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• Energetic sea ice drift occurs under negative phase of Arctic Oscillation with positive phase of Arctic Dipole. • Wind-ice stress dominates ice floes away from islands and continents. • Balance exists between internal ice stress and sea surface height gradient in thick multiyear ice zone. By analyzing an Arctic ice-ocean coupled simulation, we study the linkage between wintertime sea ice drift and atmospheric circulation, and interpret the driving force terms in the sea ice dynamic equation. Sea ice drift anomaly is featured by an anticyclonic (cyclonic) gyre when regulated by negative (positive) phase of Arctic Oscillation with positive (negative) phase of Arctic Dipole, and a quasi-meridional stream from Chukchi-Beaufort (Barents-Kara) Seas to Barents-Kara (Chukchi-Beaufort) Seas when regulated by positive (negative) phase of Arctic Oscillation with positive (negative) phase of Arctic Dipole. Sea ice drift anomaly, when regulated by the mode alone, resembles spatial pattern of leading atmospheric mode. Decomposing sea ice dynamical equation shows that wind-ice stress dominates sea ice drift in areas away from islands and continental coastlines, ocean-ice stress acts as a resistant power to partly cancel the wind-ice stress in these areas, while in the coastal areas such as the thick multiyear ice zone north of the Canadian Arctic Archipelago, the wind-ice and ocean-ice stresses are small, the balance exists between sea surface height potential gradient and internal ice stress divergence. Developing more sophisticated internal ice stress expression in ice model is of great important to correctly project future sea ice change for the ice modeling community. [ABSTRACT FROM AUTHOR]

Despite extensive research into lead-free ceramics to achieve excellent dielectric properties and good energy storage performance, the primary challenge of low energy density remains unresolved. Here, a relaxor ferroelectric (1- x)Ba 0.7 Sr 0.3 TiO 3 - x Bi(Mg 0.5 Ti 0.5)O 3 [(1- x)BST- x BMT] was designed and prepared using a solid-state method, where x = 0.05, 0.15, 0.20, 0.25. It revealed that the introduction of BMT reduces the average grain size, resulting in a decrease and broadening of the dielectric constant peaks. This modification enhanced the breakdown field strength (E b) of BST ceramics. An effective energy storage density of 2.44 J/cm³ and an energy storage efficiency of 76.25 % ware achieved in 0.80BST-0.20BMT ceramic at an electric field of 300 kV/cm. Furthermore, the recoverable energy density and energy efficiency of the 0.80BST-0.20BMT ceramic exhibited excellent frequency stability over a frequency from 5 Hz to 500 Hz. A power density (P D ∼16.06 MW/cm³) and a short discharge time (t 0.9 ∼0.95 μs) were demonstrated in 0.80BST-0.20BMT ceramic at 200 kV/cm. [ABSTRACT FROM AUTHOR]

In the "digital age", children have widespread access to electronic devices, potentially impacting inhibitory control (IC) development. We examined this association at both the behavioral and neural levels with two experiments. In Experiment 1, we assessed 188 participants (91 girls), averaging 37.74 months old, using maternal self-report questionnaire for screen time and Day-Night Task for IC measurement. In experiment 2, we evaluated 42 participants (24 girls), averaging 41.24 months old, using maternal self-report questionnaires for screen time, a modified version Flanker task for IC, and functional near-infrared spectroscopy (fNIRS) to measure neural activity during IC task. Results from Experiment 1 indicated a negative correlation between young children's screen media use time and IC, with high users performing worse IC performance than low users. Experiment 2 confirmed these findings and revealed marginally reduced activation in the left PFC among high users compared to low users, with a moderate effect size and weak supporting evidence. These preliminary results underscore a detrimental association between screen media use and IC, emphasizing the significance of restricting screen exposure in young children to prevent overexposure. Further studies with larger sample sizes are needed to validate these results and draw causal conclusions. • Child screen media use time was negatively associated with inhibitory control. • High screen media user group (≥1 h/day) performance worse during inhibitory control task than low user group (<1 h/day). • High screen media user group had marginally lower activation in the PFC than the low user group. [ABSTRACT FROM AUTHOR]

Early determination of the prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is important to guide clinical management and decrease mortality. The aim of this study was to develop a new simplified prognostic score to accurately predict outcomes in patients with HBV-ACLF. Prospective clinical data from 2,409 hospitalized patients with acute deterioration of HBV-related chronic liver disease were used to develop a new prognostic score that was validated in an external group. A total of 954 enrolled patients with HBV-ACLF were diagnosed based on the Chinese Group on the Study of Severe Hepatitis B-ACLF (COSSH-ACLF) criteria. Six predictive factors were significantly related to 28-day mortality and constituted a new prognostic score (=1.649×ln(international normalized ratio)+0.457×hepatic encephalopathy score+0.425×ln(neutrophil)+0.396×ln(total bilirubin)+0.576×ln(serum urea)+0.033×age). The C-indices of the new score for 28-/90-day mortality (0.826/0.809) were significantly higher than those of 4 other scores (COSSH-ACLF, 0.793/0.784; CLIF-C ACLF, 0.792/0.770; MELD, 0.731/0.727; MELD-Na, 0.730/0.726; all p <0.05). The prediction error rates of the new score for 28-day mortality were significantly lower than those of the 4 other scores: COSSH-ACLF (15.9%), CLIF-C ACLF (16.3%), MELD (35.3%) and MELD-Na (35.6%). The probability density function evaluation and risk stratification of the new score also showed the highest predictive values for mortality. These results were then validated in an external cohort. A new prognostic score based on 6 predictors, without an assessment of organ failure, can accurately predict short-term mortality in patients with HBV-ACLF and might be used to guide clinical management. Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a complex syndrome that is associated with a high short-term mortality rate. We developed a simplified prognostic score for patients suffering from this condition based on a prospective multicentre cohort. This new score had better predictive ability than 4 other commonly used scores. [Display omitted] • We developed a new prognostic COSSH-ACLF II score based on 6 predictors from a large cohort. • This score simplifies triage and can be used to stratify patients with HBV-ACLF based on their short-term mortality risk. • The new score has improved prognostic accuracy and sensitivity for patients with HBV-ACLF. • This score could be used to guide clinical management and reduce the currently unacceptable mortality rate. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) have been widely applied to various fields, facing mass imagery data, object detection in UAV imagery is under extensive research for its significant status in both theoretical study and practical applications. In order to achieve the accurate object detection in UAV imagery on the premise of real-time processing, a coarse-to-fine object detection method for UAV imagery using lightweight convolutional neural network (CNN) and deep motion saliency is proposed in this paper. The proposed method includes three steps: (1) Key frame extraction using image similarity measurement is performed on the UAV imagery to accelerate the successive object detection procedure; (2) Deep features are extracted by PeleeNet, a lightweight CNN, to achieve the coarse object detection on the key frames; (3) LiteFlowNet and objects prior knowledge is utilized to analyze the deep motion saliency map, which further helps to refine the detection results. The detection results on key frames propagate to the temporally nearest non-key frames to achieve the fine detection. Five experiments are conducted to verify the effectiveness of the proposed method on Stanford drone dataset (SDD). The experimental results demonstrate that the proposed method can achieve comparable detection speed but superior accuracy to six state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Since azoxymethane (AOM)-dextran sodium sulfate (DSS) induced tumorigenesis was used to explore inflammation-associated carcinogenesis of sporadic colorectal cancer (CRC), different administration modes of AOM or DSS have been reported. In this article we optimized the protocol of the AOM-DSS modeling using C57BL/6 mice for study on sporadic CRC by intraperitoneal injecting AOM solution at a proper concentration with a 100 μl sterile syringe once, feeding with DSS solution for 7 days in a roll and change DSS solution every day. More than 100 C57BL/6 mice had been treated with the optimized protocol, and all mice were demonstrated suffering from colorectal tumors when sacrificed in 8 to 20 weeks after AOM injection. These tumors mainly occurred in distal segment of colorectum with an increase in tumor density, which was similar to CRC in human beings. Tumor per mouse was high, and variation of tumor number per mouse was low. The histology of tumor developed through the defined stage ranged from precursor lesions, adenomatous lesions, adenomas to adenocarcinomas. The modified protocol of AOM-DSS model is easy, cheap, with high tumor formation rate of colorectal tumors. [ABSTRACT FROM AUTHOR]

