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The corrosion behaviour and mechanism of CoCrNi medium-entropy alloy (MEA) imposed by alternating current (AC) in HCO3−/CO32− solution with various pH were systematically investigated via a series of corrosion tests. The results showed that with the augment of pH value, the polarisation resistance of the MEA decreased significantly, Ep shifted negatively, and ipI value increased, as well as corrosion rate was enhanced, revealing that the corrosion resistance was weakened. As solution pH increased, the formation of secondary passivation zone became easier, which may be attributed to the reaction conversion process of Cr(III) to Cr(VI) species. Moreover, the increase in pH led to an increase in defect density and a thinning of passivation film, facilitating the corrosion of the MEA. AC interference accelerated the ion exchange process and promoted the formation possibility of stable pitting. Higher iAC and pH inhibited the repassivation of metastable pitting, and increased the pitting susceptibility. Highlights The effect of pH on the corrosion behaviour of CoCrNi MEA with imposed AC was clarified. High pH and iAC accelerated the nucleation and growth of metastable pits. With increased pH and iAC, the stability and protective ability of passive film were weakened. The secondary passivation of the MEA was mainly due to the conversion of Cr(III) to Cr(VI) species. [ABSTRACT FROM AUTHOR]

The Xiaomojiu landslide is a typical high-elevation, long-runout landslide located in the Jinsha River Corridor. In this study, sequential InSAR time-series estimation was used to calculate the line of sight (LOS) surface displacements with descending and ascending Sentinel-1 images, and it turned out that the cumulative LOS surface displacement of the landslide was up to −78.4 mm during the period from October 2017 to April 2021 with the maximum LOS surface displacement rate of −38.5 mm/year. The landslide body could be divided into five zones (A, B1, B2, B3, and C) according to its topographical characteristics together with the LOS surface displacement time series. Combining engineering geological characteristics, LOS cumulative surface displacements with site investigation suggest that the Xiaomojiu landslide is likely to be a precipitation-triggered ancient traction rock landslide at the accelerated deformation stage. A dynamic simulation of the Xiaomojiu landslide with the PFC3D software shows that it could take approximately 65 s for the Xiaomojiu landslide from start-up to acceleration to deceleration to build-up of a barrier lake, followed by a simulation from the barrier lake to outburst floods with the HEC-RAS software indicating that the maximum depth of the outburst floods could be 13.5 m (15%), 24.6 m (25%), 42.1 m (50%), and 50.3 m (75%) along Qinghai-Tibet Plateau Transportation Corridor (QTPTC). It is believed that the results of this study provide a reference for landslide prevention along the QTPTC and the Jinsha River. [ABSTRACT FROM AUTHOR]

Water scarcity, the intensification of agricultural nonpoint pollution, and continuous deterioration of the ecosystem are serious problems in arid areas. Optimal allocation of water resources is the key way to achieve sustainable and efficient development of irrigated agriculture. An integrated multiobjective optimization model considering water-balance processes was developed under shallow groundwater environments to enhance comprehensive objectives and obtain optimal irrigation solutions. A simulation module of the physical processes of water movement among crop root zones, soil water, and groundwater aquifers, and a multiobjective optimization module of irrigation water allocation were incorporated into a general framework. It has the following advantages in terms of (1) illustrating variations of agricultural hydrological parameters (e.g., soil water content, groundwater depth, groundwater-based evaporation, and so on) in water movement processes; (2) obtaining a set of noninferior decision-making solutions through a modified nondominated sorting genetic algorithm (NSGA-II), which can maximize the interests for multiple parties; and (3) generating optimal solutions of irrigation water allocation and alleviating water scarcity, improving irrigation water productivity, and reducing negative environmental effects. To demonstrate its applicability, it was applied to optimize irrigation water allocation in the Jiefangzha Irrigation Subarea (JIS), China. It was firstly split into 44 irrigation subsystems, and each subsystem was assumed to be a homogeneous unit in meteorology, soil texture, and groundwater. Under the water competition between subsystems and rigid constraints of water availability, optimized results enhanced net economic benefits by 14.7%, saved 7.74% of irrigation water amount, and improved irrigation water productivity by 13% compared with status quo. Meanwhile, it can reduce graywater footprint of grain production by 58% compared with the average level of Hetao Irrigation District, China. [ABSTRACT FROM AUTHOR]

Multi-view semi-supervised classification is inherently a challenging task in multi-view learning due to the lack of label information. Existing methods generally suffer from insufficient data fusion, expensive computation cost in the solution procedure and fail in tackling unseen samples directly, intensively limiting their applicability and efficiency in real scenarios. To address these issues, we propose an adaptive collaborative fusion method, seeking for an appropriate representation and fusion for multi-view data. The main advantage of the proposed method is that it simultaneously fuses both multiple feature projections and similarity graphs to learn a joint projection subspace as well as a unified similarity graph that fully preserve the correlation and distinction among views. Meanwhile, our method can coalesce different views in an adaptive-weighting manner, making the learned subspace more discriminative and facilitating label propagation on the fused graph. Furthermore, an acceleration strategy has been designed to reduce the computational complexity, thereby making the proposed method scalable to relatively large-scale data. Finally, an alternating optimization has been adopted to solve the formulated objective function. Extensive experiments on synthetic and real-world datasets are conducted to demonstrate the effectiveness and superiority of our proposed method. • Propose a collaborative fusion method for multi-view semi-supervised learning. • Adaptively fuse different views to learn a joint projection and a unified graph. • The proposed method can efficiently deal with large-scale multi-view data. • Experiments on various datasets validate the method effectiveness and efficiency. [ABSTRACT FROM AUTHOR]

The corrosion behavior and mechanism of CoCrFeNi HEA under AC application were systematically studied in 3.5 wt.% NaCl solution containing different concentrations of NaHSO3. The results showed that the existence of HSO3− increased the defect density within the passivation film on the surface of the HEA. With the increase of HSO3− concentration, the passivation zone became narrow, Ep shifted negatively, and ip increased, which indicated that the corrosion resistance of the HEA was weakened. When the HSO3− concentration increased to 0.1 M, a clear transition zone appeared, indicating that the increase in concentration reduced the passivity of the HEA, and its corrosion behavior changed from the typical passivation characteristic to the activation state with increasing iAC. The imposed AC promoted the nucleation of metastable pitting, which was indicated by a remarkable increase in the average pitting number density (Navg) from 5 to 17 mm−2 with the enhancement of iAC. [ABSTRACT FROM AUTHOR]

This study compares the accuracy and effectiveness of our novel 3D-printed titanium cutting guides with intraoperative surgical navigation for performing intraoral condylectomy in patients with mandibular condylar osteochondroma (OC). A total of 21 patients with mandibular condylar OC underwent intraoral condylectomy with either 3D-printed cutting guides (cutting guide group) or with surgical navigation (navigation group). The condylectomy accuracy in the cutting guide group and navigation group was determined by analyzing the three-dimensional (3D) discrepancies between the postoperative computed tomography (CT) images and the preoperative virtual surgical plan (VSP). Moreover, the improvement of the mandibular symmetry in both groups was determined by evaluating the chin deviation, chin rotation and mandibular asymmetry index (AI). The superimposition of the condylar osteotomy area showed that the postoperative results were very close to the VSP in both groups. The mean 3D deviation and maximum 3D deviation between the planned condylectomy and the actual result were 1.20 ± 0.60 mm and 2.36 ± 0.51 mm in the cutting guide group, and 1.33 ± 0.76 mm and 4.27 ± 1.99 mm in the navigation group. Moreover, the facial symmetry was greatly improved in both groups, indicated by significantly decreased chin deviation, chin rotation and AI. In conclusion, our results show that both 3D-printed cutting-guide-assisted and surgical-navigation-assisted methods of intraoral condylectomy have high accuracy and efficiency, while using a cutting guide can generate a relatively higher surgical accuracy. Moreover, our cutting guides exhibit user-friendly features and simplicity, which represents a promising prospect in everyday clinical practice. [ABSTRACT FROM AUTHOR]

