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Along with the extensive application of energy storage devices, the spent lithium-ion batteries (LIBs) are unquestionably classified into the secondary resources due to its high content of several valuable metals. However, current recycling methods have the main drawback to their tedious process, especially the purification and separation process. Herein, we propose a simplified process to recycle both cathode (LiCoO2) and anode (graphite) in the spent LIBs and regenerate newly high-performance anode material, CoO/CoFe2O4/expanded graphite (EG). This process not only has the advantages of succinct procedure and easy control of reaction conditions, but also effectively separates and recycles lithium from transition metals. The 98.43% of lithium is recovered from leachate when the solid product CoO/CoFe2O4/EG is synthesized as anode material for LIBs. And the product exhibits improved cyclic stability (890 mAh g−1 at 1 A g−1 after 700 cycles) and superior rate capability (208 mAh g−1 at 5 A g−1). The merit of this delicate recycling design can be summarized as three aspects: the utilization of Fe impurity in waste LiCoO2, the transformation of waste graphite to EG, and the regeneration of anode material. This approach properly recycles the valuable components of spent LIBs, which introduces an insight into the future recycling.

A digital microfluidic system based on electrowetting-on-dielectric is a new technology for controlling microliter-sized droplets on a plane. By applying a voltage signal to an electrode, the droplets can be controlled to move, merge, and split. Due to device design, fabrication, and runtime uncertainties, feedback control schemes are necessary to ensure the reliability and accuracy of a digital microfluidic system for practical application. The premise of feedback is to obtain accurate droplet position information. Therefore, there is a strong need to develop a digital microfluidics system integrated with driving, position, and feedback functions for different areas of study. In this article, we propose a driving and feedback scheme based on machine vision for the digital microfluidics system. A series of experiments including droplet motion, merging, status detection, and self-adaption are performed to evaluate the feasibility and the reliability of the proposed scheme. The experimental results show that the proposed scheme can accurately locate multiple droplets and improve the success rate of different applications. Furthermore, the proposed scheme provides an experimental platform for scientists who focused on the digital microfluidics system.

Combined whole-rock geochemistry, zircon U–Pb dating, and Sr–Nd–Pb isotopic analyses were carried out to constrain the petrogenesis and tectonic implications of the “Zaranda Older Granites” (ZOG) and “Younger Granites” (ZYG) in north-central Nigeria. Zircon U–Pb dating yielded 633 ± 3 Ma for the ZOG and 203 ± 1 Ma for the ZYG, corresponding to Late Neoproterozoic and Late Triassic, respectively. The ZOG consists dominantly of biotite granite, which displays a whole-rock ɛNd(t) values of − 3.48 to − 5.00 and Nd model ages of 1620–1720 Ma. Most ZOG samples exhibit elevated Sr/Y (107–128) and La/Yb ratios (36–40), with a positive Eu anomaly (Eu/Eu* = 2.2–2.58), interpreted to reflect magma derivation through partial melting of a thickened lower crust. The ZOG is geochemically and geochronologically similar to the Pan-African granites from Togo–Benin (West Africa) and Northeast Borborema, Sao Paulo (Brazil), suggesting that their emplacement probably marked the initial phase of the Pan-African orogeny during which the Gondwana was amalgamated. The ZYG consists of compositionally diverse alkaline granitoids including aegirine syenites, quartz syenite, and fayalite granite porphyry. These rocks are strongly ferroan, alkalic and show petrographic and geochemical features of classical A-type granites. Substantial depletion in Ba, Sr, P, Ti, and Eu signifies fractionation of felsic and mafic minerals such as feldspar, biotite, amphibole, and Ti-rich augite. The low Y/Nb and Yb/Ta ratios (≤ 2) indicate that the ZYG samples display geochemical features typical of OIB-derived A-type granites. The ɛNd(t) values in the ZYG range from + 4.16 to − 2.76 and the Nd model ages range from 0.6 to 1.2 Ga. Based on these results, we propose that the ZYG samples and by extension, other alkaline granitoids from the Nigerian Younger Granite (NYG) province with similar geochemical compositions were likely generated through extensive differentiation of OIB-type mantle-derived magma. The concentrations of Nb and other HFSEs are much higher in ZYG than ZOG, indicating that the former has higher rare metal mineralization potential.

Solution-processed organic light-emitting diodes (OLEDs) are much preferred for the manufacture of low-temperature, low-cost, large-area, and flexible lighting and displaying devices. However, these devices with high external quantum efficiency are still limited, especially for blue ones. In addition, the molecular configurations of emitters are usually complicated, indicative of high costs. In this study, two simple-structured thermally activated delayed fluorescent emitters M1 and its polymer P1 were synthesized with acridine as a donor and benzophenone as an acceptor. Solution-processed OLEDs were prepared based on M1 and P1 as doped light-emitting layer, and M1-based doped device could achieve maximum external quantum efficiency of up to 20.6% with blue-light emission.

Graphene (G) and its derivatives are important nanomaterials with potential medical applications for biosensors and implanting biomaterials. The hydrophobicity and surface microstructures of substrates have great influences on the biological and physical properties of the surface-bound cells. In this work, we used the two-beam laser interference (TBLI) technique to prepare a two-dimensional (2-D) grating structure on the surface of graphene oxide (GO) film. We investigated the effect of GO and the GO film with the 2-D grating structure substrates on the growth behavior of rat brain microvascular endothelial (bEnd.3) cells. The results demonstrated that the cell spreading area and the number of surface-bound cells were closely related to the hydrophobicity of the substrate and the presence of oxygen-containing functional groups (OCGs). Due to the interaction of laser and GO, the GO in the interference area was transformed into reduced graphene oxide (RGO). The grating-structured GO film significantly affected the direction of cell spreading and morphology. It has a good application prospect as a scaffold in tissue engineering, and promising applications in the fields that require highly directional growth of cells, such as nerve injury repair, tendon repair and regeneration.

