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To safeguard water quality and sustainable phosphorus cycling, it is imperative to recover phosphorus from high-content wastewater, particularly livestock wastewater, considering the low tolerance threshold for phosphate in surface water (below 0.5 mg/L). Calcium carbonate and magnesium carbonate possess considerable potential for phosphate adsorption; however, their crystalline nature diminishes the reactivity of calcium and magnesium, resulting in the limited phosphate adsorption capacity. In this study, a novel phosphate adsorbent (PCCM@K) was synthesized through co-precipitation involving Ca, Mg, and pectin, followed by direct coating with konjac glucomannan, which eliminated the need for separation and cleaning steps. Pectin macromolecules interact with Ca and Mg to yield amorphous minerals, thereby enhancing the pore structure. The assessment of the phosphate adsorption performance of PCCM@K reveals robust alkali release, stable adsorption across a broad pH range (3−12), high adsorption capacity (61.9 mg-P/g), minimal interference from coexisting ions, and effective phosphate recovery in the actual biogas slurry. The primary mechanism underlying phosphate adsorption is chemisorption. During the adsorption process, ligand exchange takes place between carbonate and phosphate, leading to an increase in solution pH and the immobilization of phosphate via inner-sphere complexation with Ca and Mg. Overall, PCCM@K exhibits considerable potential for phosphorus recovery from wastewater, highlighting its significance in promoting environmentally sustainable practices. [Display omitted] • Amorphous carbonate minerals were obtained by co-precipitation of pectin, Ca, and Mg. • The formation of amorphous calcium magnesium carbonate enhanced the phosphate adsorption capacity. • KPCCM has a strong alkali release, stabilizing its adsorption capacity in a wide pH range (3−12). [ABSTRACT FROM AUTHOR]

Estimated Time of Arrival (ETA) for packages plays an essential role in intelligent logistics. As a classic ETA method, Origin–Destination-based (OD-based) ETA predicts the delivery time only based on the attributes (i.e. , sender address, receiver address, seller, and payment time) of packages under the condition that the delivery route is unavailable. However, existing OD-based methods only exploit attributes associated with an individual order, which fails to model the higher-order interactions within orders and attributes, and fail to sufficiently exploit the graph-structure knowledge (i.e. , relation of orders and attributes) and feature-based knowledge (i.e. , statistical properties) of orders simultaneously, resulting in inaccurate predictions. In this paper, we propose a novel Heterogeneous HyperGraph Neural Network (H 2 GNN) for estimating package arrival time. Specifically, to better capture the high-order interactions within orders and attributes, we construct an order heterogeneous hypergraph that utilizes hyperedges to represent orders and nodes to represent order attributes. Besides, we extend the hypergraph learning for large-scale e-commerce data by Hyper-GraphSAGE. Overall, H 2 GNN can provide informatively representations of packages while preserving both structure-based knowledge learned by hypergraph and feature-based knowledge captured by Transformer. Experimental results on large-scale Alibaba logistics data demonstrate the superior performance of H 2 GNN compared to the baselines. [ABSTRACT FROM AUTHOR]

In deep mining, surrounding rock mass are subjected to high in-situ stress and dynamic loading, which leads to the difficulties in maintaining the roadway stability. Therefore, it is important to investigate the mechanical characteristics of rock bolts and their ability to enhance stability when exposed to static and dynamic coupled loading (SDCL). 3D printing technology can effectively address the challenges of preparing weak rock specimens and overcoming high variability. Consequently, the Split Hopkinson pressure bar (SHPB) is used to conduct SDCL testing on 3D printing specimens with varying bolted lengths. The similarity in mechanical performance between sand-powder 3D printed specimens and natural coal specimens has been validated. The rock dynamic characteristics with different bolted lengths under SDCL of specimens were explored. The macroscopic fragmentation and microscopic electron microscope scanning were used to reveal the dynamic failure characteristics of specimens. The study shows that static, dynamic and combined strength are positively correlated with bolted length. The dynamic strength is negatively correlated with the axial stress, and the combined strength initially increases and then subsequently decreases as the axial stress increases. The dynamic strength and the combined strength are positively correlated with the impact pressure. Efficient prevention of specimen fracture was achieved by increasing the length of the bolted connection. It can be found that at the meso-scale, when the specimen is only under the static loads, the cross-section particles are fractured along particle bonding, and under the SDCL, there are fractured along particle bonding and fractured through particle. The conclusions obtained can offer a foundation for conducting dynamic rock mechanics experiments using sand-powder 3D printed specimens and for controlling the surrounding rock in dynamic pressure roadways. • The dynamic behaviors of sand power 3D printing specimens are revealed. • The mechanical similarity between the 3D printing specimens and coal are confirmed. • The macro-mesoscopic failure modes under different dynamic loadings are clarified. • The bolted strengthening effect under static and dynamic loads is obtained. [ABSTRACT FROM AUTHOR]

