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排序方式: 共有2258条查询结果,搜索用时 15 毫秒
971.
Mahsa Gifani Devon J. Eddins Hisanori Kosuge Yapei Zhang Sesha L. A. Paluri Timothy Larson Nicholas Leeper Leonore A. Herzenberg Sanjiv Sam Gambhir Michael V. McConnell Eliver E. B. Ghosn Bryan Ronain Smith 《Advanced functional materials》2021,31(37):2101005
Disruption of vulnerable atherosclerotic plaques often leads to myocardial infarction and stroke, the leading causes of morbidity and mortality in the United States. A diagnostic method that detects early-stage high-risk atherosclerotic plaques could prevent these sequelae. The abundant immune cells in the arterial wall, especially inflammatory Ly-6Chi monocytes and foamy macrophages, are indicative of plaque inflammation, and may be associated with plaque vulnerability. Hence, a new method is sought to develop that specifically targets these immune cells to offer clinically relevant diagnostic information about cardiovascular disease. Ultraselective nanoparticle targeting of Ly-6Chi monocytes and foamy macrophages and clinically-viable photoacoustic imaging (PAI) are combined in order to precisely and specifically image inflamed plaques ex vivo in a mouse model that mimics human vulnerable plaques histopathologically. Within the plaques, high-dimensional single-cell flow cytometry (13-parameter) shows that the nanoparticles are almost-exclusively taken up by the Ly-6Chi monocytes and foamy macrophages that heavily infiltrate plaques. PAI identifies inflamed atherosclerotic plaques that display ≈6-fold greater signal compared to controls (P < 0.001) 6 h after intravenous injection of ultraselective carbon nanotubes, with in vivo corroboration via optical imaging. This highly-selective strategy may provide a targeted, noninvasive imaging strategy to accurately identify and diagnose inflamed atherosclerotic lesions. 相似文献
972.
Kento Yokoo Akinobu Wakizaka Masahiro Kishida Tsuyoshi Yamamoto 《Advanced Powder Technology》2021,32(1):151-165
A fluidized bed filter can perform highly efficient PM collection and low-temperature continuous regeneration. However, to further reduce continuous regeneration temperature, a rough surface bed particle was selected herein. It is expected that the rough surface increases and stabilizes doped catalyst on bed particle even in fluidized bed. This bed particle can stably support 9.48 g-catalyst/kg-bed particle of doped catalyst versus 1.58 g-catalyst/kg-bed particle in previous research. This increase in catalyst amount increases the probability of good PM-catalyst contact, and collection efficiency can easily maintain its initial value due to catalytic PM combustion. PM combustion also depends on fluidization. Thus, combustion kinetics in a fluidized bed was investigated via a newly developed thermogravimetric analyzer that considered PM-gas relative velocity, and a constructed kinetic model was applied to numerical simulation. PM combustion obeyed an Arrhenius relationship, and the effect of PM-gas relative velocity was included in the kinetic model as a mass transfer term. A continuous regeneration experiment was conducted under optimal conditions, and the continuous regeneration temperature is 330 °C. As water vapor occurs in combustor exhaust, we added 10 vol% water vapor and found that the continuous regeneration is further reduced to 300 °C. 相似文献
973.
Noppakhate Jiraborvornpongsa Toshihiro Isobe Sachiko Matsushita Akira Yamaguchi Masahiro Miyauchi Masato Wakamura Akira Nakajima 《Advanced Powder Technology》2019,30(8):1617-1624
Titanium-doped hydroxyapatite (Ti-HAp, (Ca10-2x, Tix, □x) (PO4)6(OH)2, □: defect in Ca site) and hydroxyapatite (HAp, Ca10(PO4)6(OH)2) powders were modified with an ethanol solution of molybdenyl acetylacetonate (MoO2(C5H8O2)2) using chemisorption calcination cycle (CCC) technique, which provides metal oxide clusters. Their photocatalytic activity under UV illumination was evaluated by the decomposition of gaseous 2-propanol. The photocatalytic activity of the Mo-modified Ti-HAp samples increased concomitantly with increasing Mo concentration up to 0.72% against P. The highest photocatalytic activity of Mo-modified Ti-HAp was about 13 times higher than that of Ti-HAp. The signal appearance of Mo(V) in electron spin resonance spectra and the decrease of photoluminescence intensity suggest electron transfer from the Ti-hybridized band to the MoOx cluster, which suppresses recombination of the photoinduced electron and hole pairs. The photocatalytic activity of Mo-modified HAp samples was attributed to HOMO–LUMO excitation of MoOx cluster. 相似文献
974.
Highly efficient white OLEDs with single solution‐processed emitting layer fabricated by one‐step coating using self‐layered technique
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Hirotaka Sakuma Motoko Harada Hironori Wakana Shunichiro Nobuki Masahiro Kawasaki Sukekazu Aratani 《Journal of the Society for Information Display》2015,23(12):587-592
We propose a self‐layered technique to form an emitting layer with a pseudo‐multilayered structure by one‐step coating and demonstrate the feasibility of its concept. We also fabricated a highly efficient white organic light‐emitting diode with the proposed technique. A maximum power efficiency of 70 lm/W was obtained by improving the effective radiation efficiency, carrier balance efficiency, and light‐extraction efficiency. 相似文献
975.
