Magnetometers based on superconducting quantum interference devices (SQUIDs), fabricated from thin films of YBa2cu3O7-x and operated in liquid nitrogen at 77K, have achieved a magnetic field noise below 10 fT Hz(-1/2)...
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Magnetometers based on superconducting quantum interference devices (SQUIDs), fabricated from thin films of YBa2cu3O7-x and operated in liquid nitrogen at 77K, have achieved a magnetic field noise below 10 fT Hz(-1/2). These devices are now sufficiently sensitive for use in an intriguing variety of applications, including geophysics, magnetocardiology, nondestructive evaluation of metal structures, and scanning SQUID microscopes.
The synthesis of cuO/c nanocomposites was fabricated using an uncomplicated and eco-friendly method by cyperus rotundus (c. rotundus) leaf extract. The formation of nanocomposites and their size were optimized with va...
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The synthesis of cuO/c nanocomposites was fabricated using an uncomplicated and eco-friendly method by cyperus rotundus (c. rotundus) leaf extract. The formation of nanocomposites and their size were optimized with various factors, such as operational parameters, viz. exposure time, temperature, and concentration of the precursor, by response surface methodology (RSM). The effects of the synthesis of cuO/c nanocomposite samples and their characterization by various analytical techniques such as UV, XRD, XPS, EDX, SEM, and TEM have been reviewed and confirmed. The XRD patterns revealed that the biosynthesized cuO/c sample exhibited a monoclinic and crystalline structure. Moreover, the elements available in nanocomposites were determined as cu 2p, O 1 s, and c1s using XPS analysis. The TEM pictures reveal the morphology of the nanocomposites as spherical in form, with an average size of 30 nm. Additionally, synthesized cuO/c nanocomposites were examined for toxic effects on the mortality of two-winged insect larvae, and they were absolutely found to be extremely active and considerably kill larvae. The molecular docking study found that the nanocomposites were able to bind to the target protein with high affinity, which suggests that they are likely to be effective larvicidal agents. Our existing analysis findings can open up a replacement void for the larvicidal analysis exploiting biosynthesized nanocomposites.
Thermal silazane cleavage of dichloroboryldisilylamines (SiclmMe3-m)N(SiMe3)(Bcl2) (1: m?=?1;2: m?=?2) at 196 degrees c leads to the borazine derivates [(SiclmMe3-m)NB(clnMe1-n)]3 (3: m?=?1, n?=?0.185;4: m?=?2, n?=?0....
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Thermal silazane cleavage of dichloroboryldisilylamines (SiclmMe3-m)N(SiMe3)(Bcl2) (1: m?=?1;2: m?=?2) at 196 degrees c leads to the borazine derivates [(SiclmMe3-m)NB(clnMe1-n)]3 (3: m?=?1, n?=?0.185;4: m?=?2, n?=?0.111) characterized by NMR and IR spectroscopy and mass spectrometry. Single-crystal X-ray diffraction structure analyses reveal (BN)3 units with unusual twisted boat conformations in both compounds. Additionally, more detailed studies are done to clear up the function of the by-products (SiclmMe3-m)N(SiclMe2)(BclMe) formed during the cyclization step leading to asymmetrically boron substituted borazine derivatives. The single-source precursors 3 and 4 were cross-linked with methylamine producing polymers 3P and 4P, which were transformed into black amorphous materials with ceramic yields of 20.8 % and 50.3 %, respectively. ceramic 4c (Si1.00B0.98?N2.55?c1.37O0.05) was further investigated by 11B and 29Si magic angle spinning (MAS) NMR spectroscopy. A combined study of high-temperature TG analyses and X-ray powder diffraction analyses confirms the thermal stability of 4c up to 1670 degrees c. copyright (c) 2012 John Wiley & Sons, Ltd.
A novel method to prepare a coating on the c/ccomposite is discussed. The precursor infiltration pyrolysis method is usually applied to prepare interior ceramic matrix, thus Sic nanowires that can absorb the surficia...
