Measurements of particle flows driven by temperature gradients are conducted as a function of temperature on aqueous suspensions of polystyrene nanoparticles and proteins of T4 lysozyme and mutant variants of T4 lysozyme. The thermodiffusion coefficients are measured using a microfluidic beam deflection technique on suspensions with particle concentrations on the order of 1 vol %. At T < or ~ 20 degrees C, all of the nanoparticles studied migrate to the hot regions of the fluid; i.e., the thermodiffusion coefficient is negative. At higher temperature, T > or ~ 50 degrees C, the thermodiffusion coefficient is positive with a value consistent with the predictions of a theoretical model originally proposed by Derjaguin that is based on the enthalpy changes due to polarization of water molecules in the double layer.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/la700489e | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
SNaP-C: Development of a Silver Nanoparticle Antioxidant Assay for the Selective Quantitative Analysis of Vitamin C in Beverages.
ACS Omega
January 2025
Department of Chemistry and Biochemistry, University of Colorado Colorado Springs, 1420 Austin Bluffs Parkway, Colorado Springs, Colorado 80918 United States.
The development of a sensitive and selective silver nanoparticle assay for the quantitation of vitamin C (SNaP-C), as ascorbic acid (AA) and total ascorbic acid (TAA = AA + dehydroascorbic acid, DHAA), is described. Three assay parameters were investigated and optimized: (1) synthesis of silver nanoparticles (AgNPs) to produce a reliable enhanced localized surface plasmon resonance (LSPR) in the presence of specific added antioxidants; (2) ensuring long-term stability of AA and DHAA in aqueous solutions; and (3) SNaP-C assay conditions to allow for rapid analysis of samples (beverages) by monitoring the enhanced LSPR. The synthesis of AgNPs using soluble starch as a capping agent and d-arabinose as a reducing agent was optimized in a CEM Discover SP laboratory microwave.
View Article and Find Full Text PDFSynthesis of P(AM/AA/SSS/DMAAC-16) and Studying Its Performance as a Fracturing Thickener in Oilfields.
Polymers (Basel)
January 2025
Engineering Research Center of Oil and Gas Field Chemistry, Universities of Shaanxi Provence, Xi'an Shiyou University, Xi'an 710065, China.
In order to solve the problems of long dissolution and preparation time, cumbersome preparation, and easy moisture absorption and deterioration during storage or transportation, acrylamide (AM), acrylic acid (AA), sodium p-styrene sulfonate (SSS), and cetyl dimethylallyl ammonium chloride (DMAAC-16) were selected as raw materials, and the emulsion thickener P(AM/AA/SSS), which can be instantly dissolved in water and rapidly thickened, was prepared by the reversed-phase emulsion polymerization method. DMAAC-16, the influence of emulsifier dosage, oil-water ratio, monomer molar ratio, monomer dosage, aqueous pH, initiator dosage, reaction temperature, reaction time, and other factors on the experiment was explored by a single-factor experiment, and the optimal process was determined as follows: the oil-water volume ratio was 0.4, the emulsifier dosage was 7% of the oil phase mass, the initiator dosage was 0.
View Article and Find Full Text PDFCross-Linked Self-Standing Graphene Oxide Membranes: A Pathway to Scalable Applications in Separation Technologies.
Membranes (Basel)
January 2025
Centre for Advanced 2D Materials, National University of Singapore, Singapore 117546, Singapore.
The large-scale implementation of 2D material-based membranes is hindered by mechanical stability and mass transport control challenges. This work describes the fabrication, characterisation, and testing of self-standing graphene oxide (GO) membranes cross-linked with oxides such as FeO, AlO, CaSO, NbO, and a carbide, SiC. These cross-linking agents enhance the mechanical stability of the membranes and modulate their mass transport properties.
View Article and Find Full Text PDFReactive template method for synthesis of water-soluble fluorescent silver nanoclusters supported on the surface of cellulose nanofibers.
Carbohydr Polym
March 2025
Plant Fiber Material Science Research Center, State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Engineering, South China University of Technology, Guangzhou 510640, China.
There is an emerging quest for fabrication of water-soluble fluorescent silver nanoclusters (AgNCs) with long-lasting fluorescent properties and dimensional stability while being sustainable and functional. Thus, a well-known seed-mediated growth strategy has been developed to manufacture AgNCs supported onto carboxyl and aldehyde modified cellulose nanofiber (DATCNF) with ultra-small and intense fluorescence. The DATCNF acts as a reductant, template, and stabilizer while the protective ligand, 2-Mercaptonicotinic Acid (2-HMA), provides AgNCs with luminous characteristic and constrained size of 4.
View Article and Find Full Text PDFInvestigating the interactions between a poloxamer and TEMPO-oxidised cellulose nanocrystals.
Carbohydr Polym
March 2025
Bristol Composites Institute, School of Civil, Aerospace, and Design Engineering, University of Bristol, University Walk, Bristol BS8 1TR, UK. Electronic address:
Cellulose nanocrystals (CNCs) have emerged as promising, sustainable materials, with applications in sensors, coatings, pharmaceuticals, and composites. Their modification with block copolymers such as PEO-PPO-PEO triblock copolymers of the Pluronic family has been attempted many times in the literature, with claims that such modification would happen by an anchor(PEO)-buoy(PPO)-anchor(PEO) mechanism. However, there is much disagreement in the literature on this.
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!