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Using a simple dipping method, a novel the magnetically driven hydrophobic polyurethane sponge (MHPS) was synthesized in this work. The isodecyl alcohol with longer carbon chain is grafted onto the sponge surface through substitution reaction and condensation reaction, and Fe3O4 nanoparticles are adhered to the sponge to give it magnetism and make it easy to collect. MHPS were characterized by Fourier transformed infrared, X-ray diffraction, scanning electron microscopy and energy dispersive spectrometers. The maximum adsorption capacity for various oils/organic solvents was 24–50 times its own weight. MHPS shows excellent reusability after ten absorption–extrusion-heating cycles. Moreover, it can selectively absorb and continuously remove oil in a wide range of water due to the combination of its high porosity, hydrophobicity and lipophilicity. The magnetism of MHPS makes it easy to collect with magnets. It is believed that MHPS has potential application prospects in oil purification and oil spill removal industry wastewater.

Sparrow search algorithm (SSA) is easy to fall into local convergence and convergence stagnation. In order to solve these problems, this paper introduced Circle chaos map into the original SSA to improve its global search ability at the beginning of iteration. Meanwhile, it introduced T-distribution variation to affect the sparrow population position update rules in different iteration periods. Finally, we constructed the “similarity function” to measure the “dispersion” of the sparrow population, and formulated the search rules of the sparrow population under different “dispersion”. In order to test the specific optimization performance of the proposed algorithm, the test results of 54 test functions are compared with those of 9 other algorithms which are widely used, and then the test results are analyzed using non-parametric tests in statistics. At the same time, this paper introduces this algorithm into three concrete engineering test problems for testing. The results of these tests all prove that the proposed algorithm has stronger global optimization ability and higher convergence precision compared with other algorithms.

Steric hindrance of methyl on reaction pathway of hydrodesulfurization in presence of quinoline was investigated over a NiMo/Al2O3 catalyst at 4.0 MPa and 320 °C. The results show that steric hindrance of methyl changed the main pathway of HDS while presence of quinoline further exacerbated this transformation. Changes in inhibitory factor curve show that quinoline poisoning on DBT HDS is a relatively mild. When adjacent methyl is present, even at low concentration, the inhibitory factor of quinoline on 4,6-DMDBT HDS is still greater than 85%. At high levels, the inhibitory factor of quinoline on DDS pathway even exceeds 99%. Quinoline poisons HYD pathway of DBT HDS to a stable level in a short time (30 to 60 min). However, after 6 h of reaction, HYD pathway yield of 4,6-DMDBT HDS is still increasing. Quinoline simultaneously poisons HYD and DDS pathways of 4,6-DMDBT HDS to a stable level within 120 min, and then DDS pathway will continue to be poisoned, thereby increasing HYD pathway yield. Regardless of presence of adjacent methyl in sulfur-containing molecules, an increase in quinoline concentration will lead to an increase in HYD/DDS pathway yield ratio. Addition of quinoline inhibits conversion of hydrogenated intermediates to DDS products by poisoning C–S bond dissociation center (such as CUS active site) and leads to formation of deep hydrogenated products.

UV Raman, TG-MS (TPO) and nitrogen physisorption characterization were used to characterize deactivated Mo/HZSM-5 catalysts from coupling reaction of methane CO2 autothermal reforming (MCAR) and methane dehydroaromatization (MDA). The results show that MCAR/MDA maintains the Mo-oxo species throughout the process, reducing the maximum C6H6 yield, but extending the reaction life by at least 4 time. As O/CH4 increases, MCAR/MDA changes from oxygen-deficient to oxygen-rich state. For MCAR/MDA under oxygen-deficient condition, O2 can only delay the accumulation of aromatics. Grown of coke on Brӧnsted acid eventually leads to complete blockage of the micropores of the catalyst. Slowly deposited graphite coke in MCAR/MDA extended the critical time by nearly 4 times. For MCAR/MDA under oxygen-rich condition, a 70% C6H6 selectivity was maintained throughout the process. After 3700 min of operation, the remaining micropore volume and micropore surface of the deactivated catalyst remained above 1/3. The timely removal of graphite coke at the pore mouth by the MCAR/MDA reaction under oxygen-rich conditions can eliminate the limitation of C6H6 diffusion, thereby effectively preventing the acceleration of the coke deposit micropores which cause the MDA reaction to be rapidly deactivated.

