Pt/CdS/7.5Co-Pi photoelectrode was prepared for improving PEC water splitting.
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•Design and fabrication of Pt/CdS/Co-Pi photoanode for efficient PEC water splitting.•Pt serves as an ...electron capture layer to collect electron to facilitate water reduction.•Co-Pi used as cocatalysts to accelerate the surface water oxidation in Pt/CdS/Co-Pi.•It can provide a promising guidelines for photoanodes to realize efficient PEC water splitting.
The recombination of electron-hole pairs and the slow surface catalytic reactions have been deemed as the core problem affecting the efficiency of photoelectrochemical (PEC) performance. Here we synthesized hexagonal CdS photoanode on FTO substrate by hydrothermal method. Cobalt-phosphate (Co-Pi) and Pt cocatalysts were simultaneously decorated on the inner and outer surfaces of CdS (denoted as Pt/CdS/Co-Pi), which showed efficient charge separation/transfer performance on account of trapping the electrons with Pt and transferring holes with Co-Pi. As a result, the Pt/CdS/7.5Co-Pi photoanode showed a maximum photo-current of 5.05 mA/cm−2 at 0.28 V vs RHE under solar simulated illumination, which was 8.3 times higher than that of pure CdS photoanode. This work presents a promising guideline to design and fabricate an eco-friendly and sunlight-driven photoanode for the PEC water-splitting system.
In this paper, the bubbly flow characteristics of a Venturi channel was revealed by using the population balance model (PBM) within the framework of computational fluid dynamics (CFD) numerical ...simulation and focused on the bubble size distribution and pressure drop △P of different regions. The simulation results indicated that bubble breakup mainly occurred in the diverging section of the Venturi channel, and the average diameter of the daughter bubbles davg in the sidewall region was much smaller than that in the central region. Through the correlational analysis between the bubble size distribution and turbulent flow field, the bubble breakup in the diverging section was positively related to the turbulent flow. Considering the influence of geometric parameters on davg and △P, the davg decreased and △P increased with the increasing of the diverging angle β. As the throat diameter D increased, the davg increased and △P decreased gradually. In order to quantify the bubble breakup characteristics, the concept of bubble breakup ratio τ is introduced and defined as the ratio of inlet average bubble diameter di to the outlet average bubble diameter do. Through dimensionless transformation, the fitting relationship between τ or △P and angle ratio a was Sinusoidal function (SINE), respectively, and was Boltzmann with the throat length‐diameter ratio b. Due to the relationship of first‐order linear function between τ and △P, the bubble breakup ratio can be obtained by measuring the pressure drop of the Venturi tube, which was significant to the practical engineering application.
Detection of damage to the blood–brain barrier (BBB) is important for the diagnosis of brain diseases and therapeutic drug evaluation. The widely used probe, Evans blue, suffers from low specificity ...and high toxicity in vivo. It is shown that organic nanoparticles with tuneable size, good biocompatibility, and aggregation‐induced emission characteristics offer high detection specificity to detect BBB damage via a photothrombotic ischemia rat model.
Fine-tuning electron acceptors through changing one cyano group to an amide generates a more stable and emissive fluorophore with the character of aggregation-induced emission. Conjugation between ...the new fluorophore and CFFKDEL generated an excellent ER targeting light-up probe with high specificity and good photostability.
