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471.
The aim of the study was to suppress the bitterness and improve the palatability of pediatric prednisolone powder (PP) by the addition of simple sucrose syrup (SS) and various beverages and foods. Bitterness suppression was evaluated using the human gustatory sensory test. The suppression of the bitterness and improvement of palatability of PP by addition of SS solutions was investigated using standard taste substances: sucrose for sweetness, tartaric acid for sourness, and sodium chloride as saltiness. Dilution with SS solutions of up to 50% (w/w) was successful in bitterness-suppression and improvement of palatability, but at 80% (w/w) SS, the palatability of the diluted solution was reduced. The kinematic viscosities of SS solutions were therefore evaluated using the Uberorde viscosity meter, to see whether the high viscosity of the more concentrated solutions was responsible for the reduced palatability. The kinematic viscosity of the 80% SS was 16.60 mm(2)/s. Judging from above information, the palatability might become worse when the kinematic viscosity of syrup exceeded 15 mm(2)/s. Finally, the ability of various beverages and foods with low viscosity to suppress the bitterness and improve the palatability of PP were examined. The additions of orange juice or a carbonated lemon drink to simple syrup solution were most effective in suppressing bitterness and improving palatability of PP.  相似文献   
472.
The excitation energy transfer from meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) to 3,3'-diethyl-2,2'-thiatricarbocyanine iodide (DTTCI) along the deoxyribonucleic acid (DNA) double strand was investigated by the steady-state absorption and fluorescence measurements and time-resolved fluorescence measurements. The steady-state fluorescence spectra showed that the near-infrared fluorescence of DTTCI was strongly enhanced up to 86 times due to the energy transfer from the excited TMPyP molecule in DNA buffer solution. Furthermore, we elucidated the mechanism of fluorescence quenching and enhancement by the direct observation of energy transfer using the time-resolved measurements. The fluorescence quenching of TMPyP chiefly consists of a static component due to the formation of complex and dynamic components due to the excitation energy transfer. In a heterogeneous one-dimensional system such as a DNA chain, it was proved that the energy transfer process only carries out within the critical distance based on the F?rster theory and within a threshold value estimated from the modified Stern-Volmer equation. The present results showed that DNA chain is one of the most powerful tools for nanoassemblies and will give a novel concepts of material design.  相似文献   
473.
More than two-fold augmentation in the radical-scavenging activity of artepillin C could be achieved via altering the O-H bond dissociation enthalpy of artepillin C by means of structural modifications.  相似文献   
474.
Nano-hybrid materials of single-walled carbon nanotubes (SWNTs) and polyoxometalates (POMs) with three counter cations were prepared and used as cathode-active materials of molecular cluster batteries (MCBs). The charging/discharging performances and thus battery capacity of the MCBs with hybrid materials were significantly better than those of the microcrystal-POM MCBs.  相似文献   
475.
The electroreduction of aromatic β-dimethylcarbamoyl-β-imino esters, prepared from (S)-aspartic acid, in the presence of chlorotrimethylsilane gave five-membered cyclized products, 1-benzoyl-4-hydroxy-5-aryl-N,N-dimethylpyrrolidine-2-carboxamides and 5-(dimethylcarbamoyl)-2-aryl-1H-pyrrol-3-yl benzoates, depending on the post-treatment after the electroreduction. The electroreduction of aromatic γ-dialkylcarbamoyl-γ-imino and γ-methoxylmethyl-γ-imino esters, prepared from (S)-glutamic acid, and following transformation gave six-membered cyclized products, 1-benzoyl-5-hydroxy-N,N-dialkyl-6-phenylpiperidine-2-carboxamides and 3-hydroxy-6-(methoxymethyl)-2-phenylpiperidin-1-yl)(phenyl)methanones, respectively.  相似文献   
476.
Tin-doped indium oxide (ITO) microcrystals were successfully synthesized in supercritical water (SCW) using hydrazine (N2H4) as a reducing agent. Using a mixture of tin and indium hydroxides prepared at pH = 9.4 as a precursor, ITO microcrystals were synthesized at temperatures 400–450 °C under pressures 25–30 MPa. Synthesizing in SCW effectively shortened the time required to synthesize the ITO microcrystals to below 30 mins. The effect of reducing agents (ethanol, formic acid, and N2H4) and reaction conditions on the formation of ITO particles were investigated, and it was found that N2H4, which is superior to ethanol and formic acid, played a key role in the doping of the In2O3 structure with Sn4+ to form ITO particles with a blue color. Addition of N2H4 possibly depleted the oxygen in the In(Sn)OOH structure, accelerating the formation of cubic In2O3 and introduced Sn4+ into the structure along with the creation of oxygen vacancies. It was also found that the high temperatures and the properties of the SCW, such as ion product, strongly affected the morphology of the ITO particles and the Sn4+ doping. Based on these results, a mechanism has been proposed for the synthesis of ITO particles under SCW conditions. This study demonstrates that due to the unique properties of SCW, the synthesis of doped oxides in SCW is a plausible alternative method.  相似文献   
477.
While a great deal of literature has been published in recent years on the ancillary benefits of greenhouse gas mitigation (e.g., reductions in local air pollution), less attention has been focused on the climate benefits of local air pollution strategies themselves. Local air pollution is, however, a more immediate issue now faced by developing countries. This study assesses the impacts on local air pollutant emission reduction and ancillary CO2 emission reduction of SO2 control policies in China, such as a sulphur tax, SO2 total emissions control (TEC), and improvement of energy efficiency, based on the Asia-Pacific Integrated Model (AIM)/Computable General Equilibrium (CGE) country model. The simulation period is from 1997 to 2020. Major conclusions include the following: an SO2 emission cap will help to control SO2 emissions, but will result in a large GDP loss; the role of a SO2 emission tax at the present level is very limited; and an ancillary carbon reduction benefit can be achieved through the introduction of SO2 control policies in China.  相似文献   
478.
Better the second time around : The title compounds were synthesized by using a one‐pot double methylene transfer catalyzed by a heterobimetallic La/Li complex. Chiral amplification in the second step was the key to obtaining oxetanes in high enantiomeric excess (see scheme).

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479.
A mixing experiment of multicomponents melts was performed using a uniform temperature furnace in the Second International Microgravity Laboratories (IML-2) mission. Growth morphologies and Ga concentration profiles were analyzed for the samples with the compositional ratio of 0.5 In–0.5 Ga–1.0 Sb grown under microgravity and on earth. The sample with free surface grown under microgravity was nearly spherical in shape, except some parts with projections. Ga was dispersed homogeneously in the bulk because the mixing was enhanced by Marangoni convection due to the concentration gradient. On the other hand, the sample grown on earth was a double cylindrical shape with different diameters, and Ga concentration decreased from top to bottom, showing clearly the effect of gravity. Many needle crystals were formed in both space and earth samples due to rapid cooling. The average size of the needle crystals grown in space was larger than that of the earth sample.  相似文献   
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