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This paper presents a chaotic optimal thermodynamic evolutionary algorithm (COTEA) designed to address the integrated scheduling problems of berth allocation, ship unloader scheduling, and yard allocation at bulk cargo terminals. Our proposed COTEA introduces a thermal transition crossover method that effectively circumvents local optima in the scheduling solution process. Additionally, the method innovatively combines a good point set with chaotic dynamics within an integrated initialization framework, thereby cultivating a robust and exploratory initial population for the optimization algorithm. To further enhance the selection process, our paper proposes a refined parental selection protocol that employs a quantified hypervolume contribution metric to discern superior candidate solutions. Postevolution, our algorithm employs a Cauchy inverse cumulative distribution-based neighborhood search to effectively explore and enhance the solution spaces, significantly accelerating the convergence speed during the scheduling solution process. The proposed method is adept at achieving multiobjective optimization, simultaneously improving the service level and reducing costs for bulk cargo terminals, which in turn boosts their competitiveness. The effectiveness of our COTEA is demonstrated through extensive numerical simulations. [ABSTRACT FROM AUTHOR]

LiFePO4 has become a mainstream cathode material, owing to its good safety and low price. However, its intrinsic limitations in terms of electronic and ionic conductivities hinder its further advancements. To overcome this challenge, element doping has been explored to enhance its conductivity. Here, Na and F co-doped LiFePO4/C was successfully synthesized via a carbothermic method. Structural characterization techniques were employed to confirm the formation of Li0.97Na0.03FePO3.97F0.03 with controllable particle sizes. The incorporation of Na and F ions into the LiFePO4 lattice results in a reduction of the Li-O bond energy. This decrease in bond energy facilitates the extraction and insertion of lithium ions during the charge and discharge processes, subsequently improving the overall kinetics of lithium-ion diffusion. Simultaneously, lattice distortion induced by doping led to charge compensation and accelerated Li+ migration. Benefiting from the enhancement of intrinsic conductivity and Li+ diffusivity, the specific capacitance of the co-doped LiFePO4/C cathode material was found to be 160 and 110 mAh g−1 at 0.1 and 5 C, respectively. Further, density functional theory calculations showed that Na/F co-doping enhanced the structural evolution in the material and increased free carrier concentration in LiFePO4. This work demonstrates that synergistic Na and F co-doping can optimize the rate performance of LiFePO4 by enhancing intrinsic conductivity and Li+ diffusivity, suggesting promising applications of the co-doped LiFePO4/C in high-power lithium-ion batteries for electric vehicles and grid-level energy storage systems. [ABSTRACT FROM AUTHOR]

There have been ample three-dimensional (3D) wearable piezoresistive sensors with high sensitivity, fast response, and outstanding long-term stability. Nevertheless, less consideration is given to simple fabrication, economical materials, and comfort. Herein, a simple and cost-effective strategy for fabricating piezoresistive sensors is presented based on commercial 3D air-laid nonwovens (NW), poly(tetrafluoroethylene-co-hexafluoropropylene-co-vinylidene fluoride) (THV), and carbon nanotubes (CNTs) via one-step dip-coating method. CNTs without functionalization are dispersed homogenously in the solvent and coated uniformly on the substrate with the help of THV as dispersant and adhesive. This highly compressible 3D NW-THV-CNTs piezoresistive sensor showcases splendent air permeability (2682.33 mm·s−1), water–vapor permeability (1625.50 g·m−2·d−1) and super-hydrophobicity (water contact angle = 158.5°), and is characterized by remarkable photothermal performance. Furthermore, the NW-THV-CNTs sensor has a sensitivity of 1.26 kPa−1 with good linearity (r2 = 0.99833) in wide detecting range (0–100 kPa), moderate response time (0.45 s) and release time (0.25 s), and good cyclic stability. Additionally, the sensor excels in monitoring human activities, and the array sensor composed of 4 × 4 pixels is capable of plotting distribution and shape of pressure. [ABSTRACT FROM AUTHOR]

Extrusion molding is an important method in the polymer processing industry. The stress concentration of polymer melts can easily occur at the contraction channel, especially at the contraction exit during extrusion molding, which causes volume defects in the final parts. To eliminate or minimize volume defects, this study examined the effects of contraction profiles and contraction lengths on the rheological behaviors of polystyrene melts based on numerical methods and algorithms in the current study. The contraction profiles included abrupt contraction, V-shaped contraction, hyperbolic contraction, and elliptic contraction geometries at different contraction lengths. A single-mode Rolie-Poly model was employed to describe the stress–strain relationship of polystyrene melt. Additionally, the finite volume method and SIMPLE algorithm were used to discretize and solve the governing equations of the fluid in a 4:1 contraction flow. Numerical simulations of the principal stress difference (PSD), stretch ratio, and velocity of polystyrene melt in the aforementioned contraction geometries were implemented. The numerical results indicate that contraction profiles and contraction length are two major factors affecting the rheological behaviors of polystyrene melts in contraction flows based on the same contraction ratio and flow rate. V-shaped contraction, hyperbolic contraction, and elliptic contraction geometries can reduce stress concentration compared to abrupt contraction. Thus, during extrusion molding, it is better to use the elliptic contraction profile with adequate contraction length to eliminate or minimize defects in parts caused by stress concentration at the sharp edge exit. [ABSTRACT FROM AUTHOR]

In this study, a roasting-water leaching green process for highly selective lithium extraction from the cathode material of spent lithium iron phosphate (LiFePO4) battery was proposed. Using spent LiFePO4 as raw material and sodium bisulfate (NaHSO4) as an additive, the best roasting parameters were determined as follows: molar ratio of LiFePO4/NaHSO4 1:1.25, roasting temperature 400°C and roasting time 5 h. Under this condition, using pure water as a leaching agent, with leaching efficiency of 99.08% for Li and 0.12% for Fe, achieved the goal of high-selective leaching of Li. The study of the roasting mechanism shows that H and Li have similar external electron arrangements and coordination environments. Under the influence of temperature, the reactivity of the solid is improved, and the thermal, chemical reaction is initiated at the nanometer scale, resulting in the local rearrangement of particles, resulting in the reaction of LiFePO4 and NaHSO4 to generate LiNaSO4, which is helpful for subsequent leaching. This study can provide a process reference for high-selective recovery of Li in spent LiFePO4 batteries. [ABSTRACT FROM AUTHOR]