The compact flotation unit (CFU) has been widely used in offshore oilfield-produced water treatment with the characteristics of compact structure and high oil removal efficiency. However, there is no ...published literature talking about CFU’s application in refinery wastewater treatment. In this paper, an innovative designed two-stage series BIPTCFU process diagram for refinery wastewater treatment was proposed. The structural design of the core BIPTCFU with a capacity of 20 m3/h was also carried out. After that, the manufactured industrial prototype of BIPTCFU-III-20 was tested in a SINOPEC petrochemical wastewater treatment plant. The single-factor operation test results show that with the increase of gas-liquid volume ratio, the oil removal efficiency of the BIPTCFU-III-20 increases first and then stabilizes. The reason can be ascribed to the microbubble number density which contributes to the oil removal efficiency. With the increase of inlet water flow rate, the oil removal efficiency first increases and then decreases. The reason is that as the inlet flow rate increases and approaches the rated treatment capacity, a stable swirling flow field is gradually formed in the vessel which benefits to the oil removal performance. While when the inlet water flow rate exceeds the rated capacity, the calculated hydraulic retention time was too short to complete the air flotation process. Under the optimal operation parameters, the oil removal performance of the BIPTCFU-III-20 on refinery wastewater was remarkable, and the average oil removal efficiency was 81.65 % when the inlet oil content was higher (1307 mg/L ∼ 4486 mg/L). While, when the inlet oil content is lower (150 mg/L ∼ 393 mg/L), the average oil removal efficiency was 77.75 %. The effect of low inlet oil content on the oil removal rate is more significant than that of high oil content. Based on the above basic research results, an industrial BIPTCFU with a rated capacity of 100 m3/h was constructed. The remarkable oil removal performance of the refinery wastewater was further verified.
•An innovative designed BIPTCFU for refinery wastewater treatment was proposed.•The oil removal efficiency changes regularly with the increase of operation parameters.•The oil removal performance was remarkable under the optimal operation parameters.•The effect of low inlet oil content on oil removal rate is more significant than that of high.
The paper explores the use of swirling flow in the flotation process to enhance the removal of oil from oily sewage, thereby reducing environmental hazards. The study focuses on understanding the ...dynamic movement of dispersed oil droplets and their coalescence efficiency, as these factors play a crucial role in the overall flotation performance. By introducing a centrifugal force field into the air flotation flow, the collision and adhesion efficiency between oil droplets and bubbles, as well as the migration and separation efficiency, can be significantly improved. A laboratory swirling flotation cell was designed, and an experimental system was set up to conduct tests. The study employed a combination of experimental tests and CFD simulation, coupled with the Population Balance Model, to investigate the effects of swirling flow on the oil-water dynamic separation characteristics during the flotation process. The numerical simulation results were validated through online measurement of oil droplet size distribution using FBRM, ensuring a deviation within 3.0%. Additionally, the terminal velocity distribution of dispersed oil droplets under various swirl intensities in the annular space was analyzed. The study also examined the impact of turbulence intensity and swirl separation time on the oil-water separation process. The experimental result indicated that the tangential velocity attenuation is significant during swirling, and with an attenuation ratio of up to 84.8% when the oily sewage flows out of the annular space. The optimal turbulence intensity for promoting the collision coalescence process of oil droplets is found to be 6.5%, and the most suitable swirl separation time is 7.5 seconds.
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Based on an Anton Paar MCR302 electro-rheometer and the rheological analysis method, this paper mainly investigated the influences of different parameters including shear rate, ...electric field strength, electric field frequency and voltage waveform as well as the water cut on the electrostatic coalescence of water-in-crude-oil emulsions by taking the relative viscosity reduction as the critical evaluated means, which is supposed to provide guidance for selecting the optimum flow-field and electric-field operation parameters of electric dehydrators.
•Chord Length Distribution (CLD) of dispersed water droplets within water-in-crude-oil emulsions is measured online.•Relative viscosity reduction is taken as the main evaluation means to study the electric-field and flow-field parameters.•Threshold shear rate, optimum electric field strength, frequency and the most efficient voltage waveform for electrocoalescence are discussed.•Great application potential of high frequency/high voltage AC electric field in treating the highly conductive crude oil emulsions is confirmed.
The viscosity–temperature characteristics and phase inversion point as well as the chord lengths distribution of dispersed droplets have been investigated. The relative viscosity reduction is then effectively taken as the evaluation means to investigate the effects of shear rate, electric field strength, frequency, voltage waveform, and initial water cut on the electrocoalescence efficiency experimentally systematically. It is determined that the phase inversion point is located between 35%–45%. The chord lengths of dispersed droplets are concentrated in range of 10–150μm and the average value is 61.3μm for the water-in-crude-oil emulsions sample. We found that the coalescence efficiency can be improved by increasing shear rate to some extent while keeping other parameters unchanged, but decreased instead with the shear rate exceeding 50s−1, which suggests that only the appropriate flow shear condition can help to promote the electrostatic coalescence. Meanwhile, the present work has demonstrated that there exists optimum electric field strength(8kV/cm) and frequency(2kHz) for the given water-in-crude-oil emulsions, and the ranking of three voltage waveforms in decreasing order of coalescence efficiency is AC square, triangular and sinusoidal waveform. In addition, with the three kinds of voltage waveforms, the coalescence efficiency are all significantly improved as the water cut increases from 10% up to 40%, which demonstrates the good performance of high frequency/high voltage electric field for treating crude oil emulsions with high water cut.
