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Connell posted an update 7 months, 1 week ago
Molten alkali-metal carbonates and hydroxides play important roles in the molten carbonate fuel cell and in Earth’s geochemistry. Molecular simulations allow us to study these systems at extreme conditions without the need for difficult experimentation. Using a genetic algorithm to fit ab intio molecular dynamics-computed densities and radial distribution functions, as well as experimental enthalpies of formation, we derive new classical force fields able to accurately predict liquid chemical potentials. These fitting properties were chosen to ensure accurate liquid phase structure and energetics. Although the predicted dynamics is slow when compared to experiments, in general the trends in dynamic properties across different systems still hold true. In addition, these newly parametrized force fields can be extended to the molten carbonate-hydroxide mixtures by using standard combining rules.Sénéchal et al. presented a Comment to our article published in [ Biomacromolecules 2014, 15, 1194-1203] and entitled “N-terminal Protein Tail Acts as Aggregation Protective Entropic Bristles The SUMO Case”, and here we provide our reply.An electrophilic enantioselective catalytic method for the α-pentafluoroethylation of 3-oxoesters is described. Under the use of La(OTf)3 in combination with a (S,R)-indanyl-pybox ligand, good results in terms of yield and enantioselectivities were achieved (up to 89% ee). The reaction proceeds under mild conditions, leading to the formation of enantioenriched quaternary centers. This methodology uses an hypervalent iodine(III)-CF2CF3 reagent, and mechanistic investigations are consistent with the involvement of a radical pathway.A new mode of bond activation involving M→Z interactions is disclosed. CDK inhibition Coordination to transition metals as σ-acceptor ligands was found to enable the activation of fluorosilanes, opening the way to the first transition-metal-catalyzed Si-F bond activation. Using phosphines as directing groups, sila-Negishi couplings were developed by combining Pd and Ni complexes with external Lewis acids such as MgBr2. Several key catalytic intermediates have been authenticated spectroscopically and crystallographically. Combined with DFT calculations, all data support cooperative activation of the fluorosilane via Pd/Ni→Si-F→Lewis acid interaction with conversion of the Z-type fluorosilane ligand into an X-type silyl moiety.Magnetic hyperthermia therapy (MHT) has been considered as an excellent alternative for treatment of deep tumor tissue; however, up-regulation of heat shock proteins (HSPs) impairs its hyperthermal therapeutic effect. Reactive oxygen species (ROS) and competitive consumption of ATP are important targets that can block excessive HSP generation. We developed a magnetic nanocatalytic system comprised of glucose oxidase (GOD)-loaded hollow iron oxide nanocatalysts (HIONCs) to drive starvation-chemodynamic-hyperthermia synergistic therapy for tumor treatment. The Fe2+ present in HIONCs contributed to ROS generation via the Fenton reaction, relieving thermo-resistance and inducing cell apoptosis by chemodynamic action. The Fenton effect was enhanced through the conditions created by increased MHT-related temperature, GOD-mediated H2O2 accumulation, and elevated tumor microenvironment acidity. The HIONCs catalase-like activity facilitated conversion of H2O2 to oxygen, thereby replenishing the oxygen levels. We further demonstrated that locally injected HIONCs-GOD effectively inhibited tumor growth in PC3 tumor-bearing mice. This study presents a multifunctional nanocarrier system driving starvation-chemodynamic-magnetic-thermal synergistic therapy via ROS and oxygen modulation for prostate tumor treatment.As an important vegetable crop of the legume family, cowpea (Vigna unguiculata L.) is grown widely for its tender pod with good taste and nutrition. The purple cowpea pods attract more attention mainly for the eye-catching color and health-promoting ingredients. Initially, large quantities of two major anthocyanins (delphinidin 3-O-glucoside and cyanidin 3-O-glucoside) and nine kinds of flavonoids (most are quercetin-based flavonol glycosides) were separated and identified from purple cowpea pod by ultra-high performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry. To study them systematically, two representative cowpea cultivars with a drastic difference in anthocyanin accumulation were further analyzed by the integration of metabolomics and transcriptomics. A total of 56 differentially accumulated metabolites and 4142 differentially expressed genes were identified, respectively. On the basis of the comprehensive analysis of multiomic data, it was shown that VuMYB90-1, VuMYB90-2, VuMYB90-3, VuCPC, VuMYB4, and endogenous bHLH and WD40 proteins coordinately control anthocyanin and flavonoid accumulation via transcriptional regulation of structural genes in purple cowpea pod.The development of catalysts for the oxygen reduction reaction is a coveted objective of relevance to energy research. This study describes a metal-free approach to catalyzing the reduction of O2 into H2O2, based on the use of redox-active carbenium species. The most active catalysts uncovered by these studies are the bifunctional dications 1,8-bis(xanthylium)-biphenylene ([3]2+) and 4,5-bis(xanthylium)-9,9-dimethylxanthene ([4]2+) which promote the reaction when in the presence of decamethylferrocene and methanesulfonic acid. Electrochemical studies carried out with [4]2+ suggest the intermediacy of an organic peroxide that, upon protonation, converts back into the starting dication while also releasing H2O2. Kinetic studies point to the second protonation event as being rate-determining.The abundant reserve and low price of potassium resources promote K-ion batteries (KIBs) becoming a promising alternative to Li-ion batteries, while the large ionic radius of K-ions creates a formidable challenge for developing suitable electrodes. Here Ni-substituted Prussian blue analogues (PBAs) are investigated comprehensively as cathodes for KIBs. The synthesized K1.90Ni0.5Fe0.5[Fe(CN)6]0.89·0.42H2O (KNFHCF-1/2) takes advantage of the merits of high capacity from electrochemically active Fe-ions, outstanding electrochemical kinetics induced by decreased band gap and K-ion diffusion activation energy, and admirable structure stability from inert Ni-ions. Therefore, a high first capacity of 81.6 mAh·g-1 at 10 mA·g-1, an excellent rate property (53.4 mAh·g-1 at 500 mA·g-1), and a long-term lifespan over 1000 cycles with the lowest fading rate of 0.0177% per cycle at 100 mA·g-1 can be achieved for KNFHCF-1/2. The K-ion intercalation/deintercalation proceeds through a facile solid solution mechanism, allowing 1.