bluuebunny/crossref_metadata_2025 huggingface dataset:
Amphiphilic titania Janus nanoparticles containing ionic groups prepared in oil–water Pickering emulsion
Authors: Niedner Lucas , Kickelbick Guido
Published: February 2024

We established a simple one-step Pickering emulsion approach to prepare amphiphilic cationic titania Janus particles for the self-assembly at solid–liquid and liquid–liquid interfaces.
Enhanced linear and symmetric synaptic weight update characteristics in a Pt/p-LiCoOx/p-NiO/Pt memristor through interface energy barrier modulation by Li ion redistribution
Authors: Jeong Boyoung , Chung Peter Hayoung , Han Jimin , Noh Taeyun , Yoon Tae-Sik
Published: February 2024

A memristor with a Pt/p-LiCoOx/p-NiO/Pt structure exhibited enhanced linear and symmetric conductance changes for synaptic weight update, which was driven by interface energy barrier modulation as a result of Li ion redistribution.
Enhanced rate of sarcosine N-carboxyanhydride polymerisation from a lysine dendrimer macroinitiator driven by neighbouring H-bonding effects
Authors: England Richard M. , Yu Qing , Westley Chloe , Mallia Carl J. , Treacher Kevin E. , Norrby Per-Ola , Ashford Marianne B.
Published: February 2024

In situ FTIR monitoring revealed that sarcosine N-carboxyanhydride polymerisations were catalysed using a lysine dendrimer macroinitiator owing to hydrogen bonding interactions between the dendrimer core and monomer.
Quasi-spherical silver nanoparticles for human prolactin detection by surface-enhanced Raman spectroscopy
Authors: Ortiz-Dosal Alejandra , Rodríguez-Aranda M. C. , Ortiz-Dosal Luis Carlos , Núñez-Leyva Juan Manuel , Rivera-Pérez Emmanuel , Cuellar Camacho José Luis , Ávila-Delgadillo Julián Rosendo , Kolosovas-Machuca Eleazar Samuel
Published: February 2024

In this paper, we determined the Raman and SERS spectrum of human prolactin at physiological concentration using a colloidal solution of AgNPs.
Alkyl chain functionalised Ir(iii) complexes: synthesis, properties and behaviour as emissive dopants in microemulsions
Authors: Stokes Emily C. , Shoetan Ibrahim O. , Gillman Alice M. , Horton Peter N. , Coles Simon J. , Woodbury Simon E. , Fallis Ian A. , Pope Simon J. A.
Published: February 2024

Luminescent, alkyl chain functionalised Ir(iii) complexes have been synthesised, characterised and studied in microemulsion environments showing retention of emissive behaviour.
Ball milling synthesis of Fe3O4 nanoparticles-functionalized porous boron nitride with enhanced cationic dye removal performance
Authors: Li Jie , Wang Chuanhui , Chen Xinqi , Ma Yunxiu , Dai Chu , Yang Hui , Li Qian , Tao Junhui , Wu Tian
Published: February 2024

Enhancement of the adsorption performance and recyclability of adsorbents is a crucial aspect of water treatment.
Br doping-induced evolution of the electronic band structure in dimorphic and hexagonal SnSe2 thermoelectric materials
Authors: Kim Se-Jun , Heo Minsu , Kim Sang-il , Park Hyunjin , Kim Jeong-Yeon , Seo Won-Seon , Kim Hyun-Sik
Published: February 2024

Br doping in SnSe2 induces a transformation from the native dimorphic phase to a hexagonal phase. The impact of engineering the fraction of the hexagonal phase in SnSe2 is evaluated via the single parabolic band model.
Triplet energy transfer from quantum dots increases Ln(iii) photoluminescence, enabling excitation at visible wavelengths
Authors: Huang Tingting , He Sheng , Ni Anji , Lian Tianquan , Lee Tang Ming
Published: February 2024

Triplet energy transfer from CdS quantum dots enhances europium(iii) emission under visible light excitation.
Long-term performance of hydrogen-bromine flow batteries using single-layered and multi-layered wire-electrospun SPEEK/PFSA/PVDF membranes
Authors: Abbasi Sanaz , Hugo Yohanes Antonius , Borneman Zandrie , Kout Wiebrand , Nijmeijer Kitty
Published: February 2024

The wire-electrospun layer arrangement and composition of dense SPEEK/PFSA/PVDF membranes for long-term hydrogen-bromine flow battery operation is investigated to ensure durable performance with <50% PFSA utilization and ≤60 μm membrane thickness.
A MOF-derived pyrrolic N-stabilized Ni single atom catalyst for selective electrochemical reduction of CO2 to CO at high current density
Authors: Lim Jin Wook , Choo Dong Heon , Cho Jin Hyuk , Kim Jaehyun , Cho Won Seok , Ngome Okello Odongo Francis , Kim Kisoo , Lee Sungwon , Son Junwoo , Choi Si-Young , Kim Jong Kyu , Jang Ho Won , Kim Soo Young , Lee Jong-Lam
Published: February 2024

Electrochemical reduction of CO2 to chemical fuels with a transition metal-based single atom catalyst (SAC) offers a promising strategy to reduce CO2 with high catalytic selectivity.
Novel heat storage ionomer binder for thermal management of Li-ion batteries
Authors: Shen Danni , Han Tingting , Liu Jie , Yang Junwu , Zhou Jinqiu , Li Yufei , Zhou Xi , Wang Zhenkang , Qian Tao , Yan Chenglin
Published: February 2024

