bluuebunny/crossref_metadata_2025 huggingface dataset:
Three dimensionally printed nitrocellulose-based microfluidic platform for investigating the effect of oxygen gradient on cells
Authors: Liu Ping , Fu Longwen , Song Zhihua , Man Mingsan , Yuan Huamao , Zheng Xiaoli , Kang Qi , Shen Dazhong , Song Jinming , Li Bowei , Chen Lingxin
Published: July 2021

The hybrid 3D printed/nitrocellulose-based microfluidic platform analyzed the effect of oxygen gradient on cells with a variety of methods.
Members of the Legionella pneumophila Sde family target tyrosine residues for phosphoribosyl-linked ubiquitination
Authors: Zhang Mengyun , McEwen Joseph M. , Sjoblom Nicole M. , Kotewicz Kristin M. , Isberg Ralph R. , Scheck Rebecca A.
Published: July 2021

During infection, Legionella pneumophila translocates hundreds of effectors into host cells. Among these, the Sde family effector SdeC catalyzes atypical ubiquitination of host targets at tyrosine, not only serine, residues.
Artificial plant cell walls as multi-catalyst systems for enzymatic cooperative asymmetric catalysis in non-aqueous media
Authors: Deiana Luca , Rafi Abdolrahim A. , Naidu Veluru Ramesh , Tai Cheuk-Wai , Bäckvall Jan-E. , Córdova Armando
Published: July 2021

Immobilization of lipase and palladium nanoparticles onto cellulose creates an artificial plant cell wall structure for dynamic kinetic resolution.
Electrochemical phenothiazination of naphthylamines and its application in photocatalysis
Authors: Chen Song , Li Ya-Nan , Xiang Shao-Hua , Li Shaoyu , Tan Bin
Published: July 2021

Chemo- and site-controlled cross-dehydrogenative-coupling of 2-naphthylamines and phenothiazines (phenoxazines) by means of an electrochemical tool has been established to afford PTH type photocatalysts with abundant structural diversity.
Photoinduced transition-metal and external photosensitizer free cross-coupling of aryl triflates with trialkyl phosphites
Authors: Dou Qian , Geng Li , Cheng Bin , Li Chao-Jun , Zeng Huiying
Published: July 2021

Photoinduced phosphonation of aryl triflates with trialkyl phosphites via a tandem single-electron-transfer, C–O bond cleavage and Arbuzov rearrangement process in the absence of transition-metal and external photosensitizer is reported.
Template-free multiple signal amplification for highly sensitive detection of cancer cell-derived exosomes
Authors: Wang Lei , Deng Ying , Huang Yue , Wei Juan , Ma Jiehua , Li Genxi
Published: July 2021

DNase I acted as a bridge to link the DNA-based HCR and TdT-mediated polymerization. The process of DNA-involved signal amplification did not need a label or a complicated nucleic acid sequence design.
Optimized growth and anisotropic properties of Li2ZrTeO6 nonlinear optical crystals
Authors: Guo Xiaojie , Gao Zeliang , Liu Fuan , Du Xiaoli , Wang Xiangmei , Guo Feifei , Li Chengcheng , Sun Youxuan , Tao Xutang
Published: July 2021

Centimeter-sized and high-quality Li2ZrTeO6 crystals were grown by a modified top-seed solution growth method. The excellent thermal properties indicate that Li2ZrTeO6 is an excellent candidate suitable for high-power nonlinear optical applications.
Facile fabrication of hollow CuO nanocubes for enhanced lithium/sodium storage performance
Authors: Zhao Jie , Zhao Yuyan , Yue Wen-Ce , Zheng Shu-Min , Li Xue , Gao Ning , Zhu Ting , Zhang Yu-Jiao , Xia Guang-Ming , Wang Bao
Published: July 2021

Facile and low-toxicity fabrication of CuO hollow nanocubes towards high-performance alkali ion batteries.
Photochromic and photocontrolled luminescent rare-earth D–A hybrid crystals based on rigid viologen acceptors
Authors: Wang Yi-Wen , Li Meng-Hua , Zhang Shu-Quan , Fang Xin , Lin Mei-Jin
Published: July 2021

Due to the introduction of a strong electron donor, CoIII(CN)63−, into the structure, the rare-earth donor–acceptor (D–A) hybrid crystal shows enhanced photochromism. The coordinative Eu3+ cation is also beneficial toward improving the luminescence.
Extending the structural landscape of Mo(vi) hydrazonato inorganic–organic POM-hybrids: an experimental and computational study
Authors: Bebić Nikol , Topić Edi , Mandarić Mirna , Hrenar Tomica , Vrdoljak Višnja
Published: July 2021

Novel Mo(vi) hydrazonato octamolybdate and hexamolybdate hybrids have been synthesized and structurally characterized. Quantum chemical calculations have been applied to determine the possibility of developing the covalently anchored hybrids.
Role of low-energy electrons in the solubility switch of Zn-based oxocluster photoresist for extreme ultraviolet lithography
Authors: Rohdenburg Markus , Thakur Neha , Cartaya René , Castellanos Sonia , Swiderek Petra
Published: July 2021

Electron-induced reactions make an important contribution to the solubility switch of a novel Zn oxocluster resist in extreme ultraviolet lithography (EUVL). The study also gives direct evidence that chain reactions are involved in this process.
Impact of fluorination and chlorination on the electronic structure, topology and in-plane ring normal modes of pyridines
Authors: Benassi Enrico , Vaganova Tamara , Malykhin Evgenij , Fan Haiyan
Published: July 2021

