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Human resources and potential secondary disasters are often neglected in the existing emergency resource allocation methods. This paper presents a multistage assignment model for rescue teams to dynamically respond to the disaster chain and develops three priority scheduling strategies defined under the burden-benefit accord principle. A designed NSGA-II, C-METRIC and fuzzy logic methods were developed to solve the above multi-objective integer nonlinear programming model. Finally, the experimental scenarios results indicated that the overall performance of the proposed method was satisfactory in comparison with current method regardless of whether the secondary disasters occurred sooner or later. It was demonstrated that the three proposed priority scheduling strategies outperformed the others; however, which of these three priority strategies is most appropriate for a specific disaster situation depends on the maximum rescue time allowed by the disaster.

Upon the occurrence of a disaster, emergency supplies should arrive at disaster areas with different severities in the shortest time. Therefore, it is of pivotal importance to plan and schedule appropriate processes. This paper first elaborates on the principle of ordered arrival of emergency supplies. Then, it establishes a multi-objective multi-constraint emergency material scheduling (EMS) model based on the principle of ordered arrival. Subsequently, a hybrid ant colony optimization (HACO) is proposed to solve EMS. The computational results for 15 multi-depot benchmark instances are reported and the average error between HACO and the best known solution (BKS) is only 0.16% Then, real geological disasters from Hubei province in China are examined as a case study. Experimental results show that HACO performs better than non-dominated sorting genetic algorithm II (NSGA-II) and multi-objective ant colony algorithm (MOACO) in the case study and benchmark instances.

Direct methanol fuel cells (DMFCs) require high-performance electrocatalysts for utilization at the commercial scale. In this paper, a novel, high-efficiency electrocatalyst composed of silver-platinum hollow nanodendrites based on N doping graphene quantum dots (N-GQDs/AgPt HNDs), which were synthesized via an easy wet chemical method, for the methanol oxidation reaction (MOR) is demonstrated. The photomediated Ag/N-GQDs nanoparticles (Ag/N-GQDs NPs) were firstly prepared under the condition of visible light illumination (the central wavelength is 589 nm), and then galvanic replacement reaction occurred between PtCl62- and Ag nanoparticles to obtain the final product. The morphology of the catalyst exhibits a uniform hollow structure by transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscope (EDX). The effects of the different mole ratio of Ag/Pt on the catalytic activity have been studied by cyclic voltammetry (CV) and chronoamperometry (CA). Under the optimal conditions, N-GQDs/AgPt HNDs show the excellent electrocatalytic activity of 2207.6 mA mgPt−1 towards MOR, which is about 21-fold higher than that of the commercial Pt/C. Interestingly, the photomediated Ag/N-GQDs NPs also caused the N-GQDs/AgPt HNDs catalysts to display a 1.7-fold enhancement in catalytic activity compared to that of the untreated Ag/N-GQDs NPs. Moreover, the CO tolerance and stability of the catalysts for MOR are also greatly improved. The present approach would provide an environment-friendly and valuable way to prepare multi-component catalysts with hollow nanostructures.

In order to make the bulk metallic glass (BMG) better used in micro electro mechanical system (MEMS), the rheological behavior of (Zr0.6336Cu0.1452Ni0.1012Al0.12)99.4Y0.6 BMG in the supercooled liquid phase region (SCLR) was studied, and the thermal processing map and the thermoplastic forming map were constructed in this paper. The Time-Temperature-Transformation (TTT) curve was established according to the crystallization incubation time of (Zr0.6336Cu0.1452Ni0.1012Al0.12)99.4Y0.6 BMG at different temperatures in the SCLR, which provided a theoretical basis for the time and temperature selection of thermal forming. Furthermore, the results show that the flow stress and viscosity coefficient of the BMG in the SCLR are strongly dependent on temperature and strain rate. The flow stress tends to decrease with the increase of temperature and the decrease of strain rate. When the temperature is 703 K with the strain rate of 5 × 10−4 s−1, the flow stress value is only 5 MPa. Meanwhile, the viscosity coefficient of the alloy remain approximately constant at 703 K, showing Newtonian fluid characteristic. It can be concluded that the alloy has excellent thermal processing property and thermoplastic forming (TPF) ability at temperature of 698–703 K, and thermoplastic forming ability is less affected by the strain rate within this temperature range.

