Influence of a fiber-network microstructure of paper-structured catalyst on methanol reforming behavior

A novel microstructured catalyst that consists of Cu/ZnO catalyst powders and ceramic fibers was successfully prepared using pulp fibers as a tentative matrix by a papermaking technique. As-prepared material, called a paper-structured catalyst, possessed porous microstructure with layered ceramic fiber networks (average pore size ca. 20 μm, porosity ca. 50%). In the process of methanol autothermal reforming (ATR) to produce hydrogen, paper-structured catalysts demonstrated both high methanol conversion and low concentration of undesirable carbon monoxide as compared with catalyst powders and pellets. The catalytic performance of paper-structured catalysts depended on the use of pulp fibers, which were added in the paper-forming process and finally removed by thermal treatment before ATR performance tests. Confocal laser scanning microscopy and mercury intrusion analysis suggested that the tentative pulp fiber matrix played a significant role in regulating the fiber-network microstructure inside paper composites. Various metallic filters with different average pore sizes, used as supports for Cu/ZnO catalysts, were subjected to ATR performance tests for elucidating the pore effects. The tests indicated that the pore sizes of catalyst support had critical effects on the catalytic efficiency: the maximum hydrogen production was achieved by metallic filters with an average pore size of 20 μm. These results suggested that the paper-specific microstructures contributed to form a suitable catalytic reaction environment, possibly by promoting efficient diffusion of heat and reactants. The paper-structured catalyst with a regular pore microstructure is expected to be a promising catalytic material to provide both practical utility and high efficiency in the catalytic gas-reforming process.     

Hierarchical semi-numeric method for pairwise fuzzy group decision making

Gradual improvements to a single-level semi-numeric method, i.e., linguistic labels preference representation by fuzzy sets computation for pairwise fuzzy group decision making are summarized. The method is extended to solve multiple criteria hierarchical structure pairwise fuzzy group decision-making problems. The problems are hierarchically structured into focus, criteria, and alternatives. Decision makers express their evaluations of criteria and alternatives based on each criterion by using linguistic labels. The labels are converted into and processed in triangular fuzzy numbers (TFNs). Evaluations of criteria yield relative criteria weights. Evaluations of the alternatives, based on each criterion, yield a degree of preference for each alternative or a degree of satisfaction for each preference value. By using a neat ordered weighted average (OWA) or a fuzzy weighted average operator, solutions obtained based on each criterion are aggregated into final solutions. The hierarchical semi-numeric method is suitable for solving a larger and more complex pairwise fuzzy group decision-making problem. The proposed method has been verified and applied to solve some real cases and is compared to Saaty's (1996) analytic hierarchy process (AHP) method.     

中国液态锂铅包层材料研究进展

液态锂铅包层是国际上普遍关注和最有发展潜力的聚变堆包层概念设计之一,而包层材料是液态锂铅包层的核心问题之一.目前,液态锂铅包层普遍选用低活化铁素体/马氏体钢(RAFM钢)作为结构材料,液态锂铅作为中子倍增剂及氚增殖剂.另外,部分设计采用了耐高温、电绝缘流道插件作为功能材料,以降低磁流体动力学效应及提高冷却剂出口温度(高于700℃).为适应液态包层的发展需求,中国科学院等离子体物理研究所FDS团队联合国内外相关研究单位,进行了具有中国自主知识产权的中国低活化马氏体钢(CLAM钢)及液态锂铅包层功能材料研发,并开展了锂铅热对流及强迫对流回路的设计、研制及腐蚀实验研究,以研究液态金属锂铅的流动特性及其与结构和功能材料的相容性.同时建立了聚变堆材料数据库平台,为促进中国聚变堆液态包层及材料技术的研究和发展提供数据支持.     

Benchmarks for psychotherapy efficacy in adult major depression.

This study estimates pretreatment-posttreatment effect size benchmarks for the treatment of major depression in adults that may be useful in evaluating psychotherapy effectiveness in clinical practice. Treatment efficacy benchmarks for major depression were derived for 3 different types of outcome measures: the Hamilton Rating Scale for Depression (M. A. Hamilton, 1960, 1967), the Beck Depression Inventory (A. T. Beck, 1978; A. T. Beck & R. A. Steer, 1987), and an aggregation of low reactivity-low specificity measures. These benchmarks were further refined for 3 conditions: treatment completers, intent-to-treat samples, and natural history (wait-list) conditions. The study confirmed significant effects of outcome measure reactivity and specificity on the pretreatment-posttreatment effect sizes. The authors provide practical guidance in using these benchmarks to assess treatment effectiveness in clinical settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Trunk motion control during the flight phase while hopping considering angular momentum of a humanoid

