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Purpose: The axial vibration of short fiber reinforced composite nanorods is investigated for the first time in this paper. Short fibers are randomly distributed or aligned in composite nanorods. Methods: Nonlocal elasticity theory has been employed in the analysis. In addition to analytical solution of axial vibration problem of composite nanorods, finite element method is carried out to derive the natural frequencies for general boundary conditions. A two-noded rod finite element is used in the vibration problem. Results: The natural frequencies of composite nanorods predicted by the present analytical model are verified with the developed finite element solution for general boundary conditions. In addition, the natural frequencies are obtained for the viscously damped case of composite nanorods. Conclusion: The present study would be useful for the dynamic analyses of nanocomposite structures. [ABSTRACT FROM AUTHOR]

Bladder cancer is a common malignancy in the urinary system. Defects of drug molecules in bladder during treatment, such as passive diffusion, rapid clearance of periodic urination, poor adhesion and permeation abilities, lead to low delivery efficiency of conventional drugs and high recurrence rate of disease. In this study, we designed multi‐responsive mesoporous polydopamine (PDA) composite nanorods cooperating with nano‐enzyme and photosensitiser for intensive immunotherapy of bladder cancer. The strongly adhesive mesoporous PDA with wheat germ agglutinin on nanoparticles could specifically adhere to epithelial glycocalyx and made the nanoparticles aggregate in urinary pathways. Meanwhile, 2,3‐dimethylmaleic anhydride could be hydrolysed in acidic conditions of tumour microenvironment, giving it a positive charge (charge reversal), which is more amenable to enter cancer cells. Afterwards, manganese dioxide nanorods could catalyse the reaction of excess H2O2 in tumour microenvironment to generate active oxygen, so as to change the hypoxic environment in tumour, and achieve a pH‐responsive for slow release of PD‐L1. After the ICG was irradiated by infrared light, a large amount of singlet oxygen was generated, thereby enhancing the therapeutic effect and reducing toxicity in vivo. Besides, mesoporous PDA with indocyanine green photothermal agent could have a local heat up quickly under the near‐infrared light to kill cancer cells, thereby enhancing therapeutic efficacy. Accordingly, this mesoporous PDA composite nanorods shed a light on bladder tumour treatment. [ABSTRACT FROM AUTHOR]

TiO2−Ag2O composite nanorods with various Ag2O configurations were synthesized by a two-step process, in which the core TiO2 nanorods were prepared by the hydrothermal method and subsequently the Ag2O crystals were deposited by sputtering deposition. Two types of the TiO2−Ag2O composite nanorods were fabricated; specifically, discrete Ag2O particle-decorated TiO2 composite nanorods and layered Ag2O-encapsulated TiO2 core−shell nanorods were designed by controlling the sputtering duration of the Ag2O. The structural analysis revealed that the TiO2−Ag2O composite nanorods have high crystallinity. Moreover, precise control of the Ag2O sputtering duration realized the dispersive decoration of the Ag2O particles on the surfaces of the TiO2 nanorods. By contrast, aggregation of the massive Ag2O particles occurred with a prolonged Ag2O sputtering duration; this engendered a layered coverage of the Ag2O clusters on the surfaces of the TiO2 nanorods. The TiO2−Ag2O composite nanorods with different Ag2O coverage morphologies were used as chemoresistive sensors for the detection of trace amounts of NO2 gas. The NO2 gas-sensing performances of various TiO2−Ag2O composite nanorods were compared with that of pristine TiO2 nanorods. The underlying mechanisms for the enhanced sensing performance were also discussed.

WO3−SnO2 composite nanorods were synthesized by combining hydrothermal growth of tapered tungsten trioxide (WO3) nanorods and sputter deposition of thin SnO2 layers. Crystalline SnO2 coverage layers with thicknesses in the range of 13−34 nm were sputter coated onto WO3 nanorods by controlling the sputtering duration of the SnO2. The X-ray diffraction (XRD) analysis results demonstrated that crystalline hexagonal WO3−tetragonal SnO2 composite nanorods were formed. The microstructural analysis revealed that the SnO2 coverage layers were in a polycrystalline feature. The elemental distribution analysis revealed that the SnO2 thin layers homogeneously covered the surfaces of the hexagonally structured WO3 nanorods. The WO3−SnO2 composite nanorods with the thinnest SnO2 coverage layer showed superior gas-sensing response to 100−1000 ppm acetone vapor compared to other composite nanorods investigated in this study. The substantially improved gas-sensing responses to acetone vapor of the hexagonally structured WO3 nanorods coated with the SnO2 coverage layers are discussed in relation to the thickness of SnO2 coverage layers and the core−shell configuration of the WO3−SnO2 composite nanorods.