Materials exhibiting thermally activated delayed fluorescence (TADF) have been extensively explored in the last decade. These emitters have great potential of being used in organic light-emitting diodes because they allow for high quantum efficiencies by utilizing triplet states via reverse intersystem crossing. In small molecules, this is done by spatially separating the highest occupied molecular orbital from the lowest unoccupied molecular orbital, forming an intramolecular charge-transfer (iCT) state and leading to a small energy difference between lowest excited singlet and triplet states (ΔEST). However, in polymer emitters, this is harder to achieve, and typical strategies usually include adding known TADF units as sidechains onto a polymer backbone. In a previous work, we proposed an alternative way to achieve a TADF polymer by repeating a non-TADF unit, polymerizing it via electron-donating carbazole moieties. The extended conjugation on the backbone reduced the ΔEST and allowed for an efficient TADF polymer. In this work, we present a more in-depth study of the shift from a non-TADF monomer to TADF oligomers. The monomer shows non-TADF emission, and we find the delayed emission to be of triplet-triplet annihilation origin. An iCT state is formed already in the dimer, leading to a much more efficient TADF emission. This is confirmed by an almost two-fold increase of photoluminescence quantum yield, a decrease in the delayed luminescence lifetime, and the respective spectral lineshapes of the molecules.

Molybdenum disulfide (MoS2) has received enormous attentions in the electrochemical energy storage due to its unique two-dimensional layered structure and relatively high reversible capacity. However, the application of MoS2 in potassium-ion batteries (PIBs) is restricted by poor rate capability and cyclability, which are associated with the sluggish reaction kinetics and the huge volume expansion during K+ intercalation. Herein, we propose a two-dimensional (2D) space confined strategy to construct van der Waals heterostructure for superior PIB anode, in which the MoS2 nanosheets can be well dispersed on reduced graphene oxide nanosheets by leveraging the confinement effect within the graphene layers and amorphous carbon. The strong synergistic effects in 2D van der Waals heterostructure can extremely promote the electron transportation and ions diffusion during K+ insertion/extraction. More significantly, the 2D space-confinement effect and van der Waals force inhibit polysulfide conversion product dissolution into the electrolyte, which significantly strengthens the structural durability during the long-term cycling process. As anticipated, the as-synthesized the “face-to-face” C/MoS2/G anode delivers remarkable K-storage performance, especially for high reversible capacity (362.5 mAh·g−1 at 0.1 A·g−1), excellent rate capability (195.4 mAh·g−1 at 10 Ag−1) and superior ultrahigh-rate long-cycling stability (126.4 mAh·g−1 after 4000 cycles at high rate of 5 A·g−1). This work presents a promise strategy of structure designing and composition optimization for 2D layered materials in advanced energy storage application.

Sugar metabolism is among the most important metabolic processes in soybean; it not only affects growth and development, but also plays a role in drought resistance. As a plant biological regulator, exogenous melatonin is assumed to regulate sugar metabolism. Here, physiological and transcriptomic approaches were used to determine the effects of melatonin on physiological indices and key genes and pathways associated with soybean sugar metabolism under drought stress. In plants subjected to drought stress, melatonin treatment increased dry matter accumulation, reduced malondialdehyde content, and increased the content of metabolized sugars in leaves, thereby enhancing soybean yield. Transcriptome analysis revealed that the genes differentially expressed in plants subjected to melatonin treatment and drought stress were enriched in the KEGG “sucrose and starch metabolism” pathway related to glucose metabolism. Among the differentially expressed genes, we identified 12 significantly altered genes associated with glucose metabolism that played roles in regulating the activities of glucose metabolism-related enzymes. Collectively, our results indicated that melatonin can enhance the output of glucose metabolites and tolerance of soybean subjected to drought stress by regulating the genes associated with glucose metabolism and activation of the related enzymes. Our findings provide a detailed theoretical basis for analyzing the regulatory effects of melatonin on soybean sugar metabolism under conditions of drought stress.

The complexity of a supply chain makes product safety or quality issues extremely difficult to track, especially for the basic agricultural food supply chains of people’s daily diets. The existing agricultural food supply chains present several major problems, such as numerous participants, inconvenient communication caused by long supply chain cycles, data distrust between participants and the centralized system. The emergence of blockchain technology effectively solves the pain-point problem existing in the traceability system of agricultural food supply chains. This paper proposes a framework based on the consortium and smart contracts to track and trace the workflow of agricultural food supply chains, implement traceability and shareability of supply chains, and break down the information islands between enterprises as much as possible to eliminate the need for the central institutions and agencies and improve the integrity of the transaction records, reliability and security. At the same time, farmers record details of the environment and crop growth data in the InterPlanetary File System (IPFS) and store file IPFS hashes in smart contracts, which not only increases data security but also alleviates the blockchain storage explosion problem. This framework has been applied in Shanwei Lvfengyuan Modern Agricultural Development Co., Ltd. Although there are still many defects, the framework has successfully realized functions such as disintermediation and tracing of agricultural product information through QR codes. Thus, the framework proposed in this paper is of great significance and reference value for enterprises to ensure product quality and safety traceability.

In this paper, a way to improve the temperature stability of DC conductivity and breakdown characteristics of polyethylene (PE) is proposed using a crosslinked linear low density polyethylene (LLDPE). The ratio of DC conductivity, as well as breakdown strength values under 90 to 30°C is used to determine the temperature stability of DC properties. The closer it is to 1, the better the performance of temperature stability. The results show that when using crosslinked-LLDPE material, the ratio of DC conductivity under 90 to 30°C is 10.5, while it is 461.6 for crosslinked-LDPE samples with the same DCP content. And the ratio of DC breakdown strength is 0.97 for crosslinked-LLDPE, while it is 0.32 for crosslinked-LDPE. The gel permeation chromatography (GPC) method, hot-set test, differential scanning calorimetry (DSC) analysis and scanning electron microscopy (SEM) images show that the fine arrangement and smaller molecular weight between crosslinks of molecular and morphology structure that LLDPE owns contribute to the improvement in comparison with LDPE. The findings may contribute a solution to the development of HVDC power cable insulation materials.

