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1.
iScience ; 25(1): 103692, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35036876

RESUMO

Parasitoid wasps of the smallest flying insects with bristled wings exhibit sophisticated flight behaviors while challenging biomechanical limitations in miniaturization and low-speed flow regimes. Here, we investigate the morphology, material composition, and mechanical properties of the bristles of the parasitoid wasps Anagrus Haliday. The bristles are extremely stiff and exhibit a high-aspect-ratio conical tubular structure with a large Young's modulus. This leads to a marginal deflection and uniform structural stress distribution in the bristles while they experience high-frequency flapping-induced aerodynamic loading, indicating that the bristles are robust to fatigue. The flapping aerodynamics of the bristled wings reveal that the wing surfaces act as porous flat paddles to reduce the overall inertial load while utilizing a passive shear-based aerodynamic drag-enhancing mechanism to generate the requisite aerodynamic forces. The bristled wing may have evolved as a novel design that achieves multiple functions and provides innovative ideas for developing bioinspired engineering microdevices.

2.
Bioresour Technol ; 344(Pt A): 126148, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34673188

RESUMO

Two consortia of lignocellulolytic microbes (CL and YL) were isolated from the rumen of ruminants. Their ability to facilitate the degradation of rice straw and enhance methane (CH4) production were evaluated, both individually and combined with lactic acid bacteria (LAB). After 30 days of degradation, rice straw powders (RSPs) were observed to change in physical structure and also displayed a significant reduction in lignocellulose content. Combined application of microbial consortia with LAB efficiently improved enzymatic hydrolysis of RSPs, increasing organic acid as well as mono- and disaccharide contents. Synergistic action between microbial consortia and LAB enhanced CH4 yield, and rice straw treated with YL + LAB had the highest CH4 production (357.53 mL CH4/g VS), more than fivefold of the control. The newly identified microbial consortia are capable of efficiently degrading lignocellulosic biomass. Functioning synergistically with LAB, they provide a feasible way biodegrade rice straw and enhance methane production from agricultural wastes.


Assuntos
Lactobacillales , Oryza , Animais , Metano , Consórcios Microbianos , Rúmen
3.
Ecotoxicol Environ Saf ; 226: 112852, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34601268

RESUMO

New cerium-doped carbon quantum dots (CDs:Ce) were developed in this study using hydrothermal synthesis method. The small and uniform sizes and nearly spherical lattice of CDs:Ce indicate its high stability, satisfactory water solubility, and biocompatibility. Wheat was treated with Ce, CDs, and different concentrations (0.01, 0.025, 0.05, 0.1, 0.2, and 0.4 mg/mL) of CDs:Ce. The results showed that, compared with the control group, Ce, CDs, and CDs:Ce could promote the growth and development of wheat in a certain concentration range. Wheat demonstrated the optimal morphological index (compared with the control, the root number, root length, leaf length, and plant height were increased by 45%, 57%, 28%, and 46%, respectively), maximum chlorophyll content (increased by 51%) and peroxidase activity (increased by 76%), and minimum malondialdehyde content (reduced by 68%) after treatment of 0.025 mg/mL of CDs:Ce. Hence, wheat plants can adsorb and transport CDs:Ce from roots to stems and leaves through fibrovascular tissues. The majority of CDs:Ce are concentrated in roots while some accumulate in leaves. A considerable amount of CDs:Ce gather in cell walls, fibrovascular tissues, leaf veins, and stomata. CDs:Ce can be applied to agricultural production activities as a new agricultural nanofertilizer and technology of plant in vivo imaging.


Assuntos
Cério , Pontos Quânticos , Carbono , Cério/toxicidade , Crescimento e Desenvolvimento , Triticum
4.
Small ; 17(31): e2102027, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34197035

RESUMO

Developing highly active electrocatalysts toward oxygen evolution reaction (OER) is critical for the application of water splitting for hydrogen production and can further alleviate the energy crisis problem, but still remaining challenging. Especially, unlocking the catalytic site, in turn, helps design the available catalysts. Herein, the nanorod cobalt telluride with sulfur incorporation grown on a carbon cloth (S-CoTe/CC) as catalysts for OER, which displays extraordinary catalytic activity, is reported. Significantly, the in situ formed CoOOH species on the surface of S-CoTe merited from the structure evolution during the OER process serves as the active species. Furthermore, density functional theory calculations demonstrate that sulfur incorporation can tailor the electronic structure of active species and substantially optimize the free energy, accelerating the OER kinetics. This work provides an in-depth understanding of enhanced OER mechanism through foreign elements incorporating into precatalysts and is beneficial for the guiding design of more efficient catalysts.

