- 
						769. 
					
						
Petroleum industry and trade
Subjects
Energy industries
 - 
						770. 
					
						
Petroleum pipelines
Subjects
Pipe
 - 
						771. 
					
						
Petroleum prospecting
Subjects
Petroleum engineeringProspecting
 - 
						772. 
					
						
Petroleum refineries
Subjects
Petroleum refining
 - 
						773. 
					
						
Pharmaceutical technology
Subjects
 - 
						774. 
					
						
Phase-locked loops
Subjects
Electric oscillators
 - 
						775. 
					
						
Philosophy of technology
Subjects
 - 
						776. 
					
						
Phonograph
Subjects
 - 
						777. 
					
						
Phonograph records
Subjects
Sound recordings
 - 
						778. 
					
						
Photoelectric cells
Subjects
 - 
						779. 
					
						
Photographic equipment
Subjects
 - 
						780. 
					
						
Photographic industry
Subjects
 - 
						781. 
					
						
Photorefractive materials
Subjects
 - 
						782. 
					
						
Photovoltaic cells
Subjects
Photoelectric cells
 - 
						783. 
					
						
Photovoltaic effect
Subjects
Photoelectricity
 - 
						784. 
					
						
Photovoltaic power generation
Subjects
Direct energy conversionSolar energyPhotovoltaic effect
 - 
						785. 
					
						
Photovoltaic power systems
Subjects
Solar power plants
 - 
						786. 
					
						
Physical instruments
Subjects
Scientific apparatus and instruments
 - 
						787. 
					
						
Piezoelectricity
Subjects
CrystallographyElectricity
 - 
						788. 
					
						
Pilot guides
Subjects
NavigationPilotage
 - 
						789. 
					
						
Pilotage
Subjects
Maritime contractsHarbors
 - 
						790. 
					
						
Pipe
Subjects
Hydraulic structuresTransportation
 - 
						791. 
					
						
Pistols
Subjects
WeaponsFirearms
 - 
						792. 
					
						
Plant biotechnology
Subjects
Agricultural biotechnology
 
Last updated dated: 01/11/2025