Background: The research aimed to evaluate the optimal Single-Photon Emission Computed Tomography (SPECT) cut-off value in differentiating condylar growth activeness, to observe 3-dimensional (3D) mandibular growth pattern, and to explore the potential correlation between 3D measurement parameters and SPECT uptake ratios in Chinese unilateral condylar hyperplasia (UCH) patients. Methods: Data of fifty-four Chinese UCH patients were analyzed retrospectively. All patients underwent SPECT within 1 month before or after the first CT examination (CT1); and received a second CT examination at least 12 months later (CT2). Data from CT scans were analyzed by comparing bilateral differences between CT1 and CT2. The sensitivity and specificity of SPECT were calculated by the receiver operating characteristic (ROC) curve. Pearson's correlation analysis was performed to investigate whether the mandibular growth was correlated with SPECT value. Results: SPECT had a sensitivity of 68.00% and a specificity of 72.41%, with an area under the ROC curve being 0.709. The optimal SPECT cut-off value for evaluating condylar activity has been determined to be 13%. In patients with an active growing condyle, there was a significant increase in Co-Gn and Co-Go, but not in Go-Gn, Go-MF, or MF-Gn. Pearson's correlation analysis revealed no correlation between 3D measurement parameters and differences in relative condylar uptake ratios. Conclusion: SPECT showed good diagnostic performance in UCH with the cut-off value of 13%. For those with an active growing condyle, the mandible grows diagonally and vertically, while the relative condylar uptake ratio was not directly related to mandibular growth. [ABSTRACT FROM AUTHOR]

[Display omitted] • A one-step leaching process for spent LiCoO 2 based on the mechanochemical method. • The new application of grape skins promotes the leaching of spent LiCoO 2. • Effect of mechanical activation on the interfacial reaction of spent LiCoO 2. • The mechanism of mechanochemical leaching was analyzed by BET, PSD, XRD, and XPS. A one-step system based on mechanochemical activation and the use of grape skins (GS) was proposed to recover metals from lithium-ion batteries (LIBs) cathode waste. The effects of the ball-milling (BM) speed, BM time, and quantity of added GS on the metal leaching rate were explored. The spent lithium cobalt oxide (LCO) and its leaching residue before and after mechanochemistry were characterized by SEM, BET, PSD, XRD, FT-IR, and XPS analysis. Our study shows that mechanochemistry promotes the leaching efficiency of metals from LIBs battery cathode waste by changing the cathode material properties (that is, reducing the LCO particle size (12.126 μm ∼ 0.0928 μm), increasing the specific surface area (0.123 m2/g ∼ 15.957 m2/g), enhancing the hydrophilicity and surface free energy (57.44 mN/m2 ∼ 66.18 mN/m2), promoting the generation of mesoporous structures, refining grains, disrupting the crystal structure, and increasing the microscopic strain, while deflecting the binding energy of the metal ions). A green, efficient and environmentally friendly process for the harmless and resource-friendly treatment of spent LIBs has been developed in this study. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of equiatomic CoCrFeNi and CoCrFeNiMn high entropy alloys manufactured by the vacuum arc melting were studied in 3.5 wt-% NaCl solution. And the reasons for the differences in corrosion resistance were investigated in terms of microstructure, electrochemical behaviour and oxide film. The results show that the two alloys exhibit different corrosion characteristics, with CoCrFeNi alloy displaying typical passivation characteristics and CoCrFeNiMn alloy exhibiting activation behaviour. The CoCrFeNi HEA with compact and protective passive film has lower corrosion current density, larger film resistance and polarisation resistance, meaning a lower corrosion rate and superior corrosion resistance compared with those of CoCrFeNiMn alloy. Moreover, CoCrFeNiMn alloy forms a discontinuous and loose corrosion product film with higher Mn content and lower contents of Cr, Fe and Co compared to the matrix, which decreases its protection performance. The addition of Mn changes the electrochemical behaviour, and higher Mn oxides/hydroxides within oxide film are unfavourable to forming a stable passive film. [ABSTRACT FROM AUTHOR]

Submarine volcanism is widely developed in the South China Sea (SCS). However, the characteristics, distribution, and genesis of submarine volcanoes in the southern margin of the SCS remain obscure. In this study, we analyzed the characteristics of submarine volcanoes and identified a total of 43 submarine volcanoes in the southern margin of the SCS, based on a newly acquired 310-km seismic reflection profile, along with previous 45 multi-channel seismic (MCS) profiles, petrological results from volcanic rocks sampled by dredging and drilling, nearby ocean bottom seismometer (OBS) wide-angle seismic profiles, and gravity and magnetic data. The study ascertains that most of these volcanoes are located in fault-block belts and graben-horst zones with strong crustal stretching and thinning. These volcanoes exhibit positive high-amplitude external seismic reflections, weak and chaotic internal seismic reflections, and are accompanied by local deformation of the surrounding sedimentary strata. Meanwhile, they have higher positive gravity anomalies and higher magnetic anomalies than the background strata. The petrological dating results show that volcanic ages are primarily in the Pliocene-Pleistocene, with geochemical characteristics indicating dominance of oceanic island basalt (OIB) -type alkali-basalts. Extensional faults have obviously spatial correspondence with post-spreading volcanism, suggesting these faults may provide conduits for submarine volcanism. The high-velocity bodies (HVBs) in the lower crust and magma underplating exist in the southern SCS, which could provide a clue of genesis for submarine volcanism. The inference is that the intensity of post-spreading volcanism in the southern margin might be affected by stretching faults, crustal thinning and magma underplating. [ABSTRACT FROM AUTHOR]

A timely and accurate spatial inventory of flowering characteristics benefits both the floral phenology monitoring in ecology and various crop management activities in agricultural systems. Recent advancement has proven the superiority of computer vision in flower classification at image level. Yet progress in the flowering intensity estimation at tree level is much less and still far from satisfactory. To tackle this problem, a novel approach was designed for the use of single raw aerial images to quantify flower intensity. With pre-prepared dataset, flower-associated pixels were extracted for individual trees using a pixel-based classification method, the color thresholding. Next, three flowering indices retrieved from unmanned aerial vehicle (UAV) were evaluated, the index percentage (IPG), index pixel (IP), and index area (IA). Finally, linear correlation of the flowering indices to flower cluster number and expert-assessed floridity recorded in the field were calculated. Results indicated that IPG yielded the highest correlation to flower cluster (R2 = 0.93, RMSE = 8) and floridity estimation (R2 = 0.78, RMSE = 0.9). A UAV-based floridity scoring method was also designed for automatic estimation tasks in practice, and a comparable and even better performance to the expert-based approach was demonstrated. Furthermore, effects of vertical (nadir) and horizontal (angular) overlapping of flower clusters within the canopy were evaluated, showing excellent potential to improve the estimation accuracy. [ABSTRACT FROM AUTHOR]

The Jinsha River flows through one of the most geologically complex regions in western China with extremely high altitudes and capricious climates. Frequent landslides (e.g., the Baige landslides on 11 October and 3 November 2018) occurred along its stretch which posed severe damage to bridges, dams, and roads, and put the safety of local residents at risk. Systematic and comprehensive landslide detection has been rarely carried out in the Jinsha River corridor because it is a wide and hard-to-reach region. With 30 years of development, InSAR has become an effective way to map ground motion, which in turn makes it feasible to detect active landslides over wide regions. However, several challenges remain in applying InSAR in the Jinsha River corridor, such as low coherence due to dense vegetation and/or large gradient surface movements, and atmospheric effects due to the spatio-temporal variations of the atmosphere (especially the part due to tropospheric water vapor). In this paper, we propose a framework to overcome the limitations of conventional InSAR through the integration of GACOS-assisted InSAR, advanced SBAS InSAR, and SAR pixel offset tracking techniques. This integrated framework enables us to detect active landslides under complex topographic and climate conditions. Our results show that the detected active landslides are largely controlled by active faults, most of them are found at elevations of 2500–4000 m, their slopes fall between 25 and 45 ∘ facing southwest and northwest, and 83.3% of the active landslides have a NDVI value of less than 0.3. Furthermore, precipitation is one critical triggering factor of active landslides, evidenced by the high temporal correlation between average precipitation and surface displacement time series. [ABSTRACT FROM AUTHOR]

