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Metal-organic framework (MOF) and MOF-derived materials have attracted extensive research interest as environmental catalysts. In this study, a composite material (ZIF-67/CCot-8) was successfully prepared using cotton fiber as a substrate and growing ZIF-67 in situ. This material exhibited excellent catalytic performance and significantly improved the efficiency of antibiotics degradation. ZIF-67/CCot-8 at a concentration of 0.05 g/L, combined with 0.2 mM peroxymonosulfate (PMS), removed approximately 97% of ciprofloxacin (CIP) and 99% of tetracycline and sulfamethoxazole within 15 min. The high catalytic efficiency of this catalyst is mainly attributed to the uniform distribution of ZIF-67-derived nanoparticles on the surface of the cotton fibers, providing abundant active sites and thereby significantly enhancing the efficiency of antibiotics degradation. Radical quenching experiments and electron paramagnetic resonance (EPR) analyses revealed that sulfate radicals (SO4â¢-) and singlet oxygen (1O2) were the main active species. Mass spectrometry (MS) was used to elucidate the CIP degradation pathway. The growth of the roots and stems of soybean sprouts in different water environments (tap water, treated water, and untreated water) was also observed. The results demonstrated a significant improvement in the inhibition of plant growth in the post-degradation CIP solution, indicating a substantial reduction in the toxicity of the degraded aqueous solution. To validate the practicality of the ZIF-67/CCot-8/PMS system, a continuous-flow water-treatment device was designed. This system removed 98% of the CIP solution within 180 min, demonstrating its excellent durability. This study presents a potential pathway for effective antibiotics removal using MOF-derived materials.
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Ciprofloxacina , Peróxidos , Ciprofloxacina/química , Peróxidos/química , Agua , AntibacterianosRESUMEN
The sluggish Ni(II)/Ni(III) redox cycle does not benefit perxymonosulfate (PMS) activation for recalcitrant pollutant degradation. To solve this problem, a heterogeneous catalyst, Cu0.2Ni0.8O/SBA-15 (CNS), was constructed to activate PMS for decomposing two sulfonamide antibiotics, sulfachlorpyridazine (SACP) and sulfapyridine (SAP). SACP and SAP were completely degraded over Cu0.2Ni0.8O/SBA-15/PMS (CNSP) after 90 min. O2.- was the dominant active species involved in the degradation of SACP and SAP. Structural analysis and elemental valence state observations indicated that Cu(â ) provided electrons through Cu-O-Ni bonds to realize the charge compensation for Ni(â ¢) in the CNSP system. Thus, the in situ Cu(I)/Cu(II) promoting the Ni(II)/Ni(III) cycle could accelerate the PMS activation. This work provides new insights into the electron transfer between transition metals and the charge compensation mechanism for PMS activation. The degradation mechanism was proposed based on the XPS results before and after the reaction, a radical quenching test, and an EPR test. Combined with the SACP and SAP degradation intermediates identified by LC-MS, we suggest that the choice of treatment process depends on the occurrence of a steric hindrance effect between the molecular structure of the degradation target and free radicals.
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Antibacterianos , Cobre , Cobre/química , Níquel , Peróxidos , Dióxido de Silicio , SulfonamidasRESUMEN
The largest source of resistant bacteria or viruses is the overuse and misuse of antibiotics in humans and animals. These resistant bacteria or viruses may evolve into superbacteria or superviruses, which causes global plague. Therefore, it is significant to find a highly efficiency and low-cost method to eliminate antibiotics in water environment from inappropriate discharge. Here, a highly active and highly stable heterogeneous catalyst, Cu0.76Co2.24O4/SBA-15 (CCS) was prepared for peroxymonosulfate (PMS) activation in aim of decomposing persistent sulfapyridine (SPD). The reaction mechanism was thoroughly investigated via in situ quenching test and in situ electron paramagnetic resonance. Four reactive species, SO4·-, O2·-, 1O2 and ·OH were generated in Cu0.76Co2.24O4/SBA-15/PMS (CCSP) system. The SO4·- and O2·- were dominant active species responsible for SPD degradation. Co(â ¡)âCo(â ¢)âCo(â ¡) redox reaction cycle was constructed due to the different redox potential of Co(â ¡)/Co(â ¢), HSO5-/SO4â-, and HSO5-/SO5â-. Interestingly, Cu(â ) could urge the redox reaction cycle for PMS activation to be more thermodynamically feasible. Therefore, CCS possessed a highly catalytic activity and excellent stability. Meanwhile, the anions interference test indicated Cl-, NO3-, HCO3-, and H2PO4- had almost no inhibitory effect on SPD degradation over this catalytic system. We sincerely expected that this catalyst system would be applied extensively into antibiotics degradation in real water bodies.
