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In this study, the crude polysaccharides (CSVP) and the preliminary purified polysaccharides (PSVP) from Sanghuangporus vaninii were obtained. The physicochemical properties, gastrointestinal digestion, and probiotic fermentation behaviors of CSVP and PSVP as well as the immunomodulatory effects of PSVP in cyclophosphamide-treated mice were investigated. The results showed that PSVP had higher total polysaccharides content and solubility, but lower radical scavenging activity than CSVP. Moreover, PSVP showed lower hydrolysis degree and better probiotic effects than CSVP. In immunosuppression mice model, PSVP supplement increased the body weight, spleen and thymus index, improved the release of cytokines IFN-γ, immunoglobulins IgM and IgG, and enhanced the lysozyme activity. Moreover, PSVP supplement significantly prevented the oxidative stress in vivo, increased the level of beneficial gut microbiota, especially Bacteroidaceae and Lactobscillsceae, as well as the content of short-chain fatty acids (SCFAs). These results indicated that PSVP could recover the immune response in cyclophosphamide-treated mice by regulating gut microbiota and intestinal barrier. The findings will lay a theoretical foundation for equitable utilization of S. vaninii resources as well as the product development.

A novel high-entropy material, (Y0.2Gd0.2Er0.2Yb0.2Lu0.2)2Zr2O7 was successfully synthesized by the solid state reaction method and spark plasma sintering, and investigated as a promising thermal barrier coating material. Rare-earth elements were distributed homogeneously in the pyrochlore structure. It was found that the prepared high-entropy ceramic maintains pyrochlore structure at the temperature up to 1600 °C, and it possesses a similar thermal expansion coefficient (10.2 × 10−6 K−1 at 25-900 °C) to that of YSZ, low thermal conductivity (

The preparation of MgO-stabilized ZrO2 powders was based on combustion synthesis between Mg powders and CO2 with ZrO2 powders as the diluent. The effects of the diluent content on the combustion process parameters, phase composition, microstructure, and high-temperature stability were systemically investigated. As the diluent content increased, the reaction temperature, propagation velocity, and MgO content decreased. The reactant powders underwent different reaction processes and were transformed into different phase compositions due to the change in diluent content. The obtained MgO-stabilized ZrO2 powders exhibited excellent high-temperature stability up to 1400 °C.

Alkali/surfactant/polymer (ASP) combines the advantages of each of the chemical in the blend. ASP has shown to be an effective and practical method to enhance oil recovery. Compared with vertical wells, fluid flooding by using horizontal wells is believed to be infeasible due to easier fluid breakthrough and subsequent low sweeping efficiency. However, good responses observed in field applications (Daqing oil field, China) show the promising future of ASP flooding using horizontal wells. In this study, a combination of laboratory-scale core displacement experiments and reservoir-scale numerical simulations was used to study the performances of ASP flooding by using horizontal injection/production wells and vertical injection/production wells to reveal the mechanisms responsible for the favorable responses observed in the field. Firstly, displacement experiments in evaluation of ASP flooding using vertical wells and horizontal wells were conducted. The effects of well type on ASP flooding performances were further evaluated by numerical simulation based on a realistic reservoir. The results show that, horizontal well injection/production pattern facilitates a better oil displacement performance due to the higher sweeping volume. This is because horizontal injection/production pattern weakens both the effects of surface heterogeneity and vertical inter-layer heterogeneity during ASP flooding performance. Although horizontal injection/production well pattern is not suitable for water flooding due to the higher chances for water breakthrough, the profile-control characteristic of ASP system blocks the high permeable channels to some extent, providing a better performance in combination with horizontal injection/production well pattern. This work systematically studied the effects of well type on ASP flooding performance at core scale and reservoir scale, and it provides theoretical and practical implications for the application of ASP flooding in enhancing oil recovery for high water cut reservoirs.

Glucose and ball-milled α-Al2O3 mixed powder was hydrothermal treated to synthesize Al2O3/C mixture, which was directly heated to 1700–1750 °C for 10 min holding in N2. Fine and single phase AlON powders were successfully fast prepared by one-step carbothermal reduction and nitridation (CRN). With aggregation of as-purchased α-Al2O3 being effectively disconnected by ball milling, α-Al2O3 particles were perfectly coated with carbon by hydrothermal treatment, which inhibited coalescence of Al2O3 during heating and enabled fast formation of AlON to further shorten holding duration. As a result, one-step fast fabricated pure AlON powder has fine primary particles with weak interconnections. At 170 rpm, powders were ball-milled to D50 ≤ 1.00 μm for 4 h, and D50 = 0.33 μm for 24 h. Moreover, primary particle size is controllable by adjusting holding time, synthesis temperature and heating speed. One-step CRN method provides a practical way to prepare pure AlON powder with the required primary particles.

