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关键词： C-H-O同位素   流体包裹体   成矿流体   邦铺   西藏  

摘要： 选取西藏冈底斯斑岩成矿带东段的邦铺矿床斑岩矿区2条勘探线上的11个钻孔,进行了详细的岩芯编录和矿物组合、脉体穿切关系研究,将该矿床内与斑岩成矿相关的脉体划分为A、B、D脉3种类型。通过对矽卡岩矿区的详细地表及平硐观察,发现了石榴子石、阳起石、绿帘石等一系列代表流体演化特征的矿物。邦铺矿床具有典型斑岩型矿床的蚀变分带特征,从中心向外依次表现为黑云母化-硅化-绢云母化-青磐岩化,泥化呈"补丁状"无规则分布在绢云母化和青磐岩化之上。矽卡岩化则以典型矽卡岩矿物的出现为特征。A脉中绝大多数包裹体均一温度为320~550℃,盐度主要集中在两个区间内,分别为17.0%~22.0%(气液两相包裹体)和30.8%~67.2%(含子晶包裹体);B脉中绝大多数包裹体均一温度为380~550℃,盐度主要集中在1.6%~10.1%、23.2%~24.5%(气液两相包裹体)和30.8%~67.2%(含子晶包裹体)3个区间内;D脉中绝大多数包裹体均一温度为213~450℃,盐度为7.3%~11.6%。流体包裹体研究表明,与斑岩成矿的相关流体具有从高温、高盐度向低温、低盐度演化的特征;形成A、B脉的流体发生了强烈的沸腾作用,由此导致的压力波动是Mo、Cu沉淀的主要原因。16件与斑岩成矿相关的石英δDV-SMOW=-107.1‰^-185.8‰,δ18OV-SMOW=9.5‰~14.5‰;15件与矽卡岩成矿相关的石榴子石、绿帘石、石英及方解石δDV-SMOW=-184.7‰^-126‰,δ18OV-SMOW=3.9‰~12.9‰;4件斑岩成矿后期的方解石δ18OV-SMOW=-1.6‰~10.4‰,δCV-PDB=-6.5‰^-3.4‰;6件与矽卡岩成矿相关的方解石δ18OV-SMOW=1.8‰~11.9‰,δCV-PDB=-5.1‰~4.6‰。C_H_O同位素分析数据表明,邦铺整个斑岩-矽卡岩成矿系统流体主要经历了岩浆脱水去气和大气降水加入这两大地质过程。

关键词： 腰果酚   酚醛树脂聚醚   破乳剂   界面张力   表面张力  

摘要： 以腰果酚和甲醛为原料合成腰果酚醛树脂起始剂,再与环氧乙烷(EO)和环氧丙烷(PO)聚合,合成腰果酚醛树脂嵌段聚醚破乳剂(CPFE)。采用表面张力法测定了CPFE的临界胶束浓度(cmc)为80mg/L,对应的表面张力值(γcmc)为17.38mN/m。采用旋滴法测定了CPFE的油-水界面张力,考察了CPFE质量浓度和温度对油-水界面张力的影响。结果表明,随着CPFE质量浓度增加,油-水界面张力显著下降;随着温度升高,CPFE的界面活性下降,表明CPFE适合在低温环境下使用。采用单滴法测定了油滴破裂速率常数k随CPFE质量浓度的增加而增大。

关键词： 油田化学   丙烯酰胺   大分子单体   二元复合体系   增黏性能   表观黏度   表面张力  

摘要： 将大单体4-乙烯苄基辛烷基酚聚氧乙烯(18)醚、丙烯酰胺和2-丙烯酰胺基-2-甲基丙磺酸钠共聚合成接枝丙烯酰胺共聚物(branched acrylamide-based copolymer,PAE),然后将具有表面活性的PAE分别与4种表面活性剂复合,获得二元复合驱油体系.研究各表面活性剂对这些二元复合驱油体系的表观黏度和表面张力的影响,与油田常用的部分水解聚丙烯酰胺-表面活性剂二元复合驱油体系相比,这些体系可提高驱油剂的增黏性和表面活性,改善驱油过程中的色谱分离效应.在阴离子表面活性剂(十二烷基硫酸钠和十二烷基苯磺酸钠(sodium dodecyl benzene sulfonate,SDBS)、阳离子表面活性剂(十六烷基三甲基溴化铵)和非离子表面活性剂(聚氧乙烯(20)山梨醇酐单硬脂酸酯)中,微量SDBS对聚合物体系溶液黏度提高幅度最大,且能明显降低体系的表面张力,当SDBS浓度为0.6 mmol/L时,PAE二元复合驱油体系(含5.0 g/L Na Cl,1.2 g/L PAE)的表观黏度可从243 m Pa·s上升到732 m Pa·s.

