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81.
We develop a new simulation method to study the dynamics of initial nucleation processes of photoinduced structural change of molecular crystals. In order to describe the nonadiabatic transition in each molecule, we employ a model of localized electrons coupled with a fully quantized phonon mode, and the time-dependent Schrödinger equation for the model is numerically solved. By applying a mean-field approximation in solving the Schrödinger equation, the calculation method is quite efficient on parallel computing systems. We show that coherently driven molecular distortion plays an important role in the successive conversion of electronic states which leads to photoinduced cooperative phenomena. 相似文献
82.
The effects of seed layers on the characteristics of rf-sputtered lead zirconium titanate thin films were investigated. Prior to sputtering, PbTiO 3 seed layers (100 nm) were deposited onto the Pt/Ti/Si and Pt/Si substrates by sol-gel (spin coating) processing method. Structure-property relation was studied as functions of substrate temperature and sputtering conditions. Special efforts were given in optimizing the deposition parameters to prepare the films in the perovskite phase without post deposition annealing. Dielectric constant and loss tangent of the films were in the range 800-950 and 0.04 -0.06, respectively. Remanent polarization and coercive field were 23.1 w C/cm 2 and 75kV/cm, respectively, for the films without PbTiO 3 seed layer, where as the corresponding quantities for in situ -deposited perovskite Pb(Zr, Ti)O 3 films on PbTiO 3 seed layer were 28 w C/cm 2 and 65 kV/cm, respectively. 相似文献
83.
Toshihiro Mukai Ken-ichiro Nishio Hidenori Komatsu Teppei Uchida Kyoko Ishida 《Energy Efficiency》2016,9(4):911-924
This paper presents results from a behavioral demand response trial targeted to both grid and residential peak hours, in which weekly feedback via paper-based reports, real-time feedback via an in-home display, 30-minute tiered rate, and email prompts are adopted to almost 230 residential customers of a condominium in Funabashi, a city located in Greater Tokyo. Through a randomized experiment, we find that the peak saving impact during grid peak hours (1–4 pm, weekdays only) was 11.6 %, given that all the four interventions provided all at once. In addition, the results show that the variation in peak saving effects by household characteristics exists, and the variation differs among packages of peak saving interventions. Furthermore, we analyzed how much informational elements in weekly reports are considered as useful by residential customers. These results suggest that feedback-based approaches for peak saving can promote households’ energy conservation behavior. 相似文献
84.
随着半导体制造业的不断发展,对现场浓度测量的需求也不断增加。化学品浓度细微变化都会对晶圆缺陷等级造成不良影响,最为重要的是会对产量产生影响。另外,减少液态化学品废弃物流,使其对环境的影响最小化面临着不断增长的压力。 相似文献
85.
86.
Fragmentation of the large subunit of ribulose-1,5-bisphosphate carboxylase by reactive oxygen species occurs near Gly-329 总被引:1,自引:0,他引:1
The large subunit (LSU) of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) in the illuminated lysates of wheat (Triticum aestivum L.) chloroplasts is broken down by reactive oxygen radicals into 37- and 16-kDa polypeptides. Analysis of the terminal amino acid residues of both fragments revealed that the C terminus of the 37-kDa fragment was Ser-328 and the N terminus of the 16-kDa fragment was Thr-330. Gly-329, which links the two fragments, was missing, suggesting that the fragmentation of the LSU in the lysates driven by oxygen-free radicals occurs at Gly-329. Purified rubisco, exposed to a hydroxyl radical-generating system, was also cleaved at the same site of the LSU. The cleavage site was positioned at the N-terminal end of the flexible loop (loop 6) within the beta/alpha-barrel domain, constituting the catalytic site of rubisco. The binding of a reaction intermediate analogue, 2-carboxyarabinitol 1,5-bisphosphate, to the active form of rubisco completely protected the enzyme from the fragmentation. The fragmentation was differentially affected by CO2, Mg2+, ribulose 1, 5-bisphosphate, or 2-carboxyarabinitol 1,5-bisphosphate. All these results indicate that the conformation of the catalytic site of the enzyme is involved as an important factor determining the breakdown of rubisco by reactive oxygen species. Reactive oxygen species generated at its catalytic site by a Fenton-type reaction may trigger the site-specific degradation of the LSU in the lysates of chloroplasts in the light. 相似文献
87.
A method to detect slip frequency from rotor slot harmonics of a three-phase squirrel-cage induction motor is proposed. The rotor slot harmonic voltage Is obtained by summing the three phase voltages, and after being sampled with a multiple of the stator frequency, it is changed into slip frequency waves, from which a voltage proportional to the slip frequency is obtained. Sophisticated sampling techniques allow elimination of the third harmonic voltage induced in the sum of the three-phase voltages and also allow reduction of time constant of the slip frequency detector. Expenmental results show that the slip frequency detector has a good linearity in the range of slip frequency of about -50 to +30 percent of the stator frequency. 相似文献
88.
Okabe Y Watanabe A Shingu H Kushibiki S Hodate K Ishida M Ikeda S Takeda T 《Meat science》2002,62(4):428-462
Relationships between α-tocopherol concentration in the muscle and development of lipid oxidation or volatiles in raw venison were studied. Fourteen Japanese Shika Deer (Cervus nippon) were fed various amounts (0–3.0 g of α-tocopheryl acetate per animal) during the different periods (0–37 days) and then M. longissimus thoracium et lumborum (LD muscles) with a range of α-tocopherol concentrations (4.1–15.1 mg/kg tissue) were obtained. For stabilizing the lipid during storage for 11 days under air, over ca. 9 mg of α-tocopherol per kg tissue were required based on levels of 2-thiobarbituric acid reacting substances (TBARS) numbers. Nine compounds were identified in headspace volatiles, and one of the volatiles was hexanal which has been recognized as off-flavour component. For depressing the hexanal evolution, at least ca. 9 mg of α-tocopherol per kg tissue were also required for 11 days’ storage. This value was much higher than other species. The reasons for higher requirement of α-tocopherol were possibly due to the higher concentration of unsaturated fatty acid and myoglobin in venison. 相似文献
89.
90.
A pneumatically actuated silicon microvalve applicable to integrated microfluidic systems is presented. All the ports of this microvalve are in-channel, and connectable to any surface fluid channels in microfluidic systems. This microvalve controls fluid flow by means of the controlled gap between glass and silicon diaphragm actuated by a control pressure. In addition, the diaphragm is also deformed by the outlet pressure of the microvalve. Due to the feature, this microvalve shows saturation of flow rate like MOSFETs operated at saturation region. The fabricated microvalve device was evaluated focusing on analogous relationship between MOSFET and the microvalve. Fluids such as air and DI-water were well controlled by the control pressure. Fluid starts to flow in the microvalve when the control pressure exceeds its "threshold pressure." Hysteresis due to sticking of diaphragm was not observed in the characteristics. Air flow rate of the microvalve was gradually saturated with the increasing of the outlet pressure as expected. Through the evaluation, analogous relationship between this microvalve and MOSFET has been experimentally demonstrated. 相似文献