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Ordered lamellar superstructured zirconia (OLSZ) was successfully synthesized via a reflux-hydrothermal method. ZrOCl2, NaOH and methanol were used as zirconium source, precipitant and template, respectively. Methanol induced and directed the hierarchical structures: 0.57-nm thick ultrathin crystal framework, 1.14-nm periodic lamellar superstructure, several nanometers thick petal-like multilayered nanosheets, and flowers-like higher-level structure. OLSZ presented outstanding hierarchical thermostabilities up to 800 °C. The synthetic mechanism was proposed based on Gibbs theory and calculations. Compared with surfactant method, methanol template route presents many advantages, such as green, facile, efficient and low-cost, moreover the template is very easy to remove. This novel small molecule template strategy will be of great significance for the synthesis of other superstructured materials.

A green manufacturing technology named “electrostatic minimum quantity lubrication (EMQL)” with water-based Al2O3 nanoparticle fluids as cutting fluids was developed in order to improve the cutting property and minimize oil mist concentration during the machining process. The capillary penetration mechanism, oil mist concentration, and heat transfer property of Al2O3 fluid EMQL were investigated. The cutting performance of Al2O3 fluid EMQL and traditional minimum quantity lubrication (MQL) was compared. The results showed that EMQL could improve the penetrability and heat transfer capacity of the lubricant effectively. Compared with Al2O3 fluid MQL and oil-based MQL, Al2O3 fluid EMQL reduced oil mist concentration and cutting temperature remarkably and showed similar cutting performances compared with the oil-based MQL. The excellent performance of this water-based Al2O3 fluid EMQL technology was mainly due to that EMQL could promote a further penetration of the charged Al2O3 nanofluid droplets into the cutting region, which thus reduced the friction force, and the tool durability was maintained obviously and finally presented better machining performance.

Both thermodynamic performance and techno-economic analysis of compound power cycles for enhanced geothermal systems have been investigated in this study. Thermodynamic analysis were carried out for four power generation systems: single-flash (SF) system, double-flash (DF) system, flash-ORC (FORC) system; and double-flash-ORC (DFORC) system. By choosing the maximum net power output as an objective function, optimization is done based on comparisons among the four systems with a goal of increasing the net power output by 20% under the condition that the SF is replaced by one of the compound systems (DF, FORC, and DFORC). As an original contribution, five maps useful for real applications have been generated for selecting optimum geothermal power cycles under different geofluid’s conditions, with consideration of five ORC working fluids (R123, R152a, isobutane, n-pentane and R245fa). The boundaries that determine whether the compound systems have advantages over the SF system are functions of the geofluid temperature, geofluid dryness, and the type of the working fluid used by the ORC. In the techno-economic study, Levelized Electricity Cost (LEC) and Payback Period (PBP) analyses were carried out. The results from the LEC and PBP studies show good agreement. For the three scenarios analyzed, each of the compound power systems has a better engineering economic performance than the SF system. For the “common” heat source condition investigated, comparison among the three compound systems shows that the DF system has a lowest levelized electricity cost and the shortest payback period; the FORC and DFORC show similar techno-economic performance and have advantages over the SF system.

Earthquakes can cause serious damage to traffic infrastructures, among which the impact on bridge structure is the most important. Therefore, in order to assess bridges serviceability, it is important to master their damage mechanism and to analyze its probability of occurrence under a given seismic action. Various uncertainties, like the location of epicentre of future earthquakes and their magnitudes, make this task quite challenging. We are also required to consider different earthquake scenarios and the damaged states of bridge components associated with those earthquakes. To suppress these difficulties, this study proposed a new method of performance-based seismic fragility and risk assessment for bridges. The proposed method included three steps: (1) performance-based seismic fragility estimation of a five-span continuous rigid frame bridge, (2) seismic hazard analysis for locations of the bridge, and (3) seismic risk analysis of the bridge. The proposed method that considered the performance of the bridge and the uncertainty in the location of the earthquake epicentre and magnitudes can provide valuable references for seismic-resistant design of multispan continuous rigid frame bridges in the future.

Solar enhanced natural draft dry cooling tower(SENDDCT) is a new heat rejection device that uses solar energy to increase the cooling efficiency of natural draft dry cooling tower. In this paper, an experiment study was carried out t under natural conditions to investigate the effect of solar radiation intensity on the performance of SENDDCT. Meanwhile, a same-size CFD model was developed by using FLUENT to analyze the influence of ambient temperature on the cooling performance of SENDDCT. The results verified that SENNDCT can enhance heat transfer rate of natural draft dry cooling tower when ambient temperature was high at noon, solar radiation increased heat transfer rate by an average of 16.5% during the experiment. Air mass flow and heat transfer rate decreased with the increase of ambient temperature.

In this study, the optimum flash and evaporation temperatures have been selected for the following four geothermal power generation systems: single-flash system (SF), double-flash system (DF), flash-organic Rankine cycle system (FORC), and double-flash-organic Rankine cycle system (DFORC). Optimization is based on the maximum net power output of each system, with the pump and fan consumptions being taken into account. Under the given geofluid’s condition (temperature= 170oC; dryness= 0.2), the optimum flash temperature of SF, the optimum 2nd-stage flash temperature of DF, the optimum evaporation temperatures of FORC and DFORC are found to be 150oC, 100oC, 100oC, and 70oC, respectively. More scenarios have been analyzed for geofluid’s temperatures ranging from 80oC-260oC and geofluid’s dryness values of 0, 0.2, and 0.4 respectively. The result shows that the optimum 2nd-stage flash temperature of DF is close to the optimum evaporation temperature of FORC under the same geofluid’s condition, especially when the geofluid’s temperature is below 170oC and the dryness is below 0.2.

A novel surface patterning nanorod (hydroxyapatite nano labyrinth, HANL), covered with labyrinthine nanogrooves on surface, was successfully synthesized with the assistance of tetrahydrofuran (THF). THF as the sole organic molecule not only promoted HA crystal growth, but also induced and stabilized the hierarchical nanorod. XRD results indicated that HANLs were of high phase purity and were well crystallized. SEM and TEM images showed that HANLs were of the length of 75–425 nm and the width of 20–85 nm, and were of 1-9-nm wide grooves covering over the surface which were also confirmed by the N2 adsorption analysis. The synthetic mechanism was proposed and explained in thermodynamics combined with theoretic calculations. This novel hierarchical HANLs may have great potential applications in bone replacement materials, composites, adsorbents, carriers, etc. This THF assisted synthetic strategy is green, low-cost, efficiently and surfactant-free, and may be useful in surface patterning other functional materials.