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聚酯生产中皂化值测定方法的改进 被引量:1
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作者 陈利兴 《合成纤维》 CAS 北大核心 2008年第1期30-32,共3页
将测定酯化产物皂化值的吡啶/水溶剂改为正丙醇/乙二醇溶剂,克服了吡啶/水溶剂的刺激、腐蚀性,同时也改善了溶剂自身方面对测试结果带来的不利影响,提高了分析的稳定性及准确性。实践证明:正丙醇/乙二醇溶剂能完全满足测试要求,并降低... 将测定酯化产物皂化值的吡啶/水溶剂改为正丙醇/乙二醇溶剂,克服了吡啶/水溶剂的刺激、腐蚀性,同时也改善了溶剂自身方面对测试结果带来的不利影响,提高了分析的稳定性及准确性。实践证明:正丙醇/乙二醇溶剂能完全满足测试要求,并降低了测试成本。 展开更多
关键词 皂化 酯值
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无甲醛封端型水性聚氨酯整理剂的合成工艺
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作者 施建刚 田呈呈 +1 位作者 杨少艳 赵振河 《西安工程大学学报》 CAS 2013年第6期736-739,共4页
采用封端法,以聚醚二元醇(F6)、异佛尔酮二异氰酸酯(IPDI)等为主要原料,以亚硫酸氢钠为封闭剂制备封端型水性聚氨酯(WPU).通过探讨异氰酸酯指数(R值)、预聚温度、预聚时间、封端剂、封端温度和封端时间等多种因素对封端型水... 采用封端法,以聚醚二元醇(F6)、异佛尔酮二异氰酸酯(IPDI)等为主要原料,以亚硫酸氢钠为封闭剂制备封端型水性聚氨酯(WPU).通过探讨异氰酸酯指数(R值)、预聚温度、预聚时间、封端剂、封端温度和封端时间等多种因素对封端型水性聚氨酯的影响,得到了合成封端型水性聚氨酯的最佳工艺:抽真空脱水温度130°左右,2h;预聚反应65°,3h;R值2.0;封端温度0~5℃;封端系数2.0;封端时间3min. 展开更多
关键词 封端型 水性聚氨(WPU) 异氰酸指数(R)
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三(2─甲基─2─苯基丙基)锡苯氧乙酸酯化合物的^(13)CNMR研究
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作者 贺庆林 包明 +1 位作者 田作林 刘宝殿 《波谱学杂志》 CAS CSCD 1996年第3期297-302,共6页
测定了15种三(2─甲基─2─苯基同基)锡苯氧乙酸酯化合物的13CNMR谱,利用模型化合物对比及化学位移计算比较等方法.对全部谱线进行了归属.讨论了化合物13CNMR谱与结构的关系.求得对苯环碳的取代基化学位移参数(... 测定了15种三(2─甲基─2─苯基同基)锡苯氧乙酸酯化合物的13CNMR谱,利用模型化合物对比及化学位移计算比较等方法.对全部谱线进行了归属.讨论了化合物13CNMR谱与结构的关系.求得对苯环碳的取代基化学位移参数(SCS):Cipso=30.0,Cortho=-13.8,Cmeta=0.8,Cpara=-7.5. 展开更多
关键词 ^(13)CNMR 三(2─甲基─2─苯基丙基)锡苯氧乙酸.取代基化学位移
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PGFE对农用膜无滴性的影响 被引量:2
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作者 周立国 任春芳 +2 位作者 窦莹 张建英 王玉兵 《现代塑料加工应用》 CAS 北大核心 2009年第1期40-42,共3页
研究了聚甘油硬脂酸(PGFE)酯作为流滴剂使用时其羟值、酯值、酸值对农用膜无滴性的影响,并且对聚甘油的聚合度与无滴性之间的关系进行了探讨。结果表明:PGFE的羟值为350、酯值为148、酸值小于3时农用膜无滴性好。
关键词 聚甘油硬脂酸 酯值 无滴性 农用膜
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微晶蜡非催化氧化反应的神经网络模型 被引量:1
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作者 冯玉海 沈本贤 高晋生 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第1期55-58,共4页
对微晶蜡进行了非催化空气氧化 ,并利用人工神经网络将氧化微晶蜡的酸值、酯值及微晶蜡的氧化条件 (反应温度、空气流量和反应时间 )进行关联 ,建立了微晶蜡非催化氧化的酸值、酯值的神经网络模型 ,并用该模型预测了反应条件对微晶蜡氧... 对微晶蜡进行了非催化空气氧化 ,并利用人工神经网络将氧化微晶蜡的酸值、酯值及微晶蜡的氧化条件 (反应温度、空气流量和反应时间 )进行关联 ,建立了微晶蜡非催化氧化的酸值、酯值的神经网络模型 ,并用该模型预测了反应条件对微晶蜡氧化反应过程的影响。结果表明 ,该模型不但具有较高的计算精度 。 展开更多
关键词 微晶蜡 神经网络模型 非催化氧化反应 酯值 反应条件 反应过程
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Effect of processing parameters on bulge-forming Polycarbonate parts 被引量:1
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作者 侯珍秀 吴菁 +2 位作者 刘智 李晓东 王仲仁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期54-58,共5页
According to the data of the experiment made in mechanical tensile of Polycarbonate in high temperature, experiments were done to polycarbonate sheet by hot gas pressure bulge-forming. It was found that selecting and ... According to the data of the experiment made in mechanical tensile of Polycarbonate in high temperature, experiments were done to polycarbonate sheet by hot gas pressure bulge-forming. It was found that selecting and combination of the processing parameters were vital to the quality. In the experiments and numerical simulation with the software of DYNAFORM, the processing parameters have been studied.The results showed that the method of discontinuous pressure and pressure preservation advantage the forming; when temperature and pressure meet the forming conditions, the longer time of pressure preservation promotes sufficient forming. 展开更多
关键词 orocessing PARAMETER hot gas pressure bulge-forming PC sheet parts quality
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Synthesis,algal inhibition activities and QSAR studies of novel gramine compounds containing ester functional groups 被引量:2
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作者 李霞 于良民 +2 位作者 姜晓辉 夏树伟 赵海洲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第2期309-316,共8页
