Advanced Materials Research Vols. 113-116

Abstract: Wood is one kind of natural renewable eco-material. Laminated veneer lumber (LVL) is an engineered wood product made from veneers glued together with parallelly oriented grains under heat and pressure. This paper designed Poplar LVL production experiments under different process conditions, and measured the mechanical properties of poplar LVL specimens under different experimental conditions. In this study, grey theory was used to analyze the influences of different production processes on the mechanical properties, such as press duration, press temperature, pressure and adhesive spread. The results showed that, it is feasible that grey theory is used to analyze the influence level of production technology of poplar LVL on the mechanical properties. So this paper offered a new method to analyze and design the production technology of LVL.

Abstract: It is not easy to handle relativities of metals toxicology and ecological risk grades, especially, fuzzy in realization of soil heavy metal pollution, when the method suggested by Hakanson was used to assess ecological risk. To explore a better way to solve this problem, certainty in ecological risk grades was fuzzed through engineering fuzzy set theory, and a fuzzy mathematic model was built. The model was then applied in Xiaoqinling gold mining regional, which was selected as case study and where soil was polluted by heavy metals over decades, and its results were compared with that from Hakanson method. The results showed that the fuzzy mathematic model was a better way for ecological risk assessment of heavy metals in contaminated soil.

Abstract: It has been an inevitable requirement of taking a comprehensive evaluation for the power quality in the development process of electricity market. In the paper, it carried out an interval determination for the indicator data of power quality by the interval number estimation and defined each indicator weight by the entropy theory. Also it established an integral decision-making model of the interval number approximation. Then they made the all evaluation method more objective. The empirical shows that it can carry on a comprehensive evaluation for the power quality in the different periods by the evaluation method based on the entropy weight and interval number approximation, and it has a great practicality and feasibility.

Abstract: The dust storm is a kind of disaster weather with serious harmfulness. April 16~17, 2006 Beijing dust storm samples were collected far away from the highway. The processes of dust storm and materials of dust storm give us an opportunity to better understand the accumulation of loess and environmental influence of mankind to the desertification in arid to semiarid areas. We collected the dust storm samples, and carried out initial measurement using the luminescence research. Through the raw samples luminescence curve, the intensity of IRSL was very low. A number of tests were undertaken on quartz extracted from the sample prior to routine application protocol. From these results, we know that the equivalent dose and thermal transfer is sensitive to the rising preheat temperature. While De is unsensitive to the cutheat temperature (except for 280 °C). We chose a preheat temperature of 200 °C 10s and a cut heat of 160 °C in these tests. The results showed that the curve of equivalent dose for this dust storm had several peaks. It is a new evidence to prove that the dust source maybe originate from several regions.

Abstract: It is difficult to increase crude oil production for Daqing oil field by conventional technologies. In order to increase crude oil production, we make use of microbial enhanced oil recovery technology. The results showed that fluid production increased by 11 tons, oil production increased by 1.7 tons, water rate has decreased by 0.6 tons in oil reservoir after polymer flooding, North-2-4-P47 single-well daily. Microbial community diversity and dynamic change in oil reservoir after polymer flooding in Daqing Oil Field, North 2-4-P47 single-well in the process of microbial enhanced oil recovery was analyzed by PCR-DGGE. The results showed that the dominant microbes of North-2-4-P47 single-well are Acinetobacter johnsonii., Pseudomonas fluorescens., Pseudomonas sp., Bosea sp., Syntrophothermus lipocalidus., Aeromonas media. and some uncultured bacterium. Overall, microbial community diversity is abundant, and dynamic change of microbial community is also great in North-2-4-P49 single-well.

Abstract: To gain a better understanding of the mechanism and technology of microbial enhanced oil recovery, microbial community structure and diversity of reservoirs after polymer flooding in Daqing oil field at the Earlier Stage of microbial profile modification were studied. 16S rDNA gene clone library was used to assess the structure and diversity of microbial community. The results showed that the dominant microbes of the earlier stage of microbial profile modification are uncultured bacterium, comprising 88.6% of library clones. The cultured strains are composed of Epsilonproteobacteria(5.7%) , Gammaproteobacteria(4.7%) and Firmicutes (1%). Among the Epsilonproteobacteria, Sulfuricurvum accounts for 4.7% of the cultured strains of library clones and Arcobacter accounts for 1%. Besides, the dominant communities also include Pseudomonas and Moorella.

Abstract: To discuss optical properties of water body in Xiaojiang river backwater area after the early impounding stage of the Three Gorges Reservoir (TGR), the correlations between visible light attenuation coefficients (Kd(PAR)) and Secchi Disc transparency (SD), total particulate matters (TPM), dissolved organic carbon (DOC) and chlorophyll-a (Chla) were investigated, and spatiotemporal variations of Kd(PAR) and its influencing factors were analyzed. In the study area, there are no significant spatial variations of Kd(PAR), but the seasonal changes are obvious, with the highest value in winter and the lowest value in summer. Statistics analysis suggests that there are strong correlations between Kd(PAR) and SD, TPM, TIM, the value of R2 are 0.7791, 0.7285, and 0.7637, respectively. The relationship between Kd(PAR) and DOC is less significant(R2=0.1289). However, the correlation between Kd(PAR) and Chla was weak (R2=0.006). Further study shows that, the impact of total particulate matters on the optical properties of water body is as a result of both seasonal impoundment of the TGR and particular hydrological condition of Xiaojiang river basin.

Abstract: Based on the BECMP production line, this article introduced the main technological process for the production of BECMP pulp using aspen branch wood as the raw material. For better understanding of the new pulping method, Compared with the widely applied production line of P-RC APMP, the relevant pulping performances and operational efficiencies of BECMP were evaluated. The results showed that: using aspen branch wood in BECMP pulping was technically feasible, and it had more benefits as effective use of the lignocellulose raw material, energy saving, and reduction in water consumption. Most notably, the properties of the pulp met the requirements of APMP-based pulp mills, and simultaneously, its tensile strength was better than that of the APMP pulp.

Abstract: With the speed-up of urbanization, the number of motor vehicles has increased rapidly, which is the main urban air pollutant source because of too much emitted exhaust gas. Based on the motor vehicle exhaust emissions in Shandong Province in 2006, using trend extrapolation and scenario analysis, predict the motor vehicle exhaust emissions for future planning. The results show that the motor vehicles in 2015and 2020 are 27.52 million and 34.53 million, which is 1.9times and 2.38 times of the motor vehicles in 2006, respectively. For the specific air pollutants from motor vehicles exhaust in 2020, SO2, NOx, PM2.5 and PM10 will reach 28.4 thousand tons, 356.7 thousand tons, 10.8 thousand tons and 12.2 thousand tons, which will be 3 times, 1.2 times, 5 times and 5 times of the emissions in 2006. The urban air pollutions caused by motor vehicles exhaust will be very serious.

Abstract: Based on analysis of nitrogen transfer process, indoor experiments of nitrogen sorption, adsorption and leaching are done to study on the migration and transformation pattern of nitrogen. The spatial and temporal variation of ammonium and nitrate in the soil column is got. The influencing factors of nitrogen migration and transformation are analyzed from the sources of waste and hydrogeologic conditions. Corresponding prevention and control methods of groundwater nitrogen pollution are put forward.