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关键词： Alaska   Headwater streams   Biomass   Nitrogen   Watershed   Alder  

摘要： Riparian wetlands are dynamic components of landscapes. Located between uplands and aquatic environments, riparian habitats intercept sediments and nutrients before they enter aquatic environments. They are a source of organic matter and nutrients to aquatic systems, and they provide important habitat for animals, often serving as corridors for the movement of animals between habitats in fragmented landscapes. In this project, we focused on the structure and function of riparian wetlands associated with headwater streams in Alaska that serve as nursery habitats for juvenile salmonids. We asked whether or not the structure and function of headwater wetlands differed between watersheds with and without nitrogen-fixing Alder (Alnus spp.). We found that the aboveground biomass of riparian vegetation was higher in the watershed with Alder, but the largest differences were in the litter layer and belowground where vegetation in the watershed with no Alder had significantly higher root biomass. Interstitial water chemistry also differed between the study sites with significantly higher inorganic N and significantly different characteristics of colored dissolved organic matter at the site with Alder on the watershed. The biomass of litter that hung over the creek bank was less at the site with Alder on the watershed and an in situ decomposition experiment showed significant differences between the two systems. Results of the research demonstrates that watershed characteristics can impact the ecology of headwater streams in ways that had not been previously recognized. (C) 2017 The Author(s). Published by Elsevier B.V.

关键词： erythroid CD71   flow cytometry scoring system   mast cell   Myelodysplastic syndrome   rare events  

摘要： Introduction: We created a simple and effective flow cytometry scoring system (FCSS) for suspected Myelodysplastic syndromes (MDS) samples and evaluated its diagnostic and prognostic potential. Methods: Besides evaluating the four parameters suggested by Ogata, we investigated erythroid precursors and mast cells. We evaluated the six-parameter FCSS in a four-color setting (test cohort: 51 patients;25 controls), then we implemented it into an eight-color setting and tested it on a validation cohort of patients with MDS (n=31). Results: When we compared MDS cases to non-MDS samples in the test cohort, we detected significant differences regarding not only the four major parameters but also two additional ones, namely CD71 rCV% of erythroid precursors (P=.004) and mast cell percentage (MC%) (P=.001). The utilization of the modified six-parameter FCSS provided high sensitivity and specificity both in the four color (84% and 80%, respectively) and in the eight color (81% and 100%, respectively) setting, with an excellent discriminative power between MDS and non-MDS samples. Furthermore, we found significant difference in event-free survival between the risk groups based on the modified six-parameter FCSS (P=.001). Conclusion: We evaluated and validated a single-tube flow cytometric procedure for a simple six-parameter FCSS which has not only high diagnostic but also prognostic power.

关键词： circulating fluidized bed   post-combustion   NOx   emission  

摘要： The combustion and NOx emission characteristics of low rank coal have been investigated in a circulating fluidized bed test plat, which was composed of a circulating fluidized bed (CFB) and post-combustion chamber (PCC). The effects of the air stoichiometric ratio in the circulating fluidized bed furnace and air arrangement in the post-combustion chamber were studied. In the optimized experimental condition, with the air stoichiometric ratio in the CFB ((CFB)) at 0.963, and post-combustion air (PCA) injected into the PCC using ports PCA1 and PCA3, the NOx emission was reduced to 48.7 mg/m(3). The conversion of the fuel-nitrogen in the coal into NOx did not occur under the reducing atmosphere in the circulating fluidized bed furnace. The final quantity of NOx generated from the combustion in the PCC was formed from gaseous HCN and residual nitrogen in fly ash, which flowed with flue gas from the CFB furnace. Enhancing the burnout fraction of coal in the CFB and using the air arrangement in the PCC could effectively reduce the final emission of NOx.

