Piezoelectric Properties of Pb(Mg1/3Nb2/3)O3 PbTiO3 -PbZrO3 Ceramics Modified with Certain Additives

Effects of additives on the piezoelectric properties of Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃-PbZrO₃ ceramics in a perovskite-type structure are described. The tetragonality of Pb(Mg_1/3Nb_2/3)_0.375-Ti_0.375Zr_0.25O₃ ceramics increased with the addition of NiO, Cr₂O₃, or Fe₂O₃ but decreased with the addition of MnO₂ or CoO. The dielectric and piezoelectric properties of the base composition were improved markedly through selection of additives in proper amounts. Addition of NiO yielded a high dielectric constant and planar coupling coefficient for compositions at the morphotropic transition boundary. High mechanical Q -factors and low electrical dissipation factors were obtained by addition of MnO₂. Addition of both NiO and MnO₂ produced a mechanical Q -factor of 2051 and a planar coupling coefficient of 0.553. The resonant frequency of Pb(Mg_1/2Nb_2/3)_0.4375Ti_0.4375 zr_0.125O₃ containing MnO₂ had very low temperature and time dependence. The microstructure indicated that ceramics with a high mechanical Q -factor had a fine, uniform grain structure. Addition of Cr₂O₃ retarded grain growth and addition of MnO₂, NiO, CoO, or Fe₂O₃ promoted grain growth in the ternary system.     

Economic Evaluation of Power System Flexibility by Commercial Air Conditioner Control with Large Penetration of Photovoltaic Generation

High penetration of intermittent renewable energy such as photovoltaic (PV) and wind power could cause shortage of power system flexibility. Demand response is expected to help supply ancillary service instead of the conventional power plant. Commercial air conditioners are a promising responsive load for demand response because they account for a large proportion of power consumption in the power system. We calculate a system operation cost and hourly operation pattern of each power plant by using the optimal power generation model considering flexibility supply from controlling commercial air conditioner. We obtained the following results as an effect of commercial air conditioner control. (1) The power generation of oil fired power plants decreases at peak time and annual fuel cost of oil fired plant is reduced by approximately 30% at most in Kanto area. (2) The percentage of rated operation mode of LNG combined cycle plants increases. (3) Curtailed energy rate of PV decreases because a power storage amount by pumped hydropower generation increases. (4) Required battery capacity to reduce PV curtailed amount decreased by combining battery energy storage system in case of high penetration of PV.     

Optimum checking request policies

We discuss checking policies, in which an inspector is requested to perform the check, for a ono-unit system. Applying the unique modifications of Markov renewal processes, we analyse the stochastic behaviour of each CR policy (checking request policy) and CRSL policy (checking request and surveillance limit policy), where it is assumed that the failure time for each unit and the inspector's arrival time havo arbitrary distributions. Introducing replacement eosts, the request for the inspector to perform the check, system failure and surveillance, we derive the optimal policies which maximize the cost effectiveness under suitablo conditions for each model. In particular, wo discuss the optimal policies as a non-linear programming problem with two variables.     

Consideration of Stretchable Dry Electrodes for Smart Shirts Aimed for Biological Signal Monitoring

Dry electrodes of a smart shirt for measuring biological signals were prepared by the additive printing method using a stretchable conductive paste with Ag fillers loading. Interfacial impedance between the electrode and skin depended on the contact pressure of electrode and the moisture of stratum corneum. When moisture of stratum corneum was more than 30%, ECG could be measured using the stretchable electrodes printed on a compression shirt. However, noise signal in the ECG signal increased when the moisture of stratum corneum was less than 30%. To solve this problem, we propose to use additional electrodes made of an electrically conductive kneaded rubber.     

Gelation Mechanism of Soybean 11S Globulin: Formation of Soluble Aggregates as Transient Intermediates

Thermal association-dissociation behavior of soybean 11S globulin was investigated by sucrose density gradient centrifugation and polyacrylamide gel electrophoresis. Soluble aggregates with a molecular weight of 8 × 10⁶ were formed when 0.5% and 5% protein solutions were heated for 1 min at 100°C. At the lower protein concentration, subsequent heating caused disappearance of the soluble aggregate followed by complete dissociation into acidic and basic subunits. At the higher concentration, however, subsequent heating caused formation of highly polymerized aggregates, and gel was formed after 5 min of heating. The soluble aggregates appear to be transient intermediates in the course of gel formation of 11S globulin.     

