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1.
Angew Chem Int Ed Engl ; 63(10): e202318735, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38108581

ABSTRACT

Covalent organic frameworks (COFs) have been widely studied in photocatalytic CO2 reduction reaction (CO2 RR). However, pristine COFs usually exhibit low catalytic efficiency owing to the fast recombination of photogenerated electrons and holes. In this study, we fabricated a stable COF-based composite (GO-COF-366-Co) by covalently anchoring COF-366-Co on the surface of graphene oxide (GO) for the photocatalytic CO2 reduction. Interestingly, in absolute acetonitrile (CH3 CN), GO-COF-366-Co shows a high selectivity of 94.4 % for the photoreduction of CO2 to formate, with a formate yield of 15.8 mmol/g, which is approximately four times higher than that using the pristine COF-366-Co. By contrast, in CH3 CN/H2 O (v : v=4 : 1), the main product for the photocatalytic CO2 reduction over GO-COF-366-Co is CO (96.1 %), with a CO yield as high as 52.2 mmol/g, which is also approximately four times higher than that using the pristine COF-366-Co. Photoelectrochemical experiments demonstrate the covalent bonding of COF-366-Co and GO to form the GO-COF-366-Co composite facilitates charge separation and transfer significantly, thereby accounting for the enhanced catalytic activity. In addition, theoretical calculations and in situ Fourier transform infrared spectroscopy reveal H2 O can stabilize the *COOH intermediate to further form a *CO intermediate via O-H(aq)⋅⋅⋅O(*COOH) hydrogen bonding, thus explaining the regulated photocatalytic performance.

2.
Inorg Chem ; 62(29): 11611-11617, 2023 Jul 24.
Article in English | MEDLINE | ID: mdl-37428154

ABSTRACT

The development of hierarchically porous metal-organic frameworks (MOFs) with high stability is desirable to expand their applications but remains challenging. Herein, an anionic sodalite-type microporous MOF (Yb-TTCA; TTCA3- = triphenylene-2,6,10-tricarboxylate) was synthesized, which shows outstanding catalytic activities for the cycloaddition of CO2 into cyclic carbonates. Moreover, the microporous Yb-TTCA can be transformed into a hierarchical micro- and mesoporous Yb-TTCA by water treatment with the mesopore sizes of 2 to 12 nm. The hierarchically porous Yb-TTCA (HP-Yb-TTCA) not only exhibits a high thermal stability up to 500 °C but also shows a high chemical stability in aqueous solutions with pH values ranging from 2 to 12. In addition, the HP-Yb-TTCA displays enhanced performance for the removal of organic dyes in comparison with microporous Yb-TTCA. This work provides a facile way to construct hierarchically porous MOF materials.

3.
Proc Natl Acad Sci U S A ; 119(11): e2118278119, 2022 03 15.
Article in English | MEDLINE | ID: mdl-35263220

ABSTRACT

SignificanceThe photosensitizer is one of the important components in the photocatalytic system. Molecular photosensitizers have well-defined structures, which is beneficial in revealing the catalysis mechanism and helpful for further structural design and performance optimization. However, separation and recycling of the molecular photosensitizers is a great problem. Loading them into/on two/three-dimensional supports through covalent bonds, electrostatic interactions, and supramolecular interactions is a method that enhances their separation and recycling capability. Nonetheless, the structures of the resulting composites are unclear. Thus, the development of highly crystalline heterogeneity methods for molecular photosensitizers, albeit greatly challenging, is meaningful and desirable in photocatalysis, through which heterogeneous photosensitizers with well-defined structures, definite catalysis mechanisms, and good catalytic performance would be expected.


Subject(s)
Photosensitizing Agents , Catalysis , Molecular Structure , Photosensitizing Agents/chemistry
4.
Crit Rev Food Sci Nutr ; 62(23): 6374-6389, 2022.
Article in English | MEDLINE | ID: mdl-33739226

ABSTRACT

Condiments are the magical ingredients that make the food present a richer taste. In recent years, due to the increasing consciousness of food safety and human health, much progress has been made in developing rapid and nondestructive techniques for the evaluation of food condiments safety, authentication, and traceability. The potential of spectroscopy techniques, such as near-infrared (NIR), mid-infrared (MIR), Raman, fluorescence, inductively coupled plasma (ICP), and hyperspectral imaging techniques, has been widely enhanced by numerous applications in this field because of their advantages over other analytical techniques. Following a brief introduction of condiment and safety basics, this review mainly focuses on recent vibrational and atomic spectral applications for condiment nondestructive analysis and evaluation, including (1) chemical hazards detection; (2) microbiological hazards detection; and (3) authenticity concerns. The review shows current spectroscopies to be effective tools that will play indispensable roles for food condiment evaluation. In addition, online/real-time applications of these techniques promise to be a huge growth field in the near future.


