Classification
540 - Chemistry & allied sciences
814
660 - Chemical engineering
202
543 - Analytical chemistry
173
541 - Physical chemistry
168
547 - Organic chemistry
141
620 - Engineering & allied operations
94
546 - Inorganic chemistry
86
615 - Pharmacology & therapeutics
71
621 - Applied physics
71
363 - Other social problems & services
53
610 - Medicine & health
42
519 - Probabilities & applied mathematics
35
572 - Biochemistry
34
530 - Physics
33
577 - Ecology
31
670 - Manufacturing
30
536 - Heat
25
570 - Life sciences; biology
21
333 - Economics of land & energy
20
641 - Food & drink
17
664 - Food technology
17
677 - Textiles
17
628 - Sanitary & municipal engineering
15
629 - Other branches of engineering
15
551 - Geology, hydrology & meteorology
14
571 - Physiology & related subjects
11
631 - Techniques, equipment & materials
11
004 - Data processing & computer science
10
549 - Mineralogy
10
510 - Mathematics
9
539 - Modern physics
9
550 - Earth sciences
9
658 - General management
9
616 - Diseases
8
304 - Factors affecting social behavior
7
518 - Numerical analysis
7
910 - Geography & travel
7
500 - Natural sciences & mathematics
6
531 - Classical mechanics; solid mechanics
5
580 - Plants (Botany)
5
624 - Civil engineering
5
650 - Management & auxiliary services
5
003 - Systems
4
005 - Computer programming, programs & data
4
006 - Special computer methods
4
512 - Algebra
4
612 - Human physiology
4
690 - Buildings
4
900 - History & geography
4
300 - Social sciences
3
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