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1.
Small ; : e2405379, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363823

RESUMO

Aqueous zinc-ion batteries (AZIBs) are considered as a promising energy storage system because of good safety, low cost, abundant resources, and environmental friendliness. However, the bottlenecks including dendrite growth, hydrogen evolution, and corrosion seriously limit their practical application. Herein, a novel ZnSn(OH)6 coating layer with rich hydroxyl groups is employed to achieve highly stable Zn anode. The hydroxyl groups can feasibly interact with H2O molecules, contributing to the desolvation of hydrated Zn2+ and the inhibition of side reactions on Zn anode surface. Furthermore, according to the DFT calculation, the adsorption energy of Zn2+ among various sites on the surface of ZnSn(OH)6 coating layer is relatively large, which helps the uniform distribution of Zn2+ flux and the prevention of dendrite growth. Consequently, the ZnSn(OH)6@Zn anode delivers ultra-long cycle life (6770 h), low polarization voltage (27 mV), and high Coulombic efficiency (99.2% over 800 cycles) at 1 mA cm-2, 1 mAh cm-2. Besides, the assembled NaV3O8·xH2O//ZnSn(OH)6@Zn full cell can operate stably for 1500 cycles at 2 A g-1 with a high specific capacity of 144.9 mAh g-1, demonstrating an excellent application potential. This simple and effective coating layer with high electrochemical performance provides an appealing strategy for the development of rechargeable AZIBs.

2.
Small ; 20(29): e2310497, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38351670

RESUMO

Aqueous zinc ion batteries have received widespread attention due to their merits of high safety, high theoretical specific capacity, low cost, and environmental benignity. Nevertheless, the irreversible issues of Zn anode deriving from side reactions and dendrite growth have hindered its commercialization in large-scale energy storage systems. Herein, a zinc phosphate tetrahydrate (Zn3(PO4)2·4H2O, ZnPO) coating layer is in situ formed on the bare Zn by spontaneous redox reactions at room temperature to tackle the above issues. Particularly, the dense and brick-like ZnPO layer can effectively separate the anode surface from the aqueous electrolyte, thus suppressing the serious side reactions. Moreover, the ZnPO layer with high ionic conductivity, high Zn2+ transference number, and low nucleation barrier permits rapid Zn2+ transport and enables uniform Zn deposition, ensuring dendrite-free Zn deposition. As a result, the ZnPO@Zn symmetric battery achieves a high Coulombic efficiency of 99.8% and displays ultrahigh cycle stability over 6000 h (> 8 months), far surpassing its counterparts. Furthermore, the ZnPO@Zn||MnO2 full battery exhibits excellent electrochemical performances. Therefore, this work provides a new reference for simple and large-scale preparation of highly reversible Zn metal anodes, and has great potential for practical applications.

3.
Chemistry ; 29(15): e202203165, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36514875

RESUMO

To simultaneously improve the hole extraction ability of the BiVO4 photoanode and accelerate the surface reaction kinetics, herein, a carbon nanolayer conformally coated Fe2 O3 (C-Fe2 O3 ) as oxygen evolution catalyst (OEC) is loaded on the H2 plasma treated nanoporous BiVO4 (BVO(H2 )) surface by a hydrothermal reaction. It is found that the H2 plasma induced vacancies in BVO remarkably increases the conductivity, and the C-Fe2 O3 enables hole extraction from the bulk to the surface as well as efficient hole injection to the electrolyte. As a result, the C-Fe2 O3 /BVO(H2 ) photoanode achieves a photocurrent density of 4.4 mA/cm2 at 1.23 V vs. reversible hydrogen electrode (RHE) and an ABPE value of 1.5 % at 0.68 V vs. RHE, which are 4.8-fold and 13-fold higher than that of BVO photoanode, respectively.

4.
Nanotechnology ; 34(7)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36399774

RESUMO

In this paper, via a facile wet coating method, the LaPO4coating layer has been introduced onto the LiNi0.87Co0.09Al0.04O2(NCA) surface while a small part of La3+has also been doped on the surface to realize the dual functions modification of coating and doping. The morphology and structure of the samples were investigated by XRD, SEM and TEM measurements. The chemical compositions of the samples were analyzed via EDS and XPS data. The results showed that the coating of LaPO4and the doping of La3+were successfully achieved on the surface of NCA. Electrochemical tests indicate that the sample modified with 2 wt% LaPO4(L2-NCA) possesses the best electrochemical performance. After 100 cycles, compared with the capacity retention rate of pristine NCA of 87.1%/74.2% at 0.5 C at 25 °C/60 °C, L2-NCA showed better cycling stability, and the capacity retention rate increased to 96.0%/85.1%, respectively. Besides, the rate performance of the modified samples at 1 C, 2 C and 5 C were also significantly improved. These satisfactory results reveal that the surface modification of LaPO4provides a feasible scheme to uprate the performance of Ni-rich cathode materials.

