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The electrochemical reduction of CO2 (CO2RR) can substantially contribute to the production of useful chemicals and reduction of global CO2 emissions. Herein, we presented N and S dual-doped high-surface-area carbon materials (SZ-HCN) as CO2RR catalysts. N and S were doped by one-step pyrolysis of a N-containing polymer and S powder. ZnCl2 was applied as a volatile porogen to prepare porous SZ-HCN. SZ-HCN with a high specific surface area (1510 m2 g−g1) exhibited efficient electrocatalytic activity and selectivity for CO2RR. Electrochemical measurements demonstrated that SZ-HCN showed excellent catalytic performance for CO2-to-CO reduction with a high CO Faradaic efficiency (~93%) at −0.6 V. Furthermore, SZ-HCN offered a stable current density and high CO selectivity over at least 20 h continuous operation, revealing remarkable electrocatalytic durability. The experimental results and density functional theory calculations indicated that N and S dual-doped carbon materials required lower Gibbs free energy to form the COOH* intermediate than that for single-N-doped carbon for CO2-to-CO reduction, thereby enhancing CO2RR activity.

The tuning of physicochemical properties like particle sizes, surface modifications, etc., is essential to improve delivery efficiency with insignificant toxicity. A quantitative and mechanistic investigation on cellular uptake and intracellular trafficking of fluorescent-labeled polystyrene particles [50 and 500 nm plain and 200 nm and 1 µm carboxylate-coated polystyrene (PPS and CPS)] against breast cancer cells was performed. Examinations of cell proliferation, viability, and cytotoxicity indicated that those applied polymeric particles at concentrations of 4–40 µg/mL are non-toxic to cells except 200 nm CPS (16 µg/mL) which partially reduced cell viability. Quantitative fluorescent microscopy revealed that 200 nm CPS displayed the highest capability to be internalized by MCF-7 cells, in which the average intracellular particles are about 14 and 35 folds higher than 1 µm CPS and 500 nm PPS, respectively. Analysis of the uptake routes using inhibitors provided clear evidence that 200 CPS was mainly ingested via the clathrin-mediated endocytosis, whereas larger particles (> 500 nm) preferentially utilized the macropinocytosis pathway. Fluorescent live-cell imaging suggested that particles were mainly internalized by cells in an individual form instead of large aggregates, despite late occurrence of partial agglomeration in the cytoplasm. Overall, those outcomes enhanced our understanding of the application of polymeric delivery vehicles for the treatment of breast cancer.

Pitch length and surface braiding angle are two important parameters of braided composite preforms. In this paper, a method based on Faster R-CNN is proposed to measure the two parameters. First, after image acquisition, a fabric image database including initial cropped images, augmented images, and target images is established. Then, the target images are classified into four categories according to the gray change characteristics. Third, a Faster R-CNN fabric detection model is trained on the fabric image database. Fourth, targets are detected by the trained network, and corners are detected based on the detected targets. Finally, pitch lengths and surface braiding angles are measured based on the detected corners. Experimental results show that the proposed method achieves the automatic measurement of pitch lengths and surface braiding angles of 2D and 3D braided composite preforms with high accuracy.

Biochar and engineered biochar have been used for phosphorous recovery from wastewater, but the resulted phosphorous-laden (P-laden) biochar needs further disposal. In this study, the feasibility of reusing P-laden biochar for Pb immobilization as well as the underlying mechanism was explored. Three types of engineered biochar, i.e., Ca modified biochar, Mg modified biochar, and Fe modified biochar, were selected to sorb P and then the exhausted biochar was further used for Pb sorption. Results showed that Mg and Ca modified biochar exhibited considerable Pb sorption capacity after P sorption with the maximum value of 3.36–4.03 mmol/g and 5.49–6.58 mmol/g, respectively, while P-laden Fe modified biochar failed to sorb Pb due to its acidic pH. The removal of Pb by P-laden Mg modified biochar involved more precipitation including PbHPO4, Pb5(PO4)3(OH), and Pb3(CO3)2(OH)2 because of its higher P sorption capacity and more -OH group on the surface. Cation exchange with CaCO3 to form PbCO3 was the main mechanism for Pb removal by P-laden Ca modified biochar despite the formation of Pb5(PO4)3(OH) precipitate. Our results demonstrate that waste P-laden biochar can be further used for the effective removal of Pb, which provides a potential approach for waste adsorbent disposal.

Aiming at the concavity defects in the cross-wedge rolling (CWR) process, one new rolling method named as the twice closed–open joint CWR was presented to improve the use ratio of material in CWR of the axle parts. The new rolling method included three stages: the first closed rolling, the second closed rolling and the last open rolling. To investigate the flow of material in this rolling process, one 3D finite element model (FEM) of the twice closed–open joint CWR was established. The CWR process of one pump spindle part was simulated using the established 3D FEM. The formation, the flow law of metal materials and concavity defects of end were studied. In addition, the CWR experiments were carried out. The results of simulation agreed with the results of tests well. The results proved that the new method can decrease the extent of concavity and improve the material use ratio.

This work reports an experiment/simulation combination study on the magnetorheological (MR) mechanism of magnetic fluid based on Fe3O4 hollow chains. The decrease of shear stress versus the increasing magnetic field was observed in a dilute magnetic fluid. Hollow chains exhibited a higher MR effect than pure Fe3O4 hollow nanospheres under a small magnetic field. A modified particle level simulation method including the translational and rotational motion of chains was developed to comprehend the correlation between rheological properties and microstructures. Sloping cluster-like microstructures were formed under a weak external field (24 mT), while vertical column-like microstructures were observed under a strong field (240 mT). The decrease of shear stress was due to the strong reconstruction process of microstructures and the agglomeration of chains near the boundaries. The chain morphology increased the dip angle of microstructures and thus improved the MR effect under a weak field. This advantage made Fe3O4 hollow chains to be widely applied for small and low-power devices in the biomedical field. Dimensionless viscosity as a function of the Mason number was collapsed onto linear master curves. Magnetic fluid in Poiseuille flow in a microfluidic channel was also observed and simulated. A qualitative and quantitative correspondence between simulations and experiments was obtained.

Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air pollution during pregnancy on fetal growth have been investigated using ultrasound in many previous studies, the results were inconsistent and disputable. We aimed to qualitatively and quantitatively investigate the associations of air pollution exposure during different periods of pregnancy with fetal growth and anthropometric measurements at birth. We searched for all studies investigating the associations of air pollution exposure during pregnancy with fetal growth and birth anthropometric measurements in English and Chinese databases published before July 31, 2017. A random-effects model was employed in the meta-analysis to estimate the pooled effects of each 10 μg/m3 increment in air pollutant exposure. The ACROBAT-NRSI tool was applied to assess the quality of each included study, and the GRADE tool was employed to assess the overall quality of the meta-analysis. Maternal PM2.5 exposure (10 μg/m3) during the entire pregnancy was negatively associated with head circumference at birth (β = − 0.30 cm, 95% CI − 0.49, − 0.10), and NO2 exposure during the entire pregnancy was significantly linked to shorter length at birth (β = − 0.03 cm, 95% CI − 0.05, − 0.02). Maternal exposure to higher NO2 and PM2.5 during pregnancy may impair neonatal head circumference and length development, respectively. More studies are needed to confirm the effects of NO2 and PM2.5 and to identify the sources and major toxic components of PMs.

