The application of a technique to eliminate the latent period during crystallization of sucrose by high intensity ultrasound (HIU) was investigated in this paper. Employing HIU (20 kHz, 750 W) to crystallization of sucrose, latent period was eliminated and it was found to obey first order kinetics (K ∼10s) in the temperature range of 30-50 °C. Employing Arrhenius equation, the average energy of activation (E) estimated as 5.0 kcal mol. Traditional knowledge indicates that crystallization is sufficiently spontaneous; however, the magnitude of "K" and other thermodynamic quantities of the process indicate that crystallization is actually a slow process. Generally, chemical reactions which posses low rate constants, need the high energy of activation. On the contrary, the energy of activation is appreciably less. The energy of activation with a rate constant of the order of 10s could be predicted of the order of 20 kcal mol at 27 °C. The low energy of activation for crystallization of sucrose is of interest. A very interesting elucidation can be had from neutron diffraction data and transport property of the sucrose which is discussed in details in this paper.
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http://dx.doi.org/10.1016/j.ultsonch.2018.05.030 | DOI Listing |
Environ Sci Technol
January 2025
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Pyrogenic carbons (PCs), with varying structures depending on the materials and thermal treatment conditions, have been extensively used to enhance anaerobic digestion by mediating electron transfer. However, the underlying mechanism has yet to be explored. Herein, the redirection and enhancement of the direct interspecies electron transfer (DIET) pathway were evidenced, along with the upregulated electrochemical properties and structural proteins in the methanogenic consortia.
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January 2025
Department of Chemistry, Faculty of Science, Arak University, Arak, 38481-77584, Iran.
In this study, a novel hybrid nanostructure consisting of acid-decorated chitosan and magnetic AlFeO nanoparticles was fabricated. The acid-decorated chitosan provided a stable and biocompatible matrix for the magnetic AlFeO nanoparticles. Various techniques including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction patterns (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), specific surface area (BET), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) were used to characterize and confirm the successful synthesis of the hybrid nanostructure.
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January 2025
Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 2455, 11451, Riyadh, Saudi Arabia.
Polycyclic aromatic compounds (PACs) are pervasive environmental contaminants derived from diverse sources including pyrogenic (e.g., combustion processes), petrogenic (e.
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January 2025
Center for Global Health Research, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India.
In the manufacturing of some sectors, such as marble and brick, certain byproducts, such as sludge, powder, and pieces containing valuable chemical compounds, emerge. Some concrete plants utilize these byproducts as mineralogical additives in Turkey. The objective of the experimental study is to ascertain whether the incorporation of waste from the marble and brick industries, in powder form, into cement manufacturing as a mineralogical additive or substitute is a viable option.
View Article and Find Full Text PDFNat Commun
January 2025
National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing, East China University of Technology, Nanchang, 330013, China.
Piezoelectric catalysis possesses the potential to convert ocean wave energy into and holds broad prospects for extracting uranium from seawater. Herein, the Z-type ZnO@COF heterostructure composite with excellent piezoelectric properties was synthesized through in situ growth of covalent organic frameworks (COFs) on the surface of ZnO and used for efficient uranium extraction. The designed COFs shell enables ZnO with stability, abundant active sites and high-speed electron transport channels.
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