A novel heat storage ionomer binder with highly efficient heat-storage ability is proposed to function as an internal temperature conditioner, which allows the battery to function steadily over a wider temperature range.
Construction of a layer-by-layer self-assembled rosemarinic acid delivery system on the surface of CFRPEEK implants for enhanced anti-inflammatory and osseointegration activities
Authors: Zhao Shanshan , Zhou Xingyu , Dang Junbo , Wang Yilong , Jiang Junhui , Zhao Tianhao , Sun Dahui , Chen Chen , Dai Xin , Liu Yan , Zhang Mei
Published: February 2024

Construction of a layer-by-layer self-assembled rosemarinic acid delivery system on the surface of CFRPEEK implants and its biological functions: anti-inflammatory and osteogenesis.
Water monitoring with an automated smart sensor supported with solar power for real-time and long range detection of ferrous iron
Authors: Ozer Tugba , Agir Ismail , Borch Thomas
Published: February 2024

A low-power and smart sensing system for in situ monitoring of iron in water samples.
A solvent-controlled photoresponsive ionic hydrogen-bonded organic framework for encryption applications
Authors: Huang Ming-Feng , Cao Li-Hui , Zhou Bin
Published: February 2024

An ionic hydrogen-bonded organic framework exhibits fast and reversible photochromic properties. Benefiting from the stimuli-responsive property, information encryptions and decryptions integrated with photoresponsivity are successfully designed.
Quantifying hydroxyl radicals generated by a low-temperature plasma using coumarin: methodology and precautions
Authors: Ducrozet Florent , Sebastian Amal , Garcia Villavicencio Cecilia Julieta , Ptasinska Sylwia , Sicard-Roselli Cécile
Published: February 2024

The detection and quantification of hydroxyl radicals (HO˙) generated by low-temperature plasmas (LTPs) are crucial for understanding their role in diverse applications of plasma radiation.
Cs+ conductance in graphene membranes with Ångström-scale pores: the role of pore entrance geometry
Authors: Wagemann Enrique , Kim Na Young , Mitra Sushanta K.
Published: February 2024

Varying pore entrance geometry reveals up to 100% change in ionic conductance for the transport of Cs+ ions in graphene membranes with 3.4 Å pores.
Nature's empowerment: unraveling superior performance and green degradation closed-loop in self-curing fully bio-based benzoxazines
Authors: Yang Mingyuan , Wang Tiancheng , Tian Yazhou , Zhang Haobo , Zhang Junying , Cheng Jue
Published: February 2024

Benzoxazines, renowned for their self-curing properties, high glass transition temperature, and exceptional thermal stability, have faced environmental and biotoxicity concerns despite their remarkable performance.
Enhanced lithium-ion conductivity and interficial stability of Li-IL@Fe-BDC composite polymer electrolytes for solid-state lithium metal batteries
Authors: Liu Liequan , Gong Zikang , Liu Chen , Peng Aiping , Zhang Ze , Yu Ji , Cai Jianxin , Yang Zhenyu
Published: February 2024

The Li-IL@Fe-BDC material successfully confines Li-ILs among Fe-BDCs, releasing more free lithium ions in the PEO matrix, and the LFP/CPE3/Li battery is stabilized for 700 cycles at 1 C.
Mass and mole fractions in calibration-free LIBS
Authors: Völker Tobias , Gornushkin Igor B.
Published: February 2024

Importance of mole or mass fraction representations of concentrations in CF-LIBS.
UV absorption enhanced polydopamine coating
Authors: Yang Zhen , Liu Huijie , Zhao Junyi , Wang Chao , Li Haotian , Wang Xianheng , Yang Ye , Wu Haoxing , Gu Zhipeng , Li Yiwen
Published: February 2024

This article illustrates a facile approach to enhance the UV absorption of PDA coatings by incorporating thiol-heterocycle derivatives. These PDA coatings showed great promise for applications in UV protection, antibacterial and dye degradation.
Robust and ultrasensitive electrochemical detection of ochratoxin a using a highly reactive DNAzyme wired via primer exchange reaction
Authors: Meng Yanling , Zhang Qingxin , Guo Zhiqiang , Wang Huihui , Zhang Mingshuo , Pan Huan , Yue Xudong , Liu Su , Huang Jiadong , Wang Yu
Published: February 2024

We developed a novel and effective electrochemical biosensor for the sensitive detection of OTA using a highly reactive DNAzyme wired via a primer exchange reaction.
Release of extracellular vesicles triggered by low-intensity pulsed ultrasound: immediate and delayed reactions
Authors: Zheng Yiwen , Liu Mengyao , Yu Qian , Wang Rui , Yao Yijing , Jiang Lixin
Published: February 2024

Current study evidence tends to support the notion that ultrasound stimulates the release of extracellular vesicles, but there are still plenty of details that need to be investigated.
Biopolymer-protected graphene-Fe3O4 nanocomposite based wearable microneedle sensor: toward real-time continuous monitoring of dopamine
Authors: M. R. Keerthanaa , Panicker Lakshmi R. , Narayan Roger , Kotagiri Yugender Goud
Published: February 2024

Neurological disorders can occur in the human body as a result of nano-level variations in the neurotransmitter levels.
A eutectogels-catalyzed one-pot multi-component reaction: access to pyridine and chromene derivatives
Authors: Nguyen Phat Ngoc , Nguyen Linh Ho Thuy , Doan Tan Le Hoang , Tran Phuong Hoang , Nguyen Hai Truong
Published: February 2024

The demand for a wide array of functional chemicals and materials has experienced a significant surge in tandem with the advancement of civilization.
A zwitterionic fused-ring framework as a new platform for heat-resistant energetic materials
Authors: Lv Ruibing , Jiang Lan , Wang Jinxin , Huang Shiliang , Song Siwei , Wei Liyuan , Zhang Qinghua , Wang Kangcai
Published: February 2024

