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201.
Thang Nguyen Van Ba Vu Ngoc Thu Huynh Nguyen Phong Hao Le Cong Loan Truong Thi Hong 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):513-525
In this study, radioactivity of airborne particulate and rainwater samples were analysed during 2016 at three different sites in Ho Chi Minh City, Vietnam. The activities of gross alpha and gross beta measured in airborne particulate are in the range from (<?MDA-7.50) and (0.73–45.41) mBq m?3 respectively. In rainwater, theirs are in the range from (1.9–4.1) and (14.9–28.6) mBq l?1 respectively. Mean values of annual deposition fluxes of gross alpha and gross beta were found in the range from (5.56–10.65) and (50.9–70.5) Bq m?2 y?1 respectively. The correlation between radioactivity levels and meteorological factors are presented in this paper. 相似文献
202.
Melvyn Rowen Churchill Lynn M. Krajkowski My Hang Vo Huynh Kenneth J. Takeuchi 《Journal of chemical crystallography》1997,27(10):589-597
The complexcis-[Ru(bpy)2(PMe3)Cl+][ClO4 ?] crystallizes in space group P21/c andcis-[Ru(bpy)2{PMe2(o-tol)]Cl+][ClO4 ?] crystallizes in space group $P\bar 1$ ; each is present as a racemate and neither structure suffers from disorder. The Ru?PMe2(o-tol) bond length of 2.324(2)Å is slightly longer than the simple Ru?PMe3 bond length of 2.310(2) Å. 相似文献
203.
Melvyn Rowen Churchill Lynn M. Krajkowski My Hang Vo Huynh Kenneth J. Takeuchi 《Journal of chemical crystallography》1996,26(5):347-354
The complexcis-[Ru(bpy)2(PPh3)Cl+][ClO
4
–
] (where bpy=2,2-bipyridyl) crystallizes from a solution in toluene/dichloromethane as the toluene-hemi(dichloromethane) solvate in the centrosymmetric space group
witha=10.343(2)Å,b=11.823(3)Å,c=18.469(4)Å, =98.90(2)o, =93.32(2)o, =101.46(2)o,V=2177.8(8)Å3 andZ=2. The structure was refined toR(F)=4.6% for those 4248 reflections above 6(F
o
). The octahedral Ru(II) cation is associated with the bond lengths Ru–Cl=2.424(2)Å, Ru–PPh3=2.328(1) Å and Ru–N=2.045(5)–2.109(4)Å. Both the cation and the perchlorate anion are ordered. However, the unit cell also contains two disordered toluene molecules (centered about inversion centers at 1, 1/2, 0 and 1/2, 0, 1/2), and a disordered dichloromethane molecule of a partial occupancy (centered about 1/2, 0, 1). 相似文献
204.
Van Ngai Huynh Tron Nguyen Huu Van Vu Nguyen Théra Michel 《Journal of Optimization Theory and Applications》2022,193(1-3):180-218
Journal of Optimization Theory and Applications - Our aim in this article is to study the class of so-called $$\rho -$$ paraconvex multifunctions from a Banach space X into the subsets of another... 相似文献
205.
Nguyen Quoc Thai Ning-Hsuan Tseng Mui Thi Vu Tin Trung Nguyen Huynh Quang Linh Chin-Kun Hu Yun-Ru Chen Mai Suan Li 《Journal of computer-aided molecular design》2016,30(8):639-650
Combining Lipinski’s rule with the docking and steered molecular dynamics simulations and using the PubChem data base of about 1.4 million compounds, we have obtained DNA dyes Hoechst 34580 and Hoechst 33342 as top-leads for the Alzheimer’s disease. The binding properties of these ligands to amyloid beta (Aβ) fibril were thoroughly studied by in silico and in vitro experiments. Hoechst 34580 and Hoechst 33342 prefer to locate near hydrophobic regions with binding affinity mainly governed by the van der Waals interaction. By the Thioflavin T assay, it was found that the inhibition constant IC50 ≈ 0.86 and 0.68 μM for Hoechst 34580 and Hoechst 33342, respectively. This result qualitatively agrees with the binding free energy estimated using the molecular mechanic-Poisson Boltzmann surface area method and all-atom simulations with the AMBER-f99SB-ILDN force field and water model TIP3P. In addition, DNA dyes have the high capability to cross the blood brain barrier. Thus, both in silico and in vitro experiments have shown that Hoechst 34580 and 33342 are good candidates for treating the Alzheimer’s disease by inhibiting Aβ formation. 相似文献
206.
