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Carbon nanotubes (CNTs)/carbon fiber (CF) reinforcements were synthesized under different catalyst compositions and reduction conditions. The effects of the catalyst, reduction temperature and reduction time on the surface morphology, graphitization, and single filament tensile strength of the prepared CNTs/CF samples were investigated. When nickel was used as the catalyst and copper as the catalyst promoter, with the increase of copper concentration, the catalytic activity increased. Thus, the carbon source was consumed more completely, improving the abundance of CNTs with good graphitization. And the effect of repairing CF defects was more obvious, hence the single filament tensile strength accordingly increased. Besides, the increase of catalyst reduction temperature and reduction time intensified the etching of CF by catalyst, and decreased the single filament tensile strength of CF. With the deposition of CNTs, the tensile strength of CF was enhanced in varying degrees. When the concentration of cooper was 0.01 mol/L with the reduction time of 10 min and reduction temperature of 450 °C, CNTs/CF had the highest tensile strength, which can reach up to 4.51 GPa. We determined that bimetallic catalysts could adjust the catalytic activity of nickel. The change of reduction time and temperature would affect the quality of CNTs, which was helpful to obtain high quality CNTs on CF surface and improve the mechanical properties of CNTs/CF and its composites. [ABSTRACT FROM AUTHOR]

Using chemoproteomic techniques, we first identified EIF2AK2, eEF1A1, PRDX3 and VPS4B as direct targets of berberine (BBR) for its synergistically anti-inflammatory effects. Of them, BBR has the strongest affinity with EIF2AK2 via two ionic bonds, and regulates several key inflammatory pathways through EIF2AK2, indicating the dominant role of EIF2AK2. Also, BBR could subtly inhibit the dimerization of EIF2AK2, rather than its enzyme activity, to selectively modulate its downstream pathways including JNK, NF- κ B, AKT and NLRP3, with an advantage of good safety profile. In EIF2AK2 gene knockdown mice, the inhibitory IL-1 β , IL-6, IL-18 and TNF- α secretion of BBR was obviously attenuated, confirming an EIF2AK2-dependent anti-inflammatory efficacy. The results highlight the BBR's network mechanism on anti-inflammatory effects in which EIF2AK2 is a key target, and inhibition of EIF2AK2 dimerization has a potential to be a therapeutic strategy against inflammation-related disorders. EIF2AK2 is proved to be a key target for BBR's network mechanism, and inhibition of EIF2AK2 dimerization has a potential to be a therapeutic strategy against inflammation-related disorders. [Display omitted] [ABSTRACT FROM AUTHOR]

Highly efficient and multifunctional electromagnetic wave (EMW) absorbers which can be easily processed are desirably required. Herein, cupric ammonia is creatively adopted as the catalyst precursor of the in-situ growth of carbon nanotubes (CNTs) onto carbon fiber (CF) during chemical vapor deposition. Typically, when prepared at 750 °C, N/S co-doped bamboo-like amorphous CNTs/CF was successfully synthesized, while some Cu nanoparticles were remained in CNT forests. The sample obtains an excellent absorption toward EMWs, demonstrating a minimal reflection loss of −59.28 dB at 14.1 GHz with an ultrathin thickness of 1.42 mm. Concurrently, it is over a relatively broad effective absorption bandwidth (EAB) of 3.3 GHz (12.3–15.6 GHz) with 31% loading in the paraffin matrix. And the EAB value of CA-700 reaches 3.7 GHz (14.3–18 GHz) at merely 1.45 mm. The satisfying attenuation performance mainly originates from the synergistic effects of continuous three-dimensional conducting networks, abundant interfaces, sufficient defects, and the well impedance matching. Moreover, all as-prepared samples could be potentially used as reinforcements of resin matrix composites with high strength. Therefore, a facile route is provided to produce thin, lightweight, superior and high-strength EMW absorbing materials based on CF and CNTs. [ABSTRACT FROM AUTHOR]

