Synthesis of carbon nanotubes (CNTs) was performed by using a laminar premixed flame burner at open atmospheric condition. The growth of CNTs on the substrate was supported catalytically by a ...transition metal under high temperature, hydrocarbon-rich environment. Analysis of the CNTs using high resolution electron microscope reveals the structure of synthesised nano-materials in disarray, clustered and tubular form. The graphitic structure of the CNTs are rather similar for all fuel-rich equivalence ratios tested, with an average diameter of ∼11–13 nm. Removal of the amorphous carbon and catalyst in the CNTs was performed via purification treatment using H2O2 and HCl solutions. Detail characterisation indicates the oxidation temperature of purified CNTs ranges between 497 and 529 °C. Deconvolution of the Raman spectra in the range of 900–1800 cm−1 shows the distinct characteristic bands of CNTs with IG/ID ratio of 0.66–0.72 for all the samples tested. In addition, the high level carbon concentration and sp2 CC bond in the CNTs is shown by X-ray photoelectron spectroscopy analysis. The present study demonstrates that CNTs can be effectively synthesised from fuel-rich hydrocarbon flames at ϕ = 1.8–2.0 supported by nickel-based substrate.
•Carbon nanotubes (CNTs) are synthesised by hydrocarbon-rich premixed flames supported by Ni catalyst.•CNT structure shows layers of wall in the tube with diameter in the range of 11–13 nm and d200 value of ∼0.32 nm.•Purification of CNTs with H2O2 and HCl solutions leads to higher purity.•TGA analysis shows the oxidation temperature of CNTs is ∼500 °C.•XPS analysis shows 88.3% of carbon concentration in the CNTs with 71.3% of sp2 CC bond.
The concept of wearables is rapidly evolving from flexible polymer-based devices to textile electronics. The reason for this shift is the ability of textiles to ensure close contact with the skin, ...resulting in comfortable, lightweight, and compact “always with you” sensors. We are contributing to this polymer-textile transition by introducing a novel and simple way of laser intermixing of graphene with synthetic fabrics to create wearable sensing platforms. Our hybrid materials exhibit high electrical conductivity (87.6 ± 36.2 Ω/sq) due to the laser reduction of graphene oxide and simultaneous laser-induced graphene formation on the surface of textiles. Furthermore, the composite created between graphene and nylon ensures the durability of our materials against sonication and washing with detergents. Both of these factors are essential for real-life applications, but what is especially useful is that our free-form composites could be used as-fabricated without encapsulation, which is typically required for conventional laser-scribed materials. We demonstrate the exceptional versatility of our new hybrid textiles by successfully recording muscle activity, heartbeat, and voice. We also show a gesture sensor and an electrothermal heater embedded within a single commercial glove. Additionally, the use of these textiles could be extended to personal protection equipment and smart clothes. We achieve this by implementing self-sterilization with light and laser-induced functionalization with silver nanoparticles, which results in multifunctional antibacterial textiles. Moreover, incorporating silver into such fabrics enables their use as surface-enhanced Raman spectroscopy sensors, allowing for the direct analysis of drugs and sweat components on the clothing itself. Our research offers valuable insights into simple and scalable processes of textile-based electronics, opening up new possibilities for paradigms like the Internet of Medical Things.
Novel dual-/tri-band polarization rotation surfaces (PRSs) based on orthogonally inserted coupling slotlines are proposed, which can rotate a linearly polarized incident wave by 90°. The element of ...PRS comprises two coupling branches, and each branch is constructed by two coupled slotlines etched on the orthogonal printed circuit boards (PCBs). Under a vertically or horizontally polarized incident wave, the spatial wave is transformed into the guided wave by the end of one slotline and coupled to another slotline layered in the orthogonal direction, thus resulting in 90° polarization rotation. By approximately adjusting the coupling strength of the couped slotlines, dual-band and triband with second-order filtering responses can be achieved. Moreover, two extra straight slotlines are etched on the two orthogonal PCBs, respectively, to generate transmission zeros (TZs) to enhance the frequency selectivity between passbands. The simulation exhibit good dual-/tri-band filtering responses with sharp band edges, stable response characteristic for oblique angles of incidence, and high polarization conversion ratio (PCR).
With the continuous growth of the human population and new challenges in the quality of life, it is more important than ever to diagnose diseases and pathologies with high accuracy, sensitivity and ...in different scenarios from medical implants to the operation room. Although conventional methods of diagnosis revolutionized healthcare, alternative analytical methods are making their way out of academic labs into clinics. In this regard, surface-enhanced Raman spectroscopy (SERS) developed immensely with its capability to achieve single-molecule sensitivity and high-specificity in the last two decades, and now it is well on its way to join the arsenal of physicians. This review discusses how SERS is becoming an essential tool for the clinical investigation of pathologies including inflammation, infections, necrosis/apoptosis, hypoxia, and tumors. We critically discuss the strategies reported so far in nanoparticle assembly, functionalization, non-metallic substrates, colloidal solutions and how these techniques improve SERS characteristics during pathology diagnoses like sensitivity, selectivity, and detection limit. Moreover, it is crucial to introduce the most recent developments and future perspectives of SERS as a biomedical analytical method. We finally discuss the challenges that remain as bottlenecks for a routine SERS implementation in the medical room from in vitro to in vivo applications. The review showcases the adaptability and versatility of SERS to resolve pathological processes by covering various experimental and analytical methods and the specific spectral features and analysis results achieved by these methods.
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•SERS ultrasensitivity and specificity are critical to medical applications.•We discuss details on different strategies to integrate SERS in pathology.•Necrosis, apoptosis, and details behind cell-death can be accessed with SERS.•Pathologies including inflammation, hypoxia, tumors, infections are thoroughly reviewed.
In previous research, there have been more investigations on methanol blended with other fuels such as diesel, biodiesel, gasoline, etc., but fewer investigations on methanol with ignition additives ...as a mono-fuel. To better understand the methanol mono-fuel combustion characteristics and to further apply them, a combined experimental and simulation study of methanol in a Scania heavy-duty compression ignition (CI) engine was carried out in this work. The experiments consisted of four groups with variable injection timings, variable fraction of ignition additives, variable charge air temperatures, and variable overall excess air ratios/power sweeps. Heat release rate (HRR), cylinder pressure, ignition delay and indicated efficiency were analyzed for each case. The analysis showed that the combustion type was partially premixed combustion (PPC) in some cases and diesel-like combustion in the rest. By observing all cases, the shortest ignition delay was 14.1°, and the longest was 22.8°. The indicated efficiencies were in the range of 0.35 to 0.43. Simulations and validation analyses were performed for all cases by a multi-packets model. The physical and chemical ignition delays were predicted. The physical ignition delays were in the range of 4.25 to 8.10°, and the chemical ignition delays were in the range of 6.66 to 17.1°. The chemical ignition delay was always longer than the physical one. This indicates that chemical ignition delay has to be prioritized to improve the ignition performance of methanol fuel.
Abstract The heterogeneity and immunosuppression microenvironment of ovarian cancer seriously restrict the efficiency of monomodal treatment. Emerging multimodal therapy strategies based on ...sonodynamic therapy with enhanced antitumor effects have attracted intensive attention in the quest to combat cancer. However, exploring highly efficient sonosensitizers integrating chemodynamic/sonodynamic/immunotherapies with reversing immunosuppressive tumor microenvironment (TME) capacity is urgently desired but remains challenging. Here, a facile strategy is designed to synthesize immunomodulating sonocatalytic nanoagents (IrT‐SCN) with dual‐functional Ir‐N centers and narrow bandgap for reversing immunosuppression and potentiating ovarian cancer immunotherapy. IrT‐SCN with dual‐functional centers Ir‐N 2 and Ir‐N 4 and conjugated networks show a reduced bandgap, moderate interaction with H 2 O 2 , and efficient production of reactive oxygen species (ROS). Such ROS capabilities include: 1) utilizing H 2 O 2 in TME to catalytically generate potent O 2 , as well as abundant superoxide anion (•O 2 − ) and singlet oxygen ( 1 O 2 ) radicals; 2) external ultrasound (US) irradiation can also boost the production of 1 O 2 simultaneously; 3) M1 polarization of tumor‐associated macrophages and enhanced immune effect can promote the outcome of cancer treatment. This finding provides proof‐of‐concept evidence for the future development of immunomodulating sonocatalytic nanoagents for oncological treatments and other ROS‐related biomedical fields.
The healing of tendon injury is often hindered by peritendinous adhesion and poor regeneration caused by the accumulation of reactive oxygen species (ROS), development of inflammatory responses, and ...the deposition of type-III collagen. Herein, an extracellular vesicles (EVs)-cloaked enzymatic nanohybrid (ENEV) was constructed to serve as a multifaceted biocatalyst for ultrasound (US)-augmented tendon matrix reconstruction and immune microenvironment regulation. The ENEV-based biocatalyst exhibits integrated merits for treating tendon injury, including the efficient catalase-mimetic scavenging of ROS in the injured tissue, sustainable release of Zn2+ ions, cellular uptake augmented by US, and immunoregulation induced by EVs. Our study suggests that ENEVs can promote tenocyte proliferation and type-I collagen synthesis at an early stage by protecting tenocytes from ROS attack. The ENEVs also prompted efficient immune regulation, as the polarization of macrophages (Mφ) was reversed from M1φ to M2φ. In a rat Achilles tendon defect model, the ENEVs combined with US treatment significantly promoted functional recovery and matrix reconstruction, restored tendon morphology, suppressed intratendinous scarring, and inhibited peritendinous adhesion. Overall, this study offers an efficient nanomedicine for US-augmented tendon regeneration with improved healing outcomes and provides an alternative strategy to design multifaceted artificial biocatalysts for synergetic tissue regenerative therapies.
A novel optical fiber filter based on a strongly chirped sampled Bragg grating is proposed for wavelength-division-multiplexing (WDM) system applications. It features in multiple equalized passbands ...with flat-top steep-edge nearly linear phase response and high transmittance. Refractive index modulation amplitude with Gaussian spatial profile is used within the samples, which contributes to the marked improvement of the filter performance. Furthermore, there are also multiple flat and equalized stopbands to be used as multichannel optical add/drop filters in a WDM system.
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