Background Although more information has become available on the occurrence of phthalates and di(2-ethylhexyl) adipate (DEHA) in foods including cow’s milk, information on their presence in human milk, the important and recommended sole diet for infants up to six months of age, is very limited, especially for DEHA. Objective To develop a GC-MS method for simultaneous analysis of DEHA and phthalates in human milk samples and generate occurrence data for exposure assessment. Method Human milk samples were extracted with acetonitrile followed by dispersive solid-phase extraction and GC-MS analysis. Results Among the 305 human milk samples collected from the Canadian Maternal-Infant Research on Environmental Chemicals Study, some phthalates (DHxP, BBzP, and DOP) were not detected in any of the samples, while DEHA and the other phthalates (DMP, DEP, DBP, DiBP, and DEHP) were detected at low frequencies with levels from 30.4–237 ng/g in up to 31 of the 305 human milk samples. Conclusions In general, DEHA and phthalates were detected at low frequencies and low levels in the 305 human milk samples. Highlights A GC-MS method based on dispersive solid phase extraction was developed for analysis of DEHA and eight phthalates in 305 human milk samples for exposure assessment.

In order to satisfy the requirement of precise pin-point landing mission in Mars exploration, this paper proposes an innovative visual navigation algorithm based on feature lines extraction and matching to estimate the attitude and position of the lander during descent phase. Currently, common navigation landmarks are feature points and craters. But, the number of feature points extracted from landing image is so large that the image process is complex and time-consuming, and they do not usually have absolute coordinate information to absolute navigation. Meanwhile, crater is matched difficultly. Hence, ridges, fissures and other surface textures similar to lines are most common visual features of Mars and can be used as navigation landmarks for visual absolute and relative navigation. Firstly, that feature lines matching based on the EDLine algorithm remains invariant to scaling, rotation, and illumination, etc. provides the basis for visual navigation by using feature line. Secondly, feature lines selected as navigation landmarks can be used to absolute navigation and relative navigation respectively, which can implement integrated navigation. In this paper, a novel integrated visual navigation has been designed to finish the precise pin-point landing and overcome the accumulated errors of relative navigation and the limited application range of absolute navigation. Experimental simulation results show that the integrated navigation algorithm solves the limitation of single navigation mode and improves the effectiveness and stability of the algorithm.

Structure control is widely admitted as a feasible strategy to restrain volume change and enhance electrical conductivity for chalcogenide anode materials. Herein, three-dimensionally hierarchical structure Co0.85Se@N-doped graphene hybrid is well-designed and synthesized by a facile hydrothermal strategy and post-calcination. It is noted that, owing to the nanoscale Kirkendall effect, the Co0.85Se nanograins derived from uniform zeolitic imidazolate framework (ZIF-67) precursor are incorporated into a polyhedron-in-polyhedron structure, which is consisted of in-situ formed amorphous carbon and interconnected pliable graphene nanosheets with enormous N-doping atoms. This unique dual-carbon protecting layers are beneficial to mitigate the volume expansion with high integrity, and facilitate the fast Li/electron transport with improved conductivity simultaneously, thus resulting in the superior Li-storage performance. As expected, the framework-controlled Co0.85Se@N-doped rGO composite demonstrates an outstanding cycling stability (787.7 mA h g−1 after 1000 cycles at 2 A g−1) and remarkable rate capability (400.8 mA h g−1 at ultrahigh rate of 10 A g−1). This work presents an enlightened strategy to design chalcogenide anode with desired nano-/microstructure by structure control and kinetic increase.

Kadsura heteroclita Roxb. Craib. (Schisandraceae), is a vine plant mainly distributed in southwest part of China. A new dibenzocyclooctadiene lignan, kadsulignan W (1), along with eleven known lignans (2-12) were isolated from chloroform soluble fraction of stems of Kadsura heteroclita. The structure of new lignan was elucidated by extensive spectroscopic techniques, namely one- and two-dimensional NMR spectroscopy, and HRESI-MS analysis. The absolute configuration of the biphenyl ring in the new dibenzocyclooctadiene lignan was discerned by circular dichroism (CD) spectroscopy. Antioxidative effects of these compounds were evaluated on human isolated neutrophils, and compounds 5, 8, 9, and 10 were found to be strongly active with the IC50 of 36.68, 34.41, 35.97, and 33.65 µM, respectively. Furthermore, compound 8 was also found to be cytotoxic against human gastric cancer cells (BGC 823), and human cervical cancer cell lines (HeLa) with the IC50 values of 11.0, and 23.8 µM, respectively.

Herein, we present a ruthenium-catalyzed new hydrogen evolution ortho-aminoalkylation of phenolic derivatives with cyclic amines as the coupling agents. The developed cross-coupling reaction offers a practical platform for direct access to a variety of functionalized phenols with the features of good substrate and functional group compatibility, readily available catalyst system and feedstocks, no need for additional sacrificial oxidants, and high atom efficiency.

An efficient strategy of surface engineering is developed to extraordinarily boost the energy density of multiscale porous carbon cloth for aqueous symmetric supercapacitors by optimizing the oxygen-containing functional groups. The operating voltage with neutral electrolyte is remarkably broadened from 1.3 to 1.8 V for electrochemical oxidized active carbon cloth (EOACC), enabling its ultrahigh areal capacitance (1548 mF cm−2) and extraordinary energy density (239.25 μWh cm−2). More importantly, engineering such a functionalized electrode with improved operating potential window is critically hinged on the fundamental understanding of the underlying electrochemical mechanism. The outstanding performance can be attributed to the enlarged ions-accessible specific surface area and created electrochemical active C O quinone-type groups, contributing to the combination of electrical double-layer capacitance and pseudo-capacitance, respectively. More significantly, the broadened potential window is originated from the increase of the onset overpotential for oxygen evolution reaction, induced by the physical barrier of adsorbed Na+ and the kinetic limitations of fast faradic redox reactions. This strategy sheds a light on the understanding of the electrochemical mechanism for broadened potential range, which provides a promising way for designing and engineering carbon-based aqueous supercapacitors with boosted energy density.

