bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perturbation Theory
Authors: Mathew K. T. 
Published: December 2024

Abstract
The theoretical techniques for cavity perturbation were originally developed for microwave cavities. These cavities are basically resonant devices. A variety of resonant devices such as waveguide and coaxial cavities, reentrant cavity, split ring resonator, and dielectric resonator are available. Perturbation methods otherwise known as cavity‐perturbation methods based on perturbation theory are simple and accurate methods to solve many of the electromagnetic field problems. This article envisages the basic concepts to evolve the perturbation theory from Maxwell's fundamental equations. Different approaches to this problem are also tackled. The necessary modifications to perturbation theory developed by different authors are also included. The merits, drawbacks, and possible errors of this technique and a few of the important applications are discussed.
Electromagnetic Bandgap‐Assisted Bandpass Filters
Authors: Karmakar Nemai C. , Mollah Mohammad N. 
Published: December 2024

Abstract
Electromagnetic bandgap structures (EBGSs) are playing a vital role in enhancing the performance of microwave devices. EBG materials are periodic structures that exhibit wide bandpass and band‐rejection properties at microwave frequencies. The introduction of periodic perturbation such as dielectric rods, holes, and patterns in waveguides and PCB substrates has resulted in the development of EBGSs, which are also termed photonic bandgap (PBG) materials. The EBGs can suppress the unwanted higher‐order harmonics of a reference BPF. We used uniform, binomially distributed EBGs and dumbbell‐shaped defected ground structure (D‐DGS) to suppress the harmonics of a BPF. It was found that D‐DGS is a potential candidate for harmonic suppression. Presently, we have used rectangular EBGs instead of square‐patterned EBGs. Here, we have used two narrower slots to form modified D‐DGS. They provide the best performance and are capable of suppressing the average second and third harmonics, 55 and 43 dB, respectively.
A Multifunctional Crosslinked F‐Free Binder for MnO2 Microparticle Thick Cathode in Aqueous Zinc‐Ion Batteries
Authors: Choi Sunghun , Seo Joon Kyo , Park Hyunseo , Park Ji Hyun , Kim Sang Woo , Shin Seung Woo , Bang Joo An , Jung Kyu‐Nam , Kim Byung Gon 
Published: December 2024

AbstractIn pursuit of a carbon‐neutral society, extensive research has been conducted on Zn‐MnO2 batteries for their application in energy storage systems. Most efforts have focused on enhancing active material performance at the lab scale, with less attention on high‐loaded electrodes incorporating micro‐sized MnO2 for practical application. Although thick electrodes are required to improve the energy density of cells, unwanted issues such as poor wettability, Mn2+ dissolution, and low adhesion of the electrodes should be addressed to activate these high‐loaded electrodes. To overcome these problems, a multifunctional F‐free hydrophilic crosslinked (HPC) binder is proposed. Unlike F‐containing polyvinylidene fluoride and non‐crosslinked HPC binders showing weak adhesion and binder dissolution, respectively, the HPC binder exhibits hydrophilic, physically stable, and environmentally friendly natures. Moreover, due to the presence of carboxylate groups showing strong adsorption to eluted Mn2+ ions, the Mn2+ migration to the anode side is largely suppressed. Benefiting from these interesting features, the HPC cell exhibits stable cell operation by minimizing the accumulation of irreversible Zn‐vernadite, owing to maintaining the electrode integrity at a practical level of 13.3 mg cm−2. This study highlights the importance of binder design, enabling the use of thick electrodes as a step toward the commercialization of Zn–MnO2 batteries.
Engineering CoN4 and FeN4 Dual Sites with Adjacent Nanoclusters on Flexible Porous Carbon Fibers for Enhanced Electrocatalytic Oxygen Reduction and Evolution
Authors: Lu Zhe , Wang Zhe , Yang Zhenbei , Jin Xiaoyan , Tong Li , Xu RuoJie , Kong Kexin , Zhang Yifan , Wang Yong , Liu Yipu , Meng Linxing , Pan Zhijuan , Hwang Seong‐Ju , Li Liang 
Published: December 2024

