2,6-Bis(3-fluoro­phen­yl)-3-isopropyl­piperidin-4-one

In the title compound, C20H21F2NO, the piperidine ring in each of the two independent mol­ecules in the asymmetric unit adopts a normal chair conformation with an equatorial orientation of the 3-fluoro­phenyl groups. The dihedral angles between the two 3-fluoro­phenyl rings are 49.89 (7) and 50.35 (7)° in the two mol­ecules

Ethyl 4-[2-(3,5-dimethyl-4-oxo-2,6-diphenyl­piperidin-1-yl)-2-oxoeth­yl]piperazine-1-carboxyl­ate

In the title compound, C28H35N3O4, the piperidine ring adopts a boat conformation while the piperazine ring adopts a chair conformation with an equatorial orientation of the phenyl groups. The dihedral angle between the mean planes of the benzene rings is 74.14 (8)°. The mol­ecular conformation is stabilized by a weak intra­molecular C—H⋯N inter­action and the crystal packing is stabilized by weak inter­molecular C—H⋯O inter­actions

1-Chloro­acetyl-2,6-bis­(2-chloro­phen­yl)-3,5-dimethyl­piperidin-4-one

In the title compound, C21H20Cl3NO2, the piperidin-4-one ring adopts a boat conformation. The two 2-chloro­phenyl groups are approximately perpendicular to each other, making a dihedral angle of 74.07 (8)°

Microscopic observation of a liquid-liquid-(semi)solid phase in polluted PM2.5

Atmospheric aerosol particles are complex mixtures having various physicochemical properties. To predict the role and characteristics of such complex aerosol particles in air pollution and related atmospheric chemistry, our knowledge of the number and types of phases in complex aerosol particles should be improved. However, most studies on the phase behavior of aerosol particles have been conducted in the laboratory and have not used real-world aerosol particles. In this study, using a combination of optical microscopy and poke-and-flow technique, we investigated the number and types of phases of actual aerosol particles of particulate matter < 2.5 µm (PM2.5) collected on heavily polluted days in Seosan, South Korea in winter 2020–2021. From the microscopic observations at 293 K, it showed that the PM2.5 particles exist in a single liquid phase at relative humidity (RH) >∼85%, a liquid-liquid phase at ∼70% < RH <∼85%, a liquid-liquid-(semi)solid phase at ∼30% < RH <∼70%, and a (semi)solid phase at RH <∼30% upon dehydration. This reveals that three phases of atmospheric aerosol particles coexisting as liquid-liquid and liquid-liquid-(semi)solid would be the most common phases in the atmosphere considering ambient RH ranges. These observations provide fundamental properties necessary for improved predictions of air quality and aerosol chemistry such as reactive uptake of N2O5, size distributions, and mass concentrations of aerosol particles

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio