Relaxor characteristics of PSLZT-BMT-based ferroelectric material ceramics

Nguyen Van Thinh,Le Dai Vuong,Do Viet On,Truong Van Chuong,Le Vu Truong Son,Trinh Ngoc Dat,Le Van Thanh Son,Vo Thanh Tung 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.3

(1-x)[(Pb0.94Sr0.05La0.01)(Zr0.54Ti0.46)0.9975O3]-x[Bi(Mn1/2Ti1/2)O3] (PSLZT-BMT) ferroelectric material ceramics with x in therange of 0-0.05 mol were successfully synthesized following the conventional solid-phase route. The materials were thoroughlyinvestigated to study their structural phase, microstructure, ferro-piezoelectric characteristics, and dielectric behavior. Theexperimental results show that the density of the samples decreased from 7.75 to 7.58 g/cm3, and the relative density decreasedin the range of 98.48%-96.28%. However, with increasing contents of BMT, the dielectric and ferroelectric properties ofPSLZT-BMT ceramics tend to decrease, specifically the maximum dielectric constant (εmax) of PSLZT-BMT decreased in therange of 23579-9991 and the residual polarization (Pr) decreases in the range of 22.54-7.87 μC/cm2 when the doping contentincreased in the range of 0.0-0.05 mol. The diffusivity values (γ) of the PSLZT-BMT material are 1.74, 1.78, 1.82, 1.84, 1.79,and 1.77 when the doping content x varies as 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05 mol, respectively, which is characteristic ofrelaxor ferroelectric materials. Besides, the Tm, TB, TC-W, and C values depend on BMT concentration, and the trend decreases.

Expression of Two Potential Membrane Protein ORF25 and OF131 of Koi Herpes Virus (Cyprinid Herpesvirus-3) in E. coli

Le Van Truong,Seong Joon Joh,Hwan Jang,Tae Sung Jung,Jun Hun Kwon 대한수의학회 2009 대한수의학회 학술대회발표집 Vol.2009 No.-

Improvement of the aerodynamic performance by wing flexibility and elytra–hind wing interaction of a beetle during forward flight

Le, Tuyen Quang,Truong, Tien Van,Park, Soo Hyung,Quang Truong, Tri,Ko, Jin Hwan,Park, Hoon Cheol,Byun, Doyoung Royal Society 2013 Journal of the Royal Society, Interface Vol.10 No.85

<P>In this work, the aerodynamic performance of beetle wing in free-forward flight was explored by a three-dimensional computational fluid dynamics (CFDs) simulation with measured wing kinematics. It is shown from the CFD results that twist and camber variation, which represent the wing flexibility, are most important when determining the aerodynamic performance. Twisting wing significantly increased the mean lift and camber variation enhanced the mean thrust while the required power was lower than the case when neither was considered. Thus, in a comparison of the power economy among rigid, twisting and flexible models, the flexible model showed the best performance. When the positive effect of wing interaction was added to that of wing flexibility, we found that the elytron created enough lift to support its weight, and the total lift (48.4 mN) generated from the simulation exceeded the gravity force of the beetle (47.5 mN) during forward flight.</P>

Synthesis of Nano Titanium Dioxide and Its Application in Photocatalysis

Truong Van Chuong,Le Quang Tien Dung,Dinh Quang Khieu 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.5

This paper presents a simple way to synthesize titaniumdioxide nanotubes by using a microwave- assisted reaction of TiO2 particles and NaOH solution. The main advantage of the introduction of microwave into the reaction system is the extremely rapid kinetics for synthesis. This method is simple and easy to reproduce. Structural and microstructural characterizations of titania nanotubes were accomplished using X-ray diffraction (XRD), scanning-electron microscopy (SEM) and transmission-electron microscopy (TEM) techniques. The specific surface area was calculated using the Brunauer-Emmett-Teller model and was found to be 52 m2/g. A high photocatalysis of our TiO2 nanotubes was obtained. This paper presents a simple way to synthesize titaniumdioxide nanotubes by using a microwave- assisted reaction of TiO2 particles and NaOH solution. The main advantage of the introduction of microwave into the reaction system is the extremely rapid kinetics for synthesis. This method is simple and easy to reproduce. Structural and microstructural characterizations of titania nanotubes were accomplished using X-ray diffraction (XRD), scanning-electron microscopy (SEM) and transmission-electron microscopy (TEM) techniques. The specific surface area was calculated using the Brunauer-Emmett-Teller model and was found to be 52 m2/g. A high photocatalysis of our TiO2 nanotubes was obtained.