The triple-shape memory effect (triple-SME) in amorphous polymers arises from the heterogeneous glass transitions of different components. However, due to the complex composition and structural relaxation of triple-shape memory polymers (triple-SMPs), existing models struggle to characterize the shape memory temperature range for each component and its dependence on thermal history. This presents a challenge in developing a kinetic criterion to judge the occurrence of the triple-SME. To address this issue, we propose a kinetic phase transition model to predict the shape memory temperature range for each transition phase in triple-SMPs under different thermal histories. By combining the Tool-Narayanaswamy-Moynihan (TNM) model with the Adam-Gibbs theory, the effect of cooling rate during programming on subsequent triple-SME is investigated. Subsequently, the effectiveness of the proposed model is evaluated by applying it to predict the shape memory performance and thermomechanical behavior of SMPs with dual- and triple- SMEs under different thermal histories. Using this modeling strategy enables the calculation of the critical isothermal shape recovery time for each transition phase under different thermal histories, effectively preventing shape recovery overlap. Consequently, the proposed model is expected to provide theoretical guidance for designing SMPs with triple-SME and promoting their application in engineering. [Display omitted] • Propose a kinetic criterion for the triple-shape memory effect in amorphous polymers. • Build a kinetic phase transition model for heterogenous glass transitions in amorphous polymers. • Investigate the significant role of thermal history on the triple-shape memory behavior of amorphous polymers. • Compare the model with two set of experiments under different thermal histories. [ABSTRACT FROM AUTHOR]

To generate new wheat breeding lines, ultra-high pressure (UHP) (using castor oil as the medium) was used to induce mutant lines from the wheat variety ‘Yanzhan 4110′. Three high-yielding mutant lines (Gaoya 2, Gaoya 3 and Gaoya 9) were selected from 1580 mutants induced by UHP and were evaluated for agronomic and photosynthesis-related traits in this study. Our results showed that these mutant lines retained higher grain yield than Yanzhan 4110 and exhibited higher biomass and harvest index, significantly higher plant height, spikelet numbers per spike and higher kernel numbers per spike but similar or lower thousand-kernel weight (α = 0.05). The reading of relative leaf chlorophyll content (SPAD) and photosynthetic traits of the high-yielding mutant lines varied to different degrees. The mutant lines had higher SPAD and higher stomatal conductance (Gs) than Yanzhan 4110 at two grain-filling stages. The net photosynthetic rate (Pn), apparent mesophyll conductance, Gs and transpiration rate (Tr) of Gaoya 2 were significantly higher than those of Yanzhan 4110 at the mid grain-filling stage (GF-2) (α = 0.05). The decreases in SPAD, Pn, Gs, transpiration efficiency (TE) and Tr in the high-yielding mutant lines were smaller than those in Yanzhan 4110 during the early grain-filling stage (GF-1) and GF-2. Fluorescence parameters, including F0, Fm, Fv, Fv/F0, and Fv/Fm, were higher in the three high-yielding mutant lines, while qN was significantly lower at GF-1 and GF-2 compared with those in Yanzhan 4110 (α = 0.05). Higher qP and ΦPSII values were also observed in the three high-yielding mutant lines. These results indicate that wheat mutations induced by UHP exhibited high yield, improved photosynthetic efficiency, decreased thermal dissipation and altered photoinhibition. [ABSTRACT FROM AUTHOR]

Introduction: Although executive function (EF) is widely considered crucial to several aspects of life, the mechanisms underlying EF development remain largely unexplored, especially for infants. From a behavioral or neurodevelopmental perspective, motor and general cognitive abilities are linked with EF. EF development is a multistage process that starts with sensorimotor interactive behaviors, which become basic cognitive abilities and, in turn, mature EF.Objectives: This study aims to examine how infant motor and general cognitive abilities are linked with their EF at 3 years of age. This work also aims to explore the potential processes of EF development from early movement.Methods: A longitudinal study was conducted with 96 infants (55 girls and 41 boys). The infants' motor and general cognitive abilities were assessed at 1 and 2 years of age with Bayley Scales of Infant and Toddler Development, Second and Third Editions, respectively. Infants' EFs were assessed at 3 years of age with Working Memory Span task, Day-Night task, Wrapped Gift task, and modified Gift-in-Bag task.Results: Children with higher scores for cognitive ability at 2 years of age performed better in working memory, and children with higher scores for gross motor ability at 2 years performed better in cognitive inhibitory control (IC). Motor ability at 1 year and fine/gross motor ability at 2 years indirectly affected cognitive IC via general cognitive ability at 2 years and working memory.Conclusions: EF development is a multistage process that originates from physical movement to simple cognitive function, and then to complex cognitive function. Infants and toddlers can undergo targeted motor training to promote EF development. [ABSTRACT FROM AUTHOR]

Crop irrigation which results in high water use efficiencies typically uses science-based irrigation scheduling tools to determine irrigation application timing and quantities. Although a large variety of sensors are available for measuring soil moisture status, there are a few easy-to-use irrigation scheduling tools which provide a yes/no irrigation decision or recommend how much water should be applied to return the soil profile to an optimal soil moisture condition. The work described here developed a method which uses soil water tension data from soil moisture sensors and the van Genuchten model to provide irrigation scheduling recommendations. The strength of the method is that it can use data readily available from USDA-NRCS soil surveys to predict soil water retention curves and calculate the volumetric water content and soil water tension of a soil at field capacity. Those parameters are then used to translate measured soil water tension into irrigation recommendations which are specific to the soil moisture status of the soil. The method was validated by comparing its results to other published methods and with continuous soil water tension data with multiple wetting and drying cycles from six fields in southern Georgia, USA. Finally, the model was incorporated into a web-based irrigation scheduling tool and used in conjunction with a wireless soil moisture sensing system to schedule irrigation in a large commercial field during 2015. By the van Genuchten model, we used about two thirds of the irrigation water and produced about the same yields as a commonly used yes/no irrigation decision tool. The presented method can be used to build resiliency to climate variability because it provides growers with data which they can use to make informed decisions about managing their water resources. [ABSTRACT FROM AUTHOR]

