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关键词： Ag-Au-Cu合金   表面张力   Butler模型   Toop模型  

摘要： 表面张力对于材料而言是一种关键性的性质,该性能在液态金属和合金的成分设计领域有着十分重要的地位,其对铸造以及键合丝键合时金属凝固过程中表面是否开裂、焊接后焊接处的微观形貌有着决定性的影响。使用Butler模型和Toop模型分别计算金银铜及其对应二元合金在熔融状态下的表面张力并与实验值进行对比,从而为金银键合丝的成分设计起到一定的指导作用。结果表明:采用Butler模型和Toop模型计算出二元以及三元合金的表面张力与实验值相差较小。在1381K下,Ag-Au-Cu三元合金表面张力随Au和Cu含量变化介于0.89392~1.32471 N/m之间,表面张力随Ag或者Cu含量增加呈现单调减小或单调增大的趋势。

关键词： 岩子河铅锌矿   流体包裹体   成矿流体   斑岩型  

摘要： 随县岩子河铅锌矿赋存于桐柏杂岩的片麻状花岗岩中,成矿过程经历了5个阶段;流体包裹体主要有气液相包裹体、含有子矿物多相包裹体、含CO2三相包裹体、纯气相包裹体和纯液相包裹体5类;包裹体的演化分为5个阶段,从早阶段到晚阶段,温度—盐度逐步降低,1-3阶段主要为气液相包裹体、含有子矿物多相包裹体,为CO2-H2O-NaCl±CaCl2体系,4-5阶段主要为气液相包裹体,为H2O-NaCl体系;成矿流体来源于岩浆流体,晚期混有大气降水,流体沸腾是成矿的重要因素,大气降水的渗入是成矿的另一重要因素,成矿作用主要与2-3阶段流体沸腾和4阶段大气降水的渗入相关联,与大陆碰撞体制的浆控高温热液矿床特征一致,具斑岩型矿床的特征。

关键词： 致密油   微观孔隙结构   流体可动用性   高压压汞   核磁共振  

摘要： 为准确评价延长油田志定区块致密油储层微观孔隙结构特征及流体可动用规律,本文选取目标区块典型样品16个,开展高压压汞以及核磁共振结合高速离心测试。通过测试发现:目标储层孔隙分布基本呈单峰或者双峰分布,并且渗透率越大右峰越高或者右峰越向右移。孔隙基本全部分布于1μm以下,平均喉道处于0.4μm以下。亚微米级孔隙及纳米级孔隙占据了50%以上,渗透率贡献主要来自于亚微米级孔隙。储层T2谱根据形态分为3类,不同离心力作用主要对右峰产生影响,即流体动用主要来源于较大孔隙。志定区块约70%的流体赋存与纳米级孔隙,总可动流体处于35%以下,储层极难动用。孔隙致密是导致储层流体难以动用的根本因素。

关键词： Multiphase flow   Conductivity probe   Optical probe   Multisensor measurement   Data fusion   PCA   k-mean clustering  

摘要： Attempts have been made for identification and classification of regimes for upward air-water two-phase flow fusing the response from multiple sensors. A needle type conductivity probe and different combinations of optical probes have been employed. The statistical signatures of the signals have been used for identification of the type of flow and revealing some information regarding the interfacial structure. The signals have further been processed using Principal Component Analysis (PCA) and used to classify the flow regime by k-mean clustering algorithm. Classifications have been made using signals from different individual sensors as well as combining them. Finally, the performance of the predictions made by these sensor combinations have been made using confusion matrix. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Sewage sludge   Hydrothermal carbonization   Co-combustion   Fluidized bed  

摘要： The current study presents the experimental results investigating combustion characteristics of sewage sludge fuels (SS) reference to coal and wood pellet as the two typical base fuels. Two types of SS were produced by drying and hydrothermal carbonization technology. The composition analysis and the thermogravimetric analysis (TGA) showed that SS were highly volatile with low ignition temperature than coal and wood pellet. In the lab-scale bubbling fluidized bed experiments, the combustion gas composition and bed temperature were measured for the cases of single fuel and blended fuel. The morphology and the composition of fly ash collected at the cyclone were analyzed using particle size analyzer, ICP-OES, and SEM-EDS. In the single fuel cases, NOx and SO2 emission of SS were several times higher than the base fuels, but those could be reduced in the blend fuel cases while maintaining overall thermal input and bed temperature. The different size distribution and overall composition of fly ash for the single fuel cases became similar in the blend fuel cases. The change in the characteristics of fly ash was considered to be related to the distribution of mineral matters, such as Ca, K, and P in particular. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Imaging flow cytometry   label-free   stain-free   deep learning   machine learning   classification   white blood cells   leukocytes   eosinophils  

