Other contributors have said "Debenzylation by using palladium and carbon?" is the same question as "What do you use palladium for?" If you believe that these are not asking the same thing and should be answered differently, click here
Using " Has " is referred a past tense. Such as: He has taken the garbage out already. Using " Is " for example is referred a Present tense. Such as: He is taking out the garbage.
Related ads:
Shopping for Investing and Financial Markets deals?
Find Coupons and Promo Codes on Coupons by Answers.com