A zwitterionic fused-ring based energetic material (ZDPT) was prepared. ZDPT has excellent thermal stability (Td = 347 °C ) and great detonation velocity (D = 8390 m s−1), which endow ZDPT with great potential as a heat-resistant energetic material.
Subphthalocyanine semiconducting cocrystals with efficient super-exchange coupling
Authors: Sun Lingyan , Guo Yuan , He Dan , Dhara Barun , Huang Fei , Yi Yuanping , Miyajima Daigo , Zhang Cheng
Published: February 2024

The SubPc-12H-12F cocrystal was constructed with almost identical packings of SubPc-6F(β). This study proved that the super-exchange coupling can both improve the charge carrier mobility and expand the charge transport channels in cocrystals.
A comprehensive survey of low‐carbon planning and operation of electricity, hydrogen fuel, and transportation networks
Authors: Zhou Yeao , Chen Sheng , Chen Jiayu
Published: February 2024

The trend of global energy systems towards carbon neutrality has led to an escalating interdependency between electricity, hydrogen fuel, and transportation networks. However, the means of surmounting the many challenges confronting the optimal coupling and coordination of electric power, hydrogen fuel, and transportation systems are not sufficiently understood to guide modern infrastructure planning operations. The present work addresses this issue by surveying the extant literature, relevant government policies, and future development trends to evaluate the present state of technology available for coordinating these systems and then determine the most pressing issues that remain to be addressed to facilitate future trends. On the one hand, the users of transportation networks represent flexible consumers of electric power and hydrogen fuel for those connected via devices such as electric vehicles and hydrogen fuel cell vehicles through charging stations and hydrogen refuelling stations. On the other hand, power grids can mitigate the negative effect of random charging behaviours on grid security through time‐of‐use electricity pricing, while excess renewable energy outputs can be applied to generate hydrogen fuel. The findings of this overview offer support for infrastructure planning and operations. Finally, the most urgent issues requiring further research are summarised.
Long‐term and multi‐objective maintenance scheduling of medium voltage overhead lines based on LP metric method
Authors: Moghadam Mehdi Akbari , Bagheri Sajad , Salemi Amir Hosein , Tavakoli Mohammad Bagher
Published: February 2024

Planning maintenance of medium voltage overhead lines is one of the most important issues in the studies on power distribution network, which will prevent and reduce unwanted interruption. In this paper, long‐term maintenance of medium voltage networks was planned by multi‐objective function, including an extended mixed‐integer linear model to optimize costs, energy not supplied (ENS), and average interruption duration index (SAIDI). In addition, the uncertainty about the annual growth rate of the load, the increase in the cost of goods and services and the increase in the selling price of energy as well as various constraints are all included in the desired objective function, which is one of the main innovations of this paper compared to other published studies. To apply the uncertainties, information gap decision theory (IGDT) has been used, and to solve the objective functions, LP‐Metric method has been used. The proposed method was implemented on the standard 11‐bus RBTS network by MATLAB and GAMS. The results showed that three different long‐term maintenance plans proposed here lead to the optimization of the annual maintenance costs of network, reduction in ENS and interruption, and increase in the reliability of the network based on the uncertainty of each feeder.
A low‐cost Raspberry Pi based time domain reflectometer for fault detection in electric fences
Authors: Kiarie Gabriel , wa Maina Ciira , Nyachionjeka Kumbirayi
Published: February 2024

Electric fences used to create protected areas (PAs) are prone to faults that affect their operation. The conventional method of measuring the voltage of the fence periodically to detect faults and walking along the fence to locate the faults is inefficient and time consuming. This paper presents a low‐cost Raspberry Pi time domain reflectometer (TDR) for fault detection and localisation in electric fences. The system is designed using cheap off‐the‐shelf components. It uses time domain reflectometry to detect hard (open and short circuit) faults in electric fences. Time domain reflectometry is a method of detecting and locating faults in electrical cables. The Raspberry Pi TDR is evaluated and it has successfully detected and located open circuit and short circuit faults in electric fences with a mean absolute error of 1.52 m. The Raspberry Pi TDR offers the potential to remotely monitor electric fences autonomously, hence improving their effectiveness.
Comparison of magnetic data products from Solar Orbiter SO/PHI-FDT and SDO/HMI
Authors: Moreno Vacas A. , Orozco Suárez D. , Strecker H. , del Toro Iniesta J. C. , Borrero J. M. , Albert K. , Solanki S. K. , Bailén F. J. , Bellot Rubio L. R. , Hirzberger J. , Sinjan J. , Santamarina Guerrero P. , Valori G. , Albelo Jorge N. , Alvarez-Herrero A. , Appourchaux T. , Blanco Rodríguez J. , Calchetti D. , Feller A. , Fiethe B. , Gandorfer A. , Germerott D. , Gizon L. , Gómez Cama J. M. , Guerrero L. , Gutierrez-Marques P. , Kahil F. , Kolleck M. , Korpi-Lagg A. , Michalik H. , Pérez-Grande I. , Sanchis Kilders E. , Schou J. , Schühle U. , Staub J. , Volkmer R. , Woch J.
Published: February 2024

Context.The Polarimetric and Helioseismic Imager (SO/PHI), on board the Solar Orbiter mission, is the first photospheric magnetograph and tachograph to observe the Sun from outside the Sun-Earth line. The Full Disc Telescope (FDT) of SO/PHI, images the whole solar disk with a spatial resolution that varies with the distance between the Sun and the spacecraft.

Aims.We check for consistency between the magnetic field strength (B), the field inclination (γ), the line-of-sight (LoS) magnetic component (BLoS) and the field azimuth (ϕ), inferred by SO/PHI-FDT and the Helioseismic and Magnetic Imager (HMI), on board Solar Dynamics Observatory (SDO), and obtain linear correlation coefficients among them.

