This paper presents a novel hybrid observer structure to estimate the lateral tire forces and road grip potential without using any tire–road friction model. The observer consists of an Extended Kalman Filter structure, which incorporates the available prior knowledge about the vehicle dynamics, a feedforward Neural Network structure, which is used to estimate the highly nonlinear tire behavior, and a Recursive Least Squares block, which predicts the road grip potential. The proposed observer was evaluated under a wide range of aggressive maneuvers and different road grip conditions using a validated vehicle model, validated tire model, and sensor models in the simulation environment IPG CarMaker®. The results confirm its good and robust performance.
In previous work, a microemulsion-based formulation approach yielded excellent laundry detergency with hydrophobic oily soils
hexadecane and motor oil. In this work, the same approach is used in detergency of triolein, which is a model triglyceride,
some of the most difficult oils to be removed from fabric. The linker concept was applied in formulation of the microemulsion
system. Three different surfactants were used: (i) dihexyl sulfosuccinate, an ionic surfactant with a moderate hydrophile-lipophile
balance (HLB); (ii) secondary alcohol ethoxylate, a lipophilic nonionic surfactant with a very low HLB; and (iii) alkyl diphenyl
oxide disulfonate (ADPODS), a hydrophilic anionic surfactant with a very high HLB. The phase behavior and interfacial tension
(IFT) of the surfactant systems were determined with different concentrations of ADPODS. The results indicate that as the
HLB of the system increases, a higher salinity is required to shift the phase transition from Winsor Type I to Type III to
Type II. The three formulations at different salinities were used in detergency experiments to remove triolein from polyester/cotton
sample fabric. The results showed that there were two peaks of maximum detergency in the range of salinity from 0.1% to 10%
NaCl. The higher the hydrophilicity of the system, the higher the salinity required for maximum detergency. The results of
the dynamic IFT and the detergency performance from two rinsing methods lead to the hypothesis that one of these maxima in
detergency results from a spreading or wetting effect. The other maximum in detergency is believed to be related to ultralow
IFT associated with oil/water middle-phase microemulsion formation. Triolein removal exceeding 80% was attained, validating
the microemulsion approach to detergency. 相似文献
This research reports on the adsorption and precipitation of mixtures of anionic and cationic surfactants having single and
twin head groups. The surfactant mixtures investigated were: (i) a single-head anionic surfactant, sodium dodecyl sulfate
(SDS), in a mixture with the twin-head cationic surfactant pentamethyl-octadecyl-1,3-propane diammonium dichloride (PODD)—adsorption
was studied on negatively charged silica; and (ii) a twin-head anionic surfactant, sodium hexadecyl-diphenyloxide disulfonate
(SHDPDS), and the single-head cationic surfactant dodecylpyridinium chloride (DPCI)—adsorption was studied on positively charged
alumina. Whereas the mixed surfactant system of SHDPDS/DPCI showed adsorption on alumina that was comparable to the of SHDPDS
alone, the mixed surfactant system of SDS/PODD showed increased adsorption on silica as compared with PODD alone. The adsorption
of the SDS/PODD mixture increased as the anionic and cationic system approached an equimolar ratio. Precipitation diagrams
for mixtures of single- and twin-head surfactant systems showed smaller precipitation areas than for single-head-only surfactant
mixtures. Thus, the combination of single- and double-head surfactants helps reduce the precipitation region and can increase
the adsorption levels, although the magnitude of the effect is a function of the specific surfactants used. 相似文献
Mixtures of anionic and cationic surfactants with single and twin head groups were used to solubilized styrene and ethylcyclohexane
into mixed micelles and adsolubilize them into mixed admicelles on silica and alumina surfaces. Two combinations of anionic
and cationic surfactants were studied: (i) a single-head anionic surfactant, sodium dodecyl sulfate (SDS), with a twin-head
cationic surfactant, pentamethyl-octadecyl-1,3-propane diammonium dichloride (PODD), and (ii) a twin-head anionic surfactant,
sodium hexadecyl-diphenyloxide disulfonate (SHDPDS), with a single-head cationic surfactant, dodecylpyridinium chloride (DPCl).
Mixtures of SDS/PODD showed solubilization synergism (increased oil solubilization capacity) when mixed at a molar ratio of
1∶3; however, the SHD-PDS/DPCl mixture at a ratio of 3∶1 did not show solubilization enhancement over SHDPDS alone. Adsolubilization
studies of SDS/PODD (enriched in PODD) adsorbed on negatively charged silica and SHDPDS/DPCl adsorbed on positively charged
alumina showed that while mixtures of anionic and cationic surfactants had little effect on the adsolubilization of styrene,
the adsolubilization of ethylcyclohexane was greater in mixed SHPDS/DPCl systems than for SHDPDS alone. Finally, it was concluded
that whereas mixing anionic and cationic surfactants with single and double head groups can improve the solubilization capacity
of micelles or admicelles, the magnitude of the solubilization enhancement depends on the molecular structure of the surfactant
and the ratio of anionic surfactant to cationic surfactant in the micelle or admicelle. 相似文献
Summary: Blends of different compositions were prepared from: a thermoplastic elastomer (EPDM), a low density polyethylene (PE), a polystyrene crosslinked with a small amount of divinylbenzene (PS‐co‐DVB) and an inorganic proton conductor: antimonic acid (HSb). The blends obtained were sulfonated heterogeneously with chlorosulfonic acid and were then structurally and electrically characterized by means of the following techniques: differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), crystallization kinetics under non‐isothermal conditions and complex impedance spectroscopy.
Heat capacity and thermal expansion measurements in composites have been relatively little used as research procedures. In recent times, however, they are beginning to be increasingly utilized in morphological studies. This motivated the application of both techniques to composites on the basis of polypropylene and sepiolite that had been surface treated with linear organic acids. Assessment of our results allows for the interference that the incorporation of these sepiolites produces important structural changes in the polypropylene containing them. These changes can be explained by the complex interface (mesophase) theory. 相似文献
The influence of potassium (K) on the hydrogen (H) adsorption on graphene (G) was studied by means of density functional theory with the generalized gradient approximation. The structural parameters, bonding and magnetic properties of one and two H atoms interacting with potassium doped graphene (H–K/G and 2H–K/G) are calculated for different energetically stable configurations. We found a charge transfer from K atom towards G even when the H atom pairs are adsorbed. This behavior is obtained for all the configurations studied here. The binding energy per H atom is greater in the most stable 2H–K/G arrangement than in both H–K/G and H/G systems. The present results suggest that the hydrogen atom binding energy on graphene layer could increase up to 82% due to the pre-adsorption of potassium. 相似文献