Search

The development height of the water-conducting fracture zone (WCFZ) is crucial for the safe production of coal mines. The back-propagation neural network (BP-NN) can be utilized to forecast the WCFZ height, aiding coal mines in water hazard prevention and control efforts. However, the stochastic generation of initial weights and thresholds in BP-NN usually leads to local optima, which might reduce the prediction accuracy. This study thus invokes the excellent global optimization capability of the Improved Radial Movement Optimization (IRMO) algorithm to optimize BP-NN. The influences of mining thickness, coal seam depth, working width, and hard rock lithology proportion coefficient on the height of WCFZ are investigated through 75 groups of in situ data of WCFZ heights measured in the Jurassic coalfield of the Ordos Basin. Consequently, an IRMO-BP-NN model for predicting WCFZ height in the Jurassic coalfield of the Ordos Basin was constructed. The proposed IRMO-BP-NN model was validated through monitoring data from the 4−2216 working faces of Jianbei Coal Mine, followed by a comparative analysis with empirical formulas and conventional BP-NN models. The relative error of the IRMO-BP-NN prediction model is 4.93%, outperforming both the BP-NN prediction model, the SVR prediction model, and empirical formulas. The results demonstrate that the IRMO-BP-NN model enhances the accuracy of predicting WCFZ height, providing an application foundation for predicting such heights in the Jurassic coalfield of the Ordos Basin and protecting the ecological environment of Ordos Basin mining areas. [ABSTRACT FROM AUTHOR]

Pb and BHA in Pb-BHA-NaOL collector assembled by lead nitrate (Pb), benzohydroxamic acid (BHA), and sodium oleate (NaOL) with a 240:120:1 molar ratio in scheelite flotation have the common defects of flotation reagents including high cost, environmental pollution and reducing hydrometallurgy efficiency. Therefore, in this study, the efficient desorption and reuse of Pb and BHA adsorbed on the scheelite surfaces was first proposed. The desorption test results showed that 80.71% Pb and 70.93% BHA could be efficiently desorbed from the scheelite concentrate surfaces through strong stirring for 15 min at pH 13.0 and a speed of 1600 r/min. The reuse of the desorbed collector could save 67% Pb and 75% BHA. The results of desorption and reuse tests of the real ore also exhibited high feasibility in industrial application. Fourier transform infrared spectroscopy analysis revealed that Pb-O, C=O, and C-N groups of Pb and BHA adsorbed on the scheelite surfaces obviously weakened or disappeared. Atomic force microscopy analysis further confirmed that most of the Pb and BHA on the scheelite surfaces were removed. Therefore, this work not only solves the above defects of the collector but also provides a reference for the desorption and reuse of other flotation reagents. [ABSTRACT FROM AUTHOR]

The assembly quality of a complex product is the result of the combined effects of multiple manufacturing stages, including design, machining and assembly, and it is influenced by associated elements with complex coupling mechanisms. These elements generate and transmit assembly quality deviations during the assembly process which are difficult to analyze and express effectively. Current studies have focused on the analysis and optimization of the assembly surface errors of single or few components, while lacking attention to the impact of errors on the whole product. Therefore, in order to solve the above problem, an assembly quality deviation analysis (AQDA) model is constructed in this paper to analyze the deviation transfer process in the assembly process of complex products and to obtain the key features to optimize. Firstly, the assembly process information is extracted and the assembly quality network model is established on the basis of complex networks. Second, the Jacobian-Torsor (J-T) model is introduced to form a network edge weighting method suitable for the assembly process to objectively express the error propagation among product part features. Third, an error propagation model (EPM) is designed to simulate the error propagation and diffusion processes in the assembly network. Finally, the assembly process of an aero-engine fan rotor is used as an example for modeling and analysis. The results show that the proposed method can effectively identify the key assembly features in the assembly process of complex products and determine the key quality optimization points and monitoring points of the products, which can provide a decision basis for product quality optimization and control. [ABSTRACT FROM AUTHOR]

In this study, microcellular injection molding with the combination of the precision mold opening and rapid heat cycle mold technology is conducted to fabricate the 30% glass fiber reinforced polypropylene (PP/GF30) foam. By optimizing supercritical fluid, mold temperature, mold opening distance, and other process conditions, the injection‐molded PP/GF30 foam with a super high expansion ratio, density of 0.32 g cm−3, and porosity of 75%, is fabricated. The crystallization and rheological properties of the PP/GF30 samples are tested to determine the suitable injection molding parameters. The results show that glass fiber promotes the crystallization of polypropylene (PP) while improving its storage modulus and complex viscosity. The fiber distribution and orientation as well as the cellular structure are investigated by scanning electronic microscopy (SEM) and X‐ray computed tomography. Due to the high mold temperature, the shear effect and melt cavity filling are greatly changed. The oriented fibers in the core layer are randomly moved by the cell growth and presented as a scaffold to support the cell wall structure. The glass fiber increases the PP melt stiffness and avoids cell collapse so that the cellular structure with small cell size and even cell distribution is fabricated. The compression properties, surface roughness, and thermal conductivity are examined. [ABSTRACT FROM AUTHOR]

[Display omitted] The surface of minerals plays a pivotal role throughout the process of mineral beneficiation and utilization. Studies on surface properties, such as surface chemistries, of mineral phases of interest in real ores enable the selective separation of minerals, thereby enhancing the utilization of mineral resources. Nevertheless, obtaining specific mineral phases, especially for finely disseminated or poorly crystalized minerals, from real ores without altering their surface chemistries remains a challenge. The challenge also persists in investigating the same micro-scale mineral region in real ores using various surface characterization techniques, such as scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). This paper proposes a novel approach and procedures for locating micro-scale mineral regions of interest in real ores based on a three-dimensional coordinate system etched onto the ore surface using laser etching technology. A copper-nickel ore from Jinchuan, China, served as an illustrative example, with the finely disseminated chalcopyrite and pentlandite regions in the real ore sample being located and investigated using SEM and XPS. The approach presented in this study enables the in-situ detection of surface chemistries of specific mineral phase in real ores, ensuring the homogeneity and in-situ nature of the obtained surface chemistry data. This approach holds considerable promise, especially in the investigation of surface chemistries of minerals with fine dissemination and poor crystallization. [ABSTRACT FROM AUTHOR]

Crossplot is an important tool for data visualization analysis in well logging processing and interpretation. Generally, the color of the points in the crossplot is calibrated by the data to improve the plane crossplot from two dimensions (2D) to three dimensions (3D). However, this method is limited to the logging data. In many cases, it is necessary to use crossplots for comprehensive evaluation with the well logging, geology, mud logging, and oil testing data, or to deeply analyze the data from multiple wells and multiple layers. The traditional crossplots cannot meet the demands. To expand the traditional crossplot to multiple dimensions, we proposed an augmented-dimensional visualization and analysis method by the crossplot with multi-well and multi-dimensional heterogeneous data, which is developed based on the traditional crossplots. Firstly, we built the match matrix of the augmented-dimensional heterogeneous data from different depths and set up the crossplots of the heterogeneous data after depth normalization. In this way, the attribute calibrations of the points in the crossplots by logging data were realized, and the auxiliary figures of the augmented-dimensional crossplots were established. In addition, the crossplots were expanded to more dimensions by collaborative analysis of the multiple crossplots and synchronous display in different single-well and multi-well modules with the feature points projection. Secondly, we established the display method of the crossplots from multi-well data by quadtree index. The display and interaction performance of the augmented-dimensional crossplots under the conditions of large amount of data from multiple wells were greatly improved by optimizing the overlapped and covered points in the crossplots. This method can provide more information about the reservoirs and realize the comprehensive well logging comparison, analysis, and visualization from different views. It has been developed and integrated into a CIFLog software platform and has been widely used in many domestic oilfields. [ABSTRACT FROM AUTHOR]