Methods.We use data from both instruments obtained on 8 March 2022, when the angle between SDO and Solar Orbiter was 3.4° and the solar disk showed four developed active regions. Before comparing the magnetic field products of both instruments we perform a precise alignment of the data, including a matching of the plate scale. Further, in order to improve the homogeneity of the compared data products, the SDO/HMI data were convolved with the SO/PHI-FDT point spread function (PSF). The linear correlation coefficients are obtained through a linear regression of SDO/HMI to SO/PHI-FDT.

Results.The two instruments yield comparable magnetic field data products. The slope coefficients for a linear fit are 1.37 forB, 1.11 forγ, 1.35 forBLoSand 1 for the azimuth. The corresponding fit offsets are −94 G, −9.8°, 5.2 G and 0.1°, respectively. The agreement between both instruments is significantly better when we take into account the different spatial resolution of both instruments. The fitting results vary slightly depending on the analyzed active region except for one of the four active regions, which shows larger differences and has been excluded from the comparison. The comparison of the LoS magnetic field products from SDO/HMI at 45 s and 720 s with SO/PHI-FDT shows a slope value of 1.17, with the offset less than 6 G, in both cases.
L’ADN fœtal révélé
Authors: Jordan Bertrand
Published: February 2024

New developments in the analysis of maternal cell-free DNA now allow complete analysis of the foetal exome. This makes possible an important extension of the breadth of prenatal diagnostics but raises significant ethical questions.
Multicenter prospective randomized controlled clinical trial comparing the pocket-creation method with and without single-clip traction of colonic endoscopic submucosal dissection
Authors: Morikawa Takaaki , Nemoto Daiki , Kurokawa Tomohiro , Yamashina Takeshi , Hayashi Yoshikazu , Kitamura Masafumi , Okada Masahiro , Takezawa Takahito , Nakajima Yuki , Kowazaki Yuka , Fukuda Hisashi , Nomura Tatsuma , Lazaridis Nikolaos , Fukushima Noriyoshi , Sunada Keijiro , Yamamoto Hironori
Published: February 2024

Background The pocket-creation method (PCM) was developed to overcome the technical difficulties of endoscopic submucosal dissection (ESD), although opening the pocket remains challenging. We developed a novel technique of PCM with single-clip traction (PCM-CT), which uses a reopenable clip as a traction device to maintain stability during the procedure. No prospective study has compared the efficacy of PCM-CT and PCM. This study aimed to investigate the effectiveness of PCM-CT vs. PCM in a randomized controlled trial.

Methods This randomized controlled clinical trial was conducted at four Japanese institutions. Patients with superficial colorectal neoplastic lesions were included following Japanese guidelines for colorectal cancer. Seven moderately experienced endoscopists performed the ESD procedures using either PCM-CT or PCM.

Results 100 patients were enrolled in the study. Compared with PCM, PCM-CT achieved significantly faster mean (SD) dissection speed (21.4 [10.8] vs. 27.0 [14.5] mm2/min [95%CI 0.5 to 10.7], P = 0.03), and reduced the mean procedure time (81.8 [57.9] vs. 64.8 [47.6] minutes [95%CI –38.2 to 4.3], P = 0.12) and pocket-opening time (37.8 [33.0] vs. 30.0 [28.9] minutes [95%CI –20.2 to 4.6], P = 0.22). En bloc and R0 resection rates were not significantly different between the two groups (100% vs. 100%, P >0.99; 100% vs. 96%, P = 0.50, respectively). No significant differences were observed in adverse events between the two groups.

Conclusion ESD facilitated by the novel PCM-CT method appeared to be significantly faster than PCM. Both methods achieved high R0 resection rates.
Cross-Talk Between Thyroid Disorders and Nonalcoholic Fatty Liver
Disease: From Pathophysiology to Therapeutics
Authors: Yang Yan , Xiao Jiyuan , Qiu Wen , Jiang Luxia
Published: February 2024

The medical community acknowledges the presence of thyroid disorders and
nonalcoholic fatty liver disease (NAFLD). Nevertheless, the interconnection
between these two circumstances is complex. Thyroid hormones (THs), including
triiodothyronine (T3) and thyroxine (T4), and thyroid-stimulating hormone (TSH),
are essential for maintaining metabolic balance and controlling the metabolism
of lipids and carbohydrates. The therapeutic potential of THs, especially those
that target the TRβ receptor isoform, is generating increasing interest. The
review explores the pathophysiology of these disorders, specifically examining
the impact of THs on the metabolism of lipids in the liver. The purpose of this
review is to offer a thorough analysis of the correlation between thyroid
disorders and NAFLD, as well as suggest potential therapeutic approaches for the
future.
Balloon-Assisted Stent Visualization: A Simple Technique for Precise Measurement of Previously Placed Stent Diameter
Authors: Sakamoto Manato , Yokoya Shigeomi , Takezawa Hidesato , Ichihashi Midori , Kishida Kengo , Oka Hideki
Published: February 2024

Stent-assisted coil embolization is effective for treating intracranial aneurysms, improving outcomes and reducing recurrence rates. However, accurately measuring the diameter of a previously placed stent during imaging can be challenging due to coil artifacts. This poses difficulties in determining the coil packing and size of additional stents needed during retreatment. In a reported case, the use of a balloon enabled precise assessment of stent deployment. A 50-year-old male with a history of basilar artery-left superior cerebellar artery aneurysm underwent coil embolization, direct clipping, and stent-assisted coil embolization (SAC) over a span of 14 years. However, the aneurysm showed reenlargement over time. To address the recurrence, a balloon was used to assess the previously placed Neuroform Atlas stent. Additional coils were inserted outside the stent, and a Low-profile Visualized Intraluminal Support Blue stent was added. Postoperatively, there were no new neurological issues, and a follow-up magnetic resonance imaging showed no ischemic lesions. Balloon-assisted stent visualization (BASV) may be a useful method in the retreatment of SAC. It has the potential to provide valuable information for treatment planning.
“Good,” “Hopeless,” and “Alright”: People with Aphasia Expressing Their Opinions on Their Rehabilitation Experiences
Authors: Sherratt Sue
Published: February 2024

