To discuss the pavement performance of basalt fiber-modified asphalt mixtures,the optimum dosages of asphalt and fibers are studied by the Marshall test and the rutting test.The results demonstrate that the optimum do...To discuss the pavement performance of basalt fiber-modified asphalt mixtures,the optimum dosages of asphalt and fibers are studied by the Marshall test and the rutting test.The results demonstrate that the optimum dosages of asphalt and fibers are 4.63% and 0.3%,respectively.Then the pavement performances of basalt（polyester,xylogen）fiber-modified asphalt mixtures are investigated through high temperature stability tests,water stability tests and low temperature crack resistance tests.It indicates that the pavement performances of the fiber-modified asphalt mixtures such as rutting dynamic stability,freezing splitting tensile strength,low temperature crack resistance and so on are improved compared with control asphalt mixture.The results show that the pavement performances of asphalt mixtures can be improved by fiber-modifiers.Besides,the improvement effects of basalt fiber are superior to polyester fiber and xylogen fiber.展开更多
In this paper, a theory of landslide model testing and application in Three Gorges reservoir area were introduced.Based on geo-mechanical model tests, the similarity ratio of similar material parameters, component of ...In this paper, a theory of landslide model testing and application in Three Gorges reservoir area were introduced.Based on geo-mechanical model tests, the similarity ratio of similar material parameters, component of similar material and the boundary friction coefficient of the 2D earth landslide model test were derived and stated by theoretical and experimental methods.A model test of the Qianjiangping landslide in Three Gorges reservoir area reveal a two-step trigger mechanism of coexistence between retrogressive landslide and thrust load caused land-slide.展开更多
Calcareous sand is a kind of special medium which is composed of calcium carbonate and other difficult soluble carbonate substances. Because of its rich in inner pore space and easy crashed,the mechanical property is ...Calcareous sand is a kind of special medium which is composed of calcium carbonate and other difficult soluble carbonate substances. Because of its rich in inner pore space and easy crashed,the mechanical property is very different from conventional quartz sand. Based on the compaction test and direct shear test of calcareous sand,by means of data fitting,the coupling relationship between compaction density and mechanical property under different water contents was obtained; meanwhile,the shear strength expression was built on the basis of the relationship between water content and dry density.展开更多
Chitosan is derived by deacetylation of chitin, a major component of the shells of crustacea such as crabs and shrimps. In this experiment using the Ames test, there was antimutagenic effect by the water-soluble chito...Chitosan is derived by deacetylation of chitin, a major component of the shells of crustacea such as crabs and shrimps. In this experiment using the Ames test, there was antimutagenic effect by the water-soluble chitosan that dissolved in hard water （CHW）. The Ames test was performed using Salmonella typhimurium TA98 and TA100. For the antimutagenic test, and the desmutagenic and bioantimutagenic tests, Trp-P-2, 2AA and AF-2 were used as mutagens. Tests for spontaneous mutation rate without mutagens were performed using S. typhimurium TA98 and TA100. When several concentrations of CHW were directly added to Minimal Glucose Plates, there were no changes in the number of His＋ revertants of TA98 and TA100. In desmutagenic and bioantimutagenic tests, the number of His^＋ revertants of TA98 and TA100 decreased. In the test for spontaneous mutation rate, the number of His＋ revertants of TA98 and TA 100 decreased slightly. When a concentration of CHW was added to examine antimutagenic effects, there was no change in the viable cell count of TA98 and TA100. From these results, AF-2 that is a direct mutagen may combine with CHW, and that may also be carrying out the inactivation. CHW possibly acts directly on the DNA by decreasing the rate at which mutation is caused to the strain＇s promutagens, Trp-P-2 and 2AA. This is evident from the decreased spontaneous mutation rate without a decreased viable cell count.展开更多
With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly intr...With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly introduces two methods to be respectively applied in the accelerated depreciatinn lesting for the luminous flex of LED lighting products and the life of outdoor LED-driving power, which can sharply shorten the time for lifetime lest. providing references for the LED lighting products＇ reliability evaluation.展开更多
文摘To discuss the pavement performance of basalt fiber-modified asphalt mixtures,the optimum dosages of asphalt and fibers are studied by the Marshall test and the rutting test.The results demonstrate that the optimum dosages of asphalt and fibers are 4.63% and 0.3%,respectively.Then the pavement performances of basalt（polyester,xylogen）fiber-modified asphalt mixtures are investigated through high temperature stability tests,water stability tests and low temperature crack resistance tests.It indicates that the pavement performances of the fiber-modified asphalt mixtures such as rutting dynamic stability,freezing splitting tensile strength,low temperature crack resistance and so on are improved compared with control asphalt mixture.The results show that the pavement performances of asphalt mixtures can be improved by fiber-modifiers.Besides,the improvement effects of basalt fiber are superior to polyester fiber and xylogen fiber.
基金Supported by the National Natural Science Foundation of China(50839004)Key Projects of the National Science & Technology Pillar Program in the 11th Five-year Plan(2008BAC47B03)Scientific Fund of Hubei Provincial Education Department(Q20081305)
文摘In this paper, a theory of landslide model testing and application in Three Gorges reservoir area were introduced.Based on geo-mechanical model tests, the similarity ratio of similar material parameters, component of similar material and the boundary friction coefficient of the 2D earth landslide model test were derived and stated by theoretical and experimental methods.A model test of the Qianjiangping landslide in Three Gorges reservoir area reveal a two-step trigger mechanism of coexistence between retrogressive landslide and thrust load caused land-slide.
文摘Calcareous sand is a kind of special medium which is composed of calcium carbonate and other difficult soluble carbonate substances. Because of its rich in inner pore space and easy crashed,the mechanical property is very different from conventional quartz sand. Based on the compaction test and direct shear test of calcareous sand,by means of data fitting,the coupling relationship between compaction density and mechanical property under different water contents was obtained; meanwhile,the shear strength expression was built on the basis of the relationship between water content and dry density.
文摘Chitosan is derived by deacetylation of chitin, a major component of the shells of crustacea such as crabs and shrimps. In this experiment using the Ames test, there was antimutagenic effect by the water-soluble chitosan that dissolved in hard water （CHW）. The Ames test was performed using Salmonella typhimurium TA98 and TA100. For the antimutagenic test, and the desmutagenic and bioantimutagenic tests, Trp-P-2, 2AA and AF-2 were used as mutagens. Tests for spontaneous mutation rate without mutagens were performed using S. typhimurium TA98 and TA100. When several concentrations of CHW were directly added to Minimal Glucose Plates, there were no changes in the number of His＋ revertants of TA98 and TA100. In desmutagenic and bioantimutagenic tests, the number of His^＋ revertants of TA98 and TA100 decreased. In the test for spontaneous mutation rate, the number of His＋ revertants of TA98 and TA 100 decreased slightly. When a concentration of CHW was added to examine antimutagenic effects, there was no change in the viable cell count of TA98 and TA100. From these results, AF-2 that is a direct mutagen may combine with CHW, and that may also be carrying out the inactivation. CHW possibly acts directly on the DNA by decreasing the rate at which mutation is caused to the strain＇s promutagens, Trp-P-2 and 2AA. This is evident from the decreased spontaneous mutation rate without a decreased viable cell count.
文摘With the application of energy-saving, environmental and durable LED lighting products, the reliability testing has become a pivot point for the large scale industrialization and popularization. The paper briefly introduces two methods to be respectively applied in the accelerated depreciatinn lesting for the luminous flex of LED lighting products and the life of outdoor LED-driving power, which can sharply shorten the time for lifetime lest. providing references for the LED lighting products＇ reliability evaluation.
