Search

On account of the uneven level of ecological and environmental protection in the countries along the Belt and Road, infrastructure construction and investment cooperation around natural resource-intensive industries such as steel, energy, and nonferrous metals can easily induce serious ecological problems. It is necessary and practical to provide enterprises with timely and effective ecological circumstantial information of Belt and Road and pilot the establishment of the Belt and Road infrastructure construction activities with appropriate ecological risk prevention and control mechanisms. In this study, we researched the ecological risk level distribution of the countries along the Belt and Road by using ESA global land cover data and ecological risk index mode of land use. Kuwait, one of the most representative countries along the Belt and Road, was selected to analyze its spatial distribution of ecological risk by using ordinary Kriging interpolation. The results show several aspects. There existed high-ranking ecological risks in the following countries: Saudi Arabia in the Middle East, Turkmenistan in the Central Asian, Mongolia in East Asia and Pakistan in South Asia and so on; the medium ecological risks appear in the following countries: Ukraine in Eastern Europe, India, Bangladesh in South Asian, Kazakhstan and Kyrgyzstan in Central Asia the low ecological risk countries mainly include Russia, most Eastern European countries represented by Poland, and most Southeast Asian countries represented by Thailand. In the case, Kuwait's risk level is high in urban areas, medium in desert areas, and low along the Persian Gulf, showing a layered and striped distribution. Most areas in Kuwait are medium ecological risk zones with a relatively small area of high ecological risk and low ecological risk areas clustered in the eastern part of Kuwait. To effectively lower the ecological risk levels of countries along B&R, we suggest establishing B&R ecological risk prevention and control mechanisms while ecological conservation technologies are also worth noting.

Inducing ferromagnetism into graphene is vital today because it has a wide range of applications such as spintronics devices and magnetic memory devices. In this paper, we will report a new method to synthesize ferromagnetic graphene by nitrogen doping. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were utilized to testify the N-doped material and further discuss the N-doped process. The superconducting quantum interference device (SQUID) was put in and used to analyze the magnetic properties of the N-doped graphene sheets. It shows that the material exhibits ferromagnetism at both 3 K and 300 K and the ferromagnetic saturation moment is 0.412 emu/g and 0.051 emu/g respectively. The mechanism of the origin of the ferromagnetism in N-doped graphene sheets will also be discussed in this paper. It shows that, when the amount graphitic N reached the threshold, the origin of the ferromagnetism will change from defects induced by nitrogen atoms to the transition in energy band caused by graphitic N.

Using hydrazine hydrate (N2H4·H2O) as precipitant, micro-flowers NiWO4 was prepared by co-precipitation and low-temperature heat treatment, and its capacitance was studied. The different amount of N2H4·H2O resulted in two different morphologies of the samples. The electrochemical performance of the sample was tested by CV, GCD, and EIS. The results show that the specific capacitance of the nickel tungstate electrode is 170 F g−1 when the current density is 1 A g−1 in 6 M KOH solution, and the specific capacitance and rate performance of the sample are greatly improved.

Ionic liquids (ILs) can serve as effective CO2 solvents with an appropriate selection of different anions and cations. However, due to the large library of potential IL compositions, rapid screening methods are needed for characterizing and ranking the expected properties. We have recently proposed the ionic polarity index (IPI) parameter, effectively connecting volume-based approaches and electrostatic potential analyses and providing a single metric that can potentially be used to rapidly screen for desirable IL properties. In this work, the corresponding anion and cation IPIs are used to generate correlations with respect to the CO2 volumetric solubility in ILs. The relationships are generally applicable to groups of ILs within a homologous ion series, and this can be particularly valuable for prescreening different ion pairings for maximizing gas solvation performance.

A zirconium-based metal–organic framework (DUT-69) was fabricated via a hydrothermal synthesis for U(VI) removal in aqueous solutions. Experimental results showed that the maximum adsorption capacity for U(VI) was 362.32 mg·g−1 at 303 K, pH = 6 and initial U(VI) concentration of 80 mg L−1. The adsorption process fit well with the pseudo-second-order kinetic and Langmuir models. Various characterizations indicated that complexation interactions was the central adsorption mechanism and electrostatic was the secondary. The carboxyl, Zr–O, and C–S bonds in the framework participated in the adsorption process. Reusability experiments showed that 80.34% adsorption rate could be maintained after 5 cycles.

Although fullerenes were discovered nearly 35 years ago, scientists still struggle to isolate "single molecule" tubular fullerenes larger than C90. In similar fashion, there is a paucity of reports for pristine single-walled carbon nanotubes (SWNTs). In spite of Herculean efforts, the isolation and properties of pristine members of these carbonaceous classes remain largely unfulfilled. For example, the low abundance of spherical and tubular higher fullerenes in electric-arc extracts (

Molecular dynamics simulations and complementary experiments are used to understand the inter- and intramolecular structures and conformational properties of ionenes (i.e., cationic polymers formed...

Bacterial infection has become an urgent health problem in the world. Especially, the evolving resistance of bacteria to antibiotics makes the issue more challenging, and thus new treatments to fight these infections are needed. Antibacterial photodynamic therapy (aPDT) is recognized as a novel and promising method to inactivate a wide range of bacteria with few possibilities to develop drug resistance. However, the photosensitizers (PSs) are not effective against Gram-negative bacteria in many cases. Herein, we use conjugated meso-tetra(4-carboxyphenyl)porphine (TCPP) and triaminoguanidinium chloride (TG) to construct self-assembled cationic TCPP-TG nanoparticles (NPs) for efficient bacterial inactivation under visible light illumination. The TCPP-TG NPs can rapidly adhere to both Gram-negative and Gram-positive bacteria and display promoted singlet oxygen (1O2) generation compared with TCPP under light irradiation. The high local positive charge density of TCPP-TG NPs facilitates the interaction between the NPs and bacteria. Consequently, the TCPP-TG NPs produce an elevated concentration of local 1O2 under light irradiation, resulting in an extraordinarily high antibacterial efficiency (99.9999% inactivation of the representative bacteria within 4 min). Furthermore, the TCPP-TG NPs show excellent water dispersity and stability during 4 months of storage. Therefore, the rationally designed TCPP-TG NPs are a promising antibacterial agent for effective aPDT.