• The receiver's 6-DOF model, considering the influence of multiwind disturbances and time-varying mass, are established. • The affine nonlinear form of 6-DOF nonlinear model is formulated to facilitate the design of nonlinear controllers. • Fixed-time extended state observers (FTESOs) are designed for each control loop to estimate the lumped disturbances. • A backstepping-based predefined-time anti-disturbance control (PTADC) framework including five subcontrollers is proposed. • The anti-disturbance and predefined-time stable performance of PTADC in a multi-loop system is proved. Aiming at the relative position-holding and velocity-holding control problems during the refueling phase of autonomous aerial refueling (ARR) missions, this paper proposes a predefined-time anti-disturbance control (PTADC) structure for receiver aircraft. First, a 6-degree-of-freedom (6-DOF) rigid model of the receiver in the refueling phase is established, with the time-varying mass, time-varying inertia, time-varying unbalanced moment, multiwind disturbances, and model uncertainties explicitly considered. Moreover, to facilitate the design of a nonlinear controller, the affine nonlinear form of the 6-DOF receiver model is formulated. Then, fixed-time extended state observers (FTESOs) are designed for each subsystem to estimate the lumped disturbances. By compensating for these estimated lumped disturbances, a backstepping-based PTADC structure with disturbance resistance and predefined-time convergence is developed to complete the refueling task. The performance of the entire closed-loop system is rigorously proven through Lyapunov functions. Finally, the effectiveness of the proposed refueling control framework is validated through numerical simulations. [ABSTRACT FROM AUTHOR]

Carbon fiber (CF) has rarely been presented as a promising electromagnetic wave (EMW) absorber because of its excessive electrical conductivity. Herein, the continuous preparation of carbon nanotubes/carbon fiber (CNTs/CF) multiscale reinforcements and microwave absorbers was realized by one-step chemical vapor deposition (CVD) at different temperatures. Beneficial from the intertwined CNTs, good graphitization and crystallinity, and satisfactory epoxy resin wettability, CNTs/CF650 and its composites show excellent tensile, interfacial and interlaminar shear strength. Importantly, CNTs/CF650 obtains a high-performance EMW absorption ability with a minimum reflection loss (RL min) of −56.11 dB at 7.36 GHz, and delivers an effective absorption band (EAB) of 3.6 GHz at an ultrathin thickness of 1.18 mm. Notably, CNTs/CF700 exhibits the widest EAB (4.2 GHz) at merely 1.35 mm, basically covering the entire Ku-band. The superior RL min and boosted EAB stem from the synergistic effects of multiple heterointerfaces, enriched defects, proper electronic conductivity, and rational impedance matching. Therefore, the work demonstrates a facile and efficient strategy to develop strong EMW absorbers based on CF with light weight, thin thickness, and high strength. [Display omitted] [ABSTRACT FROM AUTHOR]

MXenes have been attracting enormous attention owning to their high electronic conductivity, abundant functional groups, and surface modification ability in the application of electromagnetic interference (EMI) shielding. In this work, TiO 2 nanoparticles were in-situ grown on the surface of crumpled Ti 3 C 2 T x MXene to generate TiO 2 /MXene heterointerfaces and create an extra absorption path. It was found that Ti 3 C 2 T x with less oxidation time generated more TiO 2. This intriguing phenomenon was caused by the fact that more functional groups escaped in the pre-oxidation step, creating extra active sites and allowing for more intense oxidation in a shorter period. Besides, the hybrid showed negative permittivity due to the metal-like conduction behavior, contributing to the reflection-dominant shielding mechanism. The TiO 2 /MXene heterostructure with negative permittivity exhibited an excellent total EMI shielding effectiveness of 73.98 dB at a filler content of 25 wt% in 8.0–12.4 GHz (covering the X band) at 2 mm. This work offers a new insight into exploring the structure-property relationship for MXene-based materials. [ABSTRACT FROM AUTHOR]

