Institution
Pacific Northwest National Laboratory
Facility•Richland, Washington, United States•
About: Pacific Northwest National Laboratory is a facility organization based out in Richland, Washington, United States. It is known for research contribution in the topics: Catalysis & Aerosol. The organization has 11581 authors who have published 27934 publications receiving 1120489 citations. The organization is also known as: PNL & PNNL.
Topics: Catalysis, Aerosol, Mass spectrometry, Population, Ion
Papers published on a yearly basis
Papers
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TL;DR: Determination of the thermodynamic driving force for elimination of H2 from molecular complexes is important for the rational design of molecular electrocatalysts, and allows the design of metal complexes of abundant, inexpensive metals rather than precious metals ("Cheap Metals for Noble Tasks").
228 citations
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TL;DR: A self-supporting and flexible activated carbon/carbon nanotube/reduced graphene oxide (AC/CNT/RGO) film has been rationally designed for constructing high-performance supercapacitor as mentioned in this paper.
227 citations
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TL;DR: In this paper, the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) is modified to include a volatility basis set (VBS) treatment of secondary organic aerosol formation.
Abstract: . The Weather Research and Forecasting model coupled with chemistry (WRF-Chem) is modified to include a volatility basis set (VBS) treatment of secondary organic aerosol formation. The VBS approach, coupled with SAPRC-99 gas-phase chemistry mechanism, is used to model gas-particle partitioning and multiple generations of gas-phase oxidation of organic vapors. In addition to the detailed 9-species VBS, a simplified mechanism using 2 volatility species (2-species VBS) is developed and tested for similarity to the 9-species VBS in terms of both mass and oxygen-to-carbon ratios of organic aerosols in the atmosphere. WRF-Chem results are evaluated against field measurements of organic aerosols collected during the MILAGRO 2006 campaign in the vicinity of Mexico City. The simplified 2-species mechanism reduces the computational cost by a factor of 2 as compared to 9-species VBS. Both ground site and aircraft measurements suggest that the 9-species and 2-species VBS predictions of total organic aerosol mass as well as individual organic aerosol components including primary, secondary, and biomass burning are comparable in magnitude. In addition, oxygen-to-carbon ratio predictions from both approaches agree within 25 %, providing evidence that the 2-species VBS is well suited to represent the complex evolution of organic aerosols. Model sensitivity to amount of anthropogenic semi-volatile and intermediate volatility (S/IVOC) precursor emissions is also examined by doubling the default emissions. Both the emission cases significantly under-predict primary organic aerosols in the city center and along aircraft flight transects. Secondary organic aerosols are predicted reasonably well along flight tracks surrounding the city, but are consistently over-predicted downwind of the city. Also, oxygen-to-carbon ratio predictions are significantly improved compared to prior studies by adding 15 % oxygen mass per generation of oxidation; however, all modeling cases still under-predict these ratios downwind as compared to measurements, suggesting a need to further improve chemistry parameterizations of secondary organic aerosol formation.
227 citations
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TL;DR: Results indicate that increases in flame temperature leads to higher contents of non-aromatic functionalities in nascent soot formed in the flames studied, especially towards larger distances above the burner surface.
Abstract: Previous studies suggest that soot formed in premixed flat flames can contain a substantial amount of aliphatic compounds. Presence of these compounds may affect the kinetics of soot mass growth and oxidation in a way that is currently not understood. Using an infrared spectrometer coupled to a microscope (micro-FTIR), we examined the composition of soot sampled from a set of ethylene–argon–oxygen flames recently characterized (A. D. Abid, et al. Combust. Flame, 2008, 154, 775–788), all with an equivalence ratio ϕ = 2.07 but varying in maximum flame temperatures. Soot was sampled at three distances above the burner surface using a probe sampling technique and deposited on silicon nitride thin film substrates using a cascade impactor. Spectra were taken and analyses performed for samples collected on the lowest five impactor stages with the cut-off sizes of D50 = 10, 18, 32, 56 and 100 nm. The micro-FTIR spectra revealed the presence of aliphatic C–H, aromatic C–H and various oxygenated functional groups, including carbonyl (CO), C–O–C and C–OH groups. Spectral analyses were made to examine variations of these functional groups with flame temperature, sampling position and particle size. Results indicate that increases in flame temperature leads to higher contents of non-aromatic functionalities. Functional group concentrations were found to be ordered as follows: [CO] < [C–O] < [aliphatic C–H]. Aliphatic C–H was found to exist in significant quantities, with very little oxygenated groups present. The ratio of these chemical functionalities to aromatic C–H remains constant for particle sizes spanning 10–100 nm. The results confirm a previous experimental finding: a significant amount of aliphatic compounds is present in nascent soot formed in the flames studied, especially towards larger distances above the burner surface.
227 citations
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TL;DR: In this article, the importance of including electron correlation effects in the determination of the equilibrium structure and hyperpolarizabilities of p-nitroaniline is investigated, and the second-order perturbation theory gives static hyperpolicizabilities which are 88% to 100% larger than those obtained without electron correlation.
Abstract: The importance of including electron correlation effects in the determination of the equilibrium structure and hyperpolarizabilities of p-nitroaniline is investigated. Second-order perturbation theory gives static hyperpolarizabilities which are 88% to 100% larger than those obtained without electron correlation. These values are scaled by a self-consistent field frequency-dependent contribution for comparison with experimental measurements
227 citations
Authors
Showing all 11848 results
Name | H-index | Papers | Citations |
---|---|---|---|
Yi Cui | 220 | 1015 | 199725 |
Derek R. Lovley | 168 | 582 | 95315 |
Xiaoyuan Chen | 149 | 994 | 89870 |
Richard D. Smith | 140 | 1180 | 79758 |
Taeghwan Hyeon | 139 | 563 | 75814 |
Jun Liu | 138 | 616 | 77099 |
Federico Capasso | 134 | 1189 | 76957 |
Jillian F. Banfield | 127 | 562 | 60687 |
Mary M. Horowitz | 127 | 557 | 56539 |
Frederick R. Appelbaum | 127 | 677 | 66632 |
Matthew Jones | 125 | 1161 | 96909 |
Rainer Storb | 123 | 905 | 58780 |
Zhifeng Ren | 122 | 695 | 71212 |
Wei Chen | 122 | 1946 | 89460 |
Thomas E. Mallouk | 122 | 549 | 52593 |