The tree of life (TOL) is severely threatened by climate and land-cover changes. Preserving the TOL is urgent, but has not been included in the post-2020 global biodiversity framework. Protected areas (PAs) are fundamental for biological conservation. However, we know little about the effectiveness of existing PAs in preserving the TOL of plants and how to prioritize PA expansion for better TOL preservation under future climate and land-cover changes. Here, using high-resolution distribution maps of 8732 woody species in China and phylogeny-based Zonation, we find that current PAs perform poorly in preserving the TOL both at the present and in 2070s. The geographical coverage of TOL branches by current PAs is ca 9%, and less than 3% of the identified priority areas for preserving the TOL are currently protected. Interestingly, the geographical coverage of TOL branches by PAs will be improved from 9 to 52–79% by the identified priority areas for PA expansion. Human pressures in the identified priority areas are high, leading to high cost for future PA expansion. We thus suggest that besides nature reserves and national parks, other effective area-based conservation measures should be considered. Our study argues for the inclusion of preserving the TOL in the post-2020 conservation framework, and provides references for decision-makers to preserve the Earth's evolutionary history.

The tree of life (TOL) is severely threatened by climate and land-cover changes. Preserving the TOL is urgent, but has not been included in the post-2020 global biodiversity framework. Protected areas (PAs) are fundamental for biological conservation. However, we know little about the effectiveness of existing PAs in preserving the TOL of plants and how to prioritize PA expansion for better TOL preservation under future climate and land-cover changes. Here, using high-resolution distribution maps of 8732 woody species in China and phylogeny-based Zonation, we find that current PAs perform poorly in preserving the TOL both at the present and in 2070s. The geographical coverage of TOL branches by current PAs is ca 9%, and less than 3% of the identified priority areas for preserving the TOL are currently protected. Interestingly, the geographical coverage of TOL branches by PAs will be improved from 9 to 52–79% by the identified priority areas for PA expansion. Human pressures in the identified priority areas are high, leading to high cost for future PA expansion. We thus suggest that besides nature reserves and national parks, other effective area-based conservation measures should be considered. Our study argues for the inclusion of preserving the TOL in the post-2020 conservation framework, and provides references for decision-makers to preserve the Earth's evolutionary history.

The tree of life (TOL) is severely threatened by climate and land-cover changes. Preserving the TOL is urgent, but has not been included in the post-2020 global biodiversity framework. Protected areas (PAs) are fundamental for biological conservation. However, we know little about the effectiveness of existing PAs in preserving the TOL of plants and how to prioritize PA expansion for better TOL preservation under future climate and land-cover changes. Here, using high-resolution distribution maps of 8732 woody species in China and phylogeny-based Zonation, we find that current PAs perform poorly in preserving the TOL both at the present and in 2070s. The geographical coverage of TOL branches by current PAs is ca 9%, and less than 3% of the identified priority areas for preserving the TOL are currently protected. Interestingly, the geographical coverage of TOL branches by PAs will be improved from 9 to 52–79% by the identified priority areas for PA expansion. Human pressures in the identified priority areas are high, leading to high cost for future PA expansion. We thus suggest that besides nature reserves and national parks, other effective area-based conservation measures should be considered. Our study argues for the inclusion of preserving the TOL in the post-2020 conservation framework, and provides references for decision-makers to preserve the Earth's evolutionary history.

