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Organic transformation by light-driven catalysis, especially, photocatalysis and photothermal catalysis, denoted as photo(thermal) catalysis, is an efficient, green, and economical route to produce value-added compounds. In recent years, owing to their diverse structure types, tunable pore sizes, and abundant active sites, metal–organic framework (MOF)-based photo(thermal) catalysis has attracted broad interest in organic transformations. In this review, we provide a comprehensive and systematic overview of MOF-based photo(thermal) catalysis for organic transformations. First, the general mechanisms, unique advantages, and strategies to improve the performance of MOFs in photo(thermal) catalysis are discussed. Then, outstanding examples of organic transformations over MOF-based photo(thermal) catalysis are introduced according to the reaction type. In addition, several representative advanced characterization techniques used for revealing the charge reaction kinetics and reaction intermediates of MOF-based organic transformations by photo(thermal) catalysis are presented. Finally, the prospects and challenges in this field are proposed. This review aims to inspire the rational design and development of MOF-based materials with improved performance in organic transformations by photocatalysis and photothermal catalysis. [ABSTRACT FROM AUTHOR]

Exploring the photocatalytic application of cerium‐based metal–organic frameworks (Ce‐MOFs) has attracted special interest due to the high abundance, low cost, and easy availability of Ce as well as the presence of low energy 4f orbitals and redox Ce (III)/(IV) couple. However, in contrast to the recent emerging study on the development of Ce (IV)‐MOFs as photocatalysts, there are few reports focusing on the photocatalytic performance of Ce (III)‐MOFs. Meanwhile, research on comparing the photocatalytic properties of rare‐earth lanthanide (Ln) ions has rarely been reported. Herein, a novel Ce (III)‐MOF with a formula of (Ce)6(BDC)9(DMF)6(H2O)3·(DMF)3, named CSUST‐4 (CSUST stands for Changsha University of Science and Technology), was successfully synthesized and characterized. The comprehensive analysis of the Ce‐O distance and Ce 3d spectra of CSUST‐4, mixed‐valence Ce (III/IV)‐MOF CSUST‐1, and Ce (IV)‐MOF CSUST‐3 demonstrated that the Ce‐O distance (O from the oxo bridge) can be used as an important reference to assign the valence state of Ce in Ce‐MOFs while the satellite peak around 916.0 eV attributed to Ce (IV) can be utilized to distinguish Ce (IV)‐containing Ce‐MOFs from Ce (III)‐MOFs. Furthermore, the photocatalytic hydrogen evolution (PHE) property of CSUST‐4 by water splitting was also studied, and by utilizing isostructural MOFs CSUST‐4‐Ln (Ln = La, Nd, Eu, Er, Yb) as platforms, the PHE performances of these Ln ions were compared, which evidenced that Ce is a suitable Ln ion to construct MOF materials for PHE in terms of cost and performance. This work contributes to the development of the Ce‐MOF field as well as sheds light on advancing Ce (III)‐MOFs toward potential photocatalytic application. [ABSTRACT FROM AUTHOR]

Mycoplasma ovipneumoniae is considered as an important pathogen of small ruminants, but its antigenic proteins are not well known so far. In this study, we cloned the EF-Tu gene of M. ovipneumoniae and analyzed the molecular features of the gene and its coding protein for the first time. The gene was then expressed in E.coli and the antigenicity of the coding protein was evaluated as well. The EF-Tu gene of M. ovipneumoniae is 1209 bp in length, encodes 402 amino acids, and shares the highest DNA sequence identity of 87.5% and deduced amino acid sequence identity of 97.8% with those of M. hyopneumoniae, respectively. The recombinant EF-Tu protein can react with the polyclonal antiserum of M. ovipneumoniae and can induce humoral immune responses in mice, which indicated that the EF-Tu may be used as a candidate protein in developing the technologies to control the disease.

The wind past the ship superstructure produces an unsteady turbulent airwake which has a significant effect on aircraft performance and consequently pilot workload during ship landing process. Computational fluid dynamics simulations of a generic simple frigate shape ship airwake have been performed using the entropy-based detached-eddy simulation method. The results were compared with the steady-state Reynolds-averaged Navier–Stokes calculations and the wind tunnel data, indicating the capability of entropy-based detached-eddy simulation to resolve the unsteady large-scale turbulent features. An analysis of the airwake flow topology at headwind condition highlights the vortex pairing process which dominates the flowfield above the deck. Additionally, the influence of hangar-door state (open, closed or half-open) on the airwake was also investigated in detail. Determination of this complex flow can assist in the definition of safe ship–helicopter operating limits and future ship design.

Codonopsis radix was commonly used as food materials or herbal medicines in many countries. However, the comprehensive analysis of chemical constituents, and in vivo xenobiotics of Codonopsis radix remain unclear. In the present study, an integrated strategy with feature‐based molecular networking using ultra‐high‐performance liquid chromatography coupled with mass spectrometry was established to systematically screen the chemical constituents and the in vivo xenobiotics of Codonopsis radix. A step‐by‐step manner based on a composition database, visual structure classification, discriminant ions, and metabolite software prediction was proposed to overcome the complexities due to the similar structure of chemical constituents and metabolites of Codonopsis radix. As a result, 103 compounds were tentatively characterized, 20 of which were identified by reference standards. Besides, a total of 50 xenobiotics were detected in vivo, including 26 prototypes and 24 metabolites, while the metabolic features of the pyrrolidine alkaloids were elucidated for the first time. The metabolism reactions of pyrrolidine alkaloids and sesquiterpene lactones included oxidation, methylation, hydration, hydrogenation, demethylation, glucuronidation, and sulfation. This study provided a generally applicable approach to the comprehensive investigation of the chemical and metabolic profile of traditional Chinese medicine and offered reasonable guidelines for further screening of quality control indicators and pharmacodynamics mechanism of Codonopsis radix. [ABSTRACT FROM AUTHOR]