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High-voltage cathodes paired with lithium metal anode have aroused extensive interests owing to their application potentials for high-density energy storage. Nevertheless, conventional electrolytes fail to maintain the stability of high-voltage cathodes and Li anode, due to their rigid interfacial chemistry with low adsorption of transition metal and strong bonding with Li+ ions. These inadequate interactions exacerbate issues such as transition metal dissolution and non-uniform Li+ transference, ultimately resulting in low cyclability of high-voltage lithium metal batteries (HVLMBs). By incorporating fluoroethylene carbonate (FEC) into lithium bis(trifluoromethane sulfonyl) imide (LiTFSI)/tetramethylene sulfone (TMS) solution, we design a sulfone-based electrolyte to improve the cyclability of HVLMBs with bi-electrode affinity characteristic—the TMS solvent with outstanding anti-oxidation stability preferentially tends to the aggressive cathodes while the FEC solvent with excellent film-forming ability approaches to the Li anode, attributed to the different adsorption energy between various solvents and electrodes. In addition, the sulfone electrolyte forms ultra-thin fluorine and sulfur-rich interphases, containing LiSO2F with S=O bonds of low electron density, associated with Li+ and e− species attacking the S-C and S-N bonds of LiTFSI and the S-C bonds of TMS. As confirmed by in-situ Raman, Ab initio molecular dynamics, and phase field simulations, the LiSO2F uniformizes in-plane Li+ transfer and mitigates transition metal dissolution, owing to the smallest Li+-LiSO2F bonding value (-1.95 eV) and the largest transition metal absorption value with LiSO2F (-3.86 eV) ever reported in the interfacial components. With Coulombic efficiency of 99.3%, the electrolyte enables an 86.1% retention after 500 cycles for Li/NMC811 (4.40 V) batteries.

Upconversion spectral converters enable the utilization of infrared photons for dye-sensitized solar cells. However, the TiO2 photoanode photoelectron trapping loss caused by defects and ligands on upconversion material surface limits the dye-sensitized solar cells efficiency. Here, we separate spatially TiO2 particles and upconverters through crafting an uniform semiconductor BiOCl shell onto NaYF4:Yb3+,Er3+ upconverters surface by a hydrothermal method. Unlike common insulate SiO2 shells, the BiOCl shell decreases little the upconversion luminescence intensity from the upconversion core, but it can inhibit the photoelectron transfer from TiO2 to upconversion particles due to its higher conduction band position than that of TiO2, which eliminates the photoelectron trapping loss. In addition, the BiOCl shell can harvest 408 nm photons from upconversion cores to generate additional photoelectrons into TiO2 photoanode film. Consequently, the incorporation of upconversion-core/semiconductor-shell structured particles into TiO2 photoanodes of dye-sensitized solar cells achieves 29.8% increase of power conversion efficiency, whereas bare upconversion particles only get 11.9% increase as compared with dye-sensitized solar cells with pure TiO2 photoanodes. We quantify that among the relative efficiency increase by the incorporation of upconversion-core/semiconductor-shell particles: 17.2% from the reduced photoelectron trapping and the harvest of upconversion 408 nm photons by BiOCl shell, 4.9% from the green and red upconversion of near infrared photons, and 7.7% from the scattering effect of the designed spectral upconverters.

Two-dimensional (2D) metal oxides and chalcogenides (MOs & MCs) have been regarded as a new class of promising electro- and photocatalysts for many important chemical reactions such as hydrogen evolution reaction, CO2 reduction reaction and N2 reduction reaction in virtue of their outstanding physicochemical properties. However, pristine 2D MOs & MCs generally show the relatively poor catalytic performances due to the low electrical conductivity, few active sites and fast charge recombination. Therefore, considerable efforts have been devoted to engineering 2D MOs & MCs by rational structural design and chemical modification to further improve the catalytic activities. Herein, we comprehensively review the recent advances for engineering technologies of 2D MOs & MCs, which are mainly focused on the intercalation, doping, defects creation, facet design and compositing with functional materials. Meanwhile, the relationship between morphological, physicochemical, electronic, and optical properties of 2D MOs & MCs and their electro- and photocatalytic performances is also systematically discussed. Finally, we further give the prospect and challenge of the field and possible future research directions, aiming to inspire more research for achieving high-performance 2D MOs & MCs catalysts in energy storage and conversion fields.