Modification of cellulose homogeneously by graft copolymerization via grafting-from or grafting-to approaches is an attractive and versatile way to impart specific properties onto this promising renewable material. The grafting efficiency is greatly influenced by the solvent and catalyst used during this process. In this study, cellulose-graft-poly ( l -lactic acid) (C-g-PLLA) was prepared by ring opening polymerization of l -lactide (LA) (grafting-from) and transesterification of PLLA (grafting-to) with cellulose dissolved in CO2 switchable solvent. The impact of the presence of 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU) was then elucidated by comparing the grafting efficiency of the process with or without adding extra amount of this organic superbase. Results showed that without adding extra DBU, the grafting efficiency increased with an increase in concentration of grafting agents (LA or PLLA). However, when extra DBU was added, the grafting efficiency decreased with increased levels of DBU. These results indicate that the DBU protonated by the hydroxyl group from cellulose participated in the dissolution of cellulose after capture of CO2 in the switchable solvent, and played a role in the graft copolymerization to produce C-g-PLLA. On the other hand, the free DBU that was unprotonated displayed an antagonistic effect towards grafting copolymerization. Detailed graft copolymerization pathways and related modes of action were then considered in attempt to provide new insight into the role of CO2 switchable solvent for cellulose modification by ROP or transesterification.

Background Abnormal lipid metabolism has been reported in patients with idiopathic pulmonary arterial hypertension (IPAH); however, the prognostic value of plasma free fatty acids (FFAs) for these patients is unclear. The present study aimed to determine whether FFA can play a role in predicting the survival of patients with IPAH. Methods A total of 69 blood samples from patients with IPAH were subjected to liquid chromatography-mass spectrometry (LC-MS). According to the classification criteria for pulmonary hypertension in the European Society of Cardiology (ESC) guidelines, patients were divided into low-risk, intermediate-risk, and high-risk groups. The FFA expression levels of patients in the three groups were compared, and the indicators with significant differences were selected. Cox regression analysis was performed to examine the associations between survival and different factors. Receiver operator characteristic (ROC) curves were used to assess the predictive effect of plasma lipids in assessing patients' risk of morbidity, including area under the curve (AUC), sensitivity, specificity and the best cutoff value. Kaplan-Meier curves were used to predict survival. Results A total of 24 FFA molecules were detected in the patients with IPAH. Among them, FFA (20:4), FFA (20:5), FFA (22:5), FFA (22:6), FFA (24:0) and FFA (30:4) showed significant differences between the low-risk and the intermediate-risk or high-risk patients with IPAH. These six FFAs were significantly correlated with hemodynamic parameters. FFA (22:6), named docosahexaenoic acid (DHA), displayed significant negative correlations with World Health Organization functional classification (WHO FC), mean right atrial pressure (mRAP), and pulmonary vascular resistance (PVR), and significant positive correlations with 6-minute walking distance (6MWD) and cardiac index (CI). Cox regression analyses demonstrated that total bilirubin (TBIL) and DHA were independent risk factors for survival of IPAH. Receiver operating characteristic curve analysis revealed that DHA had a cut-off value of 77.55, which had a sensitivity of 96.7% and a specificity of 62.5% for predicting survival. Kaplan-Meier curve analysis showed that a lower level of DHA predicted a poor outcome in patients with IPAH. Conclusions Our study suggested that FFA levels were correlated with disease severity. Lower levels of DHA predict poor survival in patients with IPAH.

