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1.
Int J Biol Macromol ; 267(Pt 2): 131653, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38631568

RESUMEN

Aerogel possesses the advantages of high specific surface area, low density, and high porosity, which have shown great application in thermal regulation due to its efficient light scattering capability. However, traditional polymer-based aerogels have poor mechanical properties and lack ductility in outdoor applications, the cooling efficiency of the material is easily affected by damage during transportation, installation, and environmental factors. In this work, combining the porous nature of aerogels and the high ductility of membranes, a polylactic acid-based porous membrane cooler was developed by combining a regular honeycomb surface porous structure design and physical/chemical modification to enhance flexibility, using a simple non-solvent induced phase separation method. This porous membrane exhibits both super-flexibility (116 % elongation at break) and porous characteristics. It achieves a sub-ambient temperature decrease of 4-6 °C under direct sunlight. The optimized porous membrane demonstrates high solar reflectance (94 % of peak reflectivity, 90 % of average reflectivity) and strong infrared emissivity (96 % of peak emissivity, 91 % of average emissivity), it also maintains a solar peak reflectivity of 91 % under 100 % tensile strain and 1000 bending cycles, the cooler still maintains a cooling effect of 2-5 °C below ambient temperature. This work paves the way for developing mechanical flexible and strong radiative coolers for thermal regulation.


Asunto(s)
Membranas Artificiales , Poliésteres , Poliésteres/química , Porosidad , Polimerizacion , Temperatura , Resistencia a la Tracción
2.
ACS Nano ; 17(20): 20153-20166, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37801407

RESUMEN

Flexible tactile sensors show great potential for portable healthcare and environmental monitoring applications. However, challenges persist in scaling up the manufacturing of stable tactile sensors with real-time feedback. This work demonstrates a robust approach to fabricating templated laser-induced graphene (TLIG)-based tactile sensors via laser scribing, elastomer hot-pressing transfer, and 3D printing of the Ag electrode. With different mesh sandpapers as templates, TLIG sensors with adjustable sensing properties were achieved. The tactile sensor obtains excellent sensitivity (52260.2 kPa-1 at a range of 0-7 kPa), a broad detection range (up to 1000 kPa), a low limit of detection (65 Pa), a rapid response (response/recovery time of 12/46 ms), and excellent working stability (10000 cycles). Benefiting from TLIG's high performance and waterproofness, TLIG sensors can be used as health monitors and even in underwater scenarios. TLIG sensors can also be integrated into arrays acting as receptors of the soft robotic gripper. Furthermore, a deep neural network based on the convolutional neural network was employed for texture recognition via a soft TLIG tactile sensing array, achieving an overall classification rate of 94.51% on objects with varying surface roughness, thus offering high accuracy in real-time practical scenarios.


Asunto(s)
Grafito , Robótica , Dispositivos Electrónicos Vestibles , Tacto , Redes Neurales de la Computación
3.
Environ Sci Pollut Res Int ; 30(39): 91199-91206, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37474856

RESUMEN

Dimethachlon, a dicarboximide fungicide, has gained widespread usage in Asian countries. While considered a low-toxicity fungicide, concerns regarding potential health effects, such as nephrotoxicity, have emerged. To date, neither China nor other countries have established maximum residue limit (MRL) for dimethachlon on grapes, and exposure risk assessment of dimethachlon is lacking. Here, we developed a QuEChERS method coupled with gas chromatography-mass spectrometry (GC-MS) to investigate the dissipation rates and terminal residues of dimethachlon in grapes, along with an assessment of dietary risk to consumers. Our results indicated that the average recoveries of dimethachlon in grapes ranged from 74 to 76%. The limit of quantification (LOQ) was 0.050 mg/kg. After undergoing 112 days of storage at -18 °C, the dissipation rate of dimethachlon in grapes was found to be less than 30%, suggesting a state of stable storage. In the context of good agricultural practice (GAP) guidelines, the half-lives of dimethachlon in grapes were 14.3-18.1 days, which is notably longer compared to the reported values for other crops. The terminal residues of dimethachlon in grapes at 14 and 21 days were found to be < 0.05-0.53 mg/kg and < 0.05-0.29 mg/kg, respectively. Regarding the dietary risk assessment, the calculated risk quotient (RQ) value was significantly below 100%, indicating a negligible chronic risk of dimethachlon in grapes at the recommended dosage. This study provides an important reference for the analysis of dimethachlon and offers valuable empirical data to support the establishment of MRL.


