In the paper, we propose an elliptical photonic crystal fiber sensor with an open ring channel, which could enhance the sensor performance. Gold is employed as the plasmonic material and coated on ...open ring channel. Using the finite element method, the wavelength sensitivity, the amplitude sensitivity, and the optical spectrum leakage from the fiber core to the sample channels are examined, and the influence of structural parameters on the sensor performance is investigated. The numerical results show that the proposed sensor exhibits a wide detection range of the refractive index (RI) from 1.20 to 1.40, the maximum wavelength sensitivity is 21,000 nm/RIU, where RIU is the RI unit, and the maximum amplitude sensitivity of 455.45 RIU
−1
is obtained for RI of 1.33. Moreover, the feasibility of the multi-function detection to identify fluorine-containing organics, glucose concentration, and pathogens in water is also numerically investigated.
Phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), is a light-activated local treatment modality that is under intensive preclinical and clinical investigations for ...cancer. To enhance the treatment efficiency of phototherapy and reduce the light-associated side effects, it is highly desirable to improve drug accumulation and precision guided phototherapy for efficient conversion of the absorbed light energy to reactive oxygen species (ROS) and local hyperthermia. In the present study, a programmed assembly strategy was developed for the preparation of human serum albumin (HSA)-indocyanine green (ICG) nanoparticles (HSA-ICG NPs) by intermolecular disulfide conjugations. This study indicated that HSA-ICG NPs had a high accumulation with tumor-to-normal tissue ratio of 36.12 ± 5.12 at 24 h and a long-term retention with more than 7 days in 4T1 tumor-bearing mice, where the tumor and its margin, normal tissue were clearly identified via ICG-based in vivo near-infrared (NIR) fluorescence and photoacoustic dual-modal imaging and spectrum-resolved technology. Meanwhile, HSA-ICG NPs efficiently induced ROS and local hyperthermia simultaneously for synergetic PDT/PTT treatments under a single NIR laser irradiation. After an intravenous injection of HSA-ICG NPs followed by imaging-guided precision phototherapy (808 nm, 0.8 W/cm2 for 5 min), the tumor was completely suppressed, no tumor recurrence and treatments-induced toxicity were observed. The results suggest that HSA-ICG NPs generated by programmed assembly as smart theranostic nanoplatforms are highly potential for imaging-guided cancer phototherapy with PDT/PTT synergistic effects.
Flexible in-plane architecture micro-supercapacitors (MSCs) are competitive candidates for on-chip miniature energy storage applications owing to their light weight, small size, high flexibility, as ...well as the advantages of short charging time, high power density, and long cycle life. However, tedious and time-consuming processes are required for the manufacturing of high-resolution interdigital electrodes using conventional approaches. In contrast, the laser processing technique enables high-efficiency high-precision patterning and advanced manufacturing of nanostructured electrodes. In this review, the recent advances in laser manufacturing and patterning of nanostructured electrodes for applications in flexible in-plane MSCs are comprehensively summarized. Various laser processing techniques for the synthesis, modification, and processing of interdigital electrode materials, including laser pyrolysis, reduction, oxidation, growth, activation, sintering, doping, and ablation, are discussed. In particular, some special features and merits of laser processing techniques are highlighted, including the impacts of laser types and parameters on manufacturing electrodes with desired morphologies/structures and their applications on the formation of high-quality nanoshaped graphene, the selective deposition of nanostructured materials, the controllable nanopore etching and heteroatom doping, and the efficient sintering of nanometal products. Finally, the current challenges and prospects associated with the laser processing of in-plane MSCs are also discussed. This review will provide a useful guidance for the advanced manufacturing of nanostructured electrodes in flexible in-plane energy storage devices and beyond.
