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R.?A.?KuznetsovEmail author I.?G.?Kanterman V.?V.?Eremin V.?G.?Semenov 《Radiochemistry》2018,60(3):323-327
A new type of a promising glassy-crystalline host material was prepared by ultradisperse synthesis in model experiments. The starting product is the nitric acid fraction of fission products (Cs, Sr, Ba), obtained radiochemically from irradiated nuclear fuel of a WWER-1000 reactor (1000-MWel water-cooled water-moderated energy reactor). Equivalent amounts of La(NO3)3, H3PO4, and Fe2O3 are added, and water is removed on heating. After complete removal of moisture, the residue is calcined at 600°С. The phosphated calcinate is dispersed in acetone to obtain slurry and, after removing acetone, converted to the glassy form at 950°С by self-igniting high-temperature synthesis. The whole process of preparing the composite is performed in one container crucible, which is then sealed. The major constituent of the host material is iron (pyro)phosphate glass (~55%); the finely grained crystalline phase, according to X-ray diffraction data, consists mainly of monazite of the composition La2(Sr,Ba)3(PO4)4. The monazite content is about 40%. Monazite forms with the glass via covalent bonding a composite exhibiting high corrosion resistance. The steady-state rate of Cs leaching form the monazite glass is 0.1 μg cm–2 day–1 (90°С, 100 days). 相似文献
23.
The study conducted proved that triombrast (dose dependently) > hexabrics > Ultravist > or = melitrast = omnipac in a concentration interval of 0.03-30.0 mg iodine/ml in vitro and in a dose interval of 0.5-2.0 g iodine/kg in vivo activate the complement system (CS) according to the alternative way in the blood of "sensitive" rats. The degree of CS activation by radiopaque agents (ROA) is significantly determined mathematically by their viscosity and relation of the number of iodine atoms to the number of ions or dissolved particles, and by their hydrophilic (for nonion CS) and osmotic (for ion monomeric CS) properties. 相似文献
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A. G. Eremin L. S. Korobkov A. A. Dubinin A. P. Pyshko K. G. Tkach A. A. Bochvar 《Atomic Energy》1993,74(3):219-224
"Krasnaya Zvezda." Scientific Planning Department Physics Power Institute of New Materials. Translated from Atomnaya Énergiya, Vol. 74, No. 3, pp. 237–243, March, 1993. 相似文献
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The authors studied separate parameters of the reaction of morphological dissociation of clotted blood in 97 patients, 83 of them suffering chronic nonspecific pneumonia and 14--lung cancer. Such RMDCB tests as the amount of the third fraction of blood coagulation (TFCB), the time of TFCB sediment formation and "the prognostic index" are found to be of certain diagnostic value, and along with other laboratory tests and clinical symptoms these allowed a differentiation between chronic nonspecific pneumonia and lung cancer. 相似文献
27.
开展65 nm高速大容量静态随机存取存储器(SRAM)大气中子单粒子效应特性及试验评价技术研究,基于4 300 m高海拔地区大面积器件阵列实时测量试验,突破效应甄别、智能远程测控等关键技术,在153 d的试验时间内共观测到错误43次,其中器件内单粒子翻转39次,多单元翻转(MCU)在单粒子翻转中占比23%,最大的MCU为9位。对高能中子、热中子和封装α粒子的贡献比例进行了分析,并基于多地中子通量数据,推演得到北京地面和10 km高空应用时的单位翻转(SBU)和MCU失效率(FIT)。发现地面处软错误的主要诱因为封装α粒子,随着海拔的增高,大气中子对软错误的贡献比例明显增大;MCU全部由高能中子引起,北京10 km高空处的MCU FIT值明显增大,其占比由地面的8%增大至26%。结合器件版图布局,对MCU产生机理进行了深入分析。最后,提出一种目标导向的存储器软错误加固策略优化方法。 相似文献
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栅氧化层TDDB可靠性评价试验及模型参数提取 总被引:2,自引:2,他引:2
采用恒定电压和恒定电流试验方法对20nm栅氧化层进行了TDDB可靠性评价试验,并完成了1/E模型参数提取,给出了恒定电流应力下描述氧化层TDDB退化的统计模型,较好地解释了试验结果。 相似文献
30.
V. V. Dunaev B. N. Ushakov V. F. Gromov M. V. Eremin 《Journal of Machinery Manufacture and Reliability》2011,40(3):230-236
New designs of bolted joints with bolt countersunk heads having high longevity in comparison with the used ones were proposed. One type of joint has the bolt heads with the reduced surface taper of the bolt head and in a joined part. Two other types have a spherical head surface, which is in contact with a tapered countersink surface. The rise in the fatigue life is achieved owing to the balance of the radial tension along the contact surfaces of the head and the countersink. Designs of a washer from the direction of a nut are proposed. These washers have ring bulges of wedge-shaped cross section that form areas of plastic deformations around a bolt body during the bolt tightening and reduce the concentration of contact stresses close to an edge of the contact surfaces of the bolt and joined parts. Procedures of fatigue tests were developed. Results of tests of the proposed bolted joints supporting their high longevity are presented. Findings of experimental investigations verify the efficiency of the application of proposed types of bolted joints in the designs of aircrafts. 相似文献