Asymmetric ceramic membranes with disordered layer prepared by directional freeze-casting can be used as filter materials. However, there are few research achievements on the structural and permeability of disordered layers. Here, we obtained alumina asymmetric ceramic membranes with different disordered layer by adjusting the amount of alumina in the ceramic slurry. The results show that there are two kinds of structures in the disordered layer: spherical micropores and interconnected meshy pores, which lead to the change of airflow state. With the increase of the alumina content, the pore size of the disordered layer decreases and the network structure becomes complex, resulting in the decrease of the velocity of the inertial flow. The filter resistance of disordered layer increases obviously, but its proportion in the total filter resistance increases first and then decreases. The permeability is related to the pore size, specific surface area and channel complexity of the membrane.

Porous β-Si3N4 ceramics were prepared by combustion synthesis using Si, α-Si3N4 and Y2O3 powders as raw materials. The effects of α-Si3N4 diluent content in pellet on nitriding rate, shrinkage, porosity and flexural strength of porous ceramics were investigated. The results show that porous β-Si3N4 ceramic with porosity of 49 % and flexural strength of 151 MPa can be obtained by combustion synthesis when the content of α-Si3N4 diluent in raw materials is equal to that of Si, and the linear shrinkage of porous ceramic is only 2.8 %. In addition, the porous ceramic can be drilled and turned by WC drill and turning tool respectively.

The anisotropy of compression response and energy absorption of fiber enforced porous ceramics by directional freeze-casting have been investigated to infer the failure mechanism. An enhanced porous ceramic structured with fiber-bridging-lamellar walls was synthesized by directionally freezing nano spherical alumina suspension with different fiction of alumina microfibers. Due to the anisotropic microstructure, the mechanical properties of the freeze-casting ceramics are closely related to the orientation of the applied stress. Different orientations of loads correspond to the different deformation mechanisms under the load. The compression experiments under different orientations were carried out, and the failure mechanism was judged by the energy absorption characteristics and compression response. In contrast to traditional freeze-casting ceramics, the scaffolds supported with fiber bridges have higher mechanical properties (up to 15 MPa in compressive strength and density up to 0.76 g/cm3), and their failure behavior tends to plastic fracture, which increases toughness and availability without decreasing porosity and pore size.

Er3+/Yb3+ co-doped SrGdAlO4 up-conversion phosphors with a tetragonal phase were synthesized using solid state reaction method. The dominant up-conversion luminescent mechanism was deduced through analyzing the power dependencies, energy diagrams and fluorescence lifetimes. It is interesting that the emitting color was almost unchanged when adjusting the dopant contents of Er3+ and Yb3+, excitation power and ambient temperature. The emission intensity and color purity of SrGdAlO4: Er3+, Yb3+ sample can be notably enhanced by introducing Bi3+ ions. X-ray diffraction and band gap analysis illustrated that Bi3+ ions can increase the asymmetric surrounding environment of the SrGdAlO4 host lattice. Simultaneously, the change of microstrain value showed that the host crystalline is affected by Bi3+ ions codoping. Optical temperature sensing performance based on the thermal coupled energy levels 2H11/2 and 4S3/2 of Er3+ ions was evaluated in the visible light region. The absolutely sensitivity of SrGdAlO4: Er3+, Yb3+ and SrGdAlO4: Er3+, Yb3+, Bi3+ are 3.8 × 10−3 K−1 and 6.1 × 10−3 K−1 respectively. The results indicated that codoping Bi3+ ions can improve the luminescent intensity of SrGdAlO4: Er3+, Yb3+, but also strengthen its temperature sensing characteristics.

The goal of this study was to identify the relative contribution of fossil and non-fossil contributions to PM2.5 carbonaceous aerosols (CAs) in PM2.5 pollution events. To achieve this, the pollution characteristics and source apportionments of CAs using radiocarbon (14C) and organic tracers (anhydrosugar) were determined during a long-lasting winter haze episode (Jan. 13–24, 2018) in Xiangyang, central China. Non-fossil sources (biofuel, biomass burning, and biogenic emissions) contributed 74 ± 3% and 35 ± 2% to organic carbon (OC, 20.7 ± 6.79 μg/m3) and elemental carbon (EC, 6.48 ± 1.79 μg/m3), respectively. During the winter haze episode, CAs were derived from primary biofuel and biomass burning-derived OC (POCbb, 27.3 ± 4%), secondary biofuel and biomass burning-derived OC (SOCbb, 26.7 ± 5%), fossil sources-derived EC (ECf, 15.4 ± 3%), secondary fossil sources-derived OC (SOCf, 14.7 ± 1%), biofuel and biomass burning-derived EC (ECbb, 8.4 ± 2%), primary fossil sources-derived OC (POCf, 5.5 ± 1%), and secondary biogenic sources-derived OC (SOCbio, 2.0 ± 1%). Biofuel and biomass burning contributed more to PM2.5 pollution compared to traffic exhaust, which indicated that the public and government should pay attention to control biofuel and biomass burning in Xiangyang, central China.