Transparent polylactic acid (PLA) fibers with Lumogen Red 305 (LR305) were prepared by melt spinning. The crystallization and melting behavior, absorbance spectra, emission spectra, mechanical properties, and the concentrator effect for a real solar cell of the PLA/LR305 fibers were characterized by differential scanning calorimetry (DSC), UV–Vis–NIR spectrophotometer, FL spectrophotometer, yarn tensile tester, and a digital multimeter (Victor VC980+), respectively. The results showed that the hot drawing improves the mechanical properties of the fibers while maintaining the optical properties. When the concentration of LR305 was 0.05 wt%, the breaking strength of the stretched fiber 22@217 (22% crystallinity, 217 diameters) and the as-formed fiber 3@205 (3% crystallinity, 205 diameters) were 69.3 and 182.7 MPa, respectively. Meanwhile, the absorbance intensity and luminescence intensity of 22@217 decreased only 6 and 11% compared with 3@205. When triple-drafted PLA/LR305 fibers with a concentration of 0.25 wt% were combined with the solar cell, the solar cell output current changed from 0 to 2.8 μA. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) support membranes containing varies functionalized multi-walled carbon nanotubes (F-MWCNTs) were prepared via phase inversion. Polyamide (PA) films were formed upon the support membranes by interfacial polymerization. The characteristics (include wettability, pore size, surface roughness, and porosity) of PVDF support membranes were improved by embedding F-MWCNTs into the polymer solution. PA films formed on the different support layers exhibited different morphology, separation performance, and formation mechanism. The results revealed that, as two key parameters, pore size and surface wettability showed dominant influence on the properties of the selective layer. Herein, we proposed a speculative conceptual model to explain the synergistic effect of pore size and surface wettability of F-MWCNTs/PVDF support membrane on interfacial polymerization mechanism. [ABSTRACT FROM AUTHOR]

Remote center of motion (RCM) constraint has attracted many research interests as one of the key challenges for robot-assisted minimally invasive surgery (RAMIS). Although it has been addressed by many studies, few of them treated the motion constraint with an independent workspace solution, which means they rely on the kinematics of the robot manipulator. This makes it difficult to replicate the solutions on other manipulators, which limits their population. In this paper, we propose a novel control framework by incorporating model predictive control (MPC) with the fuzzy approximation to improve the accuracy under the motion constraint. The fuzzy approximation is introduced to manage the kinematic uncertainties existing in the MPC control. Finally, simulations were performed and analyzed to validate the proposed algorithm. By comparison, the results prove that the proposed algorithm achieved success and satisfying performance in the presence of external disturbances. [ABSTRACT FROM AUTHOR]

Understanding the impact of complex boundary on the hydrodynamic properties of methane nanofluidic is significant for production optimization and design of energy-saving emission reduction devices. In the molecule scale, however, the microscopic mechanisms of the influence of the complex boundary on the hydrodynamic characteristics are still not well understood. In this study, a mixture boundary Poiseuille flow model is proposed to study the hydrodynamic properties and explore the molecular mechanisms of confined methane nanofluidic using the Non-equilibrium multiscale molecular dynamics simulation (NEMSMD). In order to investigate the influences of nonslip and rough boundary on hydrodynamic behavior of nanofluidic by the present model in one simulation, the coordinate transformation methods regarding the local symmetry is showed. Simulation results show that the atom number density, velocity and temperature profiles present significant differences near the nonslip boundary and rough wall surface. Moreover, the slip length of methane nanofluidic near the rough boundary decreases with the increasing of the temperature. Furthermore, the viscosity values are calculated by parabolic fit of the local velocity data based on the present model, which demonstrates that the impact of the nonslip boundary on the shear viscosity compared with the experiment result is less than one obtained using the rough boundary. In addition, the local contours of rotational and translational energy are plotted, which show that the rotational and translational energies of nonslip boundary are obvious higher than those of rough boundary. These numerical results are very significant in understanding the impact of complex boundary conditions on hydrodynamic properties in nanofluidic theory and the design of nano-devices. [ABSTRACT FROM AUTHOR]

This paper is concerned with simulating the viscoelastic flow of polystyrene melts in different contraction geometries based on single mode Rolie-Poly constitutive model. The 4:1 abrupt contraction flow of polystyrene melt is considered as a benchmark problem for validating the capabilities of Rolie-Poly model and numerical method and algorithm used in this work. Numerical results of the stress and velocity field illustrate that the present two-dimensional model and numerical method can reproduce predictions made by other published experimental and simulative results. To explore the rheological behaviors of the flowing polystyrene melt in different contraction geometries, the effect of die converging angle, contraction ratio and apparent shear rate on the flow field are discussed in detail. We compared some numerical results with the published experimental results, and reasonable matching between them was found. The present numerical results indicate that the die converging angle, contraction ratio and apparent shear rate are three important factors that are affecting the rheological behaviors of polystyrene melt in contraction flow. The magnitude of maximum PSD, first normal stress difference, and stretch ratio decrease with decreasing the converging angles, and largely reduced with a smooth entry shape. It shows that the shape of the convergence plays a major role in the foundation of extensional stress field, and a possible way to decrease the stress concentration at the contraction entrance of a die is to introduce a smooth entry shape. Numerical predictions of the distributions of principal stress difference (PSD), first normal stress difference, stretch ratio, shear stress, velocity, and so on in the flow field are also presented; the information contributes to a better understanding of the dynamic response of polymer melt forced into contraction geometries. [ABSTRACT FROM AUTHOR]

Quantifying the structure and composition of quasi-circular vegetation patches (QVPs) is key in identifying ecosystem function, which will help create a cost-effective nature-based solution for restoring the degraded wetland ecosystem in the Yellow River Delta (YRD), China. However, research on mapping plant communities of QVPs using remotely sensed data has not been conducted. In this study, we found that the pan-sharpened GF-1 imagery acquired in May was suitable for mapping plant communities of QVPs. Guided by field survey data and finer spatial resolution remotely sensed data, we constructed a simple decision tree classifier using the tasseled cap brightness (TCB), greenness (TCG), and topsoil grain size index (TGSI) of the pan-sharpened GF-1 image acquired in May. The classification results showed that the combination of the TCB and TCG components could efficiently distinguish the vegetation from non-vegetation, and the use of the TGSI was able to capture the variations in plant communities within QVPs in the YRD, China. However, the influence of the acquisition season and mixed pixels of GF-1 imagery (especially small canopy T. chinensis in small QVPs) on classification accuracy still needs further investigation. [ABSTRACT FROM AUTHOR]

