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In order to broaden the utilization of desulfurization gypsum in China and achieve the direct usage of desulfurization gypsum, in this paper, citric acid (CA), sodium citrate (SCA), sodium tripolyphosphate (STPP), Sodium hexametaphosphate (SP) were selected as retarder to modify desulfurization gypsum. The experiment results are as follows: the effect of SP, STPP, CA, SCA on desulfurization gypsum initial setting time is obvious; the turn is STPP> CA> SCA> SP; when the retarder dosage of STPP in desulfurization gypsum reaches 0.5%, the initial setting time can be extended to 210 min, the final setting time to 240min, which fully meets the demand of gypsum-site construction; inhibiting gypsum particles dissolution and preventing the growth of crystal nucleus are the fundamental reasons of STPP.

Lithium-ion secondary cell has high energy density, stable and high working voltage, wide working temperature and long working term. It is a safe and clean energy resource without pollution. At present, Lithium Hexafluorophosphate is used as conducting electrolyte lithium salt in lithium-ion secondary batteries. But Lithium Hexafluorophosphate as conducting electrolyte lithium salt has some disadvantages such as hydrolysis and instability. Lithium Bis (heptafluoroisopropyl) t-etrafluorophosphate Li [(C3F7)2PF4] was received by simons process from diisopropylchlorophosphane in this paper. As electrolyte of Li ion secondary cell, Li [(C3F7)2PF4] had lower vapor pressure than LiPF6 in the solvent in the same temperature, comparable conductivity and oxidation stability in the same concentration in room temperature. It was worth mentioning that Li [(C3F7)2PF4] has excellent stability towards hydrolysis. The synthesis process is safe and easily controlled.

Lithium-ion secondary cell has high energy density, stable and high working voltage, wide working temperature and long working term. It is a safe and clean energy resource without pollution. At present, Lithium Hexafluorophosphate is used as conducting electrolyte lithium salt in lithium-ion secondary batteries. But Lithium Hexafluorophosphate as conducting electrolyte lithium salt has some disadvantages such as hydrolysis and instability. Lithium Bis (heptafluoroisopropyl) t-etrafluorophosphate Li [(C3F7)2PF4] was received by simons process from diisopropylchlorophosphane in this paper. As electrolyte of Li ion secondary cell, Li [(C3F7)2PF4] had lower vapor pressure than LiPF6 in the solvent in the same temperature, comparable conductivity and oxidation stability in the same concentration in room temperature. It was worth mentioning that Li [(C3F7)2PF4] has excellent stability towards hydrolysis. The synthesis process is safe and easily controlled.

In order to broaden the utilization of desulfurization gypsum in China and achieve the direct usage of desulfurization gypsum, in this paper, Polycarboxylic acid water-reducer (HC), Naphthalene sulfonate formaldehyde polycondensate (NF) and Sulfonated melamine formaldehyde resin (SM) were selected as water reducer to modify desulfurization gypsum. The experiment results are as follows: SM water reducer has little effect on setting time of desulfurization gypsum, although it is helpful to increase the strength of the gypsum-sample, however, compared with HC and NF, it has no obvious effect. About HC water reducer, it has obvious effect on setting time of desulfurization gypsum, so does it to desulfurization gypsum strength, but, higher water using of normal consistency will do adverse effect on the whole with the increase of the dosage. NF water reducer has the similar effect on setting time and sample's strength on desulfurization gypsum with HC, but the dominant changes have no discipline among different mixing amounts with these two water reducer. Lower water using of normal consistency benefits the retention of the sample's strengths.

The acid dipping-plating pretreatment was applied on iron substrate prior to no-cyanide copper plating process. After being pretreated in dipping solution, the thin copper film formed on iron substrate which could change the cathode electronic potential and enhance the copper plating rate in the follow-up copper electroplating. As a comparation, the iron substrate was directly electroplated in another copper plating bath without dipping-plating pretreatment (DPr). The effects of temperature and electric current density on the copper plating rate were investigated in both process with DPr and process without DPr. And the mechanism was discussed.

Water-based infrared ray shielding coating, that is, nanometer metal oxide is added to the water-based paint, which has anti-IR features without affecting the transparency of the paint. In this paper, the nanometer oxides are prepared by sol-gel method, added into polypropylene sour. In order to improve the infrared ray shielding of the thin film, two kinds of nanometer oxides are added into the polypropylene sour with different volume ratios, the shielding performance of the paint is studied. Experimental results show: in the 8000 ~ 4000cm-1 range, the transmittances of infrared ray is 30% to 75%; in 4000 ~ 400cm-1 range, transmittances decrease significantly; 3% ZnO, 3% Fe2O3, 3% Y2O3, 2% Al2O3 are the best mass ratio of every single nanometer oxide; the infrared shielding rate of Fe2O3 and Y2O3 mixture with the volume ratio of 1 to 4 is better than Fe2O3 and Y2O3 single.

It is a method of preparing hypophosphorous acid with electrodialysis. It comprises Ti-PbO2 anode, an insoluble cathode and an aqueous solution of hypophosphite anions in six-compartment electrolytic cell. The direct current, through the insoluble anode to cathode in electrical contact with the aqueous solution to generate H+, forms hypophosphorous acid solution. In this paper, the best term of different factors about the experiment was studied. The best condition was to keep the NaH2PO2 concentration between 300 and 500g/L, current value 3.0A, reaction time 12-18 h. The process is simple, low cost and highly efficient, which is a cleaner production without waste residue and waste water.

Al-pillared rectorites (Al-REC) were synthesized from naturally occurring rectorite through exchange of interlamellar ions with hydroxyalumina polycations. Furthermore, Powder X-ray diffraction (XRD), Nitrogen adsorption-desorption isotherms, and Transmitting electronic microscopy (TEM) were applied in order to study the themal stability and hydrothermal stability of pillared materials. The Al-REC are thermally stable up to 800 °C. X-ray diffractograms of Al-REC calcined at 800 °C show a sharp and intense d001 peak, corresponding to a basal spacing of 2.75nm. In a 100% steam flow under atmospheric pressure at 800 °C for 20h, the characteristic d001 spacing of Al-REC decreases from 2.74 to 2.52nm, the sharp and intense d001 peak is still observed. And micropore area, mesopore volume and micropore volume retain 62, 33 and 67%, respectively, which affirms that this pillared clay has exceptional hydrothermal stability.