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Bluetooth low energy (LE) devices have been widely used in the Internet of Things (IoT) and wireless personal area networks (WPAN). However, attackers may compromise user privacy by tracking the addresses of the LE device. The resolvable private address (RPA) mechanism provides address privacy protection for the LE device. Similar to Zhang and Lin's work in CCS 2022, we investigate the privacy of the RPA mechanism in this paper. Our contributions are threefold. First, we discover that the RPA mechanism has a privacy weakness. The attacker can track the targeted device by exploiting the runs of the RPA mechanism when he intercepts the targeted device's obsolete RPA value. Second, we propose an improved RPA mechanism to overcome the privacy weakness in the RPA mechanism. The improved RPA mechanism leads to a small amount of extra overheads without requiring modification to the basic cryptographic tools used in the standard specification. Third, we formalize a privacy model to capture the address privacy of the RPA mechanisms. Our improved RPA mechanism provides enhanced privacy guarantees to Bluetooth LE devices in wireless personal applications. [ABSTRACT FROM AUTHOR]

Hollow transition metal oxides have important applications in the degradation of organic pollutants by a photo-Fenton-like process. Herein, uniform, highly dispersible hollow CuFe2O4/C nanospheres (denoted as CFO/C-PNSs) were prepared by a one-pot approach. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images verified that the CFO/C-PNS catalyst mainly presents hollow nanosphere morphology with a diameter of 250 ± 30 nm. Surprisingly, the photodegradation test results revealed that CFO/C-PNSs had an excellent photocatalytic performance in the elimination of various organic contaminants under visible light through the efficient Fenton catalytic process. Due to the unique hollow structure formed by the assembly of ultra-small CFO/C subunits, the catalyst exposes more reaction sites, improving its photocatalytic activity. More importantly, the resulting magnetically separable CFO/C-PNSs exhibited excellent stability. Finally, the possible photocatalytic reaction mechanism of the CFO/C-PNSs was proposed, which enables us to have a clearer understanding of the photo-Fenton mechanism. Through a series of characterization and analysis of degradation behavior of CFO/C-PNS samples over antibiotic degradation and Cr(VI) reduction, •OH radicals generated from H2O2 decomposition played an essential role in enhancing the reaction efficiency. The present work offered a convenient method to fabricate hollow transition metal oxides, which provided impetus for further development in environmental and energy applications. Highlights: Novel hollow CuFe2O4/C nanospheres were prepared by a facile and cost-effective method. CuFe2O4/C exhibited excellent photo-Fenton-like performance for antibiotic degradation. Outstanding photocatalytic performance was attributed to the specific hollow cavity-porous structure. A possible mechanism for H2O2 activation over hollow CuFe2O4/C nanospheres was detailed and discussed. [ABSTRACT FROM AUTHOR]

SnO 2 -doped PLZT (9/65/35) transparent ceramics have been prepared by the hot press sintering method. The microstructure, dielectric, ferroelectric, and electrostrictive properties of the materials were examined and analyzed. All the samples present typical relaxor ferroelectric characteristics. Owing to the lowering of the long-range order by Sn4+ doping, the T m peaks decrease gradually with the increasing SnO 2 content. Compared with the high field-induced strains, the antiferroelectric-ferroelectric phase transformation in all the PLZST samples can be induced under the electric field. The electrostrictive property of the PLZT (9/65/35) ceramics was obviously improved by the Sn4+ ion doping. In addition, the polarization-related electrostrictive coefficient Q 33 increased gradually from 0.024 m4/C2 to 0.027 m4/C2 as the SnO 2 content increased from 0.0 wt % to 0.6 wt %. [ABSTRACT FROM AUTHOR]

Smart card data is increasingly used to investigate passenger behavior and the demand characteristics of public transport. The destination estimation of public transport is one of the major concerns for the implementation of smart card data. In recent years, numerous studies concerning destination estimation have been carried out--most automatic fare collection (AFC) systems only record boarding information but not passenger alighting information. This study provides a comprehensive review of the practice of using smart card data for destination estimation. The results show that the land use factor is not discussed in more than three quarters of papers and sensitivity analysis is not applied in two thirds of papers. In addition, the results are not validated in half the relevant studies. In the future, more research should be done to improve the current model, such as considering additional factors or making sensitivity analysis of parameters as well as validating the results with multi-source data and new methods. [ABSTRACT FROM AUTHOR]

Wehave systematically investigated the effect of physicochemicalconditions, such as pH, salt concentration, and DNA/nanoparticle ratio,on the chemical conjugation process and structural and optical stabilityof carboxyl-functionalized quantum dots (QDs) functionalized withamino-modified DNA. We reveal the relationship between aqueous conditionsand the amount of DNA conjugated on QDs, colloidal stability, andyield of the final QD-DNA conjugates. By carefully adjusting the environmentalvariables we have successfully achieved up to 20 DNA strands conjugatedper QD, and demonstrated how this number can be tuned. The fabricatedQD-DNA conjugates are dispersed and optically stable in salted solutionsfor over a month. We have also evaluated the involved interparticleinteractions to explain the solution behavior of QD-DNA conjugates.Our results provide a basic understanding of the physiochemical processesgoverning a nanoparticle–biomolecule conjugation and the structuralstability of the formed conjugates. Such fabricated QD-DNA conjugatesmight be of great benefit for programmable assemblies of opticallyactive nanomaterials and for emerging biosensing methods based onnanomaterials. [ABSTRACT FROM AUTHOR]

Although dynamic traffic control and traffic assignment are intimately connected in the framework of Intelligent Transportation Systems (ITS), they have been developed independent of one another by most existing research. Conventional methods of signal timing optimization assume given traffic flow pattern, whereas traffic assignment is performed with the assumption of fixed signal timing. This study develops a bi-level programming formulation and heuristic solution approach (HSA) for dynamic traffic signal optimization in networks with time-dependent demand and stochastic route choice. In the bi-level programming model, the upper level problem represents the decision-making behavior (signal control) of the system manager, while the user travel behavior is represented at the lower level. The HSA consists of a Genetic Algorithm (GA) and a Cell Transmission Simulation (CTS) based Incremental Logit Assignment (ILA) procedure. GA is used to seek the upper level signal control variables. ILA is developed to find user optimal flow pattern at the lower level, and CTS is implemented to propagate traffic and collect real-time traffic information. The performance of the HSA is investigated in numerical applications in a sample network. These applications compare the efficiency and quality of the global optima achieved by Elitist GA and Micro GA. Furthermore, the impact of different frequencies of updating information and different population sizes of GA on system performance is analyzed. [ABSTRACT FROM AUTHOR]