Subject(s)
Food Safety , Spectroscopy, Near-Infrared , Condiments , Humans , Spectroscopy, Near-Infrared/methods , Vibration
5.
Inorg Chem ; 60(19): 14924-14931, 2021 Oct 04.
Article in English | MEDLINE | ID: mdl-34529419

ABSTRACT

The exploitation of highly stable and active catalysts for the conversion of CO2 into valuable fuels is desirable but is a great challenge. Herein, we report that the incorporation of chromophores into metal-organic frameworks (MOFs) could afford robust catalysts for efficient CO2 conversion. Specifically, a porous Nd(III) MOF (Nd-TTCA; TTCA3- = triphenylene-2,6,10-tricarboxylate) was constructed by incorporating one-dimensional Nd(CO2)n chains and TTCA3- ligands, which exhibits a very high stability, retaining its framework not only in the air at 300 °C for 2 h but also in boiling aqueous solutions at pH 1-12 for 7 days. More importantly, Nd-TTCA has achieved a 5-fold improvement in photocatalytic activity for reducing CO2 to HCOOH and a 10-fold improvement in catalytic activity for the cycloaddition of CO2 into cyclic carbonate in comparison to those of H3TTCA itself. This work gives a new strategy to design efficient artificial crystalline catalysts for CO2 conversion.

6.
J Occup Health ; 58(5): 482-488, 2016 Sep 30.
Article in English | MEDLINE | ID: mdl-27488044

ABSTRACT

OBJECTIVES: Occupational exposure to paraffin is an infrequent cause of lipoid pneumonia (LP) and related data are scare. We investigated the possible relationship between three rare cases of chronic LP and occupational exposure to paraffin aerosol in an iron foundry. METHODS: The three cases of LP and their workplaces were investigated using data from field investigations, air monitoring, pulmonary radiological examinations, cell staining, and lung biopsies. RESULTS: The patients had long-term occupational exposure to paraffin. X-ray diffraction testing revealed that the raw material from the workshop was paraffin crystal. The air concentrations of paraffin aerosol in workplaces were significantly higher than outdoor background levels. Small diffuse and miliary shadows with unclear edges were observed throughout the whole lungs via radiography. Computed tomography revealed diffuse punctate nodules and a high density of stripe-like shadows in both lungs (ground-glass opacity in a lower lobe, and a mass-like lesion and high translucent area near the bottom of the lung). Lipid-laden macrophages were found in the sputum and bronchial lavage. A broadened alveolar septum and local focal fibrosis were also discovered via lung biopsy. The inflammatory reaction in the lung tissues appeared to resolve over time. CONCLUSIONS: These three rare cases of chronic LP in workers during molding and repair processes were associated with occupational paraffin aerosol exposure. Therefore, primary prevention is essential for molding or repairing workers in the iron foundry, and a differential diagnosis of occupational chronic LP (vs. pneumoconiosis) should be considered when treating these workers.


Subject(s)
Occupational Diseases/chemically induced , Occupational Exposure/adverse effects , Paraffin/adverse effects , Pneumonia, Lipid/chemically induced , Adult , Aerosols/adverse effects , China , Female , Humans , Manufacturing and Industrial Facilities , Middle Aged , Occupational Exposure/analysis , Paraffin/analysis , Pneumonia, Lipid/diagnostic imaging , Pneumonia, Lipid/pathology
7.
Article in Chinese | MEDLINE | ID: mdl-24822367

ABSTRACT

OBJECTIVE: To identify the sources of infection and the mode of transmission of a malaria case with unknown origin. METHODS: Clinical data of the case were collected and the epidemiological investigation was conducted. The blood samples of the patient and the suspected infection source (blood donor) were detected by microscopy, rapid diagnostic test strip (RDT) and nested PCR. RESULTS: The patient did not visited malaria endemic areas. After a blood transfusion, the patient had chills and fever, and was confirmed as falciparum malaria by microscopy with bone marrow and peripheral blood smears and RDT. The blood donor was a worker returned from Africa. Before blood donation she was sick like malaria carrier, and took anti-malarial drug. She was then confirmed as falciparum malaria by RDT and microscopy. The blood samples from the patient and the blood donor were diagnosed as falciparum malaria by nested PCR, and the similarity of the small subunit rRNA (SSU rRNA) sequence was 100%, showing they were mix-infected with K1 and MAD20 genotypes of Plasmodium falciparum. CONCLUSION: This patient is confirmed P. falciparum infection via blood transfusion from a donor who returned from Africa.


Subject(s)
Malaria, Falciparum/diagnosis , Plasmodium falciparum/isolation & purification , Antimalarials/therapeutic use , Female , Humans , Malaria , Malaria, Falciparum/drug therapy , Malaria, Falciparum/transmission , Microscopy , Polymerase Chain Reaction , Transfusion Reaction
8.
Article in Chinese | MEDLINE | ID: mdl-24812847

ABSTRACT

Blood sample obtained from a patient, which returned from Equatorial Guinea, with clinical diagnosis of Plasmodium infection was confirmed as imported P. ovale infection by etiology and molecular biological methods. 50 microl blood was obtained before taking anti-malarial drugs to make thin and thick blood smears, Giemsa stained, and observed by microscopy. Genomic DNA was extracted from the blood sample, and detected for DNA fragment of P. ovale, P. vivax, P. falciparum or P. malariae by real-time fluorescent quantitative PCR. P. ovale parasites were found in both thin and thick blood smears, and confirmed by quantitative PCR. With the results of laboratory testing, epidemiological history and clinical manifestations, the patient was diagnosed as imported P. ovale infection.