Indosinian granitic rocks are widespread in the West Qinling Orogen (WQO) in central China. Some of the early Indosinian granitoids have high Sr and low Y contents, and therefore high Sr/Y ratios, and they have been interpreted as adakitic rocks that formed by partial melting of thickened continental lower crust. However, several studies have revealed that granitoids with high Sr/Y ratios can be formed by various geological processes. Here, we report new zircon U-Pb ages, whole–rock geochemical data, and Sr–Nd–Hf isotope data for the Ganjiagongma pluton in the Xiahe area of the WQO, and we discuss whether the WQO underwent crustal thickening during the early Indosinian. The zircon U-Pb dating results indicate that the Ganjiagongma granodiorite and its mafic microgranular enclaves (MMEs) crystallized at ca 242 Ma. The MMEs are characterized by low SiO2 contents and Sr/Y ratios, and high MgO, Cr, and Ni contents, as well as high Mg# values, and they have evolved zircon Hf and whole–rock Sr-Nd isotopes, indicating they were produced by the partial melting of metasomatized continental lithospheric mantle. The granodiorite samples have some adakitic characteristics with SiO2 = 65.22 to 68.01 wt%, MgO = 1.07 to 1.71 wt%, Mg# = 59 to 62, Sr = 357 to 620 ppm, Y = 9.7 to 17.4 ppm, Sr/Y = 30.26 to 47.46, and no significant Eu anomalies. However, the granodiorites have relatively flat HREE patterns, indicating that amphibole, rather than garnet was the main residue in the source area, and this proposal is consistent with the relatively low but constant Nb/Ta values and varied Zr/Sm ratios. Simple two-end member modeling results indicate that the granodiorite could have been formed in normal or slightly thickened crust by mixing of 20%–30% mantle-derived melt with 70%–80% melt derived from the partial melting of basement rocks in the continental lower crust of the WQO. Taking into account other geological evidence, we propose that the formation of the Ganjiagongma pluton was related to the subduction of the A'nimaque-Mianlue oceanic crust, and that no significant thickening of the continental crust occurred in the WQO during the early Indosinian.

Magnetic fluid is a novel magnetorheological (MR) intelligent material consisting of magnetic particles, non-magnetic matrix, and additive agents. After applying the external magnetic field, magnetic particles will interact with each other due to the magnetic dipolar forces. The viscosity and yield stress of magnetic fluid could increase several orders of magnitude in milliseconds, which is called the MR effect. The controllable and reversible property makes magnetic fluid widely applied in drug targeting delivery, magnetic thermal therapy, commercial dampers, and polishing etc. In order to comprehend the mechanical behaviors of magnetic fluid, researchers developed several theoretical models for different flow conditions. However, due to the extensive calculation, theoretical models are only applicable for some special problems, such as 2-dimensional and axial symmetry. In recent years, with the development of computer performance, simulation has become an important method to investigate the MR mechanism of magnetic fluid. This paper reviews the recent progress in the theory and simulation of magnetic fluid. Firstly, theoretical models of magnetic fluid under shear mode, squeeze mode, and valve mode are introduced. Secondly, the existing simulation methods for magnetic fluid, such as molecular dynamics, particle-level dynamic simulation, and finite element method, are illustrated. The validity of the methods and their merits and drawbacks are discussed. Then, the research progress of the simulation of magnetic fluid is summarized from 3 aspects: Simulations of mechanical properties of novel magnetic fluid, simulations of complex mechanical behaviors of conventional magnetic fluid, and simulations of biomagnetic fluid. Finally, some future trends of simulation of magnetic fluid are proposed. The following 3 topics should be emphasized in the future work. First, a comprehensive theoretical model considering a variety of microscopic interactions is required. In order to prepare magnetic particles with high MR effect, excellent dispersibility, and low density, surface coating, modification, and additive agents are usually applied in experiments. Unfortunately, the influence of non-magnetic components on the MR effect is seldom considered in simulations. Second, current simulations could not simultaneously obtain the macroscopic mechanical properties and microstructures of magnetic fluid in complex flow. Finite element method and computational fluid dynamics are applicable for complex macroscopic problems but can not obtain the microstructures at the same time. Mesoscopic simulation methods can not exhibit large-scale aggregations of particles, which leads to the deviation compared with experiments. To establish multi-scale simulation methods and improve the accuracy of simulations have become an urgent requirement. Combining simulation methods with different spatial scales and reducing the time cost by using machine learning have become a possible approach. Third, multi-physics coupling simulation methods should be established. The magnetic field controlled electrical properties of magnetic fluid have attracted researchers interest in recent years. Magnetic fluid with this novel controllable property could be widely applied in battery and sensors. Investigations on other physical properties of magnetic fluid by using mechanical, electrical, and magnetic model together will be a future trend. These achievements will all contribute to the development of high-performance magnetic fluids and further enlarge the range of applications of magnetic fluid.

Early Palaeozoic ophiolites emplaced in the central East Kunlun fault zone (CEKF) offer critical clues to the tectonic evolution of the Proto-Tethys ocean and the accretionary process of CEKF. The Qushi'ang Ophiolite, located within the eastern segment of the CEKF, consists of dismembered serpentinites, meta-gabbros and meta-basalts. This study presents petrologic, whole-rock geochemical, and in situ zircon U-Pb and Hf isotope data for basic rocks (both metagabbros and metabasalts) from the Qushi'ang ophiolite to constrain the formation age and tectonic setting of the ophiolite. Zircons from two meta-gabbro samples yield concordant U-Pb ages of ca. 498 Ma and ca. 505 Ma, indicating that the Qushi'ang ophiolite was formed in the late Cambrian. The meta-gabbros and meta-basalts show significant enrichment in large ionic lithophile elements (LILEs), such as Cs, Rb, Ba, U, and Pb, and depletion in high field strength elements (HFSEs), such as Nb, Ta, Zr, and Ti, suggesting the influence of fluids derived from a subducting oceanic slab. On the N-MORB normalized trace element diagrams, these rocks share similar features with arc basalts and back-arc basalts and far away from fore-arc basalts (FABs) and normal mid-ocean basalts (N-MORBs). Low zircon eHf(t) values (−2.9 to +0.2) for the meta-gabbros further indicate that the Qushi'ang ophiolite likely originated from an weakly enriched mantle wedge source. Geochemical discrimination diagrams show that the Qushi'ang ophiolite formed in a back arc basin setting. Our new analyses, combined with previous data, suggest that the Qushi'ang ophiolite represents a relict of a nascent back-arc basin, similar to the scenario of the Okinawa trough in Western Pacific.

