DEB消氢剂的吸氢性能

以DEB和Pd/C催化剂为原料,按照一定配比,采用研磨法制备出DEB-Pd/C消氢剂。利用PVT法对DEB-Pd/C消氢剂的吸氢性能进行了研究,同时利用拉曼光谱考察了其消氢前后的性质变化。初步实验结果表明:新制备的消氢剂实际吸氢容量可达理论吸氢容量的87.5%,在达50%理论吸氢容量时仍能将氩气中的氢体积分数控制在10×10-6以下;拉曼光谱测量表明,DEB-Pd/C消氢剂的炔键振动强度随着消氢剂吸氢量的增加而减弱。     

热处理对LaNi4.25Al0.75/SiO2复合材料储氢特性的影响

采用气相二氧化硅法制备了LaNi_4.25Al_0.75/SiO₂复合材料。研究了该复合材料经不同温度（473～1 073 K）热处理后的相组成、形貌及吸放氢p-C-T曲线、吸氢动力学性能和吸放氢循环性能。结果表明,随着热处理温度的升高,LaNi_4.25Al_0.75/SiO₂复合材料吸氢量减少,平台压升高,平台斜率略有增加,而动力学性能并无显著变化。经60次吸放氢循环后,经不同温度热处理后的样品均未出现粉化现象,且与未循环样品储氢性能基本保持一致。     

Ni掺杂对金属V抗毒化性能的影响

采用磁悬浮感应熔炼法制备VNi_0.01合金,完全活化后,在含0.5%CO₂的1.0 MPa毒化气氛中进行吸氘反应。在反应初期VNi_0.01合金与纯V相比,仍保持较快的吸氘速率,随后合金吸氘速率迅速下降直至为零。样品毒化后经加热除气处理,样品室内再次充入1.0 MPa高纯氘气,VNi_0.01合金吸氘速率已恢复至完全活化时的水平,而纯V的吸氘速率则低于初次活化时的吸氘速率。合金经活化后测得其增压性能在300～400 K范围内均优于纯V,因而合金有望用于增压化学床。这些研究结果将为该材料的应用提供直接依据。     

压水堆大修下行工况冷却剂主要辐解产物计算研究

压水堆大修时活化腐蚀产物源项控制是降低集体剂量最有力的手段，冷却剂辐解的影响必须予以考虑。本文基于水辐解反应动力学原理，构建了冷却剂辐解动力学模型，根据该模型计算得到了主要辐解产物H₂O₂、O₂和H₂在各工况的生成情况，并讨论了微观反应机理。结果表明：(1)在停堆下行过程中，冷却剂温度从310℃逐步下降到60℃，溶解氢浓度逐步降为0，一回路从还原性转为氧化性，H₂O₂和O₂的生成显著上升；(2)温度、B/Li浓度、溶解氢浓度、H₂O₂和O₂初始浓度等多种因素均会影响辐解产物的浓度；(3)H₂O₂和O₂是相互促进生成的关系，H₂可以显著抑制H₂O₂和O₂的生成，但高浓度的H₂O₂     

贮氚非晶态锆钒合金膜中的氦释放行为

用热解吸和静态贮存方法对贮氚非晶态ZrV₂合金膜中³He的释放行为进行了系统分析。结果显示：³He原子存在597.3、725.8和1 146.6 K等3个解吸峰,其中第3解吸峰的解吸量最大,是由非晶态基体中的³He释放形成;在长达2 423 d的静态贮存期间,非晶膜中³He原子的释放系数始终在10^-5量级范围内波动并呈线性上升趋势,但仍未加速释放;贮存温度变化会引起释放系数剧烈波动;与贮氚晶态ZrV₂合金膜相比,非晶膜的固氦能力显著增强。上述结果初步证实了非晶合金具有良好的固氦性能,这有助于人们从全新视角认识材料中的氦行为。     