The tree of life (TOL) is severely threatened by climate and land-cover changes. Preserving the TOL is urgent, but has not been included in the post-2020 global biodiversity framework. Protected areas (PAs) are fundamental for biological conservation. However, we know little about the effectiveness of existing PAs in preserving the TOL of plants and how to prioritize PA expansion for better TOL preservation under future climate and land-cover changes. Here, using high-resolution distribution maps of 8732 woody species in China and phylogeny-based Zonation, we find that current PAs perform poorly in preserving the TOL both at the present and in 2070s. The geographical coverage of TOL branches by current PAs is ca 9%, and less than 3% of the identified priority areas for preserving the TOL are currently protected. Interestingly, the geographical coverage of TOL branches by PAs will be improved from 9 to 52–79% by the identified priority areas for PA expansion. Human pressures in the identified priority areas are high, leading to high cost for future PA expansion. We thus suggest that besides nature reserves and national parks, other effective area-based conservation measures should be considered. Our study argues for the inclusion of preserving the TOL in the post-2020 conservation framework, and provides references for decision-makers to preserve the Earth's evolutionary history.

The documentation of biodiversity distribution through species range identification is crucial for macroecology, biogeography, conservation, and restoration. However, for plants, species range maps remain scarce and often inaccurate. We present a novel approach to map species ranges at a global scale, integrating polygon mapping and species distribution modelling (SDM). We develop a polygon mapping algorithm by considering distances and nestedness of occurrences. We further apply an SDM approach considering multiple modelling algorithms, complexity levels, and pseudo-absence selections to map the species at a high spatial resolution and intersect it with the generated polygons. We use this approach to construct range maps for all 1957 species of Fagales and Pinales with data compilated from multiple sources. We construct high-resolution global species richness maps of these important plant clades, and document diversity hotspots for both clades in southern and south-western China, Central America, and Borneo. We validate the approach with two representative genera, Quercus and Pinus, using previously published coarser range maps, and find good agreement. By efficiently producing high-resolution range maps, our mapping approach offers a new tool in the field of macroecology for studying global species distribution patterns and supporting ongoing conservation efforts., Entomologia Experimentalis et Applicata, 170 (6), ISSN:0013-8703, ISSN:1570-7458

A brand-new environmental-friendly magnetic cellulosic adsorbent MnFe2O4@Cel-g-p(AA-DMC) was synthesized by natural cellulose and easy-recovered magnetic particles MnFe2O4. Magnetic cellulose composites were characterized by SEM, TEM, XPS, XRD, BET, VSM, TGA and FTIR. The MnFe2O4NPs could activate the peroxymonosulfate (PMS) to produce various reactive oxygen species (ROS). Accordingly, magnetic cellulose composites can synergistic adsorption degradation of dyes from organic wastewater. The Congo red (CR) removal efficiency by MnFe2O4@Cel-g-p(AA-DMC) via PMS activated by MnFe2O4 reached a maximum of 96.9% and only 9% reduction after four adsorption-desorption cycles, indicating the stability and recoverability of adsorbent. It is worth noting that adsorbents can be quickly recovered from aqueous solution by external magnet owing to superior saturation magnetization (35.44 emu·g-1). A possible degradation mechanism of CR on the MnFe2O4@Cel-g-p(AA-DMC) composite was proposed. The results suggest that adsorbent display strong potential for the removal of CR dyes from organic wastewater.

The rapid progress of photorealistic synthesis techniques has reached a critical point where the boundary between real and manipulated images starts to blur. Recently, a mega-scale deep face forgery dataset, ForgeryNet which comprised of 2.9 million images and 221,247 videos has been released. It is by far the largest publicly available in terms of data-scale, manipulations (7 image-level approaches, 8 video-level approaches), perturbations (36 independent and more mixed perturbations), and annotations (6.3 million classification labels, 2.9 million manipulated area annotations, and 221,247 temporal forgery segment labels). This paper reports methods and results in the ForgeryNet - Face Forgery Analysis Challenge 2021, which employs the ForgeryNet benchmark. The model evaluation is conducted offline on the private test set. A total of 186 participants registered for the competition, and 11 teams made valid submissions. We will analyze the top-ranked solutions and present some discussion on future work directions., Comment: Technical report. Challenge website: https://competitions.codalab.org/competitions/33386