A series of 2D transition metal dichalcogenide (TMD) intercalation compounds, PdCl2/PtCl2@MX2 (M = Mo, W; X = S, Se), formed by covalently intercalating PdCl2/PtCl2 into the bilayer space of MX2, have been designed and investigated using density functional theory (DFT) and non-equilibrium Green's function (NEGF) methods. The intercalation compounds adopt a planar quadridentate coordination structure of PdCl2X2/PtCl2X2. The possibility of electron–hole recombination is enhanced because of the introduction of the PdCl2/PtCl2 groups, and on the other hand, the PdCl2/PtCl2-derived HOMO and LUMO are shielded well by the MX2 band gap, both of which are beneficial for improving the fluorescence quantum yield. The conductivity of the intercalation compounds is slightly lowered owing to the trap effect of PdCl2/PtCl2. In addition, electron transportation is easier along the zigzag direction than along the armchair direction. Contrary to the conductivity, a robust photogalvanic effect (PGE) can be observed when linearly polarized light is applied onto the PdCl2/PtCl2 groups, and the armchair direction exhibits a much higher photoresponse compared with the zigzag direction. The largest photocurrent could reach up to 1.83 × 10−2 a02 per photon. For a given MX2, the PdCl2 groups induce a higher maximum photocurrent than the PtCl2. Significantly, the photocurrent is highly dependent on the polarization angle θ and the applied photon energy, making the intercalation compounds appealing for designing photoresponse on/off switches by tuning θ or photon energy. Our simulation frameworks as well as the results offer guidelines for novel 2D functional device design and fabrication.

In this study, the normal stress in magnetorheological polymer gel (MRPG) under large amplitude oscillatory shear was investigated using experiments and particle-level simulations. Under large amplitude oscillatory shear, an intensely oscillating normal stress was measured with a period of exactly half the strain period. As the amplitude of the strain increased, the peak of the normal stress increased and the trough decreased. Changes in the normal stress were mainly caused by two factors: the Poynting effect, in which shear produces a normal force perpendicular to the shear direction, and magnetic-induced normal stress, which changes with the particle structure. In MRPG, both effects are related to the particle structure. The particle structure in MRPG with different strain was calculated and the simulation results show that the amplitude of the structural strain in oscillatory shearing is less than that of the applied strain. Additionally, a phase difference was observed between the structural strain and the applied strain. Based on the calculated particle structure, the change in the normal stress was obtained and found to agree well with the experimental results.

Voluminous granitoids located in the East Kunlun orogen (EKO) play an important role in characterizing the crustal growth and northward subduction of the Paleo-Tethys oceanic lithosphere. This paper presents new petrological, whole-rock geochemical, zircon U-Pb isotope geochronological and Sr-Nd-Hf isotopic data for the Halagatu granitoids (HG) pluton. The HG pluton comprises several different textural and compositional types, i.e., medium- to fine-grained granodiorites (MG), porphyritic monzogranites (PMG), coarse-grained monzogranites (CMG), and dark mafic microgranular enclaves (ME). U-Pb dating of zircons from the HG pluton yielded a weighted mean 206Pb/238U age of 248–244 Ma, which represents the crystallization age of the HG pluton. The whole-rock geochemical data indicate that the PMG, CMG and MG have similar geochemical features; for example, they are classified as high-K calc-alkaline, metaluminous to wildly peraluminous I-type granitoids, with negative Nb-Ta and Ti anomalies, low Mg# and Al2O3/(FeOT + MgO + TiO2) values, and high Th/Y ratios. These characteristics suggest the parent magmas were crustally derived. In contrast, the ME are characterized by medium-K calc-alkaline and metaluminous compositions, low Th/Y ratios and relatively high Mg#, Cr, and Ni values, likely suggesting these magmas were derived from a mantle source. Furthermore, the host granodiorites and microgranular enclaves have consistent Sr-Nd-Hf isotopic features, with eNd(t) values of −6.10 to −4.30 and zircon eHf(t) values of −7.8 to −0.4, indicating an enriched subcontinental lithospheric mantle (SCLM). On the basis of these values and the whole-rock geochemistry, the HG pluton magmas were the result of mixing between lithospheric mantle-derived and crust-derived magmas and that fractional crystallization (FC) played an important role in the formation of the HG pluton. The combination of these new data with previously published data reveals that the HG pluton was emplaced in a continental magmatic arc setting by the northward subduction of a branch of the Paleo-Tethys Ocean (Buqingshan Ocean) beneath the East Kunlun-Qaidam terrane (EKT) and that the Buqingshan Ocean began to subduct strongly northward in the late Permian (ca. 260 Ma), with subduction terminating during the late Middle Triassic (ca. 240 Ma).

The Central Kunlun ophiolitic melange zone, northern Tibetan Plateau, represents a remnant of the Early Paleozoic oceanic lithosphere. The Middle Ordovician Longshigeng basalts (LBs) are located in south of this melange zone and have important significance for reconstructing the opening and subduction processes of the Proto-Tethys Ocean. This study presents petrological, whole-rock geochemical, and zircon U-Pb data for these basalts. LA-ICP-MS U-Pb zircon data indicate that these basalts formed ca. 463 Ma. Geochemically, the basalts are characterized by low SiO2 (47.00–50.63 wt%) and K2O (0.22–1.05 wt%), intermediate Mg# (47–57) and high TiO2 (1.51–2.72 wt%), and are identified as tholeiitic basalts. Their chondrite-normalized REE patterns feature slight enrichments in LREEs (LREE/HREE = 2.11–3.08) with mild Eu anomalies (δEu = 0.89–1.06), and their patterns are similar to the reference line of enriched mid-ocean ridge basalt (EMORB). The primitive mantle-normalized trace element diagrams also show similarities with EMORB and are characterized by overall enrichments in large ion lithophile and high field strength elements, without notable Nb, Ta, and Ti depletions. Combining these data with the tectonic discrimination diagrams, we infer that these rocks formed in a back-arc environment in response to the northward subduction of the Proto-Tethys Ocean (South Kunlun Ocean) in the East Kunlun region, northern Tibetan Plateau.

The Fuyang River system (FRS) in north China, for a long time, is seriously polluted with organic compounds and heavy metals due to industrialization. However, the information on heavy metal pollution in this area is still limited, and health risks raised by trace elements are neglected up to now. To characterize the heavy metal pollutants and assess their potential ecological risks scientifically in FRS, surface sediments were collected from 66 sampling sites selected according to the hydrological and anthropogenic conditions along the river. A total of twelve metal pollutants (e.g., Cr, As, and Hg) in the sediments were detected among the distributaries. A combining application of geoaccumulation index (Igeo), ratio of secondary phase and primary phase (RSP), and the ecological risk factor (Eri) in this study gave systematic assessment results of single or combined pollution status raised by heavy metals in this area. The results show that Cr, Ni, Cu, As, Cd, Co, and Sn are mainly dispersed in the river reaches of Xingtai City and pose potential health risks in midstream, as per the geoaccumulation index and Pearson's correlation analyses. In particular, Cd accumulates strongly in sediments of Ming River and Aixinzhuang dam from Xingtai City. In upstream and downstream of FRS, the potential ecological risk is low, except in Yongnian County where high ecological risk was caused by Cd and Hg. These findings provide new insights into the pollution characteristics and assessment of the potential ecological risks induced by heavy metals along FRS, which suggest new directions should strategically tend to typical pollutants control by policy formulation and taking effective measures to prevent and manage heavy metal pollution in North China.

