Analysis of financing mode selection for Gang-Zhu-Au Bridge

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Eliminación de DBP en aceite de onagra mediante arcilla activada modificada por chitosán y CTAB

The pollution of phthalic acid esters (PAEs) in edible oils is a serious problem. In the current study, we attempt to remove dibutyl phthalate ester (DBP) from evening primrose oil (EPO) with modified activated clay. The activated clay, commonly used for de-coloration in the oil refining process, was modified by chitosan and hexadecyl trimethyl ammonium bromide (CTAB). The modifications were characterized by SEM, XRD, and FT-IR. We further tested the DBP adsorption capacity of CTAB/chitosan-clay and found that the removal rate was 27.56% which was 3.24 times higher than with pristine activated clay. In addition, the CTAB/chitosan-clay composite treatment had no significant effect on the quality of evening primrose oil. In summary, the CTAB/chitosan-clay composite has a stronger DBP adsorption capacity and can be used as a new adsorbent for removing DBP during the de-coloration process of evening primrose oil.La contaminación por ésteres de ácido ftálico (PAEs) en los aceites comestibles es un problema grave. En el presente estudio, intentamos eliminar el éster de ftalato de dibutilo (DBP) del aceite de onagra (EPO) con arcilla activada modificada. La arcilla activada, comúnmente utilizada en la decoloración en el proceso de refinación de los aceites, fue modificada con chitosán y bromuro de hexadecil trimetil amonio (CTAB). Las modificaciones se caracterizaron mediante SEM, XRD y FT-IR. Además, probamos la capacidad de adsorción de DBP de CTAB / chitosán-arcilla y descubrimos que la tasa de eliminación era del 27,56%, que era 3,24 veces mayor que la arcilla activada pura. Además, el tratamiento compuesto de CTAB/chitosán-arcilla no tuvo un efecto significativo sobre la calidad del aceite de onagra. En resumen, el compuesto CTAB/chitosán-arcilla tiene una capacidad de adsorción de DBP más fuerte y se puede utilizar como un nuevo adsorbente para eliminar DBP durante el proceso de decoloración del aceite de onagra

Heat dissipation in atomic-scale junctions

Atomic and single-molecule junctions represent the ultimate limit to the miniaturization of electrical circuits. They are also ideal platforms to test quantum transport theories that are required to describe charge and energy transfer in novel functional nanodevices. Recent work has successfully probed electric and thermoelectric phenomena in atomic-scale junctions. However, heat dissipation and transport in atomic-scale devices remain poorly characterized due to experimental challenges. Here, using custom-fabricated scanning probes with integrated nanoscale thermocouples, we show that heat dissipation in the electrodes of molecular junctions, whose transmission characteristics are strongly dependent on energy, is asymmetric, i.e. unequal and dependent on both the bias polarity and the identity of majority charge carriers (electrons vs. holes). In contrast, atomic junctions whose transmission characteristics show weak energy dependence do not exhibit appreciable asymmetry. Our results unambiguously relate the electronic transmission characteristics of atomic-scale junctions to their heat dissipation properties establishing a framework for understanding heat dissipation in a range of mesoscopic systems where transport is elastic. We anticipate that the techniques established here will enable the study of Peltier effects at the atomic scale, a field that has been barely explored experimentally despite interesting theoretical predictions. Furthermore, the experimental advances described here are also expected to enable the study of heat transport in atomic and molecular junctions, which is an important and challenging scientific and technological goal that has remained elusive.Comment: supporting information available in the journal web site or upon reques

Effect of laser remelting on microstructure and properties of WC reinforced Fe-based amorphous composite coatings by laser cladding

The WC reinforced Fe-based amorphous composite coatings were prepared by laser cladding with rectangular spot. The effect of laser remelting on the microstructure and properties of composite coatings was investigated. The results showed that laser remelting can reduce the cracks and porosities of the cladding coating and improve its surface quality. Large amounts of crystalline phases were precipitated at the top of the cladding and remelting coatings. However, the microstructure at the top of the remelting coating was finer compared to that at the top of the cladding coating. With increasing distance from the surface of substrate, the amorphous phase appeared within the remelting coating and large amounts of carbides rich in Fe and Mo, Fe23B6, gamma-Fe and Cr-9.1.Si-0.9 Slag phases were also precipitated in the remelting coating. As a result, the corrosion resistance of the remelting coating was higher than that of the cladding coating. The microhardness of the remelting coating was approximately 1.13 times higher than that of the cladding coating. (C) 2018 Elsevier Ltd. All rights reserved

Experimental observation of topological Fermi arcs in type-II Weyl semimetal MoTe2