Knowledge Graph Completion (KGC) aims at complementing missing relationships between entities in a Knowledge Graph (KG). While closed-world KGC approaches utilizing the knowledge within KG could only complement very limited number of missing relations, more and more approaches tend to get knowledge from open-world resources such as online encyclopedias and newswire corpus. For instance, a recent proposed open-world KGC model called ConMask learns embeddings of the entity's name and parts of its text-description to connect unseen entities to the KGs. However, this model does not make full use of the rich feature information in the text descriptions, besides, the proposed relationship-dependent content masking method may easily miss to find the target-words. In this paper, we propose to use a Multiple Interaction Attention (MIA) mechanism to model the interactions between the head entity description, head entity name, the relationship name, and the candidate tail entity descriptions, to form the enriched representations. In addition, we try to use the additional textual features of head entity descriptions to enhance the head entity representation and apply the attention mechanism between candidate tail entities to enhance the representation of them. Besides, we try different scoring functions to increase the convergence of the model. Our empirical study conducted on three real-world data collections shows that our approach achieves significant improvements comparing to state-of-the-art KGC methods. [ABSTRACT FROM AUTHOR]

Aberrant T helper-2 (Th2) responses play a critical role in the pathogenesis of allergic diseases. The underlying mechanism is to be further investigated. It is reported that soluble CD83 (sCD83) has immune-regulatory effects. This study aims to investigate the role of sCD83 in the regulation of Th2 polarization. Blood samples were collected from pediatric patients with food allergy (FA). The Th2 response was analyzed by pertinent immunological approaches. An FA murine model was developed to test the role of sCD83 in the regulation of FA response. We found that the serum sCD83 levels were lower in FA patients. A negative correlation was detected between serum sCD83 levels and serum Th2 cytokine levels. The presence of sCD83 suppressed Th2 cell differentiation and antigen-specific Th2 cell activation. sCD83 upregulated the T-bet expression and suppressed the GATA3 expression in CD4+ T cells. Administration of sCD83 suppressed experimental FA. Pediatric FA patients have low serum sCD83 levels. Administration of sCD83 can alleviate experimental FA via suppression of aberrant Th2 polarization. [ABSTRACT FROM AUTHOR]

Purpose: Soil bulk density and hydraulic conductivity are two of many key factors for vegetation establishment and the other way around. Variations in them may cause patchy vegetation distribution in arid and semiarid areas. Characterizing their spatial variations in relation to quasi-circular vegetation patches (QVPs) is important for the effective revegetation of wetlands in the Yellow River Delta (YRD), China. Materials and methods: This study investigated the variations of soil bulk density and hydraulic conductivity based on 86 soil bulk density and 63 hydraulic conductivity samples within a quasi-circular vegetation patch area in the YRD. The nonparametric Mann-Whitney U and Kruskal-Wallis H tests, respectively, were used to evaluate the differences in soil bulk density and hydraulic conductivity between the QVPs and bare soil areas. Results and discussions: There were significant differences in soil bulk density and hydraulic conductivity between QVPs and bare soil areas. Conversely, there were no significant differences in the two parameters among different QVPs. The average QVP bulk density and hydraulic conductivity (2.0 cm suction) were 12.4% lower and 191.8% higher, respectively, than those of bare soil areas. Plant species communities within QVPs did not significantly differ in terms of their influences on hydraulic conductivity but did differ in terms of their impacts on soil bulk density. Soil bulk density increased from the QVP centers to their edges whereas the opposite was observed for hydraulic conductivity. This finding indicated that QVPs drastically increase soil hydraulic conductivity, and soil bulk density influenced the spatial distribution of plant species communities within QVPs. Conclusions: This study expanded our understanding of occurrence and encroachment of QVPs in the YRD, may help understand spontaneous plant colonization and succession mechanism and lay the foundation for developing adaptive wetland restoration strategies in the YRD. [ABSTRACT FROM AUTHOR]

Soil moisture is an important resource for plant growth on the arid and semi-arid Loess Plateau of China where the "Grain for Green" project was launched in 1999, but there has been no systematic evaluation of soil moisture from the effects of ecological restoration at a regional scale. We systematically assessed 63 published studies during 2000–2015, including 2050 observations at 68 sites on the Loess Plateau with the aim of determining soil moisture changes and the factors influencing those changes. We found that, after land use conversion, soil moisture decreased by 17% in the upper 100 cm soil layer and that tree plantations and shrub lands appeared to cause soil moisture depletion which became increasingly serious with soil depth. The decrease of soil moisture was significantly influenced by the planting species in all restoration types (tree plantations, shrub lands, and grasslands). We also found that tree plantations and grasslands converted from farmlands consumed more soil moisture than from wasteland (including bare land, abandoned land and wild grasslands). Artificial restoration led to significant soil moisture reduction, but natural restoration had little effect on soil moisture. Therefore, natural restoration should be an alternative restoration practice on the Loess Plateau. These results will provide helpful information for artificial afforestation and planning ecological restoration campaigns for policy makers on water-limited regions. [ABSTRACT FROM AUTHOR]

Weld lines are one of the typical quality issues of injection molded parts. They are unavoidable even for moderate complex products. To explore the formation of weld lines in injection molding, a flow model based on viscoelastic constitutive equation is presented in this article to predict and evaluate of weld lines location and properties, in which Rolie-Poly constitutive equation is used to describe the viscoelastic properties of polymer melts and level set method is used to capture melt front. Furthermore, the formation and evolution processes of weld lines are investigated by co-injection molding technique in simulation, since the processes are determined by the flow front and rheological history of the melt streams. Numerical results show that weld lines can be predicted accurately, and the formation and evolution processes of weld line can be shown more clearly by co-injection molding technique. In addition, properties of polymer melt such as velocity, pressure, principal stress difference, and molecular orientation in the weld line regions are investigated and presented. [ABSTRACT FROM AUTHOR]

The microstructure and system dynamics of methane nanofluidic are important to determine the flow properties. In this study, we use non-equilibrium multiscale molecular dynamics simulation (NEMSMD) to investigate the microstructure and system dynamics of methane nanofluidic confined by rough silicon atomic walls. To capture the detailed atomic microstructure of methane moving in rough nanochannel accurately, the modification of OPLS methane fully atomic model is employed. The average number density distributions of C (H) atom, average velocity profile, velocity autocorrelation function and projection radial distribution function (XOY-, XOZ- and YOZ planes) plots give a clear observation of the impacts of different conditions (roughness, body driving force, fluid–wall interaction strength and cutoff radius) on the methane Poiseuille flow in nanochannel. The projection radial distribution functions and diffusivity appear anisotropic, and seem to be affected more significantly by roughness, fluid–wall interaction strength and cutoff radius than body driving force in the whole channel region. Moreover, the body driving force and cutoff radius also play an important role in methane nanofluidic simulation using NEMSMD. The present simulation results are very meaningful for the design of energy-saving emission reduction nanofluidic devices. [ABSTRACT FROM AUTHOR]

