Reverse graded relaxed buffers for high Ge content SiGe virtual substrates

An innovative approach is proposed for epitaxial growth of high Ge content, relaxed Si1−xGex buffer layers on a Si(001) substrate. The advantages of the technique are demonstrated by growing such structures via chemical vapor deposition and their characterization. Relaxed Ge is first grown on the substrate followed by the reverse grading approach to reach a final buffer composition of 0.78. The optimized buffer structure is only 2.8 µm thick and demonstrates a low surface threading dislocation density of 4×106 cm−2, with a surface roughness of 2.6 nm. The buffers demonstrate a relaxation of up to 107%

The synthesis and characterization of new higher nuclearity arene-ruthenium-sulfur clusters : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Chemistry at Massey University, New Zealand

This thesis describes a project investigating the synthesis and characterization of new higher nuclearity arene-ruthenium-sulfur clusters and arene-ruthenium-nitrogen complexes. The thesis is divided into four chapters, with the introduction in Chapter One. The synthesis and characterization of new higher nuclearity arene-ruthenium-sulfur clusters are described in Chapter Two. These include two novel clusters, [Ru₅S₄(cymene)₄](PF₆)₂, [Ru₄(S₂)(SO)(cymene)₄](PF₆)₂ and one known cluster, [Ru₃S₂(cymene)₃](PF₆)₂. The X-ray crystallographic structures of these three arene-ruthenium-sulfur clusters are discussed in detail including how the number of valence electrons influences the structure, how the solid state structure and single crystal structure effect each other and how the structures determine the chemical shifts and other characters of the clusters. The unusual signals of these three clusters on ¹H NMR spectra are discussed carefully. The mechanisms of formation of arene-ruthenium-sulfur clusters are described in detail. Some electrochemistry and calculations (quantum chemistry) are also involved. The synthesis and characterization of arene-ruthenium-nitrogen complexes are described in Chapter Three. These include two new mono-nuclear complexes, [RuCl₂(NH₃)(cymene)], [Ru(NH₃)₃(cymene)](PF₆)₂, one novel amide dimer [RuCl(NH₂)(cymene)]₂ and one known complex, [RuCl(NH₃)₂(cymene)]PF₆. The mechanisms of reactions in which they are formed are also discussed. In Chapter Four, the experimental data is presented. The X ray crystallography of [Ru₅S₄(cymene)₄](PF₆)₂, [Ru₄(S₂)(SO)(cymene)₄](PF₆)₂, [RuCl₂(NH₃)(cymene)] and [RuCl(NH₂)(cymene)]₂ is described in detail

Tuning pKa in new molecules based on indolines for two-photon absorption bioimaging applications

Fluorescence-based biosensors have become essential tools for modern biology, allowing real-time monitoring of biological processes within living cells. The differences between pH play a significant role in multiple biological process such as proliferation, apoptosis, endocytic process and defense. Therefore, intracellular fluorescent pH probes comprise one of the most widely used families of biosensors in microscopy. In this work, we present the design, synthesis and characterization of new one and two photon pH activatable fluorescent probes based on naphthalene-indoline derivatives with an off-on response to different pH environments. These compounds are easy to achieve with good yields and have good photophysical properties. Simple modifications in the structure of these compounds allow tuning their pKa easily and cover a width range of pH in their applications. The preliminary results obtained with these fluorescent probes indicate that they have promising properties to be use in bioimaging applications in living cells.Real Sociedad Española de Química y Grupo Especializado de Química Orgánica de la RSEQ•Universidade de Santiago de Compostela • CIQUS • Lilly • Mestrelab Research •Thieme •Scharlab • Acros • ABCR • AMSLab • GalChimia • Elsevier • The Journal of the American Chemical Society • ACS Omega • Organic Letters • The Journal of Organic Chemistry • Accounts of Chemical Research. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech