Viện Hàn lâm Khoa học và Công nghệ Việt Nam

Công bố khoa học tiêu biểu

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Research on efficient synthetic method of β- and δ-carbolines using a Copper catalyst
Vietnam Journal of Catalysis and Adsorption - Tập 11 Số 4 - Trang 50-56 - 2022
Ban Van Phuc, Nguyen Minh Quan, Nguyen Hien, Nguyen Quyet Tien, Truong Thi Thanh Nga, Nguyen Ngoc Tuan, Nguyen Quang An, Cu Hong Hanh, Dang Thanh Tuan, Tran Quang Hung
Methodology for synthesizing of β- and δ-carboline via two steps reaction from 2,3-dibromopyridine and 3,4-dibromopyridine. The intermediate was prepared from the substrate with o-bromophenylboronic acid via site-selective Suzuki-Myaura reaction, then, the final products were obtained by double C-N coupling via the Ulmann reaction of the intermediate with the corresponding amine with copper cataly...... hiện toàn bộ
#C-N coupling #Ulmann reaction #β-carboline #δ-carboline #copper catalysis
Degradation of reactive blue 182 dye by heterogeneous Fenton reaction using modified fly ash/H2O2
Ninh The Vu, Duc Sy Dao
In this paper, Fe3+ was immobilized in fly ash using a thermal procedure. Fe3+- modified fly ash was used as heterogeneous Fenton catalyst for the degradation of Reactive Blue 182 (RB 182). Some properties of raw and modified fly ashes were characterized by SEM, EDX and XRD techniques. Effects of some key operating parameters such as catalyst dose, pH, and hydrogen peroxide concentration on the tr...... hiện toàn bộ
Mechanism and numerical simulation of a rapid deep-seated landslide in Van Hoi reservoir, Vietnam
Vietnam Journal of Earth Sciences - Tập 45 Số 3 - Trang 357-373 - 2023
Luong Le Hong, Nhan Tran Thanh, Cuong Nguyen Hai, Phi Nguyen Quoc, Quynh Dinh Thi, Trinh Phan Trong, Lan Nguyen Chau, Tien Pham Van, Duc Dao Minh
At approximately 5:00 AM on December 16, 2016, a rapid and deep-seated landslide was triggered by intense rainfall in the Van Hoi irrigation reservoir in Binh Dinh province, Vietnam. The landslide generated an impulsive wave with a height of approximately 20 m, resulting in severe damage to the reservoir operation station. This study investigated the mechanisms behind the landslide's initiation an...... hiện toàn bộ
#Deep-seated landslide #rainfall #pore water pressure #mobility #numerical simulation #Van Hoi reservoir #Vietnam.
ĐÁNH GIÁ TÁC ĐỘNG CỦA KÈ CHẮN SÓNG TỚI QUÁ TRÌNH BỒI -XÓI TẠI KHU VỰC CỬA TAM QUAN, BÌNH ĐỊNH
Vu Tuan Anh
Năm 2009 đê chắn sóng tại cửa Tam Quan được hoàn thành, khu vực này bị bồi một cách nhanh chóng, đặc biệt là vào mùa mưa (trùng hợp với gió mùa Đông Bắc). Các quá trình thủy thạch động lực và xói lở, bồi tụ tại cửa Tam Quan thay đổi theo mùa rõ rệt. Vào mùa mưa (từ tháng 9 tới tháng 12): Gió thịnh hành theo hướng đông bắc (NE), bắc - đông bắc (NNE), bắc (N) và tây bắc (NW). Hầu hết tốc độ gió tập ...... hiện toàn bộ
#Channel #significant wave #discharge #bed materials #accumulate #erosion-deposition.
Synthesis and Optical Properties of Colloidal Gold Nanoparticles for Biomedical Applications
Communications in Physics - Tập 21 Số 1 - 2011
Vu Thi Thuy Duong, Nghiem Thi Ha Lien, Nguyen Van Tinh, Vu Xuan Hoa
The gold nanoparticle solutions are well known as an extremely sensitive biomedical analytical tool due to the strong dependence of their absorption in the visible range on the environment. In this work, the colloidal nano golds were synthesized from metal precursor chloroauric acid (HAuCl4) using trisodium citrate dehydrate (C6H5O7Na3) as reducing and stabilizing agents. The optical characterizat...... hiện toàn bộ
#Colloidal gold #Nanoparticles #Absorption #Surface Plasmon Resonance - SPR}
An approach to study vibration in stochastic systems based on the asymptotic method
Vietnam Journal of Mechanics - Tập 29 Số 3 - 2007
Nguyen Tien Khiem
The well known Fokker-Plank-Kolmogorov Equation Method has been developed to study random vibration in systems with hysteresis that often described by the stochastic integro-differential equations or differential equations with delay.
The application of split step fourier migration to interpreting GPR data in Vietnam
Vo Minh Triet, Nguyen Thanh Van, Nguyen Van Thuan, Nguyen Van Giang, Dang Hoai Trung
Migration methods play an essential role in processing ground penetrating radar data. For estimating electromagnetic propagation velocity distribution, the finite - difference migration is used because of its reliable performance with high noise conditions. To optimize this migration algorithm, we propose using energy diagram as a criterion of looking for the correct velocity. If the velocity vari...... hiện toàn bộ
#Split Step Fourier Migration #energy diagram #finite - difference migration.
Application of satellite images and VNREDSAT-1 images in study on marine environment in Truong Sa region
Tran Xuan Loi, Nguyen Xuan Tung, Pham Duc Hung, Do Huy Cuong, Le Dinh Nam, Bui Thi Bao Anh, Nguyen Thi Nhan, Nguyen The Luan
The remote sensing images, including images of MODIS, VNREDSAT-1 and altimeter, are applied for researching marine environment with the different resolutions. On the basis of different time remote sensing images, we concentrated on the assessment of several characteristics including the SST, chlorophyll-a concentration and sea surface current at the different depths in different monsoons as well. ...... hiện toàn bộ
#Remote sensing image #marine environment #sea surface temperature (SST) #chlorophyll-a concentration #sea current.
Dynamic analysis of prestressed Bernoulli beams resting on two-parameter foundation under moving harmonic load
Vietnam Journal of Mechanics - Tập 28 Số 3 - 2006
Nguyen Dinh Kien, Bui Thanh Hai
This paper describes the dynamic analysis of prestressed Bernoulli beams resting on a two-parameter elastic foundation under a moving harmonic load by the finite element method. Using the cubic Hermitian polynomials as interpolation functions for the deflection, the stiffness of the Bernoulli beam element augmented by that of the foundation support and prestress is formulated. The nodal load vecto...... hiện toàn bộ
Ground displacement of the 6 July 2019 Ridgecrest earthquake from the GNSS permanent stations
Vietnam Journal of Earth Sciences - Tập 41 Số 4 - 2019
Binh Thai Pham, Nguyen Ngoc Lau, Tran Van Phong, Phan Trong Trinh
The Eastern California earthquake (also known as the Ridgecrest earthquake) occurred at 03:19:53 (UTC) on the 6th of July, with a moment magnitude of 7.1. Over the region, there is an accurate network of GNSS permanent stations. Precise determination of displacements of these stations will provide important information to better understand the structure and scope of the earthquake, contributing to...... hiện toàn bộ
#The 6th of July #2019 Ridgecrest earthquake #GNSS #PPP #California
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