Clinically approved doxorubicin (Dox)-loaded liposomes (e.g., Doxil) guarantee good biosafety, but their insufficient nuclear delivery of Dox (

In plants, nitrogen remobilization from source to sink organs is an important process regulated by complex transcriptional regulatory networks. However, the relationship between nitrogen remobilization and leaf senescence and the molecular regulatory network that controls them are unknown in maize. Here, using 15N labeling and a transcriptome approach, a dynamic analysis of the nitrogen remobilization process was conducted in two elite maize inbred lines (PH4CV and PH6WC) with contrasting leaf senescence. PH4CV showed higher nitrogen remobilization efficiency (NRE) than PH6WC, mainly in the middle and lower leaves from 15 d to 35 d after silking. The co-expression network analysis revealed that ethylene and cytokinin metabolism-related genes triggered the onset of nitrogen remobilization, while abscisic acid and jasmonic acid biosynthesis-related genes controlled the progression of nitrogen remobilization. By integrating genetic analysis, functional annotation, and gene expression, two candidate genes underlying a major quantitative trait locus of NRE were identified, namely an early senescence acting gene (ZmASR6) and an ATP-dependent Clp protease gene (GRMZM2G172230). Hormone-coupled transcription factors and downstream target genes reveal a gene regulatory network for the nitrogen remobilization process after silking in maize. These results uncovered a sophisticated regulatory mechanism for nitrogen remobilization, and further provided characterization of valuable genes for genetic improvement of nitrogen use efficiency in maize.

We report the study of current-induced magnetization switching in the Ta/CoFeB heterostructures by simultaneous magneto-electrical transport and magneto-optical Kerr effect (MOKE) microscopy measurements. Although the anomalous Hall hysteresis loop summarizes the general switching behaviors, the supplementary MOKE data can provide spatial and temporal information to visualize the magnetic domain evolution as functions of the applied current and the in-plane magnetic field. More importantly, when the initial magnetic field is not sufficient enough, the interfacial Dzyaloshinskii–Moriya interaction (DMI) would modulate the spin-orbit torque (SOT) current switching dynamics and lead to the formation of the intermediate Hall resistance plateau with meta-stable tilted domain texture. Our work elucidates the importance of the applied in-plane field and unveils an effective approach to investigate the SOT/DMI-related phenomena in symmetry-breaking magnetic heterostructures.

Developing intrinsically mitochondria-targetable nanosystems for subcellular structure-oriented precise cancer therapy is highly desirable. Here, we conjugate the cluster determinant 44 (CD44)-targetable hyaluronic acid (HA) with cholesterol-poly(ethylene glycol)2k-NH2 and mitochondria-acting IR825-NH2 (a cyanine dye) to construct a self-assembled nanostructure (abbreviated as HA-IR825-Chol) for photothermal therapy. The HA-IR825-Chol exhibits improved photostability and desirable photothermal properties, and can rapidly and substantially enter CD44-overexpressed cancer cells and selectively accumulate in the mitochondria of the cells. Upon near-infrared laser irradiation, it can induce severe mitochondrial damage, which causes cytochrome c release and triggers cell apoptosis. Furthermore, we demonstrate the feasibility of loading the chemotherapeutics 10-hydroxycamptothecin (HCPT) into the hydrophobic cores of HA-IR825-Chol NPs for combined chemo-photothermal therapy. HCPT encapsulated within HA-IR825-Chol achieves significantly increased cellular uptake and simultaneous mitochondrial and nuclear localization, leading to the release of cytochrome c from mitochondria and upregulation of cleaved caspase-3, both of which contribute to the cell apoptosis/death. In vivo experiments reveal the excellent tumor-targeting ability of HA-IR825-Chol/HCPT, ensuring the efficient tumor eradication by the chemo-photothermal therapy. This work exemplifies the development of an intrinsically mitochondria-targetable nanocarrier for precise subcellular structure-localized drug delivery, and the Chol-mediated rapid and massive endocytosis of the nanoagents may represent a robust strategy for enhancing the efficacies of nanomedicines.

This study proposes a novel non-linear dynamic worm propagation model in order to describe the dynamics model of conditional triggered worm's propagation in the network, then proposes an immune dynamics model. First, the authors build impact factor according to actual condition; second, the conditions trigger type worm propagation model is established and the corresponding immune model is constructed; third, the epidemic is deduced non-toxic balance and do not sufficient conditions for the flood of worm is proved based on the theory of worm propagation model, and then the conditions of the worm will not overflow sufficient is proved through simulation experiments; finally, according to the simulation analysis and the characteristics of worm propagation, a series of control strategies are proposed, as well as the changing trend of worms in the network with immune ability. A series of simulation results show that the proposed models are reasonable and effective, it can more accurately reflect the worm propagation process in the real peer-to-peer (P2P) network, which can also accurately predict the worm propagation trend in P2P network.

In this paper, we introduced a novel method to prepare the few-layer nitrogen-doped graphene (FNG) from expandable graphite with melamine. The super-capacitive properties of FNG were thoroughly characterized by a three-electrode system, and the results showed the FNG electrode achieved a specific capacitance as high as 83.8 mF/cm2 together with excellent cycling stability. This method could be a novel approach to combine the pseudo-capacitors and electric double layer capacitors.

For many years, experimental and theoretical studies have investigated the solubility of CO2 in a variety of ionic liquids (ILs), but the overarching absorption mechanism is still unclear. Currently, two different factors are believed to dominate the absorption performance: (a) the fractional free volume (FFV) accessible for absorption; and (b) the nature of the CO2 interactions with the anion species. The FFV is often more influential than the specific choice of the anion, but neither mechanism provides a complete picture. Herein, we have attempted to decouple these mechanisms in order to provide a more definitive molecular-level perspective of CO2 absorption in IL solvents. We simulate a series of nine different multivalent ILs comprised of imidazolium cations and sulfonate/sulfonimide anions tethered to benzene rings, along with a comprehensive analysis of the CO2 absorption and underlying molecular-level features. We find that the CO2 solubility has a very strong, linear correlation with respect to FFV, but only when comparisons are constrained to a common anion species. The choice of anion results in a fundamental remapping of the correlation between CO2 solubility and FFV. Overall, the free volume effect dominates in the ILs with smaller FFV values, while the choice of anion becomes more important in the systems with larger FFVs. Our proposed mechanistic map is intended to provide a more consistent framework for guiding further IL design for gas absorption applications.

