Classification
530 - Physics
1,302
620 - Engineering & allied operations
609
621 - Applied physics
242
541 - Physical chemistry
117
539 - Modern physics
91
543 - Analytical chemistry
53
660 - Chemical engineering
51
537 - Electricity & electronics
49
546 - Inorganic chemistry
49
531 - Classical mechanics; solid mechanics
33
571 - Physiology & related subjects
33
536 - Heat
32
538 - Magnetism
29
535 - Light & infrared & ultraviolet phenomena
19
519 - Probabilities & applied mathematics
18
548 - Crystallography
14
547 - Organic chemistry
13
500 - Natural sciences & mathematics
12
515 - Analysis
11
700 - The arts; fine & decorative arts
10
540 - Chemistry & allied sciences
9
670 - Manufacturing
9
523 - Specific celestial bodies & phenomena
8
003 - Systems
7
610 - Medicine & health
7
333 - Economics of land & energy
6
000 - Computer science, information & general works
5
520 - Astronomy & allied sciences
5
549 - Mineralogy
5
624 - Civil engineering
5
001 - Knowledge
4
300 - Social sciences
4
534 - Sound & related vibrations
4
551 - Geology, hydrology & meteorology
4
572 - Biochemistry
4
667 - Cleaning, color & coating technologies
4
006 - Special computer methods
3
509 - Historical, geographic & persons treatment
3
510 - Mathematics
3
616 - Diseases
3
629 - Other branches of engineering
3
791 - Public performances
3
340 - Law
2
363 - Other social problems & services
2
501 - Philosophy & theory
2
516 - Geometry
2
518 - Numerical analysis
2
532 - Fluid mechanics; liquid mechanics
2
550 - Earth sciences
2
570 - Life sciences; biology
2
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