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In order to improve the mechanical properties of basalt fiber/epoxy composites, carboxylic CNTs were filled into the epoxy matrix of basalt fiber/epoxy composites. Firstly, the carboxylic CNTs filled epoxy composites with different carboxylic CNTs content were studied. Quasi-static and dynamic compression results show that when the content of carboxylic CNTs increased from 0wt% to 1wt%, both ultimate quasi-static and dynamic compressive strength of CNTs filled epoxy composites showed increasing tendencies. However when the content of carboxylic CNTs increased from 1 wt% to 1.5 wt% both ultimate quasi-static and dynamic compressive had decreasing tendencies. Base on above results, carboxylic CNTs (1wt%) filled basalt fiber/epoxy composites were fabricated by mould pressing method. Quasi-static and dynamic compression results showed that both ultimate quasi-static and ultimate dynamic compressive strength of carboxylic CNTs filled basalt fiber/epoxy composite were enhanced compared with those of basalt fiber/epoxy composites without CNTs. However, the critical failure strain were all lower than those of basalt fiber/epoxy composites without CNTs. Failure mechanism analysis showed that the carboxylic CNTs was beneficial for forming good interfacial bonding between epoxy matrix and basalt fibers, and the advantage of high axial tensile strength of basalt fibers could be fully utilized, which is responsible for the enhanced ultimate compressive strength of carboxylic CNTs filled basalt fiber/epoxy composites.

Aerogels with low density and excellent thermal insulation are seriously plagued by poor mechanical properties with low compressive moduli in the kPa range, especially in extreme conditions such as high temperatures and fires. In this work, a new double chemical cross-linking and physical cross-linking strategy is developed to synthesize ultrahigh-modulus aerogels with extreme-condition resistance from low-cost polyvinyl alcohol (PVA), bio-based phytic acid (PA) and montmorillonite (MMT). The resultant aerogels consist of interpenetrating networks with chemically cross-linked domains between PVA and PA and physically cross-linked domains among PVA, PA and MMT, leading to an ultrahigh compressive modulus of 41.9 MPa and a specific modulus of 455.4 MPa·cm3·g−1, which can even withstand a car crush. Benefitting from the formation of ultra-strong network backbones containing phosphorus and clay, the aerogels amazingly show excellent fire resistance and high-temperature thermal insulation features. This robust porous material can maintain its structural integrity and high modulus (~2 MPa) after exposure to extremely high-temperature flame (~1300 °C), and also exhibits high mechanical modulus of ~4 MPa after heating treatment at 900 °C. These special characteristics make the aerogel a promising insulation candidate in the fields of aviation, aerospace and other applications.

Electroless copper plating method combined with spark plasma sintering (SPS) was used to fabricate W-Cu alloy with low W-W contiguity. Results show that W-Cu alloy with low W-W contiguity and high relative density can be obtained by this method. With sintering temperature increased from 860°C to 1060°C, the relative density of W-Cu alloy shows a rapidly increasing tendency, but the W-W contiguity keeps at a low level. Compression testing results show that the ductility of prepared W-Cu alloy is sensitive to strain rate, and the failure strain of the W-Cu alloy shows obviously increasing tendency with the loading strain rate increased from 10-3 to 103.

Electroless copper plating on diamond particles precoated with 1% Cr was carried out to evaluate the effects of various experimental parameters on coating quality and deposition rate to obtain the optimized reaction parameters. The formulated samples under optimized parameters were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectra and optical microscopy. The best parameters, where uniform and maximum coating thickness was achieved, are etching with 20% NaOH for 30 min, sensitization and activation with SnCl 2 and PdCl 2 for 5 and 20 min, respectively. The composition of the copper solution bath was 16 g/L CuSO 4 ·5H 2 O, 35 mL/L formaldehyde (HCHO), 23 g/L KNaC 4 H 4 O 6 at 60 °C, pH=13 and stirring at (350±15) r/min under ultrasonication.

