Tìm kiếm

Tiêu chí lọc:


Tiêu chí lọc:


Tác giả

Chủ đề

Năm xuất bản

Kết quả tìm kiếm

Hiện thị kết quả từ 31 đến 40 của 352
  • Tác giả : Nguyen, Ha Anh; Mai, Quan Doan; Ngo, Xuan Dinh; Tran, Quang Huy; Doa,n Quang Tri; Le, Thi Ngoc Loan; Bui, Van Hao; Le, Anh Tuan;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    Modern society has been facing serious health-related problems including food safety, diseases and illness. Hence, it is urgent to develop analysis methods for the detection and control of food contaminants, disease biomarkers and pathogens. As the traditional instrumental methods have several disadvantages, including being time consuming, and having high cost and laborious procedures, optical nanosensors have emerged as promising alternative or complementary approaches to those traditional ones. With the advantages of simple preparation, high surface-to-volume ratio, excellent biocompatibility, and especially, unique optical properties, gold nanoparticles (AuNPs) have been demonstrated as excellent transducers for optical sensing systems. Herein, we provide an overview of the synth...

  • Tác giả : Tran, Quoc Quan; Do, Thi Thu Ha; Nguyen, DinhDuc;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    This paper presents the nonlinear vibration of porous functionally graded sandwich plate on elastic foundations subjected to blast loading by the analytical approach. The sandwich plate consists of two FGM face sheets and a homogeneous core which is made from metal or ceramic. Two types of porosity distribution, including evenly and unevenly distributed porosity have been considered for sandwich plate. The material properties of sandwich plate are assumed to vary in the thickness direction according to simple power law distribution with a volume fraction index and a porosity coefficient. The blast loading is assumed to be uniformly distributed on the surface of the sandwich plate and modeled by an exponential function. The Reddy’s higher order shear deformation theory with von Kármá...

  • Tác giả : L.T.Anh; P.V.Cuong; H.T.Thao; N.H.Tan; K.T.Thanh;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    In this work, we developed a Geant4-based code, IS-2020, for photonuclear studies below 200 MeV covering the giant dipole resonance region (GDR). It uses G4LowEGammaNuclearModel, which consists of preequilibrium and equilibrium reaction mechanisms, for sampling the final states of photonuclear reactions. Simulations for photonuclear reactions on 96Mo, 90Zr, and the strongly-deformed nucleus 153Eu targets have been performed for its validation. Moreover, a good agreement was also observed between experimental relative yields and the simulation results of 59Co(,2n)57Co and 50Cr(,2n)48Cr reactions induced by bremsstrahlung. The implemented code will be a useful and reliable tool for photonuclear studies, including designing the experimental setup, estimating the yield of outgoing produ...

  • Tác giả : Mai Quan Doan; Nguyen Ha Anh; Hoang Van Tuan; Nguyen Cong Tu; Nguyen Huu Lam; Nguyen Tien Khi; Vu Ngoc Phan; Pham Duc Thang; Anh-Tuan Le;  Người hướng dẫn: -;  Đồng tác giả: - (2021)

    Multifunctional nanocomposites have received great attention for years; electron transfer (ET) is considered as an explanatory mechanism for enhancement of performance of these nanostructures. The existence of this ET process has been proved in many studies using either experimental or computational approaches. In this study, a ternary nanocomposite system of Ag/TiO2/GO was prepared to evaluate the performance enhancement in two experimental models: a physical model (i.e., surface-enhanced Raman scattering (SERS) sensor) and a chemical one (i.e., catalytic reduction reaction). The metal/semiconductor heterojunction between Ag and TiO2, as well as Ti-O-C bonds, has allowed plasmonic hot electrons to be transferred in the internal structure of the material. An investigation on the rol...

  • Tác giả : Tran, Quoc Quan; Do, Thi Thu Ha; Nguyen, Dinh Duc;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    This paper presents the nonlinear vibration of porous functionally graded sandwich plate on elastic foundations subjected to blast loading by the analytical approach. The sandwich plate consists of two FGM face sheets and a homogeneous core which is made from metal or ceramic. Two types of porosity distribution, including evenly and unevenly distributed porosity have been considered for sandwich plate. The material properties of sandwich plate are assumed to vary in the thickness direction according to simple power law distribution with a volume fraction index and a porosity coefficient. The blast loading is assumed to be uniformly distributed on the surface of the sandwich plate and modeled by an exponential function. The Reddy’s higher order shear deformation theory with von Kármá...

