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Atomically dispersed non-noble metal single-site catalysts (SSCs) provide a promising approach to meet the catalytic requirements that traditional nanoparticles cannot accomplish. However, they often suffer from formidable challenges of cumbersome route, unmanageable loading, inevitable burial of active site and insufficient stability. Herein, we present a facile and hard template-assisted spatial confinement strategy to prepare Co SSCs embedded in N-doped graphene-like carbon (NG) with ultra-high loading of 10.26 wt%, which is close to the parent CoPc (10.31 wt%). Furthermore, the microstructure, surface area and Co loading in the titled catalysts can be easily manipulated via altering the synthesis parameters. The optimized Co SSCs@NG-800-50 catalyst shows excellent transfer hydrogenation of nitrobenzene with > 99% conversion and 96.3% aniline selectivity as well as good universality for various nitroaromatics in the presence of HCOOH. DFT calculations in combination with elaborate experiments unveil that the active H is firstly generated by the dissociation of C-H bond rather than the recognized O-H bond in HCOOH, then it is used for the hydrogenation of nitroaromatics on CoN3 site in Co SSCs@NG-800-50 catalyst, revealing the reaction mechanism of the tandem catalysis. This report paves a novel route to design and construct efficient and high-loading non-noble metal SSCs.

A water model experiment and a transient 3D numerical model were designed and implemented to quantitatively evaluate the flow-induced erosion behavior of the refractory lining in a continuous casting tundish. A relationship between the erosion rate and flow characteristic parameters was proposed and experimentally verified. Boric acid tablets were used in the water model experiment to determine the flow-induced erosion rate, and the numerical model defined the two-phase flow pattern. The results indicate that the impacting and rubbing effects caused by the fluid flow can be quantitatively characterized by the turbulent kinetic energy and wall shear stress. The proposed empirical dependence describes the erosion rate of the boric acid tablet with acceptable accuracy. The most serious erosion occurs inside the turbulence inhibitor, and the erosion rate sharply drops and steadily reduces with the water flow outside the turbulence inhibitor. The influence of casting speed on the refractory erosion rate is also quantitatively analyzed using the developed model with the introduction of the proposed correction.

Herein, we report the preparation and characterisation of fluororubber coated superhydrophobic Poly (ethylene tetrapthalate) (PET) fabric and polyurethane (PU) sponge. The coating surface structure...

The demand for sustainable energy has motivated the development of artificial photosynthesis. Yet the catalyst and reaction interface designs for directly fixing permanent gases into liquid fuels are still challenged by sluggish mass transfer and catalytic kinetics at the gas-liquid-solid three-phase boundary. Here, we report that breathable metal-organic framework (MOF) membranes decorated with metal single-atoms (SAs) can synergistically promote the diffusion, adsorption, and activation of gas molecules (e.g. CO2, O2) to boost the photocatalytic conversion of them into liquid fuels. With Ir SAs as active centers, the defect-engineered MOF (e.g. NH2-UiO-66) matrixes can efficiently harvest visible light and sensitize the electronically tailored Ir SAs for reducing CO2 to HCOOH with the high activity of 0.51 mmol gcat-1 h-1 at the conventional three-phase reaction interface. Furthermore, the breathable SA/MOF membranes can directly convert humid CO2 gas into HCOOH at the high-throughput gas-solid interfaces, presenting a near-unity selectivity and an unprecedented activity of 3.38 mmol gcat-1 h-1. Similarly, with Pd SAs as active centers, the SA/MOF membrane can catalyze the O2-to-H2O2 conversion with an ultrahigh activity of 10.4 mmol gcat-1 h-1 under visible light, suggesting the wide applicability of our catalyst and reaction interface designs.

A new rare-earth polyborate, trisodium europium octaborate, Na3EuB8O15, was prepared using the high-temperature molten-salt method and structurally determined by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic space group P-1 and contains a one-dimensional [B8O15]∞ tube structure that is constructed from BO3 and BO4 polyhedra. The Eu3+ and Na+ cations reside in this structure to ensure cohesion and neutrality. The excitation spectra, emission spectra, decay time and Commission Internationale de l'Éclairage (CIE) chromaticity index of Na3EuB8O15 were studied. Under near-UV light excitation (393 nm), the polyborate shows an intense red emission, which mainly originates from the highest intensities of the 5D0→7F1 and 5D0→7F2 transitions.

Photocatalytic nitrogen fixation reaction can harvest the solar energy to convert the abundant but inert N2 into NH3. Here, utilizing metal-organic framework (MOF) membranes as the ideal assembly of nanoreactors to disperse and confine gold nanoparticles (AuNPs), we realize the direct plasmonic photocatalytic nitrogen fixation under ambient conditions. Upon visible irradiation, the hot electrons generated on the AuNPs can be directly injected into the N2 molecules adsorbed on Au surfaces. Such N2 molecules can be additionally activated by the strong but evanescently localized surface plasmon resonance field, resulting in a supralinear intensity dependence of the ammonia evolution rate with much higher apparent quantum efficiency and lower apparent activation energy under stronger irradiation. Moreover, the gas-permeable Au@MOF membranes, consisting of numerous interconnected nanoreactors, can ensure the dispersity and stability of AuNPs, further facilitate the mass transfer of N2 molecules and (hydrated) protons, and boost the plasmonic photocatalytic reactions at the designed gas-membrane-solution interface. As a result, an ammonia evolution rate of 18.9 mmol gAu-1 h-1 was achieved under visible light (>400 nm, 100 mW cm-2) with an apparent quantum efficiency of 1.54% at 520 nm.

The new route for recycling fly ash was proposed to prepare SiC reticulated porous ceramics (SRPCs) with high strength and increased efficient filtration for molten metal filtration. The effects of fly ash on the rheological characteristics, microstructure evaluation and wetting behavior between SRPCs and molten metal were investigated. It was found that the fly ash was beneficial to thixotropic property of SiC slurry when its content was less than 30 wt%. Furthermore, fly ash in SRPCs was completely transformed into mullite with needle-shape at 1300 °C, forming a porous structure containing micro pores and windows. SRPCs containing 20 wt% fly ash exhibited a higher strength because of the improved rheological properties of SiC slurry and the optimized microstructure in skeleton. In addition, the added fly ash in SRPCs could increase the contact angle between skeleton substrate and molten metal via microporosization of skeleton, thus exhibiting the potential ability to improve the filtration efficiency.

