This book contains eight chapters. In the first chapter of this book, selective and sensitive fluorescent sensor for lead ion, in the second chapter the viability of biochar-doped hydrogels in the fight against drought, in the third chapter simultaneous determination cholesterol-reducing combinatıon using principal components regression method, in the fourth chapter the effect of high electrical power on the physical structure of graphene nanosheets produced by anodic electrochemical exfoliation process, in the fifth chapter dynamic nuclear polarization parameters of nitroxide radical with 4-fluorobenzylamine, in the sixth chapter vajda theorems of jacobsthal and jacobsthal-lucas octonions, in the seventh chapter physicochemical properties of zeolite and modified zeolite clay, nanocatalyst and nanoadsorbent supported applications and in the eighth chapter bionanocomposites as fungicide against phytopathogenic fungi is examined.