Tachyon Beam and Charged Particle Burst aren't very effective at the moment. Gravity Well 3 with the Gravimetric Scientist duty officer and points in Particle Generators can be very effective with high aux power. You could also try Energy Siphon with points into Flow Capacitors to boost your power levels (particularly weapon power). Tractor Beam Repulsors can do great damage with points in Particle Generators but they're difficult to control.
Sci in PvP needs to balance between damage and healing because it's difficult to survive long enough to DPS due to low hull and defense. You might want to focus primarily on keeping yourself alive. Hard to do damage when you're dead