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1.
Chem Sci ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39309080

RESUMO

Organic-inorganic metal halide (OIMH) glass offers the advantages of large-scale production, high transparency, and minimal light scattering. However, undesired crystallization in OIMH glass can occur, leading to deteriorated transparency. Herein, a series of bisphosphonium organic cations were designed to construct Mn-based metal halide crystals with a photoluminescence quantum yield (PLQY) near unity, alongside the development of highly thermally stable OIMH glasses. Two strategies were employed to lower the melting point of OIMH: alkyl chain elongation and fluorine substitution. The (Hex-3,4-2F)MnBr4·MeOH (Hex-3,4-2F = hexane-1,6-diylbis((3,4-difluorobenzyl)diphenylphosphonium)) crystal delivers a glass transition temperature of 100 °C and the highest T g/T m ratio (0.82) among OIMHs. The resulting OIMH glass exhibits a PLQY of 47.6%, achieves an impressive resolution of 25 lp mm-1 in X-ray imaging, and remains transparent even after being heated at 90 °C for six weeks. These bisphosphonium-based OIMH glasses present a feasible design for the practical application of OIMH glasses in radiation detection.

2.
Water Res ; 267: 122417, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39299138

RESUMO

The higher efficiency of electro-fermentation in synthesizing medium-chain fatty acids (MCFAs) compared to traditional fermentation has been acknowledged. However, the functional mechanisms of electrode-biofilm enhancing MCFAs synthesis remain research gaps. To address this, this study proposed a continuous flow electrode-biofilm reactor for chain elongation (CE). After 225 days of operation, stable electrode-biofilms formed and notably improved caproate yield by more than 38 %. The electrode-biofilm was enriched with more CE microorganisms and electroactive bacteria compared to the suspended sludge microorganisms, including Caproicibacterium, Oscillibacter and Pseudoramibacter. Besides, the upregulated CE pathways were evaluated by metagenomic analysis, and the results indicated that the pathways such as acetyl-CoA and malonyl-[acp] formation, reverse beta-oxidation, and fatty acid biosynthesis pathway were all markedly enhanced in cathodic biofilm, more than anodic biofilm and suspended microorganisms. Moreover, microbial community regulated processes like bacterial chemotaxis, flagellar assembly and quorum sensing, crucial for electrode-biofilm formation. Electron transfer, energy metabolism, and microbial interactions were found to be prominently upregulated in the cathodic biofilm, surpassing levels observed in anodic biofilm and suspended sludge microorganisms, which further enhanced CE efficiency. In addition, the statistical analyses further highlighted key microbial functions and interactions within the cathodic biofilm. Oscillospiraceae_bacterium was identified to be the most active microbe, alongside pivotal roles played by Caproiciproducens_sp._NJN-50, Clostridiales_bacterium, Prevotella_sp. and Pseudoclavibacter_caeni. Eventually, the proposed microbial collaboration mechanisms of cathodic biofilm were ascertained. Overall, this study uncovered the biological effects of the electrode-biofilm on MCFAs electrosynthesis, thereby advancing biochemicals production and filling the knowledge gaps in CE electroactive biofilm reactors.

3.
Angew Chem Int Ed Engl ; : e202410514, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38966937

RESUMO

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X-ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I-) serve as the electron donor. The prepared butyl(2-[2-(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4-I) exhibits bright blue emission and an ultra-high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n-π and anion-π stacking in solid-state C4-I. Photophysical studies of C4-I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near-pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X-ray attenuation ability endowed by I, C4-I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s-1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X-ray attenuation ability, and excellent scintillator performance.

