TP Chemical technology 156 TA Engineering (General). Civil engineering (General) 147 Mixtures 94 QD Chemistry 68 Technology: general issues 65 human 61 TJ Mechanical engineering and machinery 60 History of engineering and technology 54 Humans 52 Research & information: general 46 Article 41 T Technology (General) 37 article 30 controlled study 29 female 26 male 26 Concrete mixtures 24 Asphalt mixtures 23 Q Science (General) 23 Biology, life sciences 21 TK Electrical engineering. Electronics Nuclear engineering 21 nonhuman 21 Female 20 adult 20 chemistry 20 Compressive strength 18 Male 17 QC Physics 17 procedures 17 Research and information: general 16