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1.
J Vis Exp ; (205)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38526077

RESUMEN

Rodent damage poses a significant threat to crops, human life, and health. Compared to chemical rodent control, such as placing poisonous baits, it is more economical and environmentally friendly to use physical methods, such as building a rodent-proof wall. This study introduces a method of physically controlling harmful rodents and four methods of calculating the effect of rodents control. To understand the controlling effect of the rodent-proof wall, an investigation was conducted on the Dongting Lake beach and corresponding farmland in the embankment in April and July 2012. Our findings illustrated that the density of the reed vole Microtus fortis in the farmland with rodent-proof walls was 0.52%, significantly lower than that in the farmland without rodent-proof walls (1.76%) after artificial trapping and drug extermination (χ2 = 3.900, P = 0.048). The density of M. fortis that had migrated into the farmland in dikes with a rodent-proof wall decreased by 98.53%, significantly higher than the decrease of density in dikes without a rodent-proof wall (86.61%) (χ2 = 11.060, P = 0.01). The results demonstrated the effectiveness of rodent-proof wall control. Therefore, building a rodent-proof wall should be advocated and vigorously promoted to prevent the migration of rodents into the Dongting Lake area and similar environments, as they cause harm.


Asunto(s)
Arvicolinae , Roedores , Animales , Humanos , Lagos , Productos Agrícolas
2.
J Hazard Mater ; 469: 133968, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38452682

RESUMEN

Pb2+ is a heavy metal ion pollutant that poses a serious threat to human health and ecosystems. The conventional methods for detecting Pb2+ have several limitations. In this study, we introduce a novel fluorescent probe that enables the detection of Pb2+ in the near-infrared region, free from interference from other common ions. A unique characteristic of this probe is its ability to rapidly and accurately identify Pb2+ through ratiometric measurements accompanied by a large Stokes shift of 201 nm. The limit of detection achieved by probe was remarkably low, surpassing the standards set by the World Health Organization, and outperforming previously reported probes. To the best of our knowledge, this is the first organic small-molecule fluorescent probe with both near-infrared emission and ratiometric properties for the detection of Pb2+. We present a triple-mode sensing platform constructed using a probe that allows for the sensitive and selective recognition of Pb2+ in common food items. Furthermore, we successfully conducted high-quality fluorescence imaging of Pb2+ in various samples from common edible plants, HeLa cells, Caenorhabditis elegans, and mice. Importantly, the probe-Pb2+ complex exhibited tumour-targeting capabilities. Overall, this study presents a novel approach for the development of fluorescent probes for Pb2+ detection.


Asunto(s)
Colorantes Fluorescentes , Plomo , Humanos , Animales , Ratones , Células HeLa , Ecosistema
3.
Molecules ; 28(20)2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37894667

RESUMEN

In this research, we successfully produced hierarchical porous activated carbon from biowaste employing one-step KOH activation and applied as ultrahigh-performance supercapacitor electrode materials. The coconut shell-derived activated carbon (CSAC) features a hierarchical porous structure in a honeycomb-like morphology, leading to a high specific surface area (2228 m2 g-1) as well as a significant pore volume (1.07 cm3 g-1). The initial test with the CSAC electrode, conducted in a 6 M KOH loaded symmetric supercapacitor, demonstrated an ultrahigh capacitance of 367 F g-1 at a current density of 0.2 A g-1 together with 92.09% retention after 10,000 cycles at 10 A g-1. More impressively, the zinc-ion hybrid supercapacitor using CSAC as a cathode achieves a high-rate capability (153 mAh g-1 at 0.2 A g-1 and 75 mAh g-1 at 10 A g-1), high energy density (134.9 Wh kg-1 at 175 W kg-1), as well as exceptional cycling stability (93.81% capacity retention after 10,000 cycles at 10 A g-1). Such work thus illuminates a new pathway for converting biowaste-derived carbons into materials for ultrahigh-performance energy storge applications.

4.
Anal Methods ; 15(21): 2685-2692, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37226487

RESUMEN

Raw halloysite was purified by using sodium hexametaphosphate and utilized as the solid-phase extraction sorbent for the determination of biguanides from dietary supplements. The purified halloysite was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The purified halloysite interacted with biguanides through hydrophilic interaction and ion exchange on account of its abundant hydroxyl groups and negative charge. Compared with traditional extraction methods based on hydrophobic interaction and/or ion exchange, the purified halloysite adsorbed more biguanides due to hydrophilicity and ion exchange, with a sample loading volume of up to 100 mL at least. Excellent reproducibility of halloysite purification was achieved, with within-batch (n = 3) and batch-to-batch (n = 3) relative standard deviations in the ranges of 1.5-4.2% and 5.6-8.8%, respectively. Coupled with reversed-phase liquid chromatography-tandem mass spectrometry, a low limit of detection of 0.3 µg kg-1 was obtained. The intra- and inter-day mean recoveries of the biguanides spiked at three levels in dietary supplements were within the ranges of 88.5-107.2% and 86.4-102.0%, respectively. The intra- and inter-day precisions were within the ranges of 1.5-6.4% and 5.4-9.9%, respectively. These results indicated that the developed method is efficient for the determination of trace biguanides in dietary supplements.