Identification of fossil corals is often limited due to poor preservation of external skeleton morphology, especially in the genus Acropora which is widespread across the Indo‐Pacific. Based on skeleton characteristics from thin section, we here develop a link between the internal skeleton structure and external morphology. Ten characteristics were summarized to distinguish Acropora and five related genera, including the type and differentiation of corallites, the skeleton nature of corallites (septa, columellae, dissepiments, wall), and calcification centers within septa. Acropora is distinctive for its dimorphic corallites: axial and radial. Isopora is similar to Acropora but possess more than a single axial corallites. Montipora and Astreopora (family Acroporidae) have monomorphic corallites and a synapticular ring wall, with clustered calcification center in the former and medial lines in the latter. Pocillopora and Porties are classified by distinctive dissepiments, columellae and septa. These microstructural skeleton characteristics were effective in the genus identification of fossil corals from drilled cores in the South China Sea. Eighteen detailed characteristics (ten of axial corallites, four of radial corallites, and four of coenosteum) were used in the Acropora species classification. The axial corallites size and structure (including corallite diameter, synapticular rings, and septa), the septa of radial corallites, and the arrangement of coenosteum were critical indicators for species identification. This identification guide can help paleoenvironmental and paleoecological analyses and modern coral reef conservation and restoration., Identification of fossil corals is often limited due to poor preservation of external skeleton morphology, especially in the genus Acropora which is widespread across the Indo‐Pacific. Based on skeleton characteristics from thin section, we here develop a link between the internal skeleton structure and external morphology.

On the basis of an undeveloped asymmetrical pyridylcarboxylate ligand, 2-(2-carboxypyridin-4-yl)terephthalic acid (H3CPTA), an indium pyridylcarboxylate framework, [(Me)2NH2]1.5[In1.5(CPTA)2]·5.5NMF·6H2O (1), is synthesized under solvent thermal conditions. 1 displays a 3D anionic framework with a large void space, which contains open square channels with a cross section of 14.6 A and a pore surface decorated with carboxylic oxygen atoms. Depending on the anionic skeleton and high water stability, 1 exhibits high adsorption selectivity and capacity for cationic dyes in aqueous solution. Furthermore, the luminescence performance illustrates that 1 has selectivity and sensitivity to nitenpyram with good recyclability.

The formation and removal of exogenous inclusions in a real-size two-strand tundish is simulated by the proposed unsteady 3D comprehensive numerical model of the respective fluid-structure interaction, which takes into account the impacting and washing effects on the refractory wear. A large eddy simulation is employed to describe the molten steel vortex flow. Thus, the thermal profiles of the molten steel and refractory lining are constructed. One-way coupled unsteady Euler-Lagrange approach is adopted to estimate the detachment and motion of the exogenous inclusion. The inclusion’s Reynolds number is utilized for evaluating the inclusion separation at the refractory lining after formation and at the upper surface of the molten steel. At a 1.2 m/min casting speed, 49 and 38 pct of exogenous inclusions are created at the turbulent inhibitor inner bottom and long nozzle inner wall, respectively. In contrast, only 13 pct of new inclusions are produced at all other inner walls. About 80 pct of newly generated inclusions are then trapped by free surfaces, 78 pct of which are removed at the first free surface. The initial diameter of exogenous inclusions ranges from 13 to 48 μm. The removal ratio of exogenous inclusions in the tundish first grows from 61 to 80 pct, with the casting speed rising from 1.0 to 1.2 m/min and then drops to 63 pct after the further casting speed rise to 1.4 m/min.

The present study investigated three lightweight periclase-magnesium aluminate spinel castables containing microporous magnesia aggregates with a varying apparent porosity (12.8%, 30.8% and 39.3%). The effect of the apparent porosity of the aggregates on the phase composition, microstructure, fracture behavior and strength of the lightweight castables was investigated by XRD, SEM and three-point bending tests. Large cracks between the aggregates with an apparent porosity of 12.8% and the matrix reduced the strength of the castable. For the aggregates with an apparent porosity of 30.8%, an excellent interlocking interface with the matrix increased the strength considerably, but also reduced the fracture toughness. At the highest level of the apparent porosity of the aggregates of 39.3%, the formation of a small number of microcracks between the aggregates and matrix reduced the strength, while the fracture toughness was only slightly affected. The lightweight castables with the best combination of properties were achieved at an apparent porosity of the aggregates of 30.8% since they had a low bulk density of 2.63 g/cm3 as well as a high compressive and flexural strength of 70.2 MPa and 20.9 MPa, respectively.

The new gravity field models of gravity field and steady-state ocean circulation explorer (GOCE), TIM_R6 and DIR_R6, were released by the European Space Agency (ESA) in June 2019. The sixth generation of gravity models have the highest possible signal and lowest error levels compared with other GOCE-only gravity models, and the accuracy is significantly improved. This is an opportunity to build high precision geostrophic currents. The mean dynamic topography and geostrophic currents have been calculated by the 5th (TIM_R5 and DIR_R5), 6th (TIM_R6 and DIR_R6) release of GOCE gravity field models and ITSG-Grace2018 of GRACE gravity field model in this study. By comparison with the drifter results, the optimal filtering lengths of them have been obtained (for DIR_R5, DIR_R6, TIM_R5 and TIM_R6 models are 1° and for ITSG-Grace2018 model is 1.1°). The filtered results show that the geostrophic currents obtained by the GOCE gravity field models can better reflect detailed characteristics of ocean currents. The total geostrophic speed based on the TIM_R6 model is similar to the result of the DIR_R6 model with standard deviation (STD) of 0.320 m/s and 0.321 m/s, respectively. The STD of the total velocities are 0.333 m/s and 0.325 m/s for DIR_R5 and TIM_R5. When compared with ITSG-Grace2018 results, the STD (0.344 m/s) of total geostrophic speeds is larger than GOCE results, and the accuracy of geostrophic currents obtained by ITSG-Grace2018 is lower. And the absolute errors are mainly distributed in the areas with faster speeds, such as the Antarctic circumpolar circulation, equatorial region, Kuroshio and Gulf Stream areas. After the remove-restore technique was applied to TIM_R6 MDT, the STD of total geostrophic speeds dropped to 0.162 m/s.

A bifunctional ligand strategy for modification of the functional pores is of great significance in the structural design of metal-organic frameworks (MOFs). Herein, a new 2-fold interpenetrated "pillared-layer" 3D Co-MOF, {[Co(HL)(4,4'-bipy)]·DMF·2H2O}n (1), was successfully synthesized by using two kinds of ligands, imidazolecarboxylic acid and pyridine. The metal-carboxylic layers are pillared by the 4,4'-bipy ligand, displaying a 3D framework with rectangular 3D channels (high BET surface of 190.9 m2 g-1 and maximum aperture of 3.9 A) that are decorated with abundant uncoordinated N and O atoms. 1 shows good water stability and thermal stability (320 °C). The proper pores and active sites endowed 1 with a selective adsorption of Congo red in aqueous solution. In addition, a high CO2 adsorption capacity and an excellent CO2 chemical conversion were observed.