In this study, novel kinds of MMMs were fabricated by incorporating ZIF-67 nanoparticles into polymers of intrinsic microporosity (PIM-1). ZIF-67 (Co substituted ZIF-8) displays stiffer Co-N bond as compared with the Zn-N bond in ZIF-8, which might led to the slightly smaller effective pore aperture of ZIF-67. Good compatibility between ZIF-67 nanoparticles and PIM-1 matrix rendered ideal interfacial morphology. The intrinsic separation performance of ZIF-67 was estimated from our experimental separation results based on the Maxwell model. The calculation demonstrated its superior CO 2 /CH 4 selectivity of 45, which is twice compared with that of ZIF-8, supporting the high molecular sieving efficiency of PIM-1/ZIF-67 MMMs. Particularly, the CO 2 and H 2 permeability increased by 15.1% and 59.6% for PIM-1 membrane with 20 wt% ZIF-67 loading, meanwhile CO 2 /CH 4 and H 2 /CH 4 selectivity increased by 34.4% and 86.96%, respectively. The strategy of incorporating highly selective ZIFs into polymers of intrinsic microporosity may have promising potential in fabricating high performance membranes for efficient gas separation. [ABSTRACT FROM AUTHOR]

• Considering different sensor characteristics of the indoor mobile robot, sensor measurement models of IMU, Odometer and LiDAR are constructed. • The factor graph positioning model fuses asynchronous nonlinear sensor information and optimizes incremental robot state estimation using an iterative approach. • Dynamic adaptation function detects sensor anomaly information in real time to improve the robustness of multi-sensor fusion positioning system. • The proposed algorithm reduces mean location errors by about 40% compared to conventional positioning methods under normal and abnormal sensor conditions. Navigation and positioning based on sensor fusion has received great attention in low computational complexity, high positioning accuracy and good robustness for indoor mobile robots. This paper presents a multi-sensor fusion factor graph (MSF-FG) positioning method applying IMU, Odometer and LiDAR sensors. By taking advantage of the sensor characteristics and using factor graph theory, a MSF-FG positioning model is constructed to improve positioning accuracy and reduce computational complexity. In addition, an adaptive function is designed to improve the robustness of the system by dynamically adjusting the weight of each factor. Meanwhile, the proposed algorithm is derived by Gauss-Newton and Levenberg-Marquardt methods. Simulation and experimental results show that compared with the conventional inertial navigation system (INS) and extended Kalman filter (EKF) algorithms, the proposed MSF-FG positioning method not only reduces the mean location error by about 40%, but also reduces the computational complexity and enhances the stability of the system. [ABSTRACT FROM AUTHOR]

Aims Laminaria Japonica Polysaccharides (LJP) is a kind of plant polysaccharide isolated from Laminaria Japonica Aresch. LJP has a variety of biological activity, including anti-tumor, improving immune function, anti-radiation and others. This study observed the biological activity of LJP in vitro and in vivo on human nasopharyngeal carcinoma(NPC), and the possible anticancer mechanism was explored. Methods Nasopharyngeal poorly differentiated squamous cell carcinoma cell lines CNE2 and HONE1 were used for the study. MTT method was used to detect the proliferation of HONE1 and CNE2 treated with gradient concentrations of LJP. The apoptosis of HONE1 treated with LJP was detected by annexin V-FITC/PI double staining method. HONE1 was used to establish subcutaneous implanted tumor model in nude mice. The changes of transplanted tumor volume and body weight of nude mice in each group were observed and recorded. The changes of the ultrastructure of transplanted tumor were observed by transmission electron microscope (TEM). Results MTT results showed that LJP has inhibitory effect on proliferation of both HONE1 and CNE2, and the effects were dosage-dependent; results of flow cytometry (FCM) analysis showed that, LJP could efficient induce apoptosis in HONE1, and apoptosis rate increased with the increase of LJP concentration. In vivo experiments, the inhibition rate was 33.7% (P < 0.05) and 47% (P < 0.01) in middle and high dose LJP group, respectively. TEM results suggested that the cancer cells in the transplanted tumor tissue treated with middle and high dose LJP presented unique apoptosis changes. Conclusions LJP can effectively inhibit the growth of NPC cells. And it may be achieved by inducing apoptosis of NPC cells. [ABSTRACT FROM AUTHOR]

