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Tingting Li,1,2,* Xiaoming Hu,3,* Quli Fan,4,* Zejing Chen,3 Ziliang Zheng,1 Ruiping Zhang2 1Department of Pharmacy, School of Pharmaceutical Science, Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of China; 2Radiology Department, The Affiliated Bethune Hospital of Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of China; 3Institute of Advanced Materials, East China Jiaotong University, Nanchang, Jiangxi, People’s Republic of China; 4Key Laboratory for Organic Electronics & Information Displays and Institute of Advanced Materials, Nanjing University of Posts & Telecommunications, Nanjing, Jiangsu, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ruiping ZhangRadiologyDepartment, The Affiliated Bethune Hospital of Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of ChinaEmail zrp_7142@sxmu.edu.cnBackground: Molecular imaging is of great benefit to early disease diagnosis and timely treatment. One of the most striking innovations is the development of multimodal molecular imaging technology, which integrates two or more imaging modalities, largely in view of making the best of the advantages of each modality while overcoming their respective shortcomings. Hence, engineering a versatile and easily prepared nanomaterial with integrating multimodal molecular imaging function holds great promise, but is still a great challenge.Materials and Methods: We firstly designed and synthesized a BDT-DPP conjugated polymer and then noncovalent self-assembly with phospholipid-polyethylene glycol endowed BDT-DPP with water solubility and biocompatibility. Followed by [Cu] labeling, the acquired multifunctional nanoparticles (NPs) were studied in detail for the photophysical property. The cytotoxicity and biocompatibility of DPP-BDT NPs were examined through MTT assay and H&E stained analysis. In addition, we investigated the accumulation of the NPs in HepG2 tumor models by positron emission tomography (PET) and photoacoustic (PA) dual-mode imaging.Results and Discussion: The DPP-BDT NPs exhibited excellent optical stability, strong near-infrared (NIR) light absorption as well as fine biocompatibility. After tail vein injection into the living mice, the PA signals in the neoplastic tissues were gradually increased and reached to the maximum at the 4-h post-injection, which was consistent with the PET analysis. Such strong PA and PET signals were attributed to the efficient NPs accumulation resulting from the enhanced permeability and retention (EPR) effect.Conclusion: The biocompatible DPP-BDT NPs demonstrated to be strong NIR absorption property and PAI sensitivity. Besides, these novel DPP-BDT NPs can act not only as a PA imaging contrast agent but also as an imaging agent for PET.Keywords: conjugated polymer, nanoparticles, photoacoustic imaging, positron emission tomography imaging

Ethanol steam reforming (ESR) on a group of multifunctional xFeyCu10Ni-Beta catalysts was studied using in X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), temperature-programmed reduction in hydrogen (H2-TPR), temperature-programmed oxidation (TPO), and X-ray absorption fine structure (XAFS) techniques with a focus on the structural characterization of the active sites, the effect of different amounts of Cu and Fe phases and understanding the reaction pathway for the catalysts. The 1.5Fe1.5Cu10Ni-Beta catalyst exhibited very good catalytic performance for the ESR, including high activity, high H2 selectivity, and low undesired products, because of the synergistic catalysis of Ni, Cu, and Fe phases. The Cu site preferentially facilitates the dehydrogenation of ethanol at the initial reaction step, and with subsequent Ni metal catalyzes dissociation of the C–C bond in acetaldehyde to form CO and CH4. The Fe phase, which has a tendency to be enrich...

BEA-type core–shell catalysts consisting of a core supporting Cu and Fe and a Ni-based shell were investigated for their ethanol steam reforming (ESR) activity. The effect of the nature of the core–shell double-support and the promotion achieved by adding Ni, Cu and Fe were studied. The catalysts were characterized by XRD, BET, SEM, TEM, H2-TPR, CH4-TPD, CO-TPD and XAFS analyses. Compared to zeolite Beta as support, the core–shell catalysts exhibited excellent performance in ethanol reforming, leading to high selectivity to hydrogen through a multiple reaction system. This result indicated that the special structural advantages of the core–shell support could give full play to the properties of active phases and provide a one-step production process for high-purity hydrogen. The Ni-base shell was twice as active for the catalytic reaction, resulting in greatly improved catalytic activity and selectivity to hydrogen; in addition, the decrease of by-products could be attributed to the function of the Cu and Fe phases, improving the steam acetaldehyde reforming, steam methane reforming and water gas shift reactions. Furthermore, in the investigation of the effects of the amount of the Cu and Fe phases, the best catalytic performance was reported by the 2.5Fe2.5Cu-SB@NB catalyst.

A novel platinum-encapsulated hollow Beta zeolite (Pt@HBS) catalyst was successfully fabricated through an organotemplate-free and seed-directed route, with carbon spheres as a hard template. Pt@HBS not only exhibited excellent catalytic performance, but could also maintain the catalytic reaction for more than 28 h without losing its activity.