Flexible battery-type in-plane hybrid micro-supercapacitors (IHMSCs), which combine fast charging rate of micro-supercapacitors and high energy density of batteries, provide great potentials for ...flexible microdevices. However, their low-efficiency, high-cost process and limited energy density still hinder their practical applications. Herein, we report the high-efficient fabrication of Fe3O4 nanoparticle-anchored laser-induced graphene (LIG/Fe3O4) with hierarchical porous structures on a flexible substrate wherein aggregated Fe3O4 nanoparticles (~24.08 nm) with mesopores are self-deposited onto macroporous LIG scaffolds by laser in one step. The unique 3D structures in LIG/Fe3O4 give rise to superhydrophilic and capillary effects with a pumping capacity of up to 0.096 μm in water, resulting in continuous superior wettability between electrodes and water-based electrolyte. Benefiting from the reversible H+ ion (de)intercalation reaction with Fe3O4 nanoparticles, the resulting IHMSCs based on LIG/Fe3O4 as the anode and LIG as the cathode deliver an ultrahigh areal capacitance of 719.28 mF/cm2, which is over 100 times higher than that of LIG micro-supercapacitors, and an areal energy density of 60.20 μWh/cm2, superior to those of most previously reported IHMSCs. Furthermore, the IHMSCs exhibit a good cycling stability and mechanical flexibility. Our method is applicable to other capillary-functionalized flexible electronics and may open new avenues for large-scale industrial fabrication of flexible electronics.
Display omitted
•High-efficient fabrication of Fe3O4 nanoparticle-anchored porous graphene (LIG/Fe3O4) on flexible substrate is achieved.•Self-deposition of aggregated Fe3O4 nanoparticles with mesopores onto macroporous graphene is conducted by direct laser writing.•The hierarchical pore structures give rise to superhydrophilic and excellent capillary effects in water.•The LIG/Fe3O4 in-plane micro-supercapacitors (IMSCs) deliver an capacitance of 719 mF/cm2, superior to those of most reported IMSCs.
Laser-induced graphene (LIG) films and their derivatives have been regarded as one of the most outstanding functional flexible electrodes in the past decade, which will transform society and enable ...new devices and developments. The aim of this Special Issue is to provide a scientific platform for scholars in the LIG field to present their recent research towards a deeper understanding of forming mechanism, structure/ morphology, properties and behaviors of LIG films. This Special Issue gives readers the possibility to gain new insights into the applications of LIG films in flexible electronics, including mechanical/temperature/gas/electrochemical sensors, micro-supercapacitors, actuators, electrocatalysis, solid-state triboelectric nanogenerators, Joule heater, etc. We believe that the papers published in this Special Issue will provide a useful guidance for the manufacturing of nanostructured LIG electrodes in flexible electronics.
•A new model of random pulse sources with temporal multi-complex degree of coherence (TMCDOC) is introduced.•The analytical formulas for the temporally spectral density and TMCDOC of the beam in the ...dispersive media are derived.•The pulse beams will evolve from a single pulse into multiple subpulses or flat-topped temporally average intensity.
Based on the coherence theory, the non-stationary optical fields with the complex degree of coherence (CDOC) are expanded from stationary fields, and random pulse sources with temporal multi-complex degree of coherence (TMCDOC) is introduced. Theoretical model for the random pulse sources with TMCDOC is established. The analytical transmission formulas for the temporally spectral density and TMCDOC of the pulse beam spreading through dispersive media are derived and its propagation properties in dispersive media are explored. One can find from the numerical results that the TMCDOC pulse beam will evolve from a single pulse at the source plane into N subpulses in the far field or produce far field spectral density with flat-topped profiles. The variation of the non-trivial phase of the CDOC can regulate the propagation angle of the TMCDOC pulse beam. Moreover, in case of the propagation in dispersive media with chirp coefficient s < 0, the TMCDOC pulse beam will exhibit self-focusing process, and its coherence curves will be reversed from the clockwise rotation in the near field to anticlockwise rotation in the far field.
Display omitted
•PEEK-Ti6Al4V composites were developed using powder bed fusion and vacuum infiltration.•PEEK-Ti6Al4V composites had higher compressive and flexural strengths than the Ti6Al4V ...lattices of equivalent elastic moduli.•PEEK-Ti6Al4V composites exhibited higher fatigue strength than the Ti6Al4V lattices of equivalent elastic moduli.•The enhancing mechanisms can be the alleviation of strut deformation and the resistance to crack propagation.
