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91.
《Journal of the European Ceramic Society》2023,43(5):2151-2163
Li2TiO3 is regarded as a vital tritium breeder candidate due to its favorable properties in Helium-Cooled Pebble Bed. However, the point contact stress breakage for traditional pebble structure can cause the blocking of tritium recovery system, and seriously reduce the safety and tritium self-sufficiency ability of fusion reactor. For addressing above problems, in this paper, complex-shaped Li2TiO3 cubic units were manufactured firstly via lithography-based 3D printing. According to the principle of tritium transport, the cubic unit structures with ordered channels were built and evaluated by finite element analysis. The photocuring parameters were optimized to improve printing accuracy by establishing an overgrowth model. After optimizing the sintering schedule, the Li2TiO3 cubic units with excellent relative density (92.3%TD) and packing factor (80.99%) were yielded, and it also had an outstanding compressive strength (84.4 MPa). The results of thermal cycling test shown that the Li2TiO3 cubic units possessed a prominent thermal cyclic durability. 相似文献
92.
《Ceramics International》2023,49(5):7710-7716
In the present work, we studied structure, surface morphology, and ultrasonic response of thin film Lithium Niobium Oxide (LNO) transducers deposited on Inconel bolts, stainless steel and silicon substrates by radio frequency magnetron sputtering. The deposited transducer material was a mixture of LiNbO3/LiNb3O8 phases, having a well-developed columnar structure. Further, the in-situ high-temperature ultrasonic response was studied in the temperature range of 18–800 °C in ambient air during short-term annealing. It was observed that long-term annealing (at 700 °C for 160 h and 800 °C for 40 h) deteriorated the ultrasonic response, owing to the irreversible change from the initial columnar structure to the porous granular structure. Dielectric and piezoelectric properties of the thin film LNO transducers were also studied. The thin film LNO ultrasonic transducers have potential applications in bolts and screws up to 700 °C. 相似文献
93.
《Ceramics International》2023,49(5):7935-7945
Solid polymer electrolytes (SPEs) have attracted much attention because of their potential in improving energy density and safety. Vanadium doped ceramic matrix Li6.7La3Zr1.7V0.3O12 (LLZVO) was synthesized by high-temperature annealing, and formed a composite electrolyte with polyethylene oxide (PEO). Compared with pure PEO electrolyte membrane, the composite electrolyte membrane exhibited better ionic conductivity (30 °C: 3.2 × 10?5 S cm?1; 80 °C: 3.6 × 10?3 S cm?1). The combination of LLZVO was beneficial to improve the lithium ion transference number (tLi+) of SPE, which was as high as 0.81. The Li/SPE/LiFePO4 battery shows good cycling ability, with a specific capacity of 142 mAh g?1 after a stable cycle of 150 cycles. Meanwhile, the symmetrical lithium battery with composite electrolyte can work continuously for 1200 h without short circuit at the current density of 0.1 mA cm?2 at 50 °C, and the capacity is 0.176 mAh. Vanadium doped ceramic matrix LLZVO as an active ionic conductor, improved the overall performance of solid electrolyte. 相似文献
94.
Dense m-Li2ZrO3 formed by aqueous slip casting technique: Colloidal and rheological characterization
《Ceramics International》2023,49(6):8827-8838
An aqueous colloidal processing method was proposed to prepare m-Li2ZrO3 bodies, with high green density and a homogenous microstructure, employing a pressureless forming technique. For this purpose, the preparation conditions of m-Li2ZrO3 aqueous suspensions were optimized considering colloidal processing variables, such as milling time (0–40 min), dispersant concentration (1–10 wt% of the solids content) and maximum solid loading (41–74 wt%). Particle size distributions and steady-state flow curves of the slips were analyzed, together with phase composition and microstructure of the ceramic bodies. The results show that after planetary ball milling for 30 min, the aqueous suspension with 63.1 wt% of m-Li2ZrO3, and a dispersant content equal to 10 wt% of the solid loading, yielded green bodies with bulk densities close to 66% TD by slip casting. Then, after the heat treatment process at 1100 °C for 12 h, bulk densities close to 88% TD were achieved. It was found that density values and microstructure of the green and sintered products bear a direct relationship to the particle size and the consistency of the slips. 相似文献
95.
《Ceramics International》2023,49(13):21246-21254
A glass with the composition 7.9 Li2O∙2.0 MgO∙1.4 ZnO∙10 Al2O3∙2.7 B2O3∙72.6 SiO2∙0.9 ZrO2∙2.1 TiO2∙0.4 Sb2O3 was thermally treated at temperatures in the range from 650 to 750 °C. During thermal treatment, at first, nearly spherical Zr1-xTixO4 crystals with sizes of 5–20 nm were formed. On these nanocrystals, elongated particles consisting of TiO2 were observed to grow. Subsequently hexagonal β-quartz solid solution was formed at temperatures ≥650 °C. In this β-quartz solid solution, Zn as well as Mg and excess Al were incorporated. At temperatures >690 °C, the formation of tetragonal β-spodumene solid solution was observed. In the microstructure of the formed glass-ceramics, a volume concentration of around 12% spherical aggregates with a diameter of 1.5–2 μm composed of β-spodumene solid solution and areas enriched in Al and Zn occur. These heterogenous structures were formed by the transformation of β-quartz solid solutions to β-spodumene solid solution. At the same time, Zn(Mg) and excess Al were expelled from the aluminosilicate phase and a cubic spinel type phase Zn(Mg)Al2O4 was formed. These aggregates did not contain a glassy phase. In-between these spherical aggregates, i.e. in around 88% of the volume, tiny Zr1-xTixO4 crystals, aluminosilicate crystals with diameters of around 200 nm, and a glass phase shoved away by these growing crystals consisting of oxides of Mg, Zn, Al, Si, and Sb happened to occur. 相似文献
96.
