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Global precipitation products (GPPs) are vital in weather forecasting, efficient water management, and monitoring floods and droughts. However, the precision of these datasets varies considerably across different climatic regions and topographic conditions. Therefore, the accuracy assessment of the precipitation dataset is crucial at the local scale before its application. The current study initially compared the performance of recently modified and upgraded precipitation datasets, including Climate Research Unit Time-Series (CRU TS v4.08), fifth-generation ERA5-Land (ERA-5), Integrated Multi-satellite Retrievals for GPM (IMERG) final run (IMERG v07B), and Multi-Source Weighted-Ensemble Precipitation (MSWEP v2.8), against ground observations on the provincial basis across Pakistan from 2003 to 2020. Later, the study area was categorized into four regions based on the elevation to observe the impact of elevation gradients on GPPs' skills. The monthly and seasonal precipitation estimations of each product were validated against in situ observations using statistical matrices, including the correlation coefficient (CC), root mean square error (RMSE), percent of bias (PBias), and Kling–Gupta efficiency (KGE). The results reveal that IMERG7 consistently outperformed across all the provinces, with the highest CC and lowest RMSE values. Meanwhile, the KGE (0.69) and PBias (−0.65%) elucidated, comparatively, the best performance of MSWEP2.8 in Sindh province. Additionally, all the datasets demonstrated their best agreement with the reference data toward the southern part (0–500 m elevation) of Pakistan, while their performance notably declined in the northern high-elevation glaciated mountain regions (above 3000 m elevation), with considerable overestimations. The superior performance of IMERG7 in all the elevation-based regions was also revealed in the current study. According to the monthly and seasonal scale evaluation, all the precipitation products except ERA-5 showed good precipitation estimation ability on a monthly scale, followed by the winter season, pre-monsoon season, and monsoon season, while during the post-monsoon season, all the datasets showed weak agreement with the observed data. Overall, IMERG7 exhibited comparatively superior performance, followed by MSWEP2.8 at a monthly scale, winter season, and pre-monsoon season, while MSWEP2.8 outperformed during the monsoon season. CRU TS showed a moderate association with the ground observations, whereas ERA-5 performed poorly across all the time scales. In the current scenario, this study recommends IMERG7 and MSWEP2.8 for hydrological and climate studies in this region. Additionally, this study emphasizes the need for further research and experiments to minimize bias in high-elevation regions at different time scales to make GPPs more reliable for future studies. [ABSTRACT FROM AUTHOR]

Understanding the intricate relationship between drought stress and corn yield is crucial for ensuring food security and sustainable agriculture in the face of climate change. This study investigates the subtle effects of drought stress on corn physiological, morphological, and spectral characteristics at different growth stages, in order to construct a new drought index to characterize drought characteristics, so as to provide valuable insights for maize recovery mechanism and yield prediction. Specific conclusions are as follows. Firstly, the impact of drought stress on corn growth and development shows a gradient effect, with the most significant effects observed during the elongation stage and tasseling stage. Notably, Soil and Plant Analyzer Development (SPAD) and Leaf Area Index (LAI) are significantly affected during the silking stage, while plant height and stem width remain relatively unaffected. Secondly, spectral feature analysis reveals that, from the elongation stage to the silking stage, canopy reflectance exhibits peak–valley variations. Drought severity correlates positively with reflectance in the visible and shortwave infrared bands and negatively with reflectance in the near-infrared band. Canopy spectra during the silking stage are more affected by moderate and severe drought stress. Thirdly, LAI shows a significant positive correlation with yield, indicating its reliability in explaining yield variations. Finally, the yield-related drought index (YI) constructed based on Convolutional Neural Network (CNN), Random Forest (RF) and Multiple Linear Regression (MLR) methods has a good effect on revealing drought characteristics (R = 0.9332, p < 0.001). This study underscores the importance of understanding corn responses to drought stress at various growth stages for effective yield prediction and agricultural management strategies. [ABSTRACT FROM AUTHOR]

Accurate monitoring of crop drought thresholds at different growth periods is crucial for drought monitoring. In this study, the canopy temperature (Tc) of winter wheat ('Weilong 169' variety) during the three main growth periods was extracted from high-resolution thermal and multispectral images taken by a complete unmanned aerial vehicle (UAV) system. Canopy-air temperature difference (ΔT) and statistic Crop Water Stress Index (CWSIsi) indicators were constructed based on Tc. Combined experiment data from the field and drought thresholds for the ΔT and CWSIsi indicators for different drought levels at three main growth periods were monitored. The results showed a strong correlation between the Tc extracted using the NDVI-OTSU method and ground-truth temperature, with an R2 value of 0.94. The CWSIsi was more stable than the ΔT index in monitoring the drought level affecting winter wheat. The threshold ranges of the CWSIsi for different drought levels of winter wheat at three main growth periods were as follows: the jointing–heading period, where the threshold ranges for normal, mild drought, moderate drought, and severe drought are <0.30, 0.30–0.42, 0.42–0.48, and >0.48, respectively; the heading–filling period, where the threshold ranges for normal, and mild, moderate, and severe drought are <0.33, 0.33–0.47, 0.44–0.53, and >0.53, respectively; and the filling–maturation period, where the threshold ranges for normal, mild drought, moderate drought, and severe drought are <0.41, 0.41–0.54, 0.54–0.59, and >0.59, respectively. The UAV thermal threshold method system can improve the accuracy of crop drought monitoring and has considerable potential in crop drought disaster identification. [ABSTRACT FROM AUTHOR]

LaGdFeCuO3 composite catalysts were prepared by a hydrothermal method using glucose as the carbon source and were used to investigate the properties of CO2 activation and hydrogenation to light olefins. Various characterization techniques have been employed to reveal the relationship between the catalytic activity and the catalyst structure. The results demonstrated that the morphology of the sample is a cage branch chain structure. Gd decreases the interface effect and structural stability, enhances active metal exudation, and facilitates lattice oxygen migration. In CO2 hydrogenation, the predominant products were C2–C4 hydrocarbons in the Gd doped LaFeCuO3 samples. The catalytic activity of Cu doping first increased and subsequently reduced with an increase in the Cu/Fe molar ratio. When the Cu/Fe molar ratio is 0.75, the olefin selectivity is the highest. The results demonstrate the relationship between olefin selectivity and perovskite oxygen mobility, as determined from oxygen vacancies and oxygen diffusivity, and the anchoring effect of reduced metal nanoparticles that create C–O bonds on the catalytic surface. These investigations offer a theoretical framework for the creation of dual-function Fe-based perovskite catalysts for CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

