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A series of copolymers modified with oxidized starch containing maleic anhydride (MA), styrene sulfonic sodium (SSS) and oxidized starch (OS) were synthesized by the free-radical polymerization. The polymerization is initiated by ammonium persulfate. The effects of content of monomer and initiator, reaction time, reaction temperature on dispersion ability for Fe2O3 were investigated by single factor experiment. The dispersion ability for Fe2O3 measured through UV spectroscopy was studied. The experimental results show that the copolymer has good dispersion ability for Fe2O3 when the mass proportion of monomers is OS:SSS:MA = 1:3:1, the mass fraction of initiator in total monomers is 10 %, reaction time is 5 h, and the reaction temperature is 70 oC. The morphology of the copolymer was observed by scanning electron microscope (SEM). The experimental results indicate that the prepared copolymer modified with oxidized starch could be used in the corrosion inhibitor of high temperature water.

The corrosion inhibitor modified with acid activated attapulgite (CIATP) was prepared with acid activated attapulgite (HATP), styrene sulfonic sodium (SSS), maleic anhydride (MA) as monomers, water as solvent and ammonium persulfate as initiator. The effects of mass ratio of monomer, reaction temperature, the content of initiator and reaction time of preparing CIATP were investigated. The influences of the prepared CIATP concentration, time, pH and temperature of the system on the dispersing ferric oxide efficiency were also investigated. The obtained results showed that the prepared CIATP had excellent efficiency of dispersing ferric oxide, and nearly 98.98 % of dispersing ferric oxide efficiency was obtained. The experimental results indicate the corrosion inhibitor CIATP could be used in the corrosion inhibitor of high temperature water.

The inclusion complex formation between fluorescent sensor 3, 3’-benzidine/β-cyclodextrin derivative (BDCD) and pesticide carbaryl was studied and characterized by TEM, XRD and fluorescence spectroscopy. The stability constant and the stoichiometry of complex were determined. Based on the enhancement of the fluorescence intensity of carbaryl produced through complex formation, a new sensitive method for the determination of carbaryl was established. The linear relationship between the fluorescence intensity and carbaryl concentration was obtained in the range of 0.60-3.00 μmol/L with a correlation coefficient of 0.9946. The detection limit was 5.12 nmol/L. This method has been successfully applied to the determination of carbaryl pesticide residue in water, fruit and vegetable samples with satisfactory results, recoveries in the range of 94.12 % to 105.88 % were obtained. The method is rapid, simple, direct, economical, sensitive and useful for carbaryl analysis.

The host-guest inclusion complex formation between 3, 3’-benzidine/β-cyclodextrin derivative (BDCD) and pesticide carbendazim was studied and characterized by TEM and XRD. The result showed that inclusion complex had hydrophobic small-molecule fluorophores. The fluorescence titration was performed to calculate binding constant, sensitivity factor and limit of detection of the resulting complex. Based on the enhancement of the fluorescence intensity of carbendazim produced throught complex formation, a new sensitive method for the determination of carbendazim was established. A linear relationship was obtained between the fluorescence intensity and carbendazim concentration in the range of 3.57 and 17.83 μmol/L. The correlation coefficient, the lowest limit of detection and RSD were 0.9916, 15.51 nmol/L and 2.13%, respectively. This method has better anti-interference ability and stability. The proposed method have been successfully applied to the determination of carbendazim pesticide residues in water, vegetable and fruit samples with satisfactory results, recoveries in the range of 87.56 % to 104.04 % were obtained.

Adding biochar to agricultural soil has been suggested as an approach to enhance soil carbon sequestration. Biochar has also been used as a soil amendment to reduce nutrient leaching, reduce soil acidity and improve water holding capacity. Walnut shells and woody material are waste products of orchards that are cheap, carbon-rich and good feedstock for production of biochar. The effectiveness of biochar as an amendment varies considerably as a function of its feedstock, temperature during pyrolysis, the biochar dose to soil, and mechanical composition. Biochar was produced from pyrolysis of walnut shell at 900 °C and soft wood at 600 to 700 °C. We measured the effect of these different parameters in two types of agricultural soil in Jilin and Beijing, China, a silt clay loam and a sandy loam, on the soils’ particle size distribution and water retention characteristics. Biochars with two different doses were applied to each soil type. Soil field capacity and permanent wilting point were measured using a pressure plate extractor for each combination of biochar and soil type. The results show that the effect of biochar amendment on soil water retention characteristics depend primarily on soil particle size distribution and surface characteristics of biochar. High surface area biochar can help raise the water holding capacity of sandy soil.

