岩屑干燥方法对原油荧光特性的影响

岩屑荧光录井中含油岩屑的干燥方法不同,对原油荧光分析具有哪些影响?它已涉及到干燥方法的优选。该文用实验的方法,对不同类型的含油岩样和现场岩屑,分别在加入和不加入强荧光钻井液添加剂的情况下,进行了多种干燥方法的对比荧光测试。实验结果表明,干燥方法不同,岩样的干燥速率不同,岩样中原油荧光特性各异。分析认为,对于老岩样,50℃烘干最好;对于新捞取的砂样,50℃烘干和太阳晒干效果相似,而且均好于其它方法。     

Experimental validation of radial reconstructed pin-power distributions in full-scale BWR fuel assemblies with and without control blade

Total fission rate measurements have been performed on full-size BWR fuel assemblies of type SVEA-96+ in the zero power reactor PROTEUS at the Paul Scherrer Institute. This paper presents comparisons of reconstructed 2D pin fission rates from nodal diffusion calculations to the experimental results in two configurations: one “regular” (I-1A) and the other “controlled” (I-2A). Both configurations consist of an array of 3 × 3 SVEA-96+ fuel assemblies moderated with light water at 20 °C. In configuration I-2A, an L-shaped hafnium control blade (half of a real cruciform blade) is inserted adjacent to the north-west corner of the central fuel assembly. To minimise the impact of the surroundings, all measurements were done in fuel pins belonging to the central assembly. The 3 × 3 experimental configuration (test zone) was modelled using the core monitoring and design tools that are applied at the Leibstadt Nuclear Power Plant (KKL). These are the 2D transport code HELIOS, used for the cross-section generation, and the 3D, 2-group nodal diffusion code PRESTO-2. The exterior is represented, in the axial and radial directions, by 2-group partial current ratios (PCRs) calculated at the test zone boundary using a 3D Monte Carlo (MCNPX) model of the whole PROTEUS reactor. Sensitivity cases are analysed to show the impact of changes in the 2D lattice modelling on the calculated fission rate distribution and reactivity. Further, the effects of variations in the test zone boundary PCRs and their behaviour in energy are investigated.     

Diffusive resistance analysis in fuel cells: Part 2. Some methods and examples

In the first part of this work a rationalisation and a generalisation of the approach to the analysis of the diffusive resistances in laboratory-scale fuel cells and electrodes was recommended and some interpretation tools for the purpose were suggested and some simple reference cases discussed.     

液体真空制冷的理论分析及实验验证

本文建立了真空制冷的数学模型，对绝热和有热交换情况下的真空制冷过程进行了理论分析，推导了两种情况下液体温度随时间的变化函数；讨论了影响液体温度变化的各种参数，其中系统压强ps、液体初始温度Tf0、汽液交界面面积A和外界热源Q是影响液体温度变化的主要因素。在理论计算基础上，进行了实验验证，并对二者进行了分析比较。实验数据和理论计算结果非常吻合，理论计算能够很好地预测水温的变化趋势。     

Experimental and numerical research on the critical temperature of laterally unrestrained steel I beams

Lateral unrestrained steel beams when subjected to high temperatures may collapse in service by lateral torsional buckling. This instability state may be predicted in the resistance, temperature and time domain. In this work the beam strength is determined in the temperature domain from a batch of numerical and experimental tests, with a specified degree of utilisation and a typical accident temperature rise.The experimental set-up is a reaction portal frame especially designed for beam elements under elevated temperatures. The specimens were heated by means of electroceramic resistances and a fibre mat specimen cover is used to increase the thermal efficiency. The material and the beam initial state conditions were considered, the experimental procedure being based on constant mechanical action under increasing thermal load.The experimental data was compared with numerical solutions, obtained from a geometric and material nonlinear analysis. A shell finite element modelling, with incremental and iterative procedures, was used in the numerical calculations. Good agreement was obtained between experimental and numerical data. However, both numerical and experimental results lead to higher critical temperatures when compared with the simplified calculation procedure presented in Eurocode for this case.     

Upstream Discharge Distribution in Compound-Channel Flumes

Common inlet design for compound-channel flumes does not ensure a proper upstream discharge distribution. As the total head in the upstream tank is the same for both main-channel and floodplain subsections, the velocity in the upstream section is also the same in both subsections. The floodplain discharge is therefore too large and a mass transfer towards the main channel occurs along the flume. This Technical Note investigates how long a compound-channel flume must be to ensure that equilibrium between subsection discharges is achieved. The required length is found to be significant compared to the actual length of experimental flumes reported in the literature.     

Components of a Variance Model for the Analysis of Repeated Measurements in Fixed-Point Comparisons

Experimental design is a statistical tool concerned with the planning of experiments to obtain the maximum amount of information from the available resources. This tool may be applied to metrology, especially for the analysis of a large number of repeated measurements (replicates) of short-term repeatability and the medium-term and long-term reproducibilities, enabling the inclusion of these “time-dependent sources of variability” in the uncertainty budget. The realization of the International Temperature Scale of 1990 (ITS-90) scale requires that laboratories usually have more than one cell for each fixed point, for comparison on a regular basis. The calculation of the uncertainty of such comparisons is considered here, taking into account these time-dependent sources of variability. These components of the uncertainty evaluated by a Type A method are obtained by the statistical analysis of the experimental results using the components of a variance model for designs consisting of nested or hierarchical sequences of measurements, as foreseen by the mainstream GUM. An application example of a balanced nested structure in the comparison of two fixed-point cells is presented.     

Design of a composite tube to analyze the compressive behavior of CFRP

A dumbbell-shaped tube is designed in order to study the compression of composites in the direction of the fibers. Three conditions are defined that ensure the validity of the experimental procedure: the cracks appear in the middle of the specimen, the strain field is homogeneous in the gauge area, and buckling must be avoided. Several tubes are manufactured and then analyzed to verify that they satisfy these three conditions. It turns out that a [0°]₁₁ woven carbon/epoxy (G939/M18) tube reinforced with [90°] unbalanced woven glass/epoxy tabs (1055/ES18) is suitable for compression tests.The non linear elastic behavior of the material is then identified. The values of the parameters are close to those identified in a pure bending test.     

间壁式液-液热交换实验及其信息化过程研究——1.工程实验、类似率分析与信息化过程(下)

<正>由图34、图35、图36和图37的数据分析,可知:从冷流体进口端到热流体进口端之间,在热流体雷诺数增大(1905.044-23101.71)过程中,l=0.9时:热流体温度增加10.8℃(温32.3-43.1℃),l=0.7时:热流体温度增加10.1℃(温33.8-43.9℃),l=0.5时:热流体温度增加9.2℃(温35.4-44.6℃),l=0.1时:热流体温度仅增加7.2℃(温38.8-46.0℃);l=0.9时:壁面温度增加12.4℃     

A two group analytical approximation solution for an external source problem without separation of space and time

This work presents the development of analytical approximation solutions for a space–time dependent neutron transport problem in two energy groups for a one dimensional system consisting of a homogenized medium with a localized external source. The approximation solutions are developed using Green’s functions, the influence of the delayed neutrons is not considered. Qualitative results for a given system are analyzed. A detailed comparison of the developed analytical approximation solutions with solutions with one energy group diffusion and P₁ equation without separation of space and time is given.