Asunto(s)
Fungicidas Industriales , Residuos de Plaguicidas , Vitis , Fungicidas Industriales/análisis , Residuos de Plaguicidas/análisis , Vitis/química , Contaminación de Alimentos/análisis , Semivida , Medición de Riesgo , China
4.
Food Chem ; 421: 136149, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37086520

RESUMEN

Bifenazate is widely recognized as an effective acaricide for citrus production in various regions. Detecting both the parent compound of bifenazate and its metabolite, bifenazate-diazene, simultaneously can be challenging owing to their tendency to undergo chemical interconversion. Current methods developed for detecting bifenazate or bifenazate-diazene residues often involve lengthy incubation periods and may not effectively separate the two compounds. In this study, we developed a convenient and fast method based on a modified QuEChERS method assisted by oxidants to concurrently detect bifenazate and bifenazate-diazene. Based on preliminary analysis, it appears that ferric chloride has the ability to react with a reducing substance present in citrus, which may prevent the reduction of bifenazate-diazene. The method was validated and applied in a field trial. This work reports a novel strategy to establish a balanced 'neutral' condition to create a potential method for efficient determination of bifenazate acaricide residues in fruit matrices.


Asunto(s)
Acaricidas , Citrus , Residuos de Plaguicidas , Acaricidas/análisis , Frutas/química , Residuos de Plaguicidas/análisis
5.
RSC Adv ; 13(13): 8765-8778, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36936844

RESUMEN

Tricyclazole, propiconazole, imidacloprid, and thiamethoxam are commonly used pesticides in paddy fields. It is necessary and practical to remove pesticides from the water environment because the low utilization rate of pesticides will produce residues in the water environment. It is known that there are few studies on the preparation of biochar adsorption pesticides by the walnut shell and few studies on the removal of tricyclazole and propiconazole. Based on this, this paper used the walnut shell as raw material and boric acid as an activator to prepare biochar by the one-step method. The boric acid modified walnut shell biochar (WAB4) with a specific surface area of 640.6 m2 g-1, exhibited the high adsorption capacity of all four pesticides (>70%) at pH 3-9. The adsorption capacities of tricyclazole, propiconazole, imidacloprid, and thiamethoxam were 171.67, 112.27, 156.40, and 137.46 mg g-1, respectively. The adsorption kinetics fitted the pseudo-second-order kinetic model and the adsorption isotherm curves conformed to the Freundlich isotherm model. The adsorption of pesticides by WAB4 was associated with hydrogen bonding, pore filling, hydrophobic effects, and π-π interactions. More significantly, WAB4 has excellent adsorption capacity compared to other adsorbents for real water samples. Finally, walnut shell biochar has no significant acute toxicity to Daphnia magna. This work shows that walnut shell-based biochar has a good effect on the removal of pesticides at a wide range of pH and is economical and safe, providing a new idea for the removal of pesticides in water.

6.
Int J Biol Macromol ; 237: 124186, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36990401

RESUMEN

Biochar materials have been widely employed for adsorption of pollutants, which necessitates further consideration of their efficiency and safety in environmental remediation. In this study, a porous biochar (AC) was prepared through the combination of hydrothermal carbonization and in situ boron doping activation to effectively adsorb neonicotinoids. The adsorption process was shown to be a spontaneous endothermic physical adsorption process, where the predominant interaction forces between the acetamiprid and AC were electrostatic and hydrophobic interactions. The maximum adsorption capacity was 227.8 mg g-1for acetamiprid and the safety of AC was verified by simulating the situation where the aquatic organism (D. magna) was exposed to the combined system (AC & neonicotinoids). Interestingly, AC was observed to reduce the acute toxicity of neonicotinoids owing to the reduced bioavailability of acetamiprid in D. magna and the newly generated expression of cytochrome p450. Thus, it enhanced the metabolism and detoxification response in D. magna, which reducing the biological toxicity of acetamiprid. This study not only demonstrates the potential application of AC from a safety perspective, but also provides insight into the combined toxicity caused by biochar after adsorption of pollutants at the genomic level, which fills the gap in related research.


