MOSSBAUER SPECTROSCOPY OF HIGH T_c YBa_2 (Cu_(3-x)Fe_x )O_y

ＭＯＳＳＢＡＵＥＲＳＰＥＣＴＲＯＳＣＯＰＹＯＦＨＩＧＨＴ＿ｃＹＢａ＿２（Ｃｕ＿（３－ｘ）Ｆｅ＿ｘ）Ｏ＿ｙ￥ＬｉＳｈｉ（李士）ａｎｄＬｉＹｉｎｈｕａ（李印华）（ＩｎｓｔｉｔｕｔｅｏｆＨｉｇｈＥｎｅｒｇｙＰｈｙｓｉｃｓ，Ｂｅｉｊｉｎｇ１０００８０，Ｃｈｉ...     

国产Inconel合金管的性能及应用研究

介绍了国产Ｉｎｃｏｎｅｌ合金管的力学性能、物理性能、各种条件下抗腐蚀性能，以及弯管和胀管试验研究。在腐蚀试验过程中，将国产Ｉｎｃｏｎｅｌ合金管与国外同类材料进行了对比。对比试验结果表明，国产Ｉｎｃｏｎｅｌ合金管在高温浓氯离子溶液和高浓碱溶液中的抗应力腐蚀破裂的能力均优于Ｉｎｃｏｎｅｌ６００和Ｉｎｃｏｌｏｙ８００合金管。     

RESIDUAL GAS IONIZATION BEAM PROFILE MONITOR ON 40MeV H~－ BEAM TRANSPORT LINE

ＲＥＳＩＤＵＡＬＧＡＳＩＯＮＩＺＡＴＩＯＮＢＥＡＭＰＲＯＦＩＬＥＭＯＮＩＴＯＲＯＮ４０ＭｅＶＨ~－ＢＥＡＭＴＲＡＮＳＰＯＲＴＬＩＮＥＸｕＷｅｉｐｅｎｇ（徐伟鹏）（ＩｎｓｔｉｔｕｔｅｏｆＮｕｃｌｅａｒＲｅｓｅａｒｃｈ，ｔｈｅＣｈｉｎｅｓｅＡｃａｄｅｍｙ...     

碘（I~－）在水泥、氢氧化铁和岩盐中吸附行为的研究

采用放射化学法测定了ＡｇＩ在浓盐溶液中的溶解度。用间歇平衡实验研究了浓盐溶液中碘（Ｉ￣－）在水泥、氢氧化铁和天然岩盐中的吸附行为。研究结果表明，在以上三种吸附体系中，Ｉ￣－浓度为１０￣（－７）－１０￣（－４）ｍｏｌ／ｌ时，Ｉ￣－的吸附比（Ｒ＿ｄ）与吸附剂种类有关，与溶液中Ｉ￣－的平衡浓度（ｃ＿（ｅｑ））无关。Ｉ￣－在吸附剂上的浓度（ｃ＿ｓ）与其在溶液中的平衡浓度（ｃ＿（ｅｑ））的关系符合Ｆｒｅｕｎｄｌｉｃｈ方程。     

锝的包合型螯合物研究Ⅰ．三种新的BATO配合物的合成与表征

采用模板反应，以α－二酮肟、取代硼酸、和ＳｎＣｌ＿２为原料，在乙醇－稀盐酸溶液中制得三种锝的包合型螯合物。测定了各化合物的红外光谱及紫外－可见光谱，与已知结构的另一种ＢＡＴＯ配合物￣（９９）ＴｃＣｌ（ＤＭＧ）＿３ＢＣ＿６Ｈ＿４ＣＨ＿３的红外和紫外光谱的谱图相似。     

A COMPLEX-TYPE FOCUSSED MAGNETRON FOR SPUTTERING

ＡＣＯＭＰＬＥＸ－ＴＹＰＥＦＯＣＵＳＳＥＤＭＡＧＮＥＴＲＯＮＦＯＲＳＰＵＴＴＥＲＩＮＧ￥ＺｈｅｎｇＳｉｘｉａｏ（郑思孝）（ＩｎｓｔｉｔｕｔｅｏｆＮｕｃｌｅａｒＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙ,ＳｉｃｈｕａｎＵｎｉｖｅｒｓｉｔｙ,Ｃｈｅｎｇｄｕ...     