The simultaneous realization of high olefin/paraffin (O/P) ratio and low CH4 selectivity has always been a bottleneck for the conversion of syngas to high‐value olefins (HVOs). Magadiite (MAG) is a layered silicate material with active SiOH, which increases the interlayer charge density and ion‐exchange ability. Herein, a MAG‐supported, Mn‐modified Fe3O4 microsphere catalyst exhibits excellent CO conversion of 76.5 % and HVO selectivity, with a high O/P ratio of 5.02 and low CH4 selectivity of 16.1 % for conversion of syngas to HVOs. The layered structure of the MAG support promotes dispersion of the active centers and the Mn promoter improves the basic properties of the catalyst. Moreover, the Mn promoter and MAG support have a synergistic effect, which promotes CO dissociation and suppresses H2 adsorption, thereby resulting in high HVO selectivity and low CH4 selectivity. [ABSTRACT FROM AUTHOR]

In order to promote the commercialization of perovskite solar cells, gas‐quenching is considered to be a promising technique for perovskite film fabrication. However, when handling with methylammonium‐free (MA‐free) perovskites, it is often difficult to obtain high‐quality perovskite films by gas‐quenching. Herein, formate additives are employed to regulate the crystallization of MA‐free perovskite, and improve the quality of perovskite films. Different additives of formamidine formate (FAFO) and potassium formate (KFO) is compared to investigate the role of formate groups in the crystallization of perovskite films prepared by gas‐quenching. The FAFO additive facilitates the perovskite crystallization in (001) orientation whereas KFO favors for (111) orientation. The MA‐free device with addition of FAFO demonstrate a champion power conversion efficiency of 20.94 %, compared to that of 20.14 % for KFO devices. In addition, FAFO device also exhibits improved thermal stability in ambient condition without encapsulation, extending the T80 lifetime by 18 times compared to the pristine device. [ABSTRACT FROM AUTHOR]

Although Fe-based catalysts have made significant progress in Fischer–Tropsch synthesis, the effect of residual sodium on the structural properties and catalytic performance of Fe-based catalysts has been controversial. Herein, we report the positive role of residual sodium in the structural properties and performance of FeAlNa catalysts for olefins synthesis from syngas. Meanwhile, the as-prepared catalysts were characterized by the multiple characterization technique to reveal the positive role of residual sodium on the structural properties. The characterization results revealed that the residual sodium improved the reduction behavior of Fe species and adsorption ability of CO, and inhibited the secondary hydrogenation due to its weak adsorption ability of H2. Moreover, the residual sodium inhibited the interaction between Fe and Al. Importantly, a high olefins/paraffins ratio of 6.19 and low CH4 selectivity of 12.8% were achieved on the residual sodium modified FeAlNa catalyst. An in-depth understanding of the structural properties and catalytic performance of residual sodium on FeAl-based catalysts can provide a theoretical basis for the development of novel efficient catalysts and large-scale applications for olefins synthesis from syngas. [ABSTRACT FROM AUTHOR]

As the country hosting the most significant number of refugees in Europe, Germany's Merkel government's refugee policy has been repeatedly adjusted and plagued by inconsistencies and management failures. What factors have influenced the formation of the Merkel government's refugee policy and its two shifts? The traditional rational decision-making model does not effectively explain government decisions' motivation in complex challenges. This article develops a framework for analyzing "bounded rational decision-making". It identifies the three factors that influenced the Merkel government's refugee policy: (a) strict border controls, (b) welcome culture, and (c) welcome culture under restrained policies. It explains the process and logic of their development. Based on the theory of "bounded rational decision making", the article examines the "key events and problem identification", "goal selection", "national interests", and "political psychology". We found that in the early stages of the refugee crisis, (a) public opinions and pressure, (b) the pursuit of a positive national image, and (c) a shift in the leader's psychology led Merkel to shift away from a pragmatic and rational course. These factors led to the first shift in German refugee policy from "hesitation" to a "welcoming culture". At the end of 2015, however, the shortcomings of the irrational policy were quickly revealed, and the frequency of refugee-related social problems reversed German public opinion, forcing Merkel's government to seek a balance between humanitarianism and national interests. As a result, refugee policy was adjusted for the second time, returning to a strict refugee examination system. The development of the Merkel government's refugee policy exposed the shortcomings of the traditional crisis decision-making model. Moreover, it provided a new perspective for rethinking the governance of the refugee crisis. [ABSTRACT FROM AUTHOR]

Although heteroatom doped Fe-based catalysts have made significant process in CO 2 hydrogenation, designing a tailor-made catalyst with excellent catalytic performance remains a challenge. In this work, a series of heteroatom doped Na-FeM/ZrO 2 (M = Ga, Mn, Zn, Co, and In) catalysts were prepared by the urea self-combustion method. Meanwhile, the structure and physicochemical properties of these catalysts were analyzed by various characterizations. In detail, Zn doping was more favorable for light olefin production. Na-FeZn/ZrO 2 catalysts exhibited CO 2 conversion of 31.3 % and light olefins selectivity of 41.4 % with olefins/paraffins (O/P) ratio of 4.93. H 2 -TPR and in situ XRD results revealed that Zn promoted reduction of the catalyst and the formation of ZnO species, which inhibited the secondary hydrogenation of the generated olefins. This work contributes to the development of novel catalysts for efficient CO 2 hydrogenation via understanding the relationship between structure and catalytic performance. [Display omitted] • The performance of different Fe-based catalysts for CO 2 hydrogenation is elucidated. • Zn and Co doping exhibited the highest O/P ratio and CO 2 conversion, respectively. • The structure-performance relationship of catalysts is clearly clarified. • Different from Ga, doping with Zn, Co and In facilitates the reduction of Fe species. [ABSTRACT FROM AUTHOR]

Since the end of the Cold War, the former Soviet states of Europe, located at the crossroads of Europe and Asia, have been the site of a political game between the great powers, gradually developing a left-right strategy. This paper constructs the explanatory theory of hedging strategy and argues that post-socialist European countries, collectively referred to as 'New Europe', have navigated a middle way between balance and followup strategies called compound hedging. Starting at the regional scale, this paper discusses three issues, i.e., whether the new Europe has adopted a hedging strategy, why they adopt a hedging strategy, and the policy performance and effectiveness of hedging in the security and economic fields. Specifically, New Europe has implemented diversified fuzzy strategies amidst the transatlantic alliances and Eurasian powers, avoided security risks from Russia through cooperation with NATO, and balanced interest risks caused by European Union pressure through contacts with the United States, Russia, China and other countries. Although New Europe has realized certain practical strategic effects, it still faces difficulties (e.g., structural pressure changes, divergences between old and New Europe, and a lack of hedging capacities and motivations), and its policy space remains narrow and uncertain. [ABSTRACT FROM AUTHOR]

