Study of bronze corrosion is applied in nuclear research field. Bronze relics from different locations under different environments were investigated by mineralographic microscope, electronic probe and X-ray diffraction approach. Neogenic minerals of cuprite, malachite, azurite, cerussite and stannolite were observed in corrosion layers of bronze relics. Corrosion layer of bronze relics consisted of red cuprite sub-layer, green carbonate mineral sub-layer and yellow stannolite sub-layer. The corrosion layer together with the neogenic minerals mentioned above can protect the metal from corrosion. Bronze alloy is suitable for selected material of canister in disposal system of high-level radioactive waste.
In this work, to scale laser power while suppressing NL effects, we designed and fabricated a fiber triple-clad Ytterbium doped fiber with large core diameter by using MCVD combined with all-gas-phase doping method. To modify the PD performance of the fiber, P、Al and F were co-doped in the fiber. An excellent laser performance could be demonstrated for such a fiber with an output power of more than 10 kW and a slope efficiency of 82%. Long-term laser stability at 10 kW-level was carried out in a master oscillator power amplifier (MOPA) laser system for 500 hours with power degradation less than 1%.
By widely investigating and comprehensively analysing a large amount of data,this paper first classified the types of thorium resource in China and discussed the distribution pattern and geological features of each type.And then it made especially introduction on the types of thorium mineralization,thourium minerals and their occurrences of Julong'an U-Th deposit in Xiangshan.The paper finally summarized the distributions pattern of thorium resources in China.
Upconversion (UC) materials have shown many applications in the solar cell industry, biomedical imaging, and LED lighting. For the first time, we report enhanced UC in Er3+/Yb3+-codoped silica glasses induced by the energy transfer between rare earth ions and indium tin oxide nanoparticles (ITO NPs), introduced by an in situ growth approach. The enhancements of the intensities of the emissions of red and green light were all more than 10 fold and in some cases up to 42 fold. This work in our opinion has contributed a novel method and materials for UC enhancement in Er3+/Yb3+-codoped silica glasses.
The concept on geological disposal of high level radioactive waste (H LW) is a multi-barrier sysytem, including waste container, buffer/backfill mate rial and geological formation. Some significant mineralogical problems related t o geological disposal of HLW are shown below: 1.Mineralogical study of montmoril lonite in bentonite is very important in study on buffer/backfill material of HL W repository. Bentonite mainly consisting of Na-montmorillonite and that of Ca -montmorillonite are very different in many properties. What kind of bentonite is better as a buffer/backfill material in HLW repository? 2.Sorption capacity o f - 99 Tc and - 129 I on stibnite, boulaugerite and tiemannite is very good. However, these minerals are rare in the nature. It is necessary for miner alogists to find substitutes of those minerals as additives in buffer/backfill m aterials of HLW repository. 3.Zeolite has a good sorption capac ity for some nuclides. Mineralogists should pay attention to application of zeol ite in geological disposal of nuclear wastes.
Modeling study of corrosion processes of unearthed bronze relics was preformed by EQ3/6,a software package for geochemical modeling of aqueous system.It was revealed that:cuprite,malachite and tenorite are the three main kinds of copper-bearing minerals which would be supersaturated when Cu concentration in the solution is high enough(higher than 0.0016 mol/L,0.0079 mol/L separately) under the study conditions.Copper exists in the solution mainly as the species of CuCO_3(aq),Cu~(2+) and CuOH~+.The corresponding content of CuCO_3(aq) would be decreased following the deposition of the copper-bearing minerals,nevertheless,Cu~(2+) and CuOH~+ would be increased.The species of Cu and the saturation index of the copper-bearing minerals would be greatly affected by the E_h and pH values of the solution.Cuprite is supersaturated in the studied E_h and pH condition(E_h=-0.2 V～0.7 V,pH=5～9.5).Malachite and tenorite are supersaturated under the conditions E_h0.2 V,pH7,while chalcocite is supersaturated under the condition of pH7 and E_h0.2 V.Water-bronze interaction has been revealed that cuprite,malachite,tenorite,cerussite,cassiterite,copper,lead and tin would be formed in a sequence from the early stage to the later stage of the reaction.The simulation calculation also showed the different behavior between Cu and Zn.It has demonstrated that Cu was leached off easily and the corresponding content in outer corrosion layer is lower than the interior layer,but Sn is just contrary.It is believed the corrosion processes of bronze could be divided into two stages:at the first stage,cuprite,malachite and tenorite were formed;cassiterite,cerussite and relic copper,lead and tin were formed in the second stage,which can be found in the outer layer of bronze.The simulation result not only fixed the natural corrosion products,but revealed the corrosion processes also which we could not understand by routine methods.So the geochemical modeling study can be used to simulate the bronze corrosion product and its corrosion processes also.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)