Empirical correlations for predicting the self-leveling behavior of debris bed

Studies on the self-leveling behavior of debris bed are crucial for the assessment of core-disruptive accident (CDA) occurred in sodium-cooled fast reactors (SFR). To clarify this behavior over a comparatively wider range of gas velocities, a series of experiments were performed by injecting nitrogen gas uniformly from a pool bottom. Current experiments were conducted in a cylindrical tank, in which water, nitrogen gas and different kinds of solid particles, simulate the coolant, vapor (generated by coolant boiling) and fuel debris, respectively. Based on the quantitative data obtained (mainly the time variation of bed inclination angle), with the help of dimensional analysis technique, a set of empirical correlations to predict the self-leveling development depending on particle size, particle density and gas injection velocity was proposed and discussed. It was seen that good agreement could be obtained between the calculated and experimental values. Rationality of the correlations was further confirmed through detailed analyses of the effects of experimental parameters such as particle size, particle density, gas flow rate and boiling mode. In order to facilitate future analyses and simulations of CDAs in SFRs, the obtained results in this work will be utilized for the validations of an advanced fast reactor safety analysis code.     

Liberation of actin from actomyosin in meats heated to 65°C

This study investigated whether actin liberation from myofibrils occurs during the heating of various muscles, as well as squid mantle muscle at temperatures, such as 60°C, employed for vacuum cooking of meats. Actin liberation was demonstrated in scallop striated adductor muscle, but not in beef, pork, or chicken, using the detection method previously employed with squid muscle, in which liberated actin was detected with SDS-PAGE, in the supernatant obtained by centrifugation of the homogenate of heated muscle in 0.2M KCl at a neutral pH. However, actin liberation was demonstrated in beef, pork and chicken by a new detection method, in which heated muscle was homogenized in 0.6M KCl or NaCl at a slightly alkaline pH and maintained at 4°C for 16h with stirring, after which the homogenate was diluted three times with water and centrifuged to obtain the supernatant containing the liberated actin. This new method indicated that actin liberation in beef, pork, and chicken was marked by heating at 65°C, but scarcely induced at 80°C. Thus, the liberation of actin from myofibrils may contribute to the greater tenderness of vacuum-cooked meat (meat heated at a low temperature for long time), as compared with meat prepared by cooking at a higher temperature.     

Pulsed oscillation of GaAlAs/GaAs surface-emitting injection laser

We report the fabrication and lasing properties of the first GaAlAs/GaAs surface-emitting injection laser. The threshold current was 330 mA for 20 ?m? electrode at 77 K under pulsed conditions (? = 7960 ?). In some devices we achieved room temperature pulsed oscillation.     

Evaluation study on properties of a macroporous silica-based CMPO extraction resin to be used forminor actinides separation from high level liquid waste

Basic properties of a silica-based octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO) extraction resin (CMPO/SiO2-P) was investigated.Adsorption behavior for some rare earth elements (RE) which are constituents of high level liquid waste (HLLW) and the long-term stability of the extraction resin in nitric acid solution were examined.The CMPO extraction resin was significantly stable in 3 mol·L?1 HNO3 solution at 50oC.Furthermore,the RE(III) were efficiently separated from non-adsorptive fission product (FP) elements such as Sr(II) in a column experiment using a highly nitric acid solution.The separation behaviors of the elements are considered to result from the difference in their adsorption and elution selectivity based on the complex formation with CMPO.There was no strong dependency of RE(III) separation efficiency on feed solution flow rate.Only from the perspectives of the acid-resistant behavior of CMPO extraction resin and the elution kinetics for the metal ions with the extraction resin,the CMPO extraction resin can be used in the modified MAREC process for HLLW partitioning.     

Creep-fatigue interaction properties of nickel-based superalloy 617

High-temperature fatigue properties were investigated for a nickel-based superalloy 617 as a typical candidate material for high-temperature components using an advanced ultra super critical (A-USC) power plant. Creep-fatigue data obtained by strain-controlled tests at 700 ? C was analyzed for the superalloy 617 focused on position of hold at peak strain in comparison with continuously cycled tests. The fatigue life was the shortest with the hold tensile strain wave, which showed mainly intergranular fractu...     

Anti-beta-crystallin antibodies (mouse) or sera from humans with age-related cataract are cytotoxic for lens epithelial cells in culture

Although the motivation to quit using substances is an important prognostic and treatment-matching factor in substance abuse treatment, there is limited information on motivation to quit among individuals with schizophrenia. This study used the five-stages-of-change model to evaluate the motivational levels of 497 individuals with schizophrenia or schizoaffective disorder in an outpatient mental health clinic. Rates of substance abuse, motivation levels to quit each specific substance, and correlates to motivational levels were evaluated. At least one substance use disorder was diagnosed in 224 of the subjects (45%); however, there was significant variability among the caseloads of the outpatient division teams. The patients in the triage/acute services and community outreach teams had substance abuse rates of about 70 percent. Most subjects had low motivation to quit substances, and the rates varied according to substance (range of 41% for opiates to 60% for cocaine). Treatment-matching strategies are suggested in the motivation-based treatment model.     

Granularity and Surface Structure of Ground Granulated Blast-Furnace Slags

Ground granulated blast-furnace slags (GGBS) show improved hydration reactivity when granularity fineness increases, but the reason for the improvement in reactivity is still unknown. GGBS specimens with Blaine surface areas of 4680, 6470, and 8050 are analyzed, but the conventional reactivity criteria, such as degree of vitrification, basicity, and mineralogical composition, of the GGBS show no significant differences. X-ray photoelectron spectroscopic analysis, however, successfully distinguishes and identifies SiO₂ gels as well as glassy phases of CaO-SiO₂ and Al₂O₃-SiO₂ in the slag surfaces, where, with an increase in the Blaine surface area of the slag, CaO-SiO₂-type glass becomes dominant and contributes to the evolution of hydration, determined in terms of silicate anion morphology by the trimethylsilylation (TMS) method.     

A new formulation of laser step-diagonal measurement—two-dimensional case

The laser step-diagonal measurement modifies the diagonal displacement measurement by executing a diagonal as a sequence of single-axis motions. It has been claimed that the step-diagonal test enables the identification of all the volumetric error components, including linear errors, straightness and squareness errors, in three-dimensional space. In this paper, we show that the conventional formulation of the step-diagonal measurement is valid only when implicit assumptions related to the configuration of laser and mirror setups are met, and that its inherent problem is that it is generally not possible to guarantee these conditions when volumetric errors of the machine is unknown. To address these issues, we propose a new formulation of the step-diagonal measurement, in order to accurately identify volumetric errors even under the existence of setup errors. To simplify the discussion, this paper only considers the two-dimensional version of laser step-diagonal measurement to estimate volumetric errors on the XY plane. The effectiveness of the proposed modified identification scheme is experimentally investigated by an application example of two-dimensional laser step diagonal measurement to a high-precision machine tool.     

Automated Two-machine Flowshop Scheduling: A Solvable Case

This paper considers new flowshop scheduling problems related to automated manufacturing systems in which n jobs are processed on two machines M_a and M_b in this order. The job transportation between two machines is done by a single automated guided vehicle (AGV), and is crucial because no machine has buffer storage for work-in-process (WIP) and hence a machine cannot release a finished job until the empty AGV becomes available at that machine, while the AGV cannot transfer an unfinished job to a machine until the machine is empty. O(n³) algorithms are given in this paper to find optimal sequences of n jobs that minimize their maximum completion time (i.e., makespan). Some numerical results are also given to evaluate the effect of computing optimal sequences.