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101.
Abstract. In this paper, we propose a fully Bayesian approach to the special class of nonlinear time‐series models called the logistic smooth transition autoregressive (LSTAR) model. Initially, a Gibbs sampler is proposed for the LSTAR where the lag length, k, is kept fixed. Then, uncertainty about k is taken into account and a novel reversible jump Markov Chain Monte Carlo (RJMCMC) algorithm is proposed. We compared our RJMCMC algorithm with well‐known information criteria, such as the Akaikes? information criteria, the Bayesian information criteria (BIC) and the deviance information criteria. Our methodology is extensively studied against simulated and real‐time series.  相似文献   
102.
An existing differential mobility analyzer (DMA) of cylindrical electrodes and a novel DMA of rectangular plate electrodes are demonstrated for size fractionation of nanoparticles at high-aerosol flow rates in this work. The two DMAs are capable of delivering monodisperse size selected nanoparticles (SMPS σg < 1.1) at gas flow rates ranging from 200 slm to 500 slm. At an aerosol flow rate of 200 slm, the maximum attainable particle mean size is of about 20 nm for the cylindrical DMA and of nearly 50 nm for the rectangular plate DMA. The number concentration of the monodisperse nanoparticles delivered by the high-flow DMAs spans from 104 cm?3 to 106 cm?3 depending upon the particle mean size and particle size dispersion.

Copyright 2014 American Association for Aerosol Research  相似文献   

103.
The water repellency of soils with different texture under different types of plant cover was determined by applying the WDPT and MED methods to both whole samples and the following size fractions: 2-1, 1-0.5, 0.5-0.25, 0.25-0.05 and <0.05 mm. Based on the results, the soils under maize crop and grassland, which were mostly wettable in the whole samples, exhibited water repellency in the finest fraction (<0.05 mm) as a result of its higher organic carbon content. On the other hand, all fractions in the forest soils, which were extremely water repellent, contributed to the overall repellency; in any case, the MED test revealed that the finest fraction was strongly repellent in the forest soils as well.  相似文献   
104.
Changes in the molecular structure of synthetic cathinones has led to an increase in the number of novel emerging drugs in the illicit drug market at an unprecedented rate. Unfortunately, little is known about the neuropsychopharmacology of recently emerged halogen-substituted α-PVP derivatives. Thus, the aim of this study was to investigate the role of para- and meta-halogen (F-, Cl-, and Br-) substitutions on the in vitro, in silico, and in vivo effects of α-pyrrolidinopentiophenone (α-PVP) derivatives. HEK293 cells expressing the human dopamine or serotonin transporter (hDAT and hSERT) were used for the uptake inhibition and transporter affinity assays. Molecular docking was used to model the interaction mechanism against DAT. Swiss CD-1 mice were used for the horizontal locomotor activity, open field test, and conditioned place preference paradigm. All compounds demonstrated potent DA uptake inhibition and higher DAT selectivity than cocaine. Meta-substituted cathinones showed higher DAT/SERT ratios than their para- analogs, which correlates with an increased psychostimulant effect in vivo and with different meta- and para-in silico interactions at DAT. Moreover, all compounds induced rewarding and acute anxiogenic effects in mice. In conclusion, the present study demonstrates the role of meta- and para-halogen substitutions in the mechanism of action and provides the first evidence of the rewarding and anxiety-like properties of halogenated α-PVP derivatives.  相似文献   
105.
106.
We report the effect of covering an electrodeposited black cobalt absorber film with a Ti : Sn oxide film at various atomic ratios prepared by the sol–gel dip process. The resulting composite was characterized in its optical, structural and morphological properties. After thermal treatment at 400°C, the uncoated black cobalt film is oxidized and Co3O4 is formed. Samples covered with Ti : Sn films and thermally treated at the same temperature suffered lower oxidation maintaining in great extent the original metallic cobalt structure. The optical properties of the resulting material were affected by the presence of the Ti : Sn coating, and the best protective film obtained was a transparent Ti : Sn (8 : 2) atomic ratio oxide film, with a 210 nm thickness. This composite system exhibits an absorptance value of 0.91 and an emittance value of 0.34 after a 100 h, 400°C thermal treatment. A photothermal material composed of a layer of black cobalt and a protective oxide film coating seems then a promising solar energy absorber capable of withstanding high operating temperatures (400°C).  相似文献   
107.
The aim of this study was to evaluate the air quality of an indoor swimming pool, analyzing diurnal and seasonal variations in microbiological counts and chemical parameters. The results indicated that yeast and bacteria counts, as well as carbon dioxide (CO2), nitrogen oxides (NOx) and O3 concentrations, showed significant diurnal difference. On the other hand, temperature, relative humidity (R.H.), yeast counts and concentrations of CO2, particles, O3, toluene, and benzene showed seasonal differences. In addition, the relationship between indoor and outdoor air and the degree of correlation between the different parameters have been calculated, suggesting that CO2, fine particles and NOx would have indoor origin due to the human activity and secondary reactions favored by the chemical and environmental conditions of the swimming pool; while O3, benzene and toluene, would come from outside, mainly. The overall results indicated that indoor air quality (IAQ) in the swimming pool building was deficient by the high levels of CO2 and microorganisms, low temperatures, and high R.H., because frequently the limits established by the legislation were exceeded. This fact could be due to the poor ventilation and the inadequate operation of heating, ventilation, and air‐conditioning systems.  相似文献   
108.
正趁着春节假期,我到台北和高雄看望久别的姐妹们。虽是第一次来到宝岛,不过吃住都是在姐妹家中,这趟旅行倒像是回家一样,没什么违和感与陌生感,然而小新鲜却总是不断。刚下飞机时,看到几乎人人戴口罩,这吓了我一跳,其实那里空气真不错,没遇到过雾霾天。这是怎么回事呢?  相似文献   
109.
正尽管中国足球无缘本届俄罗斯世界杯,但中国制造和中国品牌已令人侧目、笑傲全球。中国企业为本届世界杯的赛事经济贡献巨大,这对谋求重塑声誉的国际足联(FIFA)来说,无异于雪中送炭;对中国企业而言,期望通过世界杯的聚集效应放大自身的品牌价值,借势在商业征途上纵横四海,并将足球梦复兴梦与中国梦实业梦的雄心壮志结合得更为实际。2010年,瓦瓦祖拉的塑料喇叭响彻南非,普天同庆的官方用球和国旗、假发、墨镜、望远  相似文献   
110.
The objective of this study was to determine the evolution of physicochemical and flow properties of a yoghurt‐type beverage partially replaced with a chickpea extract over a period of 22 days. From two chickpea extracts, Blanco Noroeste was selected for its higher protein content. Six yoghurt‐type formulations were prepared, stored at 4 °C and analysed on days 1, 8, 15 and 22. pH was 4.24–4.75, while brightness was 81.7–94.5. Flow properties of the yoghurt‐type exhibited a non‐Newtonian behaviour. From three formulations that underwent sensory evaluation, the 30:70 mix obtained the highest acceptation. This yoghurt‐type beverage exhibited characteristics similar to natural yoghurt.  相似文献   
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