The 3-replica redundancy strategy is widely used to solve the problem of data reliability in large-scale distributed storage systems. However, its storage capacity utilization is only 33%. In this paper, a data placement algorithm based on fault-tolerant domain (FTD) is proposed. Owing to the fine-grained design of the FTD, the data reliability of systems using two replicas is comparable to that of current mainstream systems using three replicas, and the capacity utilization is increased to 50%. Moreover, the proposed FTD provides a new concept for the design of distributed storage systems. Distributed storage systems can take FTDs as the units for data placement, data migration, data repair and so on. In addition, fault detection can be performed independently and concurrently within the FTDs.

The evolution of the energy difference between the neutron states $1i_{13/2}$ and $1h_{9/2}$ in the $N=82$ isotones and that between the proton states $1h_{11/2}$ and $1g_{7/2}$ in the $Z = 50$ isotopes are investigated within the framework of the relativistic Hartree-Fock theory, using the density-dependent effective interactions PKA1 and PKO$i$ ($i = 1 $, $ 2 $, $ 3 $). By identifying the contributions of the tensor force, which is naturally induced via the Fock terms, we find that the tensor force plays crucial roles in the evolution of the shell structure. The strength of the tensor force is also explored. It is found that moderately increasing the coupling strength of pion-nucleon coupling, i.e., $f_{\pi}$, will significantly improve the description of the shell-structure evolution. In particular, reducing the density dependence of $f_{\pi}$ is shown to be more preferable, in comparison to enlarging $f_{\pi}$ with a factor. This is in consistence with the idea of "tensor renormalization persistency" and provides valuable guidance for the development of nuclear energy density functional in the relativistic framework., Comment: 15 pages, 7 figures, 3 tables

An experimental study on the bond behavior of steel bar in air-entrained recycled coarse aggregate concrete (RCAC) in fresh water and sea water under the action of fast freeze-thaw (F-T) cycles was carried out. A total of 63 center pull-out specimens, including 9 unfreezed specimens and 54 freezed specimens which suffered from 25, 50 or 75 cycles of fast F-T according to standard GB/T 50082-2009, were constructed and tested to investigate the effect of the following parameters: (a) number of fast F-T cycles, (b) solution, (c) diameter of steel bar on the bond behavior of steel bar in air-entrained RCAC. The experimental results were compared with bond behavior of steel bar in RCAC conducted by the author. By comparison, the bond behavior is found to be improved greatly through mixed air-entraining agent into RCAC. A calculation expression of bond strength of steel bar in air-entrained RCAC considering number of fast F-T cycles is proposed based on the experimental results obtained in this paper.

Using chemical co-precipitation method to make a magnetic magnetite, dithiocarbamate-multifunctional embedded in the carboxyl group to synthesize a novel nanocomposite Fe3O4@SiO2-DTPA-DTC for adsorption the Co2+ from aqueous solution. The Fe3O4@SiO2-DTPA-DTC composites were characterized by XRD, SEM, TEM, FT-IR, XPS, TGA and VSM in this study. From the adsorption study, removal efficiency of Co2+ on Fe3O4@SiO2-DTPA-DTC is up to 98%. The adsorption reached equilibrium within 5 min. The optimum pH was recorded to be 6.0. The adsorption process fitted with Freundlich isotherm model and adsorption mechanism is chemical adsorption. After five-cycle adsorption test, the nanocomposites maintain high removal efficiency. The results showed that the Fe3O4@SiO2-DTPA-DTC can be considered as a promising adsorbent to adsorption the Co2+ from aqueous solution.

