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The carbon matrix composites with three-dimensional porous structure and multiple phases were prepared by heat treatment of nano-Fe and polyacrylonitrile (PAN) precursor with different content of nano-Fe. The phase and morphology changes of the samples during heat treatment were investigated, and their electromagnetic properties and microwave absorption performance were compared in the frequency range of 2–18 GHz. The Fe4N@Fe3O4@Fe/carbon composite presents a three-dimensional porous structure with an average pore size of 5 μm. Fe4N and Fe3O4 can be generated in situ by the reaction of Fe with active N and O in PAN, which is helpful to improve the dielectric and magnetic losses of the composite. PAN can be cyclized, crosslinked and pyrolyzed to form graphite carbon and amorphous carbon, and various reactions in the heat treatment process, the heterogeneous interfaces between magnetic phases and carbon matrix were formed, which can enhance the interfacial polarization relaxation. With the increase in nano-Fe content, the magnetic loss increases, and with the increase in magnetic particle content and coating thickness, the absorption peak tends to move to lower frequency. When the mass ratio of Fe/PAN in the precursor is 120%, the lowest reflection loss of the composite is − 37 dB at 13 GHz, and the effective absorption bandwidth is 3.23 GHz (11.54–14.77 GHz) with 1.5 mm thickness. When the mass ratio is 180%, the lowest reflection loss is − 33 dB at 4.7 GHz. This study not only provides a simple method to prepare porous carbon and ferromagnetic composites, but also shows that Fe4N has great potential in the application of wave absorbers. [ABSTRACT FROM AUTHOR]

This project accepts the larger ecosystem impacts of EAB but proposes that strategically preserved pockets of ash forest throughout Massachusetts could be beneficial for sensitive species, future research, and public engagement. In Massachusetts, the spread of EAB may cause the regional elimination of Fraxinus americana (white ash), which anchors the forest ecosystem through multi-species interaction. This project was developed in response to the impacts of the Agrilus planipennis (Emerald Ash Borer, hereafter EAB), an invasive species threatening North American forests. [Extracted from the article]

Yellow Monascus pigments were prepared from fermentation broth after extractive fermentation in nonionic surfactant micelle aqueous solution. First, Monascus pigments were transferred from nonionic surfactant micelle aqueous solution into ionic liquid phase by ionic liquid based microemulsion extraction, in which the recovery yield of yellow Monascus pigments based on absorbance at 410 nm reached to 95.5%. Then, the yellow Monascus pigments in the ionic liquid phase were recovered by ionic liquid–butanol two-phase extraction, in which the recovery yield of yellow Monascus pigments reached to approximately 95%. Further purification of yellow Monascus pigments was demonstrated by removal of orange Monascus pigments via selective aminophilic reaction between orange Monascus pigments and MSG (monosodium glutamate). The results indicated that there was no aminophilic reaction between yellow Monascus pigments and primary amines by replacement of 4-H-pyran cycle in orange Monascus pigments with 2-H-pyran cycle in yellow Monascus pigments. This fundamental fact provides a novel strategy for removal of orange Monascus pigments from yellow ones. It also sheds light on why orange Monascus pigments but yellow ones exhibit strong cytotoxicity. [ABSTRACT FROM AUTHOR]

[Display omitted] Modulating the structure and morphology is essential in fabricating high-performance electromagnetic absorbing materials. Herein, we obtained porous Fe 3 O 4 /carbon hollow microspheres and porous Fe 4 N/carbon hollow microspheres derived from Fe-glycerol hollow microspheres. Through structure and morphology analysis, we proved the existence of porous and hollow features. By comparison, it can be found that the porous Fe 4 N/carbon hollow microspheres have electromagnetic wave absorption performance superior to that of porous Fe 3 O 4 /carbon hollow microspheres. The reflection loss value of porous Fe 4 N/carbon hollow microspheres reaches −42.2 dB at a matching thickness of merely 1.4 mm, and its effective absorbing bandwidth approaches 4.5 GHz, whereas the reflection loss of porous Fe 3 O 4 /carbon hollow microspheres in the 2–18 GHz range is over −10 dB. Reasons for the better electromagnetic wave absorption performance are revealed to be that the magnetic Fe 4 N has higher complex permittivity and complex permeability, and the porous hollow microspherical structure increases the multiple scattering and reflection of electromagnetic waves. Meanwhile, the impedance matching and attenuation constant are optimized together through the synergy of dielectric and magnetic loss. This research can provide instructive findings for thin-thickness electromagnetic wave absorbing materials based on Fe 4 N with an appropriate microstructure. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we will study the local well-posedness of Schrödinger-Improved Boussinesq System with additive noise in , , and we will also study the global well-posedness of dimension 1 case with the initial data almost surely, gaining some exponential growth of norm of v. [Copyright &y& Elsevier]