Single-phase silicon oxynitride (Si2N2O) was prepared in a N2 atmosphere by combustion synthesis with Si and SiO2 as the reactants. The effects of process parameters, including N2 pressure, Si2N2O diluent and NH4Cl content, on the combustion temperature, as well as phase composition and microstructure of products were investigated. The high-temperature wetting behavior of Si melt on the as-prepared Si2N2O coating was then tested by the sessile drop method. It was found that Si melt shows poor wettability to Si2N2O coating at 1500 °C with the steady contact angle of 120°, indicating that the combustion-synthesized Si2N2O powders could be used as a potential novel releasing agent material for photovoltaic silicon casting application.

Alpha phase silicon nitride (α-Si3N4) powders were synthesized by combustion reaction of the in-situ nano-SiO2 coated Si and Si3N4 reactants with pressurized nitrogen. The combustion temperature profile as well as the product phase composition and morphology were investigated. Regardless of the combustion temperature reached as high as 1800 °C, up to 86 wt% α-Si3N4 was obtained in the combustion-synthesized product from the reactants with only 6 wt% SiO2 addition, which is three times higher than that of without SiO2 coating, meanwhile, the morphology of Si3N4 grains changed from rod-like to equiaxed grain，indicating the in-situ coated SiO2 tailored the nitridation reaction path of Si successfully by enhancing the silicon monoxide (SiO) gas phase formation.

A novel combinatorial synthesis method based on electric field-assisted combustion synthesis was developed to fabricate multiple ZrxTi1-xC solid solutions using Zr, Ti, and C elemental powders. The microstructure, phase composition, and near-infrared emission property of the prepared ZrxTi1-xC solid solutions with different Zr/Ti mole ratios were investigated. The prepared ZrxTi1-xC solid solutions all formed a single cubic structure. It was found that, the grain size of ZrxTi1-xC solid solution decreased as the ratio of Zr and Ti atoms approaches equal proportions. The emissivity of the ZrxTi1-xC solid solutions was 0.55-0.89 in the 0.25-2.5 μm wavelength range and exhibited an average emissivity over 0.80 for x = 0.7500, 0.5000, 0.1875, respectively.

Graphite flake/Cu composite has attracted tremendous attention as a promising heat sinks materials owing to its easy machinability and superior thermal properties. However, its preparation process still faces several technological limitations including complex, time-consuming and costly synthetic approaches. In this work, a facile and scalable intermittently electroplated method is applied to prepare Cu-coated graphite flake composite powders, which are subsequently sintered into dense composite bulks. The results show that the graphite flake is successfully coated with a uniform and compact Cu shell, which effectively inhibits the segregation accumulation of graphite flakes and contributes to homogeneous distribution of graphite in the sintered graphite flake/Cu composites. The as-sintered composites exhibit an excellent thermal conductivity of 710 W·m−1·K−1 and an outstanding bending strength of 93 MPa. Such performance, together with the simple, efficient powder-preparation process, suggests that the present strategy may open up opportunities for the development of thermal management materials.

At present, the ultra-fine particulate matter (UPM) with diameter less than 1 μm cannot be filtered efficiently and precisely by the current filtration materials, which leads to the UPM being the main source of air pollution. Here, we prepared Kaolin/silica/mullite fiber multilayer membranes (KSFMs) by a simple vacuum filtration. The UPM filtration efficiency has been significantly improved by the nanoporous kaolin layer coated on the support body constructed by Si-sol bonded mullite fiber. By controlling the size and amount of kaolin particles in the mixed suspension, the structure and filtration efficiency and filtration resistance of the multilayer membranes are optimized. The multilayer membranes exhibit high UPM filtration efficiency with 99% for 0.3 μm and low filtration resistance (lower than 70 Pa at 0.3 m/s).

We investigate the testable implications of the theory of stable matchings in two-sided matching markets with one-sided preferences. Our main result connects the revealed preference analysis to the well-known lattice structure of the set of stable matchings, and tests the rationalizability of a data set by analyzing the joins and meets of matchings.