Performance characteristics of mobile heat pump for a large passenger electric vehicle

In this study, the performance of a mobile heat pump for an electric bus, which uses the wasted heat of electric devices for a heating and air source for a cooling, was evaluated. Both cooling and heating performances of the mobile heat pump were tested under various experimental conditions, and then optimized by varying the refrigerant charge and the compressor frequency. The cooling capacity at all compressor frequencies was over 23.0 kW, which is sufficient for the cooling loads of an electric bus. The heating COP decreased but the heating capacity increased with the rise of outdoor temperature and the compressor frequency. The heating COP was 2.4 at an outdoor temperature of 10.0 °C. The observed heating and cooling performance characteristics of the mobile heat pump means it could be used for cabin heating and air conditioning of an electric vehicle with a short driving range.     

Effect of the monascus pigment threonine derivative on regulation of the cholesterol level in mice

Different amino acid derivatives were synthesized during cultivation of a Monascus species. Derivatives exhibiting an inhibitory activity against HMG-CoA reductase were screened by in vitro tests. The threonine derivative had a high inhibitory activity of 38% while four other derivatives showed a greater than 23% activity. The orange monascus pigment showed a high activity of 36%. In vivo tests using female C57BL/6 mice were performed with the threonine derivative and orange pigment. Changes in the cholesterol and lipid levels in mice due to addition of the pigments were investigated. The total cholesterol (TC) level of mouse serum was reduced by 8–9% with the threonine derivative and by 16% with orange pigment. Supplementation with the threonine derivative and orange pigment decreased the LDL cholesterol level by 18–26% and increased the HDL cholesterol level by 1–9%. The atherogenic index (AI) value was reduced by 23–27% with pigment supplementation. The anti-atherosclerosis effect of monascus pigments can be induced by control of the lipid content in the serum rather than in the liver of mice.     

A direct integration approach for the estimation of time-dependent boundary heat flux

In a one-dimensional heat conduction domain with heated and insulated walls, an integral approach is proposed to estimate time-dependent boundary heat flux without internal measurements. It is assumed that the expression of the heat flux is not known a priori. Hence, the present inverse heat conduction problem is classified as a function estimation problem. The spatial temperature distribution is approximated as a third-order polynomial of position, whose four coefficients are determined from the heat fluxes and the temperatures at both ends at each measurement. After integrating the heat conduction equation over spatial and time domain, respectively, a simple and non-iterative recursive equation to estimate the time-dependent boundary heat flux is derived. Several examples are introduced to show the effectiveness of the present approach.     

Patterning of Flexible Transparent Thin‐Film Transistors with Solution‐Processed ZnO Using the Binary Solvent Mixture

Flexible transparent thin‐film transistors (TTFTs) have emerged as next‐generation transistors because of their applicability in transparent electronic devices. In particular, the major driving force behind solution‐processed zinc oxide film research is its prospective use in printing for electronics. Since the patterning that prevents current leakage and crosstalk noise is essential to fabricate TTFTs, the need for sophisticated patterning methods is critical. In patterning solution‐processed ZnO thin films, several points require careful consideration. In general, as these thin films have a porous structure, conventional patterning based on photolithography causes loss of film performance. In addition, as controlling the drying process is very subtle and cumbersome, it is difficult to fabricate ZnO semiconductor films with robust fidelity through selective printing or patterning. Therefore, we have developed a simple selective patterning method using a substrate pre‐patterned through bond breakage of poly(methyl methacrylate) (PMMA), as well as a new developing method using a toluene–methanol mixture as a binary solvent mixture.     

Energy Efficiency Analysis of MISO-OFDM Communication Systems Considering Power and Capacity Constraints

In this paper, the energy efficiency of multi-input single-output and orthogonal frequency division multiplexing (MISO-OFDM) communication systems with power and capacity constraints is investigated. By formulating the power allocation problem of MISO-OFDM communication systems, the minimum subchannel transmission power is analyzed with power and capacity constraints. Simulation results indicate that there exists a specific minimum subchannel capacity threshold. Moreover, the energy efficiency of MISO-OFDM communication systems starts to increase only when the minimum subchannel capacity exceeds the specific threshold.     

