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1.
Environ Sci Technol ; 55(9): 6214-6226, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33822592

RESUMEN

As reliance on wind and solar power for electricity generation increases, so does the importance of understanding how variability in these resources affects the feasible, cost-effective ways of supplying energy services. We use hourly weather data over multiple decades and historical electricity demand data to analyze the gaps between wind and solar supply and electricity demand for California (CA) and the Western Interconnect (WECC). We quantify the occurrence of resource droughts when the daily power from each resource was less than half of the 39-year daily mean for that day of the year. Averaged over 39 years, CA experienced 6.6 days of solar and 48 days of wind drought per year, compared to 0.41 and 19 for WECC. Using a macro-scale electricity model, we evaluate the potential for both long-term storage and more geographically diverse generation resources to minimize system costs. For wind-solar-battery electricity systems, meeting California demand with WECC generation resources reduces the cost by 9% compared to constraining resources entirely to California. Adding long-duration storage lowers system costs by 21% when treating California as an island. This data-driven analysis quantifies rare weather-related events and provides an understanding that can be used to inform stakeholders in future electricity systems.


Asunto(s)
Energía Solar , Viento , California , Sequías , Electricidad , Energía Renovable
2.
J Phys Chem A ; 120(32): 6444-50, 2016 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-27445084

RESUMEN

Recent studies have shown that sea spray aerosol (SSA) has a size-dependent, complex composition consisting of biomolecules and biologically derived organic compounds in addition to salts. This additional chemical complexity most likely influences the heterogeneous reactivity of SSA, as these other components will have different reactive sites and reaction pathways. In this study, we focus on the reactivity of a class of particles derived from some of the biological components of sea spray aerosol including lipopolysaccharides (LPS) that undergo heterogeneous chemistry within the reactive sites of the biological molecule. Examples of these reactions and the relevant reactive sites are proposed as follows: R-COONa(s) + HNO3(g) → NaNO3 + R-COOH and R-HPO4Na(s) + HNO3(g) → NaNO3 + R-H2PO4. These reactions may be a heterogeneous pathway not only for sea spray aerosol but also for a variety of other types of atmospheric aerosol as well.


Asunto(s)
Lipopolisacáridos/química , Ácido Nítrico/química , Aerosoles/química , Gases/química , Agua de Mar/química
3.
Cancer ; 121(1): 102-12, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25155924

RESUMEN

BACKGROUND: Time trends in cancer incidence rates (IR) are important to measure the changing burden of cancer on a population over time. The overall IR of cancer in the United States is declining. Although central nervous system tumors (CNST) are rare, they contribute disproportionately to mortality and morbidity. In this analysis, the authors examined trends in the incidence of the most common cancers and CNST between 2000 and 2010. METHODS: The current analysis used data from the United States Cancer Statistics publication and the Central Brain Tumor Registry of the United States. Age-adjusted IR per 100,000 population with 95% confidence intervals and the annual percent change (APC) with 95% confidence intervals were calculated for selected common cancers and CNST overall and by age, sex, race/ethnicity, selected histologies, and malignancy status. RESULTS: In adults, there were significant decreases in colon (2000-2010: APC, -3.1), breast (2000-2010: APC, -0.8), lung (2000-2010: APC, -1.1), and prostate (2000-2010: APC, -2.4) cancer as well as malignant CNST (2008-2010: APC, -3.1), but a significant increase was noted in nonmalignant CNST (2004-2010: APC, 2.7). In adolescents, there were significant increases in malignant CNST (2000-2008: APC, 1.0) and nonmalignant CNST (2004-2010: APC, 3.9). In children, there were significant increases in acute lymphocytic leukemia (2000-2010: APC, 1.0), non-Hodgkin lymphoma (2000-2010: APC, 0.6), and malignant CNST (2000-2010: APC, 0.6). CONCLUSIONS: Surveillance of IR trends is an important way to measure the changing public health and economic burden of cancer. In the current study, there were significant decreases noted in the incidence of adult cancer, whereas adolescent and childhood cancer IR were either stable or increasing.


Asunto(s)
Neoplasias del Sistema Nervioso Central/epidemiología , Neoplasias/epidemiología , Adolescente , Adulto , Anciano , Neoplasias del Sistema Nervioso Central/etnología , Niño , Preescolar , Análisis por Conglomerados , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/etnología , Programa de VERF , Factores de Tiempo , Estados Unidos/epidemiología , Estados Unidos/etnología , Adulto Joven
4.
ACS Appl Energy Mater ; 7(10): 4288-4293, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38817848

RESUMEN

Manganese antimonate (MnySb1-yOx) electrocatalysts for the oxygen-evolution reaction (OER) were synthesized via chemical vapor deposition. Mn-rich rutile Mn0.63Sb0.37Ox catalysts on fluorine-doped tin oxide (FTO) supports drove the OER for 168 h (7 days) at 10 mA cm-2 with a time-averaged overpotential of 687 ± 9 mV and with >97% Faradaic efficiency. Time-dependent anolyte composition analysis revealed the steady dissolution of Mn and Sb. Extended durability analysis confirmed that Mn-rich MnySb1-yOx materials are more active but dissolve at a faster rate than previously reported Sb-rich MnySb1-yOx alloys.

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