219 research outputs found

    Remediation of Heavy Metal Contamination in Calcareous Soil by Washing with Reagents: A Column Washing

    Get PDF
    AbstractThis paper presents an evaluation of different dose of HCl and Na2EDTA for the removal of Cd and Pb contaminated calcareous soil in the column mode. The field soil contained high concentrations of DTPA-extractable Cd (12.82mg kg-1) and Pb (105.38mg kg-1). Both HCl and Na2EDTA were found to be effective on removing DTPA-extractable Cd, but low concentration of HCl was ineffective on removing DTPA-extractable Pb and the highest removal efficiency of DTPA-extractable Pb washed by optimal dose of Na2EDTA was only 45.39%. In order to effectively and economically remove both metals from the contaminated soil, a sequential use of the optimal dose of HCl followed by the optimal dose of Na2EDTA was tested and 87.3% and 73.2% removal efficiency were obtained for DTPA-extractable Cd and Pb, respectively. Compared to using single washing agent, the removal efficiencies of DTPA-extractable Cd and Pb for the sequential washing with HCl followed by Na2EDTA were increased more than 8.3% and 27.92%, respectively. Results of soil extractions experiments revealed that the predominant fraction of the removed Cd and Pb were Fe/Mn oxide fraction and carbonate fraction. Trace metals in leachate collected from sequential washing was successfully precipitated and the leachate was safe for discharge

    A New Architecture for Application-aware Cognitive Multihop Wireless Networks

    Get PDF
    In this article, we propose a new architecture for AC-MWN. Cognitive radio is a technique to adaptively use the spectrum so that the resource can be used more efficiently in a low-cost way. A multihop wireless network can be deployed quickly and flexibly without fixed infrastructure. In our proposed new architecture, we study backbone routing schemes with network cognition, and a routing scheme with network coding and spectrum adaptation. A testbed is implemented to test the proposed schemes for AC-MWN. In addition to basic measurements, we implement a video streaming application based on the proposed AC-MWN architecture using cognitive radios. Preliminary results demonstrate that the proposed AC-MWN is applicable, and is valuable for future low-cost and flexible communication networks

    Torque Curve Optimization of Ankle Push-Off in Walking Bipedal Robots Using Genetic Algorithm

    Get PDF
    From MDPI via Jisc Publications RouterHistory: accepted 2021-05-11, pub-electronic 2021-05-14Publication status: PublishedFunder: the project of National Key R&D Program of China; Grant(s): 2018YFC2001300, 51675222Funder: National Natural Science Foundation of China; Grant(s): 91848204, 91948302Ankle push-off occurs when muscle–tendon units about the ankle joint generate a burst of positive power at the end of stance phase in human walking. Ankle push-off mainly contributes to both leg swing and center of mass (CoM) acceleration. Humans use the amount of ankle push-off to induce speed changes. Thus, this study focuses on determining the faster walking speed and the lowest energy efficiency of biped robots by using ankle push-off. The real-time-space trajectory method is used to provide reference positions for the hip and knee joints. The torque curve during ankle push-off, composed of three quintic polynomial curves, is applied to the ankle joint. With the walking distance and the mechanical cost of transport (MCOT) as the optimization goals, the genetic algorithm (GA) is used to obtain the optimal torque curve during ankle push-off. The results show that the biped robot achieved a maximum speed of 1.3 m/s, and the ankle push-off occurs at 41.27−48.34% of the gait cycle. The MCOT of the bipedal robot corresponding to the high economy gait is 0.70, and the walking speed is 0.54 m/s. This study may further prompt the design of the ankle joint and identify the important implications of ankle push-off for biped robots

    Dynamic pricing optimization for commercial subcontracting power suppliers engaging demand response considering building virtual energy storage

    Get PDF
    Commercial buildings have abundant flexible energy resources for demand response (DR). The electricity price for tenants in the commercial building is generally issued by a subcontracting power supplier (SPS), and the tenants cannot directly interact with the energy retailer. Therefore, the incentive for tenants to participate in DR is insufficient, and their potential is not fully explored. To address these issues, this paper proposes a dynamic pricing method based on the Stackelberg game, helping tenants actively participate in DR. Then, with the optimized energy consumption of the tenants, a virtual energy storage model of the commercial building is constructed by aggregating the adjustable capabilities of flexible energy resources such as air-conditioning (AC) and electric vehicles (EVs) in the public area. Finally, simulation tests are conducted based on a real commercial building to demonstrate the effectiveness of the game-theoretic pricing approach and validate the role of virtual energy storage of the building in DR

    Anti-Inflammatory Effect of Feiyangchangweiyan Capsule on Rat Pelvic Inflammatory Disease through JNK/NF- κ