Reported here is a concise total synthesis of (-)-berkelic acid in eight linear steps. This synthesis features a Catellani reaction/oxa-Michael cascade for the construction of the isochroman scaffold, a one-pot deprotection/spiroacetalization operation for the formation of the tetracyclic core structure, and a late-stage Ni-catalyzed reductive coupling for the introduction of the lateral chain. Notably, four stereocenters are established from a single existing chiral center with excellent stereocontrol during the deprotection/spiroacetalization process. Stereocontrol of the intriguing deprotection/spiroacetalization process is supported by DFT calculations.

Composites with high thermal conductivity and excellent electromagnetic interference (EMI) shielding performance are in urgent demand in the fields of wireless communication technologies and portable intelligent electronic devices. However, it remains a great challenge to simultaneously improve thermal conductivity and EMI shielding effectiveness (SE) for polymer composites. This work reports a feasible and scaled method relating to vacuum-assisted filtration and compression-molding to fabricate nylon/graphene nanoplatelet (GNP) composite papers using commercial nylon gauze and GNPs. The results show that the composite papers exhibit good flexibility and multifunctional performances. At 11.8 wt% GNPs, the three-layered composite nylon/GNP paper, which had a thickness of about 180 μm, showed high thermal and electrical conductivities of 15.8 W m−1 K−1 and 24.3 S cm−1, respectively, and an outstanding EMI SE of 58.1 dB at the X-band (8.2–12.4 GHz). The compromise of thermal conductivity and EMI SE of the composite paper is much greater than that of other multifunctional composites reported in the literature. Specifically, the composite papers also show greatly enhanced hydrophobicity and flame resistance and satisfactory mechanical properties. To sum up, this work paves the way for the real engineering application of nylon-based composite papers in next-generation electronic devices.

Duobaoshan is the largest porphyry-related Cu-Mo-Au orefield in northeastern (NE) Asia, and hosts a number of large-medium porphyry Cu (PCDs), epithermal Au and Fe-Cu skarn deposits. Formation ages of these deposits, from the oldest (Ordovician) to youngest (Jurassic), have spanned across over 300 Ma. No similar orefields of such size and geological complexity are found in NE Asia, which reflects its metallogenic uniqueness in forming and preserving porphyry-related deposits. In this study, we explore the actual number and timing of magmatic/mineralization phases, their respective magma genesis, fertility, and regional tectonic connection, together with the preservation of PCDs. We present new data on the magmatic/mineralization ages (LA–ICP–MS zircon U-Pb, pyrite and molybdenite Re–Os dating), whole-rock geochemistry, and zircon trace element compositions on four representative deposits in the Duobaoshan orefield, i.e., Duobaoshan PCD, Tongshan PCD, Sankuanggou Fe-Cu skarn, and Zhengguang epithermal Au deposits, and compiled published ones from these and other mineral occurrences in the orefield. In terms of geochronology, we have newly summarized seven magmatic phases in the orefield: (1) Middle-Late Cambrian (506–491 Ma), (2) Early and Middle Ordovician (485–471 Ma and ∼462 Ma), (3) Late Ordovician (450–447 Ma), (4) Early Carboniferous and Late-Carboniferous to Early Permian (351–345 and 323–291 Ma), (5) Middle-Late Triassic (244–223 Ma), (6) Early-Middle and Late Jurassic (178–168 Ma and ∼150 Ma), and (7) Early Cretaceous (∼112 Ma). Three of these seven major magmatic phases were coeval with ore formation, including (1) Early Ordovician (485–473 Ma) porphyry-type Cu-Mo-(Au), (2) Early–Middle Triassic (246–229 Ma) porphyry-related epithermal Au-(Cu-Mo), and (3) Early Jurassic (177–173 Ma) Fe-Cu skarn mineralization. Some deposits in the orefield, notably Tongshan and Zhengguang, were likely formed by more than one mineralization events. In terms of geochemistry, ore-causative granitoids in the orefield exhibit adakite-like or adakite-normal arc transitional signatures, but those forming the porphyry-/epithermal-type Cu-Mo-Au mineralization are largely confined to the former. The varying but high Sr/Y, Sm/Yb and La/Yb ratios suggest that the ore-forming magmas were mainly crustal sourced and formed at different depths (clinopyroxene-/amphibole-/garnet-stability fields). The adakite-like suites may have formed by partial melting of the thickened lower crust at 35–40 km (for the Early Ordovician arc) and >40 km (for the Middle-Late Triassic arc) depths. The Early Jurassic Fe-Cu skarn ore-causative granitoids show an adakitic-normal arc transitional geochemical affinity. These granitoids were likely formed by partial melting of the juvenile lower crust (35‒40 km depth), and subsequently modified by assimilation and fractional crystallization (AFC) processes. In light of the geological, geochronological and geochemical information, we proposed the following tectonometallogenic model for the Duobaoshan orefield. The Ordovician Duobaoshan may have been in a continental arc setting during the subduction of the Paleo-Asian Ocean, and formed the porphyry-related deposits at Duobaoshan, Tongshan and Zhengguang. Subduction may have ceased in the latest Ordovician, and the regional tectonics passed into long subsidence and extension till the latest Carboniferous. This extensional tectonic regime and the Silurian terrestrial-shallow marine sedimentation had likely buried and preserved the Ordovician Duobaoshan magmatic-hydrothermal system. The south-dipping Mongol-Okhotsk Ocean subduction from north of the orefield had generated the Middle-Late Triassic continental arc magmatism and the associated Tongshan PCD and Zhengguang epithermal Au mineralization (which superimposed on the Ordovician PCD system). The Middle Jurassic closure of Mongol-Okhotsk Ocean in the northwestern Amuria block (Erguna terrane), and the accompanying Siberia-Amuria collision, may have placed the Paleo-Pacific subduction system in NE China (including the orefield) under compression, and formed the granodiorite-tonalite and Fe-Cu skarn deposits at Sankuanggou and Xiaoduobaoshan. From the Middle Jurassic, the consecutive accretion of Paleo-Pacific arc terranes (e.g., Sikhote-Alin and Nadanhada) onto the NE Asian continental margin may have gradually distant the Duobaoshan orefield from the subduction front, and consequently arc-type magmatism and the related mineralization faded. The minor Late Jurassic and Cretaceous unmineralized magmatism in the orefield may have triggered mainly by the far-field extension led by the post-collisional (Siberia-Amuria) gravitational collapse and/or Paleo-Pacific backarc-basin opening.