Principle and application of ball SAW devices

A thin beam of waves usually diverges due to diffraction, which is a limitation of any device using such waves. However, a surface acoustic wave (SAW) on a sphere with an appropriate aperture does not diverge but is collimated, realizing ultra‐multiple roundtrips along an equator of the sphere. This effect is caused by the balance between diffraction and focusing on a spherical surface, and it enables realization of high‐performance ball SAW sensors. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(1): 41–51, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20817     

Promising zeolite-type hydrocarbon trap catalyst by a knowledge-based combinatorial approach

Libraries consisting of more than 100 zeolite samples were prepared and examined for developing a promising HC trap catalyst. Parallel adsorptions of toluene onto the catalyst samples were conducted over a 10 × 10 array reactor under dry and wet conditions with or without a heating process three knowledge-based conditions for developing an automotive catalyst during the cold-start period. FAU and BEA type zeolites revealed a high performance of toluene adsorption under the dry condition. However, FAU type zeolite significantly decreased the amount of toluene adsorbed in the presence of water in the feed gas stream, mainly due to the hydrophobicity of the catalyst surface. Over Beta type zeolites, the toluene adsorbed was found to be considerably preserved, even after forced desorption temperature-ramping to the warm-up condition of an automotive engine. Li, K, or Ag ion-exchanged Beta zeolites seem to be particularly promising as an HC trap catalyst.     

Water-induced effects on the adsorption on polycrystalline platinum (II. Interaction of carbon monoxide and water)

The adsorption and desorption of carbon monoxide and water as well as interaction between them on polycrystalline platinum has been studied using the technique of thermal desorption spectroscopy (TDS) under ultrahigh vacuum (UHV) conditions. A small amount of water adsorbs on the surface of the platinum at 310K and desorbs readily and steadily in the temperature range of 350-450 K. When exposure of water by more than 100 L is followed by saturation exposure of carbon monoxide, the height of carbon monoxide desorption peak appeared at 790 K becomes higher. It suggests that preadsorbed water dissociates a small part of carbon monoxide to atomic carbon and oxygen on the surface of the sample. And, interaction of water and carbon monoxide (or atomic carbon) results in the water-gas shift reaction.     

Metal binding novel flaxseed peptides (linusorbs)

Linusorbs (LOs; a.k.a. cyclolinopeptides) are naturally occurring orbitides derived from flaxseed. These compounds consist of 8–10 amino acid residues, which are linked via an N ‐ to C‐terminal peptide bond with molecular masses of approximately 1 kDa. The LO circular structure makes them candidates for metal binding studies. Flaxseed extracts are known to suppress Pb and Cd toxicity. Hence, four metal salts surveyed include Zn(CH₃COO)₂, ZnSO₄, Pb(CH₃COO)₂ and Cd(NO₃)₂ with pure LOs 1–5 . Proton NMR spectra indicated interaction of LOs with metal salts in solution and were used to determine impacts of methionine oxidation on interactions with metal ions. The methyl group of methionine S,S ‐ dioxide of related LOs did not show the same shift in the presence of Zn(CH₃COO)₂ and Pb(CH₃COO)₂ observed in their methionine S ‐ oxide analogues. Metal complexes were observed forming at 10^?2 m to 10^?4 m but not at lower concentrations (10^?5 m to 10^?8 m ). Mass spectrometry data confirmed that metal binding strength varied by metal in the order Zn(CH₃COO)₂<Pb(CH₃COO)₂<ZnSO₄<Cd(NO₃)₂.     

Aquafaba,wastewater from chickpea canning,functions as an egg replacer in sponge cake

Aquafaba, the viscous liquid resulting from cooking chickpeas in water is typically discarded. However, this solution is now widely used by the vegan community as an egg replacement that adds texture to food products, such as mayonnaise, pudding, ice cream and baked goods. Sponge cake was prepared with either egg white or aquafaba derived from ten different brands of canned chickpea and the texture and colour were compared. Aquafaba obtained from each chickpea can produced foam which differed in both properties and stability. In addition, aquafaba from some brands provided comparable foam volume and stability to that achieved with egg white. The colour and texture of sponge cake made with either egg white or aquafaba were similar and acceptable, but cakes prepared with aquafaba were less springy, and less cohesive than cake that included egg white. Based on our results, it appears that aquafaba has potential to replace egg white in eggless cake recipes.