Ultrasensitive thrombin detection based on direct electrochemistry of highly loaded hemoglobin spheres-encapsulated platinum nanoparticles as labels and electrocatalysts

Driven by the need to control flow separations in highly loaded compressors, a numerical investigation is carried out to study the control effect of wavy blades in a linear compressor cascade. Two types of wavy blades are studied with wavy blade-A having a sinusoidal leading edge, while wavy blade-B having pitchwise sinusoidal variation in the stacking line. The influence of wavy blades on the cascade performance is evaluated at incidences from −1° to +9°. For the wavy blade-A with suitable waviness parameters, the cascade diffusion capacity is enhanced accompanied by the loss reduction under high incidence conditions where 2D separation is the dominant flow structure on the suction surface of the unmodified blade. For well-designed wavy blade-B, the improvement of cascade performance is achieved under low incidence conditions where 3D corner separation is the dominant flow structure on the suction surface of the baseline blade. The influence of waviness parameters on the control effect is also discussed by comparing the performance of cascades with different wavy blade configurations. Detailed analysis of the predicted flow field shows that both the wavy blade-A and wavy blade-B have capacity to control flow separation in the cascade but their control mechanism are different. For wavy blade-A, the wavy leading edge results in the formation of counter-rotating streamwise vortices downstream of trough. These streamwise vortices can not only enhance momentum exchange between the outer flow and blade boundary layer, but also act as the suction surface fence to hamper the upwash of low momentum fluid driven by cross flow. For wavy blade-B, the wavy surface on the blade leads to a reduction of the cross flow upwash by influencing the spanwise distribution of the suction surface static pressure and guiding the upwash flow.

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Green synthesis: Proposed mechanism and factors influencing the synthesis of platinum nanoparticles

Green Processing and Synthesis ◽

10.1515/gps-2020-0041 ◽

2020 ◽

Vol 9 (1) ◽

pp. 386-398 ◽

Cited By ~ 1

Author(s):

Mahmood S. Jameel ◽

Azlan Abdul Aziz ◽

Mohammed Ali Dheyab

Keyword(s):

Green Synthesis ◽

Reaction Temperature ◽

Platinum Nanoparticles ◽

Energy Requirement ◽

Average Particle Size ◽

High Energy ◽

Energy Utilization ◽

Critical Parameters ◽

Synthesis Process ◽

Average Particle

AbstractPlatinum nanoparticles (Pt NPs) have attracted interest in catalysis and biomedical applications due to their unique structural, optical, and catalytic properties. However, the conventional synthesis of Pt NPs using the chemical and physical methods is constrained by the use of harmful and costly chemicals, intricate preparation requirement, and high energy utilization. Hence, this review emphasizes on the green synthesis of Pt NPs using plant extracts as an alternative approach due to its simplicity, convenience, inexpensiveness, easy scalability, low energy requirement, environmental friendliness, and minimum usage of hazardous materials and maximized efficiency of the synthesis process. The underlying complex processes that cover the green synthesis (biosynthesis) of Pt NPs were reviewed. This review affirms the effects of different critical parameters (pH, reaction temperature, reaction time, and biomass dosage) on the size and shape of the synthesized Pt NPs. For instance, the average particle size of Pt NPs was reported to decrease with increasing pH, reaction temperature, and concentration of plant extract.

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Ultrafine Platinum Nanoparticles Supported on Covalent Organic Frameworks As Stable and Reusable Oxidase-Like Catalysts for Cellular Glutathione Detection

ACS Applied Nano Materials ◽

10.1021/acsanm.1c00752 ◽

2021 ◽

Author(s):

Peng Jin ◽

Xiaoying Niu ◽

Zixi Gao ◽

Xuqi Xue ◽

Fang Zhang ◽

...

Keyword(s):

Platinum Nanoparticles ◽

Covalent Organic Frameworks

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