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11-{[2-(3-Fluorophenyl)ethyl](methyl)amino}pentacyclo[5.4.0.02,6.03,10.05,9]undecan-8-one  [cached]
Samuel D. Banister,Jack K. Clegg,Raphy Hanani,Michael Kassiou
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810038523
Abstract: In the title compound, C20H22FNO, the distances close to the carbonyl and amine are: N—O = 3.232 (4) and N—C = 2.666 (5) . The crystal packing is unremarkable.
五环[5.4.0.02,6.03,10.05,9]十一烷-内-8-醇的合成新方法有机化学  [PDF]
史胜斌, 范桂娟, 杨世源, 李金山, 廖龙渝
有机化学 , 2014, DOI: 10.6023/cjoc201311009
Abstract: 五环[5.4.0.02,6.03,10.05,9]十一烷-内-8-醇是合成抗流感病毒医药、抗发炎药物、高能量燃料和燃料添加剂的关键中间体,本研究以环戊二烯和对苯醌为起始原料,经过Diels-Alder、光环化、羰基保护、氢化铝锂还原、水解、黄鸣龙还原等6步反应合成五环[5.4.0.02,6.03,10.05,9]十一烷-内-8-醇,总产率达44.9%.本方法操作简便,分离纯化容易,成本低廉,收率高,为五环[5.4.0.02,6.03,10.05,9]十一烷-内-8-醇的规模化合成奠定了基础.
五环[5.4.0.02,6.03,10.05,9]十一烷的合成和表征  [PDF]
史胜斌,范桂娟,杨世源,廖龙渝,张红梨,李金山
含能材料 , 2015, DOI: 10.11943/j.issn.1006-9941.2015.02.003
Abstract: 将二聚环戊二烯裂解生成的环戊二烯,与对苯二醌进行Diels-Alder加成反应,得到了1,4,4a,8a-四氢-1,4-桥亚甲基萘-5,8-二酮,经[2+2]环加成和黄鸣龙还原反应,最终得到目标产物五环[5.4.0.02,6.03,10.05,9]十一烷,产物总收率为51.6%,采用熔点测定、核磁共振氢谱、碳谱、红外光谱和质谱对各步产物进行了表征。探讨了Diels-Alder加成和[2+2]环加成反应的影响因素,确定了Diels-Alder加成反应的最佳反应条件:滴加环戊二烯时溶液温度-11℃,时间3h。[2+2]环加成反应的最佳条件是:以丙酮做溶剂,原料浓度2g·125mL-1,光照时间23h。
五环[5.4.0.02,6.03,10.05,9]十一烷/航空煤油复配燃料性能  [PDF]
邱贤平,韦伟,王亚,陈克海,鲁统洁,金凤,叶丹阳
含能材料 , 2015, DOI: 10.11943/j.issn.1006-9941.2015.01.007
Abstract: 五环[5.4.0.02,6.03,10.05,9]十一烷(PCU)是高能量密度笼状碳氢化合物中极有应用潜力的一种化合物,制备的PCU燃烧热值为44.5MJ·kg-1,撞击感度H50大于50cm,I50大于49J,摩擦感度为0,为一类钝感的高能量密度碳氢燃料,将PCU作为高能添加剂和航空煤油RP-3进行二元复配,复配燃料的理化性能研究结果表明:25℃时PCU在航空煤油RP-3中的饱和溶液质量分数为44.6%,当复配燃料中PCU质量分数为25%时,复配燃料的密度较航空煤油RP-3提高7.8%,燃烧热值提高9.5%,复配燃料的闪点从48℃增至49℃,冰点从-59℃降至-62℃。-40℃时复配燃料的粘度在6.99~13.64mm2·s-1之间。在直连式超声速燃烧实验平台上,含10%PCU的复配燃料能进行顺利点火及稳定燃烧,PCU使航空煤油RP-3的超声速燃烧压强从327kPa上升至339kPa。
笼状碳氢化合物五环[5.4.0.02,6.03,10.05,9]十一烷的密度泛函理论研究  [PDF]
邱丽美侯俊先韦伟郑剑贡雪东肖鹤鸣
化学学报 , 2008,
Abstract: 运用密度泛函理论,在B3LYP/6-31G**水平上,对典型高能量密度笼状化合物五环[5.4.0.02,6.03,10.05,9]十一烷(PCU)进行了理论计算。基于上述水平全优化分子结构的键长、键角及二面角求得PCU分子的张力能;用Monte-Carlo方法得到化合物的理论密度;由简谐振动分析求得IR谱,计算结果与实验良好相符;基于振动分析,由统计热力学求得PCU的热力学性质;采用GIAO方法求得PCU的13C-NMR和1H-NMR谱的化学位移,计算结果与实验结果的线性相关性均大于0.99,计算结果可辅助解析PCU的NMR谱。
Bioactivity and Applications of Sulphated Polysaccharides from Marine Microalgae  [PDF]
Maria Filomena de Jesus Raposo,Rui Manuel Santos Costa de Morais,Alcina Maria Miranda Bernardo de Morais
Marine Drugs , 2013, DOI: 10.3390/md11010233
Abstract: Marine microalgae have been used for a long time as food for humans, such as Arthrospira (formerly, Spirulina), and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The present review puts up-to-date the research on the biological activities and applications of polysaccharides, active biocompounds synthesized by marine unicellular algae, which are, most of the times, released into the surrounding medium (exo- or extracellular polysaccharides, EPS). It goes through the most studied activities of sulphated polysaccharides (sPS) or their derivatives, but also highlights lesser known applications as hypolipidaemic or hypoglycaemic, or as biolubricant agents and drag-reducers. Therefore, the great potentials of sPS from marine microalgae to be used as nutraceuticals, therapeutic agents, cosmetics, or in other areas, such as engineering, are approached in this review.