AbstractDual‐atom catalysts (DACs) possess tunable electronic structures and efficient atom utilization, making them highly promising for catalyzing the oxygen reduction reaction/oxygen evolution reaction (ORR/OER). However, achieving high catalytic activity and stability for both ORR and OER in DACs remains a challenge. Herein, a flexible membrane of porous carbon fiber anchored with atomically scattered CoN4/FeN4 dual sites and adjacent Co2Fe2/Fe5 nanoclusters (Co, Fe‐DACs/NCs@PCF) is synthesized. The local geometry and electronic structure of the CoN4/FeN4 sites, which act as reaction centers for ORR/OER, are finely regulated by the neighboring Co2Fe2/Fe5 nanoclusters. This unique structure imparts Co, Fe‐DACs/NCs@PCF with exceptional activity and durability toward ORR/OER, outperforming the performance of single‐atom catalysts containing only CoN4 or FeN4 sites, as well as commercial Pt/C and RuO2 catalysts. Zinc–air battery employing a Co, Fe‐DACs/NCs@PCF cathode exhibits outstanding stability, maintaining cyclability for over 1500 h, outperforming a Pt/C + RuO2 air cathode. Theoretical calculations highlight distinct synergies between Fe5 (Co2Fe2) clusters and FeN4 (CoN4) sites, which optimize the coupling strength of Fe(Co)─OH at the potential‐determining steps and thus improve ORR (OER) catalytic kinetics. This study lays a theoretical and practical foundation for rational design of heterostructure catalysts featuring coexisting DACs and nanoclusters within porous carbon fibers.
Superior Electrocaloric Performance Enabled by Highly Robust Monomorphic Ferrodistortion in NaNbO3‐Based Relaxor
Authors: Li Feng , Ji Xiaoli , Wang Xiangjian , Dai Changshun , Wang Xuan , Chen Siyu , Liu Wei , Long Mingsheng , Shan Lei , Qi He , Wang Jianli , Wang Chunchang , Cheng Zhenxiang 
Published: December 2024

AbstractA synergistic realization of high electrocaloric effect (ECE) and excellent temperature stability in ferroelectrics are foundation for practical applications, which is, however, a major challenge in ferroelectric cooling community thus far. In confront with this long‐standing issue, an emergent monomorphic ferrodistortion strategy in NaNbO3‐based relaxor is proposed with flexible tetragonal polar nanoregions immersing in short‐range oxygen octahedral tilt. This not only contributes to large quantities of polar entities to increase entropy change but also produces highly robust oxygen octahedral tilt to persist ferroelectricity and obstruct thermal agitations. Therefore, a high ΔT of 0.96 K and an ultrawide temperature span ΔTspan of 110 K with a record‐high figure of merit of 4.74 is achieved in Ta‐doped NaNbO3‐BaTiO3 ceramics and these superior EC performances present a remarkable breakthrough in ferroelectric bulks cooling. This work thus provides an innovative way of utilizing ferrodistortive relaxor feature with polar nanoregions immersing in oxygen octahedral tilt to simultaneously boost EC value and temperature stability and thus monomorphic ferrodistortion is proposed as an effective strategy to develop high‐performance entropy‐change materials.
A Novel Cu and Ag Bearing High‐Entropy Alloy With Remarkable Antibacterial, Antiviral and Anti‐Microbial Corrosion Performances
Authors: Zhou Enze , Yang Yi , Li Jianlin , Ren Guangyu , Li Lingke , Li Zhong , Lu Yiping , Gu Tingyue , Wang Fuhui , Xu Dake 
Published: December 2024

AbstractThe development of antibacterial and antiviral high‐entropy alloys (HEAs) incorporating copper has attracted widespread attention. However, the segregation of Cu in HEAs can result in detrimental effects on their mechanical properties and corrosion resistance. Herein, two novel HEAs, CoCrCu0.3FeNi‐Ag(1.8 wt.%) (Cu‐AgHEA) and CoCrFeNi‐Ag0.6 (AgHEA), are designed to address these concerns. The yield strength of Cu‐AgHEA is approximately 400 MPa, surpassing those of CoCrCuFeNi (CuHEA) by 1.3 times, and 304 stainless steel by 1.9 times. The abiotic corrosion resistance of Cu‐AgHEA is one order of magnitude greater than that of CuHEA. Moreover, Cu‐AgHEA demonstrates a remarkable antibacterial efficacy of 99.9% against marine bacteria, surpassing that of AgHEA. The very good bactericidal effect of Cu‐AgHEA is attributed to the increased release of Cu and Ag ions, leading to higher concentrations of reactive oxygen species causing bacterial cell damage. Furthermore, Cu‐AgHEA imparts remarkable antiviral characteristics. After 24‐hour treatment, the Cu‐AgHEA surface effectively deactivated approximately 99% of SARS‐CoV‐2 (COVID‐19) virus, rendering it non‐infectious. These findings present an attractive route to advance materials that integrate structure and function, resulting in exceptional overall performances.
Engineered Energy Transfer in Room Temperature Phosphorescent Materials for Time‐Resolved Dual‐Mode Encryption
Authors: Ren Miao , Zhang Shuai , Wu Jie , Hu Qingsong , Cao Sheng , Zou Bingsuo , Yin Zixi , Yu William W. , Zeng Ruosheng 
Published: December 2024