Scheelite and calcite are usually intergrown calcium minerals that are separated via froth flotation. However, their selective separation remains difficult because of their similar surface properties. 2-phosphonobutane −1, 2, 4-tricarboxylic acid (PBTCA or H5L) is widely used in water treatment due to its low phosphorus content and efficient anti-scaling performance. With its excellent calcium-chelating ability, PBTCA was used as a novel depressant to selectively separate scheelite from calcite in this study. The flotation results of single mineral, binary mixed minerals, and real ore showed that PBTCA could selectively depress calcite at pH 9.0 using sodium oleate as collector. The results of zeta potential measurements, solution chemistry calculation, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculation indicated that the dominant form of PBTCA was L5-. This anion had a stronger adsorption on negatively charged calcite surfaces through electrostatic interaction. Higher Ca density and stronger Ca activity on calcite promote the adsorption of L5-. Moreover, the active O atoms in L5- could better match with two Ca sites on calcite in the interatom distance. Thus, PBTCA provides a new option for calcite depressants and has great industrial application potential. [ABSTRACT FROM AUTHOR]

This paper investigates the fault detection problem of instruments in process industry. Considering the difficulty of fault identification and the problems of multivariable and large computation complexity based on traditional kernel principal component analysis (KPCA), this paper presents a new method for fault detection and identification, which combines the coupling analysis with kernel principal component for multivariable fault detection and employed the local outlier factor (LOF) for multivariable fault identification. The new method consists of three parts. Firstly, according to nonlinear correlation of multivariable, coupling analysis and module division of variables based on detrended cross-correlation analysis (DCCA) are considered to reduce false alarm rate (FAR) and missed detection rate (MDR) in fault detection and identification. Secondly, KPCA is employed to detect fault in each sub-module of variables. Finally, for the sub-module which has the fault detected in second step, the LOF is adopted to calculate abnormal contribution of each variable in sub-modules to realize fault identification. To prove that the new method has the better capability of processing multivariable fault detection and the more accuracy rate on fault detection and identification than the conventional methods of KPCA, a case study on Tennessee process is carried out at the end. [ABSTRACT FROM AUTHOR]

Efficient electrode-electrolyte interaction is vital prerequisite for capacitive performance of supercapacitor. Herein, a novel capacitive system is proposed based on bare Ni foam electrode and ferricyanides (equal molar K 3 Fe(CN) 6 /K 4 Fe(CN) 6 pair) mediated alkali electrolyte free of any active electrode material. The efficient electrode-electrolyte interaction enables high faradic capacitance, considerable cycleability and slow self-discharge behavior. The hybrid supercapacitor based on the Ni foam electrode-ferricyanides electrolyte positive half-cell and activated carbon negative electrode delivers high energy, power and excellent cycleability, manifesting the significance of electrode-electrolyte interaction to capacitive performance. Image 1 • A facile bare Ni foam electrode-redox electrolyte capacitive system was proposed. • Efficient electrode-electrolyte interaction leads to high capacitive performance. • The hybrid supercapacitor based on this capacitive system offers high energy density. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Electrode material is the key component of a supercapacitor, the highly accessible surface area, efficient electrons/ions migration channels, robust structural stability and redox activity of electrode material are pivotal prerequisites for harvesting optimal capacitive performance. Herein, a ternary cobalt hydroxide carbonate-nickle hydroxide-reduced graphene oxide composite (CN-rGO) with porous nanowire arrays architecture was deposited onto Ni foam substrate through confined hydrothermal reaction directed by surfactant micelles. The as-prepared CN-rGO nanowire arrays exhibit mesoporous texture with high specific surface area, which allows sufficient soaking of electrolyte with short diffusion path length. Additionally, the vertically aligned nanowires with incorporation of reduced graphene oxide offer efficient channels for migration of electrons generated by faradic components. Both features enable the sufficient faradic reactions and charge storage of the CN-rGO electrode. Under optimal Co:Ni feeding molar ratio of 7:3, the battery typed faradic CN-rGO electrode offers superior specific capacitance (2442 F g−1 at 1 A g−1), good rate capability (65% capacitance retaining ratio within 1–20 A g−1) and cycling stability (70% maintaining ratio after 2000 charge-discharge cycles). When used as faradic electrode of hybrid supercapacitor (HSC), balanced energy density (42.9–26.2 Wh kg−1), power density (393–3519 W kg−1) and cycleability (80% initial capacitance maintaining ratio undergoes 5000 charge-discharge cycles) can be delivered simultaneously, highlighting the potential of the micelles directed CN-rGO nanowire arrays electrode in efficient energy storage device. [ABSTRACT FROM AUTHOR]

Highlights • Surface broken bonds can be used to assess surface properties of fluorite. • A surface with lower broken bond density shows a high exposure in particles. • A surface with higher broken bond density exhibits a faster dissolution. • The broken bond method is helpful for mineral/material chemistry research. Abstract Crushing and grinding, the prerequisite processes in many industries, are employed in areas such as minerals processing and powder technology. During these processes, minerals will cleave or fracture along specific crystal directions, where there are weak inter-planar bonds, generating exposed surfaces. On an exposed mineral surface, different ions can possess different numbers of broken bonds. The total number of broken bonds of all ions on the exposed surface can be considered as the number of broken bonds of the exposed surface. The broken bonds on the exposed surface make the latter more active and determine its reactivity. The broken bond density on the exposed surfaces of fluorite was calculated, enabling the anisotropic surface reactivity of fluorite such as surface energy, surface relaxation, dissolution, wettability, surface charge and adsorbability to be revisited. The results show that the surface broken bond density, which is related to the specific surface energy, could be used to predict the cleavage nature, surface relaxation degree, dissolution rate and surface stability of fluorite crystal. The distribution feature and the number of broken bonds of exposed active ions (such as Ca2+ for fluorite) can be used to predict and explain the anisotropic surface wettability and surface charge, as well as the adsorption mode and strength of organic molecule binding to different exposed surfaces. The calculation of surface broken bonds can serve as useful method to assess mineral surface chemical behavior. This approach is helpful for mineral/material chemistry research in general. [ABSTRACT FROM AUTHOR]

