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Water pollution and antimicrobial resistance (AMR) have become two global threats; 80% of diseases and 50% of child deaths are due to poor water quality. In this study, hydrothermal processing was employed to manufacture manganese oxide nanorods. Silver dopant was deposited on the surface of manganese oxide. XRD diffractogram confirmed the facile synthesis of Ag/Mn2O3 nanocomposite. XPS survey analysis demonstrated silver content of 9.43 atom %. Photocatalytic measurements demonstrated the outstanding efficiency of the Ag-Mn2O3 compared to virgin oxide particles under visible radiation. Degradation efficiencies Mn2O3 and Ag/Mn2O3 on methyl orange (MO) dye was found to be 53% and 85% under visible spectrum. Silver dopant was found to decrease the binding energy of valence electrons; this action could support electron–hole pair generation under visible spectrum and could promote catalytic performance. Ag/Mn2O3 NPs demonstrated most effective performance (95% removal efficiency) at pH 3; this could be ascribed to the electrostatic attraction between positively charged catalyst and the negatively charged MO. Ag/Mn2O3 demonstrated enhanced antibacterial activity against Gram-positive Staphylococcus aureus (S. aureus) (19 mm ZOI), and Gram-negative Escherichiacoli (E. coli) (22 mm ZOI) respectively; the developed nanocomposite demonstrated advanced anti-film activity with inhibition percentage of 95.5% against E. coli followed by 89.5% against S. aureus. [ABSTRACT FROM AUTHOR]

Background: Most cancers acquire numerous genetic changes in proto-oncogenes as well as tumor-suppressor genes. Cancer's early diagnosis remains a challenge. Recently, nonlinear polarization has revealed the potential as a promising tool for early cancer diagnosis. Laser-induced nonlinear polarization can offer a novel fingerprint signature. Methods: In this study, nonlinear polarization was adopted for the characterization of both DNA and RNA samples from healthy volunteers. Total DNA and RNA were illuminated with a 656-nm LED source, and the resonance frequencies (scattered and re-emitted signals) were captured and recorded using a hyperspectral camera. Results: Changes in signal frequency as well as phase shift offered a potent means to differentiate DNA (control) from RNA (control). DNA (control) demonstrated characteristic resonance frequencies that differ from total RNA (control) at the 2nd, 3rd, 4th, and 5th harmonics. While DNA demonstrated a phase shift dominating at 0.88 GHz, RNA dominates at 0.106 GHz. The resonance spectral signature of RNA samples from people with hepatocellular carcinoma (HCC) was compared to that of RNA (control). RNA (HCC) demonstrated distinctive frequency signals at 0.014, 0.021, 0.032, and 0.072 GHz. These characteristics feature could facilitate early HCC diagnosis. While RNA (control) dominates at 0.014 and 0.072 MHz, RNA (HCC) dominates at 0.021 and 0.032. Conclusion: As far as we are aware, this is the initial investigation into the use of simple nonlinear polarization to generate spectral fingerprinting signatures of total DNA and RNA. Furthermore, RNA mutations due to HCC were identified via characteristic nonlinear spectral signature. [ABSTRACT FROM AUTHOR]

As ferric oxide is a well-known catalyst, aluminum can act as a high energy dense material. Ferric oxide/aluminum can experience nanothermite reaction with novel synergistic characteristics. On the other hand, nitrocellulose (NC) is the most energetic polymeric matrix. This study reports on the facile development of thermite-based NC nanocomposite. Ferric oxide nanoparticles (NPs) of 5 nm size and aluminum NPs of 80 nm size were dispersed in acetone. Colloidal ferric oxide/aluminum NPs were integrated into NC matrix via anti-solvent technique. Nanothermite particles offered an increase in NC decomposition enthalpy by 38.59% using differential scanning calorimetry (DSC). The apparent activation energy of NC was reduced by 14% and 14.5%, using Friedman and OZAW models, respectively. Activation energy at different conversion extent was evaluated, and decomposition mechanisms have been suggested to be heterogeneous solid phase reaction. The developed NC nanocomposite is considered bespoke material for first-fire ignition systems; where molten solid particle and high decomposition enthalpy are highly appreciated. [ABSTRACT FROM AUTHOR]

