Reliable assessment of the long-term structural integrity of solid rocket motors requires quantitative understanding of the stress- and temperature-dependent viscoelastic response of composite propellants subjected to sustained thermo-mechanical loading. In highly filled energetic formulations, minor variations in formulation architecture and energetic filler chemistry (e.g., HMX and RDX) can induce disproportionate changes in creep–recovery behavior, thereby influencing dimensional stability, stress redistribution, and service life. In this study, the creep–recovery response of three high-energetic composite propellants (C-I, C-II, and C-III) is systematically investigated using dynamic mechanical analysis over a broad stress range (0.1–3 MPa) and temperature domain (−20°C to 55°C), representing one of the first comprehensive evaluations encompassing both HMX- and RDX-based fillers under combined thermo-mechanical conditions. Viscoelastic constitutive modeling reveals that the Burgers model provides the most robust and physically interpretable representation of the strain–time response, resolving instantaneous elastic deformation, time-dependent viscoelastic creep, and irreversible viscous strain with high fidelity. All formulations exhibit primary and secondary creep without onset of tertiary creep within the investigated regime. Among the compositions, C-III demonstrates the highest resistance to time-dependent deformation and superior load-bearing capacity, whereas C-II shows elevated compliance and accelerated strain accumulation at increased stress and temperature, with C-I exhibiting intermediate behavior. Post-DMA scanning electron microscopy corroborates these rheological trends, revealing formulation-dependent interfacial debonding, void nucleation, cavitation, and matrix plasticization, thereby establishing a direct structure–property correlation governing the sustained-load viscoelastic stability of high-energetic composite propellants.

This study herewith examines the impact of hydantoin resin (HR) as a bonding agent (BA) on the properties of four formulations of highly plasticized composite propellants (CP) with a nitrate ester-based novel active binder system. The research focuses on its effect on rheological, mechanical, thermal, sensitivity and ballistic characteristics of propellants. Reduced de-wetting and improved cohesivity between binder and filler exhibit paramount dependency on optimization of BA content. Results indicate that increasing HR content significantly improves tensile strength, modulus, and thermal stability, while slightly reducing burn rate and

A comparative thermomechanical study of nitrile butadiene rubber (NBR)-based high-energy composite propellants was conducted to clarify formulation-dependent deformation and damage mechanisms. Two compositions, Type I (78 wt.% solids) and Type II (79 wt.% solids), were examined through uniaxial tensile testing (5-1000 mm & centerdot;min-& sup1;) at -20, 27, and 55 degrees C, supported by dynamic mechanical analysis (-80 to 80 degrees C). Stress-strain behavior exhibited three regimes linear elasticity, de-wetting, and strain hardening governed by binder continuity and filler packing. Type I, with higher binder content, demonstrated superior ductility, sustained strain hardening, broader failure boundary envelope, and matrix-dominated damage across loading conditions. Type II showed increased modulus, greater strain-rate sensitivity, and interface-controlled failure marked by accelerated de-bonding. Time-temperature superposition and cumulative damage modeling quantified rheo-kinetic sensitivity and durability limits. The results define formulation-specific thermomechanical operating envelopes, highlighting the trade-off between stiffness and damage tolerance critical for propellant structural reliability.

Over the years, Combustion Instability in solid rocket motors has been an unsolved problem. Combustion Instability can be referred to as an oscillatory amplification to high-pressure levels which causes damage to the motor, levels down the engine efficiency and destroys the burner. This is due to the interaction between the acoustic field and unsteady heat release. One of the simplest methods to acquire combustion instability-related data is the T-Burner setup which does not require a full-scale motor. A T-Burner primarily focuses on pressure-coupled responses which are usually longitudinal oscillations. This research reports experimental and numerical works on oscillatory pressure measurements using T-Burner which is comprised of a few test firings with various lengths and diameters. Double-base propellants are tested in the setup to measure the acoustic losses using pressure sensors at the ends. Further using MATLAB software, important variables are characterised such as the decay constant and growth constant which further calculates admittance and response function.

