Excited states in 141Nd have been studied by using in-beam7-ray spectroscopic techniques with the heavy-ion induced 130Te(16O, 5n7)141Nd reaction. The 85 MeV 16O beam was provided by the HI-13 tandem accelerator in th...Excited states in 141Nd have been studied by using in-beam7-ray spectroscopic techniques with the heavy-ion induced 130Te(16O, 5n7)141Nd reaction. The 85 MeV 16O beam was provided by the HI-13 tandem accelerator in the China Institute of Atomic Energy. The previously reported 141Nd level scheme is significantly revised and extended up to much higher excitation energy as shown in Fig.l. Spins for many excited states in 141Nd展开更多
Soil stabilization has been found to be very effective in upgrading the bearing capacity of weak soils for construction purposes. The stabilizing agent, for cost efficiency, ought to provide a cheaper alternative to o...Soil stabilization has been found to be very effective in upgrading the bearing capacity of weak soils for construction purposes. The stabilizing agent, for cost efficiency, ought to provide a cheaper alternative to other possible processes. With the rapid industrialization efforts around the globe, enormous quantities of waste materials are generated and there has not been adequate mechanism for recycling and re-use of such wastes to reduce the consequent environmental problems and hazardous situations created as a result. The objective of the study is to upgrade expansive soils from Eke Obinagu, Ugwuaji in Enugu State and Egbede in Abia State Nigeria, as constructions material using RHA (rice husk ash). Expansive clay soils were mixed with this ash, remolded and tested to examine the effect on the OMC (optimum moisture content) and the CBR (California Bearing Ratio). The characterization of the soils was done in accordance with BS1377 and 1990b, with respect to their engineering properties which include OMC, MDD, Soaked CBR, Liquid Limit, Classification and Sieve Analysis. The rice husk was burnt and prepared in a cylindrical incinerator to form the ash. The results of classification showed A-7-5, A-6, A-2-7 soils for Eke Obinagu, Egbede and Ugwuaji, respectively. The CBR values showed increase from 5% to 29%, 7% to 13% and 5% to 23% for A-7-5, A-6 ~nd A-2-7 respectively at optimal value of 17.5% stabilization. There was also an appreciable increase in the OMC values from 15% to 33%, 14% to 25% and 15% to 31% for A-7-5, A-6 and A-2-7 soils respectively at 17.5% stabilization. Empirical models based on Scheffe's model were developed with the experimental results and the equations resulting from the second degree polynomials of Scheffe's models were solved using the least square method. The models developed showed close correlation with the experimental results for the A-7-5 and A-6 soils and will form good guide in pavement and foundation designs in the study areas.展开更多
文摘Excited states in 141Nd have been studied by using in-beam7-ray spectroscopic techniques with the heavy-ion induced 130Te(16O, 5n7)141Nd reaction. The 85 MeV 16O beam was provided by the HI-13 tandem accelerator in the China Institute of Atomic Energy. The previously reported 141Nd level scheme is significantly revised and extended up to much higher excitation energy as shown in Fig.l. Spins for many excited states in 141Nd
文摘Soil stabilization has been found to be very effective in upgrading the bearing capacity of weak soils for construction purposes. The stabilizing agent, for cost efficiency, ought to provide a cheaper alternative to other possible processes. With the rapid industrialization efforts around the globe, enormous quantities of waste materials are generated and there has not been adequate mechanism for recycling and re-use of such wastes to reduce the consequent environmental problems and hazardous situations created as a result. The objective of the study is to upgrade expansive soils from Eke Obinagu, Ugwuaji in Enugu State and Egbede in Abia State Nigeria, as constructions material using RHA (rice husk ash). Expansive clay soils were mixed with this ash, remolded and tested to examine the effect on the OMC (optimum moisture content) and the CBR (California Bearing Ratio). The characterization of the soils was done in accordance with BS1377 and 1990b, with respect to their engineering properties which include OMC, MDD, Soaked CBR, Liquid Limit, Classification and Sieve Analysis. The rice husk was burnt and prepared in a cylindrical incinerator to form the ash. The results of classification showed A-7-5, A-6, A-2-7 soils for Eke Obinagu, Egbede and Ugwuaji, respectively. The CBR values showed increase from 5% to 29%, 7% to 13% and 5% to 23% for A-7-5, A-6 ~nd A-2-7 respectively at optimal value of 17.5% stabilization. There was also an appreciable increase in the OMC values from 15% to 33%, 14% to 25% and 15% to 31% for A-7-5, A-6 and A-2-7 soils respectively at 17.5% stabilization. Empirical models based on Scheffe's model were developed with the experimental results and the equations resulting from the second degree polynomials of Scheffe's models were solved using the least square method. The models developed showed close correlation with the experimental results for the A-7-5 and A-6 soils and will form good guide in pavement and foundation designs in the study areas.