N,N,N',N'-四丁基-3-氧-戊二酰胺辐解产物的研究Ⅱ液相辐解产物的定性分析

采用顶空固相微萃取（Headspace Solid-phase Microextraction,HS-SPME）技术结合气相色谱／质谱（GC／MS）联用方法对N,N,N’,N’-四丁基-3-氧-戊二酰胺（N,N,N’,N’-tertbutyl-30xa-pentanediamide,TBOPDA）的主要液相辐解产物进行定性研究,对影响HS-SPME的参数进行了优化。通过计算机谱库检索、标准物质对照和人工解析的方法确定了TBOPDA的六种液相辐解产物：（C4H9）2NH、（C4H9）3N、CH3CON（C4H9）2、HCON（C4H9）2、CH30CH2CON（C4H9）2、HOCH2CON（C4Hg）2;可能产物：HOCOCH2OCH2CON（C4H9）2或HCOCH2OCH2CON（C4H9）2,提出了TBOPDA的三种可能断裂方式。     

用气相色谱法测定N,N,N’,N’-四丁基-3-氧戊二酰胺在HNO_3中的溶解度

研究了用气相色谱法测定0.2 mol/LN,N,N’,N’-四丁基-3-氧戊二酰胺(TBOPDA)/40%辛醇-煤油中的TBOPDA在不同浓度HNO3中的溶解度的分析方法。首先取过量的0.2 mol/L TBOPDA/40%辛醇-煤油和不同浓度HNO3振荡40 min后,用甲苯萃取水相中的TBOPDA后进行气相色谱测量。采用选择性检测器氢火焰离子化检测器进行测定,0.2 mol/L TBOPDA/40%辛醇-煤油中的TBOPDA在1、2、3 mol/L HNO3中的溶解度分别为0.702、0.723、0.735 g/L。     

N,N,N’,N’-四丁基-3-氧-戊二酰胺辐解产物研究 Ⅰ.二丁胺的定性和定量分析

采用红外、顶空固相微萃取-气相色谱／质谱联用的方法，研究了萃取剂N，N，N'，N'-四丁基-3-氧-戊二酰胺(TBOPDA)的液相辐解产物，并通过与标准物质对照，确定TBOPDA的液相辐解产物中存在二丁胺和N，N-二正丁基甲酰胺。采用高效液相色谱、固相微萃取-气相色谱联用方法，定量分析了在辐照过程中TBOPDA的分解情况和二丁胺的产生情况，分别计算了两者的产额。提出了TBOPDA的3种可能断裂方式。     

N,N,N',N'-四丁基-3-氧-戊二酰胺的水解和辐解稳定性研究

N,N,N’,N’-四丁基-3-氧-戊二酰胺(TBOPDA)对锕系元素具有良好的萃取性能,为了考察TBOPDA稳定性,研究了温度、酸度和吸收剂量对TBOPDA萃取性能的影响。研究结果表明,该萃取剂在水溶液中具有较高的稳定性,当酸度为1mol／L,温度达到50℃时,铀的萃取性能没有变化;当酸度提高到5mol／L时,50℃条件下,铀的萃取分配比下降约37％。TBOPDA具有较好的辐解稳定性,当纯萃取剂的吸收剂量达到1MGy时,萃取分配比有明显下降;稀释剂的加入会使萃取剂的辐解稳定性下降。     

γ辐照对N，N，N’，N’-四丁基-3-氧-戊二酰胺萃取性能的影响

N，N，N’，N’-四丁基-3-氧-戊二酰胺(TBOPDA)对锕系和镧系元素具有较好的萃取性能和较高的辐照稳定性。本文主要研究了辐照对纯TBOPDA和稀释后的TBOPDA萃取性能的影响。研究结果表明，该萃取剂具有较强的辐照稳定性。纯萃取剂在辐照剂量达到1000kGy时，对铀的萃取分配比才有明显下降；达到100kGy时对铕的萃取分配比有明显下降。稀释剂的加入会使萃取剂辐照稳定性有所下降。     

