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1.
J Hazard Mater ; 422: 126855, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34425434

RESUMO

Microplastics (MPs) occur in the source water of worldwide drinking water treatment plants (DWTPs). Pre-oxidation treatments become the initial stage for MPs treatment in DWTPs. Investigating the modifications of MPs after pre-oxidations is important to understand their fate in DWTPs. In this study, potassium permanganate oxidation (PPO) was applied to treat four high abundant MPs in DWTPs, including polyethylene (PE), polyethylene terephthalate (PET), polyvinylchloride (PVC) and polystyrene (PS). Influences of polymer types, sizes and pH were considered. After 10 mg L-1 PPO, only slight corrosions were observed on all MPs. Whereas, the appearances of O-Mn spectrum and the observation of nano-scale particles indicated the generation of nascent state Mn-oxides (MnO2) on MPs surface. This adhesion of MnO2 contributed to increasing density and hydrophilicity. As a result, the sinking performance of MPs was enhanced, e.g. the sinking ratio of 6.5 µm MPs increased 30% (PET), 20% (PVC) and 30% (PS) compared with pristine ones upon pH 7 PPO. These results implied that the practical PPO can enhance the sinking behavior of MPs. Of note, PE seems to be persistent and requires special concern.

2.
Food Sci Nutr ; 9(11): 6006-6019, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34760233

RESUMO

In order to improve the high cost of equipment and difficult management caused by the natural aging of Chinese rice wine (Huangjiu), micro-oxygen (MO) and electric field (PEF) technology are used to accelerate the aging of Huangjiu. The results showed that micro-oxygen and electric field have a significant effect on the sensory characteristics and flavor characteristics of Huangjiu. Compared with the naturally aged Huangjiu, the flavor compounds of Huangjiu treated with micro-oxygen and electric field increase significantly. Based on principal component analysis, Huangjiu processed at 0.35 mg L/day or 0.5 mg L/day combined electric field exhibited similar flavor to the natural aged Huangjiu, which was highly associated with long-chain fatty acid ethyl esters (C13-C18). Moreover, partial least squares regression demonstrated that sensory attributes of cereal aroma and astringency were highlighted after aging time, while fruit aroma, continuation, and full body were dominant after micro-oxygen and electric field treatment. Micro-oxygen and electric field effectively enhanced the quality of Huangjiu, which could be applied in other alcoholic beverages.

3.
Med Phys ; 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34786714

RESUMO

PURPOSE: Involuntary patient movement results in data discontinuities during computed tomography (CT) scans which lead to a serious degradation in the image quality. In this paper, we specifically address artifacts induced by patient motion during a head scan. METHOD: Instead of trying to solve an inverse problem, we developed a motion simulation algorithm to synthesize images with motion induced artifacts. The artifacts induced by rotation, translation, oscillation and any possible combination are considered. Taking advantage of the powerful learning ability of neural network, we designed a novel 3D network structure with both a large reception field and a high image resolution to map the artifact free images from artifact contaminated images. Quantitative results of the proposed method were evaluated against the results of U-Net and proposed networks without dilation structure. 30 sets of motion contaminated images from two hospitals were selected to do clinical evaluation. RESULT: Facilitating the training dataset with artifacts induced by variable motion patterns and the neural network, the artifact can be removed with good performance. Validation dataset with simulated random motion pattern showed outperformed image correction, and quantitative results showed the proposed network had the lowest normalized root mean-square-error, highest peak signal-to-noise ratio and structure similarity, indicating our network gave the best approximation of gold standard. Clinical image processing results further confirmed the effectiveness of our method. CONCLUSION: We proposed a novel deep learning based algorithm to eliminate motion artifacts. The CNNs trained with synthesized image pairs achieved promising result in artifacts reduction. The corrected images increased the diagnostic confidence compared with artifacts contaminated images. We believe that the correction method can restore the ability to successfully diagnose and avoid repeated CT scans in certain clinical circumstances. This article is protected by copyright. All rights reserved.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34275082

