can i use this to put my nikon dx af-s nikkor 35mm 1.1.8g lens on m panasonic lumix gh1?
Yes it will fit, the lens will become completely manual though. Not familiar with that lens, but hopefully it has a aperture adjustment ring, otherwise you have to use the ring on the adapter which isn't very accurate and doesn't have any number markings. But to answer your question, yes, and good quality.
Yes, but you will have to focus manually and set the aperture blindly using the adapter's aperture ring. You can guess the aperture by always starting with it wide open and then watch the shutter speed change as you stop down. It works but shooting that way gets old fast. Buy an m4/3 35mm!