Objective To study the antipyretic and anti-inflammatory constituents from the active fraction of Reduning (RDN) Injection. Methods In this study, the active fraction of RDN Injection was screened by the LPS-induced mouse endotoxin shock model. The chemical constituents were isolated by chromatography on HP-20 macroporous adsorptive resins, silica gel, ODS columns and reverse phase MPLC and HPLC repeatedly, and their structures were elucidated based on spectroscopic analysis (HR-ESI-MS, NMR, ECD) and chemical methods. Meanwhile, we evaluated the anti-inflammatory activities of the isolates by measuring their inhibitory effects on TNF-α production in LPS stimulated RAW 264.7 macrophages. Results The 95% ethanol eluate of RDN Injection by the macroporous adsorption resin column was proved to be the antipyretic and anti-inflammatory active fraction of this injection. A novel iridoid, named jasminoide A (1), and a new guaiane sesquiterpenoid, named (1R,7R,8S,10R)-7,8,11-trihydroxy-4-guaien-3-one (2), were isolated from Reduning injection, and compound 2 can inhibit TNF-α production with IC50 values of 72.24 µmol/L. Conclusion In this study, two new terpenoids were isolated from Reduning Injection, and compound 2 showed inhibitory activity against LPS-activated TNF-α production in RAW 264.7 cells in vitro.

To date, although tremendous advances have been made in N-heteroaryl C–H functionalization, there remain significant unmet challenges in the deconstruction of extensively applied but poorly reactiv...

Constructing heterojunction and introducing interfacial interaction by designing ideal structures have the inherent advantages of optimizing electronic structure and macroscopic mechanical property...

Owing to their abundant resources and high theoretical capacities, nanostructured metal sulfides exhibit attractive potential to be used as anode materials for lithium-ion batteries. However, engin...

Conjugated polymers are of high potential in the development of spintronic devices. In this paper, we report systematic studies on spin transport properties of a semiconducting polymer PBDTTT-C-T in the permalloy/polymer/Pt trilayer using the spin pumping method. Pure spin current with long spin relaxation time is observed via the inverse spin Hall effect (ISHE) measurements. Furthermore, spin current is also found to propagate through the blend film consisting of a small amount of PBDTTT-C-T in an insulating matrix. The polymer blend exhibits a remarkably enhanced spin relaxation length (56 nm) and carrier mobility compared to pristine PBDTTT-C-T. From film microstructural characterizations, we propose that the enhanced spin/carrier transport properties are attributed to the formation of interlinked nanonetwork comprising of the PBDTTT-C-T chain bundles in the inert matrix to afford efficient intrachain charge conduction pathway. Temperature- dependent ISHE measurements support the spin-orbit coupling dominated spin relaxation mechanism.

In the field of visual navigation, crater is an ideal navigation landmark on planet surface, because of its universality and significance. During the descent phase of lander, crater needs to be extracted and matched. However, as the landing proceeds, images taken by the on-board camera will change, such as the variation of scale, translation, rotation, illumination which will increase the difficulty of the matching algorithm. This paper proposes a more accurate and faster crater matching algorithm based on feature descriptor. This algorithm is designed for navigation during the descending phase. It has the invariance of scaling, rotation, illumination. First, this algorithm extracts circular arc by Gaussian Pyramid and ELSD algorithm, so that this algorithm has the invariance against scale variation. Then, in order to describe the circular arc, this algorithm determine the direction of the circular arc by the direction histogram. And this algorithm constructs the circular arc band descriptors in the support region to achieve translation, rotation and illumination invariance. At last, matching criteria is the combination of the Nearest Neighbor Distance Ratio (NNDR) and the Euclidean distance constraint. The results are obtained under different image variations. The matching results show that this crater matching algorithm has high crater correct extracting and matching rate and high computationally efficient.

Improving the short-circuit current density (Jsc) is a big challenge for gaining highly efficient nonfullerene all-small-molecule organic solar cells (NFASM-OSCs). Herein, a novel small molecular donor, BT-2F which is derived from previously reported BTEC-2F, was designed and synthesized. The shortened alkyl-chains with higher regularity endow BT-2F with more ordered packing arrangement and more compact lamellar stacking as evidenced by the characterization of differential scanning calorimetry and grazing incidence X-ray diffraction. By blending BT-2F with Y6 or N3, BT-2F based devices showed impressive power conversion efficiencies (PCEs) of 13.80% and 14.09% respectively, much higher than the reported PCE of 13.34% for BTEC-2F:Y6. Besides, the efficiency of 14.09% is also among the highest PCE values reported so far for NFASM-OSCs. The distinctly improved Jsc resulted in enhanced PCE values, meanwhile both BT-2F:Y6 and BT-2F:N3 still maintain high fill factors of over 70%, which are ascribed to the good balance between high crystallinity and appropriate phase separation.

Research on alkylbenzene side-chain engineering of acceptors, which can affect the crystallinity of molecules and packing orientations of blend films, has deeply promoted the development of organic solar cells (OSCs). In this contribution, we developed two novel small-molecule electron acceptors C4 and C6. They exhibit similar optical (an absorption edge reaching 900 nm) and electrochemical properties (narrow band gap, Eg ≈ 1.55 eV), but their photovoltaic properties are quite different. The power conversion efficiency (PCE) of C6-based OSCs is 14.54% (VOC = 0.84 V, JSC = 23.82 mA cm−2, and FF = 72.68%), which is much higher than that of the C4-based control device (7.28%). The difference of PCE is because C6 shows excellent compatibility with the polymer donor PM6. The subtle change of the alkylbenzene side chain is found to have a great impact on the blend film morphology. Compared to PM6:C4 blend films, PM6:C6 blend films exhibit a smaller π–π stacking d-spacing (3.61 A) and larger coherence length (CCL = 17.7 A), which is beneficial to promote charge transfer, further affecting the PCE of OSCs. Notably, devices based on PM6:C6 can achieve 14.54% efficiency, which is one of the best efficiencies of annealing-free OSCs (AF-OSCs). In reality, AF-OSCs relatively simplify the device manufacturing process compared to annealed cells, manifesting remarkable application potential in the future.

