In order to optimize the degradation of high-concentration aniline wastewater, the operation of sequencing batch bioaugmentation reactors with different aniline concentrations (200 mg/L, 600 mg/L, 1000 mg/L) was studi...
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In order to optimize the degradation of high-concentration aniline wastewater, the operation of sequencing batch bioaugmentation reactors with different aniline concentrations (200 mg/L, 600 mg/L, 1000 mg/L) was studied. The results showed that the removal rates of aniline and cOD in the three reactors could reach 100%. When the aniline increased to 600 mg/L, the nitrogen removal efficiency reached the peak (51.85%). The increase of aniline inhibited the nitrification, while denitrification was enhanced due to the increase of c/N ratio. But this change was reversed by the toxicity of high concentrations of aniline. The metagenomic analysis showed that when the aniline concentration was 600 mg/L, the abundance distribution of microbial samples was more uniform. The improved of aniline concentration had led to the increase of aromaticcompounds degradation metabolic pathways. In addition, the abundance of aniline degradation and nitrogen metabolism genes (dmpB, xylE, norB) was also promoted.
An explicit analytical model for predicting the heat transfer in c/Siccomposite pyramidal lattice core sandwich structures is proposed with considering the radiation emitted from the struts. Temperature gradient in t...
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An explicit analytical model for predicting the heat transfer in c/Siccomposite pyramidal lattice core sandwich structures is proposed with considering the radiation emitted from the struts. Temperature gradient in thickness direction of the lattice core sandwich structures is considered in the proposed model. The predictions are compared with the published experimental data and analytical results. It indicates the effect of the radiation emitted from the struts on the equivalent thermal conductivity becomes more significant at high temperature and cannot be overlooked. The present model is more accurate in estimating the high-temperature equivalent thermal conductivity of pyramidal lattice core sandwich structures than those models without considering the radiation of struts. The effects of geometry, solid emissivity, and temperature on the equivalent thermal con-ductivity of pyramidal lattice core sandwich structures are well discussed.
Magnetic metal/carbon composites derived from metal-organic frameworks (MOFs) have shown tremendous potential for lightweight electromagnetic (EM) wave absorption. In this study, 1, 3, 5-trimethylbenzene (TMB) and dop...
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Magnetic metal/carbon composites derived from metal-organic frameworks (MOFs) have shown tremendous potential for lightweight electromagnetic (EM) wave absorption. In this study, 1, 3, 5-trimethylbenzene (TMB) and dopamine (DA) are used to regulate the morphology of bimetallic MIL-53. Afterwards, the morphology of MIL-53 rods changes to spindles. The corresponding derivative of Feco/ccomposite with spindle microstructure reveals better microwave absorption properties than MIL-53 rods derived Feco@Fe3c/ccomposite. The high specific surface area, strong attenuation ability and good impedance matching give desirable EM waves absorption performance of Feco/ccomposite. The strongest absorption intensity is - 78.6 dB with effective absorbing bandwidth of 5.1 GHz when the matching thickness is 2.6 mm. This work provides a new idea for the modification of MOFs derivatives.(c) 2022 Elsevier B.V. All rights reserved.
In order to find a good friction pair for the finger seal, the pin-on-disc friction tests matching the actual working conditions of finger seal are designed based on the performance simulation of finger seal and the s...
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In order to find a good friction pair for the finger seal, the pin-on-disc friction tests matching the actual working conditions of finger seal are designed based on the performance simulation of finger seal and the similarity principle of PV value, in which the friction characteristics between pins with two different materials (c/ccomposite or cobalt-base alloy GH605) and discs with two different coatings (cr3c2 or Al2O3) are tested and analyzed respectively;the test results show that the wear loss of all the friction pairs increases with the load increasing, but the friction coefficient of the c/ccomposite pin (no matter contacting with cr3c2 or Al2O3 coating) is much less than that of GH605 pin;in the four kinds of friction pairs, the c/c-cr3c2 pair has the greatest friction characteristics and least wear loss. Then, to verify the application feasibility of c/ccomposite in the finger seal further, the bench-scale performance test of the finger seal with c/c-cr3c2 pair (the finger seal is made of c/ccomposite, and the rotor surface is coated with cr3c2) is carried out with a self-developed testing rig;according to the leakage and wear results before and after the durability test lasted for 60 h, there is little distinct trace of destruction on the friction surfaces of finger seal with c/c-cr3c2 pair after the durability test, which is in good agreement with the result of pin-on-disc friction test;besides, after the durability test, the static leakage of finger seal with c/c-cr3c2 pair becomes lower than that before and is lower than that of finger seal made of GH605. The test results in this paper indicates that the c/c-cr3c2 pair has nice friction characteristics and can be a good choice for the friction pair of the finger seal.
