[en] The history of experimental study on β-delayed proton decays in the rare-earth region was simply reviewed. The physical results of the β-delayed proton decays obtained at IMP, Lanzhou over the last 10 years were summarized, mainly including the first observation of 9 new β-delayed proton precursors along the odd-Z proton drip line and the new data for 2 waiting-point nuclei in the rp-process. The results were compared and discussed with different nuclear model calculations. Finally, the perspective in near future was briefly introduced

[en] This paper analyzes the standards of controlled door closing devices at home and abroad, compares the standards from test devices and items, and illustrates the backcheck function, delayed action and dead stop degree test in detail. In addition, experiments have been done to verify the influence of different door weights on closing time, opening and closing moment and efficiency. The results show that the door weight has significant influence on mechanical performance of controlled door closing devices. (paper)

[en] Our previous experimental method and results of (EC+β"+) decay for the medium-heavy nuclei "1"5"3Er, "1"5"7Yb, "2"0"9Fr, "1"2"8Ce, "1"3"0Ce, "1"2"8Pr, "1"3"0Pm and "1"4"0Tb have been briefly summarized. The observed low-lying states in their daughter nuclei and a 1 1/2"- isomeric state in "1"3"3Pr have been reviewed in a systematic way and compared with different model calculations. Finally, some questions have been put forward for further study and discussion. (author)

[en] In order to improve the measuring efficiency, a 'proton-gamma' coincidence technique in combination with a He-jet tape transport system was proposed and employed to identify the β-delayed proton precursors. The study of β-delayed proton decays near the proton drip line by using the 'proton-gamma' coincidence technique over the last 5 years at the Institute of Modern Physics, Lanzhou, China, was summarized. New β-delayed proton precursors ¹²¹Ce, ¹²⁵Nd, ¹²⁸Pm, ¹²⁹Sm, ¹³⁵Gd, ¹³⁷Gd, ¹³⁹Dy, ¹⁴²Ho, and ¹⁴⁹Yb in the rare-earth region along a speculated proton drip line were synthesized and identified for the first time. The β-delayed proton decays of ⁸¹Zr, ⁸⁵Mo, ⁸⁹Ru, and ⁹³Pd in T_z=1/2 series as well as ⁹²Rh in T_z=1 series were observed

[en] The previous experimental data on β-delayed proton decays of ¹⁴²Ho and ¹²⁸Pm were compared with a statistical-model calculation. As a result, the spins of both ¹⁴²Ho and ¹²⁸Pm were assigned as 5, 6, or 7. Nuclear potential-energy surface calculations were performed using the Woods-Saxon-Strutinsky method. The calculated results support the assignments of 7^- to ¹⁴²Ho and 6⁺ to ¹²⁸Pm

[en] The proton-rich isotope ¹³³Sm was produced via the fusion evaporation reaction ⁴⁰Ca + ⁹⁶Ru. Its β-delayed proton decay was studied by p-γ coincidence in combination with a He-jet tape transport system, and half-lives, proton energy spectra, γ-transitions following the proton emission, as well as β-delayed proton branching ratios to the low-lying states in the grand-daughter nucleus were determined. Comparing the observed β-delayed proton branching ratios with statistical model calculations, the best agreement is found assuming that only one level with the spin of 3/2 in ¹³³Sm decays or two levels with the spins of 1/2 and 5/2 decay with similar half-lives. The configuration-constrained nuclear potential energy surfaces of ¹³³Sm were calculated using the Woods-Saxon-Strutinsky method, which suggests a 1/2^- ground state and a 5/2⁺ isomer with an excitation energy of 120keV. Therefore, the simple (EC+β⁺) decay scheme of ¹³³Sm in Eur. Phys. J. A 11, 277 (2001) has been revised. In addition, our previous experimental data on the β-delayed proton decay of ¹⁴⁹Yb reported in Eur. Phys. J. A 12, 1 (2001) was also analyzed using the same method. The spin-parity of ¹⁴⁹Yb is suggested to be 1/2^-. (orig.)

[en] We report on the latest results of development on high-efficiency high-gradient superconducting radio frequency (SRF) cavities. Several 1-cell cavities made of large-grain niobium (Nb) were built, processed and tested. Two of these cavities are of the Low Surface Field (LSF) shape. Series of tests were carried out following controlled thermal cycling. Experiments toward zero-field cooling were carried out. The best experimentally achieved results are E_a_c_c = 41 MV/m at Q_0 = 6.5x10"1"0 at 1.4 K by a 1-cell 1.3 GHz large-grain Nb TTF shape cavity and E_a_c_c = 49 MV/m at Q_0 = 1.5x10"1"0 at 1.8 K by a 1-cell 1.5 GHz large-grain Nb CEBAF upgrade low-loss shape cavity.

[en] The history of experimental study on β-delayed proton decays in the rare-earth region was simply reviewed. The physical results of the β-delayed proton decays obtained at IMP, Lanzhou over the last 10 years were summarized, mainly including the first observation of 9 new β-delayed proton precursors along the odd-Z proton drip line and the new data for 2 waiting-point nuclei in the rp-process. The results were compared and discussed with different nuclear model calculations. Finally, the perspective in near future was briefly introduced

[en] We briefly reviewed and summarized the experimental study on β-delayed proton decays published by our group over the last 8 years, namely the experimental observation of β-delayed proton decays of nine new nuclides in the rare-earth region near the proton drip line and five nuclides in the mass 90 region with N∼Z by utilizing the p-γ coincidence technique in combination with a He-jet tape transport system. In addition, important technical details of the experiments were provided. The experimental results were compared to the theoretical predictions of some nuclear models, resulting in the following conclusions. (1) The experimental half-lives for ⁸⁵Mo, ⁹²Rh, as well as the predicted 'waiting point' nuclei ⁸⁹Ru and ⁹³Pd were 5-10 times longer than the macroscopic-microscopic model predictions of Moeller et al. [At. Data Nucl. Data Tables 66,131(1997)]. These data considerably influenced the predictions of the mass abundances of the nuclides produced in the rp process. (2) The experimental assignments of spin and parity for the drip-line nuclei ¹⁴²Ho and ¹²⁸Pm could not be well predicted by any of the nuclear models. Nevertheless, the configuration-constrained nuclear potential-energy surfaces calculated by means of a Woods-Saxon-Strutinsky method could reproduce the assignments. (3) The ALICE code overestimated by one or two orders of magnitude the production-reaction cross sections of the nine studied rare-earth nuclei, while the HIVAP code overestimated them by approximately one order of magnitude

[en] China is ranked first by greenhouse area in the world; pesticide application using knapsack electric sprayers is the main tool used in these settings to prevent and control plant diseases and insect pests. This is the first report of an exposure assessment for 60 greenhouse operators to the insecticide clothianidin when applied with knapsack electric sprayers. The commercial clothianidin formulation used in the field trials was a 20% suspension concentrate. The assessment was based on the whole-body dosimetry method and a personal air sampler fitted with an XAD-2 resin tube located in the operator’s breathing zone to monitor dermal and inhalation exposure, respectively. During application, the total dermal unit exposure was 598.71 mg/kg. The leg was the largest exposure area, accounting for about 53% of total dermal exposure. Meanwhile, inhalation exposure was only 0.50 mg/kg. The margin of exposure was much greater than 100 in all cases, indicating that the risk is controllable with the use of protection equipment and comparable to that of the manual application of treated soil.