Brownian heat engines use local temperature gradients in asymmetric potentials to move particles against an external force. The energy efficiency of such machines is generally limited by irreversible heat flow carried by particles that make contact with different heat baths. Here we show that, by using a suitably chosen energy filter, electrons can be transferred reversibly between reservoirs that have different temperatures and electrochemical potentials. We apply this result to propose heat engines based on mesoscopic semiconductor ratchets, which can quasistatically operate arbitrarily close to Carnot efficiency.
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http://dx.doi.org/10.1103/PhysRevLett.89.116801 | DOI Listing |
J Colloid Interface Sci
January 2025
College of Light Industry and Food Engineering, Nanjing Forestry University, Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing 210037 China. Electronic address:
Surface-enhanced Raman scattering (SERS) is a highly sensitive technology to detect target analytes. The construction of dynamic "hot-spots" represents a significant approach to enhancing detection sensitivity. Herein, a hybrid plasma platform with dynamic "hot-spots" was developed for SERS recognition based on the assembly of gold nanospheres (AuNSs) on temperature-sensitive bacterial cellulose (BC) film grafted with poly(N-isopropylacrylamide) (PNIPAM).
View Article and Find Full Text PDFClin Neurophysiol
January 2025
Institute for Research and Development on Bioengineering and Bioinformatics (IBB), CONICET-UNER, Oro Verde, Argentina; Center for Rehabilitation Engineering and Neuromuscular and Sensory Research (CIRINS), National University of Entre Ríos (UNER), Oro Verde, Argentina. Electronic address:
Objective: To describe the cortical evoked potentials in response to radiofrequency stimulation (RFEPs) in human volunteers.
Methods: Seventeen healthy volunteers participated in an experimental session in which radiofrequency (RF) and electrical (ES) stimulation were applied to the dorsum of the hands and feet. EEG was recorded to evaluate evoked responses for each stimulus modality and stimulation site.
Anal Chem
January 2025
School of Life Sciences, Key Laboratory of Space Bioscience & Biotechnology, Northwestern Polytechnical University, Xi'an 710072, China.
Lymphoma is a malignant cancer characterized by a rapidly increasing incidence, complex etiology, and lack of obvious early symptoms. Efficient theranostics of lymphoma is of great significance in improving patient outcomes, empowering informed decision-making, and driving medical innovation. Herein, we developed a multifunctional nanoplatform for precise optical imaging and therapy of lymphoma based on a new photosensitizer (1-oxo-1-benzoo[de]anthracene-2,3-dicarbonitrile-triphenylamine (OBADC-TPA)).
View Article and Find Full Text PDFSci Rep
January 2025
Xingtai Naknor Technology Co., Ltd, Xingtai, 054000, China.
The heating oil circuit plays an essential role in the heating calendering roller for the lithium battery pole piece. To achieve the optimization of the heating oil circuit, a fluid-thermal-structural coupling method and a multi-objective optimization procedure are proposed to obtain the optimal solution. A fluid-thermal-structural coupling flowchart based on the numerical modeling for the calendering roller temperature distribution is created to automate the analysis processes in the optimization iteration.
View Article and Find Full Text PDFSci Rep
January 2025
College of Environment and Bioengineering, Henan University of Engineering, Zhengzhou, 451191, China.
This study aims to explore the mechanism behind the influence of stress on gas adsorption by coal during deep mining and improve the accuracy of gas disaster prevention and control. To achieve this aim, thermodynamic analysis was conducted on the process of gas adsorption by loaded coal, and modified thermodynamic model proposed by previous scholars. It is found that stress plays an important role in gas adsorption by coal.
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