Since the turn of the 21st century, China has leveraged the international environment in its favour to achieve a spectacularly rapid rise, a success that Chinese strategic policymakers attribute in part to 'seizing the strategic window of opportunity'. How has China perceived the international environment and shaped the narrative of its macro-strategy? What impact has it had on China and the world? The article explores the evolution of the strategic narrative of the 'window of opportunity' in three stages since the 21st century and explores its impact in terms of quantity and keyword mapping by analysing the narrative texts of China's 'discourse coalition' (government, official media and intellectual elites). The study found that China's macro-strategic narrative is primarily driven by the official political and semi-official intellectual elites and places a premium on domestic political persuasion rather than external displays of strategic intent. It combines classical and modern philosophical thinking and methodology with the two core objectives of 'maintaining peace' and an 'economic priority'. Over 20 years, the trend of narrative production of the 'strategic opportunity period' has shown a concentrated emergence and fluctuating decline, and its narrative elements have been enriched, interlinked and aligned with the narrative of the CPC's core policies. The narrative of the 'strategic opportunity period' has been a powerful force in building domestic legitimacy, guaranteeing partial fulfilment of strategic objectives and offering lessons for other countries to learn from. Inevitably, the narrative faces a number of dilemmas and challenges. [ABSTRACT FROM AUTHOR]

[Display omitted] • The performance of Co-Al-O catalysts for CO 2 methanation at 160 °C is elucidated. • CO 2 methanation pathways of different Co species (Co0/Co2+) is clarified. • The structure-performance relationship of catalysts is clearly clarified. • Co promotes the formation of a formate intermediate that determines the rate of the reaction. The development of low-temperature CO 2 methanation catalysts with excellent performance has been challenging. Herein, we report a CoAlO catalyst derived from layered double hydroxide (LDH) that modulates the Co species of a multifunctional catalyst through a reduction process. The CoAlO catalyst with a surface-coated CoO film achieved CO 2 conversion up to 29.0 % at 160 °C, which was superior to that of noble metal catalysts. The multiple characterizations were used to reveal the relationship between the catalytic activity and the chemical state of Co species. The results showed that the reaction followed the H-assisted activation pathway, where the rate of formate intermediates generation determined the overall reactivity. Meanwhile, the reduction–oxidation (RO) process in the catalyst preparation and the water generated in the reaction could reduce the size of Co particles, which were favorable for CO 2 activation. This work offers a promising catalyst design for low-temperature methanation reaction. [ABSTRACT FROM AUTHOR]

To improve the dry friction behavior of traditional hard coatings, MoS 2 /PTFE lubricating coatings were prepared on the PVD TiN-coated cemented carbide using spray method. The influences of MoS 2 /PTFE lubricating coatings on the primary characteristics of TiN coatings were investigated. Reciprocating sliding tests were carried out with the TiN–MoS 2 /PTFE coated specimen (T-M-P) under dry sliding conditions, and the tribological behaviors were compared to those of the TiN-coated one (T-N). The test results indicated that the adhesion force of coatings with substrate for T-M-P specimen increased, the surface micro-hardness, roughness and friction coefficient significantly decreased. Meanwhile, the surface adhesions and abrasion grooves of T-M-P specimen were reduced, and the main wear forms of T-M-P were abrasion wear and coating delamination. The MoS 2 /PTFE lubricating coatings can be considered effective to improve the friction properties of traditional hard coatings. [ABSTRACT FROM AUTHOR]

Polymethyl methacrylate (PMMA) bone cement is a commonly used filling material in orthopedic surgery. Its good and stable performances make it the most widely used in all kinds of bone cement. With the advancement of the application and research of PMMA bone cement by surgeons, its disadvantages such as non-degradation and non-bioactivity are gradually exposed. In recent years, the biological functions of lactoferrin (LF) have been gradually explored, especially its role in promoting osteogenesis. In this study, LF was modified on the surface of solidified PMMA bone cement (LF/PMMA bone cement) by physical/chemical mixed modification and verified by cytological experiments in vitro. In vitro studies have implicated that PMMA bone cement modified with LF can improve the attachment, expansion, proliferation, extracellular matrix secretion and osteogenic differentiation of mouse preosteoblasts (MC3T3-E1) cells, indicating biocompatibility. This experiment provides a novel insight for improving the biological activity of PMMA bone cement and lays a foundation for broadening the clinical application of PMMA bone cement. [ABSTRACT FROM AUTHOR]

In order to improve the tribological behavior of Si 3 N 4 /TiC ceramics, DLC coating was fabricated on the ceramic surface through magnetron sputtering technology. The surface and cross-section micrographs, the adhesion between coating and substrate, the surface roughness and microhardness of the DLC-coated ceramics were investigated. Reciprocating friction tests sliding against cemented carbide ball were conducted under dry sliding conditions. The test results indicated that the DLC coating possessed superior tribological performance, which was conductive to decreasing the friction coefficient and enhancing the wear resistance of ceramics. The primary mechanisms responsible for performance improvement of the DLC-coated ceramics were attributed to the combined effects of low shear stress, excellent adhesion with substrate, high microhardness and good surface roughness. It was believed that the DLC coating was efficient in improving the load-carrying capacity and expanding the application area of ceramic materials. [ABSTRACT FROM AUTHOR]

To enhance the tribological performance of Si 3 N 4 /TiC ceramics, MoS 2 /PTFE composite coatings were deposited on the ceramic substrate through spraying method. The micrographs and basic properties of the MoS 2 /PTFE coated samples were investigated. Dry sliding friction experiments against WC/Co ball were performed with the coated ceramics and traditional ones. These results showed that the composite coatings could significantly reduce the friction coefficient of ceramics, and protect the substrate from adhesion wear. The primary tribological mechanisms of the coated ceramics were abrasive wear, coating spalling and delamination, and the tribological property was transited from slight wear to serious wear with the increase of load because of the lower surface hardness and shear strength. The possible mechanisms for the effects of MoS 2 /PTFE composite coatings on the friction performance of ceramics were discussed. [ABSTRACT FROM AUTHOR]

PTFE coatings were deposited on the Si 3 N 4 /TiC ceramic substrate by using spray technology. The surface and cross-section micrographs, adhesive force of coatings with substrate, surface roughness and micro-hardness of the coated ceramics were examined. The friction and wear behaviors of ceramic samples with and without coatings were investigated through carrying out dry sliding friction tests against WC/Co ball. The test results indicated that the coated ceramics exhibited rougher surface and lower micro-hardness, and the PTFE coatings can significantly reduce the surface friction and adhesive wear of ceramics. The friction performance of PTFE-coated sample was affected by applied load due to the lower surface hardness and shear strength of coatings, and the main wear failure mechanisms were abrasion wear, coating delamination and flaking. It can be considered that deposition of PTFE coatings is a promising approach to improve the friction and wear behavior of ceramic substrate. [ABSTRACT FROM AUTHOR]