AbstractRoom temperature phosphorescence (RTP) materials are of significant attentions due to their unique optical properties and potential applications in anti‐counterfeiting and information security. However, single spatial resolution anti‐counterfeiting decryption methods fail to meet high‐level security demands. A novel dual‐mode information encryption strategy based on self‐trapped exciton (STE) fluorescence and phosphorescence is proposed. By introducing ns2 metal ions into the zero‐dimensional organic–inorganic hybrid metal halide (Ph3S)2SnCl6, energy transfer pathways from the S1 and Tn energy levels to the STEs are constructed, enabling precise control of phosphorescence performance. This material exhibited STE fluorescence‐phosphorescence dual‐mode optical properties with different afterglow time, which can be utilized to develop high‐performance time‐resolved cryptographic systems. Femtosecond transient absorption experiments indicated that the energy transfer rate from the S1 to STEs significantly affected the time‐resolved characteristics of long afterglow materials. The potential of this material in time‐resolved cryptographic systems is demonstrated, enhancing security through time‐resolved multi‐level encryption and providing a new avenue for advanced anti‐counterfeiting and information security.
Beyond Fertilizers: NH4ZnPO4 for the Reversible Chemical Storage of Ammonia
Authors: Kozawa Takahiro , Hashiba Tai , Fukuyama Kayo , Abe Hiroya , Morita Shu , Osada Minoru , Naito Makio 
Published: December 2024

AbstractEnhancing NH3 as a carbon‐free energy carrier of H2 and next‐generation fuel is a promising approach for a sustainable society. Chemically storing NH3 molecules in crystal structures offers better selectivity and reusability than storage in traditional porous materials based on physicochemical adsorption; however, designing materials that can be reversibly stored in structural gaps is still a significant challenge. Herein, the use of NH4ZnPO4, which is previously used as a fertilizer, is proposed as an NH3 uptake material through a chemical storage mechanism. The NH4ZnPO4 particles synthesized by a wet mechanochemical method with monoclinic and hexagonal crystal structures can incorporate NH3 molecules and directly transform them into NH4Zn(NH3)PO4 without producing byproducts. The chemical storage mechanism depends on the particle morphology; therefore, the uptake amount per surface area surpasses that of porous materials. NH4ZnPO4 exhibited excellent cycling performance due to its reusability, which is regenerated by releasing NH3 from NH4Zn(NH3)PO4 when heated in air at ≈100 °C. Taking inspiration from previously used and familiar fertilizers further extends this new area of innovative materials that can be used for the reversible storage of low‐molecular‐weight gases.
Unveiling the Critical Role of Pre‐Hydrothermal Effect in Plant Biowaste‐Derived Hard Carbon for Superior Rate Capability and Cycle Life in Sodium‐Ion Batteries
Authors: Ishaq Muhammad , Jabeen Maher , He Yu‐Shi , Che Haiying , Xu Wei , Zhao Shuzhi , Shen Yixing , Li Linsen , Ma Zi‐Feng 
Published: December 2024

AbstractLeveraging economically viable plant bio‐waste‐derived hard carbon (HC) anode materials for sodium‐ion batteries is logical. Many plants' bio‐waste materials are used as HC precursors, but their fabrication process is usually limited by direct carbonization which constrains their large‐scale sustainability. Herein, the critical role of the pre‐hydrothermal carbonization effect in regulating the structure and interfacial Na+ storage mechanism/performance of HC derived from oak leaves (OL) biowaste (OLHC) is reported. The resultant OLHC demonstrates a high‐reversible capacity (378 mAh g−1 at 0.1 C), superior rate performance (272.9 mAh g−1 at 10 C), remarkable cycling performance (75% after 8000 cycles at 10 C), and adequate ICE (85%). Advanced ex/in situ characterization combined with theoretical calculations reveals that hydrothermal pre‐regulation of OLHC stabilizes the spherical particles, introducing more active sites and promoting surface properties with oxygen dopant‐induced defects, which shows uneven surface electrostatic potential and lower activation energy for Na+ adsorption thus generates a thin layer of PF6−/NaF‐enriched core‐shell‐like SEI modulation with organic–inorganic composition. This enables fast interfacial Na+ diffusion kinetics, contributing to high‐capacity retention and stable cycling performance. The studies offer a systematic understanding of the pre‐hydrothermal strategy for the structural design of HC from plant‐leaves‐biowaste with true sustainability and improved performance for SIBs.
Improving Crystallization of Wide‐Bandgap Lead Halide Perovskite for All‐perovskite Tandems
Authors: Du Shengjie , Guo Yaxiong , Wang Chen , Chen Guoyi , Li Guang , Liang Jiwei , Chen Weiqing , Yu Zhiqiu , Ge Yansong , Jia Peng , Guan Hongling , Yu Zixi , Cui Hongsen , Yu Zhenhua , Ke Weijun , Fang Guojia 
Published: December 2024

