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1.
利用环己酮与季戊四醇在非酸催化剂的作用下,合成了聚缩酮螺胞二醚的先导化合物7,11,18,21 四氧杂三螺[5,2,2,5,2,2]二十一烷.考察了催化剂、反应物的摩尔比、带水剂、反应温度等对反应的影响.利用FTIR、及HNMR对标题化合物的结构进行了表征,标题化合物的最高收率可达70%以上.  相似文献   

2.
利用苯甲醛与季戊四醇在非酸催化剂的作用下 ,合成了聚缩醛螺胞二醚的先导化合物3,9-二苯基 - 2 ,4,8,1 0 -四氧杂螺 [5 ,5 ]-十一烷 .考察了催化剂、反应物的摩尔比、带水剂、反应温度等对反应的影响 .利用FTIR、TG及HNMR对标题化合物的结构进行了表征 ,产品的最高收率可达 88%以上 .  相似文献   

3.
利用环己酮与季戊四醇在非酸催化剂的作用下,合成了聚缩酮螺胞二醚的先导化合物7,11,18,21.四氧杂三螺[5,2,2,5,2,2]二十一烷.考察了催化剂、反应物的摩尔比、带水剂、反应温度等对反应的影响.利用FTIR、及HNMR对标题化合物的结构进行了表征,标题化合物的最高收率可达70%以上.  相似文献   

4.
利用苯甲醛与季戊四醇在非酸催化剂的作用下,合成了聚缩酝酿螺胞二醚的先导化合物3,9-二苯基-2,4,8,10-四氧杂螺[5,5]-十一烷。考察了催化剂、反应物的摩尔比、带水剂、反应温度等对反应的影响。利用FTIR、TG及HNMR对标题化合物的结构进行了表征,产品的最高收率可达88%以上。  相似文献   

5.
以三氯氧磷、季戊四醇为原料,首先合成螺环磷酸酯二酰氯,然后在螺环磷酸酯二酰氯的基础上合成季戊四醇二磷酸.主要介绍螺环磷酸酯二酰氯和季戊四醇二磷酸的合成工艺及改进方法,并用正交实验找出这两步反应的最优条件.当季戊四醇与三氯氧磷摩尔比为1∶8、温度为90℃、反应时间为10 h时合成的螺环磷酸酯二酰氯(SPDPC)的产率达79.98%.当SPDPC的浓度为0.033 7 mol·L-1、温度为20℃、反应时间为5 h时,合成的季戊四醇二磷酸(SPDPA)的产率达82.03%.同时,用熔点测试仪、红外光谱仪和1H NMR对产物的结构进行表征.  相似文献   

6.
采用季戊四醇与1,3-苯二甲醛为原料,在不同溶剂中合成季戊四醇双缩醛,对影响反应的因素(原料物质的量、催化剂、带水剂)做了研究.利用薄层色谱法(TLC)对反应进行监控,并用红外光谱和核磁共振对产物进行结构表征.  相似文献   

7.
光学纯的1,1′-螺二茚烷-7,7′-二醇与三氟甲磺酸酐反应得到的三氟甲磺酸酯在钯催化剂作用下发生羧甲基化反应生成1,1′-螺二茚烷-7,7′-二羧酸甲酯,进一步水解以大于90%产率得到相应的羧酸.  相似文献   

8.
以芴、溴素为原料,三氯甲烷为溶剂,室温下合成得到2,7-二溴芴,然后以四氢呋喃为溶剂,在叔丁醇钾作用下与卤代烷烃反应合成目标化合物9,9-二烷基-2,7-二溴芴,总收率为56.0-62.4%.通过1H NMR,13CNMR,MS,IR和元素分析确证了2,7-二溴芴与标题化合物的结构.  相似文献   

9.
2,2′,7,7′-四溴-9,9′-螺二芴是合成有机电致发光材料的重要中间体.文章以9,9′-螺二芴为原料,过量的液溴为溴源,无催化剂作用,室温下合成了2,2′,7,7′-四溴-9,9′-螺二芴,产率为63.3%.用核磁共振氢谱对产物进行了结构表征.  相似文献   

10.
本文将4,4’-二环己二酮单缩酮与季戊四醇反应,分别制得化合物3,15-双{8-(1,4-二氧杂螺[4.5]癸烷基)}-7,11,18,21-四氧杂三螺[5.2.2.5.2.2]二十一烷(1)和3,15-聚{7,11,18,21-四氧杂三螺[5.2.2.5.2.2]二十一烷}(2),对其1H-NMR的特征进行了讨论.发现三螺环中(B,C)原季戊四醇中的CH2不裂分,是个单峰;而A、D环上的CH2(H1,H5,H13,H17)受手性轴的影响而裂分成多重峰(如无手性轴的影响应为三峰).表明手性轴对手性的影响主要集中在轴的外侧,对中心影响较小.所获结论对不对称合成中进行手性催化剂和手性固定相的设计具有理论意义.  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.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

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