Surface and pore structure of alumina derived from xerogel/aerogel

The alkyl derivatives of boehmite were prepared by solvothermal reaction of aluminum isopropoxide in n-alcohols (ethanol, 1-butanol, 1-hexanol, 1-octanol and 1-dodecanol) and the products were recovered as aerogel/xerogel by the removal of the solvent at the end of reaction. Aerogel or xerogel can be obtained simply by using only a reaction vessel (autoclave) and the obtained products were composed of plate-like particles having a well-developed boehmite structure. The alumina powders obtained by calcination of these products had relatively large pore-volumes ranging from 1.35 to 2.56 cm³/g. Transformation into α-Al₂O₃ was retarded even after calcination at 1200 °C. The effect of n-alcohols used in the solvothermal reaction on the phase, morphology and pore-texture of the alumina samples are discussed.     

Package Design of Ready-to-Drink Coffee Beverages Based on Food <Emphasis Type="Italic">Kansei</Emphasis> Model—Effects of Straw and Cognition Terms on Consumer’s Pleasantness

To design a consumer-oriented package that complements the taste and aroma of ready-to-drink chilled-cup coffee beverages by using the food kansei model, the effects of the diameter and the color of drinking straws as well as the cognition terms of coffee on consumer sensory characteristics and preferences were investigated. Variance and factor analyses of the sensory scores for chilled-cup coffee with milk and sugar using straws of different diameters, as rated by consumer panelists, extracted two perceived factors (F1, contribution ratio 36.5%, and F2, 28.6%). A two-dimensional plot of the average F1 and F2 scores of 123 panelists showed that the perceived characteristics of the same taste and aroma varied according to the straw diameter. An image investigation of different straw colors and another sensory evaluation using “black,” “brown,” and “green” straws were also performed. A principal component analysis of the image data revealed that the sensory characteristics of coffee with milk and sugar were imaged from the straw color. The second evaluation suggested that the images of straw colors affected the sensory characteristics. In addition, cluster and multiple-comparison analyses of Internet research data from consumers regarding the cognition terms for coffee exhibited three clusters representing the cognitive characteristics of terms by consumers and by developers and the differences of attractiveness degree on the cognition terms due to the consumers’ personal attributes. These studies provide useful information for the development of packages of chilled-cup coffee beverages.     

Steam Reforming of Methanol on Copper Catalysts Supported on Large-Surface-Area ZnAl2O3

Steam reforming of methanol on various supported Cu catalysts was examined. Supports strongly affected catalyst activity and, among the catalysts tested, Cu catalyst supported on large-surface-area ZnAl₂O₄ showed the highest activity, which, to the best of our knowledge, was higher than those for the supported catalysts reported so far. For supported Cu catalysts, two species were observed. One was a dispersed Cu species having strong interaction between Cu and support, and the other was an isolated Cu species. The activity of the former species strongly depended on supports.     

Preparation of Ba2YCu3O7-δ Thin Films with Preferred Orientation through an Organometallic Route

Superconducting Ba₂YCu₃O_7-δ thin films were prepared through an organometallic route. Single-phase Ba₂YCu₃O_7-δ thin films with preferred orientation were successfully prepared on SrTiO₃ (100) single-crystal substrates at 800°C by a dip coating method using partially hydrolyzed Ba-Y-Cu organometallic solutions. Preferentially oriented Ba₂YCu₃-O_7-δ thin films were also prepared on MgO (100) substrates. By controlling the partial hydrolysis conditions, a coating solution for precursor thin films was kept accurately at the stoichiometric composition. The use of ozone gas during the pyrolysis of the precursor thin films was found to suppress the formation of BaCO₃. Ba₂YCu₃O_7-δ thin films with c -axis orientation perpendicular to a SrTiO₃ (100) substrate, which were heat-treated at 900°C for 15 min, exhibited a superconductivity transition with an onset of 90 K and an end of 75 K.     