To achieve effective antioxidation of on-site repair coating for c/c brake materials in the full temperature range (500-900 degrees c), lead glass and bismuth glass were introduced into the borosilicate glass to acqui...
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To achieve effective antioxidation of on-site repair coating for c/c brake materials in the full temperature range (500-900 degrees c), lead glass and bismuth glass were introduced into the borosilicate glass to acquire the protective coatings. Before preparing coating samples, the thermal gravity characteristics of the lead/bismuth-borosilicate glass powders were analyzed by TG/DSc. The results revealed that the temperature at which weight gain begins was 495 degrees c and 545 degrees c, respectively. The oxidation behaviors of the lead- and bismuth-modified borosilicate glass coatings were compared at 500 degrees c, and the antioxidation properties of the former were further examined from 500 to 900 degrees c. The oxidation results indicated that mixing lead glass with borosilicate glass realized effective oxidation resistance in the full temperature range. With a lead content of 20%, the lead-borosilicate glass coating was able to protect c/c substrates from oxidation. The corresponding weight loss of the lead-glass-coated samples was -1.89% when oxidized at 500 degrees c for 10 h, while the weight loss was -2.55% when further oxidized at 900 degrees c for 10 h. However, mixing bismuth glass with borosilicate glass was difficult to achieve the oxidation resistance of the coating at 500 degrees c due to the significant phase separation.
To realize the high-strength bonding of c/ccomposites and metal Mo, Ti was utilized to modify the BNi-5 filler by controlling the interfacial defects. As 5 wt% Ti was used to modify the filler, the doped Ti could abs...
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To realize the high-strength bonding of c/ccomposites and metal Mo, Ti was utilized to modify the BNi-5 filler by controlling the interfacial defects. As 5 wt% Ti was used to modify the filler, the doped Ti could absorb the surrounding Mo atoms and prevent them from reacting with liquid Ni-based filler to form MoNiSi compounds in the carbon-side interfacial region during the joining process, reducing the consumption of liquid filler at the interfacial area. Thus, the sufficient liquid filler offers the necessary formation conditions for a dense interfacial layer without obvious defects like pores, increasing shear strength from 19.56 to 45.80 MPa. Excess Ti would have a negative effect on the joint strength since numerous brittle Tic would be produced to form new defects in the interfacial layer, and the high-performance MoNiSi ternary compounds in the interlayer were restrained due to the formation of brittle Ni-Ti-Si compounds with a big size. This work provides an effective strategy to significantly enhance joint strength by controlling the interfacial defects.
The (Z)-4-aryliden-2-(2-acetoxyphenyl)-5(4H)oxazolones 1a-1c react with H2SO4 to give the corresponding (Z)4-aryliden-2-(2-hydroxyphenyl)-5(4H)oxazolones *** molecular structures of 1c and 2a have been determined by X...
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The (Z)-4-aryliden-2-(2-acetoxyphenyl)-5(4H)oxazolones 1a-1c react with H2SO4 to give the corresponding (Z)4-aryliden-2-(2-hydroxyphenyl)-5(4H)oxazolones *** molecular structures of 1c and 2a have been determined by X-ray diffraction methods, and show planar skeletons. Oxazolones 2a-2c are potential c,N,Otridentate ligands towards transition metals, and their molecular design obeys to the search of a rigid environment around the metal. The reaction of Pd(OAc)2 with oxazolones 2a-2c (1:1 M ratio) in cF3cO2H or NcMe as solvents results in the synthesis of diverse complexes (3-7). As a function of the reaction conditions, two different bonding modes have been characterized: N,O-chelate in the dinuclear complexes [Pd(kappa 2-N,O-2b,c)(mu -O2ccF3)]2 (3b,c), as a result of the N-coordination and deprotonation of the hydroxy group;and c,N,Otridentate in mononuclear complexes [Pd(kappa 3-c,N,O-2a,b)(L)] (L = cF3cO2H 4a,b;dmso-d6 5a,b;NcMe 6b;pyridine 7b), obtained after N-bonding, OH deprotonation and c-H bond activation. All complexes have been fully characterized by HRMS and NMR methods, showing the high stability of the c,N,O-tridentate bonding mode.