RESUMO

The development of water-stable metal-organic frameworks is a critical issue for their photocatalysis applications in water treatment. A phenyl-ethyl side chain with low surface energy was grafted into NH2-MIL-101(Fe) through a post-synthetic modification (PSM) method. As a result, a novel MIL-101(Fe)-1-(4-(ethyl)phenyl)urea (named MIL-101(Fe)-EPU) was synthesized. Basic morphology, crystal structure, and chemical bond features of MIL-101(Fe)-EPU were retained after PSM. Nitrogen X-ray photoelectron spectroscopy analysis confirmed the successful introduction of the phenyl-ethyl side chain, and this transformation increased its hydrophobicity and water stability. Contact angles of MIL-101(Fe)-EPU to water raised from 59.6 to 140.4°. And its structure maintained intact after 72 h water exposure, indicating higher stability than parent NH2-MIL-101(Fe). In the photocatalysis reaction with visible light and oxidant donor (H2O2), MIL-101(Fe)-EPU demonstrated a degradation efficiency of tetrabromobisphenol A with a reaction rate at 0.0313 min-1. The predominant reaction mechanism was OH·oxidation. The acid condition was beneficial for this photocatalysis reaction and high stability was observed. Besides, photocatalysis efficiency, crystal structure, and chemical structures were all retained in different actual water mediums, suggesting high adaptability of MIL-101(Fe)-EPU. In general, hydrophobic group grafting using a PSM method endows MIL-101(Fe)-EPU the potentiality as photocatalyst for organic contaminant elimination from water.

5.
Food Sci Nutr ; 9(7): 3885-3892, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34262745

RESUMO

Huangjiu (Chinese rice wine) is brewed in an open environment, where bacteria play an important role during the fermentation process. In this study, bacterial community structure and composition changes in the fermented mash liquid of mechanized Huangjiu, well-fermented manual Huangjiu (wines of good qualities), and poorly fermented manual Huangjiu (wines of poor qualities: spoilage, high acidity, low alcohol content) in different fermentation stages from Guyuelongshan Shaoxing Huangjiu company were analyzed via metagenomic sequencing. And bacterial metabolic difference was analyzed via gene prediction of metabolic pathway enzymes. The results showed that the bacterial diversity degree was abundant, and the number of bacterial species in every sample was approximately 200-400. Lactic acid bacteria (LAB) dominated the bacterial community of Huangjiu fermentation, and lactobacillus was predominant species in well-fermented Huangjiu while Lactobacillus brevis had an absolute dominance in spoilage Huangjiu. Further, gene prediction revealed that transformation of malate to pyruvate and lactate anabolism was more active in mash liquid of well-fermented manual Huangjiu, while acetate accumulation was stronger in mash liquid of poorly fermented manual Huangjiu, which explained acidity excess reason in poorly fermented Huangjiu at gene level.

6.
Adv Mater ; 33(29): e2007318, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34085735

RESUMO

Conductive polymers (CPs) integrate the inherent characteristics of conventional polymers and the unique electrical properties of metals. They have aroused tremendous interest over the last decade owing to their high conductivity, robust and flexible properties, facile fabrication, and cost-effectiveness. Compared to bulk CPs, porous CPs with well-defined nano- or microstructures possess open porous architectures, high specific surface areas, more exposed reactive sites, and remarkably enhanced activities. These attractive features have led to their applications in sensors, energy storage and conversion devices, biomedical devices, and so on. In this review article, the different strategies for synthesizing porous CPs, including template-free and template-based methods, are summarized, and the importance of tuning the morphology and pore structure of porous CPs to optimize their functional performance is highlighted. Moreover, their representative applications (energy storage devices, sensors, biomedical devices, etc.) are also discussed. The review is concluded by discussing the current challenges and future development trend in this field.

7.
Food Chem ; 352: 129368, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33667921

RESUMO

A high-performance voltammetric methodology was developed to achieve ultra-sensitive detection of riboflavin, employing an electrode modified by graphene oxide-covered hollow MnO2 spheres nanocomposite with high catalytic activity, large surface area, and hierarchical layered structure. Under the optimal conditions, the current responses of the oxidation peak located at -0.39 V showed a good linear relationship versus the concentration of riboflavin in the range of 1.0 nM-4.0 µM in acetate buffer (pH 5.4). The limit of detection was determined as 0.26 nM. Moreover, the proposed electrode exhibited high reproducibility (relative standard deviation of 1.7%, n = 10) and excellent stability (97.6% sensitivity within two months), which has been successfully applied to the quantification of riboflavin in complicated food matrices, with results in good accordance with those obtained by chromatography as a reference method, indicating it is an effective sensing platform for ultra-sensitive determination of riboflavin in practical applications.