5.
Nanotechnology ; 33(4)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34644688

RESUMO

LiNi0.8Co0.15Al0.05O2(NCA), a promising ternary cathode material of lithium-ion batteries, has widely attracted attention due to its high energy density and excellent cycling performance. However, the presence of residual alkali (LiOH and Li2CO3) on the surface will accelerate its reaction with HF from LiPF6, resulting in structural degradation and reduced safety. In this work, we develop a new coating material, LiH2PO4, which can effectively optimize the residual alkali on the surface of NCA to remove H2O and CO2and form a coating layer with excellent ion conductivity. Under this strategy, the coated sample NCA@0.02Li3PO4(P2-NCA) provides a capacity of 147.8 mAh g-1at a high rate of 5 C, which is higher than the original sample (126.5 mAh g-1). Impressively, the cycling stabilities of P2-NCA under 0.5 C significantly improved from 85.2% and 81.9% of pristine-NCA cathode to 96.1% and 90.5% at 25 °C and 55 °C, respectively. These satisfied findings indicate that this surface modification method provides a feasible strategy toward improving the performance and applicability of nickel-rich cathode materials.

6.
Chem Pharm Bull (Tokyo) ; 65(9): 848-853, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28867712

RESUMO

External lubrication is a useful method which reduces the adhesion of powder to punches and dies by spraying lubricants during the tableting process. However, no information is available on whether the tablets prepared using an external lubrication system can be applicable for a film coating process. In this study, we evaluated the adhesion force of the film coating layer to the surface of tablets prepared using an external lubrication method, compared with those prepared using internal lubrication method. We also evaluated wettability, roughness and lubricant distribution state on the tablet surface before film coating, and investigated the relationship between peeling of the film coating layer and these tablet surface properties. Increasing lubrication through the external lubrication method decreased wettability of the tablet surface. However, no change was observed in the adhesion force of the film coating layer. On the other hand, increasing lubrication through the internal lubrication method, decreased both wettability of the tablet surface and the adhesion force of the film coating layer. The magnesium stearate distribution state on the tablet surface was assessed using an X-ray fluorescent analyzer and lubricant agglomerates were observed in the case of the internal lubrication method. However, the lubricant was uniformly dispersed in the external lubrication samples. These results indicate that the distribution state of the lubricant affects the adhesion force of the film coating layer, and external lubrication maintained sufficient lubricity and adhesion force of the film coating layer with a small amount of lubricant.


Assuntos
Comprimidos/química , Tecnologia Farmacêutica/métodos , Adesividade , Lubrificantes/química , Ácidos Esteáricos/química , Propriedades de Superfície , Molhabilidade
7.
Sensors (Basel) ; 16(9)2016 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-27608027

RESUMO

High temperature characteristics of langasite surface acoustic wave (SAW) devices coated with an AlN thin film have been investigated in this work. The AlN films were deposited on the prepared SAW devices by mid-frequency magnetron sputtering. The SAW devices coated with AlN films were measured from room temperature to 600 °C. The results show that the SAW devices can work up to 600 °C. The AlN coating layer can protect and improve the performance of the SAW devices at high temperature. The SAW velocity increases with increasing AlN coating layer thickness. The temperature coefficients of frequency (TCF) of the prepared SAW devices decrease with increasing thickness of AlN coating layers, while the electromechanical coupling coefficient (K²) of the SAW devices increases with increasing AlN film thickness. The K² of the SAW devices increases by about 20% from room temperature to 600 °C. The results suggest that AlN coating layer can not only protect the SAW devices from environmental contamination, but also improve the K² of the SAW devices.