We present a detailed DFT mechanistic study on the first Ni-catalyzed direct carbonyl-Heck coupling of aryl triflates and aldehydes to afford ketones. The precatalyst Ni(COD)2 is activated with the phosphine (phos) ligand, followed by coordination of the substrate PhOTf, to form [Ni(phos)(PhOTf)] for intramolecular PhOTf to Ni(0) oxidative addition. The ensuing phenyl-Ni(ii) triflate complex substitutes benzaldehyde for triflate by an interchange mechanism, leaving the triflate anion in the second coordination sphere held by Coulomb attraction. The Ni(ii) complex cation undergoes benzaldehyde C[double bond, length as m-dash]O insertion into the Ni-Ph bond, followed by β-hydride elimination, to produce Ni(ii)-bound benzophenone, which is released by interchange with triflate. The resulting neutral Ni(ii) hydride complex leads to regeneration of the active catalyst following base-mediated deprotonation/reduction. The benzaldehyde C[double bond, length as m-dash]O insertion is the rate-determining step. The triflate anion, while remaining in the second sphere, engages in electrostatic interactions with the first sphere, thereby stabilizing the intermediate/transition state and enabling the desired reactivity. This is the first time that such second-sphere interaction and its impact on cross-coupling reactivity has been elucidated. The new insights gained from this study can help better understand and improve Heck-type reactions.

Context Pomelo peel oil (PPO) [Citrus maxima (Burm.) Merr. (Rutaceae)] is reported to possess antioxidant and antimelanogenic activities. Objective To investigate the effect of PPO [Citrus maxima (Burm.) Merr. cv. Shatian Yu] on tumour necrosis factor-α (TNF-α)-induced necroptosis in cerebral ischaemia–reperfusion injury (CIRI) after cardiac arrest (CA). Materials and methods Male Sprague Dawley rats were randomly assigned to six groups: sham group, PP0-L (10 mg/kg), PPO-M (20 mg/kg), PPO-H (40 mg/kg) and two control groups (CA, 0.9% saline; Gly, 10% glycerol). All drugs were administered intravenously to the CA/CPR rats within 10 min after return of spontaneous circulation (ROSC). After 24 h, rats were assessed for neuronal injury via the neurological deficit score (NDS), cerebral cortex staining and transmission electron microscopy (TEM) and expression levels of TNF-α and necroptosis-related proteins by immunoreactivity staining and western blotting. Results Compared to those in the sham group (survival rate, 100% and NDS, 80), the survival rate and NDS were significantly reduced in the model groups (CA, 56.25%, 70; Gly, 62.5%, 71; PPO-L, 75%, 72; PPO-M, 87.5%, 75; PPO-H, 81.25%, 74). In the PPO-M group, Nissl bodies were significantly increased (43.67 ± 1.906 vs. 17 ± 1.732), the incidence of pathomorphological injury was lower and the necroptosis markers (TNF-α, RIPK1, RIPK3, p-MLKL/MLKL) expression was downregulated compared to those in the CA group (p

Controls on the formation and distribution of mineralization in continental collisional settings remain unclear. However, our synthesis of diverse geophysical data sets from the eastern margin of Tibet revealed that differential crustal rotation played a key role in the production of a variety of mineralization types. Due to Cenozoic continental collision between India and Eurasia, the elongated continental blocks in the eastern margin of Tibet were extruded and reoriented. Prior to block extrusion in the Eocene, two giant porphyry-skarn ore clusters formed at the boundaries between the central segment and both the northern and southern segments of the Jinshajiang-Ailaoshan suture zone. These crustal segment boundaries displayed counterclockwise rotation, due to clockwise rotation of the central segment relative to both the essentially immobile northern and southern segments, combined with crust-mantle decoupling. This is considered to have induced crustal friction and resultant generation of fertile magmas that formed the porphyry-skarn Cu-Au deposits. During Oligocene–Miocene block extrusion, differential rotation of upper crust occurred on the western and eastern sides of the north-northwest–trending Central Axis fault in the Lanping-Simao basin. Two Oligocene–Miocene Mississippi Valley–type ore clusters occur on fault segments with anomalous differential rotation of 70° to 80°, suggesting that this differential rotation resulted in local extension with consequent ore-fluid influx.

Toonayunnanaes A-E (1-5), five B-seco limonoids, along with five known compounds (6-10) were isolated from the bark of Toona ciliata. Compound 1 is a limonoid with a e-7(8)-lactone in the B ring, and compound 2 possesses a 1,14-oxygen bridge and a 15-OH. Their structures were elucidated by extensive spectroscopic analysis including 1D and 2D NMR, and HRESIMS. Compound 1 exhibited significant inhibition effect of NO production in LPS-stimulated RAW264.7 macrophages with an IC50 value of 10.94 ± 0.08 μM.

In this study, five mullite-corundum gas-permeable refractories reinforced by SiC whiskers were prepared with spherical porous mullite-corundum aggregates. The influence of the silicon powder content on the microstructure, phase composition, mechanical and gas-permeability properties were investigated through XRD, SEM and EDS. It was found that the silicon powder content strongly affected the mechanical and gas-permeability properties by changing the formation and distribution of mullite and SiC whiskers. SiC whiskers were formed both in the matrix and inside the pores of the aggregates. As the silicon powder content increased, the amount of SiC whiskers in the pores of the aggregates as well as at the aggregate/matrix interface increased, meanwhile more mullite was also formed at the interface. However, when the silicon powder content was larger than 9 wt%, much less mullite was observed at the interface, reducing the bonding between particles in the matrices. The formation of SiC whiskers and mullite at the interface improved the mechanical properties at a small expense of air permeability. The optimized refractory contained 6 wt% silicon powder which combined the highest cold and hot flexural strength (17.0 MPa and 10.2 MPa, respectively), as well as the best strain at fracture and a homogeneous gas permeability.