In this study, ZnO−WO3 composite nanorods were synthesized through a combination of hydrothermal growth and sputtering method. The structural analysis results revealed that the as-synthesized composite nanorods had a homogeneous coverage of WO3 crystallite layer. Moreover, the ZnO−WO3 composite nanorods were in a good crystallinity. Further post-annealed the composite nanorods in a hydrogen-containing atmosphere at 400 °C induced the local phase transformation between the ZnO and WO3. The ZnO−WO3 composite nanorods after annealing engendered the coexistence of ZnWO4 and WO3 phase in the shell layer which increased the potential barrier number at the interfacial contact region with ZnO. This further enhanced the ethanol gas-sensing response of the pristine ZnO−WO3 composite nanorods. The experimental results herein demonstrated a proper thermal annealing procedure of the binary composite nanorods is a promising approach to modulate the gas-sensing behavior the binary oxide composite nanorods.

ZnO-ZnS core-shell nanorods are synthesized by combining the hydrothermal method and vacuum sputtering. The core-shell nanorods with variable ZnS shell thickness (7–46 nm) are synthesized by varying ZnS sputtering duration. Structural analyses demonstrated that the as-grown ZnS shell layers are well crystallized with preferring growth direction of ZnS (002). The sputtering-assisted synthesized ZnO-ZnS core-shell nanorods are in a wurtzite structure. Moreover, photoluminance spectral analysis indicated that the introduction of a ZnS shell layer improved the photoexcited electron and hole separation efficiency of the ZnO nanorods. A strong correlation between effective charge separation and the shell thickness aids the photocatalytic behavior of the nanorods and improves their photoresponsive nature. The results of comparative degradation efficiency toward methylene blue showed that the ZnO-ZnS nanorods with the shell thickness of approximately 17 nm have the highest photocatalytic performance than the ZnO-ZnS nanorods with other shell layer thicknesses. The highly reusable catalytic efficiency and superior photocatalytic performance of the ZnO-ZnS nanorods with 17 nm-thick ZnS shell layer supports their potential for environmental applications. [ABSTRACT FROM AUTHOR]

In this work, synthesis, characterization and temperature dependent alternating current (AC) conductivity studies on copper decorated and zinc oxide embedded polypyrrole (PPy/Cu–ZnO) ternary composite nanorods are reported. The composite nanorods were prepared by mechanical mixing of chemically synthesized copper decorated polypyrrole (PPy/Cu composite) with zinc oxide (ZnO). The so prepared nanorods were thoroughly characterized using TEM, SEM, FTIR and XRD techniques. Significant morphological change in the form of solid nanorods of the ternary composite was confirmed from its TEM image. The surface morphology of the composite nanorods was shown to be porous hinting that these nanorods have good prospects for gas sensing applications. The AC conductivities of PPy, PPy/Cu composite and PPy/Cu–ZnO composite nanorods were studied in the frequency range 100 Hz to 5 MHz over a temperature range 303 K–373 K. The increased AC conductivity of the composite nanorods as compared to those of PPy/Cu composite and PPy is discussed on the basis of interfacial effects and supported theoretically on the basis of correlated barrier hopping (CBH) model. [ABSTRACT FROM AUTHOR]