N,N,N',N'-四丁基-3-氧-戊二酰胺辐解产物研究Ⅰ.二丁胺的定性和定量分析

采用红外、顶空固相微萃取-气相色谱/质谱联用的方法,研究了萃取剂N,N,N',N'-四丁基-3-氧-戊二酰胺(TBOPDA)的液相辐解产物,并通过与标准物质对照,确定TBOPDA的液相辐解产物中存在二丁胺和N,N-二正丁基甲酰胺.采用高效液相色谱、固相微萃取-气相色谱联用方法,定量分析了在辐照过程中TBOPDA的分解情况和二丁胺的产生情况,分别计算了两者的产额.提出了TBOPDA的3种可能断裂方式.     

γ辐照对N,N,N′,N′-四丁基-3-氧-戊二酰胺萃取性能的影响

N,N,N′,N′-四丁基-3-氧-戊二酰胺(TBOPDA)对锕系和镧系元素具有较好的萃取性能和较高的辐照稳定性。本文主要研究了辐照对纯TBOPDA和稀释后的TBOPDA萃取性能的影响。研究结果表明,该萃取剂具有较强的辐照稳定性。纯萃取剂在辐照剂量达到1000kGy时,对铀的萃取分配比才有明显下降;;达到100kGy时对铕的萃取分配比有明显下降。稀释剂的加入会使萃取剂辐照稳定性有所下降。     

荚醚N,N,N'',N''-四丁基-3-氧-戊二酰胺 (TBOPDA)气相辐解产物的研究

研究了荚醚N，N，N′，N′－四丁基－3－氧－戊二酰胺（TBOPDA）的辐照气体产物（氢气、烷烃及烯烃气体），并将其产额与TBP的辐解气体产物产额对照。结果发现，其气体辐解产物产额明显低于TBP的气体辐解产物产额，并对其氢气生成机理进行了探讨。     

N,N,N′,N′-四异丁基-3-氧戊二酰胺对钼(Ⅵ)的萃取

研究了N，N，N′，N′－四异丁基－3－氧戊二酰胺（TiBOPDA)-40%正辛醇／煤油溶液从HNO3溶液中萃取Mo(Ⅵ）的行为。实验结果表明，温度对Mo(Ⅵ）的萃取分配比影响很小，萃取过程无明显热效应。在HNO3浓度为1mol/L时，Mo(Ⅵ）以MoO2^2 形式被萃取，MoO2(NO3)2与TiBOPDA形成配位比为1：2的配合物，TiBOPDA萃取Mo(Ⅵ）为中性配合萃取。文章给出了萃取平衡方程式。     

N,N,N,,N,-四己基丁二酰胺萃取铀、钍及硝酸的机理

合成了 N,N,N?N?四己基丁二酰胺(THSA)。以正十二烷为稀释剂研究了THSA萃取硝酸的平衡,认为在低酸度下主要形成THSA·HNO3加合物,在高酸度下主要形成加合物THSA·HNO3和THSA·(HNO3)2;还研究了THSA从硝酸介质中萃取铀、钍的机理,通过考察 HNO3浓度、THSA浓度及温度对铀和钍分配比的影响,得出了萃合物的组成为UO2(NO3)2·THSA和Th(NO3)4·2THSA,并计算出萃取反应的表观平衡常数及热焓。实验结果表明THSA具有较强的对铀、钍萃取能力,并有望实现铀、钍分离。     

乙羟肟酸消除Zr界面污物的研究

研究在模拟高放废液中加入乙羟肟酸（AHA）以消除酰胺荚醚（TBOPDA）萃取模拟高放废液过程中的界面污物。萃取实验结果表明：在模拟高放废液中加入AHA可显著降低Zr（Ⅳ）在两相中的分配比，此时，Pu（Ⅳ）的分配比仍足够大，它不影响TBOPDA对Pu（Ⅳ）的回收。反萃实验表明：在所研究的反萃条件下，1级反萃即可有效反萃TBOPDA有机相中的Zr（Ⅳ）；3次错流反萃可有效反萃TBOPDA有机相中的Pu（Ⅳ）；反萃液中加入AHA对Am（Ⅲ）的累计反萃率影响很小；提高反萃液的酸度可抑制TBOPDA有机相中Am（Ⅲ）的反萃。     