In order to improve the mechanical properties of the polyurethane foams, the silica nanoparticles were added into the foams in the form of SiO2/PEG suspension during the preparation process. The microstructure, density, static mechanical properties and dynamic mechanical properties of the foams were investigated. Microstructure analysis shows that the silica nanoparticles were uniformly dispersed in the foams, however when the amounts of SiO2/PEG suspension is more than 2.5 wt.%, cracks in the skelecton were observed in foams. With the increased SiO2/PEG suspension, the density, static compression strength and dynamic compression strength show an increasing tendency. When the SiO2/PEG suspension is 2.5 wt.%, the density of the foams increased 4.17 %, while the static compression strength increased 26 %. When the SiO2/PEG suspension is 10 wt.%, the density of the foams increased 16 %, while the dynamic compression strength increased 60.5 %. The corresponding mechanism was discussed in the paper.

Cu-coated carbon fiber cloth/Ti-6Al-4V composite (Cu-Cf/TC4) and uncoated-Cf/TC4 were fabricated by spark plasma sintering (SPS) method. The microstructure and dynamic compression properties of the Cf/TC4 composites were investigated. Results show that the matrix-fiber interfacial bonging in uncoated-Cf/TC4 is weaker than in Cu-Cf/TC4. Moreover, lamellar TiC exists throughout the TC4 matrix in uncoated-Cf/TC4, while there is no TiC generated in TC4 matrix of Cu-Cf/TC4. Dynamic compressive tests indicate the stress-strain curves of Cu-Cf/TC4 and uncoated-Cf/TC4 show no difference at a strain rate of 2500 s-1, while show significant difference at a strain rate of 4800 s-1. Further investigations find: (1) at a strain rate of 2500 s-1, the reinforcement effect of Cf on Cu-Cf/TC4 is similar to TiC on uncoated-Cf/TC4, explaining the exact similarity in compressive property of Cu-Cf/TC4 and uncoated-Cf/TC4; (2) at a strain rate of 4800 s-1 the reinforcement effect of Cf on Cu-Cf/TC4 is far more than TiC on uncoated-Cf/TC4, explaining the higher compressive strength of Cu-Cf/TC4; moreover, multiple debonding of carbon fiber and its squeezing into TC4 matrix constitute an important energy absorption mechanism for uncoated-Cf/TC4, explaining the better plasticity of uncoated-Cf/TC4.

Temperature being one of the most important parameters of Spark plasma sintering (SPS) and its effects on the microstructures as well as on the physical properties of copper diamond composites fabricated by mechanical mixing of copper with 70 vol.% diamond powders, precoated with 1 wt% chromium has been studied. Experiments were performed at 900°C, 1000°C and 1100 °C for 10 minutes under 50 MPa. The results reveal that sintering temperature highly influences the copper/diamond interface bonding and microstructures. The composite’s properties like thermal conductivity (T.C), specific heat (Cp), diffusivity (Dff) and relative density (ρr) were also highly influenced by temperature variations. Except the relative density, all the other properties increased respectively with increasing sintering temperature.

In order to evaluate the impact protection capacity of armor material quantitatively, direct impact testing loaded by modified Hopkinson bar was used to simulate the impaction between penetrator and armor. Protection coefficient k was defined to describe the protective performance. Using the direct impact testing, Ti-6Al-4V specimens with different microstructure and thickness were tested. Results show that k decreases with increased impact velocity and increases with increased thickness of specimen. Under a given loading condition, binary microstructure exhibits the highest k, indicating the best protective performance. Moreover, its k shows the most sensitivity to thickness (mt) and the least sensitivity to impact energy (me), which means that its protective performance can be improved most efficiently by increasing its thickness and it will exhibit good protective performance in a wider impact velocity range. This new method can evaluate the impact protective properties of armor materials efficiently, which may have a broad application prospect.

In the present study, we investigated the effectiveness of GLYX-13, an NMDA receptor glycine site functional partial agonist, to alleviate the enhanced anxiety and fear response in both a mouse and rat model of stress-induced behavioral changes that might be relevant to posttraumatic stress disorder (PTSD). Studies over the last decades have suggested that the hyperactivity of hypothalamic–pituitary–adrenal (HPA) axis is one of the most consistent findings in stress-related disease. Herein, we used these animal models to further investigate the effect of GLYX-13 on the stress hormone levels and glucocorticoid receptor (GR) expression. We found that exposure to foot shock induced long-lasting behavioral deficiencies in mice, including freezing and anxiety-like behaviors, that were significantly ameliorated by the long-term administration of GLYX-13 (5 or 10 mg/kg). Our enzyme-linked immunosorbent assay results showed that long-term administration of GLYX-13 at behaviorally effective doses (5 or 10 mg/kg) significantly decreased the elevated serum levels of both corticosterone and its upstream stress hormone adrenocorticotropic hormone in rats subjected to the TDS procedure. These results suggest that GLYX-13 exerts a therapeutic effect on PTSD-like stress responding that is accompanied by (or associated with) modulation of the HPA axis, including inhibition of stress hormone levels and upregulation of hippocampal GR expression.