Mehmet Musa Özcan Nurhan Uslu Viktar Lemiasheuski Duygu Akçay Kulluk Sait Gezgin 《Journal of the American Oil Chemists' Society》2023,100(5):403-412
The physico-chemical properties, phytochemicals, mineral contents of tobacco (Nicotiana tabacum L.) seeds grown at Samsun province in Turkey were evaluated. The oil contents of tobacco seeds ranged from 20.6% (control) to 29.0% (microwave-roasted). L*, a* and b* values of tobacco seeds ranged from 32.38 to 35.61; from 6.32 to 6.78; from 13.72 to 14.27, respectively. Total phenolic contents of tobacco seed extract and oils were reported between 31.02 (oven-roasted) and 34.42 mg GAE/100 g (microwave-roasted) to 4.60 (microwave-roasted) and 6.45 mg GAE/100 g (oven-roasted), respectively. Total flavonoid values of raw and roasted tobacco seed extract and oils were determined between 26.62 (oven) and 67.10 mg/100 g (control) to 21.57 (control) and 44.71 mg/100 g (microwave-roasted), respectively. Gallic acid, 3,4-dihydroxybenzoic acid and catechin are the predominant phenolic components of raw and roasted tobacco seed oils. The amounts of oleic and linoleic acid in raw and roasted tobacco seed oils ranged from 10.23% (oven-roasted) to 12.48% (control) and 73.72% (control) to 76.63% (oven-roasted), respectively. The abundant elements found in seeds were K, P, Ca, Mg, S and Fe. The mineral amounts of the roasted seeds were found higher than that of the control. The highest increase was detected in oven roasted tobacco seeds. 相似文献
97.
98.
Jiann-Tsyh Lin Grace Q. Chen Ching T. Hou 《Journal of the American Oil Chemists' Society》2013,90(1):33-38
Castor oil can be used in industry. The molecular species of triacylglycerols containing hydroxy fatty acids (FA) in castor oil have been identified. We report here the identification of twelve diacylglycerols (DAG) containing hydroxy FA in castor oil using positive ion electrospray ionization mass spectrometry of the lithium adducts. They were RR (diricinolein, R is ricinoleate), RL, RS, R‐diOH18:0, R‐diOH18:1, R‐diOH18:2, R‐triOH18:0, R‐triOH18:1, R‐triOH18:2, diOH18:0‐diOH18:1, diOH18:1‐diOH18:1 and diOH18:1‐diOH18:2. The MS2 fragment ions, [M + Li ? FA]+ and [FA + Li]+, from the lithium adducts of DAG containing hydroxy FA (one or two hydroxy FA), were used for the identification. The additional fragment ions from the neutral losses of FA lithium salts [M + Li ? FALi]+ were used for the identification of eleven DAG containing two normal FA in a soybean oil bioconversion product. The MS2 fragment ions from the neutral losses of FA lithium salts [M + Li ? FALi]+ were not detected from the DAG containing hydroxy FA. The DAG containing FA with more hydroxyl groups than the other FA on the same DAG molecule tended to have a prominent fragment ion [FA + Li]+ and an undetectable fragment ion [M + Li ? FA]+ while the FA was the more hydroxylated FA. Also the less hydroxylated FA of a DAG tended to have a prominent fragment ion [M + Li ? FA]+ and an undetectable fragment ion [FA + Li]+ while the FA was the less hydroxylated FA. 相似文献
99.
Petr Ptáček Tomáš Opravil František Šoukal Jaromír Havlica Jiří Másilko Jaromír Wasserbauer 《Ceramics International》2013,39(8):9055-9061
The roentgen-amorphous delaminated and dehydroxylated phase was prepared applying intensive milling procedure and subsequent thermal treatment of talc. Due to the similarity in properties and in thermal behavior of this material with roentgen-amorphous delaminated and dehydroxylated kaolinite phase, i.e. meta-kaolinite, the name meta-talc was suggested for this material. The properties and the behavior during thermal treatment were investigated using thermal analysis, x-ray diffraction analysis, infrared spectroscopy and scanning electron microscopy. The suggested procedure changes the activation energy of dehydroxylation, the behavior during thermal treatment and the phase composition of the product. The kinetics and thermodynamics of the thermal transition were evaluated using Kissinger equation and Eyering law. 相似文献
100.
磷酸铁锂(LiFePO4)作为锂离子电池的正极材料,具有良好的循环性能、热稳定性、较高的容量以及相对低廉的价格,近年来成为电池研究的热点.采用固相法在不同温度下合成LiFePO4,通过X衍射、扫描电镜(SEM)、电池循环性能以及阻抗光谱等对合成产物的组成、结构、形貌和电化学性能进行表征,研究影响产品性能及形貌的主要因素,筛选出合适的合成温度以提高LiFePO4的电化学性能. 相似文献