Advanced Materials Research Vols. 573-574

Abstract: Biogas Fertilizer nutrient contents are different with the different fermentation raw materials. This paper studied the migration and transformation of the nutrients in the raw materials-biogas fertilizer-soil-crop, summarized the correlation between fermentation materials and biogas fertilizer, the influence of biogas fertilizer on soil and crop nutrients. The results showed that: （1）The ratio of phosphorus and nitrogen content in raw materials and biogas fertilizers exceed the crop demand. （2）The inappropriate use of biogas fertilizer will result nitrogen/phosphorus nutrient in soil imbalance, contents of nitrite exceeded the soil standards and crops standards. To achieve the safe use of biogas fertilizer, it must carry out on biogas fertilizer standardization of production and scientific rational utilization.

Abstract: Changes in chemical, textural, and volatile flavor properties were investigated for mackerel fish (Scomberomorus niphonius) stored in cold rooms and freezers. Correlation and multivariate analysis showed a significant time-dependent relationship between TVBN/TMA (Y) and storage time (X) for fish stored in cold rooms, with R=0.996-0.997 values of Gompertz model (Y=a*exp(-exp(b-cX)), and there was a good linear relationship between TVBN and TMA. Combined with the textural properties, the polynomial fitting model (Y=a+bX+cX2+…, R=0.982-0.991) was applied and elucidated the correlation between hardness/springiness (Y) and TVBN (X), the rational function model (Y=(a+bX)/(1+cX+dX2), R=0.975-0.979) used for the chewiness (Y) and TVBN (X). The electronic nose analysis revealed that the variation of muscle volatile flavor compounds was found out along the PC1 to the right, and then along the PC2 to the upward and further to the downward based on the principal component analysis (PCA). Furthermore, the linear discriminant analysis (LDA) had better distinction effect for the changes of fish flavor than PCA. Results from this study suggested that the texture analysis in combination with electronic nose techniques might be utilized as a rapid expeditious process for predicting freshness and shelf life of the alive-storage fish or other aquatic products.

Abstract: Hydroponic system was used to investigate the interaction between different levels of Cd and Al in barley seedlings. The results showed that stress exposure promoted Al or Cd accumulation in plants, leading to strongly inhibited growth. Concentration- and tissue-dependent responses to Al or Cd stress in barley leaves, stems, and roots were found in four nutrient concentrations. Thus, stress generally inhibited Mg, Zn, and Ca absorption, but increased Fe accumulation and Ca translocation from roots to aboveground parts. Binary metal combinations significantly increased Al levels in plant parts, and aggravated growth inhibition as well as nutrients absorption disorder caused by Al treatments, especially the combination of 90 µM Al+5 µM Cd. By contrast, combined treatments decreased Cd concentration in plants, and the combinations of 10 µM Cd+Al alleviated Cd-induced growth and metabolism anomaly.

Abstract: The influence of photosynthetic bacteria (PSB) on the systerm of breeding chinese mitten crab was studied. Results showed: with the use of PSB, the vibrio bacteria reduced by over 10 times, the nitric bacteria rose 5 times, and the nitrous bacteria rose 1.9 times. The survival rate of the chinese mitten crab larvae were increased by 32.7%. The use of PSB in breeding chinese mitten crab system could improve bacteria population and water quality evidently, enhanced the carring capacity of the ecosystem.

Abstract: In the research, the dissolved oxygen, energy efficiency index, growth of aquatic worms and sludge reduction were determined and analyzed. The energy use of aeration and the growth of aquatic worms were investigated during the process of in-situ sludge reduction by aquatic worms. For the wastewater treatment system adding with adequate aquatic worms, the power consumption was not increased and the utilization rate of oxygen was improved. The growth of aquatic worms well fitted DoseResp function and the sludge production was reduced evidently. Results indicate that the wastewater treatment adding with aquatic worms utilizes aeration energy sufficiently and reduces sludge production effectively.

