Phase Diagram Calculation of Partial Metal Uranium-based Nuclear Fuel and Zirconium-based Cladding Material under Irradiation

核能是一种非常有潜力的新能源，核能的产生需要在核反应堆中进行。核燃料元件（核燃料＋包壳）材料是核反应堆中至关重要的一部分。然而核燃料元件材料在使用过程中不可避免地会受到辐照的影响，从而导致相稳定性发生改变。因此，为了保证核燃料元件能够安全高效地运行，研究辐照条件下核燃料元件的相图是十分有必要的。本论文基于CALPHAD方法，对金属型核燃料U-X二元合金、包壳材料Zr-X二元合金在辐照条件下的相图进行了计算，主要的研究成果如下： (1)基于文献报道的U-X(X:Mo，Zr)各二元系的热力学参数和扩散参数，建立了辐照条件下的有效自由能模型，研究了不同辐照条件对缺陷浓度、自扩散系数、自由能和平衡相...Nuclear energy is a very promising new energy, and it needs to be carried out in the nuclear reactors. Nuclear fuel element (nuclear fuel + cladding) materials are a key part of nuclear reactor materials.However, the nuclear fuel element materials are inevitably subject to irradiation during its application, with the appearance of irradiation effects, resulting in the change of phase stability.The...学位：工程硕士院系专业：材料学院_工程硕士(材料工程)学号：2072014115010

虎伯寮南亚热带雨林自然保护区的竹类资源及开发利用

福建省南靖县虎伯寮南亚热带雨林自然保护区的竹类资源丰富 ,有 8属 2 0种 3变种 5栽培型 ,其中梅花毛竹 ( Phyllostachys heterocycla cv.obtusangula)为福建竹类新分布 ;主要的竹林类型有毛竹林、麻竹林、绿竹林、石竹林、单竹林。竹类资源的开发利用具有广阔的前

Materials Genome Initiative and Nuclear Fuel Element Material

核能由于其高能量密度和低污染排放等优点,已经成为未来能源的重要组成部分。然而,民用核燃料材料因其特殊的放射性,实验研究的安全防护成本极高,尤其是; 经过辐照后的核燃料材料,分析和表征手段极其有限,如果采用传统的试错法材料研发方法,将会使材料的研发成本大幅提高,因此,材料基因工程的研究思路正是; 适合于新型民用核燃料材料研究的技术路线。本研究组多年来以开发新型民用核燃料元件材料为目标,通过第一性原理和CALPHAD技术的结合,先后建立了U; 、Pu等锕系元素的多组元热力学数据库,并建立了辐照场作用下的热力学模型,对辐照场作用下核燃料材料的相变热力学和动力学进行了深入研究,在热力学数据; 库的基础上,运用相场动力学模型对核燃料元件材料的凝固和时效过程组织演化规律进行了系统的研究。这种基于材料基因工程的多尺度、多组元的材料设计研发思; 路为我国新一代具有自主知识产权的民用核燃料元件材料的成分设计、组织控制、工艺优化、性能改善及服役时间预测提供了重要的理论基础,同时对材料基因工程; 方法在材料开发中的广泛应用具有重要意义。Nuclear energy is an important part of the future source of energy due; to their higher energy density and lower emission of pollutants.; However, the traditional research method of "trial-and-error" may result; in higher costs and lower efficiency because of the radioactivity of the; nuclear fuel element material. The idea of Materials Genome; Initiative(MGI) is suitable for the research and development of the; nuclear fuel element material. Focused on the nuclear fuel element; material,our research group developed a multi-component thermodynamic; database including U,Pu and other elements,by coupling CALPHAD method; and the first-principle method. Based on the thermodynamic database, the; thermodynamic model under irradiation was established and the phase; transformations under irradiation were systematically investigated. The; microstructure evolutions during solidification and aging were simulated; by using the Phase-Field method. The present multiscale and; multi-component materials design method based on MGI can provide; important information for the design of composition,microstructure; controlling and property improvement of nuclear fuels materials.中央高校基本科研业务费; 国家自然科学基金资助项

Effects of Pb~(2+) stress on nitrogen metabolism and membrane lipid peroxidation in Aegiceras conrniculatum seedlings

