Wearable thermoelectric devices offer a transformative approach to energy harvesting, providing sustainable solutions for powering next-generation technologies. In pursuit of efficient, flexible, biocompatible, and cost-effective thermoelectric materials, zinc oxide (ZnO) has emerged as a distinctive candidate due to its unique combination of favorable properties. This study explores the growth and optimization of ZnO nanorods on conductive carbon fabric (CF) using a simple microwave-assisted solvothermal technique. This method circumvents traditional complex processes that typically involve high temperatures or lengthy growth times, offering advantages such as rapid, uniform, and controllable volumetric heating. By systematically varying growth parameters, including microwave power and reaction time, we established conditions that promote the vertical alignment of ZnO nanorods, essential for enhancing thermoelectric performance. Structural and morphological analyses highlight the pivotal influence of the seed layer and growth parameters in achieving dense, uniform growth of ZnO nanorods. Interestingly, at higher microwave power levels, a transformation from nanorod structures to sheetlike morphologies was observed, likely due to Ostwald ripening, where larger particles grow at the expense of smaller ones. The optimized growth conditions for achieving superior growth and thermoelectric performance were identified as 15 min of growth at 100 W microwave power. Under these conditions, ZnO nanorods exhibited enhanced crystallinity and a higher growth rate, contributing to an improved thermoelectric power factor of 777 nW/mK2 at 373 K. This work underscores the importance of precise parameter control in tailoring ZnO nanostructures for wearable thermoelectric applications and demonstrates the potential of scalable, low-cost methods to achieve high-performance energy-harvesting materials.
인류는 역사적으로 삶의 본질을 이해하고 지속적인 충만함을 성취하기 위해 끊임없이 노력해 왔다. 이러한 여정은 종종 자기실현으로 귀결된다. 자기실현은 단순한 심리적 상태를 넘어, 인간의 본질적인 욕구이자 지속적인 성장과 변형, 그리고 진정한 잠재력의 실현을 의미한다. 저명한 브라질 작가 파울로 코엘료는 그의 소설에 서 인간의 경험을 중심에 두며, 존재의 영적이고 실존적인 측면을 탐구한다. 코엘료의 이야기 속 주인공들은 전통적인 서사 속 영웅이 아닌, 평범하지만 내면의 여정을 통해 특별함을 보여주는 인물들이다. 연금술사(1988)의 산티아고와 11분(2003)의 마리 아는 모두 매우 개인적인 여정을 떠나며, 사회적 기대와 내면의 제약에 도전해 자기 안에 숨겨진 보물을 찾아 나선다. 산티아고는 자신의 ‘개인적 전설’을 향한 열망에 의 해 움직이며, 마리아는 사랑과 자존감, 인간관계의 복잡성을 탐색한다. 이 두 인물은 회복력, 용기, 자기 발견의 변혁적 본질을 구현하며, 이 논문은 그들이 자기실현에 이 르는 과정을 분석한다. 이를 통해 코엘료 작품 전반에 흐르는 운명, 삶의 목적, 내면의 충족이라는 보편적 주제를 조명한다. 코엘료는 이러한 이야기들을 통해 개인이 어떻게 자신의 여정을 통해 의미와 자기 실현을 향해 나아갈 수 있는지를 깊이 있게 통찰한다.
본 논문은 윌리엄 깁슨의 뉴로맨서에서 시뮬라크라, 사이버스페이스, 하이퍼리얼리티의 상호작용을 탐구하며, 이 소설을 포스트모던 조건을 집약한 기념비 적 텍스트로 위치시킨다. 장 보드리야르, 장프랑수아 리오타르, 프레드릭 제임슨 등의 이론적 관점을 바탕으로, 깁슨이 현실과 시뮬레이션의 경계가 무의미해진 허구적 우주 를 어떻게 구축하는지를 살핀다. 뉴로맨서에서 사이버스페이스 매트릭스는 단순한 서사 배경을 넘어서, 기호가 현실을 앞서고 대체하는 상징적 영역으로 기능하며 보드 리야르의 하이퍼리얼 개념을 구현한다. 주인공 케이스가 가상 네트워크를 무형으로 탐 색하는 모습은 정체성 위기를 반영하며, 첨단 기술 환경에서 안정된 자아가 붕괴하는 양상을 드러낸다. 본 논문은 이 소설이 데이터 과잉, 미디어 융합, 대서사의 붕괴로 특징지어지는 포스트모던성의 감각적·심리적 분위기를 포착하고 있음을 주장하며, 이 를 통해 현대 디지털 문화를 이해하는 분석적 틀을 제공한다. 정밀한 텍스트 분석을 통해, 이 연구는 뉴로맨서가 사이버펑크 미학에 기여한 바와 미디어 이론, 포스트모 던 철학, 기술문화 연구에서의 관련성을 강조한다.
