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A comprehensive understanding of the physico-mechanical behavior of rocks in hot dry rock (HDR) reservoir after different stimulation treatments is essential for the safe and effective exploitation of geothermal energy. In this study, the physico-mechanical properties of high-temperature granite (25–600 °C) subjected to slow cooling, water cooling, and liquid nitrogen (LN2) cooling were experimentally investigated, and the damage evolution and damage mechanism of the rock were discussed from the macro- and microscopic perspectives. According to the experimental results, the increase in thermal treatment temperature aggravates the deterioration of the physico-mechanical properties of granite specimens. It is found that 400 °C is the threshold temperature of the tested granite, after which the physico-mechanical properties of the rock present more prominent changes. Since LN2 can induce a more intense thermal shock within rocks, it has the most significant damage to the specimens compared with other two cooling methods, especially at a higher thermal treatment temperature. Acoustic emission (AE) monitoring can well reflect the failure process and the associated microcrack behavior of the specimens during loading. The results of thin slice analysis indicate that the generation and extension of microcracks are responsible for the macro-properties degradation of rocks. Both grain boundary and intra-grain microcracks are more common near quartz boundaries and inside quartz grains. The results in this study would shed light on performing HDR reservoir stimulations assisted with cryogenic LN2. [ABSTRACT FROM AUTHOR]

• A new Co-based coating with excellent thermal-fatigue resistance was prepared. • The martensitic transformation only occurred in single cladding during TF process. • Boundaries of grain and γ/ε phase acted as the weak region for the crack initiation. The Co-based coating by laser deposition could improve the thermal-fatigue (TF) resistance of hot working dies but the effect of technology on properties remained to be studied further. This work investigated the influence of the microstructure and γ/ε transformation on the TF life of the Co-based coating of the AISI H13 hot work die steel. Direct laser deposition (DLD) layers were prepared on the steel surface using modified Co-based alloys, which increased the contents of Cr, W, and Ni. The single and duplex layers were made under precise conditions, and the difference in the TF test life was significant. Meanwhile, the hardness of the duplex layer coating was much higher than that of the single one in the TF process consistently. Various detection methods were adopted to characterize the Co-based coating structures and crack propagation during the TF test. The microstructure of the two deposition coatings uniformly included the γ-Co phase and M 23 C 6 crystalline phase. Moreover, after the TF experiment, the γ/ε transformation only occurred in the single layer as observed by transmission electron microscopy and electron backscattered diffraction. This indicated that the dilution of the base metal element distribution played a key role in reducing the stability of the γ-Co phase, which resulted in relatively low stacking fault (SF) energies, micro-hardness, a high fraction of the precipitate, and an early crack generation of the coating. This research was beneficial for understanding the microstructure, grain growth, γ/ε transformation, and crack propagation behavior in the DLD layers and TF test. [ABSTRACT FROM AUTHOR]

• LaNi 1- x Pt x O 3 /SiO 2 were prepared by a facile method of citrate acid complexation combined with impregnation. • Pt/LaNiO 3 loaded on SiO 2 was obtained by reducing LaNi 1- x Pt x O 3 /SiO 2. • Pt atoms were highly dispersed on a support by using a perovskite-type oxide as the precursor. • Pt/LaNiO 3 /SiO 2 showed excellent activity and stability for CO oxidation. A new facile method for preparing highly dispersed precious metal catalysts was proposed in this work. Highly dispersed Pt supported on LaNiO 3 /SiO 2 were prepared by using LaNi 1- x Pt x O 3 perovskite as precursors. The catalytic performances of CO oxidation over the prepared catalytsts were investigated. The structural features of the catalysts were characterized by N 2 adsorption-desorption, XRD, H 2 -TPR, TEM, EXAFS, CO-TPD and O 2 -TPD techniques. The result indicated that nanocrystalline of LaNi 1- x Pt x O 3 was supported on SiO 2. Reducing LaNi 1- x Pt x O 3 /SiO 2 could make Pt from the interior of the perovskite crystal lattice onto the surface and then form highly dispersed Pt on the support of LaNiO 3 /SiO 2. As the platinum content was 0.5% or less, platinum atoms could distribute highly even maybe in single atoms. The catalytic test revealed that LaNi 0.95 Pt 0.05 O 3 /SiO 2 exhibited a significant activity and stability for CO oxidation, as well as excellent performance in the presence of both 15 vol.% H 2 O and 12.5 vol.% CO 2. It has been demonstrated that the highly dispersed Pt, the easy reducibility, and sufficient surface oxygen species were responsible for the high catalytic activity of LaNi 0.95 Pt 0.05 O 3 /SiO 2 catalyst. [ABSTRACT FROM AUTHOR]

• Effective stress-strain relationship for the grouted sleeve connections is presented. • Transverse pressure influence coefficient exerted by the sleeve coupler was modeled. • The performance of prefabricated piers under cyclic loading was tested. • The proposed model was verified by using the connection test and pier test. • The proposed model can be implemented in 1D, 2D, and 3D finite element analysis. This paper describes the development of an effective stress-strain relationship model for grouted sleeve connections. The transverse pressure influence has been calibrated by using the local bond stress-slip experiment including the effect of the initial construction error of the reinforcing bar. Then, the proposed effective stress-strain model was presented by solving the governing equation of the bond stress-slip behavior for the long-bonded grouted sleeve connection. The grouted sleeve connection can be equivalent to a reinforcing bar with a higher elastic modulus and yielding strength. The equivalent elastic modulus decreases with the increase in the initial construction error, and can be calculated by using the proposed model. The experiments on the long-bonded grouted sleeve connection and prefabricated concrete piers were carried out to verify the proposed model. The tested effective stress-strain relationship of the grouted sleeve connection, the maximum slip of the reinforcing bar embedded in this connection, and the strain distribution of the sleeve coupler were successfully predicted. Moreover, the performance of prefabricated concrete piers under cyclic loading was successfully simulated by using the proposed model. [ABSTRACT FROM AUTHOR]

In order to integrally manufacture the large TC4 titanium alloy part, an electrically-assisted incremental forming process is cleverly proposed to solve the traditional hot forming disadvantages of expensive heating furnaces and long cycle period. The two-step simulation method including thermal-electricity coupling simulation and thermo-mechanical coupling simulation was selected to predict the temperature variations and the sheet deformation behaviors. The electrically-assisted incremental forming experiment of thin TC4 titanium alloy sheet was performed. The highest prediction error is 6% for springback angles. The thrice forming at 10.9 A/mm2 satisfies the precision requirement of the designed part. Therefore, the two-step simulation method can effectively calculate the electrically-assisted incremental process. The electrically-assisted incremental forming technique is very promising for the integral producing large titanium alloy part. [ABSTRACT FROM AUTHOR]

A diatomite supported graphene oxide composite (GO@Dt–NH2) was fabricated and explored as a solid-phase extraction adsorbent coupled with high performance liquid chromatography to determine the trace hydroxyl polycyclic aromatic hydrocarbons (2-hydroxy-naphthalene, 2-hydroxy-fluorene, 1-hydroxy-phenanthrene, and 1-hydroxy-pyrene) in urine samples. The fabricated composites were characterized by X-ray powder diffractometry and scanning electron microscopy. GO@Dt–NH2 offered enhanced adsorption affinity towards the analytes compared with the bare diatomite. The amount of graphene oxide and the factors affecting solid-phase extraction were investigated in detail. Under the optimized conditions, the method gave good linearity (0.30–200 ng/mL) and a low detection limit (0.10–0.15 ng/mL) for the hydroxyl polycyclic aromatic hydrocarbons. The average recovery for spiked urine samples with three levels ranged from 90.6% to 100%. The intra-day and inter-day relative standard deviations were in the range of 1.8–6.4% and 2.7–11.8%, respectively. Besides, the GO@Dt–NH2 provided enrichment factors of 18–20 and superior purification ability. The developed method was successfully applied to the determination of hydroxyl polycyclic aromatic hydrocarbons in urine samples from smoking volunteers. [ABSTRACT FROM AUTHOR]