In this study, nitrogen-doped carbon nanotubes (CNx-NTs) with a 8.4% nitrogen content were investigated under high pressure using Raman spectroscopy as well as X ray diffraction (XRD) with synchrotron radiation. For comparison purpose, high pressure behaviors of carbon nanotubes (CNTs) without nitrogen were studied as well. Two phase transformations were identified in CNx-NTs, which can be assigned to tube shape change from circular to ellipse-like and then to flatten shape. In strong contrast, no obvious phase transition was found in CNTs. In addition to the tube shape change, a high pressure M-carbon phase was also evidenced by XRD. Both CNTs and CNx-NTs showed axial dependent compressibility under high pressure. Furthermore, this study found the CNx-NTs acted more complexly than carbon in other forms such as single wall CNTs, multiwall CNTs, and graphite, suggesting the doping of nitrogen in addition to the wall thickness affect the properties of CNx-NTs under high pressure. Especially the doping of nitrogen could also help to extend the appearance of M-carbon phase to lower pressure range. Finally, the TEM images also show the retrieved CNx-NTs were partially amorphousized, which was believed due to the high pressure M-carbon phase formed at high pressure. Keywords: Nitrogen doped carbon nanotube, High pressure behaviours, Synchrotron radiation, Raman spectroscopy, Phase transformation, M-carbon phase

Designing materials with multiscale, hierarchical structure is critical to drive the advancement of new technology. Specifically, porous metals with multiscale porosity from nanometer to micrometer sizes would lead to enhanced physical and chemical properties-the micron-sized pores can increase the effective diffusivity of ion transport within the porous media, and the nano-sized pores provide high specific surface area, enabling functionalities that are unique to nanoporous metals. A new ternary precursor alloy selection concept utilizing the different mixing enthalpies is demonstrated in this work for the design of multiscale, bimodal porous copper from a simple, one-step dealloying of Cu-Fe-Al ternary alloy. The nanoporosity in the bimodal porous structure is formed from dealloying of the Cu-rich phase, whereas the microporosity is controlled by dissolving the Fe-rich phase, determined by both the initial Fe particle size and sintering profile. In addition to advancing the materials design method, the multiscale pore formation during dealloying was directly visualized and quantified via an interrupted in situ synchrotron X-ray nano-tomography. The 3D morphological analysis on tortuosity showed that the presence of the microporosity can compensate the increase of the diffusion path length due to nanoporosity, which facilitates diffusion within the porous structure. Overall the focus of the work is to introduce a new strategy to design multiscale porous metals with enhanced transport properties, and sheds light on the fundamental mechanisms on the 3D morphological evolution of the system using advanced synchrotron X-ray nano-tomography for future materials development and applications.

As major waste materials in the rice milling industry, rice husks (RHs) have potential industrial applications. In this work, acid solutions were used to extract high-value-added polysaccharide components (hemicellulose and cellulose) from RHs to obtain sugar residues (SRs) for comprehensive utilization. The SRs were converted into C/SiO2 composites after carbonization and ball-milling. The C/SiO2 composites with crystalline cellulose content in the precursor possessed desirable electrochemical properties when tested as an anode material for lithium-ion batteries (LIBs), including cycle performance, initial Coulombic efficiency (ICE) and electrical impedance. Meanwhile, a high reversible specific capacity of 553 mAh g−1 was maintained after 100 cycles at a current density of 0.1 A g−1. This method can be used to turn biomass into a potentially valuable anode material with desirable electrochemical properties for LIBs.

Traditional link prediction methods of social network are vulnerable to the influence of network structure and have poor generalization, and only on a small number of networks and evaluation indicators. To improve the stability and accuracy of link prediction, this paper assembles 15 similarity indexes, introduces the idea of stacking into the link prediction of complex networks, and presents a link prediction method (Logistic-regression LightGBM Stacking Link Prediction, LLSLP). Firstly, social network link prediction is regarded as a binary classification problem. Secondly, the hyper parameters of the basic model are determined by using cross-validation and grid searching; thirdly, Logistic-regression and LightGBM are integrated by stacked generalization; Finally, take 10 different networks as practical examples. The feasibility and effectiveness of the proposed method are verified by comparing 7 evaluation indicators. The experimental results show that: the proposed method is not only more than 98.71% higher than the traditional CN (Common Neighbor) and other models are 10.52% higher on average. In addition, compared with the traditional 15 link prediction algorithms, $F1- score$ value and $MCC$ (Matthews Correlation Coefficient) value is increased by 3.2% ~ 9.7% and 5.9% ~ 14% respectively. The proposed method has good accuracy and generalization. It can also be applied to recommendation system.

Three-dimensional bicontinuous porous materials formed by dealloying contribute significantly to various applications including catalysis, sensor development and energy storage. This work studies a method of molten salt dealloying via real-time in situ synchrotron three-dimensional X-ray nano-tomography. Quantification of morphological parameters determined that long-range diffusion is the rate-determining step for the dealloying process. The subsequent coarsening rate was primarily surface diffusion controlled, with Rayleigh instability leading to ligament pinch-off and creating isolated bubbles in ligaments, while bulk diffusion leads to a slight densification. Chemical environments characterized by X-ray absorption near edge structure spectroscopic imaging show that molten salt dealloying prevents surface oxidation of the metal. In this work, gaining a fundamental mechanistic understanding of the molten salt dealloying process in forming porous structures provides a nontoxic, tunable dealloying technique and has important implications for molten salt corrosion processes, which is one of the major challenges in molten salt reactors and concentrated solar power plants., Understanding how pores evolve in metals submerged in molten salts is important for nanofabrication technology and molten salt corrosion in nuclear and solar power plants. Here, the authors present an in situ X-ray 3D imaging to directly visualize and quantify the process.

This paper proposes a new information dissemination and opinion evolution IPNN (Information Propagation Neural Network) model based on artificial neural network. The feedforward network, feedback network and dynamic evolution algorithms are designed and implemented. Firstly, according to the ‘six degrees separation’ theory of information dissemination, a seven-layer neural network underlying framework with input layer, propagation layer and termination layer is constructed; secondly, the information sharing and information interaction evolution process between nodes are described by using the event information forward propagation algorithm, opinion difference reverse propagation algorithm; finally, the external factors of online social network information dissemination is considered, the impact of external behavior patterns is measured by media public opinion guidance and network structure dynamic update operations. Simulation results show that the proposed new mathematical model reveals the relationship between the state of micro-network nodes and the evolution of macro-network public opinion. It accurately depicts the internal information interaction mechanism and diffusion mechanism in online social network. Furthermore, it reveals the process of network public opinion formation and the nature of public opinion explosion in online social network. It provides a new scientific method and research approach for the study of social network public opinion evolution.