Assuntos
Eletroquímica/instrumentação , Grafite/química , Compostos de Manganês/química , Óxidos/química , Riboflavina/análise , Catálise , Eletrodos , Análise de Alimentos , Limite de Detecção , Oxirredução , Reprodutibilidade dos Testes
8.
Nanotechnology ; 32(16): 165601, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33455954

RESUMO

A rationally designed strategy is developed to synthesize hierarchically porous Fe-based metal-organic frameworks (P-Fe-MOF) via solution-based self-assembly of diblock copolymers. The well-chosen amphiphilic diblock copolymers (BCP) of polystyrene-block-poly(acrylic acid) (PS-b-PAA) exhibits outstanding tolerance capability of rigorous conditions (e.g. strong acidity or basicity, high temperature and pressure), steering the peripheral crystallization of Fe-based MOF by anchoring ferric ions with outer PAA block. Importantly, the introduction of BCP endows MOF materials with additional mesopores (∼40 nm) penetrating whole crystals, along with their inherent micropores and introduced macropores. The unique hierarchically porous architecture contributes to fast charge transport and electrolyte ion diffusion, and thus promotes their redox reaction kinetics processes. Accordingly, the resultant P-Fe-MOF material as a new electrode material for supercapacitors delivers the unprecedented highest specific capacitance up to 78.3 mAh g-1 at a current density of 1 A g-1, which is 9.8 times than that of Fe-based MOF/carbon nanotubes composite electrode reported previously. This study may inspire new design of porous metal coordination polymers and advanced electrode materials for energy storage and conversion field.

9.
Water Res ; 186: 116360, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32896740

RESUMO

Wastewater treatment plants (WWTPs) are considerable microplastics (MPs) contributors to environmental waters. Knowledge about the MPs degradation process under ultraviolet irradiation was crucial to understanding the fate of MPs during and after water disinfection. In this study, surface alternations of polystyrene (PS), polyethylene (PE), polyvinylchloride (PVC) and polyethylene terephthalate (PET) under 254 nm (UV-C) and 185/254 nm (vacuum ultraviolet, VUV) irradiation were estimated. One-way treatment of MPs by UV or VUV with the recommended dose for WWTPs (USEPA, ~180 mJ cm-2) had little effect. In contrast, excessive exposure under twenty-times doses irradiation (3600 mJ cm-2) resulted in significant alternations on surface morphology, chemical feature and hydrophobicity. Noticeably morphology alterations, including cracks, wrinkles and protuberances, were observed for PS, PVC and PET, while PE was relatively resistant. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that UV irradiation induced cleavage of chemical bonds. Besides, simultaneous radical oxidation was predominant during VUV treatment, which contributed to the increasing generation of oxygen bonds, such as CO and CO, on all MPs surfaces. Drastic decreases of contact angle (> 20°) were observed for PS, PVC and PET even after 180 mJ cm-2 UV irradiation, indicating the UV disinfection in WWTPs can easily change their surface hydrophobicity. All these alternations weakened the adsorption capacity of non-polar benzene and polar ciprofloxacin on MPs. Generally, regular dose UV and VUV irradiation in water treatment disinfection can only induce slight effects on MPs surface characteristics and adsorption performance, while extreme dose irradiation can induce a potential reducing risk of organic contaminants migration along with MPs.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Microplásticos , Plásticos , Raios Ultravioleta , Vácuo
10.
Food Sci Nutr ; 8(8): 4027-4036, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32884684