Purpose: Deep soil moisture has been considered to be critical for plant survival in water-limited ecosystems. The limited precipitation on the semi-arid Loess Plateau is the only water source for soil moisture and is unevenly distributed throughout the year. Characterizing the seasonal changes in deep soil moisture in relation to land use types and structures is important for the sustainability of vegetation restoration in this region.Materials and methods: A total of 27 experimental sites along seven transects were selected in the Jiegou catchment on the semi-arid Loess Plateau. These sites were covered by five land use types: native grassland, traditional farmland, abandoned farmland, and 5-year and 7-year Robinia pseudoacacia (RP) forestlands. Soil moisture measurements were conducted during three seasons (spring, summer, and fall) at soil depths of 0 to 5 m in 0.2-m increments, and 2025 disturbed soil samples were collected to determine the gravimetric soil moisture content using the oven-dry method (24 h at 105 °C). The depth-averaged soil moisture was compared among different seasons and land use types using one-way ANOVA and significance tests.Results and discussion: Among the seasons, the depth-averaged soil moisture had the following order: fall > spring > summer. In the shallow layers (above 2 m), soil moisture in summer was significantly lower than that in spring and fall (p < 0.05). The vertical distribution characteristics of soil moisture (0-5 m) were similar among the land use types during each season but different among the seasons for each land use type. In general, the depth-averaged values of soil moisture among the land use types were on the order of native grassland > farmland > forestland. This finding indicated that afforestation drastically decreased deep soil moisture, particularly in summer. Furthermore, the different land use structures significantly influenced the spatial distribution of deep soil moisture during each season.Conclusions: This study highlights the seasonal changes in both shallow and deep soil moisture under various land use types, which provides insights into the sustainable use of deep soil moisture and rational land use management on the semi-arid Loess Plateau of China. [ABSTRACT FROM AUTHOR]

Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the relationship between sandy desertification and surface characteristics in these regions are lacking. We monitored the surface characteristics and their changes in time using information about soil, vegetation, and landforms in the Badain Jaran Desert (BJD), Tengger Desert (TD), and Ulan Buh Desert (UBD) in the northern China. The monitoring was done using tasseled cap angle (TCA), disturbance index (DI), and topsoil grain size index (TGSI) from Moderate Resolution Imaging Spectroradiometer (MODIS) images combined with a decision tree classification. Results showed that the TD had higher topsoil fine sand content, and the ratio of non-vegetated to vegetated areas was similar with that in the UBD. Northeast-southwest coarse sand dunes with thin interdune (NECTI) dominated the BD, fine sand dunes (FSD) dominated the TD, and a combination of northeast-southwest coarse sand dunes with wide interdune (NECWI) and northwest-southeast coarse sand dunes with wide interdune (NWCWI) dominated the UBD. From 2000 to 2015, in the BJD the area of the NECTI, non-sand dune (Non) and potential sand sources (PSS) increased, whereas the area of the NECWI, FSD and NWCWI decreased, indicating a improve process in the BJD. In the TD, the area covered by Non increased, whereas the area covered by PSS, NECWI, NECTI, FSD, and NWCWI decreased from 2000 to 2015. The area covered by the various surface characteristic types fluctuated annually in the UBD from 2000 to 2015. Changes in surface characteristics reflect the combined effects of natural conditions and human activity. The findings of our study will assist scientists and policy makers in proposing different management techniques to combat sandy desertification for the different surface characteristics of these regions. [ABSTRACT FROM AUTHOR]

They found that there are lots of areas with low sea ice concentration south of 78°N, while sea ice concentration and thickness increase with the latitude to north of 78°N. Qin et al. (2021) retrieved the sea surface wind speed from Sentinel-1 SAR images using conventional retrieval and machine learning methods. Editorial Improving the observation and prediction capabilities for Arctic marine environment: from the perspective of Arctic Shipping Hui Wang 1, Qizhen Sun 1 *, Lin Zhang 1, Xi Liang 1, Qinghua Yang 2, Na Liu 1, Chunhua Li 1, Qingsheng Liu 3, Bingrui Li 4, Qian Feng 5, Xiao Cheng 6, Yi Yu 7 1 National Marine Environmental Forecasting Center, Beijing 100081, China 2 School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China 3 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Science, Beijing 100101, China 4 Polar Research Institute of China, Shanghai 200136, China 5 National Satellite Ocean Application Service, Beijing 100081, China 6 School of Geospatial Engineering and Science, Sun Yat-sen University, Zhuhai 519082, China 7 Donghai Navigation Safety Administration, Ministry of Transport, Shanghai 200086, China Received 5 December 2020; accepted 31 December 2020 © Chinese Society for Oceanography and Springer-Verlag GmbH Germany, part of Springer Nature 2021 In recent decades, Arctic climate is warming at a rate of almost twice the global average (Osborne et al., 2018). Numerical prediction models for weather, sea ice, and ocean of the Arctic need to be developed, so that short-term forecasts and mid- and long-term predictions can be provided. [Extracted from the article]

Biodegradable multiblock copolymers based on poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)] (PHBV), poly(ε-caprolactone) (PCL), and polyhedral oligomeric silsesquioxane (POSS) were synthesized by one-step copolymerization with 1,6-hexamethylene diisocyanate (HDI) as a coupling agent. The chemical structures, molecular weight, and polydispersity index of the PHBV/PCL/POSS multiblock copolymers were confirmed by 1H NMR, FTIR, and gel permeation chromatography (GPC). XRD analysis illustrated that PHBV and POSS blocks in multiblock copolymers with high content of PHBV and POSS could crystallize to form separate crystalline phases. DSC analysis indicated that the mutual interference of crystallization of PHBV, PCL, and POSS blocks existed. Compared with the crystallinity of PHBV-diol and original PHBV, the crystallinity of PHBV block decreased from 54.8 (original PHBV) and 49.5 (PHBV-diol) to 25.5%. TG measurement revealed that thermal degradation of the multiblock copolymers proceeded by a four-step degradation process and the thermal degradation behavior of PHBV block was similar to that of the original PHBV. The melt processing window of multiblock copolymers was much wider than that of the original PHBV. The results of tensile testing showed that the tensile strength at break of the fibrous membranes of multiblock copolymers increased by 37.5% from 0.8 to 1.1 MPa and the elongation at break reached 307.8%. [ABSTRACT FROM AUTHOR]

