bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrically conductive membrane based on epoxidized natural rubber‐graft‐polyaniline nanomatrix
Authors: Ha Nguyen Thu , Hieu Vu Huy , Nam Nguyen Hai , Nghia Phan Trung , Ougizawa Toshiaki , Kawahara Seiichi 
Published: March 2024

AbstractIn this study, electrically conductive membrane based on natural rubber was prepared through graft‐copolymerization of aniline on natural rubber, and epoxidation in latex stage. The structural characterization of the resulting material through NMR spectroscopy confirmed that polyaniline and epoxy group were successfully introduced to natural rubber chain. The polyaniline nanomatrix formed in materials was confirmed through TEM observation. The thermal properties, mechanical properties, electrical conductivity of the resulting material, i.e., epoxidized deproteinized natural rubber‐grafted‐polyaniline (EDPNR‐g‐PAni), were investigated in comparison with those of raw natural rubber. The obtained results indicated that tensile strength and thermal resistance of EDPNR‐g‐PAni were higher than that of the raw material. The electrical conductivity of EDPNR‐g‐PAni was 6.86 × 10‐4 S/cm, which was remarkably improved. This result was attributed to the synergistic effect of polyaniline nanomatrix and epoxy group in natural rubber.
Cytotoxic constituents from the stem barks of Ceriops decandra (Griff.) W. Theob.
Authors: Linh Kieu Thi Phuong , Binh Pham Thanh , Van Chien Nguyen , Trung Nguyen Quoc , Thong Vu Huy , Van Thanh Nguyen , Thao Nguyen Phuong 
Published: March 2024

AbstractA phytochemical survey aiming to acquire pharmacologically active substances has resulted in the isolation of five dolabrane‐ (1–5), and ent‐pimarane‐type diterpenoids (6) were isolated from the methanol extract of C. decandra (Griff.) W. Theob. stem barks, via various chromatographic separations. Their structures were elucidated to be ent‐5α,3,15‐dioxodolabr‐1,4(18)‐diene‐2,16‐diol (1), tagalene I (2), ent‐5α,2,15‐dioxodolabr‐3‐ene‐3,16‐diol (3), tagalsin S (4), notolutesin H (5), and ent‐8,15R‐epoxypimaran‐16‐ol (6) by comprehensive analysis of spectroscopic data (1D, 2D NMR, and ESI‐MS data) as well as comparison with the previous literature. All of the isolates were evaluated for their cytotoxicity against human lung cancer (SK‐LU‐1), human hepatocellular carcinoma (HepG2), and human breast cancer (MCF‐7) cell lines. Compounds 2 and 6 exerted inhibitions toward three tumor cell lines (SK‐LU‐1, HepG2, and MCF‐7) with IC50 values between 5.63 and 11.70 μg/mL, while other compounds exhibited weak to moderate or no cytotoxic activities (IC50 > 20 μg/mL).
Synthesis of 1,1’‐diphenyl‐2‐thienyl‐2’‐(4‐substituted‐styryl)ethenes via oxidative Heck coupling reaction and photophysical studies
Authors: Thanh Le Tin , Hai Dang Xuan , Hien Nguyen , Hai Le Thi Hong , Thanh Le Thanh , Tung Dang Thanh 
Published: March 2024

AbstractIn this paper, we report the synthesis of four new 1,1’‐diphenyl‐2‐thienyl‐2’‐(4‐substituted‐styryl) ethenes via one‐step oxidative Heck coupling reaction of 1,1’‐diphenyl‐2,2’‐dithienylethene (DPDTE). This is a useful method to alkenylate DPDTE in order to enhance its fluorescence as well as its aggregation‐induced emission (AIE) properties. 1,1’‐Diphenyl‐2‐thienyl‐2’‐(4‐methylstyryl)ethene showed low fluorescent intensity in CHCl3 solution but very high AIE intensities. On the other hand, 1,1’‐diphenyl‐2‐thienyl‐2’‐(4‐acetoxystyryl)ethene showed both high fluorescence in CHCl3 solution and AIE intensities.
Low‐lying states of TaGe−/0/+ clusters from the CASPT2 and DMRG‐CASPT2 calculations
Authors: Van Tan Tran , Tri Tran Quoc , Thao Nguyen Minh , Mai Tran Thi Xuan , Hanh Nguyen Thi Hong 
Published: March 2024