• A fundamental framework consisting of the IFDS-based path planning module and the BLADRC-based path tracking module is developed. • A long short-term memory (LSTM)-based fast online decision-making network matched with the IFDS is designed. • The trained LSTM network can quickly provide the optimal coefficients for the IFDS. • The dynamic characteristics of the 6-DOF UAV model and the performance of the inner controller are considered in the planning phase so that the planned path has high feasibility. • The proposed method is competent for 3D static and dynamic environments with high real-time performance, and planned path has high quality and feasibility. Path planning is crucial for achieving autonomous and safe flight of fixed-wing unmanned aerial vehicles (UAVs). The existing methods generally cannot simultaneously balance real-time performance, near optimality, and feasibility in three-dimensional obstacle environments. To this end, this paper proposes a deep learning-based integrated path planning and tracking control framework for obstacle avoidance. First, a fundamental framework, including an interfered fluid dynamical system (IFDS)-based path planning module and a backstepping control-based path tracking module, is established. Then, to satisfy high real-time requirements, a long short-term memory (LSTM)-based fast online decision-making network matched with the IFDS is developed. Extensive training samples are generated by the fundamental framework, and receding horizon control is employed to optimize these samples so that the LSTM can provide near-optimal coefficients for the IFDS. Furthermore, the dynamic characteristics of an actual UAV system and the performance of the tracking controller are fully considered during sample generation, enabling that the paths planned by the LSTM-assisted IFDS are highly feasible. Finally, the results of numerical simulations and hardware-in-the-loop experiments show that our method can plan near-optimal obstacle-free paths with high feasibility in real-time. [ABSTRACT FROM AUTHOR]

MXenes have been utilized to fabricate electromagnetic wave (EMW) absorbers owning to large aspect ratio, high electronic conductivity, and favorable hydrophilicity. In this work, the core-shell MXene/nitrogen-doped (N-doped) C heterostructure was firstly prepared via HCl and LiF etching, in-situ polymerization, and carbonization. When mixed with paraffin at a low filler loading of 30 wt%, the MXene/N-doped C hybrid reached a wide effective absorption bandwidth of 5.0 GHz (13.0 GHz–18.0 GHz) at a thin thickness of 1.72 mm. The stronger ability of attenuating EMWs promoted the absorption performance of MXene/N-doped C, overcoming the deficiency in the characteristics of impedance compared with its counterparts. This work provides a new insight in manufacturing MXene-based absorbers to alleviate EMW pollution by delicate structural design and effective multi-component strategy. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs)/carbon fiber (CF) reinforcements were prepared by chemical vapor deposition after electrochemical anodization and catalyst impregnation. The results showed that after the electrochemical anodization, the CFs were oxidatively etched and the surface roughness increased, which is helpful to form a uniform catalyst coating on the surface of CF. Under the current of 0.4 A and 0.6 A, CNTs can grow evenly on the surface of CF. Within a certain range, with the increase of growth time, the density and length of CNTs are improved. The CNTs/CF reinforcement prepared at the current intensity of 0.4 A and the growth time of 8 min has the best comprehensive performances compared with other as-fabricated samples. The tensile strength of the sample can reach a high value of 4.56 GPa, and the wettability of resin has an effective improvement. [ABSTRACT FROM AUTHOR]

