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21.
Ho Van Doanh Phan Bao Quoc Hieu Pham Ngoc Son Dao Van Hoang Tam Hoang Duc Ho Manh Dung 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1361-1365
Journal of Radioanalytical and Nuclear Chemistry - To keep the accredited category for the gamma spectrometry test in our laboratory, the efficiency curves of a HPGe detector for soil sample in... 相似文献
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Abstract Elevated plasma cholesterol is now well established as a major risk factor for cardiovascular diseases. It has also been shown that the oxidation of low density lipoproteins leads to the formation of foam cells which contribute to the deposition of cholesterol in arteries. 相似文献
24.
Huu-Hung Nguyen Thi-Phuong Nguyen Nguyen Tien Trung Cam-Tu D. Phan Thi-Bich-Ngoc Dao Dinh-Tri Mai Jirapast Sichaem Ngoc-Hong Nguyen Cong-Luan Tran Thuc-Huy Duong 《Arabian Journal of Chemistry》2021,14(7):103189
Two new cycloartanes, combretanones G and H (1 and 2), were isolated from the leaves of Combretum quadrangulare. Their structures were elucidated by applying a set of spectroscopic methods, while their relative configurations were determined using DFT-NMR chemical shift calculations and subsequent assignment of DP4 probabilities. Compounds 1 and 2 are C-23/C-24 stereoisomers of the previously-reported euphonerin E. Both exhibited moderate cytotoxicity against three human cancer cell lines. Compound 2 was shown to be a potent antiparasitic. Our results confirm the traditional medicinal uses of Combretum quadrangulare in Vietnam. 相似文献
25.
Dr. Guangwu Li Prof. Taisuke Matsuno Yi Han Dr. Hoa Phan Shaofei Wu Dr. Qing Jiang Ya Zou Prof. Hiroyuki Isobe Prof. Jishan Wu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9814-9822
Synthesis of fully conjugated cyclophanes containing large-size polycyclic aromatics is challenging. Now, three benzidine-linked, hexa-peri-hexabenzocoronene (superbenzene)-based ortho-, para-, and meta-cyclophanes are synthesized through intermolecular Yamamoto coupling reaction of structurally pre-organized precursors. Subsequent oxidative dehydrogenation gave the corresponding quinoidal benzidine-linked cyclophanes. Their geometries were confirmed by X-ray crystallographic analysis and their electronic properties were investigated by electronic absorption, cyclic voltammetry, and DFT calculations. The quinoidal benzidine-linked cyclophanes show thermally populated paramagnetic activity with a relatively large singlet-triplet energy gap. Two enantiomers for the ortho-cyclophanes ( 1-NH and 1-N ) were isolated and their chiral figure-of-eight macrocyclic structures were identified. The cage-like cyclophanes 2-NH and 3-NH with concave surface can selectively encapsulate fullerene C70. 相似文献
26.
Adam Ashcraft Kaixuan Liu Arindam Mukhopadhyay Victor Paulino Chuan Liu Brianna Bernard Dalia Husainy Tina Phan Jean‐Hubert Olivier 《Angewandte Chemie (International ed. in English)》2020,59(19):7487-7493
Locking‐in the conformation of supramolecular assemblies provides a new avenue to regulate the (opto)electronic properties of robust nanoscale objects. In the present contribution, we show that the covalent tethering of a perylene bisimide (PBI)‐derived supramolecular polymer with a molecular locker enables the formation of a locked superstructure equipped with emergent structure–function relationships. Experiments that exploit variable‐temperature ground‐state electronic absorption spectroscopy unambiguously demonstrate that the excitonic coupling between nearest neighboring units in the tethered superstructure is preserved at a temperature (371 K) where the pristine, non‐covalent assembly exists exclusively in a molecularly dissolved state. A close examination of the solid‐state morphologies reveals that the locked superstructure engenders the formation of hierarchical 1D materials which are not achievable by unlocked assemblies. To complement these structural attributes, we further demonstrate that covalently tethering a supramolecular polymer built from PBI subunits enables the emergence of electronic properties not evidenced in non‐covalent assemblies. Using cyclic voltammetry experiments, the elucidation of the potentiometric properties of the locked superstructure reveals a 100‐mV stabilization of the conduction band energy when compared to that recorded for the non‐covalent assembly. 相似文献
27.
Guangwu Li Taisuke Matsuno Yi Han Hoa Phan Shaofei Wu Qing Jiang Ya Zou Hiroyuki Isobe Jishan Wu 《Angewandte Chemie (International ed. in English)》2020,59(24):9727-9735
Synthesis of fully conjugated cyclophanes containing large‐size polycyclic aromatics is challenging. Now, three benzidine‐linked, hexa‐peri‐hexabenzocoronene (superbenzene)‐based ortho‐, para‐, and meta‐cyclophanes are synthesized through intermolecular Yamamoto coupling reaction of structurally pre‐organized precursors. Subsequent oxidative dehydrogenation gave the corresponding quinoidal benzidine‐linked cyclophanes. Their geometries were confirmed by X‐ray crystallographic analysis and their electronic properties were investigated by electronic absorption, cyclic voltammetry, and DFT calculations. The quinoidal benzidine‐linked cyclophanes show thermally populated paramagnetic activity with a relatively large singlet‐triplet energy gap. Two enantiomers for the ortho‐cyclophanes ( 1‐NH and 1‐N ) were isolated and their chiral figure‐of‐eight macrocyclic structures were identified. The cage‐like cyclophanes 2‐NH and 3‐NH with concave surface can selectively encapsulate fullerene C70. 相似文献
28.
Quach Thi Thanh Van Le Thi Vien Tran Thi Hong Hanh Phan Thi Thanh Huong Nguyen The Cuong Nguyen Phuong Thao 《Natural product research》2020,34(9):1276-1281
AbstractUsing various chromatographic separations, three new acylated flavonoid glycosides, namely barringosides G–I (1–3), were isolated from the water-soluble extract of Barringtonia racemosa branches and leaves. The structure elucidation was performed by extensive analysis of the 1D and 2D NMR and HR-QTOF-MS data. Of the isolated compounds, barringoside I (3) showed moderate inhibitory effects on LPS-induced NO production in RAW264.7 cells with an IC50 of 52.48?±?1.04?µM. 相似文献
29.
Cong Nguyen Dinh Duc Luu Hoang Hong Phan Thanh 《Journal of Dynamics and Differential Equations》2022,34(1):605-636
We study the asymptotic dynamics of stochastic Young differential delay equations under the regular assumptions on Lipschitz continuity of the coefficient functions. Our main results show that, if there is a linear part in the drift term which has no delay factor and has eigenvalues of negative real parts, then the generated random dynamical system possesses a random pullback attractor provided that the Lipschitz coefficients of the remaining parts are small.
相似文献30.
Calculation of regulating index r from M̄W values determined by experiments is proposed. The calculation is based on the assumption that the M̄W values only depend on the conversion and the regulating index in emulsion polymerization. On this basis the calculation of regulator concentration in the latex particles was also possible. M̄W values calculated in this way and experimental M̄W values show good agreement. 相似文献