AbstractThe low‐lying states of TaGe−/0/+ clusters have been investigated with the CASPT2 and DMRG‐CASPT2 methods. The DMRG‐CASPT2 method with an active space of 20 orbitals is expected to provide highly accurate relative energies of the electronic states. The leading configurations, bond distances, bond orders, vibrational frequencies, atomic charges, and relative energies of the electronic states are reported. The ground states of TaGe−/0/+ clusters are respectively predicted as the 3Δ, 4Φ, and 5Δ. The atomic charges of Ta in these ground states are more positive than those of the Ge atom. The electron detachment energies of the anionic and neutral clusters are estimated to be 1.62 and 6.84 eV. The Franck‐Condon factor simulations for the detachments of one electron from the anionic and neutral clusters exhibit extensively vibrational progressions because of the large structural difference between the initial and the final state.
Froth flotation process and its application
Authors: Mondal Sangita , Acharjee Animesh , Mandal Ujjwal , Saha Bidyut 
Published: March 2024

AbstractThe paper is about the froth flotation process and its application. It is a metallurgical process for the extraction of metals in a pure state from their ores: especially for sulfide ores. Froth flotation is one of the steps which is generally performed before roasting and it deals with the surface chemistry of liquids and of the minerals to be separated. This process requires a particular setup to be performed which contains different components. Surfactants play the most important role here. Different types of surfactants are used in different ways and each of them plays a crucial role like, collectors, frothers, froth stabilizers, depressants and activators, pH regulators etc. The sulfide ore flotation process can be studied by both chemical and electrochemical phenomena considering the interfacial energies. A broad application of this process in industrial field is the flotation of iron ores which is of two types: direct and reverse flotation. The later one is again based on two different types as cationic and anionic reverse flotation. In all these processes different types of flotation reagents are used. Another application is separation of malachite and azurite ore using sulfidization flotation.
Electrochemical determination of acetaminophen in pharmaceutical formulations and human urine using Ag‐Au bimetallic nanoparticles modified electrode
Authors: Phuong Ton Nu My , Diem Phan Nu Ha , Toan Tran Thanh Tam , Phong Nguyen Hai , Lieu Pham Khac , Son Le Van Thanh , Hoa Tran Thai , Khieu Dinh Quang 
Published: March 2024

AbstractIn the present paper, the Ag‐Au bimetallic nanoparticles (Ag‐AuNPs) was prepared by the simultaneous reduction of silver and gold with dextran solution. A novel glassy carbon electrode (GCE) modified by Ag‐AuNPs was employed for the voltammetric determination of acetaminophen (ACT). The nanoparticles were characterized by UV‐visible spectroscopy method which confirmed the homogeneous formation of the bimetallic alloy nanoparticles. Transmission electron microscopy (TEM) revealed that the synthesized bimetallic nanoparticles’ size was in the range of 20‐50 nm. The electrochemical behavior of ACT at the Ag‐AuNPs/GCE exhibited a higher electrocatalytic effect compared to that observed when GCE was modified with each constituent of the composite and bare GCE. A linear relationship between anodic current of ACT concentration was obtained over the range of 0.4 to 10.2 μM with a detection limit of 0.54 μM. The proposed method was simple, less time consuming and showed a high sensitivity. The application of this electrode to determine ACT in tablets and urine samples was proposed. The application of this electrode to determine ACT in tablets and urine samples was proposed. The results analyzed by the proposed method was not significantly different from that analyzed by standard HPLC method.
Spectroscopic (FTIR and UV), quantum Chemical, antifungal and antioxidant investigations of (E)‐7‐(4‐(trifluoromethyl)benzylidene)‐1,2,6,7‐tetrahydro‐8H‐indeno[5,4‐b]furan‐8‐one: A combined experimental and theoretical study
Authors: Adole Vishnu Ashok , More Rahul Ashokrao , Shinde Rahul Ashok , Dhonnar Sunil Laxman , Jagdale Bapu Sonu , Shinde Sachin Girdhar , Patil Arun Vitthal , Pawar Thansing Bhavsing 
Published: March 2024