Polymers of intrinsic microporosity (PIMs) exhibit the inherent superior permeability over traditional commercial polymers, however, the relatively low selectivity restrict their broad application in gas separation. In this study, novel kinds of mixed matrix membranes (MMMs) combined covalent organic frameworks (COFs) and PIMs were prepared and utilized for improving the selectivity of carbon capture process. Covalent organic framework (SNW-1) was synthesized via Schiff base chemistry and incorporated into polymer of intrinsic microporosity (PIM-1) to prepare MMMs. Pure gas permeation tests and mixed gases separation performances of the MMMs were conducted. Owing to its proper porosity characteristics and good compatibility with PIM-1 matrix, the incorporation of SNW-1 significantly intensified the diffusion process of CO 2 within the membrane. Compared with pure PIM-1 membrane, the prepared MMMs showed an increment of 27.4% and 37.6% in selectivity of CO 2 /CH 4 and CO 2 /N 2 along with an enhancement of 116% in CO 2 permeability. The strategy of incorporating COFs into polymers of intrinsic microporosity may hold promising potential in preparing high performance MMMs for gas separation. [ABSTRACT FROM AUTHOR]

A series of Yb3+, Ho3+, Nd3+ doped Na 3 Y(VO 4) 2 phosphors are prepared by the high temperature solid reaction method. Na 3 Y(VO 4) 2 : Yb3+, Ho3+ present bright yellow emission under the excitation of 980 nm. The introduction of Nd3+ can effectively absorb 808 nm photon energy, realizing the energy transfer process of Nd3+ (sensitizer)→Yb3+ (energy transfer bridge)→Ho3+ (activator) under 808 nm excitation. Up-conversion mechanism proves that the variable luminescence color at different concentrations Nd3+ doped samples may be attributed to back energy transfer between Ho3+ and Nd3+. Moreover, the temperature sensing behaviors are investigated by the fluorescence intensity ratio technology. The maximum temperature sensing sensitivities can be maintained as a constant of 10 × 10−3 K over the whole temperature measurement range (298–618 K), which is beneficial to achieve stable optical thermometry. The phosphors can achieve color tunable luminescence within green and yellow region by adjusting the temperature. Ho3+ activated Na 3 Y(VO 4) 2 phosphors with excellent sensitivity performance have excellent prospects in the fields of optical anti-counterfeiting and temperature sensing. • The luminescent properties of Ho3+ in Yb3+ and Nd3+ sensitized systems are analyzed under 980 and 808 nm excitation. • Lifetime analysis verifies that Yb3+ is an important energy transfer bridge between Nd3+ and Ho3+ under 808 nm excitation. • Temperature sensing behaviors of Na 3 Y(VO 4) 2 : Yb3+, Ho3+, (Nd3+) are investigated by the FIR technology. • The maximum temperature sensing sensitivities can be maintained within the whole temperature measurement range (298–618 K). • Color tunable luminescence within green and red regions is realized with the increasing temperature. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis and photochemical behavior of two two-branched sulfonium-based photoacid generators (PAGs). The branched structure influences the optical properties of the PAGs by increasing absorption wavelengths and molar extinction coefficients as well as enhancing acid production under one/two-photon irradiation. The two-branched structures collectively showed twofold higher H + production abilities and improved two-photon absorption cross-sections compared with those in the corresponding mono-branched PAGs. Photochemical mechanisms were investigated through UV–Vis spectra analysis, molecular orbital calculations, and fluorescence analysis. These novel two-branched D-π-A type sulfonium-based photoinitiating systems are efficient cationic photoinitiators (epoxide conversion = 70%–85% and vinyl conversion > 75%) even under conditions with low initiator concentration (1 wt%) and curing light intensities (5 mW cm −2 ) upon exposure to visible light-emitting diodes (e.g., 405 nm). These two-photon fabricated microstructures also exhibit potential as cationic two-photon initiators. [ABSTRACT FROM AUTHOR]

