ABSTRACT
A lightning current measurement method using a Rogowski coil based on an integral circuit with low-frequency attenuation feedback was proposed to address the issue of low-frequency distortion in the measurement of lightning currents on transmission lines using Rogowski coils. Firstly, the causes of low-frequency distortion in lightning current measurements using Rogowski coils were analyzed from the perspective of frequency domains. On this basis, an integration correction optimization circuit with a low-frequency attenuation feedback network was designed to correct the low-frequency distortion. The optimized integration circuit can also reduce the impact of low-frequency noise and the DC bias of the operational amplifier (op-amp) on the integration circuit due to the high low-frequency gain. Additionally, a high-pass filtering and voltage-divided sampling circuit has been added to ensure the normal operation of the integrator and improve the measurement range of the measurement system. Then, according to the relationship between the amplitude-frequency characteristics of the measurement system and the parameters of each component, the appropriate types of components and op-amp were selected to expand the measurement bandwidth. Finally, a simulation verification was conducted, and the simulation results show that this measurement method can effectively expand the lower measurement frequency limit to 20 Hz, correct the low-frequency distortion caused by Rogowski coils measuring lightning currents on transmission lines, and accurately restore the measured lightning current waveform.
ABSTRACT
Fluorinated ionic liquids (ILs) are well-known as electrolytes in the nitrogen (N2) electroreduction reaction due to their exceptional gas solubility. However, the influence of fluorinated functional group on N2 solvation and solubility enhancement remains unclear. Massive molecular dynamics simulations and free energy perturbation methods are conducted to investigate the N2 solubility in 11 traditional and 9 fluorinated ILs. It shows that the fluorinated IL of 1-Ethyl-3-methylimidazolium tris(pentafluoroethyl) trifluorophosphate ([Emim]FAP) exhibits ultrahigh solubility, 4.844 × 10-3, approximately 118 times higher than that of traditional IL 1-Ethyl-3-methylimidazolium nitrate ([Emim]NO3). Moreover, fluorinated ILs with more than 10 C-F bonds possess higher N2 solubility than others and show an exothermic nature during solvation. As the C-F bonds number in ILs decreases, the N2 solubility decreases significantly and displays the opposite endothermic behavior. To understand the ultrahigh N2 solubility in fluorinated ILs, we propose a concept of fluorine densification energy (FDE), referring to the average strength of interaction between atoms per unit volume in ILs with fluorine domains, demonstrating a linear relationship with C-F bonds. Physically, lower FDE results in lower N2-anion pair dissociation energy and higher free volume, finally enhancing the N2 solubility. Consequently, medium to long alkyl fluorine tails within a polar environment defines a distinct fluorine domain, emphasizing FDE's role in enhancing N2 solubility. Overall, these quantitative results will not only deepen the understanding of N2 solvation in ILs but may also shed light on the rational design of IL-based high-performance N2 capture and conversion technologies.
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Conventional static cold storage (SCS) exacerbates ischemic injury in the DCD liver, leading to severe complications for transplant recipients. To address this issue, clinical application of MP technology for donor liver preservation is underway. Simultaneously, efforts are focused on the development of various MP instruments, validated through relevant animal model experiments. Effective large animal trials play a pivotal role in clinical applications. However, challenges persist in the ex vivo preservation of DCD livers and the transplantation procedure in pigs. These hurdles encompass addressing the prolonged preservation of donor livers, conducting viability tests, alleviating ischemic injuries, and shortening the anhepatic phase. The use of a variable temperature-controlled MP device facilitates the prolonged preservation of DCD livers through sequential Dual Hypothermic Oxygenated Machine Perfusion (DHOPE) and Normothermic Machine Perfusion (NMP) modes. This protocol enhances the porcine OLTx model by improving the quality of DCD livers, optimizing the anastomosis technique, and reducing the duration of the anhepatic phase.