7 halogenated pyridines are investigated through FTIR and Raman spectroscopy and quantum calculations. A rationale on the effects of nature and position of substituents on the ring normal modes’ wavenumbers and other molecular properties is proposed.
Study on the kinetics and dynamics of the H2 + NH2− reaction on a high-level ab initio potential energy surface
Authors: Pan Mengyi , Xiang Haipan , Li Yong , Song Hongwei
Published: July 2021

Dynamics of the two-channel H2 + NH2− reaction on a newly developed PES.
Replacing the cyano (–CN) group to design environmentally friendly fused-ring electron acceptors
Authors: Yao Chuang , Yang Yezi , Li Lei , Bo Maolin , Peng Cheng , Huang Zhongkai , Wang Jinshan
Published: July 2021

A series of electron-withdrawing groups were used to replace –CN to design new environmentally friendly FREAs, and –CHO was found to be the most suitable electron-withdrawing group for constructing high-performance environmentally friendly FREAs.
Thermal crowning mechanism in gold–silica nanocomposites: plasmonic-photonic pairing in archetypal two-dimensional structures
Authors: Utsav  , Khanna Sakshum , Makani Nisha Hiralal , Paneliya Sagar , Mukhopadhyay Indrajit , Banerjee Rupak
Published: July 2021

Thermally driven reconstruction and fabrication of a 2D SERS active substrate.
Chitosan nanocrystals synthesis via aging and application towards alginate hydrogels for sustainable drug release
Authors: Jin Tony , Liu Tracy , Jiang Shuaibing , Kurdyla Davis , Klein Brittney A. , Michaelis Vladimir K. , Lam Edmond , Li Jianyu , Moores Audrey
Published: July 2021

Marine biomass waste is a remarkable source of functional molecules and materials.
Reductive depolymerization as an efficient methodology for the conversion of plastic waste into value-added compounds
Authors: Fernandes Ana C.
Published: July 2021

Reductive depolymerization allows the valorization of polyester, polycarbonate and polyamide waste in a wide variety of value-added compounds with good yields
Plant proteomic research for improvement of food crops under stresses: a review
Authors: Mustafa Ghazala , Komatsu Setsuko
Published: July 2021

Crop improvement approaches have been changed due to technological advancements in traditional plant-breeding methods.
Doping-free bandgap tunability in Fe2O3 nanostructured films
Authors: Kadam Sujit A. , Phan Giang Thi , Pham Duy Van , Patil Ranjit A. , Lai Chien-Chih , Chen Yan-Ruei , Liou Yung , Ma Yuan-Ron
Published: July 2021

Fe2O3 nanostructured films are grown on ITO/glass substrates using the HFMOVD and thermal oxidation techniques. The increase of the Fe2+ cations and cubic (γ) phase leads to a reduction in the bandgap of the Fe2O3 nanostructured films.
Lanthanide upconversion and downshifting luminescence for biomolecules detection
Authors: Sun Guotao , Xie Yao , Sun Lining , Zhang Hongjie
Published: July 2021

In this review article, we focus on recent advances in the detection of biomolecule activities based on lanthanide luminescent systems, including UCNPs, Ln-MOFs, and lanthanide organic complexes.
Inhibition of non-enzymatic glycation by capsaicin: targeting AGE-induced diabetic complications
Authors: Xu Ping , Yang Xiaodong , Wang Yu
Published: July 2021

Capsaicin inhibits the non-enzymatic glycation of human serum albumin.
Synthesis and photophysical properties of 5-(3′′-alkyl/aryl-amino-1′′-azaindolizin-2′′-yl)-2′-deoxyuridines
Authors: Kumar Sandeep , Kumar Sumit , Maity Jyotirmoy , Kumar Banty , Bali Mehta Shilpika , Prasad Ashok K.
Published: July 2021

The Groebke–Blackburn–Bienayame (GBB) reaction has been used for the efficient synthesis of novel fluorescent 5-azaindolizino-2′-deoxyuridines starting from commercially available thymidine following two strategies.
Synthesis of graphene nanoplatelets/polythiophene as a high performance supercapacitor electrode material
Authors: Rahman Ata ur , Noreen Hamsa , Nawaz Zeeshan , Iqbal Javed , Rahman Gul , Yaseen Muhammad
Published: July 2021

The preparation of a stable, efficient, inexpensive and high capacitance electrode material for supercapacitors is posing great challenges for researchers.
Green synthesis of fluorescent Schiff bases: chemo-photophysical characterization, X-ray structures, and their bioimaging
Authors: Xochicale-Santana Leonardo , López-Espejel Margarita , Jiménez-Pérez Víctor M. , Lara-Cerón Jesús , Gómez-Treviño Alberto , Waksman Noemí , Dias H. V. Rasika , Muñoz-Flores Blanca M.
Published: July 2021

Two Schiff bases have been prepared by mechano- and ultrasound-assisted synthesis and their structures were elucidated by X-ray diffraction. One of them showed good fluorescent cell staining in vitro and low cytotoxicity.
Exploiting the photocatalytic activity of TiO2 towards the depolymerization of Kraft lignin
Authors: Crites Charles-Oneil L. , Gomes de Mendonça Fernanda , Netto-Ferreira José Carlos , Baker R. Tom , Hallett-Tapley Geniece L. , Tremblay Luc
Published: July 2021

Lignin is a promising renewable source of aromatic chemicals.
Correction: Furin-instructed molecular self-assembly actuates endoplasmic reticulum stress-mediated apoptosis for cancer therapy
Authors: Fu Chenxing , Zhan Jie , Huai Junqi , Ma Shaodan , Li Minghui , Chen Guoqin , Chen Minsheng , Cai Yanbin , Ou Caiwen
Published: July 2021