  • Tác giả : Nguyen, Ngoc Huyen; Ngo, Xuan Dinh; Mai, Quan Doan;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    In this work, we investigated the effect of morphology on the analytical performance of α-Fe2O3 nanostructures-based electrochemical sensors toward chloramphenicol (CAP) antibiotic using three designed morphologies including α-Fe2O3 nano-tube (α-Fe2O3-T), α-Fe2O3 nano-rice (α-Fe2O3-R), and α-Fe2O3 nano-plate (α-Fe2O3-P). Among these morphologies, α-Fe2O3-T displayed an outstanding electrochemical activity owing to the unique hollow structure and large specific surface area. However, due to the small pores size, α-Fe2O3-T showed the high steric hindrance (SD) effect towards an antibiotic with complex molecular structure, as CAP, leading to a significant decrease of their CAP electrochemical sensing performance. The CAP analytical performance of α-Fe2O3-R was highest in investigated m...

  • Tác giả : Abdullah H. Alshehri; Jhi Yong Loke; Viet Huong Nguyen; Alexander Jones; Hatameh Asgarimoghaddam; Louis-Vincent Delumeau; Ahmed Shahin; Khaled H. Ibrahim; Kissan Mistry; Mustafa Yavuz; David Muñoz-Rojas; Kevin P. Musselman;  Người hướng dẫn: -;  Đồng tác giả: - (2021)

    Nanoscale films are integral to all modern electronics. To optimize device performance, researchers vary the film thickness by making batches of devices, which is time-consuming and produces experimental artifacts. Thin films with nanoscale thickness gradients that are rapidly deposited in open air for combinatorial and high-throughput (CHT) studies are presented. Atmospheric pressure spatial atomic layer deposition reactor heads are used to produce spatially varying chemical vapor deposition rates on the order of angstroms per second. ZnO and Al2O3 films are printed with nm-scale thickness gradients in as little as 45 s and CHT analysis of a metal-insulator-metal diode and perovskite solar cell is performed. By testing 360 Pt/Al2O3/Al diodes with 18 different Al2O3 thicknesses on o...

  • Tác giả : Xiaoyu, Zhang; Thien Van, Luong; Periklis, Petropoulos;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    End-to-end learning systems are conceived for Orthogonal Frequency Division Multiplexing (OFDM)-aided optical Intensity Modulation paired with Direct Detection (IM/DD) communications relying on the Autoencoder (AE) architecture in deep learning. We first propose an AE-aided Layered ACO-OFDM (LACO-OFDM) scheme, termed as LACONet, for exploiting the increased bandwidth efficiency of LACO-OFDM. LACONet employs a Neural Network (NN) at the transmitter for bit-to-symbol mapping, and another NN at the receiver for recovering the data bits, which together form an AE and can be trained in an end-to-end manner for simultaneously minimizing both the BER and PAPR. Moreover, the detection architecture of LACONet is drastically simplified compared to classical LACO-OFDM, since the Fast Fourier T...

  • Tác giả : Nguyen, Ha Anh; Mai, Quan Doan; Ngo, Xuan Dinh;  Người hướng dẫn: -;  Đồng tác giả: - (2022)

    Electrochemically synthesized gold nanoparticles (e-AuNPs) were deposited on aluminum substrates to fabricate effective surface enhanced Raman spectroscopy (SERS) sensors for thiram and CAP monitoring in food samples, between which the thiram sensor showed better performance in terms of sensibility, reliability and practicability. Regarding that the differences in SERS performance of the two sensors were closely associated to the distinction in molecular structure of the two analytes, we investigated the effects of analyte molecular structure on the sensing performance, especially the enhancement factors (EFs), of the sensors. As the enhancement of SERS signal is explained by both chemical and electromagnetic mechanisms (CM and EM), the investigation was also carried out in two dire...