During co-pyrolysis, active alkali and alkaline earth metals (AAEMs) can influence the synergistic effect of coal and biomass. For exploring the influence of active AAEMs on the co-pyrolysis process, this paper studied the physicochemical properties and gasification reactivity of co-pyrolysis char of four blends: raw coal and raw corn stalks (RC&RCS), pickling coal and raw corn stalks (HC&RCS), raw coal and pickling corn stalks (RC&HCS), and pickling coal and pickling corn stalks (HC&HCS). The results show that the synergistic effects on char yields are within 3%. During co-pyrolysis, the presence of corn stalks is beneficial to the generation of spherical particles from coal char, and the promotion effect of pickling corn stalks is greater than that of the raw corn stalks. The active AAEMs have an inhibitory effect on the decomposition of aliphatic C–H, C O and –CH3 in Shenmu coal, and also on the decomposition of O–H, aliphatic C–H and C–O in the corn stalks. The experimental values of gasification residual carbon of RC&RCS/HC&RCS co-pyrolysis char are 24–77% of the calculated values, while that of RC&HCS/HC&HCS co-pyrolysis char are 86–103% of the calculated values. The interaction between the blends promotes the reactivity of co-pyrolysis char.

In this study, a novel analytical method for predicting bending and springback behaviours of hexagonal close-packed (HCP) sheet metals is presented. The proposed analytical approach is developed by using the Cazacu-Barlat 2004 asymmetric yield function and isotropic plastic hardening rule. This model can be used to determine bending moment-curvature relationships and springback of HCP metals under uniaxial and plane strain loading conditions. Furthermore, to capture the nonlinearity in unloading and to improve springback prediction, the variable elastic modulus approach is implemented in the proposed model. The proposed new model reveals that reverse effects of the back force on springback behaviours cannot be found under the plane strain condition, which could not be found by using any existing models. Moreover, the analytical model is implemented into Abaqus via UMAT subroutine for its application in complex cases, and a numerical model is then developed as a showcase. The proposed methods are validated by using those experimental results available in literature. The results show considerable improvements by considering the plane strain condition and nonlinear unloading.

Simultaneous realization of upconversion (UC) and downconversion (DC) processes in a single unit provides unique opportunities of photons utilization throughout a broad spectral range for dye-sensitized solar cells (DSSCs). Yet, the existence of cross relaxation quenching effect in UC/DC interface causes a low synergistic effect. Here, we propose a strategy of embedding an inert layer to spatially separate active UC and DC layers at precisely defined thickness. The construction of sandwich-nanostructured NaYF4:20%Yb3+,2%Er3+@NaLuF4@NaYF4:15%Eu3+ allows the elimination of detrimental cross relaxation quenching, implementing optimal synergistic effect of UC/DC system and further extending simultaneous near-infrared (NIR) and ultraviolet (UV) absorption of DSSC devices to the most extend. By incorporating the sandwiched UC-core/inert-shell/DC-shell nanoparticles into the TiO2 photoanode of DSSCs, the increased photon-electron conversion efficiency (PCE) of 7.87% was obtained mainly by the increased photocurrent of 14.93 mA/cm2 due to the concurrent NIR and UV light harvesting enhancement (PCE = 6.73%, Jsc = 11.91 mA/cm2 for the control cell without the sandwiched spectral layer), thus, showing a noticeable PCE enhancement ratio of ∼16.94%. This work provides a promising strategy to integrate various photons processes in one single unit and broaden spectral respond toward high-efficiency solar cell systems.

