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关键词： internally circulating fluidized bed   solid circulation rate   Eulerian-Eulerian model   kinetic theory of granular flow  

摘要： In this paper, the hydrodynamic flow inside an internally circulating fluidized bed (ICFBG) was characterized using experimental and three-dimensional computational fluid dynamics (CFD) models. Eulerian-Eulerian model (EEM) incorporating the kinetic theory of granular flow was implemented in order to simulate the gas-solid flow. A full-scale plexiglass cold flow experimental model was built to verify simulation results prior to the fabrication of the gasifier. Six parameters were manipulated to achieve the optimum design geometry: fluidization flow rate of the draft tube (Q(dt)), aeration flow rate of the annulus (Q(an)), initial bed static height (H-bs), draft tube height (H-dt), draft tube diameter (D-dt), and orifice diameter (D-or). The investigated parameters showed strong effect on the particle flow characteristics in terms of the pressure difference (Delta p) and solid circulation rate (G(s)). The predicted results by simulation for the optimum case were in close agreement with experimental measurements with about 5% deviation. The results show that the ICFBG operated stably with the maximum G(s) value of 86.6 kg/h at Q(dt) of 350 LPM, Q(an) of 150 LPM, H-bs of 280 mm, H-dt of 320 mm, Ddt of 100 mm, and D-or of 20 mm.

摘要： Background: Lymphatic malformation is a congenital lymphatic disorder. Although a few lymphangiographic and lymphoscintigraphic studies of lymphatic malformation exist, its lymphatic flow has not been fully assessed, and a classification system has not yet been established. However, indocyanine green lymphography has been developed to safely provide a fine assessment of lymph flow in the treatment of lymphedema. In addition, indocyanine green lymphography has been shown to be helpful in detecting the lymphatic malformation inflow for the treatment of refractory microcystic type lymphatic malformation using the venous anastomosis technique. Therefore, the authors aimed to reveal the in vivo lymph flow around the lymphatic malformation using indocyanine green lymphography, and to design a classification system according to the observed patterns. Methods: Indocyanine green lymphography was performed in 20 sequential pediatric patients with lymphatic malformation (aged 11 months to 10 years). Most of the cases were intractable, with microcystic or mixed-type lymphatic malformation. Results: All patients successfully completed lymphography with clear observations. The flow patterns were classified into four types: type 1 had a strong detectable inflow;type 2 had multiple small observable inflows;type 3 had a superficial lymph flow over the lesion;and type 4 had a flow around the lymphatic malformation, without any connections to the lesion. Conclusion: The proposed classification system may aid in the further development of surgical treatments for lymphatic malformation.

关键词： quanta   Phase transtormations   Compressibility   particle-hole   Glass transition   Monte Carlo technique   Exponent   Bosons   gapless  

摘要： Systems of disordered interacting bosons with particle-hole symmetry can undergo a quantum phase transition between the superfluid phase and the Mott glass phase which is a gapless incompressible insulator. We employ large-scale Monte Carlo simulations of a two-dimensional site-diluted quantum rotor model to investigate the properties of the superfluid density and the compressibility at this transition. We find that both quantities feature power-law critical behavior with exponents governed by generalized Josephson relations.

关键词： Vibration gas-solid fluidized bed   Pressure signals   Energy transfer   Dynamics behavior  

摘要： The study explores the characteristics of non-linear fluidization of vibration gas-solid fluidized bed (VGFB) and the laws of wave energy transfer. A VGFB (phi 110 mm x 180 mm) with the -0.3 + 0.074 mm magnetite particle was adopted in the experiment. The Hilbert-Huang transform (HHT) analysis of the pressure signal was used to obtain the time-frequency-energy two-dimensional Hilbert-Huang spectrum of pressure fluctuation signals under different fluidized states, and this revealed that the pressure fluctuation signal was composed of complex inter- and intra-wave frequency modulation components, this verified the non-linearity and randomness of the pressure signal. The distribution of the empirical mode decompositions (IMFs) energy of pressure fluctuation signal under different operation conditions was analyzed, and the results indicated that the IMF4 energy increased with increases in the bubble size. Conversely, with decreases in the bubble size, the energy was gradually transferred from IMF4 to IMF3, this revealed that the energy distribution of IMF3 and IMF4 exhibited a good correspondence with the bubble phase behavior and was a quantitative reflection of the non-linear bed fluidization. Finally, the main frequency and energy of the pressure signal were used to describe the dynamic behavior of the VGFB under different fluidized states. The results indicated that the pressure fluctuation frequency of quasi-dispersive fluidization and bubbling fluidization were both lower than that of the frequency of turbulent fluidization. Additionally, the pressure signal energy of quasi-dispersive fluidization was the lowest, bubbling fluidization was intermediary, and turbulent fluidization was the highest. (C) 2018 Elsevier B.V. All rights reserved.