Subject(s)
Malaria/parasitology , Plasmodium ovale/genetics , Adult , China , DNA, Protozoan/analysis , Humans , Malaria/diagnosis , Male , Polymerase Chain Reaction
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(4): 344-7, 2009 Apr.
Article in Chinese | MEDLINE | ID: mdl-19731524

ABSTRACT

OBJECTIVE: To understand the prevalence of rabies among wild animals and the animal species in rabies epidemic areas of Zhejiang province. METHODS: One hundred and sixty samples were collected from the brain tissues of cats, stoats, Apodemus agrarius, Moschus chinensis, and Sus scrofa in Lishui and Chunan cities of Zhejiang province. Each sample was divided into four parts: cerebrum, mesencephali, cerebellum and gyms hippocampi which were used to determine the positive samples by detection of rabies virus specific antigens and nucleotides, using DFA and RT-PCR methods. RESULTS: Positive slides in the tests contained a glaring, apple green brilliance fluorescence using rabies virus specific monoclonal antibody against nucleoprotein. Using Nested-PCR method targeted at part of N gene, five positive samples were identified which consisting of four positive samples from stoats with positive ratio as 8.33% (4/48) and one positive sample from Apodemus agrarius with positive ratio as 1.75% (1/57). However, no positive result was found from cats, Moschus chinensis, and Sus scrofa samples. CONCLUSION: Rabies virus positive samples were identified from stoats and Apodemus agrarius in the mountain areas, with biological diversity in Lishui and Chunan cities of Zhejiang province, indicating that stoats and Apodemus agrarius might have played a role in human rabies and acted as host of rabies virus. In order to effectively prevent and control rabies virus under these complicated geographical and ecological environment, we must understand and evaluate the infection situation among animals in these regions.


Subject(s)
Brain/virology , Rabies virus/isolation & purification , Rabies/veterinary , Animals , Antigens, Viral/analysis , Cats/virology , China/epidemiology , Mustelidae/virology , RNA, Viral/genetics , Rabies/epidemiology , Rabies/prevention & control , Rabies/virology , Rabies virus/genetics , Swine/virology
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(8): 824-8, 2009 Aug.
Article in Chinese | MEDLINE | ID: mdl-20193207

ABSTRACT

OBJECTIVE: Based on sequencing the full-length genomes of two Chinese Ferret-Badger, we analyzed the properties of rabies viruses genetic variation in molecular level to get information on prevalence and variation of rabies viruses in Zhejiang, and to enrich the genome database of rabies viruses street strains isolated from Chinese wildlife. METHODS: Overlapped fragments were amplified by RT-PCR and full-length genomes were assembled to analyze the nucleotide and deduced protein similarities and phylogenetic analyses of the N genes from Chinese Ferret-Badger, sika deer, vole, dog. Vaccine strains were then determined. RESULTS: The two full-length genomes were completely sequenced to find out that they had the same genetic structure with 11 923 nts including 58 nts-Leader, 1353 nts-NP, 894 nts-PP, 609 nts-MP, 1575 nts-GP, 6386 nts-LP, and 2, 5, 5 nts- intergenic regions (IGRs), 423 nts-Pseudogene-like sequence (Psi), 70 nts-Trailer. CONCLUSION: The two full-length genomes were in accordance with the properties of Rhabdoviridae Lyssa virus by blast and multi-sequence alignment. The nucleotide and amino acid sequences among Chinese strains had the highest similarity, especially among animals of the same species. Of the two full-length genomes, the similarity in amino acid level was dramatically higher than that in nucleotide level, so that the nucleotide mutations happened in these two genomes were most probably as synonymous mutations. Compared to the referenced rabies viruses, the lengths of the five protein coding regions did not show any changes or recombination, but only with a few-point mutations. It was evident that the five proteins appeared to be stable. The variation sites and types of the two ferret badgers genomes were similar to the referenced vaccine or street strains. The two strains were genotype 1 according to the multi-sequence and phylogenetic analyses, which possessing the distinct geographyphic characteristics of China. All the evidence suggested a cue that these two ferret badgers rabies viruses were likely to be street virus that already circulating in wildlife.


Subject(s)
Disease Reservoirs/veterinary , Genome, Viral , Mustelidae/virology , Rabies virus/genetics , Animals , Arvicolinae/virology , China , Deer/virology , Disease Reservoirs/virology , Dogs/virology , Molecular Sequence Data , Mutation , Phylogeny , Rabies virus/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction , Viral Proteins/genetics
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