Tumor microenvironment (TME)-responsive nanosystems represent a category of intelligent nanomaterials for precise anticancer drug delivery. Herein, we report a smart size-/morphology-switchable nanodrug that can respond to the acidic TME and near-infrared (NIR) laser irradiation for effective tumor ablation and tumor metastasis inhibition. The nanoagent is physically assembled by a cytolytic peptide, melittin (MEL), an NIR-absorbing molecule, cypate, and a tumor-targeting polymer, hyaluronic acid (HA). At pH 7.4, the as-formed MEL/Cypate@HA complexes are negatively charged nanospheres (∼50 nm), which are suitable for long-term systemic circulation. When these nanospheres actively target tumors, the weakly acidic TME triggers an

Mining activities are among the main sources of heavy metal contamination in the environment. To analyze heavy metal pollution of soils from coal mines in China, we assessed pollution and potential ecological risk, compared heavy metal concentrations between soils from coal mines and soils from metal mines and identified the relationship between heavy metals on the nationwide scale. The data of heavy metal concentrations for 50 coal mines and 35 metal mines were collected from the published literature. Coal mines referred in this paper are distributed in 18 provinces and 4 climatic zones in China. Methods including Index of geoaccumulation (Igeo), Nemerow pollution index (P), potential ecological risk index and other statistics (Pearson correlation method and ANOVA variance analysis) were utilized. Compared with soils influenced by metal mining, heavy metal concentrations in soils from coal mines were much lower. For heavy metals, higher Igeo for Cd, Pb and Ni was observed. Soils were contaminated or slightly contaminated when calculated based on Chinese soil guidelines (grade I and grade II) but slightly contaminated or severely contaminated when calculated based on province backgrounds. Most heavy metals (i.e., As, Cr, Cu, Ni and Zn) showed a low potential ecological risk, whereas Cd, Pb and Hg showed slightly higher ecological risk potential. Statistically significant and positive correlations were found in pairs of As/Cr, As/Ni, As/Pb, As/Hg, Ni/Cr and Ni/Cu (P

Propylene epoxidation using molecular oxygen and hydrogen mixture on Au-based catalysts has attracted attention because of high propylene oxide selectivity and the use of an inexpensive and environmental friendly oxidant. Single-site titanium on metal oxide supports plays an important role in achieving high reactivity and selectivity in propylene epoxidation. Here we used TiO2 atomic layer deposition (ALD) to synthesize single-site titanium imbedded in the SiO2 framework for propylene epoxidation. High temperature calcination was used as post-treatment to control the titania structure and Ti O coordination number. Using UV–vis spectroscopy and X-ray absorption spectroscopy, we successfully established that under similar propylene conversion the selectivity to propylene oxide (PO) is strongly correlated to the Ti O coordination number and bond length. Using a cluster model, density functional theory (DFT) calculations indicate that the partial charges of single Ti SiO2 sites scale linearly as a function of the coordination number. Also, the predicted Ti O bond lengths follow the same trend as found in the experiments, providing additional support for the observed experimental activity relationships.

The interfacial hydrolysis of phospholipids catalyzed by phospholipase A1 (PLA1) was studied via sum frequency generation (SFG) vibrational spectroscopy and fluorescence microscopy. Both monolayer and bilayer setups were used to confirm the hydrolysis mechanism. During the hydrolysis, lysophospholipids, one of the hydrolysis products, were desorbed from the interface into the solution, while the other products, fatty acids, self-organized and accumulated with PLA1 at the interface to form the PLA1-induced regions, which can serve as nonspecific binding domains for proteins and thus lead to human vascular diseases. This experimental study provides the essential information on revealing the interfacial biochemical process related to the metabolism of the lipids, which is one of the basic building blocks for cells.

One major challenge in the commercialization of halide perovskite solar cells is the device instability against moisture. Efficient perovskite solar cells usually incorporate the ionic dopants within the charge transfer material to secure their electrical conductivity. Typical ionic dopants are hygroscopic, resulting in significant moisture adsorption and accelerated perovskite degradation. Herein, we report a nonionic dopant, Sc3N@C80, consisting of a hydrophobic fullerene cage that encapsulates the metal salt to achieve a moisture resistive and highly electrically conductive hole transfer layer (HTL). The direct electronic transaction between Sc3N@C80 and spiro-OMeTAD renders a drastically improved conductivity and a lower Fermi-level of the HTL to minimize the Schottky barrier. The hydrophobicity of Sc3N@C80 also decreases the moisture wettability. Perovskite solar cells using the Sc3N@C80-doped HTL exhibit an efficiency surge from 18.15 to 20.77% (champion cell exhibiting 21.09%) and improved device s...

This study demonstrated increases in the recovery of phenolic compounds from industrial waste, longan peel, after treatment with plant matrix degrading enzymes. Pretreatment of longan peel with cellulase, α-amylase, protease, or β-glucosidase enhanced total phenolic content in the extracts, leading to increases of DPPH scavenging activity, oxygen radical absorbance capacity, antioxidant in β-carotene/linoleate system, and ferrous ion chelating activity. In detail, cellulase increased the release of free phenolics e.g. o-coumaric acid, corilagin, and quercetin as well as the release of esterified phenolics e.g. ellagic acid, and gallic acid, while β-glucosidase increased the release of free phenolics e.g. ellagic acid. Among all enzymatic pretreatments, protease provided the highest proportion of phenolics’ recovery in the extract, while only cellulase and β-glucosidase significantly improved extraction yields by 31 and 17%, respectively. These results indicated enhancement of valorization of longan peel as a resource material for functional ingredients recovery.

Development of the synthesis methods of rice husk-based activated carbon (AC) as electrode materials by utilizing the natural silica template effect has been of special interests for high quality electrode material design. To enhance the silica template efficiency, a selective leaching out of the useless silica exposed on sample surface using NaOH solution at a moderate condition was adopted. The actual silica template located within the sample could be preserved and work with alkali activators to open the firm carbon texture, offer more active sites for pore generation, and therefore could improve the specific capacitance. The electrochemical performance of the prepared AC products was thoroughly characterized and a high specific capacitance together with extraordinary cycling stability was observed. This strategy offered an applicable way to facilitate industrial synthesis of high quality AC based electrodes for advanced supercapacitors.

In this work, we demonstrated the synthesis of amino functionalized MWNTs (af-MWNTs) via a simple and facile hydrothermal process and the af-MWNTs was acted as the hole transport layers (HTLs) of polymer solar cells (PSCs) based on active layers of Poly[N‑9″‑hepta‑decanyl‑2,7‑carbazolealt‑5,5‑(4′,7′‑di‑2‑thienyl‑2′,1′,3′‑benzothiadiazole)] (PCDTBT) and fullerene derivative [6,6]‑phenyl‑C71‑butyric acid methylester (PC71BM). Comparing with the control devices, devices based on af-MWNTs HLTs achieved an optimal power conversion efficiency (PCE) of 6.970%, leading to 17.6% enhancement comparing to the control device. The af-MWNTs HTLs exhibited remarkable enhancement on electrical conductivity, which was beneficial to the hole extraction and transport on interface. The enhancement of PCE was mainly attributed to the superior hole transport and extraction capabilities. Meanwhile, the af-MWNTs exhibited a suitable work function (WF) which was beneficial to hole extraction from the photoactive layer to the ITO anode. The experimental results indicated that the af-MWNTs HTLs not only presented excellent optical and electrical properties, but also played an important role for improving the efficiency of PSCs.