Transplantation of differentiated neurons derived from either human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs) is an emerging therapeutic strategy for various ...neurodegenerative diseases. One important aspect of transplantation is the accessibility to track and control the activity of the stem cells-derived neurons post-transplantation. Recently, the characteristics of organic nanoparticles (NPs) with aggregation-induced emission (AIE) have emerged as efficient cell labeling reagents, where positive outcomes were observed in long-term cancer cell tracing in vivo. In the current study, we designed, synthesized, and analyzed the biocompatibility of AIE-NPs in cultured neurons such as in mouse neuronal progenitor cells (NPCs) and hESC-derived neurons. Our data demonstrated that AIE-NPs show high degree of penetration into cells and presented intracellular long-term retention in vitro without altering the neuronal proliferation, differentiation, and viability. Furthermore, we have tracked AIE-NPs labeled neuronal grafts in mouse brain striatum in various time points post-transplantation. We demonstrated prolonged cellular retention of AIE-NPs labeled neuronal grafts 1 month post-transplantation in mouse brain striatum. Lastly, we have shown activation of brain microglia in response to AIE-NPs labeled grafts. Together, these findings highlight the potential application of AIE-NPs in neuronal transplantation.
In this study, the gas-liquid two-phase mixing process and the microbubbles formation process in a jet flow field has been investigated by using a self-designed on-line measurement system for ...measuring bubble generation characteristics and the Volume of Fluid (VOF) model in numerical simulation methods for analyzing flow field distribution characteristics. The effect of turbulence intensity on the dynamic size distribution of microbubble has been considered. The characteristics and duration of the three stages during the bubble breaking process, namely, surface oscillation stage, surface tension stage and fracture stage, were analyzed. The results show that the increase of turbulence intensity in jet flow will further promote the imbalance between the external deformation force and the surface tension resisting the deformation of the bubble, and promote the breaking probability of bubble. However, when the bubble breaks to a sufficiently small size, the surface tension against bubble deformation will increase sharply, the surface free energy needed to overcome for bubble breakage is very large, and the breakage probability of bubble will significantly decrease. Compared with the breaking process of bubbles, the increase in turbulence intensity will greatly promote the bubble coalescence process, which will ultimately become the main reason for affecting the bubble size distribution. Moreover, the influence of flow field distribution characteristics on bubble size distribution and average bubble size change is analyzed by using Population Balance Model.
By employment of an aptamer-initiated hybridization chain reaction (HCR) to enhance the enzyme biomineralization of cupric subcarbonate, this work develops a novel colorimetric biosensing method for ...protein analysis. The HCR product was used to specifically attach a large amount of urease-functionalized gold nanoparticles (Au NPs) for the preparation of a gold nanoprobe. After the sandwich biorecognition reactions, this nanoprobe could be quantitatively captured onto the antibody-functionalized magnetic bead (MB) platform. Then, numerous copper ions would be enriched onto the MB surface through the urease-induced biomineralization of cupric subcarbonate. Based on the complete release of Cu2+ ions for the sensitive copper chromogenic reaction, convenient colorimetric signal transduction was thus achieved for the quantitative analysis of the target analyte of the carcinoembryonic antigen. The HCR product provides a large number of biotin sites for the attachment of Au NP nanotags. The biomineralization reaction of high-content urease loaded onto Au NPs leads to highly efficient Cu2+ enrichment for signal amplification. So this method features excellent performance including a very wide linear range and a low detection limit down to 0.071 pg mL-1. In addition, the satisfactory results of real sample experiments reveal that this method possesses huge potential for practical applications.
