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1.
Precise measurement of magnetic moment of short-lived β-emitting nuclei12B ( I π=1+, T 1/2=20.18 ms)
Zhou Dongmei Zheng Yongnan Du Enpeng Xu Yongjun Zhu Jiazheng Yuan Daqing Wang Zhiqiang Luo Hailong Zuo Yi Ma Ruigang Duan Xiao M. Mihara M. Fukuda K. Matsuta T. Minamisono Zhu Shengyun 《中国科学G辑(英文版)》2004,47(5):531-539
The spin polarized β-emitting nuclei12B (I
π=1+,T
1/2=20.18 ms) were produced by the nuclear reaction11B(d, p)12B and by the selection technique of the incident deuteron energy and the12B recoil angle following the nuclear reaction. The nuclear magnetic moment of the short-lived nuclei12B was measured by β-NMR with the β-NMR and β-NQR setup established for the first time in China. The nuclear magnetic moment
of12B was determined to be μ=0.99993±0.00048 nm org=0.99993±0.00048 after the precise correction of the Knight shift. 相似文献
2.
N(1)取代5-氟尿嘧啶乙酸、5-氟尿嘧啶丙酸与Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Zn(Ⅱ)、Mn(Ⅱ)的配合物的合成及表征 总被引:1,自引:0,他引:1
合成了N(1)取代5-氟尿嘧啶乙酸、5-氟尿嘧啶丙酸与铜(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)和锰(Ⅱ)的十种金属配合物。通过元素分析、差热-热重分析确定了它们的化学组成,并对这些化合物进行了红外光谱、氢核磁共振谱,电子光谱的表征。讨论了各配合物中金属离子与配体的配位状态。在Cu(Ⅱ)配合物中,Cu(Ⅱ)是与配体的N3原子和C4上的羰基氧原子配位,其他金属配合物中,金属离子是与配体的C2的羰基氧原子和羧基配位。 相似文献
3.
4.
Shengyun Huang Andrea Cel Erwin Adams Zdenk Glatz Ann Van Schepdael 《Journal of separation science》2020,43(17):3565-3572
Capillary electrophoresis is a modern separation technique characterized by many benefits, which qualify it also for enzyme assays and the study of enzyme kinetics during drug development. Homogeneous or heterogeneous approaches can be followed for the enzymatic incubation. In this study, an immobilization procedure of aldehyde oxidase on magnetic particles was developed considering their integration with capillary electrophoresis. A number of magnetic nano/microparticle types were tested for this purpose, showing that aldehyde oxidase was most active when immobilized on bare silica magnetic nanoparticles. Primarily, the reusability of the enzyme immobilized on bare silica nanoparticles was tested. Three consecutive incubations with substrate could be performed, but the activity considerably dropped after the first incubation. One reason could be an enzyme detachment from the nanoparticles, but no release was detected neither at 4°C nor at 37°C during 5 h. The drop in enzymatic activity observed in consecutive incubations, could also be due to inactivation of the enzyme over time at given temperature. For the immobilized enzyme stored at 4°C, the activity decreased to 83% after 5 h, in contrast with a steep decrease at 37°C to 37%. 相似文献
5.
Linyan Yang Liangliang Xin Wen Gu Shengyun Liao Peiyao Du Jinlei Tian Yanping Zhang Rui Lv Xiaohua Wei Xin Liu Daizheng Liao 《中国化学》2014,32(3):227-232
A new coordination polymer, [Co2(L)2(4,4′‐bipy)]n·3nH2O ( 1 ) based on 5‐(3‐methyl‐5‐phenyl‐4H‐1,2,4‐triazol‐4‐yl)isophthalic acid (H2 L ) and 4,4′‐bipyridine (4,4′‐bipy) has been hydrothermally synthesized and characterized by single‐crystal X‐ray diffraction, XRPD, IR, and elemental analysis. Temperature‐dependent magnetic susceptibility and thermal degradation for 1 were also studied. The asymmetric unit of compound 1 consists of two crystallographically independent Co(II) ion, two L 2? ligand, one 4,4′‐bipy ligand, and three lattice water molecules. The 2D triangle networks were linked by the bridging 4,4′‐bipy ligand to give rise to a 2‐fold interpenetrated 3D architecture. The simplest cyclic motif of the 2D networks is a triangle ring consisting of three Co(II) cations and three L 2? ligands. So we can define Co(II) ions as 4‐connected nodes and the L 2? ligands as 3‐connected nodes. Thus, the 3D structure can be described as a 2‐fold parallel interpenetrated ins InS 3,4‐conn topology. 相似文献
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7.
