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This paper aims to introduce an alternative for modeling levitation forces between NdFeB magnets and bulks of high-temperature superconductors (HTS). The presented approach should be evaluated through two different formulations and compared with experimental results.

The T-A and H-ϕ formulations are among the most efficient approaches for modeling superconducting materials. COMSOL Multiphysics was used to apply them to magnetic levitation models and predict the forces involved.The permanent magnet movement is modeled by combining moving meshes and magnetic field identity pairs in both 2D and 3D studies.

It is shown that it is possible to use the homogenization technique for the T-A formulation in 3D models combined with mixed formulation boundaries and moving meshes to simulate the whole device’s geometry.

The case studies are limited to the formulations’ implementation and a brief assessment regarding degrees of freedom. The intent is to make the simulation straightforward rather than establish a benchmark.

The H-ϕ formulation considers the HTS bulk domain as isotropic, whereas the T-A formulation homogenization approach treats it as anisotropic. The originality of the paper lies in contrasting these different modeling approaches while incorporating the external magnetic field movement by means of the Lagrangian–Eulerian method.

This study aims to systematically review the health risk assessment of the concentration of heavy metals in Pistacia species globally.

The authors systematically searched PubMed, Science Direct, Scopus and Google Scholar to identify all articles published between 1 January 2002 and 20 August 2022. A total of 33 studies met the authors’ inclusion criteria, and their data were extracted. Additionally, the potential risk to human health was assessed by calculating the target hazard quotient and hazard index for both child and adult consumers.

The estimated daily intake for heavy metals in the included studies ranged from 9.72 × 10^–9 to 7.35 (mg/day) in the following order: zinc (Zn) > mercury (Hg) > iron (Fe) > lead (Pb) > copper (Cu) > aluminum (Al) > nickel (Ni) > chromium (Cr) > manganese (Mn) > cadmium (Cd) > arsenic (As) > selenium (Se) > cobalt (Co). Among the studies that investigated heavy metals in Pistacia species around the world, the non-carcinogenic risk for all species of Pistacia was determined to be less than 1, except for Pb and Hg in Pistacia lentiscus.

The soil near the industrial area contained excessive amounts of heavy metals, which led to the transfer of heavy metals to plants. Owing to the insufficiency of the number of studies that examined heavy metals in Pistacia species, further monitoring and investigations were recommended.

Policing requires atypical work hours. The present study examined associations between shiftwork and pregnancy loss among female police officers.

Participants were 91 female officers with a prior history of at least one pregnancy. Shiftwork information was assessed using daily electronic payroll work records. Any prior pregnancy loss (due to miscarriage) was self-reported. Logistic regression estimated odds ratios (OR) and 95% confidence intervals (CI) for main associations.

On average, the officers were 42 years old, had 14 years of service, and 56% reported a prior pregnancy loss. Officers who worked dominantly on the afternoon or night shift during their career had 96% greater odds of pregnancy loss compared to those on day shift (OR = 1.96, 95% CI:0.71–5.42), but the result was not statistically significant. A 25% increase in percent of hours worked on night shift was associated with 87% increased odds of pregnancy loss (OR = 1.87, 95% CI:1.01–3.47). Associations were adjusted for demographic and lifestyle factors. Objective assessment of shiftwork via electronic records strengthened the study. Limitations include small sample size, cross-sectional design and lack of details on pregnancy loss or the timing of pregnancy loss with regard to shiftwork.

The present study is preliminary and cross-sectional.

With considerable further inquiry and findings into this topic, results may have an impact on police policy affecting shift work and pregnant police officers.

Implication on the health and welfare of police officers.

To our knowledge, there are no empirical studies which associate shiftwork and pregnancy loss among police officers. This preliminary study suggested an association between shiftwork and increased odds of pregnancy loss and points out the need for further study.

Titanium dioxide (TiO₂) has high opacity, high brightness and whiteness, owing to its high refractive index value. It is mainly used in the coating industry and continuous efforts have been made to replace some of the TiO₂ in paint with new pigments. This study aims to replace part of TiO₂ pigment with various percentages of BaSO₄, CaCO₃ and kaolin in styrene butyl acrylate-based paint formulations, without changing the properties of paints using only titanium dioxide.

To determine the optimum use rate of new pigment mixing, opacity, gloss, scrub resistance and weather resistance properties have been investigated in the water-based paint formulation. The morphological properties of these samples were examined by scanning electron microscopy analysis.

In the total color change (ΔE) measurements, it was observed that the sample coded 85Ti/15Ba produced extremely similar results to the situation when TiO₂ was used alone. It was seen that the best results were obtained when 85Ti/15Ba was used instead of TiO₂.

