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Microwave-fluidic continuous manufacturing of ultrasmall silver nanoparticles in a polycaprolactone matrix as antibacterial coatings
No full textFast, energy-efficient, and continuous manufacturing of nanoparticles (NPs) with controlled size and distribution in polymer matrices is challenging. Herein, a microwave-powered dual-injection continuous flow reactor is presented to prepare silver NP (AgNP)/polycaprolactone (PCL) nanocomposites (AgNP/PCL NCs). Ultrasmall spherical AgNPs (US-AgNPs, 1.86 ± 0.77 nm) can be manufactured in the PCL matrix in less than 3 min at ∼35 °C by applying 60 W microwave power and a combined flow rate of 1.25:1.25 mL/min (Pump1:Pump2). The effect of NP size and amount on the thermal, optical, and antimicrobial properties and the crystallinity of NCs are discussed. The NC crystallinity is independent of the NP’s size and amount, while the NC film roughness is highly dependent on NP size. The antibacterial activity of the US-AgNPs-containing NC toward Escherichia coli (∼98.2%), Pseudomonas aeruginosa (∼98.2%), and Staphylococcus aureus (∼99.1%) is higher than big AgNP-containing NCs (82.3%, 85.7%, and 92.3%, respectively), signifying a strong NP size dependency instead of Ag concentration
Amphiphilic functional polymers as polypropylene nonwoven surface treatment
Get PDFPolypropylene nonwovens (PP NWs) are utilized commonly in baby diapers, adult incontinence products, feminine hygiene items, and wet wipes. Due to the inherent hydrophobic character of these NWs, their properties are significantly influenced by hydrophilic surface treatments to enhance both their performance and the user experience. Although polymer-based formulations offer great versatility, small molecule applications are more prominent in industry. This study proposes an amphiphilic functional polymer-based surface treatment for NW disposable hygiene products. Such polymer offers odor control, enzymatic inhibition, pH control, controlled release of active agents, and antimicrobial activity. This article discusses the synthesis of the as-utilized polymer, succinylated Poly(2-propyl-2-oxazoline-co-ethyleneimine) (S-PPrOZ-PEI), and its characterization by both Fourier-Transform Infrared Spectroscopy (FTIR) and Nuclear magnetic resonance (NMR). Additionally, the preparation of a dilute polymer-based aqueous formulation, and its utilization as a surface treatment to PP NWs are described here. S-PPrOZ-PEI modifies the PP NW surface through its hydrophobic interactions with PP and makes the surface more hydrophilic due to the presence of acid functional groups in its structure. The performance of the applied formulation is evaluated through contact angle measurements, and then they are compared to commercial small-molecule-based surface treatment formulations, which are found to be similar
Enhancement in the performance of a vanadium-manganese redox flow battery using electrospun carbon metal-based electrode catalysts
No full textThis study investigates the performance of both a vanadium/manganese redox flow battery (V/Mn RFB) and an all-vanadium redox flow battery (VRFB), employing carbon metal fabrics (CMFs) prepared through electrospinning followed by carbonization. Noteworthy advancements are observed in both systems upon coupling CMFs with thermally treated graphite felt (GF) electrodes. Nearly doubled peak power density and 50 % higher capacity utilization over 150 charge/discharge cycles at 75 mA cm−2 are achieved for the V/Mn RFB with the incorporation of CMFs alongside graphite felt as catalysts. The VRFB demonstrates notable enhancements too, achieving approximately 200 cycles at a current density of 80 mA cm−2, with high efficiencies (85 %) and electrolyte utilization (79 %) when CMFs are used in combination with graphite felts. These advancements may facilitate pilot-scale testing and integration of the V/Mn RFB for the employment in the renewable energy storage sector and grid-balancing studies
A switched full duplex MIMO architecture with digital linear and nonlinear cancellation