Metasurfaces for beam engineering are usually implemented by using dense-plasmonic or high-contrast dielectric building blocks with deep-subwavelength feature size and strong field confinement. Here, we theoretically and experimentally demonstrate extremely large angle deflection with a very steep phase gradient based on low-contrast () metagratings composed of very sparse building blocks. Only two ridges are included in a 4π variation supercell, which diffracts the normal excitation to desired angles as large as 80° with a theoretical efficiency of more than 80%. Due to the limited beam radius relative to the metasurfaces, the angular distribution of the intensity is broadened with reduced peak intensity. Such metagratings are 3D-printed for 0.14 THz operation. The measured peak intensities are 57% of the theoretical ones due to material loss and fabrication errors. Repeatability, bandwidth and angular sensitivity are systematically studied, and the results pave the way towards using practical THz elements for large-gradient wavefront shaping. [ABSTRACT FROM AUTHOR]

Defects can influence the properties of photocatalysts, and defective ZnO has triggered broad interest and intensive studies for decades. However, the correlation between crystal planes and defects remains unclear. Here, we demonstrate that the (101) plane is superior in producing oxygen vacancies than the (100) plane in rod-like defective ZnO samples. While the optimum intensity of the crystal ratio, (101)/(100), approaches 1, the separation efficiency of electrons–holes is much enhanced. Furthermore, it is found that the (101) plane has stronger spontaneous adsorption and higher dissociation activity of H2O, which is conducive to the spontaneous formation of oxygen vacancies and eventually enhances the separation efficiency of electrons–holes. The charge difference also shows that the crystal boundary junctions could cause uneven charge distribution, inducing lattice polarization and boosting the charge separation of defective ZnO, which is helpful for improving the photocatalytic activities. As a new proposed mechanism, the relationship between defect engineering and crystal surface could provide inspiration for the design of special nanomaterials for the environment purification and energy fields. [ABSTRACT FROM AUTHOR]

A MOF-based sacrificial template strategy is demonstrated to construct novel Mo-doped Co(OH) 2 hierarchical nanotubes organized by cross-linked porous nanosheets with the optimized electronic structure of more highly oxidative Co3+ species, which exhibits active and stable electrocatalytic activity for overall water splitting. • The Mo-doped Co(OH) 2 HNTs organized by cross-linked porous nanosheets are prepared. • Electronic structures with highly oxidative Co3+ species can be modified by Mo doping. • The low overpotentials of 218 mV and 125 mV for OER and HER are obtained. • Mo-Co(OH) 2 HNTs exhibit high electrocatalytic activity for overall water splitting. Designing hierarchical nanostructures of earth-abundant electrocatalysts for enhanced overall water splitting performance is of great significance. Herein, Mo-doped Co(OH) 2 hierarchical nanotubes (Mo-Co(OH) 2 HNTs) assembled by cross-linked porous nanosheets are designed and synthesized through a sacrificial template strategy. Benefiting from the hierarchical structures based on porous nanosheets with void interior as well as modified electronic structure of higher intensity of Co3+ species by Mo6+ doping, the Mo-Co(OH) 2 HNTs demonstrate superior electrocatalytic performance, achieving an current density of 10 mA cm−2 at the low overpotentials of 218 mV and 125 mV for oxygen and hydrogen evolution reactions, respectively. Furthermore, an overall water splitting cell was assembled with the Mo-Co(OH) 2 electrocatalyst as both the anode and cathode materials, which exhibits a driving voltage of as low as 1.62 V. The facile strategy presented in this work can be extended to the construction of various hollow/porous nanostructures with effective heteroatom doping to achieve low-cost, bifunctional and high-performance electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

Cocatalysts play an important role in converting solar energy into chemical energy for photocatalytic water splitting. Herein, a versatile and efficient cocatalyst based on amorphous Co species (a-Co-E) is synthesized through thermal treatment of a Co–ethylene diamine tetraacetic acid complex in air at 300 °C. Various Bi-based semiconductors loaded with the a-Co-E cocatalyst exhibit an impressively higher photocatalytic O2 evolution rate than their CoOx-loaded counterparts. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging techniques are widely used for rapid, efficient, and non-destructive identification of wheat varieties. However, the interference of noise in hyperspectral images and the underutilization of spatial information by most methods are two challenging issues in identifying wheat varieties. In this paper, we present a new approach called Cost-sensitive K-Nearest Neighbor using Hyperspectral imaging (CSKNN) to address these issues. First, we fuse 128 bands acquired by hyperspectral imaging equipment to obtain hyperspectral images of wheat grains, and employ a central regionalization strategy to extract the region of interest. We then use a smoothing denoising strategy to remove noise from the hyperspectral images and improve the saliency of the object grains. Furthermore, we consider the characteristics of different bands and use linear discriminant analysis to compress features, reducing intra-class differences and increasing inter-class differences. Finally, we propose a Cost-sensitive KNN for training and testing of wheat varieties. Our experiments on different strains and varieties of wheat datasets in the same region show that our CSKNN achieves high classification accuracies of 98.09% and 97.45%, outperforming state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Cover Feature: Covalent Organic Framework-Supported Metallocene for Ethylene Polymerization (Chem. Eur. J. 54/2023) Covalent organic frameworks, ethylene polymerization, heterogenous polymerization, polyolefins, supported metallocenes Keywords: covalent organic frameworks; ethylene polymerization; heterogenous polymerization; polyolefins; supported metallocenes EN covalent organic frameworks ethylene polymerization heterogenous polymerization polyolefins supported metallocenes 1 1 1 09/29/23 20230926 NES 230926 B Covalent organic framework b (COF) particles with hydroxy groups and well-defined micropores have been synthesized and used as novel carriers to load a metallocene catalyst - Cp SB 2 sb ZrCl SB 2 sb . [Extracted from the article]

Hyperspectral image (HSI) based methods are widely used in identifying seeds varieties with high accuracy. However, the excessive spectral bands in HSI may contain redundant information and degrade the model performance. To address this challenge, we propose a novel feature extraction method called low rank tensor approximation (LRTA). Unlike traditional methods, LRTA extracts joint discriminative information of all wheat seeds from hyperspectral images in a 3-order tensor form, preserving intrinsic information. Our model has three key steps: extracting the region of interest from hyperspectral images and presenting average spectral information in tensor form, using LRTA to extract jointly discriminative information, and feeding this information into a classifier to identify seeds varieties. Experiments on our proposed dataset show that the proposed method has 4% improved to the conventional methods on average. Our method shows promise for improving the accuracy of seeds identification while reducing the dimensionality of HSI. [ABSTRACT FROM AUTHOR]

• Strain field evolution and crack coalescence mechanism of composite strength rock-like specimens with sawtooth interface were investigated. • As the inclination of the interface increases, the peak strength of the specimen first decreases and then increases, reaching the maximum value of 28.29 MPa at the 90° interface. • The failure mode of specimen is greatly related to the strength of rock layer and the inclination of the interface. • The failure modes of the specimen are classified as single weak rock layer failure, oblique failure through rock layer interface, slip failure along the interface and axisymmetric failure along the interface. • The sawtooth parameters have an important influence on the type and location of cracks developed along the interface. The mechanical behaviors of composite rock masses containing a complex interface widely distributed in nature are significantly different from those of monolithic rock masses. The objective of this study is to perform a series of uniaxial compression tests to study the influence of sawtooth interface parameters on the fracture behavior of rock-like composite specimens. Meantimes, the acoustic emission (AE) and digital image correlation (DIC) technique were used to classify damage stages and record strain field evolution, respectively. The results of this study demonstrate that stress–strain curves of composite rock-like specimens with different sawtooth interfaces display characteristics of plastic failure, friction failure characteristics and two different brittle failure characteristics in the post-peak phase. The peak strength of the specimen first decreases and then increases as the inclination of the interface increases, achieving the maximum value of 28.29 MPa at the inclined interface of 90°. The strain concentration zone is mainly generated and expanded around the interface. The parameters of the sawtooth have a significant influence on the type and location of cracks developed along the interface. In addition, there is a strong relationship between the mode of failure of the specimen and the strength of the rock layer and the inclination of the interface. According to the relative positional relationship between the coalescence path of the specimen and the interface, the failure modes of the specimen are classified as single weak rock layer failure (S-AB-0, S-AB-15), oblique failure through rock layer interface (S-AB-30, S-AB-45), slip failure along the interface (S-AB-60, S-AB-75) and axisymmetric failure along the interface (S-AB-90). This result is of great importance for a thorough understanding of the crack coalescence mechanism and strain field evolution of rock-like composite specimens. [ABSTRACT FROM AUTHOR]