Treatment for people with aphasia mainly concentrates on facilitating the communication of needs or providing facts. This focus is in danger of downplaying the significance of the expression of attitudes and emotion. Evaluative expression is critical for recreating identity and social interaction. However, the linguistic expression of emotions following aphasia has been insufficiently explored. This study aimed to determine which semantic-lexical devices people with aphasia used to express their opinions and views about their clinicians and rehabilitation. In-depth interviews with 50 people with aphasia describing their emotions during their rehabilitation were analyzed using the appraisal framework comprising appreciation, affect, and judgment. Speakers also graded their attitudes toward people, things, or events. Almost half of instances expressed appreciation, over one-third expressed judgment, and about 16% expressed affect. Amplification of emotions was used frequently, in over 40% of instances. Affective difficulties following aphasia and other brain injuries are among the most important factors for rehabilitation, social reintegration, and the burden on family members. To ameliorate these issues, the focus of rehabilitation in aphasia needs to shift from expressing needs toward facilitating the expression of opinions and feelings and providing people with aphasia with the opportunities and means to express their views on their healthcare.
Traditional Chinese medicinal leaves shine bright as the base for carbon dots
Authors: Shapiro Maura
Published: February 2024

Chlorophyll-structured carbon dots achieve high color purity and luminescence for future, non-toxic, biocompatible, and affordable LEDs.
Identifying cellular metabolic pathways with label-free imaging and neural networks
Authors: Thompson Avery
Published: February 2024

Machine learning identifies individual cell metabolism from fluorescence lifetime images for informing cancer treatments and immune therapies.
Strong contact resistance effects on vertical carrier density profile and surface trap density in WSe2 multilayers
Authors: Choi Dahyun , Chae Minji , Han Yeongseo , Joo Min-Kyu
Published: February 2024

Conducting channel migration depending on the thickness of 2D multilayers has been demonstrated theoretically and experimentally by ascribing it to the high interlayer barrier and thickness-dependent carrier mobility via an electrostatic gate and drain bias. However, the unique charge carrier transport feature is significantly suppressed when a high contact resistance is exhibited at the metal-to-2D semiconducting multilayers, in addition to the inherent tunneling barrier between neighboring layers. Herein, we report strong channel access contact resistance effects on the vertical carrier density profile and surface trap density along the thickness of WSe2 multilayer transistors. For the constructed top-contact electrodes demonstrating pseudo-ohmic behavior, we observed clear double humps in the second derivative of the transconductance (dgm) curves, implying conducting channel migration along the c-axis of the WSe2 multilayers, regardless of the drain bias (VD) conditions. Meanwhile, at the bottom-contact electrodes, demonstrating a relatively high contact resistance effect, the second hump of dgm exclusively appears at high VD regimes (3.0 V ≤ VD), signaling the restricted channel migration caused by poor contact quality, even in identical WSe2 multilayers. We further confirmed this distinct feature in dgm curves by connecting the top and bottom electrodes to support our observations. Furthermore, low-frequency noise measurements were performed to determine the surface trap density of the supporting dielectrics and the relevant carrier scattering mechanism. Our study provides valuable insight into the effects of contact resistance on carrier transport and the scattering mechanism in WSe2 multilayer transistors, shedding light on the optimization of device performance and contact quality.
Thomson scattering measurements in the krypton plume of a lanthanum hexaboride hollow cathode in a large vacuum test facility
Authors: Suazo Betancourt Jean Luis , Butler-Craig Naia , Lopez-Uricoechea Julian , Bak Junhwi , Lee Dongho , Steinberg Adam M. , Walker Mitchell L. R.
Published: February 2024

Laser Thomson scattering is a minimally intrusive diagnostic technique for determining electron temperature, density, and bulk velocity in plasma systems. Advances in technology have made possible the application of Thomson scattering to electric propulsion-relevant plasma systems, with reported electron number-density detection limits as low as 1×1016 m−3, and electron temperatures from one-to-tens eV. However, the implementation of laser Thomson scattering in large vacuum testing facilities, wherein electric propulsion devices are tested, remains a challenge. This work presents the implementation of a laser Thomson scattering system in a large vacuum test facility at the Georgia Tech High Power Electric Propulsion Laboratory. The diagnostic was optimized for maximum light-collection efficiency and ease of re-alignment while the facility is at vacuum. The high light-collection efficiency allowed reduced accumulation times to achieve the target detection limit of 1×1017 m−3. The diagnostic is used to measure axial electron property profiles in the near-field plume of a lanthanum hexaboride hollow cathode operating at 25 A on krypton at a background pressure of 1.3×10−6 Torr—Kr. The diagnostic is quantitatively compared to similar systems in the literature. The resulting axial points, collected from 2 to 8 mm downstream of the cathode keeper orifice, are qualitatively and quantitatively compared with simulations and experimental measurements made with electrostatic probes and laser-induced fluorescence. The main quantitative difference between measured values and results is the one to two order of magnitude difference in the peak electron density, being attributed to the relative size and location of the external anode with respect to the cathode keeper.
Manually pressurized droplet digital PCR chip for rapid SARS-CoV-2 diagnostics
Authors: Elomaa Pinja , Ojalehto Tuomas , Kumar Darshan , Jokinen Ville , Saavalainen Päivi
Published: February 2024

