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In order to predict the absorbing properties of absorbing material effectively in theory, effective media theory was applied to reduce the effective electromagnetic parameters of several composite absorbing agents under different volume ratio. The comparison with experimental data shows that this method can well forecast the absorbing properties of absorbing material. For practical absorbing agent and penetrating agent, this method can compute the optimal proportioning and material thickness.

One sol-gel method is explored to prepare red, green and blue (RGB) fluorescent dyes co-doped nanoporous silica at low temperature in air. All of the dyes covers blue-emitting 2, 5-bis (5-tert-butyl-2-benzoxazolyl)- thiophene (BBOT), green-emitting Coumarin 152A (Coumarin) and red-emitting Lumogen red R305 (Lumogen), contributing to the photoluminescence (PL) of the hybrid. As a key factor, the molar ratio of reactants TEOS/Dioxane/ H2O is 3:12:4 during the sol-gel process. The maximum doping concentration of dyes is the result of dyes dispersing into nanoporous silica, which supported by Infrared Spectroscopy (IR) and X-ray diffraction (XRD) technology. So this sol-gel preparation can enrich the inorganic luminescent materials at a simple style, especially for PL materials or electroluminescent (EL) materials in thin films state.

The pore structure of cement-based materials is closely related to the freeze-thaw resistance durability. And this paper focused on nanometer pores to verify the connection of freeze-thaw cycles in the nanometer pores with the structure deterioration and to explore the stress in the pore wall during the freeze-thaw process. And BET method was adopted to analyze the pore structure of the cement and results indicated the changing trends of parameters such as the pore volume, average pore size and surface area of specimens. Moreover, pore size distribution presented prominent fluctuations of pore sizes in the range of 0 ~ 20 nm, while the changes on the scale of 20 ~ 100 nm were limited.

The synthesis process of polycarboxylate superplasticizer (PCE) by bulk polymerization was investigated. Compared with BPO as initiator, PCE prepared by using AIBN as initiator exhibited better cement paste fluidities. PCE using isopentenyl polyethylene glycol (TPEG) or isobutenyl polyethylene glycol (IPEG) as macromonomer showed excellent fluidities and retaining properties at 80°C and 75°C, respectively. The fumaric acid was more suitable to copolymerize as the third monomer than maleic anhydride. The molecular weight measurements showed that the characteristics of molecular weight and its distribution for all the synthesized samples were in accordance with their cement paste fluidities. The solid-state PCEs can be conveniently dissolved into water to prepare PCE solution with arbitrary concentration, and still with good cement application performances.

Polycarboxylate superplasticizer (PCE) was synthesized in non-aqueous system to achieve the rapid transportation and convenient preparation. The results showed that, PCE using isopentenyl polyethylene glycol (TPEG) or isobutenyl polyethylene glycol (IPEG) as macromonomer exhibited excellent paste fluidities and retaining properties at 80°C and 75°C, respectively. Fourier Transform infrared spectroscopy (FTIR) measurement confirmed the polymerization between monomers. The synthesized PCE as solid state was dissolved into water to prepare the PCE solution, and its cement application performances were studied systematically. The results showed that PCEs with good paste fluidity retentions exhibited the longest final setting time and the shortest setting time interval. The hydration heat results showed that PCEs with good fluidity properties can significantly delay the hydration process and lower the hydration heat.

Usually there is a sliding between the contact surfaces of the connector, while the changes in temperature and humidity environment would affect the resistance of the connector contact materials. This paper studies the complicated effects of environment and sliding on the dynamic resistance of the contacts materials of Pd-Ni plated. Series of inspections and analytical research methods are introduced in this article. The surface morphology of specimens after damp heat cyclic test is observed by stereoscopic microscope and scanning electron microscope (SEM). Chemical constitution was examined by X-ray energy spectrum. The contact resistances were measured under the conditions of damp heat cycle by four-point method. The results show that the temperature and humidity environment and sliding has a more complex and significant impact on the performance of the contact materials than single-factors, and the tests are closer to the real working environment.

In order to keep the temperature of Light emitting diode (LED) lamp below some limitation, a finned plain-plate heat-pipe was presented and numerically investigated to predict heat transfer performance under natural convection. Two kinds of fin configurations were studied. It is found that 30° is the worst orientation for the fin configuration with the tops of every other two channels covered, while the worst orientation is around 60° for the fin configuration with channel tops opened. The thermal conductivity of fin material only has mild effect on the cooling capacity with 7 % difference when its thermal conductivity varies from 50 to 200 W/(m·k). The latter configuration has better thermal performance than the former at the same orientation, especially at relatively low inclined angle.