Combinational sphere element method is introduced to simulate the mechanical behavior of cemented particulate composite. A pair of particles and the cement matrix in middle are extracted from the composite, and they constitute a combinational sphere element (CSE). The stiffness of a CSE on axial direction, tangential direction and bending direction can be derived based on the mechanical model and assumptions. The stress distribution function in matrix can also be gained when the CSE supports load on each direction. The element stiffness matrix of CSE is obtained through the direct method. The CSE can be described by an equivalent rigid beam-spring model according to the element stiffness matrix, so the composite can be described by an equivalent rigid beam-spring lattice. Finally, an example is taken out to show the application of this new method. Stress distribution function, stiffness on three directions and macro effective elastic constants of composite can be obtained. The results agree well with the simulation results of the representative volume element. According to the damage criterion set reasonably, the damage evolution of the models with defects can be simulated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Vector deformation, adjustable over a wide area under uniaxial loads, was controlled by the chiral cells' geometric parameters. The chiral cells' deformations were summed as vector additions. • Structures with various coupling deformation properties were designed, such as compression to dislocation and compression to bending. • A variable-geometry wing was designed. • Based on a genetic algorithm, an active design method was used to encode target deformations into the structures. Chiral cell structures have the potential to transform the robot design field because of the structures' ability to adopt various deformations under uniaxial load, such as twisting and a negative Poisson's ratio. The rationale that underpins this potential is asymmetric deformation that is similar to shearing; such a deformation has vector characteristics. In this paper, several cellular structures were designed that deformed the cell structure in many ways under uniaxial load, in accordance with the deformation vector addition principle of chiral cells (such as compression–dislocation, compression–bending coupling deformation, and variable wings with forward and backward sweep functions)—which were verified by finite-element analyses and experiments. With a given objective deformation, a genetic algorithm was introduced to encode structures with various chiral cells, and the feasibility of the method was verified through several examples. The research herein shows that structures with various deformation demands can be designed through reasonable assembly of chiral cells, which has potential applications to the field of variant structures design. [ABSTRACT FROM AUTHOR]

The present study examined bidirectional effects between sleep problems (nocturnal awakenings and insufficient nocturnal sleep) and infant development (gross motor, fine motor, and cognition) in a sample of 182 infants (89 girls) and their parents living in Beijing (China). Using 3 waves of longitudinal data (at 6 months, 1 year, and 2 years of age), this study (a) explored the differences in sleep patterns and developmental outcomes between infants in the current sample and infants from other cultures; and primarily examined (b) whether nocturnal awakenings and insufficient nocturnal sleep prospectively predicted infant development; (c) or whether infant development predicted sleep problems. Mothers reported their children's sleep problems, and infant development was assessed with Bayley III. Sleep patterns of Beijing infants were slightly different from those from Finland and Singapore, and most scores on Bayley III in this Beijing sample were higher than those in Danish, Dutch and Sri Lankan samples. Sleep problems and developmental measures were stable across the 3 times of assessments, but cross-lagged associations were limited in number and strength. High scores on the Bayley at 6 months predicted less nocturnal awakenings at 1 year of age. Insufficient nocturnal sleep at 1 year predicted poor fine motor development at 2 years. Thus, findings suggest some bidirectional associations between infant development and sleep problems and further highlight the need to understand these relations within specific cultural contexts. [ABSTRACT FROM AUTHOR]

The aerodynamic performance and wake dynamics of wind turbines are known to be affected by platform surge motion. This study utilized an improved delayed detached eddy simulation combined with the overset grid method to investigate the effect of surge motion amplitudes and periods (frequencies) on the aerodynamics and wake instabilities of wind turbines. The effect of the Reynolds number and azimuthal increment sensitivity analysis (time step) on the wind turbine loads and flow fields were investigated in detail. A comparison of the mean loads of the power coefficient and thrust coefficient between the numerical simulation and experiment with a consistent Reynolds number shows that the grid and simulation parameters used in this study can accurately capture the flow field and aerodynamic performance of the wind turbine. A detailed analysis of the flow fields, wake vortex structure, and mean Reynolds stress distribution was utilized to explore the effect of surge motion amplitudes and periods on the wind turbine performance, as well as the mechanism of the wake instability. Our results indicate that the surge motion can improve the efficiency of power generation and promote wake instabilities and vortex interactions. Meanwhile, surge motion amplitudes and frequencies have a positive effect on the wake recovery. • IDDES is employed to model aerodynamics performance and wake dynamics of OFHAWT under surge motion. • The flow field near the blade and wake region is analyzed in detail. • Surge motion promotes the wake instabilities and vortex interaction. • Surge motion amplitudes and frequencies have a positive effect on the wake recovery process. [ABSTRACT FROM AUTHOR]

The vortex-induced vibration of various aspect ratio (AR = 0.75 , 1.0 , 1.25 and 1.5) ellipse cylinders with convective heat transfer is investigated at Re = 150 and m ∗ = 10 for 3 ≤ U r ≤ 12 , where U r = U / (f n D) and f n is the natural frequency of cylinder in still air. The amplitude and frequency response of displacement, force and the Nusselt number are presented and discussed, the vorticity, temperature contours and wake patterns are studied to understand the effect of AR and U r on the 1DOF vibration characteristics and the heat transfer of the isothermal cylinder. The results show that the classical Karman shedding (2S) is observed at relative low displacement and the C(2S) occurs when the cylinder undergoes high-amplitude oscillations for the AR considered, and the P+S wake mode which is composed with a single vortex and one pair of counter-rotating vortices during the transition from the initial branch to the VIV lock-in regime. There are multiple frequencies related to the response of Nusselt number, with the 2 S t N u dominating. And the maximum value of N u A is 11.07, 11.7, 12.1 and 12.35 for AR = 0.75 , 1.0 , 1.25 and 1.5 respectively, which are increased by 7%, 8.7%, 11% and 13.5%, respectively, compared with the corresponding stationary cylinders, indicting an enhanced heat transfer of VIV cylinder. As increasing of the AR to 1.5, an early exit of the VIV lock-in regime and into the desynchronized regime happens due to the strong 2 S t n in the lift frequency response when. [ABSTRACT FROM AUTHOR]