Metal ions are commonly used as activators to improve the anionic collector flotation of oxide minerals with an accepted activation mechanism that the prior addition of metal ions can adsorb onto the oxide mineral surface to increase the number of active sites for subsequent attachment of a collector. The improved flotation of cassiterite (or scheelite) with the use of lead nitrate (LN) as the activator and benzohydroxamic acid (BHA) as the collector is a typical example. However, our recent research showed that a soluble metal-organic complex (lead-BHA complex) produced by pre-mixing LN and BHA further improved the collecting ability and selectivity in the flotation of cassiterite and for that, the existing activation mechanism cannot completely explain this further improved performance. We believe that the lead ion and its hydroxide species can directly interact with water molecules to form Pb(H 2 O) n 2+ and Pb(OH)(H 2 O) n + complexes in water solution, and those bonded water molecules will in turn affect the interaction of (hydroxide) lead ion with the cassiterite surface and the BHA. In this work, solution chemistry calculation was used to identify the major active components of the lead-BHA complex in water solution at different pH levels, and based on density functional theory, the adsorption energies of different activation mechanisms were calculated via accurate first-principle calculations, indicating a much stronger interaction of the adsorption of HO-Pb-BHA complex on cassiterite surface (−48.11 kcal/mol) compared with that of the sequential adsorption of Pb(OH)(H 2 O) 5 + and BHA anion (−13.29 kcal/mol) at optimal flotation pH 8–9. That is, the difference in two activation systems can be explained based on thermodynamics. With such, a new hypothetic activation model was proposed to explain the improved performance of soluble lead-BHA complex and then, the proposed model was verified by the flotation experiment and adsorption test results. This work can help enrich the activation theory of metal ions in anionic collector flotation of minerals. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Much rounder ball mill fluorite particles with more exposure of {1 1 1} surface. • More elongated rod mill particles with more {1 1 0} and {3 1 0} surfaces exposed. • A higher monolayer coverage degree of oleate on rod mill particles. • Exposure degree of crystal surfaces affects the shape factors of fluorite particle. Abstract Grinding for mineral liberation is a prerequisite for a successful flotation separation and different grinding media produce mineral particles with different morphologies and surface properties. In this paper, a systematic investigation was carried out on surface physicochemical properties of fluorite particles produced by ball and rod mills through such methods as single mineral flotation experiment, wettability measurement, X-ray diffraction (XRD) test and scanning electron microscopy (SEM) observations. XRD and SEM observations indicate that the predominant surfaces exposed for both mill particles follow the order of {1 1 1} > {1 1 0} > {3 1 0} > {1 0 0} surfaces. The difference lies in that the rod mill particles possess a higher exposure of more reactive {1 1 0} and {3 1 0} surfaces of higher calcium-atom reactivity, which show a stronger interaction with the collector and hence a higher monolayer coverage degree. This difference also leads to a higher elongation and lower roundness values of rod mill particles that are beneficial to the particle-bubble attachment by shortening the induction time. The results of wettability and flotation show that when treated with the collector solution, the particles produced by rod mill possess a lower critical surface tension and greater hydrophobicity, hence exhibiting a higher flotation recovery. This study signifies the importance of the exposure of crystal surfaces in determining the shape factors and reactivity of mineral particles, which will help to guide the optimization of flotation separation and particle surface modification. [ABSTRACT FROM AUTHOR]

Poor cycleability is the main shortage of faradic supercapacitors, which can be generally improved by the compositing or coating with flexible and conductive auxiliary components. Herein, reduced graphene oxide (rGO) coated CoNi 2 S 4 grown onto Ni foam substrate was synthesized by a two-step hydrothermal strategy. The rGO coating apparently improved the cycleability of the CoNi 2 S 4 electrode without sacrificing total capacitance, therefore resulted in efficient and long lifetime energy storage device. The rGO coated CoNi 2 S 4 electrode, denoted as CoNi 2 S 4 -rGO electrode, demonstrated a specific capacitance ( C s ) of 1680 F g -1  at 1 A g −1 and considerable rate capability (62% capacitance retaining ratio within 1–20 A g −1 ). More importantly, the cycleability of the CoNi 2 S 4 -rGO electrode enhanced by 46% relative to the mere CoNi 2 S 4 electrode after 5000 charge-discharge cycles, which is mainly due to the inhibition of shedding of faradic CoNi 2 S 4 from electrode by rGO coating. When used as positive electrode of asymmetric supercapacitor (ASC), the CoNi 2 S 4 -rGO//porous carbon supercapacitor delivered an energy density of 51.7 Wh kg −1 at 762 W kg −1 , and 60.5% of its initial capacitance was maintained after 5000 charge-discharge cycles. The balanced energy, power densities and cycleability highlight the potential of the rGO coated faradic electrode in energy storage devices. [ABSTRACT FROM AUTHOR]

We analyzed the prevalence and genotypes of Parechovirus A (PeV-A) in children with diarrhea in Beijing, China, 2017–2019. A total of 1734 stool samples collected from children <5 years of age with diarrhea were tested for the presence of PeV-A. Viral RNA was detected by real-time RT-PCR, and then genotyped by nested RT-PCR. We detected PeV-A in 93 (5.4%, 93/1734) samples, of which 87 could be genotyped by amplification of either the complete or partial VP1 region or the VP3/VP1 junction region. The median age of PeV-A infected children was 10 months. Most PeV-A infections were observed between August and November, with a peak in September. Seven known genotypes of PeV-A1A, -A1B, −A3, −A4, −A6, −A8 and -A11 were detected and PeV-A1B was the most prevalent genotype. Coinfection with other diarrheal viruses was observed in 30.1% (28/93) of PeV-A positive samples. All strains of PeV-A1A, -A1B, −A4 and -A6 obtained in this study contained the arginine-glycine-aspartic acid (RGD) motif, while all strains of PeV-A3, −A8 and -A11 lacked it. This study revealed a high genetic diversity of PeV-A circulating in Beijing and PeV-A11 was reported for the first time in children with diarrhea in China. • A total of 1734 stool samples were detected, and 93 samples (5.4%) were positive for PeV-A. • Based on VP1 genes and VP3/VP1 junction region genes, 79 and 72 strains were genotyped successfully, respectively. • Seven known genotypes of PeV-A1A, -A1B, −A3, −A4, −A6, −A8 and -A11 were detected. • PeV-A11 was reported for the first time in children with diarrhea in China. [ABSTRACT FROM AUTHOR]

In the field of mineral processing, the successful flotation of target minerals requires sufficient liberation through grinding. The aim of this paper is to compare and evaluate the performance of ball versus short cylindrical media for comminution of dolomite by point and line contact, respectively. The results of the grinding experiments indicate that short cylinders generate more angular particles with intermediate sizes and exhibit a higher grinding efficiency compared to balls. The Population Balance Model demonstrates the distribution of broken fragment sizes during the breaking stage for each size range. The results of the DEM (discrete element method) grinding simulation are consistent with the experimental findings in terms of the distribution of particle sizes, the shape of the particles, and the distribution of broken fragment sizes. Furthermore, short cylinders selectively produce more active {104} crystal surface of dolomite, which possess a higher adsorption capacity with collectors and are preferentially floated as the concentrate. In reverse flotation for removal of dolomite, tests confirm that the products obtained from grinding with short cylinders exhibit a higher flotation recovery of dolomite compared to those obtained from ball grinding. This study provides a reference scheme for optimizing the grinding and flotation processes of valuable minerals. [ABSTRACT FROM AUTHOR]

