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A weld is the main connection form of special equipment, and a weld is also the most vulnerable part of special equipment. Therefore, an effective detection of a weld is of great significance to improve the safety of special equipment. The traditional inspection method is not only time-consuming and labor-intensive, but also expensive. The welding seam tracking and inspection robot can greatly improve the inspection efficiency and save on inspection costs. Therefore, this paper proposes a welding seam tracking and inspection robot based on YOLOv8s-seg. Firstly, the MobileNetV3 lightweight backbone network is used to replace the backbone part of YOLOv8s-seg to reduce the model parameters. Secondly, we reconstruct C2f and prune the number of output channels of the new building module C2fGhost. Finally, in order to make up for the precision loss caused by the lightweight model, we add an EMA attention mechanism after each detection layer in the neck part of the model. The experimental results show that the accuracy of weld recognition reaches 97.8%, and the model size is only 4.88 MB. The improved model is embedded in Jetson nano, a robot control system for seam tracking and detection, and TensorRT is used to accelerate the reasoning of the model. The total reasoning time from image segmentation to path fitting is only 54 ms, which meets the real-time requirements of the robot for seam tracking and detection, and realizes the path planning of the robot for inspecting the seam efficiently and accurately.
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The regular detection of weld seams in large-scale special equipment is crucial for improving safety and efficiency, and this can be achieved effectively through the use of weld seam tracking and detection robots. In this study, a wall-climbing robot with integrated seam tracking and detection was designed, and the wall climbing function was realized via a permanent magnet array and a Mecanum wheel. The function of weld seam tracking and detection was realized using a DeepLabv3+ semantic segmentation model. Several optimizations were implemented to enhance the deployment of the DeepLabv3+ semantic segmentation model on embedded devices. Mobilenetv2 was used to replace the feature extraction network of the original model, and the convolutional block attention module attention mechanism was introduced into the encoder module. All traditional 3×3 convolutions were substituted with depthwise separable dilated convolutions. Subsequently, the welding path was fitted using the least squares method based on the segmentation results. The experimental results showed that the volume of the improved model was reduced by 92.9%, only being 21.8 Mb. The average precision reached 98.5%, surpassing the original model by 1.4%. The reasoning speed was accelerated to 21 frames/s, satisfying the real-time requirements of industrial detection. The detection robot successfully realizes the autonomous identification and tracking of weld seams. This study remarkably contributes to the development of automatic and intelligent weld seam detection technologies.
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During zinc hydrometallurgy process, the chloride ions in the materials go into the leaching solution, which have abominable effects on equipment, electrowinning, and environment. So, it is necessary to remove chloride ions from zinc sulfate solution. The present review outlines the current research of removal methods of chlorine by holistically highlighting the advantages and mechanisms. The main techniques used to remove chloride ions from zinc sulfate solution are also discussed in detail. Among the methods, the precipitation method using copper slag to remove chlorine is widely used and the chlorine removal rate is up to 98%. In addition, the combination of electrochemistry and nanofiltration technology can form a closed-loop production process with less waste output and near-zero emissions. In addition, the challenges and possible future directions of chlorine removal from zinc sulfate solutions are also delineated.
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Cloro , Cobre , Cloretos , Zinco , Sulfato de ZincoRESUMO
The existence of sulfur dioxide and water vapor in the flue gas generated from waste-to-energy stations could lead to catalyst deactivation, which has adverse effects on NOx removal. It is thus particularly important to study the reaction mechanism of catalyst resistance to poisoning. Herein, we report the mechanism of In-Co3O4-Ga2O3/H-Beta catalyst to SO2 and H2O resistance in the selective catalytic reduction (SCR) of NOx by CH4. The catalyst could achieve 74.6% NOx removal efficiency in the presence of 100 ppm SO2 and 5% H2O. In this catalyst, Co3O4 is attributed to enhancing the reversible poisoning of SO2 and CH4 activation and increasing the number of Brønsted acid sites by decomposing H2O. However, the InO+ active center was still eroded by a small amount of water vapor, leading to a reduction in NOx removal efficiency. The addition of Ga2O3 primarily provided an important intermediate NO2 for CH4-SCR reaction and reduced the aggregates of Co3O4 to increase the exposure of indium sites, and could reduce a part of SO2 to S2-. This study provides a good candidate for preparing catalysts with superior resistance towards SO2 and H2O for CH4-SCR.
