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排序方式: 共有251条查询结果,搜索用时 31 毫秒
1.
所开发的压水堆核燃料循环分析计算机经济程序包括12个子程序,代表着压水堆整个核燃料循环各种不同的工艺过程。本程序能算出压水堆核电站核燃料循环中燃料费用对发电成本的影响,给出各工艺过程对燃料成本的敏感度分析,并尽可能给出燃料循环中燃料材料及服务的价格数据. 相似文献
2.
In nuclear installations, tritiated water is generally produced in the process of detritiation of air circulating in the glove boxes. The goal of this work concerns enrichment of this tritiated water at low concentration by electrolysis. The choice of this electrolyzer was dictated by the passivity of selected materials to the radiolysis in low-level tritiated water and the selectivity of the method avoiding further elimination of tritiated water and moisture before release in environment. According to the results, it is feasible to treat non-negligible volume of low-level tritiated water using a cathodic palladium membrane coated on an ionic solid polymer membrane. Presence of a palladium black deposit on the palladium membrane improves effectiveness. Enrichment in tritiated water depends on the isotopic separation factor, thereby the current and the permeability values. 相似文献
3.
贵州温水村剖面发育有一套完整的下寒武统牛蹄塘组富有机质黑色页岩,为厘清下寒武统牛蹄塘组页岩岩相类型,明确不同岩相形成环境特征,通过采集25块该剖面页岩样品,进行岩石薄片观察、X射线衍射(全岩)分析、总有机碳含量(TOC)测定及主微量和稀土元素分析,划分出温水村剖面下寒武统页岩的岩相类型,并明确了该层位页岩的沉积环境和有机质富集特征,建立了沉积模式。根据TOC值、沉积构造和矿物组成,同时考虑岩石脆性特征,共划分出9类页岩岩相:①富有机质块状强脆性硅质细粒岩;②富有机质纹层状强脆性硅质页岩;③高有机质块状强脆性硅质细粒岩;④高有机质纹层状强脆性硅质页岩;⑤高有机质块状中等脆性硅/黏土混合质细粒岩;⑥中有机质块状强脆性硅质细粒岩;⑦中有机质纹层状强脆性硅质页岩;⑧低有机质块状强脆性硅质细粒岩;⑨低有机质纹层状中脆性硅/黏土混合质页岩。其中,前5类页岩相形成于深水缺氧、暖湿型气候和以低温热水沉积作用为主的环境,初级生产力和古盐度较高,有机质富集受控于古氧化还原条件、古生产力、古盐度、古水深、暖湿型气候和热液活动,而其他岩相有机质富集则不受热液活动影响,沉积环境初级生产力和古盐度有所下降;建立了一个受氧化还原条件、古生产力、古盐度、热液活动及暖湿型气候影响的深水陆棚相沉积模式。 相似文献
4.
不同表达谱芯片分析方法在药效机制研究中的应用 总被引:1,自引:0,他引:1
Affymetrix表达谱芯片技术是一种研究基因在不同条件下表达变化的高通量分析技术,当前在深度动态挖掘药物作用机制方面的芯片分析方法的应用研究仍比较少。以药物表达谱芯片数据为研究对象,运用不同的算法对芯片数据进行预处理,使用t检验和基因芯片显著性分析的方法筛选差异表达的基因,利用凝集型层次聚类和CPP-SOM聚类的方法对差异表达的基因进行聚类分析,最后运用两类富集分析工具DAVID和GSEA对药效可能涉及的信号通路、生物学过程进行相关生物学功能的富集。结果表明,RMA算法处理药物芯片数据优于MAS5.0算法和GCRMA算法;CPP-SOM聚类方法挖掘的数据信息更丰富;GSEA富集分析工具更适合用于药效机制的研究。本研究为新药研发提供算法支持。 相似文献
5.
为满足环境气溶胶在线进样的要求,改善电感耦合等离子体质谱计(Inductively Coupled Plasma Mass Spectrometry,ICP蛳MS)对粒子中待测核素的探测限,研制出一套具有低流量、低压降特点的狭缝虚拟撞击器,可作为气溶胶在线富集进样系统的关键部件与ICPˉMS联用。本文介绍了该狭缝虚拟撞击器的研制情况:首先由ICP蛳MS的进样条件,根据经验公式完成了理论设计,确定进样流量为11L/min,强流与弱流的流量比为10,喷射狭缝宽度为1mm,长宽比为10;然后用计算流体动力学软件Fluent R对上述结构内部的流场和粒子运动径迹进行了数值模拟,考察了喷射狭缝与收集狭缝的间距G、收集狭缝的宽度Wc及其进口曲率半径的加工偏差对收集效率的影响,得到了较优化的取值范围:G取1.0~1.2mm,Wc取1.4~1.6mm,此时的切割粒径D50约2.5μm;加工出狭缝虚拟撞击器的原型装置,对其分别用室内空气气溶胶和荧光素钠标记的单分散油酸粒子进行富集性能测量。实测结果表明:空气动力学等效直径在2.5~5μm范围内的粒子浓度得到了明显富集,5μm的粒子的富集因子达到极大值7。 相似文献
6.
