1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subs...1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subsidence,sediment supply(flow,type),the geometric characteristics of the upstream river,the energy(wave,展开更多
Nowadays, intensive breeding of poultry and livestock of large scale has made the treatment of its waste and wastewater an urgent environmental issue, which motivated this study. A wetland of 688 mz was constructed on...Nowadays, intensive breeding of poultry and livestock of large scale has made the treatment of its waste and wastewater an urgent environmental issue, which motivated this study. A wetland of 688 mz was constructed on an egg duck farm, and water hyacinth （Eichhornia crassipes） was chosen as an aquatic plant for the wetland and used as food for duck production. The objectives of this study were to test the role of water hyacinth in purifying nutrient-rich wastewater and its effects on the ducks＇ feed intake, egg laying performance and egg quality. This paper shows that the constructed wetland removed as much as 64.44% of chemical oxygen demand （COD）, 21.78% of total nitrogen （TN） and 23.02% of total phosphorus （TP）. Both dissolved oxygen （DO） and the transparency of the wastewater were remarkably improved, with its transparency 2.5 times higher than that of the untreated wastewater. After the ducks were fed with water hyacinth, the average daily feed intake and the egg-laying ratio in the test group were 5.86% and 9.79% higher, respectively, than in the control group; the differences were both significant at the 0.01 probability level. The egg weight in the test group was 2.36% higher than in the control group （P 〈 0.05）, but the feed conversion ratios were almost the same. The eggshell thickness and strength were among the egg qualities significantly increased in ducks fed with water hyacinth. We concluded that a water hyacinth system was effective for purifying wastewater from an intensive duck farm during the water hyacinth growing season, as harvested water hyacinth had an excellent performance as duck feed. We also discussed the limitations of the experiment.展开更多
Huainan mining area is located in the southern margin of the North China Plate, which is an important coal-producing base in the eastern part of China, its deep coal seam mining is threatened by karst water inrush dis...Huainan mining area is located in the southern margin of the North China Plate, which is an important coal-producing base in the eastern part of China, its deep coal seam mining is threatened by karst water inrush disasters in the bottom plate, analyzing hydrogeochemical characteristics and exploring its causes are an important prerequisite for preventing karst water hazards in the coal floor. This paper takes the karst water of the Taiyuan Formation in the lower part of the A-group coal seam of the Xieqiao-Zhangji-Gubei three mines in the Panxie mining area as the research object, and multivariate statistics, hydrochemical analysis were combined with hydrogeochemical simulation. The hydrogeochemical Component characteristics and cause of formation of the karst water-bearing system covered by huge thick unconsolidated layer are discussed. The results show that the cations are dominated by Na+ + K+, and the anions are mainly Cl−and HCO3−in the karst water in Taiyuan Formation in the study area, mainly affected by the dissolution of salt rock and the oxidation of pyrite, there are cations exchange and adsorption and desulfurization.展开更多
A series of compression tests were conducted on 150 groups of cement paste specimens with side lengths ranging from 40 mm to 200 mm. The specimens include cube specimens and prism specimens with height to width ratio ...A series of compression tests were conducted on 150 groups of cement paste specimens with side lengths ranging from 40 mm to 200 mm. The specimens include cube specimens and prism specimens with height to width ratio of 2. The experiment results show that size effect exists in the cubic compressive strength and prismatic compressive strength of the cement paste, and larger specimens resist less in terms of strength than smaller ones. The cubic compressive strength and the prismatic compressive strength of the specimens with side length of 200 mm are respectively about 91% and 89% of the compressive strength of the specimens with the side length of 40 mm. Water to binder ratio has a significant influence on the size effect of the compressive strengths of the cement paste. With a decrease in the water to binder ratio, the size effect is significantly enhanced. When the water to binder ratio is 0.2, the size effects of the cubic compressive strength and the prismatic compressive strength of the cement paste are 1.6 and 1.4 times stronger than those of a water to binder ratio of 0.6. Furthermore, a series of formulas are proposed to calculate the size effect of the cubic compressive strength and the prismatic compressive strength of cement paste, and the results of the size effect predicted by the formulas are in good agreement with the experiment results.展开更多
Effects of water to binder ratio (m(W)/m(B)), types and addition content of mineral admixtures ont he autogenous relative humidity (ARH) change of concrete resulting from self-desiccation were studies. The parameters ...Effects of water to binder ratio (m(W)/m(B)), types and addition content of mineral admixtures ont he autogenous relative humidity (ARH) change of concrete resulting from self-desiccation were studies. The parameters of coefficient of mineral self-desiccation-effect ka nd efficient water to binder ratio r(e) were proposed, and experimental results were fitted non-linearly and analyzed using these proposed parameters. The experimental results indicate that ARH reduction of concrete at different ages increases with the decrease of m(W)/m(B). The ARH changes laws of concrete with m(W)/m(B) lower than 0.4 can be expressed with a non-linear equation. The extent of the effect of types and addition content of mineral admixures on ARH reduction of concrete resulting from self-desiccation can be reflected by the non-linear equation with the parameter of efficient water to binder ratio r(e) effectively.展开更多