Droplet digital PCR (ddPCR) is a technique in which PCR reaction is divided into thousands of nanoliter-sized droplets and has proven to be a great tool in virus diagnostics. Compared to the gold standard system quantitative real-time PCR (RT-qPCR), ddPCR functions particularly well when dealing with samples with low template counts, such as viral concentration. This feature makes the technique suitable for early detection of the virus. In this study, a novel portable PDMS ddPCR chip is introduced. The chip functions without external pumps using manual pressurization with a multichannel pipet. The created droplets are monodispersed and form a monolayer on the chip's collection chamber, from where they can be effortlessly imaged. Droplets were analyzed and counted using artificial intelligence. The use of the manually pressurized chip was demonstrated for a SARS-CoV-2 assay, which takes advantage of isothermal strand invasion-based amplification (SIBA) technology, allowing quick and accurate, even point-of-care analysis of the sample. The results demonstrate that SIBA assays can be divided into nanoliter-sized droplets and used as quantitative assays, giving an approximation of the samples' viral count.
Hole-tunneling Si0.82Ge0.18/Si triple-barrier resonant tunneling diodes with high peak current of 297 kA/cm2 fabricated by sputter epitaxy
Authors: Suda Yoshiyuki , Hirose Nobumitsu , Tsukamoto Takahiro , Wakiya Minoru , Shinkawa Ayaka , Kasamatsu Akifumi , Matsui Toshiaki
Published: February 2024

Hole-tunneling Si0.82Ge0.18/Si asymmetric triple-barrier (TB) resonant tunneling diodes (p-RTDs) were created by sputter epitaxy instead of conventional chemical vapor phase epitaxy. As a result, a peak current density (PCD) of 297 kA/cm2 with a peak-to-valley current ratio of 7.3 was recorded at room temperature. The observed high planarity of the films grown by sputter epitaxy is also considered one of the factors behind the high PCD. From the results of self-consistent theoretical calculations of current–voltage characteristics using box-shaped potentials as a first approximation and considering space charge effects of quantum wells, heavy-hole-to-heavy-hole and light-hole-to-light-hole state transitions under the tunneling conditions of the TB potential structure applied in this study were found to be inherent current paths. Moreover, the light and heavy hole currents contribute almost equally to the overall device current, resulting in a theoretical PCD of 637 kA/cm2, which is close to the experimental result. Further analytical simulations with adjusted series resistance and thickness of the nondoped layer allowed the alignment of the theoretically obtained PCD voltage position with the experimentally obtained one. Thus, the theoretical and analytical calculations explain the operation mechanisms of SiGe/Si p-RTDs, and the proposed fabrication method using our sputter epitaxy method is very useful for the actual production of high-PCD SiGe/Si p-RTDs operating at room temperature.
Electron knock-on damage effects on electron magnetic chiral dichroism of magnetic metals using cobalt as a model
Authors: Hu Q. , Fu X. , Zeng Z. , Li J. , Liu G. , Zheng C. , Zhang L. , Huang X.
Published: February 2024

Electron magnetic chiral dichroism (EMCD) is a high-resolution technique currently in development for quantitative magnetic measurements using transmitted electrons. However, the inevitable electron damage to materials can be a significant yet easily overlooked factor affecting the quantification accuracy. This work experimentally investigated the electron knock-on damage effects on EMCD of magnetic metals using metallic cobalt as a model. Three issues are involved in the metal-surface damage process. It was revealed that under sustained electron irradiation during spectra acquisition, gradual removal of the thin surface oxidation layer, rather than a simple continuous thickness reduction that changes the diffraction and plural scattering conditions, can lead to notable residual nonmagnetic components in EMCD spectra and may make the quantified result of the orbital-to-spin moment ratio remarkably higher than the actual value. It was, thus, proposed to pay great attention to the surface oxidation and to minimize the effect of the oxidation layer by performing electron irradiation on the target area prior to EMCD experiments. A further experiment was additionally proposed to quantify the impact of thickness reduction on the magnetic components of momentum-resolved electron energy-loss spectra and the EMCD quantification. This study advances the application of EMCD in magnetic metals.
Characterization of iron(III) in aqueous and alkaline environments with ab initio and ReaxFF potentials
Authors: Riefer Arthur , Hackert-Oschätzchen Matthias , Plänitz Philipp , Meichsner Gunnar
Published: February 2024

The iron(III) complexes [Fe(H2O)n(OH)m]3−m (n + m = 5, 6, m ≤ 3) and corresponding proton transfer reactions are studied with total energy calculations, the nudged elastic band (NEB) method, and molecular dynamics (MD) simulations using ab initio and a modification of reactive force field potentials, the ReaxFF-AQ potentials, based on the implementation according to Böhm et al. [J. Phys. Chem. C 120, 10849–10856 (2016)]. Applying ab initio potentials, the energies for the reactions [Fe(H2O)n(OH)m]3−m + H2O → [Fe(H2O)n−1(OH)m+1]2−m + H3O+ in a gaseous environment are in good agreement with comparable theoretical results. In an aqueous (aq) or alkaline environment, with the aid of NEB computations, respective minimum energy paths with energy barriers of up to 14.6 kcal/mol and a collective transfer of protons are modeled. Within MD simulations at room temperature, a permanent transfer of protons around the iron(III) ion is observed. The information gained concerning the geometrical and energetic properties of water and the [Fe(H2O)n(OH)m]3−m complexes from the ab initio computations has been used as reference data to optimize parameters for the O–H–Fe interaction within the ReaxFF-AQ approach. For the optimized ReaxFF-AQ parameter set, the statistical properties of the basic water model, such as the radial distribution functions and the proton hopping functions, are evaluated. For the [Fe(H2O)n(OH)m]3−m complexes, it was found that while geometrical and energetic properties are in good agreement with the ab initio data for gaseous environment, the statistical properties as obtained from the MD simulations are only partly in accordance with the ab initio results for the iron(III) complexes in aqueous or alkaline environments.
Actively switchable spintronic terahertz emission with arbitrary polarization states
Authors: Wang Yangkai , Cheng Hao , Li Weiwei , Liu Zheng , Jia Xiangyu , Huang Qiuping , Lu Yalin
Published: February 2024