In this study, the Co(OH)2-Co3O4/graphene (g-composite), Co(OH)2-Co3O4/MWCNT (n-composite), and Co(OH)2-Co3O4/carbon black (b-composite) composite were synthesized via facile solvothermal methods. The crystalline structure, morphology and chemical composition of these nanocomposites were characterized with XRD, SEM, and TEM in details. The XRD, XPS, and Raman results delivered comprehensive structural evidence for the Co(OH)2-Co3O4/carbon composites. The SEM and TEM results corroborated on the flower-like morphologies of the nanocomposites from different reaction temperatures and reagents ratios. Moreover, the Co(OH)2-Co3O4 spheres of hierarchically porous structure uniformly distributed on the carbon substrates. The ultra-lightweight composites featured the highly facile synthesis and superior performance. The minimum reflection loss of Co(OH)2-Co3O4/graphene nanocomposite reached −55.8 dB at 10.56 GHz with a coating of only 2.03 mm, and presented a relatively broad absorption bandwidth (RL ≤ −10 dB) in 8.4–12 GHz.

Sediment phosphorus (P) release and retention are important in controlling whole-system P dynamics and budget in eutrophic lakes. Here we combine short- (seasonal) and long-term (years to decades) studies to quantify the internal P loading and P release potential in the sediments of Lake Chaohu and explore their controlling mechanisms. In the west region of the lake, short-term P diffusive fluxes ranged from 0.2 mg/m2·d-1 to 6.69 mg/m2·d-1 (averaged 2.76 mg/m2·d-1) and long-term net P release ranged from 2.25 mg/m2·d-1 to 8.94 mg/m2·d-1 (averaged 5.34 mg/m2·d-1); in the east region, short-term P diffusive fluxes varied from 0.73 mg/m2·d-1 to 1.76 mg/m2·d-1 (averaged 1.05 mg/m2·d-1) and long-term P release ranged from 0.13 mg/m2·d-1 to 4.15 mg/m2·d-1 (averaged 1.3 mg/m2·d-1). Both short- and long-term P releases were in the same order of magnitudes as the external P inputs (3.56 mg/m2·d-1). Comparison of the long-term and short-term sediment P release indicates that while the high summer P release in the east might only represent a snapshot value, the sediments in the west contribute to large P release for years or even decades, impeding water quality recovery under lake management. Mobilization of surface sediment legacy P accounted for 81% of short-term P release. The long-term release was dominated by remobilization of iron bond P (BD-P) (average 52.1%) at all sites, while Aluminium-bound P (NaOH-rP) exhibited partly reactive and potentially mobile, releasing P to the water column in most sites in the west. Our study demonstrates the importance of sediments as P sources in lake Chaohu. The combination of short- and long-term P release studies can help understand the roles of sediments in regulating the water quality and eutrophication.

This paper presented a comparative study on plasticity and fracture behaviour of nanostructured Ti/Al multilayers with two individual layer thicknesses λ. The nanoindentation results showed that film buckling appears in the 10 nm multilayer, whereas localised shear bands are detected in the 100 nm multilayer. The nanoscratch results indicated that localised conformal cracks and spalling are the dominant fracture mode in the multilayer with λ = 10 nm, whereas adhesive failure is observed in the 100 nm multilayer when a critical normal load is reached. The work of adhesion of the 10 nm multilayer was much larger than that with λ = 10 nm, possibly due to the high hardness and few dislocation slips by the confined layer mechanism.

Nitrogen (N) and phosphorus (P) pollution from aquaculture has increased dramatically in recent years, and it is urgent to develop a cost-effective method to clean these polluted waters. The objective of this study is to investigate N and P removal using a two-stage infiltration system based on NaCl modified clinoptilolite (NCLP) and thermally-treated calcium-rich attapulgite (TCAP). Results from a batch study indicated that the maximum ammonium sorption capacity of NCLPs was in the range of 6.64 to 7.27 mg. N/g and decreased slightly among the three particle sizes studied (0.2–0.5 mm, 0.5 mm–1.0 mm and 1–2 mm). A 150-day column experiment indicated that the two-stage infiltration system achieved an average removal efficiency of 99.4% N and 99.0% P, and a removal rate of 50.3 g N/m3/d and 8.83 g P/m3/d for an influent concentration of 50 mg N/L and 10 mg P/L with a hydraulic retention time (HRT) of 16 h. When the influent concentration increased to 100 mg N/L and 20 mg P/L, the average ammonium removal efficiency decreased to 65.3%, while the system can still keep a high average P removal efficiency of 97.9% for 72 days of the experiment. Longer HRT favored N and P removal efficiency, but short HRTs can oxygenate ammonium sorbed in the NCLP filter and thereby refresh its sorption capacity. The results also indicated that longer wet and dry cycles can enhance the N removal efficiency of the system, but had minor influence on P removal. The sorbed clays contained high N and P content and might have use as a slow-release fertilizer. The results of this study indicate that a reactive clay-based treatment system can be used for dual removal of N and P from aquaculture wastewaters, making possible the development of a sustainable aquaculture model.