AbstractIn the current study, we report the antifungal, antioxidant, and computational study of (E)‐7‐(4‐(trifluoromethyl)benzylidene)‐1,2,6,7‐tetrahydro‐8H‐indeno[5,4‐b]furan‐8‐one (FMBIF). The structure of the FMBIF was confirmed using spectroscopic techniques such as UV‐Vis, FT‐IR, 1H NMR, 13C NMR, and HRMS. Antifungal activity of the FMBIF was evaluated against four fungal strains namely Rhizopus oryzae, Mucor mucido, Aspergillus niger, and Candida albicans. The FMBIF was found to exhibit a good spectrum of antifungal activity against all the tested fungal strains. Additionally, it was also revealed to show good antioxidant potential. The Gaussian‐03 package was used to perform the density functional theory (DFT) calculations. The structural, chemical, UV‐Vis, and vibrational characteristics were evaluated using the DFT/B3LYP approach with a 6‐311++G(d,p) basis set. Using optimized molecular structure, the absorption wavelength, excitation energy, force strength, and electronic transitions were calculated using the TD‐DFT method with the CAM‐B3LYP functional and 6‐311++G(d,p) basis set. Mulliken atomic charges and molecular electrostatic potential surfaces are explored to investigate the electron density distribution in the titled compound. The DFT investigation's spectroscopic results were in good concurrence with experimental data.
Mg2+ embedded MIL‐101(Cr)‐NH2 framework for improved CO2 adsorption and CO2/N2 selectivity
Authors: Ky Vo The , Quang Duong Tuan 
Published: March 2024

AbstractThe development of a CO2‐selective adsorbent with high CO2 uptake capacity and CO2/N2 selectivity is a challenge. In this work, Mg2+‐embedded MIL‐101(Cr)‐NH2 frameworks (Mg@MCrN) were simply prepared via a facile one‐step synthesis. The results indicated that the incorporation of a proper amount of Mg2+ into the host MIL‐101(Cr)‐NH2 increased the porosity of the resultant adsorbent. Noticeably, the temperature‐programmed desorption of CO2 (TPD‐CO2) analysis revealed that the prepared Mg@MCrN contained new metal active sites along with coordinately unsaturated Cr(III) sites and amine (NH2) sites of the framework. At 100 kPa and 25 oC, the prepared Mg@MCrN‐0.2 exhibited the highest CO2 uptake capacity and CO2/N2 selectivity of ca. ~3.04 mmol.g‐1 and ca. ~ 60, respectively, surpassing the parent MOF and many other CO2 benchmark adsorbents. Moreover, the CO2 adsorption capacity over the Mg2+‐incorporated MIL‐101(Cr)‐NH2 remained even after 5 cycles of adsorption‐desorption under pressure swing from 0 to 100 kPa. This work opens a new perspective for developing efficient CO2‐selective materials.
Effects of bioactive substances to prolong the shelf‐life and inhibit the formation of black spots in black tiger shrimp (Penaeus monodon) preserved at 0 degree C
Authors: Tam Le Nhat , Anh Huynh Nguyen Que , Khue Doan Nhu , Uyen Phan Thuy Xuan , Thanh Nguyen Ba , Huong Nguyen Thi , Thien Van Hong , Van Hai Chu , Vu Truong Huynh Anh , Hung Nguyen Quoc 
Published: March 2024

