Comprehensive Profiling by Non-targeted Stable Isotope Tracing Capillary Electrophoresis-Mass Spectrometry: A New Tool Complementing Metabolomic Analyses of Polar Metabolites

Mass spectrometry (MS) driven metabolomics is a frequently used tool in various areas of life sciences; however, the analysis of polar metabolites is less commonly included. In general, metabolomic analyses lead to the detection of the total amount of all covered metabolites. This is currently a major limitation with respect to metabolites showing high turnover rates, but no changes in their concentration. Such metabolites and pathways could be crucial metabolic nodes (e.g., potential drug targets in cancer metabolism). A stable-isotope tracing capillary electrophoresis-mass spectrometry (CE-MS) metabolomic approach was developed to cover both polar metabolites and isotopologues in a non-targeted way. An in-house developed software enables high throughput processing of complex multidimensional data. The practicability is demonstrated analyzing [U-C-13]-glucose exposed prostate cancer and non-cancer cells. This CE-MS-driven analytical strategy complements polar metabolite profiles through isotopologue labeling patterns, thereby improving not only the metabolomic coverage, but also the understanding of metabolism

Preparation of Axially Chiral 2,2 '-Biimidazole Ligands through Remote Chirality Delivery and Their Application in Asymmetric Carbene Insertion into N-H of Carbazoles

Axially chiral biimidazole ligands have been rarely synthesized and studied, in contrast to the significant achievements in the synthesis and application of central chiral imidazole ligands. Herein, a series of novel axially chiral 2,2'-biimidazole ligands were synthesized from the reaction of 2,2'-bis(bromomethyl)-1,1'-binaphthalene and 2,2'-biimidazole in one step through the strategy of remote chirality delivery. These ligands have been proven to be efficient for Cu- or Fe-catalyzed asymmetric insertion of alpha-aryl-alpha-diazoacetates into the N-H bond of carbazoles with up to 96% ee

Multicore-Shell Bi@N-doped Carbon Nanospheres for High Power Density and Long Cycle Life Sodium- and Potassium-Ion Anodes

Bismuth (Bi) is an attractive material as anodes for both sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs), because it has a high theoretical gravimetric capacity (386 mAh g(-1)) and high volumetric capacity (3800 mAh L-1). The main challenges associated with Bi anodes are structural degradation and instability of the solid electrolyte interphase (SEI) resulting from the huge volume change during charge/discharge. Here, a multicore-shell structured Bi@N-doped carbon (Bi@N-C) anode is designed that addresses these issues. The nanosized Bi spheres are encapsulated by a conductive porous N-doped carbon shell that not only prevents the volume expansion during charge/discharge but also constructs a stable SEI during cycling. The Bi@N-C exhibits unprecedented rate capability and long cycle life for both NIBs (235 mAh g(-1) after 2000 cycles at 10 A g(-1)) and KIBs (152 mAh g(-1) at 100 A g(-1)). The kinetic analysis reveals the outstanding electrochemical performance can be attributed to significant pseudocapacitance behavior upon cycling

Numerical analysis of thermal radiation noise of shock layer over an infrared optical dome at near-ground altitudes

To examine the effect of atmospheric trace species on the infrared thermal radiation of a supersonic dome, a series of radiation characteristics with different geometry sizes at near-ground altitudes were investigated numerically. The conjugate heat transfer method was applied to build the heat transfer model of the optical dome. Three major radiating species of H2O, CO2, and CO were taken into account in the shock layer. A line-by-line (LBL) method was used for evaluating the radiative properties of species. A line-of-sight (LOS) approach was applied to solve the radiative transfer equation (RTE). The simulated and measured results of the dome were also proposed to validate the numerical method. The effects of the dome geometry size, the dome material and the time-varying altitude on the infrared radiation noise were studied in detail. The results show that the altitude varying radiation intensity along the LOS is related to the ambient density and velocity. The variation of the dome radius is proportional to the total radiation received on the dome surface. It is observed that the maximum radiation intensity along the LOS does not occur in the normal direction of the receiving point, but it is determined by both the flow field parameters and the path length. Also, the radiation increment corresponding to different dome sizes approximately obeys a Gaussian distribution related to the product of density and velocity