Asunto(s)
Boro , Contaminantes Químicos del Agua , Adsorción , Celulosa , Carbón Orgánico/química , Neonicotinoides/química , Contaminantes Químicos del Agua/química , Cinética
7.
Food Chem ; 412: 135546, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-36716625

RESUMEN

The abuse of organophosphorus pesticides (OPPs) in tea planting makes it easy to transfer from tea into its infusion, bringing potential health risks to consumers. Thus, it is essential to adopt reliable techniques to remove OPPs from tea infusion. In this study, three treatment methods were used to modify carbonized bacterial cellulose (CBC) to improve its adsorption performance. Among them, CBC treated by hydrazine hydrate (N-CBC) had the best adsorption effect, whose removal rate for dicrotophos is 13 times that of CBC. The in-depth study of adsorption mechanism proved that hydrophobic interaction dominated the adsorption of OPPs onto N-CBC. The pseudo-second-order kinetic model and Langmuir isotherm model were more suitable to describe the process. Additionally, there were no significant changes in tea infusion quality after N-CBC treatment. This work clarifies that N-CBC benefitted from simple preparation method, excellent adsorption performance and unique adsorption mechanism has potential applications in tea infusion.


Asunto(s)
Plaguicidas , Contaminantes Químicos del Agua , Compuestos Organofosforados/análisis , Té/química , Adsorción , Celulosa , Cinética , Contaminantes Químicos del Agua/química
8.
Adv Sci (Weinh) ; 9(34): e2204036, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36257833

RESUMEN

The hydrogen-bonded organic frameworks (HOFs) have rarely been considered for photocatalytic application, given their weak stability and low activity. One presumably effective strategy to improve the photocatalytic performance of the HOFs is to produce a core-shell composite by fabricating a particular nanostructure using stable HOFs. To this end, the surface-functionalized metal-organic frameworks (MOFs) are used as the host matrix to support the in situ assembly and subsequent multisite growth of the stable HOFs. MOF@HOF eventually obtains core-shell hybrids, i.e., NH2 -UiO-66@DAT-HOF. This newly synthesized core-shell nanostructure exhibits excellent stability and superb photocatalytic performance. For example, in terms of tetracycline degradation, the optimal composite presents an apparent reaction rate constant of 60.7 and 7.6 times higher than its parent materials NH2 -UiO-66 and DAT-HOF. Such a pronounced enhancement in photocatalytic efficiency of the hybrid material is attributed to the broader visible-light utilization range compared to its individual parent material as well as the efficient separation of charge carriers supported by the S-scheme heterojunction. In addition, it is particularly notable that the photocatalytic efficiency of the yielded core-shell nanostructure can remain high after several-cycle applications. This work provides a universal scheme for synthesizing the MOF@HOF core-shell hybrids.


Asunto(s)
Estructuras Metalorgánicas , Metales , Enlace de Hidrógeno , Hidrógeno
9.
Food Chem ; 396: 133640, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35839723

RESUMEN

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPDQ) can pose a threat to human health through the food chain because of their ubiquitous presence in the environment and the biotoxicity on organisms. In this work, we developed modified QuEChERS methods coupled with high performance liquid chromatography tandem mass spectrometry (HPLC/MS-MS) to explore whether 6PPD and 6PPDQ are present in fish and honey. The proposed methods showed acceptable limits of quantification (0.00043-0.001 mg/kg), linearity (R2 > 0.99), recovery (73.3%-108.3%), matrix effect (70.4%-95.6%) and repeatability (RSD < 8.4%). Accordingly, 6PPD and 6PPDQ have been discovered in snakehead, weever and Spanish mackerel fish, while none of which have been detected in the honey samples. The results of our work contributed to increasing public attention to 6PPD and 6PPDQ in agricultural products and provided important reference for the analysis of them.


Asunto(s)
Contaminantes Ambientales , Miel , Animales , Cromatografía Líquida de Alta Presión/métodos , Contaminantes Ambientales/análisis , Peces , Miel/análisis , Humanos , Espectrometría de Masas
10.
Food Chem ; 395: 133565, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-35763926

RESUMEN

A high-quality antibody production strategy is significant for immunoassay. In this work, four general haptens were proposed based on the 3D structure and surface electrostatic potential of molecular modeling. It was found that the sensitivity and specificity of polyclonal antibodies (pAbs) mainly depended on the bond angle of shapes liked "V" between haptens and proteins and hydrophobic parts of haptens. The quantified process was employed to obtain pAbs against cyhalofop-butyl and its metabolites (CAFs), with the IC50 value of 4.9 µg·L-1 under optimal conditions. The limit of quantization (LOQ) of the ultrasensitive icELISA in brown rice was 2 µg·kg-1. The recoveries were 74%-110%, with a coefficient of variation (CV) less than 10%. This study indicated that the hapten property approach led to an improved immunoassay.


