Commercially pure nickel was processed by high pressure torsion (HPT) and subjected to ultrasonic treatment (UST) with different amplitudes of compression-tension stresses in the zone of stress antinode of a standing wave. It was found that microstructure parameters such as the dislocation density, low- and high-angle grain boundary fractions, microhardness, and the stored excess energy as well, non-monotonically depend on the ultrasound amplitude. A structure relaxation leading to a reduction of internal stresses and stored energy and increase of the fraction of high-angle boundaries was observed at some intermediate amplitudes of the oscillating stress. The maximum relaxation effect was observed in the samples after UST with the amplitude of 60MPa. Possible mechanisms of the influence of ultrasound on the microstructure of deformed materials are discussed.
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http://dx.doi.org/10.1016/j.ultras.2017.09.005 | DOI Listing |
Ind Eng Chem Res
January 2025
Department of Chemistry, Physics, and Materials Science, Fayetteville State University, Fayetteville, North Carolina 28301, United States.
An efficient Suzuki cross-coupling reaction under continuous flow conditions was developed utilizing an immobilized solid supported catalyst consisting of bimetallic nickel-palladium nanoparticles (Ni-Pd/MWCNTs). In this process, the reactants can be continuously pumped into a catalyst bed at a high flow rate of 0.6 mL/min and the temperature of 130 °C while the Suzuki products are recovered in high steady-state yields for prolonged continuous processing.
View Article and Find Full Text PDFACS Cent Sci
January 2025
Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
Recently, nickel catalysts have garnered considerable attention for their efficacy and versatility in asymmetric catalysis, attributed to their distinctive properties. However, the use of cost-effective and sustainable divalent nickel catalysts in C-H activation/asymmetric alkene insertion poses significant challenges due to the intricate control of stereochemistry in the transformation of the tetracoordinate C-Ni(II) intermediate. Herein, we report a Ni(II)-catalyzed enantioselective C-H/N-H annulation with oxabicyclic alkenes.
View Article and Find Full Text PDFJ Adv Nurs
January 2025
Nursing Science (INS), Department Public Health (DPH), Faculty of Medicine, University of Basel, Basel, Switzerland.
Aim: To implement and evaluate an Advanced Practice Nurse-led transitional care model (AdvantAGE) to reduce rehospitalisation rates in frail older adults discharged from a Swiss geriatric hospital.
Design: The study adopts an effectiveness-implementation hybrid design (Type 1) to simultaneously evaluate the effectiveness of the care model and explore the implementation process.
Methods: The primary outcome, the 90-day rehospitalisation rate, will be evaluated using a matched-cohort design with a prospective intervention group and a retrospective control group.
J Environ Manage
January 2025
Suzhou Botree Cycling Sci & Tech Co., Ltd, Suzhou, Jiangsu, 215000, China.
It is imperative to recover the valuable components of spent HPCs. We have proposed a hydrometallurgical process and recovered 99.9% of V, 99.
View Article and Find Full Text PDFBull Environ Contam Toxicol
January 2025
Sichuan Academy of Eco-Environmental Sciences, Chengdu, 610041, China.
The widespread application of swine-farming wastewater to soil and water is increasingly contributing to heavy metal contamination, posing significant environmental risks. This study investigated the concentrations of eight heavy metals in swine-farming wastewater following different treatment processes, and assessed their ecological risks in Sichuan Province, China. The findings revealed that zinc, copper and nickel exhibited the highest concentrations, potentially causing heavy or strong contamination levels and leading to heavy or slight ecological risks.
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