The issue of dynamic event-triggered trajectory tracking control of autonomous underwater vehicles (AUVs) in the Trans-Atlantic Geotraverse (TAG) active mound is addressed. Concretely, a novel adaptive event-triggered disturbance observer along with auxiliary functions is constructed to handle with actuator faults and ocean current in the TAG active mound. By using rotation matrices, a new tracking error system involving position and attitude is developed such that potential singularities caused by the large pitch will be sufficiently avoided. By deep combination with model parameters, a sliding mode manifold based on additional velocity errors is established to promote robustness and convergence. Following the detailed analysis, sufficient conditions for the input-to-state practical stability in mean square are given to ensure the tracking performance. An adaptive dynamic event-trigger method is applied to reduce the communication frequency between the embedded PC module and actuators. Finally, the applications of an AUV tracking system in the near-bottom hydrothermal mound are carried out to verify the efficiency of the presented method. • A event-triggered disturbance observer with auxiliary functions is constructed. • A sliding mode manifold with additional velocity errors is established. • The AUV's rotation-matrix dynamic event-triggered tracking sysytem is verified. • With the modeling trajectory, the impacts of the TAG mound is considered. [ABSTRACT FROM AUTHOR]

• Phytoremediation plant waste was disposed via pyrolysis. • PTMs were more sensitive to leaching time in low-temperature biochar. • High-temperature pyrolysis was beneficial for PTMs and biochar stabilization. Thermal conversion of phytoremediation plant waste into biochar was performed as a safe approach for organic waste management. In this work, a promising phytoremediation plant― Silphium perfoliatum L. was pyrolyzed for biochar production at 350, 550 and 750 °C. The long-term leaching risk of potentially toxic metals (PTMs) in the derived biochars and the oxidation resistance of the biochars were investigated. The results showed that PTMs in the biochar could transform into more stable and less toxic forms with the elevated pyrolysis temperature. PTMs leaching behavior in the 350 °C biochar was considerably sensitive to the leaching while that in the 750 °C biochar was not affected. The biochar produced at a higher temperature possessed a greater oxidation resistance with little amount of C loss, and the stronger oxidation resistance would prevent the release of metals bound to the organic matter. The findings of this study demonstrated that high-temperature pyrolysis was able to reduce the potential risk of PTMs and ensure carbon stability. [ABSTRACT FROM AUTHOR]

Abstract: Phytoremediation is regarded as one of the most cost-effective and environmentally friendly strategies for potentially toxic metals (PTMs) contaminated soil remediation. However, uncertainties still existed about the contribution of foliar litter on metal accumulation and mobility in phytoremediation sites. Thus, in this study, fallen leaves, decomposed leaves, and soils at different depths (i.e., 0–5 and 5–10 cm) were collected from a phytoremediation site near a Zn smelter factory. Metals content and mobility were evaluated. Results indicated that upper-layer soils (0–5 cm) were higher in the electrical conductivity (EC) and soil organic matter (SOM) content than the deeper-layer soils (5–10 cm). However, the pH was relatively lower in the upper-layer soils. Fallen leaves were sources of metals in the phytoremediation site, and significantly high amounts of Cd (16.08 ± 0.21 mg kg−1) and Zn (1130.30 ± 60.10 mg kg−1) were found in the decomposed leaves. Metals in the upper-layer soils demonstrated higher accumulation and mobility than the deeper-layer soils. Moreover, the accumulated metals in leaves would gradually return to the soil as the contents of extractable metals increased with the rising decomposition degree of leaves (i.e., cold-water extraction < 80 °C hot water extraction < 1 M HCl extraction). Results from this research are helpful for the guidance of phytoremediation site management. Graphical abstract Image 1008210 Highlights • Effects of foliar litters on PTMs circulation in phytoremediation sites were firstly investigated. • Release of metals from plant leaves elevated metal contents and their mobility in soils. • Metal contents reduced as decomposed leaves > upper-layer soils > deep-layer soils. • Removal of plant leaves is necessary for the management of phytoremediation site. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) is a crucial reaction for various energy conversion and storage devices, but the sluggish kinetics and the usage of noble metals greatly restrict its practical device applications. In this work, a well-designed high-performance catalyst for ORR was synthesized via a facile one-step Co-MOF carbonization method, in which Co-MOF was prepared using the cobalt acetate tetrahydrate and 2,2′-bipyridyl-5,5′-dicarboxylic acid (H2bpydc) as the only raw materials and H2bpydc as the favorable carbon and nitrogen source for in situ nitrogen doping and metallic cobalt reduction. The resultant 3D mesoporous carbon foam catalyst with embedded Co nanoparticles (CoN-CF) is enriched with nitrogen, which exhibits high specific surface area and abundant N-doping active sites for catalytic ORR. In particular, the optimized CoN-CF-700 sample displays the best catalytic performances including onset potential of 0.94 V, half-wave potential of 0.85 V, long-term durability and superior resistance to methanol poisoning. The demonstrated synthetic strategy provides a new insight into easy-synthesis and high-economy routes for metal-N-C catalysts and a deeper understanding of the effects of microstructures on catalytic mechanisms. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new and mass-produced strategy was used to synthesize Ni 2 P/Fe 2 P/NF 3D electrode. • The Ni 2 P/Fe 2 P/NF electrode exhibits superior activity toward both UOR and HER. • Only a cell voltage of 1.47 V is required to the current density of 10 mA cm−2. • The facile synthetic strategy provides a prospect for industrializable production. Abstract Urea electrolysis is regarded as an alternative energy-saving hydrogen production technique to replace the conventional water splitting method due to the predicted lower thermodynamic potential. Herein, we demonstrate a robust and mass-produced strategy to in-situ grow Ni 2 P/Fe 2 P nanohybrids on Ni foam (Ni 2 P/Fe 2 P/NF) as an advanced electrode for overall urea electrolysis via a 30 s manual shaking reaction of FeCl 3 ·6H 2 O, K 3 [Fe(CN) 6 ] and pre-treated NF, followed by a facile phosphorization treatment. The as-prepared Ni 2 P/Fe 2 P/NF electrode exhibits high activity for the HER at 115 mV and UOR at 1.36 V with the current density of 10 mA cm−2, and only a cell voltage of 1.47 V is required to deliver the current density of 10 mA cm−2. This work reveals a promising industrializable pathway to develop non-noble materials as bifunctional catalysts. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel and high-efficiency photocatalyst based on CCO/BWO nanocomposite was firstly synthesized. • CCO/BWO nanocomposite was prepared via a facile hydrothermal method. • CCO/BWO nanocomposite exhibits extraordinarily high photoactivity towards O 2 evolution without additional of any cocatalyst. Abstract The practical application of photocatalytic water splitting is essentially limited by the slow kinetic nature of the water oxidation process. Therefore, it is highly desirable but challenging to explore a low-cost and high-efficiency water oxidation catalyst for the aim of commercialization and industrialization. We herein report the first-time synthesis of a novel and high-efficiency visible-light-driven photocatalyst composed of flower-like Co(CO 3) 0.5 (OH)·0.11H 2 O (CCO) nanowires and Bi 2 WO 6 (BWO) nanosheets, i.e. CCO/BWO nanocomposite, via a facile hydrothermal method. Without utilizing any additional cocatalyst, the composite of CCO/BWO in 30% weight ratio exhibits extraordinarily high photoactivity and photostability towards O 2 evolution, achieving an average O 2 generation rate of 953 µmol h−1 g−1 under visible-light irradiation (λ > 420 nm). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Surface charge is the most important for anionic surfactant affecting sorption. • Concentration is the most important for cationic surfactant affecting sorption. • Dispersion status is the most important for nonionic surfactant affecting sorption. • Sorption isotherms presence of surfactants fitted well with Toth model. • Sorption coefficient was linearly correlated with the characterization parameters. Abstract The production of carbon nanotubes (CNTs) increased rapidly due to the superior properties and was suggested to be the potential sorbents for environmental remediation. CNTs tend to form aggregates, thus CNTs dispersion was commonly produced by sonication with surfactant in industry for better application. In the present study, a novel passive sampling method was used to systematically study sorption of triclosan to CNTs dispersion to give a better understanding on their interactions especially with the presence of surface-active substances. With the increase of anionic surfactant concentration (SDBS or SDS), sorption of triclosan was gradually suppressed. CNTs dispersed by nonionic surfactant TX-100 increased or decreased sorption at different TX-100 and triclosan concentration. Little amount of cationic surfactant CTAB(1 mg/L) could sharply decrease triclosan sorption to CNTs but with larger CTAB concentration, sorption was continually increased. Sorption isotherms of triclosan to CNTs dispersion with 40 mg/L and 100 mg/L surfactant fitted well with Toth model show the existence of double competition in the sorption process. Different from the adsorption mechanism of previously aggregated CNTs and compounds. Sorption data combined with comprehensive characterization of CNTs dispersion and theoretical analysis, three effects referring to charge, dispersion and competition were proposed. Sorption coefficient was linearly correlated with the characterization parameters. Surface charge, dispersion status and surfactant concentration play the important role on triclosan sorption in CNTs dispersion in the presence of anionic, cationic and nonionic surfactant, respectively. The results provide basic supports on application of CNTs in remediation area and exploring the fate of both CNTs dispersion and pollutants. [ABSTRACT FROM AUTHOR]