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Metal-organic frameworks (MOFs) are emerging class of porous materials that attracted tremendous attention as eco-friendly photocatalysts. However, poor charge separation in most MOFs largely thwarts their photocatalytic performance. In this work, Materials of Institut Lavoisier-100(Fe) (MIL-100 (Fe)) based on iron mesh was successfully fabricated by in situ growth. MIL-100(Fe) doped with polyaniline, namely MIL-100(Fe)/PANI, were then fabricated by galvanostatic deposition followed by annealing. Compared to pure MIL-100(Fe), MIL-100(Fe)/PANI composites exhibited excellent photocatalytic performances towards Thiamphenicol (TAP) degradation and Escherichia coli (E. Coli.) inactivation. The apparent rate constant, k, for TAP elimination of the MIL-100(Fe)/PANI composites with H2O2 is approximately 3 times as high as that of pure MIL-100(Fe). The electrochemical studies showed enhanced photocatalytic performances, which can be attributed to the electronic conductivity of PANI polymers. Quenching experiments, fluorescent tests and electron paramagnetic resonance (EPR) all suggested â O2-, e-, â OH and h+ as reactive oxidizing species (ROSs) involved in the photocatalytic process, where â OH played the predominant ROSs. The transformation products of TAP were also isolated and characterized by high-resolution mass spectrometry, and transformation pathways of TAP under Vis/MIL-100(Fe)/PANI/H2O2 were tentatively clarified based on involved intermediates. Herein, MOFs conjugated conductive polymers nanocomposites look promising as efficient photocatalysts for organic pollutants degradation and bacteria inactivation. This work could offer novel strategies for the development of heterojunction composites with enhanced photocatalytic performances for better environmental remediation.
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Estructuras Metalorgánicas , Tianfenicol , Escherichia coli , Peróxido de Hidrógeno , HierroRESUMEN
Propyl paraben (propyl 4-hydroxybenzoate, PPB), one of the typically used paraben species in various pharmaceutical and personal care products, has been found in different aquatic environment, which could affect the water quality and human health. In this paper, the degradation of PPB by aqueous ferrate (Fe(VI)) was investigated in different water matrix and reaction kinetics as a function of pH was determined. Intermediate products of the degradation process were isolated and characterized by the high performance liquid chromatography/mass spectrometry/mass spectrometry techniques. Acute and chronic toxicities during water treatment of PPB using Fe(VI) were calculated using the ECOSAR program at three trophic levels. The obtained apparent second-order rate constant (kapp) for PPB reaction with Fe(VI) ranged from 99.6 ± 0.4 M-1 s-1 to 15.0 ± 0.1 M-1 s-1 with the half-life (t1/2) ranging from 154 s to 1026 s at pH 6.5-10.0 for an Fe(VI) concentration of 600 µM. The proposed pathway for the oxidation of PPB by Fe(VI) involves one electron transfer of phenoxyl radical and breaking of the ether bond. In general, the oxidation of PPB by ferrate resulted in a significant decrease in toxicity at three trophic levels.