RESUMO

As one of the three most famous brewed wines in the world, Chinese rice wine is made from rice and husked millet, containing 14 percent to 20 percent alcohol. Highly original, yellow wine brewing techniques are regarded as the model of the wine brewing industry in Asia. Shaoxing Huangjiu is produced in Zhejiang province and remains the oldest and most representative Chinese rice wine. During storage, Shaoxing Huangjiu is susceptible to environmental disturbance and produces colloidal haze to result in turbidity. In this study, the main composition and source of colloidal haze protein in Shaoxing Huangjiu were analyzed by two-dimensional electrophoresis and matrix-assisted laser ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS). The results showed that the proteins in colloidal haze mainly consisted of oat protein b1, oat-like protein, di-amylase inhibitor, pathogenesis-related protein, pathogenesis-related protein-4, chitinase II derived from wheat and oat-like protein, and beta-amylase derived from rice. The amino acid composition and secondary structure of haze protein and supernatant protein in Huangjiu were further explored by high-performance liquid chromatography and Fourier transform infrared spectroscopy. The study has broadened knowledge of the main composition and source of colloidal haze protein in Shaoxing Huangjiu. The corresponding results indicated that the amino acid composition from colloidal haze had the main characteristics of high hydrophobicity and low water solubility.

11.
Small ; 16(37): e2002701, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32776467

RESUMO

Nanomeshes with highly regular, permeable pores in plane, combining the exceptional porous architectures with intrinsic properties of 2D materials, have attracted increasing attention in recent years. Herein, a series of 2D ultrathin metal-organic nanomeshes with ordered mesopores is obtained by a self-assembly method, including metal phosphate and metal phosphonate. The resultant mesoporous ferric phytate nanomeshes feature unique 2D ultrathin monolayer morphologies (≈9 nm thickness), hexagonally ordered, permeable mesopores of ≈16 nm, as well as improved surface area and pore volume. Notably, the obtained ferric phytate nanomeshes can directly in situ convert into mesoporous sulfur-doped metal phosphonate nanomeshes by serving as an unprecedented reactive self-template. Furthermore, as advanced anode materials for Li-ion batteries, they deliver excellent capacity, good rate capability, and cycling performance, greatly exceeding the similar metal phosphate-based materials reported previously, resulting from their unique 2D ultrathin mesoporous structure. Therefore, the work will pave an avenue for constructing the other 2D ordered mesoporous materials, and thus offer new opportunities for them in diverse areas.

12.
Chemistry ; 26(46): 10433-10438, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32428368

RESUMO

The precise regulation of nucleation growth and assembly of polymers is still an intriguing goal but an enormous challenge. In this study, we proposed a pre-polymerization strategy to regulate the assembly and growth of polymers by facilely controlling the concentration of polymerization initiator, and thus obtained two kinds of different nanosheet-based porphyrin polymer materials using tetrakis-5,10,15,20-(4-aminophenyl) porphyrin (TAPP) as the precursor. Notably, due to the π-π stacking and doping of TAPP during the preparation process, the obtained PTAPP-nanocube material exhibits a high intrinsic bulk conductivity reaching 1.49×10-4  S m-1 . Profiting from the large π-conjugated structure of porphyrin units, closely stacked layer structure and excellent conductivity, the resultant porphyrin polymers, as electrode materials for lithium ion batteries, deliver high specific capacity (≈650 mAh g-1 at the current density of 100 mA g-1 ), excellent rate performance and long-cycle stability, which are among the best reports of porphyrin polymer-based electrode materials for lithium-ion batteries, to the best of our knowledge. Therefore, such a pre-polymerization approach would provide a new insight for the controllable synthesis of polymers towards custom-made architecture and function.

13.
ACS Omega ; 5(8): 4075-4082, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32149235

RESUMO

Graphene sheets have a vast number of potential applications due to their excellent properties. However, poor quality and harsh preparation conditions restrict their application. Here, few-layer graphene (FLG) sheet powder with high quality has been synthesized from waste expanded polystyrene (EPS) at low temperature by dense Fe cluster catalysis. The micron-sized FLG sheets comprising about three layers show high crystallinity and good electrical conductivity that are comparable to those of the shear-exfoliated graphene nanoplatelets. More than 70% carbon yield of FLG sheets from cheap EPS and their safe, controllable synthesis conditions make it easy to expand production. The catalytic formation mechanism of FLG sheets is studied.

14.
Chem Commun (Camb) ; 56(21): 3191-3194, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32068213

RESUMO

We developed ultrathin dual-mesoporous polymer nanosheets by combining co-assembly of different templates with in situ synthesis of functional polymers, which featured inherent smaller and template-directed larger mesopores (2.6 nm and 15 nm, respectively), ultrathin nanolayers (20 nm), high surface area (268 m2 g-1), intrinsic fluorescent properties and effective detectability for organophosphates.