Comprehensive mechanical properties (high strength, good fatigue resistance and tunable stiffness) are significant for large and load-bearing implants, but still remain a challenge in practical applications. Polyetheretherketone (PEEK)-Ti6Al4V interpenetrating phase composites (IPCs) with comprehensive mechanical properties were developed using a two-step process: fabricating Ti6Al4V microlattices using powder bed fusion (PBF) and subsequently manufacturing PEEK-Ti6Al4V IPCs using vacuum infiltration. The strut defects in the Ti6Al4V microlattices induced by PBF process were filled with PEEK, and thus excellent interfacial connection was achieved. Mechanical tests, under both quasi-static loading conditions (compression and three-point bending conditions) and dynamic loading condition (three-point bending condition), were carried out on the PEEK-Ti6Al4V composites with low and high modulus (20.0 and 60.0 vol% Ti6Al4V) and the bare Ti6Al4V microlattices of equivalent elastic moduli. It was found that the composites had higher compressive and flexural strengths than the lattices. Moreover, the composites exhibited higher fatigue strength and longer fatigue life than the lattices. The fracture behaviors and the FEM simulation results revealed that the enhancing mechanisms for the PEEK-Ti6Al4V composites can be the alleviation of strut deformation and the resistance to crack propagation. Thus, the PEEK-Ti6Al4V composites can be promising materials for large and load-bearing implants.
A composite nonwoven fabric named CEF-NF in previous work was fabricated with carbon fibers (CFs) and polypropylene/polyethylene (PP/PE) core/sheath bicomponent fibers (denoted as ESFs). It holds ...great promise as an electromagnetic interference (EMI) shielding material, due to its good mechanical strength, excellent flexibility, ultra-thin thickness and remarkable electrical properties. This paper demonstrates a composite CEF-NF fabricated via two-step wet-papermaking/thermal-bonding processes. A flange coaxial test system was established to investigate the influences of material structure on EMI shielding effectiveness (EMI-SE) of CEF-NF fabrics in 30–1500MHz frequency range. Results indicate that the structure of a CEF-NF is highly correlated to its EMI-SE property, which increases with increasing areal density, fiber length and CF concentration. Under a set of optimal process parameters, the EMI-SE of CEF-NF with merely 40wt% of CF and 50g/m2 areal density can achieve a specific overall EMI-SE as high as 30.29dB, or 110dB·cm3/g—meeting commercial EMI requirements. Lastly, the ideal and actual EMI shielding mechanism were fully investigated and analyzed. It was found that the electrical percolation threshold of CEF-NF had a great influence on the actual absorption and reflection performance. At the conductivity threshold, CEF-NF showed high absorption performance.
Display omitted
•A composite nonwoven fabric works well in electromagnetic interface shielding.•Fabric structure affects its electromagnetic interface shielding effectiveness.•Conductivity percolation threshold affects the reflected and absorbed power of the fabric.•Carbon fiber concentration determines whether the EMI reflection or absorption is dominant.
To gain a more meaningful understanding of bone regeneration, it is essential to select an appropriate assessment method. Micro-computed tomography (Micro-CT) is widely used for bone regeneration ...because it provides a substantially higher spatial resolution. Dual-energy computed tomography (DECT) ensure shorter scan time and lower radiation doses during quantitative evaluation. Therefore, in this study, DECT and Micro-CT were used to evaluate bone regeneration. We created 18 defects in the tibial plateau of the rabbits and filled them with porous polyetheretherketone implants to promote bone regeneration. At 4, 8, and 12 weeks, Micro-CT and DECT were used to assess the bone repair in the defect region. In comparison to Micro-CT (152 ± 54 mg/cm
), the calcium density values and hydroxyapatite density values obtained by DECT DECT(Ca) and DECT(HAP) consistently achieved lower values (59 ± 25 mg/cm
, 126 ± 53 mg/cm
). In addition, there was a good association between DECT and Micro-CT (R = 0.98; R
= 0.96; DECT(Ca): y = 0.45x-8.31; DECT(HAP): y = 0.95x-17.60). This study highlights the need to use two different imaging methods, each with its advantages and disadvantages, to better understand the bone regeneration process.
PDF