Eight previously undescribed lignan glycosides, viburmacrosides A-H (1-8), and seven known analogues (9-15) were isolated from Viburnum macrocephalum f. keteleeri fruits through bioactivity-guided fractionation. Their structures and absolute configurations were elucidated by extensive spectroscopic analyses and chemical evidence. Using the well-recognized carbohydrate-hydrolyzing enzymes α-amylase and α-glucosidase, as well as the promising protein tyrosine phosphatase 1B (PTP1B), as inhibitory targets, all isolated compounds were tested for their antidiabetic potential in vitro. Compound 4 displayed potent inhibitory activities with IC50 values of 9.9 ± 0.6 and 8.9 ± 0.5 μM against α-glucosidase and PTP1B, respectively. The enzymatic kinetics results suggested that compound 4 competitively inhibited α-glucosidase while it suppressed α-amylase and PTP1B in the mixed-type manner. These findings supported that V. macrocephalum f. keteleeri fruits may be a new functional food resource with antidiabetic potential.

Electromagnetic-thermal cosimulation of large antenna arrays is performed by using a supercomputing-based parallel domain decomposition method. In this letter, frequency-domain electromagnetic and thermal fields are solved self-consistently and then coupled via Joule heat and temperature-dependent material properties. The developed cosimulation solver is first validated with the commercial software COMSOL Multiphysics. Then, the parallel performance of our in-house developed code is examined in terms of scalability and efficiency. Finally, the temperature distributions over large-scale antenna arrays are obtained by our proposed solver in a highly efficient manner.

Twenty-four aryl benzyl sulfides, diaryl sulfides and dibenzyl sulfides were synthesized by four methods and characterized by 1H NMR, FT-IR and Gas chromatography. The reaction conditions of different synthesis methods were studied from the aspects of time, solvent, base and dispersant. The molecular structures of benzylphenyl sulfide (2S), (4-tert-butylbenzyl)(4-methylphenyl) sulfide (4S), (4-methylbenzyl)(4-methylphenyl) sulfide (9S), di(4-methylphenyl) sulfide (11S), (3,5-dimethylphenyl)(4-methyl phenyl) sulfide (15S), and dibenzyl sulfide (19S) [22] have been determined by single-crystal X-ray crystallography. Compounds 2S and 15S crystallize in the monoclinic space group P21/c, with a = 12.278(3), b = 15.894(3), c = 5.6056(11) A, β = 94.532(2)°, and Z = 4 for 2S, and a = 9.800(9), b = 7.950(7), c = 16.690(15) A, β = 100.890(12)°, and Z = 4 for 15S. The unit cell of 4S has a triclinic Pī symmetry with the cell parameters a = 6.0436(10), b = 8.7871(14), c = 15.535(2) A, α = 81.921(2)°, β = 81.977(2)°, γ = 80.889(2)°, and Z = 2. Compounds 9S and 11S both crystallize in the orthorhombic space group P212121, with a = 6.188(3), b = 8.041(4), c = 26.005(14) A, and Z = 4 for 9S, and a = 5.835(2), b = 8.010(3), c = 25.131(9) A, and Z = 4 for 11S. Twenty-four aryl sulfide compounds with different substituents were synthesized and characterized, and the molecular structures of six different sulfide compounds have been determined by single-crystal X-ray crystallography.

Ca2+ , a ubiquitous but nuanced modulator of cellular physiology, is meticulously controlled intracellularly. However, intracellular Ca2+ regulation, such as mitochondrial Ca2+ buffering capacity, can be disrupted by 1 O2 . Thus, the intracellular Ca2+ overload, which is recognized as one of the important cell pro-death factors, can be logically achieved by the synergism of 1 O2 with exogenous Ca2+ delivery. Reported herein is a nanoscale covalent organic framework (NCOF)-based nanoagent, namely CaCO3 @COF-BODIPY-2I@GAG (4), which is embedded with CaCO3 nanoparticle (NP) and surface-decorated with BODIPY-2I as photosensitizer (PS) and glycosaminoglycan (GAG) targeting agent for CD44 receptors on digestive tract tumor cells. Under illumination, the light-triggered 1 O2 not only kills the tumor cells directly, but also leads to their mitochondrial dysfunction and Ca2+ overload. An enhanced antitumor efficiency is achieved via photodynamic therapy (PDT) and Ca2+ overload synergistic therapy.

Intra-peritoneal adhesion are common and serious complications after surgery. Deposition of proteins and inflammatory response on injured cecum are main factors resulting in the formation of adhesi...

Regularly assembled structures of nanowires, such as aligned arrays, junctions and interconnected networks, have great potential for the applications in logical circuits, address decoders, photoelectronic devices and transparent electrodes. However, for now it is still lack of effective approaches for constructing nanowire bifurcated junctions and crosslinked networks with ordered orientations and high quality. Herein, we report the controlled growth of Bi2S3 semiconductor nanowire bifurcated junctions and crosslinked networks with well-aligned directions and high crystalline degree by utilizing the proportional lattice match between nanowires and substrates. Taking advantages of the “tip-to-stem splice” assembly of individual nanowires, the precise orientation alignments of Bi2S3 semiconductor nanowire bifurcated junctions and crosslinked networks were successfully realized. The controlled growth mechanism and structural evolution process have been elucidated by detailed atomic structure characterizations and modeling. The highly crystal quality and direct energy bandgap of as-assembled photodetectors based on individual bismuth sulfide nanowires enabled high photoresponsivity and fast switch time under light illumination. The three-terminal devices based on nanowire bifurcated junctions present rapid carrier transport across the junction. The flexible photodetectors based on nanowire crosslinked networks show very minimal decay of photocurrent after long-term bending test. This work may provide new insights for the guided construction and regular assembly of low-dimensional ordered functional nanostructures towards advanced nanotechnologies.

Most skarns are found near the pluton or in lithologies containing at least some limestone. However, recent research has shown that neither a pluton nor limestone is necessarily required to form a skarn deposit. The newly discovered Bagenheigeqier Pb–Zn skarn deposit is located in NE China. The skarn and Pb–Zn orebodies occur in volcanic lithologies of the Baiyin’gaolao Formation and are controlled by NE–SW-trending faults. The nearest pluton is a granite porphyry, at a distance of 20–250 m from the orebodies. Five paragenetic stages at Bagenheigeqier are recognized: (I) skarn; (II) oxide; (III) early sulphide; (IV) late sulphide; and (V) late quartz–calcite. The fluid inclusions from stages II to V homogenized at temperatures of 402–452, 360–408, 274–319 and 167–212°C, respectively. The hydrogen and oxygen isotope compositions (δ18OH2O, –12.4‰ to +9.3‰; δDH2O, –156.5‰ to –99.1‰) indicate that the ore-fluids were primarily of magmatic origin, with the proportion of meteoric water increasing during the progression of ore formation. Sulphur isotope values (δ34SVCDT, 1.4–5.5‰), lead isotope values (206Pb/204Pb, 18.184–18.717; 207Pb/204Pb, 15.520–15.875; 208Pb/204Pb, 37.991–38.379) and the initial 187Os/188Os ratios of the pyrite (0.307 ± 0.06) suggest that the ore metals were derived from the granite porphyry and Baiyin’gaolao Formation. Re–Os dating of pyrite intergrown with galena and sphalerite yielded a well-constrained isochron age of 151.2 ± 4.7 Ma, which is coeval with the laser ablation – inductively coupled plasma – mass spectrometry zircon U–Pb age of 154 ± 1 Ma for the granite porphyry. The deposit was therefore formed during Late Jurassic time.