A pixel-based spectral matching method using enhanced vegetation index (EVI) time series from GaoFen-1 (GF-1) Satellite was developed based on spectral similarity value (SSV) and iterative thresholding to map irrigated areas for varying and scattered croplands at high resolution in order to improve understanding of dynamic irrigation pattern. The approach was tested in a typical irrigation district in Northwest China, resulting in 16-m irrigated area maps of the major crops (wheat and maize) for 2015–2018. The results showed an overall accuracy of 92.67% with a Kappa Coefficient of 0.89, producer's accuracy of 97.42%, and user's accuracy of 92.65% for the irrigated area. This method does not require a large number of ground-truth data as training samples, resulting in fast calculation speed, which is different from other supervised classification methods. After obtaining the standard spectrum of the study area, the irrigated areas can be continuously mapped for multi-years. Comparing with the existing global products, these high-resolution maps can depict small and fragmented irrigated croplands effectively with higher accuracy, which benefit local water management, food security analysis, and drought impact assessment, providing the prototype for the regions with fragmented croplands which requires high-resolution products. [ABSTRACT FROM AUTHOR]

Digital image processing has been widely used in the wood industry, and it is expected that the algorithms are accurate and have low computational complexities, especially for the real-time lumber grading and lumber classification processes. This paper investigates variations of deep learning strategies based on ResNet18 for classification of lumber images. The four datasets used in this work were manually marked as lumber defects, wood textures and lumbers by experts. A key ideal is to employ the transfer learning in the context of convolutional neural networks with a classifier layer only training with a small amount of training data for different tasks at the same lumber machinery. Through the expansion of unbalanced samples, the accuracy rate has been effectively improved. The human involvement when needed is kept to a minimum only for the training phase. The proposed approach was independently tested with four datasets, of which 80% of the data is used for training and 20% of the data is used for testing. The classification accuracy of the approach for each of the datasets is 98.16%, 93.32%, 96.64% and 99.50%. The average time for sorting the lumber image was kept at 0.003 s when the system runs on Nvidia GTX860 GPU. [ABSTRACT FROM AUTHOR]

Chitosan-based electroactive paper has been reported as a smart material, which has merits in terms of lightweight, dry condition, biodegradability, sustainability, large displacement output, and low actuation voltage. However, our recent investigations found its actuation performance is highly sensitive to the membrane thicknesses, both on the electrolyte layer and the electrode layer. Focused on this issue, in this paper, we introduce a biopolymer ionic actuator made by multiwalled carbon nanotube, ionic liquid electrode, and polymer-supported chitosan. As a result, we find that chitosan polymer actuator with the thick electrode layer (0.7 mm) behaves with a larger blocking force (9.66 mN) and a smaller displacement (9.53 mm), and the lifetime under applied voltage of 3 V at 0.25 Hz is 1.75 times surpassed the thin one (0.3 mm). In addition to that, we investigate effects of membrane thicknesses on the electrical properties of chitosan polymer actuator, and figure out the relationship between the tensile strength of the membrane and the volume of the ionic solution in the electrolyte layer. [ABSTRACT FROM PUBLISHER]

Recently, chitosan is discovered as a most abundant natural polymer, which is not only a lightweight, low‐cost, sustainable resource with potentials in energy transformation, but also biocompatibility and biodegradability. In this article, they investigated a highly biocompatible chitosan‐based electro‐active polymer (C‐Polymer) actuator composed of multiwall carbon nanotube, ionic liquid, and polymer‐supported chitosan. As a result, after the changed MCNTs rate (20%, 40%, 60%, and 80%) in the electrode membrane, actuation properties of C‐polymer actuator behaved a great enhancement. With the increase of the ratio of MCNTs, the specific capacitance and the electrode resistance were obviously improved, which were 2.02 F/g and 1.32 Ω under rate of 80%, and the maximum displacement and the response speed behaved a peak value of 7 mm (80%) and 0.032 mm/s (80%). Interestingly, it also showed an increasing for the maximum blocking force and response speed under the ratio of 80%, which presented the maximum value of 6.80 mN and 0.11 mN/s. In order to analyze causes for this enhancement, a valid generated strain values were calculated to evaluate the strain on the electrode layer. However, it is exhibited that the generated strain was very small, which almost kept in the value of 0.5%, and it was unrelated to Young's modulus. Moreover, they also found that the resistance and the specific capacitance could strongly affect the electromechanical properties of C‐polymer actuator with different rate of MCNTs, and revealed a vital potential Ramsay rule between the electrochemical properties and electromechanical properties of C‐polymer actuator. POLYM. COMPOS., 39:E228–E235, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Nature offers a wealth of opportunities to solve scientific and technological issues based on its unique structures and function. The dynamic non‐covalent interaction is considered to be the main base of living functions of creatures including humans, animals, and plants. Supramolecular hydrogels formed by non‐covalent bonding interactions has become a unique platform for constructing promising materials for medicine, energy, electronic, and biological substitute. In this review, the self‐assemble principle of supramolecular hydrogels is summarized. Next, the stimulation of external environment that triggers the assembly or disassembly of supramolecular hydrogels are recapitulated, including temperature, mechanics, light, pH, ions, etc. The main applications of bioinspired supramolecular hydrogels in terms of bionic objects including humans, animals, and plants are also described. Although so many efforts are done for revealing the synergized mechanism of the function and non‐covalent interactions on the supramolecular hydrogel, the complexity and variability between stimulus and non‐covalent bonding in the supramolecular system still require impeccable theories. As an outlook, the bioinspired supramolecular hydrogel is just beginning to exhibit its great potential in human life, offering significant opportunities in drug delivery and screening, implantable devices and substitutions, tissue engineering, micro‐fluidic devices, and biosensors. [ABSTRACT FROM AUTHOR]

To enhance the anti-friction and anti-wear properties of the WC/TiC/Co carbide, micro-EDM was selected to fabricate textured micro-holes on the carbide surface, and graphite was embedded into the micro-holes to form self-lubricating tools. Dry machining tests on AISI 1045 hardened steel were carried out with the self-lubricating tool and conventional ones. The cutting temperature and tool wear were investigated and compared. The results showed that the self-lubricating tool embedded with graphite exhibited excellent efficiency and stability in reducing cutting temperature, and then the tool wear was reduced compared to that of the conventional one. Through the analysis of test results and cutting temperature distribution theory, the mechanisms responsible are put forward: the first one is the formation of a graphite film on the tool rake face, which is conducive to reducing the temperature of chip and tool caused by tool-chip friction and chip deformation; the other one is attributed to the reduced actual contact length at the tool-chip interface due to the micro-holes, which is propitious to lower the temperature of chip and tool caused by tool-chip friction, supply more graphite, and store chip debris. [ABSTRACT FROM AUTHOR]