Key message: Seed priming with pig blood protein hydrolysate improves tomato seed germination and seedling growth via regulation of reserve mobilization, osmotic adjustment, and antioxidant mechanism under drought conditions. Protein hydrolysates obtained from agro-industrial byproducts are widely recognized because of their positive roles in regulating plant responses to environmental stresses. However, little is known regarding the roles of animal protein hydrolysates in mediating seed drought tolerance and its underlying mechanisms. This study investigated the potential effects of seed priming on tomato seed germination and seedling growth under PEG-induced drought stress using protein hydrolysates derived from pig blood (PP). PP priming effectively alleviated the drought-induced reduction in seed germination traits, resulting in improved tomato seedling growth. PP priming enhanced the gene expressions and activities of amylase and sucrose synthase and soluble sugar, soluble protein, and free amino acid levels, thereby promoting reserve mobilization in seeds. PP priming also reduced osmotic toxicity through increased accumulations of proline, soluble protein, and soluble sugar. Drought stress substantially enhanced reactive oxygen species production and the subsequent increases in malondialdehyde levels and Evans blue solution uptake, which were substantially alleviated after PP priming via the improved activities of enzymatic and non-enzymatic antioxidants. Moreover, the increased DPPH free radical scavenging capacity and ferric reducing antioxidant power indicated that PP-treated tomato seedings had high antioxidant activities under drought stress. Therefore, PP priming is a novel, promising, and practicable method for improving tomato seed germination and seedling growth under drought stress. [ABSTRACT FROM AUTHOR]

Carbonaceous aerosols (CA) are crucial components in the atmospheric PM 2.5 and derived from diverse sources. One of the major sources for CA is from the incomplete combustion of bituminous coal that has been prevailingly used by household stoves in rural areas for heating during winter. To efficiently eliminate the CA emission, a new household stove (NHS) was developed based on a novel combustion technology and CA emissions from the NHS and a traditional household stove (THS) were comparably investigated under the actual stove operation conditions in a farmer's house. Compared with the THS, the emission factors of organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC) from the NHS were reduced by 96%±1%, 98%±1%, and 91%±1% under the flaming process and 95%±1%, 96%±2%, and 83%±4% under the smoldering process, respectively. Additionally, the mass absorption efficiency of WSOC from the NHS reduced by 3 folds and the radiative forcing by WSOC relative to EC shrank remarkably by a factor of 3-8. Based on the reduction of emissions and light absorption of WSOC, the promotion of the NHS offers a possible solution to achieve the clean combustion of residential solid fuel. [Display omitted] [ABSTRACT FROM AUTHOR]

Chemical and mechanical thinning processes have long been used in stone and pome fruit production. During the thinning of apple flowers, growers use chemicals to regulate the tree load. Hand thinning is applied after the June drop to prune trees with excess crop load. The process of thinning can be unpredictable especially in biennial bearing cultivars. Thus, incentives to optimise chemical usage and to reduce expensive manual labour is ever increasing. Ground based machine vision systems have grown in popularity in orchard management due to the level of detail as well as plant coverage they can inspect with. Additionally, unmanned aerial vehicles (UAV) -based remote sensing technology is becoming a popular non-invasive quality inspection solution. This work proposes a framework for combining UAV and ground based RGB image data to detect flowering intensity in a Dutch Elstar apple orchard. The framework, based on point cloud reconstruction, presents automatic point cloud handling techniques as well as automated unsupervised flowering intensity estimation methods. Two linear regression models based on unsupervised machine learning methods were trained and validated from the framework that estimate flowering intensity in the orchard with both models having R2 > 0.65, RRMSE < 20% and p-stat < 0.005 for the correlation between the image derived flower index and the flower cluster number counted in field. The proposed methods provide a novel strategy for guiding flower thinning using simple RGB images and location data only. Moreover, the proposed methods also reveal the flexibility of intra-tree inspection by checking its sub-volumes. • Automatic flower cluster estimation at the tree level with a R2 = 0.7, RMSE < 20. • Ground and aerial point clouds have better performance when combined. • Novel strategy developed for guiding flower thinning in orchard management. • Dataset with aerial and ground images, and field sampling data released. [ABSTRACT FROM AUTHOR]

The effect of different annealing temperatures on the corrosion behavior of CoCrNi medium entropy alloy (MEA) was investigated in an alkaline soil simulation solution. The results show the corrosion resistance of the MEA gradually increases with increasing annealing temperature. The corrosion behavior of the MEA is correlated with grain size, oxide inclusions, and surface passive film. With an increasing grain size, the proportion of grain boundaries decreases, which improves its corrosion resistance. The micro‐galvanic corrosion cell exists between the oxide and its surrounding matrix, which promotes the occurrence of pitting corrosion. As the annealing temperature increases, the film formed on the MEA surface becomes more complete and dense, greatly increasing the corrosion resistance of the MEA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-synthesized Deep-Eutectic Solvents System leaches > 99% silver from PVs. • The intermolecular hydrogen bond forming is conductive to silver leaching. • The metal complex generation mechanisms were proposed. • The reaction system could be cyclically utilized. Traditional acid-base leching technology is the primary technology to recycle silver from crystal silicon solar panels, which is fussy and often employs poisonous/harmful chemicals. In the present study, silver was easily recycled from photovoltaic panels in self-synthesized. Deep-Eutectic Solvents System (DESs) without pretreatments and the reaction system could be cyclically utilized. The leaching and precipitation rate can reach 99% under the optimized conditions. In addition, the kinetic results showed that the leaching of silver followed the classical shrinkage core model, in which chemical reaction was the rate-controlling step and the apparent activation energy for leaching process is 172.36 kJ·mol−1. In the recycling process, Cu2+ acted as the oxidant, and the redox potential of Cu2+ in the DES system is much higher than that in aqueous system. Besides, the HNMR and FTIR analysis indicate that the intermolecular hydrogen bond formed in the DES mixed system, which would raise the melting and boiling point of the mixed system, and would be conducive to the following silver leaching process. Furthermore, the metal complex generation mechanisms were proposed in the present study, and urea plays not only an aprotic solvent which cannot solvate Cl-, but also the ligand which can complex with the metals as well as Cl- which can reduce the redox potentials and shift the equilibrium to the silver leaching side. In summary, this study can provide theoretical foundation and practical experience for recycling precious metals from waste crystal silicon solar panels environmentally efficient and cost-effective. [ABSTRACT FROM AUTHOR]

Broad learning system (BLS) demonstrates a novel structure of neural networks based on random vector functional link network (RVFL), which has a faster modeling speed, better generalization ability, higher regression accuracy for solving regression tasks. To improve the feature representation capacity of BLS and guarantee the training efficiency, a novel ensemble deep model based on broad learning system is proposed, named as EDBLS. Unlike other deep or ensemble models of BLS, the results of EDBLS can be calculated by training the model only once. Meanwhile, the performance of BLS mainly depends on its structure, it is the same as EDBLS, we need to select network parameters for different real-world problems. As the lower efficiency of grid search, it is no longer suitable for EDBLS with more parameters. Therefore, coot optimization algorithm (COOT) is applied to determine the network structure of EDBLS for regression problems, it is important to note that the COOT is only a tool for determining the structure of EDBLS. Finally, the experimental results on MNIST, NORB and some regression benchmark datasets show that EDBLS has a better classification and regression performance, COOT is beneficial to select the network parameters of EDBLS for regression. [ABSTRACT FROM AUTHOR]

