Hydrogenic impurity states in wurtzite symmetric ZnO/MgZnO coupled quantum dots

Shuyi Wei,Qing Chang,Zaiping Zeng 한국물리학회 2011 Current Applied Physics Vol.11 No.1

Within the framework of effective-mass approximation, the ground-state donor binding energy of a hydrogenic impurity in cylindrical wurtzite (WZ) symmetric ZnO/MgZnO strained coupled quantum dots (QDs) is calculated by means of a variational method, considering the strong built-in electric field induced by the spontaneous and piezoelectric polarizations. Numerical results show that the strong built-in electric field induces an asymmetric distribution of the donor binding energy with respect to the center of the coupled QDs. When the impurity is located at the center of the dot which is opposite to the growth direction, the donor binding energy has a maximum value with increasing dot height; and it is also insensitive to the middle barrier width if the middle barrier width is large. Moreover, numerical results also indicate that the donor binding energy of impurity located at the right boundary of the dot which is opposite to the growth direction is insensitive to the Mg composition if the Mg composition is large.

중국시장으로의 글로벌 브랜드 전략을 위한 탐색적 연구:패션브랜드 "이랜드"를 중심으로

주미, 진주이, 이재덕, 김은영 충북대학교 생활과학연구소 2012 생활과학연구논총 Vol.16 No.2

This study explores a strategic marketing for global fashion branding into Chinese market. Literatures were to analyze the Chinese market situation and to identify the success factors of E-land global brand strategy in China. As a qualitative approach, this study conducted a focus group interview with 10 Chinese panels aged from 21 to 24 years. All responses were audio recorded and transcribed. A total of 447 transcribed responses were analysis by using content analysis with regularity and frequency of responses. Results showed that Chinese motives to purchase clothing included situational and individual reasons for variety seeking or self expression. They tended to importantly consider the aesthetics, quality, price and service when purchasing clothing. Chinese consumers were most highly aware of European fashion brands, and followed by US, Korean and Japanese brands. In addition, perceived brand image were classified into three factors: classic image for Korean brands, casual & simple image for US brands, and chic image for European brands. In the case of Korean brand "E-land", Chinese consumers had positive attitude in the aspects of quality and performance, coordination and brand image, whereas they had negative attitude in the aspects of product assortment, price, and premium image. This study discussed a managerial implication for global fashion marketing in the Chinese marketplace.

The impact of microphysical schemes on hurricane intensity and track

Tao, Wei-Kuo,Shi, Jainn Jong,Chen, Shuyi S.,Lang, Stephen,Lin, Pay-Liam,Hong, Song-You,Peters-Lidard, Christa,Hou, Arthur Springer-Verlag 2011 Asia-Pacific Journal of Atmospheric Sciences Vol.47 No.1

중국시장으로의 글로벌 브랜드 전략을 위한 탐색적 연구

주미(Wei Zhou),진주이(Shuyi Chen),이재덕(Jaedeok Lee),김은영(Eun Young Kim) 충북대학교 생활과학연구소 2012 생활과학연구논총 Vol.16 No.2

This study explores a strategic marketing for global fashion branding into Chinese market. Literatures were to analyze the Chinese market situation and to identify the success factors of E-land global brand strategy in China. As a qualitative approach, this study conducted a focus group interview with 10 Chinese panels aged from 21 to 24 years. All responses were audio recorded and transcribed. A total of 447 transcribed responses were analysis by using content analysis with regularity and frequency of responses. Results showed that Chinese motives to purchase clothing included situational and individual reasons for variety seeking or self expression. They tended to importantly consider the aesthetics, quality, price and service when purchasing clothing. Chinese consumers were most highly aware of European fashion brands, and followed by US, Korean and Japanese brands. In addition, perceived brand image were classified into three factors: classic image for Korean brands, casual & simple image for US brands, and chic image for European brands. In the case of Korean brand "E-land", Chinese consumers had positive attitude in the aspects of quality and performance, coordination and brand image, whereas they had negative attitude in the aspects of product assortment, price, and premium image. This study discussed a managerial implication for global fashion marketing in the Chinese marketplace.

