trans‐Di­aqua­bis­(thio­semicarb­azido‐κ2N,S)­nickel(II) dimaleate dihydrate

In the title compound, [Ni(CH₅N₃S)₂(H₂O)₂](C₄H₃O₄)₂·2H₂O, the Ni atom lies on a center of symmetry and is coordinated by N and S atoms from two thio­semicarbazide ligands and the O atoms of two water mol­ecules in a distorted octahedral geometry. In the asymmetric unit, the three components are linked together by one O—H⋯O and two N—H⋯O hydrogen bonds. The packing is built from molecular ribbons parallel to the b direction, stabilized by intramolecular hydrogen bonds, and by one N—H⋯S and two N—H⋯O intermolecular hydrogen bonds. The ribbons are further connected into columns by N—H⋯O interactions and then into a three‐dimensional network by three O—H⋯O hydrogen bonds.     

Capacity maximizing in massive MIMO with linear precoding for SSF and LSF channel with perfect CSI

The capacity of a massive MIMO cellular network depends on user and antenna selection algorithms, and also on the acquisition of perfect Channel State Information (CSI). Low computational cost algorithms for user and antenna selection significantly may enhance the system capacity, as it would consume a smaller bandwidth out of the total bandwidth for downlink transmission. The objective of this paper is to maximize the system sum-rate capacity with efficient user and antenna selection algorithms and linear precoding. We consider in this paper, a slowly fading Rayleigh channel with perfect acquisition of CSI to explore the system sum-rate capacity of a massive MIMO network. For user selection, we apply three algorithms, namely Semi-orthogonal user selection (SUS), Descending Order of SNR-based User Scheduling (DOSUS), and Random User Selection (RUS) algorithm. In all the user selection algorithms, the selection of Base Station (BS) antenna is based on the maximum Signal-to-Noise Ratio (SNR) to the selected users. Hence users are characterized by having both Small Scale Fading (SSF) due to slowly fading Rayleigh channel and Large-Scale Fading (LSF) due to distances from the base station. Further, we use linear precoding techniques, such as Zero Forcing (ZF), Minimum Mean Square Error (MMSE), and Maximum Ratio Transmission (MRT) to reduce interferences, thereby improving average system sum-rate capacity. Results using SUS, DOSUS, and RUS user selection algorithms with ZF, MMSE, and MRT precoding techniques are compared. We also analyzed and compared the computational complexity of all the three user selection algorithms. The computational complexities of the three algorithms that we achieved in this paper are O(1) for RUS and DOSUS, and O(M²N) for SUS which are less than the other conventional user selection methods.     

The Flow of Blood-Based Hybrid Nanofluids with Couple Stresses by the Convergent and Divergent Channel for the Applications of Drug Delivery

This research work aims to scrutinize the mathematical model for the hybrid nanofluid flow in a converging and diverging channel. Titanium dioxide and silver TiO2 and Ag are considered as solid nanoparticles while blood is considered a base solvent. The couple-stress fluid model is essentially use to describe the blood flow. Therefore, the couple-stress term was used in the recent study with the existence of a magnetic field and a Darcy–Forchheiner porous medium. The heat absorption/omission and radiation terms were also included in the energy equation for the sustainability of drug delivery. An endeavor was made to link the recent study with the applications of drug delivery. It has already been revealed by the available literature that the combination of TiO2 with any other metal can destroy cancer cells more effectively than TiO2 separately. Both the walls are stretchable/shrinkable, whereas flow is caused by a source or sink with α as a converging/diverging parameter. Governing equations were altered into the system of non-linear coupled equations by using the similarity variables. The homotopy analysis method (HAM) was applied to obtain the preferred solution. The influences of the modeled parameters have been calculated and displayed. The confrontation of wall shear stress and hybrid nanofluid flow increased as the couple stress parameter rose, which indicates an improvement in the stability of the base fluid (blood). The percentage (%) increase in the heat transfer rate with the variation of nanoparticle volume fraction was also calculated numerically and discussed theoretically.     

Piezoelectric Nylon-11 Fibers for Electronic Textiles,Energy Harvesting and Sensing

Electronic textiles and functional fabrics are among the key constituents envisioned for wearable electronics applications. For e-textiles, the challenge is to process materials of desired electronic properties such as piezoelectricity into fibers to be integrated as wefts or wraps in the fabrics. Nylons, first introduced in the 1940s for stockings, are among the most widely used synthetic fibers in textiles. However, realization of nylon-based e-textiles has remained elusive due to the difficulty of achieving the piezoelectric phase in the nylon fibers. Here, piezoelectric nylon-11 fibers are demonstrated and it is shown that the resulting fibers are viable for applications in energy harvesting from low frequency mechanical vibrations and in motion sensors. A simulation study is presented that elucidates on the sensitivity of the nylon-11 fibers toward external mechanical stimuli. Moreover, a strategy is proposed and validated to significantly boost the electrical performance of the fibers. Since a large fraction of the textile industry is based on nylon fibers, the demonstration of piezoelectric nylon fibers will be a major step toward realization of electronic textiles for applications in apparels, health monitoring, sportswear, and portable energy generation.     

Computing the single-link performance measurement for elastic optical OFDM

Elastic optical networks based on orthogonal frequency-division multiplexing (OFDM) have emerged as the preferred technology for future optical networks because of their good spectral efficiency and flexibility. In OFDM optical networks, multiple subcarriers can be allocated to accommodate both subwavelength and superwavelength traffic. In this work, we developed an algorithm based on the superposition concept in electrical networks using the Kaufman/Delbrouck recursion model to accurately compute the revenue loss in the OFDM-based single link. The algorithm is applicable when there are many call types requesting diverse numbers of contiguous subcarriers offered to a link with numerous subcarriers.     

Green Synthesis of Nickel Oxide Nanoparticles from Berberis balochistanica Stem for Investigating Bioactivities

Green synthesis of nanomaterials is advancing due to its ease of synthesis, inexpensiveness, nontoxicity and renewability. In the present study, an eco-friendly biogenic method was developed for the green synthesis of nickel oxide nanoparticles (NiONPs) using phytochemically rich Berberis balochistanica stem (BBS) extract. The BBS extract was rich in phenolics, flavonoids and berberine. These phytochemicals successfully reduced and stabilised the NiNO₃ (green) into NiONPs (greenish-gray). BBS-NiONPs were confirmed by using UV-visible spectroscopy (peak at 305 nm), X-ray diffraction (size of 31.44 nm), Fourier transform infrared spectroscopy (identified -OH group and Ni-O formation), energy dispersive spectroscopy (showed specified elemental nature) and scanning electron microscopy (showed rhombohedral agglomerated shape). BBS-NiONPs were exposed to multiple in vitro bioactivities to ascertain their beneficial biological applications. They exhibited strong antioxidant activities: total antioxidant capacity (64.77%) and 2, 2-diphenyl-1-picrylhydrazyl (71.48%); and cytotoxic potential: Brine shrimp cytotoxicity assay with IC₅₀ (10.40 µg/mL). BBS-NiONPs restricted the bacterial and fungal pathogenic growths at 1000, 500 and 100 µg/mL. Additionally, BBS-NiONPs showed stimulatory efficacy by enhancing seed germination rate and seedling growth at 31.25 and 62.5 µg/mL. In aggregate, BBS extract has a potent antioxidant activity which makes the green biosynthesis of NiONPs easy, economical and safe. The biochemical potential of BBS-NiONPs can be useful in various biomedical and agricultural fields.