Formation, Microstructure, and Properties of Barium Zirconium Sulfide Ceramics

The preparation, microstructure, and properties of BaZrS₃ ceramics are described. The compound was prepared by heating either an equimolar mixture of BaS and ZrS₂ or BaZrO₃ alone in CS₂ gas. The reaction of the BaZrO₃−CS₂ system was extremely rapid, as would be expected in an autocatalytic reaction caused by very strong reduction by CS₂. Well-sintered bodies were obtained only by the BaZrO₃−CS₂ reaction. The time dependence of grain growth was affected considerably when reaction and sintering occurred above 1250° C. Non-uniform grain growth which occurs when an excess of Ba is present can be interpreted in terms of secondary recrystallization resulting from segregation of BaS at the grain boundary during sintering. The BaZrS₃ ceramic was stable in air up to 550°C and was oxidized above that temperature.     

Effects of Ca++, Mg++ and Na+ on Heat Aggregation of Whey Protein Concentrates

Effect of Ca⁺⁺ on the heat aggregation of whey protein concentrates (WPC) was compared with that of Na⁺ and Mg⁺⁺. On the alkaline side of the isoelectric zone, aggregation of WPC was increased by the addition of CaCl₂, MgCl₂ or NaCl, among which CaCl₂ showed the greatest effect. The denaturation temperature of WPC determined by differential scanning calorimetry significantly decreased in the presence of CaCl₂ or MgCl₂, but increased slightly in the presence of NaCl. In the electrophoretic patterns of heated WPC, the most sensitive protein to Ca⁺⁺ was β-lactoglobulin.     

第32届世界标准日祝词 环境与标准:紧密相连

尽管里约地球峰会和日本京都国际大会的结果显示出很多政府在全球环境问题上面临困难 ,但是这些高规格会议带来的益处至少是在商业、工业和消费者中建立了一种新的理念 ,即他们可以在或不在严格法规框架下 ,自己能够采取很多措施来解决环境问题。国际标准数十年来一直是解决全球环境问题的基础工具。在全球工业和技术的加速发展中 ,国际标准主要致力于迅速增长的各类产品、加工和服务领域中的质量、安全、生产和其他有关问题。国际标准是建立在国际协商一致基础之上的。通过提供全球适用的解决方案 ,它们使所有国家从先进国家的知识和经验中…     

Economic Analysis of Hybrid Battery Energy Storage Systems Applied to Frequency Control in Power System

The battery energy storage system (BESS) is prospective energy storage in the smart grid, and the hybrid energy storage system (HESS), using two different kinds of battery, is also being studied to achieve better performance and the lower cost than the single‐battery‐type BESS. However, the cost issue has not yet been evaluated explicitly. On the other hand, BESS has been studied and offers promise for ancillary service, although HESS has not been applied to frequency control in power systems. This paper focuses on the application of HESS to frequency control and its economic analysis. In this paper, the important battery characteristics in the application to a power system are introduced and two kinds of HESS are evaluated in terms of their cost when applied to frequency control. In addition, the cost HESS is used for peak shift as well as frequency control is analyzed.     

Limonoid Glucosides in Fruit, Juice and Processing by-products of Satsuma Mandarin (Chus unshiu Marcov.)

In a study on improving utilization of waste from processing of Satsuma mandarin (Citrus unshiu Marcov.) the limonoid glucosides of fruit, juice, and by-products were measured using HPLC and TLC. All materials had the 17-β-D-glucopyranoside derivatives of limonoids reported in other commercial citrus fruit. Citrus molasses was a good source for industrial scale extraction of limonoid glucosides. An extraction system using polystyrene divinylbenzene resins, was developed which could be expanded to industrial scale.