Subject(s)
Liver Transplantation , Liver , Organ Preservation , Perfusion , Animals , Liver Transplantation/methods , Organ Preservation/methods , Swine , Perfusion/methods , Liver/surgeryABSTRACT
Lithium metal batteries (LMBs), with high energy densities, are strong contenders for the next generation of energy storage systems. Nevertheless, the unregulated growth of lithium dendrites and the unstable solid electrolyte interphase (SEI) significantly hamper their cycling efficiency and raise serious safety concerns, rendering LMBs unfeasible for real-world implementation. Covalent organic frameworks (COFs) and their derivatives have emerged as multifunctional materials with significant potential for addressing the inherent problems of the anode electrode of the lithium metal. This potential stems from their abundant metal-affine functional groups, internal channels, and widely tunable architecture. The original COFs, their derivatives, and COF-based composites can effectively guide the uniform deposition of lithium ions by enhancing conductivity, transport efficiency, and mechanical strength, thereby mitigating the issue of lithium dendrite growth. This review provides a comprehensive analysis of COF-based and derived materials employed for mitigating the challenges posed by lithium dendrites in LMB. Additionally, we present prospects and recommendations for the design and engineering of materials and architectures that can render LMBs feasible for practical applications.
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Introduction: Lysinuric protein intolerance (LPI) is a rare genetic disorder caused by mutations in the solute carrier family 7A member 7 (SLC7A7) gene. Case presentation: We presented two siblings with LPI, carrying novel mutations of c.776delT (p.L259Rfs*18) and c.155G>T (p.G52V) in SLC7A7. The younger sibling, preferring protein-rich foods, showed severe symptoms, including alveolar proteinosis, macrophage activation syndrome, severe diarrhea, and disturbance of consciousness with involuntary movements. In contrast, the elder sibling only had mild symptoms, likely due to aversion to protein-rich food since toddler age. Conclusion: LPI is a congenital genetic metabolic disease with multi-system involvement. Initiating appropriate protein-restricted diet therapy as soon as possible could help prevent the progression of LPI.
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Membrane channel proteins (MCPs) play key roles in matter transport through cell membranes and act as major targets for vaccines and drugs. For emerging ionic liquid (IL) drugs, a rational understanding of how ILs affect the structure and transport function of MCP is crucial to their design. In this work, GPU-accelerated microsecond-long molecular dynamics simulations were employed to investigate the modulating mechanism of ILs on MCP. Interestingly, ILs prefer to insert into the lipid bilayer and channel of aquaporin-2 (AQP2) but adsorb on the entrance of voltage-gated sodium channels (Nav). Molecular trajectory and free energy analysis reflect that ILs have a minimal impact on the structure of MCPs but significantly influence MCP functions. It demonstrates that ILs can decrease the overall energy barrier for water through AQP2 by 1.88 kcal/mol, whereas that for Na+ through Nav is increased by 1.70 kcal/mol. Consequently, the permeation rates of water and Na+ can be enhanced and reduced by at least 1 order of magnitude, respectively. Furthermore, an abnormal IL gating mechanism was proposed by combining the hydrophobic nature of MCP and confined water/ion coordination effects. More importantly, we performed experiments to confirm the influence of ILs on AQP2 in human cells and found that treatment with ILs significantly accelerated the changes in cell volume in response to altered external osmotic pressure. Overall, these quantitative results will not only deepen the understanding of IL-cell interactions but may also shed light on the rational design of drugs and disease diagnosis.