4.
Bioresour Technol ; 406: 130959, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876286

RESUMO

Despite the increased research efforts aimed at understanding iron-based conductive materials (CMs) for facilitating chain elongation (CE) to produce medium chain fatty acids (MCFAs), the impact of these materials on microbial community functions and the adaptation mechanisms to their biotoxicity remain unclear. This study found that the supply of zero-valent iron (ZVI) and magnetite enhanced the MCFAs carbon-flow distribution by 26 % and 52 %, respectively. Metagenomic analysis revealed the upregulation of fatty acid metabolism, pyruvate metabolism and ABC transporters with ZVI and magnetite. The predominant functional microorganisms were Massilibacterium and Tidjanibacter with ZVI, and were Petrimonas and Candidatus_Microthrix with magnetite. Furthermore, it was demonstrated that CE microorganisms respond and adapt to the biotoxicity of iron-based CMs by adjusting Two-component system and Quorum sensing for the first time. In summary, this study provided a new deep-insight on the feedback mechanisms of CE microorganisms on iron-based CMs.


Assuntos
Ferro , Ferro/farmacologia , Ferro/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Ácidos Graxos/metabolismo , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Óxido Ferroso-Férrico/química , Percepção de Quorum/efeitos dos fármacos
5.
Angew Chem Int Ed Engl ; 62(7): e202216504, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36504433

RESUMO

Glass is a group of materials with appealing qualities, including simplicity in fabrication, durability, and high transparency, and they play a crucial role in the optics field. In this paper, a new organic-inorganic metal halide luminescent glass exhibiting >78 % transmittance at 506-800 nm range together with a high photoluminescence quantum yield (PLQY) of 28.5 % is reported through a low-temperature melt-quenching approach of pre-synthesized (HTPP)2 MnBr4 (HTPP=hexyltriphenylphosphonium) single crystal. Temperature-dependent X-ray diffraction, polarizing microscopy, and molecular dynamics simulations were combined to investigate the glass-crystal interconversion process, revealing the disordered nature of the glassy state. Benefiting from the transparent nature, (HTPP)2 MnBr4 glass yields an outstanding spatial resolution of 10 lp mm-1 for X-ray imaging. The superb optical properties and facility of large-scale fabrication distinguish the organic-inorganic metal halide glass as a highly promising class of materials for optical devices.

6.
ACS Appl Mater Interfaces ; 14(42): 47913-47921, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36223523

RESUMO

Current X-ray imaging scintillators are dominated by inorganic scintillators grown through a high-temperature process. Exploring new types of scintillators with mild growth conditions, high light yields, and eco-friendly chemical compositions is essential and challenging. Herein, the zero-dimensional large-area laminar organic-inorganic hybrid metal halide TEA2MnI4 (TEA = tetraethylammonium) single crystal with dimensions of 50 mm × 60 mm × 0.82 mm is grown via a local-heating solvent evaporation method. Compared with its Cl- and Br-based counterparts, the incorporation of the iodine component enhances the X-ray attenuation ability and significantly accelerates the decay of the photoluminescence of TEA2MnI4. Interestingly, the prepared TEA2MnI4 exhibits a high transmittance of >90% over the range of 515-765 nm and exhibits a high light yield of 26288 photons/MeV, which provides the prerequisite for high-resolution X-ray imaging. The TEA2MnI4 single-crystal scintillator displays an astonishing spatial resolution exceeding 25 line pairs per millimeter, which provides a design concept for a Mn-I-based single crystal for high-performance scintillator applications.

7.
Sci Data ; 5: 180042, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29583142

RESUMO

To meet researchers' increasing interest in the fast growing innovation activities taking place in China, we match patents filed with China's State Intellectual Property Office to firms covered in China's Census. China has experienced a strong growth in patent filings over the past two decades, and has since 2011 become the world's top patent filing country. China's Census database covers about one million unique manufacturing firms from 1998-2009, representing the broad Chinese economy. We design data parsing and pre-processing routines to clean and stem firm and assignee names, create a matching algorithm that fits with our data and maintains a balance between matching accuracy and workload of manual check, and implement a systematic manual check process to filter out false positives generated from computerized matching. Our project generates 1,113,588 matches for the Census firms, among which 849,647 patents are uniquely matched. By creating the patent-firm linked dataset, we hope to reduce duplicative effort and encourage more research to better understand China's fast changing innovation landscape.

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