers that have low surface free energy.
Focused ion beam induced deposition of low-resistivity copper material
Authors: Gannon Thomas J. , Gu George , Casey J. David , Huynh Chuong , Bassom Neil , Antoniou Nicholas
Published: December 2004

Focused ion beam (FIB) induced processes for material etching and deposition have proven successful in integrated circuit device modification applications. Current FIB metal deposition processes are typically limited to resistivities in the range of 150–200μΩcm due to included impurities; however, today’s high-frequency devices require very low interconnect resistivity. The organometallic precursor material copper (I) hexafluoroacetylacetonate trimethylvinylsilane, or Cu(hfac)TMVS for FIB-assisted metal deposition was investigated. 50kV Ga+ ions were scanned over a defined area of an Al∕SiO2 resistivity test substrate in the presence of the precursor vapor, using two different 50kV FIB column designs with beam currents from 49to2070pA and current densities of 13–36Acm−2. Resistivity was measured by the four-point probe method. This study verifies prior reported resistivities of ⩽50μΩcm at room T across all deposition parameters for film growth yields ⩽0.18μm3nC−1 ion dose. Depositing on a heated substrate yields considerably lower film resistivity at temperatures near 100°C; resistivities as low as 18.8μΩcm were achieved at the high growth yield of 0.32μm3nC−1 ion dose. At room temperature, the resistivity varied inversely but nonlinearly with growth yield across all depositions. Auger electron spectroscopy revealed Cu content of ∼60at.% in the lowest resistivity films at all substrate temperatures. Via filling with aspect ratios >9:1 is demonstrated.
Low energy large scan field electron beam column for wafer inspection
Authors: Liu X. , Zhang X. , Zhao Y. , Desai A. , Chen Z. W.
Published: December 2004

A swing objective retarding immersion lens (SORIL) column for wafer inspection is designed and constructed based on SOIL concept. The column consists of a compound retarding electrostatic and magnetic immersion lens and five electrostatic deflectors. The retarding electrostatic and magnetic immersion lens has small spherical and chromatic aberration coefficients for low landing energy. All electrostatic deflectors have a cylindrical duodecapole structure. One deflector is accommodated between the polepiece of the magnetic lens and the specimen surface, and operated at high voltage to fulfill SOIL condition. An on-axis annular semiconductor detector with a small opening in the center is employed to collect signal electrons. The annular detector achieves high collection efficiency over a large scan field. Experimental results show that the SORIL column has accomplished a 600μm×600μm scan field with 0.1μm maximum spot size in a wide landing energy range (from 200to2000eV) without dynamic aberration correction or dynamic focusing. Resolution of 15nm is achieved in a 50μm×50μm scan field. The probe beam current delivered by the SORIL column is from a few nA to more than 100nA because of the specially designed bright electron gun. The SORIL column has been installed onto HMI’s electron beam wafer inspection tool, eScan™ 300. The SORIL’s optical performances enable eScan™ 300 to be a powerful electron beam wafer inspection and in-line process monitoring tool.
Stamps for nanoimprint lithography by extreme ultraviolet interference lithography
Authors: Park Sunggook , Schift Helmut , Solak Harun H. , Gobrecht Jens
Published: December 2004

Extreme ultraviolet interference lithography (EUV-IL) was employed to fabricate large area stamps with patterns of sub-50nm half pitch for nanoimprint lithography (NIL). The resist patterns exposed by EUV-IL were transferred into underlying Si or SiO2∕Si substrates by reactive ion etching. With this method, NIL stamps with feature sizes as small as 25nm and patterned areas as large as 1×1mm2 were successfully produced. Using those stamps in NIL, the patterns with aspect ratio up to 2 were replicated with good replication fidelity. Increasing aspect ratio for the stamp patterns first results in distortion and discontinuity and then, the ripping of partial structures in the imprinted patterns.
Activity-Dependent Internalization of Smoothened Mediated by ß-Arrestin 2 and GRK2
Authors: Chen Wei , Ren Xiu-Rong , Nelson Christopher D. , Barak Larry S. , Chen James K. , Beachy Philip A. , de Sauvage Frederic , Lefkowitz Robert J.
Published: December 2004

Binding of Sonic Hedgehog (Shh) to Patched (Ptc) relieves the latter's tonic inhibition of Smoothened (Smo), a receptor that spans the cell membrane seven times. This initiates signaling which, by unknown mechanisms, regulates vertebrate developmental processes. We find that two molecules interact with mammalian Smo in an activation-dependent manner: G protein–coupled receptor kinase 2 (GRK2) leads to phosphorylation of Smo, and β-arrestin 2 fused to green fluorescent protein interacts with Smo. These two processes promote endocytosis of Smo in clathrin-coated pits. Ptc inhibits association of β-arrestin 2 with Smo, and this inhibition is relieved in cells treated with Shh. A Smo agonist stimulated and a Smo antagonist (cyclopamine) inhibited both phosphorylation of Smo by GRK2 and interaction of β-arrestin 2 with Smo. β-Arrestin 2 and GRK2 are thus potential mediators of signaling by activated Smo.
Detection of a Deep 3-µm Absorption Feature in the Spectrum of Amalthea (JV)
Authors: Takato Naruhisa , Bus Schelte J. , Terada Hiroshi , Pyo Tae-Soo , Kobayashi Naoto
Published: December 2004