Subject(s)
Cell Membrane Permeability , Ion Channel Gating , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Ionic Liquids/chemistry , Ionic Liquids/metabolism , Models, Molecular , Protein Structure, Tertiary , Water/chemistry , Cell LineABSTRACT
PURPOSE: To explore the mechanism of SETDB1 inhibiting epithelial mesenchymal transition (EMT),migration and invasion in oral cancer via SOX 7 methylation. METHODS: SETDB1 and SOX7 mRNA and protein expression levels in KB cells of oral cancer and oral mucosal epithelial ATCC cells were determined by qRT-PCR and Western blot (WB). SETDB1 si-RNA was structured, then transfect into KB cells of oral cancer by liposome-mediated method. siRNA-SETDB1 was the experimental group (si-S), siRNA empty vector was the negative control group (si-N), and untransfected KB cells were the blank control group(NC). SETDB1 mRNA and protein expression levels were detected by qRT-PCR and Western blot(WB), to verify the transfection effect. The methylation levels of SOX7 were determined by pyrosequencing. The expression of N-cadherin, Vimentin, ß-catenin, and Slug proteins was detected by WB. Cell viability was measured by MTT assay, migration ability was tested by scratch healing assay, and invasion ability was tested by Transwell chamber assay. Statistical analysis was performed with SPSS 21.0 software package. RESULTS: The results of Rt-qPCR and WB showed that the SETDB1 mRNA and protein expression decreased significantly in si-S group(Pï¼0.05). Pyrosequencing test results showed that the regulation of SETDB1 could significantly reduce the SOX7 methylation rate and increased the SOX7 protein expression. WB results showed that knockdown of SETDB1 significantly inhibited the expression of EMT-related proteins N-cadherin, Vimentin, ß-catenin and Slug in oral cancer KB cells (Pï¼0.05). The results of cell functology experiments showed that knockdown of SETDB1 could significantly inhibit survival, migration and invasion of KB cells. CONCLUSIONS: Downregulation of SETDB1 could suppress EMT, migration and invasion of oral cancer cells by regulating SOX7 methylation level, providing new ideas and targets for the diagnosis and treatment of oral cancer.
Subject(s)
Mouth Neoplasms , SOXF Transcription Factors , beta Catenin , Humans , beta Catenin/genetics , beta Catenin/metabolism , Down-Regulation , Cell Line, Tumor , Vimentin/genetics , Vimentin/metabolism , Cadherins/genetics , Cadherins/metabolism , RNA, Small Interfering/metabolism , Mouth Neoplasms/genetics , Epithelial-Mesenchymal Transition , RNA, Messenger/metabolism , Methylation , Cell Movement/genetics , Cell Proliferation , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolismABSTRACT
Herein, 2-mercapto-5-benzimidazolesulfonate acid sodium salt dihydrate (MBZS)-protected gold-silver bimetallic nanoclusters, named MBZS-AuAg NCs, were synthesized. Interestingly, we found that MBZS-AuAg NCs solutions can exhibit different fluorescence color changes under sulfide stimulation. A series of modern analytical testing techniques were used to explore the interaction mechanism between MBZS-AuAg NCs and sulfide. Sulfide ions can not only cause MBZS-AuAg NCs to exhibit rich fluorescence color changes similar to those of a chameleon but also have four linear relationships between the response intensity and sulfide concentration. A wide-range sulfide fluorescence sensing platform was constructed based on four linear segments with different fluorescence color responses. This sensing platform can be directly used for the determination of S2- with a detection limit as low as 11 nM. The portable test paper based on MBZS-AuAg NCs can realize the visual and rapid detection of gaseous hydrogen sulfide with a detection limit of 100 ppb (v/v). The wide detection range of the proposed method not only allows it to be used as an alternative method for sulfide detection in environmental samples but also has potential applications in the rapid detection and early warning of hydrogen sulfide gas in industrial and mining scenarios.