This study presents a novel texture descriptor for curve matching, called ternary contextualised histogram pattern (TCHP), which is based on the intensity order histogram and local ternary homogeneity patterns. Local ternary homogeneity patterns are firstly adopted to represent the texture features of the curve's neighbourhood, which ensures the robustness and distinctiveness of the descriptor. The proposed TCHP is constructed by three steps: firstly, the curve support region without assigning a dominant orientation is determined and then partitioned into several ordinal bins according to the intensity permutation; then, ternary contextualised histogram (TCH) feature of each point is generated by computing the statistics of the predefined ternary homogeneity patterns; finally, TCHP is achieved by accumulating the TCHs of points in each order bin. Experiments show TCHP can effectively characterise the texture features of the curve's neighbourhood and performs robust to image rotation, viewpoint change and illumination change.

A gesture recognition based Human-Computer Interaction control system is developed via LabVIEW in this paper. Furthermore, to solve the existing problems of lower precision and poor real-time ability in gesture recognition algorithm, an improved PSO-SVM classification algorithm of hand-gesture recognition is proposed. Firstly, the gesture sample data is collected by using five bending sensor of data glove, then, in order to improve the recognized precision, the data collected is preprocessed and the optimize the SVM kernel parameter value is found by using the improved PSO algorithm. Finally, the recognized hand-gesture is divided into numbered 1–11 control status values, and sent to the sample robot controller by wireless transmission module and achieving the realization of sampling robot motion control. The simulation results illustrate the effectiveness of designed method on

This paper performs a comprehensive and comparative evaluation of the state of the art local features for the task of image based 3D reconstruction. The evaluated local features cover the recently developed ones by using powerful machine learning techniques and the elaborately designed handcrafted features. To obtain a comprehensive evaluation, we choose to include both float type features and binary ones. Meanwhile, two kinds of datasets have been used in this evaluation. One is a dataset of many different scene types with groundtruth 3D points, containing images of different scenes captured at fixed positions, for quantitative performance evaluation of different local features in the controlled image capturing situations. The other dataset contains Internet scale image sets of several landmarks with a lot of unrelated images, which is used for qualitative performance evaluation of different local features in the free image collection situations. Our experimental results show that binary features are competent to reconstruct scenes from controlled image sequences with only a fraction of processing time compared to use float type features. However, for the case of large scale image set with many distracting images, float type features show a clear advantage over binary ones.

The inductance gradient is one of the most important indexes to evaluate the performance of the electromagnetic railgun. It has important theoretical and practical value to research the inductance gradient and its influencing parameters. According to the Biot-Savat's law and the principle of virtual work, the expression of the inductance gradient considered the skin effect of current has been given, and by using Monte-Carlo algorithm the numerical solution has been calculated. In order to verify the correctness and accuracy of the model, the finite element simulation software is used to compare with the numerical solution. Based on the model, the influencing parameters of inductance gradient has been analyzed, and the variation of the inductance gradient has been summarized. The results show that, the inductance gradient decrease with the separation distance between the inside and outside rail, decrease with the height and width of the rail, increase with the displacement of the armature then tend to constant. The research can provide a reference for the design of series-connected augmented railgun.

A new type of air-driven multi-fingered dexterous hand, named ZJUT Hand, is proposed. ZJUT Hand has good passive flexibility and can make up for the deficiency of existing dexterous hands in some ways. A new method for grasping model identification based ANFIS is proposed. Simulation experimental results show that the method can easily establish the model of the target objects, and has very good recognition accuracy and convergence. Equivalent rules of target objects are presented and greatly improve the efficiency of identification. A general grasp planning program of multi-fingered dexterous hand is proposed. Finally, the grasp planning experiments for ZJUT Hand is completed. Experimental results show that ZJUT Hand is able to construct the models of two typical target objects.

This paper deals with the analysis of deformation tendencies in the drawing of plate with a hole and offers a corresponding technological procedure as well as the equations for quantitative calculation. Also, a computer block-diagram is provided that is consistent with various lubrication conditions used in production. By means of running the software concerned and from the results of experimental research, it is established that the technological procedure and the equations presented in this paper can solve various problems in the drawing of a plate with a hole, both in production and in the procedures of product design. The software is suitable for all materials used for drawing.

