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Ni-rich layered oxides LiNi1–x–yMnxCoyO2(NMC811, x= 0.1 and y= 0.1) are considered promising cathode materials in lithium-ion batteries (LiBs) due to their high energy density. However, those suffer a severe capacity loss upon cycling at high delithiated states. The loss of performance over time can be retarded by Zr doping. Herein, a small amount of Zr is added to NMC811 material via two alternative pathways: during the formation of the transition metal (TM) hydroxide precursor at the co-precipitation step (0.1%-Zr-cp) and during the lithiation at the solid-state synthesis step (0.1%-Zr-ss). In this work, the crystallographic Zr uptake in both 0.1%-Zr-ss and 0.1%-Zr-cp is determined and quantified through synchrotron X-ray diffraction and X-ray absorption spectroscopy. We prove that the inclusion of Zr in the TM site for 0.1%-Zr-cp leads to an improvement of both specific capacity (156 vs 149 mAh/g) and capacity retention (85 vs 82%) upon 100 cycles compared to 0.1%-Zr-ss where the Zr does not diffuse into the active material and forms only an extra phase separated from the NMC811 particles.

ABSTRACTDifferent compositions of manganese (x = 1 & 3 wt. %) and nitrogen (y = 1 wt. %) co-doped TiO2(MnxNyT) photocatalysts are prepared by the conventional sol-gel method. The crystallinity, optical properties, phase purity and surface morphology of prepared nano-photocatalysts were characterised in detail. The structural analyses show that the simultaneous doping with manganese and nitrogen controls the growth of TiO2crystal structure having an average crystallite size in the range of 14.6 to 24.5 nm. The optical analysis also demonstrated that due to the synergistic effect of Mn and N, co-doped TiO2represents the red-shift in the absorption band edge from 3.33 eV to 2.39 eV, which improved the response of TiO2structure towards the visible region and enhanced electron-hole separation. Among all, Mn3N1T represented the better photocatalytic efficiency against anionic dyes (Blue KBR and Red GD) and phenol under optimised conditions (such as initial substrate’s concentration = 20 ppm, photocatalyst dose = 0.5 g and solution pH of 3 and 7, respectively) due to its low bandgap, low crystallite size and high absorptivity towards the visible region. The kinetics study also showed that the degradation of dyes and phenol over Mn3N1T followed pseudo-first-order kinetics.

The aim of this paper is to introduce a class of generalized Suzuki type $$ (\alpha _{*},\psi _{\varphi })$$ (α∗,ψφ) -contractive multivalued operators and to prove the existence of fixed point and common fixed point of such operators in the setup of b-metric spaces. Some examples are presented to support the results proved herein. Our results generalize and extend various results in the existing literature. An estimate of Hausdorff distance between the fixed point sets of two generalized Suzuki type $$(\alpha _{*},\psi _{\varphi })$$ (α∗,ψφ) -contractive multivalued operators is obtained. We further investigate the Ulam–Hyers stability of fixed point problem of operators considered herein in the framework of b-metric spaces.

Children are more susceptible to intubation related injuries than adults. It could be as minor as mild laryngeal edema to fatal airway obstruction. Repeated attempts at intubation in paediatric patients secondary to difficult airway or nonoptimal intubating conditions may lead to catastrophic complications. Surgery was scheduled for a 3-month-old infant with lumbar myelomeningocele. After inhalational induction, repeated intubation attempts resulted in laryngeal edema. i-gel® was then inserted, and the appropriate management was followed to reduce the edema. Here, we report a near fatal event in the form of laryngeal edema in an infant posted for meningocele repair. Proper titration of depth of inhalational anaesthesia is essential to avoid repeated attempts at laryngoscopy and subsequent complications.

The aim of this paper is to introduce a new type of generalized multivalued contraction mappings and to present some results regarding fixed points of new class of multivalued contractions. As applications we obtain some basic results in fixed point theory like characterization of metric completeness, data dependence of fixed points and homotopy result. We prove the existence and uniqueness of bounded solution of functional equation arising in dynamic programming. Our results generalize, extend and unify various comparable results in the existing literature.

In this article, we introduce a new type of generalized multivalued Hardy and Roger’s type proximal contractive and proximal cyclic contractive mappings of b-metric spaces and develop some results for the existence of best proximity point(s). Moreover, we obtain some results for the existence and uniqueness of best proximity points for single-valued mappings. Examples are given to explain the main results.

Highly conductive Mo2C networks were embedded with uniformly stacked MoS2nanosheets via a hydrothermal reaction. The fabricated interfacial MoS2@Mo2C hybrid nanostructures were systematically ascertained by X-ray diffraction, Raman spectroscopy, FESEM-EDS and high-resolution transmission electron microscopy. Further, the high-magnification TEM image reveals the fingerprint-structured grains stacked on the MoS2lattice, while its high-resolution zoom-in image proves the lattice arrangements. The enhanced BET area of 7.21 m2 g−1is found for the MoS2@Mo2C hybrid compared to the MoS2(2.04 m2 g−1) and Mo2C (0.83 m2 g−1). The designed MoS2@Mo2C nano-architecture anode provided the rescindable capacity of 210 mAh g−1at a 50 mA g−1current density for lithium ion batteries. In addition, MoS2@Mo2C retained a capacity of 150 mAh g−1after 100 cycles at 50 mA g−1with more than 98% of Coulombic efficiency, indicating outstanding cycling stability. The fabricated MoS2@Mo2C hybrid produced improved behavior, compared with that of the bare Mo2C and MoS2 anode. The exceedingly conductive nature of Mo2C and its well interacted relation with the MoS2nanoparticles which prevented the restacking of MoS2sheets thereby facilitated fast electron/ion transfer, yielding excellent rate capability. The unique hierarchical structural of MoS2@Mo2C makes it a prospective material for high-performing lithium ion battery anode.

The Government of Pakistan introduced smoking ordinance about health warning in 2009. This ordinance exhibits, prohibit smoking in public places, put restrictions on advertisements, and prohibits sale of cigarettes to minors. This study is to find out the impact of smoking expenditures on food, health, educational, recreational, and electronic expenditures using HIES dataset for 2010–11 and 2015–16. The findings show that share of food and health expenditure increase by 91 and 92% respectively. On the other hand, education and recreation expenditure decrease by 6 and 98% respectively. This is further verified using SUEST test to compare two datasets regressions. The result reveals that food, health, and recreational coefficient are statistically different while education and electronics expenditure remain similar.