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41.
Ethanolamine plasmalogen (PlsEtn), which is present at high levels in brains, is believed to be involved in neuronal protection. The present study was performed to search for PlsEtn resources in foodstuffs. The foodstuffs examined showed a wide range of PlsEtn contents from 5 to 549 μmol/100 g wet wt. The marine invertebrates, blue mussel, and ascidian had high PlsEtn contents (over 200 μmol/100 g wet wt). Profiling of the molecular species showed that the predominant fatty acids of PlsEtn species were 20:5 (EPA) and 22:6 (DHA) at the sn‐2 position of the glycerol moiety in marine foodstuffs, whereas major PlsEtn species in land foodstuffs were 20:4. Following quantitative analysis by multiple reaction monitoring, the ascidian viscera were shown to contain the highest levels of 18:0/20:5‐PlsEtn and 18:0/22:6‐PlsEtn (86 and 68 μmol/100 g wet wt, respectively). In order to evaluate a neuronal antiapoptotic effect of these PlsEtn species, human neuroblastoma SH‐SY5Y cells were treated with ethanolamine glycerophospholipid (EtnGpl), purified from the ascidian viscera, under serum starvation conditions. Extrinsic EtnGpl from ascidian viscera showed stronger suppression of cell death induced by serum starvation than with bovine brain EtnGpl. The EtnGpl from ascidian viscera strongly suppressed the activation of caspase 3. These results suggest that PlsEtn, especially that containing EPA and DHA, from marine foodstuffs is potentially useful for a therapeutic dietary supplement preventing neurodegenerative diseases, such as Alzheimer's disease (AD).  相似文献   
42.
Sputter deposition is currently being widely used in the microelectronics industry for the production of silicon integrated circuits. Recently interest has been focused on sputter deposition as a new materials processing technique. The highly energetic sputtered atoms enhance crystal growth and/or sintering during film growth. This results in lowering of the growth temperature of high temperature materials including cubic diamonds. Single crystals of complex ceramics materials could be prepared by sputter deposition through epitaxial growth process. Atomically controlled deposition using multi-target sputter enables to make man-made superlattice including high-T C superconductors of layered perovskite. At present sputter deposition is one of key materials technologies for the coming century.  相似文献   
43.
Nickel monoaluminide, NiAl, is exothermically synthesized from elemental liquids of aluminum and nickel and is simultaneously joined to iron-based alloys, such as carbon steels and stainless steels, by the reactive casting method, which is based on the pouring of the elemental liquids onto the base material. The exothermic reaction between the aluminum and nickel liquids produces extremely superheated NiAl liquid. Heat of the NiAl liquid is transferred to the base material, and the contact surface is melted to a depth depending on both the preheating temperature of the base material and the thickness of the NiAl produced. After solification on the base material, NiAl is strongly joined to the base material, showing a joint strength exceeding the inherent strength of NiAl. The high joint strength is attributed to a very fine, rodlike eutectic structure at the joint interface that consists of a mixture of β-NiAl and γ-iron with an interrod spacing of approximately 100 nm.  相似文献   
44.
In general, manipulators used for industry and in academic laboratories have actuators to drive each joint. On the other hand, underactuated manipulators handled by our research have some passive or free joints without actuators and brakes. We recently developed a switching method of fuzzy energy regions to control such manipulators. In such a method, it is necessary to design parameters related to energy regions and the gains of some partly stable controllers based on the computed torque method. Here, the switching method is applied for a three-link underactuated manipulator. We optimize such design parameters related to fuzzy energy regions by a genetic algorithm. The effectiveness of the present method is illustrated with some simulations. This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007  相似文献   
45.
46.