The emergence and spread of vancomycin-resistant enterococci (VRE) have posed a significant challenge to clinical treatment, underscoring the need to develop novel strategies. As therapeutic options for VRE are limited, discovering vancomycin enhancer is a feasible way of combating VRE. Gambogic acid (GA) is a natural product derived from the resin of Garcinia hanburyi Hook.f. (Clusiaceae), which possesses antibacterial activity. This study aimed to investigate the potential of GA as an adjuvant to restore the susceptibility of VRE to vancomycin. In vitro antibacterial and synergistic activities were evaluated against vancomycin-susceptible and resistant strains by the broth microdilution method for the Minimal Inhibitory Concentrations (MICs) determination, and checkerboard assay and time-kill curve analysis for synergy evaluation. In vivo study was conducted on a mouse multi-organ infection model. The underlying antibacterial mechanism of GA was also explored. GA showed a potent in vitro activity against all tested strains, with MICs ranging from 2 to 4 μg/ml. The combination of GA and vancomycin exhibited a synergistic effect against 18 out of 23 tested VRE strains, with a median fractional inhibitory concentration index (FICI) of 0.254, and demonstrated a synergistic effect in the time-kill assay. The combination therapy exhibited a significant reduction in tissue bacterial load compared with either compound used alone. GA strongly binds to the ParE subunit of topoisomerase IV, a bacterial type II DNA topoisomerase, and suppresses its activity. The study suggests that GA has a significant antibacterial activity against enterococci, and sub-MIC concentrations of GA can restore the activity of vancomycin against VRE in vitro and in vivo. These findings indicate that GA has the potential to be a new antibacterial adjuvant to vancomycin in the treatment of infections caused by VRE. [Display omitted] [ABSTRACT FROM AUTHOR]

The potential of two-dimensional layered MXenes in electromagnetic wave (EMW) absorption needs further development. Herein, we carried out the in situ growth of carbon nanotubes (CNTs) on the surface of Ti 3 C 2 T x MXene at ultra-low temperature via chemical vapor deposition. The obtained CNTs exhibited a bamboo-like structure and were accompanied by helical carbon nanofibers. The ultra-low temperature solved the problem that the high temperature required in the traditional CNT growth process would destroy the structural integrity of MXene. The lush CNT forest cross-linked the MXene layers, transforming the two-dimensional layered structure into a three-dimensional conductive network, providing abundant conductive channels for carriers, optimizing the impedance matching of the CNT/MXene hybrid, and resulting in a significant dielectric loss. The as-prepared CNT/MXene hybrid exhibited a minimal reflection loss of −52.56 dB (99.9994% EMW absorption) in the X-band. This work proposes a new idea to enhance the EMW absorption properties of Ti 3 C 2 T x MXene and fabricate high-performance MXene-based EMW absorbers. [ABSTRACT FROM AUTHOR]

As electromagnetic wave (EMW) pollution has become a serious problem in daily life, lightweight, efficient, and mass-produced EMW-absorbing materials are urgently needed. Herein, we developed a novel method for the continuous growth of carbon nanotubes (CNTs) on the surface of polyacrylonitrile (PAN)-based carbon fibers (CFs) by chemical vapor deposition (CVD), which can be applied to mass production. The obtained CF/CNT composites demonstrate outstanding EMW absorption capability, exhibiting a -58.75 dB reflection loss (RL) at a thickness of 1.54 mm. An effective absorption bandwidth (RL < -10 dB) of 4.24 GHz (13.76–18.00 GHz) was achieved at a thickness as low as 1.25 mm, which almost covers the entire Ku band. The excellent EMW-absorbing performance can be attributed to the 3D conductive network constructed by the CNT forest, which effectively promotes multiple reflections and scattering, and further favors dipole and interface polarizations. The mechanical properties of CF, CF-electrochemical anodic oxidation (EAO), and CF/CNT composites were examined, the results showed that the single-filament tensile strength of CF/CNT@0.07 and CF/CNT@0.09 was effectively improved. Our work suggests that the novel CF/CNT composite is a promising material for EMW absorption and strength enhancement owing to its light weight, high strength, low thickness, and good scale-up ability. [Display omitted] [ABSTRACT FROM AUTHOR]

