Iodine/β-cyclodextrin (iodine/β-CD) inclusion complex was prepared via a simple saturated water solution route. The truncated cone-shaped and hydrophobic central cavity structure of β-CD could ...effectively encapsulate iodine molecules to confine the iodine within the electrode. The Li-iodine battery with iodine/β-CD cathode delivers the initial specific discharge capacity of 175 mAh g
−1
at 0.1 C, and remains 164 mAh g
−1
after 300 cycles owing to the favorable distribution and the retention of the iodine in the truncated cone-shaped β-CD matrix. Results demonstrate that β-CD as host electrode material could improve the stability of iodine-based cathode, showing great potential as a low-cost and facile cathode in Li-iodine batteries.
Over the past decade, TiO2/graphene composites as electrodes for lithium ion batteries have attracted a great deal of attention for reasons of safety and environmental friendliness. However, most of ...the TiO2/graphene electrodes have large graphene content (9–40 %), which is bound to increase the cost of the battery. Logically, reducing the amount of graphene is a necessary part to achieve a green battery. The synthesis of TiO2 nanosheets under solvothermal conditions without additives is now demonstrated. Through mechanical mixing TiO2 nanosheets with different amount of reduced graphene (rGO), a series of TiO2@graphene composites was prepared with low graphene content (rGO content 1, 2, 3, and 5 wt %). When these composites were evaluated as anodes for lithium ion batteries, it was found that TiO2+3 wt % rGO manifested excellent cycling stability and a high specific capacity (243.7 mAh g−1 at 1 C; 1 C=167.5 mA g−1), and demonstrated superior high‐rate discharge/charge capability at 20 C.
Cogito rGO sum: TiO2 nanosheets with different amounts of reduced graphene (rGO) were prepared with low rGO content (1, 2, 3, and 5 wt %). When these TiO2@graphene composites were evaluated as anodes for lithium ion batteries, TiO2+3 wt % rGO manifested excellent cycling stability and a high specific capacity (243.7 mAh g−1 at 1 C; 1 C=167.5 mA g−1), and demonstrated superior high‐rate discharge/charge capability at 20 °C.
Mercury is usually added to skin-lightening products due to its whitening effect.The Food and Drug Administration （FDA） limits the amount of mercury in cosmetics to trace amounts under 1 ...ppm.Nevertheless,many cosmetics contain mercury above 1000 ppm to increase the whitening effect.In a group of special patients in the study,pain,renal damage,and neuropsychiatric symptoms were the cardinal symptoms observed.
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•SmMn2O5 nanocrystals are synthesized by a tunable hydrothermal route.•The pH value of precursor solution is a decisive factor for morphology control.•The nanoparticles exhibit better ...catalytic activity for NO oxidation than nanorods.•The ability of surface oxygen adsorption is responsible for the performance improvement.
SmMn2O5 has been reported to be a promising alternative to substitute the current commercial Pt-based catalysts for NO oxidation. In this work, single-crystalline orthorhombic SmMn2O5 nanorods and nanoparticles are successfully synthesized through a tunable hydrothermal route. The pH value of the precursor solution is a decisive factor for morphology control of SmMn2O5 nanocrystals, with decreasing pH value the morphology of SmMn2O5 nanocrystals converts from nanoparticles to nanorods. The nanoparticles exhibit a better catalytic activity for NO oxidation than the nanorods, because they can efficiently convert NO at lower temperature. By the analysis of X-ray photoelectron spectrum and high-resolution transmission electron microscope, the oxidation activity is found to be dependent on the high specific surface area and surface crystal planes of SmMn2O5 nanocrystals, which widens and deepens the oxygen chemistry and NO oxidation mechanism on the surfaces of SmMn2O5. This work could not only provide new insights into the morphology control of SmMn2O5 nanocrystals, but also pave a new way for the crystal planes modification of SmMn2O5 nanocrystals as NO oxidation catalyst to achieve an enhanced performance for environmental applications.