The use of aluminum-based hybrid metal matrix composite (HMMC) materials, especially in engine components like pistons, is intended to improve wear resistance and overall performance. Crucial tribological indicators, such as wear and friction coefficients, underscore the significance of these materials. However, present aluminum alloys have limited wear because of clustered reinforced particles and relatively high coefficients of thermal expansion (CTE), resulting in inadequate anti-seizure properties during dry sliding conditions. This research introduces a novel “Hybrid Metal Matrix Composite of Al7068 Reinforced with Fly Ash-SiC-Al2O3”. Al7068 is employed for its superior strength-to-weight ratio and specific modulus, which is ideal for components exposed to cyclic loads and varying temperatures. The integration of fly Ash (FA), silicon carbide (SiC), and alumina (Al2O3) as reinforcements enhances wear resistance, diminishes particle clustering, improves stiffness, mitigates CTE discrepancies, and fortifies the composite against strain and corrosion, thereby enhancing its overall performance. The Stir-casting method was used with optimized reinforcement percentages (10 % total), and comprehensive evaluations through wear tests and mechanical property analyses determined the composite's optimal composition. The proposed HMMC variant with the most suitable reinforcement percentage exhibited enhanced engine piston functionality, reduced wear, low deformation of 0.20 mm, and a comparatively higher ultimate tensile strength of 190 megapascals (Mpa).
Quantum dot nanocomposite-based luminescent materials have gained attention for solid-state lighting and optical displays. This study presents a one-step, eco-friendly hydrothermal process to synthesize nitrogen, potassium, and calcium-doped carbon quantum dots (N, K, Ca-doped CQDs) from the flower extract of Mesembryanthemum crystallinum L. (ice plant). The CQDs were characterized using HRTEM, EDX, SAED, XPS, XRD, NMR, FTIR, zeta potential, UV–Vis, and photoluminescence spectroscopy. HRTEM revealed an average particle size of 4.6 nm, with a range of 2 to 7 nm. The CQDs exhibited a quantum yield of 20%, excellent water solubility, photostability, and greenish fluorescence under UV (365 nm). The fluorescence spectra were analyzed using CIE (Commission Internationale de l’Eclairage) chromaticity coordinates to determine the emitted color. The fluorescence emission behavior was influenced by solvent polarity, locally excited (LE) states, intramolecular charge transfer (ICT) processes, and hydrogen bonding. The hydrogen bonds between N, K, Ca-doped CQDs and DI water likely enhanced the stability of the ICT state, resulting in a red shift in fluorescence. Additionally, we developed an eco-friendly wheat-starch-based bioplastic nanocomposite by embedding the CQDs. The effects of CQD concentration and pH sensitivity on luminescent properties were explored. Finally, we demonstrated a practical application by designing a conceptual nameplate-like calligraphy using the optimized CQDs@bioplastic nanocomposite film (CQD concentration: 240 mg/mL, pH: 2.7), highlighting its potential for luminescent film applications.
This study incorporates the formation of carbon quantum dots (CQDs) via a hydrothermal approach, recording the first-time use of castor leaves as a natural precursor. The used precursor offers various benefits including novelty, abundance, elemental composition, and biocompatibility. CQDs were further characterized with multiple techniques including high-resolution transmission electron microscope (HR-TEM), X-ray photoelectron microscopy (XPS), X-ray diffraction (XRD), Fouriertransform infrared spectroscopy (FTIR), Raman spectroscopy, UV–visible spectroscopy, Zeta analysis, and optical spectroscopy. They are fundamentally composed of carbon (71.37%), nitrogen (3.91%), and oxygen (24.73%) and are nearly spherical, and uniformly distributed with an average diameter of 2.7 nm. They possess numerous interesting characteristics like broad excitation/emission bands, excitation-sensitive emission, marvelous photostability, reactivity, thermo-sensitivity, etc. A temperature sensor (thermal sensitivity of 0.58% C− 1) with repeatability and reversibility of results is also demonstrated. Additionally, they were found selective and sensitive to ions in aqueous solutions. So, they are also utilized as a fluorescent probe for metal ion ( Fe3+) sensing. The lowest limit of detection (LOD) value for the current metal ion sensor is 19.1 μM/L.