Abstract: The cement manufacturing sector is the second largest source of anthropogenic greenhouse gas emissions in the world. Carbon Capture and Storage (CCS) is one of the most important technologies to decarbonise the cement manufacturing process. China has accounted for more than half of global cement production since 2008. This study suggests criteria to assess the potential to retrofit cement plants and analyses the economics of retrofitting cement plants for CCS with a case study of a modern dry process cement plant locating in Guangdong province, China. The study assumes the extra heat and power for CO2 capture and compression is provided by a new 200MW combined heat and power unit (CHP) (US$17.5/MWh thermal for the cost of coal). The estimated cost of CO2 avoidance by retrofitting a cement plant for carbon capture in 2012 is US$70/tonne at a 14% discount rate with 25years remaining lifetime. Through a stochastic cash flow analysis with a real option model and Monte Carlo simulation, the study found the value of an option to retrofit to be US$1.2million with a 7.3% probability of economic viability. The estimate is very sensitive to the assumptions in the carbon price model (i.e. base carbon price is US$12.00/tCO2e in 2012 and the mean growth rate is 8%). The option value and the probability can reach US$20 million and 67% respectively, if a 10% mean carbon price growth is assumed. Compared with post-combustion carbon capture retrofitting prospect in existing coal-fired power plants, the economics of retrofitting cement plants to carbon capture is less attractive. However, given the uncertainties in climate policy, regulation and carbon market, new-build cement plants in China, with long lifetime, should consider an essential level of “CCS Ready” to reduce the cost of retrofit and keep the retrofitting option open. [Copyright &y& Elsevier]

Abstract: China is building more than 1GW of advanced coal-fired power plants every week. This interdisciplinary study investigates the technical and economic performance of retrofitting a 1000MW ultra supercritical pulverised coal-fired (USCPC) power plant locating at Shandong province in China. An ASPEN simulation model is designed to estimate the energy output penalty at different levels of capture. The retrofitted system consists of the conventional power generation unit, the additional post-combustion unit and other associated extra equipments. The ASPEN simulation results show that the efficiency penalty is approximately 8.6% for a 90% capture rate and 6% for a 50% capture rate in this retrofitting study. In addition, the simulation result of the process model is applied to analyse the value of retrofitting flexibility and the economic-viable chance of retrofitting the underlying project through a real option analysis model. The economic model reveals that the value of retrofitting option in the 1GW USCPC power plant reaches US$76 million and that a 40% economic viable possibility of retrofitting to capture CO2 in its remaining 26years lifetime under the hypothetical baseline scenario. The significant economic benefits of retrofitting an existing USCPC plant to CO2 capture implies the urgency to conduct a detail survey on the retrofitting prospect of Chinese coal-fired power plants and develop a guideline to maintain their retrofitting options open. [Copyright &y& Elsevier]

Abstract: China has been building approximately 1 GW of new coal-fired power plant per week since 2005. Power plants now in construction may continue to operate until 2040. “CCS (Carbon Capture and Storage) Ready” enables and eases the subsequent retrofitting of a plant to be able to capture carbon dioxide later in that plant’s lifetime. Building on the definitions of the IEA GHG (IEA Greenhouse Gas Programme) and GCCSI (Global Carbon Capture and Storage Institute), this study suggests a novel concept ‘CCS Ready Hub’ for implementing CCS Ready. A CCS Ready Hub not only includes a number of new coal-fired power plants but also integrates other existing stationary carbon dioxide emissions sources into the planning for potential infrastructure. We conducted a case study of Guangdong province in China with a detailed engineering and economic assessment in Shenzhen City. The study first reviewed the potential storage sites and analysed the existing stationary emissions sources in Guangdong using a GIS (Geographic Information System) approach. Thereafter, we focused on investigating the economic benefits of a ‘CCS Ready Hub’ at a potential 4 GW new USCPC (ultra-supercritical pulverised coal-fired) power plant in Shenzhen. Using the cost of carbon dioxide avoidance in 2020 as a criterion, we found that the concept of a CCS Ready Hub to finance CCS Ready at a regional planning level rather than at an individual plant is preferred since it significantly reduces the overall cost of building an integrated CCS system to reduce carbon emissions in the future. [Copyright &y& Elsevier]

Abstract: We present results of a major survey of Chinese opinion leaders conducted from March to April 2009, supported by EU–UK–China near zero emissions coal (NZEC) initiative. Respondents were drawn from 27 provinces and regions using an online survey with follow-up face-to-face interviews. A total of 131 experts and decision-makers from 68 key institutions were consulted through online survey. This survey is the first to focus on demonstration projects in particular and is the most geographically diverse. We aim to understand perceptions of applying CCS technologies in the first large-scale CCS demonstration project in China. Though enhanced oil recovery (EOR) and enhanced coal bed methane recovery (ECBM) may not be long-term solutions for CO2 storage, they were viewed as the most attractive storage technologies for the first CCS demonstration project. With regard to CO2 capture technology, on the whole, post-combustion (which would be most applicable to the vast majority of existing power plants which are pulverised-coal) received slightly higher support than pre-combustion. More surprising, respondents from both the power and oil industries favoured pre-combustion. There was no consensus regarding the appropriate scale for the first demonstration. A large number of respondents were concerned about the energy penalty associated with CCS and its impact on the long-term sustainability of coal supply in China, although such concerns were much reduced compared with surveys in 2006 and 2008. [Copyright &y& Elsevier]

Summary: Plant leaf can absorb water when the leaf is in contact with water. This happens when the rainfall is intercepted by plant leaves, where the intercepted part of rain remains on the leaf surface. When the intercepted water is either absorbed or subsequently evaporated into the atmosphere, the plant leaves can dissipate water through the desorption process until the plant is dry or rewatered. In this paper, two symptomatic models in the form of exponential functions for leaf water absorption and leaf water desorption were derived and validated by experimental data using leaves of three turfgrasses (Tall fescue, Perennial ryegrass and Kentucky bluegrass). Both the models and measured data showed that the rate of leaf water absorption was high at the low initial leaf water content and then gradually leveled off toward the saturated leaf water content. The rate of leaf water desorption was high at the high initial leaf water content then decreased drastically over time toward zero. The different plant leaves showed different exponents and other parameters of the functions which indicate the difference of plant species. Both the absorption and desorption rates were relatively higher for the Kentucky bluegrass and lower for the Tall fescue and Perennial ryegrass. The concept of specific leaf area (SLA) was used to understand the saturated leaf water content (Cs ) of the three turfgrasses. Linear relationships were found between Cs and SLA. The leaf water absorption and desorption functions are useful for deriving physiological parameters of the plant such as permanent wilting leaf water content, naturally irreducible leaf water content, exponential leaf water absorption coefficient, and exponential leaf desorption coefficient, as well as for evaluating the effects of rainfall interception on plant growth and water use efficiency. [Copyright &y& Elsevier]

