89 research outputs found

    Ferromagnetic InMnAs on InAs Prepared by Ion Implantation and Pulsed Laser Annealing

    Full text link
    Ferromagnetic InMnAs has been prepared by Mn ion implantation and pulsed laser annealing. The InMnAs layer reveals a saturated magnetization of 2.6 mu_B/Mn at 5 K and a perpendicular magnetic anisotropy. The Curie temperature is determined to be 46 K, which is higher than those in previous reports with similar Mn concentrations. Ferromagnetism is further evidenced by the large magnetic circular dichroism.Comment: 9 pages, 3 figure

    A Sensor Network Data Compression Algorithm Based on Suboptimal Clustering and Virtual Landmark Routing Within Clusters

    Get PDF
    A kind of data compression algorithm for sensor networks based on suboptimal clustering and virtual landmark routing within clusters is proposed in this paper. Firstly, temporal redundancy existing in data obtained by the same node in sequential instants can be eliminated. Then sensor networks nodes will be clustered. Virtual node landmarks in clusters can be established based on cluster heads. Routing in clusters can be realized by combining a greedy algorithm and a flooding algorithm. Thirdly, a global structure tree based on cluster heads will be established. During the course of data transmissions from nodes to cluster heads and from cluster heads to sink, the spatial redundancy existing in the data will be eliminated. Only part of the raw data needs to be transmitted from nodes to sink, and all raw data can be recovered in the sink based on a compression code and part of the raw data. Consequently, node energy can be saved, largely because transmission of redundant data can be avoided. As a result the overall performance of the sensor network can obviously be improved

    Preparation of carbon nanotube/polyaniline nanofiber by electrospinning

    Get PDF
    AbstractPolyaniline (PANI) is one of the most promising conductive polymers for its cheap and abundant, ease of synthesis, high conductivity and good environmental stability. However the disadvantages, such as insolubility, difficulties in processing and poor mechanical property hinder its application. Carbon nanotube (CNT) was considered as an excellent reinforcing material for its excellent mechanical properties, such as high aspect ratio, high chemical and thermal stability and good conductivity. In this paper, the CNT/PANI composite was prepared from the CNT/aniline nanofiber oxidation, which was obtained by the electrospinning technique. The composite electrochemical performances were characterized by the cyclic voltammogram, galvanostatic charging/discharging and four-probe method. The CNT/PANI composite had excellent application foreground in electrochemical energy field due to large current response, high conductivity and specific capacity

    AIF Downregulation and Its Interaction with STK3 in Renal Cell Carcinoma

    Get PDF
    Apoptosis-inducing factor (AIF) plays a crucial role in caspase-independent programmed cell death by triggering chromatin condensation and DNA fragmentation. Therefore, it might be involved in cell homeostasis and tumor development. In this study, we report significant AIF downregulation in the majority of renal cell carcinomas (RCC). In a group of RCC specimens, 84% (43 out of 51) had AIF downregulation by immunohistochemistry stain. Additional 10 kidney tumors, including an oxyphilic adenoma, also had significant AIF downregulation by Northern blot analysis. The mechanisms of the AIF downregulation included both AIF deletion and its promoter methylation. Forced expression of AIF in RCC cell lines induced massive apoptosis. Further analysis revealed that AIF interacted with STK3, a known regulator of apoptosis, and enhanced its phosphorylation at Thr180. These results suggest that AIF downregulation is a common event in kidney tumor development. AIF loss may lead to decreased STK3 activity, defective apoptosis and malignant transformation

    Microstructure Characterization and Mechanical Properties of TiSi 2 -SiC-Ti 3 SiC 2 Composites Prepared by Spark Plasma Sintering

    Get PDF
    Dense TiSi 2 -SiC and TiSi 2 -SiC-Ti 3 SiC 2 composites in which SiC particles in 200-300 nm disperse, were reactively synthesized through spark plasma sintering (SPS) technique using TiC, Si, and C powders in micrometer as starting reactants. The phase constituents and microstructures of the samples were analyzed by X-ray diffraction, field emission scanning electron microscopy and transmission emission microscopy. The hardness, fracture toughness and bending strength of TiSi 2 -SiC and TiSi 2 -SiC-Ti 3 SiC 2 composites were tested at room temperature. The fracture toughness and bending strength of TiSi 2 -SiC-Ti 3 SiC 2 composites reach 5:4 AE 0:3 MPaÁm 1=2 and 700 AE 50 MPa, respectively. The factors leading to the improvement of the mechanical properties were discussed

    Analysis the drivers of environmental responsibility of Chinese auto manufacturing industry based on triple bottom line

    Get PDF
    The rapid increasing number of automobile products has brought great convenience to people’s living, but it has also caused serious environmental issues, waste of resources and energy shortage during its whole lifecycle. Corporate Environmental Responsibility (CER) refers to the company’s responsibility to avoid damage to the natural environment derived from its corporate social responsibility (CSR), and it plays an important role in solving resource and environmental problems. However, due to various internal and external reasons, it is difficult for the automobile manufacturing industry to find the key drivers for the implementation of CER. This research proposes a model framework that uses the fuzzy decision-making test and evaluation laboratory (fuzzy DEMATEL) method to analyze the drivers of CER from the perspective of the triple bottom line (TBL) of economy, environment and society. Firstly, the common drivers of CER are collected using literature review and questionnaire survey methods. Secondly, the key drivers are analyzed by using the fuzzy DEMATEL. Finally, the proposed approach was verified through a case study. The research results show that some effective measures to implement CER can be provided for the government, the automobile manufacturing industry and the public to promote sustainable development of Chinese Auto Manufacturing Industry (CAMI)