This paper deals with the analysis of deformation tendencies on drawing plate with hole and offers a corresponding technological procedure as well as the quantitative calculation formulas. Also, a computer block diagram has been provided in accordance with various lubrication conditions in production. Through running the software concerned and experimental research, it is proved that the technological procedure and formulas presented in this paper may solve various problems for drawing the plate with hole both in production and in products design procedure. This software is suitable for any drawing materials.

This paper deals with the theoretical analysis of the deformation tendency in the drawing of a sheet with a hole in a combined forming process. A mathematical model for calculating the condition of no deformation of the hole in the drawing of a sheet with a hole has been obtained and experimental research has been undertaken. The results obtained in the paper may provide significant information for practical production. In the production of a drawn component with a bottom hole, where the accuracy of the latter has to be ensured, the most common method is to form a recessed part first, then punch the hole. To date, the authors cannot find any papers that indicate definitely whether the diameter of the hole may influence the deformation of the workpiece and thus change its own value. Obviously, if the hole diameter is unchanged during drawing, the hole may be punched before drawing: it is much easier to punch a hole on a sheet blank than on a recessed part. Moreover, the existence of the hole makes it more convenient to position the blank. Hence, it is absolutely significant to study quantitatively the deformation tendency of the hole during drawing.

The basic problem of obtaining contrast reversal by pi-phase filtering of an image is discussed, and the condition for obtaining contrast reversal is deduced. Computer-simulation results are presented. These-show that, in general, within a certain density range pi-phase filtering produces contrast reversal, that this reversal is strongly dependent on the width of the filter, and that this filtering will cause deformation of density in pseudocolor encoding. The effect of the width of the filter and the density distribution of the image on encoding deformation and the density range of contrast reversal is demonstrated.

For the shortcomings of existing dexterous hands,such as structure complexity and control difficulty,a new type of pneumatic multi-fingered dexterous hand,named ZJUT Hand,is proposed.Based on a flexible pneumatic actuator (FPA),pneumatic stiffness/compliance bending joint and side-sway joint are designed.After that,a 4-DOF pneumatic anthropomorphic finger with four joints is assembled.To achieve a high degree of modularity,five identical fingers are installed on a anthropomorphic palm to constitute the body structure of ZJUT Hand with 20 DOFs.The structural parameters of ZJUT Hand are determined by the bionic optimization method,and grasping simulation experiments are carried out for body structure of ZJUT Hand.Simulation results show that:ZJUT Hand can grasp objects with typical shapes such as cylinder,strip and spherical objects,and achieve the pinching,gripping,pulling and other complex movements like human hand.The force/position sensory system for ZJUT Hand is developed.The grasp planning experiments for ZJUT Hand is completed.Experimental results show that ZJUT Hand is able to perform stable grasping for typical target objects.Finally, the characteristics of ZJUT Hand are summarized.

The documentation of biodiversity distribution through species range identification is crucial for macroecology, biogeography, conservation, and restoration. However, for plants, species range maps remain scarce and often inaccurate. We present a novel approach to map species ranges at a global scale, integrating polygon mapping and species distribution modelling (SDM). We develop a polygon mapping algorithm by considering distances and nestedness of occurrences. We further apply an SDM approach considering multiple modelling algorithms, complexity levels, and pseudo-absence selections to map the species at a high spatial resolution and intersect it with the generated polygons. We use this approach to construct range maps for all 1957 species of Fagales and Pinales with data compilated from multiple sources. We construct high-resolution global species richness maps of these important plant clades, and document diversity hotspots for both clades in southern and south-western China, Central America, and Borneo. We validate the approach with two representative genera, Quercus and Pinus, using previously published coarser range maps, and find good agreement. By efficiently producing high-resolution range maps, our mapping approach offers a new tool in the field of macroecology for studying global species distribution patterns and supporting ongoing conservation efforts., New Phytologist, 235 (2), ISSN:0028-646X, ISSN:1469-8137