Nanotechnology has significantly improved drug delivery and targeting in central nervous system diseases and neurodegenerative diseases. Intranasal drug delivery has emerged as a promising approach for enhancing therapeutic outcomes by leveraging the unique anatomical and physiological characteristics of the nasal cavity. This route offers several advantages, including rapid absorption, bypassing the blood-brain barrier for central nervous system targeting, and improved patient compliance. The highly vascularized nasal mucosa facilitates efficient systemic drug absorption, making it an attractive option for both local and systemic treatments. This article explores the principles of intranasal drug delivery, the influence of nasal anatomy on drug bioavailability, and advancements in formulation strategies to optimize efficacy. Additionally, it addresses current challenges, including mucociliary clearance and enzymatic degradation, as well as innovative solutions designed to enhance drug stability and absorption. Understanding the interplay between nasal anatomy and drug delivery mechanisms can pave the way for novel therapeutic interventions and enhance the effectiveness of intranasal medications in various clinical applications. It also highlights challenges in the nasal delivery of therapeutics.

Efforts to catalytically accelerate the thermal decomposition of ammonium perchlorate (AP) in hydroxylterminated polybutadiene (HTPB)-based binder are cardinal for improving combustion and composite propellant ballistics. This study investigates rare earth sesquioxides (RES) - Dysprosium oxide (Dy2O3) and Erbium oxide (Er2O3) with partially filled f-orbitals as potential burn rate modifiers (BRM), owing to their electron transfer capabilities. A preliminary non-isothermal DSC study with 1 % RES loading shows a significant reduction in activation energy-61 % for Dy2O3 and 56 % for Er2O3-highlighting their catalytic efficacy. FTIR and XPS analyses confirm modifications in the chemical environment of AP in presence of RES. High-resolution spectra (O 1s, N 1s, Cl 2p) exhibit reduced binding energies and increased intensities. RES induces d-character in O 1s and Cl 2p orbitals, shifting hybridization from sp3 to sp2d. This enhances electron delocalization, accelerates Cl-O bond cleavage, and facilitates perchlorate reduction (Cl7+ -> Cl5+ -> Cl3+), corroborating an electron-transfer-based decomposition mechanism. Kinetic studies using isothermal DSC and model-fitting approach reveal a shift in AP decomposition mechanisms across three stages: low (Power law -> Avrami-Erofeev), intermediate (3D Diffusion -> Prout-Tompkins), and high (Avrami-Erofeev -> Contracting Cylinder) with RES. These findings underline the catalytic role of RES via lanthanide contraction and redox cycling (L1.5 <-> L2) which promote oxygen vacancy formation and enhance decomposition. A combined DFT and kMC simulation captures the thermal dependence of the evolving decomposition and redox behaviour. Overall, Dy2O3 and Er2O3 exhibit strong potential as BRMs, with ability to effectuate burn rates and specific impulse modulation in AP-HTPB propellants.

Nowadays, nanotechnology is extensively employed in the medical profession. In this study, we used the aqueous extract of the bark of Mitragyna parvifolia to synthesize silver nanoparticles (AgNPs) by microwave-assisted green synthesis. The synthesis of AgNPs was confirmed by visual color change to brown color and characteristic surface plasmon resonance peak at 432 nm. The hydrodynamic diameter of the AgNPs was 171.81 nm having a zeta potential of −24.14 mV; Fourier Transmission Infrared Spectroscopy confirmed the presence of different functional groups on the NP surface; Scanning Electron Microscope and High-Resolution Transmission Electron Microscopy indicated predominantly circular shape of nanoparticle; Selected Area Electron Diffraction and X-ray Diffraction analyses determined the crystalline structure of AgNPs. Energy-Dispersive X-ray indicated the elemental composition and formation of AgNPs. The AgNPs were screened at different concentrations for antioxidant activity, antimicrobial, and anticancer potential in breast cancer cells (MCF-7 and MDA-MB-231). The AgNPs exhibited remarkable antioxidant, antimicrobial, and anticancer activities. The sedative and antinociceptive activities were also tested on Swiss albino mice, which showed mild sedative and very potent antinociceptive activity. However, detailed mechanistic studies are warranted in the future for clinical application of the AgNPs as a biologically active agent as well as a carrier for drug delivery.

