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A steady state and two-dimensional laminar free convection heat transfer in a partitioned cavity with horizontal adiabatic and isothermal side walls is investigated using both experimental and numerical approaches. The experiments and numerical simulations are carried out using a Mach-Zehnder interferometer and a finite volume code, respectively. A horizontal and adiabatic partition, with angle of θ is adjusted such that it separates the cavity into two identical parts. Effects of this angel as well as Rayleigh number on the heat transfer from the side-heated walls are investigated in this study. The results are performed for the various Rayleigh numbers over the cavity side length, and partition angles ranging from 1.5 × 10 to 4.5 × 10, and 0 to 90, respectively. The experimental verification of natural convective flow physics has been done by using FLUENT software. For a given adiabatic partition angle, the results show that the average Nusselt number and consequently the heat transfer enhance as the Rayleigh number increases. However, for a given Rayleigh number the maximum and the minimum heat transfer occurs at θ = 45and θ = 90, respectively. Two responsible mechanisms for this behavior, namely blockage ratio and partition orientation, are identified. These effects are explained by numerical velocity vectors and experimental temperatures contours. Based on the experimental data, a new correlation that fairly represents the average Nusselt number of the heated walls as functions of Rayleigh number and the angel of θ for the aforementioned ranges of data is proposed. [ABSTRACT FROM AUTHOR]

Sm2O3nanoparticles were successfully synthesized from nitrate bath by using a simple cathodic deposition and thermal annealing method for the first time. The shape, size, and phase of the synthesized Sm2O3particles are investigated by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The deposition mechanism and phase transformation during heat-treatment are discussed. The thermal behavior of as-prepared sample has been studied by thermogravimetric analysis (TG, DSC). The results showed that the sample was composed of the nanoparticles with grain size of approximately 30–70 nm. The effects of solution pH on the morphological features of sample are also described. [ABSTRACT FROM AUTHOR]

Abstract: An experimental study was performed to investigate the convective heat transfer coefficient (HTC) of Al2O3–H2O nanofluid using impingement of a fluid jet on a flat circular disk. Nanofluid enhanced the measured HTC values, as compared with the HTC values when using water. Nanofluids, in this case, were prepared with different concentration of nanoparticles in water. The pH of the fluid was adjusted to a desirable value and Sodium Dodecyl Benzene Sulfonate (SDBS) was added to the fluid as a dispersant. These composite fluids were shown to be stable and during experiments no sedimentation was observed. To investigate the effects of the Reynolds number as well as nanoparticle concentration on the local and average HTCs, the Reynolds number was varied in the range of 4200–8200 and the nanoparticle concentration was varied from 0.0198 to 0.0757 wt%. The results showed that, although the nanofluids increased HTCs, the maximum enhancement would correspond to the nanofluid with nanoparticle concentration of 0.0597 wt% and adding more nanoparticles did not prove to be beneficial. In fact the nanoparticle concentration of 0.0757 wt% demonstrated the lowest enhancement in HTC. The maximum enhancement of the average nanofluid HTC in comparison with water is about 50% for Reynolds number of 4200. The average HTC of nanofluids was also remained constant with the increase of Reynolds number due to nanoconvection. [Copyright &y& Elsevier]

This paper presents a new configuration of a dual frequency, single feed, planar inverted-F antenna, which is suitable for implementation in different handsets. A parametric study, using finite element simulation software, high frequency structure simulator, has been carried out on each of the frequencies of this antenna and closed formulas in terms of antenna parameters have been obtained, which makes the designing process much easier. The proposed antenna has been fabricated according to the obtained formulas. Both, numerical simulation and experimental data are presented. [ABSTRACT FROM AUTHOR]

Highlights: [•] Al2O3–water nanofluid with lower concentrations yield positive effects on the heat transfer. [•] The maximum increase in the local heat transfer coefficient is 21.7%. [•] A maximum increase of 13.91% was observed for averaged heat transfer coefficient. [Copyright &y& Elsevier]

Abstract: The effect of pH variation of MWCNT–H2O nanofluid on the efficiency of a flat-plate solar collector was investigated experimentally. The experiments were carried out using 0.2wt.% MWCNT with various pH values, 3.5, 6.5, and 9.5, and Triton X-100 as additive. The procedure of ASHRAE standard was used for testing the thermal performance of flat-plate solar collector. Results show that by increasing or decreasing the pH values with respect to the pH of isoelectric point, the positive effect of nanofluid on the efficiency of solar collector is increased. [Copyright &y& Elsevier]

To improve the mechanical properties, the cobalt ferrocyanide precipitation was carried out on clinoptilolite as an inorganic polymer. In this work the combination of two important factors, stability (zeolite) and high adsorption capacity (cobalt ferrocyanide) were considered to improve the ions uptake ability of adsorbent. The modification was approved by X-ray diffraction, Scanning electronic microscopy and Fourier transform infrared spectroscopy. The modified zeolite was applied to remove Sr(II) and Cs(I) ions from aqueous solution in a batch system. The adsorption capacities of modified zeolite for Cs(I) and Sr(II) improved to 90 and 130 mgg-1, respectively. The Sr(II) and Cs(I) removal were investigated as a function of shaking time, pH, Sr(II), and Cs(I) initial concentration and temperature. The experimental data were fitted well to Langmuir isotherm model for two sorbet metal ions. The time dependence sorption data showed that the uptakes of Cs(I) and Sr(II) were very rapid and apparent sorption equilibriums were achieved within 100 min of contact time. The kinetic experimental data were fitted to the pseudo-first order, pseudo-second order, the double exponential, Elovich and intraparticle diffusion models. The sorption rates and capacities as well as rate constants were evaluated.