Asunto(s)
Biguanidas , Extracción en Fase Sólida , Arcilla , Reproducibilidad de los Resultados , Límite de Detección , Extracción en Fase Sólida/métodos , Suplementos Dietéticos
5.
ChemSusChem ; 15(22): e202201575, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36149300

RESUMEN

The surface grafting of electro-negative cyano groups on polymer carbon nitrides (PCNs) is an effective way to tail their electronic structure. Despite the significant progress in the synthesis of cyano group-enriched PCN, developing a simple and efficient method remains challenging. Here, a facile strategy was developed for fabricating surface cyano-rich PCN (PCN-DM) with a porous structure via chemical vapor modification using diaminomaleonitrile. The cyano groups of diaminomaleonitrile substituted the amino groups on PCN surface via a deamination. The hydrogen production rate of the PCN-DM was approximately 17 times higher than that of pristine PCN. This significant increase in photocatalytic performance could be assigned to the fusion of cyano groups in the surface of PCN, forming new gap states that broadened the visible-light harvesting and accelerated charge separation for photoredox reactions. This study unveils a promising approach for incorporating functional units in the design of novel photocatalysts for efficient hydrogen production.


Asunto(s)
Polímeros , Gases , Hidrógeno/química , Polímeros/química
6.
Anal Chem ; 94(32): 11298-11306, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35926081

RESUMEN

Herein, a novel strategy was proposed for identifying carbon monoxide (CO), which plays a crucial part in living systems. For the first time, we have managed to design, synthesize, and characterize successfully this new Cu2+-assisted fluorescent probe (DPHP) in detecting CO. Compared with the commonly adopted Pd0-mediated Tsuji-Trost reaction recognition method, such a new strategy did not engage costly palladium (II) salt and generated no leaving group, indicating a satisfactory anti-interference ability. The recognition mechanism was confirmed by IR, 1H NMR titration, HR-MS, cyclic voltammetry, X-ray photoelectron spectroscopy, electron paramagnetic resonance, and optical properties. Surprisingly, it was found that the new method achieved high selectivity and rapid identification of CO with a lower limit of detection (1.7 × 10-8 M). More intriguingly, it could recognize endogenous and exogenous CO in HeLa cells. The cytotoxicity of this new method was so low that it allowed the detection of CO in mice and zebrafish. Basically, our results trigger a novel viewpoint of rationally designing and synthesizing advanced materials for CO detection with unique features, impelling new research in detection chemistry.


Asunto(s)
Monóxido de Carbono , Colorantes Fluorescentes , Animales , Colorantes Fluorescentes/química , Colorantes Fluorescentes/toxicidad , Células HeLa , Humanos , Ratones , Imagen Óptica/métodos , Pez Cebra
7.
Chem Sci ; 13(11): 3129-3139, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35414886

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) with boron-nitrogen (BN) moieties have attracted tremendous interest due to their intriguing electronic and optoelectronic properties. However, most of the BN-fused π-systems reported to date are difficult to modify and exhibit traditional aggregation-caused quenching (ACQ) characteristics. This phenomenon greatly limits their scope of application. Thus, continuing efforts to seek novel, structurally distinct and functionally diverse structures are highly desirable. Herein, we proposed a one-stone-two-birds strategy including simultaneous exploration of reactivity and tuning of the optical and electronic properties for BN-containing π-skeletons through flexible regioselective functionalization engineering. In this way, three novel functionalized BN luminogens (DPA-BN-BFT, MeO-DPA-BN-BFT and DMA-DPA-BN-BFT) with similar structures were obtained. Intriguingly, DPA-BN-BFT, MeO-DPA-BN-BFT and DMA-DPA-BN-BFT exhibit completely different emission behaviors. Fluorogens DPA-BN-BFT and MeO-DPA-BN-BFT exhibit a typical ACQ effect; in sharp contrast, DMA-DPA-BN-BFT possesses a prominent aggregation induced emission (AIE) effect. To the best of our knowledge, this is the first report to integrate ACQ and AIE properties into one BN aromatic backbone with subtle modified structures. Comprehensive analysis of the crystal structure and theoretical calculations reveal that relatively large twisting angles, multiple intermolecular interactions and tight crystal packing modes endow DMA-DPA-BN-BFT with strong AIE behavior. More importantly, cell imaging demonstrated that luminescent materials DPA-BN-BFT and DMA-DPA-BN-BFT can highly selectively and sensitively detect lipid droplets (LDs) in living MCF-7 cells. Overall, this work provides a new viewpoint of the rational design and synthesis of advanced BN-polycyclic aromatics with AIE features and triggers the discovery of new functions and properties of azaborine chemistry.