Faradic electrodes with large specific surface areas, efficient electrons/ions migration channels and high redox activities are essential prerequisites for high performance supercapacitors. Herein, highly porous Co 3 S 4 @Ni 3 S 4 heterostructure arrays were prepared onto Ni foam substrate by a facile two-step hydrothermal route for application as supercapacitor electrode. Because of the novel core-sheath heterostructure with vertically aligned porous nanowires arrays and macroporous channels, the Co 3 S 4 @Ni 3 S 4 electrode can offer high electrons/ions mobilities and large specific surface area, therefore enables an areal capacitance ( C A ) of 3.6 F cm −1 at 0.8 mA cm −2 and 80% initial C A maintaining ratio undergoes 5000 consecutive charge-discharge cycles. When used as positive electrode of hybrid supercapacitor, the lightweight Co 3 S 4 @Ni 3 S 4 //porous carbon hybrid supercapacitor delivers an areal capacitance of 0.513 F cm −2 at 2 mA cm −2 and moderate rate capability, therefore can deliver areal energy densities of 0.19–0.021 mWh cm −2 within areal power density range of 1.72–38.4 mW cm −2 , good cycleability and slow self-discharge behavior. The current Co 3 S 4 @Ni 3 S 4 heterostructure arrays electrode paves a feasible avenue to improve the capacitive performances of supercapacitors through construction of hierarchically porous nanoarrays architectures. [ABSTRACT FROM AUTHOR]

Fluorescent carbon dots (CDs) were synthesized through hydrothermal treatment of an easily available fish scales precursor. The as-prepared CDs exhibit good water-solubility, wavelength-tunable fluorescence nature with fluorescence quantum yield of 9%, high photostability and resistance against common ions and biomolecules, thus enables the application as viable fluorescent nanoprobes for detection of pharmaceuticals molecules. The fluorescence of CDs can be efficiently quenched by lidocaine hydrochloride (LH) through static quenching, hence the CDs can serve as a simple and rapid fluorescent probe for determination of LH pharmaceutical. The fluorescent CDs probe demonstrated a wide linear range (0.185–1.295 mmol L −1 ) and a low detection limit (0.054 mmol L −1 ). The CDs also demonstrates low cytotoxicity, which enables the accurate fluorescent detection of LH in human serum. [ABSTRACT FROM AUTHOR]

ZnCo 2 O 4 -rGO composite with intertwined sheets grown onto nickel foam substrate is prepared through a facile hydrothermal deposition and followed thermal annealing treatment, which can be directly employed as binder free electrode of supercapacitor. The hierarchically porous texture of ZnCo 2 O 4 -rGO composite with high specific surface area and efficient ions diffusion channels ensures sufficient faradic reaction of ZnCo 2 O 4 component, therefore enables an ultrahigh electrode specific capacitance ( C s ) of 3222 F g −1 at 1 A g −1 in alkali electrolyte, and the C s still retains to be 860 F g −1 at 20 A g −1 . When used as positive electrode of full cell, the ZnCo 2 O 4 -rGO//activated carbon (AC) asymmetric supercapacitor can offer a maximum device specific capacitance ( C cell ) of 139 F g −1 at 0.5 A g −1 and therefore an energy density ( E cell ) of 49.1 Wh kg −1 at power density ( P cell ) of 400 W kg −1 . Even at high P cell of 7625 W kg −1 , the E cell of the asymmetric device can still retain to be 18.8 Wh kg −1 . More significantly, the asymmetric supercapacitor demonstrates only 6% C cell fade subjected to 5000 successive charge-discharge cycles. The balanced E cell , P cell delivery abilities and high cycleability highlight the potential of the faradic ZnCo 2 O 4 -rGO composite in high performance and long lifetime energy storage devices. [ABSTRACT FROM AUTHOR]

Fluorite, a chief source of fluorine in the nature, usually coexists with calcite mineral in ore deposits. Worldwide, flotation techniques with a selective collector and/or a selective depressant are commonly preferred for the separation of fluorite from calcite. In the present study, an attempt was made to use benzhydroxamic acid (BHA) as a collector for the selective separation of fluorite from calcite without using any depressant. Results obtained from the flotation experiments for single mineral and mixed binary minerals revealed that the BHA has a good selective collecting ability for the fluorite when 50 mg/L of BHA was used at pH of 9. The results from the zeta potential and X-ray photoelectron spectroscopy (XPS) indicated that the BHA easily chemisorbs onto the fluorite as compared to calcite. Crystal chemistry calculations showed the larger Ca density and the higher Ca activity on fluorite surface mainly account for the selective adsorption of BHA on fluorite, leading to the selective separation of fluorite from calcite. Moreover, a stronger hydrogen bonding with BHA and the weaker electrostatic repulsion with BHA − also contribute to the stronger interaction of BHA species with fluorite surface. [ABSTRACT FROM AUTHOR]

Nitrogen doped porous carbons (NCs) with high specific surface areas, moderate graphitization degree and high N contents were synthesized by pyrolysis of melamine sponge-polyaniline composite. The as-prepared NCs demonstrate considerable capacitive performances in acidic electrolyte. More importantly, the NCs demonstrated high catalytic activity for the redox reaction of iodides in acidic electrolyte, thus enabled prominent pseudocapacitance via the faradic reaction of redox electrolyte. Under the optimal concentration of KI in acidic electrolyte, the electrode specific capacitance achieved 616 F g −1 , which is 3 folds higher over that in solely acidic electrolyte. High cycling performance was also maintained for the avoidance of volumetric variation of electrode during charge–discharge cycles. The current work proposed a viable way to ameliorate the capacitive performance via the catalytic NCs electrode-redox iodide electrolyte system. [ABSTRACT FROM AUTHOR]

The efficient separation of scheelite from calcium-bearing minerals, especially calcite, remains a challenge in practice. In this work, a novel reagent scheme incorporating a depressant of sodium hexametaphosphate (SHMP) and a collector mixture of octyl hydroxamic acid (HXMA-8) and sodium oleate (NaOl) was employed in both single and mixed binary mineral flotation, and it proved to be highly effective for the separation. Furthermore, the role of the pH value in the separation was evaluated. Additionally, the mechanism of the selective separation was investigated systemically via zeta potential measurements, fourier transform infrared (FTIR) spectroscopy analysis, X-ray photoelectron (XPS) spectroscopy analysis and crystal chemistry calculations. It turns out that the selective chemisorption of SHMP on calcite (in the form of complexation between H 2 PO 4 − /HPO 4 2− and Ca 2+ ) over scheelite is ascribed to the stronger reactivity and higher density of Ca ions on the commonly exposed surfaces of calcite minerals. The intense adsorption of HXMA-8 on scheelite over calcite due to the match of the O O distances in WO 4 2− of scheelite and CONHOH of HXMA-8 holds the key to the successful separation. We were also interested in warranting the previous claim that NaOl is readily adsorbed on both minerals via chemisorption. Our results provided valuable insights into the application of mixed collectors and an effective depressant for flotation separation. [ABSTRACT FROM AUTHOR]

