Rajiv Gandhi University (RGU) (formerly Arunachal University) is the oldest university in the Indian state of Arunachal Pradesh. It is located at Rono Hills in Doimukh town, about nine miles from the state capital, Itanagar. The foundation stone for the university was laid in 1984 by then-Prime Minister Indira Gandhi. The university was renamed as Rajiv Gandhi University in 2005 when UPA Chairperson Sonia Gandhi was on a visit to the state.
Convective boundary conditions act as a link between the fluid and its surroundings, altering wall temperatures and temperature gradients, which in turn directly influence the critical Rayleigh number and system stability. In this context, the novelty of the present study lies in investigating the convective instability of a bi-viscous Bingham fluid flowing through a horizontal porous channel with vertical throughflow, subject to convective thermal boundary conditions at both walls. After introducing appropriate non-dimensional scales, infinitesimal disturbances are superimposed on the basic steady-state flow, and linear stability analysis is performed to examine the resulting stability characteristics of the system. The corresponding eigenvalue problem associated with the neutral stability condition is numerically solved using the bvp4c solver in MATLAB. The results show that system stability increases monotonically as stronger external heating is applied at the bottom wall, irrespective of whether the external heating at the top wall increases or decreases. The system remains stable only when the heating at the bottom wall is dominated by stronger external heating at the top wall; otherwise, instability occurs. Furthermore, the study examines the onset of convection under two limiting boundary conditions: one boundary prescribed with a heat flux and the other maintained at an isothermal state. Finally, it is found that the onset of convection occurs earlier as the bi-viscous Bingham parameter increases for all considered boundary conditions.
Two-dimensional (2D) MoS2 and MoS2/graphene oxide (GO) nanocomposites were synthesized via a chemical bath deposition (CBD) method and systematically explored for visible light photodetection. Structural and microscopic characterizations confirmed the formation of hexagonal-phase MoS2 nanosheets and effective GO incorporation, accompanied by a reduction in crystallite size and an increase in lattice strain in the hybrid system. Optical absorption studies revealed a pronounced blue shift compared to bulk MoS2, with the optical bandgap increasing from 2.2 eV for pristine MoS2 to 2.5 eV for the MoS2/GO nanocomposite (1:2 ratio), indicating strong quantum confinement effects. Photoluminescence measurements showed substantial quenching upon GO incorporation, suggesting suppressed electron-hole recombination and enhanced interfacial charge separation. Planar photodetector devices fabricated using MoS2 and MoS2/GO exhibited distinct wavelength- and intensity-dependent photoresponse across the visible spectrum (492-621 nm). The MoS2/GO device consistently outperformed pristine MoS2, delivering significantly enhanced photocurrent, responsivity, detectivity, and external quantum efficiency. At an illumination intensity of 45,000 lux, the photocurrent increased from 0.05 & times; 10(-6) A for MoS2 to 7.70 & times; 10(-6) A for the MoS2/GO nanocomposite. Temperature-dependent transport measurements yielded activation energies of similar to 0.09 eV (MoS2) and similar to 0.08 eV (MoS2/GO), indicating facilitated charge transport in the hybrid structure. These results demonstrate that controlled GO incorporation is an effective strategy for optimizing the optical and photodetection performance of MoS2-based nanocomposites, making them promising candidates for scalable and cost-effective optoelectronic applications.
Three modifier oxides, MgO, ZnO, and CdO, were mixed with 1.0 mol % of Thulium-doped lead arsenate glasses and were synthesized by the usage of melt-quenching technique. XRD patterns clearly show the evidence that samples are amorphous and had been supported with the aid of using the lack of distinct peaks. Various functional physical parameters such as molar volume, oxygen packing density (OPD), Tm3+ ion concentration, mean Tm3+ ion separation, polaron radius are evaluated by using experimentally measured densities and refractive indices. The optical absorption spectra of PbO-MO (M = Mg, Zn, Cd)-As2O3:Tm2O3 glass system have been studied. Through the application of least square fitting analysis, the J-O phenomenological parameters (02, 04, 06) for the three glass systems have been calculated.
Let a(n) denote the number of integer partitions of a positive integer n wherein even parts appear in only one color (i.e. monochromatic) while the odd parts may appear in one of three colors (i.e. trichromatic). Hirschhorn and Sellers (2025) introduced a generalised version of a(n) and defined the partition function a(t)(n) wherein even parts appear in one colour and odd parts may occur with one of the t colours for any fixed positive integer t. They also proved some congruences modulo 7 for a(7j+1)(n) for any integer j >= 1. In this paper, we prove some new particular and infinite families of congruences for a(t)(n) by using q-series identities.
Flexible and electrochemical sensors are highly desirable for next-generation biomedical monitoring. Here, we present gold-modified MoSe2 nanowhiskers as a robust platform for non-enzymatic detection of Dopamine (DA). Controlled modification of MoSe2 with gold nanoparticles (0.5-4 wt.% Au) enhanced charge-transfer kinetics, while the nanowhisker morphology provided high surface area with abundant active sites for DA adsorption. Comprehensive characterization (XRD, Raman, FESEM, EDX, and XPS) confirmed the structural and electronic properties of the synthesized materials. Flexible electrodes fabricated on ITO-PET substrates were evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), where the 2 wt.% Au modified-MoSe2 electrode exhibited superior electrochemical performance. The sensor achieved two broad linear detection ranges (10 nm-0.4 mu m and 0.4-1.5 mu m) with high sensitivities of 1012.81 +/- 21.16 mu A.mu m -1.cm-2 (R2 approximate to 0.99) and 292.52 +/- 21.02 mu A.mu m -1.cm-2 (R2 approximate to 0.95), respectively. Further, the sensor demonstrated low limit of detection (LOD) of 14 nm and a limit of quantification (LOQ) of 47 nm. It also showed good response toward DA with minimal interference, excellent reproducibility, long-term stability, and mechanical flexibility under bending and temperature variations. These results highlight Au-modified MoSe2 nanowhiskers as a promising candidate for wearable and reliable electrochemical biosensing of neurotransmitters in early disease diagnostics.