氦中痕量杂质气体气相色谱检测分析方法研究

为实现聚变堆氘氚燃料工艺气中痕量杂质气体组分的快速检测分析,需建立特殊的高精度在线气相色谱检测分析方法。以高纯氦作为载气,在不同的色谱柱温度和载气流速控制下,通过分子筛毛细管柱和PLOT-Q柱进行分离,采用放电氦离子化检测器（DID）进行检测,对氦中含量为1、10以及100 ppm的杂质标准气体进行检测分析。结果表明：在柱温为40 ℃、流速为15～20 mL/min实验条件下,分子筛柱在160 s内能够实现H₂、O₂、N₂、CH₄和CO全部分离,且柱效较高,响应值的重复性较好,H₂和O₂之间的分离度高于1.5,实现了完全分离;在柱温为40 ℃、流速为20 mL/min时,PLOT-Q柱分离CO₂组分效果最佳。     

氨水溶液在γ场中的稳态辐射分解行为研究

含氨冷却剂被应用于压水堆中,可以清除冷却剂辐射分解产生的O₂、H₂O₂等氧化性产物,从而减轻结构材料腐蚀。本文研究了氨水在γ辐射场中的辐射分解行为,考察氨浓度、辐射吸收剂量和吸收剂量率、气液体积比和不同饱和气体对氨水辐射分解行为的影响,重点关注辐射分解产物H₂O₂和NO₂-的浓度变化。结果表明,随着体系中氨浓度的增加,H₂O₂的浓度受到明显抑制,NO₂-的浓度则呈现出上升趋势;吸收剂量的增加使得H₂O₂浓度明显升高,NO₂-的浓度则在吸收剂量为8 kGy时达到最大(>100μmol/L),而后降低;吸收剂量率的差异(2.78～25 Gy/min)并未导致H₂O₂和NO₂-浓度产生明显变化;氨水中的O₂是NO₂     

CO2+O2地浸采铀饱和树脂酸化技术与应用

介绍了CO₂+O₂地浸采铀和酸法地浸采铀的水冶回收工艺,依据新疆某地浸铀矿山的铀矿水冶工艺现状,提出将CO₂+O₂地浸采铀工艺下饱和树脂纳入酸法地浸水冶回收系统进行处理的酸化工艺。分析了CO₂+O₂浸出工艺下碳酸铀酰型饱和树脂的酸化转化机理,开展了以酸法水冶系统中淋洗剂、转型剂、洗涤合格液为酸化剂的搅拌浸泡试验。结果表明,酸法水冶系统中的洗涤合格液是符合工艺要求的酸化剂,可充分利用洗涤合格液中的剩余酸度对碳酸铀酰型饱和树脂进行转化,并将转化后树脂对铀的吸附容量由74.71 g/L提高至76.73 g/L,实现了与酸法水冶系统再饱和树脂的共同淋洗和转型。     

应用于等离子体排灰气处理的甲烷水汽重整反应的热力学分析

Tokamak装置中的等离子体反应一段时间后,需对产生的排灰气进行净化处理,以回收其中的氘氚。目前拟采用甲烷水汽重整反应将化合态的氘氚转化为单质并回收。本文运用Gibbs自由能最小化方法,对应用于等离子体排灰气处理的水汽重整反应进行热力学分析,考查反应温度、原料比例、反应压力、O₂、CO₂、H₂、CO等因素对反应平衡的影响,确定了适宜的反应条件,即反应温度范围650～700 ℃,压力1×105 Pa,水碳比1.5～2.0。此外,原料气中O₂或CO₂的存在有利于减少积碳的生成量,并获得较高的氢同位素平衡转化率;H₂的存在对重整反应的热力学平衡无明显影响;CO的存在会使积碳量增加,对反应产生不利影响,在进入重整反应器前应将其去除。     

反应堆非能动氢气复合器严重事故下消氢性能研究

非能动氢气复合器（PAR）是核电厂主要的消氢措施。在严重事故下,某些裂变反应产生的特殊杂质(如I₂、CsI、CO等)可能对催化剂产生有害的影响,为保证PAR消氢性能的可靠性,中毒机理研究十分必要。本文根据相关试验研究结果,从铂、钯金属原子分布结构、催化反应性面积两个方面对催化剂中毒效应进行机理分析,研究得出催化剂中金属原子的分布结构、进入PAR的实际毒物浓度等均是影响催化剂中毒效应的关键因素。     

