Single step synthesis of GdAlO3 powder

A novel method for preparation of nano-crystalline gadolinium aluminate (GdAlO₃) powder, based on combustion synthesis, is reported. It was observed that aluminium nitrate and gadolinium nitrate exhibit different combustion characteristics with respect to urea, glycine and β-alanine. While urea was proven to be a suitable fuel for direct formation of crystalline α-Al₂O₃ from its nitrate, glycine and β-alanine are suitable fuels for gadolinium nitrate for preparation of its oxide after combustion reaction. Based on the observed chemical characteristics of gadolinium and aluminium nitrates with respect to above mentioned fuels for the combustion reaction, the fuel mixture composition could be predicted that could lead to phase pure perovskite GdAlO₃ directly after the combustion reaction without any subsequent calcination step. The use of single fuel, on the other hand, leads to formation of amorphous precursor powders that call for subsequent calcination for the formation of crystalline GdAlO₃. The powders produced directly after combustion reactions using fuel mixtures were found to be highly sinterable. The sintering of the powders at 1550 °C for 4 h resulted in GdAlO₃ with sintered density of more than 95%. T.D.     

Quantitative measurement of oxygen content in Si targets

Enriched self-supporting targets of ^28,29,30Si are often used in the field of high resolution nuclear physics experiments. The Si targets were prepared by the thermal evaporation deposition or reduction-deposition methods. The targets, however, are always contaminated by oxygen as Si-material is easily oxidised. These contaminated targets lead to poor data with low S/N ratio. Thus it is very useful if one can estimate the amount of oxygen in the target quantitatively before experiments.In this work we have developed a method to estimate the amount of oxygen in the Si target. We used α-ray and β-ray thickness gauges, which have different sensitivity to oxygen atoms. Namely, the α-ray gauge is more sensitive to light elements such as oxygen compared to the β-ray gauge. Thus one can deduce the amount of oxygen by comparing the oxygen thickness measured by α-ray gauge with that of the β-ray gauge.Accuracy of a few percents can be obtained for the oxygen content in Si targets with a thickness of 1 mg/cm². The present method can also be applied to heavy elements such as Ta₂O₅.     

微波热击处理对大豆种子萌发及活力的影响

以大豆（Glycine max）为实验材料,利用统计分析的方法研究了微波热击对种子萌发特性及活力的影响。结果表明：热击处理可提高大豆种子的发芽率,复合微波处理显著促进了芽长和芽活力指数,抑制了电解质渗漏,提高可溶性糖含量和过氧化物酶（POD）活性,萌芽蛋白质含量及氨基酸总量均升高,其中以45℃热击5min及50℃热击2min加微波处理后的大豆芽长、芽活力指数与对照比达极显著水平,蛋白质和氨基酸总量的影响也分别达到显著和极显著水平。同一处理随时间延长,生理效应呈下降趋势。因此,适宜剂量的微波热击复合效应可以促进大豆种子萌发和早期代谢。     

大豆种子萌发过程中子叶细胞超微结构和ATP酶活性动态研究

采用磷酸铅沉淀的电镜细胞化学方法，研究大豆种子萌发过程中，子叶细胞超微结构变化与ATP酶活性的消长。子叶细胞的ATP酶活性主要定位在质膜。在种子萌发的0-3天，子叶细胞贮存蛋白质和油脂大量急剧降解，并快速转运到胚，质膜ATP酶活性较高。萌发的6-9天，子叶细胞内含物大部分消解，蛋白体膜相互融合形成大液泡，原质体开始有稀疏的片层结构，ATP酶活性渐弱至无。萌发第12天，原质体的片层堆叠成基粒，子叶细胞转为同化器官，制造养分，质膜再度呈现较强的ATP酶活性。子叶细胞质膜ATP酶活性反应子叶细胞生理代谢状态。     

大豆低聚糖的制备工艺研究

研究从脱脂豆粕中提取大豆低聚糖的制备工艺。经多次实验,确定了浸提、活性炭脱色和离子交换脱盐等过程的优化工艺参数,并对成品糖浆的成分进行了测定。     

大豆脱皮工艺及其对大豆取油工艺效果的影响

大豆脱皮不仅是大豆浸出取油工艺中生产低温豆粕必要的前处理工序,也应在生产高温饲用豆粕的大豆浸出取油工艺中推广应用。其目的是,提高豆粕的蛋白质含量,增加浸出设备的处理量,降低湿粕的含溶量和残油量,减少生产过程的能量消耗,改善油品质量。     

变性豆粕中蛋白质的酶水解特性的研究

变性豆粕是由大豆浸油后,经高温脱溶所得。本文以高温变性脱脂大豆粕为原料,用正交实验法对变性后在蛋白酶作用下的水解特性进行了深入研究。选用国产1398中性蛋白酶为水解酶对变性豆粕进行水解,研究了变性豆粕中蛋白质溶出率随温度、pH值、时间、底物浓度及用酶量的变化规律,找到了水解变性豆粕的最佳实验条件。为生产实践提供了基础数据,该研究结果对其它蛋白质原料的水解特性研究也具有参考价值。研究结果表明：1398中性蛋白酶水解高温变性豆粕的最佳条件为：温度45℃,时间3h,底物浓度1．0％,用酶量1600u/g,pH值7．0,在此条件下,变性豆粕中蛋白质可有90．71％水解溶出。     

利用豆粕制作保健食品

经过脱脂的大豆粕含有丰富的营养成分及微量活性物质。具有综合利用及开发各种保健品基料的可能性。主要微量活性物有大豆皂甙、大豆低聚糖、大豆异黄酮等,是开发抗衰老、降血脂及预防糖尿病功能食品的最好的原料。也是防治高血脂症、肥胖症、心血管疾病药物有希望开发的药物因子。     

Mg-15．4Gd-1．6Nd合金200℃时效初期的结构分析

本文利用高分辨透射电子显微（HRTEM）技术并结合增强漫散射信息的HRTEM像处理分析方法研究了Mg-15.4Gd-1.6Nd（wt.%）合金200℃时效0.5 h后的结构特征。结果表明,合金时效初期的结构表现为稀土（RE）原子再分布形成的各种局域有序结构,其尺寸很小,一般只有几个nm,处于析出相形成的胚芽阶段。这些结构与传统意义上的β″相（DO19结构）有区别,本文称为β″关联相。在原子层次研究了β″关联相的结构,认为其由单层DO19结构、DO19结构和RE原子聚集三种基本的团簇单元组成。并利用高分辨像模拟法和动力学衍射模拟法进行了计算,结果表明本文建立的结构模型是合理的。     

黄芪甲苷对镉致大鼠支持细胞损伤的保护作用

目的：探讨镉对原代培养大鼠睾丸支持细胞的毒性机制及黄芪甲苷的保护效果。方法：空白对照组、0.5%二甲基亚砜（DMSO）组、镉（50μmol/L）组、镉（50μmol/L）加黄芪甲苷（分别为5、10、20mg/L）组的培养支持细胞用于四甲基偶氮唑盐（MTT）细胞活性实验,DMSO组比较用于验证0.5%DMS0溶剂是否对细...