Influence of roadway width and volume to capacity ratio on PCU values
Robert M. BROOKS
Transport Problems : an International Scientific Journal , 2010,
Abstract: The objectives of this paper are to determine the influence of volume to capacity ratio on Passenger Car Unit (PCU) values, speeds of the vehicles and volume of vehicles in PCUs. The limitation of Highway Capacity Manual’s PCU values is ex-plained. Statistical analysis determined that there is a significant difference in volume of cars only between homogeneous and heterogeneous traffic conditions for various road widths. Hence the PCU values of heterogeneous traffic are recommended for the design of traffic systems over homogeneous traffic conditions. The results of the present study shows that for heavy vehicles, SUVs and motorcycles, the PCU values as a function of volume to capacity ratio vary from 0.8 to 2.8, 1.0 to 2.3 and 0.2 to 0.65 respectively. The v/c ratio has a large influence on PCU values as found in this study. Under similar traffic conditions of this study, that exist elsewhere in the country, the values obtained in this study are recommended for use in the analysis and design of traffic engineering facilities.
6-Sulphated Chondroitins Have a Positive Influence on Axonal Regeneration  [PDF]
Rachel Lin,Thomas W. Rosahl,Paul J. Whiting,James W. Fawcett,Jessica C. F. Kwok
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0021499
Abstract: Chondroitin sulphate proteoglycans (CSPGs) upregulated in the glial scar inhibit axon regeneration via their sulphated glycosaminoglycans (GAGs). Chondroitin 6-sulphotransferase-1 (C6ST-1) is upregulated after injury leading to an increase in 6-sulphated GAG. In this study, we ask if this increase in 6-sulphated GAG is responsible for the increased inhibition within the glial scar, or whether it represents a partial reversion to the permissive embryonic state dominated by 6-sulphated glycosaminoglycans (GAGs). Using C6ST-1 knockout mice (KO), we studied post-injury changes in chondroitin sulphotransferase (CSST) expression and the effect of chondroitin 6-sulphates on both central and peripheral axon regeneration. After CNS injury, wild-type animals (WT) showed an increase in mRNA for C6ST-1, C6ST-2 and C4ST-1, but KO did not upregulate any CSSTs. After PNS injury, while WT upregulated C6ST-1, KO showed an upregulation of C6ST-2. We examined regeneration of nigrostriatal axons, which demonstrate mild spontaneous axon regeneration in the WT. KO showed many fewer regenerating axons and more axonal retraction than WT. However, in the PNS, repair of the median and ulnar nerves led to similar and normal levels of axon regeneration in both WT and KO. Functional tests on plasticity after the repair also showed no evidence of enhanced plasticity in the KO. Our results suggest that the upregulation of 6-sulphated GAG after injury makes the extracellular matrix more permissive for axon regeneration, and that the balance of different CSs in the microenvironment around the lesion site is an important factor in determining the outcome of nervous system injury.
USING PCU-CAMEL, A WEB-BASED LEARNING ENVIRONMENT, IN EVALUATING TEACHING-LEARNING PROCESS  [cached]
Arlinah Imam Rahardjo
Jurnal Informatika , 2008,
Abstract: PCU-CAMEL (Petra Christian University-Computer Aided Mechanical Engineering Department Learning Environment) has been developed to integrate the use of this web-based learning environment into the traditional, face-to-face setting of class activities. This integrated learning method is designed as an effort to enrich and improve the teaching-learning process at Petra Christian University. A study was conducted to introduce the use of PCU-CAMEL as a tool in evaluating teaching learning process. The study on this method of evaluation was conducted by using a case analysis on the integration of PCU-CAMEL to the traditional face-to-face meetings of LIS (Library Information System) class at the Informatics Engineering Department of Petra Christian University. Students’ responses documented in some features of PCU-CAMEL were measured and analyzed to evaluate the effectiveness of this integrated system in developing intrinsic motivation of the LIS students of the first and second semester of 2004/2005 to learn. It is believed that intrinsic motivation can drive students to learn more. From the study conducted, it is concluded that besides its capability in developing intrinsic motivation, PCU-CAMEL as a web-based learning environment, can also serve as an effective tool for both students and instructors to evaluate the teaching-learning process. However, some weaknesses did exist in using this method of evaluating teaching-learning process. The free style and unstructured form of the documentation features of this web-based learning environment can lead to ineffective evaluation results
A Novel Power Conditioning Unit (PCU) using Adaptive Signal Processing for Low THD  [PDF]
Debanjan Mukherjee,Asim K. Jana,Malay K. Pandit
International Journal of Engineering and Advanced Technology , 2012,
Abstract: The presence of harmonic in power system is a major concern to power engineers. With the heavy usage of non- linear loads in power systems, the harmonic effect becomes more serious. One of the most popular computation algorithms for harmonic analyzer is Fast Fourier Transform (FFT). In this paper ,single phase current waveform is taken from a three phase supply fed to motor through power analyzer interfaced with PC. FFT is done using MATLAB program on the imported data. After that, same waveform like the current waveform obtained from the hardware setup is created in MATLAB SIMULINK window. That created waveform is filtered by Normalized LMS Filter to reduce Total Harmonic Distortion (THD) in the filtered output. Comparison is done between the hardware results with the software simulated results. THD value is reduced from at max 12.03% to at min 0.17%, which has set a new record to our best knowledge.
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