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91.
Daixing Wei Yiqing Wang Prof. Chung-Li Dong Ta Thi Thuy Nga Yuchuan Shi Jialin Wang Xiaoli Zhao Prof. Fan Dong Prof. Shaohua Shen 《Angewandte Chemie (International ed. in English)》2023,62(31):e202306876
Oxide-derived Cu (OD−Cu) featured with surface located sub-20 nm nanoparticles (NPs) created via surface structure reconstruction was developed for electrochemical CO2 reduction (ECO2RR). With surface adsorbed hydroxyls (OHad) identified during ECO2RR, it is realized that OHad, sterically confined and adsorbed at OD−Cu by surface located sub-20 nm NPs, should be determinative to the multi-carbon (C2) product selectivity. In situ spectral investigations and theoretical calculations reveal that OHad favors the adsorption of low-frequency *CO with weak C≡O bonds and strengthens the *CO binding at OD−Cu surface, promoting *CO dimerization and then selective C2 production. However, excessive OHad would inhibit selective C2 production by occupying active sites and facilitating competitive H2 evolution. In a flow cell, stable C2 production with high selectivity of ∼60 % at −200 mA cm−2 could be achieved over OD−Cu, with adsorption of OHad well steered in the fast flowing electrolyte. 相似文献
92.
Ai Doan Thi Thuy Van Trinh Thi Thanh Huong Doan Thi Mai Huyen Tram Le Marc Litaudon Van Minh Chau Van Cuong Pham 《Tetrahedron letters》2018,59(20):1909-1912
Two novel alkaloids, with an unprecedented carbon skeleton, pileamartines A (1) and B (2), together with the known alkaloid, julandine (I-a) were isolated from the alkaloidal fraction of Pilea aff. martinii leaves. Their structures were established by spectral data analysis, including MS and 2D NMR. The absolute configurations of 1 and 2 were suggested by comparison of their experimental and calculated electronic circular dichroism spectra. Compound 2 exhibited weak inhibitory activity against the α-glucosidase enzyme with an inhibition of 11% at a concentration of 200?µM. These compounds were not cytotoxic against several cancer cell lines even at a concentration of 150?µM. 相似文献
93.
Ai Doan Thi Thuy Ngan Truong Bich Hien Nguyen Thi Linh Nguyen Thuy Van Cuong Pham Huyen Vu Thi Huong Doan Thi Mai 《Chemistry of Natural Compounds》2021,57(2):360-363
Chemistry of Natural Compounds - 相似文献
94.
95.
V. P. Baryshok L. N. Thuy Zang M. G. Voronkov 《Russian Journal of General Chemistry》2013,83(8):1501-1502
A one-step method for the synthesis of 1-acyloxygermatranes RC(O)OGe(OCH2CH2)3N in the reaction of germanium dioxide with triethanolamine and a carboxylic acid was developed. 1-Acyloxygermatranes, including those containing biologically active acyloxy groups (R = 2-MeC6H4CH2OCH2, C6H5, 2-HOC6H4), were obtained with a 82–96.5% yield. 相似文献
96.
Thuy Trang NguyenThanh Cong Bach Huong Thao PhamThe Tan Pham Duc Tho NguyenNam Nhat Hoang 《Physica B: Condensed Matter》2011,406(19):3613-3621
The electronic structures of bulk, 2D slabs and clusters of CaMnO3 in various magnetic configurations are presented. The obtained results including optimized cell constant, band-gap, Mn magnetic moment, on-site Coulomb repulsion potential and p-d charge separation potential are in good agreement with experiment data. The energetically most preferable configuration was an insulating charge-transfer ground state with G-type antiferromagnetic (AF) configuration (classified according to Wollan and Koehler, Phys. Rev. 100 (1955) 545). For the finite 2D layers the C-type AF ground state was found to be most stable. The surface effect on magnetism of finite quasi 2D systems appeared to originate in the pyramidal field splitting of Mn 3d levels, which induced the formation of ferromagnetic (FM) regions within the AF matrix and the extension of FM correlation deep through 7 subsurface layers (2.7 nm from the surface). All finite systems (clusters and slabs) were found non-conducting due to the localization of electrons and the cancellation of surface excess carriers (holes) after surface relaxation, although the band-gaps of 2D systems were sufficiently reduced in comparison with that of the bulk. 相似文献
97.
