Sulfur trioxide (SO) is one of the most active chemical species in the atmosphere, and its atmospheric fate has profound implications to air quality and human health. The dominant gas-phase loss pathway for SO is generally believed to be the reaction with water molecules, resulting in sulfuric acid. The latter is viewed as a critical component in the new particle formation (NPF). Herein, a new and competitive loss pathway for SO in the presence of abundant gas-phase ammonia (NH) species is identified. Specifically, the reaction between SO and NH, which produces sulfamic acid, can be self-catalyzed by the reactant (NH). In dry and heavily polluted areas with relatively high concentrations of NH, the effective rate constant for the bimolecular SO-NH reaction can be sufficiently fast through this new loss pathway for SO to become competitive with the conventional loss pathway for SO with water. Furthermore, this study shows that the final product of the reaction, namely, sulfamic acid, can enhance the fastest possible rate of NPF from sulfuric acid and dimethylamine (DMA) by about a factor of 2. An alternative source of stabilizer for acid-base clustering in the atmosphere is suggested, and this new mechanism for NPF has potential to improve atmospheric modeling in highly polluted regions.

Lipoprotein glomerulopathy is a rare inherited renal disease, caused by mutation of the APOE gene, characterized by proteinuria and nephrotic syndrome with elevated serum apoE. Since its treatment and outcome are unknown, we retrospectively studied 35 patients within 31 unrelated Han families with biopsy-proven lipoprotein glomerulopathy residing in the same county in southwest China. DNA sequencing detected the APOE Kyoto mutation (p. Arg25Cys) in all patients and 28 asymptomatic relatives. All shared the same ɛ3 allele. The patients presented with proteinuria, higher total triglyceride, and serum apoE levels relative to non-carriers. The serum apoE and triglyceride levels of asymptomatic carriers were between those of the patients and non-carriers. Sixteen patients received fenofibrate treatment for over 12 months. Six reached complete remission (proteinuria under 0.3 g/day with stable serum creatinine) with intensive control of their lipid profile (normalized serum apoE and triglycerides under 100 mg/dl). Eight reached partial remission. At 3 years of follow-up, patients treated with fenofibrate had superior survival and stable renal function. Thus, fenofibrate can induce lipoprotein glomerulopathy remission and the fibrate effects depend on the degree of lipid control and baseline proteinuria. Moreover, normalization of serum apoE and triglycerides can be used to judge the efficacy of lipid-lowering treatment.

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Conversion of N=N=CHSiMe3 to O=C=CHSiMe3 by the radical complexes .Cr(CO)3C5R5 (R = H, CH3) derived from dissociation of [Cr(CO)3(C5R5)]2 have been investigated under CO, Ar, and N2 atmospheres. Under an Ar or N2 atmosphere the reaction is stoichiometric and produces the Cr[triple bond]Cr triply bonded complex [Cr(CO)2(C5R5)]2. Under a CO atmosphere regeneration of [Cr(CO)3(C5R5)]2 (R = H, CH3) occurs competitively and conversion of diazo to ketene occurs catalytically as well as stoichiometrically. Two key intermediates in the reaction, .Cr(CO)2(ketene)(C5R5) and Cr2(CO)5(C5R5)2 have been detected spectroscopically. The complex .Cr(13CO)2(O=13C=CHSiMe3)(C5Me5) has been studied by electron spin resonance spectroscopy in toluene solution: g(iso) = 2.007; A(53Cr) = 125 MHz; A(13CO) = 22.5 MHz; A(O=13C=CHSiMe3) = 12.0 MHz. The complex Cr2(CO)5(C5H5)2, generated in situ, does not show a signal in its 1H NMR and reacts relatively slowly with CO. It is proposed to be a ground-state triplet in keeping with predictions based on high level density functional theory (DFT) studies. Computed vibrational frequencies are also in good agreement with experimental data. The rates of CO loss from 3Cr2(CO)5(C5H5)2 producing 1[Cr(CO)2(C5H5)]2 and CO addition to 3Cr2(CO)5(C5H5)2 producing 1[Cr(CO)3(C5H5)]2 have been measured by kinetics and show DeltaH approximately equal 23 kcal mol(-1) for both processes. Enthalpies of reduction by Na/Hg under CO atmosphere of [Cr(CO)n(C5H5)]2 (n = 2,3) have been measured by solution calorimetry and provide data for estimation of the Cr[triple bond]Cr bond strength in [Cr(CO)2(C5H5)]2 as 72 kcal mol(-1). The complex [Cr(CO)2(C5H5)]2 does not readily undergo 13CO exchange at room temperature or 50 degrees C implying that 3Cr2(CO)5(C5H5)2 is not readily accessed from the thermodynamically stable complex [Cr(CO)2(C5H5)]2. A detailed mechanism for metalloradical based conversion of diazo and CO to ketene and N2 is proposed on the basis of a combination of experimental and theoretical data.