Correction for ‘Furin-instructed molecular self-assembly actuates endoplasmic reticulum stress-mediated apoptosis for cancer therapy’ by Chenxing Fu et al., Nanoscale, 2020, 12, 12126–12132, DOI: 10.1039/D0NR00151A.
Self-branched Nb2O5 nanoarrays as “electron-ion reservoirs” to enhance the conversion of polysulfides in flexible Li–S batteries
Authors: Li Huanhuan , Chen Huiqin , Chen Yuxin , Bai Guangyue , Zhang Mengjie , Xie Shanshan , Zhuo Kelei
Published: July 2021

A novel sulfur matrix integrating self-branched Nb2O5 nanoarrays and flexible carbon cloth (NBCC) is designed. Intriguingly, the selected Nb2O5 nanoarrays can work as “electron-ion reservoirs” to accelerate the conversion reaction of LiPSs.
Deriving physical parameters of unresolved star clusters
Authors: Naujalis Rokas , Stonkutė Rima , Vansevičius Vladas
Published: July 2021

Context. This study is the sixth of a series that investigates degeneracy and stochasticity problems present in the determination of the age, mass, extinction, and metallicity of partially resolved or unresolved star clusters in external galaxies when using Hubble Space Telescope broadband photometry. In the fifth publication, it was noticed that inconsistencies in cluster colour indices, which arise due to projected foreground and background stars on the apertures, enhance age-metallicity-extinction degeneracies.

Aims. In this work we aim to present new aperture photometry results for a sample of star clusters from the M 31 Panchromatic Hubble Andromeda Treasury (PHAT) survey.

Methods. We employed two methods of aperture photometry. The first method is ordinary aperture photometry to measure total cluster fluxes. The second method was introduced to avoid the brightest foreground and background stars that project onto large apertures. This method employs smaller apertures, adapted to cover a central part of clusters, and applies an aperture correction, derived for the F475W passband, to other passbands. We note that this procedure is valid only for clusters without prominent systematic gradients of colour indices beyond half-light radii.

Results. We present two catalogues of star cluster aperture photometry (produced by applying ordinary aperture photometry and adaptive aperture photometry methods) with estimated uncertainties for a sample of 1181 star clusters from the M 31 PHAT survey. Compared to the M 31 PHAT fundamental star cluster aperture photometry catalogue published by Johnson et al., there are changes made in the following: cluster centre coordinates, aperture sizes, and sky background estimates.
MeerKAT 21-cm H I imaging of Abell 2626 and beyond
Authors: Healy J. , Deb T. , Verheijen M. A. W. , Blyth S.-L. , Serra P. , Ramatsoku M. , Vulcani B.
Published: July 2021

Context. The morphology-density relation manifests the environmental dependence of the formation and evolution of galaxies as they continuously migrate through the cosmic web to ever denser environments. As gas-rich galaxies traverse the outskirts and inner regions of galaxy clusters, they experience sudden and radical changes in their gas content and star formation activity.

Aims. The goal of this work is to gain an H I perspective on gas depletion mechanisms acting on galaxies and galaxy groups that are being accreted by a moderately massive galaxy cluster. We aim to study the relative importance and efficiency of processes such as ram-pressure stripping and tidal interactions as well as their dependency on the local and global environment of galaxies in the cluster core and in its surroundings.

Methods. We have conducted a blind radio continuum and H I spectral line imaging survey with the MeerKAT radio telescope of a 2° × 2° area centred on the galaxy cluster Abell 2626. We have used the CARAcal pipeline to reduce the data, SoFiA to detect sources within the H I data cube, and GIPSY to construct spatially resolved information on the H I morphologies and kinematics of the H I detected galaxies.

Results. We have detected H I in 219 galaxies with optical counterparts within the entire surveyed volume. We present the H I properties of each of the detected galaxies as a data catalogue and as an atlas page for each galaxy, including H I column-density maps, velocity fields, position-velocity diagrams, and global H I profiles. These data will also be used for case studies of identified ‘jellyfish’ galaxies and galaxy population studies by means of morphological classification of the direct H I detections as well as using the H I stacking technique.
Liquid Biopsy beim Mammakarzinom
Authors: Banys-Paluchowski Maggie , Krawczyk Natalia , Fehm Tanja
Published: July 2021

In den letzten Jahren gewinnt die Liquid Biopsy, d. h. die blutbasierte Untersuchung von zirkulierenden Tumorzellen (CTCs) und Nukleinsäuren (DNA/RNA) beim Mammakarzinom zunehmend an Relevanz. Zahlreiche Studien haben bereits die hohe prognostische Bedeutung der CTC-Detektion sowohl im frühen als auch metastasierten Stadium gezeigt. Des Weiteren korrelieren die Veränderungen der CTC-Zahlen und der zirkulierenden Tumor-DNA (ctDNA) im Verlauf der Erkrankung mit dem Ansprechen auf die Therapie. Im Fokus der Forschung stehen derzeit die Liquid-Biopsy-basierten Therapieinterventionen beim metastasierten Mammakarzinom. In diesem Kontext wurde Alpelisib, ein PI3K-Inhibitor, als erste Substanz durch die FDA und die EMA zugelassen.
Structured Reporting of Acute Ischemic Stroke – Consensus-Based Reporting Templates for Non-Contrast Cranial Computed Tomography, CT Angiography, and CT Perfusion
Authors: Brendle Cornelia , Bender Benjamin , Selo Nadja , Poli Sven , Tünnerhoff Johannes , Huber Thomas , Kirschke Jan , Boeckh-Behrens Tobias , Pinto dos Santos Daniel , Wiest Roland , Berlis Ansgar , Liebig Thomas , Korczynski Oliver , Ernemann Ulrike , Hempel Johann-Martin
Published: July 2021

Purpose Structured reporting is an essential step in establishing standardized quality standards in diagnostic radiology. The German Society of Radiology and the German Society of Neuroradiology aim to provide templates for the structured reporting of different radiological examinations.

Method The Information Technology working group of the German Society of Radiology developed structured templates for the radiological reporting of different indications in consensus with specialist support by experts.

Results We present a template for the structured reporting of examinations of patients with acute ischemic stroke by non-contrast computed tomography, CT angiography, and CT perfusion. This template is provided on the website www.befundung.drg.de for free use.

Conclusion Implementation of the structured template may increase quality and provide a minimum standard for radiological reports in patients with acute ischemic stroke.

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Citation Format
Tick tock goes the mercury trapped ion clock
Authors: Bandari Anashe
Published: July 2021

Only 30 cubic centimeters in size, the physics package of the micro mercury trapped ion clock is one of the smallest, and the most precise and stable to date.
CMOS transistors functioning at cryogenic temperatures point to potential capacitorless memory
Authors: Liebendorfer Adam
Published: July 2021

Sharp current jumps and stable hysteretic loops in the drain current as a function of gate voltage lead to effective back-gating of the inversion channel.
Global well-posedness for the cubic nonlinear Schrödinger equation with initial data lying in L
p-based Sobolev spaces
Authors: Dodson Benjamin , Soffer Avraham , Spencer Thomas
Published: July 2021

In this paper, we continue our study [B. Dodson, A. Soffer, and T. Spencer, J. Stat. Phys. 180, 910 (2020)] of the nonlinear Schrödinger equation (NLS) with bounded initial data which do not vanish at infinity. Local well-posedness on R was proved for real analytic data. Here, we prove global well-posedness for the 1D NLS with initial data lying in Lp for any 2 < p < ∞, provided that the initial data are sufficiently smooth. We do not use the complete integrability of the cubic NLS.
Low frequency topologically protected wave transport in sinusoidal lightweight acoustic metamaterials
Authors: Chen Zhenyu , Muhammad  , Wang Xiangyu , Lim C. W.
Published: July 2021

Topological phononic crystals and acoustic metamaterials have attracted enormous research attention in recent years due to the presence of robust and disorder-immune wave propagation. In this study, a sinusoidal lightweight elastic topological insulator with protected interface modes is investigated at a subwavelength frequency region. By a wave dispersion study, the dual Dirac cones are observed at a subwavelength frequency region due to the employment of two distinct cylinders connected with sinusoidal ligaments. Both cylindrical masses and sinusoidal ligaments are found responsible for opening low-frequency bandgaps that manipulate elastic wave wavelengths almost 30 times larger than the lattice size. Consequently, the subwavelength bandgap closing-and-reopening phenomenon with phase transitions is further captured and opposite signs of the valley Chern numbers are obtained for different structural parameters. A supercell structure is constructed based on the phase transition, and dual topologically protected interface modes (TPIMs) are captured with different quality factors. The comparison of topologically protected interface modes shows that TPIM I is in a higher and wider frequency range, while TPIM II is positioned in a comparatively narrow and extremely low-frequency range. Finally, the robust elastic wave propagation along various designated paths is demonstrated. The proposed lightweight topologically protected phononic lattice may spark future investigation of topological edge states in metadevices at a subwavelength frequency region.
A deep learning approach for trustworthy high-fidelity computational holographic orbital angular momentum communication
Authors: Zhou Hongqiang , Wang Yongtian , Li Xin , Xu Zhentao , Li Xiaowei , Huang Lingling
Published: July 2021

Orbital angular momentum (OAM) holography is becoming a promising technology for image encryption, optical transmission, and storage because of its excellent fidelity, orthogonality, and security. Benefiting from the powerful ability of machine learning to learn from big data features, a computational holographic orbital angular momentum (OAM) communication method using OAM hologram encoding and machine learning decoding is proposed. The OAM information representing the grayscale of the images is encoded into different holograms. Subsequently, using a well-trained convolutional neural network, the holograms carrying arbitrary image information can be accurately transmitted and translated, and the hidden OAM information is readout quickly and accurately as an added confidential channel. Topological charge digits can be arranged to form grayscale images or serial codes. Such a computational holographic OAM communication method can be used for extended channels with high security and complexity. In addition, this method can be applied in areas of confidential digital modulation/demodulation and encrypted communication, as well as expand the transmission capacity.
A comprehensive computational and principal component analysis on various choline chloride-based deep eutectic solvents to reveal their structural and spectroscopic properties
Authors: Rain Mahmudul Islam , Iqbal Humayun , Saha Mousumi , Ali Md Ackas , Chohan Harmeet Kaur , Rahman Md Sajjadur , Halim Mohammad A.
Published: July 2021