The synthesis of MTBE was studied in the gas phase at elevated temperatures (up to 175°C) and low pressures (150 kPa) where the MTBE formation rate is limited by thermodynamic equilibrium, using various solid acid catalysts (Amberlyst-15 resin, silica-alumina, HY and H-ZSM-5 zeolites). All the zeolites studied were found to exhibit better selectivities to MTBE than the commercially used Amberlyst-15 resin catalyst. The formation of byproducts increased with increasing temperature and appeared to have a strong enhancing effect on catalyst deactivation. H-ZSM-5 seems to be more suitable for high temperature formation of MTBE because of its excellent selectivity towards MTBE and low deactivation behavior. 相似文献
976.
Adiabatic cocurrent flow of air and water through a narrow passage between two flat plates 240 mm long and 99mm wide with gap-widths of 0.778 mm and 1.465 mm was investigated for six different orientations: Vertically upward and downward, 45° inclined upward and downward, and horizontal flows between horizontal plates and between vertical plates. Except for horizontal flow between vertical plates, the effects of gap width and flow channel orientation on flow pattern, void fraction and friction pressure drop were found to be small in narrow channels. The void fraction and two-phase friction multiplier data could also be reasonably correlated in terms of the Martinelli parameter. For horizontal flow between vertical plates, both the void fraction and friction multiplier data showed strong mass velocity effects. Several friction pressure drop correlations were tested for applicability to the narrow channels including a separated flow model proposed in this work. 相似文献
977.
Shinjoh Hirohumi Tanabe Toshitaka Sobukawa Hideo Sugiura Masahiro 《Topics in Catalysis》2001,16(1-4):95-99
The catalytic activity of Pt catalyst loaded on -alumina was improved by Ba addition in simulated automotive exhaust gases. On the other hand, the result of Rh catalyst was the opposite. From the results of the partial reaction orders in C3H6–O2 reaction and TPR, it was concluded that the Ba addition to Pt catalyst suppressed the hydrocarbon chemisorption on the Pt catalyst and therefore allowed the catalytic reaction to proceed smoothly. On the other hand, Ba addition to Rh catalyst caused such a strong oxygen adsorption on Rh that rejected the hydrocarbon adsorption and suppressed the reaction. 相似文献
978.
Naoko Yamaguchi Daisuke Ando Kiyoharu Tadanaga Masahiro Tatsumisago 《Journal of the American Ceramic Society》2007,90(6):1940-1942
Amorphous Al2 O3 –MgO thin films with an Mg/Al ratio of unity were prepared on glass substrates by the sol–gel method with a heat treatment at 300°C for 30 min. By immersing the films in water containing sodium hydroxide (pH 10–13) at 100°C, nano-crystals of Mg–Al-layered double hydroxide (LDH) with a hexagonal structure, which is called hydrotalcite and the most basic composition of LDH, were precipitated on the amorphous Al2 O3 –MgO films. The maximum amount of Mg–Al nanocrystals was obtained when the film was immersed in basic solution of pH 12. 相似文献
979.
Yoshiyuki Yokogawa Nobuo Ishizawa Shigeyuki Smiya Masahiro Yoshimura 《Journal of the American Ceramic Society》1991,74(9):2073-2076
The Phase relations of the system Gd2 O3 -Ta2 O5 in the composition range 50 to100 mol% Gd2O3 was studied by solidstate reactions at 1350°, 1500°, or 1700°C and by thermal analyses up to the melting temperatures. Weberite-type orthorhombic phase (W2 phase, space group C2221) with the composition of Gd3 TaO7 seems to melt incongruently; at about 2040°C, although this Gd3 TaO7 Phase was previously reported to melt congruently. A new fluorite-type cubic phase (F phase, space group Fm3m ) was found for the first time above 1500°C in the system. It melts congruently with the composition of about 80mol% Gd2O3at 2318° 3°C. A phase diagram was proposed for the system Gd2 O3–Ta2O5 in the Gd2 O3 –rich portion 相似文献
980.
Modification of the carbonization properties of coal-tar pitch by supercritical fluid extraction 总被引:1,自引:0,他引:1
The carbonization properties of coal-tar pitch were modified by supercritical fluid (SCF) extraction. Pitches extracted with supercritical toluene (SCFE pitch) contained none of the quinoline insoluble (QI) matter responsible for anisotropic structures with small unit sizes. The size of anisotropic structures from SCFE pitches was closely related to the β-resin (toluene insoluble and quinoline soluble fraction) content. Anisotropic structures from blended pitches prepared to have the same β-resin content as SCFE pitches (by blending toluene soluble (TS) and β-resin fractions obtained through a conventional liquid solvent extraction) were smaller. Extraction of the β-resin fraction with supercritical toluene could be interpreted by the co-solvent effects of the TS fraction dissolved in the extract phase. The high concentration of TS fraction in the extract phase enhanced the solubility of the β-resin fraction into this phase. In the raffinate phase, the heavier β-resin components, which are unsuitable for the development of mesophase structures, coagulated and formed unextractable QI matter through reduction in the concentration of the TS fraction. Since the TS concentration in both the phases depends on pressure and the ratio of the amounts of supercritical toluene and pitch, the control of the β-resin content in the SCFE pitches is possible through the adjustment of these two parameters. 相似文献