Abstract Metal ion doping has been regarded as an effective strategy to improve photocatalytic activity of pristine photocatalysts for rapid charge transfer and separation effects achieved by doping induced defect states. We herein report the fabrication of uniform one-dimensional (1D) Sn4+-doped BiFeO 3 (Sn-BFO) nanofibers (NFs) by a facile electrospinning technique with subsequent annealing treatment. Benefiting from metal ion doping and the unique 1D structure, the as-prepared Sn-BFO NF catalyst exhibits significantly enhanced photocatalytic performance on O 2 evolution as well as improved photostability under visible-light illumination. Revealed by experimental investigation as well as density functional theory (DFT) calculation, the doped Sn atoms were incorporated into the BFO lattice and the band structure of BFO was effectively modified and the defect-related energy levels were produced, which leads to the boosted light absorption and improved charge transfer and separation efficiency. Additionally, an optimal Sn4+ doping percentage of 1.0% was discovered to achieve an average O 2 evolution rate of 516.4 μmol h−1 g−1, nearly two times as much as the non-doped BFO samples. Graphical abstract Image 1 Highlights • A facile electrospinning technique together with subsequent thermal treatment was used to synthesize 1D Sn-BFO PNFs. • 1D Sn-BFO PNFs were evaluated for photocatalytic water oxidation. • The efficient charge transfer induced by the incorporation of Sn into BFO lattice. • The Sn-BFO-1.0% PNFs exhibit the highest photocatalytic O 2 evolution rate. [ABSTRACT FROM AUTHOR]

• Based on data collected on our cannulation simulator, the relationship between process metrics and outcome metrics for this task is explored. • The above modeling is undertaken assuming that most of the process metrics and the outcome metric are on a continuum (versus discrete values), allowing for fine-grained skill assessment. • From the machine learning-based models, we seek to identify the most salient process metrics that impact outcomes for cannulation skill improvement. This knowledge could be used to develop personalized training strategies for skill progression over time Background and Objectives : The quality of healthcare delivery depends directly on the skills of clinicians. For patients on hemodialysis, medical errors or injuries caused during cannulation can lead to adverse outcomes, including potential death. To promote objective skill assessment and effective training, we present a machine learning approach, which utilizes a highly-sensorized cannulation simulator and a set of objective process and outcome metrics. Methods : In this study, 52 clinicians were recruited to perform a set of pre-defined cannulation tasks on the simulator. Based on data collected by sensors during their task performance, the feature space was then constructed based on force, motion, and infrared sensor data. Following this, three machine learning models– support vector machine (SVM), support vector regression (SVR), and elastic net (EN)– were constructed to relate the feature space to objective outcome metrics. Our models utilize classification based on the conventional skill classification labels as well as a new method that represents skill on a continuum. Results : With less than 5% of trials misplaced by two classes, the SVM model was effective in predicting skill based on the feature space. In addition, the SVR model effectively places both skill and outcome on a fine-grained continuum (versus discrete divisions) that is representative of reality. As importantly, the elastic net model enabled the identification of a set of process metrics that highly impact outcomes of the cannulation task, including smoothness of motion, needle angles, and pinch forces. Conclusions : The proposed cannulation simulator, paired with machine learning assessment, demonstrates definite advantages over current cannulation training practices. The methods presented here can be adopted to drastically increase the effectiveness of skill assessment and training, thereby potentially improving clinical outcomes of hemodialysis treatment. [ABSTRACT FROM AUTHOR]

Defect engineering on transition metal dichalcogenides has been regarded as an effective method to improve electrochemical properties in terms of generating active sites and enhancing the intrinsic conductivity. This study reports a new high-performance electrochemical supercapacitor made of reduced CoNi 2 S 4 (r-CoNi 2 S 4 ) nanosheets, which are synthesized via a facile moderate-reduction process. The sulfur-deficient r-CoNi 2 S 4 nanosheets exhibit significantly enhanced conductivity which is induced by abundant sulfur vacancies formed in the reduction reaction. Compared with the pristine CoNi 2 S 4 nanosheets, the r-CoNi 2 S 4 nanosheets are characterized with a higher specific capacity (1117C g −1 at current density of 2 A g −1 ) as well as excellent rate capability and stable cycling performance. First-principle analysis confirms that the sulfur vacancies originating from the reduction lead to improve hybridization between the Ni and Co d states and the S p states close to the fermi level, and consequently enhance conductivity with the CoNi 2 S 4 nanostructure. Moreover, an ultrahigh energy density of 55.4 Wh kg −1 at the power density of 8 kW kg −1 is obtained in an asymmetric supercapacitor configuration, and 80% capacitance of the supercapacitor remains even after 10000 cycles. [ABSTRACT FROM AUTHOR]

Abstract: Bismuth‐doped glasses and fibers with broadband near‐infrared (NIR) emission have garnered much attention on account of their potential applications in new fiber lasers and broadband amplifiers. Yet the realization of high gain from Bi‐doped fibers and highly efficient NIR emission from Bi‐doped glasses are still a stubborn puzzle. The enhancement of Bi NIR emission is normally based on modifying the glass composition and topology, which will change the structure of the glass over a wide range and alter the thermal or mechanical properties of the glass simultaneously, making it more complicated for the designing and fabricating of Bi fibers with good performance. Here, we find that a trace addition of Si3N4 can efficiently enhance the Bi NIR emission without changing the glass structure significantly, right followed by spectral and structural analysis. 27Al NMR measurement reveals that the short‐ to medium‐range order of this glass is unchanged. The EPMA measurement confirms the homogeneity of fabricated glass. The great enhancement and red‐shift under blue light excitation may originate from the conversion of Bi active centers to low valence. Our results indicate that the trace addition of nitride could be a facile and maneuverable way to control the valence of active ions in glasses, which may contribute to improving the performance of photonic glasses. [ABSTRACT FROM AUTHOR]

As a kind of medical service around people, community health care is closely related to peoples lives, and thus it has also been placed higher requirements. In the face of growing community medical needs, the construction and development of community medical Internet of things is imminent. Subsequently, massive multi-type of medical data which contain all kinds of user identity data, various types of vital signs data and other sensitive information are generated. Such a large scale of data in the transmission, storage and access process is facing the risk of data leakage. To effectively protect the privacy information of patients, an infrastructure framework for privacy protection of community medical Internet of things is proposed. It includes transmission protection based on multi-path asymmetric encryption fragment transmission mechanism, storage protection using distributed symmetric encryption cloud storage scheme and access control with identity authentication and dynamic access authorization. Through theoretical analysis and simulation experiments, it is proved that the community medical data can be effectively protected. [ABSTRACT FROM AUTHOR]

