Self-Assembled Nanocomposite Based on SrCo0.7Fe0.2Sc0.1O3-δ as an Efficient Intermediate-to-Low-Temperature SOFC Cathode.

The high performance of intermediate-to-low temperature solid oxide fuel cells (ILT-SOFCs) closely depends on the catalytic activity of the cathode material. However, most high-activity perovskite cathodes are rich in Sr and will arise from Sr segregation during the long-term working, resulting in the decay of activity and stability. Herein, by regulating the calcined way and temperature, a type of self-assembled nanocomposite perovskite cathode is developed, the stoichiometric SrCo0.7Fe0.2Sc0.1O3-δ (SCFSc) powder self-separates into a cubic phase (Pm3̅m, Sc-rich) and a tetragonal phase (P4/mmm, Sc-fewer). Meanwhile, a single cubic phase is prepared with the same formula via calcining the SCFSc pellet. It is found that the nanocomposite cathode shows better oxygen reduction reaction catalytic activity than single cubic SCFSc, caused by lower impedance of oxygen surface exchange and bulk diffusion. Particularly, the nanocomposite SCFSc cathode with the self-assembled heterointerfaces mitigates the Sr segregation and shows a peak power density of 1.17 W cm-2 at 700 °C and excellent stability for ∼101 h at 600 °C. This work provides a strategy for the development of nanocomposite cathodes to mitigate cation segregation and improve catalytic activity and stability.

Selectively "size-excluding" water molecules to enable a highly reversible zinc metal anode.

Significant water-related side reactions hinder the development of highly safe, low-cost aqueous zinc metal batteries (AZMBs) for grid-scale energy storage. Herein, by regulating the length of alkyl chains, we successfully adjust interstitial voids between the polymer chains of a metal soap interface between 1.48 Å (size of a zinc ion) and 4.0 Å (size of a water molecule). Therefore, water molecules are selectively "size-excluded," while smaller zinc ions are permitted to pass through. Consequently, water-related side reactions (including hydrogen evolution and corrosion) could be effectively inhibited. Furthermore, abundant zinc ion tunnels accompanied with zincophilic components facilitate the homogenization of the Zn2+ flux, thus preventing dendrite growth. Therefore, the Zn symmetric cell shows a lifespan of approximately 10 000 cycles at 20 mA cm-2 and 1 mA h cm-2, and the Zn//Na5V12O32 (NVO) full cell delivers much better cycling stability with much higher capacity retention of around 93% after 2000 cycles at 2 A g-1 compared to its bare Zn counterpart (19%). This work provides valuable insights for the utilization of metal soap interfaces and regulation of their channel size between perpendicular alkyl chains to realize precise water shielding, which is not only applicable in ZMBs but also in other aqueous batteries.

Synergistically engineered in-situ self-assembled heterostructure composite nanofiber cathode with superior oxygen reduction reaction catalysis for solid oxide fuel cells.

The engineering and exploration of cathode materials to achieve superior oxygen reduction catalytic activity and resistance to CO2 are crucial for enhancing the performance of solid oxide fuel cells (SOFCs). Herein, a novel heterostructure composite nanofiber cathode comprised of PrBa0.5Sr0.5Co2O5+δ and Ce0.8Pr0.2O1.9 (PBSC-CPO-ES) was prepared for the first time through a synergistic approach involving in-situ self-assembly and electrostatic spinning techniques. PBSC-CPO-ES exhibits exceptionally high oxygen reduction catalytic activity and CO2 resistance, which is attributed to its unique nanofiber microstructure and abundant presence of heterointerfaces, significantly accelerating the charge transfer process, surface exchange and bulk diffusion of oxygen. The introduction of CPO not only effectively reduces the thermal expansion of PBSC but also changes the characteristics of oxygen ion transport anisotropy in layered perovskite materials, forming three-dimensional oxygen ion transport pathways. At 750 °C, the single cell employing the PBSC-CPO-ES heterostructure nanofiber attains an impressive peak power density of 1363 mW cm-2. This represents a notable 60.7 % improvement in comparison to the single-phase PBSC powder. Moreover, PBSC-CPO-ES exhibits excellent CO2 tolerance and performance recovery after CO2 exposure. This work provides new perspectives to the design and advancement of future high-performance and high-stability SOFC cathode materials.

Rare malignant primary spinal intradural extramedullary mesenchymal chondrosarcoma: a case report and literature review.