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BACKGROUND: Due to the unavoidable use of cerium in daily life, the accumulation of cerium in the environment increases health risks for humans. Therefore, it is crucial to develop a chemical sensing technology for the rapid, sensitive, and selective detection of cerium ions. RESULTS: In this research work, a novel two-dimensional chain structure of a europium-based metal organic framework (Eu-MOF) [Eu2(tcpa)(Htcpa)2] was synthesized by using 3,4,5,6-tetrachloro-1,2-benzenedicarboxylic acid (H2TCPA) as the ligand and europium nitrate as the metal source. The results of powder X-ray diffraction and thermogravimetric analysis show that the synthesized Eu-MOF has excellent chemical and thermal stability. When the Eu-MOF suspension was excited by ultraviolet light at 292 nm, four fluorescence emissions were observed at 420, 595, 620 and 705 nm. It was particularly interesting that when cerium ions (Ce3+/Ce4+) were added to the Eu-MOF suspension, the fluorescence intensity at 420 nm was enhanced, while the fluorescence at 620 nm was quenched. On this basis, a ratiometric fluorescent sensor for detecting cerium ions was constructed, which has a good linear relationship in the range of 0.05-15 µM and a detection limit of 16 nM. The plausible mechanism of the change in the fluorescence characteristics of Eu-MOF caused by cerium ions was discussed in detail. Through the study of fluorescence lifetime and ultraviolet absorption, it was proven that the mechanism of Ce3+-quenching Eu-MOF fluorescence is the inner filter effect. Photoinduced electron transfer and internal filtering effects lead to fluorescence quenching at 620 nm, while redox reactions lead to fluorescence enhancement of the ligand at 420 nm. SIGNIFICANCE: The proposed ratiometric fluorescence sensor was successfully employed for the detection of cerium ions in real water samples, confirming that it can be used as an alternative method for the detection of Ce3+ and Ce4+ in environmental samples.
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Introduction: Acute necrotizing encephalopathy (ANE), a fatal subtype of infection-triggered encephalopathy syndrome (ITES), can be triggered by many systemic infections. RANBP2 gene mutations were associated with recurrent ANE. Case presentation: Here we report a 1-year-old girl with recurrent ITES and RANBP2 mutation. She was diagnosed with influenza-associated encephalopathy and made a full recovery on the first episode. After severe acute respiratory syndrome coronavirus 2 infection, the patient presented with seizures and deteriorating mental status. Brain magnetic resonance imaging revealed necrotic lesions in bilateral thalami and pons. Methylprednisolone, immunoglobulin, and interleukin 6 inhibitors were administered. Her consciousness level was improved at discharge. Nineteen cases of 2019 coronavirus disease-related ANE have been reported, of which 22.2% of patients died and 61.1% had neurologic disabilities. RANBP2 gene mutation was found in five patients, two of whom developed recurrent ITES. Conclusion: Patients with RANBP2 mutations are at risk for recurrent ITES, may develop ANE, and have a poor prognosis after relapse.
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Nowadays, it is still elusive and challenging to discover the active sites of cobalt (Co) cations in different coordination structures, though Co-based oxides show their great potency in catalytic ozone elimination for air cleaning. Herein, different Co-based oxides are controllably synthesized including hexagonal wurtzite CoO-W with Co2+ in tetrahedral coordination (CoTd2+) and CoAl spinel with dominant CoTd2+, cubic rock salt CoO-R with Co2+ in octahedral coordination (CoOh2+), MgCo spinel with dominant Co3+ in octahedral coordination (CoOh3+), and Co3O4 with mixed CoTd2+ and CoOh3+. The valences are proved by X-ray photoelectron spectroscopy, and the coordinations are verified by X-ray absorption fine structure analysis. The ozone decomposition performances are CoOh3+ â¼ CoOh2+ â« CoTd2+, and CoOh3+ and CoOh2+ show a lower apparent activation energy of â¼42-44 kJ/mol than CoTd2+ (â¼55 kJ/mol). In specific, MgCo shows the highest decomposition efficiency of 95% toward 100 ppm ozone at a high space velocity of 1,200,000 mL/gh, which still retains at 80% after a long-term running of 36 h at room temperature. The high activity is explained by the d-orbital splitting in the octahedral coordination, favoring the electron transfer in ozone decomposition reactions, which is also verified by the simulation. These results show the promising prospect of the coordination tuning of Co-based oxides for highly active ozone decomposition catalysts.
