Search

In the 250 Wt RTPV (radioisotope thermophoto-voltaic) system, the heat source operates at a temperature above 1 000 ℃, which requires a long term stable thermal insulation devices. In this paper, three types of non-sealed high temperature MLI (multilayer insulator) were prepared by using spike, stainless steel wire mesh and aerogel as separator respectively. Each type was installed and tested in the RTPV prototype separately. The three MLIs are in the same size of 187 mm long, 183 mm wide and 50 mm thick. In MLI with spike separator, 50 metal foil reflectors were pierced several small holes, the spikes from the holes were used as the separator to make the adjacent reflectors in point contact. In MLI with stainless steel wire mesh separator, 50 stainless steel wire meshes were spot weld on each of the metal foil reflectors as the separator to make the adjacent reflectors in line contact. In MLI with aerogel separator, 18 polished metal plates were used as the reflectors, and slender strip aerogels in size of 50 mm×10 mm×2 mm were installed on four corners between adjacent reflectors as the separator. The main configuration of RTPV prototype tested in this paper was as follow. 1) An electric heating source with the size of 99 mm×95 mm×55 mm was used to simulate the radioisotope heat source. The heat source was supported in RTPV center by seven ceramic nails and coated with tungsten alloy radiation emitter. 2) Four optical filters were placed 34 mm away from the heat source and supported by four inner brackets. 3) Photovoltaic cells were installed on the side walls inside the housing with a distance of 14 mm from the optical filter. 4) Two high temperature MLIs were installed on the upper and lower end covers inside the housing. 5) Cold plates were used on the side walls outside the housing. Vacuum thermal performances of RTPV with different MLIs were carried out on a test platform. Based on the test results, some conclusions come out as follows. 1) The aerogel separator has the best performance in controllability of the assembly separating effect, which leads to the best thermal insulation performance consistency between different batches. 2) When the assembly separating effect is well controlled, the high temperature MLI with spike separator has a better insulation performance than stainless steel wire mesh separator. 3) The optical cavity inside the RTPV prototype is consisted of high-temperature MLI and the optical filters. A better closure of the optical cavity significantly contributes to the improvement of the heat utilization, and accesses to a higher heat source temperature. The optical cavity has the best closure performance when using the high temperature MLI with aerogel separator. While the RTPV prototype with aerogel separator input power is 250 Wt, the heat source temperature reaches 1 038 ℃.

Manganese dioxide (MnO2), as a cathode material for multivalent ion (such as Mg2+ and Al3+) storage, is investigated due to its high initial capacity. However, during multivalent ion insertion/extraction, the crystal structure of MnO2 partially collapses, leading to fast capacity decay in few charge/discharge cycles. Here, through pre-intercalating potassium-ion (K+) into δ-MnO2, we synthesize a potassium ion pre-intercalated MnO2, K0.21MnO2·0.31H2O (KMO), as a reliable cathode material for multivalent ion batteries. The as-prepared KMO exhibits a high reversible capacity of 185 mAh/g at 1 A/g, with considerable rate performance and improved cycling stability in 1 mol/L MgSO4 electrolyte. In addition, we observe that aluminum-ion (Al3+) can also insert into a KMO cathode. This work provides a valid method for modification of manganese-based oxides for aqueous multivalent ion batteries. [ABSTRACT FROM AUTHOR]

Background: Hereditary tyrosinemia type 1 (HT1) is a rare inherited metabolic disease characterized by severe liver and renal dysfunction. Early identification in affected children is critical for improved treatment options and prognosis. Methods: In this study, we identified novel compound heterozygous mutations (NM_000137: c.657delC (p.K220Rfs*12) and c.607G>A (p.A203T)) in the fumarylacetoacetate hydrolase (FAH) gene in a family. We also characterized the clinical phenotype of the proband and verified the pathogenic effects of the mutations. Furthermore, we explored the pathogenic mechanism of renal injury through renal biopsy pathology and cell‐based in vitro assays. Our study aims to verify the association between novel fumarylacetoacetate hydrolase (FAH) variants and HT1, confirm the pathogenic effects of the mutations and explore the pathogenic mechanism of renal injury. Results: We showed these FAH mutations were inherited in an autosomal recessive manner and resulted in abnormal FAH protein expression and dysfunction, leading to fumarylacetoacetate (FAA) accumulation. The proband also showed apparent renal injury, including glomerular filtration barrier dysfunction and abnormal tubular protein reabsorption. Conclusions: These observations may provide deeper insights on disease pathogenesis and identify potential therapeutic approaches for HT1 from a genetic perspective. Similarly, we hope to provide valuable information for genetic counseling and prenatal diagnostics. [ABSTRACT FROM AUTHOR]