8.
ACS Appl Mater Interfaces ; 16(5): 6623-6631, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38261021

RESUMO

The development of aqueous zinc-ion batteries (AZIBs) is hindered by dendrites and side reactions, such as interfacial byproducts, corrosion, and hydrogen evolution. The construction of an artificial interface protective layer on the surface of the zinc anode has been extensively researched due to its strong operability and potential for large-scale application. In this study, we have designed an organic hydrophobic hybrid inorganic intercalation composite coating to achieve stable Zn2+ plating/stripping. The hydrophobic poly(vinylidene fluoride) (PVDF) effectively prevents direct contact between free water and the zinc anode, thereby mitigating the risk of dendrite formation. Simultaneously, the inorganic layer of vanadium phosphate (VOPO4·2H2O) after the insertion of polyaniline (PA) establishes a robust ion channel for facilitating rapid transport of Zn2+, thus promoting uniform electric field distribution and reducing concentration polarization. As a result, the performance of the modified composite PVDF/PA-VOP@Zn anode exhibited significant enhancement compared with that of the bare zinc anode. The assembled symmetric cell exhibits an exceptionally prolonged lifespan of 3070 h at a current density of 1 mA cm-2, while the full battery employing KVO as the cathode demonstrates a remarkable capability to undergo 2000 cycles at 5 A g-1 with a capacity retention rate of 78.2%. This study offers valuable insights into the anodic modification strategy for AZIBs.

9.
J Colloid Interface Sci ; 679(Pt A): 197-205, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39362144

RESUMO

The electrochemical performance of high-performance lithium-sulfur (Li-S) batteries is affected by many factors such as shuttle effect and lithium dendrites. To effectively solve this problem, a hexagonal star-shaped composite catalyst containing Co-N-C active sites (Co-NC-X) has been rationally developed under the joint action of Zn2+ and Co2+ bimetallic ions. By modifying it to the Li-S battery separator, Co-NC-X can not only act as a physical barrier to effectively prevent the diffusion of lithium polysulfide (LiPS), but also the special morphology can expose more active sites and have a strong chemisorption effect on LiPS, which effectively promotes the redox conversion of LiPS and mitigates the shuttle effect. Li-S battery with Co-NC-X exhibits excellent electrochemical performance. It has a high specific capacity and stable cycling performance, with an initial discharge capacity of 1406.9 mAh·g-1 at 0.2 C and 876.8 mAh·g-1 at 2 C, and a lower capacity decline rate of 0.093 % for 500 cycles.

10.
J Colloid Interface Sci ; 670: 449-459, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38772261

RESUMO

Aqueous zinc ion batteries (ZIBs) have been considered promising energy storage systems due to their excellent electrochemical performance, environmental toxicity, high safety and low cost. However, uncontrolled dendrite growth and side reactions at the zinc anode have seriously hindered the development of ZIBs. Herein, we prepared the carbon nanoparticles layer coated zinc anode with (103) crystal plane preferential oriented crystal structure (denoted as C@RZn) by a facile one-step vapor deposition method. The preferential crystallographic orientation of (103) crystal plane promotes zinc deposition at a slight angle, effectively preventing the formation of Zn dendrites on the surface. In addition, the hydrophobic layer of carbon layer used as an inert physical barrier to prevent corrosion reaction and a buffer during volume changes, thus improving the reversibility of the zinc anode. As a result. the C@RZn anode achieves a stable cycle performance of more than 3000 h at 1 mA cm-2 with CE of 99.77 % at 5 mA cm-2. The full battery with C@RZn anode and Mn-doped V6O13 (MVO) cathode show stability for 5000 cycles at the current density of 5 A g-1. This work provides a new approach for the design of multifunctional interfaces for Zn anode.

11.
ACS Appl Mater Interfaces ; 16(8): 10692-10702, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38356239

RESUMO

Lithium-ion batteries (LIBs) are known for their high energy density but exhibit poor cyclic stability and safety risks due to side reactions between the electrode and electrolyte. To address these issues, a novel approach involving construction of a polymer coating layer (PCL) via in situ self-polymerization using 2,2,3,4,4,4-hexafluorobutyl methacrylate (HFBM) as an electrolyte additive on the cathode is proposed. The PCL endows the electrolyte with a high onset oxidation potential (4.78 V) and lithium-ion transference number (0.52). The uniform and robust in situ constructed PCL can effectively inhibit the severe irreversible side reactions and suppress harmful reactions, thus providing a protective barrier against degradation. The resulting Li||LiNi0.8Co0.1Mn0.1O2 batteries exhibit an improved discharge capacity retention of 80% at 1C over 100 cycles. These results demonstrate that the in situ self-polymerization strategy holds promising potential for enhancing LIB performance and long-term stability, especially when high-voltage cathode materials are used.

