Classification
660 - Chemical engineering
63
668 - Technology of other organic products
47
547 - Organic chemistry
37
664 - Food technology
34
628 - Sanitary & municipal engineering
31
615 - Pharmacology & therapeutics
29
620 - Engineering & allied operations
28
632 - Plant injuries, diseases & pests
26
541 - Physical chemistry
18
363 - Other social problems & services
16
662 - Explosives, fuels & related products
15
621 - Applied physics
14
661 - Industrial chemicals
13
543 - Analytical chemistry
9
338 - Production
7
540 - Chemistry & allied sciences
7
572 - Biochemistry
7
665 - Industrial oils, fats, waxes & gases
7
610 - Medicine & health
6
631 - Techniques, equipment & materials
6
546 - Inorganic chemistry
5
574 - [Unassigned]
5
612 - Human physiology
5
663 - Beverage technology
5
676 - Pulp & paper technology
5
677 - Textiles
5
674 - Lumber processing, wood products & cork
4
681 - Precision instruments & other devices
4
542 - Techniques, equipment & materials
3
553 - Economic geology
3
346 - Private law
2
530 - Physics
2
537 - Electricity & electronics
2
581 - Specific topics in natural history
2
613 - Personal health & safety
2
614 - Incidence & prevention of disease
2
616 - Diseases
2
623 - Military & nautical engineering
2
629 - Other branches of engineering
2
630 - Agriculture & related technologies
2
667 - Cleaning, color & coating technologies
2
678 - Elastomers & elastomer products
2
306 - Culture & institutions
1
344 - Labor, social, education & cultural law
1
507 - Education, research & related topics
1
522 - Techniques, equipment & materials
1
538 - Magnetism
1
549 - Mineralogy
1
571 - Physiology & related subjects
1
577 - Ecology
1
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