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Amônia , Vapor , Catálise , Cobalto , Oxirredução , ÓxidosRESUMO
Background: Long non-coding RNAs (lncRNAs) have been implicated in the pathogenesis of atherosclerosis. LncRNA OIP5 antisense RNA 1 (OIP5-AS1) has been found to be associated with the development of atherosclerosis. In this study, we further investigated the molecular basis of OIP5-AS1 in atherosclerosis pathogenesis. Methods: Oxidative low-density lipoprotein (ox-LDL) was used to treat human umbilical vein endothelial cells (HUVECs). The levels of OIP5-AS1, miR-135a-5p, and Krüppel-like factor 5 (KLF5) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell viability, migration, and apoptosis were evaluated using the Cell Counting Kit-8 (CCK-8), Transwell, and flow cytometry, respectively. The levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and malondialdehyde (MDA) were determined with enzyme-linked immunosorbent assay (ELISA). Targeted interactions among OIP5-AS1, miR-135a-5p, and KLF5 were confirmed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Animal studies were performed to assess the role of OIP5-AS1 in atherosclerosis progression in vivo. Results: Our data showed the significant upregulation of OIP5-AS1 in atherosclerosis serum and ox-LDL-stimulated HUVECs. The silencing of OIP5-AS1 protected against ox-LDL-triggered cytotoxicity in HUVECs and diminished lipids secretion in ApoE-/- mice. Moreover, OIP5-AS1 functioned as a molecular sponge of miR-135a-5p, and miR-135a-5p was a functional mediator of OIP5-AS1 in regulating ox-LDL-induced HUVEC injury. KLF5 was a direct target of miR-135a-5p, and the increased expression of miR-135a-5p alleviated ox-LDL-induced cytotoxicity by downregulating KLF5. Furthermore, OIP5-AS1 influenced KLF5 expression through sponging miR-135a-5p. Conclusion: The current work identified that the silencing of OIP5-AS1 protected against ox-LDL-triggered cytotoxicity in HUVECs at least in part by influencing KLF5 expression via acting as a miR-135a-5p sponge.
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A novel metal-organic framework (UiO-66-PTC) for efficient removal of Pb2+ ions from wastewater has been prepared by using 4-phenyl-3-thiosemicarbazide as the modifier. Various characterizations showed that UiO-66-PTC was successfully synthesized. The absorption results showed that the maximum adsorption capacity of Pb(II) is 200.17 mg/g at 303 K and optimal pH 5. The adsorption kinetic follows the pseudo-second-order model and the adsorption isotherms fit the Langmuir model. This shows that Pb(II) is a single-layer adsorption on the surface of the adsorbent and the rate-controlling step is chemical adsorption. The thermodynamic results show that the adsorption process can proceed spontaneously, belong to the exothermic reaction. The adsorbent can selectively uptake lead ions from wastewater containing multiple interfering ions. After four adsorption and desorption cycles, the adsorption efficiency is still high. The adsorption mechanism of Pb(II) on the adsorbent is mainly through the chelation of Pb(II) with N and S atoms. These results indicate that UiO-66-PTC is an effective material for efficiently and selectivity removal of Pb(II) from solution, which is of practical significance.
