Changes in sheath properties of rainbow trout eggs during cold and frozen storage

Rainbow trout eggs (V/VI Maier scale maturity stage) stored at 2 and −25°C were studied for hardness, lipid components, peroxides and conjugated diene and triene groups. The egg resistance to crushing after seven days of cold storage decreased from 87.3 to 66.0 g. The concentrates of free fatty acids, peroxides, diene and triene groups showed no tendency to increase. Changes in sheath resistance to crushing during frozen storage were significant, the resistance dropping from 87.3 to 30.0 g after 12 months of storage at −25°C. The temperature of −25°C inhibited lipolytic enzymes. Egg lipids were not oxidized before the third month of storage. After four months of storage at −25°C (hardness 46.5 g), the eggs were salted to determine the extent of hardness changes under the influence of sodium chloride solution and thermal treatment. Egg sheath hardness assays showed salting to result in hardness increasing from 46.5 to 85.0 g. Pasteurization reduced egg hardness, but the extent of reduction was not proportional to the duration of thermal treatment. Hardness reduction (down to 50.0 g) in the rainbow trout eggs during frozen storage has no detrimental effects on the suitability of eggs for delicatessen product manufacture.     

Distribution of chemical constituents in the plant parts of six tropical-origin forage grasses at early anthesis

The distribution of chemical constituents in the plant parts of six tropical forage grasses at early anthesis was studied. The forage grasses were guinea grass Panicum maximum (Jacq.); angleton grass Dichanthium aristatum (Poir.); gamba grass Andropogon gayanus (Kunth); buffel grass Cenchrus ciliaris (L.); birdwood grass Cenchrus setigerus (Vahl.); and rhodes grass Chloris gayana (Kunth.). Apart from ether extract, which generally decreased from the inflorescence down to the basal culm, and crude fibre, which increased from the inflorescence down to the basal culm, no clear gradient of constituents within the plants could be established for any of the forage grass species.     

氮离子注入剂量与金属表面硬度的关系研究

对七种金属材料研究了氮离子注入剂量φ与材料表面显微硬度ＨＶ的关系，与材料的磨损摩擦性能不同，ＨＶ产不随φ的增加而调增加而调增也不存在饱和剂量，     

Qualitative Estimation of Mineral Grain Sizes by Ultrasonic Laser Spectroscopy

For elastic waves in geomaterials, the method is proposed to determine experimentally the frequency dependence of attenuation factor by ultrasonic laser excitation and estimate the characteristic sizes of mineral grains. An example is shown for using the method in question for structural analysis of ferrous quartzite samples.     

A study on yttrium doping in lead tungstate crystals

In this paper we present results of a study on the yttrium doping in lead tungstate crystals. The crystal growth by modified Bridgman method is described. Results of trace analysis on raw materials and crystals are presented. The segregation coefficient of yttrium ions in lead tungstate crystals was determined. The scintillation emission and longitudinal transmittance spectra, light output, decay kinetics, light response uniformity and radiation damage were measured. It is found that yttrium doping suppresses slow scintillation component and improves radiation hardness of lead tungstate crystals.     

硼镁矿常压法制取硼砂的工艺研究

介绍了西藏硼镁矿采用常压制取硼砂的方法 ,着重讨论了影响反应的几个因素 ,实验结果显示反应时间 2 5h ,反应温度沸腾状态 (约 10 6℃ ) ,液固比 3～ 3 5 ,碱量为理论量的 110 % ,碳酸氢钠采用分批投料 ,常压操作 ,碱解率 98 8% ,回收率 95 %以上。考察了工业规模装置下的运行状况 ,结果表明 ,矿石碱解率 96 %以上 ,产品回收率达 85 %以上     

把资源优势转化为经济优势——发展云南省铜工业的思考

本文着重介绍了云南省铜资源的结构及其基本特点、资源开发利用现状、存在问题,提出了把资源优势转化为经济优势的措施与建议。     

黄金选矿年评(待续)

综述了国内外黄金储量、生产和需求情况，并对黄金选矿生产工艺的最新进展进行了评述。     

The quality and sensory attributes of cookies supplemented with fluted pumpkin (Telfairia occidentalis Hook) seed flour

Replacing wheatflour (WHF) with defatted fluted pumpkin (Telfairia occidentalis Hook) seed flour (FPF) at levels of 0–25% was investigated for its effect on chemical, physical, sensory and nutritional properties of cookies (biscuits). Protein quality was evaluated by using weanling albino rats fed a diet of cookies, which were formulated to supply 10% protein, with a casein diet as a control. Up to 15% substitution of WHF with FPF produced acceptable cookies with spread ratio, hardness, colour and flavour similar to the control (100% WHF) cookies. Use of higher levels (20–25%), however, resulted in reduction in these quality attributes. When WHF was replaced with 15% FPF, there was an increase of 84.6% in crude protein, 62.9% in calcium, 131.0% in potassium and 61.6% in phosphorus contents of composite cookies. There were no significant (P > 0.05) differences between the values obtained for protein efficiency ratio, net protein ratio and true digestibility of cookie diets containing 15–20% FPF, and casein when fed to rats.