The enhancement of energy density at high power density is highly desired in design of supercapacitor, which relies on the electrochemically accessible electrode area, electrons/ions diffusion channels of electrodes and the device assembly manner. Herein, graphitized and porous fullerene carbon soot is used as matrix for preparation of activated carbon (denoted as a-FC). The high specific surface area, hierarchical pore sizes and moderate graphitization degree of a-FC enable balanced specific capacitance, rate capability and cycleability. Meanwhile, graphene-Co 3 O 4 composite (GC) with cross-linked porous Co 3 O 4 nanofibers array onto graphene sheet is hydrothermally deposited on Ni foam substrate. The pseudocapacitive GC electrode can offer superior capacitance (1935 F g −1 at 5 A g −1 ), rate capability (68% capacitance retaining ratio within 0.5–50 A g −1 ) and considerable cycleability (17% capacitance decline within 2000 charge-discharge cycles) comprehensively. Furthermore, the asymmetric supercapacitor based on the a-FC and GC electrodes delivers balanced energy density (50.3–20.9 Wh kg −1 ), power density (786–12128 W kg −1 ) and cycleability (77% initial capacitance maintaining ratio within 5000 charge-discharge cycles), highlighting the potential in efficient energy storage device. [ABSTRACT FROM AUTHOR]

Grinding for mineral liberation is a prerequisite for a successful flotation separation. Different grinding media produce mineral particles with different surface properties and flotability. In this study, the surface properties and flotation behavior of scheelite particles having a size of − 74 + 38 μm produced by ball and rod mills were studied through single mineral flotation experiment, scanning electron microscopy (SEM) observation, wettability measurement, and X-ray diffraction (XRD) test. The wettability and flotation results showed that, compared to the ball mill particles, the rod mill ones have a lower critical surface tension and thus a greater hydrophobicity when treated with the collector solution, and accordingly perform a better flotation recovery using oleate as the collector. In addition, the rod mill particles have a smaller specific surface area, so the full monolayer adsorption of the collector on their surfaces is achieved at a lower oleate concentration. The SEM analysis further confirmed that mineral grains obtained from the rod mill possess larger elongation and flatness values, which are essentially required for their attachment with air bubbles. The XRD observations revealed that mineral particles from both mills (i.e. ball and rod) have similar exposure intensity of abundant {112} surface. However, the rod mill particles have more {101} surface exposed, while the ball mill particles have more {001} surface exposed, leading to a stronger interaction of the collector with the rod mill particles. Keeping in view the stronger interaction with the collector and the easier attachment to air bubbles, the rod mill scheelite particles are deemed to be more hydrophobic and have a higher flotation recovery. These details studied will help establish the relation between the particle surface properties and the grinding media, and provide guidance for optimizing flotation separation. [ABSTRACT FROM AUTHOR]

CHS is a rare immunodeficiency syndrome with defects in the functions of cytotoxic cells and neutrophils. Approximately 85% of patients with CHS undergo an AP within the first decade, which is similar to FHLH. Chemotherapy could induce transient remission, but only allogeneic HCT could correct the underlying genetic defect and prevent relapse. We reported a case of CHS diagnosed at 19 months, who had an elder brother who had previously succumbed to the same disease. The little girl presented with severe AP manifestations including recurrent high fever, enlarged superficial lymph nodes, and extraordinary hepatosplenomegaly occupying the whole abdominal and pelvic cavity. Comprehensive therapies including HLH 2004 protocol, supportive care, and antibiotics, especially antituberculous agents, were given to her to induce remission. After remission, the patient received fully HLA-matched UCBT. The transplantation course was uneventful, except for fluctuation of donor chimerism. The patient has been alive for 36 months without infection and neurologic manifestations and is under further follow-up. Our result provides another case that UCBT can be effective for treating patients with CHS and remission before HCT is important for good prognosis. [ABSTRACT FROM AUTHOR]

In situ leaching of weathered crust elution-deposited rare earth ore usually uses ammonium sulfate as the leaching agent, which poses challenges such as low mass transfer efficiency, high consumption of the leaching agent and long leaching periods. In order to intensify the leaching process of rare earth elements and reduce the impurity of leaching accompanying rare earth, ammonium sulfate and ammonium formate were mixed as a novel compound leaching agent to treat weathered crust elution-deposited rare earth ore. The effects of ammonium formate concentration, liquid/solid ratio, leaching agent pH and leaching temperature on the leaching process of rare earth (RE) and aluminum (Al) were investigated and evaluated using the chromatographic plate theory. Results showed that ammonium formate could effectively enhance the mass transfer efficiency of rare earth and significantly inhibit the mass transfer efficiency of aluminum. Leaching agent pH has a greater impact on the mass transfer efficiency of aluminum. A higher leaching temperature could enhance the mass transfer efficiency of rare earth and aluminum by providing a driving force to overcome the resistance of diffusion. The optimum conditions for leaching rare earth and aluminum are 0.1 mol/L ammonium sulfate compounded with 0.032 mol/L ammonium formate, pH 4–8 of the leaching agent, 0.8:1 liquid:solid (mL/g) ratio and room temperature. Under this condition, the mass transfer efficiency of rare earth was improved, and the mass transfer efficiency of aluminum was significantly inhibited. [ABSTRACT FROM AUTHOR]

The anisotropic physicochemical properties of calcite, including cleavage nature, surface (free) energy, surface relaxation degree, wettability and adsorption behaviour, were revisited in this paper based on the surface structures and surface broken bonds reported previously. The relationships between these surface properties were also discussed. The analysis indicated that the positive relationship between the density of surface broken bonds and the surface energy of calcite was established, and the former could be used to predict the cleavage nature, commonly exposed surfaces and the degree of surface relaxation. The distribution characteristic and the number of broken (or unsaturated) bonds of surface Ca atoms can be used to explain the anisotropic surface wetting and adsorption behaviour of calcite. This review demonstrated that surface broken bonds could be a fast way to study the surface properties of minerals and materials. [ABSTRACT FROM AUTHOR]

The design of efficient non-Pt counter electrode (CE) materials is highly desired in field of dye sensitized solar cell (DSC). Herein, by combining the catalytic features of N doped carbon (NC) and CoNi alloy, CoNi alloy incorporated porous N doped carbon hybrid (CoNi-NC) is synthesized for application as catalytic CE of DSC. Benefiting from the proper meso-/macroporosity with high electroactive surface area, the CoNi-NC electrode demonstrates apparently higher electrocatalytic activity for iodine reduction reaction (IRR) over pyrolyzed Pt electrode. As a consequence, the DSC based on CoNi-NC CE yields a power conversion efficiency ( PCE ) of 7.6%, which is superior over that of Pt CE based cell (7.2%), highlighting the bright potential of CoNi-NC in efficient and economical CE of DSC. [ABSTRACT FROM AUTHOR]