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The recovery of gold from wastewater has received significant attention in the last years due to its high economic value and low availability. A novel chitosan-based adsorbent (CS-GTU) was successfully synthesized by using formaldehyde as a crosslinker between chitosan and guanylthiourea, and applied for selective adsorption of AuIII from an aqueous medium. Through batch experiments, the maximum adsorption capacity of CS-GTU for AuIII could reach up to 695.63 mg/g at pH 5.0, and the adsorption process followed the Pseudo-second-order kinetic and Langmuir isotherm models, indicating that the monolayer chemisorption possibly occurred on the adsorbent surfaces. The adsorption was an enthalpy driven and spontaneous chemical process based on thermodynamic analysis. Furthermore, the adsorbent has demonstrated outstanding selectivity toward AuIII from multi-metallic solutions, and five cycled experiments of adsorption-desorption showed that CS-GTU could be efficiently regenerated. Experimental breakthrough curves were successfully simulated by using the Thomas model, which can fit the experimental data with the correlated curve (R2 > 0.9) well. This improvement in adsorption was a consequence of the complexation and electrostatic attraction of gold ions with the abundant sulfur/nitrogen-containing groups. The CS-GTU beads can be considered as a suitable and efficient adsorbent for gold ions in aqueous solutions.
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Quitosana/química , Formaldeído/química , Ouro/isolamento & purificação , Guaniltioureia/química , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Reagentes de Ligações Cruzadas/química , Humanos , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica , Purificação da Água/métodosRESUMO
An outstanding metal-organic framework sorbent (Zn-MOF) was prepared using Zn2+ and 3-amino-5-mercapto-1,2,4-triazole to eliminate toxic metal ions from water. Zn-MOF was detected via using Fourier-transform infrared (FTIR) spectroscopy, field-emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller (BET) analysis, and X-ray photoelectron spectroscopy (XPS). Zn-MOF is stable and has a very large surface area. The uptake properties of Zn-MOF were investigated. The maximum uptake capacity of Zn-MOF for Pb, Hg, and As ions was 1097, 32, and 718 mg/g, respectively. This was obtained at pH = 4, 5, and 6, respectively. The adsorption data is in good agreement with the Langmuir and pseudo-second-order rate models, indicating that the uptake process of Zn-MOF for toxic metal ions was a single layer uptake on a uniform surface via exchange of valence electrons. Thermodynamics shows that the uptake process is autogenic and endothermic. Zn-MOF can be reused at least 6 times. Mercury and lead strongly coordinated with Zn-MOF. The interaction between arsenic and Zn-MOF is weak chemical coordination and ion exchange. Zn-MOF has wide application prospects for toxic metal ion elimination.
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MicroRNA-134-5p (MiR-134-5p) has been proposed as a promising novel biomarker for the diagnosis of acute myocardial infarction (AMI). However, the biological role of miR-134-5p in ischemic cardiomyocytes has been little disclosed yet. Expression of miR-134-5p and X-linked inhibitor of apoptosis protein (XIAP) was detected using RT-qPCR and western blot. Oxidative stress and cell apoptosis were determined by enzyme-linked immunosorbent assays, 3-(4, 5-dimethylthiazole-2-y1)-2, 5-biphenyl tetrazolium bromide assay, flow cytometry, western blot, and terminal-deoxynucleoitidyl transferase-mediated nick end labeling (TUNEL). The interaction between miR-134-5p and XIAP was confirmed by luciferase reporter assay. Expression of miR-134-5p was upregulated in serum of AMI patients and hypoxia/reoxygenation (H/R)-induced cardiomyocytes (AC16 and HCM). MiR-134-5p downregulation could inhibit H/R-mediated release of lactic dehydrogenase enzyme (LDH) and malondialdehyde (MDA), and promote superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) levels. Meanwhile, cell viability was increased, while the apoptosis rate and TUNEL positive cells were inhibited by miR-134-5p downregulation in H/R-treated AC16 and HCM cells. Mechanically, XIAP was downregulated and targeted by miR-134-5p in H/R-induced cardiomyocytes in vitro. Overexpression of XIAP inhibited oxidative stress and cell apoptosis in H/R-treated AC16 and HCM cells, which was similar to miR-134-5p knockdown. Moreover, downregulation of XIAP could partially reverse the effect of miR-134-5p knockdown in H/R-induced cardiomyocytes. Knockdown of miR-134-5p protected cardiomyocytes from H/R-induced oxidative stress and apoptosis in vitro through targeting XIAP.