The current standard treatment regimen for patients with cervical cancer consists of a combination of radiotherapy and chemotherapy. However, the serious side effects often encountered with chemotherapy drugs greatly limits the effective doses that can be delivered, and hence the treatment of cervical cancer still faces strong challenges. In this study, carbon nanodots, nanodrugs with anti-cervical cancer activity and with negligible toxicity, were prepared from the precursor herbal extract ginsenoside Rg1. The surface of the Rg1 carbon nanodots is rich in hydrophilic functional groups, resulting in good dispersion in aqueous media and high biocompatibility. In Vitro experiments show that the Rg1 carbon nanodots have significant cytostatic and pro-apoptotic effects on HeLa cells, and could inhibit their migration and invasion. Experiments in tumor-bearing nude mice show that the Rg1 carbon nanodots could significantly inhibit tumor growth. Through qPCR validation, the Rg1 carbon nanodots were shown to enhance HeLa cell apoptosis, by regulating the expression levels of Cyto c, Caspase-9, Caspase-3, Bax, and Bcl-2, induce G2/M phase arrest by regulating CDK 1 and Cyclin B1 expression, and inhibit tumor cell migration by modulating CDH1 and β-catenin. Since the precursor Rg1 is a natural herbal extract, negligible toxic side effects were observed in nude mice. The work demonstrates that Rg1 carbon nanodots can be expected to become a potential nanomedicine against human cervical cancer with negligible toxic side effects and excellent therapeutic effects.
The accurate detection of vital biomarkers such as Ascorbic Acid (AA), Uric Acid (UA) and Nitrite ( NO2 −) is crucial for human health surveillance. However, existing methods often struggle with concurrent detection and quantification of multiple species, highlighting the need for a more effective solution. To address this challenge, this study aimed to develop a multifunctional electrochemical sensor capable of parallel detection of AA, UA and NO2 − using a synergistic combination of Graphene Oxide (GO) and Cadmium Sulfide (CdS) materials. Notably, the fabricated CdS@GO/Glassy Carbon Electrode (GCE) exhibited exceptional electrochemical activity, as evidenced by Differential Pulse Voltammetry (DPV) analysis. The sensor demonstrated remarkable sensitivity (8.13, 10.12, and 9.05 μA·μM−1·cm−2) and ultra-low detection limits (0.034, 0.062, and 0.084 μM) for AA, UA and NO2 −, respectively. Furthermore, it successfully identified single molecules of each analyte in aqueous and biologic fluid samples, with recovery values comparable to those obtained using High-Performance Liquid Chromatography (HPLC) standard addition methods. The significance of this study lies in developing a novel CdS@ GO/GCE sensor that enables concurrent detection and quantification of multiple vital biomarkers, offering a promising tool for human health monitoring and diagnosis.
본 연구 논문은 우파마뉴 채터지의 소설 영어, 8월를 통해 도시 인도 생활을 분석한다. 이 소설은 인도 사회, 관료제, 문화적 역학을 탐구하며, 도시 현실을 복합적으로 조망한다. 주인공의 삶을 분석함으로써 현대 인도 사회를 지배하는 긴장, 모순, 그리고 열망을 밝혀낸다. 주요 주제는 관료제, 문화적 갈등, 사회적 불평등, 정체성, 그리고 도시 맥락에서의 실존적 위기이다. 본 연구는 도시의 복잡성을 이해하고, 포스트식민지 인도의 삶을 형성하는 사회적·문화적·제도적 역학에 대한 통찰을 제공하 는 것을 목표로 한다.