2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its ... 2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its analogues with other ingredients in antifouling paints, structural modification of TBG was focused mainly on halogen substitution and N-substitution. Two halogen-substitute gramines and their derivatives which contain ester functional groups at N-position of gramines were synthesized. Algal inhibition activities of the synthesized compounds against algae Nitzschia cIosterium were evaluated and the Median Effective Concentration (EC50) range was 1.06-6.74 lag ml^-1. Compounds that had a long chain ester group exhibited extremely high antifouling activity. Quantitive Structure Activity Relationship (QSAR) studies with multiple linear regression analysis were applied to fred correlation between different calculated molecular descriptors and biological activity of the synthesized compounds. The results show that the toxicity (log (I/EC50)) is correlated well with the partition coefficient log P. Thus, these products have potential function as antifouling agents. 展开更多
关键词 gramine derivative SYNTHESIS algal inhibition activity QSAR
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Surface effects on in-shoe plantar pressure and tibial impact during running 被引量:4
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作者 Weijie Fu Ying Fang +3 位作者 David Ming Shuo Liu Lin Wang Sicong Ren Yu Liu 《Journal of Sport and Health Science》 SCIE 2015年第4期384-390,共7页
Purpose: This study aims to explore the effects of running on different surfaces on the characteristics of in-shoe plantar pressure and tibial acceleration. Methods: Thirteen male recreational runners were required ... Purpose: This study aims to explore the effects of running on different surfaces on the characteristics of in-shoe plantar pressure and tibial acceleration. Methods: Thirteen male recreational runners were required to run at 12 km/h velocity on concrete, synthetic track, natural grass, a normal treadmill, and a treadmill equipped with an ethylene vinyl acetate (EVA) cushioning underlay (treadmill_EVA), respectively. An in-shoe plantar pressure system and an accelerometer attached to the tibial tuberosity were used to record and analyze the characteristics of plantar pressure and tibial impact during running. Results: The results showed that there were no significant differences in the 1 st and 2nd peak plantar pressures (time of occurrence), pressure-time integral, and peak pressure distribution for the concrete, synthetic, grass, and normal treadmill surfaces. No significant differences in peak positive acceleration were observed among the five tested surface conditions. Compared to the concrete surface, however, running on treadmillEVA showed a significant decrease in the 1st peak plantar pressure and the pressure time integral for the impact phase (p 〈 0.05). These can be further ascribed to a reduced peak pressure observed at heel region (p 〈 0.05). Conclusion: There may not be an inevitable relationship between the surface and the lower-limb impact in runners. It is, however, still noteworthy that the effects of different treadmill surfaces should be considered in the interpretation of plantar pressure performance and translation of such results to overground running. 展开更多
关键词 Peak plantar pressure Pressure distribution Running Surface Tibia acceleration
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Micron-sized Magnetic Polymer Microspheres for Adsorption and Separation of Cr(VI) from Aqueous Solution 被引量:1
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作者 王强 官月平 +2 位作者 刘翔 杨明珠 任秀峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第1期105-110,共6页
