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21.
野外试验场黄土的理化分析   总被引:7,自引:6,他引:7  
本实验为低,中水平放射性废物浅地层处置安全评价提供现场土壤的物理化学参数。采样深度在0.5-9.1m范围内,每个样品进行10项测定;矿物组成,粒度分布、密度、总孔隙度、有效孔隙度、给水度、持水度、渗透系数、阳离子交换容量、含水量。  相似文献   
22.
Dynamic recrystallisation at interfaces has been suggested as the bonding mechanism in the joining of metallic tapes, during very high power ultrasonic additive manufacturing. To understand the reasons for such occurrence of dynamic recrystallization, thermal transients from the interface regions were recorded during processing of aluminum alloy (3003 and 6061 series) and 11 000 copper tapes under similar conditions. Measurements in 3003 Al were also carried out for different processing parameters. Measured peak temperatures were seen to increase with increase in shear strength of the material and ultrasonic vibration amplitude. The observations have been rationalized based on interfacial heating at asperities due to adiabatic plastic deformation.  相似文献   
23.
Porcine articular cartilage tissue was crushed using Multi-Beads-Shocker and digested with trypsin and collagenase type II. Chondrocyte cell yield was maximized by automatic crushing for 10 s, which was 4 times that by manual dicing with a surgical blade and might be useful for the automation of the cell processing.  相似文献   
24.
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the Chow test, which is well known as a standard method for detecting structural change in time-series data.  相似文献   
25.
An interface bioreactor was used in the biodesulfurization (BDS) of dibenzothiophene (DBT) with Rhodococcus erythropolis ATCC 53968. Although this strain could efficiently degrade DBT to 2-hydroxybiphenyl (2-HBP), the microbial film peeled off from the surface of the carrier (agar plate) to an organic phase (dodecane or tetradecane). To overcome this problem, a UV mutant, which strongly adhered to the carrier surface, was obtained by a new screening method. The best UV mutant (UM-021) could efficiently catalyze the BDS and the microbial film did not peel off from the surface of the carrier to tetradecane layer.  相似文献   
26.
To establish a method for sensitive, accurate, and precise determination of Se in real samples, isotope dilution analysis using high-power nitrogen microwave-induced plasma mass spectrometry (N2 MIP-IDMS) was conducted. In this study, freeze-dried human blood serum (Standard Reference Material, NIES No. 4) provided by NIES (National Institute for Environmental Studies) was used as a real sample. The measured isotopes of Se were 78Se and 80Se which are the major isotopes of Se. The appropriate amount of a Se spike solution was theoretically calculated by using an error multiplication factor (F) and was confirmed experimentally for the isotope dilution analysis. The mass discrimination effect was corrected for by using a standard Se solution for the measurement of Se isotope ratios in the spiked sample. However, the sensitivity for the detection of Se was not so good and the precision of the determination was not improved (2-3%) by N2 MIP-IDMS with use of the conventional nebulizer. Therefore, a hydride generation system was connected to N2 MIP-IDMS as a sample introduction system (HG-N2 MIP-IDMS) in order to establish a more sensitive detection and a more precise determination of Se. A detection limit (3 sigma) of 10 pg mL-1 could be achieved, and the RSD was less than 1% at the concentration level of 5.0-10.0 ng mL-1 by HG-N2 MIP-IDMS. The analytical results were found to be in a good agreement with those obtained by the standard addition method using conventional Ar ICPMS.  相似文献   
27.
This article presents the California System of Care Model for youth with severe emotional disturbances as an illustration of how ongoing assessment of the costs and outcomes of service delivery can be an integral part of a service delivery model. The core of this model, developed initially in Ventura County, California, is a five-step planning process that guides care system development and implementation. The implications of each stage of the planning process for evaluation and feedback at the child, family, and system levels are highlighted. A set of principles for selecting outcome measures deriving from the planning process are also presented that, in conjunction with the planning model, serve as guidelines for establishing outcome measures within care systems. The resulting specific plan for measuring system- and client-level outcomes deriving from this process, along with challenges to the implementation of the outcome management plan, is described.  相似文献   
28.
Catalytic oxidation of biphenyl derivatives was investigated using laccase in a homogeneous aqueous-organic system. A thermostable laccase from Trametes sp. showed the highest catalytic activity for the oxidation of 4-hydroxybiphenyl (4-HB) at a reaction temperature of 60 degrees C when dimethylsulfoxide (DMSO) was employed as a co-solvent. Furthermore, the catalytic performance was successfully enhanced by the incorporation of a laccase mediator system (LMS) into the aqueous-DMSO media. The catalytic performance strongly depended on the type of mediator, and the highest activity was observed with 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as mediator, suggesting the importance of the selection of a suitable mediator. It was verified that this mediator system is applicable to the oxidation of several biphenyl derivatives with hydroxyl groups.  相似文献   
29.
Abstract

Using a heated double-channel mould, cored rods with pure tin as a clad material and Sn-Bi, Sn-Pb, and Sn-Zn eutectic alloys as core materials have been continuously cast. With precise control of casting variables, cored rods were successfully produced with a unidirectional structure for both core and clad materials. The effects of casting speed and mould exit temperature on cast structure were examined in an attempt to obtain an understanding of this new casting process. It was found that the dissolution of clad material occurs during casting, and the dissolution process is rapid and sensitive to the process variables. Excess dissolution of clad material leads to metal breakout. In order to reduce the dissolution, lower mould exit temperatures with faster casting speeds should be employed.  相似文献   
30.
Wall-flow channel models and soot deposition models based on micro scale considerations are integrated into global 3D diesel particulate filter simulations. In addition, transient and steady-state simulations are combined to understand at the same time short- and long-time behaviour of the diesel particulate filter (DPF). The functionality of the simulation tool is achieved and correlations with measured data encourage the use of the model as a tool to predict DPF behaviour.  相似文献   
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