12.
J Colloid Interface Sci ; 663: 532-540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38422978

RESUMO

The performance of thin lithium metal anodes is affected due to issues that weaken the electrode-electrolyte interphase. In this work, a coating layer serving as a Li+ traffic controller based on hexadecyl trimethyl ammonium bis(trifluoromethanesulphonyl)imide ([CTA][TFSI]) and poly (vinylidene difluoride co-hexafluoropropylene) (P(VDF-HFP)) is used to stabilize the thin lithium metal interface. The CTA+ ions in the coating layer can effectively regulate the distribution of Li+ concentration to promote uniform deposition of lithium. The anion of [CTA][TFSI] can optimize solid electrolyte interphase (SEI) with inorganic-rich components, which improve the ionic conductivity and reaction kinetics. Furthermore, the flexible polymer skeleton can fortify the fragile SEI, facilitating the consistent operation of the battery. Due to these improvements, a thin Li metal anode (4 mAh cm-2) with a coating layer in a Li||Li symmetric cell demonstrates a lifespan of 600 h at 1 mA cm-2 and 1 mAh cm-2. Notably, full cells with an ultra-low negative electrode/positive electrode = 1 (N/P = 1) demonstrate a stable performance over 200 cycles and 90 cycles at 0.5C and 1C (1C = 170 mA g-1), respectively.

13.
J Colloid Interface Sci ; 663: 601-608, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38428117

RESUMO

Li-rich layered oxides cathodes (LLOs) as the promising next-generation cathode materials can provide ultrahigh capacity and energy density due to their distinctive anionic redox chemistry. Unfortunately, severe interfacial side reactions, surface structural degradation and sluggish Li+ kinetics have resulted in low initial coulombic efficiency (ICE), capacity decay and poor rate performance, restricting their practical applications for high-energy-density lithium-ion batteries. Herein, Surface structure regulation strategy used as surface modified agent is proposed to activate the anionic redox chemistry via ammonium tungstate treatment. Experimental results showcase that dual coating layer spinel-like structure LiMn2O4 and Li2WO4 have been successfully constructed on the surface of LLOs. The surface spinel-like structure providing 3 D Li+ diffusion channels together with fast-ion conductive layer decrease the interfacial Li+ diffusion barrier and boost the fasting Li+ kinetics. In addition, the in-situ reconstruction layer can further alleviate the interfacial side reactions and reinforce the surface structural stability. As a result, the ICE of modified LLOs can be precisely increased from 74.71 % to 107.42 % with the adjustment of ammonium tungstate usage. Moreover, it delivers a high reversible capacity of 279.5 mAh/g at 0.1 C, as well as excellent rate capability with capacity of 147.2 mAh/g at 5 C. This work provides a significant reference for designing high-energy-density LLOs via surface structure regulation strategy.

14.
BMC Chem ; 17(1): 180, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082361

RESUMO

Nanoparticle-based composites have the potential to meet requirements for radiosensitization in both therapeutic and diagnostic applications. The radiosensitizing properties of nanoparticles could be reliant on the nature of their coating layer. Any gains in reduced toxicity and aggregation or improved delivery to tumor cells for coated nanoparticles must be weighed against the loss of dose enhancement. The radiosensitization potential of coated NPs is confirmed by numerous studies but in most of them, the coating layer is mostly applied to reduce toxicity of the NPs and for stability and biocompatibility aims. While the direct effects of the coating layer in radiosensitization-were ignored and not considered. This review provides an overview of double-edged impact of nanoparticle coating on the radiosensitization potential of nanostructures and discusses the challenges in choosing appropriate coating material in the aim of achieving improved radioenhancement. Coating layer could affect the radiosensitization processes and thereby the biological outcomes of nanoparticle-based radiation therapy. The physicochemical properties of the coating layer can be altered by the type of the coating material and its thickness. Under low-energy photon irradiation, the coating layer could act as a shield for nanoparticles capable of absorb produced low-energy electrons which are important levers for local and nanoscopic dose enhancement. Also, it seems that the coating layer could mostly affect the chemical process of ROS production rather than the physicochemical process. Based on the reviewed literature, for the irradiated coated nanoparticles, the cell survival and viability of cancer cells are decreased more than normal cells. Also, cell cycle arrest, inhibition of cell proliferation, DNA damage, cell death and apoptosis were shown to be affected by coated metallic nanoparticles under irradiation.