Medical hyperspectral imaging provides new possibilities for non-invasive detection and characterization of diseases, and the processing of images can be accelerated and rationalized by using deep learning technology to classify pixels as one tissue or another, or as lesion or healthy tissue. However, most current methods for intelligently identifying pixels are not robust to large variations in pixel intensity within an image, particularly local learning approaches that rely on pixel or patch input. In this paper, we propose a network being able to learn to classify all pixels on an image by training with only a small number of manually labeled pixels in the same image. The network contains a hard band attention module (HBAM) to eliminate noisy bands and a dual-kernel spatial–spectral fusion attention module (DK-SSFAM) which uses two convolution kernels to weight spatial and spectral features and integrates them accordingly. We demonstrate that our proposed weakly supervised single-image global learning (SiGL) network classifies pixels in hyperspectral images of human brain in vivo better than traditional deep learning methods, suggesting potential for the clinic. [ABSTRACT FROM AUTHOR]

The airship exhibits great potential as an aerostat; however, the issue of connection in envelope composites, which serve as the primary structural material, significantly hampers its progress. Here, for the first time, we investigate the potential application of adhesive bonding techniques for connecting envelope composites. Several adhesively bonded joints based on Vectran-based envelope composite are prepared using the hot-pressing method. The obtained adhesively bonded joints exhibit a failure strength of 3.57 MPa, which is more than twice that of the welded envelope composite joints. Then, the mechanical response behaviors of adhesively bonded joints are investigated using mechanical testing, failure morphologies analysis, infrared thermal imaging, digital image correlation technique, and numerical simulation. Experimental results show that the structural parameters (adhesive content, bonding area, and the gauge length of the tested strips) of adhesively bonded joints have a significant impact on mechanical performance. Simulation results show that the stiffness mismatch of the component materials has a negative effect on the failure strength of adhesively bonded joints, which explains why the failure occurs at the fabric interface rather than the adhesive region. [ABSTRACT FROM AUTHOR]

Advances in sensor miniaturization are increasing the global popularity of unmanned aerial vehicle (UAV)-based remote sensing applications in many domains of agriculture. Fruit orchards (the source of the fruit industry chain) require site-specific or even individual-tree-specific management throughout the growing season—from flowering, fruitlet development, ripening, and harvest—to tree dormancy. The recent increase in research on deploying UAV in orchard management has yielded new insights but challenges relating to determining the optimal approach (e.g., image-processing methods) are hampering widespread adoption, largely because there is no standard workflow for the application of UAVs in orchard management. This paper provides a comprehensive literature review focused on UAV-based orchard management: the survey includes achievements to date and shortcomings to be addressed. Sensing system architecture focusing on UAVs and sensors is summarized. Then up-to-date applications supported by UAVs in orchard management are described, focusing on the diversity of data-processing techniques, including monitoring efficiency and accuracy. With the goal of identifying the gaps and examining the opportunities for UAV-based orchard management, this study also discusses the performance of emerging technologies and compare similar research providing technical and comprehensive support for the further exploitation of UAVs and a revolution in orchard management. [ABSTRACT FROM AUTHOR]

An AIE-active fluorescent probe, MHTS, with good sensitivity and selectivity for the detection of Cu2+ was synthesized from myrtenal. The fluorescence intensity of MHTS at 542 nm indicated a good linear relationship with the concentration of Cu2+ in the range of 0–20 μM, and the detection limit was 1.25 × 10−7 M, which was far lower than the national standard of Cu2+ in drinking water. The interference experiment showed that other metal ions show no interference on the detection of Cu2+. The fluorescence of MHTS changed from yellow to colorless under a 365 nm UV light. The detection of Cu2+ was effective in the pH range of 3–8. Therefore, it can be used for the detection of Cu2+ in fresh vegetables and zebrafish. [ABSTRACT FROM AUTHOR]

It is unclear whether the South China blocks have an affinity with continental Gondwana due to a lack of direct Pan‐African magmatic and metamorphic features. In this study, we conducted U‐Pb geochronological and Lu‐Hf isotopic analyses for detrital zircons from a sandstone of the Chang'an Formation of the Nanhua Group in the Longsheng region of northern Guangxi, with the aim of constraining the timing of sedimentation and information as to its source, as well as seeking evidence for Pan‐African events in the South China blocks. The results show that the ages of detrital zircons peaked at 654.7 ± 6.2 Ma, 773.2 ± 4.1 Ma and 821.9 ± 6.5 Ma, with some at 920–870 Ma; the youngest age indicates the existence of the Pan‐African thermal event. The ∊Hf(t) and TDM2 values demonstrate that the study area has experienced three stages of crustal growth at 3.0–2.4 Ga, 2.1–1.5 Ga and 1.3–0.9 Ga. With intensively distributed Neoproterozoic mafic‐ultramafic and granitic plutons emplaced at 830–810 Ma along the southwestern section of the Jiangnan Orogenic Belt and positive ∊Hf(t) values from a large group of zircon grains, it is proposed that the sediments of the Chang'an Formation (of Nanhua Group) were largely sourced from the southeastern margin of the Yangtze block. Comparison with the zircon age spectra of the Cathaysian block shows that about 79% of the Pan‐African aged detrital zircon grains that have TDM2 = 1352–1031 Ma and ∊Hf(t) = 3.68–8.79, were sourced from the recycled Grenvillian crust of the Cathaysian block, suggesting that the Cathaysian block had a close connection with Gondwana. [ABSTRACT FROM AUTHOR]

[Display omitted] • Choline Chloride–ethylene glycol system leaches > 99 % gold from FPCBs. • Formation of hydrogen bonds in the DES system facilitates the leaching of gold. • Proposed mechanism for the production of metal complexes. • The reaction system could be cyclically utilized. The traditional hydrometallurgy technology has been widely used to recover precious metals from electronic waste. However, such aqueous recycling systems often employ toxic/harsh chemicals, which may cause serious environmental problems. Herein, an efficient and environment-friendly method using a deep eutectic solvent (DES) mixed system of choline chloride–ethylene glycol–CuCl 2 ·2H 2 O is developed for gold (Au) recovery from flexible printed circuit boards (FPCBs). The Au leaching and precipitation efficiency can reach approximately 100 % and 95.3 %, respectively, under optimized conditions. Kinetic results show that the Au leaching process follows a nucleation model, which is controlled by chemical surface reactions with an apparent activation energy of 80.29 kJ/mol. The present recycling system has a much higher selectivity for Au than for other base metals; the two-step recovery rate of Au can reach over 95 %, whereas those of copper and nickel are < 2 %. Hydrogen nuclear magnetic resonance spectroscopy (HNMR) and density functional theory (DFT) analyses confirm the formation of intermolecular hydrogen bonds in the DES mixed system, which increase the system melting and boiling points and facilitate the Au leaching process. The Au leaching system can be reused for several times, with the leaching efficiency remaining > 97 % after five cycles. Moreover, ethylene glycol (EG) and choline chloride (ChCl) act as aprotic solvents as well as coordinate with metals, decreasing the redox potential to shift the equilibrium to the leaching side. Overall, this research provides a theoretical and a practical basis for the recovery of metals from FPCBs. [ABSTRACT FROM AUTHOR]

Peroxyacetyl nitrate (PAN) is an important photochemical pollutant in the troposphere, whereas long-term measurements are scarce in rural areas in North China Plain (NCP), resulting in unclear seasonal variations and sources of PAN in rural NCP. In this study, we conducted a 1-year observation of PAN during 2021-2022 at the rural NCP site. The average concentrations of PAN were 1.10, 0.75, 0.65, and 0.88 ppbv in spring, summer, autumn, and winter, respectively, with a 1-year average of 0.81 ± 0.60 ppbv. Calculations indicate that the loss of PAN through thermal decomposition in summer accounts for 43.2% of the total formed PAN, which is an important reason for the low concentration of PAN in summer. We speculate that since the correlation between PAN and O 3 in winter is significantly lower than that in other seasons, the observed regional transport of PAN cannot be ignored in winter. Through budget analysis, regional transport accounted for 12.8% and 55.9% of the observed PAN on the spring and winter pollution days, respectively, which showed that regional transport played key roles during the photochemical pollution of the rural NCP in winter. The potential source contribution function revealed that the transported PAN mainly comes from southern Hebei in spring. In winter, the transported PAN was mainly from Langfang, Hengshui, and southern Beijing. Our findings may aid in understanding PAN variations in different seasons in rural areas and highlight the impact of regional transport on the PAN budget. [ABSTRACT FROM AUTHOR]

