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1.
纳米固体超强酸S2O82-/ZrO2催化的β-蒎烯异构化反应   总被引:2,自引:1,他引:1  
主要研究了纳米固体超强酸S2O8^2-/ZrO2催化的β-蒎烯异构化反应,实验结果表明,该催化剂具有很高的催化活性和选择性.异构化反应的主产物是莰烯,副产物主要是苧烯、蒈烯、三环烯、α-松油烯和对异丙基甲苯等.异构化反应的最佳条件是:反应温度70℃,反应时间4 h,催化剂用量为β-蒎烯质量的3%.在此最佳条件下,β-蒎烯转化率为100%,莰烯选择性为61.90%.  相似文献   

2.
本文用气相色谱、气相色谱—质谱—计算机、红外光谱等方法研究了牡荆挥发油的化学成分。在已分析的116个成分中鉴定了其中的26个化合物,占总量的96.53%。它们是α—蒎烯,莰烯,桧烯,β—蒎烯,α—水芹烯,对一伞花烃,1,8—按叶油素,β—水芹烯,芳樟醇,橙花醛,香叶醛,乙酸龙脑酯,β—榄香烯β—石竹烯,α—和β—愈创木烯,δ—及α—榄香烯,β—金合欢烯,环氧石竹烯,橙花叔醇,石竹烯醇—1,金合欢醇,β—按叶油醇,β—甜没药醇以及柏木脑。其中β—石竹烯含量达39.55%。  相似文献   

3.
以强酸性阳离子大孔交换树脂Lewatit2620为催化剂,催化α-蒎烯水合反应,获得主要产物α-松油醇.在催化反应中,部分α-蒎烯发生异构化反应,生成单环萜烯,影响松油醇的收率.在搅拌釜反应器内分别考察了催化剂种类、溶剂种类、催化剂用量、反应物配比、温度及反应时间对α-蒎烯转化率和α-松油醇收率的影响.结果表明,优化反应条件为:催化剂用量为每克总液体炉料使用催化剂0.20g,m(α-蒎烯)∶m(水)∶m(溶剂y)=1∶0.13∶2,反应温度333.15K,反应时间4h,此时α-蒎烯转化率为98%,松油醇的收率为36%.本文建立拟均相(PH)模型来研究α-蒎烯直接水合反应的动力学,并估算出动力学参数,通过模型得到的计算值与实验值是吻合的,故PH模型适用于α-蒎烯的直接水合反应.用准一级动力学模型确定了各反应的反应速率常数的表达式.  相似文献   

4.
<正> 在林产化学工业,如合成樟脑和一些香料的生产中,需要某些萜烯类物质二元体系的汽液相平衡数据及关联式。关于这方面的工作,国内尚未见报道,国外也仅有少数文献报道,而且不免有粗糙之处(例如文献[4]中所报道的α-蒎烯~苧烯二元系汽液平衡数据)。作者正在对常见的萜烯类物质进行汽液平衡数据的测定,并用Wilson方程关联。本文首先介绍作者应用改进的Rose平衡釜(以下简称Rose釜)测得的在111mmHg(绝压)下α-蒎烯~苧烯二元体系的汽液平衡数据。  相似文献   

5.
四方蒿挥发油化学成分及应用研究   总被引:3,自引:0,他引:3  
采用G-MS-DC联用方法,测定和鉴定了四方蒿精油的化学成分,其主要成分为蛇麻烯(12.02%)。β-蒎烯(11.98%),异蒎莰酮(10.03%),石竹烯氧化物(6.27%),檀萜烯(4.28%),叶绿醇(8.12%)等45个化合物,其中有31个成分为首次从四方蒿中检出。  相似文献   

6.
在“110”阳离子交换树脂上载上钼的非均相催化剂,用烃基过氧化氢为氧化剂,对环己烯,苧烯,α-蒎烯,β-蒎烯和莰烯进行环氧化反应的研究。用叔丁基过氧化氢为氧化剂转化为环氧化物相应为99.8,82.5,80.9,71.9和50.6%;用异丙苯过氧化氢为氧化剂转化为环氧化物相应为77.4,77.1,71.2,69.2和35.6%。  相似文献   

7.
本文研究了以α-蒎烯和马来酸酐(MA)为原料合成萜烯马来树脂的工艺.α-蒎烯与马来酸酐的摩尔比为1.05~1.1:1,反应温度150~170℃,反应时间16~20h,产率可达90%以上.  相似文献   

8.
通过减压精馏的方式富集了废轮胎热解油的轻质馏分,并通过常压精馏的方式将轻质馏分分为6段,系统地研究了甲苯、乙苯、二甲苯、对伞花烃和柠檬烯等高价值物质的分布情况;随后使用乙二醇-环丁砜作为二元萃取剂针对柠檬烯富集馏分进行提纯研究.结果表明:甲苯主要分布在100~120℃馏段,乙苯和二甲苯主要分布在120~140℃馏段,柠檬烯和对伞花烃主要分布在160~180℃馏段.柠檬烯提纯方面,在20℃,乙二醇与环丁砜的质量比为3∶1,剂与油的质量比为5∶1的条件下对柠檬烯富集馏分进行10级萃取实验,可完全去除非烃类杂质,芳香烃杂质的质量分数下降至24.99%,柠檬烯的质量分数从33.81%提升至48.03%,柠檬烯萃取提纯的效果优于精馏提纯的效果.  相似文献   

9.
固体超强酸SO4^2-/ZrO2催化α-蒎烯异构反应   总被引:5,自引:0,他引:5  
研究了固体超强酸SO2-4/ZrO2催化剂的制备条件(硫酸浸渍浓度、焙烧温度等)对其催化性能的影响.结果表明,催化剂的制备条件不同,对莰烯选择性和α-蒎烯转化率有较大影响.适宜的催化剂制备条件是 硫酸浓度0.5~1.0 mol/L,焙烧温度650 ℃.对所制备的SO2-4/ZrO2固体超强酸作为α-蒎烯异构反应的催化剂,以及对影响反应过程的主要因素进行探讨.优化的工艺条件为反应时间1~3 h,反应温度(130±2)℃,催化剂质量分数3%~4%.该条件下α-蒎烯转化率96.4%,莰烯选择性49.7%.此外,还分析了催化剂放置时间对异构产物的影响及催化剂重复使用情况.  相似文献   

10.
研究了固体超强酸SO2-4/ZrO2催化剂的制备条件(硫酸浸渍浓度、焙烧温度等)对其催化性能的影响.结果表明,催化剂的制备条件不同,对莰烯选择性和α-蒎烯转化率有较大影响.适宜的催化剂制备条件是: 硫酸浓度0.5~1.0 mol/L,焙烧温度650 ℃.对所制备的SO2-4/ZrO2固体超强酸作为α-蒎烯异构反应的催化剂,以及对影响反应过程的主要因素进行探讨.优化的工艺条件为:反应时间1~3 h,反应温度(130±2)℃,催化剂质量分数3%~4%.该条件下α-蒎烯转化率96.4%,莰烯选择性49.7%.此外,还分析了催化剂放置时间对异构产物的影响及催化剂重复使用情况.  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
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   

19.
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   

20.
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   

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