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With the acceleration of the construction of sponge cities in China, porous asphalt pavement (PA) is has been widely used. High-viscosity asphalt (HVA) is the core material in building PA because it has good rheology properties, which can provide good raveling and rutting resistance. However, due to the open-graded structure of PA, HVA was more susceptible to rapid aging, which significantly affects the durability of PA. To investigate the thermal aging effect on the rheological properties of self-modified HVA (SHVA), five types of asphalts were aged using a rolling thin film oven (RTFO) and pressure aging vessel (PAV). Then, rheological tests were adopted, such as temperature sweep test (TS), repeated creep and recovery test (RCR), and bending beam rheometer test (BBR). The results indicate that during the aging process, the oxidation-induced hardening effect of neat asphalt and the degradation-induced softening effect of the modifier changes the rheology properties of HVA significantly. As the aging progresses, the contribution of the modifiers of HVA to anti-aging performance is greatly reduced. At high temperatures, HVA demonstrates better anti-aging performance than conventional styrene–butadiene–styrene (SBS)-modified asphalt (Guo Chuang, GC). The change of the high-temperature rheological indices of the two HVA types (SHVA and TAFPACK-super HVA (TPS)) showed a smaller activation energy index (EAI), a more considerable viscous component of binder creep stiffness (Gv), and more minor accumulated stain (racc), indicating a more significant anti-short-term and long-term aging performance, which is beneficial to the high-temperature performance of asphalts. However, the changes in low-temperature rheological properties do not align with those in high-temperature rheological properties after long-term aging. The BBR test results reveal that TPS exhibits worse low-temperature performance than GC and SHVA. During the thermal aging process, the contribution rate of the modifiers in SHVA against RTFO and PAV aging is higher than that of the modifiers in TPS, which contributes to the superior anti-aging property. Overall, SHVA demonstrates the best anti-aging performance among the five asphalts tested. [ABSTRACT FROM AUTHOR]

Temperature maintenance is one of the leading factors for the large-scale energy consumption in buildings, which accounts for 33% of the total consumption. The heavy smog in China resulting from the depletion of fossil fuels necessitates the development of new technologies that can reduce the energy usage in buildings. Several techniques for building's thermal insulation were developed among which the utilization of Vacuum Insulation Panels (VIPs) has the leading edge. For refrigeration purpose in VIPs, the glass wool is being used as a core material because of their low thermal conductivity (λ ≤ 2 mW/m·K) and low cost. However, the silica-fly ash has been preferred as a core material of VIPs for buildings because of its high compressive strength (σc > 2 MPa) and the most economical price. Moreover, the P 1/2 of the glass wool VIP and silica-fly ash VIP are 10–100 and 1000 Pa, respectively. In this work, the performance of VIPs with various cores has been compared. The thermal conductivity of VIPs, along with the factors affecting thermal conductivity, such as density, thickness, internal pressure, and porous structures, have been evaluated. In addition, the effect of core materials on the cost of VIPs was also quantified. It is expected that the study will serve as a pioneering work in the foundation to development of the next-generation, low-cost VIPs used for building insulations. [ABSTRACT FROM AUTHOR]

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• A conceptual design of FuSTAR is developed, and validated by neutronics and thermal-hydraulics analysis. • Detailed core design and neutronics analysis with near-critical configuration and burnup calculation are carried out. • Detailed thermal-hydraulics analysis with turbulent flow and heat transfer is carried out. The fluoride-salt-cooled high-temperature advanced reactor (FuSTAR) is an advanced small modular reactor, which aims to the electric supplement and clean heat production to western China. In order to have good economy and safety, FuSTAR needs to have the characteristics of small size, light weight, deep burnup, and inherent safety. A conceptual design of FuSTAR is proposed in this study with neutronics and thermal-hydraulics assessments. In this study, its concept is established with two-region fuel to flatten core power, and the neutron spectrum of the core is in the thermal spectrum to improve the utilization of thermal neutrons and reduce fuel inventory. Neutronics and thermal-hydraulics analyses are also carried out, and established the core layout and material ratio under the near-critical condition. Burnup depth of the fuel, power distribution, neutron flux distribution, flow and heat transfer in rod-bundles channel, and 1/6 core porous media analysis are also investigated. The parameters of the designed core are evaluated quantitatively from various aspects. The results show that the core design in this study has sufficient shutdown depth, the equilibrium cycle is 3.24 years, and the discharge burnup depth is 106 GWd/MtU. The helical cruciform fuel (HCF) adopted by this reactor has a better flow and heat transfer capacity than cylindrical-type fuel at the inner channel. The analysis of 1/6 core porous media shows that the peak fuel temperature under normal operating condition is 1009.3 K, which is far below the limit of 1573 K. Relevant design and analysis results can provide the reference for the subsequent small modular FHR design and construction. [ABSTRACT FROM AUTHOR]