Flexible manipulation of the polarization state is essential for the practical application of terahertz (THz) waves in many fields. However, the lack of effective, high-quality polarization-tunable THz sources hinders the further development of THz technology. Here, we demonstrate an actively switchable spintronic THz source with polarization states among linear, circular, and elliptical states in the CoFeB/Pt/SiO2(sub)/Ta/Co/IrMn structure by using the antiferromagnet/ferromagnet exchange bias effect, as well as a temporary magnetic field to combine the magnetization directions, and designing the thickness of the substrate to achieve a suitable phase difference. In addition, the chirality, ellipticity, and azimuth of the THz waves can be manipulated arbitrarily by controlling the magnetization combination. More importantly, using rotating motors and electromagnets enables fully automated operations. This highly efficient, polarization-tunable THz source meets most of the existing needs, and its low cost and small size make it more suitable for integration into various devices. It paves the way for accelerating THz spintronic devices and unveiling mechanisms in condensed matter physics.
Ultralow 1/f noise in epigraphene devices
Authors: Shetty N. , Chianese F. , He H. , Huhtasaari J. , Ghasemi S. , Moth-Poulsen K. , Kubatkin S. , Bauch T. , Lara-Avila S.
Published: February 2024

We report the lowest recorded levels of 1/f noise for graphene-based devices, at the level of SV/V2=SI/I2=4.4×10−16 (1/Hz), measured at f = 10 Hz (SV/V2=SI/I2 < 10−16 1/Hz for f > 100 Hz) in large-area epitaxial graphene on silicon carbide (epigraphene) Hall sensors. This performance is made possible through the combination of high material quality, low contact resistance achieved by edge contact fabrication process, homogeneous doping, and stable passivation of the graphene layer. Our study explores the nature of 1/f noise as a function of carrier density and device geometry and includes data from Hall sensors with device area range spanning over six orders of magnitude, with characteristic device length ranging from L = 1 μm to 1 mm. In optimized graphene Hall sensors, we demonstrate arrays to be a viable route to improve further the magnetic field detection: a simple parallel connection of two devices displays record-high magnetic field sensitivity at room temperature, with minimum detectable magnetic field levels down to Bmin = 9.5 nT/√Hz. The remarkable low levels of 1/f noise observed in epigraphene devices hold immense capacity for the design and fabrication of scalable epigraphene-based sensors with exceptional performance.
Shear rheology senses the electrical room-temperature conductivity optimum in highly Li doped dinitrile electrolytes
Authors: Lansab Sofiane , Schwan Tobias , Moch Kevin , Böhmer Roland
Published: February 2024

Glutaronitrile (GN) doped with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) at concentrations below and above the room-temperature conductivity optimum near 1M of Li salt is investigated using dielectric spectroscopy and shear rheology. The experiments are carried out from ambient down to the glass transition temperature Tg, which increases considerably as LiTFSI is admixed to GN. As the temperature is lowered, the conductivity optimum shifts to lower salt concentrations, while the power-law exponents connecting resistivity and molecular reorientation time remain smallest for the 1M composition. By contrast, the rheologically detected time constants, as well as those obtained using dielectric spectroscopy, increase monotonically with increasing Li salt concentration for all temperatures. It is demonstrated that the shear mechanical measurements are, nevertheless, sensitive to the 1M conductivity optimum, thus elucidating the interplay of the dinitrile matrix with the mobile species. The data for the Li doped GN and other nitrile solvents all follow about the same Walden line, in harmony with their highly conductive character. The composition dependent relation between the ionic and the reorientational dynamics is also elucidated.
Post-impact lamella evolution of drop impact on superhydrophobic cylindrical surfaces at high Weber number
Authors: Naveen P. T. , Khare Ashish , Harikrishnan A. R.
Published: February 2024

Drop surface interaction is omnipresent in nature and vital to many engineering applications. Most previous studies on drop impact dynamics on superhydrophobic cylindrical surfaces have focused on low-impact Weber (We) numbers, wherein the asymmetric bouncing behavior is the prominent outcome. However, it is observed that an impacting drop at higher impact We numbers (>100) exhibits more complex dynamics. The asymmetric post-impact lamella evolution in axial, and azimuthal directions are analyzed in detail. At higher impact velocities, the lamella expands in an azimuthal direction over the solid cylindrical surface, sweeping a certain angle followed by further expansion in air and over the solid surface until attaining the critical detachment angle or swiping angle, which is found to be a function of surface curvature and impact velocity. Thereafter, the expansion proceeds only in the air until the lamella completely shatters away, indicating the absence of a retraction phase in the azimuthal direction contrary to that during low-velocity impact. Lamella nucleation and film rupturing together, along with the ejection of satellite droplets, further add complexity. The present experimental study comprehensively evaluates the effect of higher Weber numbers (We up to 660) and surface curvature. Universal scaling relations are proposed for the lamella evolution in the axial and azimuthal directions based on the impact parameters to rationalize the same. A minimization of the surface energy approach has been hypothesized to predict the detachment angle utilizing the proposed scaling relations and is found to predict well with the experimental data.
Role of tungsten disulfide quantum dots in specific protein–protein interactions at air–water interface
Authors: Kaur Harsharan , Garg Mayank , Tomar Deepak , Singh Suman , Jena Kailash C.
Published: February 2024

