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ABSTRACT Probabilistic emission inventories were developed for 1,3-butadiene, mercury (Hg), arsenic (As), benzene, formaldehyde, and lead for Jacksonville, FL. To quantify inter-unit variability in empirical emission factor data, the Maximum [...]

Small titanium-aluminum oxide clusters, TiAlOy- (y=1-3) and TiAl2Oy- (y=2-3), were studied by using anion photoelectron spectroscopy. The adiabatic detachment energies of TiAlOy- (y=1-3) were estimated to be 1.11±0.05, 1.70±0.08, and 2.47±0.08 eV based on their photoelectron spectra; those of TiAl2O2- and TiAl2O3- were estimated to be 1.17±0.08 and 2.2±0.1 eV, respectively. The structures of these clusters were determined by comparison of density functional calculations with the experimental results. The structure of TiAlO- is nearly linear with the O atom in the middle. That of TiAlO2- is a kite-shaped structure. TiAlO3- has a kite-shaped TiAlO2 unit with the third O atom attaching to the Ti atom. TiAl2O2- has two nearly degenerate Al-O-Ti-O-Al chain structures that can be considered as cis and trans forms. TiAl2O3- has two low-lying isomers, kite structure and book structure. The structures of these clusters indicate that the Ti atom tends to bind to more O atoms. [ABSTRACT FROM AUTHOR]

• Metabolomics and lipidomics were employed to analysis raw milk quality of cows. • Subclinical ketosis affected the profiles of metabolites and lipid species. • Subclinical ketosis cows had lower percentage of PUFA and CLA than healthy cows. • Fifteen volatiles were identified to be correlated with the health status of cows. • The nutritional quality of milk of subclinical ketosis cows were reduced. The metabolic status of dairy cows directly influences the nutritional quality and flavor of raw milk. A comprehensive comparison of non-volatile metabolites and volatile compounds in raw milk from healthy and subclinical ketosis (SCK) cows was performed using LC–MS, GC-FID, and HS-SPME/GC–MS. SCK can significantly alter the profiles of water-soluble non-volatile metabolites, lipids, and volatile compounds of raw milk. Compared with healthy cows, milk from SCK cows had higher contents of tyrosine, leucine, isoleucine, galactose-1-phosphate, carnitine, citrate, phosphatidylethanolamine species, acetone, 2-butanone, hexanal, dimethyl disulfide and lower content of creatinine, taurine, choline, α-ketoglutaric acid, fumarate, triglyceride species, ethyl butanoate, ethyl acetate, and heptanal. The percentage of polyunsaturated fatty acids in milk was lowered in SCK cows. Our results suggest that SCK can change milk metabolite profiles, disrupt the lipid composition of milk fat globule membrane, decrease the nutritional value, and increase the volatile compounds associated with off-flavors in milk. [ABSTRACT FROM AUTHOR]

Polyimide (PI) has garnered increasing attention in the field of membrane technology owing to its excellent comprehensive performance. In this work, PI nanofibrous membranes with a controllable pore structure were fabricated by the thermal imidization of electrospun polyamide acid (PAA) nanofibrous membranes. Polytetrafluoroethylene (PTFE) and poly(tetrafluoroethylene-hexafluoropropylene) (FEP) particles were introduced into the PAA nanofibrous membrane with the aim of enhancing the membrane's hydrophobicity and regulating its pore structure by electrospraying the PTFE/FEP mixed aqueous dispersion. During the thermal imidization process, melt casting of FEP particles occurred, leading to the adhesion of PI nanofibrous membranes and subsequent regulation of the membrane's pore structure. Meanwhile, due to the imidization temperature being lower than PTFE's melting temperature, the unmelted PTFE particles would further enhance the membrane's hydrophobicity. We have successfully provided a novel method for fabricating PI nanofibrous membranes with controllable pore structures and excellent hydrophobicity to expand their applications in membrane separation. Owing to the hydrophobicity and lipophilicity, the obtained PI nanofibrous membranes were applied to oil-water (kerosene/water) separation to characterize the separation performance. The results showed that, following the regulation of the pore structure, the PI nanofibrous membranes exhibited a high oil flux (203.83 L/m2·h) and separation efficiency (＞99.00%) without external pressure. [Display omitted] • The PI nanofibrous membrane's pore structure was regulated using electrospraying coupled with electrospinning technology. • PTFE was introduced as the dispersed-phase to inhibit the continuous-phase FEP, further regulating the membrane's structure. • The prepared PI nanofibrous membrane exhibited excellent oil-water separation performance. [ABSTRACT FROM AUTHOR]