In this study, the quantum chemical properties, nonbonding interactions, and spectroscopic insights of a wide variety of choline chloride (ChCl)-based deep eutectic solvents were investigated employing molecular dynamics (MD), density functional theory, and spectroscopic analyses. Nine experimentally reported ChCl-based deep eutectic solvents (DESs) were selected for this study where ChCl was common in all the DESs and the hydrogen bond donors (HBDs) were varied. The most energetically favorable cluster was selected using MD simulation followed by density functional theory calculation. The most stable cluster structures were fully optimized, and their quantum chemical properties and IR spectra were computed at the ωB97XD/6-31G++(d,p) level of theory. Principal component analysis was performed to distinguish their behavioral differences and to find out if any correlation exists among the 1:1 and 1:2 clusters. The atom–atom radial distribution functions based on MD simulations revealed that several hydrogen bonds were formed among the donor and acceptor molecules. However, the most prominent hydrogen bonds were found to be N–HHBD⋯Cl− for ChCl:U, ChCl:TU, and ChCl:Ace and O–HHBD⋯Cl− for ChCl:Glu, ChCl:Ma, ChCl:Ox, ChCl:Gly, and ChCl:Phe. Both N–HHBD⋯Cl− and O–HHBD⋯Cl− were major interactions for ChCl:Pro, where Cl− worked as a bridge between Ch+ and the respective donors. In addition, the –OH of Ch+ showed strong intermolecular interactions with the acceptor groups of the donor molecules, such as C=O and O–H. This study has tried to extract a pattern of the contributions of HBDs by comparing the structural, spectroscopic, and thermodynamic properties of ChCl-based DESs, which have also been successfully correlated with the intermolecular interactions.
A fresh look at the structure of aromatic thiols on Au surfaces from theory and experiment
Authors: Hekele Joscha , Linke Matthias , Keller Thomas , Jose Jesil , Hille Marvin , Hasselbrink Eckart , Schlücker Sebastian , Kratzer Peter
Published: July 2021

A detailed study of the adsorption structure of self-assembled monolayers of 4-nitrothiophenol on the Au(111) surface was performed from a theoretical perspective via first-principles density functional theory calculations and experimentally by Raman and vibrational sum frequency spectroscopy (vSFS) with an emphasis on the molecular orientation. Simulations—including an explicit van der Waals (vdW) description—for different adsorbate structures, namely, for (3×3), (2 × 2), and (3 × 3) surface unit cells, reveal a significant tilting of the molecules toward the surface with decreasing coverage from 75° down to 32° tilt angle. vSFS suggests a tilt angle of 50°, which agrees well with the one calculated for a structure with a coverage of 0.25. Furthermore, calculated vibrational eigenvectors and spectra allowed us to identify characteristic in-plane (NO2 scissoring) and out-of-plane (C–H wagging) modes and to predict their strength in the spectrum in dependence of the adsorption geometry. We additionally performed calculations for biphenylthiol and terphenylthiol to assess the impact of multiple aromatic rings and found that vdW interactions are significantly increasing with this number, as evidenced by the absorption energy and the molecule adopting a more upright-standing geometry.
Hysteretic mutual phase-locking of perpendicular-to-plane polarizer spin-torque nano-oscillator pairs analyzed by a generalized pendulum-like model
Authors: Chen Hao-Hsuan , Lee Ching-Ming , Zeng Lang , Zhao Wei-Sheng , Chang Ching-Ray
Published: July 2021

At present, the Kuramoto model is the standard and widely accepted theoretical approach for analyzing the synchronization of spin-torque nano-oscillators (STNOs) coupled by an interaction. Nevertheless, the oscillatory decaying regime and the initial condition (IC)-dependence (hysteretic) that exist in the synchronization of many types of STNOs cannot be explained by this model. In order to more precisely elucidate the physical mechanisms behind the two phenomena, in this paper we develop a generalized pendulum-like model based on the two common features of non-linear auto-oscillators: one is the stability of the amplitude/energy of dynamic states and the other is the non-linear dynamic state energy of oscillators. In this new model, we find that the Newtonian-like particle with sufficient kinetic energy can overcome the barrier of phase-locking potential to evolve into a stable asynchronization state, leading to the IC-dependent synchronization. Furthermore, due to the presence of kinetic energy, this particle can also oscillate around the minima of the phase-locking potential, leading to the oscillatory decaying regime. Thereby, in this work, we adopt this new model to analyze the IC-dependent mutual synchronization of perpendicular-to-plane-STNO pairs, and then we suggest that the initial conditions can be controlled to avoid such a phenomenon by using magnetic dipolar coupling.
Mechanical and dynamic stability of ZnX chalcogenide (X=O, S, Se, Te) monolayers and their electronic, optical, and thermoelectric properties
Authors: Monteiro J. R. M. , Mota Cicero , Gusmão M. S. S. , Ghosh Angsula , Frota H. O.
Published: July 2021

Graphene-like ZnX (X=O, S, Se, Te) structures are studied using the DFT+U method to address in detail the questions regarding the dynamical stability and also their utility in optoelectronic devices. The layer modulus, the Young's modulus, the shear modulus, and the Poisson coefficient demonstrate the stability of all ZnX in the presence of the Hubbard parameter U. Cohesion energy calculations show ZnO to be the most stable one and ZnSe to be the least stable one among the four systems. The presence of a direct bandgap in all the systems makes them suitable for use in optoelectronic devices. The gap values range between 2.13 eV in ZnTe and 3.50 eV in ZnO. U values tend to increase the bandgap in all the systems. This increase is seen to be as high as 100% in ZnO. A detailed study of the band structure and partial density of states is carried out. The electronic, optical, and thermoelectric properties of the ZnX monolayers are exhibited. The superior limit of the figure of merit increases with temperature and the highest value is found to be of the order of 0.6 in ZnO at 900 °C. Overall, the inclusion of the Hubbard parameter demonstrates better stability and also its importance in technological applications.
Phonon–dislocation interaction and its impact on thermal conductivity
Authors: Cheng Yajuan , Nomura Masahiro , Volz Sebastian , Xiong Shiyun
Published: July 2021