Asunto(s)
Formación de Anticuerpos , Haptenos , Anticuerpos , Especificidad de Anticuerpos , Ensayo de Inmunoadsorción Enzimática , Haptenos/química , Inmunoensayo , Modelos Moleculares
11.
Sci Total Environ ; 838(Pt 2): 156013, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35588826

RESUMEN

The typical tire manufacturing additive 6PPD, its metabolites 6PPDQ and 4-Hydroxy should be monitored because of their ubiquitous presence in the environment and the high toxicity of 6PPDQ to coho salmon. The toxic effect of 6PPD and its metabolites have been revealed superficially, especially on behavioral characteristics. However, the behavioral indicators explored so far are relatively simple and the toxic causes are poorly understood. With this in mind, our work investigated the toxic effects of 6PPD, 6PPDQ and 4-Hydroxy on adult zebrafish penetratingly through machine vision, and the meandering, body angle, top time and 3D trajectory are used for the first time to show the abnormal behaviors induced by 6PPD and its metabolites. Moreover, neurotransmitter changes in the zebrafish brain were measured to explore the causes of abnormal behavior. The results showed that high-dose treatment of 6PPD reduced the velocity by 42.4% and decreased the time at the top of the tank by 91.0%, suggesting significant activity inhibition and anxiety. In addition, γ-aminobutyric acid and acetylcholine were significantly impacted by 6PPD, while dopamine exhibited a slight variation, which can explain the bradykinesia, unbalance and anxiety of zebrafish and presented similar symptoms as Huntingdon's disease. Our study explored new abnormal behaviors of zebrafish induced by 6PPD and its metabolites in detail, and the toxic causes were revealed for the first time by studying the changes of neurotransmitters, thus providing an important reference for further studies of the biological toxicity of 6PPD and its metabolites.


Asunto(s)
Discinesias , Pez Cebra , Animales , Ansiedad/inducido químicamente , Conducta Animal , Neurotransmisores/metabolismo , Pez Cebra/fisiología
12.
ACS Appl Mater Interfaces ; 13(31): 37433-37444, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34324306

RESUMEN

Microstructures play a dominant role in flexible electronics to improve the performance of the devices, including sensitivity, durability, stretchability, and so on. However, the complicated and expensive fabrication process of these microstructures extremely hampers the large-scale application of high-performance devices. Herein, we propose a novel method to fabricate flexible graphene-based sensors with a 3D microstructure by generating laser-induced graphene (LIG) on the 3D printed polyether ether ketone corrugated substrate, which is referred to as CLIG. Based on that, two integrated piezoresistive sensors are developed to monitor the precise strain and pressure signals. Contributed to the 3D corrugated graphene structure, the sensitivities of strain and pressure sensors can be up to 2203.5 and 678.2 kPa-1, respectively. In particular, the CLIG-based strain sensor exhibits a high resolution to the microdeformation (small as 1 µm or 0.01% strain) and remarkable durability (15,000 cycles); meanwhile, the pressure sensor presents a remarkable working range (1-500 kPa) and fast response time (24 ms). Furthermore, the CLIG-based sensors provide a stable data source in the applications of human-motion monitoring, pressure array, and self-sensing soft robotic systems. High accuracy allows CLIG sensors to recognize more subtle signals, such as pulse, swallowing, gesture distinction of human, and movement status of soft robotics. Overall, this technology shows a promising strategy to fabricate high-performance sensors with high efficiency and low cost.

13.
Chemosphere ; 280: 130877, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34162102

RESUMEN

A mild and one-pot activation approach of activated carbon was found. The feasibility of boric acid as the activated reagent which was used for the adsorption of four tetracyclines antibiotics (TCs) in water. Boric acid activated carbon (BAC) from bioresource has a much higher removal efficiency than currently reported biochar. The maximum adsorption capacity of BAC is 173.9 mg/g for TCs. BAC is an ecofriendly, nontoxic, and low-cost absorbent from sawdust waste. BAC and TCs could keep coalescing at least 55 days on the surface without stable release. BAC was fully characterized by using scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Raman, zeta potential, and Brunauer-Emmett-Teller analysis; the large surface area and rich pore structure were proved. The interaction between BAC and TCs are hydrogen bond interaction, π-π interaction, and electrostatic interaction. These interactions are also related to the surface charge of BAC and the TCs' species of ions in different pH. Furthermore, the adsorption kinetics and adsorption isotherm of BAC were studied thoroughly. The pseudo-first-order, pseudo-second-order, intra-particle diffusion, Elovich Langmuir, Freundlich, and Dubinin-Radushkevich models were fitted and the physical adsorption process was proved. After the study on adsorption thermodynamics, adsorption exhibits a spontaneous and favorable process.