Poisoning and saturation of St 737 getter alloy in the conversion of isotopic waters to isotopic hydrogen

The results of the studies performed to investigate the saturation capacity of St 737 getter alloy (Zr[V_0.5Fe_0.5]₂) in its application for conversion of water to hydrogen and the functional behaviour of the conversion reaction rate with large oxygen concentration in the alloy are reported. The experiment was performed with the getter alloy at a temperature of 400°C. The conversion process was monitored by two independent techniques — (i) by the hydrogen release, using a quadrupole mass spectrometer and (ii) by the quantity of water reduction in liquid phase. It was found that more than 100 mg of water was converted and 13 Pa m³ of hydrogen was released by a gram of alloy. A chemical analysis of the alloy performed after the experiment showed that the oxygen content in the alloy was about 7% by weight. The post-experiment diffraction analysis of the alloy showed that the crystalline structure of the alloy is almost completely destroyed and that the oxides formed are essentially amorphous. A brief discussion of the significance of the results for the application to tritiated water handling in future fusion reactions is also given.     

Hydrogen uptake of DPB getter pellets

The physical and chemical properties of 1,4-diphenylbutadiyne (DPB) blended with carbon-supported Pd (DPB-Pd/C) in the form of pellets during hydrogenation were investigated. A thermogravimetric analyzer (TGA) was employed to measure the kinetics of the hydrogen uptake by the DPB getter pellets. The kinetics obtained were then used to develop a semi-empirical model, based on gas diffusion into solids, to predict the performance of the getter pellets under various conditions. The accuracy of the prediction model was established by comparing the prediction models with independent experimental data on hydrogen pressure buildup in sealed systems containing DPB getter pellets and subjected to known rates of hydrogen input. The volatility of the hydrogenated DPB products and its effects on the hydrogen uptake kinetics were also analyzed.     

高频燃烧-红外法测定氢化锂中的碳量

采用HCS-878F型高频红外碳硫分析仪，探讨了LiH中碳含量测定的可行性，并进行了加热温度、助熔剂种类及用量、取样量等条件实验研究。实验表明：利用样品燃烧过程中功率分时增加的优点，使样品中的氢气缓释，阻止了爆鸣。通过在分析气流气路上加装一氧化碳转化二氧化碳装置，消除了因大量氢气释放对测量结果的影响，实现了轻材料中碳含量的快速测定，提高了测量结果的准确性和精确度。在样品取样量约为30 mg，碳含量为500～3 000 μg/g时，相对标准不确定度优于10%，碳酸锂标准加入到LiH中的碳回收率为91%～108%。     

Evaluation of ZrCo and other getters for tritium handling and storage

Several hydrogen getter materials of potential interest for the handling, transport, and storage of tritium were compared on the basis of properties such as dissociation pressure, storage capacity, P-c isotherms, rate of hydrogen uptake, recoverability of the gettered hydrogen, reactivity with impurities, characteristics of the fusion fuel cycle, pyrophoricity in air and in pure oxygen, aging, etc., employing data from the literature as well as results from experiments carried out during the course of this study.

The evaluation of the examined getter materials allows the conclusion that the ZrCo alloy may replace uranium for interim storage of tritium in technical applications.     

LaNi_(4.25)Al_(0.75)吸氕、氘、氚热力学同位素效应

采用自制的全金属氢化物吸放氢实验装置,恒温等容条件下测定LaNi_(4.25)Al_(0.75)材料吸氕、氘、氚单质气体的压力-组成等温线(P-C-T曲线),并根据Van’t Hoff(范特霍夫)方程得到LaNi_(4.25)Al_(0.75)吸氕、氘、氚形成氢化物相的热力学参数焓变ΔH分别为:-44.5、-45.0、-47.1kJ·mol-1,熵变ΔS分别为:-118.0、-121.8、-127.5J·mol~(-1)·K~(-1)。结果表明:LaNi_(4.25)Al_(0.75)材料吸收氕、氘、氚单质气体,在温度较低时,同位素效应不明显;温度高于100℃时,热力学同位素效应显著。相同温度、吸气容量条件下,吸气平衡压力从低到高依次是氕、氘和氚,其反应焓变和熵变从小到大依次是氚、氘和氕。结果表明,LaNiAl合金吸氢的热力学同位素效应依赖于温度的变化。     

