共查询到19条相似文献,搜索用时 59 毫秒
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三甘醇是具有强烈吸湿性的粘稠液体,被用作石油天然气产品的新型干燥剂及脱水剂,在对三甘醇品质进行评价时,水分的含量是非常重要的指标。本文利用拉曼光谱技术,对三甘醇样品的拉曼光谱图进行采集,三甘醇标准品在波数129cm-1、321cm-1、531cm-1、830cm-1、886cm-1有较强的拉曼信号,以特征波数886cm-1的信号强度与对应的水分含量做标准曲线,得回归方程为y=-42.95x+4583.5,相关系数R2=0.9986,说明拉曼信号强度与三甘醇水分含量有良好的线性关系。选择水分含量为10%、15%、85%、95%的三甘醇溶液作为回测,平均回收率在90.1%~115.86%,相对标准偏差在0.43%~10.1%,该方法可准确检测三甘醇中的水分含量,且快速、操作简便、样品用量少,可用于现场检测。 相似文献
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微波消解-电感耦合等离子体-质谱法测定大米中的铅、镉、汞和砷 总被引:3,自引:0,他引:3
应用微波消解-电感耦合等离子体-质谱法(ICP-MS)一次进样同时测定大米中的铅、镉、汞、砷含量.采用8mL硝酸+2mL过氧化氢的微波消解体系,消解后无需赶酸,定容后直接用ICP-MS测定.实验发现,运用该方法干扰少,速度快,多元素同时分析,重现性好,准确度高.该方法的回收率分别为:Pb:100.9%、Cd:90.1%、Hg:86.1%、As:92.8%.Pb、Cd、Hg、As方法检出限均为0.001ng/mL. 相似文献
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含稳定氮氧自由基聚磷酸酯的合成及其弛豫性能研究 总被引:4,自引:1,他引:3
通过二氮磷酸-O-(1-氧-2,2,6,6,-四甲基-4-哌啶醇)酯分别与四甘醇、三甘醇、二甘醇、1,6-己二醇、1,8-辛二醇、N-乙基二乙酰胺、N-正丁基二乙酰胺缩聚,制得七个含稳定氮氧自由基(TEMPO)的聚磷酸酯.对这些新的聚磷酸酯进行了结构表征,并测试了部分聚合物的纵向弛豫性能. 相似文献
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用溶胶-凝胶法制备的离子液体键合固相微萃取(SPME)涂层,采用顶空固相微萃取与气相色谱法(HS-SPME-GC)测定水中邻苯二甲酸酯(PAEs).优化了固相微萃取的实验条件.方法的检测限为0.0005-0.0500μg/L,线性范围在0.01-100μg/L.用该法测定了东湖水样、自来水及桶装水中PAEs的含量,邻苯二甲酸二丁酯的含量在1.10-3.10μg/L,其他3种未检出.东湖水样的加标回收率为81.0%-98.6%,相对标准偏差(RSD)为3.2%-9.2%. 相似文献
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荧光光谱法辨别丙二醇和二甘醇 总被引:2,自引:0,他引:2
以齐药二厂的假药事件为背景,对1,2-丙二醇、1,3-丙二醇和二甘醇的吸收光谱和荧光光谱进行了测量,实验结果证明光谱法不失为一种快捷有效的区分手段.在紫外吸收光谱中,可以通过最大吸光度的差异区分二甘醇和丙二醇;在一定紫外波长激励下,三种醇的荧光光谱特性均存在差异,以此可以对三种醇作出有效区分;在230nm激发下,将二甘醇和两种丙二醇分别混合,混合溶液的相对荧光强度均与两种丙二醇体积比呈线性反比关系,这在一定程度上证明了二甘醇的荧光量子效率大于两种丙二醇. 相似文献
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Hua Yan Cheng Peng Wenjuan Liu Hu Zhou Wei Wang 《Journal of Macromolecular Science: Physics》2017,56(5):315-323
Polyurethane (PU) hydrogels with good hydrophilicity and biocompatibility have been applied as biomedical materials. A series of polyurethane prepolymers based on methylene diphenyl diisocyanate (MDI), polycaprolactone (PCL) and polyethylene glycol (PEG), using diethylene glycol (DEG) as the chain-extender, were synthesized; then the polyurethane hydrogels were obtained from the prepolymers using benzoyl peroxide (BPO) as a cross-linker by free radical polymerization. The influences of the ratio of polyols (PCL and PEG) on the contact angle, swelling ratio and morphology of the polyurethane hydrogel were investigated. The loading capacity and release behavior of chloramphenicol from the PCL-PEG/MDI/DEG hydrogels with different compositions were also studied. The contact angle and swelling degree results showed that the PCL-PEG/MDI/DEG hydrogel with PCL/PEG mass ratio of 3:1 had higher hydrophilicity than that with PCL/PEG mass ratios of 1:1 and 1:3. All PCL-PEG/MDI/DEG hydrogels showed three dimensional porous structures; however, the pore size increased with increasing PEG content. The chloramphenicol release kinetics from PCL-PEG/MDI/DEG hydrogels indicated Fickian diffusion, and the drug release rate increased with increasing PEG content in the PU hydrogels. 相似文献
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Xiaofei Li Hua Yan Wenjuan Liu Yunhui Zhao Tianlong Huang 《Journal of Macromolecular Science: Physics》2019,58(3):442-451
Designing and fabricating nanocomposite scaffolds based on biodegradable polymers and bioactive materials are an important topic in the area of bone regeneration. A novel nanocomposite scaffold composed of polyurethane (BPU) and nano-bioactive glass (NBAG) was prepared. The effects of the NBAG content on the properties of the BPU/NBAG composite scaffolds, including the morphologies, porosity and compressive strength, were investigated. The BPU/NBAG composite scaffolds showed an interconnected pore structure with the pore size ranging from 50 to 500?μm for all samples. The porosity percent and swelling ability decreased with increasing NBAG content; however, the compressive strength was enhanced. 相似文献
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The Raman spectrum of ethylene glycol was studied as a function of temperature in the neat liquid and at two concentrations in the solvent, DMSO. Relative intensities of the gauche C-C-O bending mode and the C-C stretch (coincident for both rotamers) were utilized to calculate δH and TδS for each of the mixtures. It was observed that dilution in the solvent stabilizes the trans conformer, whereas variation in the entropy difference appears to favor the gauche form. 相似文献
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以乙二醇作为溶剂 ,氢氧化钠 (1mol· L-1)、氯化锌 (1mol· L-1)为原料 ,在非水体系中 ,15 0℃温度下化学沉淀法制备纳米级氧化锌粒子 ,反应时间为 2 h。用 XRD、FT- IR、TG- DTA、TEM表征粒子的结构和特征 ,德拜 -谢乐公式计算粒子的平均粒径。在实验条件下 ,前驱体生成与氧化锌粒子形成同步实现 ,粒子粒径为 2 0 nm左右 ,其表面被有机物包覆。 相似文献