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101.
Solution phase synthetic method for amyloid-cleaving catalysts was developed, which bears triazine core, scaffold with bulky and that have various solubility properties; Co(III) complex of cyclen (1,4,7,10-tetraazacyclododecane) for catalytic group, and two imaging agents for binding group. This synthetic method was identified by H-NMR, C-NMR for intermediates and MS for the last products. The yields by this method surpassed solid phase synthesis and took much lower labor, expense, and time. The products which were synthesized by solution phase synthetic method showed good catalytic activities.  相似文献   
102.
103.
The purpose of this study was to analyze the exhaust emissions of DME fuel through experimental and numerical analyses of in-cylinder spray behavior. To investigate this behavior, spray characteristics such as the spray tip penetration, spray cone angle, and spray targeting point were studied in a re-entrant cylinder shape under real combustion chamber conditions. The combustion performance and exhaust emissions of the DME-fueled diesel engine were calculated using KIVA-3V. The numerical results were validated with experimental results from a DME direct injection compression ignition engine with a single cylinder.The combustion pressure and IMEP have their peak values at an injection timing of around BTDC 30°, and the peak combustion temperature, exhaust emissions (soot, NOx), and ISFC had a lower value. The HC and CO emissions from DME fuel showed lower values and distributions in the range from BTDC 25° to BTDC 10° at which a major part of the injected DME spray was distributed into the piston bowl area. When the injection timing advanced to before BTDC 30°, the HC and CO emissions showed a rapid increase. When the equivalence ratio increased, the combustion pressure and peak combustion temperature decreased, and the peak IMEP was retarded from BTDC 25° to BTDC 20°. In addition, NOx emissions were largely decreased by the low combustion temperature, but the soot emissions increased slightly.  相似文献   
104.
105.
Lipid ingredients that demonstrate high stability and positive health profiles without the use of trans‐fats are needed in the food supply. Rice bran oil can be fractionated at low temperatures to create a series of spreads that show promise as functional ingredients. A rice bran oil‐derived spread can extend the fry life of soybean oil and can also be incorporated into baked goods such as bread and granola as a trans‐fat free alternative to butter or shortening.  相似文献   
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107.
An anion‐exchange membrane was prepared by the amination of chlorinated polypropylene and polyethyleneimine at a low temperature and was investigated with respect to not only its physical properties but also its electrochemical properties. The degrees of amination were 50.16, 53.76, 57.11, and 65.29% at 30, 40, 50, and 55°C, respectively. The base polymer membrane had no water uptake, whereas that of the aminated polymer membrane was 0.254, 0.296, 0.298, and 0.319 g of H2O/g of dry membrane, respectively, with increasing amination. The prepared membranes possessed an ion‐exchange capacity in the range of 1.257–2.000 mequiv/g of dry membrane and a fixed ion concentration in the range of 4.492–6.261 mequiv/g of H2O. The ionic conductivity of the aminated polymer membrane was highest when the water uptake was highest. Those of the prepared membrane were in the range of 0.89 × 10?2 to 1.36 × 10?2 S/cm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
108.
Newly proposed polymer electrolyte membranes (PEMs) composed of an electrospun poly(vinylidene fluoride) (PVDF) fibrous mat embedded in a poly(4‐vinylpyridine) (P4VP) matrix were successfully fabricated in order to improve the mechanical and dimensional stabilities and ionic conductivity of membranes in lithium rechargeable batteries. Fourier transform infrared spectroscopic analysis showed that as a result of the use of a high voltage during electrospinning the crystalline structure of PVDF changed partially from α‐phase to β‐phase. Energy‐dispersive X‐ray spectroscopy confirmed the existence of crosslinked P4VP in the PVDF fibrous mat. The electrolyte uptakes of PVDF and PVDF/P4VP composite mats were higher than that of PVDF cast film. The tensile properties of PVDF/P4VP composite mat were considerably improved compared to those of the pristine PVDF fibrous mat under both dry and wet (soaked with electrolyte) conditions. In addition, the mechanical and dimensional stabilities of the PVDF/P4VP composite PEM were further enhanced due to crosslinking between the P4VP chains. Furthermore, the PVDF/P4VP composite PEM exhibited an ionic conductivity that was an order of magnitude higher than that of traditional PVDF film. © 2012 Society of Chemical Industry  相似文献   
109.
Sn whisker growth behavior, over periods of time up to 10,080 h at room temperature, was examined for Sn and Sn-Cu, Sn-Ag, Sn-Bi, and Sn-Pb coatings electroplated on copper in 2 μm and 5 μm thicknesses to understand the effects of the alloying elements on whisker formation. Sn-Ag and Sn-Bi coatings were found to significantly suppress Sn whisker formation compared with the pure Sn coatings, whereas whisker growth was enhanced by Sn-Cu coatings. In addition, annealed Sn and Sn-Pb coatings were found to suppress Sn whisker formation, as is well known. Compared with the 2-μm-thick coatings, the 5-μm-thick coatings had high whisker resistance, except for the Sn-Cu coating. Whisker growth was correlated with coating crystal texture and its stability during storage, crystal grain microstructure, and the formation of intermetallic compounds at Sn grain boundaries and substrate–coating interfaces.  相似文献   
110.
For several years recently, the price of oil has fluctuated due to the weak US dollar and financial risks. In particular, the WTI crude oil price reached $147 per barrel in July of 2008, which is the highest price thus far. An awareness of an impending crisis and concern over climate change are driving an increase in R&D for alternative energy sources instead of fossil‐based energy. However, the researches based on traditional method show negative options about the economic value of new and renewable energy. This paper evaluates the value of new and renewable energy through a real option method which considers the uncertainty associated with fossil energy and the uncertainty of the success of R&D. The evaluating model assumes that the fossil energy price follows a geometric mean reverting process and that the probability of success with R&D on renewal forms of energy follows a binomial probability model. The model considers four options: the option to continue R&D, the option to delay R&D, the option to deploy R&D, and the option to abandon R&D. Finally, the value of Korean R&D on renewal forms of energy is analyzed by the model. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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