Graphene incorporated, N doped activated carbons (GNACs) are synthesized by alkali activation of graphene-polypyrrole composite (G-PPy) at different temperatures for application as electrode materials of supercapacitors. Under optimal activation temperature of 700 °C, the resultant samples, labeled as GNAC 700 , owns hierarchically porous texture with high specific surface area and efficient ions diffusion channels, N, O functionalized surface with apparent pseudocapacitance contribution and high wettability, thus can deliver a moderate capacitance, a high rate capability and a good cycleability when used as supercapacitor electrode. Additionally, the GNAC 700 electrode demonstrates high catalytic activity for the redox reaction of pyrocatechol/o-quinone pair in H 2 SO 4 electrolyte, thus enables a high pseudocapacitance from electrolyte. Under optimal pyrocatechol concentration in H 2 SO 4 electrolyte, the electrode capacitance of GNAC 700 increases by over 4 folds to 512 F g −1 at 1 A g −1 , an excellent cycleability is also achieved simultaneously. Pyridinic- N is deemed to be responsible for the high catalytic activity. This work provides a promising strategy to ameliorate the capacitive performances of supercapacitors via the synergistic interaction between redox-active electrolyte and catalytic electrodes. [ABSTRACT FROM AUTHOR]

Simultaneous improvement in capacitance, rate capability and cycleability of electrode material is highly desired for high-performance supercapacitor, which necessitates the rational design of pore texture and surface composition of electrode materials. Herein, graphene incorporated activated carbon is synthesized by pyrolysis and alkali activation of graphene oxide-egg white (EW) precursor. The 3-dimensionally intertwined graphene mat induces the coating of EW and constructs hierarchical porosity of the resultant activated carbon. Benefit from the interconnected large mesopores/macropores channels deriving from the robust and conductive graphene mat, abundant micropores/small mesopores with slightly enlarged pore width by activation treatment, as well as the essential pseudocapacitance stemming from the N, O functionalities, high electrons/ions conductivities and considerable capacitance can be ensured. As a result, dramatically enhanced overall capacitance can be offered under higher current densities and consecutive charging-discharging cycles. The sample prepared by graphene incorporation and activation treatment of EW precursor, labeled as AGEWC, delivers a specific capacitance of 291 F g −1 at 1 A g −1 in 1 M H 2 SO 4 electrolyte, a dramatically improved rate capability (69% capacitance maintaining ratio within 0.5∼15 A g −1 ) and a high cycleability (90% capacitance retention after 5000 charge-discharge cycles). The present work provides a low cost while efficient strategy to comprehensively optimize the capacitive performances of activated carbon based supercapacitors. [ABSTRACT FROM AUTHOR]

Sodium oleate (NaOl) has been widely used as a collector for the scheelite flotation. However, low selectivity of NaOl and large amount of sodium silicate (SS) needed remain tough problems. In this study, octyl hydroxamic acid (HXMA-8) was used as an associate collector with NaOl in scheelite flotation. The flotation tests showed that a novel reagent scheme, i.e., a lower dosage of SS (300 mg/L) and mixed collectors of HXMA-8 + NaOl (total concentration 4.5 × 10 − 4 mol/L, preferred mass ratio of 1:2) achieved the selective separation of scheelite from calcite. Zeta potential measurements indicated that the depressant, SS, adsorbed more strongly on calcite surface than on scheelite surface. HXMA-8 adsorbed significantly on scheelite surface either in the absence or presence of SS by chemical bonding between oxygens of HXMA-8 and surface metal ions. NaOl also adsorbed on both mineral surfaces by chemisorption, but the adsorption on calcite surface was influenced adversely by the presence of SS. [ABSTRACT FROM AUTHOR]

• The quantum chemistry assisted screening of flotation reagents is accurate and feasible to oxide minerals. • The reaction-free energy can be a useful indicator of interface bonding intensity between collectors and surface targets. • The screened n -octyl phosphoric acid and octyl hydroxamic acid perform well in flotation tests of zircon. This technical note proposed a new approach to screen flotation reagents based on fast and accurate batch quantum chemistry calculations. Accordingly, the ethyl-functional group (EFG) data bank was used to calculate the reaction-free energy of solidophilic groups with possible metal hydroxide ions (the representatives of mineral surface sites). Then the obtained solidophilic groups possessing the best binding affinity with surface sites were linked with the C8 hydrocarbon chain to form the collectors [ n -octyl phosphoric acid (nOPA), octyl hydroxamic acid (OHA)]. The flotation results showed that the nOPA and OHA had much better flotation performance than the octanoic acid. These results showed that the quantum chemistry-assisted rational screening and design of flotation reagents was accurate and feasible. This work can shed new light on screening new and novel flotation reagents with virtual screening techniques. [ABSTRACT FROM AUTHOR]

Soil desiccation occurs widely across China's Loess Plateau due to long-term water demand in excess of water supply. Hydraulic redistribution (HR) - the movement of water from wet to dry soil via roots - and canopy dew (CD) are crucial to water replenishment in dryland ecosystems. However, much is still not known about the response of CD and HR to soil water deficits (including no deficit, slight deficit, moderate deficit, and severe deficit water conditions) in dryland jujube (Ziziphus jujuba Mill.) plantations in China's Hilly Loess Region. To this end, the duration and intensity of dew were monitored using dielectric leaf wetness sensors to better understand the effects of soil water status on dew. Also, soil water content, sap flow, and meteorological variables were measured during the jujube growing seasons in 2017–2019. The results showed that the time of occurrence of CD under the no deficit condition came earlier than the time of occurrence of CD under slight, moderate, and severe soil water deficit conditions. Peak CD appeared at 5:00–6:30 am and ended at 6:30–9:00 am local time under the four soil water conditions. The amount, duration, and frequency of CD decreased with increasing soil water deficit. The amount and duration of CD under the no deficit condition were significantly higher than under the slight, moderate, and severe soil water deficit conditions (p < 0.05). The amount and frequency of HR (in the 20–60 cm soil layer) increased with increasing soil water deficit. Under the no deficit condition, HR was significantly lower than under the slight, moderate, and severe soil water deficit conditions (p < 0.05). While HR was influenced by CD, CD enhanced HR under the no deficit condition, but inhibited HR under slight, moderate, and severe soil water deficit conditions. For the growing season, the contribution of CD to total actual evapotranspiration (ET c act , CD/ ET c act ratio) was highest under the no deficit condition (maximum CD/ ET c act ratio of 0.21). The contribution of HR to ET c act (HR/ ET c act ratio) was higher under slight, moderate, and severe soil water deficit conditions (maximum of 0.11). The mutual effects of CD and HR lessened soil water deficit, making them important ecohydrological processes affecting the response of dryland jujube plantations to soil desiccation. ● The amount and duration of canopy dew decreased with increasing soil water deficit. ● The hydraulic redistribution (HR) increased with increasing soil water deficit. ● HR was influenced by canopy dew. ● The mutual effect of canopy dew and HR lessened soil water deficit. [ABSTRACT FROM AUTHOR]

Activated nitrogen doped carbons (a-NCs) with microporous texture, tunable N doping level and forms were synthesized by carbonization and controllable alkali activation of polyaniline (PANI) precursor, which were further employed as electrode materials of supercapacitors and heterogeneous catalysts for 4-nitrophenol hydrogenation. Experimental results show that the activation temperature plays a crucial role on the specific surface area, N doping level and forms, graphitization degree and therefore the capacitive performance and catalytic activity of the afforded a-NCs, thus allow us to facilely tune the application performances as required. By activation at lower temperature (600 °C), the afforded a-NC 600 maintains high N and O contents, high fraction of pseudocapacitance active species as well as considerable surface area, all of which result in the maximized specific capacitance (309 F g −1 at current density of 1 A g −1 in acidic electrolyte). In contrast, the sample activated at 800 °C, labeled as a-NC 800 , demonstrates high surface area and increased graphitic N, thus can offer preferential heterogeneous catalytic activity for 4-nitrophenol hydrogenation reaction. [ABSTRACT FROM AUTHOR]