Phosphorus (P) is a valuable resource, while it is vastly lost with wastewater causing eutrophication. In this study, to recover P, composite biochars were prepared by pyrolyzing biowaste impregnated with FeCl3 or MgCl2. It was found that inherent mineral profiles in the biowastes played important roles in interacting with metal chlorides and determined P sorption and precipitation. Specifically, two biowastes containing distinct mineral contents, sawdust and sediment, were selected as model components, being alone or mixed at 1:1 (w/w) to prepare biochars with low, moderate and high mineral contents. Results showed that biochar itself could not absorb P, while loading FeCl3 or MgCl2 achieved P recovery rates of approximate 60–100% and 50–100%, respectively, via electrostatic attraction or ligand exchange of PO43− with –OH/-COOH, which was attributed to the enhanced positive charges and –OH/-COOH on the materials by these metal chlorides. Inherent minerals inhibited FeCl3 transforming into Fe3O4 in pyrolysis and promoted generation of Fe4(PO4)3(OH)3 in P sorption, thus high-mineral content was more appropriate for FeCl3 loading; however, precursors with low-mineral content was suitable for MgCl2 loading, since the bulk-C in biochar acted as porous structure to support MgO crystals with high superficial area (∼255.85 m2 g−1). Besides, FeCl3 and MgCl2 both drove dissolution of inherent minerals significantly, while inherent minerals inhibited release of soluble Fe and Mg2+ into solution, which minimized secondary pollution. This study implied that in constructing composite biochar for catching P, the type of metal chloride should match the inherent minerals in biowastes to maximize P recovery and minimize secondary pollution.

Welding fumes vary in composition depending on the materials and processes used, and while health outcomes in full-time welders have been widely studied, limited research on apprentices exists. Besides, few data are available for metals such as vanadium and antimony. This study aimed to look at individual metals present in welding fumes in the learning environment of apprentice welders. Forty-three welders and 41 controls were chosen from trade programmes at the Northern Alberta Institute of Technology. Ambient and personal air samples were collected at days 0, 1, 7, and 50 of their training and analysed for mass and metal concentrations using Inductively Coupled Plasma Mass Spectrometry. Results showed increases in particle and metal concentrations as apprentices progressed throughout their education and that concentrations at day 50 were similar to levels found in the literature for professional welders. Variable concentrations indicate that some individuals may not properly use the local exhaust ventilation system. Other possible explanation for variations are the position of the sampler on the shoulder, the time spent welding and in each welding position, and the skills of the welders. Strong relationships were observed between particle and metal concentrations, suggesting that these relationships could be used to estimate metal exposure in welders from particle exposure. Welding processes were the most important determinant of exposure in apprentice welders, with Metal Core Arc Welding producing the largest particle concentrations followed by oxyacetylene cutting, and Gas Metal Arc Welding. Health risk assessment showed that welder apprentices are at risk for overexposure to manganese, which suggests that professional welders should be monitored for manganese as they are exposed more than apprentices. Training in proper positioning of local exhaust ventilation system and proper use of respirators are recommended in training facilities.

This work reports porous carbonyl iron particles/multiwalled carbon nanotubes-polydimethylsiloxane composites (PCMCs) with high flexibility and low density. In comparison to the solid product, the porous PCMC possesses a larger elongation and deformation. Because of the excellent magnetic-mechanic-electric coupling performance, the flexible composite exhibits bimode sensitivity to both the external stresses and magnetic field. Typically, the normalized resistance variation (Δ R/ R) of PCMC reaches 82.8% and 52.2% when the compression strain and tension strain are 60% and 50%, respectively. Moreover, the Δ R/ R induced by bending, twisting, and magnetostress also changes remarkably. When a 144 mT magnetic field is applied, the Δ R/ R of PCMC increases with 3.6%. To further understand the magnetic-mechanic-electric coupling mechanism, a conductive network sensing model is proposed and analyzed. Finally, on the basis of the bimode PCMC sensor array, a smart chessboard which can precisely discriminate special chesses with different masses and magnets is developed. This study provides a new fabrication method for next-generation three-dimensional smart sensors toward artificial electronics and soft robotics.

This paper proposes a local edge extreme-based method to automatically measure the pitch length and surface braiding angle of braided preforms. The Lab space transform and an artistic edge and corn...

This work studied a flexible and stretchable magnetoactive elastomer (MAE) film consisting of carbonyl iron (CI) particles and polydimethylsiloxane (PDMS) elastomer matrix. The deformation of the MAE film was investigated using digital image correlation (DIC) and laser Doppler velocimetry (LDV) methods. The MAE film with free boundary is highly wrinkled under a magnetic field generated by an electromagnet with the current of 0.65 A. While in fixed boundary condition, the maximum deformation appears at the center point, and the maximum displacement reaches 0.63 mm when the current is 3 A. The finite element method (FEM) results demonstrate that the maximum internal stress and strain are 33 kPa and 2.3%, respectively. The FEM results are in good agreement with the DIC and LDV tests. With the exceptional magnetic controllability, the MAE film can find extensive applications in intelligent control systems, acoustic absorption devices, and haptics.

Nuclear magnetic resonance (NMR) spectroscopy is extensively used in analytical chemistry as a powerful, non-invasive, and non-destructive tool to elucidate detailed structures of small molecules in complex mixtures. A major initiative in NMR is the identification of metabolic changes in biological fluids, particularly urine, as potential biomarkers for specific diseases or occupational exposure. However, major challenges are encountered during data processing of complex NMR spectra, presenting obstacles in the use of NMR analysis in clinical applications. In this report, metabolite concentrations were determined using three different computational approaches with complex NMR spectra obtained using 33 replicates of quality control (QC) human urine samples. We have used a new computational method involving Monte Carlo (MC) simulation to automatically deconvolve and quantify metabolites in NMR spectra from human urine. MC simulation is independent of experimental bias or human error, and is recommended as the least biased approach to peak fitting for NMR spectra derived from human urine samples. We found that similar results could be obtained using MC simulation in urine samples compared with two previous approaches that are subject to experimental bias and/or human error.

The severe air pollution across China in the past several years has made the Chinese government recognize its significant impacts on public health and society, and take enormous efforts to improve the air quality all over the country, especially during the Twelfth Five-Year Plan (12th FYP). However, the overall effectiveness of these air pollution control policies remains unclear. In this study, we selected the 31 municipalities and provincial capital cities in mainland China as study settings. We collected the annual average population size, mortality rates (total mortality and mortality due to cardiovascular diseases, respiratory diseases, total cancer, lung cancer and breast cancer) and concentrations of air pollutants (PM10, PM2.5, SO2 and NO2) in each capital city from 2010 to 2015 from national or local Statistical Yearbooks. The effect sizes of air pollutants on mortality were obtained from previously published meta analyses or cohort studies. We first estimated the annual mortality rates attributed to the changes in air pollutant concentrations for every city in each year. Then, we further estimated the mortality benefits in the scenarios where the air quality had reached the grade II levels of Chinese Ambient Air Quality Standards (CAAQS) and World Health Organization (WHO) guidelines. In most capital cities, we observed dominant decreases in air pollutant concentrations during the 12th FYP, particularly from 2013 to 2015, which has led to significant mortality benefits for the public. A total of 121,658 deaths (0.441‰) have been prevented due to the decrease of PM2.5concentrations from 2013 to 2015 in all included cities. The morality benefits were larger in capital cities located in the key regions (the three main regions and ten city groups) than the other cities. In addition, more mortality benefits could be obtained in the future if the air quality reaches the grade II levels of Chinese Ambient Air Quality Standards (CAAQS) or WHO guidelines. We concluded that substantial mortality benefits achieved during the 12th FYP may be attributed to the improvements in China's air quality, which indicated the significant effectiveness of air pollution control policies.