THDD－90型中子电离室的标定与考验

文章描述在ＨＷＲＲ上进行的ＴＨＤＤ－９０型中子电离室的中子、γ射线灵敏度刻度，坪特性测量及随堆热考验。结果表明，该电离室的中子灵敏度Ｓ＿ｎ＝２．５×１０￣（－１４）Ａ·ｃｍ￣（－２）·ｓ￣（－１），γ射线灵敏度Ｓ＿ｒ＝０．９４×１０￣（－１１）Ａ·（ｈ·Ｒ￣（－１））。经过１３个月的随堆热考验后，其基本性能保持不变。     

A PHOTOEMISSIVE MONOENERGETIC ELECTRON SOURCE FOR CALIBRATING THE BETA－MAGNETIC SPECTROMETER

ＡＰＨＯＴＯＥＭＩＳＳＩＶＥＭＯＮＯＥＮＥＲＧＥＴＩＣＥＬＥＣＴＲＯＮＳＯＵＲＣＥＦＯＲＣＡＬＩＢＲＡＴＩＮＧＴＨＥＢＥＴＡ－ＭＡＧＮＥＴＩＣＳＰＥＣＴＲＯＭＥＴＥＲ￥ＣｈｅｎＺｈｉｃａｉ（陈志才）；ＳｕｎＨａｎｃｈｅｎｇ（孙汉城）ａｎｄＭａｏＹａｊ...     

~（99）Tc~m－HMPAO构效差异的研究──GSH水溶液中~（99）Tc￣

从化学动力学角度对ｄｌ－型和ｍｅｓｏ－型￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ构效差异的原因进行了研究。通过测定￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ两种异构体在ＧＳＨ和Ｌ－半胱氨酸水溶液中的解离反应的一级速率常数，比较了Ｌ－半胱氨酸和ＧＳＨ对￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ作用，解释了ｄｌ－型和ｍｅｓｏ－型￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ药效的差异，探讨了￣（９９）Ｔｃ￣ｍ－ｄｌ－ＨＭＰＡＯ在人脑中的贮留机理。     

心肌显像剂~（68）Ga（BAT－TECH）的一些基本常数测定

研究了心肌显像剂￣（６８）Ｇａ（ＢＡＴ－ＴＥＣＨ）的动力学性质，测定了它的热力学常数。实验结果表明，ＢＡＴ－ＴＥＣＨ与柠檬酸镓的配体交换反应为二级反应，反应速率常数ｋ为０．５０ｌ／ｍｏｌ·ｓ，反应活化能Ｅ＿ａ＝５６．６ｋＪ／ｍｏｌ；￣（６８）Ｇａ（ＢＡＴ－ＴＥＣＨ）的稳定常数ｌｇβ＝１４．９，配体ＢＡＴ－ＴＥＣＨ的四级氢解离常数ｐＫ＿１＝４．６２，ｐＫ＿２＝７．６８，ｐＫ＿３＝８．６８，ｐＫ＿４＝１１．２。     

Influence of long-term sodium exposure on the composition and microstructure of austenitic alloys

Austenitic alloys (Types 304, 316, 321, 347 stainless steel and Incoloy-800) were exposed to flowing sodium in out-of-pile test loops at 704 °C (1300 °F) and 621 °C (1150 °F) for varying times up to 15726 h. Changes in chemical composition and microstructure increased with increasing exposure time. Major alloying elements (Cr, Ni, Mn) were depleted from surface layers up to 130 μm thick. Unstabilized alloys (Types 304 and 316) lost carbon during exposure while stabilized alloys (Types 321, 347 and I-800) tended to gain carbon. Variations in other minor elements with exposure were determined. Changes in microstructure reflected the compositional changes in all the alloys. Specimens were examined by optical, transmission electron and scanning electron microscopy. A ferrite layer formed at the sodium exposed surface of all alloys except Incoloy-800. Sigma phase precipitation increased with exposure time. In the stabilized alloys cavities formed up to 120 μm below the sodium-exposed surface. The subsurface cavities appeared to be connected to surface pits via intergranular channels and were related to a decrease in density observed in the specimens.     