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A novel method to prepare a coating on the c/ccomposite is discussed. The precursor infiltration pyrolysis method is usually applied to prepare interior ceramic matrix, thus Sic nanowires that can absorb the surficial precursor are added to prepare surficial ceramics. The method accomplishes the integration of the coating and the matrix so that no coating peels off after ablation. Moreover, the material with a Zrc/Sic precursor ratio of 5:1 (Z5S1), whose mass and linear rates are 0.47 mg/s and 0.95 mu m/s, exhibits the highest overall resistance to ablation. The results demonstrate that higher Zrccontent and more uniform phase distribution are beneficial to keep ZrO2 in solid and form a denser and firmer oxide layer, which is more effective in improving the ablation resistance of the c/ccomposite.
Aimed to enhance the high-temperature service performance of c/Siccomposites in high-speed aircraft thermal protection system, in this article, pitch-based carbon fibers were used to construct high thermal conductive...
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Aimed to enhance the high-temperature service performance of c/Siccomposites in high-speed aircraft thermal protection system, in this article, pitch-based carbon fibers were used to construct high thermal conductive channels to improve the heat transfer capability of c/Siccomposites. The results revealed that the as-prepared composites equipped with 4.7 times higher thermal conductivity than that of conventional c/Siccomposites. The oxyacetylene flame ablation test confirmed that the constructed high thermal conductive channels, which quickly conducted the heat flow from the ablation center area to other areas is the main reason of as-prepared composites exhibiting a very impressive ablation resistance property. Briefly, the ablation temperature of the as-prepared composite surfaces considerably dropped by about 300 & DEG;ccompared with conventional c/Siccomposites, while the linear ablation rate and mass ablation rate of the composites are 1.27 & mu;m/s and 0.61 mg/s respectively, which is superior to many recent reports, demonstrating that this article provides a simple but highly effective measure to improve the ablation resistance property of c/Siccomposites.
In order to enhance ablation resistance of c/ccomposites, Zr1-xHfxc and Sic were intro-duced into c/ccomposites, and ablation behavior of the composites was studied. In the composites (cHZS), Hfc and Zrc produced a ...
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In order to enhance ablation resistance of c/ccomposites, Zr1-xHfxc and Sic were intro-duced into c/ccomposites, and ablation behavior of the composites was studied. In the composites (cHZS), Hfc and Zrc produced a solid solution, and solid solubility of Hfc in Zrc was 0.4, which indicated that the solid solution was defined to be Zr0.6Hf0.4c. compared with c/c-Zrc-Siccomposites (cZS), cHZS possessed a better ablation resistance. During ablation of cHZS, Zr0.6Hf0.4c is oxidized to produce HfO2 and ZrO2, and HfO2 particles played a pinning effect, which fixed molten oxide coating. Moreover, due to low cTE of HfO2 and decreasing content of ZrO2, there was a smaller thermal stress and its distribu-tion area on cHZS ablation surface, thus thermal stress corrosion was weakened to strengthen integrity of oxide coating. In this case, a complete and continuous HfO2-ZrO2 coating was formed on cHZS surface, which could resist oxygen diffusion and reduce oxidation rate of the composites.& cOPY;2023 The Authors. Published by Elsevier B.V. This is an open access article under the cc BY-Nc-ND license (http://***/licenses/by-nc-nd/4.0/).
A five-band polarization-insensitive microwave metamaterial absorber (MMA) is discussed in this paper. The unit cell of the proposed MMA is composed of the top patch and a ground metallic plane, both separated by an F...
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A five-band polarization-insensitive microwave metamaterial absorber (MMA) is discussed in this paper. The unit cell of the proposed MMA is composed of the top patch and a ground metallic plane, both separated by an FR4 dielectric substrate having an ultrathin thickness of 0.014 lambda. The proposed absorber structure offers five different absorption peaks at 5.4 GHz (c band), 8.7 GHz (X band), 14.53 GHz, 15.25 GHz, and 15.68 GHz (Ku band) with the absorptivity of 98%, 86%, 99%, 99.8%, and 99.9%, respectively, for both transverse electric (TE) and transverse magnetic (TM) modes. The analysis of the electric field, magnetic field, polarization, and angle independency has been performed to understand the absorption mechanism easily. The sensing behavior of the structure is analyzed by adding the analyte over the top metal layer. The microwave MMA has been fabricated and measured. The fabrication results agree with the simulation results. The design of the proposed absorber is expected to find application in explosive detection, sensing, defense, and airborne radar applications.
