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Author Question: How many carbon signals are expected in the proton-decoupled 13C NMR spectrum of the compound shown below? (Read 85 times) |
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.
Ether was used widely for surgeries but became less popular because of its flammability and its tendency to cause vomiting. In England, it was quickly replaced by chloroform, but this agent caused many deaths and lost popularity.