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Hierro/farmacocinética , Parabenos/farmacocinética , Parabenos/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidad , Animales , Cromatografía Líquida de Alta Presión , Humanos , Hierro/química , Hierro/toxicidad , Cinética , Oxidación-Reducción , Parabenos/química , Fenoles/química , Fenoles/farmacocinética , Fenoles/toxicidad , Medición de Riesgo , Espectrometría de Masas en Tándem , Pruebas de Toxicidad , Contaminantes Químicos del Agua/química , Purificación del Agua/métodosRESUMEN
Phosphorus is an indispensable and irreplaceable element in the ecosystem. Based on the ability of ferrate(VI) to remove phosphate by producing iron phosphate, a new method for using ferrate(VI) to treat hypophosphite has been studied. In this study, ferrate was added to the hypophosphate solution in a controlled manner, and the oxidation efficiency of ferrate(VI) on hypophosphate was studied under various initial pH conditions, when the pH value of 6.0, the hypophosphate oxidation rate reached 14.0%. Research findings, Ferrate recovered hypophosphate through precipitation and adsorption under various initial pH conditions. To further investigate the mechanism of hypophosphate recovery, the morphology and microstructure of the deposition were analysed using Fourier transform infrared, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The kinetic process of ferrate recovery from hypophosphate was analysed. The recovery process follows second-order reaction kinetics, and the reaction rate is highest at pH 6.0. The value of kA1 is 1.742 × 10-2. This study shows that ferrate (VI) is a promising treatment tool for low-cost phosphate wastewater. Furthermore, this method offers a clean phosphorus recovery process without the generation of harmful substances.
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Early diagnosis of renal cell carcinoma relies on imaging tests such as ultrasound, computed tomography, or magnetic resonance imaging. Since surgery is associated with a favorable prognosis, the standard treatment for clinically limited renal cell carcinoma remains surgical resection. Among asymptomatic patients with localized renal cell carcinoma, a small number refuse surgical treatment and survive. We report a case involving a 59-year-old female who underwent a difficult radical nephrectomy 17 years after being diagnosed with malignant tumors due to primary renal cell carcinoma.
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A reconfigurable dexterous gripper is designed which can switch states, including rigidity and flexibility, for different application scenarios. Moreover, the stiffness of the fingers in the flexible state can also be tuned for different objects. Three fingers are connected to the revolute joints of the palm, and each finger has a reshape mechanism with a slider moving up and down to lock or release the fingertip joint. When the slider moves upward, the gripper works in the rigid state and the fingers are actuated by the servos. When the slider moves downward, the gripper works in the flexible state that the fingertip is supported by a spring, and the fingertip joint is rotated by an embedded motor with two group cables for tuning stiffness. This novel design provides the gripper with the advantages of high precision and strong load capacity of rigid grippers and shape adaptability and safety of soft grippers. The reconfigurable mechanism allows the gripper great versatility for grasping and manipulation, which facilitates the planning and execution of the motion of objects with different shapes and stiffness. We discuss the stiffness-tunable mechanism with different states, analyze the kinematic characteristics, and test the manipulator performance to investigate the application in rigid-flexible collaborative works. Experimental results show the practicability of this gripper under different requirements and the rationality of this proposed concept.
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As every-one knows, cadmium contamination poses a significant and permanent threat to people and aquatic life. Therefore, research on how to remove cadmium from wastewater is essential to protect the natural environment. In this study, agricultural and forestry waste straw sprayed with selenium-enriched foliar fertilizer was prepared as biochar, which was altered by calcium chloride (CaCl2) to remove Cd2+ from water. The outcomes demonstrated that biochar generated by pyrolysis at 700 °C (BC700) had the best adsorption effect. Secondly, pseudo-second-order kinetics and Langmuir adsorption models were used to predict the Cd2+ adsorption. Finally, electrostatic adsorption, ion exchange, and complexation of oxygen functional groups (OFGs) were demonstratedto be the main adsorption mechanisms. These conclusions indicate that selenium-rich straw biochar is a novel adsorbent for agroforestry waste recovery. Meanwhile, this work will offer a promising strategy for the overall utilization of rice straw.