15.
ACS Appl Mater Interfaces ; 15(48): 55570-55586, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38058105

RESUMO

Recently, aqueous zinc-ion batteries (ZIBs) have become increasingly attractive as grid-scale energy storage solutions due to their safety, low cost, and environmental friendliness. However, severe dendrite growth, self-corrosion, hydrogen evolution, and irreversible side reactions occurring at Zn anodes often cause poor cyclability of ZIBs. This work develops a synergistic strategy to stabilize the Zn anode by introducing a molybdenum dioxide coating layer on Zn (MoO2@Zn) and Tween 80 as an electrolyte additive. Due to the redox capability and high electrical conductivity of MoO2, the coating layer can not only homogenize the surface electric field but also accommodate the Zn2+ concentration field in the vicinity of the Zn anode, thereby regulating Zn2+ ion distribution and inhibiting side reactions. MoO2 coating can also significantly enhance surface hydrophilicity to improve the wetting of electrolyte on the Zn electrode. Meanwhile, Tween 80, a surfactant additive, acts as a corrosion inhibitor, preventing Zn corrosion and regulating Zn2+ ion migration. Their combination can synergistically work to reduce the desolvation energy of hydrated Zn ions and stabilize the Zn anodes. Therefore, the symmetric cells of MoO2@Zn∥MoO2@Zn with optimal 1 mM Tween 80 additive in 1 M ZnSO4 achieve exceptional cyclability over 6000 h at 1 mA cm-2 and stability (>700 h) even at a high current density (5 mA cm-2). When coupling with the VO2 cathode, the full cell of MoO2@Zn∥VO2 shows a higher capacity retention (82.4%) compared to Zn∥VO2 (57.3%) after 1000 cycles at 5 A g-1. This study suggests a synergistic strategy of combining surface modification and electrolyte engineering to design high-performance ZIBs.

16.
J Colloid Interface Sci ; 642: 120-128, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37001451

RESUMO

The exploration of high-performance electrocatalysts for the oxygen evolution reaction (OER) is crucial and urgent for the fast development of green and renewable hydrogen energy. Herein, an ultra-fast and energy-efficient preparation strategy (microwave-assisted rapid in-situ pyrolysis of organometallic compounds induced by carbon nanotube (CNT)) is developed to obtain iron/carbon (Fe/C) heterogeneous materials (Fe/Fe3C particles wrapped by carbon coating layer). The thickness of the carbon coating layer can be adjusted by changing the content and form of carbon in the metal sources during the fast preparation process. Fe/Fe3C-A@CNT using iron acetylacetonate as metal sources possesses unique Fe/C heterogeneous, small Fe/Fe3C particles encapsulated by the thin carbon coating layer (1.77 nm), and obtains the optimal electron penetration effect. The electron penetration effect derives from the redistribution of charge between the surface carbon coating layer and inner Fe/Fe3C nanoparticles efficiently improving both catalytic activity and stability. Therefore, Fe/Fe3C-A@CNT shows efficient OER catalytic activity, just needing a low overpotential of 292 mV to reach a current density of 10 mA cm-2, and long-lasting stability. More importantly, the unique control strategy for carbon thickness in this work provides more opportunity and perspective to prepare robust metal/carbon-based catalytic materials at the nanoscale.

17.
Int J Pharm ; 643: 123096, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37268027

RESUMO

Optical Coherence Tomography (OCT) has recently gained attention as a promising technology for in-line monitoring of pharmaceutical film-coating processes for (single-layered) tablet coatings and end-point detection with commercial systems. An increasing interest in the investigation of multiparticulate dosage forms with mostly multi-layered coatings below 20 µm final film thickness demands advancement in OCT technology for pharmaceutical imaging. We present an ultra-high-resolution (UHR-) OCT and investigate its performance based on three different multiparticulate dosage forms with different layer structures (one single-layered, two multi-layered) with layer thicknesses in a range from 5 to 50 µm. The achieved system resolution of 2.4 µm (axial) and 3.4 µm (lateral, both in air) enables the assessment of defects, film thickness variability and morphological features within the coating, previously unattainable using OCT. Despite the high transverse resolution, the provided depth of field was found sufficient to reach the core region of all dosage forms under test. We further demonstrate an automated segmentation and evaluation of UHR-OCT images for coating thicknesses, where human experts struggle using today's standard OCT systems.