Ho3+/Yb3+ co-doped Ca3WO6 phosphors synthesized via a conventional solid-state reaction method and characterized structurally by X-ray diffraction analysis. For the investigation of particle size and the surface morphology of the prepared material the field emission scanning electron microscopy have been performed. No absorption band around 980 nm has been observed in the Ho3+ doped phosphors whereas a broad band around 980 nm in the Ho3+/Yb3+ co-doped phosphors corresponding to 2F5/2 → 2F7/2 absorption transition of Yb3+ ion has been detected. Up-conversion emission band have been observed in the visible region upon excitation with a 980 nm laser diode. The thermal stability of luminescence of Ca3WO6:Ho3+/Yb3+ was also investigated and the activated energy was deduced to be 0.173 eV, which shown good thermal stability. The study provides deep insights into the understanding of bidirectional energy transfer in UC mechanism, offering the possibility for applications in color displays and anti-counterfeiting techniques.

Two poplar lignin-carbohydrate complexes (LCCs), LCC-48 and LCC-72, were isolated at different milling times, 48 h and 72 h, respectively. A new hydrogel carrier was prepared from these LCCs in the presence of polyethylene glycol diglycidyl ether as the crosslinker for cell (human hepatocyte (L-02)) culture. The effects of the structure of LCC on the carrier were investigated. The FT-IR spectra indicate that the two LCC samples were composed of lignin and polysaccharide, and showed a typical LCC structure. The galactose contents of LCC-48 and LCC-72 were 3.02% and 5.67%, respectively. The results of cell culture show that a large number of hepatocytes adhered to the porous carriers. Hepatocytes grown on the LCC carriers outperformed the control group in every observed category, including cell proliferation rate and metabolic activity. These results indicate that poplar LCC might be a great potential precursor of biological carriers for human hepatocytes culture.

Turner's syndrome (TS) is the most common sex chromosome abnormality in females and characterized with short stature and ovarian dysgenesis. Patients with TS may also present many other physical diseases and mental disorders. In this case report, we present a 49-year-old woman with TS, who also met criteria for bipolar disorder, type 2 diabetes mellitus, and autoimmune hypothyroidism. The patient was admitted to the mental health center for depressive symptoms in 1991 and was misdiagnosed as hypopituitarism, which was not corrected until 2005 when her karyotype of 45, X/46, X, i(Xq) was identified. Due to the misdiagnosis and other specific reasons, the patient missed the optimal time for hormone replacement therapy.

Color tuning of Ca3WO6:Er3+/Yb3+ phosphors were prepared via high temperature solid method in this paper. The structure was investigated with X-ray diffraction (XRD) and the crystal morphology was observed through scanning electron microscopy (SEM). Visible up-conversion (UC) emissions were observed in green and red regions under the excitation of 980 nm diode laser. The luminescence study reveals strong 4S3/2 to 4I15/2 transition at 550 nm and strong 4F9/2 to 4I15/2 transition at 661 nm, respectively. In addition, it also can be observed that the green band is quenched and the red emission enhanced as the Yb3+ concentration increases. In consequence, the CIE coordinates changed from (0.30, 0.65) in the green region to (0.61, 0.38) in the red region at different Er3+/Yb3+ concentration. Thus, the tuning properties of Ca3WO6:Er3+/Yb3+ phosphors suggest that they could be good candidates for applications in lighting.

D 3h symmetric hexa-peri-hexabenzocoronene substituted by three carboxylic acid groups (HBC-COOH) was synthesized. HBC-COOH formed a rigid two-dimensional (2D) honeycomb network at a solid–liquid interface via intermolecular hydrogen bonding interactions. Guest molecules such as coronene can fill the cavities of this porous 2D network.