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Selenio , Contaminantes Químicos del Agua , Humanos , Cadmio , Cloruro de Calcio , Adsorción , Carbón Orgánico , Contaminantes Químicos del Agua/análisis , CinéticaRESUMEN
Material-enhanced heterogeneous peroxymonosulfate (PMS) activation for degradation of antibiotic in water has attracted intensive attention. However, one challenge is the electron transfer efficiency from the material to PMS for reactive oxygen species (ROS) production. Considering that the B-sites of perovskite oxides are closely associated with the catalytic performance, partial substitution of the B-sites of perovskite oxides can enhance the redox cycle of metals. Consequently, adjusting the ratio of each element at the B site can introduce oxygen vacancies on the surface of perovskite. Herein, a method was developed in which manganese (Mn) partially substitutes B-sites to modify surface properties of SrCoO2.52 perovskite oxides, resulting in the enhancement of catalytic activity. In degradation kinetics studies using SrCoMnO3-δ-0.5/PMS (SrCoMnO3-δ-0.5 denotes that the molar substitution of Mn at the B site of SrCoO2.52 perovskite oxide is 0.5) reaction system and sulfamethoxazole (SMX) as the target pollutant, it was found that the reaction rate constant (kobs) is 0.287 min-1 which is 2.4 times that of SrCoO2.52/PMS system. Experimental and theoretical analyses revealed that Mn-O covalent bonding governs the intrinsic catalytic activity of SrCoMnO3-δ-0.5 perovskite oxides. The Mn sites exhibits stronger adsorption energy with PMS than the Co sites, facilitating the breaking of O-O bond. Simultaneously, oxygen vacancies and surface adsorbed oxygen species have a synergistic effect for PMS adsorption. This work can provide a potential route in developing advanced catalysts based on manipulation of the B-sites of perovskite oxides for PMS activation.
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Contaminantes Ambientales , Manganeso , Especies Reactivas de Oxígeno , Peróxidos/química , Óxidos/química , Sulfametoxazol/química , Oxígeno , Agua , AntibacterianosRESUMEN
In the dinuclear title complex, [Cu(2)(C(30)H(38)N(4)O(2))(H(2)O)(2)](ClO(4))(2), the coordination cation has crystallographically imposed twofold rotational symmetry. The Cu(II) ion is five-coordinated by two N and two O atoms from the macrocylic ligand and one O atom from a water mol-ecule, forming a square-pyramidal N(2)O(3) geometry with the water mol-ecule in the apical position. The distance between the two Cu(II) atoms is 3.0930â (5)â Å. Hydrogen bonds between water mol-ecules and between water mol-ecules and perchlorate anions assemble two cations and four anions into discrete supermolecules of S(4) symmetry. Intramolecular O-Hâ¯N hydrogen bonds are also observed. The perchlorate anion and the tert-butyl group are disordered over two positions, with occupancies of the major positions of 0.527â (11) and 0.592â (9), respectively.
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The papaya leaves were extracted via ultra-pure water. The obtained papaya leaves extract (PLE) was used as the eco-friendly inhibitor for Cu in the H2SO4 corrosion medium. The experimental results showed that PLE was a mixed-type inhibitor and exhibited excellent anti-corrosion nature over a certain temperature range. Morphological analysis test results at different temperatures strongly proved the anti-corrosion nature of PLE. The XPS test results found that an adsorption film of Cu-S bond and Cu-N bond was formed on the Cu surface. This barrier film conformed to Langmuir mono-layer adsorption. Corrosion kinetics and thermodynamic parameters were calculated and discussed.
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Carica , Corrosión , Extractos Vegetales , Hojas de la Planta , AceroRESUMEN
PURPOSE: To establish and validate a regional lymph node (LN) metastasis prediction model of colorectal cancer (CRC) based on 18F-FDG PET/CT and radiomic features using machine-learning methods. METHODS: A total of 199 colorectal cancer patients underwent pre-therapy diagnostic 18F-FDG PET/CT scans and CRC radical surgery. The Chang-Gung Image Texture Analysis toolbox (CGITA) was used to extract 70 PET radiomic features reflecting 18F-FDG uptake heterogeneity of tumors. The least absolute shrinkage and selection operator (LASSO) algorithm was used to select radiomic features and develop a radiomic signature score (Rad-score). The training set was used to establish five machine-learning prediction models and the test set was used to test the efficacy of the models. The effectiveness of the models was compared by ROC analysis. RESULTS: The CRC patients were divided into a training set (n = 144) and a test set (n = 55). Two radiomic features were selected to build the Rad-score. Five machine-learning algorithms including logistic regression, support vector machine (SVM), random forest, neural network and eXtreme gradient boosting (XGBoost) were used to established models. Among the five machine-learning models, logistic regression (AUC 0.866, 95% CI 0.808-0.925) and XGBoost (AUC 0.903, 95% CI 0.855-0.951) models performed the best. In the training set, the AUC of these two models were significantly higher than that of the LN metastasis status reported by 18F-FDG PET/CT for differentiating positive and negative regional LN metastases in CRC (all p < 0.05). Good efficacy of the above two models was also achieved in the test set. We created a nomogram based on the logistic regression model that visualized the results and provided an easy-to-use method for predicting regional LN metastasis in patients with CRC. CONCLUSION: In this study, five machine-learning models for preoperative prediction of regional LN metastasis of CRC based on 18F-FDG PET/CT and PET-based radiomic features were successfully developed and validated. Among them, the logistic regression and XGBoost models performed the best, with higher efficacy than 18F-FDG PET/CT in both the training and test sets.
