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111.
In the paper, we propose an adaptive rollover prevention controller for heavy vehicles. At first, a design method for an ideal vehicle model is proposed. The designed ideal vehicle model has the property that good rollover prevention performance can be assured even if the driver steering characteristics vary. If the behavior of the actual heavy vehicle tracks that of the designed ideal vehicle model, rollover prevention can be achieved. Therefore, next, to realize good rollover prevention, we propose an adaptive steering controller. In the heavy vehicle system using the controller, the actual heavy vehicle can track the ideal vehicle model. Then, rollover prevention can be achieved. Finally, to demonstrate the usefulness of the proposed controller, numerical simulations are carried out.  相似文献   
112.
In this paper, we propose an adaptive steering controller without using measurements of lateral velocity of vehicles. At first, we show a new dynamic expression suitable for the design of a stable adaptive steering controller without using the lateral velocity. Next, we develop an ideal vehicle model. In the designed ideal vehicle model, a good steering performance can be achieved even if the drivers’ steering characteristics vary. Finally, an adaptive steering controller is developed, so that the actual vehicles can track ideal vehicle model and realize good steering performance.  相似文献   
113.
In this work, we aimed to prepare a simple and an efficient adsorbent for the removal of toxic, cationic dye; malachite green (MG). We reviewed many previous studies and designed our adsorbent based on the rationale that (1) acidic groups containing monomers which are capable of making hydrogen bonds (or electrostatic interactions) with MG are very effective in adsorption and (2) π-π stacking enhances the adsorption capacity. We first synthesized an imidazole-acrylate adduct and used it for the preparation of photocured hydrogels. The imidazole-acrylate adduct was characterized by H NMR and FTIR spectroscopy. The effect of experimental conditions on the MG adsorption properties of the hydrogels such as the effect of pH, time and MG concentration were also investigated. Under the optimum conditions (pH = 6 and 220 min contact time) at room temperature, the maximum adsorption capacity was found as high as 714.28 mg/g. The results showed that the adsorption process of the optimum hydrogel, which can be used 4 times without a significant loss in its adsorption capacity, fits the Langmuir isotherm model. The hydrogel adsorbent displayed good selectivity and reusability.  相似文献   
114.
Quinaldine‐substituted poly(acrylic acid) (PQD) and its hydrogenated 1,2,3,4‐tetrahydroquinaldine derivative (PHQD) were prepared, and a cycle of hydrogen fixing and hydrogen evolution in and from the polymer, respectively, is described. A PQD layer coated on a carbon substrate was electrochemically reduced or hydrogenated using water as a hydrogen source, accompanied by the electrodeposition of nickel microparticles in the polymer layer, to convert PQD to PHQD. The conversion efficiency was enhanced by coating PQD on the substrate as a scaffold of nickel electrodeposition, in comparison with that of quinaldine and PQD dissolved in the electrolyte. The formed PHQD evolved hydrogen by simply warming it in water containing an iridium complex catalyst. Hydrogen fixing and evolution under mild conditions could suggest a new system of hydrogen carriers. © 2017 Society of Chemical Industry  相似文献   
115.
The deuterium (D) permeation behaviors for ion-damaged tungsten (W) by 3 keV D2+ and 10 keV C+ were studied. The D permeability was obtained for un-damaged W at various temperatures. For both D2+ and C+ implanted W, the permeability was clearly reduced. But, for the D2+ implanted W, the permeability was recovered by heating at 1173 K and it was almost consistent with that for un-damaged W. In the case of C+ implanted W, the permeability was not recovered even if the sample was heated at 1173 K, indicating that the existence of carbon would prevent the recovery of permeation path in W. In addition, transmission electron microscope (TEM) observation showed the voids were grown by heating at 1173 K and not removed, showing the existence of damages would not largely influence on the hydrogen permeation behavior in W in the present study.  相似文献   
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Coal tar pitch containing finely dispersed KOH was spun centrifugally, followed by stabilization through heating to 330°C under a (1:1) mixture of air and CO2 and carbonization/activation by heating to 850°C under CO2. The activated carbon fiber obtained possessed of a specific surface area of 491 m2g−1 and contained ca. 2% of K as K2CO3 over the peripheral region of fiber. The fiber showed high deodorization ability against 30 ppm of H2S gas in air at ambient temperature. H2S gas did not diffuse to the most interior parts of the fiber and was oxidized around outer regions of the fiber. Elemental sulphur was deposited in the fiber after H2S absorption. The deodorization mechanism was discussed. The role and action of the K2CO3 supported was explained.  相似文献   
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In this study, itaconic acid (IA) was grafted onto poly(vinyl alcohol) (PVA) with cerium(IV) ammonium nitrate as an initiator at 45°C. The grafted PVA was characterized with Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and differential scanning calorimetry. IA‐grafted PVA membranes were prepared with a casting method, and the permeation and separation characteristics of acetic acid/water mixtures were investigated with pervaporation (PV), evapomeation (EV) and temperature‐difference evapomeation (TDEV) methods. The effects of the feed composition, operating temperature, and temperature of the membrane surroundings on the permeation rate and separation factor for the acetic acid/water mixtures were studied. The permeation rates in EV were lower than those in PV, whereas the separation factors were higher. With the TDEV method, the permeation rates decreased and the separation factors increased as the temperature of the membrane surroundings decreased. The prepared membranes were also tested in PV, EV, and TDEV to separate the various compositions of the acetic acid/water mixtures (20–90 wt % acetic acid) at 40°C. The highest separation factor, 686, was obtained in TDEV with a 90 wt % acetic acid concentration in the feed. The activation energies of permeation in PV and EV were calculated to be 8.5 and 10.2 kcal/mol, respectively, for a 20 wt % acetic acid solution. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2322–2333, 2004  相似文献   
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