Two star-shaped molecules with benzene core and three naphthalene diimide (NDI) side arms were facilely prepared by two-step imidization reaction from the 1,4,5,8-naphthalenetetracarboxylic dianhydride. Two compounds showed the similar UV–vis absorption band as well as NDI. It was found that they displayed bathochromic shift of their UV–vis absorption and emission spectra in film compared with that in solution, ascribing to the aggregation between molecules in the solid state. Reversible reduction process was observed by cyclic voltammetry and low lying LUMO energy levels (−3.83 eV for 1a, −3.87 eV for 1b) were deduced, which suggest that these two compounds possessed good electron-acceptor property and can be used as potential n-type materials.

Platelet-derived growth factor receptor α (PDGFRα) is considered as a promising target for the treatment of fibrotic diseases. In this study, two types of pharmacophore model, which generated by ligand-based and receptor-based method, were put forward to identify novel chemical entities as PDGFRα inhibitors. It was found that some pharmacophore characteristics established by the two approaches overlap each other. In order to elucidate detailed interactions, representative molecules were selected to predict the conformations and binding modes of the molecules by molecular docking method. The calculation results of binding free energy illustrated that the van der Waals energy and nonpolar solvation were the most prominent contribution to the interactions between the inhibitors and PDGFRα. To further verify the accuracy of the docking results and the stability of the complexes system, the binding modes of two potent PDGFRα inhibitors were examined by 100 ns molecular dynamics simulations. Herein, we reported the basic structural requirements of PDGFRα inhibitors for the first time through molecular docking and molecular dynamics simulations. Subsequently, the two pharmacophore models were used for virtual screening to query potential active molecules from Food and Drug Administration approved database. The hit molecules here might provide additional scaffolds for further optimization of PDGFRα inhibitors.

Au-graphene quantum dots (GQDs)@Pt core-shell nanodendrites are synthesized through a two-step reduction approach, in which Au forms the core, GQDs form an intermediate layer and dendritic Pt forms the shell. Among the above synthesized catalysts, the GQDs can manipulate the binding of reaction intermediates on the Pt surface as well as assemble π-π * conjugate bonds, thus forming a dendritic Pt shell instead of a compact Pt shell. The obtained core-shell structure was characterized by transmission electron microscopy, energy-dispersive x-ray and x-ray photoelectron spectroscopy. The methanol electro-oxidation was investigated in alkaline media on the Au-GQDs@Pt modified electrode via cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy analysis. In particular, we discovered that Au-Pt assembled with GQDs could dramatically improve the activity and stability of the catalysts, owing to the synergistic effect raised by the GQDs, which exhibit prominent electron conductivity and great chemical/physical stability. It was also found that the Pt/Au mole ratios could control the Pt shell thickness, which significantly affected the catalytic methanol oxidation activity of the Au-GQDs@Pt nanodendrites. The Au-GQDs@Pt nanodendrites with optimum Pt/Au mole ratios of 1.0 exhibited a 2.5 times increase in electrocatalytic activity toward methanol oxidation compared with the commercial catalyst (Pt/C), and its CO tolerance was also greatly improved. The above results show that the Au-GQDs@Pt nanocatalysts have potential application prospects in direct methanol fuel cells.

A series of orange–red light-emitting Sm3+ activated Ba2ScNbO6 (x = 0.03, 0.05, 0.08, 0.10, 0.12, 0.14, and 0.16) phosphors were prepared through a traditional high temperature solid-state method. The properties of the samples were characterized by X-ray diffraction and scanning electron microscope. The emission and excitation spectrum, concentration quenching mechanism, and fluorescence attenuation of the phosphors were also investigated in detail. Upon excitation with near-Ultraviolent (407 nm), the emission spectra are composed of 564 nm, 598 nm and 645 nm emission peaks, corresponding to the different transitions of Sm3+ ions 4G5/2 → 6HJ (J = 5/2, 7/2, and 9/2), respectively. The strongest emission at 598 nm comes from the 4G5/2 → 6H7/2 transition of Sm3+, which produces bright orange–red emission. The optimum doping concentration of Sm3+ ion in Ba2ScNbO6 is 8 mol% and the critical transfer distance (Rc) of Sm3+ was calculated to be 20.97A. The thermal stability of Ba2ScNbO6:Sm3+ phosphor was tested by temperature-dependent emission spectroscopy. In addition, the Commission International deL’Eclairage the chromaticity coordinate of Ba2ScNbO6:0.08Sm3+ phosphor is (0.5435, 0.4514), which located in the orange reddish region. All the results show that the Ba2ScNbO6:xSm3+ phosphors can be used as orange–red light-emitting material for white light-emitting diodes.