研究了Pb2+对桐花树幼苗氮代谢关键酶活性及膜脂过氧化的影响。结果表明:0.1~2.0 mmol.L-1Pb2+胁迫使营养液中培养的桐花树幼苗根、茎、叶的NADH-GOGAT活性降低,丙二醛含量增加,使根和茎的GS活性降低,而叶的GS在0.1~1.0 mmol.L-1Pb2+胁迫下活性增加高于对照,但受2.0 mmol.L-1较高浓度Pb2+抑制。无论是否有Pb2+胁迫,叶的GS活性都高于茎和根,而根的NADH-GOGAT活性始终高于茎和叶。根的GS和NADH-GOGAT活性受Pb2+胁迫抑制的程度明显大于茎、叶,Pb2+对根的初级氮代谢影响最大。MDA含量与GS和NADH-GOGAT活性呈负相关关系。The effect of Pb2+ stress on nitrogen metabolism and membrane lipid peroxidation in Aegiceras corniculatum seedlings was investigated.The activities of NADH-GOGAT and GS,soluble protein,and MDA content in the roots,the stems and the leaves of A.corniculatum seedlings,which were cultivated for 30 days in nutrient solution containing Pb2+,were analyzed.The results showed that the NADH-GOGAT activities in A.corniculatum seedling roots,stems,and leaves decreased under Pb2+ stress,while the contents of soluble proteins and MDA increased.The GS activities in the roots and stems decreased due to Pb2+ treatments with concentrations ranging from 0.1 to 2 mmol·L-1.GS activities in the leaves increased and was higher than that of the control.However,the activity was inhibited by Pb2+ at higher concentration of 2 mmol·L-1.Whether Pb2+ was added to the nutrient solution or not,the GS activity in the leaves was higher than those in the roots and stems.The GOGAT activity in the roots was higher than those in the leaves and stems.GS and NADH-GOGAT in roots were more sensitive to Pb2+ stress than those in stems and leaves.Thus,Pb2+ had the most effect on primary nitrogen metabolism in the root.It was also suggested that there was a negative correlation between the MDA content and the NADH-GOGAT or GS activity.福建省青年科技人才创新项目(2004J053);; 福建教育厅资助项目(JA02251);; 泉州市科技局资助项目(2003Z11

Comparative study on elderly mirror-image dextrocardia patients and the normal elderly

目的研究对比静息状态下镜像右位心老年人与正常老年人的心功能指标的差异,为相应老年人镜像右位心患者心功能退化和心衰的发生发展提供参考。方法回顾性分析厦门大学附属东南医院2006年2月至2016年7月经超声心动图及胸片诊断为镜像右位心且不合并其他异常畸形的老年患者12例(其中男7例,女5例)临床资料,与12例老年正常心志愿者对比分析左心室射血分数(EF)、左心室缩短分数(FS)、心率(HR)、每搏输出量(SV)、每分输出量(CO)等心功能指标,比较两者间是否存在明显差异。结果镜像右位心老年患者的心率、左室射血分数、左心室缩短分数、每搏输出量、每分输出量分别为(83±12.79)次/min、(0.61±0.58)、(0.32±0.40)、(57.82±11.90)mL和(4.84±1.42)L/min,正常老年人分别为(71.71±11.92)次/min、(0.61±0.57)、(0.32±0.46)、(58.71±11.78)mL和(4.22±1.22)L/min。2组人群比较,心率差异有统计学意义(P0.05)。结论镜像右位心老年患者的心率比正常老年人心率快,而其他心功能指标则无明显区别。ObjectiveBy comparing the differences of heart function between the mirror-image dextrocardia elderly and the normal elderly in the resting state,to provide a reference for the development of heart failure and heart failure in the elderly mirror-image dextrocardia patients MethodsWe collect separately12diagnosed with mirror-image dextrocardia elderly(including7males and5females)by echocardiography and chest radiographs and12normal elderly in the southeast hospital of Xiamen University from February2006to July2016,compared and analyzed cardiac function indicators as follows:Left ventricular ejection fraction(EF),left ventricular shortening score(FS),heart rate(HR),stroke volume(SV),and output per minute(CO),and to determine whether there is a difference between the two elderly.ResultsThe right heart rate,left ventricular ejection fraction,left ventricular shortening score,stroke volume,and per minute output of the mirror-image dextrocardia elderly are(83±12.79)t/min,(0.61±0.58),(0.32±0.40),(57.82±11.90)mL,and(4.84±1.42)L/min,respectively.And the normal elderly are(71.71±11.92)t/min,(0.61±0.57),(0.32±0.46),(58.71±11.78)mL,and(4.22±1.22)L/min,respectively.There are significant differences in heart function between the two groups(P<0.05),but there are no significant difference between the left ventricular ejection fraction,the left ventricular shortening score and the stroke volume per stroke(P>0.05).ConclusionThe heart rate of the elderly patients with mirror-image dextrocardia is faster than the normal elderly,and the cardiac function index of the left ventricular ejection fraction,left ventricular shortening score,stroke volume are no obvious difference.国家自然科学基金(81671667);中国博士后科学基金(2015M570436