The aim of this work is firstly to optimize T6 heat-treatment of low-pressure sand-cast Mg–10Gd–3Y–0.5Zr alloy, and then systematically investigate the mechanical behavior of the T6-treated alloy from room temperature to 300 °C. It turned out that the optimum T6 heat-treatments for the tested alloy are 525 °C × 12 h + 225 °C × 14 h and 525 °C × 12 h + 250 °C × 12 h which integrated age-hardening and tensile properties into account, respectively. The strength of the T6-treated alloy indicates obvious anomalous temperature dependence from room temperature to 300 °C, namely both ultimate tensile strength and yield strength of the tested alloy firstly increase with tensile temperature, and then decrease as temperature increases further. Elongation increased with temperature monotonously. The tensile fracture mode of the tested alloy changes from transgranular fracture to intergranular fracture with the increasing of test temperature. Keywords: Mg–Gd–Y–Zr, Heat treatment, High temperature tensile property, Anomalous temperature dependence

In gravity gradient inversion, to choose an appropriate component combination is very important, that needs to understand the function of each component of gravity gradient in the inversion. In this paper, based on the previous research on the characteristics of gravity gradient components, we propose a reweighted inversion method to evaluate the influence of single gravity gradient component on the inversion resolution The proposed method only adopts the misfit function of the regularized equation and introduce a depth weighting function to overcome skin effect produced in gravity gradient inversion. A comparison between different inversion results was undertaken to verify the influence of the depth weighting function on the inversion result resolution. To avoid the premise of introducing prior information, we select the depth weighting function based on the sensitivity matrix. The inversion results using the single-prism model and the complex model show that the influence of different components on the resolution of inversion results is different in different directions, however, the inversion results based on two kind of models with adding different levels of random noise are basically consistent with the results of inversion without noises. Finally, the method was applied to real data from the Vinton salt dome, Louisiana, USA.

Contamination of agricultural soil with cadmium (Cd) poses a severe threat to food safety and human health, especially for Cd in rice. It is very important to identify Cd bioaccumulation in rice in order to screen Cd-safe cultivars. In the present study, 183 pairs of rice and soil data collected from Cd-contaminated soil were used to investigate the differences of Cd bioaccumulation in grains among rice cultivars. The results showed that the adverse effect on grain Cd accumulation of japonica was less than that of indica under Cd exposure. The percentage of japonica with grain Cd concentration exceeding 0.2 mg/kg reduced 50.3% compared with indica. Partial correlation analyses suggested that lower pH contributed to Cd accumulation in grains, and a significant increase in grain Cd concentration was observed with increasing soil Cd concentration. The bioaccumulation factors (BCF) of Cd in rice grains could be divided into 5 grades by combining an empirical soil-plant transfer model with species sensitivity distribution (SSD). Grades with lower Cd bioaccumulation (grades 1 and 2) were dominated by japonica, and the intrinsic sensitivity index of Cd-enrichment (k value) and straw to grain transfer factors (TF) increased with ascending grades. Average k value and TF of cultivars in grade 5 were 1.4–7.9 and 1.5–5.7 times higher than those of cultivars in grades 1 to 4, which eventually caused the increase of Cd accumulation in grains. The lower level of Cd absorption and translocation contributed to reducing the bioaccumulation of Cd in rice grains had been proved by the classification of rice on Cd accumulation. Considering the influence of soil properties and intrinsic sensitivity of rice, cultivars with grain Cd bioaccumulation controlled at low levels to safe for human consumption could be identified on Cd-contaminated soils.

The stiffness and the topography of the substrate at the cell–substrate interface are two key properties influencing cell behavior. In this paper, atomic force acoustic microscopy (AFAM) is used to investigate the influence of substrate stiffness and substrate topography on the responses of L929 fibroblasts. This combined nondestructive technique is able to characterize materials at high lateral resolution. To produce substrates of tunable stiffness and topography, we imprint nanostripe patterns on undeveloped and developed SU-8 photoresist films using electron-beam lithography (EBL). Elastic deformations of the substrate surfaces and the cells are revealed by AFAM. Our results show that AFAM is capable of imaging surface elastic deformations. By immunofluorescence experiments, we find that the L929 cells significantly elongate on the patterned stiffness substrate, whereas the elasticity of the pattern has only little effect on the spreading of the L929 cells. The influence of the topography pattern on the cell alignment and morphology is even more pronounced leading to an arrangement of the cells along the nanostripe pattern. Our method is useful for the quantitative characterization of cell–substrate interactions and provides guidance for the tissue regeneration therapy in biomedicine.

Despite the widespread applications of 2-(hetero)aryl N-heteroarenes in numerous fields of science and technology, universal access to such compounds is hampered due to the lack of a general method for their synthesis. Herein, by a H2O-mediated H2-evolution cross-coupling strategy, we report an iridium(III)-catalyzed facile method to direct α-arylation of N-heteroarenes with both aryl and heteroaryl boronic acids, proceeding with broad substrate scope and excellent functional compatibility, oxidant and reductant-free conditions, operational simplicity, easy scalability, and no need for prefunctionalization of N-heteroarenes. This method is applicable for structural modification of biomedical molecules, and offers a practical route for direct access to 2-(hetero)aryl N-heteroarenes, a class of potential cyclometalated C^N ligands and N^N bidentate ligands that are difficult to prepare with the existing α-C-H arylation methods, thus filling an important gap in the capabilities of synthetic organic chemistry., 2-(hetero)aryl N-heteroarenes are ubiquitously applied in numerous fields of science and useful for the development of bioactive molecules and drugs, but there is a lack of general methods for their synthesis. Here, the authors report an iridium(III)-catalyzed method for direct α-arylation of N-heteroarenes with aryl and heteroaryl boronic acids, by a H2O-mediated H2-evolution cross-coupling strategy.

Background Spodoptera frugiperda is a serious pest that causes devastating losses to many major crops, including corn, rice, sugarcane, and peanut. Camptothecin (CPT) is a bioactive secondary metabolite of the woody plant Camptotheca acuminata, which has shown high toxicity to various pests. However, the effect of CPT against S. frugiperda remains unknown. Results In this study, bioassays have been conducted on the growth inhibition of CPT on S. frugiperda larvae. Histological and cytological changes were examined in the midgut of larvae fed on an artificial diet supplemented with 1.0 and 5.0 µg/g CPT. The potential molecular mechanism was explored by comparative transcriptomic analyses among midgut samples obtained from larvae under different treatments. A total of 915 and 3560 differentially expressed genes (DEGs) were identified from samples treated with 1.0 and 5.0 µg/g CPT, respectively. Among the identified genes were those encoding detoxification-related proteins and components of peritrophic membrane such as mucins and cuticle proteins. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses indicated that part of DEGs were involved in DNA replication, digestion, immunity, endocrine system, and metabolism. Conclusions Our results provide useful information on the molecular basis for the impact of CPT on S. frugiperda and for future studies on potential practical application.