Two D-π-A-type aryl dialkylsulfonium salts with substituted-fluorene as a conjugated system were developed as one-component, versatile photoinitiators under soft irradiation conditions (365–450 nm Light-emitting diodes). The mechanisms for photochemical generation of reactive species (cations and radicals) by the photoinitiators were studied by UV–Vis spectroscopy, theoretical calculations, fluorescence spectroscopy and cyclic voltammetry techniques. The high quantum yields for acid generation (Φ H + = ∼0.43 to 0.63) of the compounds enable the cationic polymerizations of epoxides and vinyl ether to proceed effectively. Meanwhile, the photocleavage products of sulfoniums (i.e., radicals) initiate the free radical polymerization of acrylate. Such versatile properties allowed them to serve as effective photoinitiators for the synthesis of interpenetrated polymer networks and thiol-ene polymerization without any co-initiators or additives. Based on their beneficial features, these photoinitiators hold great promise for use in photocuring applications. [ABSTRACT FROM AUTHOR]

Object tracking via depth image sequences can output 3D motion trajectories, and is effective in solving many traditional problems such as illumination changes and projective distortion. However, the influence of complex scene in depth-based tracking has received little attention. Depth tracker is susceptible to many kinds of disturbances, such as nearby objects, moving distracters and noise, and these properties need to be considered in the design of a robust tracking algorithm. In this paper we investigated the depth image-based object tracking problem by a typical application: hand tracking. Firstly the properties of depth image and the disturbances are discussed. Secondly two different depth trackers are proposed to handle different scenarios: one is based on depth frame differencing, and the other one is based on the mean shift algorithm which is modified to utilize depth information. Finally, a robust fused tracker is proposed based on the two different trackers. This approach was tested on two groups of depth image sequences recorded by a Kinect device, and the experimental results show that the fused tracker is competent for accurate 3D hand tracking even under very complex scene. [ABSTRACT FROM AUTHOR]

Abstract: The water-soluble phosphonate functionalized spherical platinum nanoclusters (Pt-NCs) composed of primary nanoparticles are synthesized by the thermal decomposition of platinum(IV)-complex. The size, morphology and structure of Pt-NCs are analyzed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Attachment of phosphonate groups on Pt surface is confirmed by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and zeta potential analysis. The phosphonate functionalized Pt-NCs efficiently suppress the oxygen reduction reaction (ORR) while fully preserving the Pt-like activity for the hydrogen peroxid reduction reaction. Importantly, at certain cathodic potential, only reduction reaction of hydrogen peroxide occurs at the Pt-NCs surface. Consequently, the phosphonate functionalized Pt-NCs can be used to fabricate a new kind of hydrogen peroxide electrochemical sensor with high performance in the presence of oxygen. Under optimized experimental conditions, the hydrogen peroxide electrochemical sensor shows fast response (less than 2s) and wide linear range (1.0×10−6–1.0×10−3 M) in the presence of oxygen. The results presented here indicate an important new direction in the quest to design selective catalysts for the fabrication of noble-metal based H2O2 electrochemical sensor. [Copyright &y& Elsevier]

• Nano-sized ZIF-67 was synthesized and incorporated into PIM-1 matrix. • The resultant MMMs showed significantly enhanced CO 2 /CH 4 selectivity. • The nano-sized fillers afforded an improved polymer-filler compatibility. • A modified Maxwell model was proposed to elucidate the gas transport behaviors. Membrane-based separations are of energy-efficient and environmentally benign attributes for biogas energy developments. Membranes from polymers of intrinsic microporosity (PIMs) often suffer from low selectivity. In this study, remarkable enhancements in CO 2 /CH 4 selectivity of PIM-1 membranes are achieved by incorporating nano-sized ZIF-67 (ZIF-S) filler with a larger specific surface area and a better compatibility, thereby fortifying the interactions with PIM-1 matrix and effectively alleviating nonselective interfacial voids. For the resulting PIM-1/ZIF-S membranes, a maximum CO 2 /CH 4 selectivity of 21.1 was acquired with 15 wt% loading of ZIF-S, an increase of 69.40% compared with the pristine PIM-1 membrane, along with an associated CO 2 permeability above 2800 Barrer. To elucidate gas transport behaviors within membranes, a modified Maxwell model is developed and the calculation results match well with the experimental data. The strategy of incorporating framework nanofillers into membranes may find promising applications in enhancing the selectivity of highly permeable polymer membranes. [ABSTRACT FROM AUTHOR]

