Perceived Risk of Sharing Other People’s Information on Facebook: The Perspective of Young People in Ho Chi Minh City, Vietnam

Dinh Tien Minh,Tran Ngoc Thuy,Ngo Nguyen Gia Nghi,Nguyen Yen Vy,Nguyen Thi Thanh Lam,Pham Cong Minh KINFORMS 2021 Management Review Vol.16 No.2

In Vietnam, young people are gradually becoming the most accessible objects to social networks. With the development of technology, they usually use online social networks (ONS) as a tool to update information through multimedia content, which may contain other people s information. In different cases, other people s information will be shared and received for different purposes. Therefore, the risk is inevitable and may affect the privacy of individuals whose information is shared, causing turbulence in the community. This study aims to measure impact and find out the factors that influence the willingness of others to share information on social networks in Ho Chi Minh City by examining young people s perceptions that their activities on Facebook may be risky for other people s information. Besides that, the study proposes solutions to avoid possible risks when sharing information with others.

Influences of Au Nanoparticle Density on the Performance of GaAs Solar Cells

Nguyen Dinh Lam,김영호,Kangho Kim,이재진 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.6

The influence of the Au nanoparticle density on the performance of single-junction GaAs solar cellshas been investigated. The single-junction GaAs solar cells are grown on (100) GaAs substrates byusing a low-pressure metalorganic chemical vapor deposition (MOCVD) system. Au nanoparticlesare dispersed on the surfaces of the cells by micro-pipetted casting and the density of the dispersednanoparticles varies from 4.7 × 109 to 4.3 × 1010 cm−2. The conversion efficiencies of the GaAssolar cells are observed to depend strongly on the Au nanoparticle densities. For Au nanoparticledensities lower than 2.8 × 1010 cm−2, the conversion efficiency improvement of the GaAs solarcells mainly originates from the antireflection coating effect. In contrast, for the sample with aAu nanoparticle density of 2.8 × 1010 cm−2, the antireflection effect decreases due to the shadoweffect and the local field enhancement effect due to the Au nanoparticles starts to be effective. TheGaAs solar cell with a Au nanoparticle density of 1.9 × 1010 cm−2 shows a maximum conversionenhancement compared to that of the reference sample.

Activated carbon/g-C₃N₄ /H₂O₂ system with enhanced photocatalytic activity for Rhodamine-B degradation under the visible light

Lan Nguyen Thi,Thi Thuy Trang Phan,Lam Nguyen Tan,Thanh Lieu Thi Le,Le Tuan Nguyen,Nguyen Tien Hoang,Vien Vo,Dinh Quang Khieu 대한환경공학회 2025 Environmental Engineering Research Vol.30 No.1

In this study, activated carbon/g-C₃N₄ photocatalyst (BC/CN) was successfully prepared by a facile calcination method from activated carbons derived from banana peels and urea. As a result, the morphology of BC/CN consisted of the activated carbons highly dispersed on the g-C₃N₄ matrix. The advanced oxidation process of BC/CN and hydogen peroxide exhibits a better catalytic activity towards Rhdamine-B degradation in visible-light region than those of the pristine g-C₃N₄ or BC with hydrogen peroxide. The grafting of activated carbon to g-C₃N₄ enhanced the electron transfer efficiency and suppressed the photoinduced electron-hole recombination. Initial TOC was about 650 mg/L; however, it decreased by 93% to 60 mg/L after 60 min treating. After four cycles of experiments, the catalyst BC/CN still presented high activity for the degradation of RhB. In addition, all N-deethylation intermediates and several small molecular products were separated and identified by LC/MS method. Based on the analytical results, a possible mechanism of photocatalytic degradation was proposed. This work demonstrates a facile and efficient approach to improving the performance of g-C₃N₄-based catalysts.

The Effect of the Ratio of C45 Carbon to Graphene on the Si/C Composite Materials Used as Anode for Lithium-ion Batteries

Hoang Anh Nguyen,Thi Nam Pham,Le Thanh Nguyen Huynh,Tran Ha Trang Nguyen,Viet Hai Le,Nguyen Thai Hoang,Thi Thom Nguyen,Thi Thu Trang Nguyen,Dai Lam Tran,Thi Mai Thanh Dinh The Korean Electrochemical Society 2024 Journal of electrochemical science and technology Vol.15 No.2

Due to its high theoretical capacity, Silicon (Si) has shown great potential as an anode material for lithium-ion batteries (LIBs). However, the large volume change of Si during cycling leads to poor cycling stability and low Coulombic efficiency. In this study, we synthesized Si/Carbon C45:Graphene composites using a ball-milling method with a fixed Si content (20%) and investigated the influence of the C45/Gr ratio on the electrochemical performance of the composites. The results showed that carbon C45 networks can provide good conductivity, but tend to break at Si locations, resulting in poor conductivity. However, the addition of graphene helps to reconnect the broken C45 networks, improving the conductivity of the composite. Moreover, the C45 can also act as a protective coating around Si particles, reducing the volume expansion of Si during charging/discharging cycles. The Si/C45:Gr (70:10 wt%) composite exhibits improved electrochemical performance with high capacity (~1660 mAh g^-1 at 0.1 C) and cycling stability (~1370 mAh g^-1 after 100 cycles). This work highlights the effective role of carbon C45 and graphene in Si/C composites for enhancing the performance of Si-based anode materials for LIBs.

