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1.
纳米固体酸催化聚合松香酯化反应的研究   总被引:3,自引:0,他引:3  
研究了纳米氧化锌、纳米氧化铈、纳米二氧化钛、纳米氧化镧、氧化钆、氧化钐、氧化钕、SO42-/ZrO2、活性氧化锌、纳米氧化镁催化剂,催化聚合松香与甘油酯化反应的催化性能.结果表明:催化剂的活性顺序为氧化钕>纳米氧化锌>氧化钐>氧化钆>纳米氧化镧>纳米二氧化钛>纳米氧化镁纳米氧化铈活性氧化锌SO42-/ZrO2.采用纳米氧化锌催化聚合松香与甘油反应的适宜条件为:纳米氧化锌用量为聚合松香质量的2%,甘油的用量为聚合松香质量的28%,酯化温度265℃,反应时间5 h.聚合松香的酯化率≥95.4%,产物的酸值≤7 mg/g(KOH),软化点≥99℃,加纳色阶为6~7.  相似文献   

2.
以歧化松香为原料,经过胺化法提纯得到脱氢枞酸,继而与乙二醇进行双酯化反应,制备了脱氢枞酸乙二醇双酯.在单因素实验的基础上,利用正交实验、响应面软件对合成工艺条件进行研究,探讨了反应温度、反应时间、酸醇比、催化剂种类及用量,带水剂二甲苯用量等诸因素对反应酯化率的影响,得出最佳反应条件:n(脱氢枞酸):n(乙二醇)=2.37:1,对甲苯磺酸5%,二甲苯20ml,反应温度250℃,反应时间8.0h,酯化率达到99%左右.  相似文献   

3.
强酸性阳离子交换树脂催化合成甘油三乙酸酯的研究   总被引:2,自引:1,他引:1  
以乙酸、甘油为原料,直接酯化合成甘油三乙酸酯,研究了反应温度、反应时间、原料配比、带水剂、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成甘油三乙酸酯的最佳工艺条件是:反应温度92~98℃;反应时间5h;n(乙酸):n(甘油)为4.5:1.0;催化剂用量为总物料质量的0.9%;带水剂苯用量为15mL(甘油为0.15mol的情况下)。甘油三乙酸酯的收率达到92.30%。催化剂不经处理可循环使用多次。该催化剂具有价廉易得、催化活性好、不腐蚀设备、无环境污染等优点。  相似文献   

4.
以磷钨酸和磷钨酸铝为催化剂,用乳酸和正丁酸合成了乳酸正丁酯.研究了催化剂用量、醇酸物质的量比、反应时间和反应温度等因素对产率的影响.结果表明磷钨酸和磷钨酸铝对乳酸和正丁醇的酯化反应具有较好的活性,在适当条件下,乳酸具有较高的酯化率.  相似文献   

5.
采用正丁基吡啶硫酸氢盐离子液体为催化剂,对棕榈酸和甲醇催化酯化合成棕榈酸甲酯的影响因素进行了研究.试验结果表明:棕榈酸物质的量比为50∶1、反应温度为70 ℃、催化剂用量为6%和反应时间为110 min时酯化率最高,在此基础上进行了正交试验极差分析,各因素对反应酯化率的影响主次顺序为:催化剂用量>反应时间>反应温度>醇酸摩尔比,反应的最佳条件是:催化剂用量为8%,反应时间为130 min,反应温度为70 ℃,醇酸物质的量比为50∶1,在此最优条件下进行验证试验,通过验证试验可测得酯化率为98.63%.根据试验数据进行方差分析表明,反应时间、反应温度、醇酸摩尔比和催化剂用量4个因素的水平变化对酯化率均无显著影响.  相似文献   

6.
通过正交试验方案系统地考察了催化剂用量、醇 酸物质的量比、反应时间以及反应温度等因素对酯化反应的影响 ,确定了酯化反应的最佳工艺条件 ,讨论了不同催化剂的催化活性对酯收率的影响以及催化剂的重复使用  相似文献   

7.
以固体超强酸SQ2-/TiO2-SiO2为催化剂合成柠檬酸三丁酯,考察了醇酸摩尔比、催化剂用量、反应时间、反应温度及催化剂重复使用对酯化反应的影响.结果表明酯化反应的最佳条件为酸醇摩尔比为15.4,催化剂用量为反应物总质量的0.94%,反应时间为6小时,反应温度为130℃,此条件下酯化率可达93.4%.该催化剂具有制备简便,与产品分离容易,不易腐蚀设备,重复使用后仍保留良好的活性等优点.  相似文献   

8.
马来松香丙烯醇酯聚合物的制备及表征   总被引:1,自引:0,他引:1  
以松香为原料,通过3步反应,首次制得马来松香丙烯醇酯聚合物,探讨了酯化反应和聚合反应的最佳条件,对酯化产物进行了紫外、红外分析和酸值的测定;对聚合物进行了差热分析,软化点和分子量的测定.通过实验可以得出,酯化反应最佳条件为:马来松香与丙烯醇的物质的量之比为1∶3.5,催化剂的质量为马来松香的6.5%,反应时间5小时,最高温度为135℃;聚合反应最佳条件为:马来松香丙烯醇酯20克,三氯化铝3克,温度为75℃,反应时间4小时,所得产物容易分离纯化,最佳条件下所得酯化产物酸值99.7,酯化产率达96.3%;聚合物软化点240℃,平均分子量2632,聚合产率92.5%.  相似文献   

9.
利用低温方法制备了S2O82-/TiO2固体超强酸催化剂,研究了该催化剂在乙酸和异戊醇酯化反应中的催化活性和稳定性.观察了焙烧温度、(NH4)2S2O8溶液浸渍浓度对催化剂催化性能的影响,以及催化剂用量、醇酸比、反应时间、反应温度等因素对酯化率的影响.结果表明:在450~500℃焙烧和用1.00mol/L的(NH4)2S2O8浸渍所得的S2O82-/TiO2对酯化反应具有良好的催化活性,反应的最佳醇酸摩尔比为1.2:1,催化剂用量为反应物料总量的1.0%,反应时间1.5h,反应温度110~120℃,酯化率可达95%.  相似文献   

10.
韦藤幼  陀雄信 《广西科学》2004,11(2):118-120
利用硫酸作催化剂,在微波加热与共沸精馏分水联合的新型酯化反应装置中合成松香丁酯。最佳反应条件为:正丁醇与松香的摩尔比为6:1、催化剂用量为松香用量的6%、反应时间为120min,微波功率为607.5W。粗产品酸值为52mgKOH/g,产率为92%。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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