脱氧塑胶的制备与性能研究

以抗坏血酸、改性铁粉为脱氧剂制备聚乙烯醋酸乙烯酯脱氧塑料 ,研究了脱氧剂对脱氧塑胶脱氧与拉伸机械性能的影响。结果表明添加脱氧剂 MFe、Vc或 MFe和 Vc的 EVA脱氧塑胶脱氧能力较好 ,而且使用方便。     

Synthesis of chloromethylstyrene‐tetraethyleneglycol dimethacrylate copolymer beads having various phenolic derivatives immobilized via amide bond and their antioxidation activity

Resins having phenolic derivatives were prepared by treating a resin (RAS‐4G), having benzylamino groups, with benzoic acids containing phenolic hydroxyl groups. The RAS‐4G was prepared by treating macroreticular chloromethylstyrene‐tetraethyleneglycol dimethacrylate (4G) copolymer beads with potassium phthalimide in N,N‐dimethylformamide, followed by reflux in an ethanol/hydrazine monohydrate mixture. 4‐Hydroxy benzoic acid, (2,4‐, 3,4‐, and 3,5‐)dihydroxy benzoic acids, 3,4,5‐trihydroxy benzoic acid, etc., were used as benzoic acids with phenolic hydroxyl groups. The antioxidation ability of the resins having phenolic derivatives was investigated against the generation of 1,4‐dioxane hydroperoxide. The resins showed high inhibition ability against the generation of hydroperoxide. In particular, the resin (RAS‐4G‐3,4‐DHBA) having two phenolic hydroxyl groups had the highest inhibition ability. The resins were found to act as radical scavengers during the generation of 1,4‐dioxane hydroperoxide by UV irradiation in the presence of oxygen. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2097–2104, 2005     

基于Py-GC/MS研究热解反应中自由基的捕获反应

在500℃下对类煤模型化合物1-萘甲醇与同位素示踪剂的共热解进行了机理研究。利用Py-GC/MS进行快速产物检测,同时联合自由基捕获剂来推断自由基的反应过程。结果表明,在500℃和0.2 min的条件下,1-萘甲醇的热解产物相对单一,但是自由基反应的引发、交换和湮灭极其快速,现有检测方法是对某一时间节点的平衡反应结果的分析。通过D₂O和H₂¹⁸O同位素示踪,成功捕获到了自由基交换后的D取代产物和¹⁸O取代产物。揭示了1-萘甲醇经过1-萘甲基自由基转化为1-萘甲醛的转化过程,发现萘环上的取代基在1-萘甲醇的热解过程中起着重要作用。同时对自由基及产物进行了定性和半定量分析,发现在加入自由基捕获剂后产物的丰度较之前降低了一个数量级,说明了自由基捕获剂抑制了产物的生成。     

吸氧性PET果汁饮料瓶的制备及性能研究

将吸氧剂与聚对苯二甲酸乙二醇酯(PET)共混制得吸氧性PET橙汁饮料瓶。利用扫描电子显微镜、容器透氧仪对共混材料的结构与性能进行测定;利用高效液相色谱和色差仪对瓶装橙汁的质量进行检测。结果表明,吸氧剂能有效提高PET瓶的阻氧性能,减缓橙汁中维生素C的氧化速度,保证其色泽鲜亮,口感纯正。     

辉钼矿直接氢还原工艺的热力学研究

对三种无SO2污染的辉钼矿氢还原生产金属钼路线进行了热力学分析。不用固硫剂,辉钼矿直接氢还原反应是很难进行的。用CaO做固硫剂,辉钼矿氢还原反应是可以进行的,随着温度的升高氢气利用率逐渐增加。用Na2CO3做固硫剂,辉钼矿氢还原反应的产物通过水洗可以得到纯金属钼粉。氢气利用率随着温度的升高与压力的下降而增加。     

