Bin Xiang

Effect of Heavy Metals on Brownfield Quality in Different Industries

With the rapid development of urbanization and industrialization in Chongqing, effect of heavy metals on brownfield has been paid more and more attention. 8 brownfields in steel industry, 15 brownfields in chemical industry, 18 brownfields in machining industry and 7 brownfields in pharmaceutical industry were selected as research objects, and eight heavy metals including mercury (Hg), lead (Pb), arsenic (Ar), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in soil were analyzed. Single factor pollution index (SFPI) and integral pollution index (IPI) was used to assess the pollution degree of these sites. The comprehensive results showed that the brownfields in the 4 studied industries had been affected by the heavy metals which produced in industrial activities. Machining industry had the greatest impact on the brownfield in Chongqing, also, the effect of chemical industry and steel industry to the soil were tremendous. Only pharmaceutical industry had little influence on the soil environment.

Scaling Mechanism of Heat Exchanger for Spent Sulfuric Acid Concentrating in Titania Production

The component and contents of scale sample on the graphite heat exchanger were analyzed by ED-XRF( Energy dispersive X-ray fluorescence spectrometer) and the component and contents of spent acid unconcentrated and concentrated were measured by AAS(atomic absorption spectrometer).In addition, the phase structure of scale sample was tested by XRD(X-ray diffraction) and the simulation experiment of spent acid concentrating was carried out to study the scaling mechanism in the laboratory. The results show that the main components of scale were Ca, Ti and Fe. The scaling might be induced by settlement of Ti oxide, and then Ca and Fe precipitate rapidly.

Soil Environmental Quality Assessment on an Abandoned Industrial Land

With the rapid development of urbanization and industrialization in China, whether the abandoned industrial land can be reused has become the focus of land planning. So soil environmental quality assessment on the abandoned land is necessary. In this paper, the land of a discarded chemical plant in Chongqing, China was chosen as the study object. The concentrations of heavy metal were studied. Single Factor Pollution Index (SFPI) and Integral Pollution Index (IPI) were applied to assess the degree of soil pollution. The results revealed that the abandoned industrial soil in this work was slight polluted and could only be planned for the 2nd type of land utilization, including green land, commercial land, public facilities land, etc.

Photo-Aging of Polyurethane Coating Based on TDI-TMP and N3390

The photoaging of polyurethane coating based on TDI-TMP and N3390 was conducted though UV exposure. The properties of studied polyurethane coatings, such as film thickness loss, gloss loss, discoloration and ultraviolet absorbance were examined at some aging intervals. In addition, scanning electronic microscopy (SEM) and Fourier transform infra-red spectroscopy (FTIR) were used to measure the morphology and chemical change of coatings before and after exposed in a UV lamp chamber. It was found that the addition of N3390 had a significant effect on the discoloration of polyurethane coating, and coating without N3390 had greater degradation. The above results suggested that a mixed curing agent system with a mass ratio of TDI-TMP to N3390 between 5:5 and 3:7 be a possible substitute of pure N3390 for weather resistance PU coatings.

Effect of Additives on Photo-Aging Performance of Polyurethane Coating

Polyurethane (PU) coatings with additives, such as UV-curing monomers and oligomers, ultraviolet absorbing (UVA) and hindered amine (HALS), were accelerated with Xenon lamp to study the effect of additives on photo aging performance of PU coatings. The ageing behavior of samples was evaluated with gloss-meter, chromatic meter, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM).The results indicated that the anti-aging of coating was improved by the synergy effect of 1.5wt.% HALS(Tinuvin 292), 3wt.% UV-curing resin (611B-85) and 1wt.% UVA(UV1130).

Different Curing Agents on the Photoaging of Polyurethane Coatings

In this paper, the artificial UV accelerated aging test was used to investigate the effect of curing agents including TDI-TMP prepolymer, N75, N3390 and IPDI propylene acid resin on the photoaging of polyurethane (PU) coatings. The thickness and gloss loss, color difference, as well as UV absorption of PU coatings were measured during the UV exposure, meanwhile FTIR and SEM were utilized to monitor the chemical and mophological change after UV exposure. The TDI-TMP prepolymer coatings showed the worst aging resistance and whilst the results of N3390 coatings are relatively good.

Heavy Metal Research on Sites of Former Machining Industry in Chongqing

Heavy metal pollution of soil has become a main obstacle to the change of land use for the former industrial site. In order to know whether the manufacture activities of machining industry has effect on the nearby soil, 18 former industrial sites were selected and eight heavy metals including mercury (Hg), lead (Pb), arsenic (Ar), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in soil were analyzed. The monitoring data was collected and analyzed by statistical methods. Besides, human influence degree and Nemerow Index were applied to assess the soil pollution. The result revealed that the average concentration of Hg, Pb, As, Cd, Cr, Cu, Ni, Zn were 0.12 mg/kg, 56.24 mg/kg, 4.86 mg/kg, 0.39 mg/kg, 184.32 mg/kg, 147.44 mg/kg, 46.84 mg/kg and 164.63 mg/kg, respectively. The concentration of Hg, Pb, Cr, Cu, Ni and Zn did not obey the normal distribution, however, As and Cd approximated normal.The soil was disturbed by the heavy metals produced in machining activities.

Computer Simulation of an Synthetic Ultraviolet Absorbent in the Interface of DMB and DMF

This work studies the aggregation of an synthetic ultraviolet absorbent, named 2-hydroxy-4-perfluoroheptanoate-benzophenone (HPFHBP), in the interface between two solvents which can not completely dissolve each other. The aggregation is studied by computer simulations based on a dynamic density functional method and mean-field interactions, which are implemented in the MesoDyn module and Blend module of Material Studios. The simulation results show that the synthetic ultraviolet absorbent diffuse to the interface phase and the concentration in the interface phase is greater than it in the solvents phase.