To improve the tribological properties of the cemented carbide, Ti-MoS/Zr composite coatings were deposited on the substrate surface by medium-frequency magnetron sputtering coupled with multi-arc ion plating. The morphology and fundamental properties of the coatings were examined. Dry machining test on AISI 1045 hardened steel was carried out with the coated tool and uncoated tool. The variation of cutting temperature was tested by a TH5104 thermo tracer. The results showed that cutting speed had a profound effect on the cutting temperature. In low-speed cutting of less than 120 m/min, the cutting temperature was decreased by 18-22% and flank wear resistance was improved by 25-30% in comparison with that of uncoated tool, while in high-speed cutting, there was not much difference in cutting performance owing to the high temperature caused by the elevated cutting speed. Through the analysis of cutting heat distribution theory, two responsible mechanisms are found: as lubricating additive between the tool and chip sliding couple, the Ti-MoS/Zr composite coatings contribute to the decrease of average shear stress on the rake face and the thermal barrier effect in heat conduction. These may result in the decrease of the cutting temperature of tool and chip, and hence the improvement of tool wear resistance. [ABSTRACT FROM AUTHOR]

The activity of Ni 3 Sn powder after oxidation-reduction treatment was investigated for producing hydrogen from methanol under different conditions. The treated Ni 3 Sn powder, especially that the Ni 3 Sn oxidized at higher temperature showed a much higher activity than non-treated Ni 3 Sn; compared to Ni 3 Sn oxidized at 1073 K, Ni 3 Sn oxidized at 1373 K showed 10 times higher H 2 and CO generation rates, but similar low CO 2 and CH 4 generation rates. The activity of treated Ni 3 Sn significantly increased with increasing oxidation temperature and decreasing reduction temperature. The activity improvement of treated Ni 3 Sn powder was attributed to the formation of fine nanostructured Ni/SnO 2 particles, which were supposed to be the cause of the improved activity of Ni 3 Sn. [ABSTRACT FROM AUTHOR]

Abstracts A conductive polyaniline-wrapping hollow sulfur composite used as a cathode material for lithium/sulfur batteries was successfully fabricated by a facile and controllable chemical reaction with MCM-41 template. The polyaniline-wrapping hollow sulfur composite had a good reversible capacity of 506.3 mAh g −1 at the 150th cycle, reflecting the low loss of sulfur and polysulfide encapsulated by polyaniline during the charge and discharge cycles. The results of SEM and EIS show that the polyaniline-wrapping hollow sulfur composite presented many good electron-conducting paths for the rechargeability of lithium/sulfur battery. XRD and TG-DSC results revealed the formation of fine sulfur particles encapsulated by polyaniline and sulfur distributed on the polyaniline surface because of low sulfur melting temperature, which was the key reason for the activation. [ABSTRACT FROM AUTHOR]

Remote sensing image scene classification is a fundamental task in intelligent interpretation of remote sensing images. Although Transformers possess a powerful attention mechanism, they require lengthy training procedures to achieve good performance levels. To address this issue, this paper proposes a novel deep learning network model by combining CNN and Swin Transformer named SwinHCST. Firstly, the model uses Weighted Normalized CNN to quickly extract low-level features of the image. Secondly, the Receptive Field Block module facilitates multi-scale information fusion, Thirdly, the Information Fusion Transformer further excavates the deep-level features of the image. Furthermore, this paper has designed a plug-and-play Cross Spatial Information Fusion Block, which is used to encodes dimensional information and extracts global information to enhance information exchange. The scene classification experiments show that the proposed model outperforms other methods on the three selected datasets and can achieve excellent performance without requiring large amounts of data and training. Specifically, the classification accuracy of the proposed method on the three datasets is 93.76%, 93.60%, and 98.10%, which is 1.7% to 3.71% higher than ResNet50 and 3.7% to 5.7% higher than Swin Transformer. [ABSTRACT FROM AUTHOR]

In this study, a visible light‐activated and degradable surface‐enhanced Raman spectroscopy (SERS) substrate was fabricated based on graphite carbon nitride (g‐C3N4) and gold nanoparticle (Au NP) hybrid structures. By using porous structure of g‐C3N4 as the support, Au NP arrays can be formed through sputtering of a thin Au film. Typical surface Raman enhancement effect can be observed by using p‐toluenethiol as the probe molecule. Interestingly, it was found that the Raman signal of probe molecules could be enhanced 2.7 times by pre‐illumination of visible light for a short time within 2 min, while the Raman signal decreased significantly about five times with further long‐term irradiation of more than 60 min. The electromagnetic enhancement effect of Au NP array on semiconductor materials with various extinction coefficients was studied by FDTD simulations. Furthermore, a charge transfer enhancement mechanism was proposed based on band structure of g‐C3N4/Au NP hybrid substrate and molecular orbitals. Our experimental and simulation results demonstrated an approach to construct a visible light‐activated SERS substrate with enhancement and degradation properties based on porous organic semiconductors. [ABSTRACT FROM AUTHOR]

Abstract: A novel sensor material of SnO2 nanocrystals with coral-like porous structures was prepared via a simple wet-chemical approach combining with an annealing process. The microstructure of obtained SnO2 powders were characterized by X-ray diffraction, scanning electron microscope and nitrogen adsorption–desorption experiment. We also investigated their gas sensing performance toward several volatile organic compounds. The obtained sample is found to show excellent sensing performances to the target ethanol owing to the nano coral-like structure providing many quick passages to absorb and desorb gas. Such an unexpected morphology holds substantial promise for rendering SnO2 as a potential gas sensing material for a broad range of future sensor applications. [Copyright &y& Elsevier]

Purpose: To implement a bioinspired methodology using superhydrophobic surfaces suitable for producing smart hydrogel beads in which the bioactive substance is introduced in the particles during their formation. Methods: Several superhydrophobic surfaces, including polystyrene, aluminum and copper, were prepared. Polymeric solutions composed by photo-crosslinked dextran-methacrylated and thermal responsive poly( N-isopropylacrylamide) mixed with a protein (insulin or albumin) were dropped on the superhydrophobic surfaces, and the obtained millimetric spheres were hardened in a dry environment under UV light. Results: Spherical and non-sticky hydrogels particles were formed in few minutes on the superhydrophobic surfaces. The proteins included in the liquid formulation were homogeneously distributed in the particle network. The particles exhibited temperature-sensitive swelling, porosity and protein release rate, with the responsiveness tunable by the dextran-MA/PNIPAAm weight ratio. Conclusions: The proposed method permitted the preparation of smart hydrogel particles in one step with almost 100% encapsulation yield. The temperature-sensitive release profiles suggest that the obtained spherical-shaped biomaterials are suitable as protein carriers. These stimuli-responsive beads could have potential to be used in pharmaceutical or other biomedical applications, including tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