Recently, metal molybdates have drawn significant attention due to their excellent electrochemical properties and remarkable performances in various fields, especially for supercapacitors. The rod-like α-MnMoO4 crystallites were designed and synthesized via a microwave-assisted hydrothermal process followed by annealing and used as electrode materials for supercapacitors. The effects of different microwave reaction time on the electrochemical properties of samples were investigated. The formation of nanorods and the microwave heating mechanism involved were introduced. Thorough characterization of the electrochemical properties was performed, and the results demonstrated the extraordinary supercapacitor properties with a high specific capacitance (446.7 F g−1 at current densities of 1 mA cm−2), excellent rate capability, and superior cycling stability (81.12% retained after 3000 cycles at 8 mA cm−2). This work provided a rapid, facile, and environment-friendly strategy for active molybdates material synthesis and outlined the superior electrochemical properties of rod-like α-MnMoO4 crystallites and its great potential in supercapacitor applications.

It was recently recognized that two-dimensional (2D) graphene exhibits nonplanar aberrations such as a rippled surface. Understanding the self-assembly of organic semiconductor molecules on monolayer 2D curved graphene surfaces is a paramount issue for ultimate application in semiconductor and optoelectronic devices. Herein, we report on the preparation of fullerene, C60 and perylenetetracarboxylic dianhydride (PTCDA) molecules adsorbed on a rippled graphene surface. We find that the spherical C60 molecules form a quasi-hexagonal close packed (hcp) structure, while the planar PTCDA molecules form a disordered herringbone structure. These 2D layer systems have been characterized by experimental scanning tunneling microscope (STM) imaging and computational density functional theory (DFT) approaches. The DFT computational results exhibit interaction energies for adsorbed molecule/rippled graphene complexes located in the 2D graphene valley sites that are significantly larger in comparison with adsorbed idealized planar/molecule graphene 2D complexes. In addition, we report that the adsorbed PTCDA molecules prefer different orientations when the rippled graphene peak regions are compared to the valley regions. This difference in orientations causes the PTCDA molecules to form a disordered herringbone structure on the rippled graphene surface. The results of this study clearly illustrate significant differences in C60 and PTCDA molecular packing on rippled graphene surfaces.

In the present study, two types of nanostructured electrodes consisting of ZnCo2O4 nanowire arrays (NWAs) and ZnCo2O4 nanosheet arrays (NSAs) were successfully synthesized through a facile hydrothermal method followed by an annealing treatment. The ZnCo2O4 NWAs electrode exhibited a high specific capacitance of 2049 F g−1 at 2 mA cm−2 and an excellent rate capability of 83.6% as the current density was increased from 2 to 30 mA cm−2. Moreover, the cycling stability of ZnCo2O4 could retain 88.8% capacitance retention after 3000 cycles at a high current density of 10 mA cm−2. The ZnCo2O4 NSAs delivered a specific capacitance of 1159 F g−1 at 2 mA cm−2 and a long-term cycling performance of 79.9% capacitance retention. An asymmetric supercapacitor (ASC) was assembled using ZCO-1 NWAs and activated carbon (AC) as the positive and negative electrodes, respectively, and the optimized ASC cell delivered a high energy density of 37.5 W h kg−1 at a power density of 358.2 W kg−1. The excellent electrochemical performance of ZnCo2O4 NWAs electrode implied that such electrode could be effectively used in supercapacitors (SCs).

A nonlinear dynamic emergency public event information diffusion system and mathematical model for public events are proposed based on the propagation dynamics. First, public emergency information communication is analyzed and designed, the opinion evolution is divided into and the viewpoint of value, influence, interest, conformity, intimacy five factors of information diffusion for public emergencies; second, the dynamic diffusion network is designed; information propagation mathematical public emergencies the final model is constructed; the proposed model and social reality and the true statistics of empirical experiments are simulated and analyzed. The experimental results show that the model and the real emergency public event propagation process are consistent, the development trend can predict public events, and the proposed mathematical model is reasonable and effective.

The synthesis of Ag nanoparticles (AgNPs) frequently requires the participation of organic ligands. However, how the organic ligands attached on their surfaces would affect the antibacterial activity of the AgNPs remains to be explored. Based on a novel in situ synthesis approach, silica supported AgNPs with bare surfaces were fabricated and further functionalized with different organic ligands (–OH, –Ph, –SH, and –COOH) and the antibacterial activities of the bare AgNPs and AgNPs with different ligands were investigated. Though all specimens exhibited different antibacterial capabilities against Escherichia coli (E. coli), the minimal inhibitory concentration (MIC) of AgNPs functionalized with –COOH was the smallest and as low as 8–16 μg ml−1, indicating the best antibacterial performance among the 4 ligands. In addition, the cytotoxicity test of the bare AgNPs and AgNPs with ligands indicated that all the AgNPs caused no significant damage to human cells, suggesting their good potential for antibacterial applications in daily life.

Imaging the dynamics and behaviors of plasma membranes is at the leading edge of life science research. We report here the development of a universal red-fluorescent probe Chol-PEG-Cy5 for wash-free plasma membrane labelling both in vitro and in vivo. In aqueous solutions, the fluorescence of Chol-PEG-Cy5 is significantly quenched due to the intermolecular resonance energy transfer (RET) between neighbouring Cy5 moieties; however, upon membrane anchoring, the probes undergo lateral diffusion in lipid bilayers, resulting in weakened RET and turn-on fluorescence emission. We demonstrate that Chol-PEG-Cy5 enables rapid, stable and high-quality in vitro cell surface imaging in a variety of mammalian cells. Additionally, with the assistance of three-dimensional (3D) image reconstruction, we achieve for the first time the whole-mount in situ fluorescence imaging of the epidermal cell surfaces of live zebrafish embryos, which cannot be realized by conventional plasma membrane probes due to the presence of the surface-covering mucus barrier. This novel technique encourages us to track the cellular dynamics of the epidermis during embryonic development with 3D visualization. Moreover, we also develop a new method to evaluate the epidermal toxicity of nanomaterials (e.g., gold nanoparticles and graphene oxide nanosheets) toward zebrafish embryos using this fluorescent probe.

The skins of most mature apple fruits are incompletely red and also include green and pale yellow color, which increases the difficulty of fruit detection by machine vision. A detection method based on color and shape features is proposed for this kind of apple fruits. Simple linear iterative clustering (SLIC) is adapted to segment images taken in orchards into super-pixel blocks. The color feature extracted from blocks is used to determine candidate regions, which can filter a large proportion of non-fruit blocks and improve detection precision. Next, the histogram of oriented gradient (HOG) is adopted to describe the shape of fruits, which is applied to detect fruits in candidate regions and locate the position of fruits further. The proposed method was tested by images taken under different illuminations. The average values of recall, precision, and F1 reach 89.80%, 95.12%, and 92.38% respectively. The performance of detecting fruits covered at different levels is also tested. The values of the recall are all more than 85%, which indicates that proposed method can detect a great part of covered fruits. Compared with pedestrian detection method and faster region-based convolutional neural network (RCNN), the proposed method has the best performance and higher than faster RCNN slightly. However, the proposed method is not robust to noise and its elapsed time of one image is 1.94 s and less than faster RCNN.