ABSTRACT
Bisphenol compounds exist widely in the environment and pose potential hazards to the environment and human health, which has aroused widespread concern. Therefore, there is an urgent need for an efficient and sensitive analytical method to enrich and determine trace bisphenols in environmental samples. In this work, magnetic porous carbon (MPC) was synthesized by one-step pyrolysis combined with a solvothermal method for magnetic solid-phase extraction of bisphenols. The structural properties of MPC were characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and saturation magnetization analysis. Its adsorption properties were evaluated by adsorption kinetics and adsorption isotherm studies. By optimizing the magnetic solid-phase extraction and capillary electrophoresis separation conditions, a capillary electrophoresis separation and detection method for four bisphenols was successfully constructed. The results showed that the detection limits of the proposed method for the four bisphenols were 0.71-1.65 ng/mL, the intra-day and inter-day precisions were 2.27-4.03% and 2.93-4.42%, respectively, and the recoveries were 87.68%-108.0%. In addition, the MPC could be easily recycled and utilized, and even if the magnetic solid-phase extraction was repeated 5 times, the extraction efficiency could still be kept above 75%.
Subject(s)
Carbon , Solid Phase Extraction , Humans , Porosity , Adsorption , Solid Phase Extraction/methods , Magnetic Phenomena , Electrophoresis, Capillary/methods , Limit of DetectionABSTRACT
Molecular dynamic simulations of aqueous mixtures of imidazolium ionic liquids (ILs) were performed to elucidate the dependence of the ionic diffusivity on the microscopic structures changed by water. Two distinct regimes of the average ionic diffusivity (Dave) were identified with the increased water concentrations: the jam regime with slowly increased Dave and the exponential regime with rapidly increased Dave, which are found to be directly correlated to the ionic association. Further analysis leads to two general relationships independent of IL species between Dave and the degree of ionic association: (i) a consistent linear relationship between Dave and the inverse of ion-pair lifetimes (1/τIP) in the two regimes and (ii) an exponential relationship between normalized diffusivities (DÌave) and short-ranged interactions between cations and anions (Eions), with different interdependent strengths in the two regimes. These findings revealed and quantified the direct correlation between dynamic properties and ionic association in IL-water mixtures.
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Acrylate photoresists have gained considerable attention in recent years owing to their high resolution, high sensitivity, and versality. In this work, a series of thermally stable copolymers are synthesized by introducing an isobornyl group, and well characterized using Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectra (1H-NMR). The effects of polymerization conditions on the molecular weight and their further influence on lithography are explored. By analyzing the thermal properties, film-forming capabilities, and the patterning behavior of these copolymers, a direct correlation between lithography performance and polymerization conditions is established via the molecular weight. In addition, the baking temperature of lithography is also optimized by atomic force microscopy (AFM), after which a line resolution of 0.1 µm is observed under the exposure of a 248 nm UV light and electron beam. Notably, our synthesized photoresist displays dual-tone resist characteristics when different developers are applied, and the reaction mechanism of acid-catalyzed hydrolysis is finally proposed by comparing the structural changes before and after exposure.
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Chronic liver injury leads to progressive liver fibrosis and ultimately cirrhosis, a major cause of morbidity and mortality worldwide. However, there are currently no effective anti-fibrotic therapies available, especially for late-stage patients, which is partly attributed to the major knowledge gap regarding liver cell heterogeneity and cell-specific responses in different fibrosis stages. To reveal the multicellular networks regulating mammalian liver fibrosis from mild to severe phenotypes, we generated a single-nucleus transcriptomic atlas encompassing 49â¯919 nuclei corresponding to all main liver cell types at different stages of murine carbon tetrachloride (CCl 4)-induced progressive liver fibrosis. Integrative analysis distinguished the sequential responses to injury of hepatocytes, hepatic stellate cells and endothelial cells. Moreover, we reconstructed cell-cell interactions and gene regulatory networks implicated in these processes. These integrative analyses uncovered previously overlooked aspects of hepatocyte proliferation exhaustion and disrupted pericentral metabolic functions, dysfunction for clearance by apoptosis of activated hepatic stellate cells, accumulation of pro-fibrotic signals, and the switch from an anti-angiogenic to a pro-angiogenic program during CCl 4-induced progressive liver fibrosis. Our dataset thus constitutes a useful resource for understanding the molecular basis of progressive liver fibrosis using a relevant animal model.