Nitrogen doped graphenes (NGs) were synthesized by pyrolysis of graphene polypyrrole composites (G-PPys) for application as counter electrode (CE) in dye sensitized solar cells (DSSCs). The as-prepared NGs demonstrate mesoporous texture with large specific surface areas, high N doping level with homogeneous distribution, as well as moderate graphitization phase, all of these structural and interfacial features are beneficial for abundant active sites and well conductivity, therefore can effectively promote the electrocatalytic reduction of I 3 − and improve the photovoltaic performances of pertinent DSSCs. The optimized sample, denoted as NG2, used as CE of DSSC exhibit high power conversion efficiency (PCE) (6.8%) with high reliability and durability, which is comparable to that of Pt CE (7.0%). Given the cost effective synthesis and the high electrochemical performance, NG2 herein is a promising non-Pt CE alternative material in DSSC. [ABSTRACT FROM AUTHOR]

In many technological applications, materials are transported by fluid flow at micro/nanometer scales. Conventionally, macroscopic apparatuses, such as syringe pumps, are used to drive the flow. This work explores the possibility of utilizing motile bacteria as microscopic pumps. We used micro-fabricated structures to confine smooth-swimming bacteria in a prescribed configuration. The flagella of confined bacteria rotate to collectively generate flow that can transport materials along designed trajectories. Different structures are combined to realize complex functions, such as collection or dispersion of particles. Experimental findings are reproduced in numerical simulations. Our method opens new ways to generate transport flow at the micrometer scale and to drive bio-hybrid devices. [ABSTRACT FROM AUTHOR]

In this work, the adsorption behavior of dodecylamine (DDA) on scheelite and calcite mineral surfaces were investigated by molecular dynamics (MD) simulation, zeta potential measurement, AFM observation, contact angle measurement, and flotation test. The results implied that, the different adsorption behavior of DDA on scheelite and calcite surfaces was mainly attributed to cationic species RNH 3 + of DDA. The adsorption of neutral species RNH 2 and complex precipitates produced by the reactions between RNH 3 + and anionic species released by both mineral surfaces, also played important roles. In a DDA solution (1 × 10 −4 mol/L, pH 7.5–8.0), a handful of RNH 2 of DDA adsorbed on both scheelite and calcite surfaces through N–Ca bonding and hydrogen bonding between hydrogens of –NH 2 group and mineral surface oxygens. On positively charged calcite surface, RNH 3 + adsorbed on a moderate number of CO 3 2 − sites through electrostatic attraction and hydrogen bonding, which caused a moderate zeta potential increase for calcite. On negatively charged scheelite surface, a large number of cationic species RNH 3 + could easily adsorb on abundant WO 4 2 − sites, which caused a significant increase of zeta potential for scheelite. The different adsorption behavior led to a heavier monolayer coverage of DDA species on scheelite surface, and thus a more hydrophobic surface and a better flotation recovery of scheelite. The present work helps propose a new adsorption model of DDA on scheelite and calcite. [ABSTRACT FROM AUTHOR]

The primary coexisting mineral with galena is sphalerite. Hence, it is critical to selectively separate galena from sphalerite by flotation. In this work, thiourea and related derivatives as potential flotation collectors for separating galena from sphalerite were investigated. Thiourea and its related derivatives were found to be effective selective collectors in batch flotation studies of a single mineral, with 1,1-diphenylthiourea (11DTA) emerging as the best choice. Galena has superior floatability compared to sphalerite in the presence of 11DTA, and the recovery difference between the two minerals at pH 8 (where the 11DTA concentration is 5 × 10−6 mol/L) is around 38%. This was revealed in batch flotation studies using artificial mixed minerals. Moreover, the findings from the measurements of adsorption amount, FTIR, zeta potential and XPS revealed that 11DTA has a strong adsorption on galena yet a relatively weak adsorption on sphalerite. Additionally, DFT calculations demonstrated that sphalerite exhibits stronger hydrophilicity than galena, and 11DTA possessed a better affinity for galena. [ABSTRACT FROM AUTHOR]

Tin and its compounds have a variety of applications. It is recovered as cassiterite from ore deposit by flotation. Traditionally, the use of fatty acids and their derivatives with limited selectivity of cassiterite over calcite (the main gangue mineral) has been replaced by benzohydroxamic acid (BHA). BHA shows poor collecting ability to cassiterite, even when lead nitrate (LN) is added as the activator. In this work, the flotation results show that cassiterite can be separated efficiently from cassiterite-calcite binary mixed minerals using a mixture of LN/BHA as collector and carboxymethyl cellulose (CMC) as depressant. The separation performance of the mixture of LN/BHA is much better compared with adding LN and BHA in sequence at the same dosage. Zeta potential measurements indicate that the mixture of LN/BHA exhibits much stronger ability to adsorb on cassiterite compared with adding LN and BHA in sequence even in the presence of CMC. [ABSTRACT FROM AUTHOR]

Humans can easily understand other people’s actions through visual systems, while computers cannot. Therefore, a new bio-inspired computational model is proposed in this paper aiming for automatic action recognition. The model focuses on dynamic properties of neurons and neural networks in the primary visual cortex (V1), and simulates the procedure of information processing in V1, which consists of visual perception, visual attention and representation of human action. In our model, a family of the three-dimensional spatial-temporal correlative Gabor filters is used to model the dynamic properties of the classical receptive field of V1 simple cell tuned to different speeds and orientations in time for detection of spatiotemporal information from video sequences. Based on the inhibitory effect of stimuli outside the classical receptive field caused by lateral connections of spiking neuron networks in V1, we propose surround suppressive operator to further process spatiotemporal information. Visual attention model based on perceptual grouping is integrated into our model to filter and group different regions. Moreover, in order to represent the human action, we consider the characteristic of the neural code: mean motion map based on analysis of spike trains generated by spiking neurons. The experimental evaluation on some publicly available action datasets and comparison with the state-of-the-art approaches demonstrate the superior performance of the proposed model. [ABSTRACT FROM AUTHOR]

Collector 733, a sodium soap (C 12 – 16 COONa) is widely used industrially for scheelite flotation. Low selectivity of 733 collector is always observed. In this study, a collector mixture of 733 and MES (sodium fatty acid methyl ester sulfonate) demonstrated a high selectivity for the flotation of scheelite from calcite and fluorite. An optimal mass ratio 4:1 of 733:MES was found, producing a 65.76% WO 3 concentrate grade with a recovery of 66.04% from a feed material containing only 0.57% WO 3 . In addition, the effect of water hardness and water glass addition were studied. The results indicated that the presence of Ca 2+ or Mg 2+ had little effect on the adsorption of the collector mixture at the scheelite surface. Addition of water glass for depressing calcite and fluorite had no significant effect on the adsorption of the collector mixture on the scheelite surface. The advantages of this new collector mixture (733+MES) include lower cost, low dosage, high tolerance against water hardness and high selectivity, and this collector mixture has great potential for industrial application. [ABSTRACT FROM AUTHOR]