以川东南盆缘复杂构造区南川地区为研究对象,基于钻井、实验分析测试等资料,开展深层页岩气富集特征研究,重点讨论地层温度、地层压力等成藏环境变化对深层页岩气富集的影响作用。研究认为:(1)优势沉积相带是页岩气藏成烃的基础,研究区五峰组—龙马溪组一段形成于深水陆棚沉积环境,优质页岩发育,具备形成页岩气藏的良好物质条件。(2)有机碳含量控制纳米级有机质孔隙的发育程度,高压—超高压环境有利于孔隙的保持,对改善深层页岩物性发挥积极作用。(3)深层页岩气具有高温、高地应力的典型地质特征。温度较压力对页岩吸附能力的影响更为明显,深层页岩气赋存方式以游离气为主;高上覆地层压力导致页岩渗透率呈指数下降,页岩气运移能力显著减弱,逸散程度降低,有利于页岩气原位聚集。(4)温度、压力变化对气体扩散作用影响复杂,高温会增大气体的扩散系数,加剧气体的运移和逸散,而高压可以减缓或抑制气体的流动,有利于页岩气保存。(5)埋深与压力系数呈现一定的正相关性,埋深对向斜型页岩气藏压力系数的影响作用显著,表明深层向斜型页岩气保存条件趋好。埋深较大的残留向斜核部、凹中隆、有反向逆断层遮挡的斜坡区是复杂构造区页岩气勘探的有利目标。 相似文献
7.
8.
Demonstration and characterization of biomolecular enrichment on microfluidic aptamer-functionalized surfaces 总被引:1,自引:0,他引:1
Thai Huu NguyenAuthor VitaeRenjun PeiAuthor Vitae Milan StojanovicAuthor VitaeQiao LinAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):58-66
This paper demonstrates and systematically characterizes the enrichment of biomolecular compounds using aptamer-functionalized surfaces within a microfluidic device. The device consists of a microchamber packed with aptamer-functionalized microbeads and integrated with a microheater and temperature sensor to enable thermally controlled binding and release of biomolecules by the aptamer. We first present an equilibrium binding-based analytical model to understand the enrichment process. The characteristics of the aptamer-analyte binding and enrichment are then experimentally studied, using adenosine monophosphate (AMP) and a specific RNA aptamer as a model system. The temporal process of AMP binding to the aptamer is found to be primarily determined by the aptamer-AMP binding kinetics. The temporal process of aptamer-AMP dissociation at varying temperatures is also obtained and observed to occur relatively rapidly (<2 s). The specificity of the enrichment is next confirmed by performing selective enrichment of AMP from a sample containing biomolecular impurities. Finally, we investigate the enrichment of AMP by either discrete or continuous introduction of a dilute sample into the microchamber, demonstrating enrichment factors ranging from 566 to 686×, which agree with predictions of the analytical model. 相似文献
9.
K. Sathish-Kumar O. Solorza-Feria J. Tapia-Ramírez N. Rinderkenecht-Seijas H.M. Poggi-Varaldo 《International Journal of Hydrogen Energy》2013
In microbial fuel cells (MFCs) efficient extracellular electron transfer microbes, also known as anode-respiring bacteria, play an important role on cell performance. This type of microbes can be developed by application of enrichment procedures. The objective of this study was to compare a chemical (only C, final terminal electron acceptor Fe(III)), an electrochemical (only E), and a hybrid method (H, i.e., E followed by 3 serial transfers in iron (III) citrate medium) enrichment methods departing from a saline–sodic soil inoculum. In the electrochemical enrichment procedure in an electrolysis cell, the inoculum was subjected to a continuous electrical stress continually by posing the cell at −150 mV/SCE (+94 mV/SHE). The only C enrichment method delivered powers superior to the only E one (higher values of PAn,max = 49 mW m−2 and PV,max = 558 mW m−3 of C compared to 33 and 379 of only E). Interestingly, overall resistance as determined by EIS was lower for only E (1240 Ω) than for only C (1632 Ω). Yet, the hybrid H method, showed electrochemical characteristics consistently superior to both only C and only E methods (higher PAn,max and PV,max, lower internal resistance). Further detailed electrochemical studies of only E-method showed that the anodic resistance decreased with the time of operation of the electrolysis cell that would be consistent with the adaptability/enrichment purpose of the method. Also, Cyclic voltammetry peaks with values close to those reported for bacterial cytochromes appeared with time of cell operation. 相似文献
10.
Using a pervaporation process, a surface-modified hydrophobic membrane was used for recovery of esters which are volatile
organic flavor compounds; ethyl acetate (EA), propyl acetate (PA), and butyl acetate (BA). A surface-modified tube-type membrane
was used to evaluate the effects of the feed concentration (0.15–0.60 wt%) and feed temperature (30–50 °C) on the separation
of EA, PA, and BA from dilute aqueous solutions. The permeation flux increased with the increasing feed ester concentration
and operating temperature. EA, PA, and BA in the permeate were concentrated up to 9.13–32.26, 11.44–34.95, and 14.96–36.37
wt%, respectively. The enrichment factors for the 0.15–0.60 wt% feed solution of EA and BA were in the range of 48.5-62.8
and 97.7-101.5, respectively. Phase separation occurred in the permeate stream because the ester concentration in the permeate
was above the saturation limit. This meant that selectivity of the membrane was high enough for the recovery of esters from
dilute aqueous solution, even though the enrichment factor of the membrane was lower than that of non-porous PDMS membrane.
The fluxes of EA, PA, and BA at 0.60 wt% (6,000 ppm) feed concentration and 40 °C were 254, 296, and 318 g/m2.hr, which are much higher than those obtained with polymer membranes. In the case of non-porous PDMS at feed concentrations
of 90-4,800 ppm and at 45 °C, it was reported that the permeate flux of EA was 1.1–5.8 g/m2.h. Compared to non-porous PDMS, the surface-modified membrane investigated in this study showed a much higher flux and enough
selectivity of esters. 相似文献