Cancer remains a formidable challenge in the field of medicine, necessitating innovative therapeutic strategies to combat its relentless progression. The cell cycle, a tightly regulated process governing cell growth and division, plays a pivotal role in cancer development. Dysregulation of the cell cycle allows cancer cells to proliferate uncontrollably. Therapeutic interventions designed to disrupt the cell cycle offer promise in restraining tumor growth and progression. Telomerase, an enzyme responsible for maintaining telomere length, is often overactive in cancer cells, conferring them with immortality. Targeting telomerase presents an opportunity to limit the replicative potential of cancer cells and hinder tumor growth. Angiogenesis, the formation of new blood vessels, is essential for tumor growth and metastasis. Strategies aimed at inhibiting angiogenesis seek to deprive tumors of their vital blood supply, thereby impeding their progression. Metastasis, the spread of cancer cells from the primary tumor to distant sites, is a major challenge in cancer therapy. Research efforts are focused on understanding the underlying mechanisms of metastasis and developing interventions to disrupt this deadly process. This review provides a glimpse into the multifaceted approach to cancer therapy, addressing critical aspects of cancer biology-cell cycle regulation, telomerase activity, angiogenesis, and metastasis. Through ongoing research and innovative strategies, the field of oncology continues to advance, offering new hope for improved treatment outcomes and enhanced quality of life for cancer patients.

Nanostructure titanium carbide MXene (Ti 3 C 2 Tx) was modified with KH 2 PO 4 and chitosan to effectively remove strontium from nuclear wastewater. Nuclear waste includes radionuclides of uranium, thorium, strontium, and cesium, which are classified depending on the concentration of radionuclides. Nuclear waste with a high strontium concentration is the production waste of radiopharmaceutical production centers. Ti 3 C 2 Tx was synthesized from Ti 3 AlC 2 using HF40% and HF in situ (MILD-Ti 3 C 2 T x ) in 24 h at 313.15 and 333.15 K. Morphology, structure, and functional groups were investigated using the XRD, SEM, EDS, FTIR, and BET analyses. The Sr(II)'s adsorption capacity on Ti 3 C 2 T x -HF and Ti 3 C 2 T x -HF in situ was obtained as 61.9 and 253.5 mg g -1 , respectively (temperature, 298.15 K; pH, 7.00; contact time, 180 min; and Sr(II) concentration, 150 mg l -1 ). Ti 3 C 2 T x -HF in situ showed fourfold adsorption due to more hydroxyl functional groups and larger interlayer spacing. Ti 3 C 2 T x was modified with KH 2 PO 4 and chitosan to investigate the mechanism of change of Sr(II)'s adsorption capacity, which increased to 370 and 284 mg g -1 , respectively. The structural results of modified Ti 3 C 2 T x showed that the surface functional groups increased when modified with chitosan. In addition, modification with KH 2 PO 4 , through encapsulating large amounts of KH 2 PO 4 between Ti 3 C 2 T x layers, increased the possibility of Sr(II) diffusion between layers and electrochemical interactions with hydroxyl groups, and thus, increased its adsorption. Some experiments were designed to investigate the effect of parameters like initial concentration of Sr(II), contact time, temperature, and pH solution, as well as modified- and unmodified-Ti 3 C 2 T x on adsorbent. The results revealed that the adsorption process of Sr(II) with pristine and modified-Ti 3 C 2 T x follows pseudo-second-order kinetics and Freundlich heterogeneous isotherm model. Freundlich model isotherm indicates the presence of various functional groups on the surface and between the pristine and modified Ti 3 C 2 T x layers. Electrostatic reactions and intra-sphere complexation were the two dominant mechanisms of the adsorption process., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Repeated implantation failure (RIF) refers to the condition where high quality embryos are unable to successfully implant after multiple cycles of in vitro fertilization (IVF) treatment. The aim of this study is to investigate the impact of intrauterine granulocyte colony-stimulating factor (G-CSF) and platelet-rich plasma (PRP) on pregnancy rate in patients with RIF., Materials and Methods: The present randomised clinical trial study was conducted at the IVF Centre of Mehr Medical Institute in Rasht, Iran, from 2020 to 2022. The research consisted of 200 individuals who had experienced multiple failed cycles. These patients were randomised into two groups: intrauterine infusion of 1 ml of G-CSF and intrauterine infusion of 1 ml autologous PRP at least 48 hours before embryo transfer (ET). The groups were compared in terms of implantation rate, and chemical, clinical, and ongoing pregnancy., Results: The implantation rate was significantly higher in patients who received PRP (P=0.016). Chemical pregnancy in the PRP group was significantly higher than G-CSF group (P=0.003). Both clinical pregnancy and ongoing pregnancy rates were significantly higher in the PRP group (P=0.001) compared to the G-CSF group (P=0.02)., Conclusion: The utilisation of PRP via intrauterine infusion is considerably more successful than G-CSF in enhancing pregnancy and live birth rates among patients with RIF.

Synovial sarcoma, a rare soft tissue malignancy typically arising from synovial tissue, primarily manifests in the extremities but it may uncommonly present in other locations such as kidneys. Primary renal synovial sarcoma is an uncommon sarcoma with high mortality and recurrence rates. Here, we present a teenage boy with primary renal synovial sarcoma who was referred to our institution., Competing Interests: The authors declare no conflict of interest., (© 2024 The Authors.)