This work reported a simulation study on the optimal diameter (D) and wall thickness (H) of hollow Fe3O4 microspheres to improve the magnetorheological (MR) effect. Modified formulae for the magnetic dipolar force, van der Waals force, and hydrodynamic drag force were employed in the simulation model. Typical evolution of shear stress and microstructures in steady shear flow was obtained. The shear stress-strain curve was divided into linear, fluctuant, and homeostasis regions, which were related to the inclination of particle chains and the lateral aggregation. For hollow Fe3O4 microspheres with different diameters and wall thicknesses, the shear stress curves collapsed onto a quadratic master curve. The best wall thickness was H = 0.39D for a 20 wt% MR fluid and H = 0.35D for a 40 wt% MR fluid, while the optimal diameter was D = 1000 nm and D = 100 nm, respectively. The maximum shear stress of the 40 wt% MR fluid was twice that of the 20 wt% MR fluid. The change of shear stress was due to the competition that results among the magnetic interaction, number of neighbors, tightness, and orientation of the particle chains. Simulated dimensionless viscosity data as a function of Mason number for various diameters, wall thicknesses, and weight fractions collapsed onto a single master curve. The simulated shear stress under both a magnetic field and shear rate sweep matched well with experiments.

The Acite ophiolitic melange represents a remnant of the Proto-Tethys forearc oceanic lithosphere. Two gabbros yield zircon 206Pb/238U ages of 510-512 Ma. The magmatic rocks are divided into three ...

A mechanically activated solid-state displacement reaction has been investigated as a means of manufacturing apatite nanoparticles. Mechanical milling and subsequent heat treatment of a CaCl 2 , Na 3 PO 4 and NaCl reactant mixture resulted in the formation of chlorapatite nanoparticles embedded within a solid salt matrix. The size and morphology of the chlorapatite nanoparticles was found to depend on the temperature of the post-milling heat treatment. A low temperature of 400 °C yielded largely equiaxed nanoparticles with an average diameter less than 100 nm. In contrast, heat treatment at 775 °C resulted in the formation of chlorapatite nanorods with an average diameter below 200 nm and a [001] growth direction. In both cases, removal of the salt matrix by washing with water gave powders with low levels of agglomeration.

Separation and recovery of metal ions with high value from industrial wastewaters is of significance due to the shortage of metal resources. A stable Al-based metal-organic framework (MOF-303) was used to selectively capture Cu2+ from Cu2+/Ni2+ and Cu2+/Co2+ binary systems. Due to the unique chelation effect of dual-pyrazol sites that are distributed parallel with the direction of the 1D channel, MOF-303 exhibited simultaneously a large capacity towards Cu2+ (330 mg g−1) and high separation selectivity (6076 and 2662 for Cu2+/Ni2+ and Cu2+/Co2+ respectively). The optimal pH for separation was found to 3.0–5.5, and the separation equilibrium was achieved at 3–4 h. Further, the recovery of the metals especially for Ni2+ and the regeneration of MOF-303 were achieved through a designed process. The Cu2+ selective adsorption mechanism based on the synergistic dual-pyrazol sites in MOF-303 was analyzed via a combination of experimental method and theoretical calculation. In conclusion, this work not only demonstrates MOF-303 is a promising adsorbent for the separation and recovery of the metals, but also highlights the unique dual-pyrazol sites in MOFs that can boost metal ions separation and recovery.

Surface braiding angle and pitch length are two important parameters for characterizing and evaluating the performance of three-dimensional braided composite preforms. In this paper a new method based on an improved curvature scale space corner detector with adaptive threshold is proposed for measuring these parameters, with applications to three-dimensional, four-directional carbon-fiber braided composite preforms. First, the original image is acquired using a system employing ‘dome light source + CCD camera + circular polarizing filter’. Second, the original image is processed using Lab transform and BM3D (block-matching and 3D filter). Third, the corners are detected using an improved curvature scale space corner detector with adaptive threshold. Finally, the pitch lengths and surface braiding angles are measured from the detected corners. Experimental results show that the proposed method can achieve automatic measurement of the pitch length and surface braiding angle with smaller average errors relative to manual measurements compared with alternative schemes.

In this work, a superparamagnetic fluid based on Fe 3 O 4 hollow nanospheres was developed and the influence of the particle structure on the rheological properties was investigated. The Fe 3 O 4 hollow nanospheres which were prepared by using the hydrothermal method presented the superparamagnetic characteristic, and the magnetic fluid thereof showed well magnetorheological (MR) effect. The stable magnetic fluid had a high yield stress even at low shear rate and its maximal yield stress was dramatically influenced by the measurement gap. In comparison to the Fe 3 O 4 nanoparticles based magnetic fluid (MF), the Fe 3 O 4 hollow nanospheres based MF exhibited better MR effect and higher stability since the unique hollow nanostructure. The shear stress of the hollow nanospheres is about 1.85 times larger than the nanoparticles based MF because it formed stronger chains structure under applying a magnetic field. To further investigate the enhancing mechanism, a molecule dynamic simulation was conducted to analyze the shear stress and the structure evolution of the Fe 3 O 4 hollow nanospheres based MF and the simulation matched well with the experimental results.

The two-tailed cationic surfactant dioctadecyldimethyl ammonium bromide (DODAB) produces semi-permanent coatings that yield strongly reversed electroosmotic flow (EOF), for example −0.31 ± 0.01 cm2 kV−1 s−1 at pH 3.5. Moreover, these coatings are easy to prepare, regenerable, cost effective, and yield high efficiency (520 000–900 000 plates per m) separations of cationic proteins over many runs under acidic (pH 3.5) conditions. Given the quaternary amine functionality of DODAB, we were surprised to observe that DODAB coatings become unstable at pH > 7. At pH 7.2, the EOF of a DODAB coated capillary drifted from reversed to cathodic over only 5 runs, and protein separations became severely compromised. By pH 12, no EOF reversal was observed. Electrophoretic and mass spectrometric studies demonstrate that the coating decomposition involves a surface conversion of the quaternary amine in DODAB to a variety of products, although the exact mechanism remains elusive. Regardless, the results herein demonstrate that semi-permanent coatings based on cationic two-tailed surfactants such as DODAB are limited to separations using acidic buffers.

This study focuses on the zircon U–Pb geochronology and geochemistry of intermediate–basic dikes from the Buqingshan–A’nyemaqen tectonic melange belt (BTMB) along the southern margin of the East Kunlun orogenic belt (EKOB). Zircons from a diorite dike show oscillatory zoning and relatively high Th/U ratios (0.47–2.43), indicating that they are of magmatic origin. Using LA–ICP–MS, zircons of the diorite dike yield a U–Pb age of 205 ± 1 Ma (MSWD = 0.88), implying that the diorite dikes were formed in the Late Triassic (Rhaetian) and also represented the latest tectonic magmatism in the BTMB. Geochemical analyses show that the rocks have low SiO2 (51.96–59.33 wt%), low Al2O3 (10.49–13.95 wt%), and low alkaline (4.00–5.29 wt.%), and thus belong to the subalkaline magma series. The contents of rare earth elements (REEs) are 80.23–189.19 ppm, with weakly negative to weakly positive Eu anomalies (δEu = 0.50–1.10). The trace element geochemistry is characterized by negative anomalies of Nb, Hf, P, Ti, and Sr and by positive anomalies of Th, La, Nd, Sm, Zr, and Eu. The diorite dikes, the product of a mafic magma formed at high temperature (~ 777 °C), were derived by partial melting of the mantle with possible admixture of crustal material. The intermediate–basic dikes in the BTMB are the products of mantle enriched upward and emplaced along tensional faults in the crustal–relaxation stage after the subduction–collision of the Bayan Har and East Kunlun Blocks during the Late Hercynian–Early Triassic.

