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The polymer-laced Cu-ZnO nanoparticles were successfully synthesized by one-pot non-aqueous nanoemulsion method with the use of PEO-PPO-PEO as the surfactant, C14H29CH(OH)CH2OH as the reducing agent, octyl ether as the solvent, Zn (acac)2 and Cu (acac)2 as precursors. The Morphology and structure of nanoparticles were analyzed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). UV-visible absorption spectroscopy (UV-vis) and photoluminescence spectrometry (PL) were employed to valuate the optical properties of the nanoparticles. The Cu-ZnO nanoparticles with well defined optical properties are promising for optical, catalytic and biomedical applications.

Swell-shrinking, crack development and over-consolidation are the characteristics of expansive soil, and it is an over-consolidation soil undergone dry-wet cycles. So there may be some faults to analyze expansive soil slope stability adopting the traditional strength criterion and calculation methods. In this paper, triaxial tests were carried out to obtain the relations between the parameters of shear strength and generalized plastic shear strain. The soil shear strength increases and then decreases along with the increasing of shear deformation due to soil over-consolidation. Moreover, the residual strength is achieved finally. The functions are applied in simulating the relations between the parameters and generalized plastic shear strain in order to analyze expansive soil slope stability.

FeAu/ZnO nanoparticles were successfully synthesized by nanoemulsion process with the use of poly (ethylene glycol)-block-poly (propylene glycol)-block-poly (ethylene glycol) as the surfactant. The characterization of the FeAu/ZnO nanoparticles was performed using X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and UV-visible absorption spectroscopy, showing that the polymer-laced nanoparticles reveal high crystallinity, excellent dispersibility and well defined optical performance. The process of solvent dispersion-collection of FeAu/ZnO nanoparticles indicates that the nanoparticles possess good magnetic property for applications.

Multi-functional CoNiAu nanoparticles were successfully synthesized via nanoemulsion method with the use of PEO-PPO-PEO as the surfactant, C14H29CH(OH)CH2OH as the reducing agent, Ni (acac)2, Co (acac)2 and Au (ac)3 as precursors. The characterization of the CoNiAu nanoparticles was performed using X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and UV-vis near IR spectrophotometer (UV-vis). The XRD and TEM analysis confirm the formation and structure of the nanoparticles. The UV-vis and VSM measurements display the optical and magnetic properties of the CoNiAu nanoparticles at the room temperature. The CoNiAu nanoparticles with the well defined optical and magnetic properties are promised for optical, magnetic, catalytic and biomedical applications.

This paper presents anexperimental study on reduction of NOx emission of a turbochargedengine fuelled with DME by means of EGR. Effects of EGR rate on engineefficiency and emission behavior was evaluated. The results show that the EGRcould be used as an effective way to reduce NOx emission. NOx isreduced almost linearly with increase of EGR rate. At low load condition, theNOx emission is reduced by 80% with 40% EGR rate without any economypenalty. At high load condition, the same substantial reduction of NOx couldbe achieved with only 20% EGR rate. While the HC and CO emissions are increasedwith increase of EGR rate. However, it is worth noting that EGR had a negativeeffect on fuel consumption at high load. Low EGR ratio should be taken at highengine load condition.

The expressions of crack spacing and width were deduced from the aspect of force-balance. The concept of maximum spacing and width of crack were put forward accordingly and they were verified and consistent with the site test results. Their relationships with soil parameters were discussed in detail. The new cracks do not appear until the spacing of adjacent cracks is greater than the maximum spacing, and the width of cracks will not be greater than the maximum width. The maximum spacing and width are judgments for describing and represent the final characteristic of cracks due to evaporation.

Hysteresis effect of contact angle has an important impact on liquid bridges between sphere particles. This effect is not limited to increasing liquid volume of fixed particles. The hysteresis effect of contact angle is expressed by fixed liquid volume while the two sphere particles are in relative movement. The hysteresis effect of contact angle on the liquid bridge is also significant. In this paper, the hysteresis effect of contact angle on capillary forces of liquid bridges is analyzed when the two sphere particles are in relative movement. Results indicate that contact angle hysteresis effects on capillary force are significant.