Effect of sequential addition of precursor in synthesis of Ag-Cu nanoparticles

SummaryThe platelet aggregating activity of extracts of different layers of the arterial wall was compared to that of Achilles tendon. Arterial media and tendon extracts, adjusted to equivalent protein content as an index of concentration, aggregated platelets to the same extent but an arterial intima extract did not aggregate platelets. Platelet aggregation induced by collagen could be inhibited by mixing with intima extract, but only to a maximum of about 80%. Pre-mixing adenosine diphosphate (ADP) with intima extracts diminished the platelet aggregation activity of the ADP. Depending on the relationship between ADP and intima extract concentrations aggregating activity could either be completely inhibited or inhibition abolished. Incubation of ADP with intima extract and subsequent separation of degradation products by paper chromatography, demonstrated a time-dependent breakdown of ADP with AMP, adenosine, inosine and hypoxanthine as metabolic products; ADP removal was complete. Collagen, thrombin and adrenaline aggregate platelets mainly by endogenous ADP of the release reaction. Results of experiments comparing inhibition of aggregation caused by premixing aggregating agent with intima extract, before exposure to platelets, and the sequential addition of first the intima extract and then aggregating agent to platelets, suggest that the inhibitory effect of intima extract results from ADP breakdown. It is suggested that this ADP degradation by intima extract may play a protective role in vivo by limiting the size of platelet aggregates forming at the site of minimal “wear and tear” vascular trauma.

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Modulation in Ru and Cu nanoparticles contents over CuAlPO-5 in synergistic enhancement in the selective reduction and oxidation of biomass-derived furan based alcohols and carbonyls

Catalysis Science & Technology ◽

10.1039/d1cy00593f ◽

2021 ◽

Author(s):

Abhinav Kumar ◽

Rajaram Bal ◽

Rajendra Srivastava

Keyword(s):

Selective Reduction ◽

Value Added ◽

Cu Nanoparticles ◽

Platform Chemicals ◽

Synergistic Enhancement ◽

Reduction And Oxidation ◽

Significant Attention ◽

Lignocellulose Biomass

Furfural (FAL) and 5-hydroxymethylfurfural (HMF) are important and sustainable platform chemicals. They are produced from lignocellulose biomass and attract significant attention as precursors for producing value-added chemicals and fuels. The...

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Effective Chromium Adsorption From Aqueous Solutions and Tannery Wastewater Using Bimetallic Fe/Cu Nanoparticles: Response Surface Methodology and Artificial Neural Network

Air Soil and Water Research ◽

10.1177/11786221211028162 ◽

2021 ◽

Vol 14 ◽

pp. 117862212110281

Author(s):

Ahmed S. Mahmoud ◽

Nouran Y. Mohamed ◽

Mohamed K. Mostafa ◽

Mohamed S. Mahmoud

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Industrial Effluent ◽

Oxygen Demand ◽

Operating Conditions ◽

Tannery Wastewater ◽

P Value ◽

Cu Nanoparticles ◽

Artificial Neural ◽

Cr Removal

Tannery industrial effluent is one of the most difficult wastewater types since it contains a huge concentration of organic, oil, and chrome (Cr). This study successfully prepared and applied bimetallic Fe/Cu nanoparticles (Fe/Cu NPs) for chrome removal. In the beginning, the Fe/Cu NPs was equilibrated by pure aqueous chrome solution at different operating conditions (lab scale), then the nanomaterial was applied in semi full scale. The operating conditions indicated that Fe/Cu NPs was able to adsorb 68% and 33% of Cr for initial concentrations of 1 and 9 mg/L, respectively. The removal occurred at pH 3 using 0.6 g/L Fe/Cu dose, stirring rate 200 r/min, contact time 20 min, and constant temperature 20 ± 2ºC. Adsorption isotherm proved that the Khan model is the most appropriate model for Cr removal using Fe/Cu NPs with the minimum error sum of 0.199. According to khan, the maximum uptakes was 20.5 mg/g Cr. Kinetic results proved that Pseudo Second Order mechanism with the least possible error of 0.098 indicated that the adsorption mechanism is chemisorption. Response surface methodology (RSM) equation was developed with a significant p-value = 0 to label the relations between Cr removal and different experimental parameters. Artificial neural networks (ANNs) were performed with a structure of 5-4-1 and the achieved results indicated that the effect of the dose is the most dominated variable for Cr removal. Application of Fe/Cu NPs in real tannery wastewater showed its ability to degrade and disinfect organic and biological contaminants in addition to chrome adsorption. The reduction in chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), total phosphorus (TP), total nitrogen (TN), Cr, hydrogen sulfide (H2S), and oil reached 61.5%, 49.5%, 44.8%, 100%, 38.9%, 96.3%, 88.7%, and 29.4%, respectively.