关键词： Electrochemistry   Reaction products   Alloys   Oxidation   Probes  

摘要： Corrosion experiments were conducted in a 0.4 T/D circulating fluidized bed (CFB) test rig with the high-sodium high-chlorine lignite as fuel to investigate the corrosion phenomena and mechanisms through the air-cooled probes in furnace and tails, respectively. Three alloy materials involving four metal elements (Al, Cr, Ni, and Fe) were used to compare their anticorrosion characteristics with the thermodynamic equilibrium calculation software Factsage 6.1 as an auxiliary tool. Experimental results indicate that the probes exposed to the high-temperature flue gas in the furnace suffered severe corrosion, which was primarily caused by gaseous corrosive media, including HCl (g), NaCl (g), and Cl-2 (g), while the probes in tails underwent the almost negligible corrosion arising from the deposited NaCl crystal on the top surface of the probe. The protective oxidation scale formed on the outer surface of alloy was the key to corrosion resistance rather than the internal metal with high quality. Despite different alloy elements matching different corrosive environments for its optimal anticorrosion, the Al2O3 was found most effective to resist the chlorine-induced corrosion in this study. In accordance with the Gibbs free-energy change (Delta G) of corrosion reactions, the increasing temperature failed to reduce the difficulty of corrosion in essence. The accelerated corrosion at a higher temperature was mainly ascribed to the improvement of the diffusion of the gaseous corrosive species and gaseous reaction products (metal chlorides). At a low-level wall temperature, to a certain extent the influence of gas temperature and alloy materials on corrosion can be ignored.

关键词： Fractional Brownian motion   stochastic boundary condition   density of the solution  

摘要： We study the existence and regularity of the density for the solution u(t, x) (with fixed t > 0 and x is an element of D) of the heat equation in a bounded domain D subset of R-d driven by a stochastic inhomogeneous Neumann boundary condition with stochastic term. The stochastic perturbation is given by a fractional Brownian motion process. Under suitable regularity assumptions on the coefficients, by means of tools from the Malliavin calculus, we prove that the law of the solution has a smooth density with respect to the Lebesgue measure in R.

关键词： H2AX   phospho-histone H3   p53   p21   genotoxicity  

摘要： Regulatory in vitro genotoxicity testing exhibits shortcomings in specificity and mode of action (MoA) information. Thus, the aim of this work was to evaluate the performance of the novel MultiFlow (R) assay composed of mechanistic biomarkers quantified in TK6 cells after treatment (4 and 24 hr): gamma H2AX (DNA double strand breaks), phosphorylated H3 (mitotic cells), translocated p53 (genotoxicity), and cleaved PARP1 (apoptosis). A reference dataset of 31 compounds with well-established MoA was studied using the MicroFlow (R) micronucleus assay. A positive call was raised following the earlier published criteria from Litron Laboratories. In the light of our data, these evaluation criteria should probably be adjusted since only 8/11 (73%) nongenotoxicants and 18/20 (90%) genotoxicants were correctly identified. Moreover, there is a need for new in vitro tools to delineate the predominant MoA as in the MicroFlow (R) assay only 5/9 (56%) aneugens and 4/11 (36%) clastogens were correctly classified. In contrast, the MultiFlow (R) assay provides more in-depth information about the MoA and therefore reliably discriminates clastogens, aneugens, and nongenotoxicants. By using a labspecific, practical threshold for the aforementioned biomarkers, 10/11 (91%) nongenotoxicants and 19/20 genotoxicants (95%), 9/11 (82%) clastogens, and 8/9 (89%) aneugens were correctly categorized, suggesting a clear improvement over the MicroFlow (R). Furthermore, the MultiFlow markers were benchmarked against established methods to assess the validity of the data. Altogether, these findings demonstrated good agreement between the MultiFlow (R) assay and the benchmarking methods. Finally, p21 may improve class discrimination given the correct identification of 4/4 (100%) aneugens and 2/5 (40%) clastogens. (C) 2017 Wiley Periodicals, Inc.

