Hydrogenation carbon-nitrogen

TNT is a compound of carbon, nitrogen, hydrogen, and oxygen. Carbon occurs in two... 

Life anywhere in this universe will be identical to the life forms we are familiar with, i.e., carbon-, nitrogen-, hydrogen-, oxygen- based and will use the same genetic code. 

Upon confronting the asymmetric carbon-nitrogen hydrogenation problem, we noted that, like a-enamides, A-acylhydrazones 32 possess an amide-like carbonyl oxygen that is similarly situated three atoms from the double bond to be reduced, and which could allow for chelation of the substrate to the catalytic Rh center. 

In an attempt to find a universal solution, it has been suggested that the internal standard should be a chemical element contained in the compounds subjected to analysis, such as carbon, nitrogen, hydrogen or chlorine [164]. The mass of the compound and,... 

Commonly analyzed stable isotopes include oxygen, carbon, nitrogen, hydrogen, and sulfur. These isotope systems have been used in research for many years because they are relatively simple to measure. Recent advances in mass spectrometry now enable the measurement of heavier stable isotopes, such as iron, copper, zinc, and molybdenum. 

Compound-specific isotope analysis Determination of the isotopic ratio of the carbon, nitrogen, hydrogen, sulfur, or oxygen contents of a single compound. The isolation of the single compound is usually achieved by some form of either off-line or on-line preparation in which gas chromatography is an important step. 

Fraser et al. [80] discuss the importance of sample preservation with respect to stable isotope analysis. The authors provide a summary of a study conducted into the effects of storage (i.e., in different packaging materials over time) on the carbon, nitrogen, hydrogen, and oxygen isotope values of human hair and nail samples. 

All organisms are comprised of myriad organic compounds, and the human body is no exception. Among other elements, our bodies contain carbon, nitrogen, hydrogen, and phosphorus in molecules such as nucleic acids, proteins, fats, and carbohydrates, and... 

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