Asunto(s)
Lignina , Contaminantes Químicos del Agua , Adsorción , Antibacterianos , Biomasa , Ácidos Bóricos , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Tetraciclinas , Termodinámica , Agua
14.
RSC Adv ; 11(56): 35408-35414, 2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-35493164

RESUMEN

Organic pollutants widely exist in the environment, causing a lot of potential harm. On account of excellent physical and chemical properties, graphdiyne (GDY) has been widely used in many potential fields. However, it is crucial to develop more synthetic methods to achieve mass production of GDY and explore its universality in the removal of organic pollutants. Herein, six transition metal salts including Cu salts and Pd salts were selected as catalysts to successfully synthesize GDY with different morphologies by a coupling reaction. The method is simple, safe, easy to operate and suitable for large-scale production. Among them, CuSO4-catalyzed GDY has higher yield (>90%), lower density and fewer defects. Furthermore, it can efficiently remove organic pollutants from water such as dyes, tetracycline antibiotics and neonicotinoid pesticides, demonstrating that the adsorption material has a certain universality. In particular, the adsorption effect of GDY on dye is comparable to that of MWCNTs and stronger than that of conventional adsorbents such as graphene and activated carbon. This work provides more possibilities for the industrial production of GDY and its promising application for the removal of organic pollutants.

15.
Sci Total Environ ; 757: 143810, 2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33279197

RESUMEN

A non-metallic and low-cost novel phosphorus and boron co-doping graphite carbon nitride (PB-g-C3N4) photocatalyst was prepared by a facile thermal copolymerization of urea with B2O3 and (NH4)2·HPO4. The novel PB-g-C3N4 exhibited excellent optical and electrical properties and the photocatalytic elimination efficiency for atrazine (AT, can make feminization of male frogs in the wild, and even induce reproductive cancers in humans.) has been greatly improved compared with the pristine g-C3N4. The results of characterization techniques indicate that the introduced B and P atoms most probably to substitute for sp2-hybridized C atoms in triazine rings. O2- and h+ are the dominant active species to induce the elimination of AT demonstrated by the radical-trapping experiments. And a possible elimination pathway is proposed according to the detected main intermediates. In addition, PB-g-C3N4 was applied to the simultaneous photocatalytic elimination of 9 triazine herbicides, and the effects of different initial concentrations, pH, fulvic acid (FA) and ion species on their elimination effects were studied. And it was proved that the photocatalytic performance of PB-g-C3N4 did not significant decrease after 4 times of reuse.

16.
RSC Adv ; 10(73): 44688-44698, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-35516286

RESUMEN

Graphene/polyaniline composites have attracted considerable attention as high-performance supercapacitor electrode materials; however, there are still numerous challenges for their practical applications, such as the complex preparation process, high cost, and disequilibrium between energy density and power density. Herein, we report an efficient method to produce graphene/polyaniline composites via a one-pot ball-milling process, in which aniline molecules act as both the intercalator for the exfoliation of graphite and the monomer for mechanochemical polymerization into polyaniline clusters on the in situ exfoliated graphene sheets. The graphene/polyaniline composite electrode delivered a large specific capacitance of 886 F g-1 at 5 mV s-1 with a high retention of 73.4% at 100 mV s-1. The high capacitance and rate capability of the graphene/polyaniline composite can contribute to the fast electron/ion transfer and dominantly capacitive contribution because of the synergistic effects between the conductive graphene and pseudocapacitive polyaniline. In addition, a high energy density of 40.9 W h kg-1 was achieved by the graphene/polyaniline-based symmetric supercapacitor at a power density of 0.25 kW kg-1, and the supercapacitor also maintained 89.1% of the initial capacitance over 10 000 cycles.