AbstractThe objective of this study was to extend the shelf‐life and inhibit the process of black spots formation in giant black tiger shrimp (Penaeus monodon) by using 1.5 % solutions of the bioactives including: gallic acid, caffelic acid and cinnamaldehyde. Shrimp samples were dipped in the solutions for ten minutes, at 4°C and stored at 0°C for 15 days. Total viable count (TVC), melanosis evaluation method, chemical quality indexes including total volatile base nitrogen (TVB‐N), trimethylamine nitrogen (TMA‐N), pH and hypoxanthine values were used to evaluate the effectiveness of the treatments. TVC values, melanosis score of shrimp samples treated with bioactive compounds appeared more slowly, TVB‐N and TMA‐N values changed exponentially, hypoxanthine values increased linearly with storage time, and pH decreased on day 2, then increased gradually. Shelf life of treated samples were found to be longer than that of the control sample (8 days), and had a better ability to inhibit melanosis, in particular, the samples treated with a solution of cinnamaldehyde had the longest shelf life of 14 days, compared with 13 days of samples treated with caffelic acid and 12 days of the ones treated with gallic acid.
Synthesis of two indomethacin‐dimers with biological activity on heart failure
Authors: Lauro Figueroa‐Valverde , Francissco Diaz‐cedillo , Marcela Rosas‐Nexticapa , Maria López‐Ramos , Virginia Mateu‐Armad Maria , Magdalena Alvarez‐Ramirez , Tomas Lopez‐Gutierrez , Alejandra Garcimarrero‐Espino 
Published: March 2024

AbstractThere are few studies for the preparation of dimers with biological activity. In this research, two indomethacin dimers were prepared from indomethacin and characterized by NMR spectroscopic methods. Then, biological activity produced by indomethacin dimers were evaluated on heart failure using a biological model. The results indicate that protocols used for synthesis of indomethacin dimers do not require special conditions to give a good yielding. Other data showed that indomethacin dimers decrease heart failure. In conclusion, indomethacin dimers would be good candidates for treating of heart failure.
Survey on different polyphenol extraction methods from avocado seed (Persea americana Mill) and assay on their antioxidant and acute toxicity activities
Authors: Hue Ha Thi , Thai Nguyen Minh , Dao Phan Thi Anh 
Published: March 2024

AbstractA comprehensive investigation of extraction methods on the efficiency of the total polyphenol contents (TPC) and antioxidant activities for both avocado seed groups with and without removing antinutrients (signed as groups A and B) and assessing acute toxicity on the extraction products. The Soxhlet extraction showed the most effective method for producing an avocado seed extract possessing the highest TPC and strong antioxidant activities, followed by the maceration, hot extraction, and percolation extraction. Interestingly, it was found that antinutrients containing in the seed can reduce TPC. For instances, sample 4B (Soxhlet method) exhibited the largest TPC (189.67±3.58 mgGAE/g DW) and DPPH inhibitory activity (IC50 = 19.24±1.23 μg/mL), while those of the sample 2A (percolation method) were 68.95±3.79 mgGAE/g DW and 67.48±0.98 μg/mL, respectively. Additionally, sample 4B did not exhibit acute oral toxicity (Dmax = 21.05 g/kg mice weight), indicating a safe and high antioxidant activity of avocado seed extract for clinical applications. A high correlation analyzed by Pearson's correlation was found for the TPC to DPPH assay and ferric reducing/ antioxidant assay, showing their correlation parameters of ‐0.898 and 0.847 (p < 0.05), respectively.
Spectroscopic (UV and fluorescence), biological, DFT and molecular docking studies of 3,5‐diethyl‐2r,6c‐di(4‐fluorophenyl)piperidin‐4‐one picrate
Authors: Savithiri S. , Bharanidharan S. 
Published: March 2024

AbstractThe spectroscopic investigations of 3,5‐diethyl‐2r,6c‐di(4‐fluorophenyl)piperidin‐4‐one picrate (3,5‐DEDFPP) are evaluated by UV–Vis and fluorescence techniques. At the B3LYP/6‐311++G(d,p) level of theory, the DFT approach was utilized to optimize the molecular structure. The dipole moment, polarizability, and hyperpolarizability values are calculated at same level of theory. NBO analysis was used to calculate the hyperconjugative interaction energy (E(2)) and electron densities of donor (i) and acceptor (j) bonds. The molecule's energy gap was discovered using HOMO and LUMO calculation. The Mulliken atomic charges of the carbon, nitrogen and oxygen atoms were calculated and using at the same level. The thermodynamic properties of the title compound were calculated at different temperatures in gas phase. The 3,5‐DEDFPP's bacterial activity was evaluated against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Vibreo cholerae, and Pseudomonas aeruginosa, as well as fungal strains such as Candida albicans, Aspergillus niger, Aspergillus flavus, and Trichophyton rubrum. The interaction of the title compound to bind to a target protein was studied using molecular docking analysis.
Spectroscopic analysis, DFT studies and molecular docking of 2,3‐dichloro‐benzylidine‐(2‐trifluoromethyl‐phenol)‐amine
Authors: Mohammed Ameen K. K. , Hajam Towseef Ahmad , Syed Ali Padusha M. , Saleem H. , Sarathi D. Partha 
Published: March 2024

