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Introduction: Diabetes mellitus is one of the most important health issues worldwide. The rising incidence of the disease has resulted in a parallel increase of complications such as diabetic foot ulcers (DFU). It is estimated that 25% of patients with diabetes will develop foot ulcers over a lifetime. In Mexico, this lifetime incidence is about 40% to 50%, and 20% of the cases will require amputations. DFU can result in staggering financial burdens for the healthcare system and the patient. Therapies that promote rapid and complete healing and reduce the need for expensive surgical procedures would impact these costs substantially. Methods: Cu/TiO2–SiO2 nanoparticles were synthesized by T. López et al. sol-gel patented method. After synthesis, they were characterized using transmission electron microscopy (TEM) and X-ray diffraction. Then, they were embedded in a polymeric gel matrix. The Cu/TiO2–SiO2 nanogel was used as conservative therapy for a chronic non-healing DFU on a 62-year old female with several comorbidities and chronic complications of diabetes. Wound debridement was performed prior to nanogel administration. The nanogel was applied over the ulcer on alternate days for an initial period of 2 weeks and then continued for 10 months. Results: Significant improvement was observed in the wound healing process since the first applications. The infection was limited and tissue regeneration was enhanced until complete healing of the ulcer. Conclusion: Cu/TiO2–SiO2 nanogel therapy enhanced reepithelialization and healing of the DFU. The successful outcome allowed to avoid the amputation that was proposed for the patient.

Spacecraft hatch needs to be tested for leakage in various environments. Hatch Quick Leak Detector (HQLD) leak testing method is a convenient and effective method for the orbital hatch. Vacuum Chamber leak testing (VCLT) method is a proper integral leakage rate method for the hatch. We performed the testing in the “CMK2000” vacuum vessel. The detection principles and steps are described in detail. Leak testing was performed on all of the hatch seals using helium mass spectrometer leak detectors and special apparatus under the Thermal Vacuum testing. We performed leak testing after finishing operating the hatch in the Thermal Vacuum environment. The relative uncertainty of the total leakage rate value of the hatch is 23.6% (k = 2). The total leakage rate testing was a successful example of complex quantitative leakage rate testing in a middle vacuum chamber.

BaO–CaO–Al 2 O 3 –B 2 O 3 –SiO 2 (BCAS) glass–ceramics can be used as sealant for large size planar anode-supported solid oxide fuel cells (SOFCs). BCAS glass–ceramics after heat treatment for different times were characterized by means of thermal dilatometer, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that the coefficients of thermal expansion (CTE) of BCAS glass–ceramics are 11.4×10 −6 K −1 , 11.3×10 −6 K −1 and 11.2×10 −6 K −1 after heated at 750 °C for 0 h, 50 h, and 100 h, respectively. The CTE of BCAS matches that of YSZ, Ni–YSZ and the interconnection of SOFC. Needle-like barium silicate, barium calcium silicate and hexacelsian are crystallized in the BCAS glass after heat-treatment for above 50 h at 750 °C. The glass–ceramics green tape prepared by aqueous tape casting can be directly applied in sealing the cell of SOFCs with 10 cm×10 cm. The open circuit voltage (OCV) of the cell keeps 1.19 V after running for 280 h at 750 °C and thermal cycling 10 times from 750 °C to room temperature. The maximum power density is 0.42 W/cm 2 using pure H 2 as fuel and air as oxidation gas. SEM images show no cracks or pores exist in the interface of BCAS glass–ceramics and the cell.

A series of nano-crystalline ceria-based solid solution electrolyte, Ce0.8La0.2−x MgxO2−δ (x = 0.0, 0.05, 0.10, 0.15, and 0.2), were synthesized via the polyvinyl alcohol (PVA) assisted combustion method, and then characterized to the crystalline structure, powder morphology, sintering micro-structure, and electrical properties. Present study showed that Ce0.8La0.2−x Mg x O2−δ was exceedingly stable as a cubic phase in all temperature range and exhibited fine crystals ranging from 15 to 20 nm. After sintering at 1,400 °C, the as-prepared pellets exhibited a dense micro-structure with 96 % of theoretical density. The electrical conductivity was studied using AC impedance spectroscopy and it was observed that the composition Ce0.8La0.1 Mg0.1O2−δ showed higher electrical conductivity of 0.020 S cm−1 at 700 °C. The thermal expansion was measured using dilatometer technique in the temperature range 30–1,000 °C. The average thermal expansion coefficient of Ce0.8La0.1 Mg0.1O2−δ was 12.37 × 10−6 K−1, which was higher than that of the commonly used SOFC electrolyte YSZ (~10.8 × 10−6 K−1).

以水系流延法制备阳极支撑型平板式IT-SOFC的阳极/电解质(Ni-YSZ/YSZ)半电池, 通过浸渍La 2 O 3 颗粒对半电池阳极进行改性, LSM+8YSZ为阴极制备单电池。采用扫描电子显微镜(SEM)观察单电池显微结构; 利用能谱(EDS)测试阳极成分; 单电池以乙醇水蒸气为燃料, 在750℃下利用循环伏安法测试单电池的功率密度, 交流阻抗法测试单电池的阻抗。结果表明: 单电池Ni/YSZ阳极孔洞中浸渍的La 2 O 3 颗粒约90 nm; 浸渍改性的电池比未浸渍的电池具有更稳定的电性能, 随着La 2 O 3 浸渍量越来越多, 电池的电性能和稳定性越来越好, 抗积碳能力越来越强。当浸渍量为2.4wt%时, 以乙醇水蒸气为燃料在750℃下运行7 h后, 电池衰减率仅为0.09%/h。

采用溶胶–凝胶法制得MnCo 2 O 4 纳米粉体, 通过XRD和TEM分析了粉体的物相和形貌; 通过添加适量乙基纤维素和松油醇经研磨制成浆料, 并采用丝网印刷法涂覆于SUS430基片上, 在900℃下95%N 2 +5%H 2 气氛中保温3 h, 再于800℃空气气氛中保温10 h烧结得到涂层。采用SEM对涂层的表面和断面进行了观察, 在750℃空气气氛下测试了SUS430/MnCo 2 O 4 样品的导电性能和抗氧化性能, 最后采用EDS对涂层的断面进行分析。结果表明: MnCo 2 O 4 粉体为单一的立方尖晶石相, 晶粒大小均匀, 粒径约150 nm; MnCo 2 O 4 涂层致密,与基体紧密结合且厚度均匀。SUS430/MnCo 2 O 4 样品在750℃空气气氛下经1000 h氧化后, 氧化增重量仅为0.15 mg/cm 2 , 是SUS430合金氧化增重量的1/6; 面比电阻值为0.026 Ω·cm 2 , 比SUS430合金的面比电阻值低了两个数量级; EDS结果表明: Cr元素主要分布在涂层与合金的界面, 在涂层内部无分布。研究显示, MnCo 2 O 4 涂层能显著降低SUS430合金基体的氧化速率, 有效改善其在高温下的导电性能, 并成功抑制Cr元素的挥发。