Two kinds of composite filter materials were prepared by regulating the structure of melt-electrospinning polypropylene (PP) webs. The self-designed multi-nozzle melt-electrospinning device was used to produce PP webs which deposited on PP spunbonded nonwoven. Firstly, the composite filter materials with different thickness and ratios of coarse/fine fibers were prepared, and the effect of the thickness and the ratio of coarse/fine fibers on filtration properties were studied. The results showed that the filtration efficiency and pressure drop increased as thickness increased. In addition, compared with the general filters which were composed of coarse or fine fibers, the filters with coarse/fine fibers had 'low pressure drop' under the similar filtration efficiency. In the case of the ratio of coarse/fine fiber about 2:2, this filter achieved optimal performance. When the thickness was 0.42 mm, its filtration efficiency for particles more than or equal to 2.0 μm could reach more than 95 %. Its pressure drop and air permeability were 18.13 Pa and 54.69 mm/s, respectively, while those of general filter were 38.67 Pa and 10.02 mm/s, respectively. After that, the composite filter materials composed of various angles of oriented webs were produced. The results showed that the filtration efficiency for particles with the size of more than or equal to 2.0 μm was higher than that of filters composed of one angle of oriented webs. In addition, the lower the orientation was, the lower the pressure drop was. [ABSTRACT FROM AUTHOR]

In this work, the viscosity-temperature-density relationship of methane is investigated for three fully atomistic models (RISM, OPLS and MOPLS) and the corresponding coarse-grained models (CGRISM, CGOPLS and CGMOPLS) by studying the Poiseuille flow inside a silicon nano-channel using molecular dynamic simulation. In order to solve the interaction problem of nano-channel atom and methane molecule, the coarse-grained methane model and the classical Berthelot-Lorentz mixing rules are employed. The optimized coarse-grained methane models are determined using the relative entropy minimization method. The density distribution, stress force profile and velocity profile of coarse-grained models are compared with the fully atomistic models for different nano-channel widths. It is concluded that the results of coarse-grained model are in reasonable agreement with those of the corresponding fully atomistic model. Furthermore, the value of viscosity is calculated by fitting the velocity profile to the continuum solution from the Navier-Stokes equations and then compared to experimental value. The results show that the MOPLS and CGMOPLS models could well predict the viscosity of methane fluid, while the OPLS model performed worst. All simulation results indicate that the coarse-grained models can be used to predict the viscosity of methane fluid accurately. [ABSTRACT FROM AUTHOR]

A perovskite LaFeMgO ( x = 0, 1/3) compound was prepared by the sol-gel method and characterized by TG-DTA, XRD, SEM, and XPS. The infrared (IR) emissivity of the nanoscale LaFeMgO powder synthesized after heat preservation for 2 h at 1300 °C was as high as 0.93 in the range 0.2-2 μm, an increase of 121 % than that of undoped LaFeO. The increase in the IR emissivity of LaFeMgO can be mainly attributed to the substitution of Mg with Fe in the LaFeO lattice. The substitution of Mg with Fe introduced the energy level of Fe impurity and generated oxygen vacancies, thus increasing the impurity and oxygen vacancy absorption. The lattice distortion caused by doping strengthened the lattice vibration absorption. The polaron hopping of electrons between Fe and Fe also significantly strengthened the absorption properties within the corresponding spectrum area of Mg-doped LaFeO. Graphical Abstract: The absorptivity of LaFeO was stable at ~0.94 in the range 200-500 nm and decreased drastically after 500 nm, and the absorption edge was ~600 nm. The absorption of Mg-doped LaFeO sample was 0.93 in the range 200-2000 nm. Mg doping significantly improved the absorptivity of LaFeO (0.75); moreover, the absorption edge red-shifted to the spectral region at ~2000 nm. This was caused by the introduction of Mg that increased the oxygen vacancy concentration in LaFeO valence band and enhanced the intraband absorption, thus strengthening the absorptivity to some extent. [ABSTRACT FROM AUTHOR]

Firstly, the effects of the spinning temperature, spinning voltage, tip-to-collector distance and ambient temperature on the diameter of melt-electrospinning polypropylene (PP) fibers were studied. The results showed that with the increase of the spinning temperature, spinning voltage and tip-to-collector distance, the fiber diameters first decreased and then increased. However, when the ambient temperature increased, the fiber diameters increased gradually. Secondly, based on the previous results, the response surface methodology (RSM) was used to investigate the combined effects of processing parameters on fiber diameters and establish a second-order polynomial equation to predict the fiber diameter. The results showed that the effect order of four factors on fiber diameter was as follows: spinning temperature > tip-to-collector distance > ambient temperature > spinning voltage. Moreover, the fiber diameter predicted by response surface analysis fitted well with the experimental result. Finally, three layer melt-electrospinning PP webs with different fiber diameters were online compounded with conventional non [ABSTRACT FROM AUTHOR]

The flow-induced stresses which arise during the filling stage have significant influences on the mechanical and optical properties of injection-molded products. The prediction of flow-induced stresses in mold-filling process is a challenging problem, which includes viscoelastic polymer melt free surface flow. Thus, this paper presents a three-dimensional (3D) non-isothermal two-phase flow model to quantitative predict the flow-induced stresses in polymer mold-filling process based on the XPP model. In this model, the governing equations for gas and viscoelastic melt are united into a system namely the generalized Navier-Stokes equations. In order to improve the stability of the numerical method in 3D, an enhanced treatment of stress solid boundaries is proposed. The stresses on solid boundaries are calculated using an effective second-order Runge-Kutta method. The model is successfully solved by using the finite volume method, and the melt front is accurately captured by level set method. The validity of the method is verified by two benchmark problems. Then the mold-filling process of a rectangular plate is studied numerically, obtaining the evolutions of flow-induced stresses at different levels along the gap-wise direction, which can not be simulated by 2.5D model. The predicted flow-induced birefringence is in agreement with the experimental result reported in the literature. Furthermore, the effects of injection velocity and some model parameters of XPP model on flow-induced stresses are numerically predicted. The numerical results show that the 3D simulation technology can effectively predict the flow-induced stresses and birefringence in non-isothermal viscoelastic polymer mold-filling process. The results can provide the theory foundation for improving the properties of products in actual production processes. [ABSTRACT FROM AUTHOR]