5.
ACS Appl Mater Interfaces ; 11(43): 40069-40077, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31580051

RESUMO

Lithium-selenium (Li-Se) batteries have recently attracted more and more attentions as new secondary battery systems due to the similarity but better performances than lithium-sulfur (Li-S) batteries. However, the dissolution of selenium in electrolytes results in low selenium utilization, concentration polarization, inferior capacities, and unstable cycling performances. Herein, 46.58 wt% of selenium is loaded on carbon cloths through the calcination process, which were directly used as self-supporting cathodes. Carbonized polyacrylonitrile (PAN) nanofiber membranes produced by electrospinning are worn as the protective clothing between the cathode and separator to avoid the loss and dissolution of selenium. The stabilization of Li-Se batteries was enhanced by introducing two interlayers, as expected, they exhibit a stable reversible average capacity of 590 mA h g-1 during 1000 cycles at a current density of 0.5 C (1 C = 675 mA g-1). No polyselenide formation is found during charging/discharging, and the effects of the introduced PAN interlayers on improving the stability and reducing the polarization of the assembled Li-Se batteries are confirmed by mechanistic characterizations. These regulated Li-Se batteries present great application potential in the future, and the design idea can also be promoted to explore other energy storage systems.

6.
Angew Chem Int Ed Engl ; 58(39): 13717-13721, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31286608

RESUMO

Organic p-type semiconductors with tunable structures offer great opportunities for hybrid perovskite solar cells (PVSCs). We report herein two dithieno[3,2-b:2',3'-d]pyrrole (DTP) cored molecular semiconductors prepared through π-conjugation extension and an N-alkylation strategy. The as-prepared conjugated molecules exhibit a highest occupied molecular orbital (HOMO) level of -4.82 eV and a hole mobility up to 2.16×10-4  cm2 V-1 s-1 . Together with excellent film-forming and over 99 % photoluminescence quenching efficiency on perovskite, the DTP based semiconductors work efficiently as hole-transporting materials (HTMs) for n-i-p structured PVSCs. Their dopant-free MA0.7 FA0.3 PbI2.85 Br0.15 devices exhibit a power conversion efficiency over 20 %, representing one of the highest values for un-doped molecular HTMs based PVSCs. This work demonstrates the great potential of using a DTP core in designing efficient semiconductors for dopant-free PVSCs.

7.
Acta Pharm ; 68(2): 159-170, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29702482

RESUMO

The purpose of this study was to prepare a mosapride citrate-resin (Amberlite® IRP 88) complex and orally fast-disintegrating tablets of the resin complex. The resinate complex of mosapride-Amberlite® IRP 88, mass ratio 2:1, was prepared in an ethanol-water solution. The effects of alcohol concentration, temperature, and pH of the solution on complex formation were evaluated. The complex physicochemical properties were characterized by differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. Orally disintegrating tablets were prepared by direct compression and were optimized using the response surface method. Optimized orally fast-disintegrating tablets disintegrated within 18 s. The pH dependence of mosapride release from the tablet decreased drug dissolution in simulated saliva, whereas it promptly released in the pH 1.0 solution. The data reported herein clearly demonstrate that tablets containing the mosapride-Amberlite® IRP 88 complex for oral disintegration could be particularly useful for patients with swallowing difficulties.


Assuntos
Benzamidas/administração & dosagem , Etanol/química , Fármacos Gastrointestinais/administração & dosagem , Morfolinas/administração & dosagem , Resinas Sintéticas/química , Administração Oral , Benzamidas/química , Varredura Diferencial de Calorimetria , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Fármacos Gastrointestinais/química , Humanos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Morfolinas/química , Saliva/metabolismo , Solubilidade , Comprimidos , Difração de Raios X
8.
Nanoscale Res Lett ; 5(9): 1468-1473, 2010 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-20730123

RESUMO

An inorganic-organic hybrid fluorescence chemosensor (DA/SBA-15) was prepared by covalent immobilization of a dansylamide derivative into the channels of mesoporous silica material SBA-15 via (3-aminopropyl)triethoxysilane (APTES) groups. The primary hexagonally ordered mesoporous structure of SBA-15 was preserved after the grafting procedure. Fluorescence characterization shows that the obtained inorganic-organic hybrid composite is highly selective and sensitive to Hg(2+) detection, suggesting the possibility for real-time qualitative or quantitative detection of Hg(2+) and the convenience for potential application in toxicology and environmental science.

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