Steel wire reinforced thermoplastic pipe (PSP) is a polymer–matrix composite pipe of excellent quality, and it shows great potential in different industries. In this study, bearing capacity of PSP under combined internal pressure and bending moment at various temperatures was investigated. Tests were conducted through a specifically designed mechanical testing system, and the temperatures varied from 20 °C to 60 °C. With a pre-set internal pressure of 2.8 MPa, bending moment was applied until failure. It was found that the fracture of steel wires leads to the failure of pipe, and higher temperature has a negative effect on the pipes' bending capacity. A finite element (FE) model was subsequently established to analyze the failure process and influence factors of PSP under combined loads. • A testing system for composite pipes under complex loads was developed. • Failure modes of SRTP under combined loads at different temperatures were studied. • A experimentally verified FEA model was used to analyze key factors in SRTP failure. [ABSTRACT FROM AUTHOR]

In this paper, we prove an L2-concentration result of Zakharov system in space dimension two, with radial initial data $(u_0,n_0,n_1) \in H^s \times L^2 \times H^{-1} (\frac{16}{17} < s < 1)$, when blow up of the solution happens by I-method. In addition to that, we find a blow up character of this system. Furthermore, we improve the global existence result of Bourgain's to the above-mentioned spaces. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we shall estimate the growing speed for higher Sobolev norms of the solutions to Schrödinger equations on Riemannian manifolds (), under some bilinear Strichartz estimate assumptions. [Copyright &y& Elsevier]

Abstract: In this paper we prove a global existence result for nonlinear Klein–Gordon equations in infinite homogeneous waveguides, , with smooth small data, where is a Zoll manifold, or a compact revolution hypersurface. The method is based on normal forms, eigenfunction expansion and the special distribution of eigenvalues of the Laplace–Beltrami on such manifolds. [Copyright &y& Elsevier]

Abstract: In this paper, we consider solutions of the -critical focusing nonlinear Schrödinger equation on for the initial data in (), mainly about the concentration phenomena for blow-up solutions and global well-posedness for small initial data. [Copyright &y& Elsevier]

[Display omitted] • A simple ball milling process was used to prepare flaky FeSiAl. • Excellent low-frequency electromagnetic wave absorption performance. • Low-frequency electromagnetic wave absorption mechanism is closely related to magnetic loss. • The relationships of morphology and electromagnetic wave absorption properties were disclosed. The effect of morphology and size on electromagnetic wave (EMW) absorption performance has been a relentlessly explored issue. By grinding the spherical FeSiAl alloy powder in a planetary ball mill, a flaky FeSiAl alloy with higher saturation magnetization, dielectric constant, magnetic permeability, and better impedance matching at low frequency was prepared. The phase composition, morphology, and static magnetism of FeSiAl alloys with different morphologies were studied through X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). The electromagnetic parameters and absorption properties of the two kinds of powders were studied using a vector network analyzer (VNA). The results show that the crystallinity, dielectric constant, and magnetic permeability of the flaky FeSiAl powder increase compared with the spherical one. The absorption performance in the low-frequency band was remarkably improved after grinding. When the matching thickness is 6.5 mm, the reflection loss at 1 GHz reaches −16.89 dB for the flaky FeSiAl. The excellent EMW absorption performance of flaky FeSiAl alloy powder at low-frequency is mainly due to the large magnetic permeability and magnetic loss which is derived from the magnetocrystalline anisotropy brought about by lamellar morphology and appropriate impedance matching as well. This work provides a new idea for the preparation of low-frequency absorbing materials expected to be used in the L-band wave absorption field. [ABSTRACT FROM AUTHOR]

