Methylcyclohexane production under fluctuating hydrogen flow rate conditions

Energy storage using liquid organic hydrogen carrier (LOHC) is a long-term method to store renewable energy with high hydrogen energy density. This study investigated a simple and low-cost system to produce methylcyclohexane (MCH) from toluene and hydrogen using fluctuating electric power, and developed its control method. In the current system, hydrogen generated by an alkaline water electrolyzer was directly supplied to hydrogenation reactors, where hydrogen purification equipment such as PSA and TSA is not installed to decrease costs. Hydrogen buffer tanks and compressors are not equipped. In order to enable MCH production using fluctuating electricity, a feed-forward toluene supply control method was developed and introduced to the system. The electrolyzer was operated under triangular waves and power generation patterns of photovoltaic cells and produced hydrogen with fluctuating flow rates up to 7.5 Nm³/h. Consequently, relatively high purity of MCH (more than 90% of MCH mole fraction) was successfully produced. Therefore, the simplified system has enough potential to produce MCH using fluctuating renewable electricity.     

Rapid discharge performance of composite electrode of hydrated sodium manganese oxide and acetylene black

Hydrated sodium manganese oxide was synthesized by reducing permanganate ion using ethanol by a sol–gel method. By including acetylene black in the synthetic reaction, we obtained composite materials in which sodium manganese oxide hydrate particles were small and mixed well with the acetylene black. We evaluated those composites as a lithium battery cathode and found that they showed 170 mA h g⁻¹ under 5 mA g⁻¹ and 117 mA h g⁻¹ under 5 A g⁻¹ on the basis of composite weight. This rapid discharge performance was probably caused by the favorable contact condition of the composite constituents.     

Preparation and Electric Properties of Dense Nanocrystalline Zinc Oxide Ceramics

This communication reports on the preparation and electric properties of dense nanocrystalline ZnO ceramics. By spark plasma sintering, nanocrystalline (∼100 nm) ZnO ceramics with a high density of 98.5% were obtained at a very low temperature of 550°C. Electric property measurement revealed a novel conduction nonlinearity in the sample sintered at 500°C. This phenomenon is due to the nanometerization of ZnO crystal and the grain boundary layer with an amorphous interfacial layer.     

Perceived group devaluation, depression, and HIV-risk behavior among Asian gay men.

[Correction Notice: An erratum for this article was reported in Vol 27(3) of Health Psychology (see record 2008-08834-013). In the aforementioned article, the second sentence of the Results portion of the abstract should read: Among participants most attracted to Whites, group devaluation was associated with higher levels of nonprimary partner UAI; but was associated with lower levels of nonprimary partner UAI among those most attracted to non-Whites.] Objective: This study examined depressive mood and HIV-risk behavior in relation to perceived group devaluation and group identity. Design: Cross-sectional survey of 192 Asian gay men. Main Outcome Measures: Depressive mood assessed using the Centers for Epidemiological Studies Depression Scale (CES-D) and self-reported receptive or insertive unprotected anal intercourse (UAI) in the past 3 months. Results: Group devaluation was positively associated with depressive mood. Among participants most attracted to Whites, group devaluation was associated with higher levels of nonprimary partner UAI, among those most attracted to non-Whites. Among participants reporting higher levels of group devaluation, those with more positive personal evaluations of the Asian gay community had lower levels of total UAI compared to those with more negative personal evaluations of the Asian gay community. Conclusions: Results suggest that group devaluation is associated with higher levels of depressive mood among Asian gay men. Asian gay men most attracted to non-Whites or hold more positive evaluations of their group may be buffered from the influence of high perceived group devaluation on UAI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Perceived group devaluation, depression, and HIV-risk behavior among Asian gay men": Correction to Chae and Yoshikawa (2008).