Root-induced changes play a crucial role in influencing the fate and speciation of potentially toxic elements (PTEs) in contaminated soils, but their role in the phytostabilization of waste slag sites remain unclear. The aim of this study was to determine the effect of four phytostabilization plants, Broussonetia papyrifera , Arundo donax , Robinia pseudoacacia , and Cryptomeria fortunei , planted in a zinc smelting waste slag site for 5 years on PTEs speciation and the mineral and aggregation characteristics at the interface of the waste slag-plant system. The results showed that the presence of a higher content of oxalic acid in the rhizosphere slags of the four plant species than in the bare slag. Revegetation of the waste slag with the four plant species significantly changed the mineral composition and morphology of the waste slag. The mass percentage of large particles (1–5 mm) and small particles (0.5–1 mm, 0.25–0.5 mm, and <0.25 mm) in the rhizosphere slags decreased and increased, respectively. The PTEs (Cu, Pb, Zn, and Cd) in most of the rhizosphere slags were mainly distributed within the small particles, and the enrichment coefficients of PTEs in the large particles and small particles were less than and greater than 1, respectively. The bioavailability of the PTEs in the waste slag increased with decreasing particle size. Root-induced the transformation of acid-soluble PTEs into their reducible, oxidizable, and residual forms in the different waste slag particles weathered in the rhizosphere. These results suggested that there are root-induced changes in the aggregation characteristics and geochemical behaviours of PTEs in waste slag fractions during the phytoremediation of waste slag sites. Image 1 • Root-induced changes in the minerals, morphology, and aggregation of waste slag. • The distribution characteristics of PTEs differ in the different waste slag fractions. • The bioavailability of PTEs increased with decreasing waste slag fraction size. • The percentage of PTEs forms decreased with decreasing waste slag fraction size. [ABSTRACT FROM AUTHOR]

Herein, Na 3 Y(VO 4) 2 :Nd3+,Yb3+,Ho3+/Er3+/Tm3+ are synthesized through the solid-state reaction method. By utilizing Yb3+-mediated energy transfer in Nd3+-sensitized various activators (Ho3+/Er3+/Tm3+) system, 808 nm excited multi-color upconversion luminescence is realized. Yb3+ plays an important role in energy transfer bridging, and the introduction of Yb3+ in Nd3+-sensitized system can significantly improve emission of activators by nearly two orders of magnitude. The main luminescence mechanism of Nd3+→Yb3+→Activators (Ho3+/Er3+/Tm3+) is proved via measuring the emission characteristics and luminescence decay curves. With efficient upconversion luminescence, the optical thermometry behaviors for Na 3 Y(VO 4) 2 :Nd3+,Yb3+,Ho3+/Er3+/Tm3+ are investigated. The maximum relative and absolute sensitivities are 1.08 % K−1 and 7.82 × 10−3 K−1 for Na 3 Y(VO 4) 2 :Nd3+,Yb3+,Er3+; 1.01 % K−1 and 4.22 × 10−3 K−1 for Na 3 Y(VO 4) 2 :Nd3+,Yb3+,Tm3+; and 1.08 % K−1 and 22 × 10−3 K−1 for Na 3 Y(VO 4) 2 :Nd3+,Yb3+,Ho3+, respectively. Based on the multi-color upconversion luminescence and high sensitivity thermometry performance, the Na 3 Y(VO 4) 2 :Nd3+,Yb3+,Ho3+/Er3+/Tm3+ phosphors have potential applications in fields of solid-state display and safety sign of high-temperature. [ABSTRACT FROM AUTHOR]