Most commercial polyacrylonitrile-based carbon fibers are microfibers derived from the wet-spinning or dry-jet wet-spinning polyacrylonitrile fiber. Nano carbon fibers made by electrospinning and post-processing have many advantages over micro carbon fibers in performance, but the research on nano carbon fibers is far from enough. In this work, polyacrylonitrile-based nano- and microfibers obtained by electrospinning and dry-jet wet spinning are converted into nano- and micro carbon fibers under the same pre-oxidation and carbonization conditions. The evolution of morphology, elemental content, functional groups and apparent crystallinity of the two size-scale fibers before and after carbonization are studied. The relationship between their structure and their electrical property is speculated. The results show that pre-oxidized nano fibers' absorption of visible light is much weaker than microfibers. The oxygen content of the pre-oxidized nanofibers is higher, and the carbon content in the carbonization process is always higher than that of microfibers. The nanofibers are more accessible to crystallize than microfibers. They can obtain better electrical properties than microfibers and have a more excellent application prospect as conductive fillers in antistatic composites. [ABSTRACT FROM AUTHOR]

Leak test is required in a number of standards to verify the leak tightness of pipelines based on the pressure drop in the pressure-hold period. However, the viscoelasticity of the matrix material polythene in plastic pipe reinforced by cross helically wound steel wires (PSP) would cause an evident pressure drop in leak test. In this study, a theoretical model was proposed to investigate the effect of viscoelasticity on the hold pressure through combining a long-term mechanical model of PSP and water state equation. Leak tests were conducted to validate the model, and a good agreement was obtained. Results showed that the pressure rapidly declined initially, and then the decreasing rate slowed until the pressure was almost stable. Finally, the principal mechanical performance of PSP was further explored, and the effects of pressurization rate and temperature on the pressure drop were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we prove a global existence result for nonlinear Klein–Gordon equations with small data in infinite homogeneous waveguids, , where is a Zoll manifold. The method is based on the normal forms, the eigenfunction expansion for M and the special distribution of eigenvalues of Laplace–Beltrami on Zoll manifold. [Copyright &y& Elsevier]

• A stealth coating with not only low infrared emissivity in mid and far infrared band, but also wave-transparent performance in the radar band. • The floating Al powder was firstly modified with paraffin wax (PW) and the effects of Al@PW powder on the various properties of the composite coatings were disclosed. • The composite coating can meet the multi-function requirements of airborne radome. Low Infrared (IR) emissivity coatings in military aerospace need to meet both stealth and radar transmission. At present, there are few research on this aspect, therefore how to solve the compatibility problem of low infrared emissivity and high radar wave transmission rate of materials is an important direction for the development of infrared stealth materials. A multi-functional composite coating with low IR emissivity, dielectric loss, and antistatic properties was prepared using modified floating aluminum powder (Al@PW), short-cut carbon fiber, and ethylene propylene diene monomer (EPDM) as the binder. The coating's properties were investigated, highlighting the effect of PW. The results indicate that modifying floating Al powder with PW is an effective solution to the trade-off between low IR emissivity and high wave transparency. At a dosage of 11 g (about 12.5 wt% in Al@PW), the coating demonstrated the best overall performance, including the IR emissivity of 0.582, the surface resistivity of 9.5 MΩ/□, the dielectric constant of 5.15, the dielectric loss angle tangent of 0.052, the tensile strength of 11.75 MPa, and the elongation at break of 516.10%. The composite coating may be used as a multi-functional protective coating for airborne radomes. [ABSTRACT FROM AUTHOR]