Determination of 14N(n,2n)13N Reaction Cross Section for 14.7 MeV Neutrons

The cross section for the ¹⁴N(n, 2n)¹³N reaction in respect of 14.7 MeV neutrons has been determined. In this experiment, the ²⁷Al(n,p)²⁷Mg reaction was selected as reference standard, for its generation of the nuclide ²⁷Mg which has a half-life very close to that of ¹³N. The full-energy peaks of the γ-ray spectrum obtained by multi-channel pulse height spectrometer was analyzed with γ-ray energy resolution determined by means of normal probability plots.

The resulting value for the cross section is 8.2±1.1 mb, which is in remarkably good agreement with the value reported in literature.     

Measurement of (d,p) and (d,α) differential cross-sections for N

The differential cross-sections for ¹⁴N(d,p₀)¹⁵N, ¹⁴N(d,p₁₊₂)¹⁵N, ¹⁴N(d,α₀)¹²C and ¹⁴N(d,α₁)¹²C have been measured in the energy range from 0.7 to 2.2 MeV at the laboratory angle of 150°. The obtained results are compared with data published in the literature. Discrepancies between new and previously acquired data are discussed. The cross-sections measured in the present work were uploaded to the IBANDL data base <http://www-nds.iaea.org/ibandl/>.     

Precise Intensity Measurements in the 14N(n, γ)15N Reaction as a γ-Ray Intensity Standard up to 11MeV

The main γ-ray intensities in the ¹⁴N(n, γ)¹⁵N reaction were determined at an accuracy of 0.3–1.0% based on the intensity balance principle. Measurements were performed at the supermirror neutron guide tube at the Kyoto University reactor (KUR). A liquid nitrogen target and a deuterated melamine (C₃D₆N₆) one were used. We prepared a full-energy-peak efficiency curve by combining the measured and calculated efficiency curves. The previous values widely used as intensity standards agreed with the present results within 4–5% in the 2–11 MeV region, but the ratio to the present values showed a monotonic decrease with the increase in _-ray energy. The results reported by Belgya in 2006 agreed with the present one within 2–3% in the 2–8MeV region; nevertheless, the ratio showed a small oscillation versusγ-ray energy.     

吉西他滨-~(13)C,~(15)N_2及其代谢产物的合成

以自制的尿素-~(13)C,~(15)N_2为前体,与3-乙氧基丙烯腈反应制备胞嘧啶-~(13)C,~(15)N_2,用BSA保护后,经与2-脱氧-2,2-二氟-D-赤式-五呋喃糖-3,5-二苯甲酯-1-甲磺酸酯反应生成2′,2′-二氟-2′-脱氧胞嘧啶核苷-3′,5′-二苯甲酸酯-~(13)C,~(15)N_2,分离纯化后经NaOH水解生成吉西他滨-~(13)C,~(15)N_2,再进一步降解脱氨得到吉西他滨-~(13)C,~(15)N_2代谢产物。产品经HPLC,LC-MS和~1H NMR表征确定,化学纯度高于98%,~(13)C同位素丰度为99%,~(15)N同位素丰度为98%。结果表明,合成的吉西他滨-~(13)C,~(15)N可用于药物代谢研究。     

Oxidation and Gas Release Behavior of UC,U(C,N) and UN at High Temperature

A study was made of the oxidizing behavior at high temperature (800°–1,800°C) in vacuum of UC, UN and U(C,N) samples containing added oxygen in excess amounts, through observations of gas release, X-ray diffraction analysis, and microphotography.

The oxidation in vacuum of UC and U(C,N) was found to proceed above 1,200°C by stepwise reactions from one temperature interval to the next, the process differing however according to the chemical state of the oxygen present in the samples. In the temperature range below 1,200° C, the UC and U(C,N) samples reacted violently with the free oxygen present in dissolved state, to form UO₂. Between 1,200° and 1,400° C the UO₂ thus produced reacted with the UC or U(C,N), forming solid solutions of U(C,O) and U(C,N,O) respectively: Above 1,600°C, these solid solutions gradually decomposed back into UC and U(C,N), and U. In all stages of oxidation, large amounts of CO—and N₂ in the case of U(C,N)—evolved from the samples as reaction products. In the case of UN, no reaction was observed below 1,200°C, and only oxidized above that temperature to form UO₂ and N₂ by the action of the dissolved oxygen present.