No full textEnabling full duplex (FD) in MIMO systems is challenging due to increased hardware complexity and increased training overhead required for canceling not only self-interference (SI) but also cross-link-interference (CLI) signals, considering both linear and nonlinear effects on each stream. In this paper, we propose switched FD MIMO (FD-SW-MIMO) architecture as a low-complexity, low-overhead solution, which enables stream-based nonlinear estimation to be performed independently from channel estimation, so that those nonlinear reference signals are fed to linear SI and CLI cancellation stages. For improved performance at high transmit power levels, the Random Fourier Features - Least Mean Squares (RFF-LMS) algorithm is employed on the residual SI and CLI signals per stream. Our experiments conducted on a software-defined radio based 2x2 FD MIMO test setup reveal that the proposed FD-SW-MIMO architecture can provide up to 12 dB enhancement over linear only digital cancellation. The proposed architecture requires only minor hardware modification(s), avoiding active analog cancellation circuitry and extra Tx/Rx chains. Requiring the same training overhead as linear only cancellation, FD-SW-MIMO architecture can quadruple the rate of HD SISO for low to moderate transmit power levels, and for high transmit power levels, the HD SISO rate is tripled due to slightly increased overhead
Investigating middle school students' eye movements on the mathematical representations: an eye-tracking study
No full textIn mathematics education, representations are used in place of mathematical structures, ideas, or relationships to concretize, transform, and represent them. When students interact with these representations, they engage in various cognitive activities such as thinking, reasoning, understanding, remembering, problem-solving, attention, and decision-making, which are difficult to observe. Therefore, uncovering these cognitive activities is very significant for mathematics education. However, they are not easy to uncover as they cannot be directly observed. Eye tracking is an important approach that can be used to reveal cognitive activities that cannot be directly observed. This study investigated how middle school students examine representations by examining their eye movements. Eighty-five (40 girls and 45 boys) 7th-grade middle school students participated in the study. In the study, gaze durations, fixation count, and fixation duration on four different representation types: verbal representation, symbolic representation, number line representation, and counters representation were compared. The findings showed that students fixated more on the verbal representation and gazed at it for longer. However, fixation durations on the verbal representation were quite short compared to the other representations. In contrast, when examining the counters, there were fewer fixations and shorter gaze durations, but fixation durations were longer. Gazes on the number line and symbolic representation did not differ across all three variables. The findings indicated that gaze on verbal and non-verbal representations differed to some extent, but not entirely. Finally, the findings are discussed in the context of mathematical representation and eye-tracking literature
A classification of planes intersecting the Veronese surface over finite fields of even order
No full textIn this paper we contribute towards the classification of partially symmetric tensors in Fq3⊗S2Fq3, q even, by classifying planes which intersect the Veronese surface V(Fq) in at least one point, under the action of K≤ PGL (6 , q) , K≅ PGL (3 , q) , stabilising the Veronese surface. We also determine a complete set of geometric and combinatorial invariants for each of the orbits
Fabrication of Cu2O plated carbon fabrics via electrochemical deposition method
No full textFunctional fabrics have many advanced applications to meet the expectations of the end-user industry. There is a variety of approaches to impart functional properties to the fabrics including coatings, the addition of functional fillers, surface modifications, etc. Metallization techniques are also a good candidate to impart functionalities to textile fabrics. On the other hand, Cu2O is a diamagnetic solid that has a variety of applications from flexible electronics to gas sensing. In this study, one of the simplest plating techniques, the electroplating method, was applied to carbon fabric to provide Cu2O coating on the surface which can add the advantages of metal oxides on carbon fabric. The Cu2O particles were observed on the surface of carbon fabric using SEM and the elemental composition of the surface was investigated using the EDS method. The crystal structure of the coating was identified using the X-ray diffraction technique and Raman spectroscopy. To confirm the achieved structure, FTIR analysis was performed as well. The newly fabricated structure can be a promising candidate for supercapacitors, electromagnetic shielding materials, dielectric surfaces, etc
Crafting Compendiums, Making Law: Ottoman Legal Compendiums And The Reconfiguration Of Legal Authority In The Seventeenth Century