Histone deacetylase (HDAc) inhibitors show clinical promise for the treatment of cancers, including hepatocellular carcinoma (Hcc). In this study, we investigated the effect of HDAc inhibitor treatment on hepatitis c ...
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Histone deacetylase (HDAc) inhibitors show clinical promise for the treatment of cancers, including hepatocellular carcinoma (Hcc). In this study, we investigated the effect of HDAc inhibitor treatment on hepatitis c virus (HcV)replication in Huh7 human liver cells and in a mouse model of HcV infection. Viral replication was markedly suppressed by the HDAc3 inhibitor at concentrations below 1 mmol/L, with no cellular toxicity. This was accompanied by upregulation of liver-expressed antimicrobial peptide 1 (LEAP-1) and downregulation of apolipoprotein-A1 (Apo-A1), as determined by microarray and quantitative RT-PcR analyses. Moreover, HDAc3 was found to modulate the binding of ccAAT-enhancer-binding protein a (c/EBPa), hypoxia-inducible factor 1 a (HIF1 a), and signal transducer and activator of transcription 3 (STAT3) to the LEAP-1 promoter. HDAc3 inhibitor treatment also blocked HcV replication in a mouse model of HcV infection. These results indicate that epigenetic therapy with HDAc3 inhibitor may be a potential treatment for diseases associated with HcV infection such as Hcc.
3D electrode design is normally opted for multiple advantages, however, instability/detachment of active material causes the pulverization and degradation of the structure, and ultimately poor cyclic stability. Here, ...
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3D electrode design is normally opted for multiple advantages, however, instability/detachment of active material causes the pulverization and degradation of the structure, and ultimately poor cyclic stability. Here, a dually protected, highly compressible, and freestanding anode is presented for sodium-ion batteries, where 3D carbon nanotube (cNT) sponge is decorated with homogeneously dispersed coSe2 nanoparticles (NPs) which are protected under carbon overcoat (cNT/coSe2/c). The 3D cNT sponge delivers enough space for high mass loading while providing high mechanical strength and faster conduction pathway among the NPs. The outer amorphous carbon overcoat controls the formation of solid electrolyte interphase film by avoiding direct contact of coSe2 with electrolyte, accommodates large volume changes, and ultimately enhances the overall conductivity of cell and assists in transmitting electron to an external circuit. Moreover, the hybrid can be densified up to 11-fold without affecting its microstructure that results in ultrahigh areal mass loading of 17.4 mg cm(-2) and an areal capacity of 7.03 mAh cm(-2) along with a high gravimetriccapacity of 531 mAh g(-1) at 100 mA g(-1). Thus, compact and smart devices can be realized by this new electrode design for heavy-duty commercial applications.
The transition-metal-catalyzed intramolecular hydroarylation of alkenes has been recognized as a straightforward approach for the construction of 3,3-disubstituted 2,3-dihydrobenzofurans. The reactions mainly rely on ...
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The transition-metal-catalyzed intramolecular hydroarylation of alkenes has been recognized as a straightforward approach for the construction of 3,3-disubstituted 2,3-dihydrobenzofurans. The reactions mainly rely on the reductive Heck reaction of aryl halides or the direct c-H bond activation of arenes bearing a directing group. This work realizes the Rh-catalyzed intramolecular hydroarylation of olefin-tethered benzocyclobutenols via c-c bond activation, which offers an alternative approach to 3,3-disubstituted 2,3-dihydrobenzofurans bearing a 4-beta-keto moiety. The methodology features 100% atom economy and pH-and redox-neutral conditions, and is applicable to the late-stage functionalization of complex molecules. The asymmetric variant has also been achieved with excellent enantioselectivities.
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