Background: Mesenchymal chondrosarcoma (MCS) is a rare malignant chondrosarcoma with a high propensity for recurrence and distant metastasis. MCS usually arises from bone tissue, and rarely occurs outside the bone. MCS in the subdural and extramedullary regions of the spinal cord is especially rare. In this article, we report a case of spinal intradural extramedullary MCS with herpes virus infection, which is the first such case reported in East China. Case Description: A 13-year-old male complained of intermittent low-grade fever, sweating, progressive constipation with weakness of both lower extremities and bilateral hypoesthesia after a 5-month history of herpes virus infection. Spinal magnetic resonance imaging (MRI) revealed a subdural-extramedullary solid nodular mass with isointensity on T1-weighted imaging and hyperintensity on T2-weighted imaging that was located behind the superior margin of the T5 vertebral body. The patient was initially diagnosed with thoracic meningioma and underwent spinal cord tumour resection followed by adjuvant chemotherapy. Histopathological examination revealed that the tumour was mainly composed of round or oval cells and mesenchymal chondroid matrix, and gene analysis showed the fusion of HEY1 exon 4 to NCOA2 exon 13. Both test results were consistent with the diagnosis of primary intraspinal MCS. At the 1-year follow-up, the patient received adjuvant chemotherapy, and the reexamination images revealed no evidence of tumour in situ tumour recurrence or distant metastasis. Conclusions: As more research has been done on MCS, it has been found that the disease is more likely to occur in adolescents, but is often overlooked due to its lack of imaging characterization. Therefore, the misdiagnosis rate can be reduced only by closely considering clinical manifestations with pathology and imaging findings. Although MCS is a highly malignant tumour, early primary spinal intradural extramedullary MCS can cause neurological symptoms, early detection and treatment can achieve basic total surgical resection. Postoperative adjuvant chemoradiotherapy can further reduce recurrence.

Expression and clinical significance of organic cation transporter family in glioblastoma multiforme.

BACKGROUND: Solute carrier (SLC) 22 A1, A2, and A3 are polyspecific transporters transporting organic cations like histamine, serotonin, norepinephrine, dopamine, MPP + , and toxins. The expression of SLC22A1-A3 in cancer is seldom investigated, and the function of SLC22A1-A3 in glioblastoma multiforme (GBM) is never elucidated. MATERIALS: In our study, we detected the expression of SLC22A1-A3 in 11 fresh GBMs and tumor-adjacent brain tissues with qPCR, and in 129 paraffin-embedded GBMs with immunohistochemistry (IHC). With chi-square test, we investigated the correlation between expression of SLC22A1-A3 and the clinicopathological factors including patients' age, sex, tumor size, and KPS score. With Kaplan-Meier method and Cox-regression model, we estimated the prognostic significance of SLC22A1-A3 in GBM. RESULTS: SLC22A3 was significantly downregulated in GBMs compared with the tumor-adjacent normal tissues. With univariate survival analyses, we showed that SLC22A3, instead of SLC22A1 and A2, was an independent biomarker predicting favorable prognosis. With multivariate analyses, SLC22A3 was identified as an independent prognostic biomarker indicating the favorable outcome of GBM. CONCLUSIONS: SLC22A3 is an independent favorable prognostic biomarker of GBM. Patients with low SLC22A3 may be more high-risk and should receive more intensive post-operational supervision and treatments.

Synergistically Promoting Coking Resistance of a La0.4Sr0.4Ti0.85Ni0.15O3-δ Anode by Ru-Doping-Induced Active Twin Defects and Highly Dispersed Ni Nanoparticles.

The development of anodes with highly efficient electrochemical catalysis and good durability is crucial for solid oxide fuel cells (SOFCs). This paper reports a superior Ru-doped La0.4Sr0.4Ti0.85Ni0.15O3-δ (L0.4STN) anode material with excellent catalytic activity and good stability. The doping of Ru can inhibit the agglomeration of in situ-exsolved Ni nanoparticles on the surface and induce the formation of abundant multiple-twinned defects in the perovskite matrix, which significantly increase the concentration of oxygen vacancies. The reduced L0.4STRN (R-L0.4STRN) anode shows an area-specific resistance (ASR) of 0.067 Ω cm2 at 800 °C, which is only about one-third of that of stochiometric R-L0.6STN (0.212 Ω cm2). A single cell with the R-L0.4STRN anode shows excellent stability (∼50 h at 650 °C) in both H2 and CH4. Furthermore, R-L0.4STRN exhibits outstanding resistance to carbon deposition, which can be attributed to the synergistic effect of highly dispersed Ni nanoparticles and active twinned defects induced by Ru doping.

Long non-coding RNA TUG1/microRNA-187-3p/TESC axis modulates progression of pituitary adenoma via regulating the NF-κB signaling pathway.

The molecule mechanisms of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in human diseases have been broadly studied recently, therefore, our research aimed to assess the effect of lncRNA taurine upregulated gene 1 (TUG1)/miR-187-3p/tescalcin (TESC) axis in pituitary adenoma (PA) by regulating the nuclear factor-kappa B (NF-κB) signaling pathway. We observed that TUG1 was upregulated in PA tissues and was associated with invasion, knosp grade and tumor size. TUG1 particularly bound to miR-187-3p. TUG1 knockdown inhibited cell proliferation, invasion, migration, and epithelial-mesenchymal transition, promoted apoptosis, and regulated the expression of NF-κB p65 and inhibitor of κB (IκB)-α in PA cells lines in vitro, and also inhibited tumor growth in vivo, and these effects were reversed by miR-187-3p reduction. Similarly, miR-187-3p elevation inhibited PA cell malignant behaviors and modulated the expression of NF-κB p65 and IκB-α in PA cells, and reduced in vivo tumor growth as well. TUG1 inhibition downregulated TESC, which was targeted by miR-187-3p. In conclusion, this study suggests that TUG1 sponges miR-187-3p to affect PA development by elevating TESC and regulating the NF-κB signaling pathway.

