Flexible FeSi/SiC ultrathin hybrid fiber mats with designable microwave absorption performance.

Flexible FeSi/SiC ultrathin fiber mats have been fabricated by electrospinning and high temperature treatment (1400 °C) using polycarbosilane (PCS) and ferric acetylacetonate (Fe(acac)) as precursors. The crystallization degree, flexibility, electrical conductivity, dielectric loss and microwave absorption properties of the hybrid fibers have been dramatically enhanced by the introduction of Fe. FeSi nanoparticles with a diameter around 500 nm are embedded in SiC fibers.

Effects of the ultrasound-assisted pretreatments using borax and sodium hydroxide on the physicochemical properties of Chinese fir.

This work investigated the physicochemical properties of Chinese fir after ultrasound-assisted pretreatments with borax and sodium hydroxide additives in an aqueous solution. TGA, FTIR, and XRD were used to analyze the thermal degradation processes, changes in chemical structures, and crystallinity of the treated samples, respectively. Additionally, the release of volatiles from wood pyrolysis was measured on-line by the TG-FTIR apparatus.

Changes of Chemical Composition and Hemicelluloses Structure in Differently Aged Bamboo ( Neosinocalamus affinis) Culms.

To study the differences in chemical composition analysis and spatial distribution of young Neosinocalamus affinis bamboo, we used the methods of standard of National Renewable Energy Laboratory and confocal Raman microscopy, respectively. It was found that the acid-soluble lignin and acid-insoluble lignin content showed an inverse relationship with the increasing bamboo age. Raman analysis revealed that Raman signal intensity of lignin in both the secondary cell wall and the compound middle lamella regions showed a similar increase trend with growth of bamboo.

Enhanced Flexibility and Microwave Absorption Properties of HfC/SiC Nanofiber Mats.

Hafnium carbide (HfC) phase, with a high melting point, excellent strength, and high electrical conductivity, could be a suitable addition to enhance the microwave absorption properties of one-dimensional silicon carbide (SiC) nanomaterials without sacrificing its high-temperature thermal stability. In the present work, HfC/SiC hybrid nanofiber mats with different HfC loading contents are fabricated by electrospinning and high-temperature pyrolysis. HfC hybrids with sizes of 5-10 nm are embedded in the SiC nanofibers.

Strengthening mechanisms, deformation behavior, and anisotropic mechanical properties of Al-Li alloys: A review.

Al-Li alloys are attractive for military and aerospace applications because their properties are superior to those of conventional Al alloys. Their exceptional properties are attributed to the addition of Li into the Al matrix, and the technical reasons for adding Li to the Al matrix are presented. The developmental history and applications of Al-Li alloys over the last few years are reviewed.

Effects of Ultrasound Pretreatment on Eucalyptus Thermal Decomposition Characteristics As Determined by Thermogravimetric, Differential Scanning Calorimetry, and Fourier Transform Infrared Analysis.

Samples were pretreated by ultrasound at 300 W and 28 kHz in three different solutions. The thermal degradation characteristics of the samples were then characterized via thermogravimetric, differential scanning calorimetry, and Fourier transform infrared analysis in a nitrogen environment. The characteristic of gas product release, the formation mechanisms of the main products, and the mechanistic basis for the effects of ultrasound on wood components were studied.

Synthesis and Evaluation of C15 Triene Urushiol Derivatives as Potential Anticancer Agents and HDAC2 Inhibitor.

A series of C15 triene urushiol derivatives were synthesized and evaluated for their anti-HepG2 aggregation in vitro. The results indicated that all compounds had an effective anti-HepG2 vitality. Compound was a potent inhibitor of HepG2 with IC of 7.

The flaky porous FeO with tunable dimensions for enhanced microwave absorption performance in X and C bands.

Special electric and magnetic characteristics make FeO widely applied in the electromagnetic (EM) wave absorption region. However, for pure FeO, it is still a challenge to simultaneously obtain high absorption intensity and broadband absorption at a low thickness, owing to its low dielectric property. As we realized, flake configuration and the porous structure have obviously promote the EM wave absorption property.

Synergies of urushiol and its pechmann derivative compatible with paclitaxel anti-HepG2 activity.

