PHASE DIAGRAM OF SYSTEM NdCl_3-LiCl-KCl

The phase diagram of system NdCl_3-LiCl-KCl has been investigated by DTA.Six surfaces corresponding to the prhnary crystallization of NdCl_3,LiCl,KCl,γ-KCl·NdCl_3, β-3KCl·NdCl_3 and 2KCl·NdCl_3 respectively,eleven univariant lines related to the sec- ondary crystallization,two ternary eutectics E_1(70.5wt-% NdCl_3+8.0wt-% KCl,360℃) and E,(5.0wt-% NdCl_3+ 53.0wt-% KCl,355℃)and one ternary peritectic P (67.0wt-% NdCl_3+10.0wt-% KCl,375℃)were found.It is also chtrified that this study on the system NdCl_3- KCl differs from previous work in the two transition temperatures: e_1(77.0 wt-% NdCl_3,484℃),e_2(40.0wt-% NdCl_3,620℃),p (70.0wt-%NdCl_3,610℃),3KCl·NdCl_3(690℃)and two reactions: α-3KGl·NdCl_3β-3KGl·NdCl_3 (355℃) β-SKGl·NdCl_3γ-3KCl·NdCl_3 (450℃) The eutectic point e_5(31.0wt-%LiCl,460C)is determined for the pseudobinary system 3KCl·NdCl_3—LiCl.

NdCl_(3)-BaCl_(2)-NaCl三元体系相图的研究

借助于DTA和X射线衍射分析方法,研究了NdCl_(3)-BaCl_(2)-NaCl三元体系相图,发现本体系存在对应于NdCl_(3)、NaCl、α-BaCl_(2)、β-BaCl_(2)和Ba_(3)NdCl_(9)的5个液相面。6条二次结晶线,1个三元低共熔点E和三元转熔点P及一固相下形成的化合物。

Ln^(3+)在LnF_3-LiCl-KCl熔盐体系中的电化学行为

钍的分离和再利用是熔盐堆钍铀燃料循环的重要组成部分,钍与裂变产物特别是化学性质相似的镧系元素的分离是熔盐堆氟盐燃料处理的关键之一。利用循环伏安法和方波伏安法研究了773 K下多种镧系元素氟化物(w=3%)在LnF_3-LiCl-KCl熔盐中的电化学行为。研究结果表明:Ce^(3+)和Gd^(3+)在惰性电极上均一步还原为金属,Nd^(3+)则是通过两步反应还原为金属,而Sm^(3+)和Eu^(3+)只能还原为低价态的Sm^(2+)和Eu^(2+);Th和Ln在惰性金属阴极上的析出电位差ΔE均大于0.19 V,在LiCl-KCl熔盐体系中实现Th与Ln的电化学分离在理论上是可行的;与纯氯盐体系相比,少量F-的引入不会改变Ln^(3+)在惰性电极上的电极反应过程,F-的存在使得Ln^(3+)在LiCl-KCl熔盐中的活度降低,从而导致扩散系数减小。此研究结果为了解Th4+)和Ln^(3+)在含F-氯盐体系中的电化学行为和建立可行的分离方法提供了基础实验依据。

Effect of NdCl_3 on the Injury of Membrane and ABA Content under Osmotic Stress

Wheat seedlings grown in 0. 67 MPa Polyethylene glycol(PEG) , the relative water content(RWC) of leaves declined, the malondialdehyde(MDA) content and the permeability of plasma-membrane increased. The activity of superoxide dismutase (SOD) decreased, but that of peroxidase (POD) increased. At 3 h and 15 h osmotic treatment the abscisic acid(ABA) content showed two peaks respectively. When 0. 67 MPa PEG contained 35 4mol/L NdCl3 the RWC was higher than that of the control, the permeability of the plasma membrane and the MDA content were decreased. The activity of SOD of POD all increased by adding NdCl3. The ABA content showed only one peak at 24 h osmotic treatment, and the value of that peak declined obviously when treated with NdCl3.

Synthesis of NdCl_3-FeCl_3-Graphite Intercalation Compounds

NdCl3-FeCl3-graphite intercalation compounds were synthesized by means of molten salt-exchange method.Their layer structure and the relative content of the elements were investigated by X-ray diffraction, scanning electronmicroscopy and energy dispersive X-ray spectroscopy. The results show that the products are mixtures of 2, 3,4-stages,among them, the c-axis repeat distance, Ic, of stage-3 NdCl3-GIC is 1. 6536±0. 0024 nm. In addition, the mechanismof RECl3 intercalation reaction was discussed.

LIQUIDUS OF NdCl_3-MgCl_2-LiCl SYSTEM

The liquidus of ternary system NdCl_3-MgCl_2-LiCl has been determined by means of DTA.It was found that there are two surfaces corresponding to the primary crystallization of NdCl_3 and α-(MgCl_2,LiCl)respectively,and a univariant line related to the secondary crystallization with a minimum M(68.5 wt-% NdCl_3,2.7 wt-% MgCl_2,28.8 wt-% LiCl_2 441℃)in the system.

NdCl_3/MgCl_2 BISUPPORTED CATALYST FOR OLEFIN POLYMERIZATION

The NdCl_3/MgCl_2 bisupported catalyst was prepared by using NdCl_3 ,MgCl_2, (CH_3)_2(CH_2)_2 OH and TiCl_4. It is shown that the structure of bisupported catalyst was different from those of either NdCl_3 or MgCl_2 single supported catalyst. A peculiar type of kinetic curve for ethylene polymerization was found.

A Study on the Dissolving Loss of Nd in the NdCl_3-Containing Systems

The Dissolving loss of Nd in the systems NdCl_3-MCl_n(M=Li,Na,K,Ca,Sr,Ba;n=1 or 2) and the NdCl_3-rich NdCl_3-LiF motlen salts,and in the system of NdCl_3-(90 wt% KCl,10 wt%MCl_n) was determined.It was found that the dissolving loss of Nd (B_(Nd)) in the NdCl_3-KCl,NdCl_3-CaCl_2 and NdCl_3-(90 wt%KCl,10 wt%CaCl_2) melts is rather insignificant.The dissolving loss of Nd in the NdCl_3-KCl system increases with temperature,yet it is only 1/3 of that in pure NdCl_3 when the content of NdCl_3 was less than 50 wt% in the mixture.Addition of LiF to NdCl_3 can diminish the dissolving loss of Nd.The nature of interaction between metallic Nd and its salts was also discussed.

Structure model and synthesis of NdCl_3-FeCl_3-graphite intercalation compounds

The distribution of the elements and microstructure of NdCI3-FeCI3-graphite intercalation compounds (GICs) were shown by scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The results show that Nd element intercalates into graphite, forming NdCI3-FeCI3-GICs, and the distribution of Nd and Fe is nearly even. On the basis of the data, a structure model for RECI3-GICs was founded, and the characteristic layer distance and the index of interval energy were calculated. The calculated results agree with experimental ones, and the relative errors are ±2%. Thus it can be seen that the (111) face is optimal direction for intercalation reaction of TbCl3-LuCl3, and the (001) face is that for LaCl3-GdCl3, because of the lowest interval energy.