Fabrication and investigation of thermal and wear properties of zinc novel coati ngs reinforced with nano-Al2O3 and Cr2O3 pa rticles

The study of the thermal, wear and corrosion properties of developed nanocomposite coatings of Zn-Al2O3 and Zn- Cr2O3 was carried out. The coatings were produced by electrodeposition technique from chloride acidic bath. Laboratory tube furnace was used for the thermal analysis. The wear test was performed using CETR tribo-tester dry reciprocating tester. The hardness properties were investigated using diamond base Dura microhardness tester. Scanning electron microscope (SEM) affixed with energy dispersive spectrometry was used to study the morphological characteristics, before and after wear deformation. The corrosion degradation behavior was observed using linear polarization technique in 3.5% NaCl. In all the interaction, the effects of the incorporated Al2O3 and Cr2O3nanoparticulates on zinc rich coatings were found to have an excellent influence on the wear, corrosion and thermal stability properties. The fabrication and properties exhibited by the alloys were therefore found to be satisfactory and shows good predictability and applicabilit

The effect of nanoparticulate loading on the fabrication and characterization of multi-doped Zn-Al2O3-Cr2O3 hybrid coatings on mild steel

Nanoparticle Al2O3/Cr2O3 was successfully incorporated into Zn rich by electrodeposition technique to produce Zn-Al2O3-Cr2O3 ternary coatings. The morphology and structural characteristics of the fabricated electrodeposits were characterized by scanning electron microscopy (SEM) affixed with energy-dispersive spectroscopy and X-ray diffraction. The electrochemical behavior of the coatings was studied by potentiodynamic polarization. The wear and microhardness properties of the coatings were tested using ball-ondisk sliding wear tester and diamond base microhardness indenter, respectively. The results showed that the incorporation of the nanoparticles into the Zn matrix refines the morphology and modifies the crystallographic orientation of the Zn coatings. The nanocomposite coatings exhibited improved microhardness properties, wear resistance, and thermal stability. Corrosion studies revealed that the incorporation of the mixed-oxide nanoparticles has no significant effect on the corrosion resistance of Zn coating

Fabrication and Properties of Zinc Composite Coatings for Mitigation of Corrosion in Coastal and Marine Zone

Deterioration of metals and alloys during service due to corrosion and wear phenomena shortens materials’ life span and structural integrity particularly in aggressive environments such as coastal and marine. This degradation also limits the use of these materials in most industrial applications. Therefore, the improvement of the quality of these materials in order to combat these challenges in industry remains critical. Surface modification techniques are employed to enhance materials’ properties to enable better performance and to extend their applications in demanding environments. Electrodeposition has been a useful method developed to improve the corrosion and mechanical properties of materials. In the present contribution, ample knowledge about electrodeposition of Zn composite/ nanocomposite coatings and their characteristics are reviewed to address coastal and marine degradation of metals and alloys

The effects of absenteeism on nurses remaining on duty at a tertiary hospital of Limpopo province

Background: Absenteeism is a global problem in the working force and this is no exception in the nursing profession. Much attention has been drawn to factors that contribute to absenteeism; however, little attention has been placed on the effects of absenteeism on nurses remaining on duty by their colleagues. Nurses absent themselves leaving behind their colleagues to execute their part of work. Objectives: To investigate the effects of absenteeism on nurses who remained on duty at a tertiary hospital in Limpopo province. Method: A quantitative descriptive research approach was chosen to enable the researchers to achieve the research aim. Data collected using structured questionnaires were analysed by descriptive statistics. Results: The findings indicated that absenteeism has an effect on both the nurses’ psychological and professional well-being, as well as the quality of patient care provided as a result of psychological stress, low morale of nurses and increased workload. The study further revealed the provision of substandard care to patients by those nurses who are remaining on duty, resulting in risk of medical errors that could jeopardise their professional credibility. Therefore, absenteeism creates an unhealthy working environment for nurses remaining on duty. Conclusion: Nurse managers should provide platforms to address psychological and professional problems experienced by nurses remaining on duty. The study further recommends the introduction of policies that would address absenteeism in the workplace and how nurses who remain on duty could be assisted with the workload of colleagues who continuously absent themselves

Nuclear Level Density and γ\gamma-ray Strength Function of 67Ni^{67}\mathrm{Ni} and the impact on the i-process

Proton-$\gamma$ coincidences from $(\mathrm{d},\mathrm{p})$ reactions between a $^{66}\mathrm{Ni}$ beam and a deuterated polyethylene target have been analyzed with the inverse Oslo method to find the nuclear level density (NLD) and $\gamma$-ray strength function ($\gamma$SF) of $^{67}\mathrm{Ni}$. The $^{66}\mathrm{Ni}(\mathrm{n},\gamma)$ capture cross section has been calculated using the Hauser-Feshbach model in TALYS using the measured NLD and $\gamma$SF as constraints. We confirm that $^{66}\mathrm{Ni}(\mathrm{n},\gamma)$ acts as a bottleneck when relying on one-zone nucleosynthesis calculations. However, we find that the impact of this reaction is strongly damped in multi-zone low-metallicity AGB stellar models experiencing i-process nucleosynthesis.Comment: Submitted to Phys. Rev.

