36Cl is one of the most interesting nuclides in accelerator mass spectrometry (AMS) measurements. The application of 36Cl has been widely applied in various fields. All most all of 36Cl AMS measurements at natural isotopic concentrations have yet been performed at tandem accelerator with 5 MV or higher terminal voltage. The measure improvement of 36Cl and other medium heavy isotopes performed at 3 MV in AMS facilities is one of the hottest topics in AMS measurements. In order to increase the suppression factor of 36S, the energy loss straggling and angular straggling of 36Cl and 36S ions in various counter gases (P10, isobutane and propane) were investigated. Some groundwater samples were measured with energy of 32 MeV, and the results were in good agreement with the result obtained with ion energy of 72 MeV. The results indicate that the approximate detection limit of 36Cl in 3 MV AMS facility is 36Cl/Cl=1×10-14 , and the uncertainty is 30% when the sample with isotopic ration 36Cl/Cl≈10-13.
WANG HuijuanGUAN YongjingZHANG WeiJIANG ShanMing He
Weak cross-Kerr media provides additional degrees of freedom of qubits in quantum information processing.In this paper,by exploiting weak cross-Kerr nonlinearity,we propose an optical implementation scheme of one-dimensional quantum random walks. The random walks are described by the interaction of single photons with cross-Kerr media.The proposed scheme can also be used to implement one-dimensional quantum random walks on an infinite line.