The West Qinling Orogen (WQO) features widespread Triassic granitic rocks, which are crucial to constrain the tectonic evolution of the WQO. Here, we conducted an integrated petrological, geochronological, geochemical, and Sr-Nd-Hf isotope study on quartz diorites and mafic microgranular enclaves (MMEs) from the Ren’ai and Daerzang plutons, Hezuo area, WQO. The quartz diorites and MMEs have crystallization ages between 244 and 241 Ma. The quartz diorites display intermediate SiO2, high Mg# values (62–66) and evolved S-Nd-Hf isotope compositions, indicating an origin from magma mixing process. The MMEs display mineral compositions similar to those of the host rocks, only with more mafic minerals. The The Ren’ai and Daerzang plutons were part of the early Indosinian magmatic belt mainly distributed in the western and middle parts of the northern WQO. In comparison, late Indosinian magmatic rocks are mainly exposed in the eastern WQO. The asymmetric distribution of Early Mesozoic magmatism in the WQO might have been caused by a specific subduction pattern of the A’nimaque-Mianlue oceanic crust. The western and middle WQO experienced a period of flat or low angle subduction in the early stage, followed by slab rollback of the oceanic crust, which accounted for the flare-up of early Indosinian magmatism in the northern WQO. However, the distribution of late Indosinian magmatism might have been caused by asymmetric crustal delamination in the WQO.

The Neoproterozoic Hengdan Group in the northwestern margin of the Yangtze Block preserves archives for the debated early to middle Neoproterozoic (ca. 835–720 Ma) tectonic evolution of the margin of the Yangtze Block, and could potentially shed lights on the breakup mechanism of the Rodinia supercontinent. However, its depositional age, provenance and tectonic setting remain controversial. We address these issues through studies of petrography, geochemistry and detrital zircon U-Pb ages on the Hengdan Group sandstones. The Hengdan Group sandstones have low compositional and textural maturity and experienced low degree of chemical weathering and sediment recycling. They were mainly sourced from proximal acidic to intermediate arc-related igneous rocks, and their modal compositions, trace elemental contents (i.e., La, Ce, Th, and ΣREE) and ratios (i.e., LaN/YbN and Eu/Eu*) are comparable to those deposited in an active continental margin. Detrital zircons from the Hengdan Group sandstones yield similar unimodal age distributions at 950–740 Ma, with the youngest age clusters at ca. 730 Ma. Combining with previous work, the Hengdan Group was most likely deposited during ca. 733–717 Ma in a forearc basin and its primary provenance was probably from the nearby arc-related acidic to intermediate igneous rocks. In addition, the northwestern margin of the Yangtze Block was most likely in an active continental margin setting between ca. 835 and 720 Ma, and hence the slab retreating during a long-term oceanic subduction is favored as the dominant breakup driving force in the supercontinental margin(s).

The late Early Paleozoic volcanic rocks in the East Kunlun orogen are crucial to determining collisional processes related to the evolution of the Proto-Tethys Ocean. We report new zircon U-Pb ages, whole-rock geochemistry and Sr-Nd isotopes from these volcanic rocks and constrain their tectonic setting and magmatic processes. This volcanic suite consists mainly of foliated metarhyolites and minor metabasalts. Zircon U-Pb ages indicate that the bimodal volcanic rocks formed from Late Silurian to Early Devonian (ca. 420−409 Ma). The basalts show tholeiitic geochemical signatures characterized by low contents of SiO2 (47.19–54.83 %), MgO (2.21–7.52 %), and K2O/Na2O ratios (0.32−0.77%) and high contents of TiO2 (1.80–2.91 %). Their chondrite-normalized REE patterns are characterized by enrichments in LREEs (LREE/HREE = 3.68–6.09) with slight Eu anomalies (δEu = 0.67–1.00); their patterns are similar to the reference line of oceanic island basalt (OIB). The primitive mantle-normalized trace element diagram also shows similarities with OIBs and features overall enrichments in large ion lithophile and high field strength elements, except for Nb and Ta. The eNd(t = 422 Ma) values range narrowly from −1.79 to +1.32. These features suggest that the basalts were most likely derived from an asthenospheric mantle that was contaminated by small volumes of subcontinental lithospheric mantle (SCLM)/crust. The variations in major and trace elements show that the basalts experienced fractional crystallization of olivine, pyroxene and plagioclase. In contrast, the metarhyolites have high SiO2 (65.85–70.83 %), Na2O + K2O (6.71–10.09 %), K2O/Na2O ratios (1.69–2.80 %) and low MgO, Ni, and Cr contents. Their trace element signatures show enrichments in LILEs and LREEs (e.g. Cs, Rb, Ba), depletion of HFSEs (e.g. Nb, Ti, Ta) and high negative Eu anomalies. These features suggest a crustal origin lacking interactions with mantle melts. Considering all the geochemical and tectonic events of this area, it is concluded that the Maoniushan Formation volcanic rocks in EKOB formed in a postcollisional extensional setting related to asthenospheric mantle upwelling and continental delamination processes during the Late Silurian to Early Devonian. These tectonic-magmatic events, together with previous data, suggest that the Proto-Tethys Ocean had closed and evolved to postcollisional collapse stage since the Late Silurian.

A predominance of mantle peridotites over mafic rocks in the Tibetan Xigaze ophiolite distinguishes it from other classic ophiolites in the Tethyan belt, such as the Semail massif of Oman. Despite the abundance of new petrological, geochemical, geochronological and isotopic data on ophiolites that have accumulated over the last few decades, there is still no consensus on the tectonic setting and dynamic mechanisms of formation of these enigmatic bodies. This study involved detailed, large-scale mapping of the well-preserved Baimarang massif in the western part of the Xigaze ophiolite in order to provide key constraints on its tectonic setting.

The influence of the particle size on the rheological property of magnetic fluid was studied both by the experimental and computer simulation methods. Firstly, the magnetic fluids were prepared by dispersing Fe3O4 nanospheres with size varied from 40 nm to 100 nm and 200 nm in the solution. Then, the rheological properties were investigated and it was found that the relative magnetorheological effects increased with increasing the particle size. Finally, the molecular dynamic simulation was used to analyze the mechanical characteristics of the magnetic fluid and the chain-like model agreed well with the experimental result. The authentic chain-like structure observed by a microscope agreed with the simulation results. The three particles composed of the similar cluster nanostructure, thus they exhibited similar magnetic property. To this end, the unique assembling microstructures was the origination of the mechanical difference. And it was found that the higher MR (magnetorheological) effects of the large particle based magnetic fluid was originated from the stronger assembling microstructure under the applying magnetic field.