The reverse transformation (from ferroelectric to paraelectric phase) temperature in aged ferroeletric lead lanthanum titanate ceramics is measured precisely by differential scanning calorimetry (DSC). It is observed that the transformation temperature increases with increasing aging time, indicating ferroelectric phase is stabilized by aging. This behavior is similar to those in ferroelectric single crystal barium titanate. The origin of the stabilization effect in the system is discussed with respect to the diffusion of point defects. [ABSTRACT FROM AUTHOR]

Controllable assembly of three-dimensional (3D) superlattices composed of different types of nanoscale objects opens new opportunities for material fabrication. Herein we show the successful assembly of heterogeneous 3D structures from gold nanoparticles (AuNPs) and quantum dots (QDs) using DNA encoding. By applying synchrotron-based small-angle X-ray scattering, we found that AuNPs and QDs are positioned in a body-centered cubic lattice, while each particle type, AuNP and QD, is arranged in a simple-cubic manner. Our studies demonstrate a route for assembly of integrated heterogeneous 3D structures from different nano-objects by DNA-encoded interactions. [ABSTRACT FROM AUTHOR]

Abstract: The ultraviolet–visible spectra of the pure barium strontium titanate (Ba0.72Sr0.28TiO3) and the Fe3+-doped Ba0.72Sr0.28TiO3 were measured. The pure barium strontium titanate exhibited an ultraviolet (UV) absorption effect. The addition of Fe2O3 resulted in an increase of absorption wavelength. This red-shift effect was very strong even though the amount of Fe3+ was very small. The similar phenomenon was also observed in pure BaTiO3 and Fe3+-doped BaTiO3. The UV-absorption behavior was discussed in terms of Fe3+ replacing Ti4+ in the titanate with perovskite structure. [Copyright &y& Elsevier]

We report that aging in ferroelectric state results in an increase of reverse transition temperature Tf in both BaTiO3 single crystal and Pb0.84La0.16Ti0.96O3 polycrystal. This indicates that the ferroelectric phase is gradually stabilized during aging below Curie temperature. The evolution of the stabilization with aging time in these two different systems obeys the same kinetic function, but with different relaxation time. This indicates that the stabilization effect of the two systems stems from a common origin. We suggest that the stabilization is due to a short-range ordering of point defects, driven by a symmetry-conforming tendency of point defects. [ABSTRACT FROM AUTHOR]

In this work, (100)-oriented Pr-doped (Bi0.5Na0.5)TiO3–BaTiO3 ferroelectric/photoluminescence film was fabricated on SrRuO3-electroded Pb(Mg1/3Nb2/3)O3–PbTiO3 single-crystal substrate. The phase structure, domain, ferroelectric, and photoluminescence performance were studied. Results indicated the Pr-BNBT thin film has pure phase structure, dense microstructure, and exhibited (100) orientation out of the plane. Well-defined ferroelectric hysteresis loop with the remanent polarization of ~ 18 μC/cm2 and obvious photoluminescence emission spectrum were obtained. Based on the piezoresponse force microscopy, the ferroelectric domain structure was characterized and the domain size was ~ 100 nm. The present ferroelectric/photoluminescence multifunctional thin film has potential for multifunctional MEMS actuator and optical devices. [ABSTRACT FROM AUTHOR]

A series of GdIG ceramics with good infrared transparency have been fabricated by a hot-press sintering process with vacuum/oxygen atmosphere. The effects of the powder synthesizing temperature and the ceramic sintering temperature on the phase structure and microstructure of the GdIG ceramics were examined and analyzed. The GdIG ceramic sample sintered at 1275 °C from the Gd 2 O 3 and Fe 2 O 3 powders pre-synthesized at 1000 °C demonstrated an exceptionally high infrared transmittance, it is ≥ 68% within the wavelength range of 1500–5000 nm (t = 0.5 mm). Furthermore, the magnetic and magneto-optic property of the GdIG ceramic samples were investigated and discussed. When a saturation external magnetic field of ∼50 mT acting on the GdIG ceramic sample, the specific Faraday rotation angles are about 104 deg./cm and 51 deg./cm at 1064 and 1550 nm wavelength respectively. It exhibits a good faraday effect of GdIG ceramics which is rarely reported until now. [ABSTRACT FROM AUTHOR]

In this study, the abilities two kinds of algae, Scenedesmus and Microcystis aeruginosa, and two kinds of bacteria, Rhodococcus and Raoultella planticola, to remove oestradiol when in a symbiotic system were investigated. The effects of the combined systems as well as the effects of each bacterium and algae alone were examined. We then compared the improvements from the bacteria-algae symbiosis systems with Microcystis aeruginosa and Raoultella planticola. The results showed that the oestradiol removal rate of the best system was 97.6%, while that from the Microcystis aeruginosa and Raoultella planticola system was 89%. Oestradiol has an effect on algal growth. The effects of algae on the growth of degrading bacteria were investigated. Degrading bacteria can affect the growth of algae. The symbiosis of bacteria and algae effectively removed oestradiol, with a removal rate that reached 97.6%. [ABSTRACT FROM AUTHOR]

In order to obtain the influence mechanism of the rotor noise and the local aerodynamic variation under different operating conditions, a novel discrete noise analysis strategy for the acoustic source localization is established. The analysis strategy has two aspects including the blade division method and the noise contribution calculation method. Firstly, the body-fitted rotor blade grids are preprocessed and refined at the division position before the flowfield simulation. Then, based on the flowfield result, the blade grids are divided into several blocks in the chordwise and spanwise directions, and the acoustic pressure of each block is predicted. Finally, a discriminant function for the contribution of the block to the rotor noise is proposed, and the acoustic source localization is carried out. The URANS equations and FW-H equations are used to capture high-fidelity flowfield and rotor acoustic pressure. Parameters such as the block position in different direction on the rotor blade and the collective pitches are quantified, and the relationship between air flow and aeroacoustics is discussed in detail. Some conclusions are obtained by analyzing the BO105 model rotor in hover. The acoustic pressure produced by the leading edge of the upper surface could cancel about 50% acoustic pressure of the remainder of these blocks. Increasing the force at this position will be benefit to the noise reduction. Acoustic source distribution is closely linked to the flow separation near the blade tip: the main acoustic source moves toward around 0.9 R section of the blade in the spanwise direction, and it moves from the leading edge towards the trailing edge in the chordwise direction. [ABSTRACT FROM AUTHOR]

[Display omitted] • The degradable porous materials were prepared from polycaprolactone grafted 2-ethyloctyl acrylate. • The polarity of the diluting solvent and its ability to form hydrogen bonds with water modify the pore structure. • The multiscale pore structure and the porosity of polyHIPE determine its sound and organic solvent absorption properties. The low melt strength of degradable polymers makes the preparation and pore structure manipulation of degradable porous polymers challenging, limiting their widespread utilization. Herein, we report the adoption of a high internal phase emulsion (HIPE) templating method to prepare degradable polymer porous materials with distinct characteristics, such as high porosity, a multiscale porous structure, and degradability. The prepolymer employed as the continuous phase was prepared by grafting degradable polycaprolactone onto 2-ethyloctyl acrylate. Subsequently, the viscosity of the oil phase and the density difference and interfacial tension between the oil and water phases were adjusted via the type and concentration of the diluting solvent. The porosity, pore structure, and degree of pore interconnectivity in the polymerized HIPE were adjusted by considering the physicochemical properties of the diluent and their influence on the oil–water partition at the HIPE interface. Additionally, the mechanisms underlying cavity and window formation in the prepared degradable polymer porous materials were explored. The prepared materials exhibited good sound absorption performance in the frequency range of 3000–4000 Hz, excellent organic solvent absorption capacity, and underwent rapid hydrolysis, with a mass loss of approximately 30% within the first 3 days, which escalated to approximately 80% within 1 month. The study findings provide a valuable reference for the preparation and structural regulation of degradable polymer porous materials, thereby fostering their future applications. [ABSTRACT FROM AUTHOR]

• Porous scaffold made from diatom frustules (DFs) and cellulose nanofibers (CNFs) through freeze-drying and carbonization. • Optimizing hierarchical pore characteristics significantly reduces the trade-off between leakage and crystallization. • Mesopores facilitate beeswax (BW) crystallization, while micropores prevent leakage. • COMSOL simulations show that micropores can convert macropores into leakage-proof structures. • The CNF/DF scaffold absorbs 93.7 wt% BW, with a melting enthalpy of 129.8 J/g. Utilization of phase change materials (PCMs) for thermal energy collection holds significant potential for energy storage and cost-effective thermal management. Confining solid–liquid PCMs within nanoporous scaffolds provides an effective strategy for creating shape-stabilized PCMs (ss-PCMs). However, the leakage and crystallization of PCM molecules within the pores significantly impact thermal energy storage, and balancing these factors remains challenging. Herein, we fabricated a hierarchical porous scaffold with tunable pore characteristics from artificially cultivated diatom frustules (DFs) and cellulose nanofibers (CNFs) through freeze-drying and carbonization. DF can regulate the pore characteristics of carbonized CNF (CCNF), transitioning from predominantly microporous to a mix of microporous and mesoporous, and ultimately to predominantly mesoporous. By optimizing hierarchical pore characteristics, the trade-off between leakage and crystallization is significantly alleviated; mesopores facilitate BW crystallization, while micropores prevent leakage. COMSOL simulations indicate that micropores can transform macropores or spaces into leakage-proof structures, enhancing scaffold's adsorption capability. Therefore, the CCNF/DF scaffold can absorb 93.7 wt% BW, achieving a melting enthalpy of 129.8 J/g. This work provides valuable guidance for efficient hierarchical porous frameworks for ss-PCMs. [ABSTRACT FROM AUTHOR]

• The evaporator was synthesized via high internal phase emulsion templating method. • The hydrophilic modification of polystyrene was realized by introducing EGDMA. • The high compressive modulus of 4.45 MPa and compressive stress of 4.60 MPa were achieved. • The high evaporation rates of 3.07 kg·m−2·h−1 for pure water and 3.01 kg·m−2·h−1 for seawater were achieved. Solar-driven interfacial evaporation enables the recovery of clean water resources from seawater and wastewater. However, evaporators that simultaneously exhibit good mechanical properties, excellent processability, and outstanding evaporation performance remains a major challenge. In this work, we have devhyeloped a solar-driven interfacial evaporator by creating a porous hydrophilic polystyrene (H-PS)/multi-walled carbon nanotube (MWCNT) composite using a high internal phase emulsion (HIPE) templating method, then coated with black paint for efficient photothermal conversion. The H-PS composite can be molded into large, integrated structures and easily processed into various shapes, which exhibits a compressive strength of 4.60 MPa at a strain of 80 %. The hydrophilic porous skeleton facilitates rapid water transport through capillary action and exhibits a low thermal conductivity of 0.193 W·m−1·K−1 for reducing the heat loss. In the evaporator, a highly efficient light-absorbing hierarchical structure is constructed on the skeleton through the synergistic interaction of MWCNT and black paint, achieving an absorbance of 95.9 % across the 250 to 2500 nm wavelength range. In such design, the evaporator receives a high evaporation rate of 3.07 kg·m−2·h−1 for pure water and 3.01 kg·m−2·h−1 for seawater under 1 sun illumination, demonstrating a promising candidate for the mass production and practical application of efficient solar-driven interfacial evaporators. [ABSTRACT FROM AUTHOR]

Coir fibers are commonly subjected to alkali treatment to eliminate impurities and tune their mechanical properties. However, this process can damage the fibers' microstructures, posing a challenge in significantly enhancing both strength and toughness simultaneously. Herein, we successfully enhanced both strength and toughness of coir fibers through a combined treatment with NaOH and sodium alginate aqueous solution. Coir fibers treated with 5 wt% NaOH solution, followed by 0.5 wt% sodium alginate solution, exhibit a tensile modulus of 2475.0 MPa, a tensile strength of 126.4 MPa, and a toughness of 30.7 MJ/m³, representing improvements of 57.1 %, 72.7 %, and 116.2 %, respectively, compared to the raw fibers. Mechanistic studies revealed that NaOH treatment effectively removes pectin, hemicellulose and lignin from coir fibers but introduces numerous defects. Sodium alginate can repair these defects by forming hydrogen bonds with the rich oxygen-containing group of coir fibers. The combined treatment also increases the crystallinity of coir fibers from 30.3 % for the raw fibers to 44.1 % by removing a large number of amorphous substances. Additionally, the combined treatment reduces the microfibril angle from ∼63.6° to ∼46.6° by elongating the helix structure and filling the gaps between helical fibers. Our cost-effective strategy not only promotes the applications of coir fibers but also provides guidance for the modification of other natural plant fibers. • CFs were modified by combined treatment with NaOH and sodium alginate aqueous solution. • The treated CFs exhibit a substantial increase in both strength and toughness. • The combined treatment is cost-effective and suitable for large-scale production. [ABSTRACT FROM AUTHOR]

Lithium zinc (Li0.35+xZn0.3Mn0.08Fe2.27O4±δ) ferrites with excess lithium concentrationxvarying from 0 to 0.08 in steps of 0.02 were prepared by conventional oxide ceramic method. XRD patterns confirm the spinel structure of Li0.35+xZn0.3Mn0.08Fe2.27O4±δferrites. According to the results of SEM photograph, excess lithium can compensate the volatilization of lithium during the sintering process and an appropriate amount of excess lithium is found to decrease the material porosity obviously, which improves the comprehensive performance of Li-Zn ferrites effectively. As the excess lithium concentration increases, the grain growth is restricted and the average grain size decreases. The bulk densitydand saturation magnetizationMsincrease firstly and then decrease with the increase of Li-excessx. In the meanwhile, the coercive forceHcshows a gradually increasing trend from 190A/m to 1036A/m, and the resistivity ρ has a monotonically increase due to the decrease of Fe2+irons. [ABSTRACT FROM AUTHOR]

Effective electromagnetic interference (EMI) shielding materials have garnered substantial interest for their efficacy in attenuating electromagnetic wave energy, ensuring data confidentiality, ensuring the operational stability of fragile electronic systems. To begin, artificially cultured diatom frustules (DF)-derived porous silica (DFPS) skeletons were constructed as templates in this study. Porous ceramics hot-pressed at 800 °C displayed a high compressive strength with a high specific surface area due to their three-dimensional (3D) multilayered and porous structures. Then, mechanically robust Ti 3 C 2 T x /DFPS composites with exceptional EMI shielding performance were fabricated by immersing porous DF-based ceramics into Ti 3 C 2 T x solutions and annealing in an argon environment to increase the materials' shielding efficiency (SE). The EMI SE of composites hot-pressed at 800 °C achieved the maximum EMI SE of 43.2 dB in the X-band and a compressive strength of 67.5 MPa, establishing a hitherto unreported balance of mechanical characteristics and shielding performance. Prolonged transmission paths, multiple dissipation, scattering and reflection of electromagnetic energy were achieved using a well-maintained hierarchical porous silica framework decorated with MXene, with adsorption caused by surface MXene serving as the primary shielding mechanism for the composites. Due to their superior overall performance, MXene/DFPS EMI shielding composites have a bright future in the aircraft sector as delicate electronic device components. [ABSTRACT FROM AUTHOR]

Highlights: [•] NIH/3T3 cells were exposed to individualized and agglomerated ZnO nanoparticles. [•] The cytotoxic response in growth media with and without phosphates was assessed. [•] With phosphates present, zinc phosphate formation enhanced cell death. [•] Agglomeration-dependent cell death only existed in the presence of phosphates. [•] Nanomaterial interactions with growth media constituents can be easily overlooked. [Copyright &y& Elsevier]

0.67Pb(Mg1/3Nb2/3)O3 (PMN)–0.33PbTiO3 (PT) ferroelectric ceramics has been selected as base component. Different content of B-site substitute (0.1, 0.5 and 1 mol%) were used to modify the base component. The specimens were synthesized by the columbite precursor method, and pure perovskite phase were obtained for all the specimens. The dielectric behavior was examined to investigate the relaxor behavior of each component. It is found that the specimen undoped and modified with 0.1 mol% WO3 nearly behave as normal ferroelectric ceramics, while with the content of WO3 increasing, the degree of relaxor behavior for the composition increases. Thus, B-site substitute WO3 has a strong effect of inducing relaxor behavior of PMN–PT ferroelectric ceramics near morphotropic phase boundary (MPB). [Copyright &y& Elsevier]

Bimodal porous ceramics with high strength have been fabricated by conventional powder metallurgy utilizing artificially cultured diatom frustules (DFs). The effect of sintering temperature on thermal behaviors, phase transition, and pore structures features of DFs‐based porous ceramics is investigated between 800 and 1200°C. The phase evolution of DFs powders is investigated with thermal analysis (DIL and DSC‐TG). Phase transition behaviors analyzed with XRD, Raman, and FT‐IR spectra confirm the transformation of quartz into cristobalite phases occurs under 1050°C. Sintering under 950°C could bind DFs powders tightly into high strength porous ceramics while maintain the multilayer pore structures simultaneously, having porosity of 56.4%, compressive strength of 15.0 MPa and surface area of 50.9 m2/g, respectively. Slit‐shaped microstructures and mesopores (2‐50 nm) are observed in DFs‐based porous ceramics sintered under 1050°C. Collapse and blockage of pore structures as well as partial fusion of DFs particles happened at the temperature of 1100°C, indicating the presence of diminished multilayers and particle agglomeration. [ABSTRACT FROM AUTHOR]

Transparent Lanthanum-modified lead zirconate titanate ceramics (PLZT 7.4/70/30) with low content of excess lead oxide (PbO) were successfully prepared by a novel vacuum/oxygen hot press sintering process. The phase structure, microstructure, electrical properties and electro-optic scattering performance of PLZT ceramics as a function of excess PbO in the starting powders have been studied and analyzed. As a result, these ceramics exhibited an ultra-high optical transmittance (>69.4% at 1064 nm; thickness 1 mm) from visible to near-infrared wavelength. Herein, we significantly reduce the use of PbO as an auxiliary agent for sintering. This puts forward a good route to meet the objectives of environmental protection and sustainable development. [ABSTRACT FROM AUTHOR]

A novel tert-butyl hydroperoxide tetrasubstituted cobalt phthalocyanine (CoPc(OC10H14N)4) was synthesized by the classical phthalonitrile method. Subsequently, the cobalt phthalocyanine (CoPc) was immobilized on the multi-walled carbon nanotubes (MWCNTs) by ultrasonic impregnation method to obtain CoPc(OC10H14N)4/MWCNTs composites. The obtained composites were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM) and diffuse reflectance spectra (DRS) techniques. Using tert-butyl hydroperoxide (TBHP) as an environmentally friendly oxidant, CoPc(OC10H14N)4/MWCNTs composites can be used as effective catalysts for the epoxidation of styrene. The effects of various variables, such as the mass ratio of CoPc(OC10H14N)4/MWCNTs, reaction time, temperature, molar ratio of substrate/oxidant and the amount of catalyst on the catalytic capability were evaluated. The conversion of styrene reached 97.15%, and the epoxidation product achieved the selectivity of 84.44% under the optimal reaction conditions. [ABSTRACT FROM AUTHOR]

In recent years, traditional Chinese medicine has played an important role in the treatment of gastric cancer in China. ZiYinHuaTan (ZYHT) recipe was developed for advanced gastric cancer and had shown its promising value in the clinic. In this study, we explore the effect of ZYHT on gastric cancer in vitro and in vivo. ZYHT can inhibit tumor growth and improve the general condition of mice in subcutaneous transplantation nude mice models of gastric cancer. And ZYHT can also inhibit cell proliferation and blocked the cells in G0/G1 to induce cell apoptosis in HGC27 and MGC803 cells. Then, network pharmacology analysis showed that ZYHT may exert antitumor effect mainly through PI3K/AKT signaling pathway. Furthermore, the expression of PI3K, p-Akt, CyclinD1, and Bcl-2 was detected in vitro and in vivo. The results showed that ZYHT could decrease the expression of PI3K, CyclinD1, and Bcl-2 both in vitro and in vivo. These results suggested that ZYHT could be used as a method for the treatment of developed gastric cancer. [ABSTRACT FROM AUTHOR]

The bipolar and unipolar fatigue property of lead-free piezoelectric solid solution Bi 0.5 Na 0.5 TiO 3 –Bi 0.5 K 0·5 TiO 3 –SrTiO 3 (BNKST) was studied. Under a bipolar electric field of 4 kV/mm at 10 Hz, the remnant and maximum polarization, maximum strain value of all the studied compositions changed less than 2% after 106 bipolar cycles, while the coercive field exhibited different behavior for BNKST composition with different ferroelectric order states. The unipolar fatigue results also indicated that the BNKST with SrTiO 3 concentration of 0.15 had excellent fatigue property after 107 unipolar cycles under 4 kV/mm. The underlying mechanism was discussed. The excellent fatigue property and large strain response make this system suitable for piezoelectric actuator applications. • Bipolar fatigue-free behavior in BNKST ceramics was found. • Unipolar fatigue-free behavior was also found in BNKST0.15 ceramic. • The mechanism for the variation of coercive field was discussed. [ABSTRACT FROM AUTHOR]

Ferroelectric Mn-doped 0.935Bi 0.5 Na 0.5 TiO 3 -0.065BaTiO 3 (MnBNBT) thin films were fabricated on (111)Pt/Ti/SiO 2 /Si substrates via pulsed laser deposition under different oxygen pressures. (100)-preferred orientation and dense films with perovskite structure were grown. The MnBNBT thin film deposited at an optimized oxygen pressure of 25 Pa exhibited a well-defined ferroelectric P - E loop with an average remnant polarization P r of 27 μC/cm2, a coercive field E c of 5.7 kV/mm, and a high relative dielectric constant of 1295. The leakage current characteristics were assessed, demonstrating that the ohmic conduction behaviors and Fowler-Nordheim tunneling were the main mechanisms of the MnBNBT thin films. Piezoelectric force microscopy indicated that the MnBNBT films possessed favorable local piezoelectric responses and multidomain states. The results suggest that the lead-free thin film produced is potentially applicable in ferroelectric and piezoelectric devices. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) layered nanomaterials, including pristine α-zirconium phosphates (ZrP), amine-intercalated organophilic α-zirconium phosphates (OZrP) and organophilic montmorillonite (OMMT), are directly incorporated into linear low density polyethylene (LLDPE) by injection molding. ZrP and OZrP achieve good dispersion in the LLDPE matrices while OMMT forms agglomerations as observed by scanning electron microscope (SEM). The differential scanning calorimetry (DSC) analysis reveals that well-dispersed ZrP and OZrP could act as a nucleating agent to increase crystallinity of LLDPE while the agglomerated OMMT decreases the crystallinity of the polymer matrix. Tensile tests show that the strength and ductility of the LLDPE/ZrP nanocomposites can be enhanced simultaneously, due to the high modulus and parallel alignment along the injection direction for ZrP in matrix. The heat resistance of LLDPE, can also be enhanced by the addition of 2D nanoplatelets, among which ZrP perform the best, showing an increase of ∼16 °C in heat distortion temperature. Image 1 • ZrP are compared with organophilic montmorillonite on reinforcing non-polar LLDPE. • ZrP exhibits a high efficiency in improving the heat resistance of non-polar LLDPE. • ZrP can significantly enhance the strength and ductility of LLDPE simultaneously. [ABSTRACT FROM AUTHOR]

The dielectric functions and lattice vibrations of (0.935‐x)Bi0.5Na0.5TiO3‐0.065BaTiO3‐xSrTiO3 (BNBSTx) ceramics were investigated by temperature‐dependent spectroscopic ellipsometry and Raman scattering. Based on the analysis of dielectric functions with the Tauc‐Lorentz dispersion model, it was found that the band gap and the temperature coefficient increased with the addition of SrTiO3. Moreover, the frequency, intensity and/or full width at half maximum of phonon modes related to Bi and Ti‐localized phonon modes exhibited local maximum/minimum around the depolarization temperature and permittivity‐maximum temperature, which indicated the ongoing structural transformation. In addition, the Sr introduction affected the TiO6 tilting and the off‐center displacement of Ti4+. These results seem to be significant for the enhanced response functions with the addition of SrTiO3 in BNBSTx ceramics. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • High-quality fluorographene nanosheets are fabricated by microwave-assisted liquid phase exfoliation. • The as-prepared fluorographene nanosheets are comprised of no more than four monolayers. • No other side reaction and impurity elements are introduced during the exfoliation process. • Fluorographene nanosheets exhibit excellent thermal stability and remarkable lubrication behavior in oil. Abstract Fluorographene (FG), as an important class of graphene derivatives, has shown great promise in high-performance devices and lubricating materials. However, the large-scale fabrication of high-quality and impurity-free FG nanosheets still remains a main challenge. Herein, a simple liquid-phase exfoliation approach to prepare thin FG nanosheets through the preliminary intercalation of raw graphite fluoride (GrF) particles by N,N-dimethyl formamide molecules, followed by a short-time microwave treatment is reported. Atom force microscopy measurements demonstrate that as-prepared FG nanosheets are comprised of no more than four monolayers after the microwave irradiation. After exfoliation, a small amount of aromatic C C groups in the FG nanosheets are restored, which slightly lowers the F content in FG as compared with the raw GrF. Besides, no other side reaction and impurity elements are introduced during the exfoliation process as revealed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The resultant high-quality FG nanosheets exhibit excellent thermal stability and remarkable lubrication behavior in oil, and thus can be used as a new class of graphene derivatives with the capability of large-scale fabrication for the future device and various other applications. [ABSTRACT FROM AUTHOR]

High-fat diets (HFDs) are a risk factor for colorectal cancer. The present study investigated whether HFDs increase colon cancer metastasis in BALB/c mice. A total of 40 BALB/c mice were divided into four groups, including the tumor, tumor-HFD, HFD and control groups. After 3 weeks, the tumor weights and metastases were observed. The serum levels of triglyceride, total cholesterol, lapin, interleukin-6 (IL-6) and tumor necrosis factor were analyzed using ELISA. The CD34, vascular endothelial growth factor (VEGF) and angiotensin 2 (ANG2) protein and mRNA levels in tumor tissues were analyzed with immunohistochemistry and reverse transcription-polymerase chain reaction. The metastasis frequency increased in the tumor-HFD group. However, there was no difference in the mean tumor weight between the tumor-HFD and tumor groups. The serum cholesterol levels were increased in the tumor-HFD and HFD groups compared with the control group. The levels of serum IL-6 and tumor necrosis factor-α were increased in the tumor-HFD group compared with other groups. The CD34 protein level, and VEGF protein and mRNA levels were increased in the tumor-HFD group compared with the tumor group. No difference was identified between the ANG2 protein and mRNA levels in of the two groups. It was concluded that HFD increased the serum level of cholesterol and cytokines, and potentially induced tumor angiogenesis, promoting transplanted orthotopic colon tumor metastasis in BALB/c mice. [ABSTRACT FROM AUTHOR]

Abstract The pyroelectric and piezoelectric properties of 4 at% Mn-doped Bi 4 Ti 2.9 W 0.1 O 12 (BiTW-Mn) Aurivillius ceramic were investigated and compared to Bi 4 Ti 2.9 W 0.1 O 12 (BiTW) counterpart, which were fabricated using a conventional solid state reaction method. High resistivities of 4.9 × 1012 and 2.5 × 1011 Ω cm at 100 °C were obtained in the W-doped and W/Mn-codoped BiT ceramics, respectively. They showed similar activation energies and ionic- p -type mixed conduction mechanisms. Higher pyroelectric coefficients of 57.1 μC/m2K and piezoelectric coefficients of 21 pC/N, as well as much lower dielectric loss of 0.003 were achieved in W/Mn-codoped ceramics. These property changes were mainly induced by M n Ti − V o defect dipoles. The effect of acceptor doping was evidenced by an internal bias field, shown by a horizontal offset in the polarization-field behavior. The improved properties together with high thermal stability indicate that BiTW-Mn may be a promising candidate for pyroelectric and piezoelectric devices at elevated temperatures. [ABSTRACT FROM AUTHOR]

Abstract In recent years, Chinese medicine has played an important role in the prognosis of gastric cancer. Precancerous lesions of gastric carcinoma (PLGC) is a class of gastric cancer which is closely related to the gastric mucosal pathology changes in the role of carcinogenic incentives, and plays key role in the progression of normal gastric mucosal cells into gastric cancerous cells. In current experiment, we explore the relationship between Chinese traditional medicine (Xiao Tan He Wei Decoction) and gastric cancer in the PLGC rat animal models and epithelial-mesenchymal transitioned GES-1 cells which were induced useing 1- Methyl-3-nitro-1-nitrosoguanidine (MNNG). PLGC rat model showed significant deterioration in the gastric mucosa with terrible growth rate in body weight and more atypical hyperplasia in gastric mucosa. MC cells, MNNG induced GES-1 cells which epithelial- mesenchymal-transition (EMT)-related proteins have a great change compare with normal GES-1 cells. The cells had characteristics of malignant cells including proliferation, invasion and metastasis ability. Our research founds that Xiao Tan He Wei Decoction could inhibit cell proliferation and increased apoptosis by increase the level of pro-apoptotic proteins like Bax and caspase-3 and decreased the level of anti-apoptotic protein Bcl-2, block the cells in G0/G1 phase simultaneously. Furthermore, Xiao Tan He Wei Decoction could inhibit nuclear factor kappa-light-chain-enhancer (NF-kB) activity and inhibit its transfer from the cytoplasm to the nucleus. However, when we incubated with NF-κB activator PMA, the effect of Xiao Tan He Wei Decoction was reversed. These results suggested that Xiao Tan He Wei Decoction could be used as a method for the treatment of gastric precancerous lesions, and possibly provide a theoretical basis for the clinical treatment of gastric cancer and gastric precancerous lesions. [ABSTRACT FROM AUTHOR]

An amphiphilic graft copolymer ( P3 ) composed of poly(oligo (ethylene glycol) methacrylate) (POEGMA) as a hydrophilic segment and a polystyrene (PS) as a hydrophobic chain was prepared. P3 was used to incorporate a highly efficient hydrophobic oxygen probe platinum(II)-5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorophenyl)-porphyrin (PtTFPP) in its micelles to enable the application of PtTFPP in aqueous solution for biosensing. For achieving ratiometric oxygen sensing, a hydrophobic conjugated polymer ( CP ) was used as a fluorescence resonance energy transfer (FRET) donor for PtTFPP - the FRET acceptor. Results showed that diameters of these nano-oxygen sensors ranging from 50 to 60 nm and FRET efficiency as high as 98% could be achieved. Further, FRET contributed to the brightness of PtTFPP in micelles. High quantum yields of PtTFPP in non-FRET micelles and FRET micelles under nitrogen were achieved to be 0.109 and 0.231, respectively. The sensors were found to be able to measure oxygen concentrations from 0.082 to 40.9 mg/L at room temperature with linear Stern-Volmer constants. These sensors were also demonstrated to be suitable for monitoring extracellular oxygen consumption of E. Coli and HeLa cells. This study illustrated a feasible approach to achieve highly efficient ratiometric oxygen sensors without specific structure modification of the efficient PtTFPP probe, however using an amphiphilic graft copolymer approach. [ABSTRACT FROM AUTHOR]

Perovskite nanocrystals (PNCs) have emerged as advanced materials for various applications. Herein, we developed oxygen insensitive PNCs in polymer matrices and applied them as internal reference to achieve ratiometric sensing for oxygen. Significant emission color changes from orange under nitrogen to green under oxygen were observed. Further micro-patterned sensors were prepared by micro/nano-imprint technology. Results showed that all these micro-structures increased sensors’ sensitivity, however, affected sensors response time significantly. The film with pinholes slowed down the response times; the films with pillars shorted the response time. Therefore, for the first time we prepared new PNCs-based ratiometric gaseous oxygen sensing films and further prepared micro-structured sensors. This study may broaden the applications of perovskite materials and also oxygen sensors. [ABSTRACT FROM AUTHOR]

Epoxy composites with excellent toughness and strength have been successfully fabricated by direct incorporation of graphite fluoride (GrF) without using any solvent or surfactant modification. Owing to the strong interfacial interactions, the glass transition temperature of GrF/epoxy composites exhibits a significant improvement as observed by dynamic mechanical analysis. Mechanical characterizations on GrF/epoxy composites suggest that the optimal increase of tensile strength and Young's modulus is achieved at a low filler concentration of 0.5 wt%, which is attributed to the favorable level of the GrF dispersion in the epoxy matrix. A maximum toughening effect is obtained at the concentration of 1 wt% GrF in the epoxy matrix with a 1.5-fold improvement in fracture toughness. The generation of crack pinning and crack deflection in epoxy due to the existence of GrF platelets is proposed to be the main toughening mechanism. Besides, microcracks resulted from pulling out, layer breakage and interfacial debonding of GrF platelets also contribute to the improvement in the fracture toughness of GrF/epoxy composites. [ABSTRACT FROM AUTHOR]

Highly transparent hydrophobic coatings with scratch-resistant property attract tremendous interest from both scientific research and practical applications. The present study demonstrates that hydrophobic coatings with high transmittance and anti-scratch performance on glass substrates can be easily created by dewetted epoxy structures in large scale, followed by the attachment of a low surface energy material. The influence of epoxy solution concentrations on the surface dewetted structures, as well as the hydrophobicity and transmissivity of glass substrates were investigated. It was found that the epoxy solution concentration of 5% combined with a low surface energy material coating on glass exhibited the highest contact angle of ∼113°. UV–vis spectrum studies indicated that the coatings fabricated by our method had almost the same transmittance as that of the glass substrate. In addition, nano-scratch test illustrated that the prepared coating was capable of delaying crack generation, further strengthening the glass surfaces. Furthermore, our approach also facilitates the large-scale fabrication of hydrophobic anti-scratch coatings on glass as demonstrated by the preparation of mobile phone screen coatings. The detailed mechanism of large-scale hydrophobic coatings on glass with high transmission and anti-scratch performance was carefully elaborated. [ABSTRACT FROM AUTHOR]

Boron-doped diamond (BDD) and ZnO are widely used in the fields of electrocatalysis and photocatalysis, respectively. In general, BDDs are used directly as anodes or the bottom electrodes of multilayered films owing to processing difficulties, while ZnO is more often used to fabricate nanostructures because it provides a large specific surface area that is very helpful for enhancing catalytic performance. In this study, a nanoporous (NP) surface was constructed on a BDD film grown on Ta substrate, and ZnO nanorods were grown in situ on the NPBDD to enhance adhesion between the ZnO nanorod layer and the NPBDD surface. The effect of the BDD-surface-pore structure on the growth sizes and morphologies of the ZnO nanorods was studied by analyzing the microstructures, phases, and compositions of the samples. In addition, the photoelectrocatalytic performance of ZnO/NPBDD anodes in aniline degradation was analyzed and compared to that of conventional BDD and NPBDD anodes. The mechanism for the degradation of the ZnO/NPBDD film was analyzed by UV–vis spectroscopy and the ZnO/NPBDD anode was used to rapidly decompose aniline in a photoelectro-Fenton reaction following pH and current optimization. In short, ZnO/NPBDD films are potentially useful photoelectric anodes for the degradation of organic matter. [ABSTRACT FROM AUTHOR]

A novel NiO/carbon nanotube (CNT)/poly(3,4-ethylenedioxythiophene) (PEDOT) composite with a coaxial tubular nanostructure was successfully deposited on a glassy carbon electrode (GCE) through electrochemical processes. The outer PEDOT matrix has a high affinity for biomolecules, while the CNT inner layer has a strong electron-transport capacity. Hence, the NiO/CNT/PEDOT/GCE was used for the simultaneous determination of dopamine (DA), serotonin (5-HT), and tryptophan (Trp). Electrochemical responses of the NiO/CNT/PEDOT/GCE sensor were investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. Three well-separated oxidation peaks were observed in a mixed system containing DA, 5-HT, and Trp; the 5-HT–DA and Trp–5-HT potential separations were 160 and 324 mV, respectively, owing to the synergistic effect of NiO, CNT, and PEDOT. Linear responses were obtained for DA, 5-HT, and Trp in the 0.03–20, 0.3–35, and 1–41 μM concentration ranges, with detection limits of 0.026, 0.063, and 0.210 μM, respectively. In addition, it was possible to simultaneously determine the three analytes using the NiO/CNT/PEDOT composite, which suggests that the sensor has promising applicability. [ABSTRACT FROM AUTHOR]

Polycrystalline boron-doped diamond (BDD) was grown on a Ta substrate by electron-assisted hot filament chemical vapor deposition, and porous BDD/Ta multilayer films were constructed by Ni-nanoparticle-assisted plasma etching. The etching process and the formation mechanism of the porous nanostructure on the BDD were investigated by changing the Ni sputtering time and the BDD etching time. Under optimal etching conditions, differently shaped nanoholes appeared on the different crystal planes of the diamond crystallites, including square and triangular (or hexagonal) holes. In addition, changes in the elemental composition, crystal, and chemical-bonding structures were analyzed; the effective electroactive surface area and charge transfer capability at the liquid-solid interface were found to be improved in the etched crystallites. Therefore, we believe that the electrocatalytic performance of a porous BDD/Ta electrode would also be improved, as electrocatalytic performance is strongly affected by the porous nanostructures of BDD films. The porous BDD/Ta electrode acted as the anode for the rapid degradation of methylene blue through the electro-Fenton process. [ABSTRACT FROM AUTHOR]

Abstract: The pyroelectric properties of Mn‐doped Aurivillius ceramics with different pseudo‐perovskite layers were investigated. The pyroelectric coefficients for 0.2 wt% Mn‐doped two‐layer CaBi2Nb2O9 (CBN–Mn), three‐layer Bi4Ti2.85Nb0.15O12 (BTN–Mn), and four‐layer CaBi4Ti3.95Nb0.05O15 (CBTN–Mn) ferroelectric ceramics were found to be on the order of 26.0, 54.4, 84.4 μC/m2K at room temperature, respectively. These values were closely associated with the number of octahedral layers in the pseudo‐perovskite blocks. The high pyroelectric coefficient, together with low dielectric permittivity and loss (tan δ < 0.003), results in to high figures of merit for the current responsivity, voltage responsivity, and detectivity. The excellent pyroelectric properties and high Curie temperatures (TC > 660°C) make the Aurivillius ceramics potential candidates for pyroelectric devices over a broad temperature range. [ABSTRACT FROM AUTHOR]

In present work, a multifunctional piezoelectric/photoluminescence effect, which originated from the combination of the piezoelectric properties and the photoluminescence effect, was realized in one-dimensional Er 3 + doped lead-free BaTiO 3 nanofibers prepared by a sol-gel based electrospinning method. The X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) were utilized to characterize the morphologies and phase structures. The effect of the host crystallization and rare-earth concentration on the structure and photoluminescence properties was studied. In addition, temperature-dependent PL spectrum exhibited a piezoelectric/photoluminescence coupling effect, characterized by the enhanced photoluminescence intensity around the ferroelectric-paraelectric phase transition temperature of BaTiO 3 . [ABSTRACT FROM AUTHOR]