Activated porous carbons containing both micropores and meso-/macropores are prepared by cost-effective pyrolysis carbonization and the subsequent alkali activation of a easily available biomass, paulownia flower (PF). The as-prepared activated PF carbons (a-PFCs) show high specific surface areas, suitable pore size distributions, superhydrophilicity and partial graphitization phase, all of which are essential for achieving high electrochemical performances as supercapacitor electrodes. The symmetric supercapacitor based on a-PFC 3 , which is synthesized at the mass ratio of KOH to PF derived carbon (PFC) to be 3 during activation step, offers a specific capacitance of 297 F g −1 at current density of 1 A g −1 within potential range of #2–3#1 V using 1 M H 2 SO 4 electrolyte. Owing to the high specific capacitance and wide potential window, the supercapacitor delivers high energy densities of 44.5∼22.2 Wh kg −1 under the power outputs of 247∼3781 W kg −1 . The high specific capacitance, good rate capability, superior cycling reliability and excellent capacitance maintaining ability in tandem cell group make the a-PFC 3 supercapacitor a competitive unit in assembling of amplified tandem battery pack. [ABSTRACT FROM AUTHOR]

Segmentation of the left ventricle is very important to quantitatively analyze global and regional cardiac function from magnetic resonance. The aim of this study is to develop a novel algorithm for segmenting left ventricle on short-axis cardiac magnetic resonance images (MRI) to improve the performance of computer-aided diagnosis (CAD) systems. In this research, an automatic segmentation method for left ventricle is proposed on the basis of local binary fitting (LBF) model and dynamic programming techniques. The validation experiments are performed on a pool of data sets of 45 cases. For both endo- and epi-cardial contours of our results, percentage of good contours is about 93.5%, the average perpendicular distance are about 2 mm. The overlapping dice metric is about 0.91. The regression and determination coefficient between the experts and our proposed method on the LV mass is 1.038 and 0.9033, respectively; they are 1.076 and 0.9386 for ejection fraction (EF). The proposed segmentation method shows the better performance and has great potential in improving the accuracy of computer-aided diagnosis systems in cardiovascular diseases. [ABSTRACT FROM AUTHOR]

In liquid-solid fluidized beds, the existence of the interstitial liquid among particles generates more energy dissipation different from that for gas-solid flows. To accurately predict the flow behavior of particles in a liquid-solid fluidization system, we simulate liquid-solid fluidization by introducing a dynamic coefficient of restitution model into the kinetic theory of granular flow. The dynamic coefficient of restitution is obtained by incorporating a semi-empirical correlation generated from a freely falling particle impacting a wet plate with a critical Stokes number, and the variable critical Stokes number is used to judge whether particles rebound after the collision. Simulated results show that the granular temperature and granular pressure are clearly affected when the dynamic coefficient of restitution model is introduced. As well, the particles velocity distribution predicted by the dynamic coefficient of restitution model is in better agreement with the experimental values compared with the constant coefficient of restitution. [Display omitted] • A dynamic COR combining the semi-empirical correlation with the critical St is proposed. • The critical St is a variable related to the impact velocity and particles properties. • The impact velocity of particles is expressed as a function of granular temperature. • The dynamic COR combined with TFM can predict solid holdup distribution as accurate as DEM. [ABSTRACT FROM AUTHOR]

In this study, flotation behavior of scheelite and calcite was investigated using mixed cationic/anionic collectors of dodecylamine (DDA) and sodium oleate (NaOL). Individual NaOL or DDA was also tested for comparison. The flotation results of single mineral and mixed binary minerals demonstrated a high selectivity and recovery for the flotation of scheelite from calcite at pH 7 using mixed DDA/NaOL collectors. The adsorption mechanism of the selective separation was analyzed through zeta potential measurement. [ABSTRACT FROM AUTHOR]

Abstract: Chemically grafted p-aniline-functionalized graphene-polyaniline composite (a-G-PANI) is synthesized by covalent bonding and polymerization of aniline onto p-aniline functionalized graphene (a-G) substrate. To achieve this purpose, a-G substrate is initially synthesized via an easily-processible and powerful p-phenylenediamine diazotisation reaction, the modified p-aniline groups further serve as initiation sites for the chemical grafting and polymerization of aniline. The as-prepared a-G-PANI exhibits planar configuration with rich pores, which is formed by the conjugated bonding and coating of PANI nanofibers onto graphene sheet, endowing the composite with essential merits including high conductivity, efficient electrolyte diffusion channel and exposure of highly pseudocapacitive PANI to electrolyte, hence, a combined electric double-layer (EDL) capacitance and pseudocapacitance property is achieved. Supercapacitor based on a-G-PANI200 composite with a-G to PANI ratio of 1:200 demonstrates high electrochemical capacitance (422 F g−1) at discharge rate of 1Ag−1, which is dramatically higher than that based on sole a-G or PANI. The rate performance and cycling stability of a-G-PANI200 based supercapacitor are also enhanced relative to sole PANI based counterpart, highlighting the structural advantage of chemically grafted a-G-PANI for capacitor applications. [Copyright &y& Elsevier]

Highlights: [•] AsT was successfully synthesized through conjugation with TGN, AS1411 and Cy3. [•] AsT could effectively target to glioma with high intensity. [•] AsT could be used as an effective glioma imaging probe. [Copyright &y& Elsevier]

The autonomous Mutator ( Mu) transposon in maize ( Zea mays L.) lines 115F, 330I, and 715D were crossed with inbred lines B73, Mo17, 97108, and H9-21, M were self-pollinated to establish the Mu insertion-mutagenized M seeds pool and The M plants encompassed a large amount of biological variation relevant to improving agronomy traits by observed in the field. Next we statistically analyzed these candidate mutants. Under drought stress, we screened seedlings at 3-leaf stage by using the infrared thermography, and successfully got 108 drought-insensitive and 121 drought-sensitive candidate mutants from more than 38,000 lines, which temperature were significant different with others. These candidate mutants were primarily analyzed by infrared thermography, chlorophyll fluorescence, leaf water losing, photosynthetic characteristics, content of soluble sugars, soluble protein, and proline assay. The selected mutants were cloned by MuTAIL-PCR methods. Here we provide the better genetic materials for research on maize breeding for drought tolerance. [ABSTRACT FROM AUTHOR]

Highlights: [•] CoS2–graphene composite was facilely synthesized. [•] CoS2–graphene showed high catalytic activity and efficient electrolyte diffusion path. [•] CoS2–graphene counter electrode offered enhanced photovoltaic efficiency. [Copyright &y& Elsevier]

Highlights: [•] Site preference and phase stability of NiMnGaTi are studied by first-principles. [•] The Ti atoms prefer to occupy the Ga sites in the Ni2MnGa austenitic phase. [•] The phase stability becomes worse when Ga is replaced by Ti. [•] The phase stability is discussed based on the densities of states. [Copyright &y& Elsevier]