................................................................................................................................................. 1 PREFACE .....................................................................................................................................................

...................................................................................................................................... i Nomenclature ........................................................................................................................... iii Preface...................................................................................................................

........................................................................................................................... iii Preface ................................................................................................................................ v Acknowledgements ......................................................................................................... vii

xiv Preface xvi Acknowledgements xviii

....................................................................................................................................... ii Preface ......................................................................................................................................... iii Table of

Perspectives and Techniques Preface ..............................................................................................................v

iii Tiivistelmä v Preface vii

.......................................................................................................................................... ii Preface ........................................................................................................................................... iv Table of

Abstract In this preface of the Special Issue on Future Directions Further Developments in Mathematics, we discuss about mathematics, how it should be, what was and hope will develop.

The research situation of the application carbon quantum dot fluorescent materials to detection metal ions, including current status and preface recent years, development trends are summarized. ions is highlighted, iron copper mercury lead silver ions. Finally, problems prospects for detecting discussed.