A facile route toward monolithic porous SiOC ceramics from preceramic polyphenylsilsesquioxane (PSQ) aerogels was reported herein. The supercritical drying derived aerogels were synthesized through a sol-gel process wherein Span-20 was used to suppress the phase separation that caused by the oligomers of hydrolysed precursors. It was found that the amount of Span-20 had a significant effect on the microstructure of PSQ aerogels. At an optimized condition, as-synthesized aerogel showed a narrow pore size distribution (~12 nm) and a high specific surface area (632.27 m2/g). Moreover, the structure evolution as well as the phase transformation of the aerogel at different sintering temperatures were simultaneously investigated. Porous amorphous SiOC monoliths with specific surface areas up to 247.06 m2/g were synthesized under 1200 ℃. While for aerogels pyrolyzed over 1400 ℃, the microstructure collapsed and only bulk SiC ceramics were obtained.

Extending the spectral absorption of dye-sensitized solar cells from the visible into near-infrared and ultra-violet range enables the minimization of non-absorption loss of solar photons. Here, we report a viable strategy to implement simultaneously near-infrared upconversion and ultra-violet downconversion for dye-sensitized solar cells through constructing a type of upconversion-core/downconversion-shell-structured nanoparticles. For the first time, NaYF4:20%Yb,2%Er@NaYF4:7%Eu core/shell nanoparticles are applied to TiO2 photoanode for fabricating near-infrared/ultra-violet-enabled dye-sensitized solar cell devices. The incorporation of designed nanoparticles into TiO2 photoanode of dye-sensitized solar cells achieves high efficiency of 7.664% under one sun illumination, increasing the power conversion efficiency by about 13.95%. We confirm that the enhancement of overall efficiency includes 4.82% upconversion contribution, 7.58% downconversion function and 1.55% scattering effect. Our strategy opens the path for further broadening the solar spectral use to improve the performance of photovoltaic devices.

In this study, a multiscale simulation analysis combining mesoscale dissipative particle dynamics (DPD) method and continuum mechanics based finite element method (FEM) is adopted to study the morphological and mechanical properties of graphene-reinforced poly(methyl methacrylate) (PMMA) nanocomposites. Specifically, DPD simulations are performed for PMMA nanocomposite systems with graphene of different surface chemistries (i.e., GN, FGN and PMMA@FGN) and different process routines. It is found that the covalently functionalised PMMA@FGN/PMMA system can achieve a better dispersion than that of untreated GN/PMMA system, which is attributed to the intercalated coating molecules between graphene nanofillers. However, increasing shear rate during processing may not result in a better nanofiller dispersion or orientation as expected. The DPD microstructures of nanocomposite systems are subsequently mapped onto a 3D finite element representative volume element (RVE). The mechanical properties obtained from FEM match reasonably well with those from experiments in literature, which further demonstrated the effectiveness of the proposed multiscale approach.

This study presented length-scale-dependent room temperature creep behaviour of Ti/Al multilayers by nanoindentation. Ti/Al multilayers with individual layer thickness ranging from 10 nm to 250 nm were prepared by a direct current magnetron sputtering method. Microstructural analysis showed that the prepared Ti/Al multilayers were polycrystalline, with strong Ti (0002) and Al (111) texture. Nanoindentation creep tests were performed to examine the time-dependent creep deformation, stress exponent, creep strain rate sensitivity and contact creep compliance of the multilayers at room temperature. It was found that both the maximum creep deformation and the creep strain rate sensitivity increase with an increase in the individual layer thickness, indicating a length-scale-dependent creep behaviour of the Ti/Al multilayers. The values of stress exponent were found to lay in the range of 15.74–61.46, implying that the creep behaviour of the multilayers was controlled by the dislocation creep mechanism. Finally, the contact creep compliances of the Ti/Al multilayers were well modelled by a two-element Kelvin-Voigt model. From this, it was determined that the creep numbers and retardation times increased with increased individual layer thickness.

