碳硼烷甲基丙烯酸酯接枝改性真丝研究

以甲基丙烯酸(碳硼烷甲氧乙基)酯为接枝单体,通过自由基乳液接枝处理真丝,在真丝丝素大分子上引入聚甲基丙烯酸(碳硼烷甲氧乙基)酯接枝链.以正交试验方案优选接枝改性工艺条件,得到的最优化工艺条件为:单体质量分数为2.6%、引发剂用量占单体质量分数5%、在pH3的情况下反应100 min.以红外光谱和扫描电镜对接枝前后的真丝进行了结构表征,利用热分析研究了接枝前后真丝的热失重行为.结果表明,接枝处理后真丝耐热性能改善,当接枝率为21.1%时,温度达到300℃时质量保留率为92.2%,高于未处理真丝保留率为89.0%.     

New insight in boron chemistry: Application in two-photon absorption

Two groups of one-dimensional (1D) boron containing two-photon absorbing fluorophores have been prepared and characterized. One group includes boron atoms incorporated in the conjugated or pseudo conjugated central core and the other contain a boron cluster as an acceptor group at one end of the fluorophores. Two boron containing central cores (with two boron atoms) have been explored: the cyclodiborazane and the pyrazabole moieties. The chosen boron cluster, p-carborane, contains 10 boron atoms. All the prepared fluorophores present high two-photon absorption cross-sections. Some water-soluble as well as lipophylic dyes have been prepared and used in bio-imaging.     

First boronization in KSTAR

First boronization in KSTAR is reported. KSTAR boronization system is based on a carborane (C₂B₁₀H₁₂) injection system. The design, construction, and test of the system are accomplished and it is tested by using a small vacuum vessel before it is mounted to a KSTAR port. After the boronization in KSTAR, impurity levels are significantly reduced by factor of 3 (oxygen) and by 10 (carbon). Characteristics of a-C/B:H thin films deposited by carborane vapor are investigated. Re-condensation of carborane vapor during the test phase has been reported.     

先进聚合物可燃毒物燃耗特性分析

针对当前新提出的先进聚合物材料(PACS),分析聚合物可燃毒物的材料特性与慢化特性,基于秦山核电厂与Crystal River Three两类堆型燃料组件,对比分析采用不同类型可燃毒物材料时组件的燃耗特性。结果表明:聚合物材料的慢化特性随含氢量呈线性变化关系,调节聚合物分子组成可以改变毒物的燃耗特性。相对传统的可燃毒物材料,先进聚合物可燃毒物体现了良好的毒物特性,全寿期具有更低的局部功率峰,在燃耗初期PACS聚合物可燃毒物有较低的初始k_(inf)值,而在燃耗后期释放高于1%的k_(inf)值,可燃吸收体核素B-10消耗更加充分,且具有较大的热通量,可提高热中子利用率,并促进裂变核素Pu的消耗。     

一种碳硼烷改性有机硅树脂的制备及其耐热性能

碳硼烷改性有机硅树脂是一种耐热性能优异的高分子材料,具有广阔的应用前景。然而由于聚合单体碳硼烷改性硅氧烷的合成条件苛刻,严重影响碳硼烷改性有机硅树脂的制备和应用。本研究利用羟基与异氰酸酯基间的加成反应,在温和的条件下合成了一种新型结构的碳硼烷改性硅氧烷-碳硼烷改性氨酯桥接丙基三乙氧基硅烷(CBR-Si),在此基础上经水解缩聚反应合成了碳硼烷改性有机硅树脂(CBR-PSQ)。研究结果表明,在二月桂酸二丁基锡的催化作用下,摩尔比为1∶2的1,2-二羟甲基取代碳硼烷(CBR-OH)与异氰酸丙基三乙氧基硅烷(NCO-Si)在60℃下反应12h,可得到CBR-Si。所得有机硅树脂CBR-PSQ具有优异的热稳定性和热氧化稳定性,热分解温度高达500℃,在N₂和空气氛围中800℃的残炭率约为80%。该研究为耐高温碳硼烷改性有机硅树脂的合成和制备提供了一条新途径。     

Carborane Analogues of Fenoprofen Exhibit Improved Antitumor Activity

Fenoprofen is a widely used nonsteroidal anti-inflammatory drug (NSAID) against rheumatoid arthritis, degenerative joint disease, ankylosing spondylitis and gout. Like other NSAIDs, fenoprofen inhibits the synthesis of prostaglandins by blocking both cyclooxygenase (COX) isoforms, COX-1 the “house-keeping” enzyme and COX-2 the induced isoform from pathological stimuli. Unselective inhibition of both COX isoforms results in many side effects, but off-target effects have also been reported. The steric modifications of the drugs could afford the desired COX-2 selectivity. Furthermore, NSAIDs have shown promising cytotoxic properties. The structural modification of fenoprofen using bulky dicarba-closo-dodecaborane(12) (carborane) clusters and the biological evaluation of the carborane analogues for COX inhibition and antitumor potential showed that the carborane analogues exhibit stronger antitumor potential compared to their respective aryl-based compounds.