Reports an error in "Perceived group devaluation, depression, and HIV-risk behavior among Asian gay men" by David H. Chae and Hirokazu Yoshikawa (Health Psychology, 2008[Mar], Vol 27[2], 140-148). In the aforementioned article, the second sentence of the Results portion of the abstract should read: Among participants most attracted to Whites, group devaluation was associated with higher levels of nonprimary partner UAI; but was associated with lower levels of nonprimary partner UAI among those most attracted to non-Whites. (The following abstract of the original article appeared in record 2008-03424-002.) Objective: This study examined depressive mood and HIV-risk behavior in relation to perceived group devaluation and group identity. Design: Cross-sectional survey of 192 Asian gay men. Main Outcome Measures: Depressive mood assessed using the Centers for Epidemiological Studies Depression Scale (CES-D) and self-reported receptive or insertive unprotected anal intercourse (UAI) in the past 3 months. Results: Group devaluation was positively associated with depressive mood. Among participants most attracted to Whites, group devaluation was associated with higher levels of nonprimary partner UAI, among those most attracted to non-Whites. Among participants reporting higher levels of group devaluation, those with more positive personal evaluations of the Asian gay community had lower levels of total UAI compared to those with more negative personal evaluations of the Asian gay community. Conclusions: Results suggest that group devaluation is associated with higher levels of depressive mood among Asian gay men. Asian gay men most attracted to non-Whites or hold more positive evaluations of their group may be buffered from the influence of high perceived group devaluation on UAI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Minor actinide transmutation in fast reactor metal fuels irradiated for 120 and 360 equivalent full-power days

An irradiation experiment on uranium–plutonium–zirconium (U–Pu–Zr) alloys containing 5 wt% or less minor actinides (MAs) and rare earths was carried out in the Phénix fast reactor. The isotope compositions of the fuel alloys irradiated for 120 and 360 equivalent full-power days (EFPDs) were chemically analyzed by inductively coupled plasma–mass spectrometry after 3.3–5.3 years of cooling. The results of chemical analysis indicated that the discharged burnups of the fuel alloys irradiated for 120 and 360 EFPDs were 2.1–2.5 and 5.3–6.4 at%, respectively. The changes in the isotopic abundances of plutonium, americium, and curium during the irradiation experiment were assessed to discuss the transmutation performance of MA nuclides added to U–Pu–Zr alloy fuel. Multigroup three-dimensional diffusion and burnup calculations accurately predicted the changes in these isotopic abundances after fuel fabrication. An evaluation of the MA transmutation ratio based on the results of chemical analysis revealed that the quantity of MA elements in the U–19Pu–10Zr–5MA (wt%) alloy decreased by about 20% during the irradiation experiment for 360 EFPDs.     

Online preconcentration by transient isotachophoresis in linear polymer on a poly(methyl methacrylate) microchip for separation of human serum albumin immunoassay mixtures

Online preconcentration of human serum albumin (HSA) and its immunocomplex with a monoclonal antibody by on-chip transient isotachophoresis is reported. An 800-fold signal enhancement was achieved following the preconcentration on standard cross-channel microchips made of poly (methyl methacrylate). Sample injection, preconcentration, and separation were done continuously and controlled solely by a sequential voltage switching program. The preconcentration was followed by on-chip nondenaturing gel electrophoresis in methylcellulose solution. The method was applied to microchip electrophoresis immunoassay of HSA. Baseline separation of HSA and its immunocomplex was achieved in 25 s in the first 1 cm of the microchannel. In a direct immunoassay, the minimum detectable concentration of fluorescent labeled HSA by laser-induced fluorescence detection was 7.5 pM.     

Assignment problem for system with precedence relationships among elements

We have studied the problem of assign elements to an ordered sequence of stations such that the precedence relations are satisfied. At this time, we can obtain the best evaluation value decided under certain constrained conditions to the assignment. This kind of problem includes the line balancing problem. In addition, this can be adjusted to various problems by changing the constrained condition and objective function. These problems can be shown as sequential partitions of the nodes of a directed acyclic graph into subsets. We especially consider the problem of finding a minimum total cost of the cut edge under the restriction of the size of block. In this paper, we propose the general framework for sequential partitions of directed acyclic graphs. We also describe an efficient algorithm that can be used to reduce computational requirements and, possibly, storage. We estimate that the complexity of the algorithm is the polynomial order, if structure of directed acyclic graphs is near parallel. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 121(2): 54–62, 1997