So as to accelerate the resuscitation of starved anaerobic granular sludge after long-term stagnation, an innovative method was tried derived from the regulation of N-acyl-homoserine lactones (AHLs)-mediated quorum sensing (QS). The mixture of four AHLs was added to the starved anaerobic granular sludge system in this research. The results confirmed that the exogenous AHLs shortened the recovery time of the granular sludge, and improved the treatment performance and methanogenic capacity of the recovered anaerobic sludge to the level before stagnation. At the same time, exogenous AHLs enhanced the synthesis of extracellular polymeric substances (EPS) during the resuscitation period of starved anaerobic granular sludge. The outcomes of microbial composition detection showed that the change of bacterial and methanogenic bacteria communities towards accelerated performance recovery was significantly correlated with exogenous AHLs. This exploration provided a new technical idea for speeding up the recovery of starved anaerobic granular sludge.

A N-enriched porous carbon/SiO2 (SiO2 /NC) composite from rice husks was prepared by ball milling and tested as a stable anode for lithium ion batteries (LIBs), in which the homogeneous dispersion of SiO2 nanoparticles and carbon matrix, and high level of N-doping can be realized simultaneously. The influence of N-doping on a series of SiO2 /NCs was systematically studied; this proved that the porosity, N-doping content, and electronic conductivity of SiO2 /NC can be controlled by adjusting common nitrogen sources (urea and melamine) and doping routes, including dry and wet milling, to reach a desirable balance of high capacity, long-term cyclability, and rate property. The optimized SiO2 /NC composite delivers a stably reversible capacity of 581 mA h g-1 at the high current load of 1.0 A g-1 at the 1000th cycle. The novel Li-storage mechanism of active silica in a composite was first proposed after observation of the N-doping effect that the redox reaction between SiO2 and Li+ is accelerated to transform into an alloying reaction of generated Si and Li+ , thus enhancing the reversible capacity. Moreover, kinetics analysis confirms that there is a combined Li-storage mechanism of battery-capacitive pattern in composite that contributes to fast charge transfer and ion diffusion during cycle.

Positron-emission tomography (PET) imaging enables cancer diagnosis at an early stage and to determine its pathological degree. However, tumor uptake efficiency of traditional PET radiotracers is usually low. Herein, we rationally designed a precursor CBT-NODA, the cold analogue CBT-NODA-Ga, and its corresponding radiotracer CBT-NODA-68Ga. Using these three compounds, we verified that coinjection of CBT-NODA-68Ga with CBT-NODA or CBT-NODA-Ga could lead to the synthesis of hybrid gallium-68 nanoparticles in furin-overexpressing cancer cells and enhance microPET tumor imaging in mice. In vivo experiments showed that coinjection of CBT-NODA-68Ga with CBT-NODA-Ga had the most prolonged retention of the radiotracer in blood, the highest radioactivity in tumor regions, and the most enhanced microPET tumor imaging in mice. We anticipate that, by combining the coinjection strategy with our CBT-Cys click condensation reaction, more radiotracers are developed for microPET imaging of more tumors in clinical settings in the future.

Corrosion protection is of great importance, since corrosion on metals and alloys happens in a wide range of applications and causes economic and environmental issues. Among various corrosion protection methods, chemical conversion coatings applied by a simple solution immersion process on different metals as a pretreatment has great advantages. The technique is easy to operate and economic. The resulting conversion coatings then act as an effective barrier to corrosion, as well as improving the adhesion between the metal/alloy substrate and the subsequent organic coating. As conventional chromate and phosphate conversion coating treatment has health and environmental issues, there is a strong motivation to develop novel environmentally friendly chemical conversion coatings with comparable functionality. Specifically, zirconium-based (Zr-based) conversion coatings created by immersing alloy substrates in hexafluorozirconic acid (H2ZrF6) solution is an outstanding candidate because of its lower operational cost and fast deposition, while offering good anti-corrosion and adhesion properties.1 Prior works of Zr-based conversion coatings have been focusing on further improving their anti-corrosion performance by controlling the coating deposition parameters including temperature, time, pH value and incorporating organic (silane, phosphonic acids) or inorganic (copper, cerium) compounds. In this study, a novel organic-inorganic hybrid Zr-based conversion coating with copper (Cu) and polyamidoamine (PAMAM).2 Incorporating organic component PAMAM has been shown to enhance the corrosion resistance of the conversion coating, as well as to provide binding media for the subsequent paint coating. Despite evidence showing superior performance, the film growth and reaction mechanisms of the hybrid conversion coatings, when incorporating these additives, is not well understood. Here, we studied the effect of the additive PAMAM concentration in the coating solution on the morphology, structure and chemical composition of the coating by a multimodal X-ray and electron analysis. First, we discovered an inverse relationship between the concentration of PAMAM and the thickness of the coating. A higher PAMAM concentration was also found to reduce the Cu-containing cluster formation. Elemental distribution analysis by Scanning Transmission Electron Microscopy with Energy-dispersive X-ray Spectroscopy revealed different microstructure in the surface cluster formation; Cu-containing nanoparticles formed in coatings without PAMAM additives, whereas a more homogenous distribution of Cu species was found in samples with PAMAM. The atomic ratio of elements characterized by X-ray Photoelectron Spectroscopy (XPS) varied with coating conditions. Notably a higher ratio of organic elements indicated the incorporation of PAMAM into the conversion coating with possibly some further adsorption. High-resolution XPS revealed the existence of amide and amine in the coating and different oxidation states of Cu; the results indicate that the reduction reaction of the Cu ions was suppressed by PAMAM, because the complexation between Cu and PAMAM decreased the reduction potential of Cu. In addition, the corrosion of the hybrid coatings in alkaline environment was characterized by synchrotron X-ray Absorption Near Edge Structure (XANES) Spectroscopy showing a better corrosion resistance of hybrid coating with less dissolution of clusters. Overall, the study discussed the interaction between Cu ions and PAMAM and the subsequent effect on the coating morphology and composition as well as the anti-corrosion property. The work furthers the fundamental understanding on how organic and inorganic additives may synergistically act to enhance the properties of the conversion coating. We intend to shed light on the critical processing-structure-property relationship that need be considered and tailored for applying and designing novel conversion coatings for corrosion protection applications. Figure caption: Surface (top row) and cross-sectional morphology (bottom row) of the conversion coatings with 0 to 200 ppm PAMAM concentration in the coating solution. From the surface view, the cluster visually decreases with increase of PAMAM concentration. The flake-like morphology could be observed on sample with higher PAMAM concentration. From the cross-sectional view, the voids and thickness of the coating decreases with increasing PAMAM concentration. Reference: (1) Xiaoyang Liu, D. V., Hua Jiang, Kim Kisslinger, Xiao Tong, Mingyuan Ge, Evgeny Nazaretski, Bruce Ravel, Kate Foster, Stanislas Petrash, Yu-chen Karen Chen-Wiegart. Environmentally Friendly Zr-Based Conversion Nanocoatings for Corrosion Inhibition of Metal Surfaces Evaluated by Multimodal X-ray Analysis. ACS Appl. Nano Mater. 2019, DOI: 10.1021/acsanm.8b02309. (2) Donald Robb Vonk, T. S. S., Alvaro Bobadilla Thin Corrosion Protective Coatings Incorporating Polyamidoamine Polymers. Feb. 8, 2018. Figure 1