The intriguing network of antibody–antigen (Ab–Ag) interactions is highly governed by environmental perturbations and the nature of biomolecular interaction. Protein–protein interactions (PPIs) have potential applications in developing protein-adsorption-based sensors and nano-scale materials. Therefore, characterizing PPIs in the presence of a nanomaterial at the molecular level becomes imperative. The present work involves the investigation of antiferritin–ferritin (Ab–Ag) protein interactions under the influence of tungsten disulfide quantum dots (WS2 QDs). Isothermal calorimetry and contact angle measurements validated the strong influence of WS2 QDs on Ab–Ag interactions. The interfacial signatures of nano–bio-interactions were evaluated using sum frequency generation vibration spectroscopy (SFG-VS) at the air–water interface. Our SFG results reveal a variation in the tilt angle of methyl groups by ∼12° ± 2° for the Ab–Ag system in the presence of WS2 QDs. The results illustrated an enhanced ordering of water molecules in the presence of QDs, which underpins the active role of interfacial water molecules during nano–bio-interactions. We have also witnessed a differential impact of QDs on Ab–Ag by raising the concentration of the Ab–Ag combination, which showcased an increased inter-molecular interaction among the Ab and Ag molecules and a minimal influence on the methyl tilt angle. These findings suggest the formation of stronger and ordered Ab–Ag complexes upon introducing WS2 QDs in the aqueous medium and signify the potentiality of WS2 QDs relevant to protein-based sensing assays.
Quantum random number generator based on LED
Authors: Moeini Mohammadreza , Akbari Mohsen , Mirsadeghi Mohammad , Naeij Hamid Reza , Haghkish Nima , Hayeri Ali , Malekian Mehrdad
Published: February 2024

Quantum random number generators (QRNGs) produce random numbers based on the intrinsic probabilistic nature of quantum mechanics, making them true random number generators. In this paper, we design and fabricate an embedded QRNG that produces random numbers based on fluctuations of spontaneous emission and absorption in a light-emitting diode. To achieve a robust and reliable QRNG, we compare some usual post-processing methods and select the finite impulse response method for a real-time device. This device could pass the National Institute of Standards and Technology tests, the generation rate is 1 Mbit/s, and the randomness of the output data is invariant in time.
Sputtered NbN films for ultrahigh performance superconducting nanowire single-photon detectors
Authors: Stepanov Ilya A. , Baburin Aleksandr S. , Kushnev Danil V. , Sergeev Evgeniy V. , Shmonina Oksana I. , Matanin Aleksey R. , Echeistov Vladimir V. , Ryzhikov Ilya A. , Panfilov Yuri V. , Rodionov Ilya A.
Published: February 2024

At the present time, ultrahigh performance superconducting nanowire single-photon detectors are the key elements in a variety of devices from biological research to quantum communications and computing. Accurate tuning of superconducting material properties is a powerful resource for fabricating single-photon detectors with desired properties. Here, we report on the major theoretical relations between ultrathin niobium nitride (NbN) film properties and superconducting nanowire single-photon detector characteristics, as well as the dependence of ultrathin NbN film properties on reactive magnetron sputtering recipes. Based on this study, we formulate the exact requirements for ultrathin NbN films for ultrahigh performance superconducting nanowire single-photon detectors. Then, we experimentally studied the properties of ultrathin NbN films (morphology, crystalline structure, critical temperature, and sheet resistance) on silicon, sapphire, silicon dioxide, and silicon nitride substrates sputtered with various recipes. We demonstrate ultrathin NbN films (obtained with more than 100 films deposition) with a wide range of critical temperature from 2.5 to 12.1 K and sheet resistance from 285 to 2000 Ω/sq and report a sheet resistance evolution of more than 40% within two years. Finally, we found out that one should use ultrathin NbN films with a specific critical temperature near 9.5 K and a sheet resistance of about 350 Ω/sq for ultrahigh performance state-of-the-art superconducting nanowire single-photon detectors at 1550 nm wavelength.
Fast and robust multilevel optoelectronic memory based on van der Waals heterostructure
Authors: Liu Tao , Wang Yue , Cao Yi , Tan Feixia , Li Honghong , Wang Tinghao , Xiang Du
Published: February 2024

Optoelectronic memory (OEM) has attracted tremendous attention for its great potential to boost the storage capacity of memory chips and break through the von Neumann bottleneck in the post-Moore era. Two-dimensional (2D) van der Waals (vdW) heterostructures, formed by artificially stacking different 2D layered materials, offer tremendous possibilities in OEMs due to their extraordinary capability to integrate and process optical/electrical signals. However, the realization of 2D vdW OEMs with high writing speed and robust memory performance has long been challenging. Here, we report a 2D vdW OEM consisting of tungsten diselenide (WSe2) and hexagonal boron nitride, which functions based on the fast charge transfer dynamics at a 2D interface. The OEM demonstrates high writing speed reaching up to 50 μs, approximately one order of magnitude faster than those of other 2D OEMs. Moreover, the outstanding robustness of such OEM is demonstrated by long retention time exceeding 14 days, together with a broad temperature endurance window from 100 to 420 K. Additionally, through continuously switching laser pulse on the OEM, we achieve 17 distinct current levels (over 4-bit storage) with random access. Our findings envision 2D vdW heterostructure-based OEM as a potential platform to overcome the “memory wall” in the conventional von Neumann configuration and to promote a promising paradigm for big data storage.