Abstract: Neutral red is mainly used to identify and detect the activated state of cells, which accumulates in the lysosomes of uninjured cells. In this paper the influence factors on microalgae of neutral red concentration, staining time, algal cell concentration and pH were studied, which revealed the optimized conditions. The maximum staining ratio occured after 8 min staining with 0.22 g•L-1 of neutral red at pH 7.3. The algal cell concentration had no obvious effect on staining ratio. The UV and UV/O3 process were also investigated for ballast water treatment using heterosigma akashiwo as an indicator. Compared with individual unit processes using UV, the inactivation efficiency of heterosigma akashiwo by the combined UV/O3 process was enhanced. The algae after treatment was unable to re-grow and it revealed that the algal activity assays can reflect the inactivation effect more correctly than cell density, which suggest the neutral red staining method has potential for viability detection of microalgae in ship’s ballast water.

Abstract: Phytoremediation is the use of vegetation for in situ treatment of contaminated soils, sediments, and water. It is best applied at sites with shallow contamination of metal pollutants. The term “assisted phytoextraction” usually refers to the process of applying a chemical additive to contaminated soil in order to increase the metal uptake by crop plants. In the process of phytoremediation, applying plant growth regulator can promote phytoextraction effects. This paper reviewed the effect of the plant growth regulator for the biological growth, plant transpiration and heavy metal stress. the increase in metal accumulation in upper parts of plant could be related to both the role of PGRs in the enhancement of plant resistance to stress (as toxic metals) and the increase in transpiration rate, i.e. flux of water-soluble soil components and contaminants by the regulation of stomatal opening.

Abstract: In order to explore decolorization mechanisms of sunflowers to different azo dyes, we made a mass balance on dye removal pathways. Though hydroponic experiment and desorption test, we measured and calculated the total removal ratio, the adsorption ratio and uptake ratio of dyes. Phytotoxicity of dyes to sunflowers also determined through normalized relative transpiration (NRT) and relative growth rate (RGR). The results showed that sunflowers can survive in 20, 40 and 80 mg/L Amido black (AB), Orange G (OG) and Methyl orange (MO). The average color removal ratio of AB, OG and MO in 15 days was 72.14%, 40.21% and 34.42%. The average adsorption ratio of AB, OG and MO was 3.36%, 4.74% and 22.49% respectively. The average uptake ratio of AB, OG and MO was 68.78 %, 35.46 % and 11.94 % respectively. It is concluded that the main pathway of removal of AB and OG by sunflowers is uptake and the main pathway of removal of MO by sunflowers is adsorption. The significant difference of the apparent TSCF of sunflower for AB, OG and MO showed that the removal ability of sunflower to azo dyes is related to the specific chemical and physical property of the dye.

Abstract: This study introduces a method of ammonia nitrogen removal from chlor-alkali industry wastewater by magnesium ammonium phosphate (MAP) precipitation. The effect of pH, reagent ratio and temperature were investigated. The pH was found to be the most significant factor. The optimal ammonia nitrogen removal ratio is about 46% under the condition of pH=10, reagent ratio n(Mg) : n(N) : n(P)=1.2 : 1.0 : 1.0 and temperature=35°C. According to this study, MAP precipitation method has the potential ability to be applied to remove ammonia nitrogen from chlor-alkali chemical industry wastewater.

Abstract: It is critical to properly dispose and utilize aged waste from informal landfill in China currently. Seed germination experiments using Lolium perenne L. were carried out to investigate terrestrial ecotoxicity of the aged waste. 20%, 80% and 100% of aged waste were added to the culture medium, and distilled water and soil were uded as contrast. The results showed that aged waste could substantially improve the seed germination of Lolium perenne L. , and didn’t show toxic effects. The optimal proportion of aged waste in mixing matrix (aged waste and soil) was 80%, whose seed germination potential presented 52.0% and 24.0% higher, and germination rate presented 34.3% and 20.9% higher than that of in distilled water and soil substrate respectively. Meanwhile, aged waste could also facilitate the growth of root and sprout remarkably. The seeds grown in the optimal aged waste matrix increased their root length, sprout length and fresh mass by 316.4%, 108.4% and 100.1% in comparison to those grown in distilled water respectively. And the root length, sprout length and fresh mass of Lolium perenne L. grown in the optimail aged waste matrix were 50.0%, 46.9% and 74.0% higher than that of the control groups using soil as culture medium respectively. The experimental results indicated that land application could be a feasible approach for matured aged waste recycling.