Separation and Characterization of Bisphenol-A Epoxy Resin Paint

[中文文摘]介绍了双酚 A型环氧树脂涂料配方的剖析方法。通过 IR及 NMR等方法对纯化的环氧树脂进行了表征并与传统的化学滴定测环氧值方法比较 ,用 NMR法测定双酚 A型环氧树脂数均相对分子质量的方法 ,建立了数均相对分子质量与环氧值之间的关系。[英文文摘]A separation method for bisphenol A epoxy resin paint was reported, and epoxy resin was characterized by IR and NMR spectroscopy.In contrast to traditional chemical titration method of measuring epoxy value( E ), the number average relative molecular mass ( n) of bisphenol A epoxy resin was calculated in terms of integral intensity in NMR. The relation of E and n was also given

2,2′-Bipyridine and Malononitrile as Additives for Styrene Living Radical Polymerization

[中文文摘]研究了稳定自由基存在下苯乙烯的活性聚合。发现在 2 ,2′ 联吡啶的存在下 ,苯乙烯聚合的分子量控制效果提高 ,分子量可控 ,分子量分布较窄。在与丙二腈共同作用时 ,可在 4h内达到 85 %的转化率 ,分子量分布在 1 .5以下 ,分子量控制误差在 2 0 %以下。设计分子量在 1 0 ,0 0 0 90 ,0 0 0 ,实测分子量和理论分子量相近.[英文文摘]Living free radical polymerizations of styrene were studied using benzoyl peroxide as an initiator in the presence of TEMPO(2,2,6,6-tetramethylpiperidinyl-1-oxy). The effect of MN/bpy malononitrile/2,2′-bipyridine additives on the control of molecular weight is explored. It was found that styrene polymerization was distinctly accelerated by MN/bpy additives and the theoretic molecular weight tallie well with the experimental molecular weight. Using the additives in a 1∶1.2 molar mixture of BPO and TEMPO with molbpy∶mol TEMPO = 2∶1 , molMN ∶mol TEMPO = 2. 5 at 135 ℃, the conversion of the styrene polymerization reached 85 % , the polydispersitics is below 1.5 and the difference between the theoretic molecular weight and the experimental molecular weight was cont roled below 20 %.固体表面物理化学国家重点实验室基金资助项目 (1130

Experimental study on reperfusion of intraocular lens

作者简介: 祁明信, 男, 1945 年7 月 出生, 教授、主任医师、博士研究生 导师, 主要从事白内障的基础与临 床研究。联系电话: 0591-83570887; E-mail:qihuang@netease. com 通讯作者: 黄秀榕,E-mail:[email protected][中文文摘]目的开展晶状体再灌注的离体和动物实验研究,并对再灌注人工晶状体技术进行评价。方法采用新鲜离体幼兔眼、离体猪眼、新西兰白兔眼,应用自行研制的人工晶状体材料,进行以下实验:(1)体外固化实验;(2)晶状体前囊膜微型撕囊及其稳固性实验;(3)经微型前囊膜开口超声乳化吸出晶状体内容物实验;(4)活的新西兰白兔眼内人工晶状体再灌注实验。结果(1)按硅酮聚合物与固化剂50:1的比例可获得柔软、弹性好、固化时间短(完全固化时间为60min)的注入材料;(2)晶状体前囊膜1.8～2.0mm的连续环形撕囊口具有较好的稳定性,可经该微型开口吸出晶状体内容物并灌注材料;(3)超声能量18%、流量25mL·min-1、负压120mmHg(1kPa=7.5mmHg)为晶状体内容物经微型前囊膜开口吸出的最佳条件;(4)注入灌注材料后可形成由晶状体囊膜包裹的、置换原晶状体皮质和核的、新的再灌注人工晶状体。结论采用再灌注人工晶状体的方法可进行新型人工晶状体再灌注,可为治疗白内障和老视提供参考。[英文文摘]Objective To carry out the experimental study on reperfusion of intraocular lens(IOLs) in vitro or in animal,and to assess the technique of IOLs reperfusion.Methods The following experiments were performed by using self-developed materials in fresh rabbit eyes and pig eyes in vitro,as well as in eyes of alive New-Zea-land rabbits:(1)Solidification study of self-developed material in vitro;(2)Continuous circular capsulorhexis(CCC) in anterior capsule of lens and its stability;(3)Draw of lens contents via phaco through mini-CCC;(4)IOLs ref illing in the eyes of alive New-Zea land rabbits. Results(1) Thematerialwhich was soft, springy and short-term solidification(full solidification time was 60 minutes) were obtained in certain proportion of geland solidified agent(50:1) in vitro; ( 2)The CCC in anterior capsule of lens with 1.8-2.0 mm diameter had very good stability. The lens contents were drawn and the materialwere refilled through themini-CCC; (3) The best conditions of drawing out lens contents through m ini-CCC were phaco energy 18% , flow 25 mL·min- 1, and negative pressure 120 mmH g (1kPa=7.5 mmHg);(4) The new refilled IOLs, which were wrapped by capsule of lens and were replaced original cortex and nucleus of lens, were obtained after thematerial refillied. Conc lusion. New IOLs are refilled through this method, which can prov ide reference for the treatment of cataract and presbyopia.福建省科技三项费用;教育厅重点资助项目基金资助(编号:K98041