关键词： 载金黄铁矿   稀土与微量元素   成矿流体来源   蚀变岩型和石英脉型矿石   罗山金矿床   胶东  

摘要： 罗山金矿床是胶东玲珑金矿田最大的金矿床之一,同时发育蚀变岩型矿化和石英脉型矿化。本研究在系统的野外和镜下工作基础上,利用电感耦合等离子体质谱(ICP-MS)技术分析了载金黄铁矿的微量和稀土元素,对比了蚀变岩型和石英脉型矿石载金黄铁矿稀土和微量元素特征,探讨了成矿流体的性质与来源。黄铁矿稀土总含量较低,多呈较明显的"右倾"式稀土配分模式,总体表现出负Eu异常,基本无Ce异常; Hf/Sm、Th/La、Nb/La值均<1,推断成矿流体为富Cl的还原性流体。Co/Ni比值范围在0. 08～3. 77,平均值为1. 09; Co/Ni值以及Co、Ni、Bi、Cu和Zn含量均与变质热液型金矿平均含量相近; Y/Ho比值范围总体在21～32之间,与中国东部大陆地壳Y/Ho比值(20～35)基本重合;结合个别样品的弱正Eu异常以及前人的研究成果,推断成矿流体与变质热液类似,主要来源于古太平洋板块俯冲板片脱水和脱碳作用,且可能有长英质岩浆流体和地壳流体的混入。蚀变岩型和石英脉型矿石内的载金黄铁矿的稀土、微量元素组成没有明显区别,Y/Ho、Nb/Ta和Zr/Hf比值变化范围均很小,表明两类矿石的载金黄铁矿为同一期热液活动作用的产物。

关键词： 泥石流   危险性评价   函数赋值模型   模糊综合评判   最优组合赋权法  

摘要： 基于彭阳县丁家渠泥石流前期调查测绘,查明了泥石流的发育特征,分析了泥石流的形成条件,并对其易发程度进行打分综合评判,得出:该泥石流为沟谷降雨诱发型泥石流,易发程度为中等易发,目前正处于衰退期。构建了包括泥石流规模、发生频率、沟谷流域面积、主沟长度、流域相对高差、流域切割密度及不稳定沟床比例等7个指标的单沟泥石流危险度评价指标体系,采用关联度分析与层次分析法相结合的最优组合赋权法对函数赋值模型中的权重进行修正,并运用该模型对丁家渠泥石流进行危险度计算,为了验证该模型在研究区泥石流危险度评价的准确性,同时采用模糊综合评判法进行危险度计算,两种方法得出的危险度等级均为低度危险,与实地调查结果相符。

关键词： 表面张力   拉脱法   智能手机   蓝牙  

摘要： 对FD-NST-B型液体表面张力测量仪加装额外的蓝牙通讯模块,并利用智能手机的蓝牙功能,使实验仪器能够通过蓝牙连接到智能手机上;同时开发出了专门的手机实验软件对该实验仪器进行控制,通过手机实验软件完成仪器数据的采集,并把采集到的所有数据在手机屏幕进行绘图,只需要观察手机屏幕上数据曲线,就能快速地得到精确的实验数据.该手机实验软件克服了传统实验模式的缺点,能够排除人为因素的影响,减小实验的偶然误差,提高测量的精确度.

关键词： 满洲里   银铅锌矿床   流体特征   矿床成因  

摘要： 满洲周里位于蒙古东北部地区,北部和西部与俄罗斯接壤。它是生产有色金属和贵金属矿床的重要区域。目前发现的大型贵金属矿床包括:乌奴格吐山的大型铜钼矿床,甲乌拉地区的银铅储量很大,查干不拉银地区的银铅储量很大。,八大关中型的铜钼矿床、额仁陶勒盖的大型银矿床、头道井小型铜钼矿床、哈拉胜小型铅锌矿床、八八一小型铜钼矿床、大坝铜金银矿点、巴彦浩雷铜金银矿点等。研究区的主要矿物是银,铅,锌,铜和钼。该矿区主要由银熔岩型的铜型油田组成,位于低热量油田和银质油田。满洲矿的特点类似于蒙古城市楚巴和俄罗斯秋田州,形成了蒙古-鄂木银矿,铅锌,铜钼,金和铀矿化省。以查干矿床为例,研究了矿床的地质特征,分析了流体包裹体的类型,讨论了成矿流体的性质和矿床的成因。

关键词： 流函数   匀场线圈   目标场方法  

摘要： 目标场方法由Turner率先提出,到目前为止该方法成为匀场线圈设计的主流方法。为解决有限尺寸、满足磁场均匀度条件下的线圈耗能问题,提出基于目标场方法下的改进设计方法。采用在一定线性度误差范围内满足匀场条件,利用最小的储能条件约束来对电流密度进行估计,再通过流函数对电流密度离散得到线圈实际的绕线方式,并将该方法运用于磁共振成像系统中的匀场线圈设计中。系统设计的梯度线圈纯度为5%,目标成像区域半径为0.25m,对设计方法进行仿真结果显示,提出的方法与理想磁场值得到较好的吻合,满足设计要求。

关键词： 大理石纹   表面活性剂   表面张力   油性颜料  

摘要： 在田野或山间,望着那层叠的山峰、潺潺的流水、翻卷的白云……只要用心的话,眼前都是美景,可谓美不胜收。大自然是美的,看到心动时,我们不禁想用相机或画笔记录下这些美妙的景色。不会画画怎么办?别急,用实验的方法也能'描绘出'美的瞬间。要说美,花草树木是人们喜爱的品类。植物的花自不必说,那是美丽的集中表现。