The solubility of carbendazim in the lower alcohols (Methanol, Ethanol, n-Propanol, n-Butanol, and n-Pentanol) at temperatures from 278.15 K to 323.15 K was measured by a dynamic thermodynamic equilibrium method. The solubility of carbendazim increased with the increasing temperature in each solvent. The experimental data were well correlated by Apelblat equation, and the dissolving enthalpy and entropy were calculated. The solution parameters demonstrated that the dissolution of carbendazim in each alcohol was an endothermic process of entropy increase. The change of standard Gibbs free energy illustrated that the dissolution process became more difficult when the carbon chain in the alcohols got longer.

Rare earth-contained compound Eu 5 In 2 Sb 6 which shows improved air stability and competitive thermoelectric properties in comparison to its alkaline earth analogues, has attracted much attention recently for thermoelectric applications. Polycrystalline samples Eu 5 In 2- x Cd x Sb 6 ( x = 0, 0.01, 0.02, 0.06, 0.08, 0.1) were synthesized via a direct element combination reaction and subsequent hot-press sintering. With increasing Cd concentration, both the electrical resistivity and Seebeck coefficient decrease monotonously, and the conductive behaviors vary essentially from non-degenerate semiconductor to degenerate semiconductor. The maximum value of power factor (5.78 μW/cm*K 2 ) can be obtained with x = 0.1. While the total thermal conductivity rise as a result of the contribution of electronic part, the thermoelectric figure of merit zT for Eu 5 In 2-x Cd x Sb 6 can be enhanced up to 0.5 at 709 K.

The decent flexibility and processability of solid-state polymer electrolytes (SPEs) endow them with broad development prospects in the solid-state lithium-based batteries field. Nevertheless, the poor room-temperature ionic conductivity of SPEs severely hinders their practical applications. Herein, we design a functionalized poly (vinylidene fluoride) (PVDF)-based electrolyte, and an ionic conductivity elevation is achieved by directly introducing zeolitic imidazolate framework-90 (ZIF-90) as filler into SPE. The metal ion sites of ZIF-90 can adsorb TFSI− with a large adsorption energy of −1.35 eV to facilitate the dissociation of LiTFSI. The SPE modified with ZIF-90 delivers the prominent ionic conductivity of 0.62 mS cm−1 at 30 °C and the low activation energy of 0.20 eV. Simultaneously, cells fabricated with LiFePO4 cathode exhibit the high specific discharge capacity of 118 mAh g−1 after 300 cycles at 1 C (0.44 mA cm−2) at room temperature. This work provides an efficient and promising strategy of fabricating competitive SPEs for solid-state lithium-based batteries.

The effect of mixing ratio and active alkali and alkaline earth metals (AAEMs) on gaseous products from co-pyrolysis of coal and corn stalks was investigated in this research. The thermogravimetric technique coupled with the Fourier transform Infrared spectroscopy (TG-FTIR) was used to investigate the mass loss of samples and the formation of typical products. The results indicated that the active AAEMs in coal and corn stalks are not conducive to the release of volatiles, and the effect of active AAEMs in corn stalks on the co-pyrolysis process is much greater than that in coal. In addition, the interactions between coal and corn stalks during co-pyrolysis are beneficial to the generation of C O group, and unfavorable to the generation of CH4 and light aromatic hydrocarbons. The active AAEMs in coal inhibit the generation of CO2 and C O group of coal, but promote the generation of aliphatic hydrocarbons, while the active AAEMs in corn stalks promote the generation of CO2 and C O group of corn stalks, but inhibit the generation of aliphatic hydrocarbons.

Struvite crystallization has attracted more and more attention as it is a promising strategy to recover phosphorus and nitrogen from wastewater and simultaneously produce a valuable fertilizer. However, the fine crystals formed during the process make the liquid–solid separation difficult which impedes its industrial application. This paper aims to produce struvite crystals with bigger sizes through the modification of crystal growth process. In this study, the metastable zone defined by pH was determined and pH of the solution was employed to modify the driving force of struvite crystallization process. With the aid of real time solution information, the continuous feed back control of pH-supersaturation was put forward and conducted to regulate the growth of struvite crystals. Secondary nucleation during the growth process was effectively inhibited which enhanced the final crystal size, and the settling velocity was improved about 10 times compared with those without growth regulation. The results showed that the crytallization technology with pH-supersaturation control might be a good solution to the problem of struvite separation.