Abstract: Manganese cobalt oxides with different Co/Mn ratios have been prepared by co-precipitation methods, and their catalytic performance on methane combustion were evaluated from 250°C to 400°C at a space velocity of 36,000h−1. A significant improvement of activity was observed over Co5Mn1 catalysts with a Co/Mn molar ratio of 5:1, and the catalytic activity reached 90% of methane conversion at 320°C. Oxygen mobility – reflected by the appearance of O2 − – was probably a key factor that influenced the oxidation rate of methane below 320°C. The doping of manganese into the spinel structure of cobalt oxide increased crystal defections, which probably caused the increase of the amount of octahedrally coordinated divalent cobalt cations that are responsible for catalytic activity. The hydroxyl groups observed on the manganese-doped catalysts would also explain the promotional effects. [Copyright &y& Elsevier]

Abstract: Flying optics technologies are used for a range of applications such as a large workpiece processing and laser texturing. It is essential to compensate the variations of laser beam focus parameters while the focus head is moving. A flying optics automatic compensation approach is proposed to achieve invariable laser focal size, focus depth and focus position through computer controlled objective lens and focus lens position. A simple mechanical control method is also presented for the realization of constant beam parameters for flying optics. Numerical simulation is illustrated for a CO2 laser texturing application. The flying optics parameters compensation is simple and easy to control. [Copyright &y& Elsevier]

Abstract: A new Ru(II) complex [Ru(phen)2(mdpz)]2+ (phen=1,10-phenanthroline, mdpz=7,7′-methylenedioxyphenyl-dipyrido-[3,2-a:2′,3′-c]phenazine) has been synthesized and characterized in detail by elemental analysis, mass spectrometry and 1H NMR spectroscopy. The interaction of the complex with calf thymus DNA was investigated by spectroscopic and viscosity measurements. The results suggest that the complex binds to DNA via an intercalative mode and serves as a molecular “light switch” for DNA. Moreover, the complex has been found to promote the photocleavage of plasmid DNA pBR322 under irradiation at 365nm. The mechanism studies reveal that singlet oxygen (1O2) plays a significant role in the photocleavage. [Copyright &y& Elsevier]

The creation of a market for steel produced by less carbon-intensive production processes, here called 'green steel', has been identified as a means of supporting the introduction of breakthrough emission reduction technologies into steel production. However, numerous details remain under-explored, including exactly what 'green' entails in the context of steelmaking, the likely competitiveness of green steel products in domestic and international markets, and potential policy mechanisms to support their successful market penetration. This paper addresses this gap through qualitative research with international sustainability experts and commercial managers from leading steel trade associations, research institutes and steelmakers. We find that there is a need to establish a common understanding of what 'greenness' means in the steelmaking context, and to resolve various carbon accounting and assurance issues, which otherwise have the potential to lead to perverse outcomes and opportunities for greenwashing. We identify a set of potential demand-side and supply-side policy mechanisms to support green steel production, and highlight a need for a combination of policies to ensure successful market development and avoid unintended consequences for competition at three different levels: 1) between products manufactured through a primary vs secondary steelmaking route, 2) between 'green' and traditional, 'brown' steel, and 3) with other substitutable materials. The study further shows that the automotive industry is a likely candidate for green steel demand, where a market could be supported by price premiums paid by willing consumers, such as those of high-end luxury and heavy-duty vehicles. [ABSTRACT FROM AUTHOR]

The current research attempts to describe the association between the aerodynamic drag and flow structures induced by train running in time-averaged and time-dependant views. A ICE2 train model is used as the research object, with the flow field solved by Large Eddy Simulation (LES). The validation is carried out through comparison with existing research data, and grid independence study in terms of time-averaged and second-order statistics. Numerical results are firstly presented by description of the time-averaged near wake flow topology based on surface flow visualization. Then, the wake integration method is used both time-averaged and instantaneously to link the aerodynamic force with integrated flow quantities on different wake planes: from the time-averaged perspective, the contribution of different flow terms to total drag is presented and compared; from the instantaneous perspective, the overall wake variation tendency is linked to the fluctuating component of aerodynamic force, based on the wake convection velocity and downstream distance of wake planes. The dynamic features of flow quantities in different locations are presented, with cross-correlation method used to describe the correlation between fluctuating aerodynamic drag and wake motion. Approaches and findings presented in the current study could serve as fundamentals which support future study. • Large eddy simulation employed to solve flow field around a generic ICE2 high-speed train model. • Surface flow visualization techniques utilized to illustrate the time-averaged near wake flow topology. • Wake integration method applied to link the aerodynamic force with integrated flow quantities on different wake planes. • Dynamic features of flow quantities presented, with cross-correlation method used to describe correlation between aerodynamic drag and wake motion. [ABSTRACT FROM AUTHOR]

Abstract: Al-SBA-15 was prepared by one-step hydrothermal synthesis method, and was characterized by X-ray diffraction, N2-adsorption, transmission electron microscope and Fourier infrared spectra of chemisorbed pyridine (Py-IR). The results showed that Al-SBA-15 had well-ordered hexagonal mesopores. As compared with Si-SBA-15, Al-SBA-15 had thicker pore wall, higher surface area, and stronger Lewis acidity. Due to the stronger Lewis acidity, Mn/Al-SBA-15 catalyst prepared by impregnation showed better activity than Mn/Si-SBA-15 in the selective catalytic reduction of NO by NH3. [Copyright &y& Elsevier]

Abstract: Mifepristone is a non-selective antagonist of 3-oxosteroid receptors with both abortifacient and anti-endometriotic activities. Non-steroidal mimetics of mifepristone and progesterone are important templates for modulation of the progesterone receptor (PR). For our PR program, we sought an unexplored, synthetically accessible non-steroidal mimetic of mifepristone, suitable for parallel synthesis of analogues. Docking of compounds into a PR homology model identified 4-substituted pyrazolines, which, when synthesized and tested, exhibited functional antagonism of PR. [Copyright &y& Elsevier]

Electroacupuncture (EA) has been used in China for many years to treat Parkinson’s disease (PD) with reportedly effective results. However, the physiological and biological mechanism behind its effectiveness is still unknown. In the present study, different frequencies of chronic EA stimulation (0, 2, 100 Hz) were tested in a partially lesioned rat model of PD which was induced by transection of the medial forebrain bundle (MFB). After 24 sessions of EA stimulation (28 days after MFB transection), dopaminergic neurons in the ventral midbrain were examined by immunohistochemical staining, and brain-derived neurotrophic factor (BDNF) mRNA levels in ventral midbrain were measured by in situ hybridization. The results show a marked decrease of dopaminergic neurons on the lesioned side of the substantia nigra (SN) comparing with the unlesioned side. Zero Hz and 2 Hz EA stimulation had no effect on the disappearance of dopaminergic neurons. However, after 100 Hz EA, about 60% of the tyrosine hydroxylase (TH)-positive neurons remained on the lesioned side of the SN. In addition, levels of BDNF mRNA in the SN and ventral tegmental area (VTA) of the lesioned side were significantly increased in the 100 Hz EA group, but unchanged in the 0 and 2 Hz groups. Our results suggest that long-term high-frequency EA is effective in halting the degeneration of dopaminergic neurons in the SN and up-regulating the levels of BDNF mRNA in the subfields of the ventral midbrain. Activation of endogenous neurotrophins by EA may be involved in the regeneration of the injured dopaminergic neurons, which may underlie the effectiveness of EA in the treatment of PD. [Copyright &y& Elsevier]