Abstract: Micro-holes were made on the surface of WC/TiC/Co carbide, MoS2 solid lubricants were filled into these micro-holes. Reciprocating sliding tests and dry cutting tests were carried out with this carbide tools. Results showed that the friction coefficient of conventional carbide is much higher than that of the carbide embedded with solid lubricants in sliding tests. The cutting forces, temperature, and friction coefficient at the tool–chip interface of the tool embedded with solid lubricants were reduced compared with that of the conventional tool. Two mechanisms responsible were found, the first one is explained as the formation of self-lubricating film at the tool–chip interface, which was released from the micro-hole and smeared on the rake, and served as lubricating additive; the other one was explained by the reduced contact length at the tool–chip interface, which contributes to the decrease of direct contact area between the chip and rake face. [Copyright &y& Elsevier]

MoS2/Zr composite films were deposited on the cemented carbide YT14 (WC+14%TiC+6%Co) by medium-frequency magnetron sputtered coupled with multi-arc ion plating techniques. The thickness, micro-hardness, and coating/substrate adhesion strength of the coatings were tested. Surface morphologies of the composite coatings, as well as wear features, were investigated by scanning electron microscopy. Dry machining tests on hardened steel were carried out with the coated tool and uncoated YT15 tool. The variation of cutting forces for 45# hardened steel was tested by the Kistler force tester. The result shows that the cutting forces of coated tool were decreased by 25–30%, and flank wear resistance was improved by 30–35% in comparison with the uncoated YT15 tool. Through the analysis of cutting force distribution theory, the lower mean shear stress on the MoS2/Zr-coated tool face leads to the decrease of cutting force and increase of tool wear resistance. [ABSTRACT FROM AUTHOR]

Abstract: Chitosan has been greatly applied in the fields of biomedicine, biomembranes and food/nutrition because of its nontoxic and biocompatible properties. However, water solubility of chitosan at pH<5 strongly limits the use of chitosan-based films when pH stability and low water uptake are required in many actual applications. In this work, silyl chitosan, 3,6-O-di-tertbutyldimethyl silyl chitosan, a chitosan derivative, was synthesized and used to prepare extreme water-repellent films in the whole pH range of 1–14 using a phase separation method that exhibit topography with a three-level hierarchical roughness organization. The polymer also allows posterior chemical modification specifically through the amine group, permitting to control the surface chemistry and wettability. This work not only improve the stabilization of chitosan-based films but also demonstrates the possibility of manufacturing polysaccharide-based superhydrophobic surfaces with potential to be used in anti-bacterial substrates, tissue engineering, food industry and other biomedical applications. [Copyright &y& Elsevier]

Abstract: An electro-sensitive poly(2-acrylamide-2-methylpropane sulfonic acid) (PAMPS) film was fabricated by surface-initiated atom transfer radical polymerization (ATRP) method on silicon substrate. Atomic force microscopy (AFM) experiments in contact mode show that friction force and the adhesion force between the AFM tip and the film may change regularly with the alteration of the applied negative bias voltage between them, indicating that the microscopic wettability of the film can be adjusted by external electric field. On the other hand, the AFM experiments in tapping mode reveal that the film may take corresponding phase change under the electric field. These effects were considered to result from the conformational overturn of the sulfonic groups and the adjacent alkyl chains in the electric field. [Copyright &y& Elsevier]

Solid‐state lithium metal batteries (SSLMBs) with poly (ethylene oxide) (PEO)‐based electrolytes have increasingly become one of the most promising battery technologies due to high energy density and safety. However, adverse electrode/electrolyte interface compatibility issues hinder further application. Herein, a PEO‐based composite solid electrolyte with excellent anode and cathode interfacial compatibility is designed via the coordination modulation strategy induced by lithium difluorobis(oxalato)phosphate (DFBOP). By utilizing this electrolyte, the robust inorganic‐rich interphase involving LiF, LixPOyFz, and P─O components is in situ generated on lithium (Li) anode and LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode surfaces via forceful coordination among PEO, lithium bis(trifluoromethanesulphonyl)imide, and DFBOP and subsequent adjustment of front orbital energy levels. It contributes to homogeneous lithium deposition and an effective impediment of PEO oxidation decomposition at high voltage, promoting superior interfacial stability. Consequently, Li‐symmetric cells with modified electrolyte can achieve a stable cycle over 7000 h at 0.2 mA cm−2. Specially, the cathode electrolyte interphase with a unique organic–inorganic interpenetration network structure enables the 4.5 V Li/NCM811 cells to cycle steadily over 100 cycles, with a high discharge capacity of 215.4 mAh g−1 and initial coulombic efficiency of 91.23%. This research has shed light on the interfacial design of PEO‐based electrolytes from the perspective of electrolyte coordination regulation to construct high‐performance SSLMBs. [ABSTRACT FROM AUTHOR]

The properties of the MoS2/Zr coatings can be significantly affected by the deposition temperature. In this study, the MoS2/Zr composite coatings were fabricated on the cemented carbide surface, utilizing the duplex deposition technology at various deposition temperatures. The effects of deposition temperature on the mechanical and friction properties of the MoS2/Zr coatings were systematically studied. Results exhibited that as the deposition temperature increased, the adhesion force increased first and then decreased, and the coating thickness and micro-hardness gradually increased. Dry sliding tests against a hardened steel ring showed that the tribological behaviors and wear mechanisms of the MoS2/Zr coatings varied with deposition temperature, which were due to the changing mechanical properties of coatings caused by the temperature. The coatings deposited at a temperature of 180 °C and 200 °C possessed preferable comprehensive mechanical and tribological properties. [ABSTRACT FROM AUTHOR]