The magnetic poly-(methacrylate-divinyl benzene) microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr(VI) from aqueous solution by magnetic poly-(MA-DVB) ... The magnetic poly-(methacrylate-divinyl benzene) microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr(VI) from aqueous solution by magnetic poly-(MA-DVB) microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr(VI) adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature. 展开更多
关键词 magnetic poly-(MA-DVB) microsphere surface amino group chromium adsorption adsorption condition
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Instability Mechanisms of Supported Liquid Membrane for Phenol Transport 被引量:6
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作者 郑辉东 王碧玉 +1 位作者 吴燕翔 任其龙 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期750-755,共6页
The instability mechanisms of the supported liquid membrane using Celgard 2500 membranes as support and tributyl phosphate dissolved in kerosene as carrier for phenol transport was studied by ele.etroehemical impedanc... The instability mechanisms of the supported liquid membrane using Celgard 2500 membranes as support and tributyl phosphate dissolved in kerosene as carrier for phenol transport was studied by ele.etroehemical impedance spectroscopy. Emulsion formation is demonstrated to be one of the main causes for the instability of supported liquid membrane in the present system. The emulsion-facilitated conditions, such as higher membrane liquid concentration, faster stirring speed, lower salt concentration and higher HLB value, would accelerate the degradation of supported liquid membrane. Other mechanisms including solubility and osmotic pressure work together to increase the membrane liauid loss. 展开更多
关键词 supported liquid membrane PHENOL instability mechanisms emulsion formation
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Diagnostic Value of Hepatic Enzymes, Triglycerides and Serum Proteins for the Detection of Hepatic Lipidosis in Chelonoidis carbonaria in Captivity
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作者 Gustavo Henrique Pereira Dutra 《Journal of Life Sciences》 2014年第8期633-639,共7页
Hepatic lipidosis is a common lesion in chelonians and may be related with vitellogenesis, hyperparathyroidism, follicular stasis, fatty diets or lacking nutrients, sedentary life and obesity, bacterial toxins in live... Hepatic lipidosis is a common lesion in chelonians and may be related with vitellogenesis, hyperparathyroidism, follicular stasis, fatty diets or lacking nutrients, sedentary life and obesity, bacterial toxins in liver and starvation. Clinical signs are unspecific. Routine biochemical tests don't have specificity and it is better defined through biopsy. The objective was evaluated the biochemical hepatic profile of red footed tortoises (Chelonoidis carbonaria) with the histopathological findings of lipidosis by laparoscopic biopsy. Samples of blood were collected for biochemistry of thirty-six animals from two different groups, twenty animals from a zoo and sixteen from a breeder. The animals were submitted to liver biopsy by videolaparoscopy. Three fragments were collected, two of them were processed by histology and one went to electron microscopy. Nineteen tortoises from the zoo had lipidosis in laparoscopy and macrovesicular degeneration. Fifteen tortoises from the breeder had microvesicular degeneration. The diagnosis of steatosis was confirmed by electron microscopy. There was no statistical difference of aspartate aminotransferase levels between the two groups; however there was significant difference of triglycerides levels. The enzymatic activity of transaminases is not related to the histological grading of lipidosis in tortoises, however triglycerides levels are higher in animals with more severe gradation. 展开更多
关键词 BIOPSY STEATOSIS LIVER Chelonoidis enzymes.