Organic-inorganic hybrid materials like bone, shells, and teeth can be found in nature, which are usually composed of biomacromolecules and nanoscale inorganic ingredients. Synergy of organic-inorganic components in hybrid materials render them outstanding and versatile performance. Chitosan is commonly used organic materials in bionic hybrid materials since its bioactive properties and could be controllable tailored by various means to meet complex conditions in different applications. Among these fabrication means, hybridization was favored for its convenience and efficiency. This review discusses three kinds of chitosan-based hybrid materials: hybridized with hydroxyapatite, calcium carbonate, and clay respectively, which are the representative of phosphate, carbonate, and hydrous aluminosilicates. Here, we reported the latest developments of the preparation methods, composition, structure and applications of these bioactive hybrid materials, especially in the biomedical field. Despite the great progress was made in bioactive organic-inorganic hybrid materials based on chitosan, some challenges and specific directions are still proposed for future development in this review.

Water resources are important for agricultural, industrial, and urban development. In this paper, we analyzed the influence of rainfall and snowfall on variations in terrestrial water storage (TWS) in Northeast China from Gravity Recovery and Climate Experiment (GRACE) gravity satellite data, GlobSnow snow water equivalent product, and ERA5-land monthly total precipitation, snowfall, and snow depth data. This study revealed the main composition and variation characteristics of TWS in Northeast China. We found that GRACE provided an effective method for monitoring large areas of stable seasonal snow cover and variations in TWS in Northeast China at both seasonal and interannual scales. On the seasonal scale, although summer rainfall was 10 times greater than winter snowfall, the terrestrial water storage in Northeast China peaked in winter, and summer rainfall brought about only a sub-peak, 1 month later than the maximum rainfall. On the interannual scale, TWS in Northeast China was controlled by rainfall. The correlation analysis results revealed that the annual fluctuations of TWS and rainfall in Northeast China appear to be influenced by ENSO (EI Niño–Southern Oscillation) events with a lag of 2–3 years. In addition, this study proposed a reconstruction model for the interannual variation in TWS in Northeast China from 2003 to 2016 on the basis of the contemporary terrestrial water storage and rainfall data.

One of the greatest challenges in developing SiO 2/C composites as anode materials in lithium ion batteries (LIBs) is to improve the ability of Li storage at high rate over long-term cycles. Herein, biomass rice husks-based hierarchically porous SiO 2/N-doped carbon composites (BM-RH-SiO 2/NC) were prepared by ball mill and thermal treatment. BM-RH-SiO 2/NC can still retain a reversible capacity of 556 mAh g −1 over 1000 cycles at a high current of 1.0 A g −1. At 5.0 A g −1 the capacity is kept as high as 402 mAh g −1. This impressively long-term cyclic performance and high-rate capability of BM-RH-SiO 2/NC can be ascribed to the synergetic effect between the natural SiO 2 nanoparticles (< 50 nm) and the NC layer. The coating NC layer can not only effectively mitigate the volume strain during charge-discharge process to offer stably cyclic performance but also improve the electrical conductivity. Furthermore, the hierarchical porosity and better electrolyte wettability offer the rapid Li + diffusion and electron transfer, which enhance the pseudocapacitive behavior of whole electrode material and then guarantee fast electrochemical kinetics. Importantly, the unique Li-storage mechanism of active SiO 2 in BM-RH-SiO 2/NC composite was formed and found, which further validates the improved electrochemical capability.

In recent decades, the ecological security pattern (ESP) has drawn increasing scientific attention against the backdrop of rapid urbanization and worsening ecological environment. Despite numerous achievements in identifying and constructing the ecological security pattern, limited attention has been paid on applying ESP to predict urban growth. To bridge the research gap, this paper took Quanzhou, China as a study case and incorporated the identified ESP into an urban growth simulation with three distinct scenarios. Following the &ldquo, ecological source&ndash, ecological corridor&ndash, ecological security pattern&rdquo, paradigm, the ESP identification was carried out from four single aspects (i.e., water, geology, biodiversity, and recreation) into three levels (i.e., basic ESP, intermediate ESP, and optimal ESP). Grounded in an equally weighted superposition algorithm, the four single ESPs were combined as an integrated ESP (IESP) with three levels. Taking IESP as an exclusion element, urban growth simulation in 2030 was completed with thee SLEUTH model. Drawing on the three levels of IESP, our urban growth simulation contained three scenarios. In terms of urban sprawl distribution coupled with urban growth rate, an optimal urban growth scenario is recommended in this paper to balance both urban development and eco-environment protection. We argue that our ESP-based urban growth simulation results shed new light on predicting urban sprawl and have the potential to inform planners and policymakers to contribute to more environmentally-friendly urban development.

Coal fire hazards not only causes loss of coal resources but also induces serious geological hazards and environmental degeneration. Wuda Coalfield (China), known for its widespread coal fires, was used as the study area for this study. Owing to an inherent noise problem, CBERS (China & Brazil Earth Resource Satellite)-04 thermal infrared images have not been explored and applied in the field of coal fire detection. An adaptive-edge-threshold (AET) method was proposed to delineate coal fire maps based on nighttime CBERS-04 data from 2015 to 2020. Iterative Self-Organizing Data Analysis Technique Algorithm (ISODATA) was employed to cluster coal fire spots into different classes, then coal fire propagation directions were generated by connecting the clustering centers of the same class in chronological order. The results of quantitative analysis of coal fires showed that AET method achieved the highest accuracy among four coal fire recognition algorithms; the accuracy of AET in field verification reached 81.25%. The total area of coal fires increased by 137%, while the total intensity of coal fires decreased by 18% from 2015 to 2020. Overall accuracies of ISODATA clustering coal fire spots were between 90.25% and 100.00%, the Kappa coefficients were between 0.82 and 1.00. The evolution trend of coal fires obtained based on this clustering accuracy is reliable. The evolution trend of coal fires is as follows: coal fires of Class I spread to the northwest; coal fires of Class II first propagated to the northwest, then to the south and then to the west; coal fires of Class III essentially stayed in the same place; coal fires of Class IV spread to the northwest; coal fires of Class V spread to the southeast and then to the northeast.