Abstract2,3‐dichloro‐benzylidine‐(2‐trifluoromethyl‐phenol)‐amine (2DBTP) has been synthesized and characterized by various spectroscopic techniques including FT‐IR, FT‐Raman, UV‐Vis and 1H, 13C NMR spectroscopy. The equilibrium geometry and harmonic vibrational frequencies were investigated by density functional theory (DFT) at B3LYP/6‐311++G(d,p) basis set. The vibrational wavenumber assignments were made on the basis of total energy distribution (TED) calculations using Veda 4 program. The harmonic wavenumbers calculated at DFT were in line with the experimental values. The non‐linear optical properties (NLO) were calculated. Stability of the molecule arises from hyperconjugative interactions and charge delocalization was analyzed by natural bond orbital (NBO) analysis. Molecular electrostatic potential (MEP), mulliken atomic charges were also calculated. The energy gap of the molecule was found by HOMO and LUMO calculation. TD‐DFT calculations have been carried out on the optimized geometry to further understand the electronic transitions in the UV‐Vis spectrum of the compound. In addition, the 1H and 13C NMR chemical shift values of 2DBTP in the ground state were also calculated using Gauge invariant atomic orbital (GIAO) method. The molecular docking solved the binding mode of 2XCT complex with the ligand. The investigated molecule revealed the inhibition activity of the ligand against anti‐bacterial protein topoisomerase DNA gyrase enzyme (PDB ID: 2XCT).
Fabrication of ultra‐thin alumina membranes utilizing waste aluminum cans
Authors: Anh Dang Hoang , Toan Ngo Quoc , Tung Pham Cao Thanh , Son Cu Thanh , Nguyen Hieu Pham Trung , Nguyen Hoang‐Duy 
Published: March 2024

AbstractWe report on utilizing waste aluminum cans for anodic aluminum oxide (AAO) membranes fabrication. Aluminum (Al) presents in the cans is about 97 % tested via inductively coupled plasma‐mass spectrometry. Synthesis process of the AAO membranes includes heat‐treatment and surface polishing of the waste Al sheets, first anodization, aluminum oxide layer removing, second anodization, aluminum substrate separating and pore‐widening. Thickness and morphology of the prepared AAO membranes are observed through a field emission scanning electron microscopy. By controlling the second anodization time, the AAO membranes possess ultra‐thin thickness in the range of ~60‐650 nm. The average pore densities ~1.2 × 1010 and ~ 3.0 × 1010 hole/cm2 of the AAO membranes are obtained at constant anodization voltage of 40 and 25 V, respectively. Hole diameter of the AAO membranes can be varied from 30 to 95 nm via managing the pore‐widening time. The ultra‐thin AAO membranes with order nano‐hole arrays can be used as hard‐templates which are promising for unique nanostructures synthesis at low cost and environment friendly.
A facile synthesis, characterization and docking studies of 2‐methyl‐3‐(5‐phenyl‐4H‐(1,2,4)triazol‐3‐yl)‐quinoxaline and its derivatives
Authors: Reddy S. Ramakrishna , Reddy G. Ganga , Reddy Ch. Venkata Ramana , Reddy B. Srinivasa , Laxminarayana E. 
Published: March 2024