Behaviour of the steam generator tubing in water with different pH values

Steam generators are crucial components of pressurized water reactors. The failure of the steam generator as a result of tube degradation by corrosion has been a major cause of Pressurized Heavy Water Reactor (PHWR) plant unavailability. Steam generator problems have caused major economic losses in terms of lost electricity production through forced unit outages and, in cases of extreme damage, as additional direct cost for large-scale repair or replacement of steam generators.The excellent performance to date of CANDU steam generators can be attributed, in part, to their design and performance characteristics, which typically involve higher recirculation ratios and lower heat fluxes and temperatures. However, the steam generator tubes are susceptible to failure by a variety of mechanisms, the vast majority of which are related to corrosion.The generalized corrosion is an undesirable process because it is accompanied by deposition of the corrosion products which affect the steam generator performances. It is very important to understand the generalized corrosion mechanism with the purpose of evaluating the quantities of corrosion products which exist in the steam generator after a determined period of operation (IAEA, 1997).The purpose of the experimental research consists in the assessment of corrosion behaviour of the tubes material, Incoloy-800, at normal secondary circuit parameters (temperature—260 °C, pressure—5.1 MPa). The testing environment was the demineralised water without impurities, at different pH values regulated with morpholine and cyclohexylamine (all volatile treatment—AVT).The results are presented like micrographics and graphics representing weight loss of metal due to corrosion, corrosion rate, total corrosion products formed, the adherent corrosion products, released corrosion products, release rate of corrosion products and release rate of the metal.     

Proposed Method of Measuring Thermal Diffusivity of a Small Specimen at Incandescent Temperatures

An evaluation was made of heat transfer tube failure propagation due to sodium-water reaction wastage in a sodium heated steam generator, by comparing an empirically derived wastage equation with leak detector responses.

The experimental data agreed well with the wastage equation even for different values of distance-to-nozzle diameter ratio, though the formula had been based on wastage data obtained for only one given distance. The time taken for failure propagation was estimated for a prototype steam generator, and compared with the responses characteristics of acoustic detectors and level gages. It was found that there exists a range of leak rate between 0.5 and 100g/sec, where the level gage can play a useful role in leak detection. The acoustic detector can be expected to respond more rapidly than the cover gas pressure gage, if noise is kept below ten times the value observed in an experimental facility, SWAT-2.     

氘在Incoloy800H合金材料中的扩散渗透行为

采用气相渗透技术研究了氘在Incoloy800H合金材料中的扩散渗透行为,利用高温气相渗透实验装置和四极质谱仪测定了450～600 ℃温度范围内、氘压110 kPa下氘的渗透实验曲线,计算得到了氘在Incoloy800H合金材料中的渗透率和扩散系数。结果表明,渗透扩散过程为扩散控制,得到的渗透率、扩散系数与温度的关系式均符合Arrhenius关系。     

长白山γ辐射空气吸收剂量率初步调查

结合我国长白山主峰地区典型地形地貌特征,较全面的开展γ辐射空气吸收剂量率水平调查,掌握了第一手的调查数据。调查结果表明长白山主峰的北坡、南坡及西坡海拔高度800m以上各测点地表环境γ辐射剂量率结果随海拔高度变化呈明显的正相关性。本工作的开展也为后续山林地区γ辐射空气吸收剂量率水平测量工作积累经验。     

Sodium/water combustion and the chemistry of wastage at sodium/water leak sites

The ignition and combustion of sodium in water vapour are demonstrated experimentally, and the composition and temperature of the flame region are discussed in terms of thermodynamic and kinetic factors. Steels have been shown to suffer rapid wastage in these flame regions. Corrosion tests to simulate the chemical environment of the flame showed that a greater rate of attack on 2.25C-1 Mo steel occurred with sodium hydroxide in a water vapour atmosphere than with sodium hydroxide alone. Extrapolation of these corrosion rates to the steel temperature in the flame leads to the conclusion that these corrosion processes are the origin of the flame wastage. The tube wastage found during water injection tests in fast reactor heat exchangers is discussed in terms of rapid corrosion by sodium hydroxide and water vapour within the flame region generated at the boundary of the water jet.     