Near-infrared spectra of Jupiter's small inner satellites Amalthea and Thebe are similar to those of D-type asteroids in the 0.8- to 2.5-micrometer wavelength range. A deep absorption feature is detected at 3 micrometers in the spectra of the trailing side of Amalthea, which is similar to that of the non-ice components of Callisto and can be attributed to hydrous minerals. These surface materials cannot be explained if the satellite formed at its present orbit by accreting from a circumjovian nebula. Amalthea and Thebe may be the remnants of Jupiter's inflowing building blocks that formed in the outer part or outside of the circumjovian nebula.
Toward Better Drugs for Less
Authors: Kessler Daniel Philip
Published: December 2004

The Truth About the Drug CompaniesHow They Deceive Us and What To Do About It .by Marcia Angell. Random House, New York, 2004. 325 pp. $24.95, C$34.95. ISBN 0-375-50846-5.

Powerful MedicinesThe Benefits, Risks, and Costs of Prescription Drugs.By Jerry Avorn. Knopf, New York, 2004. 457 pp. $27.50, C$39.95. ISBN 0-375-41483-5.

Angell offers an expose of the pharmaceutical industry, which she describes as "primarily a marketing machine to sell drugs of dubious benefit." Avorn discusses how prescription drugs are approved, promoted, and used. To contain costs, he argues for an agenda of comparative studies that would inform physicians, patients, and those who pay the bills.
ELECTROMAGNETIC MESON PRODUCTION IN THE NUCLEON RESONANCE REGION
Authors: BURKERT V. D. , LEE T.-S. H.
Published: December 2004

Recent experimental and theoretical advances in investigating electromagnetic meson production reactions in the nucleon resonance region are reviewed. We give a description of current experimental facilities with electron and photon beams and present a unified derivation of most of the phenomenological approaches being used to extract the resonance parameters from the data. The analyses of π and η production data and the resulting transition form factors for the Δ(1232)P33, N (1535)S11, N (1440)P11, and N (1520)D13 resonances are discussed in detail. The status of our understanding of the reactions with production of two pions, kaons, and vector mesons is also reviewed.
TEMPERATURE DEPENDENCE OF NUCLEAR STRUCTURE IN THE RELATIVISTIC MEAN-FIELD THEORY WITH A NEW PARAMETER SET
Authors: NERLO-POMORSKA BOŻENA , POMORSKI KRZYSZTOF , SYKUT JOANNA , BARTEL JOHAN
Published: December 2004

A new set of relativistic mean-field theory (RMFT) parameters, NL4, ensuring a better description of the average nuclear energy as given by the new Lublin–Strasbourg mass formula, is used in a self-consistent description of 171 spherical even-even nuclei at temperatures 0≤T≤4 MeV. Single-particle level densities for this sample of nuclei are determined by analyzing the data obtained for various temperatures. The average dependence of the single-particle level density on mass number A and isospin is given and compared with previous estimates obtained using the RMFT-NL3, Thomas–Fermi and semiclassical Skyrme SkM* approaches.
SELF-SIMILAR AND SELF-AFFINE PIONIZATION IN NUCLEAR INTERACTIONS AT A FEW AGeV
Authors: GHOSH DIPAK , DEB ARGHA , DUTTA (CHATTOPADHYAY) KEYA , SARKAR RINKU , SEN (DUTTA) ISHITA
Published: December 2004

Self-affine multiplicity scaling is investigated in the framework of two-dimensional factorial moment methodology using the concept of the Hurst exponent (H) considering different bins of the phase space. We have investigated the fluctuation pattern of emitted pions in 24 Mg - AgBr interactions at 4.5 AGeV and this study reveals that the fluctuation is self-similar in some bins, whereas it is self-affine in other bins, that is, the multiplicity scaling is bin-dependent.
NEUTRINOLESS DOUBLE BETA DECAY: CURRENT STATUS AND PERSPECTIVES. THE CAMEO PROJECT
Authors: MIRAMONTI LINO
Published: December 2004

0ν2β decay is a very powerful tool for probing the physics beyond the particle Standard Model. After the recent discovery of neutrino flavor oscillation, we know that neutrinos must have a mass (at least two of them). The 0ν2β decay discovery could fix the neutrino mass scale and its nature (Majorana particle). The unique characteristics of the Borexino detector and its Counting Test Facility (CTF) can be employed for high sensitivity studies of 116 Cd 0ν2β decay: the CAMEO project. A first step foresees 24 enriched 116 CdWO 4 crystals for a total mass of 65 kg in the Counting Test Facility; then, 370 enriched 116 CdWO 4 crystals, for a total mass of 1 ton in the Borexino detector. Measurements of 116 CdWO 4 crystals and Monte Carlo simulations have shown that the CAMEO experiment sensitivity will be [Formula: see text], for the 65 kg phase, and [Formula: see text] for the 1 ton phase; consequently the limit on the effective neutrino mass will be ≤ 60 meV, and ≤ 20 meV, respectively. This work is based upon the experiments performed by the INR (Kiev) (and from 1998 also by the University of Florence) at the Solotvina Underground Laboratory (Ukraine). The current status of 0ν2β, and future projects of 0ν2β decay research are also briefly reviewed.
NEUTRON EMISSION SPECTRA OF EXCITED 126–140Sn NUCLEI
Authors: AGGARWAL MAMTA , RAJASEKARAN M.
Published: December 2004