Subject(s)
Endothelial Cells , Liver Cirrhosis , Mice , Animals , Endothelial Cells/metabolism , Liver Cirrhosis/chemically induced , Liver Cirrhosis/genetics , Liver Cirrhosis/metabolism , Liver Cirrhosis/veterinary , Carbon Tetrachloride/toxicity , Cell Communication , MammalsABSTRACT
The isolation of circulating tumor cells (CTCs) from whole blood is a challenging task. Although various studies on the separation of CTCs by acoustofluidic devices have been reported, difficulties still persist, such as the complicated equipment, high cost, and difficult operation. Those problems should be resolved urgently. Herein, we developed an acoustofluidic chip separation system coupled with an ultrasonic concentrated energy transducer (UCET) system for efficient separation of CTCs. In the separation system, the acoustically sensitive particles were pre-focused by inertial forces of the PDMS chip channel structure. Then, the particles with different sizes were separated by acoustic radiation forces (ARF). In this study, the circulating tumor cells was simulated (CTCs-like particles) by aminated mesoporous acoustically sensitive particles (MSN@AM) encapsulated carboxylate polystyrene microspheres (PS-COOH). Subsequently, efficient CTCs-like particles separation was achieved by the acoustofluidic chip coupling system. This study effectively separated polystyrene microspheres carrying acoustically sensitive particles (MSN@AM@PS-COOH). However, the MSNs agglomerates and PS microspheres without acoustically sensitive particles did not show phenomenon of separation. This method allows to efficiently separate 2 µm MSNs agglomeratesï¼8.0-8.9 µm PS microspheres and 10-10.5 µm MSN@AM@PS-COOH particles. It is demonstrated that the CTCs-like particles show more sensitive response, longer moving distance, and more obvious separation effect at the condition of the low frequency traveling wave sound field (20 kHz from UCET). This system can maintain the same separation with reduced amount of reagents used for cancer detection. It may provide a reliable basis for sorting out CTCs efficiently from the whole blood of cancer patients.
Subject(s)
Microfluidic Analytical Techniques , Neoplastic Cells, Circulating , Humans , Ultrasonics , Neoplastic Cells, Circulating/pathology , Polystyrenes , Transducers , Cell Separation , Cell Line, Tumor , Microfluidic Analytical Techniques/methodsABSTRACT
For a long time, the detection of nitroimidazole antibiotics (NIABs) has been a research focus in environmental analytical chemistry. In this work, a novel technique for the analysis of nitroimidazoles was established based on capillary electrophoresis (CE). UiO-66, synthesized using a solvothermal method, was utilized as an adsorbent in the dispersive solid-phase extraction (DSPE) of five different NIABs. The separation and detection of NIABs in environmental water samples were accomplished using the CE diode array detection method. The optimal extraction conditions were obtained after systematically studying the effects of adsorption time, the amount of extractant, and elution solvent on extraction efficiency. According to the results of the study, the limit of detections of the five NIABs were between 16 and 97 ng/mL, the relative standard deviations were between 0.32% and 0.55%, and the spike recoveries were between 87.43% and 104.8%. This study presents a novel technique for measuring NIABs in complex water samples.