摘要： Imaging flow cytometry (IFC) produces up to 12 spectrally distinct, information-rich images of single cells at a throughput of 5,000 cells per second. Yet often, cell populations are still studied using manual gating, a technique that has several drawbacks, hence it would be advantageous to replace manual gating with an automated process. Ideally, this automated process would be based on stain-free measurements, as the currently used staining techniques are expensive and potentially confounding. These stain-free measurements originate from the brightfield and darkfield image channels, which capture transmitted and scattered light, respectively. To realize this automated, stain-free approach, advanced machine learning (ML) methods are required. Previous works have successfully tested this approach on cell cycle phase classification with both a classical ML approach based on manually engineered features, and a deep learning (DL) approach. In this work, we compare both approaches extensively on the problem of white blood cell classification. Four human whole blood samples were assayed on an ImageStream-X MK II imaging flow cytometer. Two samples were stained for the identification of eight white blood cell types, while two other sample sets were stained for the identification of resting and active eosinophils. For both data sets, four ML classifiers were evaluated on stain-free imagery with stratified 5-fold cross-validation. On the white blood cell data set, the best obtained results were 0.778 and 0.703 balanced accuracy for classical ML and DL, respectively. On the eosinophil data set, this was 0.871 and 0.856 balanced accuracy. We conclude that classifying cell types based on only stain-free images is possible with all four classifiers. Noteworthy, we also find that the DL approaches tested in this work do not outperform the approaches based on manually engineered features. (c) 2019 International Society for Advancement of Cytometry

关键词： Schrodinger equation   Cauchy problem   solution representation   Chernoff theorem  

摘要： In the paper we derive two formulas representing solutions of Cauchy problem for two Schrodinger equations: one-dimensional momentum space equation with polynomial potential, and multidimensional position space equation with locally square integrable potential. The first equation is a constant coefficients particular case of an evolution equation with derivatives of arbitrary high order and variable coefficients that do not change over time, this general equation is solved in the paper. We construct a family of translation operators in the space of square integrable functions and then use methods of functional analysis based on Chernoff product formula to prove that this family approximates the solution-giving semigroup. This leads us to some formulas that express the solution for Cauchy problem in terms of initial condition and coefficients of the equations studied.

关键词： Linear flow   Flow equivalence   Orbit equivalence   (uniform) core   Kronecker flow  

摘要： New elementary, self-contained proofs are presented for the topological and the smooth classification theorems of linear flows on finite-dimensional normed spaces. The arguments, and the examples that accompany them, highlight the fundamental roles of linearity and smoothness more clearly than does the existing literature.

关键词： Sun   cycles 23 and 24   flares   CMEs   proton events   geomagnetic indices  

摘要： Solar flare activity is characterized by different classification systems, both in optical and X-ray ranges. The most generally accepted classifications of solar flares describe important parameters of flares such as the maximum of brightness of the flare in the optical range - H alpha flare class (change from F to B), area of the flare in H alpha (change from S for areas less than 2 square degrees to 4 for areas more than 24.7 square degrees) and the maximum amplitude of the soft X-ray (SXR)-flux in the band 0.1-0.8 nm (F0.1-0.8max) - X-ray flares of classes from C to X. A new classification parameter of solar flares is proposed here - the X-ray index of flare XI, based on GOES measurements of solar radiation in the SXR-range. The XI-index has a clear physical interpretation associated with the total flare energy in the SXR-range. XI is easily calculated for each flare with the use of available GOES data. The XI-index can be used along with other geoeffective parameters of Solar activity to assess both flares and coronal mass ejections that are connected with them.

关键词： Liquid mixing   dispersion coefficient   solid-liquid fluidized bed   solid-liquid circulating fluidized bed   axial dispersion model  

摘要： Liquid phase axial mixing studies have been carried out in the novel solid-liquid circulating fluidized bed (SLCFB). The SLCFB primarily consists of a single multistage column (having an inner diameter of 100 mm i.d. and length of 1.40 m) which is divided into two sections wherein both the steps of utilization, namely loading (e.g., adsorption and catalytic reaction) and regeneration of solid phase, can be carried out simultaneously in continuous mode. Weak base anion exchange resin was used as the solid phase, whereas water as the fluidizing medium. The effects of physical properties of solid phase, superficial liquid velocity, and solid circulation rate on liquid phase axial dispersion coefficient were investigated. The dispersion coefficient increases monotonically with an increase in the size of solid particle, superficial liquid velocity, and solid circulation rate. The axial dispersion model (ADM) was used to model experimental residence time distribution (RTD) data. A good agreement was found between ADM predictions and the experimental measurements. A unified correlation has also been proposed to determine dispersion coefficient as a function of physical properties of solid and liquid phases, superficial liquid velocity, and solid circulation rate based on all previous and present experimental data on multistage SLCFB.