We investigate one-neutron and two-neutron emission from 132 Sn and its neighboring isotopes due to thermal excitation. The rotational states of 132 Sn at different temperatures are investigated. The effects of separation energy and thermal excitation energy on neutron emission probability are studied.
INTERVAL METHODS IN KNOWLEDGE REPRESENTATION
Authors: KREINOVICH VLADIK
Published: December 2004

This section is maintained by Vladik Kreinovich. Please send your abstract (or copies of papers that you want to see reviewed here), to vladik@cs.utep.edu, or by regular mail to: Vladik Kreinovich, Department of Computer Science, University of Texas at El Paso, El Paso, TX 79968, USA.
Elastic Cycles as Flexible Hosts: How Tubes Built by Cyclic Chalcogenaalkynes Individually Host Their Guests
Authors: Gleiter Rolf , Werz Daniel B
Published: December 2004

Tubular structures arise in the solid state through close chalcogen–chalcogen contacts. Several examples containing sulfur and selenium centers are presented. In the case of cyclic systems of ring size 22–33 the resulting tubes are capable of including π-systems as guest molecules. For hexaselenacyclotriacontahexayne 8(5) it is shown that the cycle is flexible and adopts a smaller space in the case of furan or n-hexane as compared with that of mesitylene. This behavior is attributed to the relatively low torsional barrier at the chalcogen-substituted butadiyne unit.
N-Alkylation of Phthalimide, Carboxamide, and Sulfonamides By Oxdation–Reduction Condensation Using Di-tert-butyl-1,4-benzoquinone and Alkyl Diphenylphosphinite
Authors: Mukaiyama Teruaki , Aoki Hidenori
Published: December 2004

Various N-alkylamides were obtained in high yields under mild conditions by treating alkyl diphenylphosphinite with phthalimide, carboxamide or sulfonamides in the presence of 2,6-di-tert-butyl-1,4-benzoquinone (DBBQ) by oxdation–reduction condensation.
Fabrication of a Novel Nanodevice That Functions on Demand
Authors: Oba Toru , Hanasaki Mitsuru , Minabe Masahiro , Tamiaki Hitoshi
Published: December 2004

A novel nanodevice that had a well-defined nanostructure was fabricated by utilizing cytoskeleton ‘microtubule.’ The device can function on demand, as well as be reusable, repairable, and modifiable. The present study may lead to fabrication of elaborate (supra)molecular systems, such as self-healing materials.
Facile Synthesis of Uniform Tungsten Oxide Nanorods in Large Scale
Authors: Zhang Bing , Cao Chuanbao , Qiu Hailin , Xu Yajie , Wang Yingchun , Zhu Hesun
Published: December 2004

The uniform tungsten oxide nanorods have been synthesized in large scale simply by heating a treated foil of tungsten. The diameter of the nanorods ranged from 100 to 300 nm and the length was up to 10 μm.
Oxidation of Cyclohexane over Bi-incorporated MCM-41 Mesoporous Molecular Sieve Catalyst with Oxygen as Oxidant
Authors: Qian Guang , Lu Gaomeng , Ji Dong , Zhao Rui , Qi Yanxing , Suo Jishuan
Published: December 2004

Bismuth-incorporated MCM-41, which was directly synthesized under strongly acidic conditions and characterized, for the first time, by XRD, UV–vis and Raman spectroscopy, was used as catalyst for the oxidation of cyclohexane without organic solvent using O2 as oxidant, and the results of reaction indicate that Bi-MCM-41 is a very stable and efficient catalyst.
A Core-shell Nanostructure of Carbon
Authors: Luo Tao , Yang Xiaogang , Liu Jianwei , Yu Weichao , Qian Yitai
Published: December 2004

Core-shell structured carbon nanospheres with 300–500 nm in diameter have been synthesized at 600 °C by reducing ethyl ether with metallic magnesium.
Improving locomotive syndrome risk level through community‐led activities to establish walking habits
Authors: Matsushita Daisuke , Gu Yangcheng
Published: February 2024

We evaluated the effects of walking habits and mobility improvement on an aging population among 30 residents of a suburban residential complex with the aim of promoting sustainable health activities led by residents. The results showed a total of 911 person‐days of actual walking (Mean = 30.4, Standard Deviation = 15.7) with an average of 30 days per person or a frequency of almost daily intervals over 2 months. In total, 68.4% of early‐ and 54.5% of late‐elderly participants met the recommended criteria for healthy older adults. The results of the GLFS‐25 and 2‐step tests showed a significant improvement in the mobility function after the walking period compared to before the walking period. In addition to the improvements in physical mobility, there were improvements in social interactions and participation in community activities. The participants' post‐walking effect showed that 85% of them were in good health, 50% had positive social interactions, and 25% had positive statements regarding community and town planning. The results verified that resident‐led sustainable walking activities can establish walking habits and improve mobility.
Transfer learning for forecasting hourly indoor air temperatures of buildings with electrochromic glass
Authors: Srisamranrungruang Thanyalak , Hiyama Kyosuke
Published: February 2024