The paper investigated the synergistic inhibitory effects of (triene urushiol), (monoene urushiol), (urushiol pechmann derivative) and paclitaxel on proliferation of human hepatocellular carcinoma cell line HepG2. The inhibitory rate of cell proliferation was detected by MTT assay after HepG2 cells were separately treated with compounds , and combined with paclitaxel at different concentrations for 72 h. The joint index analysis was used to examine whether those compatible drugs had synergistic effect.

A Voltage-Boosting Strategy Enabling a Low-Frequency, Flexible Electromagnetic Wave Absorption Device.

Nowadays, low-frequency electromagnetic interference (<2.0 GHz) remains a key core issue that plagues the effective attenuation performance of conventional absorption devices prepared via the component-morphology method (Strategy I). According to theoretical calculations, one fundamental solution is to develop a material that possesses a high ε' but lower ε″.

Excellent microwave response derived from the construction of dielectric-loss 1D nanostructure.

Increasing efforts have recently been devoted to the artificial design and function of nanostructures for their application prospects in catalysis, drug delivery, energy storage, and microwave absorption. With the advantages of natural abundance, low cost, and environment friendliness, a one-dimensional (1D) MnO nanowire (MW) is the representative dielectric-loss absorber for its special morphology and crystalline structure. However, its low reflection loss (RL) value due to its thin thickness limits its wide development and application in the microwave absorption field.

Hierarchically Porous Multilayered Carbon Barriers for High-Performance Li-S Batteries.

As one of the most promising energy storage devices, the practical application of lithium-sulfur batteries is limited by the low electrical conductivity of sulfur and the notable "shuttle effects" of sulfur-based electrodes. In this work, we describe a hierarchically porous N-doped zeolitic imidazolate framework-8 (ZIF-8)-derived carbon nanosphere (N-ZDC) with an outer shell and an inner honeycomb-like interconnected nanosheet network as sulfur host material for high-performance and long-term lithium-sulfur batteries. The N-ZDC serves as multilayered barrier against the dissolution of lithium polysulfides.

Tribo-induced photoluminescent behavior of graphene and YSZ:Er/graphene composite films.

In the present work, a novel method was developed to study the evolving surface state of graphene film as it is subject to friction, characterized by photoluminescence properties. We prepared the graphene film (GF) and YSZ:Er (Er-Y co-doped ZrO)/graphene composite films (ZGCF). The Raman spectra and photoluminescence properties of the GF and ZGCF were characterized before and after the sliding friction.

The Dynamic Mechanical Analysis of Highly Filled Rice Husk Biochar/High-Density Polyethylene Composites.

In this study, rice husk biochar/high-density polyethylene (HDPE) composites were prepared via melt mixing followed by extrusion. Effects of biochar content and testing temperature on the dynamic mechanical analysis (DMA) of the composites were studied. Morphological analysis of the rice husk biochar and composites were evaluated by scanning electron microscopy (SEM).

SiC Nanofiber Mat: A Broad-Band Microwave Absorber, and the Alignment Effect.

Fiber alignment is a key factor that determines the physical properties of nanofiber mats. In this work, SiC nanofiber mats with or without fiber alignment are fabricated via electrospinning and the microwave electromagnetic properties of their silicone resin composites (5 wt %) are investigated in 2-18 GHz. By comparing with the composite containing SiC whisker, it is found that the nanofiber mats show superior dielectric loss and a minimal reflection loss (RL) of around -49 dB at 8.

Reinforcing Germanium Electrode with Polymer Matrix Decoration for Long Cycle Life Rechargeable Lithium Ion Batteries.

Germanium is a promising anode material for lithium ion batteries because of its high theoretical specific capacity and low operation voltage. However, a significant challenge in using Ge-based anodes is the large volume variation during cycling that causes pulverization and capacity fade. Despite intense studies in the past decade, unsatisfactory cycling stability of the Ge-based electrodes still impedes their widespread applications.

Achieving the interfacial polarization on C/FeC heterojunction structures for highly efficient lightweight microwave absorption.

Design of dielectric/magnetic heterostructure and multiple interfaces is a challenge for the microwave absorption. Thus, in this study, a novel C/FeC nanocomposites have been fabricated by annealing the precursors obtained by the facile chemical blowing of polyvinyl pyrrolidone (PVP) and Fe(NO)·9HO. By changing the content of Fe(NO)·9HO, the honeycomb-like structure with scads of pores and electromagnetic parameters could be successfully tailored.

