AI Article Synopsis
- In a study of graphene oxide (GO) and poly-N-isopropylamide (PNIPAM) in water, researchers observed a new type of rheological behavior when the material was subjected to small deformations, characterized by an oscillating modulus over long time periods.
- The frequency of these oscillations varied between 100 and several 1000 seconds, influenced by the amount of filler and the method of preparing the samples (either in situ polymerization or blending).
- When exposed to larger deformations (100-300%), the material exhibited a shift from periodic oscillations to rapid recovery, followed by a decrease and eventual increase in its modulus beyond the original value before deformation.
Article Abstract
In a material consisting of graphene oxide or reduced graphene oxide and poly-N-isopropylamide (PNIPAM) in an aqueous solution, a new type of rheological behaviour is found. When subjecting the material to a short and relatively small deformation pulse, the modulus, which is observed by small deformations in the linear-viscoelastic or very slightly nonlinear range, oscillates with periodicities between 100 and several 1000 seconds; however, in many cases, it also increases systematically. The periodicity depends on the filler content and the sample preparation method (in situ polymerisation vs. blending). When subjecting the material to high nonlinear deformations (γ0 = 100-300%), the resulting linear viscoelastic behaviour changes from a periodic oscillation to a quick recovery of the original data, followed by a decrease and a subsequent increase beyond the value of the modulus of the material prior to the deformation pulse.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c4sm02544j | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Hierarchical Porous Aggregate-Enabled Chromatography-Inspired Single-Sensor E-Nose for Volatile Monitoring.
ACS Sens
January 2025
School of Chemistry and Molecular Engineering, In Situ Devices Research Center, Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University, Shanghai 200241, China.
Monitoring volatile organic compounds (VOCs) is crucial for ensuring safety and health. In this study, we introduce a strategy to engineer a chromatography-inspired single-sensor (CISS) e-nose tailored for VOC monitoring. This approach overcomes the limitations of traditional methodologies and conventional e-noses.
View Article and Find Full Text PDFRare-earth oxide promoted Pd electrocatalyst for formic acid oxidation.
Dalton Trans
January 2025
Fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering, College of Chemistry & Materials Science, Fujian Normal University, Fuzhou, Fujian 350007, P. R. China.
The development of Pd-based materials with high activity and long-term stability is crucial for their practical applications as an anode catalyst in direct formic acid fuel cells. Herein, we reveal that the catalytic activity of Pd towards formic acid oxidation can be enhanced by incorporation of a series of rare-earth oxides, including ScO, CeO, LaO, and PrO. For example, Pd nanoparticles incorporated with ScO supported on nitrogen-doped reduced graphene oxide (Pd-ScO/N-rGO-, = 1/3, 1/2, 2/3, 1, and 3/2; "" denotes the molar ratio of Pd : Sc) can be obtained using a sodium borohydride reduction method.
View Article and Find Full Text PDFNanoparticle-protein corona enhances accuracy of Ca-19.9-based pancreatic cancer classification.
Nanoscale
January 2025
Institute of Inorganic Chemistry, Graz University of Technology, 8010 Graz, Austria.
Among the various types of pancreatic cancers, pancreatic ductal adenocarcinoma (PDAC) is the most lethal and aggressive, due to its tendency to metastasize quickly and has a particularly low five-year survival rate. Carbohydrate antigen 19-9 (CA 19-9) is the only biomarker approved by the Food and Drug Administration for PDAC and has been a focal point in diagnostic strategies, but its sensitivity and specificity are not sufficient for early and accurate detection. To address this issue, we introduce a synergistic approach combining CA 19-9 levels with a graphene oxide (GO)-based blood test.
View Article and Find Full Text PDFHigh performance humidity sensor based on a graphene oxide-chitosan composite.
Phys Chem Chem Phys
January 2025
Temperature and Humidity Metrology, CSIR-National Physical Laboratory, Dr K. S. Krishnan Marg, New Delhi, 110012, India.
In this study, we have proposed an advanced humidity sensor based on a composite of chitosan (CS) and graphene oxide (GO), prepared by the drop casting method. Graphene oxide-chitosan (GO-CS) films with varying volumetric ratios, along with pure GO and CS films, were prepared and extensively characterized using XRD, Raman, FTIR, SEM, XPS, and water contact angle to study their structural and morphological properties. Comparative analysis of humidity sensing parameters of all prepared films revealed that the film with a volumetric ratio of 4 : 1 (GOCS-2) performs best among all of them, which is attributed to the synergistic interaction between GO and CS.
View Article and Find Full Text PDFMetal-free photocatalyst with reduced graphene oxide-doped graphitic carbon nitride homojunctions for efficient antibacterial applications.
RSC Adv
January 2025
College of Food Science and Technology, Jiangsu Agri-animal Husbandry Vocational College Taizhou 225300 China
Bacterial infections are a major global health challenge, posing severe risks to human well-being. Although numerous strategies have been developed to combat bacterial pathogens, their practical application is often hindered by operational constraints. Photocatalytic materials have emerged as promising candidates for bacterial disinfection and food preservation due to their efficiency and sustainability.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!