This study aimed to employ transfer learning with a fully connected feed‐forward neural network for forecasting the indoor air temperatures of adaptive buildings with electrochromic (EC) glass. This study predicted indoor air temperatures for an intermediate season requiring heating and cooling. Forecasting indoor air temperature can help control the EC glass to avoid overheating the interiors. The forecasting times for the predictions varied from 1 to 5 h between early morning and noon, which is when the interior is often overheated. The pretrained model was created using multilayer perceptron learning with the simulation data of a source building in Tokyo and transfer learning with feature‐based extraction models that used datasets from the simulation of target buildings in Tokyo and Fukuoka. Further, the effects of facade orientation were investigated. The root mean squared error (RMSE) of the pretrained model varied from 0.027 to 0.935 when predicting the indoor air temperatures from 1 to 5 h. The RMSE of the transfer learning models using the pretrained model with the same and different orientations varied from 0.022 to 1.205 and from 0.9301 to 2.566. This study demonstrated that utilizing predicted indoor air temperatures to control EC glass can help protect against overheating.
Influence of the Phase Fractions on the Formation of Eutectic Colonies: A Large‐Scale Phase‐Field Study
Authors: Kellner Michael , Hierl Henrik , Nestler Britta
Published: February 2024

The growth of two‐phase eutectic colonies is a frequently observed phenomenon in the microstructure of directionally solidified ternary alloys. The formation of these macroscopic structures is driven by microscopic instabilities, caused by minor component impurities, diffusing into the liquid from the two solidifying phases. Due to an accumulation of this impurity component, a morphological instability at the eutectic front leads to the formation of eutectic colonies. In this work, the phase‐field method is used to investigate the influence of different melt composition and hence of the adjusting phase fractions on the growth of eutectic colonies. For this purpose, specially designed model systems, N‐xA‐yC, with defined phase fractions of the solids are generated on the basis of the high performance material NiAl‐34Cr. Based on these models, the evolution of eutectic colonies is investigated in two‐ and three‐dimensional (3D) large‐scale simulations with up to 3⋅109 cells. To perform these highly computationally intense large‐scale 3D simulations, the computational framework used is optimized in several layers. The results obtained show the influence of the melt composition on the formation and characteristics of the evolved eutectic colonies and provide new insights into the formation of these macroscopic structures.
Vibration‐Enabled Mobility of Liquid Metal
Authors: Handschuh‐Wang Stephan , Gan Tiansheng , Wang Tao , He Bin , Han Peigang , Stadler Florian J. , Zhou Xuechang
Published: February 2024

Directed liquid metal (gallium‐based) manipulation and actuation are paramount for copious applications, including soft robotics, soft electronics, and targeted drug delivery. Although there are several strategies available to achieve mobility of liquid metals in a “wet” environment. Strategies to achieve and improve mobility of liquid metal droplets and puddles in a “dry” environment are scarce and rely on metallophobic surface design or liquid metal marbles. Here, high mobility of Galinstan is elucidated by combining metallophobic surface design and vertical vibrations. Vibration frequencies between 20 and 30 Hz are conducive to droplet movement and threshold inclination angles of 0.5° to 1° are observed upon actuation by these vibrations. The method itself is applicable for a wide range of droplet sizes (30 and 2000 µL) and very robust. The droplet movement typically comprises of periodic receding and advancing of the droplet and commences via a rolling mechanism rather than a gliding mechanism. Finally, it is shown that small (0.5 mm height) obstacles can be traversed by this method, indicating that it can be used in concert with other strategies, such as surface structuring strategies, which open up pathways for mobility and controlled actuation of liquid metal droplets in air.
Glucose Epimerization‐Modulated Phytochemicals Constructing Carrier‐Free Hydrogel for Regulation of Macrophage Phenotype to Promote Wound Healing
Authors: Lu Jihui , Zhao Haoqiang , Wang Zhijia , Lin Xiaoyu , Pi Wenmin , Zhang Xiang , Yang Luping , Yao Shuchang , Zhang Yaozhi , Huang Xuemei , Lei Haimin , Wang Penglong
Published: February 2024

The self‐assembly of phytochemicals with multiple chiral centers is receiving significant attention for its potential in biomedical applications. However, the impact of single chiral center epimerization on molecular self‐assembly remains unexplored. Herein, the self‐assembly behavior and bioactivities of 1,2,3,4,6‐penta‐O‐galloyl‐α‐D‐glucose (α‐D‐PGG) and 1,2,3,4,6‐penta‐O‐galloyl‐β‐D‐glucose (β‐D‐PGG) is examined, a pair of natural ellagitannins abundant in plants. Interestingly, β‐D‐PGG formed a hydrogel without modification, while α‐D‐PGG does not. This occurred due to the balanced distribution of aromatic rings and phenolic hydroxyl groups in β‐D‐PGG, facilitating self‐assembly via hydrogen bonding and π–π stacking into nanofibers. In contrast, α‐D‐PGG's self‐assembly is inhibited by steric hindrance. Notably, β‐D‐PGG hydrogel demonstrated exceptional antibacterial activity and by regulating macrophage polarization toward the M2 phenotype, thereby reducing inflammation. This study not only reveals the distinct self‐assembly behaviors of glucose derivatives but also offers new insights into their potential in biomedical applications, such as wound healing.
Laser Ablation‐Induced Boron Nitride Aerogels with Intrinsic Photoluminescence for Efficient Information Encryption
Authors: Li Guangyong , Chai Yushan , Zhang Xuetong
Published: February 2024

