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In the printing and textile industries, methylene blue (a cationic azo dye) is commonly used. MB is a well-known carcinogen, and another major issue is its high content in industrial discharge. There are numerous removal methodologies that have been employed to remove it from industrial discharge; however, these current modalities have one or more limitations. In this research, a novel magnetized biochar (γ-Fe2O3-LSB) was synthesized using Lagenaria siceraria peels which were further magnetized via the co-precipitation method. The synthesized γ-Fe2O3-LSB was characterized using FTIR, X-ray diffraction, Raman, SEM–EDX, BET, and vibrating sample magnetometry (VSM) for the analysis of magnetic properties. γ-Fe2O3-LSB showed a reversible type IV isotherm, which is a primary characteristic of mesoporous materials. γ-Fe2O3-LSB had a specific surface area (SBET = 135.30 m2/g) which is greater than that of LSB (SBET = 11.54 m2/g). γ-Fe2O3-LSB exhibits a saturation magnetization value (Ms) of 3.72 emu/g which shows its superparamagnetic nature. The batch adsorption process was performed to analyze the adsorptive removal of MB dye using γ-Fe2O3-LSB. The adsorption efficiency of γ-Fe2O3-LSB for MB was analyzed by varying parameters like the initial concentration of adsorbate (MB), γ-Fe2O3-LSB dose, pH effect, contact time, and temperature. Adsorption isotherm, kinetic, and thermodynamics were also studied after optimizing the protocol. The non-linear Langmuir model fitted the best to explain the adsorption isotherm mechanism and resulting adsorption capacity ( q e =54.55 mg/g). The thermodynamics study showed the spontaneous and endothermic nature, and pseudo-second-order rate kinetics was followed during the adsorption process. Regeneration study showed that γ-Fe2O3-LSB can be used up to four cycles. In laboratory setup, the cost of γ-Fe2O3-LSB synthesis comes out to be 162.75 INR/kg which is low as compared to commercially available adsorbents. The results obtained suggest that magnetic Lagenaria siceraria biochar, which is economical and efficient, can be used as a potential biochar material for industrial applications in the treatment of wastewater. [ABSTRACT FROM AUTHOR]

The cross sections for 58 Co(n,xp) reactions have been determined in the equivalent neutron energy range of 11.7–16.8 MeV by employing the surrogate reaction ratio method and using the cross-section values for the reference reaction 60 Ni(n,xp) from the literature. The transfer reactions 57 Fe( 6 Li, α ) at E lab = 37 MeV and 59 Co( 6 Li, α ) at E lab = 33 MeV, are used to populate compound nuclei 59 Co ∗ (surrogate of n+ 58 Co) and 61 Ni ∗ (surrogate of n+ 60 Ni), respectively, at similar excitation energies. The evaporated protons at backward angles measured in coincidence with the projectile-like fragment alpha provide the proton decay probabilities of the compound nuclei. The cross sections estimated using the nuclear-reactions-model code talys-1.96 are consistent with the experimental 58 Co(n,xp) data for the entire neutron energy range. However, the predictions of the evaluated data libraries endf/b-viii, jeff-3.3, jendl-5, rosfond-2010 and tendl-2019 overestimate the present experimental data, indicating the necessity to improve the model parameters of the data libraries for this reaction. [ABSTRACT FROM AUTHOR]

This paper investigates the enhanced cooling performance of a hybrid microchannel heat sink, consists of the microchannel, nozzle and pillars, in terms of various hydrothermal characteristic parameters. Geometric and flow variables such as jet inclination angle (30°–90°), Reynolds number (200–600) and nozzle diameter (in increasing/decreasing order) are considered for the analysis. Parameters related to both the first and second laws of thermodynamics are computed numerically using commercial software ANSYS FLUENT. The decreasing nozzle diameter layout provided the lowest value of the maximum wall temperature as well as a moderate hike in the pressure drop with respect to other cases. Similarly, a smaller nozzle angle is more suitable for better cooling than the larger nozzle angles. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the non-existence of isolated nodes in secure wireless sensor networks under full visibility condition. Here, we consider a sensor network with n sensor nodes distributed uniformly over a compact space $$C \subset {\mathbb {R}}^2$$ . We establish a threshold for the proportion of key ring and key pool size; above this threshold isolated nodes disappear from the network almost surely. We derive that for key pool of size $$cn\log \,n$$ and key ring of size $$c\log \,n$$ (of an arbitrary node) and $$c>2$$ there will be no isolated nodes in the network almost surely. [ABSTRACT FROM AUTHOR]

The effect of small concentrations of zirconium on the cyclic oxidation behavior of Fe-15Cr-4Al was investigated at 1300°C. The zirconium concentrations studied were 0.2, 0.55, and 1 wt.%. Each cycle consisted of a 1-hr isothermal period followed by 30-min cooling of the sample in air. Nodule formation was observed in higher zirconium-containing alloys, 0.55% and 1% zirconium, and the base alloy. The nodules formed at the corners and edges of the specimen and grew with increasing number of cycles. EDAX and line scans of cross section of oxidized samples demonstrated that the nodules were composed of iron oxides. Suggestions are given regarding the mode of nodule formation. Results show that additions of 0.2% zirconium and 1% yttrium to the base alloy suppress the nodule formation and provide the best resistance to cyclic oxidation. [ABSTRACT FROM AUTHOR]