CT检出结肠结节状病灶的影响因素

目的:利用仿真模型研究结肠结节状病灶的特征、CT扫描参数、阅片视窗及仿真成像(CTC)对CT检出病灶的影响。材料与方法:利用仿真材料制造30个结节放置到仿真人的结肠内壁上,结节分别为0.5cm隆起形、0.3cm隆起形、0.2cm隆起形、0.2cm扁平形、0.2cm高密度扁平形,每种结节6个。分别应用方案8.0mm/2.5mm/17.5(层厚/准直/螺距)和方案5.0mm/1.0mm/7.0扫描并CTC成像。对横断面扫描图像分别应用3种视窗阅片。检测不同情况下结节的显示情况。结果:窗宽1000HU,窗中心-500HU时,8.0mm/2.5mmm/17.5横断面图像及CTC显示0.5cm、0.3cm所有结节,结节边缘清楚,影像测量值与实物大小相符,而0.2cm结节,横断面图像仅隐约显示1个高密度扁平形结节,CTC图像隐约显示1个高密度扁平形和3个隆起形结节。5.0/1.0/7.0扫描横断面图像及CTC图像除0.2cm低密度扁平形结节未见显示外,其余4种结节均全部显示。窗中心-1000HU时,上述结节边缘模糊,影像测量值略偏大。窗中心0HU时,0.3和0.2cm结节未见显示,0.5cm结节显示暗淡、变小。结论:结肠结节特征、CT扫描参数、阅片视窗及仿真成像均影响CT对结节的检出,CTC对检出小结节的敏感性优于原始横断面扫描图像

The Multi-criteria Evaluation of Rockburst Proneness on Deep Buried Large Tunnel

研究目的:高铁北武夷山隧道是一座单洞双线隧道,隧道最大埋深达1 100 M,属于高应力区,开挖过程中可能会出现岩爆现象。通过对隧道高应力地区采集的岩样进行室内岩爆倾向性实验,并结合声发射监测技术,得到岩石单轴抗压强度等性能参数,先采用强度脆性系数法、变形脆性系数法、弹性应变能指标法、切向应力准则四种单指标评价方法进行岩爆倾向性评价,然后运用四指标模糊数学综合评价法进行评价。研究结论:(1)结合声发射监测技术进行岩石力学实验,获得的变形脆性系数、弹性应变能指标系数相比常规实验更加精确;(2)根据岩体性质和围岩的应力情况,在传统综合评价方法基础上增加了变形脆性系数法评判指标,结果表明采用模糊数学综合评价方法得到的评价结果与单指标评价相比,更加符合隧道岩爆的实际情况;(3)本研究成果为隧道岩爆预测提供了可行方法,对于类似工程提前防治岩爆有借鉴意义。Research purposes: North Wuyi Mountain of high-speed railway is a single hole bidirectional tunnel,and the maximum depth of the tunnel is as deep as 1100 meters,so it belongs to high stress area that may cause rockburst in the process of excavation.The indoor experiments about rockburst proneness of rock samples which were collected in high stress area of the tunnel are recorded in this paper,and some property parameters of rock like the uniaxial compressive strength were got combining acoustic emission testing.Four kinds of single index evaluation method were used to evaluate rockburst proneness firstly,including the intensity of brittleness coefficient method,the deformation brittleness coefficient method, the elastic strain energy method and the tangential stress criterion.Then the comprehensive evaluation method of fuzzy mathematical was used to evaluate.Research conclusions:( 1) Combined with acoustic emission monitoring technology,we can get two indexes more accurately than conventional experiment.( 2) According to rock properties and surrounding rock stress,we increase the evaluation indicator of deformation brittleness coefficient method.It showed that the results from the comprehensive evaluation method of fuzzy mathematical are more in line with the actual situation of the rock burst of tunnel compared with the single index evaluation.( 3) The research result provides a feasible method to predict rockburst and it is significant to prevent and control of rockburst in advance for similar engineering

EXPERIMENTAL STUDY ON FRACTAL DIMENSION CHARACTERISTICS of ACOUSTIC EMISSION of ROCK UNDER MULTILEVEL UNIAXIAL CYCLIC LOADING