Assuntos
Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Comprimidos , Propriedades de Superfície
18.
ACS Nano ; 16(9): 14539-14548, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36067370

RESUMO

Aqueous zinc-ion batteries (AZIBs) are attractive energy storage devices that benefit from improved safety and negligible environmental impact. The V2O5-based cathodes are highly promising, but the dissolution of vanadium is one of the major challenges in realizing their stable performance in AZIBs. Herein, we design a Ti3C2Tx MXene layer on the surface of V2O5 nanoplates (VPMX) through a van der Waals self-assembly approach for suppressing vanadium dissolution during an electrochemical process for greatly boosting the zinc-ion storage performance. Unlike conventional V2O5/C composites, we demonstrate that the VPMX hybrids offer three distinguishable features for achieving high-performance AZIBs: (i) the MXene layer on cathode surface maintains structural integrity and suppresses V dissolution; (ii) the heterointerface between V2O5 and MXene enables improved host electrochemical kinetics; (iii) reduced electrostatic repulsion exists among host layers owing to the lubricating water molecules in the VPMX cathode, facilitating interfacial Zn2+ diffusion. As a result, the as-made VPMX cathode shows a long-term cycling stability over 5000 cycles, surpassing other reported V2O5-based materials. Especially, we find that the heterointerface between V2O5 and MXene and lubricated water molecules in the host can achieve an enhanced rate capability (243.6 mAh g-1 at 5.0 A g-1) for AZIBs.

19.
Polymers (Basel) ; 14(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36501464

RESUMO

Water that penetrates through cracks in concrete can corrode steel bars. There is a need for reliable and practical seepage sensing technology to prevent failure and determine the necessary maintenance for a concrete structure. Therefore, we propose a modified plasma-assisted electrochemical exfoliated graphite (MPGE) nanosheet smart tag. We conducted a comparative study of standard and modified RFID smart tags with sensor technology for seepage detection in concrete. The performance of both smart tags was tested and verified for seepage sensing in concrete, characterized by sensor code and frequency values. Seepage was simulated by cracking the concrete samples, immersing them for a designated time, and repeating the immersing phase with increasing durations. The test showed that the modified smart tag with 3% MPGE and an additional crosslinking agent provided the best sensitivity compared with the other nanosheet compositions. The presence of 3D segregated structures on the smart tag's sensing area successfully enhanced the sensitivity performance of seepage detection in concrete structures and is expected to benefit structural health monitoring as a novel non-destructive test method.

20.
Environ Sci Pollut Res Int ; 29(32): 48620-48637, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35199268

RESUMO

The present study evaluates the performance of an indigenously developed ceramic ultrafiltration (UF) membrane in a lab-scale membrane bioreactor (MBR) process to treat real tannery effluent with varying organic loading (1500-6000 mg/L). UF membrane was prepared by the coating of bentonite clay on tubular clay-alumina macroporous support. The membrane surface was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, BET adsorption-desorption, contact angle measurement, and atomic force microscopy. In the side-stream MBR process, sewage sludge from a local sewage treatment plant was used as an activated sludge source with a constant sludge retention time of 30 days. Membrane filtration was performed in cross-flow mode using a single-channel membrane module. Artificial neural network (ANN) modeling tool was used to analyze the influence of various independent input variables, namely, the hydraulic retention time (4-10 h), mixed liquor suspended solid (MLSS) concentration (2-8 g/L), and influent COD concentration (1500-6000 mg/L) on COD removal (%) with feed-forward backpropagation method. Membrane study was done at a transmembrane pressure of 4.3 bar and feed flow rate of 7.5 L/min to observe the flux declination and fouling of the UF membrane with time. Average COD and BOD concentrations obtained in the treated effluent were 147.56 and 31 mg/L, respectively, and chromium concentration was < 0.1 mg/L; thus, treated effluent quality was found to be suitable for industrial recycling purposes apart from the safe environmental discharge. An in-depth study was undertaken to understand the removal mechanism in the MBR process, nature and extent of membrane fouling, changes in the morphology of the UF membrane, surface wettability, and surface topology by detailed surface characterization of the membrane pre- and post-filtration.


Assuntos
Ultrafiltração , Purificação da Água , Reatores Biológicos , Cerâmica , Argila , Membranas Artificiais , Esgotos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos
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