Effects of hydrogen content and temperature on fracture toughness of Zircaloy-4

The influence of hydrogen content and temperature on the fracture toughness of a Zircaloy-4 commercial alloy was studied in this work. Toughness was measured on CT specimens obtained from a rolled material. The analysis was performed in terms of J-integral resistance curves. The specimens were fatigue pre-cracked and hydrogen charged before testing them at different temperatures in the range of 293–473 K. A negative influence of the H content on material toughness was important even at very small concentrations, being partially restored when the test temperature increased. Except for some specimens with high H concentration tested at room temperature, the macroscopic fracture behaviour was ductile. The role of Zr-hydrides and Zr(Fe,Cr)₂ precipitates in the crack growth and the dependence with hydrogen content were analysed by observation of the fracture surfaces and determination of the Zr(Fe,Cr)₂ precipitates density on them.     

Hydrogen dynamics in electrochromic multilayer systems investigated by the N technique

The resonant reaction ¹H(¹⁵N, γ)¹²C was used to determine the depth distribution of hydrogen in two electrochromic multilayer systems. The systems can be bleached and colored by applying an external voltage. To test models explaining this effect by a change of H content (c_H) in electrochromic layers, H profiles of the systems were measured as a function of the applied voltage. For NiO_x, c_H was found to vary as predicted, whereas for WO₃, c_H changes were smaller than expected. Additionally, H uptake into the ITO electrode was observed.     

Effect of Cr2O3 nanosheet insertion on the deuterium permeation behavior of a Cr-Zr-O coating

In this study, a Cr₂O₃ nanosheet (Cr₂O₃ NS) inserted Cr-Zr-O coating was developed as a hydrogen isotope permeation barrier. The Cr₂O₃ NSs, fabricated by rapid heat treatment, were amorphous with a thickness of only several nanometers. These Cr₂O₃ NSs were then incorporated into a Cr-Zr-O multi-metal oxide composite coating via a dip-coating method to form a coating. The effect of the Cr₂O₃ NS concentration on the morphology, microstructure and deuterium permeation resistance of the coating was studied. With the addition of 1.0 g l−1 Cr₂O₃ NSs, compared with the Cr-Zr-O coating without NSs, the permeation reduction factor of the resultant coating was enhanced from 249 °C to 575 °C at 500 °C. The coating, with a thickness of nearly 193 nm, achieved a comparable deuterium resistance that was above two orders of magnitude higher than the steel substrate. The results show that ceramic NSs can serve as effective fillers for enhancing the coating performance when functioning as a hydrogen isotope barrier.     

Organic decomposition in supercritical water by an aid of ruthenium (iv) oxide as a catalyst-exploitation of biomass resources for hydrogen production-

The present paper deals with the production of hydrogen from biomass in supercritical water in the presence of ruthenium(IV) dioxide, RuO₂, as a catalyst. Experiments were carried out to gasify cellulose and lignin, the mixtures of cellulose and lignin for the simulation of biomass, and finally actual biomass such as pulp, waste paper and paper sludge. Each sample was loaded in a reaction vessel under argon atmosphere at 450°C and around 44 MPa for 120 min. The gas produced was quantitatively analyzed by an on-line gas chromatography. It was found that RuO₂ enhanced the decomposition ratios for cellulose and pulp, but not for lignin and lignin containing compounds. Obviously, lignin deactivated the catalytic effect of RuO₂. The hydrogen production ratios in gasses produced were 15.0% from cellulose, 14.1% from pulp, 21.0% from the mixture of cellulose and lignin, 16% from waste paper and 27% from and paper sludge, respectively. We have concluded that the present method would be feasible for the production of hydrogen.