通过对三种岩石试样进行单轴循环加载试验,获得岩石试样加载过程中声发射事件率、能量率和空间位置分布数据。运用相空间重构理论直接从时间序列上通过g-P算法求得事件率和能量率关联分维,根据柱覆盖法求解得到声发射事件源空间分布关联分维。研究结果表明,声发射事件率、能量率和空间分布都具有分形特性,且声发射源空间分布分形特性最为显著。相空间的选取对关联维数有一定影响,相空间取值为4时能够较好地计算关联维数。将不同加卸载循环声发射源空间分布的变化趋势和声发射源空间分布关联维数变化趋势进行对比发现,声发射关联维数能够很好地反映岩石内部损伤破坏的发展。在等压加卸载条件下,声发射源空间分布关联维数显著突增。随着加卸载循环应力的增加,关联维数总体呈下降趋势,在达到较高应力时,关联维数则在较小区间内波动或下降趋势变得极其缓慢。该特点可以作为矿山地压微震监测预警的参考依据。Experiments on acoustic emission(AE) characteristics of fractal were carried out under uniaxial multilevel cyclic loading.AE rate, energy rate and spatial distribution of different rock specimens were obtained.Relevant fractal dimensions of AE rate and energy rate were figured out through G-P algorithm based on the theory of reconstruction of phase space.Relevant fractal dimensions of AE spatial distribution was figured out through column-covering method.The results show that AE rate, energy rate and AE spatial distribution are of fractal characteristics,and among them, AE spatial distribution has the most obvious fractal characteristics.Phase space has some effects on relevant fractal dimensions, and it is better to choose 4 as the basic dimension for correlation dimension calculation.The comparison of development trend of AE spatial distribution and relevant fractal dimensions under different cycles shows that fractal characteristics can reflect the statistical evolution of the micro-cracks in rock.Relevant fractal dimension increases under isobaric cyclic loading and decreases with the increasing of stress.Relevant fractal dimensions fluctuate in a small range or decrease slowly when the higher stress has been reached.The characteristics above can be used as the reference for micro-seismic monitoring warning on ground pressure in mining.国家“十二五”科技支撑计划项目(2013BAB02B06); 国家科技部科研院所技术开发研究专项资金项目(2013EG215024

The Techniques and Application of Anhydrous Packaging with Chilled Sawdust in Longdistance Transportation of Live Kuruma Shrimp Marsupenaeus japonicus Broodstock

本文报道了以冷冻木屑为填充料,长途运输日本囊对虾(MArSuPEnAEuS JAPOnICAS)亲虾的无水包装技术及其应用实验。亲虾在室温条件下经3~5H适应性暂养后,以1℃·H-1降温速率逐步降至15℃,并维持该温度。包装前1H再把水温降至亲虾出现僵硬或侧卧为冷休克标志,大约11℃左右。包装时,在泡沫箱内铺上冷冻木屑3~5CM,再放上一层排列整齐的亲虾,如此一层木屑一层亲虾,至表层以木屑装满箱为止。一个航空运输专用箱(60x45x32CM)可装70~80尾亲虾。箱内可根据运输时间放置降温剂(干冰)1~2块。2004年~2006年,从厦门空运亲虾到河北黄骅市渤海水产资源增殖站,36批次,亲虾总数量达16584尾,运输过程死亡1436尾,存活率为91.34%。文中还就包装过程人为操作不当的影响、常见问题和各种活虾运输方法的利弊进行了分析与讨论。This article attempts to describe in detail techniques and application of anhydrous packaging with chilled sawdust in long-distance transportation of live kuruma shrimp Marsupenaeus japonicus broodstock.The broodstock were acclimatized for 3~5 hr under the condition of room temperature, and the water temperature was gradually dropped at a rate of 1℃·h-1to 15℃ which was maintained.One hour before the packing, the water temperature was again made to drop to the temperature(some 11℃)at which the c old shock sign of the shrimp, stiff or lying on side, appeared.During the process of packing, 3~5 cm layer of chilled sawdust was put at the bottom of a foam box, then a layer of neat rows of shrimp was put on the chilled sawdust, and a layer of chilled sawdust was again put on shrimp until the top surface of box was filled with chilled sawdust.A special air transport box(60×45×32cm)can hold 70 ~ 80shrimps., and 1~2 pieces of the cooling agent(dry ice)were placed in the box according to the air transportation period.From 2004 to2006, a total number of 16584 shrimp(36 batches)were transported from Xiamen to Huanghua Bohai Multiplication Station of Aquatic Resources of Hebei Province by air, with survival rate of 91.34%.The harmful effects caused by improper handling and common problems during the packing process, the pros and cons of various methods to transport live shrimp were also analyzed and discussed.福建省科技重点计划项目(2012N0030

深圳海域细菌总数及可培养细菌总数的分布及其在环境评价中的应用研究

采用荧光显微镜直接计数法及2216E平板计数法对深圳海域水体细菌数量分布状况进行研究,结果发现细菌总数普遍高于可培养细菌总数1~2个数量级,可培养细菌所占的比例为0.13%~88.65%。清洁水域YMK001站位及污染严重的深圳湾GDN053站位始终是细菌总数的高值区。可培养细菌总数与细菌总数、CODMn及BOD5相关关系不显著,不能准确反应细菌总数的变化趋势及环境水体有机物的存在状态;而细菌总数与CODMn及BOD5相关关系显著且相对稳定,与环境水体有机物间呈现正相关关系。可见细菌总数相对于可培养细菌总数更适合于大范围海域的水质监测及不同海域的比较分析