98.
Development of a homogeneous immunoassay system using protein A fusion fragmented Renilla luciferase
A homogeneous immunoassay system was developed using fragmented Renilla luciferase (Rluc). The B domain of protein A was fused to two Rluc fragments. When complexes between an antibody and fragmented Rluc fusion proteins bind to target molecules, the Rluc fragments come into close proximity and the luminescence activity of fragmented Rluc is restored by complementation. As proof-of-principle, this fragmented Rluc system was used to detect E. coli homogeneously using an anti-E. coli antibody. 相似文献
99.
Tran Thi Thuy S. Hoste G. G. Herman K. De Buysser P. Lommens J. Feys D. Vandeput I. Van Driessche 《Journal of Sol-Gel Science and Technology》2009,52(1):124-133
A water based YBa2Cu3O7−x
(YBCO) precursor using a triethanolamine (TEA)/acetic acid complexing method to obtain YBCO thin films is described in detail.
The influence of complexation behavior in the formation of transparent and homogenous sols and gels after the combination
of Y, Ba and Cu—acetates, acetic acid and TEA has been studied by potentiometric titration and the results are compared with
analytical simulations. The decomposition of the gel was studied by IR (infrared) and Thermal Gravimetric Analysis/Differential
Thermal Analysis (TGA/DTA). The results in sol-gel chemistry can be used to decide on the necessities in the preparation of
stable sol–gel precursors with a minimum amount of organic compounds. The sol–gel system was also used for the deposition
of high textured superconducting thin films on STO substrates by dip coating. The synthesized YBCO showed a superconducting
transition temperature of 90.95 K with narrow ΔT (2 K) for thin films. The results from X-ray diffraction show that the single
phase YBCO was obtained. SEM pictures also indicate that the properties of the surface thin films are good. 相似文献
100.
Sang-Eun Kim Tran Thi Thanh Thuy Ji-Hyun Lee Jai Youl Ro Young-An Bae Yoon Kong Jee-Yin Ahn Dong-Soon Lee Yeon-Mock Oh Sang-Do Lee Yun-Song Lee 《Experimental & molecular medicine》2009,41(4):277-287
Matrix metalloproteinase-9 (MMP-9) may play an important role in emphysematous change in chronic obstructive pulmonary disease (COPD), one of the leading causes of mortality and morbidity worldwide. We previously reported that simvastatin, an inhibitor of HMG-CoA reductase, attenuates emphysematous change and MMP-9 induction in the lungs of rats exposed to cigarette smoke. However, it remained uncertain how cigarette smoke induced MMP-9 and how simvastatin inhibited cigarette smoke-induced MMP-9 expression in alveolar macrophages (AMs), a major source of MMP-9 in the lungs of COPD patients. Presently, we examined the related signaling for MMP-9 induction and the inhibitory mechanism of simvastatin on MMP-9 induction in AMs exposed to cigarette smoke extract (CSE). In isolated rat AMs, CSE induced MMP-9 expression and phosphorylation of ERK and Akt. A chemical inhibitor of MEK1/2 or PI3K reduced phosphorylation of ERK or Akt, respectively, and also inhibited CSE-mediated MMP-9 induction. Simvastatin reduced CSE-mediated MMP-9 induction, and simvastatin-mediated inhibition was reversed by farnesyl pyrophosphate (FPP) or geranylgeranyl pyrophosphate (GGPP). Similar to simvastatin, inhibition of FPP transferase or GGPP transferase suppressed CSE-mediated MMP-9 induction. Simvastatin attenuated CSE-mediated activation of RAS and phosphorylation of ERK, Akt, p65, IκB, and nuclear AP-1 or NF-κB activity. Taken together, these results suggest that simvastatin may inhibit CSE-mediated MMP-9 induction, primarily by blocking prenylation of RAS in the signaling pathways, in which Raf-MEK-ERK, PI3K/Akt, AP-1, and IκB-NF-κB are involved. 相似文献