Interfaces between MoO x and Mo X2(X=S,Se,and Te)

In the past decades there have been many breakthroughs in low-dimensional materials,especially in two-dimensional(2D)atomically thin crystals like graphene.As structural analogues of graphene but with a sizeable band gap,monolayers of atomically thin transition metal dichalcogenides(with formula of MX2,M=Mo,W;X=S,Se,Te,etc.)have emerged as the ideal 2D prototypes for exploring fundamentals in physics such as valleytronics due to the quantum confinement effects,and for engineering a wide range of nanoelectronic,optoelectronic,and photocatalytic applications.Transition metal trioxides as promising materials with low evaporation temperature,high work function,and inertness to air have been widely used in the fabrication and modification of MX2.In this review,we reported the fabrications of one-dimensional MoS2 wrapped MoO2 single crystals with varied crystal direction via atmospheric pressure chemical vapor deposition method and of 2D MoOx covered MoX2 by means of exposing MoX2 to ultraviolet ozone.The prototype devices show good performances.The approaches are common to other transition metal dichalcogenides and transition metal oxides.

Molecular imaging:design mechanism and bioapplications

Molecular imaging is a non-invasive method to image and analyze the concentration and activity of functional biomolecules in cells or in vivo at molecular level,and plays an increasing role in deep understanding of biological processes,early and accurate diagnosis of diseases,and evaluation of treatment.Nowadays,numerous novel molecular imaging probes have been developed,involving every biomedical imaging modality,such as optical imaging,photoacoustic imaging,magnetic resonance imaging,single-photon-emission computed tomography,and positron emission tomography.In this review,we summarize the development of current state-of-the-art molecular imaging probes.We introduce the design strategies of molecular probes and detailed imaging modalities,and highlight the properties of probes and biomedical imaging applications in cells and in vivo,including disease diagnosis,drug tracking,and imaging-guided surgery.Then we discuss the perspectives and challenges in this emerging field.We expect this review could inspire more effective molecular imaging probes to be developed,achieving the goal towards clinical practices.

Multiple characteristic structure fragments scans coupled to high-resolution mass spectrometry strategy for discovering unknown structural analogs of mycotoxins in food

The cereals and their products,which have been easily infected by fungi and contaminated with mycotoxins,are serious threat to both human and animals alike.And yet,detection of these unknown fungal infection and mycotoxins contaminates remains a great challenge.In this work,a holistic approach based on multiple characteristic structure fragments scans and high-resolution mass spectrometry(HRMS)was proposed for discovering unknown structural analogues of mycotoxins.The structural similarity of the same class of compounds provides a direction for the discovery and identification of unknown structural analogues of mycotoxins.The following steps were carried out:the fragmentation pathways of four types of mycotoxins were elucidated through comprehensive fragment analysis.By the combination of fragmentation pathways,the multiple characteristic structure fragments were screened out,with the common fragments were obtained by Veen diagram.Finally multiple characteristic structure fragments scans were carried out to find the unknown structural analogues of mycotoxins.The approach,first proposed by us,was proved to be effective in discovering and identifying 5 structural analogues of mycotoxins in real samples.It was proved to be a simple,fast and accurate method for early detection of fungal infection and mycotoxin contaminants,even for trace amounts of chemicals in complex matrix,and is of great significance to prevent hazardous substances infection from the food supply chains worldwide.