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1.
Proc Natl Acad Sci U S A ; 106(47): 19770-5, 2009 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-19884500

RESUMEN

The dramatic loss of Kilimanjaro's ice cover has attracted global attention. The three remaining ice fields on the plateau and the slopes are both shrinking laterally and rapidly thinning. Summit ice cover (areal extent) decreased approximately 1% per year from 1912 to 1953 and approximately 2.5% per year from 1989 to 2007. Of the ice cover present in 1912, 85% has disappeared and 26% of that present in 2000 is now gone. From 2000 to 2007 thinning (surface lowering) at the summits of the Northern and Southern Ice Fields was approximately 1.9 and approximately 5.1 m, respectively, which based on ice thicknesses at the summit drill sites in 2000 represents a thinning of approximately 3.6% and approximately 24%, respectively. Furtwängler Glacier thinned approximately 50% at the drill site between 2000 and 2009. Ice volume changes (2000-2007) calculated for two ice fields reveal that nearly equivalent ice volumes are now being lost to thinning and lateral shrinking. The relative importance of different climatological drivers remains an area of active inquiry, yet several points bear consideration. Kilimanjaro's ice loss is contemporaneous with widespread glacier retreat in mid to low latitudes. The Northern Ice Field has persisted at least 11,700 years and survived a widespread drought approximately 4,200 years ago that lasted approximately 300 years. We present additional evidence that the combination of processes driving the current shrinking and thinning of Kilimanjaro's ice fields is unique within an 11,700-year perspective. If current climatological conditions are sustained, the ice fields atop Kilimanjaro and on its flanks will likely disappear within several decades.


Asunto(s)
Altitud , Clima , Efecto Invernadero , Cubierta de Hielo , África , Monitoreo del Ambiente , Comunicaciones por Satélite
2.
J Anal Toxicol ; 4(2): 54-7, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7421134

RESUMEN

A death attributed to quinidine-propranolol intoxication is described. Toxicological analysis of the tissues utilized thin layer (TLC) and gas-liquid (GLC) chromatography, ultraviolet (UV) spectrophotometry and gas chromatography-mass spectrometry (GC-MS). Tissue levels for both drugs, along with their chemical ionization mass spectra, are presented.


Asunto(s)
Propranolol/envenenamiento , Quinidina/envenenamiento , Adulto , Química Encefálica , Cromatografía de Gases , Cromatografía en Capa Delgada , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Riñón/análisis , Hígado/análisis , Propranolol/análisis , Quinidina/análisis , Espectrofotometría Ultravioleta , Estómago/análisis
5.
Artículo en Inglés | MEDLINE | ID: mdl-11460320

RESUMEN

The use of bio-derived materials both as fuels and/or as blending stocks becomes more attractive as the price of middle distillate fuels, especially home heating oil, continues to rise. Historically, many biomass and agricultural derived materials have been suggested. One of the most difficult problems encountered with home heating oil is that of storage stability. High maintenance costs associated with home heating oil are, in large part, because of this stability problem. In the present research, Soygold, a soybean derived fuel, was added in concentrations of 10%-20% to both a stable middle distillate fuel and an unstable home heating oil. Fuel instability in this article will be further related to the organo-nitrogen compounds present. The soy-fuel mixtures proved stable, and the addition of the soy liquid enhanced both the combustion properties, and dramatically improved the stability of the unstable home heating oil.


Asunto(s)
Aceites Combustibles , Glycine max/química , Extractos Vegetales/química , Ésteres/química , Vivienda , Incineración , Temperatura
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