Get PDFThis study examines a late seventeenth-century Ottoman legal compendium (kânunmecmûası) comprising kânuns, fatwas, decrees, and excerpts from provincialkânunnâmes. Through an analysis of three manuscript copies—Manisa 5819, SarajevoOriental Institute R.3, and Istanbul Laleli 1263—it delineates a three-stageprocess of compendium-making: formation, expansion, and consolidation, with eachstage executed by a principal actor, respectively, author-compiler, glossator, andcopyist. This study discusses how textual variations across copies reflect active intellectualengagement rather than mechanical reproduction. It shows that marginalannotations, later integrated into the main text, reveal a dynamic process of legalknowledge production shaped by members of the learned hierarchy (ilmiye). Bytracing the accretion of marginalia across the three copies, the study demonstrateshow compendiums functioned as platforms for articulating and debating legal knowledge,particularly through the interaction between kânun and fatwa discourses. Theact of compendium-making reflects a distinct form of kânun consciousness amongscholar-bureaucrats, and it culminated in the development of the Ottoman fatwa asan official statement of law. This study ultimately argues that the legal compendiumemerged as a major legal genre that played a key role in shaping lawmaking beyondthe sultan’s chancery in the seventeenth century
Lost In Pronunciatıon: The Influence Of Sociolinguistic Cues On Truth Judgements
Get PDFAccent strongly shapes social perception, yet mechanisms driving accent-based biasare unclear. Focusing on truthfulness judgements, this thesis examined three competingtheoretical explanations: (1) standard language ideology, which posits thatstandard-accented speakers are granted higher credibility due to institutional prestige;(2) accent-based stereotyping, which suggests that accent evaluations reflectthe perceived status of associated ethnic or social groups; and (3) processing fluency,which argues that harder-to-understand accents trigger negative evaluations due toincreased cognitive effort. This study tested one hundred and thirty-seven Turkishadults who listened to personal anecdotes from four types of Turkish speakers: (1)standard accented, (2) standard-accented with low audio quality, (3) high-statusnon-standard, and (4) low-status non-standard. After each recording, participantsrated the perceived warmth, competence, and truthfulness of the speaker. Themodel based on standard language ideology best explained truth judgments. Unexpectedly,however, non-standard-accented speakers were rated as more truthful thanstandard-accented ones. Mediation analysis indicated that this effect was driven byhigher warmth attributions, even though competence ratings were lower. This studyoffers novel insights into how accent standardness structures social judgments, revealingthe nuanced nature of accent-based stereoty
Efficient Resource Orchestration For Distributed Large Language Model Inference At The Edge
Get PDFThe increasing deployment of Large Language Models (LLMs) in real-time andresource-constrained environments has exposed critical limitations of centralizedcloud inference, including high latency, cost, and scalability concerns. This thesisaddresses these challenges by proposing two integrated solutions for efficient and fairdistributed LLM inference at the edge: the Fair Cost-Efficient Incentive Mechanism(FCIM) and the Adaptive Dynamic Scheduling Algorithm (ADSA). FCIM introducesan auction-based layer allocation framework that ensures truthful participation andfairness among heterogeneous devices, dynamically balancing task latency, rewardcost, memory feasibility, and system-wide alignment. ADSA complements FCIM byscheduling layer execution in a deadline-aware and preemption-conscious manner,reducing queuing delay while adapting to fluctuating device availability and networkconditions.Together, FCIM and ADSA offer a scalable, incentive-compatible, and resourceefficientapproach for edge-based inference. The mechanisms are extensively evaluatedthrough simulations across diverse model architectures, including GPT-Neo,GPT-3, and BLOOM, under varying GPU configurations and bidding scenarios. Resultsdemonstrate that FCIM reduces communication overhead by up to 54.7% andtask processing time by 36.9%, while ADSA decreases queuing delays by 39% comparedto conventional schedulers. Fairness is quantitatively validated using Jain’sindex over both reward and layer distributions, with FCIM consistently outperformingbaseline methods. This thesis establishes a principled foundation for deploying LLMs in federated, latency-sensitive environments and offers insights into futureextensions involving reinforcement learning, multi-tenant inference, and real-worldedge deployments