N,N'-Dicarboxy methyl perylene diimide-coated CeO 2 nanorods (PDI/CeO 2 NR) were synthesized via an ultrasonic-assisted method. PDI/CeO 2 exhibits the superb mimic peroxidase functions confirmed by the catalyzed oxidation of TMB by hydrogen peroxide in less than 60 s along with color transformation from colorless to blue. The catalytic mechanism was confirmed to be an electronic transfer mechanism by fluorescence experiment. Thus, a visual colorimetric sensor was constructed for hydrogen peroxide detection with a low detection limit (LOD = 2.23 μM). Comparing the inhibition effects of l-cysteine (Cys), ascorbic acid (AA) and glutathione (GSH) on the catalytic oxidation of TMB, it can be found that they possessed different types of inhibition on the oxidation of TMB by H 2 O 2 using PDI/CeO 2 , and AA has better antioxidant effect, followed by Cys and GSH. On the basis of the excellent antioxidant effect of AA, a low-cost colorimetric sensor was also used to detect AA, and a lower LOD value (0.68 μM) was obtained in the linear range of 5.0-30 μM.

TiO2–Ag2O composite nanorods with various Ag2O configurations were synthesized by a two-step process, in which the core TiO2 nanorods were prepared by the hydrothermal method and subsequently the Ag2O crystals were deposited by sputtering deposition. Two types of the TiO2–Ag2O composite nanorods were fabricated; specifically, discrete Ag2O particle-decorated TiO2 composite nanorods and layered Ag2O-encapsulated TiO2 core–shell nanorods were designed by controlling the sputtering duration of the Ag2O. The structural analysis revealed that the TiO2–Ag2O composite nanorods have high crystallinity. Moreover, precise control of the Ag2O sputtering duration realized the dispersive decoration of the Ag2O particles on the surfaces of the TiO2 nanorods. By contrast, aggregation of the massive Ag2O particles occurred with a prolonged Ag2O sputtering duration; this engendered a layered coverage of the Ag2O clusters on the surfaces of the TiO2 nanorods. The TiO2–Ag2O composite nanorods with different Ag2O coverage morphologies were used as chemoresistive sensors for the detection of trace amounts of NO2 gas. The NO2 gas-sensing performances of various TiO2–Ag2O composite nanorods were compared with that of pristine TiO2 nanorods. The underlying mechanisms for the enhanced sensing performance were also discussed. [ABSTRACT FROM AUTHOR]

WO3–SnO2 composite nanorods were synthesized by combining hydrothermal growth of tapered tungsten trioxide (WO3) nanorods and sputter deposition of thin SnO2 layers. Crystalline SnO2 coverage layers with thicknesses in the range of 13–34 nm were sputter coated onto WO3 nanorods by controlling the sputtering duration of the SnO2. The X-ray diffraction (XRD) analysis results demonstrated that crystalline hexagonal WO3–tetragonal SnO2 composite nanorods were formed. The microstructural analysis revealed that the SnO2 coverage layers were in a polycrystalline feature. The elemental distribution analysis revealed that the SnO2 thin layers homogeneously covered the surfaces of the hexagonally structured WO3 nanorods. The WO3–SnO2 composite nanorods with the thinnest SnO2 coverage layer showed superior gas-sensing response to 100–1000 ppm acetone vapor compared to other composite nanorods investigated in this study. The substantially improved gas-sensing responses to acetone vapor of the hexagonally structured WO3 nanorods coated with the SnO2 coverage layers are discussed in relation to the thickness of SnO2 coverage layers and the core–shell configuration of the WO3–SnO2 composite nanorods. [ABSTRACT FROM AUTHOR]

In this study, ZnO–WO3 composite nanorods were synthesized through a combination of hydrothermal growth and sputtering method. The structural analysis results revealed that the as-synthesized composite nanorods had a homogeneous coverage of WO3 crystallite layer. Moreover, the ZnO–WO3 composite nanorods were in a good crystallinity. Further post-annealed the composite nanorods in a hydrogen-containing atmosphere at 400 °C induced the local phase transformation between the ZnO and WO3. The ZnO–WO3 composite nanorods after annealing engendered the coexistence of ZnWO4 and WO3 phase in the shell layer which increased the potential barrier number at the interfacial contact region with ZnO. This further enhanced the ethanol gas-sensing response of the pristine ZnO–WO3 composite nanorods. The experimental results herein demonstrated a proper thermal annealing procedure of the binary composite nanorods is a promising approach to modulate the gas-sensing behavior the binary oxide composite nanorods. [ABSTRACT FROM AUTHOR]