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Results of Hazardous and Mixed Waste Excavation from the Chemical Waste Landfill
This paper describes the results of the excavation of a 1.9-acre hazardous and mixed waste landfill operated for 23 years at Sandia National Laboratories, Albuquerque, New Mexico. Excavation of the landfill was completed in 2 1/2 years without a single serious accident or injury. Approximately 50,000 cubic yards of soil contaminated with volatile and semi-volatile organics, metals, polychlorinated biphenyl compounds, and radioactive constituents was removed. In addition, over 400 cubic yards of buried debris was removed, including bulk debris, unknown chemicals, compressed gas cylinders, thermal and chemical batteries, explosive and ordnance debris, pyrophoric materials and biohazardous waste. Removal of these wastes included negotiation of multiple regulations and guidances encompassed in the Resource Conservation and Recovery Act (RCRA), the Toxic Substances Control Act (TSCA), and risk assessment methodology. RCRA concepts that were addressed include the area of contamination, permit modification, emergency treatment provision, and listed waste designation. These regulatory decisions enabled the project to overcome logistical and programmatic needs such as increased operational area, the ability to implement process improvements while maintaining a record of decisions and approvals
Opposing forces of cardiogenic shock: left ventricular outflow obstruction, severe mitral regurgitation, and left ventricular dysfunction in Takotsubo cardiomyopathy
Abstract Rates of stress (Takotsubo) cardiomyopathy have increased during the coronavirus pandemic due to social stressors, even in patients who are not infected with the virus. At times, Takotsubo cardiomyopathy (TC) may present as cardiogenic shock. Herein, we present a case during the pandemic of shock from TC secondary to left ventricular outflow tract obstruction (LVOTO), mitral regurgitation (MR), and left ventricular (LV) dysfunction. The contrasting management strategy of LVOTO, MR, and LV failure was cause for clinical challenge, and we highlight the balance of treating these opposing forces
Effective 1,4-Asymmetric C−C/C−O Stereoinduction in Indium-Promoted Coupling Reactions of Aldehydes to Protected and Unprotected [1-(Bromomethyl)vinyl] Alkanols. The Status of Intramolecular Chelation within Functionalized Allylindium Reagents
Factors Influencing 1,4-Asymmetric Induction during Indium-Promoted Coupling of Oxygen-Substituted Allylic Bromides to Aldehydes in Aqueous Solution
RESULTS OF HAZARDOUS AND MIXED WASTE EXCAVATION FROM THE CHEMICAL WASTE LANDFILL
ABSTRACT This paper describes the results of the excavation of a 1.9-acre hazardous and mixed waste landfill operated for 23 years at Sandia National Laboratories, Albuquerque, New Mexico. Excavation of the landfill was completed in 2 ½ years without a single serious accident or injury. Approximately 50,000 cubic yards of soil contaminated with volatile and semi-volatile organics, metals, polychlorinated biphenyl compounds, and radioactive constituents was removed. In addition, over 400 cubic yards of buried debris was removed, including bulk debris, unknown chemicals, compressed gas cylinders, thermal and chemical batteries, explosive and ordnance debris, pyrophoric materials and biohazardous waste. Removal of these wastes included negotiation of multiple regulations and guidances encompassed in the Resource Conservation and Recovery Act (RCRA), the Toxic Substances Control Act (TSCA), and risk assessment methodology. RCRA concepts that were addressed include the area of contamination, permit modification, emergency treatment provision, and listed waste designation. These regulatory decisions enabled the project to overcome logistical and programmatic needs such as increased operational area, the ability to implement process improvements while maintaining a record of decisions and approvals
Factors Influencing 1,4-Asymmetric Induction during Indium-Promoted Coupling of Oxygen-Substituted Allylic Bromides to Aldehydes in Aqueous Solution
Effective 1,4-Asymmetric C−C/C−O Stereoinduction in Indium-Promoted Coupling Reactions of Aldehydes to Protected and Unprotected [1-(Bromomethyl)vinyl] Alkanols. The Status of Intramolecular Chelation within Functionalized Allylindium Reagents
Diastereo- and Enantiodifferentiation in Indium-Promoted Allylations of 2,3-Azetidinediones in Water. Definition of Long-Range Stereocontrol Elements on π-Facial Selectivity for β-Lactam Synthesis
Effective 1,4-Asymmetric C−C/C−O Stereoinduction in Indium-Promoted Coupling Reactions of Aldehydes to Protected and Unprotected [1-(Bromomethyl)vinyl] Alkanols. The Status of Intramolecular Chelation within Functionalized Allylindium Reagents
The stereochemistry of the coupling reactions of
oxygen-substituted bromides 8−10 with
isobutyraldehyde, benzaldehyde, and cyclohexanecarboxaldehyde in water is
described. The examples
involving the O-silylated derivatives 8 exhibit moderate
anti stereoselectivity. In contrast, rather
high (most often in excess of 80:20) syn diastereofacial bias is
observed when hydroxy bromides 10
are involved. Consequently, stereocontrolled 1,4-asymmetric
induction under aqueous conditions
can be realized in either direction on demand. These results are
considered to reflect the fact that
the siloxy systems enter into C−C bond formation via conventional
Felkin−Anh transition state
arrangements. The crossover observed for the unprotected analogues
is believed to be a consequence
of the preferred adoption of chelated transition states, these
interactions likely being fundamental
to aqueous organometallic chemistry
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