The temperature dependence of the quadrupole interaction of111Cd in the In0.95 Ag0.045 Ga0.005 alloy is determined by the time differential perturbed angular correlation method from 77 to 422 K. The electric field gradients
produced by the lattice are derived. The temperature dependence of the electric field gradient is found to follow theT
3/2 law observed in In between 77 K and room temperature and to deviate from it at higher temperatures. The widths of the electric
field gradient distribution are 0.1147(259), 0.0924(340), 0.4954(601) and 1.344(175) at 77, 298, 373 and 422 K, respectively.
This illustrates that the alloy is well ordered at 77 and 298 K and that it becomes less ordered at 373 and 422 K. 相似文献
8.
Shilong Chen Dejun Zhang Shengyun Chen Tao Xia Qingbo Gao Yizhong Duan Faqi Zhang 《Chromatographia》2008,68(3-4):299-302
The Rhodiola L. genus (Crassulaceae) is one of the most important medicinal plant products used by Tibetans in Chinese phytotherapy. Fourteen species were examined for their content of salidroside. A considerable quantitative variation was observed using high-performance liquid chromatography and this depended on species and regional factors. It was found that all samples contained salidroside at concentrations ranging between 0.02 mg g?1 (R. sinuate) and 15.95 mg g?1 (R. sacra), respectively. The content of salidroside in R. sacra was significantly higher than in other popular medicinal plants of this genus. This finding indicated that there may be more Rhodiola species present in the Qinghai–Tibet Plateau which may be used as a potential source of salidroside. 相似文献
9.
The phase transition in the alloys Pd0.8 Si0.2 and Pd0.75 Si0.20 Ag0.05 have been investigated through the quadrupole interaction of111Cd impurities. The quadrupole interactions were measured by means of the TDPAC technique from room temperature up to about
870 K. The variation of the quadrupole interaction with temperature in the alloy PdSiAg shows aT
3/2 dependence below and above 629 K, with coefficientsB=5.43(25)·10−5 K−3/2 andB=3.70(15)·10−5 K−3/2, respectively. This demonstrates that the alloy undergoes a phase transition around 629 K. The existence of two electric
field gradients observed in the alloy PdSi,V
zz
(1)=3.47(54)·1017 V/cm2 andV
zz
(2)=2.29(36)·1017 V/cm2, indicates that there are two different111Cd sites. The corresponding fractionsf
1 andf
2 strongly depend on temperature. Below 520 K, most111Cd nuclei are subject to the higher EFGV
zz
(1) (f
1≈70%), whereas above 520 Kf
1 falls rapidly to zero andV
zz
(2) becomes dominant. The temperature dependences of thef
1 andf
2 reveal a picture of the phase transition between the two crystal structures. 相似文献
10.
K. Matsuta T. Minamisono M. Mihara M. Fukuda Shengyun Zhu Y. Masuda K. Hatanaka Daqing Yuan Yongnan Zheng Yi Zuo Ping Fang Dongmei Zhou T. Ohtsubo T. Izumikawa S. Momota D. Nishimura R. Matsumiya A. Kitagawa S. Sato M. Kanazawa M. Torikoshi T. Nagatomo Y. Nojiri T. Suzuki Xizhen Zhang J. R. Alonso T. J. M. Symons S. Kawasaki S. C. Jeong Y. Watanabe K. Minamisono 《Hyperfine Interactions》2013,220(1-3):21-28
We report our studies in various fields of Physics through nuclear moments utilizing the β-NMR technique, including material sciences, nuclear structures and fundamental symmetries. Especially, we focus on the recent progress in the studies on the electronic structure in Pt through Knight shifts of various impurities, lattice locations of impurities, electric field gradients, the analysis of nuclear spin in terms of its components, anomaly in the spin expectation value for 9C-9Li mirror pair, the G-parity conservation law, and the Ramsey resonance on UCN for future neutron EDM measurements. 相似文献