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1.
Adv Sci (Weinh) ; 8(24): e2102376, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34693667

RESUMO

The techniques for the production of the environment have received attention because of the increasing air pollution, which results in a negative impact on the living environment of mankind. Over the decades, burgeoning interest in polymeric carbon nitride (PCN) based photocatalysts for heterogeneous catalysis of air pollutants has been witnessed, which is improved by harvesting visible light, layered/defective structures, functional groups, suitable/adjustable band positions, and existing Lewis basic sites. PCN-based photocatalytic air purification can reduce the negative impacts of the emission of air pollutants and convert the undesirable and harmful materials into value-added or nontoxic, or low-toxic chemicals. However, based on previous reports, the systematic summary and analysis of PCN-based photocatalysts in the catalytic elimination of air pollutants have not been reported. The research progress of functional PCN-based composite materials as photocatalysts for the removal of air pollutants is reviewed here. The working mechanisms of each enhancement modification are elucidated and discussed on structures (nanostructure, molecular structue, and composite) regarding their effects on light-absorption/utilization, reactant adsorption, intermediate/product desorption, charge kinetics, and reactive oxygen species production. Perspectives related to further challenges and directions as well as design strategies of PCN-based photocatalysts in the heterogeneous catalysis of air pollutants are also provided.

2.
Chem Commun (Camb) ; 55(75): 11259-11262, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31475259

RESUMO

A new type of base catalyst was designed and prepared by metalation of carbon nitrides with alkali metal ions. The as-prepared metalated carbon nitride composites showed enhanced basicity and efficient catalytic hydrolysis of carbonyl sulfide. The results of this study demonstrate that the metalation of carbon nitrides holds great promise for base catalysis applications.

3.
Viruses ; 11(8)2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370205

RESUMO

An emerging virus-like flower yellowing disease (FYD) of green Sichuan pepper (Zanthoxylum armatum v. novemfolius) has been recently reported. Four new RNA viruses were discovered in the FYD-affected plant by the virome analysis using high-throughput sequencing of transcriptome and small RNAs. The complete genomes were determined, and based on the sequence and phylogenetic analysis, they are considered to be new members of the genera Nepovirus (Secoviridae), Idaeovirus (unassigned), Enamovirus (Luteoviridae), and Nucleorhabdovirus (Rhabdoviridae), respectively. Therefore, the tentative names corresponding to these viruses are green Sichuan pepper-nepovirus (GSPNeV), -idaeovirus (GSPIV), -enamovirus (GSPEV), and -nucleorhabdovirus (GSPNuV). The viral population analysis showed that GSPNeV and GSPIV were dominant in the virome. The small RNA profiles of these viruses are in accordance with the typical virus-plant interaction model for Arabidopsis thaliana. Rapid and sensitive RT-PCR assays were developed for viral detection, and used to access the geographical distributions. The results revealed a correlation between GSPNeV and the FYD. The viruses pose potential threats to the normal production of green Sichuan pepper in the affected areas due to their natural transmission and wide spread in fields. Collectively, our results provide useful information regarding taxonomy, transmission and pathogenicity of the viruses as well as management of the FYD.


Assuntos
Genoma Viral , Filogenia , Doenças das Plantas/virologia , Vírus de Plantas/classificação , Vírus de RNA/genética , Zanthoxylum/virologia , Luteoviridae/classificação , Luteoviridae/isolamento & purificação , Nepovirus/classificação , Nepovirus/isolamento & purificação , Fases de Leitura Aberta , Vírus de Plantas/isolamento & purificação , Vírus de RNA/isolamento & purificação , RNA Viral/genética , Rhabdoviridae/classificação , Rhabdoviridae/isolamento & purificação
4.
Opt Express ; 22 Suppl 5: A1334-42, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25322188

RESUMO

In this study, the design and fabrication schemes of back-side illuminated InGaN/GaN solar cells with periodic via-holes etching and Bragg mirror processes are presented. Compared to typical front-side illuminated solar cells, the improvements of open-circuit voltage (V(oc)) from 1.88 to 1.94 V and short-circuit current density (J(sc)) from 0.84 to 1.02 mA/cm(2) are observed. Most significantly, the back-side illuminated InGaN/GaN solar cells exhibit an extremely high fill factor up to 85.5%, leading to a conversion efficiency of 1.69% from 0.66% of typical front-side illuminated solar cells under air mass 1.5 global illuminations. Moreover, the effects of bottom Bragg mirrors on the photovoltaic characteristics of back-side illuminated solar cells are studied by an advanced simulation program. The results show that the J(sc) could further be improved with a factor of 10% from the original back-side illuminated solar cell by the structure optimization of bottom Bragg mirrors.

5.
Int J Mol Sci ; 13(9): 11455-11470, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23109865

RESUMO

The Jinchuan yak is a new yak population identified in Sichuan, China. This population has a special anatomical characteristic: an additional pair of ribs compared with other yak breeds. The genetic structure of this population is unknown. In the present study, we investigated the maternal phylogeny of this special yak population using the mitochondrial DNA variation. A total of 23 Jinchuan yaks were sequenced for a 823-bp fragment of D-loop control region and three individuals were sequenced for the whole mtDNA genome with a length of 16,371-bp. To compare with the data from other yaks, we extracted sequence data from Genebank, including D-loop of 398 yaks (from 12 breeds) and 55 wild yaks, and whole mitochondrial genomes of 53 yaks (from 12 breeds) and 21 wild yaks. A total of 127 haplotypes were defined, based on the D-loop data. Thirteen haplotypes were defined from 23 mtDNA D-loop sequences of Jinchuan yaks, six of which were shared only by Jinchuan, and one was shared by Jinchuan and wild yaks. The Jinquan yaks were found to carry clades A and B from lineage I and clade C of lineage II, respectively. It was also suggested that the Jinchuan population has no distinct different phylogenetic relationship in maternal inheritance with other breeds of yak. The highly haplotype diversity of the Pali breed, Jinchuan population, Maiwa breed and Jiulong breed suggested that the yak was first domesticated from wild yaks in the middle Himalayan region and the northern Hengduan Mountains. The special anatomic characteristic that we found in the Jinchuan population needs further studies based on nuclear data.


Assuntos
Bovinos/genética , DNA Mitocondrial/genética , Haplótipos/genética , Polimorfismo de Fragmento de Restrição/genética , Análise de Sequência de DNA/veterinária , Animais , Sequência de Bases , Bovinos/anatomia & histologia , China , Feminino , Mitocôndrias/genética , Dados de Sequência Molecular , Filogenia
6.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1901, 2009 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-21583591

RESUMO

In the title compound, C(31)H(32)BrN(3)O(3), the morpholine ring adopts a chair conformation, and the planar quinoline system is twisted with respect to the phenyl rings, with dihedral angles of 17.6 (4) and 75.1 (3)°. Intramolecular C-H⋯O and C-H⋯N hydrogen bonds are present. The crystal packing is stabilized by weak C-H⋯O hydrogen bonding and C-H⋯π interactions.

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