Zr-Te compounds are an ideal platform to investigate novel electrical transport properties. Here we report the Kondo effect in single-crystalline ${\mathrm{ZrTe}}_{2}$. When $Tl8$ K, ${\mathrm{ZrTe}}_{2}$ exhibits a $\mathrm{log}T$ dependence of resistivity, which may derive from three different mechanisms, including electron-electron interaction, weak localization, and Kondo effect. By measuring transport properties with magnetic field along different directions, the former two mechanisms were excluded. Isotropic negative magnetoresistance was extracted by subtracting different quadratic background signals caused by Lorentz force, which reveals the existence of a weak Kondo effect in this material.

As an intensively studied electrode material for secondary batteries, TiS2 is known to exhibit high electrical conductivity without extrinsic doping. However, the origin of this high conductivity, either being a semimetal or a heavily self-doped semiconductor, has been debated for several decades. Here, combining quasi-particle GW calculations, density functional theory (DFT) study on intrinsic defects, and scanning tunneling microscopy/spectroscopy (STM/STS) measurements, we conclude that stoichiometric TiS2 is a semiconductor with an indirect band gap of about 0.5 eV. The high conductivity of TiS2 is therefore caused by heavy self-doping. Our DFT results suggest that the dominant donor defect that is responsible for the self-doping under thermal equilibrium is Ti interstitial, which is corroborated by our STM/STS measurements.

Due to their ultra-high theoretical capacity and low discharge potential, rich Sn-based materials are considered promising candidates for lithium ion battery (LIB) anodes; however, the development of SnOx electrodes is restricted by their low conductivity and severe volume change during repeated cycling. In this study, carbon matrix encapsulating heterostructured SnOx ultrafine nanoparticles (SnOx@C/rGO) were synthesized in situ through a facile solvent mixing, followed by thermal calcination. During the decomposition of the Sn-organic precursor, the sizes of the as-prepared SnOx nanoparticles were strictly controlled to 5–10 nm; they were intimately wrapped by the in-situ formation of ultrathin carbon layers, which prevented the agglomeration of nanograins. Furthermore, the SnOx@C nanoparticles were evenly anchored on the surface of reduced graphene oxide (rGO) to construct a highly conductive carbon framework. It is notable that the carbon matrix prepared in situ can accommodate the volumetric change of SnOx and facilitate the transport of Li+ ions during continuous cycling. Benefiting from the synergistic effect between the SnOx nanoparticles and carbon matrix prepared in situ, the heterostructured SnOx@C/rGO will confer improved structural stability and reaction kinetics for lithium storage. It delivers a stable reversible discharge capacity of 1092.2 mAh g−1 at a current rate of 0.1 A g−1, and enhanced cycling retention with a capacity of 447.8 mAh g−1 after 1200 cycles at a current rate of 5.0 A g−1. This strategy provides a rational avenue to design oxide anodes with efficient hierarchical structure for LIB development.

Alloying is an important strategy for the design of catalytic materials beyond pure metals. The conventional alloy catalysts however lack precise control over the local atomic structures of active ...

The laser-interference-induced backward transfer (LIIBT) that occurred during the nanostripe structuring of materials, performed by two-beam laser interference at the ITO glass/silicon wafer system under a normal atmospheric environment. The results showed that the nanostripe structures with nanoparticles (NPs) can be obtained at the laser fluence of 65–95 mJ·cm−2 for the laser duration of 100 and 200 pulses, respectively. The EDX analysis revealed that the silicon element was transferred on the surface of the nanostripe structures. In addition, Raman spectra with the peaks at ~520 cm−1 verified that the crystalline silicon was deposited on the nanostripe structures during the LIIBT process. Furthermore, the photoluminescence (PL) spectrum with the peak at ~395 nm belongs to the In2O3 nanostructure at the laser fluence of 45 mJ·cm−2 for 200 pulses. The peak at ~405 nm corresponds to the silicon nanostructures and it is covered by SiO at the laser fluence of 75 mJ·cm−2 for 200 pulses. The LIIBT shown here would greatly reduce the complexity in the fabrication of the nanostripe structures and give an impetus to the laser-induced backward transfer.

Characteristics of Chlorella sorokiniana treating wastewater with consideration of HRT (6 d, 16 h, 8 h), hydraulic conditions, light or dark culture were evaluated and compared with activated sludge. Results showed that optimal HRT was 8 h; if longer, effluent chemical oxygen demand (COD) and NH4+-N in the dark began to rebound. Mixing was beneficial to COD removal of algae, while aeration was suitable for nutrient removal. Growth of C. sorokiniana in the light was mixotrophic growth and 1.3–1.7 times more than that of dark heterotrophic growth. The maximum specific growth rate (µmax), productivity, and biomass yields on COD (YCOD), N (YNH4), P (YP) of algae were higher in the light than that in the dark. COD assimilation capacity of algae was similar to activated sludge but with different dynamics. N and P assimilation capacity of algae was 1.4, 1.2–2.5 times more than activated sludge; N and P removal efficiency of algae was 5%–10%, 10%–55% respectively higher than activated sludge. This study confirmed the advantage of algae over activated sludge and reveal why algae could assist the activated sludge process.

It is already known that bisphenol S (BPS) has been used as a substitute for BPA in thermal papers in recent years. It is not clear, however, if BPS has also been used to replace BPA in can coatings as currently being speculated due to a lack of credible studies on migration of BPS from can coatings and occurrence data of BPS in foods. In this study, an LC-MS/MS method was developed for the analysis of BPS, along with several other bisphenols, and method detection limits for BPS varied from 0.0017 to 3.1 ng/g depending on the type of sample matrix and the amount of sample analysed. This method was used to analyse 159 different food composite samples from a recent Canadian total diet study. Bisphenol E (BPE), bisphenol B (BPB), and bisphenol AF (BPAF) were not detected in any of the 159 food composite samples, bisphenol F (BPF) was detected in only three samples (25-2360 ng/g), and bisphenol A (BPA) was detected in 10 samples (5.3-41 ng/g) which were all prepared from canned foods. BPS was not detected in any of the canned food composite samples but was detected in nine food composite samples prepared from meat and meat products (1.2-35 ng/g), indicating sources for BPS other than can coatings may be possible, which will be investigated in future studies.