MicroRNA-34a (miR-34a) functions as a tumor suppressor gene and inhibits abnormal cell growth by regulating the expression of other genes. The role of miR-34a in regulating sirtuin 1 (SIRT1) in ...prostate cancer remains unclear. The objective of the present study was to investigate the biological function and molecular mechanisms of miR-34a regulation of SIRT1 in human prostate cancer samples and the human prostate cancer cell line, PC-3. Fresh prostate tissues were obtained from patients, and the miR-34a expression in prostate cancer tissues was measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). qPCR and western blotting were performed to assess the effects of miR-34a overexpression on SIRT1 regulation in PC-3 cells, and the cell growth was assessed by Cell Counting Kit-8 (CCK-8). Flow cytometry was used to assess the cell cycle status of the cells. The miR-34a expression levels in prostate cancer tissues were significantly reduced compared with adjacent normal prostate tissues (P<0.05). SIRT1 expression levels in PC-3 cells with over-expression of miR-34a were significantly reduced compared with those in the negative control (P<0.05). The over-expression of miR-34a inhibited PC-3 cells growth and resulted in increased cell cycle arrest compared with the negative control (P<0.05). In conclusion, miR-34a inhibits the human prostate cancer cell proliferation, in part, through the downregulation of SIRT1 expression.
Aligned zinc oxide nanorods were synthesized directly via a two-step solution approach on an Al
2O
3 tube, and were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). ...The zinc oxide nanorods prepared were uniform with diameters of 10–30
nm and lengths about 1.4
μm. The response
S
r (=
R
a/
R
g) of the aligned zinc oxide nanorod sensor reached 18.29 and 10.41 to 100
ppm ethanol and hydrogen, respectively, which was a two-fold increase compared with that reported in literature, demonstrating the potential for developing stable and sensitive gas sensors.
•The sea urchin-like SmMn2O5/MnO2 is synthesized by a tunable hydrothermal route.•The SmMn2O5/MnO2 shows better ORR catalytic activity than pure phase SmMn2O5.•The pyramidal Mn3+ and surface oxygen ...adsorption capacity are responsible for ORR activity.•Zn-air battery made with SmMn2O5/MnO2 exhibits high power density and durability.
In this work, sea urchin-like SmMn2O5/MnO2 is synthesized by the hydrothermal method. Compared with SmMn2O5, SmMn2O5/MnO2 has a half wave potential of 0.82 V (vs RHE), which shows excellent electrocatalytic activity of oxygen reduction reaction (ORR) in the alkaline media. More importantly, the composite of SmMn2O5/MnO2 shows higher number of electron transfers, better stability of ORR, and stronger methanol-tolerant ability comparison with the commercial catalyst of Pt/C. The remarkable ORR activity is due to the formation of abundant oxygen vacancies and Mn3+, which are beneficial to the adsorption of oxygen species and the activation of O-O bond. The sea urchin-like morphology increases the specific surface area, and the tip-like synapses play an essential role in charge accumulation and rapid transfer. Moreover, the rechargeable zinc-air battery made of SmMn2O5/MnO2 not only has a high peak power density, but also has excellent cycle stability of 450 h in long-term charge discharge measurement.
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In this work, the ordered nanoporous arrays of Au and Pt films are fabricated using anodized aluminum oxide (AAO) template based on the sputtering method. The presented synthetic strategy is scalable ...to large area by incorporating the deposition of a thin layer of Au or Pt. In addition, the grain size of Au and Pt nanoporous films is controlled with sputtering time. The thorough study of electrical transport properties for these metal films enables us to infer the nanoporous film morphology, and the evolution of the grain size with the change of sputtering time. In fact, the different physical behaviors are observed to occur in these metal films. The negative temperature coefficient of resistance (TCR) is visible for Pt nanoporous films, while Au nanoporous films show the positive TCR. With the increasing of sputtering time, the Pt grain size gradually becomes bigger, and the negative TCR properties weaken because the interface scattering of the electrons reduces. Therefore, the fabrication of metal nanoporous films with well-controlled physical properties might open new pathways for the growth of metal electrodes on AAO substrates for nanoelectronic devices.
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