Previous studies on the fate of engineered nanoparticles (ENPs) incorporated in paints mainly focused on the release of the particles as affected by a limited number of factors or monitoring their release from natural sources. In this study, the effects of four factors (i.e., weathering duration, water pH, rainfall duration and intensity) were investigated on the release of SiO-ENPs, Ag-ENPs, and TiO-ENPs from paints applied on panels. The static water immersion test showed that the concentrations of studied particles all increased with weathering duration. At low and high pH, SiO-ENPs and Ag-ENPs showed a higher release, while the release of TiO-ENPs was relatively high at low pH. With increased simulated rainfall duration, the concentration released decreased for Si, and the opposite was observed for Ag, while no obvious correlation was noted for Ti. With greater rainfall intensity, there was increasing release of all particles. In total, the releases of Ag-ENPs and TiO-ENPs were extremely low and within the level of 21.32-42.16 μg Land 0.6-2.3 μg L, respectively, while the values for SiO-ENPs were in the range of 7.5-12 mg L. Additionally, microscopic results highlighted that SiO-ENPs were mainly released in the form of agglomerates, and only a small fraction was below 0.1 μm. Considering these influence factors together, conclusions may be made that weathering time and rainfall duration are more important in controlling release than water pH. [ABSTRACT FROM AUTHOR]

Sepsis is a systemic inflammatory response to infection, where sepsis-associated acute kidney injury (AKI) is a common morbid disease with a high morbidity and mortality, and however at present no effective therapy exists. Increasing evidence have shown that mitochondrial damage and inflammatory response are important initiating factors in pathogenesis of septic AKI. Natural flavonoid pectolinarigenin exerted anti-inflammatory properties in previous studies, while its role in septic AKI remains unknown. In the study, pectolinarigenin administration significantly ameliorated the dramatic rise of serum creatinine and blood urea nitrogen in lipopolysaccharide (LPS)- and cecal ligation/puncture (CLP)-induced septic mice, respectively. Consistently, LPS/CLP-induced renal damage as implied by histopathological score and the increased injury markers NGAL and KIM-1, which was attenuated by pectolinarigenin. Meanwhile, LPS/CLP triggered proinflammatory cytokine production and inflammation related proteins in the kidneys. However, pectolinarigenin inhibited renal expression of IL-6, IL-1β, TNF-α, and MCP-1 to improve inflammatory response. Furthermore, pectolinarigenin upregulated Bcl-2 protein expression and suppressed apoptotic protein of BAX and cleaved caspase-3 in the kidneys of CLP-induced septic AKI. Mechanistically, LPS could induce the high expression of IL-6 and trigger the phosphorylation of Jak2 and Stat3, while pectolinarigenin remarkably reduced their corresponding levels. Notably, CLP-induced kidney injury of mice significantly reduced the expression of PGC-1α, OPA1 and increased the expression of Drp1, Cyt-C, where pectolinarigenin pretreatment significantly restored their corresponding expression in mice. In summary, pectolinarigenin improved septic AKI via inhibiting JAK2/STAT3 signaling and mitochondria dysfunction. [Display omitted] • Pectolinarigenin (PEC) is a natural flavonoid with anti-inflammatory properties. • PEC alleviated kidney injury against LPS/CLP-induced septic AKI mice. • PEC improved inflammation and apoptosis in kidneys of septic mice. • PEC inhibited JAK2/STAT3 and mitochondria dysfunction in kidneys of septic mice. [ABSTRACT FROM AUTHOR]

Danhong Huayu Koufuye (DHK), a traditional Chinese prescription, is used to treat central retinal vein occlusion clinically. We previously reported that DHK prevented diabetic retinopathy (DR) in rats. Moreover, we found that it protected endothelial cells from hyperglycemia-induced apoptosis through antioxidation and anti-inflammation. Here, we investigated whether antioxidative and anti-inflammatory activities of DHK contributed to its therapeutic effect on DR in streptozotocin- (STZ-) induced diabetic rats. DHK significantly blocked the breakdown of the blood-retinal barrier (BRB) and increased the thickness of the inner nuclear layer (INL), as well as suppressed the swelling of the ganglion cell layer (GCL) in diabetic retinas. DHK remarkably increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in plasma, and decreased serum level of nitric oxide (NO). Moreover, DHK markedly reduced the serum levels of vascular endothelial growth factor (VEGF) and intercellular adhesion molecule-1 (ICAM-1). Furthermore, DHK significantly downregulated protein expressions of VEGF and inducible NO synthase (iNOS) and mRNA expression of ICAM-1 in retinas. These results suggest that the antioxidative and anti-inflammatory activities of DHK may be important mechanisms involved in the protective effect of DHK on DR in STZ-induced diabetic rats. [ABSTRACT FROM AUTHOR]

Tellurite based glasses have been prepared with various glass compositions such as yBi 2 O 3 -xZnO-(100 − x − y)TeO 2 glass system (y = 0.2, 1.0, 2.0, 3.0, 4.0, 5.0, and 8.0 mol% ratio and x = 14, 19, 19.8, and 20 mol%). The purpose of the work is to investigate the effect of glass compositions on the structure and hardness under the indentation loading test. Up till now, the experiences of the preparation of tellurite based glasses showed that it has high fragility structure at room temperature compared to boroxide, and chalcogenide-based glass materials. In this study, the thermal, mechanical and structural properties of Bi - based tellurite optical glass materials were investigated at room temperature. Results indicated that increased refractive index ratio of Bi has pronounce effect upon the transition temperature while the hardness value of the lassy material showed a reduction in response to this increased refractive index value of Bi. The obtained results further could be correlated with compositions that effects on the structural changes [for TeO 4 (tbp) to TeO 3 (tb)] having non-binding oxygen (NBO) due to the elastic deformation of Te O bonding and expansion of interatomic distances when considered the data of the Vickers' hardness, FT-IR, and Raman spectra. Here, it can also be emphasized that obtained the thermal stability, (T = T x − T g ), of the glass material, decreases from 80 to 37 °C as the melting temperature increases from 800 to 1025 °C, possibly leading to a decrease in microhardness and deformation in the glass materials. [ABSTRACT FROM AUTHOR]

One-dimensional ternary nanostructures, AgCO nanorod cores coated with an intermediate layer of Ag nanoparticles (NPs) and a sheath of conducting polymer polyaniline (PANI), AgCO/Ag/PANI composite nanorods (CNRs), were successfully prepared via a facile two-step method. Ag NPs were first uniformly anchored onto the AgCO nanorods to form binary AgCO/Ag CNRs with an in situ visible-light-induced reduction strategy, and then the AgCO/Ag CNRs were coated with PANI of different contents through a simple chemisorption approach. The as-obtained hybrids exhibit significantly enhanced photoelectrochemical current response and photoactivity in degrading methyl orange under visible-light illumination ( λ > 420 nm). The improved photoactivity was found to be related to the intermediate Ag between AgCO and PANI which facilitates the separation efficiency of photogenerated carriers, and an optimal weight percent of 2.0% PANI was observed. The origin of enhanced photoactivity was further investigated by a radical-trapping test, and a Z-scheme mechanism was proposed to explain the charge separation behaviors. [ABSTRACT FROM AUTHOR]

Recent advances in gene delivery into cells allow improved therapeutic effects in gene therapy trials. To increase the bioavailability of applied cells, it is of great interest that transfected cells remain at the application site and systemic spread is minimized. In this study, we tested clinically used biodegradable poly(lactic acid-co-glycolic acid) (PLGA) scaffolds (Vicryl & Ethisorb) as transient carriers for genetically modified cells. To this aim, we used human fibroblasts and examined attachment and proliferation of untransfected cells on the scaffolds in vitro, as well as the mechanical properties of the scaffolds at four time points (1, 3, 6 and 9 days) of cultivation. Furthermore, the adherence of cells transfected with green fluorescent protein (GFP) and vascular endothelial growth factor (VEGF165) and also VEGF165 protein secretion were investigated. Our results show that human fibroblasts adhere on both types of PLGA scaffolds. However, proliferation and transgene expression capacity were higher on Ethisorb scaffolds most probably due to a different architecture of the scaffold. Additionally, cultivation of the cells on the scaffolds did not alter their biomechanical properties. The results of this investigation could be potentially exploited in therapeutic regiments with areal delivery of transiently transfected cells and may open the way for a variety of applications of cell-based gene therapy, tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