Ni–W alloys coatings with minimum residual stress can be electrodeposited by using electrodepositing bath with additive saccharin at ∼2.5 g/L. Grain size of electroformed Ni–36.4 wt% W heat-treated at below 400 °C grew slowly with heat treatment temperature rising. However, it grew quickly as heat treatment temperature increased from 400 °C to 500 °C. The dynamic strength of electroformed Ni–36.4 wt% W alloy after heat treatment increases but the dynamic ductility decreases with strain rate increasing in the range of 2800–5400 s −1 . At the strain rate 2800 s −1 , the best dynamic strength and ductility of Ni–36.4 wt% W alloy can be obtained by heat treatment at 300 °C comparing with that as-deposited and heat treatment at 200–500 °C.

The dynamic behaviors of tungsten heavy alloy (WHA) processed by hot-hydrostatic extrusion (HE) and hot torsion (HT) were investigated. The HE + HT WHAs exhibit significant improved susceptibility to forming adiabatic shear bands (ASBs) and a remarkably high flow stress of 2400 MPa under uniaxial dynamic compression. With increasing plastic strain of HT, an obviously increasing tendency of localized shearing was observed. Elongated subgrains with an average width of 200–300 nm bonded together and formed parallel lamellar bands within the ASBs of WHA.

To study the cardiovascular effect of selective orexin-1 receptor (OX1R) antagonist SB408124 in anesthetized rats and explore the underlying mechanism by using intracerebroventricular (ICV) microinjection combined with immunohistochemical assay.The changes of mean arterial blood pressure (MAP) and heart rate (HR) of male Sprague-Dawley rats were recorded during ICV microinjection of SB408124 with or without pretreatment of atropine methyl nitrate or hexamethonium bromide. Furthermore, tyrosine hydroxylase (TH) immunopositive neurons in the rostral ventrolateral medulla (RVLM) of the rat were detected with immunohistochemical assay after ICV microinjection of SB408124.ICV administration of SB408124 resulted in a significant decrease in MAP in anesthetized rats, which was accompanied with a mild decrease in HR. The cardiovascular responses elicited by SB408124 were not abolished by pretreatment of atropine methyl nitrate whereas fully abolished by pretreatment of hexamethonium bromide. The number of TH-immunopositive neurons in rat RVLM were significantly decreased following ICV administration of SB408124.ICV microinjection of selective OX1R antagonist SB408124 can cause decreases of MAP and HR mediated by inhibiting sympathetic activity in anesthetized rats.

The administration of certain fluoroquinolone antibacterials has recently been linked to QT interval prolongation, raising the clinical concerns over the cardiotoxicity of these agents. In this study, the effects of a novel fluoroquinolone, antofloxacin hydrochloride (AX) on human-ether-à-go-go-related gene (HERG) encoding potassium channels and the biophysical mechanisms of drug action were performed with whole-cell patch-clamp technique in transiently transfected HEK293 cells. The administration of AX caused voltage- and time-dependent inhibition of HERG K+ current (I(HERG/MiRP1)) in a concentration-dependent manner but did not markedly modify the properties of channel kinetics, including activation, inactivation, deactivation and recovery from inactivation as well. In comparison with sparfloxacin (SPX), levofloxacin lactate (LVFX), the potency of AX to inhibit HERG tail currents was the least one, with an IC(50) value of 460.37 microM. By contrast, SPX was the most potent compound, displaying an IC(50) value of 2.69 microM whereas LVFX showed modest potency, with an IC(50) value of 43.86 microM, respectively. Taken together, our data suggest that AX only causes a minor reduction of I(HERG/MiRP1) at the estimated free plasma level.