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Rational application of organic fertilizers is an effective approach to improve soil fertility, crop yield, and zero growth of chemical fertilizer in agricultural production. The rice variety 'Shennong9816' was planted in Shenyang, Liaoning Province, under seven different treatments: zero nitrogen fertilizer (CK), low nitrogen, 150 kg·hm -2 (LN), medium nitrogen, 240 kg·hm -2 (MN), high nitrogen, 330 kg·hm -2 (HN), medium nitrogen with replacement of chemical N by 10% organic manure (OMN 10 ), medium nitrogen with replacement of chemical N by 20% organic manure (OMN 20 ), and medium nitrogen with replacement of chemical N by 30% organic manure (OMN 30 ). The effects of different treatments on photosynthetic rate, nitrogen absorption, nitrogen use efficiency, and yield were examined and the optimal fertilization scheme was determined. The results showed that the photosynthetic rate, biomass and yield were increased with the increases of nitrogen application rate, while the nitrogen use efficiency was decreased significantly. Compared with the MN treatment, the photosynthetic rate of OMN 10 and OMN 20 in filling stage was increased by 22.9% and 9.9%, respectively. The yield of OMN 20 was increased by 3.8% compared to that of MN. The nitrogen agronomic efficiency and physiological efficiency of OMN 20 were significantly improved by 8.1% and 13.3%, respectively. Moreover, the nitrogen agronomic efficiency and physiological efficiency of OMN 20 were improved by 27.2% and 37.2% compared with the HN treatment. Thus, we concluded that the organic fertilizer replacement treatment could conserve soil fertility, achieve high yield and high nitrogen use efficiency, while reduce chemical nitrogen fertilizer application. The OMN 20 treatment was recommended as a fertilizer application model due to its superior performance among the seven treatments.

Monitoring of condensable particulate matter (CPM) emitted from stationary pollution sources has often been neglected. To reduce the emission of CPM, it is necessary to study its transformation rules in flue-gas cleaning devices. The results show that the wet flue gas desulfurization (WFGD) and wet electrostatic precipitator (WESP) have a good synergistic effect on the removal of CPM. The concentration of CPM in flue gas is higher than that of filterable particulate matter, but the concentration of total particulate matter (sum of the condensable particulate matter and filterable particulate matter) reaches ultra-low emission requirements. The organic mass concentration of CPM in the WFGD inlet and outlet is larger than that of inorganic components, which is equalized during the treatment of WESP. Based on measurements of the components and concentrations of water-soluble ions in the inorganic part of the CPM, PM 0.3 can be joined during the CPM trapping process and an acid mist is generated during the condensable particulate matter formation. The acid mist is strengthened through the treatment of WFGD and WESP. The experiment results also show that SO 4 2- is the main component of water-soluble ions in the inorganic part of CPM.

Weedy rice is an important germplasm source of rice, which has the characteristics of cold-, drought-, and barren tolerance. Taking 88 accessions of weedy rice and 4 varieties of cultivated rice in northern China as test materials, this paper studied the photosynthetic characteristics (photosynthetic rate, transpiration rate, and stomatal conductance), water physiological characteristics, and their interrelationships of weedy rice in northern China. There existed greater differences in the photosynthetic and water physiological characteristics among the weedy rice accessions, possessing abundant diversity. The photosynthetic rate of the accessions was from 12.47 micromol CO2 x m(-2) x s(-1) to 28.67 micromol CO2 X m(-2) x s(-1), and the instantaneous water use efficiency was from 1.39 mg x g(-1) to 3.40 mg x g(-1). Among the photosynthetic parameters, intercellular CO2 concentration had the smallest variable coefficient, while stomatal conductance had the largest one. The photosynthetic rate had significant conic relationships with transpiration rate and stomatal conductance, and had a linear relationship with intercellular CO2 concentration. The significant conic relationships also existed between the instantaneous water use efficiency and the transpiration rate and stomatal conductance. The excellent features of weedy rice could be used to improve the cultivated rice varieties.

Objective: To improve the biological property of artificial skin., Methods: We have ameliorated Hansburgh and Middelkoop's method of manufacturing artificial dermis. The type I collagenase and Dispase were used to isolated neonate prepuce' dermis fibroblast. The gel dermis was constructed by compounding the fibroblast and collagen swelling solution. The property of the collagen gel dermis was measured., Results: The neonate prepuce's dermis fibroblast had property of high proliferation, high activation of the dermis, and it could secrete abundant extracellular matrix (ECM)., Conclusion: The collagen gel dermis is an useful dermis substitute.