    Mixed Eucalyptus plantations in subtropical China enhance phosphorus accumulation and transformation in soil aggregates

    Get PDF
    IntroductionThe production of Eucalyptus, a principal economic tree genus in China, is faced with challenges related to soil phosphorus (P) limitations. In this study, we explore variations in phosphorus content, storage, and transformation in Eucalyptus forests. We hypothesize that mixed forests augment soil aggregate stability and P content and that microaggregates are pivotal in determining P differences between mixed and pure forests. Additionally, we posit that mixed forests foster P transformation, enhancing its efficacy in the soil. Current research on the distribution and transformation of soil total P (TP) and P fractions at the soil aggregate level is limited.MethodsIn this study, we selected soil from a Eucalyptus-Mytilaria laosensis Lecomte mixed forest, Eucalyptus-Erythrophleum fordii Oliv mixed forest, and pure Eucalyptus forest in Chongzuo County, Guangxi, China, as the research objects. Using a dry-sieving method, we divided the soil collected in situ from the 0–40 cm layer into aggregates of >2, 1–2, 0.25–1, and <0.25 mm particle sizes, measured the TP and P fractions (resin-extractable inorganic P, bicarbonate-extractable inorganic P, bicarbonate-extractable organic P, sodium hydroxide-extractable inorganic P, sodium hydroxide-extractable organic P, dilute hydrochloric acid-extractable P, concentrated hydrochloric acid extractable inorganic P, concentrated hydrochloric acid-extractable organic P and residue-P) in different aggregates, and used redundancy analysis and PLS SEM to reveal key factors affecting soil P accumulation and transformation.ResultsThe results showed that compared to pure Eucalyptus forests, mixed Eucalyptus forests significantly enhanced the stability of soil aggregates and the content and storage of phosphorus, especially the Eucalyptus-Mytilaria laosensis mixed forest. The content of total soil phosphorus and its fractions decreased with increasing aggregate particle size, while the opposite trend was observed for stored P, with aggregates <0.25 mm being the main fraction influencing soil phosphorus accumulation. The transformation process of P fractions was primarily constrained by dissolution rates, mineralization rates, biological activity, including the action of microbes, fungi, and plant–root interactions, and other factors.DiscussionMixed forests increased the transformation of phosphorus in soil aggregates, effectivel enhancing the availability of soil phosphorus. In summary, this study provides important evidence for the systematic management of subtropical artificia Eucalyptus forests and the sustainable utilization of soil resources

    Discrete element simulation of particle motion in ball mills based on similarity

    Get PDF
    Discrete element (DE) simulation of a ball mill with a large number of particles is challenging when each particle is considered. Similarity principle could be adopted to reduce the number of particles in a simulation whilst still maintaining the accurate flow behaviour of particles. This paper presents a scaling relationship between particle gravitational acceleration, mill diameter and mill rotational speed. A series of scaled simulations of particle motion with different mill diameters are carried out. Consistent motion of a single particle and multiple particles in ball mills with different diameters and rotational speeds verifies the proposed relationship, which could be an effective approach to reduce the size of simulations for ball mills

    A Meta-Analysis of Caspase 9 Polymorphisms in Promoter and Exon Sequence on Cancer Susceptibility

    Get PDF
    BACKGROUND: Caspases are important regulators and executioners in apoptosis pathway and have been defined as either tumor suppressors or oncogenes. Polymorphisms in promoter and exon of caspase 9 were shown to confer genetic susceptibility to multiple cancers, but the results were inconsistent. To accomplish a more precise estimation of the relationship, a meta-analysis was performed. METHODOLOGY/PRINCIPAL FINDINGS: We assessed published studies of the association between caspase 9 polymorphisms and cancer risk from nine studies with 5,528 subjects for rs4645978, six studies with 2,403 subjects for rs105276 and two studies for rs4645981. Overall meta-analysis indicated that no evidence of an association between rs4645978 and cancers was found. Through the stratified analysis, statistically significant reduced cancer risks were observed among Caucasians (AG vs AA: OR = 0.81, 95% CI = 0.66-0.99, P(heterogeneity) = 0.150 and the dominant model: OR = 0.86, 95% CI = 0.75-0.99, P(heterogeneity) = 0.290) and prostate cancer. As for rs105276, Ex5+32G>A polymorphism was found with protective effect in overall meta-analysis (AA vs GG: OR = 0.75, 95% CI = 0.60-0.92, P(heterogeneity) = 0.887; A vs G: OR = 0.85, 95% CI = 0.77-0.95, P(heterogeneity) = 0.739 and the recessive model: OR = 0.68, 95% CI = 0.56-0.82, P(heterogeneity) = 0.309) and Asians group. While for rs4645981, a statistically significant increase in risk of lung cancer was shown in Asians (T vs C: OR = 1.23, 95% CI = 1.07-1.42, P(heterogeneity) = 0.399 and the dominant model: OR = 1.22, 95% CI = 1.04-1.43, P(heterogeneity) = 0.660). CONCLUSIONS/SIGNIFICANCE: Our meta-analysis suggests that the caspase 9 rs4645978 most likely contributes to decreased susceptibility to cancer in Caucasians and prostate cancer. The A allele of rs105276 might be a protective factor for cancer, especially for Asians. However, it seems that rs4645981 confers increased susceptibility to lung cancer in Asians
    corecore