The failure modes of molecular junctions have been only sporadically investigated, but they are important to understand so they can be prevented and molecular junctions can be optimized. Although i...

This study investigated the trophic transfer of four common toxic metals (Cd, Cr, Cu and Hg) in the food web and assessed their potential ecological risks in Laizhou Bay, a spawning area for fishery populations in the Bohai Sea, North China. Based on the predation relations of 43 species that were representatives of the main trophic levels (TLs), a simplified food web was constructed using stomach content analysis and stable nitrogen isotope ratio (δ15N) analysis. Using copepods as the baseline species (TL = 2.00), the TLs of the organisms ranged from 1.96 (Polychaeta) to 4.47 (Japanese flounder) and showed the following ranking order: predatory pelagic or demersal fish > medium demersal fish > crustacean, cephalopod, small pelagic or demersal fish > zooplankton and Polychaeta. The metals showed different trophic transfer behaviors in the food web. Hg and Cr tended to be efficiently biomagnified between TLs, along the main food chains and in the food web. Cu biodiluted significantly with increasing TLs, while Cd showed no biomagnification or biodilution trends in the food web. At low or moderate levels of Cd and Hg, potential ecological risks were detected in the water and sediments at only a few sites, indicating their overall low ecological risks in the environment. The metals in the important fishery species (four top predatory fish, two cephalopods and eight crustaceans) were below the permissible limits, except for Cd in octopus and paddle crab, which reached or exceeded the most restrictive criteria. Based on the provisional tolerable weekly intake (PTWI) criteria, the safe weekly human consumption levels by humans of the predatory fish, cephalopods and crustaceans were species-specific (0.20–4.44 kg) and should be cautiously assessed.

Methylmercury (MeHg) is a widespread pollutant in aquatic ecosystems, but its toxicity to the early life stages of marine fish has not been adequately investigated. This study used acute toxicity tests on embryonic-larval stages of a marine flounder Paralichthys olivaceus to determine the LC50 values for embryos and larvae and evaluate the responses of several biological endpoints to subacute MeHg exposure. Under exposures (0–15 μg L−1) below LC50 values (

Significance Deploying coal-bioenergy gasification systems with carbon capture and storage (CBECCS) provides a promising opportunity for China to realize its carbon mitigation and air pollution abatement goals simultaneously. We conducted a comprehensive assessment of CBECCS technology for China, with a focus on plant and fuel configurations (e.g., biomass ratios) and economics, as well as CO2 and greenhouse gas emissions and cobenefits for air quality. We find significant opportunities for carbon mitigation with air quality cobenefits from deployment of CBECCS systems in regions that are both rich in crop residues and facing urgent needs to curb serious air pollution. The study thus provides critical information for policy makers seeking to exploit the carbon-negative energy opportunities of CBECCS technology., Realizing the goal of the Paris Agreement to limit global warming to 2 °C by the end of this century will most likely require deployment of carbon-negative technologies. It is particularly important that China, as the world’s top carbon emitter, avoids being locked into carbon-intensive, coal-fired power-generation technologies and undertakes a smooth transition from high- to negative-carbon electricity production. We focus here on deploying a combination of coal and biomass energy to produce electricity in China using an integrated gasification cycle system combined with carbon capture and storage (CBECCS). Such a system will also reduce air pollutant emissions, thus contributing to China’s near-term goal of improving air quality. We evaluate the bus-bar electricity-generation prices for CBECCS with mixing ratios of crop residues varying from 0 to 100%, as well as associated costs for carbon mitigation and cobenefits for air quality. We find that CBECCS systems employing a crop residue ratio of 35% could produce electricity with net-zero life-cycle emissions of greenhouse gases, with a levelized cost of electricity of no more than 9.2 US cents per kilowatt hour. A carbon price of approximately $52.0 per ton would make CBECCS cost-competitive with pulverized coal power plants. Therefore, our results provide critical insights for designing a CBECCS strategy in China to harness near-term air-quality cobenefits while laying the foundation for achieving negative carbon emissions in the long run.

SnS2 has been extensive studied as an anode material for sodium storage owing to its high theoretical specific capacity, whereas the unsatisfied initial Coulombic efficiency (ICE) caused by the partial irreversible conversion reaction during the charge/discharge process is one of the critical issues that hamper its practical applications. Hence, heterostructured SnS2/Mn2SnS4/carbon nanoboxes (SMS/C NBs) have been developed by a facial wet-chemical method and utilized as the anode material of sodium ion batteries. SMS/C NBs can deliver an initial capacity of 841.2 mAh g–1 with high ICE of 90.8%, excellent rate capability (752.3, 604.7, 570.1, 546.9, 519.7, and 488.7 mAh g–1 at the current rate of 0.1, 0.5, 1.0, 2.0, 5.0, and 10.0 A g–1, respectively), and long cycling stability (522.5 mAh g–1 at 5.0 A g–1 after 500 cycles). The existence of SnS2/Mn2SnS4 heterojunctions can effectively stabilize the reaction products Sn and Na2S, greatly prevent the coarsening of nanosized Sn0, and enhance reversible conver...

The severe anticancer situation as well as the emergence of multidrug-resistant (MDR) cancer cells has created an urgent need for the development of novel anticancer drugs with different mechanisms of action. A large number of natural alkaloids, such as paclitaxel, vinblastine and camptothecin have already been successfully developed into chemotherapy agents. Following the success of these natural products, in this review, twenty-six types of isoquinoline alkaloids (a total of 379 alkaloids), including benzyltetrahydroisoquinoline, aporphine, oxoaporphine, isooxoaporphine, dimeric aporphine, bisbenzylisoquinoline, tetrahydroprotoberberine, protoberberine, protopine, dihydrobenzophenanthridine, benzophenanthridine, benzophenanthridine dimer, ipecac, simple isoquinoline, pavine, montanine, erythrina, chelidonine, tropoloisoquinoline, azafluoranthene, phthalideisoquinoline, naphthylisoquinoline, lycorine, crinane, narciclasine, and phenanthridone, were summarized based on their cytotoxic and MDR reversing activities against various cancer cells. Additionally, the structure-activity relationships of different types of isoquinoline alkaloid were also discussed. Interestingly, some aporphine, oxoaporphine, isooxoaporphine, bisbenzylisoquinoline, and protoberberine alkaloids display more potent anticancer activities or anti-MDR effects than positive control against the tested cancer cells and are regarded as attractive targets for discovery new anticancer drugs or lead compounds.