As a key component of next-generation high-safety lithium batteries, solid-state electrolytes (SSE) have attracted extensive attention. Polyethylene oxide (PEO)-based solid polymer electrolytes exhibit outstanding flexibility and excellent electrode-electrolyte interfaces in comparison with that of inorganic solid electrolytes. Unfortunately, the practical applications of PEO-based solid polymer electrolytes are severely limited by the low ionic conductivity arising from the sluggish segment movement of PEO crystal phase. Herein, an SSE design is presented, which leverages the good flexibility of PEO and enhances its ionic conductivity by directly introducing hydroxyapatite (HAP) as filler into solid polymer electrolyte. With negative potential vacancies of surface, HAP filler can facilitate lithium salt dissociation with a minor dissociation energy of −0.76 eV by attracting Li +. A remarkable ionic conductivity of 0.064 mS cm−1 and a Li+ transference number of 0.366 at 30 °C are achieved. In addition, LiFePO4 (LFP)-Li cell with HAP-modified polymer SSE also delivers a capacity of 118 mAh g−1 after 500 cycles at 1 C at 30 °C, which confirms the practical operability of novel SSE and the validity of HAP filler for SSE enhancement.

The electronic, optical and lattice dynamics properties of GaSe1-xSx are investigated in detail using Density Functional Theory (DFT). The results indicate that the calculated dielectric and Raman spectra are in agreement with the experimental data. As the proportion of S-atoms increases, there is an increase in the band gaps and a decrease in the lattice parameters. Further, there are reductions in both the static electronic dielectric e1(0) and refractive index n(0), with the lattice vibrations of Ga-X (X = Se or S) bonds gradually strengthening and shifting towards the high-frequency region. These variation tendencies indicate a gradual increase in the interaction of Ga-X bonds with the increasing ratio of S-atoms. From the differential charge densities, the inter-layer and intra-layer interactions of GaSe0.75S0.25 are the weakest, with those of GaS being the strongest. Due to the highly anisotropic bonding forces, optical spectra of GaSe1-xSx present clear polarization anisotropy in the direction of vector E. The absorption and reflectivity spectra show that GaSe1-xSx are transmitted when frequencies are lower than 2.36 eV(525 nm).

The solubility of taurine in the binary water + acetone solvent mixture at temperatures from 278.15 K to 323.15 K was measured using the laser monitoring technique, and the experimental data were well correlated by the Jouyban–Acree model. The solubility decreased quickly when the mole fraction of acetone increased in the binary solvent mixture and also the metastable zone width got narrowed at the same time. Then the nucleation mechanism was investigated based on the induction time. The results showed that the homogeneous dominated at higher supersaturation while the heterogeneous nucleation dominated at lower supersaturation. Finally, a combined cooling and anti-solvent crystallization process was put forward. The product yield was raised to 96% from 73%, compared with the original cooling crystallization process in aqueous solution. What's more, the caking of taurine crystals was reduced and the fluidity of the product obtained was improved.

Fibre-reinforced cementitious composite (FRCC), by adding short discrete fibres randomly in cementitious composites, exhibits substantially improved mechanical properties than conventional cementitious composites due to the fibre bridging action and the existence of multiple micro-cracks. In this paper, based on the general self-consistent method a new micromechanical analytical model is developed to model the material properties of the FRCCs. A hexagonal-shaped representative volume element model with multiple micro-cracks is established based on the microstructure of the FRCC to represent the transversely isotropic material characteristics. The developed model is used to evaluate the equivalent Young’s modulus of a typical FRCC before and after cracking, and the results obtained are compared to those obtained from other analytical models and experimental data for validation. The influence of the aligned orientation of fibre and the crack density of the matrix on Young’s modulus of the composite is also studied.