Weyl semimetal is a new quantum state of matter [1-12] hosting the condensed matter physics counterpart of relativisticWeyl fermion [13] originally introduced in high energy physics. The Weyl semimetal realized in the TaAs class features multiple Fermi arcs arising from topological surface states [10, 11, 14-16] and exhibits novel quantum phenomena, e.g., chiral anomaly induced negative mag-netoresistance [17-19] and possibly emergent supersymmetry [20]. Recently it was proposed theoretically that a new type (type-II) of Weyl fermion [21], which does not have counterpart in high energy physics due to the breaking of Lorentz invariance, can emerge as topologically-protected touching between electron and hole pockets. Here, we report direct spectroscopic evidence of topological Fermi arcs in the predicted type-II Weyl semimetal MoTe2 [22-24]. The topological surface states are confirmed by directly observing the surface states using bulk-and surface-sensitive angle-resolved photoemission spectroscopy (ARPES), and the quasi-particle interference (QPI) pattern between the two putative Fermi arcs in scanning tunneling microscopy (STM). Our work establishes MoTe2 as the first experimental realization of type-II Weyl semimetal, and opens up new opportunities for probing novel phenomena such as exotic magneto-transport [21] in type-II Weyl semimetals.Comment: submitted on 01/29/2016. Nature Physics, in press. Spectroscopic evidence of the Fermi arcs from two complementary surface sensitive probes - ARPES and STS. A comparison of the calculated band structure for T_d and 1T' phase to identify the topological Fermi arcs in the T_d phase is also included in the supplementary informatio

A review of physical supply and EROI of fossil fuels in China

This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil production will likely reach its peak, at about 230 Mt/year (or 9.6 EJ/year), in 2018; its total gas production will peak at around 350 Bcm/year (or 13.6 EJ/year) in 2040, while coal production will peak at about 4400 Mt/year (or 91.9 EJ/year) around 2020 or so. In terms of the forecast production of these fuels, there are significant differences among current studies. These differences can be mainly explained by different ultimately recoverable resources assumptions, the nature of the models used, and differences in the historical production data. Due to the future constraints on fossil fuels production, a large gap is projected to grow between domestic supply and demand, which will need to be met by increasing imports. Net energy analyses show that both coal and oil and gas production show a steady declining trend of EROI (energy return on investment) due to the depletion of shallow-buried coal resources and conventional oil and gas resources, which is generally consistent with the approaching peaks of physical production of fossil fuels. The peaks of fossil fuels production, coupled with the decline in EROI ratios, are likely to challenge the sustainable development of Chinese society unless new abundant energy resources with high EROI values can be found

Strain induced exciton fine-structure splitting and shift in bent ZnO microwires

Lattice strain is a useful and economic way to tune the device performance and is commonly present in nanostructures. Here, we investigated for the first time the exciton spectra evolution in bent ZnO microwires along the radial direction via high spatial/energy resolution cathodeluminescence spectroscopy at 5.5 K. Our experiments show that the exciton peak splits into multi fine peaks towards the compressive part while retains one peak in the tensile part and the emission peak displays a continuous blue-shift from tensile to compressive edges. In combination with first-principles calculations, we show that the observed NBE emission splitting is due to the valence band splitting and the absence of peak splitting in the tensile part maybe due to the highly localized holes in the A band and the carrier density distribution across the microwire. Our studies may pave the way to design nanophotonic and electronic devices using bent ZnO nanowires

In-situ FT-IR study of high pressure syngas conversion over Rh/SiO2 and Rh/NaY catalysts

High pressure syngas [V(CO) : V(H-2) = 1] conversion over unpromoted Rh catalyst supported on silica and zeolite NaY were studied at 250 degreesC with an in-situ. IR cell that avoided contamination of iron carbonyls. Change of the syngas pressure produced no effect on the IR spectrum of Rh/SiO2; bridged and linear CO on Rh clusters were the only detectable surface species under 0.1 to 1.0 MPa of flowing syngas. In addition to the bridged and linear CO species, two types of dicarbonyls [Rh(I)(CO)(2)] and a small amount of Rh-6(CO)(16) were formed when Rh/NaY was exposed to 0.1 MPa syngas. Increasing of the syngas pressure to 1. 0 MPa over Rh/NaY resulted in transformation of the dicarbonyls to Rh-6(CO)(16) and probably a mononuclear medium carbonyl featuring an absorption 2042 cm(-1). The detectable reaction products adsorbed on Rh/NaY catalyst under 1.0 MPa were monodentate and bidentate acetates. These surface species were maintained even after releasing the syngas pressure back to 0.1 MPa. Thus, a remarkable difference exists in the effect of syngas pressure on the strtucture of Rh catalysts: reconstruction of Rh catalyst under high pressure of syngas occurs in zeolite NaY but not on silica. Reactivity of the adsorbed surface species toward hydrogen after the catalyst reconstruction suggests that the monodentate acetate groups are responsible for the selective formation of acetic acid from syngas over the Rh/NaY catalyst