All industry is made up of four sectors that are a linked together like a chain: primary, secondary, tertiary and quaternary industry. Industries in the primary and secondary sectors are the ...

There are four main types of industry: primary, secondary, tertiary and quaternary. The type of industry a country specialises in changes over time. There are social, environmental and economic ...

A sector is an industry group made up of companies ... They include the primary, secondary, tertiary, and quarternary sectors, each of which has many sub-sectors. In the financial markets ...

New research presents a versatile method for the synthesis of primary, secondary, and tertiary amines containing two stereogenic centers. In a paper just published at the website of ACS Catalysis ...