提高金银浮选回收率的试验研究

对赤峰某金矿进行提高金银浮选回收率的试验研究,通过XRD/SEMEnergy Spectrum对样品的物相组成、金银赋存状态及嵌布粒度进行检测;考察了磨矿细度、捕收剂及辅助剂用量、扫选时间及矿浆pH值对浮选效果的影响;通过精选实验、开路综合条件试验和闭路试验研究,结果表明,浮选时加入T12,抑制细泥及硫化氧化矿,产出精矿中Au品位可达60.2g/t,浮选回收率可达87.50%;精矿中Ag品位可达6 767 g/t,浮选回收率可达到75.21%,确定适宜该矿石性质的工艺条件及工艺流程,获得的金精矿可作为混合精矿外售。     

Hyperglycemia Induces Inflammatory Response of Human Macrophages to CD163-Mediated Scavenging of Hemoglobin-Haptoglobin Complexes

Hyperglycemia, a hallmark of diabetes, can induce inflammatory programming of macrophages. The macrophage scavenger receptor CD163 internalizes and degrades hemoglobin-haptoglobin (Hb-Hp) complexes built due to intravascular hemolysis. Clinical studies have demonstrated a correlation between impaired scavenging of Hb-Hp complexes via CD163 and diabetic vascular complications. Our aim was to identify whether hyperglycemia is able to amplify inflammation via Hb-Hp complex interactions with the immune system. M(IFNγ), M(IL-4), and control M0 macrophages were differentiated out of primary human monocytes in normo- (5 mM) and hyperglycemic (25 mM) conditions. CD163 gene expression was decreased 5.53 times in M(IFNγ) with a further decrease of 1.99 times in hyperglycemia. Hyperglycemia suppressed CD163 surface expression in M(IFNγ) (1.43 times). Flow cytometry demonstrated no impairment of Hb-Hp uptake in hyperglycemia. However, hyperglycemia induced an inflammatory response of M(IFNγ) to Hb-Hp1-1 and Hb-Hp2-2 uptake with different dynamics. Hb-Hp1-1 uptake stimulated IL-6 release (3.03 times) after 6 h but suppressed secretion (5.78 times) after 24 h. Contrarily, Hb-Hp2-2 uptake did not affect IL-6 release after 6h but increased secretion after 24 h (3.06 times). Our data show that hyperglycemia induces an inflammatory response of innate immune cells to Hb-Hp1-1 and Hb-Hp2-2 uptake, converting the silent Hb-Hp complex clearance that prevents vascular damage into an inflammatory process, hereby increasing the susceptibility of diabetic patients to vascular complications.     

Investigation on photogenerated radicals of some carboxylates in solution and in aqueous dispersions of AgBr

Abstract

The photogenerated free radicals from formate, oxalate and acetate in aqueous solutions without and with dispered AgBr grains under illuminations of 355 nm laser light, natural light and monochromatic red, green or blue light were detected by electron spin resonance with spin-trap DMPO. The results showed that: (a) ·CO₂^? radicals were produced in the formate solution by all of these illuminations; (b) the signals of ·CO₂^? radicals were greatly intensified when an AgBr dispersion was present in the formate solution; (c) the signals of ·CO₂^? radicals in the oxalate solution were also detected and intensified when an AgBr dispersion was present, but only after illumination by the 355 nm laser; (d) ·CH₃ radicals, instead of ·CO₂^?, were weakly detected in the acetate solution, but only in the presence of AgBr under illumination by the 355 nm laser. The photochemical behaviour of these carboxylates, particularly formate and oxalate, perhaps implies their capability for trapping photogenerated holes and their potential for acting as a hole converter to an effective electron carrier.     

以斑马鱼为模式生物的辐射效应修饰剂研究

利用斑马鱼作为模式生物,进行一系列的实验研究,尤其在胚胎发育、基因表达、药物筛选和疾病模型方面有其独特的优势。但它被应用于辐射效应修饰剂的研究时间较短,已有的文献显示发展前景良好。本工作就近些年以斑马鱼为模式生物研究的辐射效应修饰剂进行概述,主要涉及如氨磷汀、DF-1、AG1478、Flavopiridol和一些DNA损伤修复蛋白。