AbstractWide‐bandgap (WBG) perovskite solar cells (PSCs) are crucial component of tandem solar cells (TSCs). However, the main obstacles currently faced by WBG PSCs are their imperfect crystal quality, leading to large open circuit voltage (VOC) losses and poor stability. The use of 2,5‐dibromothieno[3,2‐B] thiophene (DBrT) as an additive in WBG PSCs enhances crystal quality, mitigates defects, and improves stability by promoting crystal growth and passivating bulk and interface defects. The interaction between Pb─S bonds, π–π stacking, and hydrogen bonding facilitates an ordered molecular arrangement, leading to better crystallization and reduced non‐radiative recombination. Meanwhile, DBrT can also spontaneously diffuse to the grain boundary, thus permeate to top and buried surfaces of perovskite, further passivating defects at the interfaces and reducing non‐radiative recombination. This strategy not only improves energy level alignment and carrier transport but also achieves a champion power conversion efficiency (PCE) of 22.40% for the inverted WBG PSC with a high VOC of 1.27 V. a PCE of 20.39% for semi‐transparent devices, and a high 28.31% PCE for 4‐terminal all‐perovskite tandem solar cells, thereby offering a comprehensive approach to enhancing the performance of WBG and tandem perovskites.
Coherent Conversion Between Single‐Frequency and Ultrafast Lasers
Authors: Zhou Jiaqi , Xiong Yatan , Cheng Zhi , Cao Xinru , Feng Yan 
Published: December 2024

AbstractLasers with high spectral coherence are in high demand for applications requiring high precision. Single frequency (SF) and ultrafast lasers represent two types of highly coherent light sources, each with distinct time‐frequency characteristics. The advent of novel technologies based on electro‐optics and nonlinear optics has bridged the gap between these two types of lasers, enabling coherent conversion between them. This review examines several technologies that enable coherent conversion between SF and ultrafast lasers. The generation of ultrafast pulses by modulation of an SF laser, covering both electro‐optic modulation (EOM) and optic‐optic modulation (OOM) is discussed. With respect to Kerr soliton generation by SF laser‐induced parametric frequency conversion, schemes with and without resonator structure are compared and discussed. The extraction of a single comb line from an ultrafast laser using stimulated Brillouin scattering is also presented. The advent of new technologies using all‐polarization‐maintaining fiber structures has made fiber Brillouin amplification a practical and robust solution for single comb line extraction. These coherent lasers with customizable time and frequency characteristics are poised to become essential building blocks in future photonic technologies.
Pritt, tesa & Co – Examining glue sticks and the chemical equilibrium
Authors: Ducci Matthias 
Published: December 2024

AbstractIm Beitrag wird ein Ausschnitt aus einer Unterrichtseinheit zum Thema Klebstoffe beschrieben. Darin wird u. a. ein einfacher, schulisch relevanter Nachweis für Polyvinylpyrrolidon (PVP, Povidon) in Klebestiften präsentiert. Darüber hinaus werden Eigenschaften des Povidon‐Iod‐Gleichgewichts betrachtet.
Is Mediation a Scientific Discipline? Theoretical and Practical Perspectives
Authors: Blanco Carrasco Marta , Arias Astray Andrés , Ferreira Jorge Manuel Leitão 
Published: December 2024

ABSTRACTThe main objective of this study is to determine whether mediation is regarded as an autonomous discipline from both academic and professional standpoints. To achieve this, the study initially conducted a review of the most recent literature on the subject, followed by gathering opinions from experts, professionals, and trainers across eight different countries through in‐depth interviews and discussion groups. Among the primary findings of the research, it becomes apparent that while mediation remains a relatively underexplored topic, existing literature suggests that it possesses elements to assert its status as a scientific discipline, evidenced by its own axioms, paradigms, models, and methodologies. However, the professionals and experts consulted contend that it falls short of being classified as such. They cite several challenges, including the scarcity of real cases for investigation, the disconnect between theory and professional application, and the need for enhanced quality in scientific research to surmount the stagnation it has encountered for years.
Poor Performance of Applicator Tampon‐Based Self‐Collection for Liquid‐Based Cytology Among Women Attending a Tertiary Hospital in South Africa
Authors: Tiiti Teboho Amelia , Nkwinika Varsetile Varster , Mashishi Tebogo Loraine , Molefi Kgotlaethata Aaron , Msibi Thembeni Lucia , Khaba Moshawa , Bogers Johannes , Lebelo Ramokone Lisbeth 
Published: December 2024