钠冷快堆蒸汽发生器小钠水反应现象数值模拟

蒸汽发生器（SG）是钠冷快堆二回路主冷却系统的关键设备之一,其传热管破损会导致钠水反应事故,产生大量氢气、腐蚀性产物并放出热量,严重影响SG的安全运行。本文用FLUENT对小泄漏钠水反应区的瞬态现象进行数值模拟,计算得到泄漏孔径为0.2 mm时反应区最高温度可达1 564 K,最高温度随泄漏率的增加而升高,但保持在一定范围内,结果均与日本实验结果吻合,并且泄漏率会影响产物NaOH和H₂的扩散与分布。本文采用的数值模拟方法可用于小钠水反应现象分析,可得到不同泄漏率下小钠水反应能达到的最高温度、反应区任意位置的NaOH浓度和H₂浓度,以预测邻管损耗和失效时间,有利于进一步开展小钠水反应事故安全分析。     

环形通道内钠流动起始沸腾壁面过热度实验研究

对环形通道内金属钠起始沸腾壁面过热度进行实验研究。实验段长800 mm,环形通道外径10 mm,内径6 mm。电加热元件最高热流密度为846 kW/m²,进口过冷度为63.1～287.8 ℃,质量流量为7.2～122.0 kg/h,系统压力为0.85～28.79 kPa。实验结果表明,起始沸腾壁面过热度随热流密度和进口过冷度的增加而升高,随质量流量和系统压力的增加而降低。拟合得到了关于起始沸腾壁面过热度的半经验关系式,关系式计算结果与实验数据符合良好。     

Effect of Temperature and Deformation Rate on Fracture Strength of Sintered Uranium Dioxide

The fracture strength of two kinds of UO₂ specimens possessing pores of different maximum sizes (60 and 140 μm) was measured in the range of room temperature ? 1,300°C by means of diametral compression testing. The fracture strength thus obtained proved to be smaller than any of the values reported by previous authors who mainly used bending tests. Finite element analysis showed that the method used in the present study should logically yield results close to the true tensile fracture strength. The descrepancies noted with the results reported from the other studies were attributable to the differences in the methods used for the measurements.

The fracture strength was found to remain almost constant in the relatively low temperature region (R.T.–800°C) beyond which the value increased with temperature (intermediate temperature region of 1,000–1,300°C). Electron-microscopic observations of the fractured surface indicated that the brittle-to-ductile transition temperature (T_c ) was situated between 800 and 1,000°C when the strain was applied slowly. Raising the strain rate proved to affect both fracture strength and T_c . These dependences of temperature and strain rate on the fracture strength are explained from the relation between dislocation velocity and deformation rate. Griffith's theory is cited to describe the relation between the largest pore size and fracture strength.     

Experimental research on the incipient boiling wall superheat of sodium

Incipient boiling wall superheat of sodium flowing in annulus was experimentally investigated. The annulus was 800 mm in length, 6 mm as inside diameter and 10 mm as outside diameter. The heat flux in the experiment was from 128 to 846 kW/m², with inlet subcooling from 63.1 to 287.8 °C, mass flow rate from 7.2 to 122.0 kg/h and system pressure from 0.85 to 28.79 kPa. The experimental results indicated that the incipient boiling wall superheat increased with the increasing heat flux and inlet subcooling. And lower liquid velocity and system pressure could result in a higher incipient boiling wall superheat. Furthermore, a semi-empirical correlation was obtained from the experimental results. It was also found that the predicting results agreed well with the experimental data.