Boron nitride (BN) aerogels, dual interconnecting network of BN nanoscale building blocks, and plenty of air within these nanoscale building blocks, have great potential in many emerging fields. However, fast synthesis and emerging applications, e.g., information encryption, are still challenging for advancing BN aerogels. Herein, intrinsic photoluminescent BN aerogels with programmable patterns are developed via laser ablating of melamine diborate (M2B) aerogel. The obtained BN aerogel exhibited typical hollow‐microsphere structures and blue fluorescence phenomenon, which are totally different from BN aerogels reported elsewhere. This BN aerogel exhibited excellent thermal insulation properties (0.027 W mK−1), transient fluorescence feature (3 ns average radiative lifetime), high quantum yield (18.45%), and excellent weather ability (e.g., resistance to high temperature, solar irradiation, and humidness). By programming the laser moving path, different fluorescent patterns (e.g., various security labels, secret matching keys, quick response codes) of BN aerogels can be processed, which promises excellent information encryption in the field of Internet of Things, etc. The results may inspire researchers to fabricate more aerogels with this fast laser‐ablation strategy and the resulting intrinsic fluorescent BN aerogels may find significant applications in some emerging fields.
Gradient Nanotwins and Enhanced Weighted Mobility Synergistically Upgrade Bi0.5Sb1.5Te3 Thermoelectric and Mechanical Performance
Authors: Pang Kaikai , Miao Liya , Zhang Qiang , Pan Qiaoyan , Liu Yan , Shi Huilie , Li Jingsong , Zhou Wenjie , Zhang Zongwei , Zhang Yuyou , Wu Gang , Tan Xiaojian , Noudem Jacques G. , Wu Jiehua , Sun Peng , Hu Haoyang , Liu Guo‐Qiang , Jiang Jun
Published: February 2024

Bi2Te3‐based alloys have historically dominated the commercial realm of near room‐temperature thermoelectric (TE) materials. However, the more widespread application is currently constrained by its mediocre TE performance and inferior mechanical properties resulting from intrinsic hierarchical structure. Herein, microstructure modulation and carrier transport optimization strategies are employed to efficiently balance the electro‐thermal transport performance. Specifically, the weighted mobility increases by 24%, while the lattice thermal conductivity decreases by 31% at 350 K compared to the matrix. Consequently, the Bi0.5Sb1.496Cu0.004Te2.98 sample attains a peak ZT of 1.45 at 350 K and an average ZT of 1.20 (300–500 K). Moreover, intricated microstructure design, exemplified by the gradient twin structure, significantly enhances the mechanical performance metrics, including Vickers hardness, compressive strength, and bending strength, to notable levels of 0.94 GPa, 224 MPa, and 58 MPa, respectively. Consequently, the constructed 17‐pair TE modules demonstrate a maximum conversion efficiency of 6.5% at ΔT = 200 K, surpassing the majority of reported Bi2Te3‐based modules. This study provides novel insights into the synergistic enhancement of TE and mechanical properties in Bi2Te3‐based materials, with potential applicability to other TE systems.
Blocking the Dendrite‐Growth of Zn Anode by Constructing Ti4O7 Interfacial Layer in Aqueous Zinc‐Ion Batteries
Authors: Song Yang , Liu Yongduo , Luo Shijian , Yang Yuran , Chen Fadong , Wang Meng , Guo Lin , Chen Siguo , Wei Zidong
Published: February 2024

Zinc metal is a promising choice as a high‐capacity and cost‐effective anode for aqueous zinc‐based batteries. However, it faces challenges related to low cycling stability and poor reversibility due to parasitic reactions and the growth of zinc dendrites. In this study, a solution is proposed by introducing a conductive Ti4O7 layer on the zinc anode to enhance electrode stability. The Ti4O7 layer serves a dual purpose, effectively preventing spontaneous corrosion of the zinc anode in the electrolyte, thereby inhibiting the hydrogen evolution reaction and the generation of byproducts. Simultaneously, it promotes Zn nucleation and ensures a uniform electric field distribution, resulting in homogeneous Zn plating and stripping compared to using a bare zinc anode. Consequently, the Ti4O7‐coated Zn anode experiences a significant reduction in over‐potential, demonstrating long‐term stability and dendrite‐free behavior. This outcome ensures low polarization potential and high cycling stability in zinc‐ion batteries. The work underscores the potential of conductive oxides in the development of stable metal electrodes.
MAX Phase Ti2AlN for HfO2 Memristors with Ultra‐Low Reset Current Density and Large On/Off Ratio
Authors: Athena Fabia F. , Nnaji Moses , Vaca Diego , Tian Mengkun , Buchmaier Wolfgang , Aabrar Khandker Akif , Graham Samuel , Datta Suman , Kumar Satish , Vogel Eric M.
Published: February 2024