Anti-Mullerian hormone (AMH) acts in maintaining orderly cyclic recruitment of early follicles, suggesting that it is a promising candidate for influencing animal reproductive efficiency. This study aimed to elucidate the effect of a missense mutation of Val566Ile on the structure of AMH protein and the genetic association of Val566Ile and AMH expression with egg production in chickens. Structural perturbations of Val566Ile were predicted by homology modeling. The association of the variant with the number of eggs was tested using a quantitative trait transmission disequilibrium test model. AMH expression in granulosa cells in Lueyang black-boned chickens was compared with that in Nick chickens. The Val566 of AMH is a non-conservative amino acid among mammals and birds, but its hydrophobicity is completely conservative. The substitution of Val566 for Ile566 potentially disrupted hydrogen bonds and solvent accessibility of 22 residues and created a short α-helix in the C terminus of AMH. Despite having striking structure-disrupting potential, the variant was not statistically associated with the number of eggs (P>0.05) in the Lueyang black-boned chickens. We did not detect differential expression of AMH between Lueyang black-boned chickens and Nick chickens (P>0.05). These results confirmed the structural impact of Val566Ile, but suggested that Val566Ile and AMH expression might not be the major genetic determinants for egg production in Lueyang black-boned chickens.

This paper presents a differential microwave microfluidic sensor based on the microstrip complementary split-ring resonator (MCSRR) structure for liquid characterization. At the resonance, the electric field concentrates along the slot, where the microfluidic channel is located. As the liquid sample is injected, the corresponding reflection coefficient is changed, while the reference response is unaffected. The relative permittivity and loss tangent of the liquid can be extracted from the variations in the resonant frequency and quality factor. A prototype of the proposed sensor is fabricated and measured for functionality validation. The proposed sensor exhibits a high sensitivity of 0.626% on average and is capable of suppressing unwanted environmental influences.

Cost-effective nitrogen-doped monolithic hierarchical carbon cryogels with excellent mechanical properties and carbon dioxide (CO2) adsorption performance were prepared from phenol, melamine, and formaldehyde (PMF) by the sol-gel, freeze-drying, and then, pyrolysis processes under an inert atmosphere. The morphology, mechanical properties, pore structure, and chemical characteristics of these cryogels were investigated. The results showed that the dilution ratio played a crucial role in the preparation of nitrogen-doped PMF carbon cryogels with controlled structures. The prepared carbon cryogels were a kind of monolithic materials composed of a hierarchical pore structure and had high compression properties (0.67 and 9.4 MPa for strength and modulus), porosity (97.6%), surface area (1406 m2/g), and heteroatom nitrogen content (0.98-2.09%). CO2 adsorption capacities up to 5.75 mmol/g at 0 °C and 4.50 mmol/g at 25 °C under 1 bar were obtained, which is at a high level among N-doped carbon materials and far better than resorcinol-based carbon gels reported. These superior CO2 adsorption capacities, high isosteric adsorption heat (Qst), and good CO2/N2 adsorption selectivity were ascribed to the synergistic effect of high surface area, appropriate pore size, and also heteroatom doping.

[Image: see text] Two novel compounds were identified as Naa50 binders/inhibitors using DNA-encoded technology screening. Biophysical and biochemical data as well as cocrystal structures were obtained for both compounds (3a and 4a) to understand their mechanism of action. These data were also used to rationalize the binding affinity differences observed between the two compounds and a MLGP peptide-containing substrate. Cellular target engagement experiments further confirm the Naa50 binding of 4a and demonstrate its selectivity toward related enzymes (Naa10 and Naa60). Additional analogs of inhibitor 4a were also evaluated to study the binding mode observed in the cocrystal structures.

Camellia oleifera Abel. is a cultivable plant with important economic value. It is very helpful for the scientific utilization, cultivation and preservation of germplasm resources through evaluating the genetic diversity. In this study, we estimated the genetic distances of 135 accessions of C. oleifera using ISSR and SCoT markers, respectively. The genetic dissimilarity coefficients of ISSR markers ranged from 0.56 to 1.00. And the accessions were divided into five groups. While the genetic dissimilarity coefficients of SCoT markers ranged from 0.62 to 1.00, the accessions were divided into four groups. The results demonstrated that C. oleifera germplasms perform a little genetic variation. This is the first report to evaluate the genetic diversity of different C. oleifera germplasms using the ISSR and SCoT molecular markers, and the results provide the useful foundation for plant breeding of C. oleifera.

Four microporous mullite-corundum refractory aggregates were prepared from Al(OH)3 and kaolinite gangue through an in-situ decomposition synthesis technique. The effect of the compacting pressure (30–150 MPa) on the microstructure and strength were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The higher compacting pressure limited the rearrangement of Al(OH)3 pseudomorphs during the reaction sintering process and promoted the reaction between Al(OH)3 and kaolinite gangue, leading to the formation of closed mullite layers on the surface of Al(OH)3 pseudomorphs. The pore size distributions of all four microporous aggregates were bimodal with closed pores (0.1–1.0 μm) located inside of the Al(OH)3 pseudomorphs, whereas open pores (1.0–10.0 μm) were found between the pseudomorphs. When the compacting pressure was 150 MPa, the microporous mullite-corundum refractory aggregates had a high total porosity of 40.5%, a highly closed porosity of 16.2%, median pore size of only 0.74 μm as well as an excellent compressive strength of 103.2 MPa.