Humidity Sensor Characteristics of Woodceramics   总被引:9,自引:0,他引:9  
The humidity sensor characteristics of Woodceramics were investigated. The Woodceramics used in this experiment were prepared at 650–900°C. The size of specimens selected was 1 × 1 × 10 mm . One was used as-cut and the other was polished. Above 700°C, the resistance of the specimen was below 50 and the decrease of resistance with increasing relative humidity was small. The specimen prepared at 650°C had a resistance of about 1 k. The resistance of as-cut specimens decreased with increase in relative humidity, but that of the polished specimen did not change significantly. The difference between as-cut and polished samples was explained by the differences in surface micro-structure.  相似文献   
47.
Electromagnetic Shielding Properties of Woodceramics Made from Wastepaper   总被引:18,自引:0,他引:18  
Woodceramics are new porous carbon materials, which are made by impregnating woody materials with phenol resin and then thermoformed in a vacuum furnace and these have been shown to have electromagnetic shielding properties. In the recycling of wastepaper, ways of using the wastepaper other than for paper pulp are needed to be developed. In this study, we made Woodceramics from handbill advertisement paper and telephone directory paper, and measured their electromagnetic shielding properties in order to find new uses for wastepaper. The results showed that the Woodceramics made from wastepaper had an electric shielding effectiveness of 30 dB for 100 MHz and 40 to 43 dB for 300 MHz or higher, and had a magnetic shielding effectiveness of 30 dB for 100 MHz and 37 dB for about 400 MHz. An electric equivalent circuit of the pore model in the Woodceramics is introduced. In addition, it is proposed that the excellent electromagnetic shielding effectiveness of the Woodceramics is caused by dielectric loss.  相似文献   
48.
The reaction of N-(2,4-dinitrophenyl)pyridinium anion ( salt(A) ; A = Cl, FeCl4, and (CN)2N) with linear polyethyleneimine (LPEI; Mn = 20 380) and branched polyethyleneimines (BPEI1; Mn = 600, BPEI2; Mn = 10 000) at various molar feed ratios without using a catalyst resulted in pyridinium ring opening to yield ionic LPEI and BPEIs that were crosslinked by conjugated penta-2,4-dienylideneammonium (PDA) units, LPEI-PDA , BPEI1-PDA , and BPEI2-PDA , respectively. A model compound was synthesized by the reaction of salt(Cl) with diethylamine. The solubilities of BPEI1-PDA and BPEI2-PDA depended on the feed ratios between salt(Cl) and BPEI1 or BPEI2. Dipping LPEI-PDA into water and methanol yielded hydro- and organogels, respectively. UV–vis and reflection measurements revealed an expanded π-conjugation length between the polymer chains due to the through-space orbital interaction of the electrons on the two nitrogen atoms at the crosslinked positions in LPEI-PDA , BPEI1-PDA , and BPEI2-PDA . Cyclic voltammetry analysis suggested that the polymers underwent electrochemical oxidation. Measurement using a superconducting quantum interference device (SQUID) indicated that LPEI-PDA having FeCl4 anions was paramagnetic. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48712.  相似文献   
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50.
Effects of seeding of fat crystals on the crystallization kinetics of cocoa butter and dark chocolate were examined with a rotational viscometer. The seed crystals employed were cocoa butter, 1,3-distearoyl-2-oleoylglycerol (SOS), 1,3-dibehenoyl-2-oleoylglycerol (BOB) and 1,2,3-tristearoylglycerol (SSS). The seed powders were prepared by pulverization below —50°C, the dimensions being in a range from 20–70 μm. Particular attention was paid to the influence of polymorphism of the seed crystal. We found that all of the above seed materials accelerated the crystallization, the degree of acceleration being in a following order; SOS (β 1) > cocoa butter (Form V) > SOS (a mixture ofβ’ andβ 2) > BOB (β 2) > BOB (pseudo-β’) > SSS (β). Precise measurements of the crystallization kinetics showed that the most influential factors in the seeding effects are the physical properties of the seed materials—above all, thermodynamic stability, and similarity in the crystal structure to cocoa butter are the most determinative.  相似文献   
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