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Gas-phase simulations of nitric acid-amine chemistry suggest that the fundamental acid-base interaction between HNO and NH results in a variety of HNO-NH-based complexes, such as (HNO)·(NH), (HNO)·(NH), and (HNO)·(NH), that can be formed. The formation of these complexes in the gas phase follow different growth mechanisms under different relative humidity conditions. On the other hand, at the air-water interface, Born-Oppenheimer molecular dynamics simulations suggest that the formation of the fundamental NO··(R)(R)NH [for NH, R = R = H; CHNH, R = H, R = CH; and (CH)NH, R = R = CH] ion pairs require the formation of the HNO··(R)(R)NH complexes in the gas-phase prior to their adsorption on the water surface. Ion-pair formation at the water surface involves proton transfer from HNO to (R)(R)NH and occurs within a few femtoseconds of the simulation. The NO··(R)(R)NH ion pairs preferentially remain at the interface over the picosecond time scale, where they are stabilized via hydrogen bonding with surface water molecules. This offers a novel chemical framework for understanding gas-to-particle partitioning in the atmosphere. These results not only improve our understanding of the formation of nitrate particulates in polluted urban environments, but also provide useful guidelines for understanding particle formation in forested or coastal environments, in which organic acids and organosulfates are present in significant quantities and their exact role in particle formation remains elusive.

Graphite is useful as a low-cost and high-voltage cathode of dual-ion batteries (DIBs) to allow anion (de-)­intercalation, yet its practical applications are hindered by low Coulombic efficiencies (CEs) and poor cyclability. Meanwhile, the solvation behavior of anions and the impact of solvation on interphase chemistry have not been well clarified. Herein, a fluorinated co-solvent-modified electrolyte is proposed for graphite cathodes in sodium-based DIBs. The introduced composition participates in the solvation of Na+ cations and PF6 ̅ anions. The NaF-rich interphase layer formed on the anodes effectively inhibits side reactions with the electrolyte. More importantly, the fluorinated cathode–electrolyte interphase plays significant roles in suppressing electrolyte oxidation decomposition and maintaining the structural integrity of graphite. Consequently, this modified electrolyte endows graphite cathodes with enhanced CEs and long cycle life, and it enables good cycling stability of graphite cathode-based full cells. With this full understanding of anion solvation, this work provides a guideline to design electrolytes for anion-intercalation cathodes.

Despite the high abundance in the atmosphere, alcohols in general and methanol in particular are believed to play a small role in atmospheric new particle formation (NPF) largely due to the weak binding abilities of alcohols with the major nucleation precursors, e.g., sulfuric acid (SA) and dimethylamine (DMA). Herein, we identify a catalytic reaction that was previously overlooked, namely, the reaction between methanol and SO3, catalyzed by SA, DMA, or water. We found that alcohols can have unexpected quenching effects on the NPF process, particularly in dry and highly polluted regions with high concentrations of alcohols. Specifically, the catalytic reaction between methanol and SO3 can convert methanol into a less-volatile species––methyl hydrogen sulfate (MHS). The latter was initially thought to be a good nucleation agent for NPF. However, our simulation results suggest that the formation of MHS consumes an appreciable amount of atmospheric SO3, disfavoring further reactions of SO3 with H2O. Indeed, we found that MHS formation can cause a reduction of SA concentration up to 87%, whereas the nucleation ability of MHS toward new particles is not as good as that of SA. Hence, a high abundance of methanol in the atmosphere can lower the particle nucleation rate by as much as two orders of magnitude. Such a quenching effect suggests that the recently identified catalytic reactions between alcohols and SO3 need to be considered in atmospheric modeling in order to predict SA concentration from SO2, while also account for their potentially negative effect on NPF.