In order to clarify the effect of graphite content on the corrosion behavior of MgO–C refractories immersed in MnO-rich slag, the MgO–C refractory samples bearing 5 wt%, 10 wt% and 15 wt% graphite were prepared, and exposed in the slag composed of 40 wt% CaO, 40 wt% SiO2 and 20 wt% MnO. The results show that metallic Mn particles and (Mg,Mn)O solid solution are formed at the slag/refractories interface. Whereas, no dense layer is formed by (Mg,Mn)O solid solution at the interface. The decrease in MnO content of slag is mainly attributed to the reaction with graphite to form liquid Mn. The graphite is found in the slag, and dissolved in the form of oxidation. The poor wetting limits the contact area of graphite and slag, reducing graphite oxidation and decarburized area. The graphite does not become the passage for slag to penetrate into the refractories due to the oxidation. On the contrary, the dissolution of MgO in slag is faster than graphite, thus is mainly responsible for the degradation of refractories. As a result, MnO and MgO contents change less in the slag contacted with the refractories bearing higher graphite content.

Defects in the zeolite layer restricts the applications of the zeolite membrane. In this study, we found that the bubbles in the synthesis solution and the interface between the support and the synthesis solution impeded the movement of the Si/Al active ingredients to the surface of the support during the membrane synthesis process, leading to the formation of defects. Accordingly, we pre-degassed the synthesis solution containing 170-mm-long ceramic tube supports under a vacuum of 0.1 MPa at room temperature before the membrane synthesis. The characterization results showed that the degassing pretreatment drove out the gases in the synthesis solution and the interface between the synthesis solution and the support, and thus eliminated pinhole defects in the zeolite layer. The permselectivity of H2 over C3H8 increased from 8.8 to 20.2 when the synthesis solution was degassing pretreated. In conclusion, the degassing pretreatment clearly eliminated the defects in the membrane.

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a family of recently discovered lipids with important physiological functions in mammals and plants. However, low detection sensitivity in negative ionization mode mass spectrometry makes low-abundance FAHFA challenging to analyze. A 2-dimethylaminoethylamine (DMED) based chemical derivatization strategy was recently reported to improve the MS sensitivity of FAHFAs by labeling FAHFAs with a positively ionizable tertiary amine group. To facilitate reliable, high-throughput, and automatic annotation of these compounds, a DMED-FAHFA in silico library containing 4290 high-resolution tandem mass spectra covering 264 different FAHFA classes was developed. The construction of the library was based on the heuristic information from MS/MS fragmentation patterns of DMED-FAHFA authentic standards, and then, the patterns were applied to computer-generated DMED-FAHFAs. The developed DMED-FAHFA in silico library was demonstrated to be compatible with library search software NIST MS Search and the LC–MS/MS data processing tool MS-DIAL to guarantee high-throughput and automatic annotations. Applying the in silico library in Arabidopsis thaliana samples for profiling FAHFAs by high-resolution LC–MS/MS enabled the annotation of 19 DMED-FAHFAs from 16 families, including 3 novel compounds. Using the in silico library largely decreased the false-positive annotation rate in comparison to low-resolution LC–MS/MS. The developed library, MS/MS spectra, and development templates are freely available for commercial and noncommercial use at https://zenodo.org/record/3606905.

Vanadium (V) pollution in soil has been widely noted, while knowledge about the effect of soil colloid on migration of V is scarce. Batch adsorption-desorption and transportation of the colloid-adsorbed V in columns packed with quartz sand under various environment conditions were carried out to explore the retention and transportation of V by colloidal kaolinite. Batch adsorption-desorption studies show that the adsorption of V by the colloidal kaolinite was mainly specific adsorption and redox played a limited role in the adsorption process. The maximum adsorption capacity of the colloidal kaolinite was 712.4 mg g−1, and about 5.9–8.7% of the adsorbed V could be desorbed. Both the adsorption-desorption and migration of V with colloidal kaolinite were highly ambient condition dependent. The column studies show that V was highly mobile in the saturated porous media. An easier transfer of V with an increase in pH, IS, and velocity of flow was noted. However, the increase of IS lead to the blockage of the colloidal kaolinite transportation. The recovery rate of the colloidal kaolinite at pH 7 and 9 was 2.0 and 2.1 times that at pH 5, respectively. The migration of colloidal-adsorbed V in sand column preceded that of V ion, but more colloidal-bound V than V ion remained in the column. Lack of consideration of the combination and co-transportation of V and colloidal kaolinite will lead to an overestimation of the risk of V to deeper soil profiles and groundwater.

Metal-organic frameworks (MOFs) with zeolitic structure process fantastic structural metrics and display excellent applications in many aspects; however, they are difficult to assemble. Herein, on the basis of a tetrahedral Zn

The resistive random access memory with a graphene electrode (GE) is carefully modeled and simulated by considering its geometrical and physical properties. Since the graphene oxide is generated through the migration of oxygen ions from metal oxide to GE affecting current transport in the memory cell, the model of its electrical conductivity with different oxidation degrees is developed, in which the conductivity is exponentially dependent on the oxidation degree. The simulated ${I}$ – ${V}$ characteristics, which agree well with those of the experiment, are obtained by self-consistently solving the current transport, heat conduction, and oxygen vacancy migration equations. Based on the simulation, oxygen vacancy density, temperature distribution, and resistances of high- and low-resistance states are extracted and compared. A low-temperature increase due to low power consumption indicates its great potential for high-density integration.

In this study, a new mullite-foamed ceramic, reinforced with in-situ SiC whiskers (MCS) and applied as the insulating lining of thermal equipment used in cement production, was investigated. Compared with a conventional mullite-foamed ceramic (MC), the MCS phase composition, microstructure, compressive strength, thermal conductivity and alkali corrosion resistance were investigated by using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and Factsage® software. The results showed that after being fired in granular coke, the SiC whiskers formed into MCS struts and were distributed in the pores between the interconnected needle-like mullite. Although the formation of SiC with higher conduction slightly increased MCS thermal conductivity, it significantly enhanced the compressive strength and alkali corrosion resistance of the foamed ceramic. Compared with the MC, although the MCS had higher bulk density (3.9%), and higher thermal conductivity (9.5% at 800 °C), it was more important that greatly improved compressive strength (by 60%) and better alkali corrosion resistance was achieved.

In this study, four zircon granules are prepared by using granulation method and using TiO2 and sodium carboxymethyl cellulose (CMC) as a sintering additive and binder, respectively. Then, the effects of TiO2 addition on phase composition, pore size distribution and sintering process are analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results reveal that only a small portion of zircon is decomposed into ZrO2 and SiO2 after sintered at 1250 °C, however, the zircon granules consist of zircon, ZrTiO4 and mullite after sintering at 1550 °C. In general, the addition of TiO2 accelerated the sintering process, promoted the migration rate of grains and transformed the apparent pores into closed pores, resulting in decreased pore size and enhanced compressive strength. The zircon granule, with 2.0 wt% TiO2, rendered an optimal apparent porosity of 24.0%, a high closed porosity of 8.35%, a high cylinder compressive strength retention rate of 44.9% and a relatively homogeneous pore size distribution after sintering at 1550 °C.

