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51.
Thai Doan Chuong 《Journal of Mathematical Analysis and Applications》2012,388(1):443-450
This paper is concerned with the lower semi-continuity of the efficient (Pareto) solution map for the perturbed quasiconvex semi-infinite vector optimization problem (QCSVO). We establish sufficient conditions for the lower semi-continuous property of the efficient solution map of (QCSVO) under functional perturbations of both the objective function and the constraints. Examples are designed to analyze the obtained results. 相似文献
52.
Khang H. Trinh Phuong H. Tran Thanh T. Nguyen Son H. Doan Minh-Vien Le Tung T. Nguyen Nam T.S. Phan 《应用有机金属化学》2020,34(4):e5515
A strontium-doped lanthanum cobaltite perovskite, La0.6Sr0.4CoO3, was prepared and utilized as a recyclable heterogeneous catalyst for the direct oxidative C(sp3)─H/C(sp2)─H coupling reaction between cyclic ethers and alkenes or coumarins to achieve corresponding α-functionalized ethers. The α-functionalization of cyclic thioethers or amides with alkenes or coumarins was also achieved via this protocol. The La0.6Sr0.4CoO3 catalyst exhibited better performance than a variety of homogeneous and heterogeneous catalysts. Utilizing a recyclable catalyst would offer a greener option for the direct oxidative C(sp3)─H/C(sp2)─H coupling reaction. To our best knowledge, the C(sp3)─H/C(sp2)─H coupling between olefins and ethers to generate α-functionalized ethers using a heterogeneous catalyst has not been previously reported, and the α-functionalization of cyclic thioethers or amides with alkenes or coumarins is new. 相似文献
53.
Tan Ngo Hai Khoa Dao T. Loan Doan Thi 《The European Physical Journal A - Hadrons and Nuclei》2021,57(4):1-23
The European Physical Journal A - In recent years there has been much progress on the investigation of the QCD phase diagram with lattice QCD simulations. In this review we focus on the... 相似文献
54.
Christopher M. Hoo Trang Doan Natasha Starostin Paul E. West Martha L. Mecartney 《Journal of nanoparticle research》2010,12(3):939-949
Optimal deposition procedures are determined for nanoparticle size characterization by atomic force microscopy (AFM). Accurate
nanoparticle size distribution analysis with AFM requires non-agglomerated nanoparticles on a flat substrate. The deposition
of polystyrene (100 nm), silica (300 and 100 nm), gold (100 nm), and CdSe quantum dot (2–5 nm) nanoparticles by spin coating
was optimized for size distribution measurements by AFM. Factors influencing deposition include spin speed, concentration,
solvent, and pH. A comparison using spin coating, static evaporation, and a new fluid cell deposition method for depositing
nanoparticles is also made. The fluid cell allows for a more uniform and higher density deposition of nanoparticles on a substrate
at laminar flow rates, making nanoparticle size analysis via AFM more efficient and also offers the potential for nanoparticle
analysis in liquid environments. 相似文献
55.
The limiting swelling of a polyurethane of well defined structure was investigated in numerous solvents. It was found that the polymer dissolved for a very narrow range of solubility parameter (δ) values. The swelling in various solvent mixtures exhibits a sharp maximum for δ = 9.6±0.2. This value is suggested for δ of the polyurethane. Theoretical evaluations lead to a similar result. It was also found that for N-vinylpyrrolidone, a solvent for the polyurethane, δ is between 9.5 and 11.1. 相似文献
56.
Palmer R.A. Doan T.M. Lloyd P.G. Jarvis B.L. Ahmed N.U. 《Plasma Chemistry and Plasma Processing》2002,22(3):335-350
Experiments were performed in a thermal plasma furnace to examine the reduction of TiO2 by hydrogen plasma. The plasma gas composition was 50% hydrogen–50% argon, the plasma torch input power was 13 kW, the TiO2 initial mass was 10 g and the processing time was varied from 10 to 90 min. The reaction product contained between 67% and 73% titanium by mass for all tests. This level of reduction was consistent with chemical equilibrium modeling. There was no detectable enhancement of reduction due to the presence of atomic hydrogen. The Ti-O microstructures produced were characterized using quantitative SEM analysis. The microstructures showed a number of similarities with structures described by previous researchers. 相似文献
57.
Doan SC Shanmugham S Aston DE McHale JL 《Journal of the American Chemical Society》2005,127(16):5885-5892
Atomic force microscopy (AFM) of porphyrin aggregates formed on silica from acidic aqueous solution is used to investigate the basis for the previously reported counterion dependence of the optical spectra of aggregates of H(2)TCPP(2+), the diacid form of tetra(p-carboxyphenyl)porphyrin (TCPP). Resonance light scattering confirms the presence of excitonically coupled porphyrin aggregates in solutions of H(2)TCPP(2+) in both aqueous HCl and HNO(3). Aggregates formed in aqueous HNO(3) solutions show resonance light scattering (RLS) at wavelengths within both the H and J aggregate absorption bands and are imaged on the surface of silica as nanorods about 3 to 4 nm in height. H(2)TCPP(2+) aggregates in aqueous HCl solution exhibit RLS when excited within the blue-shifted Soret band (H band) and produce AFM images on silica of ring-shaped structures ranging from about 200 to 2000 nm in diameter. Fluorescence excitation and emission spectra reveal quenching of the Q-band emission in the aggregates at a pH less than 1 and confirm the existence of a single species, assigned to a dimer, at a pH just above 1. The morphology of the nanostructures as revealed by AFM provides insight into the structural basis for the counterion-dependent optical properties of H(2)TCPP(2+) aggregates. 相似文献
58.
Doan Thi Mai H Gaslonde T Michel S Koch M Tillequin F Pfeiffer B Renard P Kraus-Berthier L Léonce S Pierré A 《Chemical & pharmaceutical bulletin》2004,52(3):293-297
A series of cis-1,2-dihydroxy-1,2-dihydrobenzo[b]acronycine diacid hemiesters and dicarbamates were prepared by acylation of cis-1,2-dihydroxy-6-methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2-h]acridin-7-one. The cytotoxicity of the dicarbamates depended on the steric hindrance of the esterifying groups at positions 1 and 2. Diacid hemiesters displayed significant in vitro cytotoxic activities and induced cell cycle perturbations similar to those obtained with cis-1,2-diacetoxy-1,2-dihydrobenzo[b]acronycine (S23906-1) currently under preclinical development. cis-1-Acetoxy-2-hemiglutaryloxy-1,2-dihydrobenzo[b]acronycine was the most promizing compound of the series, inducing complete inhibition of tumor growth when tested against C38 colon adenocarcinoma implanted in mice. 相似文献
59.
Huong Doan Thi Mai Thang Pham Toan Giap Tran Huu Vu Thi Kim Oanh Nguyen Thi Minh Hang 《Natural product research》2020,34(19):2772-2778
AbstractTwo new prenylated flavonoids, 4´-methyl-8-prenyltaxifolin (1) and 6,8-diprenyl-4´-methyl-naringenin (2) and a new geranylated stilbene, 4′-deprenyl-4-methoxymappain (3) together with eight known flavonoids (4–11) were isolated from the fruits of Macaranga balansae Gagnep. Their chemical structures were determined by means of spectroscopic methods including 1D, 2D NMR, and MS data. Compound 2 showed the highest cytotoxic activity against PanC1, A549, KB and LU-1 cell lines with IC50 values range from 7.89 to 22.81?µM. 相似文献