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排序方式: 共有305条查询结果,搜索用时 218 毫秒
51.
Songshan Zeng Kuangyu Shen Shuliang Li Rui Li Zaili Hou Xin Zhang William R. T. Tait Tomoko Kajiwara Atsushi Takahara Andrew T. Smith Michael D. Jones Dianyun Zhang Luyi Sun 《Advanced functional materials》2021,31(18):2100612
A versatile wrinkle-based micropatterned system with a film-substrate structure is proposed, which contains a hydrophilic film of polyvinyl alcohol or its composite with laponite and a hydrophobic substrate of polydimethylsiloxane or its composite with carbon black. The wrinkled system features high design flexibility and multistimuli responsiveness, which can be activated by various mechanical methods, including vertical press or scratch, gentle stretch-and-release, bend, or analogous magneto-mechanical and electro-mechanical modes. The resultant wrinkles possess 1) instantaneous and reversible strain/moisture/light responsive optical modulation; 2) tunable dynamics for the aforementioned strain/moisture/light response;3) tailorable amplitude/wavelength; 4) unique surface morphologies from the coupling of wrinkles and cracks; 5) excellent reversibility and durability. A variety of applications are demonstrated based on this system, including 1) a moisture erasable highly sensitive pressure responsive device and pattern replicator with a high fidelity; 2) a moisture erasable scratch/magneto-mechanical re-writable tablet; 3) an electro-mechanical controllable smart window with an ultra-sensitive strain responsive transmittance modulation and a low operating voltage; 4) various types of strain responsive, moisture erasable, and laser writable information recording/encryption devices. This work provides new routes for designing innovative wrinkled systems triggered by diverse mechanical fashions and can decode multiple environmental stimuli into optical signals for widespread application. 相似文献
52.
Electron conductivity of hexaalkoxycyclotriphosphazenes N3P3(OR)6 is temperature dependent; the conductivity of the n-propoxy derivatives is dramatically raised at elevated temperature. Tan δ values of hexa-n-propoxy- and hexa-n-butoxy-cyclotriphosphazene increase appreciably at room temperature at high frequency. A chemical shift with 31P-n.m.r. spectra of hexa-n-propoxycyclotriphosphazene appears at the lowest field compared with other hexaalkoxycyclotriphosphazenes. Dipropyl ether or dibutyl ether, respectively, were detected when hexa-n-propoxy- or hexa-n-butoxy-cyclotriphosphazene were heated. It is assumed that a polymerization rather than a rearrangement reaction occurs on heating with the elimation of ethers. 相似文献
53.
Tetrachlorodiphenyl cyclotriphosphazene N3P3Cl4(C6H5)2 (TPC) has been synthesized by Friedel-Crafts reaction. The polycondensation of TPC with aromatic diamine compounds has been carried out in pyridine. The products obtained from the reaction of TPC with aromatic diamine compounds were slightly soluble in polar organic solvents. The molecular weights measured by the method of end group analysis were about 2800 to 10800. The products were amorphous, brown, yellow or white coloured solids. The softening points of all polycondensation products were found to be in the region of 100°C to 120°C. The electrical conductivity of the products obtained from TPC with p-phenylenediamine and p,p′-diaminodiphenyl sulfone was determined to 5 × 1012 (Ωcm)?1 and 1 × 1015 (Ωcm)?1, respectively. 相似文献
54.
Chelating polymers containing copper, nickel and cobalt have been formed from cyclophosphazene thiocarbamate trimer and copper, nickel or cobalt ions. These polymers obtained from the reaction are amorphous and the values of electron conductivity are , and for the Cu, Ni and Co polymers respectively. The Cu polymer is the most thermally stable on heating to 500°C in air. 相似文献
55.
Yasunaga H Ishii Y Komoda T Shinkawa T Kajiwara K Urakawa H 《International journal of cosmetic science》2007,29(4):301-309
The effect of surfactants on an oxidation-hair-dye-formation reaction in a dye bath was studied in order to learn the mechanism of the effect of surfactants on the dyeability of hair by the oxidation dye. The dye-formation behaviours for the p-aminophenol and 5-amino-o-cresol system with the surfactants, of which the hydrophilic parts have different charges, were compared changing the concentration of surfactants. It was found that the same dyes are produced, regardless of the charge of surfactants added, and the rate of dye produced in the dyebath is increased in the presence of surfactants. The order of the production rate is, with an anionic surfactant > with non-ionic surfactant > with cationic surfactant > without surfactant. The relation between the dyeability of hair and the rate of dye produced in the dyebath in the presence of surfactants is not found. The major factor governing the dyeability of hair is different from the mechanism of the increased dye in the solution. It was also found that the dye-formation rate is increased by immersing hair into the reaction solution, and hair works as an accelerator for the dye-formation reaction. 相似文献
56.
