Restoring soil quality is the main evaluation norm of the reclamation. In order to reveal the effects of mushroom waste on the quality improvement of reclaimed soil in coal mining areas, the physical, chemical and mic...Restoring soil quality is the main evaluation norm of the reclamation. In order to reveal the effects of mushroom waste on the quality improvement of reclaimed soil in coal mining areas, the physical, chemical and microbial characteristics of soil are studied. The results show clear improvement in the soil after using mushroom waste. Because of human cultivation and fertilization, cultivated soil after reclamation exhibits high comprehensive quality and the index of quality of surface soil reaches 0.64 and 0.73. The average index of surface soil quality is as high as 0.52 and 0.54. In comparison, the quality of reclaimed soil of forest land is low, with average index of 0.40. The effects of mushroom waste are mainly on the surface soil in the first 2 years after the application. After that period, with the decomposition of mushroom waste, soil quality index tends to be the same as the original soil. The quality of surface soil is higher than that of subsoil, especially after the application of mushroom waste, at which point the soil quality reaches a peak at about 15 cm. Cultivated soil after reclamation has great variance in quality, after the coefficient of 24.74%. Mushroom waste can reduce such variation, particularly with long-term use. The variance efficient falls to 3.59% after 3-year application.展开更多
Thermal mass is currently evaluated with "admittance" which is the ability of the element to exchange heat with the environment and is based on specific heat capacity, thermal conductivity and density. The aim of th...Thermal mass is currently evaluated with "admittance" which is the ability of the element to exchange heat with the environment and is based on specific heat capacity, thermal conductivity and density. The aim of this study is to evaluate the effect of thermal properties namely, density, specific heat capacity and thermal conductivity on thermal mass. The objective of the study is to carry out laboratory experiments by measuring such thermal properties of concrete mixes with various percentages of GGBS (ground granulated blast furnace slag), PFA (pulverized fuel ash), and SF (silica fume) and RCA (recycled coarse aggregates). The results obtained from these tests would contribute to the evaluation of how such thermal properties influence the thermal admittance and hence the thermal mass performance of sustainable concrete elements in a building system.展开更多
In this paper, concrete with limestone coarse aggregate was studied due to frost action in saline and nonsaline environments. The main focus is to explain the damaging formula of concrete with poor quality of limeston...In this paper, concrete with limestone coarse aggregate was studied due to frost action in saline and nonsaline environments. The main focus is to explain the damaging formula of concrete with poor quality of limestone aggregate in frost actions. All investigated concretes fulfill the recommendations of the European standard EN 206, Concrete--Specification, Performance, Production and Conformity limiting values for composition and properties of concrete (maximum W/C (water/cement) ratio, minimal class of compressive strength, minimal mass of cement and minimal percentage of entrained air). The damaging formula of the frost resistant concrete is studied through scaling test of concrete during freeze/thaw process, frost resistant test of coarse limestone aggregate and chemical analysis of limestone. Experiments results showed that there is a correlation between CaO/MgO ratio and Al2O3 of limestone and frost resistance of concrete, using chemical composition for determining potential ACR (alkali-carbonate reactivity) will indicate higher risk of damaging effect of concrete.展开更多
Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not r...Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not return a profit to the farmer due to the high cost of biochar. In this study biochar was modified through pre-treating the biomass and post-treating with phosphoric acid, minerals and different chemical fertilisers to study the effects of two new enhanced biochar fertilisers on the yield and quality of green pepper in a field experiment with 5 fertilisation treatments and 3 replications. The two new biochar fertilisers significantly (P 〈 0.05) increased the yield of green pepper (11.33-11.47 t ha-l), compared with the conventional chemical fertiliser (9.72 t ha-l). The biochar fertiliser treatments improved the vitamin C content of green pepper from 236.99 to 278.28 mg kg-1, and also significantly (P 〈 0.05) reduced the nitrate content from 132.32 to 101.92 mg kg-1, compared with chemical fertiliser. This study indicated that, compared to the use of conventional chemical fertiliser, all of the biochar fertiliser treatments could significantly improve the yield and quality of green pepper.展开更多
基金Supported by the National Natural Science Foundation of China (41171425)
文摘Restoring soil quality is the main evaluation norm of the reclamation. In order to reveal the effects of mushroom waste on the quality improvement of reclaimed soil in coal mining areas, the physical, chemical and microbial characteristics of soil are studied. The results show clear improvement in the soil after using mushroom waste. Because of human cultivation and fertilization, cultivated soil after reclamation exhibits high comprehensive quality and the index of quality of surface soil reaches 0.64 and 0.73. The average index of surface soil quality is as high as 0.52 and 0.54. In comparison, the quality of reclaimed soil of forest land is low, with average index of 0.40. The effects of mushroom waste are mainly on the surface soil in the first 2 years after the application. After that period, with the decomposition of mushroom waste, soil quality index tends to be the same as the original soil. The quality of surface soil is higher than that of subsoil, especially after the application of mushroom waste, at which point the soil quality reaches a peak at about 15 cm. Cultivated soil after reclamation has great variance in quality, after the coefficient of 24.74%. Mushroom waste can reduce such variation, particularly with long-term use. The variance efficient falls to 3.59% after 3-year application.