• An automated band selection framework for band clustering, outlier noisy band removal, and intercluster ranking was proposed based on the CCE principle. • Data gravitation was defined to simulate the interrelationships between bands. Based on it, the most representative band is selected from each cluster to ensure sufficient information and internal correlations of the selected band. To the best of our knowledge, this is the first time that data gravitation theory has been applied to band selection. • An entropy-containing similarity matrix was constructed, and a weak correlation intracluster band-sorting strategy was developed, which effectively reduces redundancy while ensuring band information. The final ranking was implemented using a customised S-shaped strategy. • Experiments on human brain MHSIs demonstrated that DGWCR achieves superior performance compared to several state-of-the-art band selection methods and deep learning-based methods. Medical hyperspectral images (MHSIs) are used for a contact-free examination of patients without harmful radiation. However, high-dimensionality images contain large amounts of data that are sparsely distributed in a high-dimensional space, which leads to the "curse of dimensionality" (called Hughes' phenomenon) and increases the complexity and cost of data processing and storage. Hence, there is a need for spectral dimensionality reduction before the clinical application of MHSIs. Some dimensionality-reducing strategies have been proposed; however, they distort the data within MHSIs. To compress dimensionality without destroying the original data structure, we propose a method that involves data gravitation and weak correlation-based ranking (DGWCR) for removing bands of noise from MHSIs while clustering signal-containing bands. Band clustering is done by using the connection centre evolution (CCE) algorithm and selecting the most representative bands in each cluster based on the composite force. The bands within the clusters are ranked using the new entropy-containing matrix, and a global ranking of bands is obtained by applying an S-shaped strategy. The source code is available at https://www.github.com/zhangchenglong1116/DGWCR. Upon feeding the reduced-dimensional images into various classifiers, the experimental results demonstrated that the small number of bands selected by the proposed DGWCR consistently achieved higher classification accuracy than the original data. Unlike other reference methods (e.g. the latest deep-learning-based strategies), DGWCR chooses the spectral bands with the least redundancy and greatest discrimination. In this study, we present a method for efficient band selection for MHSIs that alleviates the "curse of dimensionality". Experiments were validated with three MHSIs in the human brain, and they outperformed several other band selection methods, demonstrating the clinical potential of DGWCR. [ABSTRACT FROM AUTHOR]

Based on the molecular dynamics software package CovalentMD 2.0, the fastest molecular dynamics simulation for covalent crystalline silicon with bond‐order potentials has been implemented on the third highest performance supercomputer "Sunway TaihuLight" in the world (before June 2019), and already obtained 16.0 Pflops (1015 floating point operation per second) in double precision for the simulation of crystalline silicon, which is recordly high for rigorous atomistic simulation of covalent materials. The simulations used up to 160,768 64‐core processors, totally nearly 10.3 million cores, to simulate more than 137 billion silicon atoms, where the parallel efficiency is over 80% on the whole machine. The running performance on a single processor reached 15.1% of its theoretical peak at highest. The longitudinal dimension of the simulated system is far beyond the range with scale‐dependent properties, while the lateral dimension significantly exceeds the experimentally measurable range. Our simulation enables virtual experiments on real‐world nanostructured materials and devices for predicting macroscale properties and behaviors from microscale structures directly, bringing about many exciting new possibilities in nanotechnology, information technology, electronics and renewable energies, etc. © 2019 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract REPO 4 (RE = Gd, Nd, La) ceramics with a monazite structure were fabricated by a chemical co-precipitation and calcination method. Hot corrosion tests were carried out in V 2 O 5 +Na 2 SO 4 molten salt at 800 °C, 900 °C and 1000 °C for 2 h and 10 h. The temperature and heat duration had little effect on the type of corrosion products in this study. However, GdPO 4 and REPO 4 (RE = Nd, La) revealed different hot corrosion behavior. Exposed to the molten salt, GdVO 4 and Gd 4 (P 2 O 7) 3 formed as the corrosion products for the GdPO 4 case, while an RE(P,V)O 4 (RE = Nd, La) solid solution was generated for NdPO 4 and LaPO 4 cases. The formation of the solid solution had less damage to the original microstructure, which benefited the hot corrosion resistance of the ceramics. From the crystallographic characteristics of rare earth phosphates/vanadates and a thermodynamics perspective, the hot corrosion mechanisms of REPO 4 (RE = Gd, Nd, La) are discussed. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that beta 2-microglobulin (B2M) could predict all-cause mortality and cardiovascular mortality in various groups of people. However, the relationship between B2M and severity of coronary stenosis in patients with acute coronary syndrome has not been established.Methods: We enrolled 872 consecutive patients admitted with acute coronary syndrome in our study. All participants underwent coronary angiography examination or stent implantation after admission. The severity of coronary stenosis was assessed by Gensini score and the presentation of triple-vessel disease. B2M and other biochemical parameters were measured. All subjects were divided into quartiles of B2M. Multivariate linear regression and logistic regression were applied in the analysis.Results: Gensini score and the prevalence of triple-vessel disease were elevated in accordance with increasing B2M quartiles (p=0.002 and p<0.001, respectively). Multivariate regression showed diabetes (p=0.031), high-sensitivity C-reactive protein (hs-CRP, p=0.043) and B2M (p=0.006) were positively correlated with Gensini score. Logistic regression analysis revealed that the crude and fully adjusted odds ratios of triple-vessel disease were 2.34 (95% CI: 1.58-3.46) and 1.97 (95% CI: 1.14-3.40) in the fourth quartile of B2M compared with the first quartile, respectively. However, no interactive relationships were found in subgroup analysis by estimated glomerular filtration rate or hs-CRP in the above associations, neither in the distribution of Gensini score (p for interaction>0.05 for both).Conclusion: Our data indicated that B2M was an independent risk factor of coronary stenosis in patients with acute coronary syndrome. [ABSTRACT FROM AUTHOR]

Abstract This study presents an inexact joint-probabilistic double-sided stochastic chance-constrained programming (IJDSCCP) model for sustainable water resources planning and pollution control in water quality management systems under uncertainty. Techniques of interval parameter programming (IPP), joint-probabilistic programming (JPP) and double-sided stochastic chance-constrained programming (DSCCP) are incorporated into a modeling framework. The IJDSCCP can not only address uncertainties presented as interval parameters and double-sided randomness (i.e. both left-hand and right-hand sides) that are characterized as normal distributions, but also examine the reliability level of satisfying the entire system constraints. It further improves upon conventional stochastic chance-constrained programming for handing random uncertainties in the left-hand and right-hand sides of constraints. Moreover, a non-equivalent but sufficient linearization form of the IJDSCCP is presented to solve such a problem. Then, the model is applied to a representative case for water resources planning and pollution control. The results including water resources planning solutions, pollution control plans and system benefits under the combinations of different joint and individual probability levels will be obtained. The solutions are expressed as combinations of deterministic, interval and distributional information, which can facilitate analysis of different forms of uncertainties. After investigating and comparing the variations of results, it is found that an increasing joint probability level can lead to higher system benefits, i.e., [13,841.68, 21,801.81] × 106 Yuan (p = 0.01, p 1 = 0.0033, p 2 = 0.0033 and p 3 = 0.0033), [14,150.26, 22,260.06] × 106 Yuan (p = 0.05, p 1 = 0.0166, p 2 = 0.0166 and p 3 = 0.0166) and [14,280.55, 22,415.52] × 106 Yuan (p = 0.10, p 1 = 0.033, p 2 = 0.033 and p 3 = 0.033). A set of decreased individual probability levels gives rise to the maximum system benefits at the same joint probability level. Furthermore, the results of the IJDSCCP are compared with a general interval-based optimization framework as well. Therefore, the results from the IJDSCCP are valuable for assisting managers in generating and identifying decision alternatives under different scenarios. Graphical abstract Unlabelled Image Highlights • An inexact joint-probabilistic double-sided stochastic chance-constrained programming model is developed. • A non-equivalent but sufficient linearization form of the developed model is presented. • An increasing joint probability level leads to higher system benefits. • A set of decreased individual probability levels results in the maximum system benefits at the same joint probability level. [ABSTRACT FROM AUTHOR]