Due to rapid urbanization, industrialization, agricultural development, and mining activities, soil heavy metal pollution has become a severe issue in China. To explore the regional heavy metal ecological risk of lake sediment and surrounding topsoil, we analyzed 237 lakes, with 1797 lake sediment sampling points and 1164 surrounding topsoil sampling points. Lower mean concentrations were detected for most heavy metals in soils than sediment (except for Hg). Cd and Hg in sediments and soils showed a more significant variation, with the coefficient of variation exceeding 110%. Linear regressions and Pearson's correlation analyses demonstrated that sediments and soils exhibited significant positive correlations. The principal heavy metals exceeding the Agricultural Soil Control Standard (ASCS) in sediments and soils were As and Cd, respectively. The Yunnan-Guizhou Plateau Lake Region (YGPLR) was the most seriously affected, exceeding the ASCS for Cd. The lakes with the most severe pollution were located in YGPLR impacted by the high background concentration of heavy metals in soil and mineral development activities. The Eastern Plain Lake Region, the Southeast Lake Region, and the Northeast Plain and Mountain Lake Region showed a clear anthropogenic impact. Lakes in the Inner Mongolia-Xinjiang Lake Region and the Tibetan Plateau Lake Region were estimated to have relatively low ecological risks due to their sparse population and slight environmental disturbance. The impact of geochemical factors on the ecological risk of heavy metals in lake sediments is more substantial than that of human activities at the regional scale.

The quantitative evaluation of the three-dimensional (3D) morphology of porous composite materials is important for understanding mass transport phenomena, which further impact their functionalities and durability. Reactive porous paint materials are composites in nature and widely used in arts and technological applications. In artistic oil paintings, ambient moisture and water and organic solvents used in conservation treatments are known to trigger multiple physical and chemical degradation processes; however, there is no complete physical model that can quantitatively describe their transport in the paint films. In the present study, model oil paints with lead white (2PbCO3·Pb(OH)2) and zinc white (ZnO) pigments, which are frequently found in artistic oil paintings and are associated with the widespread heavy metal soap deterioration, were studied using synchrotron X-ray nano-tomography and unilateral nuclear magnetic resonance. This study aims to establish a relationship among the paints’ compositions, the 3D morphological properties and degradation. This connection is crucial for establishing reliable models that can predict transport properties of solvents used in conservation treatments and of species involved in deterioration reactions, such as soap formation.

In the present study, in order to elucidate geometrical features dominating deformation behaviors and their associated compressive properties of lattice structures, AlSi10Mg lattice structures with three different unit cells were fabricated by laser powder bed fusion. Compressive properties were examined by compression and indentation tests, micro X-ray computed tomography (CT), together with finite element analysis. The truncated octahedron- unit cell (TO) lattice structures exhibited highest stiffness and plateau stress among the studied lattice structures. The body centered cubic-unit cell (BCC) and TO lattice structures experienced the formation of shear bands with stress drops, while the hexagon-unit cell (Hexa) lattice structure behaved in a continuous deformation and flat plateau region. The Hexa lattice structure densified at a smaller strain than the BCC and TO lattice structures, due to high density of the struts in the compressive direction. Static and high-speed indentation tests revealed that the TO and Hexa exhibited slight strain rate dependence of the compressive strength, whereas the BCC lattice structure showed a large strain rate dependence. Among the lattice structures in the present study, the TO lattice exhibited the highest energy absorption capacity comparable to previously reported titanium alloy lattice structures.

A greenhouse pot trial was conducted to investigate the effect of organic amendments combined with triple superphosphate on the bioavailability of heavy metals (HMs), Amorpha fruticosa growth and metal uptake from Pb-Zn mine tailings. Cattle manure compost (CMC), spent mushroom compost (SMC) and agricultural field soil (AFS) were applied to tailings at 5%, 10%, 20% and 30% w/w ratio, whereas sewage sludge (SS) and wood biochar (WB) were mixed at 2.5%, 5%, 10% and 20% w/w ratio. Triple superphosphate (TSP) was added to all the treatments at 4:1 (molar ratio). Amendments efficiently decreased DTPA-extracted Pb, Zn, Cd and Cu in treatments. Chlorophyll contents and shoot and root dry biomass significantly (p&lt, 0.05) increased in the treatments of CMC (except T4 for chlorophyll b) and SMC, whereas treatments of SS (except T1 for chlorophyll a and b), WB and AFS (except T4 for chlorophyll a and b) did not show positive effects as compared to CK1. Bioconcentration factor (BCF) and translocation factor (TF) values in plant tissues were below 1 for most treatments. In amended treatments, soluble protein content increased, phenylalanine ammonialyase (PAL) and polyphenol oxidase (PPO) decreased, and catalase (CAT) activity showed varied results as compared to CK1 and CK2. Results suggested that A. fruticosa can be a potential metal phytostabilizer and use of CMC or SMC in combination with TSP are more effective than other combinations for the in situ stabilization of Pb-Zn mine tailings.

Although soil quality can be highly altered by mining activities, there are few reports on soil pollution in mining cities. We systematically characterized the heavy metals (HMs) pollution, risks, sources, and influencing factors in the surrounding soils of Shuozhou. Specifically, 146 samples were collected, and the potential ecological risk index (RI) and the single-factor index were jointly used to understand the environmental risk of HMs. Meanwhile, correlation analysis was applied to find the influencing factors of HMs. The results of the soil pollution risk assessment in the entire area of Shuozhou were compared with those in the open-pit mine area. (1) The mean concentrations of Cr, As, Cd, Pb, and Hg in our study were found to be higher than the background value. The RI results indicated that most soil samples (82.88%) in Shuozhou had a low potential ecological risk. Compared with the Pingshuo open-pit mine (average RI value: 200.07), the potential ecological RI was lower. (2) The HM correlation indicated that Cr and As were associated with the parent rock, whereas Cd, together with Hg and Pb, were associated with anthropic activities. (3) There was no significant correlation between HM concentrations and farmland slope. Located in the Datong Basin, the terrain of Shuozhou is relatively flat and open and has little impact on the distribution of HMs. (4) Only Hg and Pb have a negative correlation with pH. This suggests that soil with a lower pH value may be beneficial to the accumulation of Hg and Pb in soil. (5) Among the eight industry types examined, the pollution capacity level of the leather, fur, feather, and footwear industries is the strongest, indicating that HMs around LI industry sites represent the maximum level among the eight types.