A Ti2AlN MAX phase layered thin film electrode and oxygen getter layer for HfO2‐based two‐terminal memristors is presented. The Ti2AlN/HfOx/Ti memristor devices exhibit enhanced resistive switching performance, including an ultra‐low reset current density (< 10−8 MΩ cm2), substantial on‐off ratio (≈ 6000), excellent multi‐level functionality (≈ 9 distinct states), impressive retention (up to 300 °C), and robust endurance (>200 million) as compared to conventional TiN and other alternative materials based memristors. Experimental measurements and modeling suggest that the distinctive combination of low thermal conductivity, high electrical conductivity, and unique ultra‐thin layer‐by‐layer structure of the Ti2AlN MAX phase thin film contribute to this exceptional performance with good reproducibility and stability. The results demonstrate for the first‐time the potential of this innovative sputtered MAX phase material for engineering energy‐efficient, high‐density non‐volatile digital, and analog memory devices aimed toward next‐generation sustainable artificial intelligence.
A Molecule Crowding Strategy to Stabilize Aqueous Sodium‐Ion Batteries
Authors: Ding Jibo , Li Qin , Yang Jinyu , Wang Runting , Ruan Jiafeng , Fang Fang , Sun Dalin , Wang Fei
Published: February 2024

Aqueous sodium‐ion batteries (ASIBs) have recently emerged as a compelling choice for large‐scale energy storage when considering their safe operational characteristics and cost‐effectiveness. Nonetheless, the inadequate electrochemical stability window (ESW) of water (1.23 V) and severe dissolution of electrodes in aqueous electrolytes have proven bottlenecks to enabling high energy density and long lifespan of ASIBs. Here, a molecular crowding electrolyte is introduced, featuring nonflammable polyethylene glycol dimethyl ether (PED) as a crowding agent and a hydrogen bond receptor to further diminish the water activity. The 4.5 m (mol kg−1) NaClO4‐4 wt% H2O‐96 wt% PED electrolyte displayed an impressive ESW of 3.4 V, all while maintaining a moderate salt concentration of 4.5 m. Meanwhile, this electrolyte demonstrated substantial mitigation of vanadium dissolution in Na3V2(PO4)3. Consequently, in a comprehensive evaluation, the aqueous NaTi2(PO4)3||Na3V2(PO4)3 full cell exhibited an energy density of 47 Wh kg−1 at 1 C with a 74% retention after 100 cycles, and displayed negligible capacity decay (≈0.014% per cycle) at 5 C in 1000 cycles with high average coulombic efficiency of 99.8%. This work offers a universal strategy for the design of aqueous electrolytes with wide ESW and the ability to effectively suppress vanadium dissolution.
Coagulant Protein‐Free Blood Coagulation Using Catechol‐Conjugated Adhesive Chitosan/Gelatin Double Layer
Authors: Kim Soomi , Kim Keumyeon , Koh Mi‐Young , Do Minjae , Lee Moon Sue , Ryu Ji Hyun , Lee Haeshin
Published: February 2024

Since the discovery of polyphenolic underwater adhesion in marine mussels, researchers strive to emulate this natural phenomenon in the development of adhesive hemostatic materials. In this study, bio‐inspired hemostatic materials that lead to pseudo‐active blood coagulation, utilizing traditionally passive polymer matrices of chitosan and gelatin are developed. The two‐layer configuration, consisting of a thin, blood‐clotting catechol‐conjugated chitosan (CHI‐C) layer and a thick, barrier‐functioning gelatin (Geln) ad‐layer, maximizes hemostatic capability and usability. The unique combination of coagulant protein‐free condition with CHI‐C showcases not only coagulopathy‐independent blood clotting properties (efficacy) but also exceptional clinical potential, meeting all necessary biocompatibility evaluation (safety) without inclusion of conventional coagulation triggering proteins such as thrombin or fibrinogen. As a result, the CHI‐C/Geln is approved by the Ministry of Food and Drug Safety (MFDS, Republic of Korea) as a class II medical device. Hemostatic efficacy observed in multiple animal models further demonstrates the superiority of CHI‐C/Geln sponges in achieving quick hemostasis compared to standard treatments. This study not only enriches the growing body of research on mussel‐inspired materials but also emphasizes the potential of biomimicry in developing advanced medical materials, contributing a promising avenue toward development of readily accessible and affordable hemostatic materials.
Cell Membrane‐Targeting Type I/II Photodynamic Therapy Combination with FSP1 Inhibition for Ferroptosis‐Enhanced Photodynamic Immunotherapy
Authors: Chen Jian , Duan Zeyu , Deng Lidong , Li Lie , Li Qiyan , Qu Jinqing , Li Xiang , Liu Ruiyuan
Published: February 2024

An imbalance in reactive oxygen species (ROS) levels in tumor cells can result in the accumulation of lipid peroxide (LPO) which can induce ferroptosis. Moreover, elevated ROS levels in tumors present a chance to develop ROS‐based cancer therapeutics including photodynamic therapy (PDT) and ferroptosis. However, their anticancer efficacies are compromised by insufficient oxygen levels and inherent cellular ROS regulatory mechanism. Herein, a cell membrane‐targeting photosensitizer, TBzT‐CNQi, which can generate 1O2, •OH, and O2•− via type I/II process to induce a high level of LPO for potent ferroptosis and photodynamic therapy is developed. The FSP1 inhibitor (iFSP1) is incorporated with TBzT‐CNQi to downregulate FSP1 expression, lower the intracellular CoQ10 content, induce a high level of LPO, and activate initial tumor immunogenic ferroptosis. In vitro and in vivo experiments demonstrate that the cell membrane‐targeting type I/II PDT combination with FSP1 inhibition can evoke strong ICD and activate the immune response, which subsequently promotes the invasion of CD8+ T cells infiltration, facilitates the dendritic cell maturation, and decreases the tumor infiltration of tumor‐associated macrophages. The study indicates that the combination of cell membrane‐targeting type I/II PDT and FSP1 inhibition holds promise as a potential strategy for ferroptosis‐enhanced photodynamic immunotherapy of hypoxia tumors.
A Catalyst‐Like System Enables Efficient Perovskite Solar Cells
Authors: Yang Yuqian , Li Guodong , Zhao Lichen , Tan Pengju , Li Yu , Li Shunde , Tan Lina , Deng Chunyan , Wang Shibo , Zhao Zhenzhu , Yuan Chengjian , Ding Honghe , Chen Liang , Zhu Junfa , Guan Yong , Hou Cheng‐Hung , Tang Pengyi , Li Quiyang , Liu Hong , Yang Yingguo , Abate Antonio , Shyue Jing‐Jong , Wu Jihuai , Russell Thomas P. , Hu Qin
Published: February 2024