This study aimed to develop a bilayer active film by using polyvinyl alcohol (PVA)/ethylene-vinyl acetate copolymer (EVA) and antioxidant essential oils. The effect of the bilayer active film on the quality and shelf-life of mutton was investigated. PVA laminated material was considered to improve the barrier capacity, while essential oils incorporated into EVA laminated material conferred antioxidant and antimicrobial activity. The effect of the addition of essential oils on the film by mechanical properties, oxygen permeability, scanning electron microscopy (SEM) image, Fourier transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) was investigated. Releasing of active compound into mutton and antioxidant activity was investigated to evaluate the films. The antibacterial effects of bilayer active films were subsequently evaluated based on the antibacterial properties of active film and Total viable counts (TVC) of mutton. Microbial community structure in the mutton of different packaging was analyzed by Illumina MiSeq sequencing. Based on total volatile basic nitrogen (TVB-N), the shelf life of mutton was tested. The results showed that the active compound improved flexibility and ductility of active PVA/EVA films. The results also showed a high release of OEO (21.99 mg/kg) and TTO (17.96 mg/kg) as well as high antioxidant and antimicrobial efficiency of PVA/EVA films with essential oils. High-throughput sequencing has shown that the addition of OEO and TTO can reduce the type of dominant bacteria, reducing Acinetobacter by 15.8% and 15.55%, respectively. The release test of active compounds into the mutton showed that the higher contents of the active compounds released, the more microbial proliferation limited, thereby it effectively retarded the increase of TVB-N, which extended the shelf life of mutton by 5–6 days. • The bilayer active packaging film based on PVA/EVA copolymer was prepared by using essential oil as a preservative. • The release of active compound into food simulants and mutton was explored to evaluate the films. • The microbial community structure in the mutton of different packaging was analyzed through Illumina MiSeq sequencing. • Active films extended the shelf life of mutton. [ABSTRACT FROM AUTHOR]

• A two-stage fluidized bed was used for secondary conversion of MTA products. • Secondary conversion of light hydrocarbon increased the aromatics yield. • Reaction paths of secondary conversion depended on temperature and catalyst acidity. • Regional functionalization of fluidized bed reactor was proposed for process intensification of MTA. Methanol to aromatics (MTA) following dual cycles concept unavoidably produced considerable amounts of olefinic intermediates and paraffinic by-products. Their formation and further conversion were vital to improving aromatics production. In this study, a two-stage fluid bed packed with fluid Zn/ZSM-5 catalyst in each stage was used to investigate the MTA reaction at 470 °C in the first stage and the secondary conversion of MTA primary products at temperatures from 270 °C to 550 °C in the second stage with time on stream. During the MTA reaction, the decrease of catalyst acidity was beneficial to controlling hydrogen transfer, thus blocking propane formation. During the secondary conversion of MTA products, at temperatures below 390 °C, the alkylation and hydrogen transfer reactions dominated and thus olefins were converted into more alkylbenzene as well as the undesired propane and butane. As the temperature increased from 430 °C to 550 °C, the aromatization of light hydrocarbon and the dealkylation of alkylbenzene were facilitated, producing more benzene and toluene but increasing methane and ethane yields. Meanwhile, the dehydrogenation and cracking of propane and butane were favored by high temperature and strong acidity so that the yields of ethene and propene increased. It was clarified that the characteristics of secondary conversion of MTA products varied and depended on reaction temperature and catalyst acidity. Based on these findings, the concept of regional functionalization of fluidized bed reactor was proposed for intensification of MTA process based on the reconfiguration of the temperature and acidity of catalyst stream during the fluidized bed reaction-regeneration cycle. [ABSTRACT FROM AUTHOR]

• Techno-economic analysis of the synthetic route of syngas to aromatics is reported. • Systematic models for direct and indirect route are built based on the Aspen Plus. • Energy consumption and economic aspects are both seriously CO-conversion dependent. • Product selectivity exhibits insignificant effect on the total installation cost and heat utility. • Direct STA route shows advantages at the conversion of CO above 66%–72%, without considering the formation of CO 2. Direct conversion of syngas-to-aromatics (STA) is an increasing vital catalytic field that still contains much uncertainty. For the first time, we report the process simulation of STA via direct routes and indirect STA (syngas first to produce methanol, then methanol being converted into aromatics). The conversion of CO was selected as the sensitivity indicator for the evaluation of energy consumption and economic aspects. A low conversion of CO resulted in a low yield (and low partial pressure) of aromatics and an increasing difficulty in separating them from unreacted syngas and light hydrocarbons. The associated increased investment and operational costs were analyzed quantitatively. Direct STA shows obvious advantages in operational cost savings and in construction costs when the conversion of CO was higher than 66–72% when compared with the indirect STA route. The simulation results provide new insights into the upper limits of the process of developing catalysts. [ABSTRACT FROM AUTHOR]

Tree height is an essential indicator in forestry research. This indicator is difficult to measure directly, as well as wind disturbance adds to the measurement difficulty. Therefore, tree height measurement has always been an issue that experts and scholars strive to improve. We propose a tree height measurement method based on tree fisheye images to improve the accuracy of tree height measurements. Our aim is to extract tree height extreme points in fisheye images by proposing an improved lightweight target detection network YOLOX-tiny. We added CBAM attention mechanism, transfer learning, and data enhancement methods to improve the recall rate, F1 score, AP, and other indicators of YOLOX-tiny. This study improves the detection performance of YOLOX-tiny. The use of deep learning can improve measurement efficiency while ensuring measurement accuracy and stability. The results showed that the highest relative error of tree measurements was 4.06% and the average relative error was 1.62%. The analysis showed that the method performed better at all stages than in previous studies. [ABSTRACT FROM AUTHOR]

This article investigates robust multiple fault detection (FD) and fault estimation (FE) schemes, based on adaptive finite‐time observer (AFTO), applied to nonlinear systems with disturbances, actuator faults, and sensor faults. The AFTO is designed, and a parameter adaptive law is constructed to continuously optimize the residual based performance function to improve the AFTO robustness. The schemes are able to simultaneously detect and estimate unknown states, disturbances, and faults. The AFTO's design, finite‐time convergence and stability conditions are guaranteed in terms of linear matrix inequalities. Finally, simulation results, based on two typical practical systems, are given to illustrate the effectiveness of the proposed approaches. The simulation results also show that the designed AFTO can offer faster convergence speed, higher estimation accuracy, and stronger robustness than conventional H∞$$ {H}_{\infty } $$ observer and sliding mode observer. [ABSTRACT FROM AUTHOR]

As an emerging energy carrier, hydrogen presents a potential opportunity to increase the flexibility and resiliency of the integrated power and transportation system having ultrahigh penetration of renewable generation. This article studies a conceptual integrated energy-mobility system (IEMS) based on renewable-to-hydrogen stations (RHSs) and tank truck fleets. In an RHS, the renewables power the grid while also charge a hydrogen energy storage unit that can perform power-to-hydrogen (P2H) and hydrogen-to-power (H2P) operations. Besides, using tank truck fleets, the RHS will distribute its surplus hydrogen products to local consumers, e.g., refueling stations serving hydrogen fuel cell vehicles. The operation framework of the IEMS is analyzed. And some preprocessing technologies are developed to reduce modeling complexity. Then, a joint optimal scheduling model, involving renewable generationcontract, P2H, and H2P of the RHS, hydrogen product demands of the local consumers, and vehicle routing problem (VRP) of the truck fleets, is established. Afterwards, the formulated problem is solved by a heuristic method based on the exhaustive search and genetic algorithm. Numerical results verify the effectiveness of the joint optimal scheduling model and illustrate that the IEMS has the potentials to promote hydrogen-integrated transportation and power systems. [ABSTRACT FROM AUTHOR]