Abstract The formation of secondary organic aerosol (SOA) from isoprene photooxidation was investigated to reveal the influence of OH concentration on SOA formation through varying the concentrations of isoprene and H 2 O 2 in a smog chamber. The results indicated that the higher the OH concentration was, the less the isoprene consumed for the detectable SOA mass concentration, for example, the lowest isoprene consumption for the detectable SOA was about 14.4 ppb under the OH concentration of about 1.65 × 107 molecules cm−3, whereas tens ppb of isoprene consumption were needed under the OH concentrations <1.0 × 107 molecules cm−3, and even no detectable SOA was observed with isoprene consumption of 75.1 ppb under OH concentration of 7.2 × 105 molecules cm−3. SOA yield was also found to increase with increasing OH concentration for a given aerosol loading (M 0) at atmospherically relevant conditions, confirming that OH concentration played important role in SOA formation from isoprene photooxidation. The maximal SOA yields (5.8–42.8%) obtained by this study were a factor of 1.5–3.1 greater than those reported by previous study for the almost the same initial reactant concentrations of isoprene and H 2 O 2 , and the difference was mainly ascribed to the higher OH concentrations in the reaction systems of this study than those of previous study. The OH concentrations adopted in this study closed to those in the real atmosphere around noontime, and hence the SOA yield obtained from the isoprene photooxidation might be representative. Graphical abstract Unlabelled Image Highlights • SOA could be detected under less isoprene consumption with increasing OH concentration. • SOA yield under atmospheric relevant conditions was greater than those of previous studies. • OH concentration played important role in SOA formation from isoprene photooxidation. [ABSTRACT FROM AUTHOR]

Abstract This study presents an inexact robust two-stage mixed-integer linear programming (IRTMLP) approach for crop area planning under uncertainty. The approach is developed by incorporating the techniques of interval parameter programming, robust optimization method, and mixed-integer linear programming within a two-stage stochastic programming optimization framework. In the IRTMLP, uncertainties presented in terms of probability distributions and discrete intervals can be reflected. Moreover, the approach improves upon the previous stochastic programming method and thus has the following four major advantages. First, the IRTMLP approach can incorporate pre-defined irrigation water policies directly into its optimization framework, and second, it can readily facilitate dynamic analysis of water-saving irrigation pattern planning for irrigation water management. Third, it can explicitly account for the variability of the second-stage variables within a conventional two-stage stochastic programming context. Fourth, it can generate more flexible solutions under different robustness levels. The IRTMLP approach is applied to a case study of crop area planning in the middle reaches of the Heihe River Basin, northwest China. Therefore, a variety of decision alternatives for binary and continuous variables can be generated by giving different robustness levels, which will demonstrate how the developed approach can provide desired and stable solutions. In addition, the results can support in-depth analysis of the interrelationships among system benefits, robustness levels and the system-failure risk levels. These results can provide more reliable scientific basis for supporting irrigation water management under arid and semiarid environments. Graphical abstract Image 1 Highlights • Water-saving irrigation pattern is adopted for economic crops in study area when the robustness level is increased. • The results show that economic crops are highly encouraged in the decision-making process. • The recourse costs would increase with the robustness levels increased. • The system benefits would decrease as the robustness levels increased. • The solutions can illustrate the tradeoffs among system benefits, robustness levels and risk levels. [ABSTRACT FROM AUTHOR]

Highlights • An Interval-based Fuzzy Chance-constrained Irrigation Water Allocation model with double-sided fuzziness is developed. • The approach is applied to Heihe River Basin in northwest China for supporting irrigation water management. • A lower confidence level and a minimum reliability scenario can provide maximized system benefits. • The results can reflect interrelationships among system benefits, confidence levels, reliability levels and risk levels. Abstract This study presents an Interval-based Fuzzy Chance-constrained Irrigation Water Allocation (IFCIWA) model with double-sided fuzziness for supporting irrigation water management. It is derived from incorporating double-sided chance-constrained programming (DFCCP) into an interval parameter programming (IPP) framework. The model integrates interval linear crop water production functions into its general framework for irrigation water allocation. Moreover, it can deal with uncertainties presented as discrete intervals and fuzziness. It can also allow violation of system constraints with double-sided fuzziness, where each confidence level consists of two reliability scenarios (i.e. minimum and maximum reliability scenarios). To demonstrate its applicability, the model is then applied to a case study in the middle reaches of the Heihe River Basin, northwest China. Therefore, optimal solutions have been generated for irrigation water allocation under uncertainty. The results indicate that planning under a lower confidence level and a minimum reliability scenario can provide maximized system benefits. System benefits under the high water level are [2.659, 7.913] × 109 Yuan when α = 0 , [2.650, 7.822] × 109 Yuan when α = 0.5 and [2.642, 7.734] × 109 Yuan when α = 1.0 under the minimum reliability scenario. Furthermore, the results can support in-depth analysis of interrelationships among system benefits, confidence levels, reliability levels and risk levels. These results can effectively provide decision-support for managers identifying desired irrigation water allocation plans in study area. [ABSTRACT FROM AUTHOR]

Nonlinear and conflicting objectives as well as complex uncertainties are commonly encountered by irrigation-water managers. To address such problems, an interval nonlinear multiobjective programming model with fuzzy-interval credibility constraint (FIC-INMP) is proposed for crop water allocation. The FIC-INMP model integrating interval programming, nonlinear multiobjective programming and fuzzy-interval credibility-constrained programming could address not only the conflicts of multiple nonlinear objectives under interval uncertainty, but also the fuzziness expressed as fuzzy-interval membership function. Moreover, an interval fuzzy weighted (IFW) method is proposed to solve developed model by integrating fuzzy weighted programming approach and interval Zimmermann fuzzy method. The FIC-INMP and IFW are applied to Yingke Irrigation District to plan crop monthly water allocation and demonstrate their applicability. By fully considering the main factors in allocation, including concerns of different decision makers, normal growth of crops, local water balance and uncertainties existing in allocation, optimal crop water-allocation schemes can be obtained via the FIC-INMP and IFW. The optimal results offer abundant schemes to decision makers by trading off benefit and risk. In addition, from the comparison between single objective and multiobjective model, the multiobjective model shows better practicality due to more reasonable water allocation in critical water demand period of crops. These results can effectively contribute to the local irrigation water management and ecological restoration. [ABSTRACT FROM AUTHOR]

Abstract The formation of secondary organic aerosol (SOA) from isoprene ozonolysis was investigated using a FEP Teflon reactor with and without the presence of H 2 O, CO, SO 2 and UV-light irradiation (365 nm) to reveal their possible influence on SOA formation. Compared with the base experiment (isoprene + O 3) under dark condition, the presence of 2000 ppm H 2 O and 1000 ppm CO could remarkably suppress SOA formation from isoprene ozonolysis, with SOA yields reduced from 2.96% to 1.47% and 2.08%, respectively. The evident reduction of SOA yields from isoprene ozonolysis with the presence of H 2 O and CO was mainly ascribed to the suppression of Stable Criegee Intermediates (SCIs). In contrast, the particle yield from isoprene ozonolysis with the presence of SO 2 pronouncedly increased from 2.96% to 57.9%, suggesting that the oxidation of SO 2 by SCIs made great contribution to the particle formation. The SOA or particle yields from all the reaction systems with and without presence of H 2 O, CO and SO 2 reduced more than 27% under the UV-light irradiation with respect to dark condition, which were mainly attributed to the SCIs photolysis. The contribution of OH channel to SOA formation from isoprene ozonolysis was estimated to be less than 30%. Considering the 50% reduction of SOA yield from isoprene ozonolysis under light irradiation, the disappearance of the component with low O:C and H:C and high molecule weight in the SOA sample collected under light irradiation indicated the polymerization of unsaturated SCIs might be an important SOA formation channel besides the oligomerization of SCIs, HCHO, and MACR from isoprene ozonolysis under dark condition. Graphical abstract Image 1 Highlights • UV-light could remarkably reduce SOA formation from isoprene ozonolysis. • SCIs formed from isoprene ozonolysis played key role in SOA formation. • Polymers with high C/H and O/H ratios were found in the SOA from isoprene ozonolysis. [ABSTRACT FROM AUTHOR]