In recent years, single-ion activated single-phase white phosphors played a crucial role in the field of near-ultraviolet (n-UV) white light-emitting diode (w-LED) illumination. In this work, a series of Na3Sc1–xSi2O7:xDy3+ phosphors was successfully prepared by high-temperature solid-state reaction method. The morphology and phase composition of the phosphors were confirmed by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Due to the 6H15/2 → 6P7/2 transition of Dy3+, the photoluminescence (PL) excitation spectrum of Na3Sc1–xSi2O7:xDy3+ exhibits a series of absorption peaks in the range of 250–450 nm and the strongest excitation peak is located at 349 nm. The PL spectra shows that the optimal doping concentration of Dy3+ is 0.13, which is controlled by dipole–dipole interaction according to the corresponding concentration quenching mechanism. The thermal stability of Na3Sc0.87Si2O7:0.13Dy3+ phosphor was investigated in detail and the compound has good thermal stability with activation energy of 0.198 eV. The decay time value of Na3Sc0.87Si2O7:0.13Dy3+ phosphor was calculated to be 0.4015 ms. The CIE chromaticity coordinates indicated that the phosphor produced warm white-light emission and testified the potential application of Na3ScSi2O7:Dy3+ as a new-style w-LEDs phosphor.

We demonstrate that a novel photodetector is constructed by CdS/poly( p-phenylene vinylene) (PPV) homogeneous hybrid nanowire arrays via a simple template-assisted electrochemical codeposition approach. Owing to the well-matched energy levels between CdS and PPV, the recombination of photogenerated electrons and holes in CdS/PPV hybrid nanowire arrays is greatly inhibited. It is found that the homogeneous hybrid nanowire arrays exhibit remarkably enhanced photoelectric response and the ON/OFF ratio by 17 times compared to the individual CdS component. More importantly, the CdS/PPV hybrid nanowire arrays are observed with significant spectral selectivity especially for green light under 545 nm. In addition, a straight linear relationship is obtained between the ON/OFF ratios and the illumination intensities, implying that the quantitative detection of illumination intensity can be achieved. The new as-prepared homogeneous hybrid organic/inorganic semiconductor nanowire arrays have a bright prospect for applications in high-sensitivity and high-speed green photodetectors.

In order to establish disease, many plant pathogens secrete so-called effector molecules to support host colonization, frequently through the modulation of host physiology. Accordingly, many effector molecules have been shown to be pivotal for microbial pathogenesis. Upon infection of its hosts, vascular wilt fungal pathogen Verticillium dahliae secretes effectors to enable host colonization. The aim of the research described in this thesis is to gain more insight into molecular mechanisms of V. dahliae pathogenesis, with a specific focus on the discovery of novel effectors that contribute to the establishment of V. dahliae infections on diverse host plants. Interestingly, we found that pathogenicity of V. dahliae on various plant hosts depends on relatively few effectors, and for some host species even on a single one. Such knowledge is essential for designing and developing novel and effective Verticillium wilt disease management strategies.

