Yonghua Chen – författare

This book systematically introduces the most important aspects of organic semiconductor heterojunctions, including the basic concepts and electrical properties. It comprehensively discusses the application of organic semiconductor heterojunctions as charge injectors and charge generation layers in organic light-emitting diodes (OLEDs). Semiconductor heterojunctions are the basis for constructing high-performance optoelectronic devices. In recent decades, organic semiconductors have been increasingly used to fabricate heterojunction devices, especially in OLEDs, and the subject has attracted a great deal of attention and evoked many new phenomena and interpretations in the field. This important application is based on the low dielectric constant of organic semiconductors and the weak non-covalent electronic interactions between them, which means that they easily form accumulation heterojunctions. As we know, the accumulation-type space charge region is highly conductive, which is animportant property for highly efficient charge generation in their application as charge injector and charge generation layer in OLEDs. This book serves as a valuable reference for researchers and as a textbook for graduate students focusing on the study and development of OLED for display and lighting.

This book examines the connotations of the urban safety resilience system and the operational mechanisms of its subsystems. By employing a coupled coordination model, we conduct evaluative analyses across the personnel-facility-management dimensions of urban safety resilience. We provide a comprehensive perspective to help readers understand how disaster risk reduction theories can be applied to various subsystems of urban safety resilience, optimizing disaster management measures in different cities. This book is intended to provide practical guidance for urban planners, policymakers, and researchers, while also being accessible to general readers interested in urban development. The extensive experience and in-depth research of the author''s team make this book a valuable reference for those seeking to explore urban safety resilience.