Highlights • A double-side stochastic chance-constrained linear fractional programming (DSCLFP) model is developed under uncertainty. • The model directly addresses two objectives, and reflects water productivity. • A non-equivalent but sufficient linearization form of the model is provided and proved. • The model is applied to a case study for optimal irrigation water allocation in the middle reaches of Heihe River Basin. • The solutions provide tradeoffs among water productivity, confidence level and constraint-violation risk level. Abstract A double-sided stochastic chance-constrained linear fractional programming (DSCLFP) model is developed for managing irrigation water under uncertainty. The model is developed by incorporating double-sided stochastic chance-constrained programming (DSCCP) into a linear fractional programming (LFP) optimization framework. It can address ratio optimization problems with double-sided randomness (i.e. both left-hand and right-hand sides). More importantly, it also improves upon the existing stochastic chance-constrained programming for handing random uncertainties in the left-hand and right-hand sides of constraints simultaneously. A non-equivalent but sufficient linearization form of the DSCLFP is provided and proved, which will greatly reduce the computational burden. Then, the model is applied to a case study in Yingke Irrigation District (YID) in the middle reaches of the Heihe River Basin, northwest China. Four confidence levels (e.g. α i = 0.85, 0.90, 0.95 and 0.99) are provided to examine and compare the results. The objective function values are slightly decreased from 5.284 Yuan/m3 to 5.276 Yuan/m3 when α i level is raised from 0.85 to 0.99. The results from the DSCLFP can identify desired irrigation water allocation plans under the objective function of maximizing water productivity under different confidence levels. Therefore, the results can provide tradeoffs among water productivity, confidence level and constraint-violation risk level. Moreover, comparisons with double-sided stochastic chance-constrained linear programming (DSCLP) model and deterministic model are introduced to highlight advantages and feasibility of the developed model. Therefore, these results can provide decision-support for managers in arid areas. [ABSTRACT FROM AUTHOR]

Ba 2 REAlO 5 (RE = Dy, Er, Yb) powders were synthesized by a solid state reaction method, followed by cold pressing and sintering to produce pellets for hot corrosion tests. When exposed to V 2 O 5  + Na 2 SO 4 molten salt at 900 °C and 1000 °C for 4 h and 20 h, REVO 4 , Ba 3 (VO 4 ) 2 and BaAl 2 O 4 formed as corrosion products due to chemical interactions between the ceramics and the molten salt, which were temperature and time independent. After the hot corrosion tests at 1000 °C, continuous, dense reaction layers with a thickness of ∼80 μm formed on the sample surfaces, which had an effective function on suppressing further penetration of the molten salt. The hot corrosion mechanisms of Ba 2 REAlO 5 are proposed based on Lewis acid-base rule, phase diagrams and thermodynamics. From a thermodynamics perspective, the molten salt directly reacting with Ba 2 REAlO 5 is difficult compared with Yb 2 O 3 , Al 2 O 3 and BaO. [ABSTRACT FROM AUTHOR]

In this study, a simulation-based multi-objective two-level optimization decision-making approach is developed for optimal irrigation water allocation, improving irrigation water productivity and controlling regional accumulated salts. Techniques of multi-objective programming, two-level programming and simulation model of water and salt physical movement process are incorporated into the modeling framework. The simulated processes are parameterized and calibrated with field experimental data while the optimization model is used to generate optimal solutions though predefined objectives and the associated constraints. This model is applied to a case study on irrigation water allocation in the Jiefangzha Irrigation Subarea in Hetao Irrigation District, Northwest China. Firstly, the study area is delineated into several homogeneous irrigation decision-making units (IDMUs) for better characterizing their spatial variability because it's spatially heterogeneous. Afterwards, decomposition-coordination algorithm is introduced to solve such an integrated simulation-based multi-objective two-level optimization model. Finally, optimal solutions of irrigation water allocation for different crops during crop growth periods in different IDMUs can be obtained for supporting sustainable strategies of irrigation. The results can achieve balanced tradeoffs between different stakeholders (i.e., the upper-level decision-makers and the lower-level farmers) and between conflicting economic objectives and environmental objectives. Moreover, optimal solutions have a slight increase in economic returns over the baseline scenario (i.e., status quo), but the irrigation water productivity is increased by nearly 60% due to less irrigation water used. Regional accumulated salts can be controlled because the soil salinity is constrained within the predetermined salt accumulation constraint. Therefore, these findings can provide evidence for efficient use of irrigation water resources and further support of sustainable irrigated agriculture. • A simulation-based multi-objective two-level optimization model is developed. • This study addresses three objectives, and reflects sequential decisions. • An efficient algorithm is introduced to solve such an integrated model. • The study area is delineated into several irrigation decision-making units. • The results balance tradeoffs between economic and environmental objectives. [ABSTRACT FROM AUTHOR]

LaPO 4 powders were produced by a chemical co-precipitation and calcination method. The ceramic exhibited a monazite structure, kept phase stability at 1400 °C for 100 h, and had low thermal conductivity (~ 1.41 W/m K, 1000 °C). LaPO 4 /Y 2 O 3 partially stabilized ZrO 2 (LaPO 4 /YSZ) double-ceramic-layer (DCL) thermal barrier coatings (TBCs) were fabricated by air plasma spray. The LaPO 4 coating contained many nanozones. Thermal cycling tests indicated that the spallation of LaPO 4 /YSZ DCL TBCs initially occurred in the LaPO 4 coating. The failure mode was similar to those of many newly developed TBCs, probably due to the low toughness of the ceramics. LaPO 4 /YSZ DCL TBCs were highly resistant to V 2 O 5 corrosion. Exposed to V 2 O 5 at 700–900 °C for 4 h, La(P,V)O 4 formed as the corrosion product, which had little detrimental effect on the coating microstructure. At 1000 °C for 4 h, a minor amount of LaVO 4 was generated. [ABSTRACT FROM AUTHOR]

In this study, a fuzzy linear fractional programming (FLFP) approach with double-sided fuzziness is developed for optimal irrigation water allocation under uncertainty. The FLFP model can be derived from incorporating double-sided fuzzy chance-constrained programming (DFCCP) into linear fractional programming (LFP) optimization framework. The developed model can deal with uncertainty presented as fuzziness in both right-hand and left-hand sides of constraints. Moreover, it has advantages in: (1) addressing two objectives directly without considering subjective factors, (2) effectively reflecting economic water productivity between total system economic benefit and total irrigation water use, (3) introducing the concept of confidence levels of fuzzy constraints-satisfaction under both the minimum and maximum reliabilities to generate more flexible solutions and (4) facilitating in-depth analysis of interrelationships among economic water productivity, system benefits and varying confidence levels. The model is applied to a case study of irrigation water allocation in the middle reaches of Heihe River Basin, northwest China. The optimal irrigation water allocation solutions from the FLFP model can be obtained. These results can provide decision-support when deciding on selecting reasonable irrigation water resources management and agricultural production. [ABSTRACT FROM AUTHOR]

