ABSTRACT
The practical application of lithium-sulfur batteries (LSBs) is still hindered by several technical issues, including severe polysulfide shuttling and sluggish redox kinetics, which reduces the sulfur utilization and further results in low energy density. Herein, amorphous-crystalline heterostructured MnO2 (ACM) prepared through a simple calcination process was employed as the functional interlayer to play a double role as effective trapper and multifunctional electrocatalyst for LSBs. ACM not only combines the strong sulfur chemisorption of the amorphous MnO2 (AM) and fast Li+ transportation of the crystalline MnO2(CM) but also accelerates the interface charge transfer at the amorphous/crystalline interfaces. The LSBs with such unique interlayer exhibited an excellent rate performance of 1155.5 mAh·g-1 at 0.2 C and 692.9 mAh·g-1 at 3 C and a low decay rate of 0.071% per cycle over 500 cycles at 0.5 C. Even for a high sulfur loading of 5 mg·cm-2 at 0.1 C, a high capacity retention of 92.3% could also be achieved after 100 cycles. The concept of amorphous-crystalline heterostructures prepared by crystallization regulation might also be used for other electronic devices and catalyst designs.
ABSTRACT
OBJECTIVE: To explore the relation of cytogenetic changes in patients with chronic myeloid leukemia (CML) to the diagnosis, clinical staging and therapy protocol of the disease. METHODS: According to established diagnostic criteria, 155 CML patients were divided into 3 groups and 3 clinical phases were identified on the basis of their Sokal scores. The bone marrow was obtained for G banding and karyotype analysis. RESULTS: It was found that 148 patients (95.5%) carried Ph1 chromosome. Among the other 7 cases without Ph1 chromosome, 4 were identified as being bcr/abl fusion gene positive. The ratio of additional cytogenetic abnormalities were higher in patients in blast crisis or accelerated phase than in patients in chronic phase. CONCLUSION: CML consists of a group of diseases with high heterogeneity, and the prognoses of the patients mostly depend on the malignancy of the tumor. The occurrence of additional chromosomal abnormality is highly correlative with the risk index and clinical staging of the patients, which may serve prognostic purposes. Conventional cytogenetic analysis may help evaluate the therapeutic effect and make subsequent clinical decisions, and may also facilitate new karyotype identification.