文摘Thermal mass is currently evaluated with "admittance" which is the ability of the element to exchange heat with the environment and is based on specific heat capacity, thermal conductivity and density. The aim of this study is to evaluate the effect of thermal properties namely, density, specific heat capacity and thermal conductivity on thermal mass. The objective of the study is to carry out laboratory experiments by measuring such thermal properties of concrete mixes with various percentages of GGBS (ground granulated blast furnace slag), PFA (pulverized fuel ash), and SF (silica fume) and RCA (recycled coarse aggregates). The results obtained from these tests would contribute to the evaluation of how such thermal properties influence the thermal admittance and hence the thermal mass performance of sustainable concrete elements in a building system.
文摘In this paper, concrete with limestone coarse aggregate was studied due to frost action in saline and nonsaline environments. The main focus is to explain the damaging formula of concrete with poor quality of limestone aggregate in frost actions. All investigated concretes fulfill the recommendations of the European standard EN 206, Concrete--Specification, Performance, Production and Conformity limiting values for composition and properties of concrete (maximum W/C (water/cement) ratio, minimal class of compressive strength, minimal mass of cement and minimal percentage of entrained air). The damaging formula of the frost resistant concrete is studied through scaling test of concrete during freeze/thaw process, frost resistant test of coarse limestone aggregate and chemical analysis of limestone. Experiments results showed that there is a correlation between CaO/MgO ratio and Al2O3 of limestone and frost resistance of concrete, using chemical composition for determining potential ACR (alkali-carbonate reactivity) will indicate higher risk of damaging effect of concrete.
基金financially supported by the Ministry of Science and Technology of China (Nos.2013GB23600666 and 2013BAD11B00)funded by the Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization,China+1 种基金supported by the grant of the Australian Research Council (No.LP120200418)Renewed Carbon Pty Ltd.,Australia and the project of DAFF Carbon Farming Futures-Filling the Research Gap,Australia (No.RG134978)
文摘Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not return a profit to the farmer due to the high cost of biochar. In this study biochar was modified through pre-treating the biomass and post-treating with phosphoric acid, minerals and different chemical fertilisers to study the effects of two new enhanced biochar fertilisers on the yield and quality of green pepper in a field experiment with 5 fertilisation treatments and 3 replications. The two new biochar fertilisers significantly (P 〈 0.05) increased the yield of green pepper (11.33-11.47 t ha-l), compared with the conventional chemical fertiliser (9.72 t ha-l). The biochar fertiliser treatments improved the vitamin C content of green pepper from 236.99 to 278.28 mg kg-1, and also significantly (P 〈 0.05) reduced the nitrate content from 132.32 to 101.92 mg kg-1, compared with chemical fertiliser. This study indicated that, compared to the use of conventional chemical fertiliser, all of the biochar fertiliser treatments could significantly improve the yield and quality of green pepper.