An inexact nonlinear m λ -measure fuzzy chance-constrained programming (INMFCCP) model is developed for irrigation water allocation under uncertainty. Techniques of inexact quadratic programming (IQP), m λ -measure, and fuzzy chance-constrained programming (FCCP) are integrated into a general optimization framework. The INMFCCP model can deal with not only nonlinearities in the objective function, but also uncertainties presented as discrete intervals in the objective function, variables and left-hand side constraints and fuzziness in the right-hand side constraints. Moreover, this model improves upon the conventional fuzzy chance-constrained programming by introducing a linear combination of possibility measure and necessity measure with varying preference parameters. To demonstrate its applicability, the model is then applied to a case study in the middle reaches of Heihe River Basin, northwest China. An interval regression analysis method is used to obtain interval crop water production functions in the whole growth period under uncertainty. Therefore, more flexible solutions can be generated for optimal irrigation water allocation. The variation of results can be examined by giving different confidence levels and preference parameters. Besides, it can reflect interrelationships among system benefits, preference parameters, confidence levels and the corresponding risk levels. Comparison between interval crop water production functions and deterministic ones based on the developed INMFCCP model indicates that the former is capable of reflecting more complexities and uncertainties in practical application. These results can provide more reliable scientific basis for supporting irrigation water management in arid areas. [ABSTRACT FROM AUTHOR]

The characteristics of the agricultural water management system is its great complexity and uncertainty as well as dynamic variations in the system components, which results in dynamic characteristics in optimizing the agricultural water allocation and crop area planning. In this study, an interval multistage joint-probabilistic left-hand-side chance-constrained programming (IMJLCP) model is developed for crop area planning in response to these issues. This method is derived from incorporating the techniques of multistage stochastic programming and joint-probabilistic left-hand-side chance-constrained programming within a general interval optimization framework. It can address uncertainties presented as both discrete intervals and probability distributions, and also reflect dynamic characteristics of the system conditions. Moreover, it can reflect randomness in the left-hand-side of the constraints and examine the reliability level of satisfying constraints at both joint and individual probabilities. The developed method is applied to a case study of dynamic agricultural water management and irrigated crop area planning in different growth stages in the middle reaches of Heihe River Basin, taking groundwater and surface water use into account. Six scenarios with different joint (i.e. p = 0.01, 0.05 and 0.1) and individual probabilities (i.e. same and increasing) of the irrigation quota are examined, and a multilayered scenario tree will be provided for a dynamic analysis in a planning horizon. The results indicate that different levels of constraints violation reflect the attitudes of managers to economic benefit and risk. Furthermore, it can help managers to identify desired decision alternatives in intra- and inter-seasonal water allocation among different crops in different subareas. This application makes it highly feasible to enhance the efficiency of irrigation water and ensure sustainable use of water resources, especially for the arid regions dominated by agriculture. [ABSTRACT FROM AUTHOR]

Hot corrosion behavior of Ba 2 REAlO 5 (RE = Dy, Er, Yb) ceramics exposed to V 2 O 5 molten salt at 900 °C and 1000 °C was investigated, providing a better understanding of their corrosion resistance as promising thermal barrier coatings. Obvious surface reactions occurred forming continuous, dense reaction layers on the top surfaces of the samples, the types of corrosion products being temperature and time independent. After heat treatment for 4 h and 20 h in V 2 O 5 salt at the two temperatures, the corrosion products consisted of REVO 4 , Ba 2 REV 3 O 11 and BaAl 2 O 4 (RE = Dy, Er, Yb). Prolonged heat treatment and elevated temperature promoted the growth of Ba 2 REV 3 O 11 and REVO 4 grains. The reaction layer had a positive function on suppressing further penetration of the molten salt. The mechanism by which the corrosion reaction occurs is proposed based on Lewis acid-base rule, phase diagrams and thermodynamics. [ABSTRACT FROM AUTHOR]

Yb 2 O 3 stabilized ZrO 2 (YbSZ) doped with different TiO 2 contents were produced, and their phase structure, thermal conductivities and thermal expansion coefficients were investigated. A new solid-solution model is proposed, i.e. Ti 4+ would take the interstitial sites when its content is below a critical value (≤2.5 mol%) and then substitute for Zr 4+ . The abnormal lattice volume and thermo-physical properties of 2.5 mol% TiO 2 doped YbSZ, and the positive effects of TiO 2 doping on the thermal conductivity at moderate doping level are consistent with the new defect model. However, monoclinic phase is formed when the TiO 2 content reaches to 10 mol% and its content increases with doping content, which have negative influence on the thermo-physical properties. Considering the comprehensive properties, 10 mol% TiO 2 doped YbSZ is considered as a promising thermal barrier coating ceramic. [ABSTRACT FROM AUTHOR]

The vague and fuzzy parametric information is a challenging issue in irrigation water management problems. In response to this problem, a generalized fuzzy credibility-constrained linear fractional programming (GFCCFP) model is developed for optimal irrigation water allocation under uncertainty. The model can be derived from integrating generalized fuzzy credibility-constrained programming (GFCCP) into a linear fractional programming (LFP) optimization framework. Therefore, it can solve ratio optimization problems associated with fuzzy parameters, and examine the variation of results under different credibility levels and weight coefficients of possibility and necessary. It has advantages in: (1) balancing the economic and resources objectives directly; (2) analyzing system efficiency; (3) generating more flexible decision solutions by giving different credibility levels and weight coefficients of possibility and (4) supporting in-depth analysis of the interrelationships among system efficiency, credibility level and weight coefficient. The model is applied to a case study of irrigation water allocation in the middle reaches of Heihe River Basin, northwest China. Therefore, optimal irrigation water allocation solutions from the GFCCFP model can be obtained. Moreover, factorial analysis on the two parameters (i.e. λ and γ ) indicates that the weight coefficient is a main factor compared with credibility level for system efficiency. These results can be effective for support reasonable irrigation water resources management and agricultural production. [ABSTRACT FROM AUTHOR]

Hot corrosion behavior of (Gd 0.9 Sc 0.1 ) 2 Zr 2 O 7 ceramic exposed to V 2 O 5 molten salt at 700–1000 °C was investigated, providing better understanding of its corrosion resistance as a promising thermal barrier coating. Obvious corrosion reaction occurred between (Gd 0.9 Sc 0.1 ) 2 Zr 2 O 7 and V 2 O 5 molten salt after 4 h heat treatment, corrosion products being temperature dependent. At 700 °C, large amount of Sc 2 O 3 doped ZrV 2 O 7 and GdVO 4 , together with a minor amount of Sc 2 O 3 -stabilized tetragonal ZrO 2 ( t -ZrO 2 ), formed on the sample surfaces. With the increase of the test temperature, Sc 2 O 3 doped ZrV 2 O 7 turned to decompose, leading to the formation of more t -ZrO 2 . At 900 °C and 1000 °C, the corrosion products were composed of GdVO 4 and t -ZrO 2 . The mechanism by which the corrosion reaction occurs is proposed based on phase diagrams and Lewis acid-base rule. [ABSTRACT FROM AUTHOR]

Coke deposition is one of the main reasons for catalyst deactivation, which is often associated with coverage of the active sites and diffusion restrictions. In this article, the self-diffusion coefficient of methane in ZSM-5 (MFI) with different amounts of coke is studied through molecular dynamics simulation combining hard-sphere and pseudo-particle modeling at a gas loading of 4 molecules per unit cell at 723 K. The T12 tetrahedral sites are considered as the possible coke deposition sites at which the pore is blocked. It is shown that the self-diffusion coefficient of methane in ZSM-5 without coke ( D 0 ) is approximately 7.0 × 10 −9 m 2 /s. Two coke distribution models are proposed to simulate the actual process of coke formation. At the initial stage of coke deposition, the coke with uniform distribution has little influence on the diffusion process. Once the coke deposits are randomly concentrated on some sites and a few pores are therefore completely blocked, the coke has a significant influence on the self-diffusion coefficient, which decreases to 37.0% of D 0 almost linearly with increasing coke amount to 20%. The distribution of coke deposition is the result of the coupling of reaction and diffusion processes. These results may be useful for understanding the reaction–diffusion coupling mechanism of the catalyst deactivation. [ABSTRACT FROM AUTHOR]