This Perspective describes the phonon transport engineering with one-dimensional defects, i.e., dislocations, from both theoretical and experimental points of view. The classical models, modern atomistic simulations, and advanced experimental investigations on thermal conductivity reduction by dislocations are discussed. Particularly, the complex stress field induced by dislocations, the phonon–dislocation interaction mechanisms, and the anisotropic thermal transport in materials with well-oriented dislocations are emphasized. Further investigations of phonon–dislocation interactions in both theory and experiments are prospected at the end of the work.
A theory of localized excitations in supercooled liquids
Authors: Hasyim Muhammad R. , Mandadapu Kranthi K.
Published: July 2021

A new connection between the structure and dynamics in glass-forming liquids is presented. We show how the origin of spatially localized excitations, as defined by the dynamical facilitation (DF) theory, can be understood from a structure-based framework. This framework is constructed by associating excitation events in the DF theory to hopping events between energy minima in the potential energy landscape (PEL). By reducing the PEL to an equal energy well picture and applying a harmonic approximation, we develop a field theory to describe elastic fluctuations about inherent states, which are energy minimizing configurations of the PEL. We model an excitation as a shear transformation zone (STZ) inducing a localized pure shear deformation onto an inherent state. We connect STZs to T1 transition events that break the elastic bonds holding the local structure of an inherent state. A formula for the excitation energy barrier, denoted as Jσ, is obtained as a function of inherent-state elastic moduli and the radial distribution function. The energy barrier from the current theory is compared to the one predicted by the DF theory where good agreement is found in various two-dimensional continuous poly-disperse atomistic models of glass formers. These results strengthen the role of structure and elasticity in driving glassy dynamics through the creation and relaxation of localized excitations.
Direct observation of resonant tunneling in heterostructure with a single quantum well
Authors: Zubkov V. I. , Ivanova Iana V. , Weyers M.
Published: July 2021

A resonant-tunneling conductivity was experimentally registered in a doped heterostructure with a single quantum well using admittance spectroscopy. Earlier, this effect was only realized in artificially created resonant tunneling structures, having four heterojunctions. A heterostructure with an In0.3Ga0.7As/GaAs quantum well was examined in the temperature range of 10–300 K. In admittance spectra, a competition of thermionic and tunneling escape mechanisms was noticed with a non-exponential Arrhenius plot. By means of numerical self-consistent simulations in a quantum box, we have shown the role of a quasi-bound level in resonant tunneling of electrons; in addition, the energies and wave functions of the quasi-bound state were derived in dependence on an applied bias. The modification of a transparency coefficient for a two-barrier Hartree potential as a function of the quantum well width and in dependence on the applied bias was also calculated. The resonant state took place only at symmetric barriers and disappeared, when the electric field tilted the barriers. The results can be used to develop a new type of resonant tunneling diodes and as a method for diagnostics of the tunnel effect in semiconductors.
Chimera states and frequency clustering in systems of coupled inner-ear hair cells
Authors: Faber Justin , Bozovic Dolores
Published: July 2021

Coupled hair cells of the auditory and vestibular systems perform the crucial task of converting the energy of sound waves and ground-borne vibrations into ionic currents. We mechanically couple groups of living, active hair cells with artificial membranes, thus mimicking in vitro the coupled dynamical system. We identify chimera states and frequency clustering in the dynamics of these coupled nonlinear, autonomous oscillators. We find that these dynamical states can be reproduced by our numerical model with heterogeneity of the parameters. Furthermore, we find that this model is most sensitive to external signals when poised at the onset of synchronization, where chimera and cluster states are likely to form. We, therefore, propose that the partial synchronization in our experimental system is a manifestation of a system poised at the verge of synchronization with optimal sensitivity.
Self-consistent density-based basis-set correction: How much do we lower total energies and improve dipole moments?
Authors: Giner Emmanuel , Traore Diata , Pradines Barthélemy , Toulouse Julien
Published: July 2021

This work provides a self-consistent extension of the recently proposed density-based basis-set correction method for wave function electronic-structure calculations [E. Giner et al., J. Chem. Phys. 149, 194301 (2018)]. In contrast to the previously used approximation where the basis-set correction density functional was a posteriori added to the energy from a wave-function calculation, here the energy minimization is performed including the basis-set correction. Compared to the non-self-consistent approximation, this allows one to lower the total energy and change the wave function under the effect of the basis-set correction. This work addresses two main questions: (i) What is the change in total energy compared to the non-self-consistent approximation and (ii) can we obtain better properties, namely, dipole moments, with the basis-set corrected wave functions. We implement the present formalism with two different basis-set correction functionals and test it on different molecular systems. The main results of the study are that (i) the total energy lowering obtained by the self-consistent approach is extremely small, which justifies the use of the non-self-consistent approximation, and (ii) the dipole moments obtained from the basis-set corrected wave functions are improved, being already close to their complete basis-set values with triple-zeta basis sets. Thus, the present study further confirms the soundness of the density-based basis-set correction scheme.
Development of magnetic responsive random lasers fabricated by a laser-induced surface roughness
Authors: Fujiwara Hideki , Kawaguchi Shohei , Yonekawa Daiki , Kaiju Hideo
Published: July 2021

A magnetic responsive random laser was developed by roughening the surface of a NiFe alloy thin film-coated GaN substrate using an intense laser. By dispersing the magnetic materials and fabricating a surface roughness on the GaN surface after irradiation with intense laser pulses, we confirmed that the threshold of the random laser can be changed by applying an external magnetic field on the substrate. This result suggests that the magneto-optical effect of the residual NiFe alloy on the surface changes the local random feedback, leading to a change in the lasing behavior. Thus, we developed a simple method to fabricate a magnetically responsive random laser directly on a semiconductor substrate using only short laser irradiation.
Expanding the scope of antenna–reactor photocatalysts for strong visible light absorption in small transition metal nanoparticles
Authors: Huang Ye , Chen Yun , Deng Liren , Zhu Yukun , Huang Yu
Published: July 2021