According to the tectonic movement occurring in the South China Sea since the late Miocene and the sea level changes in Yingqiong Basin, Pearl River Mouth Basin, and global, combining with seismic reflection terminate characteristics, we divided Shenhu gas hydrate survey areas Pliocene strata into four sequences. According to the basic principles of the "outside-shape, internal-structure ,from seismic wave external geometry, supplemented by seismic physical attributes (amplitude, frequency, consistence),we identified the fill, mound, sheet, lens, sheet shape, wedge-shaped 6 categories, a total of 19 kinds of seismic facies in the study area. Contrasting to the drilling gas hydrate depth, the gas hydrate is mainly enriched around the slump deposits.

Unconfined compressive strength tests and calcium carbonate (CaCO3) quantitative chemical tests are conducted on artificially cemented sand which have different cement ratio (Cv) and curing time (t). Through the analysis of experimental results, the unconfined compressive strength (qu) of cemented sand are affected by curing time (t), cement ratio (Cv) and void ratio (η). Test results show that the longer the curing time (t), the lower the void/cement ratio (η/Cv) and the higher calcium carbonate/calcium hydroxide content ratio (CaCO3/Ca(OH)2 ratio or mC/mH), the higher the unconfined compressive strength (qu) of cemented sand. It is established the compressive strength equation based on the variables of cement ratio (Cv), void ratio (η) and curing time (t). By mC/mH-qu curve analysis, it is obtained the quantitative relation of chemical composition and mechanical strength.

TMS320F2812 is widely used in the design of embedded control system. Based on DSP TMS320F2812, the colliery high-voltage integrated protector which has setting protection, measurement, controlling and communication is developed. The design of AD module, CAN bus communication module and protection module of the integrated protector is elaborated. The structure design of its internal circuit and realization algorithms of part of modules are also given. Experimental results show that the protector achieves a good performance.

The establishment of eco-industrial parks can not only reduce the costs of waste disposal and the purchase of raw materials, but also has a positive impact on both economy and environment. By setting Shanghai as an example, a model of the eco-industrial park was described and the design plan and operating procedures of the park were provided in this paper. Then the benefits of this park were discussed. It may bring about some practicable approaches for the development of China’s eco-industrial parks through a specific analysis as well as the presentation of an operating model.

More frequently drying-rewetting is likely to be expected for soils this century, with strong effect on nitrogen transformation. Experiments were conducted in semi-disturbed soils which were incubated under 4 different moisture regimes (dry wet\constant wet\constant dry\constant flooded) for 71 d. The results show that the dry soil has a rapid NO3--N increase after rewetting. Drying-rewetting increases soil nitrification which shows a "pulse" increasing. The drying and rewetting soil has the highest nitrification intensity when the soil moisture content (g/g) ranging at 15.82% ~ 17.06%. Drying-rewetting contributes to the accumulation of NO3--N.

The successful cultivation of aerobic granular sludge used for simultaneous nitrogen and phosphorus removal in sequencing batch reactor (SBR) was performed using a synthetic domestic wastewater and conventional flocculent activated sludge as seeding sludge. The removal efficiency of sludge for chemical oxygen demand (COD),ammonia nitrogen and phosphate was 92.4%,88.1% and 95.9%, respectively. After screening, a strain was obtained with high efficient in nitrogen and phosphorus removal. By analyzing, the strain was identified as Raoultella ornithinolytica. After strain accumulation, the strain cultured at 30°C for 24h. The ammonia nitrogen and phosphate removal efficiency were 78.3% and 92%, respectively.

Stress-strain relationship of waste body under different side pressures, water contents and particle fractions are investigated in this paper. The bearing features of waste filled body of entry retaining besides gob-side entry retaining are: (1) filling waste gob-side entry retaining requires adequate horizontal restraint; (2) gangue water content has little effect on filling body intensity and waste in natural water content state can be used to fill in gob-side entry retaining; (3) stress and -strain relationship of waste body (grain size ranges from 0 to 10mm) is nonlinear. The bearing capacity can meet the requirement of beside gob-side entry retaining support. Based on above experimental results, the industrial roadway retained experiment is successful. The research results provide theory design basis for wide application.