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Molecular dynamics simulation of effect of temperature on Cu nanoparticles agglomeration of nanofluids

Journal of Nanoparticle Research ◽

10.1007/s11051-020-05131-y ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Jingtao Wang ◽

Zhiwei Li ◽

Yuting Jia ◽

Bingbing Wang ◽

Zhiming Xu

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Dynamics Simulation ◽

Effect Of Temperature ◽

Cu Nanoparticles

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Facile Synthesis of Carboxymethyl Cellulose Coated Core/Shell SiO2@Cu Nanoparticles and Their Antifungal Activity against Phytophthora capsici

Polymers ◽

10.3390/polym13060888 ◽

2021 ◽

Vol 13 (6) ◽

pp. 888

Author(s):

Nguyen Thi Thanh Hai ◽

Nguyen Duc Cuong ◽

Nguyen Tran Quyen ◽

Nguyen Quoc Hien ◽

Tran Thi Dieu Hien ◽

...

Keyword(s):

Antifungal Activity ◽

Carboxymethyl Cellulose ◽

Chemical Reduction ◽

Low Cost ◽

Phytophthora Capsici ◽

Reduction Process ◽

Spherical Shape ◽

Core Shell ◽

Cu Nanoparticles ◽

Average Size

Cu nanoparticles are a potential material for creating novel alternative antimicrobial products due to their unique antibacterial/antifungal properties, stability, dispersion, low cost and abundance as well as being economical and ecofriendly. In this work, carboxymethyl cellulose coated core/shell SiO2@Cu nanoparticles (NPs) were synthesized by a simple and effective chemical reduction process. The initial SiO2 NPs, which were prepared from rice husk ash, were coated by a copper ultrathin film using hydrazine and carboxymethyl cellulose (CMC) as reducing agent and stable agent, respectively. The core/shell SiO2@Cu nanoparticles with an average size of ~19 nm were surrounded by CMC. The results indicated that the SiO2@Cu@CMC suspension was a homogenous morphology with a spherical shape, regular dispersion and good stability. Furthermore, the multicomponent SiO2@Cu@CMC NPs showed good antifungal activity against Phytophthora capsici (P. capsici). The novel Cu NPs-based multicomponent suspension is a key compound in the development of new fungicides for the control of the Phytophthora disease.

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Supported Cu Nanoparticles as Selective and Stable Catalysts for the Gas Phase Hydrogenation of 1,3-Butadiene in Alkene-Rich Feeds

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.0c08077 ◽

2020 ◽

Author(s):

Giorgio Totarella ◽

Rolf Beerthuis ◽

Nazila Masoud ◽

Catherine Louis ◽

Laurent Delannoy ◽

...

Keyword(s):

Gas Phase ◽

Cu Nanoparticles

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Enhancing the thermoelectric performance of CoSb3-based skutterudite by decoupling the electrical and thermal properties by embedding Cu nanoparticles

Ceramics International ◽

10.1016/j.ceramint.2021.06.242 ◽

2021 ◽

Author(s):

Yiwei Zhao ◽

Yong Liu ◽

Hongyu Ma ◽

Shuping Deng ◽

Haiying Wang ◽

...

Keyword(s):

Thermal Properties ◽

Thermoelectric Performance ◽

Cu Nanoparticles

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Antimicrobial Properties of the Ag, Cu Nanoparticle System

Biology ◽

10.3390/biology10020137 ◽

2021 ◽

Vol 10 (2) ◽

pp. 137

Author(s):

Xinzhen Fan ◽

L’Hocine Yahia ◽

Edward Sacher

Keyword(s):

Reactive Oxygen Species ◽

Biomedical Application ◽

Antimicrobial Properties ◽

Antimicrobial Activities ◽

Oxygen Species ◽

Cu Nanoparticles ◽

Postoperative Infections ◽

Nanoparticle System ◽

Contact Killing ◽

Bacteria And Fungi

Microbes, including bacteria and fungi, easily form stable biofilms on many surfaces. Such biofilms have high resistance to antibiotics, and cause nosocomial and postoperative infections. The antimicrobial and antiviral behaviors of Ag and Cu nanoparticles (NPs) are well known, and possible mechanisms for their actions, such as released ions, reactive oxygen species (ROS), contact killing, the immunostimulatory effect, and others have been proposed. Ag and Cu NPs, and their derivative NPs, have different antimicrobial capacities and cytotoxicities. Factors, such as size, shape and surface treatment, influence their antimicrobial activities. The biomedical application of antimicrobial Ag and Cu NPs involves coating onto substrates, including textiles, polymers, ceramics, and metals. Because Ag and Cu are immiscible, synthetic AgCu nanoalloys have different microstructures, which impact their antimicrobial effects. When mixed, the combination of Ag and Cu NPs act synergistically, offering substantially enhanced antimicrobial behavior. However, when alloyed in Ag–Cu NPs, the antimicrobial behavior is even more enhanced. The reason for this enhancement is unclear. Here, we discuss these results and the possible behavior mechanisms that underlie them.

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