Colon is attracting interest as a site where poorly absorbed drug molecule may have an improved bioavailability.Additionally, the colon has a longer retention time and appears highly responsive to agents that enhance the absorption of poorly absorbed drugs.: The main aim of the present research was to develop and evaluate various matrix Objective tablet formulations of naproxen with different polymers.: Naproxen tablets formulation was Material and methods prepared for colon specific controlled release using combination of various polymer types (combination of EL100 and ES100), and (combination of EC with EL100 and ES100).Prepared tablets were characterized by physicochemical properties like weight variation, thickness, crushing strength, friability and drug content uniformity.In vitro release and kinetic studies were performed.In the present study, three formulations; viz., IEL15ES10, Results and conclusion: IEL10ES15 and IEL20EC5; were selected because they had shown good similarity with the theoretical target release profile in vitro as shown by their similarity factor f that was greater than 50 and dissimilarity factor f that was less than 2 115.The drug release profile from most of the selected formulations in simulated GI fluid (without enzymes) was characterized by an initial lag time period of 4-6 h with low drug release followed by controlled release phase in phosphate buffer media for about 14-16 h.Therefore, these formulations have the potential for pH and time dependent delivery to the colon.

Orally disintegrating tablets (ODT) disintegrate quickly with saliva when administered into the oral cavity and taken without water or chewed. ODT are easy to take for children and the elderly, who may experience difficultly in taking ordinary oral preparations such as tablets, capsules, and powders. The ODT threes substantial benefits for the patient (or elder) who cannot swallow (Dysphagia), or who is not permitted water intake due to disease. The reason of the current research was to prepare taste masking oral disintegrating tablets of poorly soluble lornoxicam (LXM) by direct compression technique using Kyron T-114 (cation exchange resin) as a taste masking agent. With in various ratios the Drug-resin of 1:4 was established to present best taste masking. The superdisintegrants used in formulation are croscarmellose sodium and cross povidone. Among these croscarmellose sodium demonstrated superior drug release. The tablets were evaluated for friability, weight variation, wetting time, hardness, disintegration time and uniformity of content. Optimized formulations were evaluated for in vitro dissolution test. Amongst all the formulations F-6 was found to be most successful tablets prepared by this technique had disintegration time of 30sec and % CDR 94.78 within 30min. Hence, this advance can be utilized for taste masking of bitter pharmaceutical ingredients leading to superior patient compliance. Keywords: Oral disintegration tablets, Lornoxicam, Kyron T-114, Superdisintegrants, Direct Compression.

The catalytic effect of copper tungsten oxide (CuWO4) was investigated on the thermal decomposition of ammonium perchlorate (AP) using differential scanning calorimetry. A lowering of the high-temperature decomposition peak temperature of AP was observed due to catalytic effect of copper tungsten oxide particles, now referred to as CTO in this paper henceforth. The kinetic parameters were evaluated using the Kissinger method. The decrease in the activation energy confirmed the catalytic activity of CTO. Further, CTO was evaluated in a standard composite propellant formulation having 86 % solid loading. Propellant performance and processing parameters such as the end of mix (EOM) viscosity, density, burning rate, pressure exponent (n-value), etc. were measured for standard as well as a composition containing 1 % CTO. The results revealed that at 1 % level CTO causes more than 36 % increase in propellant burning rate compared to the standard propellant composition at 6.86 MPa pressure. The pressure exponent also increased to 0.48, whereas the standard composition was having its value of 0.41.