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MicroRNAs/sangue , MicroRNAs/genética , Infarto do Miocárdio/genética , Traumatismo por Reperfusão Miocárdica/patologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Idoso , Hipóxia Celular/genética , Linhagem Celular , Regulação para Baixo , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Traumatismo por Reperfusão Miocárdica/genética , Miócitos Cardíacos/patologia , Miócitos Cardíacos/fisiologia , Estresse Oxidativo/genética , Regulação para Cima , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismoRESUMO
AIM: The imbalance of T helper (Th) 17/T regulatory (Treg) is involved in chronic heart failure (HF). The enzyme lysyl oxidase (LOX) contributes to myocardial fibrosis. This study was designed to decipher the regulatory mechanism of Th17/Treg on LOX expression and to validate whether Th17/Treg imbalance regulates myocardial fibrosis by modulating LOX expression. METHODS: Human cardiac fibroblasts (HCFs) were treated with angiotensin II (Ang II) and co-cultured with Th17 cells and Tregs which were polarized from control naïve CD4+ T cells. Th17 cells and Tregs were adoptively transferred into abdominal aortic coarctation-induced chronic HF rats to investigate the efficacy of Th17 and Treg infusions on myocardial fibrosis and HF. RESULTS: Th17/Treg imbalance (increased Th17 cells and decreased Tregs) was observed in HF patients. Th17 cells/Tregs aggravated/attenuated Ang II-induced upregulation of LOX and fibrosis-related indicators (MMP-2/9 and collagen I/III) in HCFs in vitro and abdominal aortic coarctation-induced myocardial fibrosis and HF in rats, by promoting/inhibiting LOX expression. Mechanistically, Th17 cells promoted LOX expression by activating the IL-17/ERK1/2-AP-1 pathway, while Tregs inhibited LOX expression by activating the IL-10/JAK1-STAT3 pathway. CONCLUSION: Increased Th17 cells and decreased Tregs aggravate myocardial fibrosis and HF by inducing LOX expression.
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Insuficiência Cardíaca , Células Th17 , Animais , Fibrose , Humanos , Proteína-Lisina 6-Oxidase , Ratos , Linfócitos T ReguladoresRESUMO
Mercury ions can cause a series of hazards to humans and the environment, even in trace amounts. Here, we designed a novel adsorbent (Cys-UiO-66) by functionalizing NH2-UiO-66 with l-cysteine for selective removal of Hg(II) from solution. The Cys-UiO-66 was characterized by different instruments. The adsorption property of Cys-UiO-66 was evaluated by batch methods. The maximum adsorption capacity was 350.14 mg/g at pH 5.0. Furthermore, the adsorption isotherm and kinetics models were in accord with the Langmuir and pseudo-second-order models, respectively, evidencing that the adsorption behavior was dominated by monolayer chemisorption. The Cys-UiO-66 had better affinity for Hg(II) than other coexisting ions in wastewater and could be regenerated for at least five cycles. The results prove that Cys-UiO-66 is a talented and efficient sorbent for mercury ions.
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A novel magnetic chitosan adsorbent (CDF-CS) was synthesized by inserting magnetic particles into the crosslinked compound of chitosan (CS) and cystamine based on one-step method for selectively recovering Au(III) from aqueous solution. The characterization and adsorption mechanism of CDF-CS were studied by SEM-EDS, VSM, FT-IR and XPS, respectively. The experimental results show that the adsorption capacity of CDF-CS is still large in a wide range of pH values (from 1 to 7) and has a higher adsorption capacity for Au(III) than the raw chitosan, the maximum adsorption capacity of CDF-CS for Au(III) was 478.47â¯mg/g about 6â¯h at pHâ¯=â¯7.0. The adsorption behavior is most consistent with this pseudo-second-order kinetic model. The adsorption process of gold ions by CDF-CS follows the Langmuir adsorption isotherm. Furthermore, the thermodynamic parameter indicates that the adsorption reaction of gold ions by CDF-CS is an endothermic chemisorption. CDF-CS has great potential for removing gold ions from aqueous solutions due to the excellent repeatability and selectivity. Finally, the adsorption mechanism is that chelation reaction and ion exchange mainly occurred between CDF-CS and Au(III). Therefore, CDF-CS is very promising in recovery of Au(III) from aqueous solutions.