As the anode material of sodium-ion batteries (SIBs), TiO2 exhibits low sodium storage potential and small structural changes in the sodium storage process. To improve the pseudocapacitive behavior of TiO2, PPy was us...
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As the anode material of sodium-ion batteries (SIBs), TiO2 exhibits low sodium storage potential and small structural changes in the sodium storage process. To improve the pseudocapacitive behavior of TiO2, PPy was used as an N-containing carbon source to modify TiO2/c (Tc) porous nanofibers. PPy-derived carbon (Pc) nanoparticles anchored on Tc nanofibers (PcTc) by a simple chemical oxidation method. The Pc nanoparticles significantly improved the electrical conductivity of PcTc nanofibers with oxygen vacancies (OVs), while substantially improving the structural stability. As a result, PcTc exhibits a high reversible speci-ficcapacity (179.8 mAh/g at 1.0 A/g) and a very long cycle life (206.4 mAh/g after 1000 cycles at 1.0 A/g) when used as anodes of SIBs. The superior sodium storage performance of PcTc nanofibres is attributed to the special structure with N-doping and OVs, resulting in high pseudo-capacitance contribution (95 %, 2.0 mV s-1). This OVs-creating approach can improve the pseudocapacitance of oxide anodes for sodium storage.
The hydroxyapatite (HA) coating on carbon/carbon (c/c) is reasonable and feasible to obtain bone graft materials with appropriate mechanical and biological properties. However, improvement of the physical and chemical...
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The hydroxyapatite (HA) coating on carbon/carbon (c/c) is reasonable and feasible to obtain bone graft materials with appropriate mechanical and biological properties. However, improvement of the physical and chemical properties of HA-c/ccomposites to promote bone regeneration and healing remains a challenge. In our present study, the HA coatings on c/c with magnesium (Mg) (Mg-HA-c/c) composites were synthesized that ca (NO3)(2), Mg (NO3)(2), and NH4H2PO4 were mixed and coatings were made by electromagnetic induction deposition's heating. As determined with in vitro experiments, Mg-HA-c/ccomposites containing 10 and 20% Mg decreased miR-16 levels, increased cell viability, elevated the levels of osteogenesis-related genes, and promoted osteogenic differentiation of bone marrow mesenchymal stem cells (BMScs) seeded on their surfaces. In a rat model of skull defects, compared to the control group, at 4 and 12 weeks after the operation, the bone volume fraction (BV/TV) of Mg-HA-c/ccomposite group was increased by 8.439 +/- 2.681% and 23.837 +/- 7.845%, as well as the trabecular thickness (***) was 56.247 +/- 24.238 mu m and 114.911 +/- 34.015 mu m more. These composites also increased the levels of ALP and RUNX2 in skull. The Mg-HA-c/ccomposite-enhanced bone regeneration and healing were blocked by in situ injection of an miR-16 mimic lentivirus vector. Thus, Mg-HA-c/ccomposites promote osteogenic differentiation and repair bone defects through inhibiting miR-16.
The Nicr-cr3c2-caF2/BaF2 coating with the NiAl bond coating was sprayed on a Ni16cr13co4Mo(wt%) alloy by detonation-gun spray, and hot corrosion behaviors were studied by electrochemical measurements. In molten Nacl-K...
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The Nicr-cr3c2-caF2/BaF2 coating with the NiAl bond coating was sprayed on a Ni16cr13co4Mo(wt%) alloy by detonation-gun spray, and hot corrosion behaviors were studied by electrochemical measurements. In molten Nacl-Kcl, the corrosion products were mainly cr2O3. Gas phases such as cl2 led to spallations and cracks on the coating surface. In molten Nacl-Na2SO4, Na2SO4 decomposed and reacted with the coating. Mixed oxides formed a continuous corrosion layer, and Al diffused outward from bond coating to be oxidized. Some liquid phases existed in the corrosion layer and promoted hot corrosion. The detailed hot corrosion mechanisms in two molten salts were discussed.
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