Subject(s)
Nitroimidazoles , Water Pollutants, Chemical , Anti-Bacterial Agents/analysis , Nitroimidazoles/analysis , Water Pollutants, Chemical/analysis , Electrophoresis, Capillary/methods , Solid Phase Extraction/methods , Water , Chromatography, High Pressure LiquidABSTRACT
Among head and neck cancers, oral squamous cell carcinoma (OSCC) is the most common malignant tumor. N-7-methylguanosine (m7G) and lncRNAs are both related to the development and progression of tumors. Therefore, this study aims to explore and establish the prognostic signal of OSCC based on m7G-related lncRNAs. In this study, RNA sequencing transcriptome data of OSCC patients were downloaded from The Cancer Genome Atlas (TCGA) database. Therefore, m7G-related lncRNAs were identified as differentially expressed in OSCC. Then, univariate Cox regression analysis and LASSO regression analysis were conducted to evaluate the prognostic significance of differentially expressed lncRNAs. Consequently, the abovementioned lncRNAs were assigned five OSCC patient risk scores, with high-risk and low-risk patients assigned to each group. Different signaling pathways were significantly enriched between the two groups as determined by set enrichment analysis (GSEA). Multivariate Cox regression analysis confirmed the factors used to construct the nomogram model. Then, the prognosis of the nomogram model was evaluated. Consequently, high-risk individuals had higher immune infiltration levels. According to the results of a study that evaluated the sensitivity of different risk subgroups to antitumour drugs, the high-risk group had a high sensitivity to doxorubicin. By performing real-time polymerase chain reaction (RTâPCR), we verified the expression of these five m7G lncRNAs. Therefore, the model based on five m7G-related lncRNAs was able to predict the overall survival rates of OSCC patients and guide their treatment. It can also spur new ideas about how to prevent and treat OSCC.
ABSTRACT
The misuse of organic pollutants such as nitrofuran antibiotics (NFAs) and 2,6-dichloro-4-nitroaniline (DCN) has become a hot topic of global concern, and developing rapid, efficient, and accurate techniques for detecting NFAs and pesticides in water is a major challenge. Here, we designed a novel lead-based anion 2D metal-organic framework (MOF){[(CH3)2NH2]2[Pb(TCBPE)(H2O)2]}n (F3) with interlocking structures, in which TCBPE stands for 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene. Powder X-ray diffraction and thermogravimetric analysis revealed that F3 has excellent chemical and solvent stability. It is worth noting that F3 has a grinding discoloration effect. The solvent-protected grinding approach achieved F3B with a high quantum yield (QY = 73.77%) and blue fluorescence, while the direct grinding method produced F3Y with a high quantum yield (QY = 37.27%) and yellow-green fluorescence. Importantly, F3B can detect NFAs in water rapidly and sensitively while remaining unaffected by other antibiotics. F3Y can identify DCN in water quickly and selectively while remaining unchanged by other pesticides. F3B demonstrated high selectivity and rapid response to NFAs at a limit of detection (LOD) as low as 0.26 µM, while F3Y indicated high selectivity and responded quickly to DCN in water at an LOD as low as 0.14 µM. The method was successfully applied to detect NFAs in actual water samples of the fish tanks and ponds as well as the pesticide DCN in soil samples. The recovery rates were 97.0-105.15% and 102.2-106.48%, and the relative standard deviations were 0.63-1.45% and 0.29-1.69%, respectively. In addition, F3B and F3Y can be made into fluorescent test papers for the visual detection of NFAs and DCN, respectively. Combined with experiments and density functional theory calculations, the mechanism of fluorescence quenching of MOFs by target analytes was also revealed.
Subject(s)
Nitrofurans , Pesticides , Animals , Anti-Bacterial Agents/analysis , Pesticides/analysis , Water/chemistry , SolventsABSTRACT
The development of efficient electrochemical seawater splitting catalysts for large-scale hydrogen production is of great importance. In this work, we report an amorphous Co-Mo-B film on Ni foam (Co-Mo-B/NF) via a facile one-step electrodeposition process. Such amorphous Co-Mo-B/NF possesses superior activity with a small overpotential of 199 mV at 100 mA cm-2 for a hydrogen evolution reaction in alkaline seawater. Notably, Co-Mo-B/NF also maintains excellent stability for at least 24 h under alkaline seawater electrolysis.