The flow behavior of polystyrenes is investigated numerically for a cross-slot geometry using Rolie-Poly model with finite extensibility, and governing equations for the polystyrene melts are solved by finite volume method with domain extension technique on the collocated grid. The effect of molecular weight, flow rate, and two kinds of Weissenberg numbers on the principal stress difference (PSD) profiles are discussed detailedly. The microstructures of polymer melts, including molecular orientation, extension, and deformation, are also investigated and presented in this paper. We found that the orientation of Weissenberg number is the major factor affecting the PSD profiles and the performance of the Rolie-Poly model has been improved greatly by introducing finite extensibility at high extension rate. The numerical results are consistent with the available experiment results, which demonstrate the capabilities of single-mode Rolie-Poly model with finite extensibility to simulate the flow behavior of polystyrenes and the numerical method developed in this paper. [ABSTRACT FROM AUTHOR]

A fibrous composite membrane consisting of a chitosan (CS) barrier layer and a poly(hydroxybutyrate-cohydroxyvalerate) (PHBV) fibrous substrate was manufactured as a filter for water purification. The PHBV fibrous supporting layer was fabricated via electrospinning technique, and then the CS solution cast on the PHBV fibers to form the top barrier layer. The structural morphology, mechanical property and adsorption capability of the PHBV/CS membranes were thoroughly investigated. Three heavy metal ions were used to evaluate the equilibrium absorption capacities of the chosen membranes. The equilibrium absorption capacities for Cu(II), Pb(II) and Cd(II) were 64.08 mg/g, 90.32 mg/g and 148.96 mg/ g, respectively. Meanwhile, the rejection ratio of PHBV/CS composite membrane for two disperse dyes could reach to 99 %. The results indicated that PHBV fibrous substrate could not only enhance the mechanical strength of the top barrier layer, but also improve the water permeation of the membrane. This study extended the application of an environmentally friendly material in the water purification without causing much trouble about scrap film. [ABSTRACT FROM AUTHOR]

Nanocomposites of polyphenylene sulfide (PPS) were prepared with a benzimidazolium surfactant used as organic modification for the montmorillonite (MMT) by melt blending. The benzimidazolium-modifided MMT (Bz-MMT) exhibited a large interlayer spacing of 3.26 nm and showed a high thermal stability compared to the commonly used clay modified by alkyl ammonium salts (DK-1N). The morphology of the polyphenylene sulfide (PPS)/Bz-MMT nanocomposites were evaluated by X-ray diffraction (XRD) and transmission electron microscope (TEM). The results showed good overall dispersion of the MMT in PPS matrix. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to evaluate the thermal properties of polymer/clay nanocomposites. The results of DSC showed the addition of MMT resulted in heterogeneous nucleation crystallization of PPS. The results of TGA showed the thermal stability of the polymer/clay nanocomposits was enhanced. The rheological properties of nanocomposites were also evaluated by a Anton Paar rheometer. The results indicated that the addition of Bz-MMT nanoplatelets affected the linear viscoelastic behavior of the PPS matrix by increasing the viscosity. [ABSTRACT FROM AUTHOR]

Cetyl trimethyl ammonium bromide (CTAB) was used for the intercalation modification of nano-montmorillonite (MMT). The spectra of Fourier transform infrared spectrometer (FTIR) and X-ray diffraction (XRD) suggested that CTAB had intercalated into the layers of MMT. And the interlayer spacing of MMT increased from 1.198 to 3.616 nm. The thermogravimetric analysis (TGA) curves of organic montmorillonite (OMMT) showed three-step degradation. The scanning electron microscope (SEM) photographs showed that surface morphology of MMT remained unchanged. Then polyphenylene sulfide (PPS)/organic montmorillonite (OMMT) composites were prepared by melt blending. And composites were treated at 180 °C for 24 h. The results of SEM showed that OMMT had good dispersion behavior and adhesion with PPS. The results of differential scanning calorimetry (DSC) showed the addition of OMMT resulted in heterogeneous nucleation crystallization of PPS. The results of TGA showed there was a good improvement of the thermal stability of PPS. The FTIR and color measurement analysis showed the addition of OMMT could improve the thermal oxidation stability. [ABSTRACT FROM AUTHOR]

The PLA/PAE blends with four different weight ratios were prepared by melt mixing. PLA and PAE in PLA/PAE blends were almost immiscible while the weak interaction between PLA and PAE existed. The sub-micrometer PAE domains were dispersed in PLA matrix uniformly. The physical aging of PLA could be inhibited by introducing PAE. For PLA/PAE, the structure formed by physical aging at room temperature induced the accelerated crystallization of PLA during heating. However, for neat PLA, the structure formed by physical aging had a negligible effect on the crystallization of PLA during heating. The isothermal crystallization kinetics of neat PLA and PLA/PAE were analyzed by Avrami theory. The values of Avrami exponent were within the range 2.1–3.0. The crystallization rate of PLA was enhanced significantly by addition of PAE. [ABSTRACT FROM AUTHOR]

This paper studies magnetic properties and composition of granulite-facies rocks of both the Neogene and Archean continental lower crust in the Neogene xenolith-bearing Hannuoba(汉诺坝) alkaline basalt and the exposed lower crustal section in the Archean Huai'an(淮安) terrain (Wayaokou (瓦窑口)-Manjinggou(蔓菁沟 profile), the northern North China Craton. It provides a unique opportunity for a comparative study of magnetic properties and composition of both the Archean and Neogene continental lower crust. We measure magnetic parameters (susceptibility κ and magnetic hysteresis parameters, such as saturation magnetization J, saturation isothermal remanent magnetization J, and intrinsic coercivity H) of eleven Hannuoba lower crustal xenoliths and nine terrain granulites from the Archean Huai'an terrain. Results indicate that the average values of κ, J and J of Archean granulites are 4 122×10 SI, 523.1 A/m and 74.9 A/m, respectively, which are generally higher than those of granulite-facies xenoliths (1 657×10 SI, 163.9 A/m and 41.9 A/m, respectively). These two types of granulites contain ilmenite, (titano) magnetite, minor hematite and some 'magnetic silicates' (clinopyroxene, plagioclase and biotite). The Mg-rich ilmenite in granulite-facies xenolith is relatively higher than that in terrain granulites. We observe a more evolved character as higher magnetic as well as lower Sr/Nd, Cr/Nd, Ni/Nd, Co/Nd and V/Nd ratios in terrain granulites. These differences in magnetic characteristics reflect their different origins and evolutions. The high magnetization of granulites in the Huai'an terrain represents magnetic properties of the Archean continental lower crust, and low magnetization of granulite-facies xenoliths represents magnetic properties of the Cenozoic lower crusts in the northern North China Craton. [ABSTRACT FROM AUTHOR]

