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41.
42.
Poly(ethylene glycol)‐crosslinked multimeric C60 was developed for use in photothermal/photodynamic therapy of malignant cells. We showed that: (i) the tumor surface temperature on KB tumor‐bearing nude mice treated with multimeric C60 reached about 44 °C; (ii) this hyperthermic condition and tremendous singlet oxygen generation from multimeric C60 resulted in significant tumor volume regression in KB tumor‐bearing nude mice; and (iii) multimeric C60 also efficiently inhibited arthritic progress in the arthritis‐induced DBA/1 J mice model. This multimeric C60 may be useful for photothermal/photodynamic cell ablation in various malignant cells. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
43.
Dr. Wonhee Lee Young Eun Kim Dr. Min Hye Youn Dr. Soon Kwan Jeong Dr. Ki Tae Park 《Angewandte Chemie (International ed. in English)》2018,57(23):6883-6887
Electrochemical reduction of carbon dioxide (CO2) into value‐added chemicals is a promising strategy to reduce CO2 emission and mitigate climate change. One of the most serious problems in electrocatalytic CO2 reduction (CO2R) is the low solubility of CO2 in an aqueous electrolyte, which significantly limits the cathodic reaction rate. This paper proposes a facile method of catholyte‐free electrocatalytic CO2 reduction to avoid the solubility limitation using commercial tin nanoparticles as a cathode catalyst. Interestingly, as the reaction temperature rises from 303 K to 363 K, the partial current density (PCD) of formate improves more than two times with 52.9 mA cm?2, despite the decrease in CO2 solubility. Furthermore, a significantly high formate concentration of 41.5 g L?1 is obtained as a one‐path product at 343 K with high PCD (51.7 mA cm?2) and high Faradaic efficiency (93.3 %) via continuous operation in a full flow cell at a low cell voltage of 2.2 V. 相似文献
44.
[reaction: see text] Asymmetric diol boronic esters with potassium bifluoride form the corresponding alkyltrifluoroborate and free diol under mild conditions. Defluoridation with tetrachlorosilane produces an alkyldifluoroborane intermediate. This conversion of relatively unreactive boronic esters to derivatives that are strong Lewis acids opens new synthetic opportunities, as illustrated by the preparation of (R)-2-phenylpyrrolidine in 98% ee from a pinanediol or 1,2-dicyclohexyl-1,2-ethanediol boronic ester via potassium (2-phenyl-4-azidobutyl)trifluoroborate. 相似文献
45.
Pressure reducing valves are widely used to maintain the pressure of gas reservoirs to specific values. In a normal valve,
supply pressure is decompressed with an orifice structure. When compressed air passes through the orifice structure, considerable
noise occurs at the downstream side. In this paper, we have developed a radial slit structure that can reduce pressure without
noise. The noise is reduced by changing the orifice structure into the radial slit structure. The radial slit structure valve
reduces pressure without noise by suppressing the generation of turbulence and shock wave at the downstream. The analysis
of the flow in radial slit structure was achieved by CFD2000 software. The flow rate and pressure distribution were simulated
and compared with the experimental result. To confirm the generation of shock wave, the flow of orifice and radial slit structure
at the downstream was visualized by Schlieren photography method. A shock wave was generated in the orifice structure, but
no shock wave was generated in the radial slit structure. Noise reduction efficiency was investigated by the experiment. The
experiment apparatus was set up to JIS standards. The experimental results indicated that the noise level decreased by approximately
40 dB in the slit structure. It is confirmed that the radial slit structure has effectiveness for low noise in the pressure
reducing flow. And, it is expected that it can be applied to various kinds of industrial fields. 相似文献
46.
Analytical models for virus transport in saturated, homogeneous porous media are developed. The models account for three-dimensional dispersion in a uniform flow field, and first-order inactivation of suspended and deposited viruses with different inactivation rate coefficients. Virus deposition onto solid particles is described by two different processes: nonequilibrium adsorption which is applicable to viruses behaving as solutes; and colloid filtration which is applicable to viruses behaving as colloids. The governing virus transport equations are solved analytically by employing Laplace/Fourier transform techniques. Instantaneous and continuous/periodic virus loadings from a point source are examined. 相似文献
47.
Isolation and structure determination of a novel furanic ester from the aerial part of Prasium majus
The aerial part of Prasium majus provided a new furanic ester, 2-2-[(5-formyl-6[(5-formylfuran-2-yl)methoxy] succinic acid dimethyl ester, (+/-)-hiziprafuran. Its structure was principally established by one- and two-dimensional NMR spectroscopy. 相似文献
48.
Cho S Youn SJ Kim Y DiVenere A Wong GK Freeman AJ Ketterson JB 《Physical review letters》2001,87(12):126403
We have observed an epilayer-thickness-dependent polarity inversion for the growth of CdTe on Sb(Bi)/CdTe(111)B. For films with Sb(Bi) thicknesses of less than 40 A (15 A), the CdTe layer shows a B (Te-terminated) face, but it switches to an A (Cd-terminated) face for thicker layers. On the other hand, a CdTe layer grown on Bi(Sb)/CdTe(111)A always shows the A face regardless of Sb or Bi layer thicknesses. In order to address the observations we have performed ab initio calculations, which suggest that the polarity of a polar material on a nonpolar one results from the binding energy difference between the two possible surface configurations. 相似文献
49.
50.
Ing Youn Chen Chih-Yung Tseng Yur-Tsai Lin Chi-Chuan Wang 《International Journal of Multiphase Flow》2009
This study investigates the pressure change and flow pattern subject to the influence of sudden contractions. The air and water mixture flows from small rectangular channels (2 × 4, 2 × 6, 4 × 4 and 4 × 6 mm, respectively) into a 2 mm diameter tube. The total mass flux (G) ranges from 100 to 700 kg/m2 s with gas quality (x) being varied from 0.001 to 0.8. In general the contraction pressure change increases with the rise of mass flux, and gas quality but an unique deflection of contraction pressure change pertaining to liquid vena contracta at a very low gas quality is encountered at a very low gas quality in the 4 ± 6 mm test section. For a low gas quality, elongated bubble prevails after the contraction, yet the size of elongated bubbles is reduced when the aspect ratio is increased. Comparisons amid the pressure change data of this study and available literature data with the predictions of existing model/correlations indicate that none of them can accurately predict the data. It is found that the influence of surface tension and outlet tube size, or equivalently the Bond number plays a major role for the departure of various models/correlations. Among the models/correlations being examined, the homogeneous model shows a little better than the others. Hence by taking account the influences of gas quality, Bond number, Weber number and area contraction ratio into the homogeneous model, a modified homogeneous correlation is proposed that considerably improves the predictive ability over existing correlations with a mean deviation of 30% to all the data. 相似文献