In this paper, a double-side grinding method with variable position rotation is proposed, which changes the motion mode of the workpiece in the fixed distance rotation grinding from the grinding principle, and realizes the irregular planar motion of the workpiece in the isolation dics at the same time as the rotation. That is, the movement trajectory of the workpiece rotation center relative to the grinding tool is the curve of the change. Different grinding principles fundamentally overcome some defects of traditional planar grinding methods. A prototype model of variable position rotation grinding is established, and the feasibility of the new method is verified by simulation experiments. The simulation data also further proves the time-varying nature of this grinding method in improving the grinding trajectory, the uniformity of relative velocity distribution of grinding and the superiority and diversity of the mechanical wear of the grinding mechanism and the ability to adjust the grinding trajectory.

A hybrid of dearomatized isoprenylated acylphloroglucinol (DIAP) and monoterpenoid, hypatone A (1), together with its biosynthetic analogues 2-4 is characterized from Hypericum patulum. Structurally, 1 possesses an unprecedented spiro[bicyclo[3.2.1]octane-6,1'-cyclohexan]-2',4',6'-trione core as elucidated by extensive spectroscopic and X-ray crystallographic analyses. Biological studies reveal that compounds 1 and 2-4 produce opposite effects on Cav3.1 low voltage-gated Ca2+ channel, with 1 and 4, respectively, being the most potent Cav3.1 agonist and antagonist from natural products. Further studies suggest that compound 1 and its biogenetical precursor, 2, have the same binding site on Cav3.1 and that the rigid cagelike moiety at C-5 and C-6 is a key structural feature responsible for 1 being an agonist. Furthermore, 1 can normalize the pathological gating of a mutant Cav3.1 channel found in spinocerebellar ataxia 42 (SCA42), a hereditary neurodegenerative disorder with no available therapy. Collectively, our findings provide valuable tools for future studies on Cav3.1 physiology and pathophysiology, as well as afford possible leads for developing new drugs against SCA42, epilepsy, and pain.

The influence of past variations in water column denitrification (WCD) in the eastern tropical Pacific (ETP) on the western tropical Pacific (WTP) remains ambiguous, due to the deficiency of enough down-core records of nitrogen isotope (δ15N) in the WTP. In this study, sedimentary δ15N record down a core from the northern WTP is investigated to revisit this issue. After elucidating the potential presence of multiple forms of N by analyzing bulk parameters and the potential occurrence of alteration by examining amino acids, the bulk sedimentary δ15N can be accepted as an available indicator of nitrate δ15N. Further, a comprehensive comparison of δ15N records in the North Pacific reveals largely similar variations from the last glacial maximum to early Holocene, suggesting a common feature of WCD signals associated with basin-scale processes, likely as a consequence of basin-wide ocean circulations. Our result suggests that the signals of local N2 fixation in the western Pacific marginal seas would have been constrained by a synchronous glacial-interglacial change of the source WCD signals.

Vanadium (V) is a toxic metal, which dominantly exists as V5+ in an aquatic environment. Rice straw, which is an abundant agricultural by-product throughout China was used to treat V5+ containing w...

Design considerations of vertically stacked horizontal nanosheet (NSH) gate-all-around pMOSFETs are examined at the sub-5-nm technology node using in-house-developed non-equilibrium Green’s function (NEGF) quantum ballistic transport simulator. In the individual Si and Ge NSHs, ON-state current and subthreshold swing are evaluated and analyzed for different crystal orientations and various sheet widths. Performance benchmarking of the stacked FET arrays at the iso-footprint is accomplished to explore the roles of sheet configurations further with stack number and sheet spacing changed. It is found that the benefit of the larger effective channel width provided by the wider NSH is always compromised by degraded gate control, especially in the Ge channel. [111] and [100] are shown to be the best transport orientations for individual Si and Ge NSHs, respectively. However, [100] channel vertically confined along [011] shows greater potential for the applications of wider Si and Ge NSHs in the stacked FET array. The process-induced NSH width variation is studied statistically, and it is shown to cause significant performance fluctuations in the stacked array consisting of wide Si or narrow Ge NSHs.

The rapid development of the flexible electronics industry places higher demands on the performance of flexible ferroelectric memories. In practical work, environmental factors such as high temperature, radiation and humidity may also affect the lifetime of flexible devices besides electric field and bending stress. In this paper, Hf0.6Zr0.4O2 (HZO) ferroelectric thin film with excellent ferroelectric properties and high reliability was prepared on flexible mica substrate by atomic layer deposition (ALD). More importantly, the flexible HZO ferroelectric films maintain superior ferroelectricity, retention and fatigue endurance under multiple harsh conditions. On the basis of multi-service conditions, this work marks an important step in the development of new flexible HfO2-based ferroelectric memories from fundamental research to practical applications.

Carbon-containing Al2O3 refractory crucibles and pure Al2O3 refractory crucible were fabricated to study the effect of carbon-containing Al2O3–C refractories on aluminum and carbon pick-up of iron. Refractory crucibles with pure iron powder were placed in a vacuum induction furnace and heated at 1600 °C for regular time under flowing argon atmosphere. The Al and C contents of iron samples were analyzed, and iron samples were also investigated using a field scanning electron microscope equipped with energy-dispersive spectroscope. The results showed that carbon materials did affect the interaction of (Al2O3–C)/Fe system, carbothermal reduction in alumina occurred in the reaction system and the extent of reactions depended on the kinds of carbon materials.

We propose and demonstrate experimentally a scheme for simultaneously generating multi-channel broadband chaotic signals based on two unidirectionally coupled weak-resonant-cavity Fabry-Perot laser diodes (WRC-FPLDs) with almost the same mode interval, where one WRC-FPLD is utilized as master WRC-FPLD (M-WRC-FPLD) and the other is used as slave WRC-FPLD (S-WRC-FPLD). Under the optical injection from the M-WRC-FPLD with suitable injection parameters, multiple longitudinal modes of the S-WRC-FPLD can be simultaneously driven into chaotic states, which can provide multi-channel chaotic signals. Via a tunable optical filter, we inspect the performances of 9-channel chaotic signals, the results show that the chaotic bandwidths are within the range of 8∼15 GHz for all the 9-channel chaotic signals. Furthermore, the influences of the injection power and frequency detuning on the performances of the chaotic output from one of the channels are also analyzed.