Effectively Promoting Activity and Stability of a MnCo2O4-Based Cathode by In Situ Constructed Heterointerfaces for Solid Oxide Fuel Cells.

The development of multiphase composite electrocatalysts plays a key role in achieving the efficient and durable operation of intermediate-temperature solid oxide fuel cells (IT-SOFCs). Herein, a self-assembled nanocomposite is developed as the oxygen reduction reaction (ORR) catalyst for IT-SOFCs through a coprecipitation method. The nanocomposite is composed of a doped (Mn0.6Mg0.4)0.8Sc0.2Co2O4 (MMSCO) spinel oxide (84 wt %), an orthorhombic perovskite phase (11.3 wt %, the spontaneous combination of PrO2 additives and spinel), and a minor Sc2O3 phase (4.7 wt %). The surface of the (Mn0.6Mg0.4)0.8Sc0.2Co2O4 phase is activated by the self-assembled nanocoating with many heterogeneous interfaces. Thence, the ORR kinetics is obviously accelerated and an area-specific resistance (ASR) of ∼0.11 Ω cm2 is obtained at 750 °C. Moreover, a single cell with the cathode shows a peak power density (PPD) of 1144.1 mW cm-2 at 750 °C, much higher than that of the cell with the MnCo2O4 cathode (456.2 mW cm-2). An enhanced stability of ∼120 h (0.8 A cm-2, 750 °C) is also achieved, related to the reduced thermal expansion coefficient (13.9 × 10-6 K-1). The improvement in ORR kinetics and stability can be attributed to the refinement of grains, the formation of heterointerfaces, and the enhancement of mechanical compatibility.

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co-Fe Nanoparticles for Solid Oxide Fuel Cells.

The broad and large-scale application of solid oxide fuel cells (SOFCs) technology hinges significantly on the development of highly active and robust electrode materials. Here, Ni-free anode materials decorated with metal nanoparticles are synthesized by in situ reduction of Fe-doping Sr2CoMo1-xFexO6-δ (x = 0, 0.05, 0.1) double perovskite oxides under a reducing condition at 850 °C. The exsolved nanoparticles from the Sr2CoMo0.95Fe0.05O6-δ (SCMF0.05) lattice are Co-Fe alloys with rich multiple-twinned defects, significantly enhancing the catalytic activity of the SCMF0.05 anode toward the oxidation of H2 and CH4. The electrolyte-supported single cell with the reuduced SCMF0.05 anode reaches peak power densities as high as 992.9 and 652.3 mW cm-2 in H2 and CH4 at 850 °C, respectively, while maintaining superior stability (∼50 h at 700 °C). The reduced SCMF0.05 anode also demonstrates excellent coking resistance in CH4, which can be attributed to the increased oxygen vacancies due to Fe doping and the effective catalysis of multiple-twinned Co-Fe alloy nanoparticles for reforming of CH4 to H2 and CO. The findings in this work may provide a new insight for the design of highly active and durable anode catalysts in SOFCs.

La0.6Sr0.4Co0.2Fe0.8O3-δ/CeO2 Heterostructured Composite Nanofibers as a Highly Active and Robust Cathode Catalyst for Solid Oxide Fuel Cells.

The lack of highly active and robust catalysts for the oxygen reduction reaction (ORR) at the intermediate temperatures significantly hinders the commercialization of solid oxide fuel cells (SOFCs). Here, we report a novel heterostructured composite nanofiber cathode composed of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) and CeO2 nanoparticles, synthesized by using a coaxial electrospinning technique, which exhibits remarkably enhanced ORR activity and durability as compared to single LSCF powder and nanofibers. This cathode achieves a polarization resistance of 0.031 Ω cm2 at 700 °C, approximately 1/5 of that for the LSCF powder cathode (0.158 Ω cm2). Such enhancement can be attributed to the continuous paths provided by nanofibers for efficient mass/charge transport and the interdiffusion of La and Ce at the heterointerface which leads to more oxygen vacancy formation. Furthermore, the anode-supported cell with the LSCF/CeO2 composite cathode shows excellent stability (0.4 V for ∼200 h at 600 °C) because of suppression of Sr segregation in LSCF by introducing CeO2 and the structure of heterogeneous nanofibers. These results indicate that the microstructure design of this heterostructured composite nanofiber for LSCF/CeO2 is extremely effective for enhancing ORR activity and stability. This finding may provide a new strategy for the microstructure design of highly active and robust ORR catalysts in SOFCs.