AbstractA new series of 2‐Methyl‐3‐(5‐phenyl‐4H‐(1,2,4)triazol‐3‐yl)‐quinoxaline derivatives have been synthesized by simple and efficient method by using 3‐methyl‐quinoxaline‐2‐carboxylic acid, 3‐methyl‐quinoxaline‐2‐carboxylicacidethylester and 3‐methyl‐quinoxaline‐2‐carboxylichydrazide as reaction intermediates in good yields. All the synthesized compounds were characterized by spectral and elemental analysis. The molecular docking studies of 2‐Methyl‐3‐(5‐phenyl‐4H‐(1,2,4)triazol‐3‐yl)‐quinoxalinecarried to predict the anti bacterial potential.
The influence of technological conditions and molecular weight of PEG on basal spacing of Vietnamese bentonite
Authors: Thuy Nguyen Thi , Duc Vu Minh 
Published: March 2024

AbstractThe unique expansion properties of the interlayer space of montmorillonites allow for surface modification of bentonite. PEG is a nonionic polymer that can adsorb and intercalate into the interlayers of bentonite. The results of FTIR and TGA spectra allow confirming that PEG has not only covered bentonite but also inserted into the interlayers of bentonite. Therefore, the modified product can be applied not only as a dispersant in polymer composites, but also as an adsorbent. Moreover, a variety of technological factors affecting modification have been studied and the most suitable conditions have been proposed. In which, temperature, stirring speed, time and suspension concentration were selected at 25°C, 800 rpm, 8 h and 2 wt.%, respectively. The influence of the component ratio (Ben/PEG) on the modification process was also studied. The most suitable Ben/PEG ratio for each PEG type was also given. The results show that the interlayer spacing in modified bentonite depends not only on the technological conditions, the composition ratio but also on the molecular weight of PEG. Thus, the choice of PEG for bentonite modification will determine the d001 basal spacing of modified product.
Flavonoids as potential agents for development of multi‐target drugs for covid‐19 treatment: An in silico study
Authors: Hang Nguyen Thu , Van Phuong Nguyen 
Published: March 2024

AbstractCOVID‐19 is an infectious disease caused by SARS‐CoV‐2 that is spreading in many countries around the world. In attempts to discover compounds that have an effect on SARS‐CoV‐2, many important molecular targets have been identified, involved in viral infection and replication including spike protein, main protease, capthesin L, helicase, 2‐O‐methyltransferase, endoRNAse. In this study, we would like to identify pot ential flavonoids that could simultaneously inhibit 3CLP, capthesin L, endoRNAse, 2‐O‐methyltransferase, and PLP from a 4389‐flavonoid database using molecular docking, molecular dynamics simulation, pharmacokinetic and toxicity prediction. Out of 4389 compounds, 79 potential flavonoids that could simultaneously inhibit five COVID‐19 molecular targets were identified. Pharmacokinetic and toxicity prediction showed that these compounds were well absorbed from the gastrointestinal tract and safe for human use. These potential compounds were noteworthy during drug research and development for SARS‐CoV‐2 treatment.
Synthesis and cytotoxicity of nitrogen‐containing curcuminoids against cancer cell lines
Authors: Van Pham Thi Bich , Huy Nguyen Trong , Hao Hoang Minh 
Published: March 2024

AbstractIn a previous study, we performed the structural modification of the curcumin skeleton by varying substituents in phenyl rings. In continuation of that work, we now focus on the synthesis of nitrogen‐containing curcuminoids by a pyrazole cyclization between the free β‐diketone curcuminoids bearing ‐OCH3/‐OH/‐F substituents in aromatic rings and phenyl hydrazine hydrochloride. Seven N‐phenyl pyrazole curcuminoids (1a‐7a) were synthesized in yields of 39‐73 % and derivative (7a) was reported for the first time. Synthesized compounds were evaluated for their cytotoxicities against HepG2, LU‐1 and KB cancer cell lines. Compared to the pristine compound, i.e., curcumin, compound (1a) demonstrated better inhibitory activities toward three cell lines. Derivative (2a) exhibited higher anti‐cancer capacity against HepG2 and LU‐1 than curcumin. Analogues (4a‐7a) bearing pyrazole ring and ‐OCH3/‐F groups in aromatic rings displayed low/inactive anti‐cancer activities. In addition, compared to pyrazole curcumin (PC), derivative (1a) containing N‐phenyl substituent displayed lower cytotoxicities toward HepG2 and KB cell lines.