Exploring Cr and molten salt interfacial interactions for molten salt applications.

Molten salts play an important role in various energy-related applications such as high-temperature heat transfer fluids and reaction media. However, the extreme molten salt environment causes the degradation of materials, raising safety and sustainability challenges. A fundamental understanding of material-molten salt interfacial evolution is needed. This work studies the transformation of metallic Cr in molten 50/50 mol% KCl-MgCl2via multi-modal in situ synchrotron X-ray nano-tomography, diffraction and spectroscopy combined with density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Notably, in addition to the dissolution of Cr in the molten salt to form porous structures, a δ-A15 Cr phase was found to gradually form as a result of the metal-salt interaction. This phase change of Cr is associated with a change in the coordination environment of Cr at the interface. DFT and AIMD simulations provide a basis for understanding the enhanced stability of δ-A15 Cr vs. bcc Cr, by revealing their competitive phase thermodynamics at elevated temperatures and probing the interfacial behavior of the molten salt at relevant facets. This study provides critical insights into the morphological and chemical evolution of metal-molten salt interfaces. The combination of multimodal synchrotron analysis and atomic simulation also offers an opportunity to explore a broader range of systems critical to energy applications.

Temperature-Dependent Morphological Evolution during Corrosion of the Ni-20Cr Alloy in Molten Salt Revealed by Multiscale Imaging.

Understanding the mechanisms leading to the degradation of alloys in molten salts at elevated temperatures is significant for developing several key energy generation and storage technologies, including concentrated solar and next-generation nuclear power plants. Specifically, the fundamental mechanisms of different types of corrosion leading to various morphological evolution characteristics for changing reaction conditions between the molten salt and alloy remain unclear. In this work, the three-dimensional (3D) morphological evolution of Ni-20Cr in KCl-MgCl2 is studied at 600 °C by combining in situ synchrotron X-ray and electron microscopy techniques. By further comparing different morphology evolution characteristics in the temperature range of 500-800 °C, the relative rates between diffusion and reaction at the salt-metal interface lead to different morphological evolution pathways, including intergranular corrosion and percolation dealloying. In this work, the temperature-dependent mechanisms of the interactions between metals and molten salts are discussed, providing insights for predicting molten salt corrosion in real-world applications.

The Clinical Significance of Nasal Nitric Oxide Concentrations in Preschool Children with Nasal Inflammatory Disease.

BACKGROUND: Allergic rhinitis is an allergic inflammation of the nasal airways, and chronic rhinosinusitis is an inflammation of the paranasal sinuses. It can be induced by infection, allergy, or autoimmune problems. Diagnosis of these two diseases is made primarily based on clinical symptoms, allergen test, and imaging. The allergen test is invasive and expensive. The imaging test is harmful to children. Measurement of nasal nitric oxide (NNO) was noninvasive, without radiation, and inexpensive. This study was to evaluate the clinical significance of NNO in preschool children with nasal inflammatory diseases. METHODS: A total of 55 cases of allergic rhinitis, including 35 mild cases and 20 moderate to severe cases, and 33 cases of chronic rhinosinusitis, including 18 mild cases and 15 moderate to severe cases were selected as the experimental group. Fifty healthy preschool children were chosen as the control group. The levels of NNO in all children were measured. The differences in the levels of NNO among allergic rhinitis, chronic rhinosinusitis, and the control group were compared. The levels of NNO in the control group were also analyzed. RESULTS: The levels of NNO were significantly higher in preschool children with allergic rhinitis than in the control group, and the differences were significant. However, the levels of NNO in preschool children with chronic rhinosinusitis were lower than in the control group. In the control group, the levels of NNO were not significantly different between genders, and no significant correlation between NNO levels and the children's height was found. CONCLUSION: As a noninvasive method for detecting nasal inflammatory diseases, measuring the levels of NNO had a high clinical significance in preschool children.

[A study of double antigen sandwich colloidal gold immunochromatography rapid detection for Mycobacterium tuberculosis antibody].

OBJECTIVE: To establish a simple, fast and accurate double antigen colloidal gold immunochromatographic technique for detecting Mycobacterium tuberculosis antibody from tuberculosis patients. METHODS: The fusion protein ESAT-6-16-38 was constructed by using gene cloning technique for the 6, 16 and 38 kDa early secreted antigenic target from Mycobacterium tuberculosis. The ESAT-6-16-38 fusion protein was marked to colloidal gold to establish the double antigen colloidal gold immunochromatographic assay. Serum samples from 163 patients with tuberculosis, including 57 sputum-positive cases, 64 sputum-negative cases, and 42 cases with extrapulmonary tuberculosis, were collected during 2007 and 2009 from the Disease Prevention and Control Center of Deqing County. In addition, 573 controls (224 healthy volunteers, 217 patients with acute pneumonia and bronchitis, 132 patients with paragonimiasis) were recruited for comparison. Mycobacterium tuberculosis specific antibodies were detected by using immunochromatographic and protein chip technique. Detection rate was compared with Chi-square test. RESULTS: Among the 163 tuberculosis patients, the positive rates of immunochromatographic detection and protein chip were 73.0% (120/163) and 72.4% (118/163) respectively; the difference was not statistically significant (χ()2 = 0.062, P > 0.05). Among the 573 controls, the negative rates of immunochromatographic detection and protein chip were 93.9% (538/573) and 92.0% (527/573) respectively; the difference was not statistically significant (χ()2 = 0.635, P > 0.05). There was no cross reaction in the paragonimiasis patients. The positive rate of the immunochromatographic assay was as high as 87.7% (50/57) in the sputum-positive patients. CONCLUSIONS: The double antigen immunochromatographic technique is an easy to operate, rapid, highly sensitive, specific, and reproducible method for the detection of Mycobacterium tuberculosis antibodies.

[Effect of miR-15a on induction of apoptosis in breast cancer MCF-7 cells].

OBJECTIVE: To investigate the effect and mechanism of miR-15a on the induction of apoptosis in breast cancer cells. METHODS: To detect the expression level of miR-15a in breast cancer cell line MCF-7 cells and human mammary gland epithelial cell line MCF-10A cells by quantitative PCR. The target point of MCF-7 was predicted by software and was validated by luciferase report gene system. MiR-15a was transfected into MCF-7 cells with liposomes. The expression of Bcl-2 in MCF-7 cells was detected by Western blotting and the apoptosis rate of MCF-7 cells was detected by flow cytometry. RESULTS: The expression level of miR-15a in MCF-7 cells was lower than that in the MCF-10A cells (0.253:1, P < 0.0001). The expression of MiR-15a was significantly inhibited by Bcl-2 (P < 0.05). Compared with the control, Bcl-2 expression was significantly decreased in the MCF-7 cells. The results of flow cytometry showed that the apoptosis rate was 13.4% in non-transfected MCF-7 cells, 15.9% in MCF-7 cells transfected with control RNA, and 31.5% in MCF-7 cells transfected with miR-15a (P < 0.05), indicating an evident induction of apoptosis in the MCF-7 cells. CONCLUSION: miR-15a may have a potential application value in breast carcinoma biotherapy.