A photocatalytic membrane reactor for gas-phase reactions using porous titanium oxide membranes

Photocatalytic membrane reactors using porous titanium oxide membranes having pore sizes of several nanometers were utilized for a gas-phase reaction of methanol. Air mixed with methanol (MeOH) vapor, the concentration of which was controlled in the range of 500–6000 ppm, was fed to the photocatalytic membrane reactor in the range of 50–500 cm³/min using several types of flow patterns. Photocatalysis with membrane permeation resulted in a large decomposition rate, compared to photocatalysis without membrane permeation. The characteristics of the reaction such as decomposition ratio of MeOH, the conversion of the decomposed MeOH to CO₂ and H₂O were found to be a function of the residence time in the reactor. The photocatalytic reaction was analyzed based on pseudo-first-order kinetics to ascertain its simplicity, and the fitted curves were found to be in a relatively good agreement with the experimental data. Apparent rate constants with and without membrane permeation were 2.5 and 1.5×10⁻⁶ m s⁻¹, respectively, indicating that the performance of the photocatalytic reaction system with membrane permeation was enhanced.     

Push-Pull Fatigue of Sintered Silicon Nitride Ceramics at Elevated Temperatures

The fatigue tests under push-pull completely reversed loading and pulsating loading were performed for silicon nitride ceramics at elevated temperatures. Then the effects of stress wave form, stress rate, and cyclic understressing on fatigue strength, and cyclic straining behavior, were examined. The cycle-number-based fatigue life is found to be shorter under trapezoidal stress wave loading than under triangular stress wave loading, and to become shorter with increasing hold time under the trapezoidal stress wave loading. Meanwhile, the equivalent time-based life curve, which is estimated from the concept of slow crack growth, almost agrees with the static fatigue life curve in the short and intermediate life regions, showing the small cyclic stress effect and the dominant stress-imposing period effect on cyclic fatigue life. The fatigue strength increased in stepwise stress amplitude increasing test, where stress amplitude is increased stepwise every given number of stress cycles, at 1100° and 1200°C. Occurrence of cyclic strengthening was proved through a gradual decrease in strain amplitude during a pulsating loading test at 1200°C in this material, corresponding to the above cyclic understressing effect on fatigue strength.     

Profiling and Imaging of Phospholipids in Brains of Abcd1‐Deficient Mice

ABCD1 is a gene responsible for X‐linked adrenoleukodystrophy (X‐ALD), and is critical for the transport of very long‐chain fatty acids (VLCFA) into peroxisomes and subsequent β‐oxidation. VLCFA‐containing lipids accumulate in X‐ALD patients, although the effect of ABCD1‐deficiency on each lipid species in the central nervous system has not been fully characterized. In this study, each phospholipid and lysophospholipid species in Abcd1‐deficient mice brains were profiled by liquid chromatography‐mass spectrometry. Among the phospholipid and lysophospholipid species that are significantly more enriched in Abcd1‐deficient mice brains, VLCFA were present in 75, 15, 5, 4, and 1 species of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, lysophosphatidylcholine, and lysophosphatidylethanolamine, respectively. Most VLCFA were incorporated at the sn‐1 position of phosphatidylcholine and phosphatidylethanolamine. Among the phospholipid species that are significantly less enriched in Abcd1‐deficient mice brains, odd‐numbered saturated or mono‐unsaturated fatty acyl moieties are contained in all phosphatidylcholine species. In addition, a number of phosphatidylglycerol, phosphatidylinositol, and phosphatidylserine species contained highly unsaturated fatty acyl moieties. Intriguingly, 44:1 phosphatidylcholine with VLCFA was mainly distributed in the gray matter, such as the cortex, but not in the white matter in the cerebrum and cerebellum. These results show that ABCD1‐deficiency causes metabolic alternation of long‐chain fatty acids and VLCFA. Moreover, our results imply a molecular mechanism for the incorporation of saturated or monounsaturated VLCFA into the sn‐1 position of phospholipids, and also indicate that the distribution of phospholipids with VLCFA may correlate with the development of X‐ALD.     

日本蓄冷(热)空调系统的发展与最新业绩

介绍了日本减缓温室效应的对策、能源与电力行业现状、蓄冷(热)技术的发展与现状及其应用实例.在区域供热制冷工程中的实际应用数据表明,蓄冷(热)技术无论从减缓温室效应还是经济性角度来说都值得推广.