ABSTRACTBackgroundThe South African Cervical Cancer Prevention and Control Policy was updated in June 2017, recommending liquid‐based cytology (LBC) as the preferred screening method and the investigation of self‐sampling for cervical cancer screening.AimTo compare the performance of the Self Collection Cervical Health Screening Kit [SelfCerv (applicator tampon)] to the Cervex‐Brush Combi for cytology screening. The study further aimed to compare high‐risk (hr‐) human papillomavirus (HPV) and LBC test results from both methods.MethodsThe study included 446 paired samples, comprising self‐collected (SelfCerv) and healthcare provider‐collected (Cervex‐Brush Combi) samples from women aged ≥ 18 years attending gynaecology outpatient clinics at a tertiary hospital in Pretoria, South Africa. LBC slides were prepared using the ThinPrep 5000 processor and manually stained with Hematoxylin and Eosin (H&E). Detection of 14 hr‐HPV types was performed using the Abbott RealTime HR‐HPV assay. Statistical analyses were performed using STATA version 17.0 (Stata Corp., College Station, Texas, USA).ResultsA statistically significant difference in cervical cytology detection between the two methods was observed (p = 0.0025). The Cervex‐Brush Combi was more effective in collecting endocervical cells (73.4%; 95% CI: 69.0–77.9) compared to the SelfCerv applicator tampon (7.3%; 95% CI: 4.7–9.9); (p < 0.001). Cytological abnormalities were detected in 65.4% (136/208) of participants who tested positive for hr‐HPV by healthcare provider sampling compared to 40.8% (84/206) by self‐sampling. A fair agreement (κ: 0.35) with a concordance rate of 96.2% (95% CI: 94.4–98.0) was observed for specimen adequacy and diagnosis parameters [κ: 0.34, with a concordance rate of 67.7% (95% CI: 63.2–72.1)] between the two methods.ConclusionThe findings of this study do not support the implementation of applicator tampon‐based self‐collection as a method for cytology‐based cervical cancer screening.
Sustainable Adsorbent: Activated Carbon From Waste Styrofoam for Efficient Aluminum Removal
Authors: Ren Yu Shuang , He Qi , Liao Wanying , Liao Yuxuan , Zhan Zhenchuan , Xu Jiajun , Acioly Thiago Machado da Silva , Viana Diego Carvalho , Ilyas Muhammad 
Published: December 2024

ABSTRACTThis paper reports on batch investigations utilizing activated carbon (AC) made from waste Styrofoam to adsorb aluminum (Al3+) from aqueous solutions. The AC morphology and structure were examined using Fourier‐transform infrared spectroscopy, scanning electron microscopy, and surface area analysis. The factors affecting the performance of adsorption were thoroughly examined. Al3+ removal was found to be maximal, that is, 98.65% using 0.2 g of AC at 90 min in a solution of pH 5 maintained at 60°C. Using a flame‐mode atomic absorption spectrophotometer (AAnalyst 700, PerkinElmer, USA), the quantity of Al3+ in the adsorption solution was measured. For the purpose of studying adsorption, the pseudo‐first‐order, pseudo‐second‐order, Langmuir, Freundlich, Temkin, Jovanovich, and Harkins–Jura isotherms were analyzed. The kinetic study shows that the adsorption of Al3+ onto Al3+ is controlled by pseudo‐second‐order kinetics. It was observed that among these models, the Langmuir model showed the most favorable fit for the equilibrium data on the removal of Al3+ onto AC, with a strong fit (R2 = 0.995). The values of thermodynamic parameters such as entropy (ΔS°), Gibbs free energy (ΔG°), and enthalpy (ΔH°) show that the adsorption process is spontaneous and exothermic in nature. In Al3+ solutions with low concentrations, the AC exhibited a high adsorption rate. In addition, a check of the error function was performed. To find out if the AC could be utilized again after the adsorption procedure, desorption investigations were carried out. Due to its high adsorption capacity (> 98%) and porous structure, the prepared AC shows significant promise as an alternative adsorbent for Al3+. These findings demonstrate that the AC is both effective and efficient in removing Al3+ from wastewater.