    Get PDF
    Objectives. In this study, we aimed to illustrate the preventive effect and possible mechanisms of Feiyangchangweiyan capsule (FYCWYC) on rat pelvic inflammatory disease (PID) model. Methods. To construct the rat PID model, upper genital tract was infected by multipathogen, and then drugs were orally administered for 8 days. The histological examination, immunohistochemical analysis, and ELISA were carried out. Furthermore, Western blotting was used to analyze the expression of Akt, MAPKs, NF-κB p65, and IκB-α in uterus. Results. As the results showed, infiltrations of neutrophils and lymphocytes in uterus were significantly suppressed, and IL-1β, IL-6, CXCL-1, and TNF-α were also reduced in a dose-dependent manner. We also found that FYCWYC inhibited apoptosis induced by infection. Furthermore, FYCWYC could block the infection-induced nuclear translocation of NF-κB. We found that FYCWYC treatment only decreased the phosphorylation of JNK induced by infection and had no effects on Akt and P38. Additional, the effects of SP600125, an inhibitor of phospho-JNK, were similar to the results of FYCWYC. Conclusions. Taken together, our results demonstrated that FYCWYC had anti-inflammatory effect in pathogen-induced PID model, and the mechanism might be through inhibiting NF-κB nuclear translocation which is mediated by JNK

    Pore-scale remaining oil distribution under different pore volume water injection based on CT technology

    Get PDF
    A water-injection experiment was performed on a water-wet reservoir core plug that was filled with brine first and then displaced by synthetic oil. A X-ray Computed Tomography was used to take snapshots of the process of oil-water displacement at predefined time intervals to characterize the distribution of remaining oil. The quasi-real time images were used to understand the pore-scale phase displacement mechanisms and the distributional pattern of the remaining oil. Four forms of the distributional patterns, i.e. network, porous, isolated and film shape, were observed and analyzed with respect to the injected pore volumes (PV). The results show that with the increased level of water injection, the volume of the oil phase continuously decreases, and the morphology of the oil phase changes from initial continuous network-like to film shape forms. At 15 PV, the network- like remaining oil disappears and transforms into isolated and film-like forms. The statistics of the volume for each form of the remaining oil show that the isolated blobs increase with increasing water injection, by contrast, the average volume of the remaining oil decreases with increasing water injection. The rate of volumetric changes is fast before 5 PV but slow in the later period.Cited as: Liu, Z., Yang, Y., Yao, J., et al. Pore-scale remaining oil distribution under different pore volume water injection based on CT technology. Advances in Geo-Energy Research, 2017, 1(3): 171-181, doi: 10.26804/ager.2017.03.0

    Comparative transcriptome profiling provides insights into plant salt tolerance in seashore paspalum (\u3ci\u3ePaspalum vaginatum\u3c/i\u3e)

    Get PDF
    Background Seashore paspalum (Paspalum vaginatum), a halophytic warm-seasoned perennial grass, is tolerant of many environmental stresses, especially salt stress. To investigate molecular mechanisms underlying salinity tolerance in seashore paspalum, physiological characteristics and global transcription profiles of highly (Supreme) and moderately (Parish) salinity-tolerant cultivars under normal and salt stressed conditions were analyzed. Results Physiological characterization comparing highly (Supreme) and moderately (Parish) salinity-tolerant cultivars revealed that Supreme’s higher salinity tolerance is associated with higher Na+ and Ca2+ accumulation under normal conditions and further increase of Na+ under salt-treated conditions (400 mM NaCl), possibly by vacuolar sequestration. Moreover, K+ retention under salt treatment occurs in both cultivars, suggesting that it may be a conserved mechanism for prevention of Na+ toxicity. We sequenced the transcriptome of the two cultivars under both normal and salt-treated conditions (400 mM NaCl) using RNA-seq. De novo assembly of about 153 million high-quality reads and identification of Open Reading Frames (ORFs) uncovered a total of 82,608 non-redundant unigenes, of which 3250 genes were identified as transcription factors (TFs). Gene Ontology (GO) annotation revealed the presence of genes involved in diverse cellular processes in seashore paspalum’s transcriptome. Differential expression analysis identified a total of 828 and 2222 genes that are responsive to high salinity for Supreme and Parish, respectively. “Oxidation-reduction process” and “nucleic acid binding” are significantly enriched GOs among differentially expressed genes in both cultivars under salt treatment. Interestingly, compared to Parish, a number of salt stress induced transcription factors are enriched and show higher abundance in Supreme under normal conditions, possibly due to enhanced Ca2+ signaling transduction out of Na+ accumulation, which may be another contributor to Supreme’s higher salinity tolerance. Conclusion Physiological and transcriptome analyses of seashore paspalum reveal major molecular underpinnings contributing to plant response to salt stress in this halophytic warm-seasoned perennial grass. The data obtained provide valuable molecular resources for functional studies and developing strategies to engineer plant salinity tolerance
    corecore