Inonotus obliquus (Fr.) Pilat is a mushroom belonging to the family Hymenochaetaceae. It is popularly called the Chaga mushroom in Russian folk medicine and has been used as a traditional medicine to treat diabetes mellitus in Eastern European and Asian countries. However, its effects on glycolipid metabolism disorders and underlying molecular mechanism of action remain unclear. I. obliquus contains abundant functional components, which provide potential medicinal value. The purpose of this study was to investigate compositions of I. obliquus extract with a high-pressure water extraction method, and investigate the anti-type 2 diabetic effects of I. obliquus extract and the possible underlying mechanisms involved. The I. obliquus was extracted by a high-pressure water extraction method, and tested its main components by special assay kit and instrumental analysis. Type 2 diabetic C57BL/6 mice were induced by high-fat diet with low-dose STZ injection, and were daily gavaged with different doses of I. o bliquus extract for 8 weeks. Glycemic, blood lipid profile, and histopathology of liver and pancreas were assessed. Underlying mechanisms related to glycemic control in liver were further performed. The I. obliquus extract main compounds were β-Glucans, triterpenoids and polyphenol by determination. Oral administration of 250 mg/kg and 500 mg/kg I. obliquus extract significantly alleviated blood glucose and insulin resistance. Moreover, 250 mg/kg and 500 mg/kg of I. obliquus extract increased liver glycogen content and high-density lipoprotein cholesterol (HDL-C) levels while decreased total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels. Furthermore, the protein expression levels of phosphatidylinositol-3 kinase (PI3K), p-protein kinase B (Akt), p-adenosine monophosphate activated protein kinase (AMPK), and p-acetyl-CoA carboxylase (ACC) were upregulated, whereas sterol regulatory element-binding protein-1c (SREBP-1c) and fatty acid synthase (FAS) were downregulated after supplement with 250 mg/kg and 500 mg/kg of I. obliquus extract. Interestingly, I. obliquus extract was a dose-effect relationship within a certain range. 250 mg/kg had obvious anti-diabetes effect, and the effect of 500 mg/kg dose was the same as that of metformin. I. obliquus extract ameliorated insulin resistance and lipid metabolism disorders in diabetic mice. The hypoglycemic and hypolipidemic properties of I. obliquus extract were supposedly exerted via the regulation of the PI3K/Akt and AMPK/ACC signaling pathways. [Display omitted] • I. obliquus extract were extracted by a high-pressure water method. • I. obliquus ameliorated insulin resistance and lipid metabolism disorders. • The hypoglycemic mechanism of I. obliquus was PI3K/Akt signaling pathway. • The hypolipidemia mechanism of I. obliquus was AMPK/ACC signaling pathway. [ABSTRACT FROM AUTHOR]

The improved delayed detached eddy simulation (IDDES) was used to study the influence of the platoon configuration of trains on its aerodynamic performance. CFD simulations were validated against the wind tunnel test and different mesh refinement to further verify the flow field around the high-speed train. The platoon configuration mainly affects the aerodynamic forces of the tail car of the front train (car3) and the head car of the rear train (car4) through flow interference. The surface pressure distribution of the train and the time domain and frequency domain characteristics of the aerodynamic force under different spacing are analyzed, and the changing law of the aerodynamic force and the lateral stability of the trains are summarized. The boundary layer and slipstream of trains in platoon are also compared with those of single trains. Meanwhile, both the time-averaged and instantaneous near-wake structures are compared for different cases. • IDDES k-w turbulence model is used to model the wake interaction and detailed flow field structure. • The aerodynamic force, slipstream, and boundary layer under different spacing are evaluated. • The dominant equivalent full-scale frequency (Hz) at 300 ​km/h lies between 1.87 and 3.33 ​Hz (0.09 ≤ S t ≤ 0.16). • The largest oscillating side forces for the car4 in platoon is 157.62 ​N. [ABSTRACT FROM AUTHOR]

The method of combining incompressible hybrid Reynolds average Navier–Stokes/large eddy simulation (RANS/LES) with an acoustic perturbation equation was studied to accurately predict the flow and noise performances in NASA tandem cylinder experiments. In this approach, acoustic waves simultaneously propagate in the time domain with an unsteady turbulent flow. The experiment was performed under the condition of a Reynolds number of 1.66 × 105, based on the cylinder diameter, which provided detailed surface pressure and flow field measurements. The improved delayed detached eddy simulation (IDDES) model established in this study was consistent with the experimental results, except for the flow field behind the rear cylinder, which was caused by an early separation relative to the experiment. The acoustic results showed that the rear cylinder dominated the noise radiation, which indicated that the pressure fluctuation caused by wake interference was greater than that caused by vortex shedding. Acoustic predictions were also obtained using an acoustic analogy approach based on the FH-W method. Three kinds of integral surfaces (PS-open, PS-close, and IPS) were made for the acoustic predictions using the Ffowcs Williams–Hawkings method. This study also showed that wavenumber decomposition could be utilised to quantify the mechanisms related to turbulent convection and sound propagation. An IDDES hybrid model for predicting near-field and far-field noise was established, which could be applied to practical engineering applications. • Incompressible IDDES combined with APE methodology for flow and noise predictions of the NASA Tandem Cylinder Experiment. • Different modal decomposition methods for identifying energetic coherent structures in flow field. • Acoustic predictions obtained and compared using FW-H method and APE method. • Wave-number decomposition used to quantify the mechanisms associated with turbulent convection and acoustical propagation. [ABSTRACT FROM AUTHOR]

The improved delayed detached-eddy simulation (IDDES) method based on the shear-stress transport (SST) κ-ω turbulence model was employed to investigate the ballast height influence on aerodynamic performance at Re ​= ​9.12 ​× ​106. Both time-averaged and instantaneous slipstreams and near-wake flow structures and associated slipstream velocity distributions are compared for four cases. Results reveal that the mean lift force coefficient decreases with increasing ballast height. At the Technical Specifications for Interoperability (TSI) trackside position, the maximum slipstream velocity with a ballast height of 1.825 ​m (Case 3) is 97.4%, 15.6% and 11.7% lower than with a ballast height of 0 ​m (Case 1), 0.825 ​m (Case 2) and 2.825 ​m (Case 4), respectively. The TSI values in Case 3 ​at both the trackside and platform positions are the lowest. In the wake region, increasing the ballast height greatly constrains the outward and downward movements of vortices. The slipstream velocity in the wake region in Case 3 is the lowest among all cases. In this study, we found that Case 3 greatly decreases the slipstream velocity around the train and improves the flow structure in the wake region, which reduces the risk to workers and equipment along the railway. • The CFD results were validated with wind tunnel experiment and found good agreement. • IDDES k-w turbulence model is used to model the detailed flow field structure. • The effect of height of ballast on the slipstream and wake dynamics of train is investigated. [ABSTRACT FROM AUTHOR]