Some Experiences in Veterinary Training at the Faculty of Animal and Veterinary Science (FAVS)-Hanoi Agricultural University (HAU)

Le Van Lanh,Truong Quang 대한수의학회 2001 대한수의학회 학술대회발표집 Vol.2001 No.-

Experimental study on mechanical behaviors of injection molded PC/PMMA blends

Van Thanh Hoang,Quang Bang Tao,Bich-Tram Truong-Le,Minh Sang Tran,Duc Binh Luu 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.9

Mechanical property is one of the quite important factors of optical articles. Most of pure plastics materials are rarely found to have both high strength and toughness. The paper aims to investigate mechanical properties of polymethyl methacrylate and polycarbonate (PC/PMMA) blends by means of injection molding process and optimization technique. In this study, four factors including composition, packing pressure, melt temperature, and cooling time are taken into account. Experimental results show that the composition is found as the most significant factor for improving the mechanical properties of PC/PMMA blends with confidence level of 95 %. Meanwhile, melt temperature and cooling time are also the most significant parameters for enhancing impact strength with 95 % confidence level. In addition, the mechanical properties of the PC/PMMA plastics composites have been enhanced significantly. Specifically, average tensile yield strength, impact strength, and average elongation are 76.5 MPa, 7429.5 J/m 2 , and 17.5 mm, respectively.

Experimental and numerical studies of beetle-inspired flapping wing in hovering flight

Van Truong, Tien,Le, Tuyen Quang,Park, Hoon Cheol,Byun, Doyoung IOP Publishing 2017 Bioinspiration & biomimetics Vol.12 No.3

<P>In this paper, we measure unsteady forces and visualize 3D vortices around a beetle-like flapping wing model in hovering flight by experiment and numerical simulation. The measurement of unsteady forces and flow patterns around the wing were conducted using a dynamically scaled wing model in the mineral-oil tank. The wing kinematics were directly derived from the experiment of a real beetle. The 3D flow structures of the flapping wing were captured by using air bubble visualization while forces were measured by a sensor attached at the wing base. In comparison, the size and topology of spiral leading edge vortex, trailing edge vortex and tip vortex are well matched from experimental and numerical studies. In addition, the time history of forces calculated from numerical simulation is also similar to that from theforce measurement. A difference of average force is in order of 10 percent. The results indicate that the leading edge vortex due to rotational acceleration at the end of the stroke during flapping wing causes significant reduction of lift. The present study provides useful information on hover flight to develop a beetle-like flapping wing Micro Air Vehicle.</P>

An online Indigenous Knowledge Database on Climate Change Adaptation of Farmers in the Vietnam Mekong Delta

Van Hoa Nguyen,Thi Mai Phung Bui,Thanh Phong Le,Hoang Tung Nguyen,Minh Tuyen Truong,Minh Nhut Do,Van Nha Duong 인간식물환경학회 2022 인간식물환경학회지 Vol.25 No.6

Background and objective: For countries vulnerable to climate change as Vietnam, indigenous knowledge (IK) might assist in revealing the values of local people's adaptations to environmental stresses and potentially support decision-making. Despite IK can provide the adaptive capacity of local people's activities within environmental contexts, but it is rapidly vanishing. This study aimed to describe the documentation of IK associated with climate change adaptation of farmers in the Vietnam Mekong Delta (VMD). Methods: We focused on collecting and establishing online access to IK documents through collaboration between IK holders, public sector, collecting institutions, and researchers in the five agro-ecological zones of the VMD. An online IK database for storing IK documents has been designed and implemented based on the web application schema. Results: Through interviews, we gathered IK from farming practices that are well-adapted to climate risks such as floods, droughts, and saltwater intrusions as well as traditional knowledge being used to forecast weather, flood, and saltwater intrusion. The database for storing IK documents has been successfully deployed using free and open-source software. The database currently contains more than 260 IK documents, with their location on agro-ecological zones displayed on a web-based map. Conclusion: We have captured and provided an online access to IK on climate change adaptation of the farmers in the VMD. This research is expected as an initial strategy for long-term sustainable development of the agriculture system in this region.

