共查询到20条相似文献,搜索用时 62 毫秒
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为了解决天然气水合物降压分解过程中孔隙尺度精细描述的难题,开展了天然气水合物微观可视模型实验设计。实验装置设计从具备可视功能、实时监测功能、数据处理功能和临界状态判断功能入手,开展了设备初始化调试、生成与分解模拟和产气效率分析等共3个层次实验内容。实验结果表明,学生不但能够定性描述水合物微观孔隙水合物生成与分解过程,而且实现了定量计算不同时刻水合物产气效率,这为学生对水合物微观生成与降压分解规律的理解奠定了基础。实验加深了学生对海洋油气工程专业知识的理解,提升了学生解决复杂工程问题的实践能力。 相似文献
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《Macromolecular rapid communications》2017,38(11)
Epoxy polymers (EPs) derived from soybean oil with varied chemical structures are synthesized. These polymers are then cured with anhydrides to yield soybean‐oil‐derived epoxy thermosets. The curing kinetic, thermal, and mechanical properties are well characterized. Due to the high epoxide functionality per epoxy polymer chain, these thermosets exhibit tensile strength over an order of magnitude higher than a control formulation with epoxidized soybean oil. More importantly, thermosetting materials ranging from soft elastomers to tough thermosets can be obtained simply by using different EPs and/or by controlling feed ratios of EPs to anhydrides.
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超声提取正相高效液相色谱法测定大豆及大豆油中的磷酸甘油酯 总被引:3,自引:0,他引:3
建立了超声提取-固相萃取纯化/正相高效液相色谱测定大豆及大豆油中磷脂酰胆碱(PC)、磷脂酰乙醇胺(PE)、磷脂酰肌醇(PI)的方法。考察了提取溶剂、超声功率、超声时间、提取温度及净化方式的影响,并研究了不同色谱固定相对磷酸甘油酯分离效果的影响。优化的实验条件为:以氯仿-甲醇(2∶1,体积比)为提取溶剂,1 500 W功率超声提取30 min;氨基固相萃取柱为纯化小柱;正己烷-异丙醇-1%HAc(8∶8∶1,体积比)为流动相。在该条件下,PC、PE、PI的线性范围分别为0.08~8.00、0.15~15.00、0.30~20.00 g.L-1,定量下限分别为0.021、0.050、0.060 g.L-1,检出限在8~23 mg.L-1之间,其在大豆和大豆油中的回收率为85%~108%。日内与日间精密度分别不大于4.7%和8.6%。 相似文献
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在无溶剂条件下制备环氧蓖麻油,对参加环氧化反应的有机酸和催化剂进行选择,研究了反应时间和反应温度对产物环氧值的影响。通过正交实验对环氧化合成条件进行优化,结果表明,蓖麻油/乙酸/双氧水/磷酸(质量比)=1:0.15:0.8:0.01,反应温度50℃,反应时间3h,所得产品环氧值达6.95%,采用FT-IR和1HNMR方法对产品进行了表征。整个过程操作简单,反应时间短,反应条件温和。 相似文献
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S. M. Ashraf Sharif Ahmad Ufana Riaz Manawwer Alam H. O. Sharma 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1409-1421
Blending is a useful technique to improve upon the physico‐mechanical properties of the polymers. Synergies of the properties of the two polymers occur best when they are miscible or compatible with each other. Vegetable oil epoxy can be used for blending with polymers to improve upon their physical and mechanical properties. Poly(methacrylic acid) (PMAA) is a hard, brittle and water sensitive material. Dehydrated castor oil epoxy (DCOE), a product from a sustainable resource, has been chosen to improve upon the physical and mechanical properties of PMAA through solution blending. Blends of DCOE/PMAA were prepared in the weight ratios 80/20, 60/40 and 20/80 through a solution method by mixing in dimethyl sulphoxide. In the first instance, the miscibility of the two components was investigated using the techniques of viscosity and ultrasonic measurements. The study revealed that the two components showed semicompatibility/semimiscibility in solution. The compatibility in the solid phase was examined by differential scanning calorimetry and scanning electron microscopy which revealed that DCOE–PMAA pair were incompatible in solid phase. 相似文献
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溴苯制取实验的绿色化设计 总被引:1,自引:1,他引:0
液溴与苯在铁粉催化下的反应非常剧烈,反应容器的温度很高,常规条件下即使使用洗气瓶也仍然有大量溴蒸气以及苯蒸气溢出;另外,由于苯和液溴都易挥发,而试剂的取用以及产物的分离操作都是在敞口条件下进行的,也会不可避免地造成苯与溴的挥发泄漏,污染十分严重。因此,中学化学教师基本上都不做该演示实验了。笔者对此实验重新进行了绿色化设计,利用一次性注射器、输液器、粉针瓶和普通小药瓶做实验仪器,实现了实验过程的全封闭操作,解决了污染问题,收到了很好的效果。 相似文献
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采用酸性氧化铝做催化剂对蓖麻油(CO)进行环氧化,探索环氧化反应时间、反应温度和催化剂等不同条件对蓖麻油环氧化的影响,从而优化出合适的反应条件,采用傅立叶变换红外光谱法(FTIR)、热重分析法(TG)对制备的环氧化蓖麻油(ECO)的结构和性质等进行了研究。利用盐酸-丙酮法对环氧化产物进行环氧值的测定,结果表明,在优化条件下,即采用酸性氧化铝做催化剂,H2O2的滴加温度保持在50~55 ℃,反应温度65 ℃,反应时间控制在11.5 h,同时同时加入尿素做稳定剂,可以提高H2O2的利用率,使环氧化蓖麻油的环氧值达到2.094×10-3 mol/g。 对ECO的性能表征结果表明,ECO粘度随着环氧值的增大而增大,随着温度的升高而降低。 ECO在250 ℃前能够基本保持稳定,而后开始分解,有3个明显的热分解阶段:250~390 ℃、390~470 ℃、470~580 ℃,ECO的热稳定性较好。 相似文献
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S. M. Ashraf Sharif Ahmad Ufana Riaz Manawwer Alam H. O. Sharma 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1115-1120
Blending of two polymers in solution is a simple and cost effective technique to improve upon the physical and mechanical properties of the component polymers. Maximum synergism in the properties of the two polymers occurs when they are thermodynamically miscible. Poly(vinyl alcohol) (PVA) yields tough, flexible and water sensitive films. Linseed oil epoxy(LOE), a product from sustainable resource, used as a plasticizer and corrosion resistant coating, does not produce free standing film. A blend of PVA with LOE may yield films of good toughness and flexibility, and low water absorption if the two components are miscible with each other. Blends of PVA with LOE were prepared in weight ratios 80/20, 60/40, 40/60 and 20/80 through solution method by mixing in dimethyl sulphoxide. In the first instance, the miscibility the two components were investigated using the techniques of viscosity and ultrasonic measurements. The study revealed that the two components showed miscibility up to below 60 wt% PVA in the blend as at the composition LOE: PVA 40/60, phase inversion occurs. Above this composition, immiscibility is indicated; differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) delineates the above behavior in the solid phase. 相似文献