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Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/patología , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Metástasis Linfática , Masculino , Persona de Mediana EdadRESUMEN
In this paper, the simple and low-cost water extraction way was used to acquisition Betel leaves extracts (BLE). The water as the extraction solvent has the characteristics of low price, environmentally friendly, and good solubility for other extraction solvents. BLE was researched as an environmental-friendly inhibitor via various experimental methods and theoretical calculations. Electrochemical experiments manifest that BLE can restrain reactions of the cathode and anode of Q235 steel. The BLE concentration was 400 mg/L, the anti-corrosion efficiency was close to 94%. The experimental data show that BLE can show high-quality anti-corrosion nature for Q235 steel immersing in 1 M hydrochloric acid (HCl) environment at a certain temperature range. The morphology maps of scanning electron microscope (SEM) and atomic force microscopy (AFM) strongly proves the data of electrochemical experiments. In addition, the BLE adsorption at the Q235 steel surface belongs to the Langmuir mono-layer adsorption. Quantum chemical calculations (QCC) and molecular dynamics simulations (MDS) effectually manifest that BLE can show decent anti corrosion character.
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Acero , Agua , Adsorción , Corrosión , Hojas de la PlantaRESUMEN
By using cyclic voltammetry method, L-histidine and erythrosine was electrodeposited on the surface of glassy carbon electrode (GCE) to obtain the modified electrode (denoted as L-His-Erythrosine/GCE). The morphology of L-His-Erythrosine/GCE was characterized by scanning electron microscopy (SEM), and the electrochemical property characterization of L-His-Erythrosine/ GCE was investigated using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. The electrocatalytic oxidation of hydroquinone (HQ) and catechol (CC) on the modified electrode was discussed by differential pulse voltammetry (DPV) in this study. The L-His-Erythrosine/GCE had shown an excellent electrocatalytic activity for HQ and CC. The oxidation overpotentials of HQ and CC decreased significantly and the corresponding oxidation currents increased remarkably. Due to the large separation of oxidation peak potentials (108 mV), concentrations of HQ and CC can be easily determined simultaneously. Under the optimum conditions, the oxidation peak currents for both HQ and CC increased linearly with the respective concentrations in the 1.2 x 10(-6) to 1.1 x 10(-4) mol x L(-1) concentration range, with the detection limits of 0.19 and 0.16 µmol x L(-1) (S/N = 3), respectively. Furthermore, the modified electrode exhibited good reproducibility and selectivity. The modified electrode was successfully applied to the simultaneous determination of HQ and CC in actual water samples, the recoveries got by standard addition method were in ranges of 99.9% - 100.6% (HQ) and 99.2% - 100.2% (CC).
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Catecoles/análisis , Eritrosina/química , Histidina/química , Hidroquinonas/análisis , Carbono , Electrodos , Oxidación-Reducción , Reproducibilidad de los ResultadosRESUMEN
The efficacy of Extracorporeal Shock Wave Lithotripsy (ESWL) depends greatly on the capability to focus shock waves on renal stone. To achieve automatic focusing on moving target, the target must be under tracking. A mesh-based block matching algorithm is proposed for renal stone tracking using ultrasound image sequence. Since multiple targets are tracked together, the mesh-based tracking algorithm can provide a function of contextual regularization for solving the target missing and image degradation problems in renal stone tracking. Recorded ultrasound images of kidney during ESWL treatment are modified for demonstrating the capability of this algorithm.