Strong electric wave response derived from the hybrid of lotus roots-like composites with tunable permittivity.

Lotus roots-like NiO/NiCoO hybrids derived from Metal-organic frameworks (MOFs) are fabricated for the first time by using flake NiCo-MOF precursors as reactant templates. It was found that a thin sample consisting of 60 wt % NiO/NiCoO hybrids in the wax matrix exhibited an effective microwave absorption bandwidth of 4.2 GHz at the thickness of 1.

A co-production of sugars, lignosulfonates, cellulose, and cellulose nanocrystals from ball-milled woods.

This study demonstrated the technical potential for the large-scale co-production of sugars, lignosulfonates, cellulose, and cellulose nanocrystals. Ball-milled woods with two particle sizes were prepared by ball milling for 80min or 120min (BMW, BMW) and then enzymatically hydrolyzed. 78.

Influence of ultrasound-assisted extraction on the pyrolysis characteristics and kinetic parameters of eucalyptus.

In this study, the influence of ultrasound-assisted extraction on eucalyptus samples with special focus on pyrolysis characteristics and kinetic parameters was explored. Ultrasound and Soxhlet extraction were used to pretreat samples respectively, then samples were assayed by component analysis, TG-FTIR, and kinetic analysis. Ultrasound-assisted extraction did change the physiochemical characteristics of eucalyptus samples, particularly in regards to the quantity of extractives obtained.

Preparation and Characterization of Cellulose Nanocrystals from the Bio-ethanol Residuals.

This study was to explore the conversion of low-cost bio-residuals into high value-added cellulose nanocrystals. Two enzymatic hydrolyzed residuals (i.e.

Development of Eco-friendly Soy Protein Isolate Films with High Mechanical Properties through HNTs, PVA, and PTGE Synergism Effect.

This study was to develop novel soy protein isolate-based films for packaging using halloysite nanotubes (HNTs), poly-vinyl alcohol (PVA), and 1,2,3-propanetriol-diglycidyl-ether (PTGE). The structural, crystallinity, opacity, micromorphology, and thermal stability of the resultant SPI/HNTs/PVA/PTGE film were analyzed by the Attenuated total reflectance-Fourier transformed infrared (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), UV-Vis spectrophotometry, scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). The SPI/HNTs/PVA/PTGE film illustrated that HNTs were uniformly dispersed in the SPI matrix and the thermal stability of the film was enhanced.

A facile self-template strategy for synthesizing 1D porous Ni@C nanorods towards efficient microwave absorption.

Ni@C composites, which simultaneously possess porous, core-shell and 1D nanostructures have been synthesized with a facile self-template strategy. The precursors were obtained by a hydrothermal process using NiCl · 6HO and nitrilotriacetic acid as the starting material and then annealed at 400 °C, 500 °C, and 600 °C. The Ni@C composites annealed at 500 °C display a nanorod feature with a length of ∼3 μm and diameter of 230-500 nm.

Electrospinning of Fe/SiC Hybrid Fibers for Highly Efficient Microwave Absorption.

Fe/SiC hybrid fibers have been fabricated by electrospinning and subsequent high-temperature (1300 °C) pyrolysis in Ar atmosphere using polycarbosilane (PCS) and FeO precursors. It is found that the introduction of Fe has had a dramatic impact on the morphology, crystallization temperature, and microwave electromagnetic properties of the hybrid fibers. In addition, the Fe particles have acted as catalyst sites to facilitate the growth of SiCO nanowires on the surface of the hybrid fibers.

An efficient synthesis method targeted to a novel aziridine derivative of p-menthane from turpentine and its herbicidal activity.

A novel aziridine compound N-acetyl-1,2-azacyclo-p-menthane d was synthesised using turpentine as raw material and characterised by FT-IR, H NMR, C NMR, ESI-MS and HRMS. The pre-emergence herbicidal activities of d and its synthetic intermediates cis- and trans-N,N'-diacetyl-p-menthane-1,8-diamine (b2 and b1) were determined. The result showed that d exhibited much higher herbicidal activities against annual ryegrass, Digitaria sanguinalis and Ixeris denticulate than b2 and b1.