扇贝柱质构分析的测试条件

研究了扇贝柱质构分析(TPA)的测定方法.考察了TPA测定时扇贝柱适宜的预处理方法,比较了压缩程度、压缩速率对扇贝柱TPA特性参数硬度、弹性、凝聚性、咀嚼性和回复性的影响.研究结果表明,压缩程度对扇贝柱咀嚼性之外的TPA特性参数影响显著,压缩速率对其影响不显著.最终确定扇贝柱的适宜预处理条件为温度70℃,时间12 mi...     

循环周期对Sn3.0Ag0.5Cu/Cu钎焊接头界面化合物的影响

基于自制多场耦合装置,利用准原位观察方法,研究了Sn3.0Ag0.5Cu/Cu焊点在30~125℃热循环过程中不同循环周期下界面金属间化合物微观形貌和生长变化规律。结果表明:随着循环周期的延长,同一位置处的界面化合物的平均厚度是逐渐增加的,且呈抛物线规律。单个扇贝状的Cu6Sn5在纵向方向上先降低后逐渐变大;在横向方向上,随着循环周期的增加,平均宽度一致增加。当热循环周期达到600时,界面金属间化合物的形貌扇贝状转变成层状。     

Effects of Various Geometric Features on the Performance of a 7:1 Pressure Ratio Deeply Scalloped and Split Radial Turbine in a Gas Turbine Engine

A 2 MW gas turbine engine has been developed for the distributed power market.This engine features a 7:1 pressure ratio radial inflow turbine.In this paper,influences of various geometry features are investigated including turbine tip and backface clearances.In addition to the clearances,the effects of the inducer deep scallop and exducer rounded trailing edge are investigated.Finally,geometric features associated with a split rotor(separate inducer and exducer)are studied.These geometry features are investigated numerically using CFD.Part of the numerical results is also compared to experimental data acquired during engine test to validate the CFD results.     

Genetic Differentiation between Natural and Hatchery Stocks of Japanese Scallop (Mizuhopecten yessoensis) as Revealed by AFLP Analysis

Japanese scallop (Mizuhopecten yessoensis) is a cold-tolerant bivalve that was introduced to China for aquaculture in 1982. In this study, amplified fragment length polymorphism (AFLP) markers were used to investigate levels of genetic diversity within M. yessoensis cultured stocks and compare them with wild populations. Six pairs of primer combinations generated 368 loci among 332 individuals, in four cultured and three wild populations. High polymorphism at AFLP markers was found within both cultured and wild M. yessoensis populations. The percentage of polymorphic loci ranged from 61.04% to 72.08%, while the mean heterozygosity ranged from 0.2116 to 0.2596. Compared with wild populations, the four hatchery populations showed significant genetic changes, such as lower expected heterozygosity and percentage of polymorphic loci, and smaller frequency of private alleles, all indicative of a reduction in genetic diversity. Some genetic structures were associated with the geographical distribution of samples; with all samples from Dalian and Japan being closely related, while the population from Russia fell into a distinct clade in the phylogenetic analysis. The genetic information derived from this study indicated that intentional or accidental release of selected Japanese scallops into natural sea areas might result in disturbance of local gene pools and loss of genetic variability. We recommend monitoring the genetic variability of selected hatchery populations to enhance conservation of natural Japanese scallop resources.     

Physical measures of sensory texture in thawed sea scallop meat

An instrumental method of texture measurement for scallop (Placopecten magellanicus) meats after frozen storage has been developed to replace the sensory method. Non-destructive and destructive compressive forces at 50 and 80% deformation respectively and shear peak force gave significant correlation coefficients of 0.89, 0.78 and 0.82 respectively with sensory evaluation of the cooked meats. The coefficient of variation associated with the compression method was smaller, however, than with the shear method.     

扇贝过敏原荧光免疫层析检测方法的构建与应用

目的 构建一种简便、快速、可降低非特异性荧光干扰的时间分辨免疫层析检测方法, 实现快速检测扇贝中原肌球蛋白(tropomyosin, TM)过敏原。方法 本研究采用双抗体夹心免疫层析法, 以含有铕(Eu)纳米微粒的荧光微球作为标签偶联兔抗TM多克隆抗体, 制备荧光探针并对其进行表征。以4 mg/mL兔多克隆抗体作为T线, 羊抗兔免疫球蛋白G (immunoglobulin g, IgG)作为C线组装免疫层析试纸条。结果 本研究组建的试纸条视觉检出限为0.05 μg/mL, 仪器检出限为0.01 μg/mL。试纸条除对虾蟹有交叉反应外, 对其他10余种物种无明显交叉反应。加标样品批内和批间变异系数分别为3.71%~7.94%和12.09%~12.80%, 在不含TM的4种食物基质中加入浓度由低到高的TM, 检测结果与实际加标情况相符。结论 本检测方法准确性良好、灵敏度高、特异性强, 可在多种食物基质中实现对扇贝TM的快速检测。     

扇贝裙边水解液制备海鲜酱的加工工艺

以扇贝裙边为主要原料,选用中性蛋白酶、木瓜蛋白酶和酸性蛋白酶对其进行酶解.然后将水解液浓缩,再配以各种辅料,研制一种营养丰富的新型海鲜酱.其调配比例为:水解液55%、白糖8%、料酒2%、食盐8%、味精0.5%、淀粉4%、老抽酱油4%、辣椒油4%、胡椒粉1.5%、麻油0.5%.     

扇形中深孔爆破块度预测的神经网络法

针对现有爆破块度预测模型存在的不足,应用神经网络理论,研究了具体矿岩条件下的扇形中深孔爆破块度预测的神经网络方法.构建了三层前馈型神经网络结构,并根据扇形中深孔爆破实例,采用BP 算法对网络进行了训练,建立了具体矿岩条件下的扇形中深孔爆破块度分布与其影响因素间的非线性映射关系.采用测试样本对模型进行了测试,结果表明,所建立的模型用于扇形中深孔爆破块度的预测是可行的,模型精度是可靠的.     

栉孔扇贝内脏、裙边油中脂肪酸组成分析

采用索氏提取法对栉孔扇贝内脏和裙边中的油脂进行提取,用气相色谱对其油的脂肪酸组成进行分析测定.结果表明:扇贝内脏油脂含量远远高于扇贝裙边,扇贝内脏油脂含量占70℃烘干样品的14％以上;扇贝内脏和裙边油中不饱和脂肪酸分别为68.10％和55.29％,尤其是(EPA+DHA)含量高,内脏油为44.12％,裙边油为39.77％;扇贝内脏油中(EPA+DHA)含量高于目前报道的各种鱼油的( EPA+ DHA)含量(12％～42％).从扇贝内脏中提取油脂将有较大的市场潜力.