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In this paper we present a successful approach for the generation of partially fluorinated graphene structures. A computationally simple model optimized on a large density functional theory dataset quickly and precisely predicts experimentally observed structures. From the analysis of the structural diversity of fluorinated graphene in a wide range of synthesis temperatures, the general structural patterns are identified and the conditions for their achievement are determined. In addition, to facilitate further studies of fluorinated graphene, we present a ready-to-use GenCF code that implements the described structure generator.Covering up to August 2020The dramatic increase in the identification of dimeric natural products generated by microorganisms and plants has played a significant role in drug discovery. The biosynthetic pathways of these products feature inherent dimerization reactions, which are valuable for biosynthetic applications and chemical transformations. The extraordinary mechanisms of the dimerization of secondary metabolites should advance our understanding of the uncommon chemical rules for natural product biosynthesis, which will, in turn, accelerate the discovery of dimeric reactions and molecules in nature and provide promising strategies for the total synthesis of natural products through dimerization. This review focuses on the enzymes involved in the dimerization in the biosynthetic pathway of microbial natural products, with an emphasis on cytochrome P450s, laccases, and intermolecular [4 + 2] cyclases, along with other atypical enzymes. The identification, characterization, and catalytic landscapes of these enzymes are also introduced.Low-density lipoproteins (LDLs) are an endogenous nanocarrier to transport lipids in vivo. Owing to their biocompatibility and biodegradability, reduced immunogenicity, and natural tumor-targeting capability, we, for the first time, report the reconstitution of native LDL particles with saturated fatty acids and a mitochondrion-targeting aggregation-induced emission (AIE) photosensitizer for fluorescence-feedback photodynamic therapy (PDT). In particular, a novel AIE photosensitizer (TPA-DPPy) with a donor-acceptor (D-A) structure and a pyridinium salt is designed and synthesized, which possesses typical AIE and twisted intramolecular charge transfer (TICT) characteristics as well as reactive oxygen species (ROS)-sensitizing capability. In view of its prominent photophysical and photochemical properties, TPA-DPPy is encapsulated into LDL particles for photodynamic killing of cancer cells that overexpress LDL receptors (LDLRs). The resultant LDL (rLDL) particles maintain a similar morphology and size distribution to native LDL particles, and are efficiently ingested by cancer cells via LDLR-mediated endocytosis, followed by the release of TPA-DPPy for mitochondrion-targeting. Upon light irradiation, the produced ROS surrounding mitochondria lead to efficient and irreversible cell apoptosis. Interestingly, this process can be fluorescently monitored in a real-time fashion, as reflected by the remarkably enhanced luminescence and blue-shifted emission, indicating the increased mechanical stress during apoptosis. Quantitative cell viability analysis suggests that TPA-DPPy exhibits an outstanding phototoxicity toward LDLR-overexpressing A549 cancer cells, with a killing efficiency of ca. 88%. The rLDL particles are a class of safe and multifunctional nanophototheranostic agents, holding great promise in high-quality PDT by providing real-time fluorescence feedback on the therapeutic outcome.Restricting the aggregation and rationally adjusting the electronic structure of binary metal centers in metal-organic framework (MOF) precursors are important for optimizing their performance as electrocatalysts for the oxygen evolution reaction (OER) and achieving low overpotential and high stability in such applications. Herein, we demonstrate the possibility of enhancing the electrochemical activity of MOF-derived binary metal center catalysts by controlling the form of the Fe species. The introduction of Fe-SBU (iron 2,5-dihydroxyterephthalic acid) into ZIF-67 is found to induce a distinct confinement effect and this can be exploited to improve the electroconductivity of binary metal center catalysts, and therefore, to reduce the OER reaction barrier (OOH* → O*). When applied as an OER catalyst in 1 M KOH solution, the Fe-SBU@Co-Matrix catalyst exhibits a low overpotential of 249 mV to reach a current density of 10 mA cm-2 and high stability for over 40 h. This work describes the secondary growth treatment of MOF-derived porous carbons to promote their application as catalysts in energy conversion reactions.By analogy to heat and mass transfer film theory, a general approach is introduced for determining hyperpolarization transfer rates between dilute electron spins and a surrounding nuclear ensemble. These analyses provide new quantitative relationships for understanding, predicting, and optimizing the effectiveness of hyperpolarization protocols, such as Dynamic Nuclear Polarization (DNP) under magic-angle spinning conditions. An empirical DNP polarization-transfer coefficient is measured as a function of the bulk matrix 1H spin density and indicates the presence of two distinct kinetic regimes associated with different rate-limiting polarization transfer phenomena. Dimensional property relationships are derived and used to evaluate the competitive rates of spin polarization generation, propagation, and dissipation that govern hyperpolarization transfer between large coupled spin ensembles. The quantitative analyses agree closely with experimental measurements for the accumulation, propagation, and dissipation of hyperpolarization in solids and provide evidence for kinetically-limited transfer associated with a spin-diffusion barrier. selleck The results and classical approach yield general design criteria for analyzing and optimizing polarization transfer processes involving complex interfaces and composite media for applications in materials science, physical chemistry and nuclear spintronics.