An effective combination of reusable Pd@MOF catalyst and deep eutectic solvents for high-performance C–C coupling reaction

Minh-Huy Dinh Dang,Trang Thi Thu Nguyen,Bao Quang Gia Le,Linh Ho Thuy Nguyen,Ngoc Xuan Dat Mai,My Van Nguyen,Phuong Hoang Tran,Tan Le Hoang Doan 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.111 No.-

Pd-incorporated Zr-based metal–organic framework containing sulfone groups, named Pd(II)BUT-11, wassuccessfully prepared by dispersing the sulfone-functionalized MOF in Pd(OAc)2 solution. X-ray diffraction,scanning electron microscopy, N2 isotherm sorption, X-ray photoelectron spectroscopy, and thermogravimetricanalysis were applied to determine the features of the Pd-incorporated MOF. In the catalyticstudies, Pd(II)@BUT-11 was shown to be an efficient heterogeneous catalyst for synthesizing various stilbenederivatives via the cross-coupling Heck reaction with DABCO-derived deep eutectic solvent (DES) asa green solvent. Notably, the catalyst and the solvent could be recovered and reused, with their activityand structure remaining stable throughout several trials. The method provides an alternative solution tothe conventional catalysts and solvents, resulting in a green and efficient stilbene synthesis process. Furthermore, the stilbenes were separated by extraction with ethyl acetate due to the low solubility ofDES with this solvent.

Using sulfate-functionalized Hf-based metal–organic frameworks as a heterogeneous catalyst for solvent-free synthesis of pyrimido[1,2-a] benzimidazoles via one-pot three-component reaction

Minh-Huy Dinh Dang,Linh Ho Thuy Nguyen,Trang Thi Thu Nguyen,Ngoc Xuan Dat Mai,Phuong Hoang Tran,Tan Le Hoang Doan 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Functionalized metal–organic frameworks have recently received significant attention in heterogeneouscatalysis applications due to their high catalytic activity. In this work, a sulfate-functionalized Hf-clusterbasedmetal–organic framework was prepared via sulfation of a Hf-MOF, named Hf-BTC, constructed byHf6 clusters and 1,3,5-tricarboxylate linkers. The Hf-BTC-SO4 material was consequently demonstrated tobe an efficiently reusable superacid catalyst for a one-pot three-component reaction of pyrimido[1,2-a]benzimidazoles synthesis. The reaction catalyzed by the sulfated Hf-BTC could be carried out under mildand solvent-free conditions and give superior performance in a wide range of substrates. According todetailed investigation, the good catalytic performance of the sulfated-functionalized MOF likely originatesfrom the high-porosity framework and the high active sites of the functionalized clusters. Importantly, the catalyst could be easy to recover and reuse the functionalized framework several timeswith minor changes in catalytic efficiency.

Appropriation of Protocol for Laparoscopic Pancreaticoduodenectomy in Treatment of Periampullary Cancer

( Minh Hai Pham ),( Quan Anh Tuan Le ),( Hoang Bac Nguyen ),( Quang Hung Vu ),( Thai Ngoc Huy Tran ),( Hang Dang Khoa N Guyen ),( Thi Ngoc Sang Duong ),( Van Toan Tran ) 대한간학회 2020 춘·추계 학술대회 (KASL) Vol.2020 No.1

Aims: Laparoscopic pancreaticoduodenectomy (LPD) is considered as a safe and effective procedure in well - selected patients and appropriate surgical technique. Our aim is to evaluate suitability of using protocol for LPD in treatment of periampullary cancer at a single team. Methods: case series Results: Indication for LPD included 37 cases with resectable tumors which were classified basing on NCCN. All witness evaluation risk of complications with PREPARE score, ASA and evaluation risk of postoperative pancreatic fistula (POPF) with FRS classification. There were 2 open conversions because of vein resections, accounting for 5.4%. Standard lymphadenectomy was performed in all of 37 cases. In term of PREPARE score, major complications (Clavien - Dindo >= III) were 17.8%, 0% and 0% (5/28, 0/5 and 0/2 cases) in low risk, intermediate risk and high risk group, respectively. All of cases had ASA I or II. POPF happened 11.1% (1/9), 4.1% (1/24) and 50% (1/2) in low risk, intermediate risk and high risk group, respectively. Frozen section was needed for R0 margin. Retrieved lymph nodes was 8 - 18 with 12 lymph nodes in average. Conclusions: Indication for LPD with resectable tumors is acceptable. ASA I or II is a safe measure to select patient for LPD. FRS classification shows appropriation to evaluate risk of POPF.