Comparison research on the impact of replacing TiO₂ with BaSO₄, CaCO₃ and kaolin on the performance characteristics of water-based styrene butyl acrylate-based paint formulations has not been done in the literature, according to the literature search.

The purpose of this paper is to design and manufacture an intelligent 3D printed sensor to monitor the re-occurrence of diaphragmatic hernia (DH; after surgery) in bovines as an Internet of Things (IOT)-based solution.

The approach used in this study is based on a bibliographic analysis for the re-occurrence of DH in the bovine after surgery. Using SolidWorks and ANSYS, the computer-aided design model of the implant was 3D printed based on literature and discussions on surgical techniques with a veterinarian. To ensure the error-proof design, load test and strain–stress rate analyses with boundary distortion have been carried out for the implant sub-assembly.

An innovative IOT-based additive manufacturing solution has been presented for the construction of a mesh-type sensor (for the health monitoring of bovine after surgery).

An innovative mesh-type sensor has been fabricated by integration of metal and polymer 3D printing (comprising 17–4 precipitate hardened stainless steel and polyvinylidene fluoride-hydroxyapatite-chitosan) without sacrificing strength and specific absorption ratio value.

The purpose of this paper is to study the reliability of sintered nano-silver joints on bare copper substrates during high-temperature storage (HTS).

In this study, HTS at 250 °C was carried out to investigate the reliability of nano-silver sintered joints. Combining the evolution of the microstructure and shear strength of the joints, the degradation mechanisms of joints performance were characterized.

The results indicated that the degradation of the shear properties of sintered nano-silver joints on copper substrates was attributed to copper oxidation at the silver/copper interface and interdiffusion of interfacial elements. The joints decreased by approximately 57.4% compared to the original joints after aging for 500 h. In addition, severe coarsening of the silver structure was also an important cause for joints failure during HTS.

This paper provides a comparison of quantitative and mechanistic evaluation of sintered silver joints on bare copper substrates during HTS, which is of great importance in promoting the development of sintered silver technology.

This paper aims to find a suitable solution to degrade the C.I. Reactive Red 24 (RR24) dyeing wastewater by using sodium persulphate to recycle water and inorganic salts.

The effects of temperature, the concentration of inorganic salts and Na₂CO₃ and the initial pH value on the degradation of RR24 were studied. Furthermore, the relationship between free radicals and RR24 degradation effect was investigated. Microscopic routes and mechanisms of dye degradation were further confirmed by testing the degradation karyoplasmic ratio of the product. The feasibility of the one-bath cyclic dyeing in the recycled dyeing wastewater was confirmed through the properties of dye utilization and color parameters.

The appropriate conditions were 0.3 g/L of sodium persulphate and treatment at 95°C for 30 min, which resulted in a decolorization rate of 98.4% for the dyeing wastewater. Acidic conditions are conducive to rapid degradation of dyes, while ·OH or SO₄⁻· have a destructive effect on dyes under alkaline conditions. In the early stage of degradation, ·OH played a major role in the degradation of dyes. For sustainable cyclic dyeing of RR24, inorganic salts were reused in this dyeing process and dye uptake increased with the times of cycles. After the fixation, some Na₂CO₃ may be converted to other salts, thereby increasing the dye uptake in subsequent cyclic staining. However, it has little impact on the dye exhaustion rate and color parameters of dyed fabrics.

The recommended technology not only reduces the quantity of dyeing wastewater but also enables the recycling of inorganic salts and water, which meets the requirements of sustainable development and clean production.

In this paper the aim is that Aramid/alginate blended nonwoven fabrics were prepared, and the flame retardancy of the blended nonwoven fabrics was studied by thermogravimetric analysis, vertical flame test, limiting oxygen index (LOI) and cone calorimeter test.

The advantages of different fibers can be combined by blending, and the defects may be remedied. The study investigates whether incorporating alginate fibers into aramid fibers can enhance the flame retardancy and reduce the smoke production of prepared aramid/alginate blended nonwoven fabrics.

Thermogravimetric analysis indicated that alginate fibers could effectively inhibit the combustion performance of aramid fibers at a higher temperature zone, leaving more residual chars for heat isolation. And vertical flame test, LOI and cone calorimeter test testified that the incorporation of alginate fibers improved the flame retardancy and fire behaviors. When the ratio of alginate fibers for aramid/alginate blended nonwoven fabrics reached 80%, the incorporation of alginate fibers could notably decreased peak-heat release rate (54%), total heat release (THR) (29%), peak-smoke production rate (93%) and total smoke production (86%). What is more, the lower smoke production rate and lower THR of the blends vastly reduced the risk of secondary injury in fires.

This study proposes to inhibit the flue gas release of aramid fiber and enhance the flame retardant by mixing with alginate fiber, and proposes that alginate fiber can be used as a biological smoke inhibitor, as well as a flame retardant for aramid fiber.