The Buqingshan Tectonic Melange Belt in the south margin of the East Kunlun Orogen, located in west section of Buqingshan–A'nyemaqen Suture Zone, is one of the key areas to understand continental tectonics and continental dynamics of China. This paper reports zircon U–Pb dating results and geochemistry of the Manite granodiorite (rock mass) in the Buqingshan Tectonic Melange Belt. Zircons from the granodiorite show oscillatory zoning structures and relatively high Th/U ratios, indicating that they are magmatic zircons. Zircon LA–ICP–MS U–Pb dating for the Manite granodiorite yields ages of 487 ± 11 Ma (MSWD = 2.3) and 479 ± 2 Ma (MSWD = 0.56), implying that the Manite granodiorite were formed in the Late Cambrian to Early Ordovician. Geochemical analyses show that the rocks have high contents of SiO2 (66.06 wt.%–68.60 wt.%) and Al2O3 (14.84 wt.%–16.54 wt.%), and low alkaline (6.17 wt.%–7.43 wt.%), belonging to the middle-K calc-alkaline series. The A/CNK (Al2O3/(CaO + Na2O + K2O)) ratios are 1.02–1.15, indicating that the granodiorite is weakly peraluminous. The contents of rare earth elements (REEs) are lower (89.64–130.41 ppm), with weakly negative to weakly positive Eu anomalies (δEu = 0.83–1.12). The primitive mantle-normalized trace elements are characterized by evidently negative anomalies of Nb, Ta, P, Hf, Ti, etc., and positive anomalies of Th, La, Nd, Zr, Eu, etc. Moreover, the rocks show features of typical I-type granite. This leads us to conclude that the Manite granodiorites is derived from the partial melting of crust and formed in an island-arc environment. Combined with previous studies, we believe that the subduction of the Proto-Tethyan Ocean in the Buqingshan area was ongoing during 487 to 479 Ma and formed island-arc-type granites represented by the Late Cambrian to Early Ordovician Manite granodiorite. Copyright © 2016 John Wiley & Sons, Ltd.

Uniform Co 3 O 4 @MoO 2 nanosheet arrays is fabricated through hydrothermal and electrodeposition method by virtue of the chemical-etching method. The electrochemical measurements show that the specific capacitance of 600 F g −1 at a scan rate of 2 mV s −1 for the Co 3 O 4 @MoO 2 hybrid is higher than both pristine MoO 2 and Co 3 O 4 . Moreover, the hybrid electrode with low resistance displays good cyclic stability of 83% retention after 1000-cycle charge/discharge. These results indicate that the as-prepared Co 3 O 4 @MoO 2 hybrid is a potential candidate used as electrode material in supercapacitors.

NiO with different morphologies were fabricated via hydrothermal method in different kinds of solvent. The morphology of the obtained NiO samples varied from nanoflakes to nanoparticles with the different volume ratios of water to ethanol. The electrochemical results showed that the specific capacitance of NiO-S5 obtained in ethanol was up to 1337.5 F g −1 at a current density of 0.62 A g −1 , which was greatly higher than that of the other samples. These results indicated that NiO-S5 had the superior electrochemical behavior which may be due to its small-size effect.

The Yangtianba Formation in the northwestern Bikou Terrane preserves sedimentary archives for the Early to Middle Neoproterozoic tectonic evolution of the northwestern margin of the Yangtze Block (YB). However, its provenance and depositional mechanism are still matter of debates. This paper presents geochronological and petrographic studies of two granite gravel samples and one coarse-grained sandstone sample as well as facies analysis of the conspicuous Yangtianba Formation conglomerates (YFC). The weighted average 206Pb/238U ages of the two granite gravels are 743 ± 6 Ma and 762 ± 4 Ma, respectively. The detrital zircon U-Pb ages of the sandstone sample peak at ca. 880 to 740 Ma, close to the depositional age of the Yangtianba Formation. Together with the dominantly angular to subangular morphology and clear oscillatory or broad zoning of these detrital zircons, the Yangtianba Formation is likely sourced from the Early to Middle Neoproterozoic igneous rocks. Facies analysis of the YFC shows they are stacked bundles of fining- and thinning-upward units of conglomerates-sandstone, suggesting a decreasing supply of coarse clastic materials from the episodic mass flow (debris flow) in the submarine channels rather than tillites. Combining with the previous work, the Yangtianba Formation probably mainly sourced from the Neoproterozoic igneous rocks in the Micangshan-Hannan area in the northwestern margin of the YB and is subaqueous sediment gravity flow deposits rather than glacial-marine deposits. These findings favor the model that the northwestern margin of the YB may be an active continental margin setting during the Early- to Middle- Neoproterozoic (ca. 835 to 720 Ma).

This work reported a carbon layer modified magnetite (Fe3O4) nanospheres (Fe3O4@C) which could be applied in preparing high performance magnetic fluid. The porous Fe3O4@C nanospheres were prepared by calcinating the Fe3O4@Polydopamine (Fe3O4@PDA) precursor in N2 atmosphere. The shear stress of Fe3O4@C-based magnetic fluid was as high as 24.9 Pa at saturated magnetic field, which was about 3.8 times larger than pristine Fe3O4-based magnetic fluid (6.6 Pa). Furthermore, the particle level dynamic simulation was employed to analyze the microstructure evolution and shear stress of Fe3O4@C-based magnetic fluid under applying an external magnetic field. The chain-like model well explained the magnetorheological (MR) mechanism and the simulation results matched perfectly with the experimental data. Since the crystallinity of Fe3O4 was improved during the pyrolysis, Fe3O4@C nanospheres possessed a higher saturation magnetization. The stronger magnetic dipolar forces and chain-chain interactions resulted in a much steadier Fe3O4@C chain-like structure. As a result, it was found that the superior MR performance and high stability of the Fe3O4@C-based magnetic fluid were originated from the core-shell and porous structures of Fe3O4@C. This work proposed a valuable magnetic particle model to prepare high performance magnetic fluid and further understand the origination of MR effects.

The granite is one of most widely distribution rocks in crust, and its petrogenesis is crucial to advance our knowledge of thermal condition in continental crust. The long-time tectonic evolution of crust in the active continental margin could be recorded by multi-stages of granitic assemblage. In order to reveal the subduction of Neo-Tethys and initial collision of Indian-Asian continents in eastern Tibetan Plateau, we selected the Early Paleocene to Early Eocene granitic rocks with associated enclaves in Tengchong Block, southeastern extension of Gangdese magmatic belt, to clarify their different derivation regimes using geochemical and isotopic compositions, mineral compositional variation. The zircon data show that Early Paleocene granites formed at 64 Ma, and Early Eocene granitic rocks formed at 54 Ma. Combing with the field contact relationship, the similar and enriched Sr-Nd-Pb and zircon Hf isotopic compositions indicate that the two stages of granitic rocks have a common and ancient lower crustal source. The enclaves in Early Paleocene granites could represent crystallization of coeval and cognate magmas at margin of magmatic conduit, but the enclaves in Early Eocene granitic rocks are products of magma mixing between mafic and felsic magma. According to rock assemblages and geochemical signatures of granitic rocks during Early Paleocene to Early Eocene in Tengchong Block, we propose that Early Paleocene granitic rocks are derived from partial melting of lower crustal rocks induced by long-lived heat accumulation with no or minimal basalt flux during the Neo-Tethyan subduction, whereas Early Eocene granitic rocks are derived from melting of crustal materials resulted from high mafic magma flux during Indian-Asian continental collision. The initial collision occurred at ca. 55 Ma.