高超声速二维湍流分离流传热特性的实验研究

一、前言 高超声速流的分离再附问题,尤其是湍流边界层分离,引起了国内外气动研究工作者的广泛兴趣。为了解湍流分离再附区的基本流动机理和建立半经验的估算方法,国外在简单的平板-楔二维模型上进行了大量的实验研究,积累了很多实验资料,建立了一些经验关系式。但这些实验大都在楔角小于45度的模型上进行的。内斯特勒等人虽对平板-前向台阶模型测量了台阶前分离区的热流分布,但台阶面上只测得两三个位置的

四象限InGaAs APD探测器的研究

文章中设计的四象限InGaAs雪崩光电二极管（Avalanche Photo Diode,APD）的管芯结构采用正入光式平面型结构,而材料结构采用吸收区、倍增区渐变分离的APD结构,在对响应时间、暗电流和响应度等参数进行计算与分析的基础上,优化了器件结构参数。试验结果表明,其响应时间≤1.5 ns,响应度≥9.5 A/W,暗电流≤40 nA,可靠性设计时使PN结和倍增层均在器件表面以下,可有效抑制器件表面漏电流,提高器件的可靠性

Research on Variety of Soil Organic Nitrogen Components in Artificial Herbage Land on Loess Plateau

黄土区人工牧草地 18年苜蓿连作对土壤耕层水解总氮、氨态氮、氨基酸氮及氨基糖氮含量有很大影响 ,不施肥条件下苜蓿连作能明显增加土壤耕层水解总氮、氨基酸氮和氨基糖氮含量。连续施 P处理根层水解总氮、氨态氮、氨基酸氮和氨基糖氮含量分别比对照增加 4 13.5 5 m g/ kg、5 8.39mg/ kg、16 9.83m g/ kg和 10 7.0 1mg/ kg;NPM处理土壤耕层水解总氮与对照相比增加 192 .5 8mg/ kg、氨基酸氮增加 2 2 3.4 4 mg/ kg、氨基糖氮增加 2 5 .6 6 m g/kg,而氨态氮含量则大幅度降低 ;在 6 0～ 10 0 cm不同处理的各形态氮含量接近且随土层加深逐渐减少。粮草轮作系统中不同苜蓿生长年限对土壤的水解总氮、氨态氮和氨基酸氮含量有增加的作

The Variation of Soil Nutrients of Long-term Fertilization Artificial Grassland in Soil Profiles

苜蓿连作长期施 P或施 NPM均能增加土壤耕层的有机碳、全氮和碱解氮含量。长期施 NPM对提高整个土壤剖面内的有机碳含量也有显著作用 ,而长期施 P仅能改善土壤耕层有机碳含量 ,对耕层以下土壤的有机碳含量则有降低作用 ;粮草轮作系统中 ,随苜蓿生长年限的增加 ,整个土壤剖面的有机碳含量均有一定程度的提高 ,二、四年生苜蓿土壤的有机碳含量明显高于一年生苜蓿土壤 ,土壤有机碳和全氮的在土壤剖面呈典型的“S”型分布 ,土壤剖面全氮和碱解氮含量变化与有机碳变化有很好的相关性