Assuntos
Nanoestruturas/química , Organofosfatos/análise , Polímeros/química , Fluorescência , Estrutura Molecular , Tamanho da Partícula , Processos Fotoquímicos , Polímeros/síntese química , Porosidade , Propriedades de Superfície
15.
J Hazard Mater ; 384: 121483, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648891

RESUMO

The rational design of novel adsorption materials is imperative to remove toxic metal species from the polluted water. Herein, a core@shell structural Fe-Fe2O3@poly (hexachlorocyclotriphosphazene-co-polyethylenimine) (Fe-Fe2O3@PHCP) magnetic nanochain with high saturation magnetization was fabricated and used for effective adsorption and reduction of hexavalent chromium. The morphology and microstructure of Fe-Fe2O3@PHCP were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The effects of concentration, pH, contact time, temperature and coexisting ions on Cr (VI) removal were studied. Four kinetic models (pseudo-first-order, pseudo-second-order, Bangham and intraparticle diffusion models) and two isotherm models (Freundlich and Langmuir) were used to fit experimental data. Results show the adsorption capacity of Fe-Fe2O3@PHCP for Cr (VI) is up to 229.0 mg g-1. The excellent performance was ascribed to the favorable reduction of Cr (VI) to Cr (III), followed by the chelation of Cr (III) with imino groups. Meanwhile, the residual Cr (VI) were adsorbed on protonated amino and imino groups. The adsorption process is exothermic and spontaneous and nicely follows pseudo-second-order kinetics, intraparticle diffusion model and Langmuir isotherm model. These results indicated that easily separable Fe-Fe2O3@PHCP magnetic nanochains could be a promising adsorbent to remediate chromate wastewater.

16.
Nanomicro Lett ; 12(1): 31, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34138238

RESUMO

Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex materials. However, the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as microstructure. Here, we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy, using phytic acid-based natural compounds as an example, for the spatially controlled fabrication of metal coordination bio-derived polymers. The resultant ferric phytate polymer nanospheres feature hollow architecture, ordered meso-channels of ~ 12 nm, high surface area of 401 m2 g-1, and large pore volume of 0.53 cm3 g-1. As an advanced anode material, this bio-derivative polymer delivers a remarkable reversible capacity of 540 mAh g-1 at 50 mA g-1, good rate capability, and cycling stability for sodium-ion batteries. This study holds great potential of the design of new complex bio-materials with supramolecular chemistry.

17.
J Colloid Interface Sci ; 556: 278-291, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31454620

RESUMO

The development of novel adsorbents with high adsorption capacity and easy recovery property is imperative in the field of wastewater treatment. In this study, a hard template-induced assembly strategy was developed to fabricate the magnetic hollow poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol)-Fe3O4 (PZS-Fe3O4) hybrid nanocapsules, in which Fe3O4 nanoparticles were well embedded in the cross-linked PZS shell. The resulting samples were well characterized using SEM, TEM, EDS, FT-IR, VSM, XPS, XRD and N2 sorption. Then, using Safranine T (ST) as model dye, the adsorption behavior of as-prepared hollow PZS-Fe3O4 nanocapsules including adsorption kinetics, adsorption isotherms, adsorption mechanism, and recyclability were systematically evaluated and discussed. The results revealed that the magnetic hollow PZS-Fe3O4 nanocapsules own high adsorption capacity towards ST dye and outstanding magnetic separation functionality. The pseudo-second-order kinetic model and the Langmuir model can well describe the experimental data, and the adsorption process is controlled by more than one diffusion step. The interaction between ST dye and hollow PZS-Fe3O4 nanocapsules is ascribed to π-π interaction and electrostatic interaction. The thermodynamic parameters demonstrated that the adsorption processes were physical, endothermic, and spontaneous. Additionally, the magnetic hollow PZS-Fe3O4 nanocapsules also shows excellent peroxidase-like catalytic activity in the oxidation of 3,3',5,5'-tetramethylbenzidine with H2O2, indirectly confirming the adsorption kinetic results.

