in recent years there has been considerable interest in the structures, energies and thermodynamics of(gan)4 clusters and it is the subject of many experimental and theoretical studies because of theirfundamental importance in chemical and physical process. all calculation of this study is carried outby gaussian 98. geometry optimization for (gan)4 nanocluster are be fulfilled at b3lyp, b1lypan...

Corresponding to the concept of 'Think globally, act locally and plan regionally' of sustainable development, this paper discusses the approach of planning a sustainable community in terms of systems thinking. We apply a systems tool, the sensitivity model (SM), to build a model of the development of the community of Ping-Ding, located adjacent to the Yang-Ming-Shan National Park, Taiwan. The m...

In this research, the interactions of HCN gas with pristine, Ga-, N- and GaN-doped of boron phosphide nanotube (BPNTs) were investigated by using density function theory (DFT). The structure, electrical and NQR parameters, quantum descriptors involving energy gap, global hardness, global softness, electrophilicity, electronic chemical potential and electronegativity were calculated. The adsorpt...

We report here the epitaxial growth of InGaN/GaN quantum wells on freestanding GaN gratings by molecular beam epitaxy (MBE). Various GaN gratings are defined by electron beam lithography and realized on GaN-on-silicon substrate by fast atom beam etching. Silicon substrate beneath GaN grating region is removed from the backside to form freestanding GaN gratings, and the patterned growth is subse...

The nonpathogenic phenotype of the live rabies virus (RV) vaccine SPBNGAN is determined by an Arg-->Glu exchange at position 333 in the glycoprotein, designated GAN. We recently showed that after several passages of SPBNGAN in mice, an Asn-->Lys mutation arose at position 194 of GAN, resulting in GAK, which was associated with a reversion to the pathogenic phenotype. Because an RV vaccine candi...

Phase pure cubic (c-) GaN/AlGaN heterostructures on 3CSiC free standing (001) substrates have successfully been developed. Almost complete (100%) phase pure c-GaN films are achieved with 2-nm surface roughness on 3C-SiC substrate and stoichiometric growth conditions. The polarization effect in c-GaN/AlGaN has been evaluated, based on measuring the transition energy of GaN/AlGaN quantum wells (Q...

In this work, high quality GaN crystal was successfully grown on C-face 6H-SiC by HVPE using a two steps growth process. Due to the small interaction stress between the GaN and the SiC substrate, the GaN was self-separated from the SiC substrate even with a small thickness of about 100 μm. Moreover, the SiC substrate was excellent without damage after the whole process so that it can be repeate...

We will present a comparison between GaN grown on cand r-plane sapphire by gas-source molecular beam epitaxy (GSMBE) using solid source elemental Ga with untracked ammonia (NH,). Improved GaN film quality was found for samples grown at substrate temperatures above 700°C with optimized temperatures at 780°C. GaN deposited on a low-temperature ( 350°C) GaN buffer layer grown using an if-plasma ra...

In this report, self-organized GaN nanodots have been grown on Si (111) by droplet epitaxy method, and their density can be controlled from 1.1 × 10(10) to 1.1 × 10(11) cm(-2) by various growth parameters, such as substrate temperatures for Ga droplet formation, the pre-nitridation treatment of Si substrate, the nitridation duration for GaN crystallization, and in situ annealing after GaN forma...

We investigate exciton states theoretically in strained GaN/AlN quantum dots with wurtzite ~WZ! and zinc-blende ~ZB! crystal structures, as well as strained WZ GaN/AlGaN quantum dots. We show that the strain field significantly modifies the conductionand valence-band edges of GaN quantum dots. The piezoelectric field is found to govern excitonic properties of WZ GaN/AlN quantum dots, while it h...