Accurate detection of saliva glucose levels is crucail for diagnosing diabetes and oral diseases. However, the complex bacterial environment in the oral cavity presents challenges, particularly in reducing sensor sensitivity due to bacterial adhesion. The excellent self-cleaning capabilities of super-hydrophilic materials make them one of the top choices. To surpass the limitations of traditional super-hydrophilic materials, a Spin coating-Plasma treatment-Coprecipitation treatment (SPC) strategy was implemented to develop a super-hydrophilic gel saliva glucose sensor. Surface-initiated polymerization was used to form phenylboric acid hydrogels for glucose binding. A spin-coated transition layer protects the hydrogel, while plasma treatment and co-precipitation methods create a super-hydrophilic surface, providing antibacterial properties. The sensor demonstrated a remarkable ability to reduced bacterial adhesion of the five oral pathogenic bacteria by over 95 %, and significantly inhibited biofilm formation of Streptococcus pneumoniae and Streptococcus mitis by 95.7 % and 96.7 %, respectively. Its detection limit of 3.04 mg/L meets the requirements for saliva glucose detection. Overall, the development of this super-hydrophilic gel sensor holds great promise for wearable oral monitoring devices, offering new opportunities in healthcare managing and monitoring. [Display omitted] • An ultra-antifouling superhydrophilic gel saliva glucose sensor was synthesized through a simple three-step method. • The sensor demonstrates superb resistance to the adhesion of oral pathogenic bacteria. • The effect of the sensor on the growth of biofilm of oral glucose-sensitive bacteria was studied. • The sensor exhibits excellent sensitivity to saliva glucose. • The successful construction of the sensor is expected to be used as a monitorable device for long-term saliva glucose detection. [ABSTRACT FROM AUTHOR]

This article provides a method for growing carbon nanotubes(CNTs) on carbon fibers(CFs) using iron and nickel as catalysts at low temperatures. This series of experiments was conducted in a vacuum chemical vapor deposition(CVD)furnace. It is found that Fe–Ni catalysts, which have a certain thickness and can be better combined with resins when manufacturing composite materials, are more ideal for the growth of CNTs than single metal catalysts. At the same time, it is proved that the CVD process worked best at 450 °C. The mechanical property test proved the reinforcing effect of CNTs on carbon fiber, the single-filament tensile strength of CFs obtained by using Fe–Ni catalyst at 450 °C was 11% higher than that of Desized CFs. The bonding strength of carbon fiber and resin has also been significantly improved. When synthesized at low temperature, CNTs exhibited a hollow multi-wall structure. [ABSTRACT FROM AUTHOR]

Graphene (GN) is transformed into carboxylic graphene (GO-COOH) with carboxylic groups by acidizing. Carboxylic graphene/polyimide (GO-COOH/PI) composite films are prepared by in-situ polymerization. The composite films show strong intermolecular force compared to the PI films which leads to excellent tensile strength and thermal conductivity. The composite films can be transformed into carbon films and graphite films by carbonization and graphitization. The GO-COOH can induce the graphitization process and compensate the defects. The thermal conductivity of graphite films prepared by composite films graphitized at the same temperature is higher compared to that of PI films. The addition of GO-COOH has great effects on reducing carbonization and graphitization temperature and improving property of films. The graphite films treated with 2500 °C possess smoother surface and the color of graphite films turn into dark grey. The films can keep the integral state and bend to a certain extent which exhibits that the flexibility of the graphite films is improved. The thermal conductivity of graphite films prepared by composite films treated with 2500 °C is 760.386 W/mK and increases by 128% compared to that prepared by the PI films, which is suitable for the application of heat conduction. [ABSTRACT FROM AUTHOR]

Carbon films prepared by polyimide (PI) films treated under 1500°C exhibit favorable thermal conductivity. However, the bonds of carbon films will fracture and recombine which will cause shrinking and forming defects. The flexibility of the carbon films will be greatly reduced, and then affect the application of the carbon films in the field of thermal conduction. When the films prepared by the graphene oxide/polyimide (GO/PI) composite films and the reduced graphene oxide/polyimide (rGO/PI) composite films, respectively, rGO and GO can fill the defects, then increasing the flexibility of the carbon films and inducing the carbonation process. Because of the high thermal conductivity and the six-membered ring structure of rGO and GO, the carbonization temperature will decrease and save costs. When the composite films treated under 1500°C, the thermal conductivity increases with the content of rGO and GO. There are connections between PI and graphene. As the amount of rGO and GO increases, the strong interactions between the rGO or GO and PI lead to contact that enhances its thermal conductivity. However, the rGO and GO have different effects on the films flexibility and thermal conductivity and the differences will be described in the article. [ABSTRACT FROM AUTHOR]

Exploring carbon materials is promising for innovative electromagnetic wave (EMW) absorption materials, nevertheless challenged by balancing efficient EMW absorption and continuous large-scale fabrication. In this work, CNTs/CNFs@CF with inimitable 3D network hierarchical structures are fabricated as EMW absorbers via the chemical vapor deposition method. Through detailed characterization of its morphology, structure, composition, and magnetic properties, the material obtained optimal electromagnetism parameters and showed exceptional EMW absorption performance. Herein, the minimum reflection loss (RL min) was −66.00 dB at 1.00 mm and the maximum effective absorption bandwidth of 4.48 GHz was obtained at 1.29 mm. In addition, good mechanical properties with a single-filament tensile strength of 4.99 GPa were achieved, thereby expanding the range of applications. Undoubtedly, CNTs/CNFs@CF realizes the synergy of multiple synergistic loss mechanisms and impedance matching for EMW absorption. In summary, this implies a good prospect for the continuous large-scale preparation of ultrathin and efficient EMW absorbers. • CNTs/CNFs@CF with 3D network hierarchical structures are fabricated for facile synthesis. • The synergistic effect of impedance matching and strong attenuation is realized. • Combined with excellent mechanical properties, expanding the range of applications. [ABSTRACT FROM AUTHOR]

Twenty-six novel tricyclic sophoridinic and matrinic derivatives containing a common chlorinated benzene fragment were designed, synthesized and evaluated for their anti-ebolavirus (EBOV) activities. Structure activity relationship analysis indicated: (i) 12 N -dichlorobenzyl motif was beneficial for the activity; (ii) the chiral configuration at C5 atom might not affect the activity much. Among the target compounds, compound 7d exhibited the most potent potency against EBOV with an IC 50 value of 5.29 μmol/L and an SI value of over 37.8. Further in vivo anti-EBOV assay of 7d identified its high effectiveness, and in vivo anti-MARV assay of 7d suggested its inspiring broad-spectrum anti-filovirus activity. The results provided powerful information on further strategic optimization and development of this kind of compounds against filoviruses. [ABSTRACT FROM AUTHOR]

A novel process has been successfully developed to grow carbon nanotubes (CNTs) on continuously moving carbon fibers (CF) surface by a unique open-ended chemical vapor deposition (CVD) furnace. Systematic researches were carried out under various deposition temperatures, velocities of continuous carbon fibers and catalyst concentrations. The morphologies and structures of CNTs were investigated by field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM), which indicated clearly that carbon fibers with uniformly distributed CNTs were achieved, with the optimum parameters of 650 °C deposition temperature and 6 cm min −1 velocity of continuous carbon fibers and 0.05 M catalyst concentration, respectively. By means of the single fiber push-out tests, the interfacial shear strength (IFSS) of carbon fibers growing CNTs was increased significantly by 84.4% compared to the desized carbon fibers. Furthermore, the results of single fiber tensile test verified that there is scarcely any degradation in the mechanical properties of carbon fibers after the growth of CNTs with the optimum parameters. This study provides a new and original vision for scalable manufacturing of CNTs on continuous moving substrate, when compared to the traditional batch process. [ABSTRACT FROM AUTHOR]

Poly (glycerol sebacate) (PGS), a tough elastomer, has been widely explored in tissue engineering due to the desirable mechanical properties and biocompatibility. However, the complex curing procedure (high temperature and vacuum) and limited hydrophilicity (∼90° of wetting angle) greatly impede its functionalities. To address these challenges, a urethane-based low-temperature setting, PEGylated PGS bioelastomer was developed with and without solvent. By simultaneously tailoring PEG and hexamethylene diisocyanate (HDI) contents, the elastomers X-P-mUs (X referred to the PEG content and m referred to HDI content) with a broad ranging mechanical properties and customized hydrophilicity were constructed. The X-P-mUs synthesized exhibited adjustable tensile Young’s modulus, ultimate tensile strength and elongation at break in the range of 1.0 MPa–14.2 MPa, 0.3 MPa–7.6 MPa and 53.6%–272.8%, with the water contact angle varying from 28.6° to 71.5°, respectively. Accordingly, these elastomers showed favorable biocompatibility in vitro and mild host response in vivo . Furthermore, the potential applications of X-P-mU elastomers prepared with solvent-base and solvent-free techniques in biomedical fields were investigated. The results showed that these X-P-mU elastomers with high molding capacity at mild temperature could be easily fabricated into various shapes, used as reinforcement for fragile materials, and controllable delivery of drugs and proteins with excellent bioactivity, demonstrating that the X-P-mU elastomers could be tailored as potential building blocks for diverse applications in biomedical research. Statement of Significance Poly(glycerol sebacate) (PGS), a tough biodegradable elastomer, has received great attentions in biomedical field. But the complex curing procedure and limited hydrophilicity greatly hamper its functionality. Herein, a urethane-based low-temperature setting, PEGylated PGS (PEGS-U) bioelastomer with highly-customized mechanical properties, hydrophilicity and biodegradability was first explored. The synthesized PEGS-U showed favorable biocompatibility both in vitro and in vivo . Furthermore, the PEGS-U elastomer could be easily fabricated into various shapes, used as reinforcement for fragile materials, and controllable delivery of drugs and proteins with excellent bioactivity. This versatile, user-tunable bioelastomers should be a promising biomaterials for biomedical applications. [ABSTRACT FROM AUTHOR]

The rapid development of organometal halide perovskite solar cells (PSCs) has led to reports of power conversion efficiencies of over 22%. TiO 2 is the most commonly used material for the electron transport layer in PSCs. ZnO is an excellent inorganic semiconductor material owing to its large surface area, easy synthesis, direct electron pathways, large variety of synthesizable nanostructures, and low cost of fabrication. It can potentially replace TiO 2 as the electron transport layer material in high efficiency perovskite solar cells based on flexible substrates. However, the number of reported high performance PSCs using ZnO nanostructures is still limited. This review focuses on the recent developments in the application of ZnO nanostructures in PSCs. The current state-of-the-art techniques and the open questions in the area of ZnO-based PSCs are also highlighted. Finally, we present a brief analysis on the opportunities and challenges for the use of ZnO in PSCs. [ABSTRACT FROM AUTHOR]

An innovative technique has been developed to obtain the uniform catalyst coating on continuously moving carbon fibers. Carbon nanotube (CNT)-grafted carbon fibers with significantly improved tensile strength have been succeeded to produce by using chemical vapor deposition (CVD) when compared to the tensile strength of untreated carbon fibers. The critical requirements for preparation of CNT-grafted carbon fibers with high tensile strength have been found, mainly including (i) the obtainment of uniform coating of catalyst particles with small particle size, (ii) the low catalyst-induced and mechano-chemical degradation of carbon fibers, and (iii) the high catalyst activity which could facilitate the healing and strengthening of carbon fibers during the growth of CNTs. The optimum growth temperature was found to be about 500 °C, and the optimum catalyst is Ni due to its highest activity, there is a pronounced increase of 10% in tensile strength of carbon fibers after CNT growth at 500 °C by using Ni catalyst. Based on the observation from HRTEM images, a healing and crosslink model of neighboring carbon crystals by CNTs has been formulated to reveal the main reason that causes an increase in tensile strength of carbon fibers after the growth of CNTs. Such results have provided the theoretical and experimental foundation for the large-scale preparation of CNT-grafted carbon fibers with the improved tensile strength, significantly promoting the development of CNT-grafted carbon fiber reinforced polymer composites. [ABSTRACT FROM AUTHOR]