Hiroyuki Nishikawa Eiki Watanabe Daisuke Ito Yoshimichi Ohki 《Electrical Engineering in Japan》1997,121(3):9-19
The formation mechanisms of paramagnetic defect centers in amorphous SiO2 induced by excimer lasers, 60Co γ rays, and mechanical fracturing were investigated. Correlation between the paramagnetic defect centers and their precursors introduced during manufacture is discussed for the cases of excimer lasers and γ rays. For the case of mechanical fracturing, formation of strained Si·O·Si bonds as well as paramagnetic defects is examined. The mechanism of laser- or γ-ray-induced paramagnetic defect centers is compared with that of fracture-induced centers. © 1998 Scripta Technica, Inc. Electr Erg Jpn, 121(3): 9–19, 1997 相似文献
57.
软件需求定量分析及其映射的模糊层次分析法 总被引:10,自引:0,他引:10
在用数量化理论3类(quantification theory of type 3,简称QT3)定量地分析软件需求的基础上,以质量功能展开(quality function deployment,简称QFD)中的质量屋(house of quality,简称HOQ)系列矩阵为纲领,基于由模糊技术改进后的模糊层次分析法(fuzzy analytic hierarchy process,简称FAHP),提出了一种软件需求定量分析及其向设计实现过程模糊映射的方法.将该方法具体应用于CD-R/RW光盘刻录机软件的开发过程,其有效性得到了验证. 相似文献
58.
59.
The effect of osmotic dehydrofreezing on the role of the cell membrane in carrot texture softening after freeze-thawing 总被引:1,自引:0,他引:1
Hiroko AndoKazuhito Kajiwara Seiichi OshitaToru Suzuki 《Journal of food engineering》2012,108(3):473-479
To understand the protective mechanism of the osmotic dehydrofreezing technique on carrot texture after freeze-thawing, two mechanical texture parameters, fracture stress related to the cell wall and initial modulus related to the cell membrane, as well as cell membrane water permeability using PFG-NMR were evaluated. In particular, to understand the role of the cell membrane in texture alteration, tissue in which the cell membrane was exposed to chloroform vapor was used. Although dehydrofreezing protected texture from freezing damage, the effect was only observed with respect to fracture stress, with exhibited values close to those for raw tissue. However, there was no protective effect on initial modulus and water permeability, in which values did not differ from those of cell membrane-free tissue. More specifically, osmotic dehydrofreezing had no effect on the cell membrane induced by freeze-thawing. 相似文献
60.
Effects of the type and amount of fatty acid (0-2.0 mmol/g-starch of lauric, myristic, palmitic, stearic, oleic, and linoleic acids) on the complex formation, thermal properties, and in-vitro digestibility of gelatinized potato starch-fatty acid mixtures were investigated. Complex index (CI) evaluated by the reduction in the iodine binding capacity of starch increased with an increase in the amount of fatty acids, and reached a plateau depending on the type of fatty acid. The maximum CI value was higher in the order of lauric (49.9%), linoleic (47.6%), myristic (42.4%), oleic (36.7%), stearic (35.3%), and palmitic acid (30.9%). From the calorimetric study, it was demonstrated that melting temperature of the complexes was higher in the order of stearic (96.7 °C) > lauric, myristic, palmitic, and oleic (89.6-92.1 °C) > linoleic acid (78.3 °C). Melting enthalpy for complexes was roughly related to the CI value (R2 = 0.667). From the in-vitro digestibility measurement, it was found that a certain amount of fatty acid reduced the starch content hydrolyzed at a given condition. Among them, 0.50 mmol/g-starch lauric and oleic acid samples showed the largest reduction in the hydrolyzed starch content. This result was related to the extent of complex formation characterized by CI value and its helical order characterized by melting temperature. In addition, there was a possibility of the complex formation between amylose and unsaturated fatty acid during the hydrolysis of gelatinized starch. 相似文献