The Effects of Online Social Influencers on Purchasing Behavior of Generation Z: An Empirical Study in Vietnam

Minh PHAM,Thao Yen DANG,Thi Hong Yen HOANG,Thi Thanh Nga TRAN,Thi Huong Quynh NGO 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.11

The purpose of this study is to understand the impact of influencers on generation Z (Gen Z) in the online environment. This article has applied the theories of source credibility, TAM, IAM, and TPB to identify influencer characteristics that affect the purchasing behaviors of Gen Z customers. This research was conducted using a Google Form survey with 24 pre-designed questions. A total of 464 valid questionnaires from Gen Z Vietnamese were collected between November 2020 and January 2021. Data was analyzed using partial least squares structural equation modeling (PLS-SEM) with SmartPLS 3 software. The analysis results confirmed that the components of influencer credibility have a positive impact on Gen Z’s purchasing behaviors under the mediated influence of argument quality, perceived usefulness, and social influence. Surprisingly, for Gen Z, the influencers’ attractiveness has the strongest impact on their online behavior. More specifically, attractiveness plays the most important role in the perceived usefulness and social influence of Gen Z customers, while influencers’ expertise has the strongest impact on argument quality delivered to customers. This study provides evidence of a change in the way Gen Z responds to marketing activities. They are more drawn by the attraction of influencers than their expertise.

Optimization-Based Fuzzy Energy Management Strategy for PEM Fuel Cell/Battery/Supercapacitor Hybrid Construction Excavator

Hoang Vu Dao,Xuan Dinh To,Hoai Vu Anh Truong,Tri-Cuong Do,Cong Minh Ho,Tri Dung Dang,안경관 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.4

Fuel cell hybrid electric construction equipment (FCHECE) is known as a promising solution to achieve the goal of energy saving and environment protection. Energy management strategy is a key technology of FCHECE, which splits the energy fl ow between power sources. This paper presents a novel optimal energy management strategy for a hybrid electric-powered hydraulic excavator system to enhance power performance, power sources lifespan, and fuel economy. As for the proposed powertrain configuration, fuel cell serves as a primary energy source, and supercapacitor and battery are considered as energy storages. The integration of supercapacitor and battery in fuel cell vehicle has advantages of improving power performance and storing the regenerative energy for future usage. An energy management strategy based on fuzzy logic control and a rule-based algorithm is proposed to effectively distribute the power between the three sources and reuse the regenerative energy. Furthermore, the parameters of the fuzzy logic system are optimized using the combination of a backtracking search algorithm which provides a good direction to the global optimal region and sequential dynamic programming as a local search method to fi ne-tune the optimal solution in order to reduce the hydrogen consumption and prolong the lifetime of the power sources. Simulation results show that the proposed energy management strategy enhances the vehicle performance, improves fuel economy of the FCHECE by 10.919%, increase battery and supercapacitor charge-sustaining capability as well as efficiency of the fuel cell system.

Morphological and Molecular Identification of Pseudo-nitzschia sp. Strain G3 Isolated from Northern Coast of Vietnam Based on ITS Region Sequences

Dang, Diem-Hong,Luyen, Hai-Quoc,Hien, Hoang Thi Minh,Thu, Ngo Hoai,Anh, Hoang Lan The Korean Society for Marine Biotechnology 2007 한국해양바이오학회지 Vol.2 No.1

For the first time in Vietnam, morphological and molecular studies of a species belonging to Bacillariophyceae collected in Northern coast of Vietnam are presented. Observations with microscope showed that this species belong to genus: Pseudo-nitzschia and seem like P. pungens. Sequence data from the partial 18S small subunit ribosomal RNA gene (18S rDNA) and the internal transcribed spacer 1 - 5.8S - internal transcribed 2 have been used to determine clearly and generate a phylogenetic framework of the obtained sequences to previously reported sequences in GenBank. These results allowed us to highlight described species of Bacillariophyceae in Northern coast of Vietnam. Furthermore, accumulation of molecular study would be helpful for the identification of scientific name of harmful algal species and further taxonomic studies in Vietnam.

Design, Modeling and Analysis of a PEM Fuel Cell Excavator with Supercapacitor/Battery Hybrid Power Source

Dang, Tri Dung,Do, Tri Cuong,Truong, Hoai Vu Anh,Ho, Cong Minh,Dao, Hoang Vu,Xiao, Yu Ying,Jeong, EunJin,Ahn, Kyoung Kwan The Korean Society for Fluid Power and Constructio 2019 드라이브·컨트롤 Vol.16 No.1

The objective of this study was to design and model the PEM fuel cell excavator with supercapacitor/battery hybrid power source to increase efficiency as well as eliminate greenhouse gas emission. With this configuration, the system can get rid of the internal combustion engine, which has a low efficiency and high emission. For the analysis and simulation, the governing equations of the PEM system, the supercapacitor and battery were derived. These simulations were performed in MATLAB/Simulink environment. The hydraulic modeling of the excavator was also presented, and its model implemented in AMESim and studied. The whole system model was built in a co-simulation environment, which is a combination of MATLAB/Simulink and AMESim software. The simulation results were presented to show the performance of the system.