Cardiac diffusion tensor imaging (cDTI) is a promising and noninvasive magnetic resonance imaging (MRI) technique for assessing myocardial fiber microstructure. However, its clinical application is hampered by lengthy scanning and susceptibility to motion artifacts. This study proposes a cDTI reconstruction model (OSDTI), which leverages octave convolution (OctConv) and Swin Transformer to reconstruct diffusion‐weighted (DW) images from undersampled k‐space data. Our model capitalizes on the strengths of both OctConv and Swin Transformers. Specifically, the OctConv module excels at capturing intricate details and texture information within DW images, while the residual‐connected Swin Transformer module facilitates information retention across various feature extraction stages, thereby enhancing overall image comprehension and reconstruction accuracy. The evaluation of OSDTI using a human ex vivo heart dataset robustly validated the generalization ability of the model. Comparative analyze against existing deep‐learning methods demonstrated OSDTI's superior performance in both DW image quality and diffusion tensor metrics. [ABSTRACT FROM AUTHOR]

To enhance the friction and wear performance of cemented carbide, textured microholes were machined on micro Electron Discharge Machining (EDM) on the tool rake face, and Calcium Fluoride (CaF2) powders were burnished into the microholes. The friction and wear characteristics of the microhole-textured tool filled with CaF2 were investigated using sliding friction tests and dry cutting tests. Results exhibited that the working temperature could affect the tribological performance of the microhole-textured tool filled with CaF2 due to the temperature-sensitive nature of CaF2. There is no obvious lubrication effect for the textured tool filled with CaF2 at room temperature, while it was shown to be more effective in improving tribological property at a cutting speed of higher than 100 m/min with a corresponding to cutting temperature of 450 °C. The possible mechanisms for the microhole-textured tool filled with CaF2 were discussed and established. [ABSTRACT FROM AUTHOR]

In order to enhance the tribological performance of YT14 carbide, pure Zr coating was deposited on the substrate surface using a multi-arc ion plating method. The surface topography, adhesion strength, thickness, and micro-hardness of the Zr coating were tested. Dry sliding friction experiments against a 40Cr hardened steel ring were conducted with Zr-coated carbides and traditional ones. The average coefficients of friction were measured and compared. The wear characteristics of the samples were examined by scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDX). The test results indicated that the Zr coating deposited on the carbide surface exhibited excellent adhesive strength and lower hardness. The average friction coefficient of Zr coated carbide decreased by 20%–30% in comparison with that of the uncoated one. The Zr coated carbide could reduce the adhesive wear compared with the uncoated one, and the main tribological degradation mechanisms of the coating were abrasive wear, coating flaking and delamination. [ABSTRACT FROM AUTHOR]

Diffusion tensor imaging (DTI) is known to suffer from long acquisition time, which greatly limits its practical and clinical use. Undersampling of k-space data provides an effective way to reduce the amount of data to acquire while maintaining image quality. Radial undersampling is one of the most popular non-Cartesian k-space sampling schemes, since it has relatively lower sensitivity to motion than Cartesian trajectories, and artifacts from linear reconstruction are more noise-like. Therefore, radial imaging is a promising strategy of undersampling to accelerate acquisitions. The purpose of this study is to investigate various radial sampling schemes as well as reconstructions using compressed sensing (CS). In particular, we propose two randomly perturbed radial undersampling schemes: golden-angle and random angle. The proposed methods are compared with existing radial undersampling methods, including uniformity-angle, randomly perturbed uniformity-angle, golden-angle, and random angle. The results on both simulated and real human cardiac diffusion weighted (DW) images show that, for the same amount of k-space data, randomly sampling around a random radial line results in better reconstruction quality for DTI indices, such as fractional anisotropy (FA), mean diffusivities (MD), and that the randomly perturbed golden-angle undersampling yields the best results for cardiac CS-DTI image reconstruction. [ABSTRACT FROM AUTHOR]

Normalized cross-correlation (NCC) is fast to compute but its accuracy is low. In this paper, we propose a fast, highly accurate NCC image matching algorithm. First, a wavelet pyramid is constructed to reduce feature point searching and matching times. Then, an NCC image matching algorithm is used to acquire the coarse matching points in the original image. Next, an improved iterative relaxation algorithm is used to remove false matching points, and an adaptive winner-takes-all strategy is introduced to improve the algorithm's iteration speed and obtain more one-to-one matching points. Our experimental results show that the proposed algorithm can improve not only matching speed, but also matching accuracy. [ABSTRACT FROM AUTHOR]

• A three-stage fluidized bed technology was proposed for high-yield aromatics production from methanol. • Light hydrocarbons aromatization in the second stage significantly raised aromatics yield. • Coupling olefins alkylation in the third stage contributed more alkylbenzenes. • Gross yield of aromatics kept high and was independent of the deactivation of catalysts in the first and second stages. We propose a temperature-shifting three-stage fluidized bed reactor technology for the consecutive conversion of methanol and its intermediate products into aromatics. The first stage served the aromatization of methanol. The second stage served the aromatization of the intermediates of light paraffins and olefins. The third stage served the alkylation of residual olefins. The yield of the aromatics was relatively stable within 12 h in the exit of third stage and was 6–12% higher than that in the exit of first stage. The increased yield of aromatics was attributed to the effective transformation of intermediate products (C 2 -C 5 hydrocarbons). The final alkenes/alkanes ratio dropped to only 0.03. The time-dependent yields of aromatics, olefins and paraffins were analyzed in detail based on the information of coke at different stages. The results provide insight into the consecutive conversion network of methanol into aromatics. [ABSTRACT FROM AUTHOR]

Considering that the 3D pulse-coupled neural network (3D-PCNN) model has the deficiency of high parameter complexity and low accuracy in color image segmentation, swarm intelligence optimization algorithm is adopted to optimize the image segmentation process. In this paper, whale optimization algorithm (WOA) is adopted to optimize the 3D-PCNN model parameters E and β. The improved product cross entropy (IPCE) is chosen as the fitness function of optimization algorithm. WOA algorithm is used to find the minimum fitness function, and the corresponding optimal parameters are obtained. Through the study of image segmentation in the image segmentation library of University of Berkeley and the actual plant canopy image, the maximum entropy value and the Tsallis entropy value are compared and analyzed. Experimental results illustrate that the proposed algorithm can obtain more accurate image segmentation effect and higher segmentation rate. [ABSTRACT FROM AUTHOR]