Energetic materials (EMs) are a group of distinctive materials that release an enormous amount of amassed chemical energy in a short time when incited by external mechanical or thermal factors. They comprise of propellants, explosives, and pyrotechnics. Unlike conventional micro-energetic materials, nano energetic materials (nEMs), due to their smaller particle size ranging from 1-100 nm, exhibit higher specific surface area (similar to 10-50 m(2) g(-1)), reduced ignition temperatures from 2350 Kto approx.1000 Kfor particle size from 100 mu m to 100 nmrespectively, higher energy densities (up to 50 MJ kg(-1)), burning rates similar to 30.48 mm s(-1) at 6.894 kPa with specific impulses up to 542 s (5320 ms(-1)), low impact sensitivity (<4-35 J). Such exceptional properties of nano energetic composites, i.e., thermites (a combination of metal-fuel/metal oxide particles), find applications, namely in, munitions, pyrotechnics, energetic micro-electromechanical system (MEMS) chips. This review provides valuable insight into the synthesis methods of nano energetic composite systems (e.g., Al/CuO, Al/KMnO4, Al/Fe2O3, Al/SnO2, Silicon-based systems), their characteristic properties, behavior under certain conditions and applications. Furthermore, the review converses about the advancements made in the last few decades by many researchers, along with the technological gaps that need to be addressed for futuristic applications.

In the present paper a double funnel port grain configuration is studied in detail. The neutrality of the grain configuration is compared with the neutrality of a single funnel port grain configuration. After optimization of double funnel port grain dimensions to achieve maximum neutrality, the predicted pressure–time profile of realized grain is compared with the achieved pressure-time profile from rocket motor static testing. A close match was obtained between the two profiles. Thus, double funnel port grain configuration is established which can be utilized for estimating burning rate of propellant compositions at any desired pressure with good neutrality.

In the present work, various propellant compositions were prepared by incorporating strontium ferrite (SrFe12O19) in an ammonium perchlorate (AP), aluminium powder and hydroxyl-teminated polybutadiene (HTPB) based standard composite propellant. The compositions were then studied by assessing the effect of the SrFer(12)O(19) content on the propellant slurry viscosity, and the mechanical and ballistic properties. The results showed that as the percentage of SrFe12O19 in the propellant was increased, the end of mix (EOM) slurry viscosity, tensile strength and E-modulus increased, while the elongation decreased. The ballistic properties data revealed that the burning rate of the propellant composition containing 1.0% SrFe12O19 was enhanced by around 15% (at 6.86 MPa) compared to the standard composition burning rate.

In the present study, nano and micron-sized barium titanate (BaTiO3) were characterized and evaluated in HTPB/AP/Al composite propellant. Different compositions were prepared by incorporating BaTiO3 from 0.5 % to 2 % in a standard composition. The BaTiO3 reduces thermal decomposition temperature of ammonium perchlorate and also of standard composition. Other propellant processing and performance parameters like viscosity, mechanical and ballistic properties were also measured. The ballistic properties results revealed that there was more than 22 % and 12 % (at 6.86 MPa) enhancement in burning rate with 2 % nano and micro- BaTiO3, respectively.

In a quest of search for a new burning rate modifier for composite propellant, strontium titanate（SrTiO 3 ）,a perovskite oxide has been chosen for evaluation in a composite propellant formulation based on its other catalytic applications. Initially, SrTiO 3 was characterized for particle size, morphology and material/phase identification（using XRD）. By varying SrTiO 3 content in a standard composite propellant, different compositions were prepared and their performance and processing parameters like the end of mix（EOM） viscosity, mechanical properties, density, burning rate, pressure exponent（n-value）, etc. were measured. The results reveal that 2% SrTiO 3 causes more than 12% enhancement in propellant burning rate（at 70 ksc pressure） in comparison to the standard propellant composition. The pressure exponent also increases to 0.46, whereas the standard composition was having its value as 0.35.