Mn-doped Co3O4 nanoparticles of 15 nm were developed via solvothermal synthesis. Mn@Co3O4 microspheres were developed via controlled annealing treatment at 600 °C. Mn@Co3O4 microspheres demonstrated an average diameter of 5.5 µm, with specific area (BET) of 73.7 m2 g−1. The pore diameter was centered at 13.1 nm, and the mean pore size was 16 nm; porous structure could secure extensive interfacial surface area. Mn@Co3O4 microspheres were integrated into ammonium perchlorate (AP) matrix. The catalytic activity of Mn@Co3O4 on AP decomposition was assessed via DSC and TGA/DTG. Whereas Mn@Co3O4/AP nanocomposite demonstrated decomposition enthalpy of 1560 J g−1, pure AP demonstrated 836 J g−1. While Mn@Co3O4/AP nanocomposite demonstrated one decomposition temperature at 310 °C,pure AP exposed two decomposition stages at 298 °C, and 453 °C. Decomposition kinetics was investigated via isoconversional (model free) and model fitting. Kissinger, Kissinger–Akahira–Sunose (KAS), integral isoconversional method of Ozawa, Flyn and Wall (FWO), and differential isoconversional method of Friedman. Mn@Co3O4/AP demonstrated apparent activation energy of 149.7 ± 2.54 kJ mol−1 compared with 173.16 ± 1.95 kJ mol−1 for pure AP. While AP demonstrated sophisticated decomposition models starting with F3 followed by A2, Mn@Co3O4/AP nanocomposite demonstrated A3 decomposition model. Mn@Co3O4 can expose active surface sites; surface oxygen could act as electron donor to electron deficient perchlorate group. Furthermore, Mn@Co3O4/AP could act as adsorbent of released NH3 gas with efficient combustion. This study shaded the light on Mn@Co3O4 as potential catalyst for AP decomposition. [ABSTRACT FROM AUTHOR]

Manganese oxide with active surface sites can experience superior catalytic activity. MnO2 nanoparticles, of 11.4 nm particle size, were developed. Nitrocellulose (NC) was adopted as an energetic binder. Colloidal MnO2/Al nanothermite particles were integrated into the NC matrix via the co-precipitation technique. Nanothermite particles experienced an increase in NC decomposition enthalpy by 150% as well as enhanced reaction propagation index by 261%. A kinetic study demonstrated that nanothermite particles experienced a drastic decrease in NC activation energy by – 42 and – 40 kJ · mol−1 using Kissinger and KAS models, respectively. Novel energetic nanocomposite with superior combustion enthalpy, propagation index, and the activation energy was developed. [ABSTRACT FROM AUTHOR]

Ammonium perchlorate (AP)/HMX co-crystal with dual catalytic effect was developed. Proper integration of AP particles into the HMX matrix was verified with the evolution of novel crystalline structure. AP/HMX co-crystal demonstrated an increase in HMX decomposition enthalpy by + 57.5%. HMX demonstrated activation energy of 343.2 and 354.4 kJ/mol using Kissinger and KAS models, respectively. AP/HMX co-crystal demonstrated a decrease in HMX activation energy by −75% and −76%, correspondingly. AP could act as an active point with the release of reactive gases that could boost HMX decomposition. HMX experienced a catalytic effect with the disappearance of AP endothermic phase transition. [ABSTRACT FROM AUTHOR]

HMX is one of the most powerful energetic materials; however, HMX experience low sensitivity and high activation energy. Whereas ferric oxide particles can act as catalyst for HMX decomposition with change in its decomposition kinetics from C-N bond cleavage to hydrogen atom abstraction; ferric oxide can induce vigorous thermite reaction with aluminum particles. Consequently, thermite particles can catalyze HMX decomposition, and enhance its decomposition enthalpy. This study reports on the fabrication and of ferric oxide nanoparticles of 5 nm particle size. Ferric oxide NPs and aluminum nanoplates of 100 nm were effectively integrated into HMX via co-precipitation technique. Elemental mapping was performed using EDAX detector; uniform dispersion of nanothermite particles was confirmed. Nanothermite particles experienced enhanced HMX decomposition enthalpy by 53%, with decrease in decomposition temperature by 13°C. The impact of nanothermite particles on HMX kinetic decomposition was evaluated using two different analysis models including differential isoconversional method of model-free Friedman analysis, and integral isoconversional method of Ozawa. Thermite nanoparticles demonstrated drastic decrease in HMX activation energy by 24 and 30% using Friedman and Ozawa models, respectively. The developed colloidal nanothermite particles demonstrated superior catalytic effect with enhanced decomposition enthalpy. [ABSTRACT FROM AUTHOR]