8.
Chem Soc Rev ; 51(6): 2031-2080, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35226024

RESUMEN

Sensing analysis is significantly important for human health and environmental safety, and has gained increasing concern. As a promising material, porous organic polymers (POPs) have drawn widespread attention due to the availability of plentiful building blocks and their tunable structures, porosity and functions. Moreover, the permanent porous nature could provide a micro-environment to interact with guest molecules, rendering POPs attractive for application in the sensing field. In this review, we give a comprehensive overview of POPs as a platform for sensing applications. POP-based sensors are mainly divided into five categories, including fluorescence turn-on sensors, fluorescence turn-off sensors, ratiometric fluorescent sensors, colorimetric sensors and chemiresistive sensors, and their various sensing applications in detecting explosives, metal ions, anions, small molecules, biological molecules, pH changes, enantiomers, latent fingerprints and thermosensation are summarized. The different structure-based POPs and their corresponding synthetic strategies as well as the related sensing mechanisms mainly including energy transfer, donor-acceptor electron transfer, absorption competition quenching and inner filter effect are also involved in the discussion. Finally, the future outlook and perspective are addressed briefly.


Asunto(s)
Metales , Polímeros , Colorimetría , Humanos , Iones , Porosidad
9.
Angew Chem Int Ed Engl ; 58(30): 10132-10137, 2019 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-31087592

RESUMEN

A series of novel BN tetraphene derivatives have been prepared successfully for the first time via a post-functionalization strategy. The optical and electronic properties of these derivatives could be tuned systematically by the incorporation of different substituents on the main skeleton. The functionalized BN-containing luminogens have been explored for the detection of latent fingerprints (LFPs) on different substrates, including glass, aluminum foil, plastic, and ironware. This strategy provides great versatility in LFP imaging and good potential in elucidating the chemical information within LFPs, making the strategy valuable in forensic investigations.


Asunto(s)
Compuestos de Boro/química , Dermatoglifia , Humanos , Luminiscencia , Mediciones Luminiscentes , Modelos Moleculares , Estructura Molecular , Propiedades de Superficie
10.
Chem Commun (Camb) ; 52(22): 4227-30, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26912372

RESUMEN

A series of intensely blue fluorescent BN-embedded tetraphene derivatives have been synthesized by the catalytic cyclization of BN-naphthalenes with alkynes. The BN-tetraphene can be selectively functionalized to give a substituted derivative via bromination followed by a cross-coupling reaction. The electronic and photophysical properties of the novel BN-tetraphene system were investigated using UV-vis and fluorescence spectroscopy, electrochemical cyclic voltammetry, and DFT calculations, which disclosed its distinct electronic and photophysical properties from the analogous hydrocarbon system.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/química , Catálisis , Electroquímica , Procesos Fotoquímicos , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
11.
Org Lett ; 15(2): 282-5, 2013 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-23273017

RESUMEN

A new Pd-catalyzed reaction of thiophenes with alkynes via C-H and C-S bond activation has been developed. This provides a new approach to prepare sulfur-containing compounds. An interesting salt effect was observed, and the reaction's efficiency and selectivity depend not only on the type but also on the amount of the salt used.

12.
Org Lett ; 13(19): 5252-5, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-21888338

RESUMEN

Herein, a Pd-catalyzed reaction of simple and diverse bromothiophenes with alkynes via regioselective C-S bond activation is reported. This provides a new approach to prepare sulfur-based heterocycles and fulvenes.

13.
Org Biomol Chem ; 9(14): 5036-8, 2011 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-21647501

RESUMEN

A simple and efficient palladium-catalyzed three-component domino reaction of bromothiophenes with internal alkynes has been developed to produce benzo[b]thiophenes in moderate to good yields.


Asunto(s)
Compuestos Organometálicos/química , Paladio/química , Tiofenos/síntesis química , Catálisis , Estructura Molecular , Estereoisomerismo , Tiofenos/química
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