Multifaceted incorporation of Zn-Al2O3/Cr2O3/SiO2 nanocomposite coatings: anti-corrosion, tribological, and thermal stability

Nano-sized particle incorporation into metal matrix has gained worldwide acceptance. Al2O3, Cr2O3, and SiO2 nanoparticles have been co-deposited with Zn using electrodeposition process to produce advanced alloy. The coatings were characterized using SEM/EDX and XRD. The mechanical properties of the coatings were studied using microhardness indenter and dry abrasive wear tester. Zn-10 g/L Cr2O3 nanocomposite exhibited the highest microhardness of 228 HVN; Zn-5 g/L Al2O3 nanocomposite possessed the highest corrosion resistance and lowest wear loss. Zn-5 g/L SiO2 nanocomposite showed good stability against other composite coatings. The incorporation of the Al2O3, Cr2O3, and SiO2 shows grain refinement and modify orientation on Zn matrix

β and γ bands in N = 88 , 90, and 92 isotones investigated with a five-dimensional collective Hamiltonian based on covariant density functional theory : vibrations, shape coexistence, and superdeformation

CITATION: Majola, S. N. T. et al. 2019. β and γ bands in N=88, 90, and 92 isotones investigated with a five-dimensional collective Hamiltonian based on covariant density functional theory: Vibrations, shape coexistence, and superdeformation. Physical Review C, 100(4). doi:10.1103/PhysRevC.100.044324.The original publication is available at https://journals.aps.org/prc/A comprehensive systematic study is made for the collective β and γ bands in even-even isotopes with neutron numbers N = 88 to 92 and proton numbers Z = 62 (Sm) to 70 (Yb). Data, including excitation energies, B(E0) and B(E2) values, and branching ratios from previously published experiments are collated with new data presented for the first time in this study. The experimental data are compared to calculations using a five-dimensional collective Hamiltonian (5DCH) based on the covariant density functional theory (CDFT). A realistic potential in the quadrupole shape parameters V (β,γ ) is determined from potential energy surfaces (PES) calculated using the CDFT. The parameters of the 5DCH are fixed and contained within the CDFT. Overall, a satisfactory agreement is found between the data and the calculations. In line with the energy staggering S(I) of the levels in the 2γ + bands, the potential energy surfaces of the CDFT calculations indicate γ -soft shapes in the N = 88 nuclides, which become γ rigid for N = 90 and N = 92. The nature of the 02 + bands changes with atomic number. In the isotopes of Sm to Dy, they can be understood as β vibrations, but in the Er and Yb isotopes the 02 + bands have wave functions with large components in a triaxial superdeformed minimum. In the vicinity of 152Sm, the present calculations predict a soft potential in the β direction but do not find two coexisting minima. This is reminiscent of 152Sm exhibiting an X(5) behavior. The model also predicts that the 03 + bands are of two-phonon nature, having an energy twice that of the 02 + band. This is in contradiction with the data and implies that other excitation modes must be invoked to explain their origin.https://journals.aps.org/prc/abstract/10.1103/PhysRevC.100.044324Publisher’s versio

Fabrication and Investigation of Thermal and Wear Properties of Zinc Novel Coatings Reinforced with Nano-Al2O3 and Cr2O3 Particles

The study of the thermal, wear and corrosion properties of developed nanocomposite coatings of Zn-Al2O3 and Zn-Cr2O3 was carried out. The coatings were produced by electrodeposition technique from chloride acidic bath. Laboratory tube furnace was used for the thermal analysis. The wear test was performed using CETR tribo-tester dry reciprocating tester. The hardness properties were investigated using diamond base Dura microhardness tester. Scanning electron microscope (SEM) affixed with energy dispersive spectrometry was used to study the morphological characteristics, before and after wear deformation. The corrosion degradation behavior was observed using linear polarization technique in 3.5% NaCl. In all the interaction, the effects of the incorporated Al2O3 and Cr2O3nanoparticulates on zinc rich coatings were found to have an excellent influence on the wear, corrosion and thermal stability properties. The fabrication and properties exhibited by the alloys were therefore found to be satisfactory and shows good predictability and applicability

Improvement on the fabrication of SiC materials: Processing, reinforcing phase, fabricating route—A review

Abstracts: The ceaseless exploration for the improvement of ceramic materials has created a lot of techniques, all aimed at producing ceramic materials that can withstand environmental conditions and other factors. Most of thecommon techniques have their advantages and drawbacks. Some of the techniques involve the addition of a reinforcing phase to monolithic ceramic, the application of diverse sintering routes for the fabrication of ceramic products, and the preparatory methods for producing powder materials which cannot be jettisoned. These processes have been evaluated to influence the final ceramic products. Undoped/monolithic/single-phase ceramic has had some limitations in its processing, densification, and mechanical properties limiting its wide application in all circumstances. Hence, the incorporation of reinforcing phase, which can sometimes be called the secondary phase in the ceramic matrix, has significantly evolved into one of the possible means to nullify these challenges posed by undoped ceramics. This review consciously highlights and pinpoints all routes that have been taken to improve the properties of undoped SiC via the introduction of reinforcing phase, processing techniques, sintering techniques, etc. Finally, the possible prospects for future directions, advancement, and opportunities in the production of ceramic materials are concluded