The complete chloroplast genome of Syzygium polyanthum (Wight) Walp. (Myrtales: Myrtaceae)

Hoang Danh Nguyen,Minh Thiet Vu,Hoang Dang Khoa Do 국립중앙과학관 2023 Journal of Asia-Pacific Biodiversity Vol.16 No.2

Syzygium polyanthum (Wight) Walp. is a common herbal medicine and food ingredient in South EastAsia. In this work, the chloroplast genome of S. polyanthum was sequenced and characterized using anext-generation sequencing method. The results revealed a quadripartite chloroplast genome of158,535 bp in length, including a large single-copy region, a small single-copy region, and two invertedrepeat regions of 87,759 bp, 18,708 bp, and 26,034 bp in size, respectively. This genome contained 124genes (with 17 duplicated genes in inverted repeat regions), including 79 protein-coding genes, eightribosomal RNAs, and 37 transfer RNAs. Based on the chloroplast genomes of 47 Myrtaceae species, aphylogenetic analysis revealed that the Syzygium genus was divided into three clades, in whichS. polyanthum was a sister to a clade formed by S. malaccense, S. samarangense, S. aromaticum, S. rehderrianum, and S. nervosum. This study reports the first record of a complete chloroplast ofS. polyanthum that provides useful genetic information for further studies on taxonomy, genomicstructural variation, and the evolution of Syzygium as well as the Myrtaceae family.

Establish Cultivation by Mixing Crops of Different Strains of Eucheuma and Kappaphycus Species

Dang, Diem Hong,Hoang, Minh Hien,Ngo, Thi Hoai Thu,Dinh, Thi Thu Hang,Huynh, Quang Nang The Korean Society for Marine Biotechnology 2010 한국해양바이오학회지 Vol.4 No.1

Species Kappaphycus alvarezii (Doty) Doty, Kappaphycus striatum (Schmitz.) Doty and Eucheuma denticulatum (N. L. Burman) Collins et Harvey, which was brought to Vietnam from Japan in 1993 and Coco island, Martan Sea, Cebu, Philippines in 2005 have been cultivated in the different coasts of South Central Vietnam. Their growth rates and physical properties of carrageenan, then, were analyzed. The obtained results showed that the growth rate of E. denticulatum and K. striatum strains is higher than those of K. alvarezii. Species of K. striatum could grow over wide range of temperature and tolerate more strongly to high temperature compared with K. alvarezii, but their content and gel strength of kappa-carrageenan were almost the same and high. For purpose of the Kappahycus cultivation farms with stable and high production all year round (especially in the seawaters of shallow, semi-closed Lagoons where the water movement is not good and with high temperature in the hot season), mixed cropping of K. alvarezii and K. striatum as seeds stock during different cropping seasons was established. Our results suggested that K. alvarezii and K. striatum could be grown in the cool season (from Oct. to next March) with the same and high content and gel strength of kappa - carrageenan, but in the hot season need to chose K. striatum for cultivation only (from Apr. to Sept.).

Effects of non-vertical linear motions of a hemispherical-float wave energy converter

Do, Hoang-Thinh,Dinh, Quang-Truong,Nguyen, Minh-Tri,Phan, Cong-Binh,Dang, Tri-Dung,Lee, Seyoung,Park, Hyung-Gyu,Ahn, Kyoung-Kwan Elsevier 2015 Ocean engineering Vol.109 No.-

<P><B>Abstract</B></P> <P>The hydraulic power-take-off mechanism (HPTO) is one of the most popular methods in wave energy converter (WECs). However, the conventional HPTO with only one direction motion has some drawbacks which limit its power capture capability. This paper proposes an <I>adjustable slope angle wave energy converter</I> (ASAWEC) and investigates the effect of slope angle on the performance of the proposed wave energy converter to find the optimal slope angle with the purpose to increase the power capture capability as well as energy efficiency. A mathematical model of components from a floating buoy to a hydraulic motor was modeled. A small scale WEC test rig was fabricated to verify the power capture capability and efficiency of the proposed system throughout experiments.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper proposed an adjustable moving angle wave energy converter (AMAWEC). </LI> <LI> Mathematical model of AMAWEC was presented and simulated. </LI> <LI> An AMAWEC test rig were fabricated to do the experiment in variety of wave conditions and moving angle in the water tank. </LI> <LI> The effect of moving angle on the performance of a wave energy converter was investigated to find the optimal moving angle in each wave condition. </LI> <LI> Finally, the effectiveness of AMAWEC has been verified by experimental results. </LI> </UL> </P>