Classification
541 - Physical chemistry
331
620 - Engineering & allied operations
153
530 - Physics
120
543 - Analytical chemistry
60
547 - Organic chemistry
58
621 - Applied physics
56
546 - Inorganic chemistry
42
539 - Modern physics
41
660 - Chemical engineering
28
536 - Heat
26
571 - Physiology & related subjects
23
610 - Medicine & health
16
551 - Geology, hydrology & meteorology
10
664 - Food technology
10
537 - Electricity & electronics
8
641 - Food & drink
7
540 - Chemistry & allied sciences
6
572 - Biochemistry
6
363 - Other social problems & services
5
535 - Light & infrared & ultraviolet phenomena
5
615 - Pharmacology & therapeutics
5
616 - Diseases
5
500 - Natural sciences & mathematics
4
542 - Techniques, equipment & materials
4
570 - Life sciences; biology
4
629 - Other branches of engineering
3
006 - Special computer methods
2
518 - Numerical analysis
2
519 - Probabilities & applied mathematics
2
520 - Astronomy & allied sciences
2
531 - Classical mechanics; solid mechanics
2
548 - Crystallography
2
549 - Mineralogy
2
624 - Civil engineering
2
333 - Economics of land & energy
1
370 - Education
1
501 - Philosophy & theory
1
509 - Historical, geographic & persons treatment
1
510 - Mathematics
1
511 - General principles of mathematics
1
523 - Specific celestial bodies & phenomena
1
538 - Magnetism
1
550 - Earth sciences
1
553 - Economic geology
1
613 - Personal health & safety
1
614 - Incidence & prevention of disease
1
628 - Sanitary & municipal engineering
1
667 - Cleaning, color & coating technologies
1