基于水波扩散效应,提出了一种水波中心扩散算法(water wave center diffusion,WWCD)。着眼解决函数极值优化问题,以某个局部最优解为中心点,由近至远、由密至疏产生多组扩散解进行迭代寻优。通过合理设计扩散解的扩散比例、选择比例和...基于水波扩散效应,提出了一种水波中心扩散算法(water wave center diffusion,WWCD)。着眼解决函数极值优化问题,以某个局部最优解为中心点,由近至远、由密至疏产生多组扩散解进行迭代寻优。通过合理设计扩散解的扩散比例、选择比例和跳跃比例等参数,提高算法的全局寻优效率,对比WWCD与6种智能优化算法极值优化问题的仿真结果,验证了前者在全局求解精度和收敛速度方面的优越性。聚焦雷达信号识别问题,WWCD优化支持向量机(support vector machine,SVM)关键参数进行雷达信号识别实验。仿真结果表明,通过本算法优化SVM关键参数进行雷达信号识别,可明显提高识别效率。展开更多
文摘1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subsidence,sediment supply(flow,type),the geometric characteristics of the upstream river,the energy(wave,
文摘Nowadays, intensive breeding of poultry and livestock of large scale has made the treatment of its waste and wastewater an urgent environmental issue, which motivated this study. A wetland of 688 mz was constructed on an egg duck farm, and water hyacinth （Eichhornia crassipes） was chosen as an aquatic plant for the wetland and used as food for duck production. The objectives of this study were to test the role of water hyacinth in purifying nutrient-rich wastewater and its effects on the ducks＇ feed intake, egg laying performance and egg quality. This paper shows that the constructed wetland removed as much as 64.44% of chemical oxygen demand （COD）, 21.78% of total nitrogen （TN） and 23.02% of total phosphorus （TP）. Both dissolved oxygen （DO） and the transparency of the wastewater were remarkably improved, with its transparency 2.5 times higher than that of the untreated wastewater. After the ducks were fed with water hyacinth, the average daily feed intake and the egg-laying ratio in the test group were 5.86% and 9.79% higher, respectively, than in the control group; the differences were both significant at the 0.01 probability level. The egg weight in the test group was 2.36% higher than in the control group （P 〈 0.05）, but the feed conversion ratios were almost the same. The eggshell thickness and strength were among the egg qualities significantly increased in ducks fed with water hyacinth. We concluded that a water hyacinth system was effective for purifying wastewater from an intensive duck farm during the water hyacinth growing season, as harvested water hyacinth had an excellent performance as duck feed. We also discussed the limitations of the experiment.
文摘Huainan mining area is located in the southern margin of the North China Plate, which is an important coal-producing base in the eastern part of China, its deep coal seam mining is threatened by karst water inrush disasters in the bottom plate, analyzing hydrogeochemical characteristics and exploring its causes are an important prerequisite for preventing karst water hazards in the coal floor. This paper takes the karst water of the Taiyuan Formation in the lower part of the A-group coal seam of the Xieqiao-Zhangji-Gubei three mines in the Panxie mining area as the research object, and multivariate statistics, hydrochemical analysis were combined with hydrogeochemical simulation. The hydrogeochemical Component characteristics and cause of formation of the karst water-bearing system covered by huge thick unconsolidated layer are discussed. The results show that the cations are dominated by Na+ + K+, and the anions are mainly Cl−and HCO3−in the karst water in Taiyuan Formation in the study area, mainly affected by the dissolution of salt rock and the oxidation of pyrite, there are cations exchange and adsorption and desulfurization.
基金Project(51408213)supported by the National Natural Science Foundation of China
文摘A series of compression tests were conducted on 150 groups of cement paste specimens with side lengths ranging from 40 mm to 200 mm. The specimens include cube specimens and prism specimens with height to width ratio of 2. The experiment results show that size effect exists in the cubic compressive strength and prismatic compressive strength of the cement paste, and larger specimens resist less in terms of strength than smaller ones. The cubic compressive strength and the prismatic compressive strength of the specimens with side length of 200 mm are respectively about 91% and 89% of the compressive strength of the specimens with the side length of 40 mm. Water to binder ratio has a significant influence on the size effect of the compressive strengths of the cement paste. With a decrease in the water to binder ratio, the size effect is significantly enhanced. When the water to binder ratio is 0.2, the size effects of the cubic compressive strength and the prismatic compressive strength of the cement paste are 1.6 and 1.4 times stronger than those of a water to binder ratio of 0.6. Furthermore, a series of formulas are proposed to calculate the size effect of the cubic compressive strength and the prismatic compressive strength of cement paste, and the results of the size effect predicted by the formulas are in good agreement with the experiment results.
文摘Effects of water to binder ratio (m(W)/m(B)), types and addition content of mineral admixtures ont he autogenous relative humidity (ARH) change of concrete resulting from self-desiccation were studies. The parameters of coefficient of mineral self-desiccation-effect ka nd efficient water to binder ratio r(e) were proposed, and experimental results were fitted non-linearly and analyzed using these proposed parameters. The experimental results indicate that ARH reduction of concrete at different ages increases with the decrease of m(W)/m(B). The ARH changes laws of concrete with m(W)/m(B) lower than 0.4 can be expressed with a non-linear equation. The extent of the effect of types and addition content of mineral admixures on ARH reduction of concrete resulting from self-desiccation can be reflected by the non-linear equation with the parameter of efficient water to binder ratio r(e) effectively.