Lightning strike damage in carbon fiber reinforced polymer (CFRP) composites with a lightning strike protection (LSP) system involves complex mechanisms. Few numerical studies simulating lightning strike damage have been developed considering the dielectric breakdown of LSP systems under lightning strike. This study presents a coupled thermal–electrical finite element (FE) model of the evolution of damage in CFRP composites with different advanced LSP systems under lightning strike. The advanced LSP system consists of a buckypaper layer and an adhesive layer. The dielectric breakdown strength of the adhesive layer and CFRP composite is incorporated into the FE model by an ABAQUS subordinate functionality. First, the FE model is utilized to predict damage to a CFRP composite without an LSP system. It is found that the predicted area and depth of damage agree well with the experimental data. Then, the lightning strike damage to CFRP composites with different LSP systems is quantitatively determined by the FE analysis. The results show that, after addressing dielectric breakdown, the FE predictions are comparable with experimental results for various LSP systems.

Emergency evacuation is an important task while dealing with a sudden accident. Aiming at emergency evacuation in campus, this paper proposed a personalized route planning model for pedestrian–vehicle mixed evacuation. Considering the congestion of pedestrian–vehicle mixed evacuation and the actual factors of students, this model found the optimal user equilibrium close to the system equilibrium. By the help of the Wardrop Equilibrium model, the server calculated the optimized evacuation route planning and guided evacuees by mobile intelligent terminals. Finally this paper applied this model to the evacuation of Wuhan University of Technology. By simulating the process of emergency evacuation, the results showed the feasibility of the algorithm, which proved this model a scientific basis for guiding the real evacuation process.

In this work, we report on a new approach to synthesize large-scale nonlinear optical chalcopyrite compound CdGeAs2 (cadmium germanium arsenide), in which the arsenic (As) precursor and the mixture of the cadmium (Cd) and the germanium (Ge) were separated in two distinct temperature-defined zones of a furnace. Through probing the intermediate product prepared at pre-set temperature points of hot-zone area, it was revealed that the ternary compound CdGeAs2 was formed through chemical reactions among Cd3As2, CdAs2, GeAs, GeAs2 and Ge. A new intermediate crystalline compound, with determined crystal parameter c=0.9139 nm and unknown a parameter, was identified when the temperature of the mixture of Cd and Ge was set to 680 °C, which, however, disappeared when the temperature was set to 770 °C, yielding pure CdGeAs2 product. Most likely, the identified new intermediate compound has layered graphite-like structure. Moreover, we show that the described two-temperature synthesis method allows us to produce near 250 g CdGeAs2 product during one run in a horizontal furnace and 500 g in a tilted horizontal furnace with rotated reactor.

Dredging and in situ adsorbent inactivation are two methods which are frequently used in eutrophic water bodies such as ponds, lakes and estuaries to control internal phosphorus (P) loading from sediments. However, their effects and modes on the control of sediment P loading has been seldom compared. In this study, a long-term sediment core incubation experiment in the field was undertaken to investigate changes in sediment P loading (P fluxes, supply ability and forms of P and transformation) comparing two remediation techniques, that of lanthanum-modified bentonite (LMB) addition or dredging to a control. A 360-day field investigation indicated that LMB addition more effectively reduced pore water P concentrations and sediment P fluxes than dredging in comparison with the control. On average, dredging and in situ LMB inactivation reduced the P flux by 82% and 90%, respectively relative to the control sediment. Whilst both the LMB inactivation and dredging can reduce the mobile P concentration, the impact of LMB in reducing mobile P was demonstrated to be more prolonged than that of dredging after 360 days. The P fraction composition in the LMB inactivated sediment differed significantly from the dredged and control sediment. Contrary to physical removal of dredging, chemical transformation of sediment mobile P and Al-P into Ca-P is the main function mode of LMB for sediment internal P control. Both LMB addition and dredging caused changes in the composition of sediment bacterial communities. Whilst LMB addition increased bacterial diversity, dredging temporarily reduced it. This study indicates that in situ inactivation by LMB is superior to dredging in the long-term control of sediment P loading.