High‐quality perovskite films are essential for achieving high performance of optoelectronic devices; However, solution‐processed perovskite films are known to suffer from compositional and structural inhomogeneity due to lack of systematic control over the kinetics during the formation. Here, the microscopic homogeneity of perovskite films is successfully enhanced by modulating the conversion reaction kinetics using a catalyst‐like system generated by a foaming agent. The chemical and structural evolution during this catalytic conversion is revealed by a multimodal synchrotron toolkit with spatial resolutions spanning many length scales. Combining these insights with computational investigations, a cyclic conversion pathway model is developed that yields exceptional perovskite homogeneity due to enhanced conversion, having a power conversion efficiency of 24.51% for photovoltaic devices. This work establishes a systematic link between processing of precursor and homogeneity of the perovskite films.
Selective Induction of Molecular Assembly to Tissue‐Level Anisotropy on Peptide‐Based Optoelectronic Cardiac Biointerfaces
Authors: Yao Ze‐Fan , Kuang Yuyao , Wu Hao‐Tian , Lundqvist Emil , Fu Xin , Celt Natalie , Pei Jian , Yee Albert F. , Ardoña Herdeline Ann M.
Published: February 2024

The conduction efficiency of ions in excitable tissues and of charged species in organic conjugated materials both benefit from having ordered domains and anisotropic pathways. In this study, a photocurrent‐generating cardiac biointerface is presented, particularly for investigating the sensitivity of cardiomyocytes to geometrically comply to biomacromolecular cues differentially assembled on a conductive nanogrooved substrate. Through a polymeric surface‐templated approach, photoconductive substrates with symmetric peptide‐quaterthiophene (4T)‐peptide units assembled as 1D nanostructures on nanoimprinted polyalkylthiophene (P3HT) surface are developed. The 4T‐based peptides studied here can form 1D nanostructures on prepatterned polyalkylthiophene substrates, as directed by hydrogen bonding, aromatic interactions between 4T and P3HT, and physical confinement on the nanogrooves. It is observed that smaller 4T‐peptide units that can achieve a higher degree of assembly order within the polymeric templates serve as a more efficient driver of cardiac cytoskeletal anisotropy than merely presenting aligned ‐RGD bioadhesive epitopes on a nanotopographic surface. These results unravel some insights on how cardiomyocytes perceive submicrometer dimensionality, local molecular order, and characteristics of surface cues in their immediate environment. Overall, the work offers a cardiac patterning platform that presents the possibility of a gene modification‐free cardiac photostimulation approach while controlling the conduction directionality of the biotic and abiotic components.
Phenothiazine Derivatives as Small‐Molecule Organic Cathodes with Adjustable Dropout Voltage and Cycle Performance
Authors: Gong Yanxiang , Zhang Weichao , Liu Zhenjiang , Fang Manman , Yang Jie , Wang Yunsheng , Gao Mingxue , Zhang Jun , Yang Quan‐Hong , Li Zhen
Published: February 2024

Compared with conventional inorganic materials, organic electrodes are competitive candidates for secondary battery cathodes due to their resourcefulness, environmental friendliness, and cost‐effectiveness. Much effort is devoted at the level of chemical structure, while ignoring the impact of molecular aggregation on battery behavior. Herein, this work designs a series of organic molecules with two electrochemically active phenothiazine groups linked by different lengths of alkyl chain to regulate molecular symmetry and crystallinity. The results emphasize the equally important role of molecular aggregation and chemical structure for battery performance. Among them, 2PTZ‐C7H14|Li cell exhibits the most impressive cycle and rate performance. At the high rate of 50 C, it can still deliver a capacity of 63.4 mA h g−1 and 74.5% capacity retention after 10 000 cycles. Besides, the dropout voltage of 2PTZ‐C9H18|Li cell is only 52 mV, which is among the lowest reported for lithium‐organic batteries to the best of the author's knowledge.
Angle‐Independent Top‐Emitting Quantum‐Dot Light‐Emitting Diodes Using a Solution‐Processed Subwavelength Scattering–Capping Layer
Authors: Lee Taesoo , Lee Minhyung , Kim Kyuho , Lee Hyunkoo , Yoon Suk‐Young , Yang Heesun , Yu Sunkyu , Kwak Jeonghun
Published: February 2024