The aerodynamic loads on the overhead bridge bottom surface induced by train passage are reported in this paper. Both moving model test and numerical simulation approaches at the 1:20 scale are used. The numerical work is validated through both mesh independence tests and comparison with experimental data. Typical pressure variation curves are plotted and compared with previous studies. The peak pressure values' dependence on the Reynolds number is considered through four sets of experiments with different train running speeds. The peak pressure coefficient distribution law for the bridge bottom surface is presented. Differences in the pressure distribution in different bridge bottom areas are explained based on more detailed flow field information. The influence of the bridge height on the aerodynamic load magnitude and time interval is presented. Moreover, the application of the CEN Standard to practical engineering issues is discussed. [ABSTRACT FROM AUTHOR]

Perennial bioenergy grasses can potentially replace fossil fuels and offset atmospheric CO 2 through soil C sequestration. However, limited information relevant to the impacts of bioenergy cropping on ecosystem services, especially above- and below-ground productivity and soil C sequestration is available for subtropical environments (e.g., southeastern USA). The objective of this study was to evaluate the impacts of perennial bioenergy cropping on C cycling and accumulation in the soil following four years of production in North Florida. Treatments consisted of six perennial grass species: giant reed, elephantgrass, energycane, sugarcane, sweetcane, and giant miscanthus. Elephantgrass, energycane, sweetcane, and sugarcane produced great shoot biomass (31–41 Mg ha−1) when harvested once per year. Giant reed's shoot biomass responded favorably to two harvests per year (27–43 Mg ha−1), whereas giant miscanthus did not perform well in any of the years (9–21 Mg ha−1). Additionally, giant reed, sweetcane, and giant miscanthus produced greater root biomass (9–11 Mg ha−1) compared with the other three species (2.5–3.2 Mg ha−1). Among the six grasses, sweetcane, energycane, and elephantgrass resulted in increases in soil C stocks (~15 Mg ha−1) relative to the initial level. Conversely, giant reed and giant miscanthus had no increase in soil C stock. Results suggested that interspecies differences observed in biomass yield among the six perennial bioenergy grasses could therefore affect soil C accumulation. High biomass yielding species such as sweetcane, energycane, and elephantgrass can effectively increase soil C within a few years following establishment in a subtropical environment. • Giant reed, sweetcane, sugarcane, energycane, and elephantgrass were able to produce high shoot biomass in North Florida. • Giant miscanthus could not produce comparable shoot biomass with other species in the subtropical environment. • Sweetcane, energycane, and elephantgrass exhibited significant increases in soil C stock over four growing seasons. • Sweetcane, energycane, and elephantgrass are able to provide multiple ecosystem services rapidly following establishment. [ABSTRACT FROM AUTHOR]

• A modified energy method is developed to study the properties of single-walled nanotubes. • The energy of a system is expressed by the force field functions of the molecular mechanics. • The temperature-dependent elastic property and strain energy of nanotubes are obtained. • The effect of tube diameter and inversion energy on the constants of nanotubes is significant. • The temperature has a greater effect on the tensile deformation of zigzag carbon nanotubes. A modified energy method is developed to investigate the elastic properties of single-walled carbon nanotubes. The energy of a system is expressed by the force field functions of the molecular mechanics. Under the assumption of a small deformation and the principle of minimum potential energy, the system function is established. In addition to consider the change of bond stretch and bond angle, the inversion energy is also proposed in this study. Based on the established model, the closed-form expressions of temperature-dependent Young's modulus, Poisson's ratio and strain energy of armchair and zigzag carbon nanotubes are obtained. The results show that the effect of tube diameter and inversion energy on the elastic constants of carbon nanotubes (CNTs) is significant when the tube diameter is small. Under different thermal expansion coefficients, the Young's modulus of carbon nanotubes varies nonlinearly with the temperature, whereas the Poisson's ratio is insensitive to the temperature. It is also found that the temperature has a greater effect on the tensile deformation of zigzag CNTs, which provides a more accurate theoretical foundation for the tensile fracture of CNTs in a thermal environment. [ABSTRACT FROM AUTHOR]

The pressure variations induced by a CRH380A EMU on a 2.15 m high bridge noise barrier are investigated in a field measurement. The familiar fluctuating pressure time history curves and the peak-to-peak pressure ( ΔP ) distributions attributing to the train head on the barrier surfaces are presented. A comparison of the positive head pulse pressure is made between the measurement results and the data calculated by empirical equations in EN 14067-4. Furthermore, the influences of train speed, train running lines, locations of measurement points, train marshalling length and environmental wind speed on ΔP are analysed. The results indicate as the train speed increases, the corresponding time intervals of ΔP decrease gradually, whereas their slopes become increasingly steep. For a CRH380A EMU, the aerodynamic length of the train head is between 7.63 and 7.64 m, which differs from the physical length of a realistic train with 12.00 m. Along the noise barrier from bottom to top, the ΔP values on the inner surface decrease with the increase of height, while these values on the outer surface increase. Taking the wind direction into account, the ΔP values are a little higher when the high-speed trains run against the wind direction. [ABSTRACT FROM AUTHOR]

By use of the theoretical method of density functional theory (DFT), we systemically investigate the chalcogen doped Cu 4 metal clusters (Cu 4 O, Cu 4 S, and Cu 4 Se) as catalysts for the electrochemical CO 2 reduction with toluene as solvent. These doped clusters have efficient catalytic properties which can reduce CO 2 to CH 4 and a small amount of CH 3 OH. In the case of CO 2 hydrogenation to CH 4 , the reaction barrier of the Cu 4 O cluster and Cu 4 S cluster are reduced by 0.37 eV and 0.15 eV, respectively, compared with the pristine Cu 4 cluster. The calculation results also show the overpotentials for the CO 2 hydrogenation to CH 4 in the order of Cu 4 S < Cu 4 O < Cu 4 Se. In addition, the geometry structures, the electronic properties, and the reaction free energies on the chalcogen doped Cu 4 clusters are also discussed to further reveal the reaction mechanism in the CO 2 electroreduction process. We hope that our present work will enlighten extensive studies on the modified electrode to decrease the limiting potential and provide a reference for the subsequent studies. [ABSTRACT FROM AUTHOR]