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Kinetics of the decomposition of dimethylhexane-1,6-dicarbamate to1,6-hexamethylene diisocyanate 被引量:3
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作者 Yan Cao Huiquan Li +1 位作者 Ningbo Qin Ganyu Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第5期775-779,共5页
The kinetics of the decomposition of dimethylhexane-1,6-dicarbamate to 1,6-hexamethylene diisocyanate was studied. A consecutive reaction model was established and the reaction orders for the two steps were confirmed ... The kinetics of the decomposition of dimethylhexane-1,6-dicarbamate to 1,6-hexamethylene diisocyanate was studied. A consecutive reaction model was established and the reaction orders for the two steps were confirmed to be 1 and 1.3 by the integral test method and the numerical differential method, respectively. The activation energies of the two steps were (56.94 4±5.90) kJ·mol^-1 and (72.07±3.47) kJ·mol^-1 with the frequency factors exp( 12.53±1.42) min^- 1 and ( 14.254±0.84) tool^-0.33. L^0.33·min^-1, respectively. Based on the kinetic model obtained, the progress of the reaction can be calculated under given conditions. 展开更多
关键词 Kinetics 1 6-Hexamethylene diisocyanate Decomposition Dimethylhexane-1 6-dicarbamate
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Probing the pH-dependent chain dynamics of poly(acrylate acid) in concentrated solution by using a cationic AIE fluorophore 被引量:1
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作者 ZHANG Shuang YAN JiMing +2 位作者 QIN AnJun SUN JingZhi TANG Ben Zhong 《Science China Chemistry》 SCIE EI CAS 2013年第9期1253-1257,共5页
We report a novel strategy to study the chain dynamics of poly(acrylic acid) (PAA) in a relative concentrated solution (1.0 g/L). The strategy is based on the fluorescent probe (DCTPE) with unique aggregation-induced ... We report a novel strategy to study the chain dynamics of poly(acrylic acid) (PAA) in a relative concentrated solution (1.0 g/L). The strategy is based on the fluorescent probe (DCTPE) with unique aggregation-induced emission (AIE) characteristics. Free DCTPE molecules are non-emissive in aqueous solution, but they become highly emissive when trapped in polymer coils. The fluorescence intensity is proportional to the efficiency of trapping DCTPE molecules in polymer coils. By correlation the change of fluorescence intensity with the variation of pH value (from 1.78 to 12.06), the PAA chain's dynamics in the relatively concentrated solution have been elucidated into three processes. In the pH range from 12.06 to 6.0, PAA chains take an extended and non-folding conformation. Changing pH from 6.0 to 3.86, PAA chains are partially protonated and loosely packed polymer coils are formed. Further lowering the pH value of the solution (from 3.86 to 1.78), protonated segments dominate the PAA chains, and at the same time, the intermolecular hydrogen bonding takes effect, thus the polymer chains posses in the conformation of more compact coils. 展开更多
关键词 POLYELECTROLYTE polymer dynamics coils concentrated solution aggregation-induced emission
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