In this paper, the surface of polytetrafluoroethylene (PTFE) was modified by 1 MeV proton beam at high temperature. The changes of wear resistance and hardness of PTFE before and after irradiation were evaluated by ball/pin disk friction loss tester and nanoindentation tester, respectively. The results showed that the wear resistance of PTFE irradiated by proton at high temperature has been significantly enhanced. The mass wear rate decreases from 2.75 × 10−6 g/Nm to 0.39 × 10−6 g/Nm, and the wear depth decreases from 29.9 μm to 8.2 μm, respectively. Proton irradiation could be a simple and effective method for PTFE surface modification and can significantly improve the wear resistance. The potential chemical reaction mechanism for the improvement of wear resistance of irradiated PTFE in terms of microstructure was discussed. Crosslinking induced by proton irradiation enhanced the interaction force among PTFE molecules, thus the mechanical properties were improved. [Display omitted] • This study used gradient energy proton beams to irradiate PTFE at high temperature. The cross-linking reaction changes originally highly linear molecular structure into a network structure. The structural transformation has improved wear resistance and hardness. • This study used ATR-FTIR, XRD, LRS, XPS, SEM to characterize the surface morphology and chemical structure changes of PTFE before and after irradiation, confirming that irradiation induced a series of chemical reactions. • This study discusses the possible chemical reaction mechanisms that may occur after irradiation. The entanglement of cross-linked molecules enhances intermolecular forces, thereby improving friction resistance and hardness. [ABSTRACT FROM AUTHOR]

• Thermal energy storage coatings fabricated using diatom frustules (DFs) and wax. • Ag nanoparticle decorated DFs (Ag-DFs) prepared by electroless silver plating. • Ag-DF increase the thermal conductivity of the coating to 0.87 W/m·K. • Micro/nanostructured DF and low-surface-energy wax achieve superhydrophobicity. Solid-liquid phase change materials (PCMs) provide an eco-friendly and cost-effective solution for waste heat recovery and thermal management. However, leakage and low thermal conductivity are two long-standing bottlenecks for their large-scale application. Applying a synthesized multi-level porous scaffold to prepare shape-stabilized PCMs (ss-PCMs) is an efficient, but high-cost strategy used to address the above problem. Herein, a strategy for fabricating enhanced thermally conductive ss-PCM coatings has been developed using artificially cultured, hierarchically porous Ag nanoparticle decorated diatom frustules (Ag-DFs) utilizing a facile spray-coating method. The delicate pores and high specific surface area (101.78 m2/g) endow the Ag-DFs to adsorb 55 wt% of paraffin wax (PW) without leakage, thereby exhibiting a melting enthalpy of 114.27 J/g. The corresponding ss-PCM coatings demonstrate a thermal conductivity of 0.87 W/m·K, which is ∼ 2.95-fold higher than pure PW. In addition, the abundant micro/nanoscale texture in the Ag-DFs along with the low-surface-energy of PW synergistically produce superhydrophobicity in the coating, thereby improving its ability to resist external environmental impacts, extending the service life. With high energy storage density, enhanced thermal conductivity, and good scalability, our superhydrophobic ss-PCM coating should find potential use in energy-saving building materials and thermal management of electrical devices, as well as self-cleaning surfaces. [ABSTRACT FROM AUTHOR]

A porous boron-doped diamond (PBDD)/Ta sensing electrode was prepared for the fast, sensitive, stable, and discriminative detection of dopamine (DA) and pyridoxine (vitamin B6) in human serum. All the exposed surfaces of the diamond grains of the BDD layer were etched into a porous form, with pore sizes of less than 500 nm and an average depth of about 200 nm. The electrochemical performance characteristics of the PBDD layer and the reaction mechanisms enabling the detection of DA and vitamin B6 were studied. Large numbers of oxygen-containing groups on the PBDD surface, as well as the activity difference of the different planes, enabled us to successfully distinguish between DA and B6 by using the PBDD/Ta electrode. The low background current of PBDD, the large active area of the porous surface, and the high electron transfer properties led to the PBDD electrode having a high sensitivity. Therefore, this sensor can be used to stably detect DA and B6 in serum. Aberrant levels of DA and vitamin B6 in body fluids are key risk indicators for some diseases; thus, monitoring the levels of both and other species in serum is of great significance to clinical diagnoses. [ABSTRACT FROM AUTHOR]

In this paper, we describe a method for fabricating dry electrodes for use in recording electroencephalograms (EEGs), which are based on the use of chitosan (Ch), gold (Au) particles, and titanium dioxide (TiO 2 ) nanotube arrays deposited on titanium (Ti) thin sheets. The samples were characterized by scanning electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy, and EEG signal collection. The TiO 2 nanotube arrays were grown on the Ti thin sheet by an electrochemical anodic oxidation method. The Au particles were deposited on the bottom and surface layers of the TiO 2 nanotube array using an electrochemistry-based multi-potential step technology. The fabricated dry Ch/Au-TiO 2 electrodes have an efficient conversion interface for ion current/electron current, a high biocompatible contact surface, and a fast electron transfer channel. To confirm that the Ch/Au-TiO 2 layer can be used in dry EEG electrodes, the impedance spectra of the electrodes in solution and skin were analyzed. The mean impedance values for skin were found to be approximately 169 ± 33.0 kΩ at 2.15 Hz and 67.4 ± 8.9 kΩ at 100 Hz. In addition, EEG signals from the forehead and sites with hair were collected using both the dry Ch/Au-TiO 2 electrode and a wet Ag/AgCl electrode for comparison purposes. It was found that high quality EEG signal recordings could be obtained using the dry electrodes. The fact that electrolytes are not required means that the electrodes are suitable for use in long-term bio-potential testing. [ABSTRACT FROM AUTHOR]

A graft copolymer composed of poly( ε -caprolactone) as a hydrophobic chain and poly( N -(2-hydroxypropyl)methacrylamide) as a hydrophilic segment with an internal reference probe for oxygen sensing was prepared. Highly efficient platinum(II)meso-tetra(pentafluorophenyl)porphine (PtTFPP) was used as a typical oxygen probe. Although PtTFPP was highly efficient, it is hydrophobic, limiting its direct application for oxygen sensing in biological conditions. By using the amphiphilic graft copolymer, PTTFPP was successfully incorporated into the micelles formed by this polymer to not only enable the application of PtTFPP for biosensing in medium but also retain its high efficiency. The quantum efficiency of PtTFPP in the micelle solution under nitrogen can reach as high as 0.20. The PtTFPP-containing micelles were tested for high throughput cell respiration and bacteria detection. The influence of an antibiotic, antimycin as a representative example, on cell respiration was also studied. For achieving high accurate sensing, an internal built-in reference probe with aggregation induced emission properties were also polymerized in the graft copolymer. This study demonstrated that the graft polymer approach is a good way to enable highly efficient and hydrophobic oxygen probes for biosensing. [ABSTRACT FROM AUTHOR]