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In this paper, we ask whether rapidly displacing coal electricity generation with underutilized, existing natural gas capacity has net societal benefits or net costs when considering climate change, economics, and air pollution. We use a power plant dispatch model to quantify the effects of dispatching because of a tax on carbon or because of a tax on carbon, methane leakage, and air pollution. We explicitly model exhaust stack CO2 emissions, production costs, health damages caused by criteria air pollutants, and methane leakage from the natural gas infrastructure. We show that (1) the optimal coal-to-gas redispatch displaces 62-77% of coal energy, leaving some coal online, (2) the health benefits of redispatch are larger in magnitude than the climate benefits, (3) reducing methane leakage rates from 2.3 to 2.0% increases the net climate benefits of redispatch by $1.1B-$1.4B, (4) although internalizing methane leakage, climate damages, and health damages in the power plant dispatch maximizes the net benefits of redispatch, 75-87% of these benefits can be achieved using a carbon tax mechanism alone, and (5) when choosing an optimal carbon tax, focusing on climate at the exclusion of health-and vice-versa-provides less net benefit than looking at both issues jointly.Mass spectrometry imaging (MSI) is a powerful technique for the label-free spatially resolved analysis of biological tissues. Coupling ion mobility (IM) separation with MSI allows for separation of isobars in the mobility dimension and increases confidence of peak assignments. Recently, imaging experiments have been implemented on several commercially available and custom-designed ion mobility instruments, making IM-MSI experiments more broadly accessible to the MS community. However, the absence of open access data analysis software for IM-MSI systems presents a bottleneck. Herein, we present an imaging workflow to visualize IM-MSI data produced on the Agilent 6560 ion mobility quadrupole time-of-flight system. Specifically, we have developed a Python script, the ion mobility-mass spectrometry image creation script (IM-MSIC), which interfaces Agilent's Mass Hunter Mass Profiler software with the MacCoss lab's Skyline software and generates drift time and mass-to-charge-selected ion images. In the workflow, Mass Profiler is used for an untargeted feature detection. The IM-MSIC script mediates user input of data, extracts ion chronograms utilizing Skyline's command-line interface, and then proceeds toward ion image generation within a single user interface. Ion image postprocessing is subsequently performed using different tools implemented in accompanying scripts. Though the current work only showcases Agilent IM-MSI data, this workflow can be readily adapted for use with most major instrument vendors.2,5-Dimethylpyrazine (2,5-DMP) is an indispensable additive for flavoring in the food industry and an important substrate for producing hypoglycemic and antilipolytic drugs. However, 2,5-DMP is produced by chemical synthesis in industry. Herein, a "green" strategy to produce 2,5-DMP has been reported for the first time. To do this, we rewrote the de novo 2,5-DMP biosynthesis pathway and substrate transmembrane transport in an l-threonine high-yielding strain to promote highly efficient 2,5-DMP production from glucose by submerged fermentation. The final strain T6-47-7 could produce 1.43 ± 0.07 g/L of 2,5-DMP with a carbon yield of 6.78% and productivity of 0.715 g/(L·d) in shake-flask fermentation using a phase-wise manner of hypoxia-inducible expression. The design-based strategy for constructing the 2,5-DMP high-yielding strain reported here could serve as a general concept for breeding high-yielding strains that produce some other type of alkylpyrazine.Effective permeation into, and diffusive mass transport within, solvent-filled metal-organic frameworks (MOFs) is critical in applications such as MOF-based chemical catalysis of condensed-phase reactions. In this work, we studied the entry from solution of a luminescent probe molecule, 1,3,5,7-tetramethyl-4,4-difluoroboradiazaindacene (BODIPY), into the 1D channel-type, zirconium-based MOF NU-1008 and subsequent transport of the probe through the MOF. Measurements were accomplished via in situ confocal fluorescence microscopy of individual crystallites, where the evolution of the fluorescence response from the crystallite was followed as functions of both time and location within the crystallite. From the confocal data, intracrystalline transport of BODIPY is well-described by one-dimensional diffusion along the channel direction. Varying the chemical identity of the solvent revealed an inverse dependence of probe-molecule diffusivity on bulk-solvent viscosity, qualitatively consistent with expectations from the Stokes-Einstein equation for molecular diffusion. At a more quantitative level, however, measured diffusion coefficients are about 100-fold smaller than expected from Stokes-Einstein, pointing to substantial channel-confinement effects. Evaluation of the confocal data also reveals a non-negligible mass transport resistance, i.e., surface barrier, associated with the probe molecule leaving the solution and permeating the exterior surface of the MOF. Permeation by the probe entails displacement of solvent from the MOF channels. The magnitude of the resistance increases with the size of the solvent molecule. This work draws attention to the importance of MOF structure, external-surface barriers, and solvent molecule identity to the overall transport process in MOFs, which should assist in understanding the performance of MOFs in applications such as condensed-phase heterogeneous catalysis.MoS2 is the most widely used dry lubricant for low friction applications in vacuum environments. However, due to its lamellar nature it exfoliates during sliding, leading to high wear, high coefficient of friction (COF), and low stability. Here, we report the mechanical properties and the vacuum (10-4 Pa) tribological performance of nitrogen-alloyed transition-metal-dichalcogenide (TMD-N) coatings. The coatings were deposited using a hybrid deposition method, that is, reactive direct current (DC) sputtering of MoS2 target assisted by an additional plasma source. GW2580 price The tribological tests were performed at relatively low contact stresses to replicate real industrial needs. The interaction between different mating surfaces (coating versus steel, coating versus coating) has been reported. Additionally, the effects of loads on the sliding properties were also studied for coating versus coating interactions. A maximum hardness of 8.9 GPa was measured for the 37 atom % N-alloyed coating. In all mating conditions, the pure MoS2 coating had COF in the range of 0.