In recent years, high-entropy alloys (HEAs) have attracted considerable attention in materials engineering due to their unique phase stability and mechanical properties compared to conventional alloys. Since the inception of HEAs, CoCrFeMnNi alloys have been widely investigated due to their outstanding strength and fracture toughness at cryogenic temperatures. However, their lower yield strength at room temperature limits their structural applications. The mechanical properties of HEAs are greatly influenced by their processing methods and microstructural features. Unlike traditional melting techniques, powder metallurgy (PM) provides a unique opportunity to produce HEAs with nanocrystalline structures and uniform compositions. The current review explores recent advances in optimizing the microstructural characteristics in CoCrFeMnNi HEAs by using PM techniques to improve mechanical performance. The most promising strategies include grain refinement, dispersion strengthening, and the development of heterogeneous microstructures (e.g., harmonic, bimodal, and multi-metal lamellar structures). Thermomechanical treatments along with additive manufacturing techniques are also summarized. Additionally, the review addresses current challenges and suggests future research directions for designing advanced HEAs through PM techniques.
필립 풀먼(Philip Pullman)의 황금 나침반은 판타지와 디스토피아를 결합하여 상상력을 전체주의에 맞서는 힘으로 탐구한다. 소설의 중심에는 전체주의적 교회를 무너뜨리려는 라이라(Lyra)의 여정이 있으며, 이는 저항을 상징한다. 영혼의 화 신인 다이몬(daemons), 사랑과 의식을 상징하는 먼지 입자(dust) 등과 같은 환상적 장치들은 작품을 풍부하게 만들며, 억압에 맞서는 인간 정신의 반항을 은유적으로 묘사 한다. 풀먼의 소설은 청소년 디스토피아 소설의 보다 광범위한 주제와 공명하며, 급속 한 기술 및 생명공학 발전에 대한 불안감을 포착한다. 이 비평의 핵심은 풀먼의 허구 적 세계가 현대의 문제들을 어떻게 반영하고, 젊은 주인공들의 정의와 공정함을 향한 여정을 통해 상징적으로 해결하고 있는지를 조명하는 데 있다.
Artificial photosynthesis, which mimics the natural process used by plants, offers a promising strategy for harnessing solar energy to produce valuable fuels. One intriguing approach is the photocatalyst-enzyme attached system, where a photocatalyst captures light energy and transfers it to an enzyme to drive specific chemical reactions. This study describes the synthesis of a novel photocatalyst (MWCNTCEBr) formed by coupling multiwall carbon nanotubes (MWCNTs) with a dye ethidium bromide (EBr) via a condensation reaction. The resulting photocatalyst exhibits excellent charge separation and migration abilities, leading to enhanced photocatalytic activity. Notably, MWCNTCEBr photocatalyst successfully converts α-Ketoglutarate to L-Glutamate (81.9%) and photo-regeneration of NADH (76.20%) under the influence of solar radiation. Therefore, the study demonstrates the development and the application of MWCNTCEBr photocatalyst for impressive NADH regeneration and bio-transformation.
This article describes an efficient electrochemical sensor based on a graphene oxide- manganese dioxide (GO-MnO2) nanocomposite for detecting acetaminophen (AAP) in human fluids. The MnO2- wrapped GO sensing element was prepared by a simple and environmentally friendly co-precipitation method. The prepared GO-MnO2 nanostructure was characterized for its structural, morphological, and functional properties and tested for AAP detection. At a pH of 3, the electrochemical results revealed a high redox process toward AAP due to the transfer of two electrons and protons between the GO-MnO2/ glassy carbon electrode (GO-MnO2/GCE) and AAP. The differential pulse voltammetry (DPV) analytical results showed the precise sensing ability of AAP in a wide linear range [0.125–2000 μM] with superior anti-interference ability. The calculated sensitivity of the GO-MnO2/GCE was 17.04 μAμM−1 cm− 2, and the detection limit (LOD) was 7.042 nM. The sensor exhibited high reliability, good reproducibility, and a good recovery range of 98.47–99.22% in human urine sample analysis.
High-entropy alloys (HEAs) represent a revolutionary class of materials characterized by their multi-principal element compositions and exceptional mechanical properties. Powder metallurgy, a versatile and cost-effective manufacturing process, offers significant advantages for the development of HEAs, including precise control over their composition, microstructure, and mechanical properties. This review explores innovative approaches integrating powder metallurgy techniques in the synthesis and optimization of HEAs. Key advances in powder production, sintering methods, and additive manufacturing are examined, highlighting their roles in improving the performance, advancement, and applicability of HEAs. The review also discusses the mechanical properties, potential industrial applications, and future trends in the field, providing a comprehensive overview of the current state and future prospects of HEA development using powder metallurgy.