Engineering a Highly Thermostable and Stress Tolerant Superoxide Dismutase by N-terminal Modification and Metal Incorporation

Mingchang Li,Shuyi Guo,Xiaomin Li,Quan Wang,Lin Zhu,Chunyan Yin,Wei Wang 한국생물공학회 2017 Biotechnology and Bioprocess Engineering Vol.22 No.6

Thermophilic or hyperthermophilic SODs (superoxide dismutase) usually offer substantial biotechnological advantages over mesophilic SODs. Previously a 244-amino acid N-terminal domain (NTD) from a heatresistant SOD of Geobacillus thermodenitrificans NG80-2 was discovered and demonstrated to be able to confer thermostability to homologous mesophilic SODs, which revealed a new type of heat resistance mechanism. To further improve the heat resistance and stress tolerance of thermophilic cambialistic superoxide dismutase (Fe/Mn- SODAp) from Aeropyrum pernix K1 through metal incorporation and fusion with the newly found peptide NTD for broadening its industrial application, the wildtype SODAp and NTD-fused ntdSODAp were expressed in E. coli BL21 and incorporated with metal cofactors by two ways. Recombinant fusion SOD obtained by in vitro reconstitution (Mn-rec ntdSODAp) exhibited improved optimum temperature at 70oC and dramatically enhanced thermostability especially at 110oC with enhanced pH stability from 4 to 10 and higher tolerance for denaturants and organic media than Mn-rec SODAp. To the best of our knowledge, Mn-rec ntdSODAp could be the most heat resistant SOD. In addition, metal incorporation of SODAp and ntdSODAp via in vivo modification have been developed and proved to be more practical for industrial use. These results indicate that fusion with NTD along with metal incorporation can generate superimposed effect and be applied to enhance the stability of cambialistic thermophilic SODs, thus providing a universal and convenient bioengineering method for generating extremely stable SODs.

The donor bound exciton states in wurtzite GaN quantum dot

Yaming Liu,Congxin Xia,Shuyi Wei 한국물리학회 2009 Current Applied Physics Vol.9 No.1

Based on the effective mass approximation, the donor bound exciton states in a wurtzite (WZ) GaN/AlGaN quantum dot (QD) are investigated by means of a variational method, including the strong built-in electric field effect due to the spontaneous and piezoelectric polarizations. Numerical results show that the donor bound exciton binding energy is highly dependent on the impurity position and QD size. In particular, we find that the donor bound exciton binding energy is insensitive to dot height when the impurity is located at the right boundary of the WZ GaN/AlGaN QD with large dot height. Based on the effective mass approximation, the donor bound exciton states in a wurtzite (WZ) GaN/AlGaN quantum dot (QD) are investigated by means of a variational method, including the strong built-in electric field effect due to the spontaneous and piezoelectric polarizations. Numerical results show that the donor bound exciton binding energy is highly dependent on the impurity position and QD size. In particular, we find that the donor bound exciton binding energy is insensitive to dot height when the impurity is located at the right boundary of the WZ GaN/AlGaN QD with large dot height.

Exciton states in zinc-blende InGaN/GaN quantum dot

Congxin Xia,Fengchn Jiang,Shuyi Wei 한국물리학회 2008 Current Applied Physics Vol.8 No.2

Within the framework of effective-mass approximation, exciton states confined in zinc-blende(ZB) InGaN/GaN quantum dot(QD) are investigated by means of a variational approach, considering finite band offsets. The ground-state exciton binding energy and the interband emission energy are investigated as functions of QD structural parameters in detail. Numerical results show clearly that both the QD size and In content of InGaN have a significant influence on the exciton states and interband optical transitions in the ZB InGaN/GaN QD. Within the framework of effective-mass approximation, exciton states confined in zinc-blende(ZB) InGaN/GaN quantum dot(QD) are investigated by means of a variational approach, considering finite band offsets. The ground-state exciton binding energy and the interband emission energy are investigated as functions of QD structural parameters in detail. Numerical results show clearly that both the QD size and In content of InGaN have a significant influence on the exciton states and interband optical transitions in the ZB InGaN/GaN QD.