关键词： gasification   CFB gene   Slagging   Circulating fluidised beds   Gating and risering   charge bank  

摘要： Zhundong coal (ZDc) with a large reserve is faced with severe slagging and fouling during combustion in pulverized coal furnaces because of its high Na content. Due to the low-temperature reaction characteristics of a circulating fluidized bed (CFB), the ash-related problems might be alleviated when ZDc is used as fuel in a CFB. In this study, the slagging and fouling characteristics of three types of ZDc were tested in a 0.4 t/d CFB test system. The influences of three aspects including reaction temperature, reaction atmosphere, and coal property were studied in order to realize the utilization of ZDc in the CFB. Experimental results indicate that slagging and fouling still occurred in the CFB. During gasification, ZDc displayed slagging behaviors in the riser, which was closely related to the used bed material of quartz sand. The slagging degree was increased with the rise of reaction temperature. In different reaction atmospheres, the migration and transformation behaviors of Na differed, which further contributed to the slagging in the riser during gasification and fouling on tail heating surfaces during combustion, respectively. Besides, the Na content and occurrence mode in ZDc greatly impacted slagging. For the used three kinds of ZDc, their slagging tendencies obeyed the order of ZDc-3 > ZDc-1 > ZDc-2.

关键词： People flow   Symbolic trajectory   Movement pattern   Graph visualization  

摘要： People flow information brings us useful knowledge in various industrial and social fields including traffic, disaster prevention, and marketing. However, it is still an open problem to develop effective people flow analysis techniques. We considered compression and data mining techniques are especially important for analysis and visualization of large-scale people flow datasets. This paper presents a visualization method for large-scale people flow dataset featuring compression and data mining techniques. This method firstly compresses the people flow datasets using UniversaISAX, an extended method of SAX (Symbolic Aggregate Approximation). Next, we apply algorithms inspired by natural language processing to extract movement patterns and classify walking routes. After this process, users can interactively observe trajectories and extracted features such as congestions and popular walking routes using a visualization tool. We had experiments of classifying and visualizing walking routes using two types of people flow dataset recorded at an exhibition and a corridor applying our method. The results allow us to discover characteristic movements such as stopping in front of particular exhibits, or persons who passed same places but walked at different speeds. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Transfer function   Convolution   Unsteady heat transfer   Heat exchanger   Conduction and advection   Conjugate heat transfer  

摘要： Transient conjugate heat transfer (advection and diffusion) inside a heterogeneous physical system composed of solids and flowing fluids is considered here. Starting from a steady state initial temperature field, a single separable thermal excitation (thermal power or temperature difference) is activated. The heat equation as well as its associated boundary and interface conditions are assumed to be linear with time independent coefficients: there is no time nor temperature dependence of the thermophysical properties and velocity fields of both solids and fluids present in the system. In this case, it is shown that the temperature rise or heat flux response at any point of the system (or their space integrated quantities) is a convolution product between the intensity of the relative thermal excitation and a specific transfer function. In this work, a semi-analytical expression of the transfer function that takes into account the lateral heat losses, conduction and advection in the fluid as well as conduction in the solid walls (conjugate heat transfer) of a flat channel with a volumetric heat source (half heat exchanger) in transient state is derived. The analytical transfer function can be obtained for a simple geometry only. For complex geometries it can be identified experimentally. The analytical expression of the transfer function has been compared with that identified for a half-exchanger to verify the analytical expression of the transfer function and to show that this function can be identified experimentally. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： 径向吸气室   离心压缩机   流动损失   气流畸变  

摘要： 径向吸气室的内部流动损失及出口气流畸变是其影响离心压缩机性能的主要因素。为了进一步了解径向吸气室对离心压缩机性能影响的机理，本文针对上述因素对某工业用离心压缩机径向进气级开展了数值研究。研究表明，在该离心压缩机的正常运行区间内，径向吸气室的内部流动损失只会使整级性能下降，对下游叶轮和模型级的性能基本无影响；而吸气室出口的气流畸变不仅会使整级性能下降，更是导致叶轮及模型级性能下降的主要原因。希望通过本文的研究为径向吸气室的改进设计提供参考依据。