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91.
Yung‐Hsin Huang Ting‐Jang Lu Cheng‐Chun Chou 《International Journal of Food Science & Technology》2011,46(2):257-262
Sufu, a fermented soybean curd, was prepared by ripening the salted tofu cubes in the Aspergillus oryzae‐fermented rice–soybean koji mash at 25, 35 or 45 °C for a period of 16 days. It showed that the 16‐day ripened sufu contains less total isoflavone content (629.29–739.68 μg g?1 dried matter) than the salted tofu before ripening (942.59 μg g?1 dried matter). Regardless of ripening temperature, ripening causes a major reduction in the content of β‐glucoside and malonylglucoside isoflavones along with a significant increase of aglycone isoflavone content. These changes were enhanced as the ripening period extended. Among the various treatments examined, sufu ripened at 45 °C showed the greatest increase in aglycone content coupled with the greatest decrease in malonylglucosides. The distribution of malonylglucosides decreased from an initial 40.32% in the tofu cube to 9.78% after 16 days of ripening at 45 °C. Meanwhile, the distribution of aglycone increased from 13.17% to 39.88%. 相似文献
92.
Abstract Diamond crystals have been successfully synthesized on (100) Si wafer using microwave plasma CVD. The growth was conditioned in a flowing system in which the parameters, such as CH4/H2 ratio, pressure, temperature and microwave power were varied. Cubo‐octahedra or tetrakaidecahedra are the equilibrium shape of diamond single crystals obtained under all conditions and are therefore the basic unit for the formation of polycrystalline diamond films, mostly through repetitive twinning and secondary growth of diamond crystals on {100} habit planes of cubo‐octahedra. Both X‐ray diffraction and Raman spectroscopy were used to facilitate the analysis of the diamond crystallinity and purity. These qualities are similar to those of natural diamonds. 相似文献
93.
K.C. Yung X. Gu C.P. Lee H.S. Choy 《Journal of Materials Processing Technology》2010,210(15):2268-2272
A camera flash-lamp, which makes use of the enhanced photothermal effect in silver nanoparticles, was used for sintering of ink-jet printed silver tracks on Polyimide (PI), Polyethylene Terephthalate (PET) and photographic paper at room temperature. After the camera flashing the nonconductive tracks was changed and became conductive. The resistivity of all tracks on different substrates was decreased after the first flashing and the second flashing, while it exhibited a slight increase after the third and forth flashing. Irrespective of the number of flashings, the silver track printed on the PET substrate had the lowest resistivity and it can reach 6.2 μΩ cm after the second flashing, while the track that was printed on the photographic paper had the highest measured resistivity due to defects in the substrate. The thermal conductivity of the substrate had an important effect on the microstructure of the silver tracks after the flashing. The nanoparticles within the tracks printed on the photographic paper exhibited significant melting after flashing sintering. This melting was due to very low thermal conductivity of the photographic paper and slow heat dissipation to the substrate and the surroundings. The nanoparticles on the PI substrate exhibited less appreciable melting due to greater thermal conductivity of the PI and fast heat dissipation to the substrate and the surroundings. 相似文献
94.
Wetting behaviors of hyperbranched polymer composites within ordered porous template under vibration
The wetting characteristics of hyperbranched polyesters (HBP) added cyclic olefin copolymer (COC) melt in microchannels of anodized alumina oxide (AAO) template were studied. The wetting displacements in microchannels were measured by scanning electronic microscopy (SEM). Compared with pure COC matrix, the composite flowed much longer in the microchannels under normal molding conditions. This may be attributed to the spherical shape of the HBP molecules. The flow study was extended by applying a series of high frequency vibration on the AAO template. Results show that vibration can enhance the wetting of the composite melts if phase separation does not occur. This paper provides useful information for micromolding based microfabrication, especially additives and vibration assisted micromolding. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers 相似文献
95.
A multi-scale finite element model (FEM) is developed to predict the post machined sub-surface damage in a particle reinforced metal matrix composite (MMC) subjected to laser-assisted machining (LAM). The MMC studied is an A359 aluminum matrix composite reinforced with 20% by volume fraction silicon carbide particles. In this model, molecular dynamics (MD) simulations are carried out to parameterize traction–separation laws for the aluminum–silicon carbide interface. The parameterized traction–separation laws are then input into a finite element model, in the form of a cohesive zone model to subsequently simulate the sub-surface damage. In this manner, the multi-scale hierarchical model successfully bridges the atomic, micro and macro scales. Average values of the predicted quantities are compared with experimental results, and the favorable agreement confirms the validity of the multi-scale FEM. 相似文献
96.
Chin‐Wan Lou Yuh‐Chyun Chiang Hsin‐Chung Cheng Ching‐Zong Wu Chiung‐Fang Huang Chih‐Wei Wu Yung‐Kang Shen Yi Lin 《Polymer Engineering and Science》2011,51(2):391-402
This work reports a novel and effective procedure for manufacturing the mold insert of microlens arrays. First, the microlens arrays master is formed using room‐temperature imprint lithography and photoresist reflow process. Next, electroforming is carried out to fabriccate the metal mold insert from the master. Finally, microinjection molding is used to replicate the molded microlens arrays. The 200 × 200 arrays of molded microlens, with a diameter of 150 μm, a pitch of 200 μm, and a sag height of 11.29 μm for polycarbonate (PC) material and 11.24 μm for polymethylmethacrylate (PMMA) material have been successfully fabricated. The moldability for PMMA material is better than PC material on molded microlens arrays. The average surface roughness of the molded microlens arrays is 4.53 nm for PMMA material and 4.81 nm for PC material. The mold temperature is the most important processing factor for the focal length and sag height of molded microlens arrays. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers. 相似文献
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99.
The development of precise definitions of security for encryption, as well as a detailed understanding of their relationships,
has been a major area of research in modern cryptography.
Here, we focus on the case of private-key encryption. Extending security notions from the public-key setting, we define security
in the sense of both indistinguishability and non-malleability against chosen-plaintext and chosen-ciphertext attacks, considering
both non-adaptive (i.e., ``lunchtime') and adaptive oracle access (adaptive here refers to an adversary's ability to interact
with a given oracle even after viewing the challenge ciphertext). We then characterize the 18 resulting security notions in
two ways. First, we construct a complete hierarchy of security notions; that is, for every pair of definitions we show whether
one definition is stronger than the other, whether the definitions are equivalent, or whether they are incomparable. Second,
we partition these notions of security into two classes (computational or information-theoretic) depending on whether one-way
functions are necessary in order for encryption schemes satisfying the definition to exist. Perhaps our most surprising result
is that security against adaptive chosen-plaintext attack is (polynomially) equivalent to security against non-adaptive chosen-plaintext
attack. On the other hand, the ability of an adversary to mount a (non-adaptive) chosen-plaintext attack is the key feature
distinguishing computational and information-theoretic notions of security. These results hold for all security notions considered
here. 相似文献
100.
Partner selection model and soft computing approach for dynamic alliance of enterprises 总被引:2,自引:0,他引:2
Partner selection is an active research topic in agile manufacturing and supply chain management. In this paper, the problem is described by a 0-1 integer programming with non-analytical objective function. Then, the solution space is reduced by defining the inefficient candidate. By using the fuzzy rule quantification method, a fuzzy logic based decision making approach for the project scheduling is proposed. We then develop a fuzzy decision embedded genetic algorithm. We compare the algorithm with tranditional methods. The results show that the suggested approach can quickly achieve optimal solution for large size problems with high probability. The approach was applied to the partner selection problem of a coal fire power station construction project. The satisfactory results have been achieved. 相似文献