Reversible logic, as an interesting and important issue, has been widely used in designing combinational and sequential circuits for low-power and high-speed computation. Though a significant number of works have been done on reversible combinational logic, the realization of reversible sequential circuit is still at premature stage. Reversible counter is not only an important part of the sequential circuit but also an essential part of the quantum circuit system. In this paper, we designed two kinds of novel reversible counters. In order to construct counter, the innovative reversible T Flip-flop Gate (TFG), T Flip-flop block (T_FF) and JK flip-flop block (JK_FF) are proposed. Based on the above blocks and some existing reversible gates, the 4-bit binary-coded decimal (BCD) counter and controlled Up/Down synchronous counter are designed. With the help of Verilog hardware description language (Verilog HDL), these counters above have been modeled and confirmed. According to the simulation results, our circuits' logic structures are validated. Compared to the existing ones in terms of quantum cost (QC), delay (DL) and garbage outputs (GBO), it can be concluded that our designs perform better than the others. There is no doubt that they can be used as a kind of important storage components to be applied in future low-power computing systems. [ABSTRACT FROM AUTHOR]

To identify the distribution of heavy metals in sewer sediments and assess their potential harmfulness to the environment and human health, the occurrence of Pb, Zn, Cu, and Cd in the sewer sediment of six functional areas and two streets in an inner-city suburb of Beijing, China, was investigated by using a sequential extraction procedure. Results show that the concentrations of Cu, Zn, Cd, and Pb vary between 50 and 175, between 80 and 180, between 0.75 and 2.5, and between 20 and 110 mg/kg, respectively, and Fe-Mn oxide fraction is significant for all metals in sampling areas. Pollution assessment shows that 1–2% of Cu at Chegongzhuang Street and 1–3% of Zn at Fuwai Street in the exchangeable fractions are of low risk. 10–25% of Cd at six functional areas indicates medium risk. 40–60% of Pb at Fuwai Street existing in the exchangeable fractions is of high to very high risk. The sum of these metals associated with exchangeable, carbonate bound, and Fe-Mn oxide fractions is quite high; however, these three fractions represent the proportion of heavy metals that can be remobilized by changes in environmental conditions. [ABSTRACT FROM AUTHOR]

Cerebrospinal fluid (CSF) contains a tightly regulated immune system. However, knowledge is lacking about how CSF immunity is altered with aging or neurodegenerative disease. Here, we performed single-cell RNA sequencing on CSF from 45 cognitively normal subjects ranging from 54 to 82 years old. We uncovered an upregulation of lipid transport genes in monocytes with age. We then compared this cohort with 14 cognitively impaired subjects. In cognitively impaired subjects, downregulation of lipid transport genes in monocytes occurred concomitantly with altered cytokine signaling to CD8 T cells. Clonal CD8 T effector memory cells upregulated C-X-C motif chemokine receptor 6 (CXCR6) in cognitively impaired subjects. The CXCR6 ligand, C-X-C motif chemokine ligand 16 (CXCL16), was elevated in the CSF of cognitively impaired subjects, suggesting CXCL16-CXCR6 signaling as a mechanism for antigen-specific T cell entry into the brain. Cumulatively, these results reveal cerebrospinal fluid immune dysregulation during healthy brain aging and cognitive impairment. [Display omitted] • Monocytes upregulate lipid processing genes with age in cognitively normal CSF • Monocyte lipid processing genes are dysregulated in cognitively impaired CSF • Monocytes signal to clonal CD8+ T cells via CXCL16-CXCR6 in cognitively impaired CSF • CXCL16 is increased in cognitively impaired CSF and relates to neurodegeneration A single-cell transcriptomic resource exploring the cerebrospinal fluid immune system in healthy brain aging and cognitive impairment uncovers the CXCL16-CXCR6 pathway as a mediator of CD8+ T cell trafficking to the CSF. [ABSTRACT FROM AUTHOR]

As the value of TiO 2 in environmental protection continues to be explored, it has broad potential for stone building protection. However, the hydrophilicity of TiO 2 makes it challenging to keep stable on the exterior of buildings and hydroxyl radicals generated under UV irradiation may be harmful to substrates. Herein, TiO 2 was wrapped with the SiO 2 shell by a modified Stöber method and superhydrophobic TiO 2 was obtained by grafting methyl groups on the SiO 2 shell. The TiO 2 @Si–Me core-shell system were dispersed in Paraloid B72 and applied on marble surfaces to investigate the self-cleaning effect of TiO 2 on the substrate. The results showed that the superhydrophobic TiO 2 nanoparticles significantly enhanced the surface roughness, which was beneficial to transform the acrylic resin coating from hydrophilic to hydrophobic and retain the original vapor permeability. The adsorption rate and degradation efficiency of methylene blue of TiO 2 @Si–Me core-shell system were 2.19 and 1.45 times higher than that of pure TiO 2. Furthermore, the superhydrophobic TiO 2 did not change the color of the stone after UV aging, which contributed to maintaining the appearance of buildings. These findings will help to understand the role of photocatalytic nanomaterials in developing protective layers for stone construction and expand the application in the self-cleaning of the architectural environment. Graphical abstract illustrates the preparation process and superhydrophobic mechanism of TiO 2 @Si and TiO 2 @Si–Me. [Display omitted] • Superhydrophobic TiO 2 @Si–Me were prepared and applied to the Paraloid B72 coating. • The composite coating exhibits more efficient adsorption and photocatalytic activity. • TiO 2 @Si–Me increases the contact angle on marble from 69.87° to 147.61°. • The methyl provides an efficient pathway for the transfer of photogenerated electrons. • The color of the coating on stone was not changed after UV aging. [ABSTRACT FROM AUTHOR]

• A waveguide chip that disperses light and focuses it directly onto a camera without any free-space elements. • Fine spectral resolution (0.42nm) and a large focal depth (>4mm) for precise spectral analysis with relaxed system alignment. • No need for customized detectors and electronic circuits. • The chip can be easily mounted to any commercial camera for fiber spectrum analysis. We propose and experimentally demonstrate a fiber spectrum analyzer based on a planar waveguide chip butt-coupled with an input fiber and aligned to a standard camera without any free-space optical elements. The chip consists of a single-mode waveguide to connect with the fiber, a beam broadening area, and a waveguide array in which the lengths of the waveguides are designed for both wavelength separation and beam focusing. The facet of the chip is diced open so that the outputs of the array form a near-field emitter. The far field are calculated by the Rayleigh-Sommerfeld diffraction integral. We show that the chip can provide a focal depth on the millimeter scale, allowing relaxed alignment to the camera without any fine-positioning stage. Two devices with 120 and 220 waveguides are fabricated on the polymer waveguide platform. The measured spectral width are 0.63 nm and 0.42 nm, respectively. This simple and practical approach may lead to the development of a spectrum analyzer for fiber that is easily mountable to any commercial camera, thereby avoiding the complication for customized detectors as well as electronic circuits afterwards. [ABSTRACT FROM AUTHOR]

Since its inception as the cornerstone of the ultrafast pulse laser, semiconductor saturable absorber mirrors (SESAMs) have attracted considerable interest. Meanwhile, low-dimensional (LD) materials based saturable absorbers (SAs) are gaining popularity in pulsed laser applications due to their high nonlinearity, strong light-matter interaction, and low cost. Here, high-quality LD-SAs have been created by transferring 2 H-TaS 2 onto gold mirrors and covered with plasma-enhanced chemical vapor deposition (PECVD) SiO 2 layers. The non-linear transmission of SiO 2 passivated TaS 2 -SAM was measured using a balanced dual-detector technology. The modulation depth and saturated intensity were ~8.4% and 0.86 MW·cm−2. Based on the SiO 2 passivated TaS 2 -SAM, Q-switched and mode-locked Erbium-doped (Er3+-doped) fiber pulse lasers have been successfully achieved. Stable soliton pulses are obtained in erbium-doped fiber lasers (EDFLs) with pulse width of 1.8 ps, repetition rate of 3.4 MHz and a center wavelength of 1560.6 nm. Moreover, the mode-locking laser exhibited long-term stability with high signal-to-noise ratio of 63 dB. This study serves as a standard for low-dimensional materials research in photonics applications, and the results reveal that TaS 2 -SAM has a wide range of applications in multifunctional all-fiber lasers. [ABSTRACT FROM AUTHOR]