Various propellant compositions were prepared incorporating fully characterized nano-sized manganese dioxide, from 0.25 wt.% to 1.0 wt.%, in HTPB/AP/Al-based composite propellant formulations having 86 wt.% of solid loading, and its effects on the viscosity build-up, thermal, mechanical and ballistic properties were studied. The findings revealed that on increasing the percentage of nano-MnO2 in the composition, there was an increase in the end of mix viscosity, the modulus and tensile strength, while the elongation decreased accordingly. The data on the thermal properties revealed a reduction in the decomposition temperature of ammonium perchlorate (AP) as well as of the formulations based on it. The data on the ballistic properties revealed that there is an enhancement in the burning rate from 6.11 mm/s (reference composition) to 7.54 mm/s at 6.86 MPa (a 23% enhancement in the burning rate) and an increase in the pressure exponent from 0.35 (reference composition) to 0.42 with 1.0 wt.% nano-MnO2.

Different propellant compositions were prepared by incorporating nano-sized cobalt oxide from 0.25% to 1% in HTPB/AP/Al-based composite propellant formulations with 86% solid loading. The effects on viscosity build-up, thermal, mechanical and ballistic properties were studied. The findings revealed that by increasing the percentage of nano-Co3O4 in the composition, the end of mix viscosity, the modulus and the tensile strength increased, whereas the elongation decreased accordingly. The thermal property data envisaged a reduction in the decomposition temperature of ammonium perchlorate (AP) as well as formulations based on AP. The ballistic property data revealed an enhanced burning rate from 6.11mms(-1) (reference composition) to 8.99mms(-1) at 6.86MPa and a marginal increase in pressure exponent from 0.35 (reference composition) to 0.42 with 1% nano-cobalt oxide.

The incorporation of nanoaluminum in an 86% solid composite propellant formulation poses processing problems when following conventional methods. Therefore, to accommodate an optimum percentage of nanoaluminum in such formulations, a new bicurative system was introduced. Summarizing in the present study, a bicurative system consisting of toluene diisocyanate and isophorone diisocyanate was chosen to enable incorporation of 18% nanoaluminum powder (93 nm) in place of 18% micrometer-sized Aluminum powder. The developed compositions were studied in detail for their mechanical, thermal, sensitivity, and ballistic properties. The mechanical properties data, such as tensile strength, E modulus, and percentage elongation, are almost on par with the values obtained with micrometer-sized aluminum powder using a developed bicurative system. The results of thermal properties reveal that, as the percentage of nanoaluminum increases in the composition, the onset decomposition temperature decreases. The impact and friction sensitivity data indicate that the sensitivity of the propellant formulation increases in comparison to micrometer-sized aluminum powder propellant. The ballistic properties, such as burning rate and ballistic evaluation motor data, reveal that there is more than a 110% increase in burning rate and a gain in specific impulse on the order of 6 s in comparison with propellants using micrometer-sized aluminum powder.

Context: In recent years, nanotechnology-based delivery systems have gained interest to overcome the problems of restricted absorption of therapeutic agents from the nasal cavity, depending upon the physicochemical properties of the drug and physiological properties of the human nose.Objective: The well-tolerated and non-invasive nasal drug delivery when combined with the nanotechnology-based novel formulations and carriers, opens the way for the effective systemic and brain targeting delivery of various therapeutic agents. To accomplish competent drug delivery, it is imperative to recognize the interactions among the nanomaterials and the nasal biological environment, targeting cell-surface receptors, drug release, multiple drug administration, stability of therapeutic agents and molecular mechanisms of cell signaling involved in patho-biology of the disease under consideration.Methods: Quite a few systems have been successfully formulated using nanomaterials for intranasal (IN) delivery. Carbon nanotubes (CNTs), chitosan, polylactic-co-glycolic acid (PLGA) and PLGA-based nanosystems have also been studied in vitro and in vivo for the delivery of several therapeutic agents which shown promising concentrations in the brain after nasal administration.Results and conclusion: The use of nanomaterials including peptide-based nanotubes and nanogels (NGs) for vaccine delivery via nasal route is a new approach to control the disease progression. In this review, the recent developments in nanotechnology utilized for nasal drug delivery have been discussed.