ObjectiveTo determine if plasma exosomal microRNAs (miRNAs) can predict survival in patients with idiopathic pulmonary arterial hypertension (IPAH).MethodsThe study enrolled patients with IPAH that underwent right heart catheterization. Plasma was collected and exosomal miRNAs were extracted. Exosomes were evaluated using transmission electron microscopy, Western blot analysis and particle size distribution analysis. MiRNAs were evaluated using a miRNA microarray and validated using real-time polymerase chain reaction.ResultsThis study included 12 patients with IPAH in the study group and 48 patients with IPAH in the validation group. The mean ± SD follow-up duration was 60.3 ± 35.4 months in the overall cohort. The levels of miR-596 were higher in the nonsurvivors compared with the survivors. The levels of miR-596 significantly correlated with survival time, mean right atrial pressure, pulmonary vascular resistance (PVR) and cardiac index. High levels of miR-596 and PVR were significantly associated with poor overall survival. Multivariate analysis demonstrated that exosomal miR-596 (hazard ratio [HR] = 2.119; 95% confidence interval [CI] 1.402, 3.203) and PVR (HR = 1.146; 95% CI 1.010, 1.300) were independent predictors of survival.ConclusionsHigh levels of plasma exosomal miR-596 were significantly associated with disease severity and poor prognosis of patients with IPAH.

At present, Pt-based catalysts with controllable compositions, architectures, and crystal facets are still the most prevalent materials for the electro-oxidation of methanol (MOR), which is a compelling reaction in proton exchange membrane fuel cells. Herein, based on graphene quantum dots (GQDs), we report a facial and environment-friendly approach to prepare the Au@GQDs@PtxPb core-shell nano-pompons for the MOR in alkaline solutions. It was noticed that among all the as-synthesized samples, Au@GQDs@Pt3.5Pb displays an admirable activity, which is as high as 15.14 A mg−1Pt and almost 38-fold higher than that of commercial Pt/C catalyst. And its resistance to poisoning species and long-term stability are also greatly improved. The improved performance for MOR might be attributed to the channel-rich structure of catalysts with the aid of GQDs, Au, and the electronic effect between Pt and Pb. The results indicate that the reasonable composition and structure of Au@GQDs@PtxPb exhibits efficient MOR, it could be a promising candidate for direct methanol fuel cells.

The catalytic degradation of organic wastewater by heterogeneous Fenton has attracted much attention in recent years. Compared with homogeneous Fenton, heterogeneous Fenton reaction has the advantages of wide pH range, low dissolved iron content after reaction, easy magnetic separation and good reusability. This paper mainly introduces the research progress of heterogeneous supported Fenton catalyst in the treatment of organic wastewater in recent years. In this paper, the degradation performance and recyclability of organic wastewater by catalysts are discussed, and the development direction of catalysts in the future is prospected.

Pitting corrosion occurs easily in metal pipelines containing corrosive media, which leads to premature failure of pipelines, oil, gas and water leakage, and increases the risk of environmental pollution. In this paper, the conditions of metal pitting, several nucleation mechanisms, growth and repassivation processes of metal metastable pitting are summarized. Corrosion electrochemical measurement technology can reflect the behavior characteristics of metal materials in the process of corrosion. The application of pitting of metal materials in the medium is introduced by using such electrochemical measurement techniques as polarization curve, electrochemical impedance spectrum, electrochemical noise and scanning electrochemical microscope.

In this work, we put forward a simple and green strategy to design and synthetic a highly efficient Au@GQDs@Pt3.5Bi nano-catalyst with a novel nanostructure composed of an Au@GQDs core and Pt3.5Bi alloy shell. This material showed outstanding catalytic capability for the oxidation of methanol (MOR) than that of the commercial Pt/C catalyst. The sequence of the mass activity was arranged to be commercial Pt/C (0.29 A mgPt−1) < Au@Pt3.5Bi (1.6 A mgPt−1) < Au@GQDs@Pt (1.81 A mgPt−1) < Au@GQDs@Pt3.5Bi (17.45 A mgPt−1). The outcomes ascribed to the unique core-shell structure with dendrites, interior electronic and synergistic effect with Bi and Pt. This work enlightens on the delicate proposal of novel core-shell nano-material for improving the electro-catalytic performance of MOR.