• A multi-parameter high-order extended state observer is designed to estimate lumped uncertainties. • A fixed-time fault-tolerant adaptive trajectory tracking controller is presented. • The desired trajectory is constructed by interpolating the path. • The simulation topography is built according to the TAG active mound. This paper investigates the fixed-time trajectory tracking problem of small autonomous underwater vehicles (S-AUVs) in the Trans-Atlantic Geotraverse (TAG) active mound with ocean current, unknown disturbances, model uncertainties, actuator faults, and input saturations. First, the effect of the near-bottom environment of the mound on S-AUVs is analyzed in detail from three issues. Without the upper bound and gradient of lumped uncertainties, a high-order adaptive extended state observer (ESO) is designed. Then, a continuous fixed-time sliding mode manifold is applied to obtain fast convergence performance. In order to realize the fixed-time convergence of tracking errors, an adaptive fault-tolerant trajectory tracking control law with an auxiliary dynamic system (ADS) is proposed. In addition, the simulated topography of the TAG mound is constructed and the trajectory based on path points is modeled by cubic spline interpolation. The effectiveness and superiority of the proposed algorithm are validated by comprehensive simulations. [ABSTRACT FROM AUTHOR]

Poly (L -lactic acid) microparticles (PLLAms) loaded with growth factors were prepared through the modified (ethanol as the modifier) solution enhanced dispersion by supercritical CO 2 (SEDS) for controlling release rate while maintaining bioactivity. Trypsin was used to explore operational parameters and their influence on release. Results showed that the optimized flow rate of polymer solution was 1.0 mL/min. Release rate of trypsin-PLLAms was regulated by molecular weight of PLLA and Polyethylene glycol (PEG) ratio. Bone morphogenetic protein (BMP-2), fibroblast growth factor-2 (FGF-2), and vascular endothelial growth factor (VEGF) was loaded into PLLAms. Encapsulation efficiency was 65.9%, 63.9%, and 64.3%, cumulative release rate was 63.2%, 74.8% and 84.1% for 7 days, respectively. BMP-2, VEGF and FGF-2 released from PLLAms significantly promoted cell proliferation and differentiation. Therefore, the modified SEDS effectively maintained drug bioactivity, which could be used to fabricate carriers for controlled bioactive drugs release. [Display omitted] • Solution enhanced dispersion by supercritical CO 2 (SEDS) was modified. • Polymeric microparticles loaded bioactive drugs were prepared by modified SEDS. • Bioactive drugs release was controlled by molecular weight and ratio of polymers. • Modified SEDS effectively maintained bioactivity of growth factors. [ABSTRACT FROM AUTHOR]

The G protein-coupled receptor cascade leading to production of the second messenger cAMP is replete with pharmacologically targetable proteins, with the exception of the Gα subunit, Gαs. GTPases remain largely undruggable given the difficulty of displacing high-affinity guanine nucleotides and the lack of other drug binding sites. We explored a chemical library of 1012 cyclic peptides to expand the chemical search for inhibitors of this enzyme class. We identified two macrocyclic peptides, GN13 and GD20, that antagonize the active and inactive states of Gαs, respectively. Both macrocyclic peptides fine-tune Gαs activity with high nucleotide-binding-state selectivity and G protein class-specificity. Co-crystal structures reveal that GN13 and GD20 distinguish the conformational differences within the switch II/α3 pocket. Cell-permeable analogs of GN13 and GD20 modulate Gαs/Gβγ signaling in cells through binding to crystallographically defined pockets. The discovery of cyclic peptide inhibitors targeting Gαs provides a path for further development of state-dependent GTPase inhibitors. [Display omitted] • Discovery of nucleotide-state-selective cyclic peptide binders for Gαs • Co-crystal structures reveal G protein class specificity of the cyclic peptides • Inhibition of the Gαs ON-state reduces isoproterenol-stimulated cAMP production • Sequestering the Gαs OFF-state prolongs Gβγ activation upon receptor activation Cell-permeable Gαs inhibitors regulate G protein signal transduction with high nucleotide-binding-state selectivity and class specificity. [ABSTRACT FROM AUTHOR]

Targeted design of metal defects in photocatalysts helps to realize stable and efficient wastewater treatment. Herein, a novel spinel Cu 1-x Co 2-y O 4-z with bimetal defects is precisely designed by a simple temperature programmed reduction method in hydrogen atmosphere. The co-existence of metallic defects leads to defects distortion forming polarization effect, which can significantly accelerate the separation of photogenerated carriers. By optimizing the band structure, Cu 1-x Co 2-y O 4-z induced in-situ H 2 O 2 production (190 μmol L−1·h−1 with sacrificial agent and 78 μmol L−1·h−1 without sacrificial agent) to boost the generation of hydroxyl radical, and the photodegradation activity was 7.8 and 8.4 times for MB and Cr(VI) as that of CuCo 2 O 4 , respectively. Bimetal defects achieve high performance through in-situ production of H 2 O 2 and purification of contaminants, providing novel strategies for the applications of spinel photocatalysts in environmental purification. Graphical abstract illustrates the photocatalytic mechanism on contaminants of Cu 1-x Co 2-y O 4-z. [Display omitted] • Bimetal defects initiate the in-situ effect of H 2 O 2 production to boost.•OH. • Bimetal defects induce a polarization effect to boost the separation of e−-h+. • Electric field derived from bimetal defects assists efficient photodegradation. • Cu 1-x Co 2-y O 4-z can activate. • O 2 − to attain prominent photocatalytic activity for Cr (Ⅵ). [ABSTRACT FROM AUTHOR]

The rapid development of electric vehicles significantly aggravates the demand for ternary cathode materials. However, spent lithium-ion batteries (LIBs) from portable applications, generally composed of LiCoO 2 , dominate the volume for recycling. Besides, slow leaching kinetics and low leaching capacities are crucial factors that hinder the commercialization of hydrometallurgical recycling. Here, an economically feasible process for the regeneration of LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) from spent portable electronics batteries is proposed. By introducing oxygen nano-bubbles (O 2 NBs) into the leaching solution, faster leaching kinetics and 2.5 times higher leaching capacities are obtained compared with those without O 2 NBs. The regenerated NCM622 cathode material demonstrates a well-ordered layered hexagonal structure with a low degree of Li+/Ni2+ mixing ratio, which facilitates the reliable reversible capacity, low polarization, high rate capabilities, and capacity retention ratio. By adopting thermodynamic and the first-principles calculations, the mechanism for the regeneration process is revealed. [Display omitted] • Oxygen nano-bubbles are first introduced into the leaching system. • 2.5 times leaching capacities are obtained compared with the previous report. • Thermodynamic and DFT calculations are used to interpret the regeneration mechanism. • Regenerated LiNi 0.6 Co 0.2 Mn 0.2 O 2 demonstrates excellent electrochemical properties. [ABSTRACT FROM AUTHOR]

Reciprocal Recommender Systems (RRSs) are recommender systems specifically designed for people-to-people recommendation tasks, e.g., online gaming, dating, and recruitment services. They are fundamentally different from the conventional user–item recommendations. In RRSs, user interactions are usually directional, i.e., they are initiated by one side and not necessarily reciprocated by the other side. In the meanwhile, abundant multiplex user interactions, e.g., Friend Request and Send Message , are collated by the online services and can be represented into a large-scale multiplex user interaction graph. Despite the substantial progress of Graph Neural Networks (GNNs) on capturing users' multiplex interactions, naive GNNs are insufficient to capture the additional information implied from the directions of interactions, as they are usually not designed to preserve the asymmetric proximities between users. In the paper, we present a novel Graph neural network for Reciprocal Recommendation (GraphRR) to utilize the multiplex user interactions. Specifically, three ego graphs are augmented based on the directions of interactions for each user to capture his preference, attraction and similarity in a finer granularity. Then the multiplexity-aware GNN modules are further applied to measure the contributions of different interaction types. Extensive experiments are conducted in the datasets of the real-world large-scale online games from NetEase Games , a leading game provider for worldwide users. The experimental results demonstrate the superiority of GraphRR over baseline methods and provide empirical evidence for the benefits of the proposed ego graph augmentation. The source code is also available online for reproductivity 1 1 https://github.com/changym3/GraphRR.. [ABSTRACT FROM AUTHOR]