With an increase in train speed, the aerodynamic effects caused by the train could escalate, especially for a train running in a tunnel. A number of large transient pressure waves are generated owing to the confined spaces within the tunnel, resulting in possible damage to the vehicle structure and the facilities in the tunnel. Therefore, it is necessary to study the aerodynamic performance of a train running in a tunnel. A scaled moving model test system was constructed to facilitate the simulation of the aerodynamic effects caused by a train running in a tunnel. In this study, the influence of grid density, calculation time step, and turbulence model on the pressure caused by the train entering the tunnel was analyzed, which is helpful for choosing suitable values of the aforementioned parameters to simulate the aerodynamic performance of the train in the tunnel. The impacts of Reynolds number effect on the distribution of the surface pressure and peak of pressure wave along the train, and the pressure waveform were also studied through numerical simulation on three scaled model trains (full scale, 1/8, 1/20, and 1/32 scaled). The findings aid in understanding the relationship between the Reynolds and pressure amplitude, and the results of the scaled test can be applied to a full-scale train. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of oblique tunnel portals on train and tunnel aerodynamics using a 1:20 scale moving model device. Transient pressure and micro-pressure waves were measured using pressure sensors as the train model travelled through various tunnel models at a speed of 350 km/h. The mitigation physical mechanism of oblique tunnel portal on the initial compression wave was explained. Experimental results showed that oblique tunnel portals had obvious mitigation effect on- the pressure gradient and micro-pressure wave induced by the train model passing through the tunnel model. A hat oblique tunnel portal combined with a buffer structure with top holes was particularly effective. [ABSTRACT FROM AUTHOR]

The aerodynamic characteristics of a high-speed train in an atmospheric boundary layer are investigated in a wind tunnel. In addition, different atmospheric boundary layer simulations are performed by changing the turbulence intensity generated by a collection of spires in a wind tunnel. Turbulent flow information, measured with the Cobra probe, is used to describe the atmospheric boundary layer. Furthermore, the effect of velocity on the atmospheric boundary layer is also studied. Both the train’s unsteady aerodynamic force and surface pressure are measured at a Reynolds number of 7.5 × 10 5 , and their mean and standard deviation are used to describe and explain the effect of turbulence and observed trends with varying turbulence intensity. [ABSTRACT FROM AUTHOR]

Wind speed forecasting technology is important in the field of wind power. However, the wind speed signals are always nonlinear and non-stationary so that it is difficult to predict them accurately. Aims at this challenge, a new hybrid approach has been proposed for the wind speed high-accuracy predictions based on the Secondary Decomposition Algorithm (SDA) and the Elman neural networks. The proposed SDA combines the Wavelet Packet Decomposition (WPD) and the Fast Ensemble Empirical Mode Decomposition (FEEMD), which includes twice decomposing processes as: (a) the WPD decomposes the original wind speed into the appropriate components and the detailed components; and (b) the FEEMD further decomposes the WPD generating detailed components into a number of wind speed Intrinsic Mode Functions (IMFs). The experimental results in five real forecasting cases show that: (a) the proposed hybrid WPD-FEEMD-Elman model has satisfactory performance in the multi-step wind speed predictions; and (b) the hybrid WPD-FEEMD-Elman model has improved the forecasting performance of the hybrid WPD-Elman model and the standard Elman neural networks considerably. [ABSTRACT FROM AUTHOR]

Establishing an intuitive link between driving factors of household energy consumption activities and inequalities is important for the understanding of household heterogeneity in energy consumption behaviours. This paper proposes a novel typology framework based on machine learning approaches and data from 3637 Chinese households in 2014 from 85 cities. Activity-based energy consumption was measured, highlighting inequalities across activities, regions and household types. The results showed significant energy consumption disparities between urban/rural and north/south households, especially in cooking, space heating and vehicle activities. By identifying driving factors of energy consumption, a new household typology classified samples into 6 (all), 6 (urban) and 7 (rural) types. Within these types, households with similar demographic structures, lifestyles and energy consumption habits were clustered. Demographic structure, region, and primary energy demand were used as the basis for the typology. The findings demonstrated how household lifestyle differences explained the cause and underlying driving factors of urban-rural energy consumption inequalities and provided suggestions for city-by-city and type-by-type measurements to support effective low-carbon transformation in cities. • Activity-based household energy consumption (HEC) is measured and calibrated. • Household energy consumption inequalities exist in urban/rural and the north/south groups. • A four-step machine-learning approach well classifies households into reasonable clusters. • Activity-based variables are driving factors for HECs in a LASSO model. • Inequality is narrowed in household clusters and type-by-type policies are needed. [ABSTRACT FROM AUTHOR]

This paper aims at investigating the effect of the inflow turbulence on the aerodynamics and the wake instabilities of the wind turbine. The improved delayed detached eddy simulation (IDDES) combined with the overset grid method is performed to model the NREL S826 airfoil wind turbine at design operating condition (λ = 6.0). The mean loads of power coefficient (C P) and thrust coefficient (C T) show good agreement with existing experiments data. The normalized mean velocity U / U r e f profile and normalized turbulent kinetic energy k / U 2 r e f profile within the wake is also consistent with the experiments data, indicating a fairly accurate predictions of the wake turbulence. The detailed analysis of wake vortex structure, mean Reynold's stress distribution and PSD spectrum of turbulent kinetic energy are utilized to explore the effect of incoming turbulence on the wind turbine performance and the mechanism of the wake instability. The incoming turbulence and wind shear may promote the tip vortex instability and accelerate wake recovery, thus more attention should be paid to the design procedure and layout of wind farms. • Effect of inflow turbulence on the aerodynamics performance was studied. • Changes in the wake vortices instability due to inflow turbulence were assessed. • Results showed that incoming turbulence can accelerate wake recovery. • Power spectral density curve shifted, implying a complete turbulence wake state. [ABSTRACT FROM AUTHOR]

Abstract: An argon glow discharge plasma was used for the reduction of carbon-supported Au catalysts at ambient temperature. The plasma-reduced Au/C sample produced 7–8nm Au particles that were highly dispersed on carbon. The surface oxygen species on carbon were increased by plasma treatment. Most interestingly, the metal particles were recessed into the carbon substrate. The stronger anchoring enhanced the stability of the active metal loaded on the support. The Au/C catalysts were tested for selective oxidation of glucose to gluconic acid compared with conventional hydrogen reduced catalysts. A significant improvement in glucose oxidation was achieved by the plasma-reduced sample. [Copyright &y& Elsevier]

Abstract: For nonsmooth convex optimization, Robert Mifflin and Claudia Sagastizábal introduce a -space decomposition algorithm in Mifflin and Sagastizábal (2005) . An attractive property of this algorithm is that if a primal–dual track exists, this algorithm uses a bundle subroutine. With the inclusion of a simple line search, it is proved to be globally and superlinearly convergent. However, a drawback is that it needs the exact subgradients of the objective function, which is expensive to compute. In this paper an approximate decomposition algorithm based on proximal bundle-type method is introduced that is capable to deal with approximate subgradients. It is shown that the sequence of iterates generated by the resulting algorithm converges to the optimal solutions of the problem. Numerical tests emphasize the theoretical findings. [Copyright &y& Elsevier]