Thermally tunable magnetic metamaterials at THz frequencies

Nguyen Thi Hien,Bui Son Tung,Nguyen Thanh Tung,Vu Dinh Lam 한국자기학회 2015 한국자기학회 학술연구발표회 논문개요집 Vol.2015 No.11

Metamaterials: Detailed parametric studies on cut-wire pair and combined structure

Lam, Vu Dinh,Tung, Nguyen Thanh,Van Hong, Le,Lee, Young Pak Institute of Physics 2009 Journal of physics. Conference series Vol.187 No.1

<P>We studied the electromagnetic behavior of cut-wire pair structure, which is considered as a magnetic metamaterial for designing the left-handed material. It was found that the lattice constant of cut-wire pair structure provides subtle effects not only on the electric resonance but also on the magnetic one. In addition, we also investigated on how this affects the left-handed behavior of combined structures of cut-wire pair and continuous wire. These structures were designed, fabricated, and measured in the microwave frequency regime.</P>

Polarization Dependence of the Metamagnetic Resonance of Cut-wire-pair Structure by Using Plasmon Hybridization

Nguyen Van Dung,유영준,이영백,Nguyen Thanh Tung,Bui Son Tung,Vu Dinh Lam 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.1

The influence of lattice constants on the electromagnetic behavior of a cut-wire-pair (CWP)structure has been elucidated. In this report, we performed both simulations and experiments todetermine the influence of polarization on the metamagnetic resonance of the CWP structure. Thekey finding is the result of an investigation on the plasmon hybridization between the two CWs,which showed that the polarization of the incident wave was affected. Good agreement betweennumerical simulation and measurement is achieved.

Metamaterial Perfect Absorber Using the Magnetic Resonance of Dielectric Inclusions

Nguyen Van Dung,Bui Son Tung,Bui Xuan Khuyen,Young Joon Yoo,YoungPak Lee,Joo Yull Rhee,Vu Dinh Lam 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.68 No.8

In this report, we introduce a stable metamaterial perfect absorber at GHz frequency based on a novel design of a Mie-type resonance. A single perfect absorption peak is achieved at 9.54 GHz, and the influence of the structural parameters on the absorption behavior is studied; the results were consistent with dielectric-resonator theory. The absorption is demonstrated to be polarizationinsensitive; furthermore, the absorber structure can work for a wide incident angle without any change in the resonance peak. Our absorber structure can also control 47% of the resonance peak’s position by changing the temperature of the dielectric layer. Our absorber structure can also be applied as an electromagnetic-wave absorber for wide-incident-angle, thermally-controllable devices.

Fe-MCM-41 with highly ordered mesoporous structure and high Fe content: synthesis and application in heterogeneous catalytic wet oxidation of phenol

Khieu, Dinh Quang,Quang, Duong Tuan,Lam, Tran Dai,Phu, Nguyen Huu,Lee, Jae Hong,Kim, Jong Seung Springer-Verlag 2009 Journal of Inclusion Phenomena and Macrocyclic Che Vol.65 No.1

Novel Anti-Reflection Technology for GaAs Single-Junction Solar Cells Using Surface Patterning and Au Nanoparticles

Kim, Youngjo,Lam, Nguyen Dinh,Kim, Kangho,Kim, Sangin,Rotermund, Fabian,Lim, Hanjo,Lee, Jaejin American Scientific Publishers 2012 Journal of Nanoscience and Nanotechnology Vol.12 No.7

<P>Single-junction GaAs solar cell structures were grown by low-pressure MOCVD on GaAs (100) substrates. Micro-rod arrays with diameters of 2 microm, 5 microm, and 10 microm were fabricated on the surfaces of the GaAs solar cells via photolithography and wet chemical etching. The patterned surfaces were coated with Au nanoparticles using an Au colloidal solution. Characteristics of the GaAs solar cells with and without the micro-rod arrays and Au nanoparticles were investigated. The short-circuit current density of the GaAs solar cell with 2 microm rod arrays and Au nanoparticles increased up to 34.9% compared to that of the reference cell without micro-rod arrays and Au nanoparticles. The conversion efficiency of the GaAs solar cell that was coated with Au nanoparticles on the patterned surface with micro-rod arrays can be improved from 14.1% to 19.9% under 1 sun AM 1.5G illumination. These results show that micro-rod arrays and Au nanoparticle coating can be applied together in surface patterning to achieve a novel cost-effective anti-reflection technology.</P>