螺旋藻水溶性多糖的分离纯化

螺旋藻干粉经乙醇脱脂后用水提取,乙醇沉淀,并经凝胶Ｓｅｐｈａｄｅｘ－Ｇ柱层析精制,获得４种螺旋藻制多糖ＳＰＡ－１,ＳＰＡ－２,ＳＰＡ－３,ＳＰＡ－４,研究表明均为均一多糖组分。     

Sagnac干涉仪中差分相位调制的单光子干涉

介绍一种稳定的长距离单光子干涉仪，即光纤Sagnac单光子环形干涉仪，其平衡结构有效地补偿了由于光纤长度随时间缓变带来的相位涨落和光纤本身形状随时间缓变引起的偏振态涨落．在Sagnac环形干涉仪中通过分时相位调制实现了1550nm波长27km单光子干涉，对比度大于90％．进一步的讨论表明该单光子干涉仪可用于长距离稳定的单光子路由和量子保密通信．     

2,3-二氯-6-羧酰氯喹啰啉活性染料反应活性及“染料-纤维”键的稳定性

对２,３－二氯－６－羧酰氯喹啉类活性染料的反应活泼性以及“染料－纤维”键的稳定性进行了反应动力学研究,测定水解速度常数;与其他类型活性染料进行比较,对此类活性染料性能进行了评价。     

QUALITATIVE ANALYSIS FOR A THIRD-ORDER DIFFERENTIAL EQUATION IN A MODEL OF CHEMICAL SYSTEMS

In this paper a mathematical model of chemical systems is investigated.We present the conditions for the existence and local stability of the steady statesand the periodic solution of the Hopf type.Specifically,we show by using an ana-lytical method that there may exist two or four Hopf bifurcation points separatedat a finite distance from each other;at the same time,a technique for studying theHopf bifurcation value is given.     

海芋多糖的研究

海芋用去离子水煮提,乙醇沉淀,Sevage法去蛋白,并经凝胶柱层析精制,获得均一的海芋多糖;用紫外可见光谱仪测定海芋中多糖的含量;凝胶层析法测定海芋多糖的平均相对分子质量;酸水解、高效液相色谱分析海芋多糖的单糖组成;红外光谱测定糖残基的连接方式.结果表明海芋中多糖质量分数为0.74%,海芋多糖的平均相对分子质量为26 400,主要由葡萄糖(97.3%)通过β-糖苷键连接而成.     

怎样让小学生爱上阅读

阅读与现实生活息息相关，阅读教学也是小学语文教学中不可缺少的一环。但是有很多学生不愿意阅读，怎样才能让学生爱上阅读，主动参与阅读呢？应该从三个方面来解决。     

Rapid solidification of acoustically levitated Al-Cu-Si eutectic alloy under laser irradiation

Al-27%Cu-5.3%Si ternary eutectic alloy was melted using a YAG laser and then solidified while being acoustically levitated. A maximum undercooling to 195 K (0.24 TL) was achieved with a cooling rate of 76 K/s. The solidification microstructure was composed of (Al+θ+Si) ternary eutectics and (Al+θ) pseudobinary eutectics. During acoustic levitation, the (Al+θ+Si) ternary eutectics are refined and the (Al+θ) pseudobinary eutectics have morphological diversity. On the surface of the alloys, surface oscillations and acoustic streaming promote the nucleation of the three eutectic phases and expedite the cooling process. This results in the refinement of the ternary eutectic microstructure. During experiments, the reflector decreases with increasing alloy temperature, and the levitation distance always exceeds the resonant distance. Because of the acoustic radiation pressure, the melted alloy was flattened, and deformation increases with increasing sound pressure. The maximum aspect ratio achieved was 6.64, corresponding to a sound pressure of 1.8×104 Pa.     

DNA damage stress induces the dissociation of Smurf1/2 from MDM2 in a slow manner

The tumor suppressor p53 locates at the key point of cell growth or apoptosis balance, and the expression level of p53 is tightly controlled by ubiquitin ligases including MDM2. Upon DNA damage stresses, p53 was accumulated and activated, leading to cell cycle arrest or apoptosis. We previously showed that Smad ubiquitylation regulatory factor 1/2 (Smurf1/2) promotes p53 degradation by interacting with and stabilizing MDM2, and consequently enhancing MDM2-mediated ubiquitylation of p53. However, it is uncle...     

合成有机磷腈化合物的新方法

卤化磷腈化合物(PNX_2)_3是有用的无机化合物,它具有耐高温,不燃烧等特点。但是,由于氯化磷腈化合物中的磷—氯键的存在,对水分特别敏感,因而,在潮湿的空气中不能稳定存在。近些年来,有机合成化学工作者,用有机基团取代了氯化磷腈中的氯原子,形成有机磷腈化合物,它既能耐高温,不燃烧,同时在潮湿的空气中能稳定存在。近几年来,由有机磷腈单体聚合所形成的有机磷腈聚合物有了新的发展。目前,这种新型材料使用于军事目的方面发挥着重要的作用,因此,引起人们的注意。     

Gastric vagal afferent inputs reach the glycemia-sensitive neurons of lateral hypothalamic area in the rat

The lateral hypothalamic area (LHA) is one of the most important central areas in the regulation of feeding behavior[1]. The glycemia-sensitive neurons within the LHA sense the blood glucose level and subsequently trig-ger various visceral and somatic responses for maintaining the homeostasis of blood glucose concentration. Some electrophysiological studies have demonstrated that the gastric vagal afferent inputs could reach the LHA in the cat[2,3], but the studies did not reveal whether th…