17.
J Ethnopharmacol ; 248: 112317, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31629862

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Arnebiae Radix, a common herbal medicine in China, is often utilized to treat blood-heat syndrome and has been reported to exert an effect on the heart. AIM OF THE STUDY: The combination of acetylcholine (Ach) and CaCl2 has been widely used to induce atrial fibrillation (AF) in animals. However, whether Arnebiae Radix displays any preventive action on Ach-CaCl2 induced AF in rats remains uncertain. In our study, we attempted to investigate the protective effects of Arnebiae Radix on Ach-CaCl2 induced AF compared to amiodarone, which was employed as the positive control. MATERIALS AND METHODS: To establish the AF model, SD rats were treated with a mixture of 0.1 mL/100 g Ach-CaCl2 (60 µg/mL Ach and 10 mg/mL CaCl2) by tail vein injection for 7 days. Rats were also given a gavage of Arnebiae Radix (0.18 g/mL) one week before or concurrently with the establishment of the AF model. At the end of the experimental period, the induction, duration and timing of AF were monitored using electrocardiogram recordings. Left atrial tissues were stained to observe the level of fibrosis. Electrophysiological measurements were used to examine atrial size and function. RESULTS: In Ach-CaCl2-induced AF rats, Arnebiae Radix decreased AF induction, duration and susceptibility to AF. In addition, Arnebiae Radix significantly reduced atrial fibrosis and inhibited atrial enlargement induced by Ach-CaCl2. Moreover, there was an apparent improvement in cardiac function in the Arnebiae Radix-treated group. CONCLUSIONS: Our findings indicate that Arnebiae Radix treatment can attenuate Ach-CaCl2-induced atrial injury and serve as an effective therapeutic strategy for the treatment of AF in the future.


Asunto(s)
Antiarrítmicos/farmacología , Fibrilación Atrial/prevención & control , Función del Atrio Izquierdo/efectos de los fármacos , Remodelación Atrial/efectos de los fármacos , Boraginaceae , Frecuencia Cardíaca/efectos de los fármacos , Extractos Vegetales/farmacología , Acetilcolina , Animales , Antiarrítmicos/aislamiento & purificación , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/fisiopatología , Boraginaceae/química , Cloruro de Calcio , Modelos Animales de Enfermedad , Fibrosis , Masculino , Extractos Vegetales/aislamiento & purificación , Ratas Sprague-Dawley , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos
18.
Environ Pollut ; 255(Pt 1): 113150, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31541823

RESUMEN

Excessive pesticide residues in the environment have caused more and more serious social problems. In this article, the polymer materials and graphene oxide were smoothly grafted together through surface-initiated atom-transfer radical polymerization. A temperature and pH dual-sensitive adsorbent was successfully obtained, which was used for the removal of six sulfonylurea herbicides in the aquatic environment. Experiment results showed that the adsorbent could efficiently remove the tested pesticides in aqueous solution rapidly (only 1 min). The adsorption process was in consist with the pseudo-second-order kinetics equation and Freundlich model, and the thermodynamic parameters were also calculated. Furthermore, the mechanism for removal performance was judged as n-π, π-π, hydrogen bonding, hydrophobic and electrostatic interaction verdict. Exhilaratingly, the material showed no significant toxicity to Daphnia magna on risk assessment.


Asunto(s)
Grafito/química , Herbicidas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Animales , Daphnia/efectos de los fármacos , Herbicidas/química , Herbicidas/toxicidad , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Termodinámica , Contaminantes Químicos del Agua/química
19.
Sci Total Environ ; 647: 57-65, 2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-30077855

RESUMEN

In this study, nano zirconium carbide (n-ZrC) was synthesized by preceramic polymers method, and it was used to adsorb emodin and physcion from solutions for the first time. The prepared material was characterized by various technologies. The adsorption experiment was carried out to investigate the emodin and physcion removal performance. The results indicate that the pseudo-second-order kinetic model and the Langmuir model correlated satisfactorily to the experimental data, and the thermodynamic parameters are also calculated. Especially, n-ZrC can remove >95% of emodin or physcion in a minute under the optimal conditions, it is the fastest adsorption rate compared to other commonly used adsorbents (commercial zirconium carbide, activated carbon, C18, PSA, GCB and florisil). The adsorption mechanism was discussed, which suggests that Van der Waals' forces are the primary driving power during the adsorption process. Moreover, n-ZrC is stable at different pH and it can be reused at least fifteen times.

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