The design of antenna–reactor photocatalysts has become a powerful strategy to covert transition metal reactors from traditional thermocatalysts to novel photocatalysts. Plasmonic metals are often used as the optical antenna. Here, we demonstrate that conventional dielectric supports with high refractive index are able to achieve comparable performance as the plasmonic antennas, giving rise to a huge enhancement of the visible light absorption in the small Pt nanoparticles (NPs) of the core–satellite antenna–reactor photocatalysts through resonance energy transfer. The absorption enhancement can be mediated not only by the electric resonances of the plasmonic antenna but also by the magnetic resonances of the dielectric antenna. A large enough dielectric antenna or a small plasmonic antenna is desired for the generation of strong optical resonances. Judged by those Pt NPs with strong visible light absorption enhancement, the potential catalytically active sites are mainly distributed at the back side of the dielectric antenna, while they may be widely distributed over the surface of the plasmonic antenna with probably lower activities. The expanding scope of antenna–reactor photocatalysts offers new opportunities for solar to chemical energy conversion using nonplasmonic catalytic transition metals.
Thermal stability of crown-motif [Au9(PPh3)8]3+ and [MAu8(PPh3)8]2+ (M = Pd, Pt) clusters: Effects of gas composition, single-atom doping, and counter anions
Authors: Matsuyama Tomoki , Kikkawa Soichi , Fujiki Yu , Tsukada Mio , Takaya Hikaru , Yasuda Nobuhiro , Nitta Kiyofumi , Nakatani Naoki , Negishi Yuichi , Yamazoe Seiji
Published: July 2021

The thermal behaviors of ligand-protected metal clusters, [Au9(PPh3)8]3+ and [MAu8(PPh3)8]2+ (M = Pd, Pt) with a crown-motif structure, were investigated to determine the effects of the gas composition, single-atom doping, and counter anions on the thermal stability of these clusters. We successfully synthesized crown-motif [PdAu8(PPh3)8][HPMo12O40] (PdAu8–PMo12) and [PtAu8(PPh3)8][HPMo12O40] (PtAu8–PMo12) salts with a cesium-chloride-type structure, which is the same as the [Au9(PPh3)8][PMo12O40] (Au9–PMo12) structure. Thermogravimetry-differential thermal analysis/mass spectrometry analysis revealed that the crown-motif structure of Au9–PMo12 was decomposed at ∼475 K without weight loss to form Au nanoparticles. After structural decomposition, the ligands were desorbed from the sample. The ligand desorption temperature of Au9–PMo12 increased under 20% O2 conditions because of the formation of Au nanoparticles and stronger interaction of the formed O=PPh3 than PPh3. The Pd and Pt single-atom doping improved the thermal stability of the clusters. This improvement was due to the formation of a large bonding index of M–Au and a change in Au–PPh3 bonding energy by heteroatom doping. Moreover, we found that the ligand desorption temperatures were also affected by the type of counter anions, whose charge and size influence the localized Coulomb interaction and cluster packing between the cationic ligand-protected metal clusters and counter anions.
Using automated serendipity to discover how trace water promotes and inhibits lead halide perovskite crystal formation
Authors: Nega Philip W. , Li Zhi , Ghosh Victor , Thapa Janak , Sun Shijing , Hartono Noor Titan Putri , Nellikkal Mansoor Ani Najeeb , Norquist Alexander J. , Buonassisi Tonio , Chan Emory M. , Schrier Joshua
Published: July 2021

Halide perovskite materials have attracted great interest for applications in low-cost, solution-processed solar cells and other optoelectronics applications. The role of moisture in perovskite device degradation and crystal formation processes remains poorly understood. Here, we use a data-driven approach to discover the influence of trace amounts of water on perovskite crystal formation by analyzing a comprehensive dataset of 8470 inverse-temperature crystallization lead iodide perovskite synthesis reactions, performed over 20 months using a robotic system. We identified discrepancies between the empirical crystal formation rates in batches of experiments conducted under different ambient relative humidity conditions for each organoammonium cation. We prioritized these using a statistical model and then used the robotic system to conduct 1296 controlled interventional experiments, in which small amounts of water were deliberately introduced to the reactions. The addition of trace amounts of water promotes crystal formation for 4-methoxyphenylammonium lead iodide and iso-propylammonium lead iodide and inhibits crystal formation for dimethylammonium lead iodide and acetamidinium lead iodide. We also performed thin-film syntheses of these four materials and determined the grain size distributions using scanning electron microscopy. The addition of water results in smaller grain sizes for dimethylammonium and larger grain sizes for iso-propylammonium, consistent with earlier or delayed nucleation, respectively. The agreement between the inverse temperature crystallization and thin film results indicates that this is a feature of the organoammonium-water interaction that persists despite differences in the synthesis method.
High-mobility amorphous PTB7 organic transistors enabled by high-capacitance electrolyte dielectric
Authors: Nketia-Yawson Benjamin , Lee Ji Hyeon , Jo Jea Woong
Published: July 2021