18.
ACS Appl Mater Interfaces ; 11(31): 27798-27804, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31305977

RESUMO

Interface engineering of two-dimensional (2D) transition-metal composites for activating plane and edge sites is a significant yet step challenging in boosting their performance for hydrogen evolution reaction (HER). Herein, two-dimensional (2D) MoO3 with petal-shaped nanosheets confining Pd nanoparticles (Pd@MoO3 heterostructure) was prepared via an efficient solvothermal and subsequently hydrogen reduction processes. The atomically dispersed Pd-substituted sites in the interface of Pd nanoparticles and 2D MoO3 lattices significantly play an important role in enhancing the electrocatalytic and photocatalytic performances of the Pd@MoO3 heterostructure. As a result, the Pd@MoO3 heterostructure exhibits a high HER catalytic activity with an overpotential (η) of 71 mV to achieve a current density of 10 mA cm-2 and an extremely low Tafel slope of 42.8 mV dec-1 in 0.5 M H2SO4 solution. Furthermore, the photoresponse of the Pd@MoO3 heterostructure is about 3 times higher than that of the MoO3 nanosheets. This work highlighted a strategy of interface engineering for highly efficient cost-effective catalyst for hydrogen evolution by electric and solar energy conversion.

19.
Nanoscale ; 11(18): 8785-8797, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31032826

RESUMO

The development of novel large-scale synthesis protocols for heteroatom-doped porous carbon nanosheets is highly imperative for wastewater purification and high-performance electrode materials. In the present work, we propose a simple and feasible explosion-assisted activation strategy to fabricate a kind of N-doped porous carbon nanosheet (N-PCNS) at a large scale, in which only lactose and zinc nitrate were used as raw materials. The obtained N-PCNS possesses hierarchical micro- and mesopore nanostructures with a high specific surface area of 879 m2 g-1 while keeping a high nitrogen content of 3.73 at%. The adsorption properties of the N-PCNS were systematically evaluated through adsorption of neutral red (NR) dye. The adsorption capacity of the N-PCNS was as high as 439.6 mg g-1, meanwhile the adsorption process exhibited fine correlation with the Langmuir isotherm and pseudo-second-order kinetic models. As an electrode material for supercapacitors, the specific capacitance of the N-PCNS is up to 263 F g-1 at 1 A g-1 and 194 F g-1 at 20 A g-1, revealing superior rate performance. The capacitance retention after 10 000 cycles at 20 A g-1 is 96%, demonstrating excellent cycling stability. Our work provides an effective approach to achieve the large-scale preparation of high-performance doped carbon materials.

20.
J Econ Entomol ; 112(3): 1120-1129, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-30770933

RESUMO

Alligatorweed, Alternanthera philoxeroide (Mart.) Griseb. (Amaranthaceae) is an invasive weed in China that is often kept under control by the alligatorweed flea beetle, Agasicles hygrophila Selman and Vogt (Coleoptera: Chrysomelidae) introduced into China from Argentina in the 1980s. Elevated CO2 levels have been shown to have a direct effect on Ag. hygrophila. In order to fully evaluate the indirect effects of three different atmospheric concentrations of CO2 (420, 550, and 750 ppm) on the population parameters of Ag. hygrophila reared on Al. philoxeroides, we collected life table data for Ag. hygrophila using the age-stage, two-sex life table method. In general, there were no significant differences in the lengths of the preadult parameters among the three treatments. The adult duration and total longevity of males, however, did increase as CO2 increased in concentration. Although the adult preoviposition and total preoviposition periods decreased, the fecundity, oviposition days, eggs per oviposition day, net reproductive rate, intrinsic rate of increase, and finite rate of increase all increased significantly at the high CO2 concentration. Consequently, we determined that the Ag. hygrophila population size will potentially increase rapidly over a short period of time at elevated CO2 concentrations. Our results suggest that 550 and 750 ppm CO2 may also cause physiological changes in Al. philoxeroides that, in turn, provide enhanced nutrition for increasing reproduction in Ag. hygrophila by accelerating maturation of their reproductive system. These results indicate that the efficacy of Ag. hygrophila as a biological control agent against Al. philoxeroides will likely be increased at 550 and 750 ppm CO2.


Assuntos
Acanthaceae , Amaranthaceae , Besouros , Animais , Argentina , Dióxido de Carbono , China , Feminino , Masculino
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