Currently, inner-generate hydrogen peroxide to enhance the degradation of pollutants is an outstanding way. However, few studies have been done on MoS 2 photocatalysts with sulfur vacancies at the phase-junction to produce innergenerate-H 2 O 2 to promote contaminants degradation. Herein, we prepared Mo 1−x S 2−y photocatalysts with sulfur vacancies at the phase-junction by a simple method (temperature-programmed reduction in hydrogen atmosphere) to achieve high innergenerate-H 2 O 2 and high degradation efficiency. Specifically, Mo 1−x S 2−y exhibited a high yield of innergenerate-H 2 O 2 (35 μmol L−1 h−1, 1.5 times as high as bulk MoS 2) under simulated solar irradiation, because the promoted electron transfer can increase superoxide radical to generate innergenerate-H 2 O 2. Hydroxyl radicals generated by decomposition of innergenerate-H 2 O 2 through the transformation of variable metal molybdenum atom (Mo(Ⅳ)/Mo(Ⅵ)) can effectively improve the degradation efficiency of tetracycline and diclofenac sodium (twice as high as bulk MoS 2). The novel and concise way was paved to synthesize photocatalysts for high-efficiency photocatalytic degradation by innergenerate-H 2 O 2. Illustrates the mechanism of innergenerated-H 2 O 2 to improve photodegradation of PPCPs. [Display omitted] • Mo 1−x S 2−y with S vacancy in 1T phase at phase-junction was synthesized. • S vacancy results in lamellar curly, increasing reaction active sites and oxygen adsorption sites. • Photoexcited carriers and •O 2 - generated by adsorbed O 2 can promote the formation of H 2 O 2. • Mo 1−x S 2−y achieves high photodegradation properties through •OH decomposed by innergenerated-H 2 O 2. [ABSTRACT FROM AUTHOR]

• The interaction between the interface and crack in the double-layer composite rock-like specimens was considered. • The crack evolution of specimens was investigated by combining AE technology and DIC method. • Five typical failure modes were summarized: Single-layer X-conjugate failure, interface friction failure, tensile failure of the airfoil at interface, overall slip shear failure along the interface and local interface splitting tensile failure. Composite rock with interfaces is widely distributed in nature. Its mechanical properties are significantly different from those of a single layer rock, which has become one of the highlighted issues in engineering design and operation. In this study, uniaxial compression tests are performed on rock-like specimens with two dissimilar layers. The evolution process of the apparent strain field of the specimen is analysed by digital image correlation (DIC). Acoustic emission (AE) technology is used to analyse the damage evolution process of specimens based on energy dissipation theory and the damage evolution model. The research results show that with the increase in the interface angle, the peak compressive strength of the specimen decreases slowly first and then decreases rapidly, increasing when reduced to the minimum. When the inclination angle of the specimen interface is 60°, its strength is the lowest. The higher the overall strength of the specimen is, the more obvious the above phenomenon. DIC technology captures the apparent strain field characteristics of each stage of specimen failure, which provides a basis for the analysis of the specimen failure mode. The failure modes of the specimens can be divided into five categories. When the inclination angles of the interface are 0°, 60°, 75° and 90°, the failure modes of the specimens are mainly affected by the inclination angle. When the inclination angles are 15°, 30° and 45°, the failure modes are affected by the inclination angle and the rock matrix strength. The damage evolution process of most specimens is divided into four stages. Some specimens only show three stages, such as those specimens with an interface inclination angle of 60°. [ABSTRACT FROM AUTHOR]

Development of rapid molecular detection technologies is critical for the safer and smarter urban agriculture, medicine, and pro-environment. The emergent terahertz (THz) spectroscopy has its distinct advantages of being non-destructive, label-free and able to trace intermolecular and intramolecular vibrations, yet it suffers from the low performance of sensing materials available and their high fabrication cost. Here, we introduce a reticular material -- two dimensional (2D) covalent organic frameworks (COFs) and prepare their nanofilms as the lossy layer for THz absorbers. The COF film can be directly deposited on the dielectric layer of THz absorbers via an in-situ wet-chemistry growth. It possesses designable hierarchical structures, high specific areas of 736–971 m2/g, and precise nanopores of 1.6–2.1 nm, depending on its 2D COF constituents. The resulting THz absorber has been tested for pesticide detection. It presents a limit of detection at 2.2 ng and a selective response of 2.7–7.8 times that of interferents such as saccharides, antibiotics, and dyes, satisfying the need for practical application. Such flexible filmy sensor can measure the pesticide residue on the surface of apple for practical application. The THz sensor also demonstrates high stability over 1000 cycles of bending. Use of reticular nanofilm as the responsive layer may permit the future development of high-performance THz absorbers and other sensors for rapid molecular recognition. [ABSTRACT FROM AUTHOR]

In this study, coal gangue (CG) was applied as media in bioretention system to remove runoff pollutant. CG modified bioretention systems show good removal efficiency towards runoff pollutant due to the high adsorption capacity of CG. The removal of total phosphorus (TP), total nitrogen (TN), ammonia (NH 4 +-N) and chemical oxygen demand (COD) by CG modified bioretention systems was influenced by diverse rainfall conditions including rainfall concentration, recurrence period and drying period, and their removal rate ranged 94–99%, 30–70%, 83–97% and 33–86%, respectively. The effluent concentration of Zn, Pb and Cu was as low as 3.14–10.99 μg/L, 0.66–2.56 μg/L and 0.60–3.15 μg/L, respectively. In addition, CG could promote the plant heavy metal uptake and thus decrease their accumulation in soil to a certain extent. Meanwhile, Malondialdehyde (MDA) content and peroxidases (POD) activities of plants in CG modified bioretention were lower than that in tradition bioretention, indicating that CG could help plants recovery and lessened the oxidative stress for the negative impact of high heavy metals accumulation. CG-based media alleviated the inhibitory effect of rainwater runoff pollutant accumulation (especially heavy metals) on microbial diversity and the enhancement of the dominant bacteria (such as Proteobacteria and Bacteroidota) could conduce the nutrients removal in the bioretention systems. In overall, this study demonstrated that the CG modified bioretention systems show an excellent removal performance combine with biological effects. [Display omitted] • The CG modified bioretention improves the removal of nutrients and heavy metals. • Rainfall recurrence and drying periods could influence the removal of pollutants. • Bioretention with CG-based media and CG filter show best removal efficiency. • CG improves heavy metal uptake in plants and relieve the stress of heavy metals. • CG promotes microbial diversity and enhances the dominant bacteria in bioretention. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-Co 2 C active sites can be adjusted by changing the ratio of Co/Ti. • Oxygen vacancy could eliminate carbon deposition and promote higher alcohols synthesis. • Co0, Co 2 C and oxygen vacancies synergistically boost the formation of higher alcohols. • The complete perovskite structure is beneficial to the excellent stability of catalyst. Catalytic conversion of syngas (CO + H 2) to higher alcohols is desirable, but a high C 2+ OH selectivity is challenging to achieve due to the difficult equilibrium between dissociatively adsorbed CO and non-dissociatively adsorbed CO. In this work, Ca 1-x La x Ti 1-x Co x O 3 catalysts are facilely prepared by using citrate complexing method, and a part of metal Co is transformed to Co 2 C during reaction. In the process of reaction, the synergistic effects among metal Co, Co 2 C and oxygen vacancies boost the conversion of syngas to higher alcohols. Metal Co nanoparticles are used to promote the dissociative adsorption CO and C–C coupling, subsequently combine with *CO adsorbed on Co 2 C to produce alcohols. Besides, oxygen vacancy can be used to activate oxygen-containing compounds and enhance higher alcohols synthesis. The surface Co 2 C/Co ratio has significant influences on catalytic activity and stability of catalysts, which can be adjusted by the Co/Ti ratio. The C 0.7 L 0.3 T 0.7 C 0.3 O 3 catalyst exhibits the highest selectivity of higher alcohols due to the moderate surface Co 2 C/Co ratio, which has an appropriate balance between *C, *CO and C–C coupling. [ABSTRACT FROM AUTHOR]