Molecular engineering of organic semiconductors through different synthetic routes has remarkably improved the understanding of the structure–property relationship and charge transport physics, particularly in organic field-effect transistors (OFETs). Emerging OFETs with reliable charge-carrier mobilities exceeding >1 cm2 V−1 s−1 have been demonstrated. However, the field-effect mobilities of amorphous conjugated polymer semiconductors have still showed the values below 10−2 cm2 V−1 s−1 over the past two decades. Here, we report on highly reproducible amorphous organic PTB7 transistors with an exceptional mobility of 0.80 cm2 V−1 s−1 (μavg ≈ 0.51 ± 0.16 cm2 V−1 s−1) operating at 2 V comparable to that of inorganic amorphous silicon semiconductor devices (0.5–1 cm2 V−1 s−1). This remarkable performance is enabled by the use of high-capacitance electrolyte dielectric (Ci = 48.42 μF cm−2), allowing easily attainable lower contact resistance of < 400 Ω cm and improved charge carrier density in the transistor channel, compared to those fabricated using low-k poly(methyl methacrylate) (Ci = 6.2 nF cm−2) and high-k poly(vinylidene fluoride-co-hexafluoropropylene) (Ci = 49.8 nF cm−2) gate dielectrics. This work contributes an opportunity for understanding and improving device performances of amorphous conjugated polymer semiconductors.
Properties of orthorhombic Ga2O3 alloyed with In2O3 and Al2O3
Authors: Seacat Sierra , Lyons John L. , Peelaers Hartwin
Published: July 2021

Ga2O3 is a promising wide-bandgap material for electronic applications. The metastable orthorhombic κ phase is of particular interest due to its large predicted spontaneous electrical polarization. Here, we investigate how the properties of the orthorhombic phase can be tuned by alloying with In2O3. In particular, we determine how the lattice constants, bandgap, and band offsets change over the full range of possible alloy compositions. For completeness, we also compare to alloys with Al2O3. Lattice constants decrease linearly with Al content, while the bandgaps and conduction-band offsets increase non-linearly, with a bowing of 1.41 eV. Alloying with In2O3 allows to increase the lattice constants linearly and to decrease the bandgaps and conduction-band offsets non-linearly, with a bowing of 0.31 eV. Alloying, therefore, allows for the modification of the structural and electronic properties over a wide range, opening the possibility to tailor the alloy properties to specific applications.
Bypass fat enhances liveweight gain and meat quality but not profitability of smallholder cattle fattening systems based on oil palm frond
Authors: Pimpa O. , Binsulong B. , Pastsart U. , Pimpa B. , Liang J. B.
Published: July 2021

Context Oil palm frond (OPF) is abundantly available throughout Southeast Asia and is a good source of forage for feedlot cattle, particularly during the dry and monsoon seasons when other forage options are limited. However, the use of OPF in ruminants feed is constrained by its complex fibrous structure and low digestibility. Aims The aim of this study was to investigate the impact of supplementation with bypass fat on growth, meat quality and economic returns in smallholder feedlot systems where Napier grass is replaced with OPF. Methods Sixteen Brahman × Charolais crossbred steers, 23 ± 2.0 months old and with initial bodyweight of 425 ± 59.9 kg (mean ± s.e.), were randomly allocated in a 2 × 2 factorial randomised complete-block design experiment with the following dietary treatments: (i) fresh chopped Napier grass-based total mixed ration (TMR; Napier grass–fat), (ii) Napier grass-based TMR + 5% bypass fat (Napier grass+fat), (iii) OPF-based TMR (OPF–fat) and (iv) OPF-based TMR + 5% bypass fat (OPF+fat). Feed intake, digestibility of the diets and average daily gain were measured. The cattle were slaughtered to determine carcass dressing percentage and meat quality. Costs and return of fattening cattle were estimated. Key results Despite higher intake, cattle fed OPF–fat had a lower bodyweight gain than did cattle fed grass-based diets due to lower digestibility. Bypass-fat supplementation increased the bodyweigh of cattle fed OPF but not of cattle fed Napier grass. Fat supplementation enhanced colour, backfat thickness, and fat content of meat in both the Napier grass- and OPF-based diets. However, replacing Napier grass with OPF reduced the net profit of smallholder feedlot systems, even with fat supplementation. Conclusion While fat supplementation increased liveweight gain and enhanced some aspects of meat quality, the increased feeding cost reduced net profit. Therefore, supplementation of OPF with bypass fat is not recommended for smallholder feedlots in developing countries. Implications Appropriate technology to reduce the feeding cost of OPF needs to be developed to make it an economically viable option for smallholder farmers.
Plasticisers in the terrestrial environment: sources, occurrence and fate
Authors: Billings Alex , Jones Kevin C. , Pereira M. Glória , Spurgeon David J.
Published: July 2021

Environmental context Many human activities cause the release of plastic and associated plasticisers to land, where chemicals may persist for extended periods and be taken up by organisms. However, quantitative information of the terrestrial occurrence, fate and exposure of phthalate and non-phthalate plasticisers is lacking. Research into this field is needed, especially as society moves away from phthalates to the next generation of plasticisers which may themselves represent an emerging risk. Abstract Modern society is widely dependent upon plastic. Therefore, it is unsurprising that macro- and microplastic pollution is found in every environmental compartment on earth. Plasticisers are chemicals added to plastics to increase their flexibility. Like plastics themselves, plasticisers are also widely present in the environment. Plasticisers and plastic debris may undergo long-range transport in the atmosphere and the oceans, contaminating even the most remote areas of land. In addition, although plasticisers typically degrade in a matter of weeks–months, they can persist in soil for decades and have been shown to occur in all land uses studied. Some plasticisers are genotoxic and can be taken up by soil organisms, which may pose a risk to ecosystems and human health. To date the majority of data on plasticisers exists for phthalates. However, plasticisers are a diverse range of chemicals and with the increasing transfer to non-phthalate alternatives, research into the fate and effects of emerging plasticisers is required to determine their environmental risk and management options. Data on the occurrence and ecotoxicity of emerging plasticisers, in addition to the impacts of all plasticisers on terrestrial ecosystems, therefore, remain a key research need within the wider plastics debate.