Urban land disturbance degrades physical, chemical, and biological soil properties by removing topsoil and compacting the remaining subsoil. Such practices create a soil environment that is unfavorable for vegetation establishment. A 3-year field study was conducted to compare the effects of various one-time compost application treatments on soil properties and re-vegetation of a disturbed soil. A disturbed urban soil received the following treatments: (1) inorganic fertilizer; (2) 2.5-cm-depth surface-applied compost; (3) 2.5-cm-depth incorporated compost; (4) 5.0-cm-depth incorporated compost; (5) inorganic fertilizer plus 0.6-cm compost blanket; and (6) inorganic fertilizer plus straw mat cover. The plots were seeded with a mixture of tall fescue Festuca arundinacea Shreb.: ‘Magellan,’ ‘Coronado Gold,’ ‘Regiment,’ and ‘Tomcat,’ perennial ryegrass Lolium perenne L. ‘Linn’, and Kentucky bluegrass Poa pratenis L. ‘Baron.’ Soil chemical and physical attributes and plant growth and quality parameter...

Since the reform and open-up, China’s marine fishery has developed rapidly, but it has also caused some practical contradictions. The focus is on the contradictions between overfishing and depleted fishery resources, and the continuous decline of marine fishery resources. The environmental destruction of marine resources and the sanitation and safety of marine aquatic products restrict the sustainable development of marine fisheries in the future. This article discusses the current situation of the development and utilization of marine fishery resources in China, and proposes some optimization measures for marine management in view of the current difficulties faced by marine fisheries.

A strategy for the synthesis of Au@N-CQDs@Pd three-layer core-shell nanoparticles without the use of any surfactant is proposed in this work. Herein, N-doped carbon quantum dots (N-CQDs) are used as the reducing agent, stabilizing agent, and shape-directing agent. The morphology and structure of the final product were characterized by Transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and X-ray powder diffraction (XRD). The electrocatalytic test indicates the as-synthesized Au@N-CQDs@Pd 20 exhibites excellent activity for methanol oxidation in alkaline media, which is approximately 6 times higher than commercial Pd/C. And its resistance to CO and stability are also greatly improved. This work provides a simple and straightforward approach to prepare bimetallic core-shell electrocatalyst by using CQDs with high catalytic activity for alkaline fuel cells.

Au-GQDs@AgPt Yolk-shell nanostructures with Au-GQDs yolk and AgPt alloy shell have been synthesized through a green wet chemical reduction method. In this process employed Au-GQDs as a yolk to obtain Au-GQDs@Ag nanoparticles (NPs), and then galvanic replacement reaction occurred between PtCl62- and Ag to fabricate Au-GQDs@AgPt Yolk-shell nanostructures. GQDs served as a structure-directing and dispersing agent to prepare homogeneous shell. The electrocatalytic performance of the as-synthesized Au-GQDs@AgPt Yolk-shell nanostructures for methanol oxidation reaction (MOR) is studied by cyclic voltammetry (CV) and chronoamperometry (CA). The catalyst has displayed excellent specific activity (33.20 mA cm−2), which is approximately 7 times higher than those of commercial Pt/C. And its CO tolerance and stability for MOR are also greatly improved. The results attribute to their particular structure (Yolk-shell nanostructures), electron effect with Ag and Pt, electron transport between GQDs and AgPt shell. The present strategy can provide an environment-friendly and valuable way to fabricate multicomponent nanostructures with Yolk-shell nanostructures.

With the development of the oil and gas field industry, the corrosion of metal materials in the H2S/CO2 environment has greatly restricted the development of the oil and gas industry. The corrosion of metal materials has gradually been paid attention to. The corrosion of steel under the H2S-CO2-Cl− system has been studied. Imminent. This paper briefly describes the corrosion and types of H2S and CO2 in steel for gathering pipelines, focusing on the reaction mechanism of corrosion, so as to achieve a more accurate grasp of corrosion laws and provide a theoretical basis for the development of new protection technologies. Keywords. H2S/CO2 environment; gathering pipeline steel; corrosion.