In this paper a micromechanical modelling method is developed to investigate the mechanical behaviour of the aluminium foam. A new Representative Volume Element (RVE) model denoted as ORVE is proposed based on thin-walled close octadecahedron cells, and then finite element models of these ORVEs are developed for the numerical modelling of the mechanical behaviour of the aluminium foam. The developed numerical model is validated by comparing the computed stress-strain relationship to that from experiments from literatures. The effect of compressing air on the compressive stress is also investigated and it is found that it can be neglected. An intensive parametric investigation is consequently conducted to study the effect of cell size and relative density on the mechanical behaviour of the aluminium foam based on the ORVE model. It is found that the mechanical behaviour of the aluminium foam depends mainly on the relative density/porosity or the ratio of cell wall thickness to cell height. The size of the cell is found to affect the Young's modulus but not the yielding strength, and for the aluminium foam of the same porosity, the Young's modulus slightly goes up with the increase of cell height. It is also found that the mechanical behaviour of the foam is not sensitive to the strain rate. In addition, a relationship between porosity and mechanical properties of the foam is proposed based on the ORVE model.

The stresses, related to rows and accumulations of dislocations were revealed by photoelastic method for ZnGeP2 crystals, grown by Vertical Bridgman method. A comparison of information from topographs of photoelastic method and X-Ray topography based on Borrmann method was carried out. It was shown that the strongest contrast is observed on boundaries of dislocation rows and regions of relatively perfect crystals. Photoelastic method gives information about defect structure, where X-Ray topography can not be applied because of high density of defects and disorientation of reflection planes. Because of high sensitivity of photoelastic method the images of defects have larger size then in X-Ray topography. That is why in ZnGeP2 predominately the total contrast from dislocation rows is fixed. However, in low angle boundaries photoelastic images of separate dislocations were revealed. By comparison with results of simulation it was stated that they are created by edge dislocation of slip system { 1 ¯ 10 } 〈 110 〉 , what confirms the data, obtained by Borrmann method. Thus, photoelastic method can be from one side a simple and express method of analysis of ZnGeP2 plates cut along the plane of optical isotropy (001), and from other side an analytical method of identification of dislocations and other defects in this material.

The solubility of pronamide in five organic solvents (ethanol, methanol, isopropanol, toluene and cyclohexane) at the temperature range from (278.15 to 323.15) K was measured by a dynamic equilibrium method. The results showed that the solubility of pronamide increased with the increasing temperature in all the solvents involved. The experimental values were correlated by the Apelblat equation, and a good fitting result was confirmed by the low level of root-mean-square deviations ( −4 ). Moreover, the apparent dissolving enthalpies and entropies, were derived from simplified van’t Hoff equation. The positive values of enthalpies and entropies revealed that the dissolution of pronamide in the selected solvents was an endothermic and entropy-driven process.

A red LiInSe2 crystal with 20 mm in diameter and a yellow LiInSe2 crystal with 30 mm in diameter were obtained by the vertical gradient freezing method in a two-zone furnace. The thermal annealing technologies in different atmospheres were investigated. The thermal and optical properties were characterized by simultaneous differential scanning calorimetric/thermo-gravimetric (DSC-TG) analysis and an infrared (IR) spectrophotometer. Four as-grown and annealed wafers whose colors changed from red to yellow were discussed in detail on the basis of IR spectra. The results demonstrate that the transparent range of all LiInSe2 samples is from 0.6 μm to 13.5 μm. The thermal annealing processes both in vacuum and in LiInSe2 polycrystalline can obviously reduce the optical losses of red crystals. The optical losses of the deep red annealed crystal is at the level of 0.1 cm−1 in the range 2.0–8.5 μm. The yellow as-grown crystals exhibit a better transmittance especially in near IR range by comparison with red crystals.

In this paper a hierarchical multiscale modelling method is proposed to analyse the strain-hardening and multiple-cracking tensile fracture behaviour of engineered cementitious composites. A simplified multi-linear crack bridging relationship is proposed at a lower mesoscale based on analytical crack bridging analysis for a single crack. A representative volume element model is developed at an upper mesoscale accounting for random fluctuations of internal material properties and sequentially occurred cracking, and it is analysed using the extended finite element method. The multiscale modelling method is validated, and the effect of fibre distribution uniformity on the tensile behaviour of ECC is investigated.