As an industrial waste material, the utilization rate of wood processing residues in China is only 30%, and the high-efficiency utilization of wood processing residues can greatly alleviate the shortage of wood resources in China. This study suggested a novel treatment method for conserving wood resources by recycling wood processing residues as core materials for wooden doors, the feasibility of which was validated through an actual production operation in a wooden door manufacturing factory. Since the recycling process requires a series of processes, two comparison scenarios were proposed in this study in order to assess whether the recycling method can reduce the environmental impact and thus generate environmental benefits. Scenario 1 conducted a comparative LCA analysis among wood processing residues and two commonly used core materials for wooden doors, namely, tubular particleboard and laminated veneer lumber (LVL). Scenario 2 conducted a comparative LCA analysis between two treatment methods for wood processing residues, namely, recycling as core material and incineration as boiler fuel for heat production. The results revealed that using wood processing residues as a core material for wooden doors reduced the emission of approximately 7.46 kg CO2 eq of GWP and 143.77 MJ of PED when compared to tubular particleboard, but when compared to LVL, recycling of wood processing residues produced no environmental benefits but exerted a negative impact. In addition, recycling wood processing residues to replace tubular particleboard as core material for wooden doors is a superior method of disposal compared to incineration as boiler fuel for heat production. [Display omitted] • This study suggests a novel treatment method for wood processing residues. • The system boundary expansion with substitution (SBES) approach was applied. • Comparative LCA was conducted among different wood processing residue treatment methods. • Recycling wood processing residues to replace tubular particleboard is an ecological disposal method. [ABSTRACT FROM AUTHOR]

The middle interval of the 3rd member of the Shahejie Formation (Es 3 m) of the Dongying Depression accumulated as part of a system of converging deltas derived from multiple source regions. These complex deposits that are targets of oil/gas exploration and development in eastern China have yet to be studied at the level of detail necessary to elucidate their origin and sedimentary evolution. This paper relies upon a multi-faceted investigation of the Es 3 m depositional system that includes analysis of clastic compositions, heavy mineral assemblages and mineral ratios, and clay mineralogy to illuminate the provenance of Es 3 m deposits. Compositional data is obtained by analysis of logs and core material. Our results reveal that Es 3 m deposits were derived from source regions to northeast (Qingtuozi Uplift and Chenjiazhuang Uplift) and southeast (Weibei Uplift and Guangrao Uplift) of the Dongying Depression. Each source region shed sediment to the study area that accumulated in distributary channels, interdistributary swamps, natural levees, mouth bars, underwater distributary channels, sand sheets and underwater distributary interchannel regions. Moreover, lacustrine shore and semi-deep lacustrine deposits that include turbidites are recognized in the studied succession. The separate deltas appear to have converged approximately halfway through the depositional history of the Es 3 m Formation. Convergence continued in association with delta progradation, forming overlapping sand bodies that are targets of hydrocarbon exploration. [Display omitted] • A multi-faceted approach to determine provenance of two converging deltas. • Two deltas came from isolated highs converged in an Eocene lacustrine rift basin. • Different methods lead to similar results in provenance analysis. • Provenance analysis is an effective method to predict sand body distribution. [ABSTRACT FROM AUTHOR]

Recently, the structural insulated panels (SIPs) with the wood-based surfacing materials are developed in housing industry to increase the thermal efficiency of the wall system. In order to integrate the waterproof feature into SIPs, a newly designed GFRP reinforced squared tube sandwich panel (GSTPs) is introduced, where the Glass fibre reinforced polymers (GFRP) is utilized as surface material and the core is reinforced by the GFRP square tube. This paper focused on the thermal insulation performance of GSTPs. Both experimental, theoretical and numerical methods are employed to study their thermal insulation performance as roof panels. More specifically, the thermal conductivity of GFPR with three different core materials, including glass wool, Extruded polystyrene (XPS) and Polyurethane (PU) in the SIP, was first measured by hot plate apparatus (HPA) in the steady-state heat transfer tests. Then, the heat transfer coefficients of three type of GSTPs with above mentioned core materials are measured by guarding heat box (GHB) test. The theoretical and finite element (FE) method based numerical studies applied to conduct the heat transfer analyses on those SIPs. The accuracies of the theoretical and numerical studies are verified by comparing the obtained heat transfer coefficients with those from the experimental tests. The results from the present study could provide a good reference to the selection of the suitable panel thickness and core materials for different thermal regions in China. [ABSTRACT FROM AUTHOR]