＜正＞Donor-acceptor conjugated polymers have attracted significant interest recently because their electronic and optoelectronic properties could be easily manipulated through intramolecular charge *** this presentat...
＜正＞Donor-acceptor conjugated polymers have attracted significant interest recently because their electronic and optoelectronic properties could be easily manipulated through intramolecular charge *** this presentation,three different types of thiophene based donor-acceptor copolymer systems are reported as described below:
Trimethoxysilyl-functionalized PPEK（PKGS） films had been designed to serve as wear resistant coatings for silicon surfaces. These surface films were formed by a dip-coating technique applied to self-assembled monola...
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Trimethoxysilyl-functionalized PPEK（PKGS） films had been designed to serve as wear resistant coatings for silicon surfaces. These surface films were formed by a dip-coating technique applied to self-assembled monolayers（SAMs）.The formation and wetting behavior of PKGS films were characterized by means of contact angle *** friction coefficient of the film prepared is very low（about 0.1）,and the anti-wear behavior is good,with a lack of failure after sliding over 1800 s.
In this work, polystyrene (PSt) nanocapsules were successfully prepared by one-stage redox Interfacial-initiated inversed micro-emulsion polymerization of styrene (St), the cumene hydroperoxide (CHPO) and tetraethylen...
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In this work, polystyrene (PSt) nanocapsules were successfully prepared by one-stage redox Interfacial-initiated inversed micro-emulsion polymerization of styrene (St), the cumene hydroperoxide (CHPO) and tetraethylenepentamine (TEPA) as the redox initiation pairs. The water-soluble TEPA acted as the reducing component and the oil-soluble CHPO as the oxidant component of the redox initiation system. The primary radicals were produced mainly at the oil/water interface to initiate the polymerization of styrene (St). Core-shell polymeric PSt nanocapsules were obtained by one-stage polymerization via this method, which was supported by the techniques of transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). The particle size and polydispersity index (PDI) of nanocapsules were determined by dynamic light scattering (DLS). The results demonstrated that interfacial-initiated inversed micro-emulsion polymerization to form core-shell nanocapsules containing liquid cores by one-stage is successful.
Mesoporous TiSBA-15 catalysts have been synthesized using Pluronic P123 as a structuring agent under pH-adjusting direct hydrothermal (pH-aDH) method. The mesoporous TiSBA-15 catalysts characterized by sophisticated i...
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engineering capstone design is a culminating experience that is intended to provide an opportunity for students to apply their previous engineering knowledge to develop solutions to open-ended problems. Capstone desig...
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engineering capstone design is a culminating experience that is intended to provide an opportunity for students to apply their previous engineering knowledge to develop solutions to open-ended problems. Capstone design problems are often analytically complex, and their solutions integrate several disciplinary fundamentals, as well as more general design process knowledge. Often, the expectation is that a thorough or rigorous solution to a capstone level problem would include some type of computational or mathematical analysis appropriate to that discipline. However, engineering students often struggle in recognizing when and how disciplinary knowledge (e.g. mathematical analysis inherent in many engineering fundamentals) applies to their particular design solutions. This paper describes the strategy for and initial results of a study exploring how students use mathematical reasoning when developing design solutions. Specifically, we want to understand where students struggle in the development and implementation of a mathematical model. We conducted our study in a biomedical capstone (senior) design course. We presented students with a scenario based on a design problem in using phototherapy to treat jaundice, and asked specific questions relating to mathematical modeling in the solution to this problem. We developed the scenario and corresponding assignments based on previous work that identified six steps for what mathematical modeling should include. We staged the activities over a four-week period such that students addressed two of these steps at each time interval, or assignment stage. This report analyzes results from the first two activities, which focused on identifying the real-world phenomenon and simplifying or idealizing it. We found that in an open-ended statement of the problem, no students proposed using a mathematical model to assist in designing the device. When we specifically asked for a mathematical model in a second activity, only five students
The function of molten urea as the solvent for wool and other animal proteins were investigated. Molten urea at 150 °C could dissolve wool without addition of water or any other chemicals. Also, it could dissolve...
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The function of molten urea as the solvent for wool and other animal proteins were investigated. Molten urea at 150 °C could dissolve wool without addition of water or any other chemicals. Also, it could dissolve other animal proteins such as hair, feather and silk. When the concentration of wool in molten urea was up to about 10 %, the recovery of water soluble and water insoluble keratins were determined by 13C-CP/MAS NMR spectroscopy. It was found that the water soluble keratin consists of 61 % β-sheet and 39 % α-helix, and the water insoluble keratin almost consists of β-sheet. The result of nitrogen content assay by elementary analyzer revealed that 9.2 % (w/w) urea par water soluble keratin might form chemical bonds with the keratin.
Ethylene homopolymerization and copolymerizations with 1-hexene by three types of MgCl2-supported catalysts were compared. Cat-1 contains no internal electron donor (ID), Cat-2 contains phthalic anhydride (PA) as ID, ...
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Ethylene homopolymerization and copolymerizations with 1-hexene by three types of MgCl2-supported catalysts were compared. Cat-1 contains no internal electron donor (ID), Cat-2 contains phthalic anhydride (PA) as ID, And Cat-3 contains anisole as ID. The influences of two kinds of ID on comonomer effect, The role of hydrogen, polymerization kinetics in ethylene/1-hexene copolymerization were investigated. The addition of ID improves the catalysts activities in ethylene polymerization. In comparison with ethylene homopolymerization, These ethylene/1-hexene copolymerization systems all showed strong comonomer effects. However, Internal donor, Especially anisole, Weakens the extent of comonomer activity enhancement. When the concentration of 1-hexene is 0.6 mol/L, Catalysts activities increase remarkably with adding a small amount of hydrogen. But, The addition of ID reduces the sensitivity of catalyst activity to hydrogen. The introduction of anisole increases the homo-polymerization rate rapidly at the initial stage, But makes it decay earlier. In ethylene/1-hexene copolymerization with hydrogen, The addition of phthalic anhydride as ID can stabilize the polymerization rate, But anisole accelerates the decaying trends. The results are discussed based on a kinetic mechanistic model of the ID effect on ethylene copolymerization.
The effect of material properties of anisotropic conductive films (ACFs) on the reliability of chip on glass (COG) assemblies was investigated. Two types of ACF were used in this study. ACF-A (50wt%) is designed to ha...
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