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Color of rosin is an important evaluation quality index. A process for preparing light-color rosin by adding different chemical additives in the reaction was studied. The results showed that the best light-color rosin can be produced by adding TM430 and TM923. Mechanism of decoloration was studied by ultraviolet spectra. The Gardner color of rosin was reduced from 7 to 2 and the acid value and softening point changed a little where the TM430 dosage of 0.2% based on the weight of the starting rosin, in atmospheres of nitrogen for protection, reaction time for 2h. The decoloration mechanism was analyzed with UV.The hydrogen atom generated by disproportionate catalytic reaction with TM430. The color substances in the raw rosin were reduced to colorless by hydrogen atom generated by catalytic of TM430.

ZnO; Quantum Dot-sensitized Solar Cell; CdSe; Photoelectrochemical property Abstract: ZnO nanotubes (NTs) were successfully fabricated with a hydrothermal method at low temperature. X-ray diffraction (XRD) and scanning electron microscopy (SEM) have been utilized to characterize the samples. The ZnO nanotubes, sensitized by CdSe, were used as a photoanode of a quantum dot sensitized solar cell, which generated a maximum power conversion efficiency of 0.95%.

In ground fracture region, Xi’an subway adopted segmented lining to adjust for the differential settlement. We applied three-dimensional finite difference method to simulate “plateau type” ground fractures. The conclusion is that segmented lining structure can restrain tunnel surrounding soil deformation near ground fractures effectively. Far away from the tunnel longitudinal axis, the surface settlement is consistent with free field. The change region of the soil pressure mainly distributes in 30m of ground fractures upward and 20m of ground fractures downward. The axial stress, major principal stress and minor principal stress on the inner side of lining with tunnel axis is more tensile than the outside one, and their tensile region are concentrating in the waist lining structure, their compression region are mainly distributing in vault and arch bottom. Based on the results, we suggest that the pulling reinforcing steel should be used in the waist lining structure.

Xi’an ground fracture, caused by the extraction of groundwater and the movement of fault under soil strata, is a geo-hazard. The movement of ground fracture originates the uneven settlement of upward block and downward block. In Xi’an ground fracture region, the segmented lining structure was adopted in subway tunnel to pass through the ground fracture, so as to adapt for the uneven settlement. Three-dimensional elastic-plastic finite difference method was applied to simulate the initial lining structure, second segmented lining structure, surrounding soils and ground fracture. The horizontal and vertical displacement of segmented lining structure, surrounding soils pressure and internal force of segmented lining structure in subway tunnel were analyzed by the calculation results. The knowledge on mechanical behavior of segmented lining structure passing through an active ground fracture and surrounding soils was shown as following. The relative vertical displacement between segmented lining structure sects beside the ground fracture increases remarkably with the movement of ground fracture, and the segmented lining structure located in upward displaceent block near ground fracture originates notable rotary. Tension or compression deformation occured in the deformation joint between adjacent segmented lining structures near the ground fracture.There was a significant change in the contact pressure of the first sect of lining structure in the upward displace block. Under the same uniform settlement at the bottom of upward diaplacement block, the relativly vertical displacemtn on the surfaceof ground fracture strata without tunnel equals 50cm, but the relativly vertical displacement between adjacent segmented lining structure at ground fracture is 18.2cm on the design level of arch top of lining strcutre. the maximum tensile stress of segmented lining structure is 2.02MPa, the maximum compressive stress of segmented lining is 3.49MPa. In conclusion, segmented lining structure can adapts to the uneven settlement caused by the movement of ground fracture. Though maximum tensile and compressive stress of sengmented lining structure passing through the active ground fracture is bigger than the general lining structure located in soils strata without the ground fracture, the segmented lining structure constructed by the steel fibre concrete can bear with the maximum tensile stress.

In this paper, polyester fibers (PET) were treated with low temperature plasma firstly. Then, these plasma treated PET fibers were coated with polypyrrole (PPy) by pyrrole deposition polymerization to impart conductive property to the fibers. Interfacial shear strength (ISS) between PET fiber and asphalt was measured by single fiber pull out test. XPS and SEM were used to characterize the fibers’ surface configuration and analysis the functional groups. The results show that plasma-treatment has a strong effect on the surface morphology, surface elements, electrical property and the ISS.

Crank block steering mechanism optimization, which is a nonlinear constrained optimization problem, is important for forklift truck to get preferable steering performance. Vector particle swarm optimization (VPSO) is a swarm intelligent algorithm proposed to solve constrained optimization problems with simple concept and easy implementation. Therefore, VPSO was proposed to optimize crank block steering mechanism of forklift truck in this paper, which will be intended for minimizing the maximal error of outer wheel steering angle, maximizing the minimal transmission angle and making the transmission capability of the force better. The experimental results obtained by VPSO are compared with the results obtained by enumeration algorithm which are reliable for optimization problems. The comparison results showed that vector particle swarm optimization can get same optimal results as enumeration algorithm in much less calculation times.

This paper reports a new kind Terahertz generator using tunable dual-wavelength generator based on MEMS technology, which are developed based on free-carrier effect (FCE) and thermo-optic effect (TOE) [1-3]. The approach provides a wide tuning range from 0 to 15 nm by adjusting the current of laser diodes and heating up common silicon Fabry-Perot (FP) external cavity. Compared to the conventional optical generation methods, this method has fast tuning speed (

A packaging architecture is developed for MEMS tunable laser (MEMS-TL). The hybrid integration of chips is realized under high accuracy thermal control and precise alignment. The thermal conductivity of the laser chip has been improved up to 60% by the proper substrate design of device and epi-down bonding method. Under the analysis of heat flux, we employ a thermo-electric cooler (TEC) to stabilize the temperature. The substrate is designed to accommodate gain chips with minimal active optical alignment, thus reducing the packaging cost. With this packaging scheme, the insertion loss is greatly induced less than 1 dB due to the advantages of horizontal and vertical alignment in optical fiber fastening and laser diode bonding.