These results indicate that in the case of UC and U(C,N), the quantity of gases evolving from the oxidation is dictated by the total amount of oxygen contained in the samples, while that from UN is dependent on the amount of molecular oxygen alone.     

Extraction of cerium(III) with N,N′-dimethyl-N,N′-dioctyl-diglycolamide in [Bmim][PF6] compared in 40% octanol/kerosene

The extraction of Ce(III) nitrate has been investigated by using N, N′-dimethyl-N, N′-dioctyl-diglycolamide (DMDODGA = L) as extractant with 1-Butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF₆]) as diluent in comparison with 40% octanol/kerosene. DMDODGA in two different diluents shows good extraction ability for Ce(III), but the trends are quite different depending on the concentrations of the ligand in solvent phase and nitric acid in aqueous phase. The slope analysis method is used to obtain the stoichiometric ratio of the extracted complexes. 1:3 complex of Ce(III) to DMDODGA may be formed in both systems, while 1:2 complex may be also formed in DMDODGA-40% octanol/kerosene system. The extraction of Ce(III) is by the cation exchange mechanism in DMDODGA-[Bmim][PF₆] system. Unlike the expected positively charged 1:3 complex of Ce(III) formed in the DMDODGA-40% octanol/kerosene system, the 1:2 complex is assumed to be a neutral complex with two DMDODGA molecules bonding to Ce(III). In addition, the stronger interaction between the C = O groups of L and Ce(III) in the DMDODGA-[Bmim][PF₆] system than in the DMDODGA-40% octanol/kerosene system is confirmed by IR spectroscopy.     

Lattice parameter variation of PuC,PuN, and Pu(C,N) between 50 and 300 K

The lattice parameters of PuC, PuN, and Pu(C, N) were measured between 50 and 300 K (PuC), or 50 and 345 K (PuN and Pu(C, N), resp. No phase transformations are observed in these temperature ranges. The expansion coefficients decrease with decreasing temperature. Below 273 K, PuC shows the same variation of the expansion coefficient as PuO₂, but PuN and Pu(C, N) have higher expansion coefficients than PuC and PuO₂. Below 170 K, the measured lattice contraction of PuC and PuN is lower than the sample contraction determined formerly with strain gauges. A ‘jump’ in the expansion curve of PuC at 80–100 K could not be confirmed.     

Air contamination effects on the compatibility of liquid lithium with molybdenum; TZM,niobium, stainless steels,nickel and hastelloy N in stainless-steel vessels at 600°c

The effects of nonmetallic impurities on the compatibility of liquid lithium with molybdenum, TZM, niobium, type 304 and type 316 stainless steels, nickel and Hastelloy N were investigated. Three compatibility tests (test I, test II and test III), classified by the grade of air contamination of the lithium, were conducted at 600°C for about 1000 h in stainless-steel vessels. In each test the above-mentioned specimens were immersed together in the lithium. In test I weight gain was observed for all the specimens except nickel and Hastelloy N. However, in test II and test III, weight loss was observed for all the specimens. MoNi₃ was produced on the surface of the molybdenum and TZM specimens as a result of the reaction between molybdenum and nickel dissolved in the liquid lithium. NbN_0.9O_0.1 was observed on the surface of niobium specimens in test I and test II, and Nb₂N in test II and test III. The surface of the stainless-steel specimens in test II and test III was depleted with nickel and chromium elements, and deteriorated. The corrosion rates of the test specimens in test III were about 2, 5, 26 and 22 μm/yr for molybdenum or TZM, niobium, type 304 stainless steel and type 316, respectively. Nickel and Hastelloy N were severely attacked by liquid lithium at 600°C. These results were obtained for liquid lithium with a high nickel concentration.