In previous studies, various stabilizing control methods for humanoids during the stance phase while hopping and running were proposed. Although these methods contribute to stability while hopping and running, it is possibility that the control during the flight phase could also affect the stability. In this study, we investigated whether the control during the flight phase can affect the stability of a humanoid while running. To achieve stable hopping, we developed a control system that accounts for the angular momentum of the whole body during the flight phase. In this system, the angular momentum generated by the motion of the lower body in each time interval is calculated during the flight phase, and the trunk joints are controlled to generate the angular momentum necessary to compensate for the deviation of the waist posture, which is used as the reference point for the motion coordinate system of the robot. Once the proposed control system was developed and simulated, we found that the hopping duration in the unconstrained state was extended.     

Speech recognition in living rooms: Integrated speech enhancement and recognition system based on spatial,spectral and temporal modeling of sounds

Research on noise robust speech recognition has mainly focused on dealing with relatively stationary noise that may differ from the noise conditions in most living environments. In this paper, we introduce a recognition system that can recognize speech in the presence of multiple rapidly time-varying noise sources as found in a typical family living room. To deal with such severe noise conditions, our recognition system exploits all available information about speech and noise; that is spatial (directional), spectral and temporal information. This is realized with a model-based speech enhancement pre-processor, which consists of two complementary elements, a multi-channel speech–noise separation method that exploits spatial and spectral information, followed by a single channel enhancement algorithm that uses the long-term temporal characteristics of speech obtained from clean speech examples. Moreover, to compensate for any mismatch that may remain between the enhanced speech and the acoustic model, our system employs an adaptation technique that combines conventional maximum likelihood linear regression with the dynamic adaptive compensation of the variance of the Gaussians of the acoustic model. Our proposed system approaches human performance levels by greatly improving the audible quality of speech and substantially improving the keyword recognition accuracy.     

Heat-resisting TCO films for PV cells

We developed new heat-resisting transparent conductive oxide (TCO) films with resistivity of 1.4×10⁻⁴ Ω cm, an optical transmittance of above 80% (at 550 nm) and heat-resisting temperature at above 600 °C. The TCO films consists of fluorine-doped tin oxide films coated on indium–tin oxide films. They were prepared by a spray pyrolysis deposition method on glass substrates. The 100×100 mm² dye-sensitized solar cells (DSCs) were prepared with the TCO films. An energy conversion efficiency of the DSC was improved drastically in comparison to the case with conventional TCO films.     

High Temperature Interactions Between Residual Oil Ash and Dispersed Kaolinite Powders

The potential use of sorbents to manage ultrafine ash aerosol emissions from residual oil combustion was investigated using a downfired 82 kW laboratory-scale refractory-lined combustor. The major constituents were vanadium (V), nickel (Ni), iron (Fe), and zinc (Zn). The overall ash content of residual oil is very low, resulting in total ash vaporization at 1725 K with appreciable vaporization occurring at temperatures as low as 1400 K. Therefore, the possibility of interactions between ash vapor and sorbent substrates exists. Kaolinite powder was injected at various locations in the combustor. Ash scavenging was determined from particle size distributions (PSDs) measured by a Scanning Mobility Particle Sizer. Impactor samples and X-ray fluorescence (XRF) analyses supported these data. Injection of kaolinite sorbent was able to capture up to 60% of all the ash in the residual fuel oil. However, captures of ～ 30% were more common when sorbent injection occurred downstream of the combustion zone, rather than with the combustion air into the main flame. Without sorbent addition, baseline measurements of the fly ash PSD and chemical composition indicate that under the practical combustion conditions examined here, essentially all of the metals contained in the residual oil form ultrafine particles (～0.1 μ m diameter). Theoretical calculations showed that coagulation between the oil ash nuclei and the kaolinite sorbent could account for, at most, 17% of the metal capture which was always less than that measured. The data suggest that kaolinite powders reactively capture a portion of the vapor phase metals. Mechanisms and rates still remain to be quantified.     

Neuro-fuzzy hybrid control system of tank level in petroleum plant

Shown in this paper is a practical method of control using neural network and fuzzy control techniques, where a neural network estimates the target of fuzzy control. The neural network is used to estimate the transient state of a plant which has nonlinear processes such as refrigerating and filtering. The suitable control target pattern for fuzzy control is selected according to this estimation. This method is applied to control the tank level of a solvent dewaxing plant for: 1) changing the tank outflow rate smoothly, and 2) keeping the tank level stable. The results show that this system can control the tank level effectively in both steady state and transient state