Gold(I) bis(N‐heterocyclic carbene) complexes: Metabolic stability,in vitro inhibition,and genotoxicity
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We report the profiling of the metabolic stability, normal cell inhibition, and genotoxicity of the two gold complexes [Au (iPr2‐bimy)2]PF6 ( 1 ) and [Au (Fpyr)(iPr2‐bimy)]PF6 ( 2 ), which show strong apoptotic activities in lung cancer cells. Liver microsomal tests revealed that the compounds have a relatively high half‐life compared to midazolam and do not suffer rapid metabolism and in vitro clearance. The cytotoxic potential of these compounds were also relatively weak in normal cells, with higher IC50 values compared to cancer cells, with a 2–60 times difference. The Ames test revealed that the compounds do not give rise to any mutations as well. Overall, the compounds showed stability in liver microsomes, specificity for cancer cells, and a lack of genotoxic potential. 相似文献
207.
Polymer coating of graphene oxide via reversible addition–fragmentation chain transfer mediated emulsion polymerization
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Vien T. Huynh Duc Nguyen Christopher H. Such Brian S. Hawkett 《Journal of polymer science. Part A, Polymer chemistry》2015,53(12):1413-1421
This work describes a versatile method to encapsulate graphene oxide (GO) with polymers using reversible addition‐fragmentation chain transfer (RAFT) mediated emulsion polymerization. A living low molecular weight anionic macro‐RAFT statistical copolymer of sodium styrene sulfonate, acrylic acid, and butyl acrylate (BA) was synthesized using 2‐{[(butylsulfanyl)carbonothioyl] sulfanyl} propanoic acid as the chain transfer agent. GO was dispersed in water by pretreating the surface with poly(allylamine hydrochloride) (PAH), before being stabilized by the addition of the anionic macro‐RAFT copolymer. PAH was used to facilitate the adsorption of the macro‐RAFT copolymer to the GO surface via electrostatic attraction between opposite charges. The dispersed GO sheets were encapsulated with polymer by the free radical emulsion polymerization of methyl methacrylate and BA under starved fed conditions. The polymer shells encapsulating the GO sheets were formed by the chain extension of the adsorbed living macro‐RAFT copolymer. TEM, SEM, FTIR, and AFM were used to confirm the presence of the polymer layer on the surface of the GO. The thickness of the polymer coating can be adjusted by controlling the amount of monomer fed into the system. Partial polymer coatings of the GO could be achieved by varying the amount of PAH. The encapsulated GO was found to be easily dispersed in both aqueous and organic solvents over a range of polarities. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1413–1421 相似文献
208.
O. Novák H. Tur?i?ová M. Smr? J. Huynh M. Pfeifer P. Straka 《Applied physics. B, Lasers and optics》2012,108(3):501-508
A two-stage optical parametric amplifier driven by a frequency-tripled beam from the high-energy iodine laser system SOFIA was built. This single-shot Optical Parametric Chirped Pulse-Amplification facility (OPCPA) and the system synchronizing the pump and signal pulses are described in detail. The chirped seed pulse of a Ti:sapphire oscillator running at the central wavelength of 800?nm is amplified in the two-stage (LBO and KDP) optical parametric amplifier over 108 times. The amplified spectral bandwidth of 68?nm corresponds to the pulse duration of 14?fs when a transform-limited pulse is assumed. This implies a compressed pulse of TW power. Systematic gain measurements reveal a good match with the theoretical predictions. Signal and idler beam fluence profiles are presented. The suitability of the iodine photo-dissociation laser as a pump source for the OPCPA technique is thus proved for the first time experimentally. A distinctive feature of the iodine laser is its very narrow gain bandwidth (<0.1?cm?1) and, therefore, the conventional chirped-pulse amplification technique does not lead to pulse durations at the femtosecond level. 相似文献
209.
210.
The polymer-bound catalyst 3a-e inserted some spacer ([-NHCO(CH2 10- n; n = 0,1,2,3,4) connecting the catalytic moiety [cyclo(-(S)-Phe-(S)-His)], [(S,S)-1] and 2% cross-linked Merrifield's polymer, have been prepared and their catalytic efficiency for the enantioselective hydrocyanation of 3-phenoxybenzaldehyde was studied. 相似文献