Yes, Leonid Kulik is a noun, a propernoun, the name of a person (noted Russian scientist). A proper noun is always capitalized.
Leonid Kulik died on 1942-04-24.
Leonid Kulik was born on 1883-08-19.
Buzz Kulik's birth name is Kulik, Seymour.
Ilia Kulik's birth name is Ilia Alexandrovich Kulik.
Elizaveta Kulik's birth name is Elizaveta Ilinichna Kulik.
Valentin Kulik's birth name is Valentin Yakovlevitch Kulik.
Yuri Kulik's birth name is Yuri Vladimirovitch Kulik.
Stephen Kulik was born in 1956.
Ivan Kulik was born in 1897.
Ivan Kulik died in 1937.
Johann Kulik died in 1872.
Johann Kulik was born in 1800.