Owing to the excellent optoelectronic properties of colloidal quantum dots (QDs), light‐emitting diodes based on QDs (QLEDs) have been considered one of the most promising electroluminescence (EL) devices for full‐color displays with a wide color gamut. Particularly, top‐emission device architecture has been of interest to both academia and industry, because of the advantages in light outcoupling, aperture ratios, and integration with conventional backplanes. In this structure, however, angle‐dependent color shifts originating from a variation in microcavity length are a critical issue that needs to be resolved. Here, a solution‐processed dual‐functional scattering–capping layer (SCPL) using ZnO nanoparticles on top‐emitting QLEDs with ZnSeTe/ZnSe/ZnS QDs to modulate the optical interference is presented. By precisely controlling the thickness of the SCPL, the EL intensity and spectrum can be redistributed to produce a uniform color from any viewing angle. It is discovered that, unlike conventional CPLs, the formation of random nanocracks and nanoclusters in the SCPL adds subwavelength light‐scattering capabilities, which promotes light extraction. The QLEDs with the solution‐processed SCPL exhibit a 44% increase in the maximum external quantum efficiency, with completely imperceptible angle‐dependent spectral shifts. The SCPL is expected to be applied to the development of high‐performance and next‐generation QLED displays.
A core–shell‐structured zeolitic imidazolate framework@cationic antimicrobial agent templated silica nanocomposite for tackling antibiotic resistant bacteria infection
Authors: Kan Qihui , Song Yaping , Yao Yining , Zhang Jun , Xian He , Cheng Dan , Wang Yue , Mao Liang , Wang Meiyan , Yu Chengzhong
Published: February 2024

Bacterial infection is a major threat to public health. Nanotechnology offers a solution by combining nanomaterials with antibacterial agents. The development of an effective nanocomposite against drug‐resistant bacteria such as methicillin‐resistant Staphylococcus aureus (MRSA) is highly important yet challenging. Here, an anti‐MRSA core–shell structure is designed, containing antibacterial zeolitic imidazolate framework‐8 (ZIF‐8) as the core and bactericidal benzalkonium chloride (BAC) templated rough‐surface mesostructured silica nanocomposite (RMSN) as the shell. The resultant ZIF‐8@RMSN nanocomposite exhibits sustained release of BAC and zinc ions, effective disruption of the bacterial membrane, generation of oxidative damage of bacterial DNA, leakage of intracellular components, and finally bacterial death. Furthermore, the synergistic antibacterial mechanisms lead to enhanced biofilm elimination performance. In addition, the ZIF‐8@RMSN‐modified band‐aid effectively combats MRSA infection in vivo. This work has provided a promising nanocomposite against MRSA‐related infections.
Data‐driven identification of crystallization kinetics
Authors: Nyande Baggie W. , Nagy Zoltan K. , Lakerveld Richard
Published: February 2024

A novel data‐driven methodology is presented for developing mathematical models for crystallization processes. The data‐driven approach is based on the sparse identification of nonlinear dynamics (SINDy) method, which iterates between a partial least‐squares fit and a sparsity‐promoting step leading to the discovery of sparse interpretable models. The performance of the SINDy methodology is characterized for the identification of crystallization kinetics in a mixed tank operated in a continuous mode, the isothermal crystallization of lysozyme in a batch stirred tank and cooling crystallization of paracetamol. The SINDy method is robust against noise. Good agreement is obtained between the data‐driven model and the data obtained from crystallization experiments. The presented data‐driven approach can be attractive for modeling industrial crystallization processes where process analytical technology tools are available for the measurement of process variables but functional forms of kinetic expressions are unknown.
sp‐Carbon‐Conjugated Organic Polymer as Multifunctional Interfacial Layers for Ultra‐Long Dendrite‐Free Lithium Metal Batteries
Authors: Lu Xiao‐Meng , Cao Yingnan , Sun Yi , Wang Haichao , Sun Weiwei , Xu Yi , Wu Yang , Yang Chao , Wang Yong
Published: February 2024

Fatal issues in lithium metal anodes (LMA), such as detrimental lithium dendrites growth and fragile solid‐electrolyte interphase (SEI) during the Li plating/stripping process, often hinder the practical application of Li metal batteries (LMBs). Herein, cobalt‐coordinated sp‐carbon‐conjugated organic polymer (Co‐spc‐COP) is constructed as the protective layer for regulating the interface stability of LMA. The unique synergistic beneficial effect of organic functional groups (C≡C linkage, C=N units and aromatic rings) and Co sites not only regulate the Li+ coordination environment and rearrange Li+ concentration to facilitate its transport by optimizing the electronic density, enhancing the compatibility with electrolyte interface and supplying “external magnetic driving strategy”, but also strengthens the interfacial stiffness with high Young's modulus to better withstand the mechanical stress. These beneficial effects and relative underlying working mode and mechanism of uniform Li plating and rapid Li+ migration on the Co‐spc‐COP are also revealed by various in situ/ex situ experimental technologies and theory calculation. The Co‐spc‐COP‐based cell delivers an extraordinary lifespan of 6600 h and ultrahigh capacity retention of 78.3 % (111.9 mAh g−1) after 1000 cycles at 1 C. This demonstrated synergistic strategy in Co‐coordinated organic polymer may gain new insights to regulate the uniform and non‐dendritic deposition/dissolution behaviors for highly stable LMBs.