The Hengdan Group in the northwestern part of the Bikou Terrane preserves sedimentary archives for the debated early to middle Neoproterozoic tectonic evolution of the northwestern margin of the Yangtze Block (YB), while its depositional age, provenance and tectonic setting remain controversial. This research has reported the geochemical and geochronological studies on the sandstones in the Hengdan Group. Our work indicates that the sandstones in the Hengdan Group experienced low degree of chemical weathering and sedimentary recycling, and are mainly sourced from acidic to intermediate igneous rocks. In addition, their elemental contents (i.e., La, Ce, Th and ΣREE) and ratios (i.e., LaN/YbN and Eu/Eu*) are comparable to those deposited in an active continental margin setting. All samples yield similar age distribution, having a dominated age range at ca. 850 to 720 Ma. Together with the dominantly angular to subangular morphology and clear oscillatory or broad zoning internal structure of these aged detrital zircons, indicating that the Hengdan Group should be proximally sourced from the early to middle Neoproterozoic igneous rocks. In addition, the youngest group of detrital zircon U-Pb ages of the sandstones in the Hengdan Group suggest that the onset and ending of the deposition of this group is later than ca. 741 Ma and ca. 722 Ma, respectively. Combining with previous work, the Hengdan Group was most likely deposited during ca. 741 to 717 Ma in a forearc basin setting at the northwestern margin of the YB, and with its primary provenance probably from nearby acidic to intermediate igneous rocks. In addition, all these above further supports that the northwestern margin of the YB should be a long-lived active continental margin setting during early to middle Neoproterozoic (ca. 835 to 717 Ma) and, the South China Block should be located at the relative peripheral location of the Rodinia supercontinent.

The degradation of lithium-ion batteries resulted from electrolyte decomposition may be indicated by the change in diffusion coefficient, De, and concentration, Ce. Although De and Ce are included in the liquid-phase diffusion process of a pseudo two-dimensional (P2D) model, these two important parameters are always inundated or contaminated when the complete P2D model is reduced. To obtain De and Ce reliably, a new parameter-lumped model of concentration overpotential, based on the reduced liquid-phase diffusion partial differential equation (PDE)in P2D model by Pade approximation, is developed with two main contributions. First, as the basis of Pade-based approximation, new analytic solutions of liquid-phase diffusion PDE are derived under the improved boundary conditions with the mass conservation principle. Second, in the proposed parameter-lumped model, the target parameters of De and Ce are grouped with other unknown but fixed parameters, respectively, which guarantees that even if the specific values of target parameters cannot be obtained, their changing trajectories can also be independently and effectively observed by lumped parameters. Finally, the simulation accuracies of reduced dynamic electrolyte concentration expressions are compared with that from other simplified methods, and the identification accuracy of the lumped parameters is verified under different working conditions.

Tunable and reversible dry adhesion has important applications in transfer printing, precision manufacturing, and intelligent robotics. In this paper, a novel composite pad is fabricated whose adhesion can be adjusted rapidly and reversibly by the magnetic field. The composite pad consists of a cylindrical polydimethylsiloxane (PDMS) shell and a magnetorheological polymer gel (MRPG) core. The mechanical properties of the MRPG core in the pads are sensitive to the magnetic field. So the adhesion of the composite pad can be changed due to the interface stress modulation by the magnetic field. The interface stress is calculated by using the finite element method to study the mechanism of magnetically controllable adhesion. The results show the smaller the edge stress, the larger the adhesion. So composite pads with four different core shapes are prepared to optimize the structure design. Pad-bump has the largest magnetically tunable adhesion interval. The adhesion of composite pads on uneven surfaces is also tested and the results show the adhesion of composite pads with soft cores is improved compared to the solid core pad. Finally, a magnetic field controlled pick-and-place demonstration experiment shows that the composite pad array has great application potential in magnetically controlled grabbing and release.

NiS/CoS/NiCo2S4 microflower with hierarchical structure is successfully prepared via facile hydrothermal method. The supercapacitive performance displays that the specific capacitance is up to 513 F g−1 at a scan rate of 1 mV s−1. The obvious redox peaks on the cyclic voltammetry curves reveal pseudocapacitive performance of NiS/CoS/NiCo2S4. Furthermore, the glucose detection behavior of NiS/CoS/NiCo2S4 modified electrode (NiS/CoS/NiCo2S4/GCE) has also been performed. Amperometric study indicates that this non-enzymatic sensor displays excellent electrocatalytic performance to glucose. The glucose diffusion from the solution to the electrode surface is the kinetic control process. These results indicate a potential application of NiS/CoS/NiCo2S4 for using as an electrode material in supercapacitors and glucose sensor.

A flexible self-powered magnetism/pressure dual-mode sensor, which consists of magnetorheological plastomer (MRP), was developed in this work. The working mechanism of the self-powered sensor was based on the displacement reaction of Fe and CuSO4. Different from traditional flexible pressure sensors, it was not only sensitive to a slight pressure (1.3 kPa), but also responsive to a small magnetic field (12 mT). Under an external magnetic field, the micro-scale carbonyl iron (CI) particles in the MRP electrode aggregated into the chain-like and the cluster-like structures, which enhanced the electrochemical activity of ions in the electrolyte of the electrode materials and formed the conductive network. The voltage increased with the magnetic field strength and the sensitivity was 4.2% at a 252 mT magnetic field. To further explore the mechanism of sensor, the microstructure evolution of CI particles inside the electrode materials under different magnetic fields was simulated by particle-level dynamics method. Finally, a smart writing board based on a self-powered magnetism/pressure dual-mode sensor array was developed and it was sensitive to different magnetic fields without an external power supply, which demonstrated a broad potential for mobile electronic device in the non-contact state.

Novel biotechnological approaches such as Metabolic Engineering (ME) and New Plant Breeding Techniques (NPBTs) are currently being developed to produce biological compounds for food and non-food products. NPBTs span a range of methods for in vivo production in crops, some of which are classified as GMOs while others aren't. Deploying such techniques will not only provide new opportunities for industry, but also challenges with respect to the regulatory environment. Similarly, the process of communicating these new techniques and their products to stakeholders and consumers will not be without its own challenges. We argue that scientists should engage more with non-scientists, either directly or through collaborators. These engagements should not only be about the science, we suggest, but also explicitly deal with real world ramifications, such as economic, environmental and social issues.

Biochar derived from waste biomass has proven as a promising sorbent for removal of heavy metals from wastewater. However, proper disposal of such a heavy metal-containing biochar is challengeable. The major objective of this study is to create a reuse way by converting the heavy metal-loaded biochar into supercapacitor. Two biochars were produced from dairy manure and sewage sludge, respectively, and subjected to sorption of Ni from solution, and then the Ni-loaded biochar underwent microwave treatments for fabrication of supercapacitor. The specific capacitance of biochar supercapacitor increased with Ni loading, especially the Ni-loaded biochar further treated with microwave in which the capacitance increased by over 2 times, compared to the original biochar supercapacitors. The increase of capacitance in the Ni-loaded biochar supercapacitor following microwave treatment was mainly attributed to the conversion of Ni into NiO and NiOOH, which was evidenced by X-ray diffraction and X-ray photoelectron spectroscopy. The biochar supercapacitors, especially microwave-treated Ni-loaded biochar supercapacitors exhibited the high stability of specific capacitance, with less than 2% loss after 1000 charge-discharge cycles. This study demonstrated that Ni-loaded biochar can be further utilized for generation of supercapacitor, providing a potential way for the reuse of exhausted carbonaceous sorbents.