Three novel bisbenzimidazole derivatives have been synthesized and developed as dual-functional fluorescent sensors for the rapid and highly selective detection of Ag+ and Fe3+ ions in semi-aqueous medium with distinct spectral response for the first time. The absorption intensity is drastically decreased after the addition of Ag+. Contrarily, it is markedly increased upon the addition of Fe3+. And there is a good linear relation at low concentration of both Ag+ and Fe3+, which provides a quantitative method for their detection. Similarly, the sensors show a distinct fluorescence response towards Ag+ and Fe3+ with a different fluorescence color change under UV light. In addition, no significant changes and interference can be observed with other metal ions. The sensing mechanism studies confirm that the N atom in CN of benzimidazole ring of sensor 4a may bind with Ag+ or Fe3+ ion to form metal complex. And there is only a static quenching process for the 4-Ag+ complex system, but both dynamic and static quenching processes occur in the 4-Fe3+ complex system. Moreover, sensors 4 can steadily work in solution with a wide range of pH 4-13 and rapidly respond to Ag+ and Fe3+ with a response time of 10 s. Finally, the sensors have been successfully applied to the visual detection of Ag+ and Fe3+ not only in solution, but also in test paper.

Herein, the MoP@C nanocomposite was successfully fabricated via a facile sol–gel approach followed by an annealing process, which demonstrated excellent electrochemical properties as a novel anode for sodium storage. The addition of the surfactant Tween 80 led to the formation of strong P–C bonds, ensuring in situ formation of a thin carbon layer on the nanosized MoP particles, which could mitigate particle aggregation and maintain the stable framework. Moreover, owing to the synergistic effect between the MoP nanoparticles and the highly conductive carbon network, the MoP@C nanocomposite delivered high reversible capacity and a superior cyclability (maintaining 180.3 mA h g−1 after 250 cycles at 500 mA g−1). In addition, the sodium-storage mechanism of MoP was unraveled by the combined analyses of in situ X-ray diffraction and ex situ transmission electron microscopy, confirming an incomplete conversion reaction during the sodiation/desodiation process; this provided an insight into the structural evolution and Na+-ion storage performance of phosphide anodes.

Taking advantage of synergistic effects, the ternary metal oxides have attracted tremendous interest. Herein, ZnMn2O4 nano-particles have been fabricated via a facile one-step approach at room temperature, that of simply mixing ZnO and MnO in KOH aqueous solution without templates. When used as an anode for lithium ion batteries, it delivers the excellent structure stability (1028.9 mA h g−1 at 1.0 A g−1 after 400 cycles). Surprisingly, the low-cost and eco-friendly route provides a novel strategy to synthesize the mixed transition metal oxide electrodes with readily scaled-up production.

Controlling superconducting phase transition on a two-dimensional (2D) material is of great fundamental and technological interest from the viewpoint of making 2D resistance-free electronic circuits. Here, we demonstrate that a 1 T-to-2 H phase transition can be induced on the topmost monolayer of bulk (

Interstitial iron ( Fe i ) has strong influence on physical properties of Fe 1 + x Sb (0.08 ⩽ x ⩽ 0.38) compounds. We synthesized Fe 1.08 Sb single crystals with Fe i content close to the lower limit of solution area and investigated its transport and magnetic properties. The ac susceptibility and field dependence of magnetization measurements demonstrate that the transition at ∼9 K is a spin glass transition. By analyzing temperature dependence of susceptibility ( χ vs T) and resistivity (d2 ρ /dT2 vs T) results, we found a change of scattering in transport properties caused by the ordering of Fe i moments in this compound. In addition, the Hall resistivity results reveal that the hole-type carrier is dominant and the topological Hall effect induced by spin chirality is negligible in Fe 1.08 Sb.

Jin-hong tablets (JHT), a well-known Traditional Chinese Patent Medicine (TCPM), has been effectively used for the treatment of chronic superficial gastritis (CSG) in clinic. The metabolic profile of TCPMs is the key part of discovering their bioactive components. In this study, a five-step strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q/TOF-MS) and metabolynxTM software combined with mass defect filter (MDF) technique was developed to delineate the metabolic profile of JHT in vivo. As a result, a total of 163 JHT-related xenobiotics (38 prototypes and 125 metabolites) were identified or tentatively characterized in rat biological samples, and the phase I and II metabolism process mainly included demethylation, hydroxylation, sulfation and glucuronidation. In addition, after oral administration of JHT, a large amount of alkaloids-related ingredients were detected in rat plasma samples, indicating that alkaloids may play an important role in the treatment of CSG with JHT. This study is beneficial for understanding of JHT's in vivo metabolic profiles and characteristics, which helps to reveal its in vivo effective components and provides a solid basis for further studies on its functional mechanism.

Kinetic Monte Carlo models parameterized by first principles calculations are widely used to simulate atomic diffusion. However, accurately predicting the activation energies for diffusion in substitutional alloys remains challenging due to the wide variety of local environments that may exist around the diffusing atom. We address this challenge using a cluster expansion model that explicitly includes a sublattice of sites representing transition states and assess its accuracy in comparison with other models, such as the broken bond model and a model related to Marcus theory, by modeling vacancy-mediated diffusion in Pt-Ni nanoparticles. We find that the prediction error of the cluster expansion is similar to that of other models for small training sets, but with larger training sets the cluster expansion has a significantly lower prediction error than the other models with comparable execution speed. Of the simpler models, the model related to Marcus theory yields predictions of nanoparticle evolution that are most similar to those of the cluster expansion, and a weighted average of the two approaches has the lowest prediction error for activation energies across all training set sizes.