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Chemical doping and coating have been considered as efficient semiconductor physics strategies to modulate the physical, chemical, and biological properties of materials for the required applications. In this study, cetyltrimethylammonium bromide (CTAB) stabilizer-capped nickel-doped cupric oxide (NixCu1−xO) nanoparticles (NPs) with different doping concentrations (0.0 ≤ x ≤ 0.05) were synthesized via a one-step rapid and low-cost solvothermal synthesis route. The as-synthesized CTAB-capped NixCu1−xO NPs have been sightseen for their structural/morphological, optical/dielectric, and antimicrobial properties using XRD/SEM/TEM, FT-IR/UV–visible/Impedance spectroscopies, and Agar well diffusion method, respectively. Relevant results show enhanced optical, dielectric and antimicrobial properties with Ni doping due to the smaller size effect. Importantly, in vitro examination, the antimicrobial activity of the grown NPs was evaluated against four microbial species, exhibits that the CTAB-capped Ni-doped CuO NPs possess a command antimicrobial toxicity to Staphylococcus aureus (25923-ATCC), Klebsiella pneumoniae (700603-ATCC), and Escherichia coli (25922-ATCC) and an intermediate performance towards Candida albicans (24433-ATCC). The minimum inhibitory concentration (MIC) assay for the obtained CTAB-Ni0.05Cu0.95O sample upon S. aureus or K. pneumoniae pathogens reaches extremely as low as 5 μg ml−1 for all reported CuO NPs. The improved dose-dependent antimicrobial effect has been found to be strongly dependent on the particle size, surface morphology, elemental compositions, and surface bio-functionality of the catalytic nanomaterials. Additionally, Ni-dopant, CTAB-stabilizer, and binding of Cu+/Cu2+ ions with respiratory enzymes collectively produce an excess amount of reactive oxygen species (ROS) in the bacterial culture medium, which determines a predominant antibacterial mechanism for bacterial cells damage. Overall, these inorganic (NixCu1−xO) NPs with antimicrobial cationic surfactant (CTAB) have advantages to use as a functionalized disinfection nanoagent to control the microbial infections in the healthcare sector together with various electronic and photonic medical diagnoses.

Recently, due to the increasing concentration of carbon dioxide emissions in the atmosphere, the global environment has changed dramatically. As a result, climate change, global warming, and environmental degradation-like issues have been raised. Presumably, human beings, as well as the agricultural ecosystem, become most vulnerable to these issues. In this context, the study focuses on the nexus between Indian's agricultural ecosystem and carbon dioxide emission. For the purpose of this study, annual time series data over the time span from 1990 to 2014 was used. The modern techniques, for instance, Johansen, ARDL, and Granger causality, were employed. The Johansen test and ARDL model suggest that carbon dioxide emissions and agricultural ecosystems are co-integrated. In the short run, the ARDL model suggests that a 1% increase in biomass-burned crop residues, total pesticides, and stock of livestock would increase carbon dioxide emissions by 0.26, 0.3, and 6.58% respectively. The residual diagnostics tests suggest that the ARDL model is stable, reliable, and credible in the present form. The results of the granger causality show that a unidirectional causality was found between carbon dioxide and total heads of livestock, all animal manure applied to the soil, agricultural technology, and total pesticide used in the agricultural sector. In contrast, bidirectional causality was found between the production of biomass-burned crop residues and carbon dioxide emission. Therefore, it is suggested that the government should take preemptive action to reduce the risk of environmental pollution and degradation through synchronized strategies particularly by reducing the amount of biomass-burned crop residues and usage of total pesticides in the country.

Direct fabrication of titanium (Ti) and niobium (Nb) alloys by direct magnesiothermic reduction from the respective initial metal oxides and complex oxides has been studied. TiO2, Nb2O5, and complex TiNb2O7 oxides were used as raw materials with Mg used as a reductant. To ensure a high chemical potential of the reactants to drive the spontaneous magnesiothermic reduction of the oxide mixtures, excess Mg five times higher than the required stoichiometric molar ratio was added. Samples were heated in a glove box under recycled and purified Ar atmosphere at 1073 K (800 °C) for 10 h. After the reduction of TiO2, intermediate oxide phases of Ti6O could still be observed, but reduction of Nb2O5 and TiNb2O7 showed metallic Nb and Ti-Nb to be present with negligible oxides according to the scanning electron microscope-energy dispersive spectroscopy and x ray diffraction analysis. This indicated that direct fabrication of Ti-Nb alloys through a complex TiNb2O7 oxide is possible and can be more efficient than alloying pure metallic elements of Ti and Nb.

In this paper, we introduce a class of Suzuki-type contractive multivalued mappings and establish the existence of fixed points of such mappings in the setup of b-metric spaces. Some examples are presented to support the results proved herein. An estimate of Hausdorff distance between the fixed point sets of two Suzuki-type contractive multivalued mappings is obtained. As an application of results thus obtained, existence and uniqueness of periodic solution of delay differential equations are shown.

The aim of this paper is to introduce a class of generalized Suzuki type \( (\alpha _{*},\psi _{\varphi })\)-contractive multivalued operators and to prove the existence of fixed point and common fixed point of such operators in the setup of b-metric spaces. Some examples are presented to support the results proved herein. Our results generalize and extend various results in the existing literature. An estimate of Hausdorff distance between the fixed point sets of two generalized Suzuki type \((\alpha _{*},\psi _{\varphi })\)-contractive multivalued operators is obtained. We further investigate the Ulam–Hyers stability of fixed point problem of operators considered herein in the framework of b-metric spaces.

The aim of this paper is to introduce a new type of generalized multivalued contraction mappings and to present some results regarding fixed points of new class of multivalued contractions. As applications we obtain some basic results in fixed point theory like characterization of metric completeness, data dependence of fixed points and homotopy result. We prove the existence and uniqueness of bounded solution of functional equation arising in dynamic programming. Our results generalize, extend and unify various comparable results in the existing literature.

In this paper, we prove a coupled fixed point theorem for a multivalued fuzzy contraction mapping in complete Hausdorff fuzzy metric spaces. As an application of the first theorem, a coupled coincidence and coupled common fixed point theorem has been proved for a hybrid pair of multivalued and single-valued mappings. It is worth mentioning that to find coupled coincidence points, we do not employ the condition of continuity of any mapping involved therein. Also, coupled coincidence points are obtained without exploiting any type of commutativity condition. Our results extend, improve, and unify some well-known results in the literature. MSC:47H10, 47H04, 47H07.