关键词： METABOLISM   PHENOTYPE   STABLE isotopes   BIOCHEMISTRY   TAXONOMY  

摘要： Metabolic reaction rates (fluxes) contribute fundamentally to our understanding of metabolic phenotypes and mechanisms of cellular regulation. Stable isotope-based fluxomics integrates experimental data with biochemical networks and mathematical modeling to ‘measure’ the in vivo fluxes within an organism that are not directly observable. In recent years, 13 C fluxomics has evolved into a technology with great experimental, analytical, and mathematical diversity. This review aims at establishing a unified taxonomy by means of which the various fluxomics methods can be compared to each other. By linking the developed modeling approaches to recent studies, their challenges and opportunities are put into perspective. The proposed classification serves as a guide for scientific ‘travelers’ who are striving to resolve research questions with the currently available 13 C fluxomics toolset. [ABSTRACT FROM AUTHOR]

关键词： Wave energy prediction   Ordinal classification   Multi-class classification   Significant wave height   Flux of energy   Wave energy converters   REGRESSION   PREDICTION   WIND   CLASSIFICATION   TECHNOLOGIES   REANALYSIS  

摘要： In this paper, the performance of different ordinal and nominal multi-class classifiers is evaluated, in a problem of wave energy range prediction using meteorological variables from numerical models. This prediction could be used in problems of wave energy conversion in renewable and sustainable systems for energy supply. Specifically, the work is focused on ordinal classifiers, that have provided excellent performance in previous applications. The proposed techniques are novel with respect to alternative classification and regression techniques used up to date, the former not considering the order relation between classes in a multi-class problem and the latter needing, in general, more complex models. Another important novelty of the paper is to consider meteorological variables from numerical models as inputs of the classifiers, which has not been done before, to our knowledge, in this context. For this, a data matching is carried out between meteorological data, obtained from NCEP/NCAR Reanalysis Project in four points around the two buoys subjected to study (a buoy in the Gulf of Alaska and another one in the Southeast of United States), and the wave height or wave period collected by sensors in each buoy. Using this matching, the problem is tackled as an ordinal multi-class classification problem and the objective is to predict the range of height of the wave produced in each buoy and the range of energy flux generated. The classifiers to be compared and the model proposed are fully evaluated in both buoys. The results obtained are promising, showing an acceptable reconstruction by ordinal methods with respect to nominal ones in terms of wave height and energy flux. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： DRYER   SIMULATION   HEAT   BATCH   TEMPERATURE   KINETICS   TRAY  

摘要： In this study fluidized bed drying characteristics of ginger have been investigated. The effects of the fluidizing air temperature, velocity, humidity and bed height on the drying performance of ginger slices have been found. The experimental moisture loss data of ginger slices has been fitted to the eight thin layer drying models. Two-term model drying model has shown a better fit to the experimental data with R2 of 0.998 as compared to others.

关键词： Fluidized-bed drying   Vacuum drying   Organic solvent injection   Drying rate   Falling drying rate   SUPERHEATED STEAM   POROUS MATERIALS   MASS-TRANSFER   SOLIDS   CARROTS   HEAT  

摘要： We tested a new fluidized-bed drying method using balls of mixed rice and soybean protein powders. The aim of the study was to determine whether the new technique increased the falling drying rate of the wet food product. The samples were injected with a small amount of ethanol, a low-boiling organic solvent, and the material was dried in a fluidized bed of inert particles under reduced pressure. The drying rate was higher for the samples injected with ethanol than for the noninjected samples. The dried ethanolinjected samples had large pores on their surfaces, while such pores were not observed for noninjected samples. We also investigated isopropanol and ethyl acetate as potential low boiling point organic solvents for sample preparation. Similar to ethanol, ethyl acetate increased the drying rate of the wet samples compared to that of their noninjecteci samples. In contrast, isopropanol injection had no significant effect on the drying rate. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Angular Momentum   Dirac Equation   Elasticity   Quantum Mechanics   Solid   Spin  

摘要： Quantum mechanical spin angular momentum density, unlike its orbital counterpart, is independent of the choice of origin. A similar classical local angular momentum density may be defined as the field whose curl is equal to twice the momentum density. Integration by parts shows that this spin density yields the same total angular momentum and kinetic energy as obtained using classical orbital angular momentum. We apply the definition of spin density to a description of elastic waves. Using a simple wave interpretation of Dirac bispinors, we show that Dirac's equation of evolution for spin density is a special case of our more general equation. Operators for elastic wave energy, momentum, and angular momentum are equivalent to those of relativistic quantum mechanics. [ABSTRACT FROM AUTHOR]