Abstract: Tuberculosis is a serious threat to public health throughout the world. A series of new 13-n-nonylprotoberberine derivatives was designed, synthesized and evaluated for anti-mycobacterial activity against Mycobacterium tuberculosis strain H37Rv. Several compounds (2, 11a-c, 11g, 13d, 15c) exhibited excellent anti-tubercular activity with an MIC below 1.0μg/mL. Notably, compound 13d showed potential antibacterial effect against both drug-susceptible and multidrug-resistant (MDR) M. tuberculosis with MIC ranges of 0.0625–1.0μg/mL. These results suggest a mode of action different from that of the current anti-mycobacterial drugs rifampicin and isoniazid. Hence, compound 13d is an attractive lead compound for the development of new antitubercular agents. [Copyright &y& Elsevier]

Abstract: Tuberculosis (TB) is a disease which kills two million people every year and infects over one-third of the world′s population. Eighteen new 8-substituted berberine derivatives were synthesized and evaluated for their anti-mycobacterial activities against Mycobacterium tuberculosis (M. tuberculosis) strain H37Rv. Among these compounds, compound 6i was the most effective antitubercular agent with an MIC of 1.0μg/mL. Most importantly, compound 6i also exhibited a potent effect against clinically isolated rifampicin- and isoniazid-resistant M. tuberculosis strains, suggesting a different mode of action from the current drugs. Therefore, it shows potential for the development of new anti-TB agents. [Copyright &y& Elsevier]

Abstract: Heart sound is one of the most important signals. However, the process of getting heart sound signal can be interfered with many factors outside. Heart sound is weak electric signal and even weak external noise may lead to the misjudgment of pathological and physiological information in this signal, thus causing the misjudgment of disease diagnosis. As a result, it is a key to remove the noise which is mixed with heart sound. In this paper, a more systematic research and analysis which is involved in heart sound denoising based on matlab has been made. The study of heart sound denoising based on matlab firstly use the powerful image processing function of matlab to transform heart sound signals with noise into the wavelet domain through wavelet transform and decomposition these signals in muli-level. Then for the detail coefficient, soft thresholding is made using wavelet transform thresholding to eliminate noise, so that a signal denoising is significantly improved. The reconstructed signals are gained with stepwise coefficient reconstruction for the processed detail coefficient. Lastly, 50HZ power frequency and 35Hz mechanical and electrical interference signals are eliminated using a notch filter. [Copyright &y& Elsevier]

The effect of porous carbon preform and the infiltration process on the properties of reaction-formed SiC have been investigated in this paper. Five different porous carbon preforms with porosity in a range 35–67% and pore size from 0.03 to 2.58 μm have been infiltrated with liquid or vapor Si. The porous carbon preform and infiltration process affect the reaction rate and infiltration rate, which are key issues in designing the final reaction-formed silicon carbide microstructure. Under suitable experimental conditions, vapor infiltration can lead to deeper infiltration of Si than liquid infiltration. The best result has been obtained by vapor Si infiltration with a relatively smaller scale porous carbon preform having a density of 0.92 g cm-3. The reaction-formed silicon carbide with a flexural strength 630 MPa and density 3.12 g cm-3 and Si-content 8 vol.%, which is superior to commercially obtained reaction-bonded silicon carbides, have been fabricated by Si vapor infiltration. [Copyright &y& Elsevier]

This paper describes the production of shaped silicon carbide based ceramic materials by in situ reaction of silicon with fine, ultra-uniform porous carbon skeletons that were produced from liquid polymer solutions without any particulate additions. Three typical types of carbon preforms (spherical carbon particulates, crosslinked network carbon, and lamellate carbon particulates) were infiltrated with molten Si. The morphologies and mechanical properties of corresponding reaction-formed silicon carbide (RFSC) ceramics have been investigated. The results revealed that the RFSC obtained by molten Si reaction with the porous carbon preform with discrete and spherical carbon particulates has the most uniform microstructure, the highest flexural strength (410±30 MPa) and the lowest amount of residual Si (approximately 12 wt.%). The general feature of a fracture surface showed the typically brittle failure in those materials. [Copyright &y& Elsevier]