Aiming to support rural economic development, reduce the income gap between urban and rural residents, revitalize the rural economy, as well as encourage rural areas in all regions to carry out scientific, rational and sustainable development reforms, The Chinese government provides a certain amount of development approaches for rural planning and rural economic revitalization. In the setting of the The Chinese government’s rural strategy, design plans for rural complexes in various regions are emerging constantly. This article provides ideas for the planning and construction of pastoral complexes in other regions through the design ideas for the XiangFeng Pastoral complex in Guangzhou.

The 13-meter radio telescope monitor and control software, also called Client Graphics User Interface Library Tools (CGLT), is a set of graphical user interfaces provided to engineers and operators. It is a modular solution for monitoring and controlling the 13-meter radio telescope, which is a telescope under construction in Sheshan, Shanghai. Design philosophy, functionality and implementation of the software will be introduced in this article.

The recent advance of satellite technology has led to explosive growth of high-resolution remote sensing images in both quantity and quality. To address the challenges of high-resolution remote sensing images retrieval in both efficiency and accuracy, a distributed system architecture for satellite images retrieval by combining deep and traditional hand-crafted features is proposed in this paper. On one hand, to solve the problem of higher computational complexity and storage capacity, Hadoop framework is applied to manage satellite image data and to extract image features in parallel environment. On the other hand, deep features based on convolutional neural networks (CNNs) are extracted and combined with traditional features to overcome the limitations of hand-crafted features. Besides, object detection are integrated in the proposed system to realize accurate object locating at the time of retrieval. Experiments are carried on several challenging datasets to evaluate the performance of the proposed distributed system. Standard metrics like retrieval precision, recall and computing time under different configurations are compared and analyzed. Experimental results demonstrate that our system architecture is practical and feasible, both efficiency and accuracy can meet realistic demands.

In this work, the corrosion resistance of the welded joint and base metal of submarine X65 pipeline steel with ferrite plus bainite dual-phase microstructure was investigated by electrochemical and immersion tests. The corrosion product films were characterized using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and optical microscopy. To research the development of pitting corrosion in each zone, pitting diameter statistics were finished under optical microscopy and the forming mechanism of pitting induced by inclusion was analyzed. The experimental results proved that the corrosion resistance of the welded joint was better than that of the base metal, both from the general corrosion and pitting corrosion standpoint. In the welded joint, the weld metal has the best corrosion resistance, and then was the heat affected zone (HAZ). However, there was little difference between parent metal (near HAZ) and base metal (far HAZ) on the corrosion resistance. XRD and EDS analysis showed that the composition of the outer rust layer was mainly composed of Fe2O3, Fe3O4, FeOOH, and Fe(OH)3, and the inner layer was consisted of Fe2O3, Fe3O4, and a little FeOOH. Combined with the microstructure of the each zones, it can be concluded that the best corrosion resistance of the weld metal attributes to the refined grain size. Due to a creation of a galvanic effect between the ferrite and bainite, the dual-phase microstructure of the base metal and parent metal displayed weak corrosion resistance.

An approach for vehicle conflict analysis based on three-dimensional (3-D) vehicle detection is presented. Techniques for quantitative conflict measurements often use a point trajectory representation for vehicles. More accurate conflict measurement can be facilitated with a region-based vehicle representation instead. This paper describes a computer vision approach for extracting vehicle trajectories from video sequences. The method relied on a fusion of background subtraction and feature-based tracking to provide a three-dimensional (3-D) cuboid representation of the vehicle. Standard conflict measures, including time to collision and postencroachment time, were computed with the use of the 3-D cuboid vehicle representations. The use of these conflict measures was demonstrated on a challenging data set of video footage. Results showed that the region-based representation could provide more precise calculation of traffic conflict indicators compared with approaches based on a point representation.