Two types of soil (fluvisols and anthrosols) were collected from different environmental settings (suburb and industrial area) in Wuhan, central China, aiming to examine the applicability of magnetic mapping for heavy metal pollution of urban soil in a large region. Magnetic measurements and chemical analysis indicated elevated magnetization and heavy metal concentrations of topsoils in the industrial area. Magnetic susceptibility (χ), anhysteretic remanent magnetization (ARM) and saturation isothermal remanent magnetization (SIRM) of fluvisols are much higher than those of anthrosols, but contrary for frequency-dependent susceptibility, indicating that soil magnetism strongly depends on the soil type/condition. Predominant magnetic carrier in topsoils in industrial area is pseudo-single-domain/multi-domain magnetite. Environmental scanning electron microscope/energy dispersive X-ray examination of the magnetic extracts from these topsoils revealed abundant spherical particles with diameters of 10-50 μm that are rich in iron-oxides, and could be attributed to the nearby industrial activities (e.g., steel work and power generation). Significant correlations were observed between magnetic concentration-related parameters (e.g., χ, ARM and SIRM) and concentrations of Cu, Pb, Zn, Hg and Tomlinson pollution load index. These results proposed that magnetic proxy mapping of soil pollution is an effective, fast and inexpensive tool for delineation of heavy metal pollution. However, interpretation of magnetic properties for such a purpose must be done on a site-specific basis, taking into account the possibilities of pedogenic enhancement/depletion under the specific soil conditions. [ABSTRACT FROM AUTHOR]

Telechelic hydroxylated poly(3-hydroxybutyrate-co-3-hydroxyvalerate)s (PHBV-diols) were synthesized by transesterification with ethylene glycol, which could be used as the macromonomers for synthesis of block copolymers. PHBV-diols owned particular thermal properties. PHBV-diols had much lower the melting temperatures ( T s) and better thermal stability than original PHBV. With the decrease of molecular weight, T s of PHBV-diols decreased gradually and maximum degradation temperatures ( T s) increased gradually. T -T of PHBV-diol could increase by 57.9 °C in comparison with original PHBV. It was meaningful that PHBV block in the block copolymers based on PHBV-diol owned the good thermal stability and low melting temperature of its precursor PHBV-diol, which widened greatly the melt-processing window of PHBV. In addition, thermal degradation kinetics was studied by Ozawa method, the integration method and Kissinger method. The results showed that the thermal degradation of original PHBV and PHBV-diols proceeded by at least two steps including a random degradation process and subsequent thermal degradation process due to the auto-accelerated degradation reaction. [ABSTRACT FROM AUTHOR]

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Biodegradable block copolymers containing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly ( ɛ-caprolactone) (PCL) units (PHCLs) with different contents of PCL block were synthesized successfully by using telechelic hydroxylated PHBV (PHBV-diol) with low molecular weight as a macroinitiator to initiate ring-opening bulk polymerization of ɛ-caprolactone ( ɛ-CL). The chemical structure and molecular weight were characterized by 1H NMR, FTIR and GPC. The PHBV and PCL blocks in PHCLs were miscible in amorphous state, and formed separate crystalline phases with lower crystallinity than corresponding homopolymers, which was characterized by DSC and WAXD. The results of TGA showed that PHCLs underwent a two-step thermal degradation process. The thermal degradation process of PCL blocks was significantly different from PCL homopolymers. The activation energies of thermal degradation of PCL blocks calculated by Horowitz and Metzger method were much higher than that of each step of thermal degradation of PCL homopolymers. [ABSTRACT FROM AUTHOR]

The Sulu (苏鲁)-Dabie (大别) orogen in East-Central China formed during the subduction and collision of the Yangtze block with the North China block in Early Mesozoic (240-225 Ma). Constraints on the nature and derivation of eclogites, which are a significant component of the orogen, can provide useful information about subduction-zone metamorphism and crust-mantle interaction. The U-Pb ages, Hf-isotope ratios and trace-element compositions of zircons in eclogites from the Jiangzhuang (蒋庄) (Jiangsu (江苏) Province) and Rongcheng (荣成) (Shandong (山东) Province) areas indicate that the protoliths of the eclogites derived from ultramafic-mafic complexes or mafic intrusion in the subducted continental lithosphere. The upper intercept age of 852±10 Ma and high ɛ (up to 14.7) of the Neoproterozoic zircons in a Jiangzhuang sample indicate that the protoliths represent products of the Neoproterozoic addition of juvenile materials to the older (i.e., Paleo-Mesoproterozoic) continental crust. The zircon ages of eclogites from both localities mainly record the Triassic (230-220 Ma) metamorphism, consistent with the formation of the Sulu orogen in Early Mesozoic. The lower intercept age of 316±4 Ma in a Jiangzhuang sample suggests that thermal activity relating to the paleo-Tethyan in Late Carboniferous also affected the eclogitic protolith. [ABSTRACT FROM AUTHOR]

Magnetic measurements and heavy metal analyses were performed on street dusts from the main urban area of Chibi (赤壁) City, Hubei (湖北) Province, China. Results revealed that a PSD/MD (pseudo-single-domain/multi-domain) magnetite-like phase dominates the magnetic phases of the street dust. Concentration-related magnetic parameters, such as magnetic susceptibility ( χ), anhysteretic remanent magnetization (ARM), and saturation isothermal remanent magnetization (SIRM) of samples increased in the main roads but appeared lower in the landscape area of the Lushui (陆水) Lake and closely correlated with the concentration of heavy metal Fe, Cu, and Co, and the correlation coefficients are 0.786 for Fe- χ, 0.548 for Cu- χ, and 0.580 for Co- χ, respectively. However, much strong correlations between SIRM and the concentrations of heavy metal suggest that SIRM is a better indicator for heavy metal pollution in the street dust in the study area. The magnetic particles in the street dust are mainly derived from anthropogenic activities, such as vehicle emissions, abrasion of tires, coal combustion, cement works, and building materials. These results make it possible to use magnetic techniques as simple, rapid, and nondestructive tools for assessing the heavy metal pollutions in urbanization process. [ABSTRACT FROM AUTHOR]

Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process in landscape ecology, the methodology of landscape information Tupu in studying the swing process of the Yellow River (YR) over the Yellow River Delta (YRD) during 1855–2000 has been demonstrated. The main content includes: (1) methodology of landscape information Tupu; (2) evolution process Tupu of YR rump channels; (3) evolution process Tupu of the 7 pieces of subdeltas in YRD during 1855–2000; (4) landscape information Tupu of the modern YRD and the current YRD; (5) landscape information Tupu of YR rump channels on the 7 pieces of subdeltas during 1855–2000; and (6) corridor-matrix landscape information Tupu by YR swings. The methodology of landscape information Tupu here is still primary but we hope that it could provide a new tool for exploring an integrated research on spatiotemporal approaches for landscape “pattern and process”. [ABSTRACT FROM AUTHOR]

By using data on the 1:100 000 aeromagnetic anomalies of the Sulu orogenic belt, we designed three simulated geotraverses, in which deep seismic reflection and other geophysical investigations have been completed. Based on the features of magnetism of the three profiles, and under the constraints of deep seismic reflection data, together with the magnetism of the core petrology at the Chinese Continental Scientific Drilling (CCSD) pilot-hole and areal geology, the three inversions of magnetic anomalies are carried out. The characteristics of terrane structure are presented: the rocks are mostly composed of eclogite, marble, and gneiss at the depth of 5 km. At the depth between 5 and 7 km under the surface, inverse magnetic bodies are mainly the ultra high pressure metamorphic (UHPM) rock slices containing a lot of coesite-bearing eclogite. At the depth between 7 km and the bottom of upper crust are the rocks of the gneiss, granite and granite diorite that underwent ultra high pressure metamorphic process. Middle crust (10–19 km) is mostly composed of UHPM gneiss and granite that intruded later. The rocks of acid and basic granulite dominate the lower crust. Based on the inversed results of the three simulated geotraverses, we know that the UHPM rock slices of the three profiles are dipping north, stacking each other and being uplifted to the earth’s surface, which may be the result of the North China craton’s subduction and exhumation in the Triassic. [ABSTRACT FROM AUTHOR]

Detailed magnetic measurements and geochemical analyses were performed on 114 sediment samples collected from the East Lake, Wuhan city, China, to establish a possible link between the enhanced concentration of anthropogenic magnetic particles and heavy metals with known sources. Relatively higher magnetic susceptibility values (mass-specific, χ, >150 × 10−8 m3 kg−1) were observed for samples near the pollution sources: e.g. the Wuhan Iron and Steel Company (WISC), the Qingshan Thermal Power Plant (QTPP), the banks (driveways) of the lake and near the sightseeing route of yachts on the lake. Moreover, χ is positively correlated to the concentration of Pb (correlation coefficient r = 0.682), but negatively or weakly correlated with both Zn and Cu. In contrast, anhysteretic remanent magnetization (ARM) is significantly correlated with these major heavy metals ( r = 0.645 for Zn–ARM, 0.699 for Pb–ARM and 0.841 for Cu–ARM, respectively), which indicate that ARM serves a better indicator for the pollution of heavy metals in this lake. Thermomagnetic analysis combined with magnetic hysteresis measurements revealed that magnetites in the pseudo-single-domain/multidomain grain-size regions are dominant. Scanning electron microscopy and energy dispersive X-ray examinations of the magnetic extracts showed that these Fe-rich particles have different morphologies: orange-peel structure, hollow structure with adhered smaller particles, Zr-rich melted-like irregular particles, pear-shaped spherules and spherules with slick surfaces. These features are typical for particles produced by anthropogenic activities. Because of the genetic relationship between the environmental setting of the East Lake and the nearby pollution sources, this study suggests that in situ magnetic surveys are sensitive to evaluate the environmental pollution on the lake bottom. [ABSTRACT FROM AUTHOR]

A series of basket-shaped hosts with ester-crown handles have been synthesized by treating oligoethylene glycol bischloroacetates [ClCH2CO(OCH2CH2) nOCOCH2Cl, n = 1, 2, 3, 4] and 1,2-bis(hydroxyethoxy)benzene bischloroacetates with a diphenylglycoluril-based molecular clip, 1,3:4,6-bis(3,6-dihydroxy-1,2-xylylene)tetrahydro-3a,6a-diphenylimidazo[5,5]imidazole-2,5(1 H, 3 H)-dione ( 1), in dimethyl sulfoxide using K2CO3 as a base in yields of 15, 35, 40, 38, and 20%. Their structures were identified by nuclear magnetic resonance and mass spectrum. The reaction conditions were also studied and optimized. [ABSTRACT FROM AUTHOR]

Mg-Al, Zn-Al and Ni-Al hydrotalcite-like compounds with high crystallinity were synthesized by using the decomposing property of urea at high temperature. The crystallinity and the regularly of the samples were much preferable to those synthesized by other methods. [ABSTRACT FROM AUTHOR]

Mg/Al mixed oxides used as supports for platinum catalysts with Mg/Al molar ratios of 2-6 were obtained by thermal decomposition method. The effects of compositions and catalytic properties were studied by TPD, BET, XRD and TG-DTA techniques. Synthesis of o-phenylphenol (OPP) from Dimer was investigated over Pt/CHT catalysts and compared with Pt/Al2O3. These catalysts showed a conversion of 93.8% and a selectivity of 87.9%. [ABSTRACT FROM AUTHOR]

Reports on the discovery of a vast high magnetic body located at a depth of about 20 kilometers on the west side of the Tanlu fault and at about 25 km on the east side of Tanlu fault beneath the Sulu area. View that the magnetic body is an Archean metamorphic plate and belongs to the North China block; Importance of the discovery in the reconstruction of the structure model of the Sulu organic belt.

Au/ZnO catalysts prepared by co-precipitation method with different Au:Zn atomic ratios have been studied for room-temperature CO oxidation in the presence/absence of water in the feed stream. The catalysts exhibited excellent catalytic activity and stability compared with pure ZnO. Furthermore, it was found that the lifetime of Au/ZnO catalysts was improved significantly by increasing CO concentration but decreased by addition of HO in the feed stream. The deactivation may be related to the sintering of metallic gold and the accumulation of carbonate-like species in the catalyst. [ABSTRACT FROM AUTHOR]