Polyethylene pipe reinforced by winding steel wires (PSP) has been widely used in many industrial areas. Understanding the relationship between the burst pressure of PSP and the varying environmental temperature is necessary because the mechanical properties of high-density polyethylene (HDPE) significantly vary at different environmental temperatures. In this study, a method based on classical laminated-plate theory was developed to predict the short-term burst pressure of PSP under various temperatures. HDPE uniaxial tensile tests were conducted under various temperatures to obtain different elastic HDPE moduli at different temperatures. The varied mechanical properties of the matrix HDPE were considered to result in the variation of PSP properties. Theoretical results of PSP burst pressure was determined by substituting the varied HDPE properties into the analysis model. Short-term PSP burst tests were conducted under various temperatures to validate the proposed method. The theoretical results agreed well with test results, with relative error ranging from 6.72% to 8.82%. The cause of errors was analyzed. Furthermore, the load carrying capacity of PSP was analyzed and discussed in detail based on the PSP analysis model. [ABSTRACT FROM AUTHOR]

• Floating aluminum powder coated with SiO 2 was prepared using tetraethyl orthosilicate (TEOS) as raw material by sol-gel method. • The composite coating was prepared using modified Al powder and antistatic carbonaceous fiber (CF) as filler, EPDM as binder. • The composite coating that we prepared has low infrared emissivity compatible with high radar wave transmittance. Low infrared emissivity coatings have been widely used in many fields. At present, there are few researches on coatings that are compatible with low infrared emissivity and high radar wave transmittance. In this paper, floating aluminum (Al) powder coated with SiO 2 was prepared using tetraethyl orthosilicate (TEOS) as raw material by sol-gel method. The composite coating was prepared using modified Al powder and antistatic carbonaceous fiber (CF) as filler, EPDM as binder. The surface morphology, infrared absorption properties of the modified Al powder and the infrared emissivity, surface resistivity, electromagnetic properties and mechanical properties of the composite coating were analyzed. The results show that with the increase of TEOS addition amount, more SiO 2 was covered to the surface of floating Al powder. By adjusting the thickness of the surface modification layer of floating Al powder, the dielectric constant (ε) and dielectric loss tangent values (tanδ) of the composite coating were significantly reduced. When the addition amount of TEOS is 1 g for Al@SiO 2 , the ε and tanδ can be significantly reduced, and the infrared emissivity was less than 0.6, the tensile strength (σ b) and elongation rate at break (e) decreased slightly. This suggests that the composite coating has low infrared emissivity compatible with high radar wave transmittance was obtained, which is expected to be applied to the surface of aircraft radome. [ABSTRACT FROM AUTHOR]

To investigate the anti-tumor activities of WZ35 and its possible molecular mechanism, bioinformatics analysis and the hematoxylin-eosin (HE) staining were applied to evaluate the Yes-associated-protein (YAP) level in gastric cancer. Cell counting kit-8 (CCK-8) was used to examine cell viability. Apoptosis was determined by flow cytometry analysis. Seahorse bioenergetics analyzer was used to investigate the alteration of oxygen consumption and aerobic glycolysis rate. SiRNA transfection was applied to silence endogenous YAP. Western blot was performed to detect indicated proteins. We found that treatment of gastric cancer cells with WZ35 exerted stronger anti-tumor activities than curcumin. Mechanistically, our research showed that WZ35 inhibited glycolysis, and induced reactive oxygen species (ROS) generation, resulting in Jun N-terminal Kinase (JNK) activation through downregulation of YAP in gastric cancer cells. ROS mediated YAP downregulation and JNK activation was regulated by glycolysis. Abrogation of ROS production markedly attenuated WZ35 induced anti-tumor activities as well as YAP downregulation and JNK activation. Similarly, the JNK inhibitor significantly reversed WZ35 induced anti-tumor activities in gastric cancer cells. Our study reveals a novel anti-gastric cancer mechanism of WZ35 by inhibiting glycolysis through the ROS-YAP-JNK pathway. WZ35 might be a potential therapeutics for the treatment of gastric cancer. Image 1 • Curcumin analogue WZ35 inhibits gastric cancer cell growth. • ROS mediated YAP and JNK activation was regulated by glycolysis. • Glycolysis throught ROS-YAP-JNK pathway might be a potential therapeutic target of gastric cancer. [ABSTRACT FROM AUTHOR]