Semiconductive Trimethylamine Gas Sensor for Detecting Fish Freshness

Characteristics were studied on In₂O₃ treated with 5 mol% MgO responses to 300 ppm trimethylamine (TMA), dimethylamine (DMA), ammonia and other gases evolved from several different fish muscles stored under different conditions. Sensitivities of the In₂O₃-MgO sensor element were higher in order of TMA, DMA and ammonia over the operating range 330–620°C. Sensor responses were directly proportional to concentrations of TMA in fish muscle in the presence of other evolved gases, irrespective of types of fish muscle or storage time.     

Fractionation and Characterization of Hen's Egg Yolk Phosvitin

TWO methods for phosvitin preparation were evaluated, based on purity of the products. Phosvitin was found to be heterogeneous in the polyacrylamide-gel electropherogram in which it migrated into two components designated α and β-phosvitin. They were partially fractionated using gel filtration. The β-phosvitin contained 9.20% phosphorus, while α had 2.97%. Phosvitin was dissociated into several bands ranging in molecular weights from 18,500—60,000 daltons, in the SDS polyacrylamide-gel electropherogram. Results indicate that phosvitin is composed of several subcomponents or polypeptides which interact or polymerize in aqueous solution to form larger molecular weight aggregates.     

THE ROLE OF PRIOR AUSTENITE GRAINS IN FATIGUE CRACK INITIATION AND PROPAGATION IN LOW CARBON MARTENSITE

Abstract— A study has been made of the role of Prior Austenite Grains (PAG) in fatigue crack initiation and propagation in low carbon martensite. The occurrence of ferrite precipitation along prior austenite grain boundaries during rapid cooling will lead to the formation of intergranular cracking. This intergranular cracking has a close relationship with the reduction of the endurance limit for fine grained low carbon martensite.     

CARBON ORDERING IN Fe-C MARTENSITE Ⅱ. Crystal Structure of Long-Period Ordered Phase

Ｆｅ－１．８３Ｃ马氏体在室温时效时，超点阵衍射斑点发生分裂，表明产生了长周期有序相。分析确定该相由普通有序相γ′—ＦｅｘＣ（Ⅰ）衍生而来，周期为１０ｃ＿Ｍ（ｃ＿Ｍ为马氏体ｃ轴的长度），称为γ′—ＦｅｘＣ（Ⅱ）（ｘ＝４—１０）．其周期不随时效时间变化，但随温度升高而增加。超点阵斑点的分裂距离所对应的长周期不是ｃ＿Ｍ的整数倍，表明周期为１０ｃ＿Ｍ，１２ｃ＿Ｍ，１４ｃ＿Ｍ的３种长周期有序结构可能同时存在，其衍射线互相干涉使超点阵斑点的分裂距离不为ｃ＿Ｍ的整数分之一。根据本研究确定的长周期有序相的晶体结构，计算出的电子衍射强度与实验观测值完全符合。本文还讨论了普通有序相γ′—ＦｅｘＣ（Ⅰ）与长周期有序相γ′—ＦｅｘＣ（Ⅱ）的相互关系。     

Selective growth of carbon nanotube on silicon substrates

The carbon nanotube （CNT） growth of iron oxide-deposited trench-patterns and the locally-ordered CNT arrays on silicon substrate were achieved by simple thermal chemical vapor deposition（STCVD） of ethanol vapor. The CNTs were uniformly synthesized with good selectivity on trench-patterned silicon substrates. This fabrication process is compatible with currently used semiconductor-processing technologies, and the carbon-nanotube fabrication process can be widely applied for the development of electronic devices using carbon-nanotube field emitters as cold cathodes and can revolutionize the area of field-emitting electronic devices. The site-selective growth of CNT from an iron oxide nanoparticle catalyst patterned were also achieved by drying-mediated self-assembly technique. The present method offers a simple and cost-effective method to grow carbon nanotubes with self-assembled patterns.     

Heat-Induced Textural and Histological Changes of Ordinary and Dark Muscles of Yellowfin Tuna

When a fresh specimen of yellowfin tuna Neothunnus albacora was analyzed, the cross-sectional area of ordinary (white) muscle fiber was 3.5 times larger than that of dark muscle. As heating temperature was raised, the shear force of dark muscle became progressively larger than that of ordinary muscle. Simultaneously, the A band in the ultrastructure of both muscles was stained more densely. While the Z line in I band of dark muscle still remained, that of ordinary muscle disappeared completely by heat treatment at 60°C for 30 min. Therefore, the differences in toughness change during heat treatment correlated well with that fiber sizes and ultrastructures of the two types of muscle.     

Protein Components Precipitated from Egg White by Removal of Salt

A precipitate that formed in egg white at low ionic strength affected the transparency of heat-induced gels prepared at pH 2-4 and low ionic strength. The precipitate solubilized with SDS solution containing 2-mercaptoethanol and urea included major proteins of the egg white, as shown by SDS-polyacrylamide gel electrophoresis. The bands of ovalbumin, conalbumin and other protein were smaller when the precipitate was washed with water, but lysozyme and ovomacroglobulin probably remained in the precipitate fraction. It seemed that ovalbumin, conalbumin, and other proteins co-precipitated with these two kinds of proteins. Lysozyme added to the supernatant of egg white after dialysis, did not appear to produce turbidity upon heating at pH 2.5, but whole egg white was converted to a turbid gel upon being heated at this pH.