Parenchymal-sparing anatomical hepatectomy based on portal ramification of the right anterior section: A prospective multicenter experience with short-term outcomes

Truong Giang Nguyen,Thanh Khiem Nguyen,Ham Hoi Nguyen,Hong Son Trinh,Tuan Hiep Luong,Minh Trong Nguyen,Van Duy Le,Hai Dang Do,Kieu Hung Nguyen,Van Minh Do,Quang Huy Tran,Cuong Thinh Nguyen 한국간담췌외과학회 2024 Annals of hepato-biliary-pancreatic surgery Vol.28 No.1

Backgrounds/Aims: Parenchymal-sparing anatomical hepatectomy (Ps–AH) based on portal ramification of the right anterior section (RAS) is a new technique to avoid unnecessarily transecting too much liver parenchyma, especially in cases of major anatomical hepatectomy. Methods: We prospectively assessed 26 patients with primary hepatic malignancies having undergone major Ps–AH based on portal ramification of the RAS from August 2018 to August 2022 (48 months). The perioperative indications, clinical data, intra-operative index, pathological postoperative specimens, postoperative complications, and follow-up results were retrospectively evaluated. Results: Among the 26 patients analyzed, there was just one case that had intrahepatic cholangiocarcinoma The preoperative level of α– Fetoprotein was 25.2 ng/mL. All cases (100%) had Child–Pugh A liver function preoperatively. The ventral/dorsal RAS was preserved in 19 and 7 patients, respectively. The mean surgical margin was 6.2 mm. The mean surgical time was 228.5 minutes, while the mean blood loss was 255 mL. In pathology, 5 cases (19.2%) had microvascular invasion, and in the group of HCC patients, 92% of all cases had moderate or poor tumor differentiation. Six cases (23.1%) of postoperative complications were graded over III according to the Clavien–Dindo system, including in three patients resistant ascites or intra-abdominal abscess that required intervention. Conclusions: Parenchymal-sparing anatomical hepatectomy based on portal ramification of the RAS to achieve R0-resection was safe and effective, with favorable short-term outcomes. This technique can be used widely in clinical practice.

Panaxynol, a natural Hsp90 inhibitor, effectively targets both lung cancer stem and non-stem cells

Le, Huong Thuy,Nguyen, Huy Truong,Min, Hye-Young,Hyun, Seung Yeob,Kwon, Soonbum,Lee, Yeongcheol,Le, Thi Hong Van,Lee, Jeeyeon,Park, Jeong Hill,Lee, Ho-Young Elsevier 2018 Cancer letters Vol.412 No.-

<P><B>Abstract</B></P> <P>Cancer stem-like cells (CSCs) contribute to tumor recurrence and chemoresistance. Hence, strategies targeting CSCs are crucial for effective anticancer therapies. Here, we demonstrate the capacities of the non-saponin fraction of <I>Panax ginseng</I> and its active principle panaxynol to inhibit Hsp90 function and viability of both non-CSC and CSC populations of NSCLC <I>in vitro</I> and <I>in vivo.</I> Panaxynol inhibited the sphere forming ability of NSCLC CSCs at nanomolar concentrations, and micromolar concentrations of panaxynol suppressed the viability of NSCLC cells (non-CSCs) and their sublines carrying acquired chemoresistance with minimal effect on normal cells derived from various organs. Orally administered panaxynol significantly reduced lung tumorigenesis in <I>Kras</I> <SUP> <I>G12D/+</I> </SUP> transgenic mice and mice carrying NSCLC xenografts without detectable toxicity. Mechanistically, panaxynol disrupted Hsp90 function by binding to the N-terminal and C-terminal ATP-binding pockets of Hsp90 without increasing Hsp70 expression. These data suggest the potential of panaxynol as a natural Hsp90 inhibitor targeting both the N-terminal and C-terminal of Hsp90 with limited toxicities.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Panaxynol inhibited the sphere-forming ability of NSCLC CSCs by inducing apoptosis. </LI> <LI> Panaxynol suppressed the viability of NSCLC cells with no effects on normal cells. </LI> <LI> Panaxynol significantly reduced lung tumorigenesis without detectable toxicity. </LI> <LI> Panaxynol interacted with the N- and C-terminal ATP binding pockets of Hsp90. </LI> <LI> Panaxynol disrupted Hsp90 function without inducing Hsp70 expression. </LI> </UL> </P>