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本文对用二氧化硒氧化α-蒎烯制备桃金娘烯醛进行了研究,探讨了氧化剂、溶剂、反应时间和反应温度的影响。发现活化处理后的二氧化硒,可以明显提高反应的选择性,当产品的收率从45%提高到61%,产品的纯度提高到96%,硒的回收率达到70%。 相似文献
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以α-蒎烯为原料、SeO2为氧化剂,选择性氧化双键α-氢合成了桃金娘烯醛.通过IR、GC—MS对其结构进行了表征。优化了合成反应条件.并对其生物活性进行了测试。结果表明,在反应温度为(60±5)℃、反应时间为6~7h、SeO2与α-蒎烯摩尔比为1:(2~3)、氧气流量约为1000mL·Min。的条件下.所制得的桃金娘烯醛产率较高,α-蒎烯的选择转化率相对稳定。桃金娘烯醛对云南纵坑切梢小蠹有一定诱集作用,其诱集率梢转干期(71.6%)明显高于梢转梢期(46.2%)。 相似文献
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以α-蒎烯为原料合成一种重要的化工中间体桃金娘烯醛,对其合成反应器进行了模拟设计。得出了数学模型方程。并对方程的解编写了计算程序,为放大提供了理论基础。 相似文献
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以α-蒎烯(Ⅰ)为原料,经选择性烯丙位甲基氧化反应制备了桃金娘烯醛(Ⅱ),Ⅱ再经缩合反应得到了桃金娘烯醛缩氨基硫脲(Ⅲ),进一步氧化环化得到了桃金娘烯醛基噻二唑(Ⅳ),然后与系列酰氯化合物进行N-酰化反应,以66%~81%的收率合成得到了11个桃金娘烯醛基噻二唑-酰胺化合物Ⅴa~k。采用FTIR、1HNMR、13CNMR和ESI-MS对目标化合物进行了结构表征,并测试了目标化合物的抑菌和除草活性。结果表明:在化合物Ⅴa~k的质量浓度为50 mg/L时,Ⅴa~k对测试的苹果轮纹病菌、黄瓜枯萎病菌、花生褐斑病菌、小麦赤霉病菌和番茄早疫病菌均显示不同程度的抑菌活性,其中桃金娘烯醛基噻二唑-乙酰胺(Ⅴa)、桃金娘烯醛基噻二唑-氯乙酰胺(Ⅴb)和桃金娘烯醛基噻二唑-正丙酰胺(Ⅴc)对苹果轮纹病菌的相对抑制率分别为93.0%、93.0%和98.2%,化合物Ⅴb对黄瓜枯萎病菌的相对抑制率为84.3%,表现出与阳性对照嘧菌酯(对苹果轮纹病菌和黄瓜枯萎病菌的相对抑制率分别为96.0%和87.5%)相当的抑菌活性。构效分析表明:脂肪族取代基衍生物表现出更好的抑菌活性。此外,在质量浓度为100 mg/L时,化合物Ⅴc对油菜胚根生长的相对抑制率为79.6%,显示出比阳性对照丙炔氟草胺(抑制率为63.0%)更好的除草活性。 相似文献
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以α-蒎烯为原料合成一种重要的化工中间体桃金娘烯醛 ,对其合成反应器进行了模拟设计 ,得出了数学模型方程 ,并对方程的解编写了计算程序。为放大提供了理论基础 相似文献
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Fe_2O_3-V_2O_5/Al_2O_3催化氧化α-蒎烯制备桃金娘烯醛的研究 总被引:2,自引:0,他引:2
用不同的方法制备了Fe2O3-V2O5/Al2O3催化剂,用BET、TPD表征了催化剂的表面积和O2吸附性能,并考察了催化剂的制备方法对α-蒎烯合成桃金娘烯醛活性和选择性影响,结果表明,均匀沉淀法制备的催化剂具有较大的比表面积,较多表面氧活性中心和较高的催化活性和选择性,同时用均匀沉淀法制备的催化剂考察了α-蒎烯合成桃金娘烯醛的工艺条件,其最佳条件为:催化剂用量5%、反应温度80℃、反应时间240min,在此条件下,α-蒎烯转化率84.9%,桃金娘烯醛选择性78.4%。 相似文献
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α-蒎烯-马来酸酐加成物的合成 总被引:5,自引:0,他引:5
在DLB催化下,α-蒎烯经异构同时和马来酸酐发生Diels-Alder反应制备1-异丙基-4-甲基二环-5-辛烯-2,3-二酸酐(TMA)。运用正交试验法研究了影响合成TMA的主要因素:反应温度、催化剂种类、催化剂用量、反应时间,并确立其最佳合成条件:催化剂用量3%(以α-蒎烯的质量计),反应温度145℃,反应时间1.0 h,(反应物α-蒎烯与马来酸酐摩尔比为1.4:1)。TMA的收率达88%以上,纯度达92%以上,并明显缩短了反应时间。此外,利用红外光谱、薄层色谱、气相色谱和GC-MS等方法对TMA进行了分析和表征。 相似文献
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The synthesis and electrochemistry of acetylacetonatolanthanide(III)phthalocyaninates are reported. Two new kinds of lanthanide complexes Li[Pc]Ln(acac)2] and (Pc)Ln(acac) were obtained where Ln is the trivalent ions of Eu, Gd, Dy, Tb, Ho, Er, Tm, Lu, and Pc is the dianion of phthalocyanine and acac is the acetylacetonate anion. These complexes were characterized by infrared and electronic absorption spectroscopy. An overall oxidation reduction mechanism at a platinum electrode in dimethyl sulfoxide is presented. 相似文献
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Z. Fattah G. Loget V. Lapeyre P. Garrigue C. Warakulwit J. Limtrakul L. Bouffier A. Kuhn 《Electrochimica acta》2011,(28):10562
Autonomous microswimmers are of enormous interest not only from an academic point of view, but also for future practical applications ranging from miniaturized motors to nanomedicine. A key step for the generation of such objects is their dissymmetric modification with a catalyst particle that activates the chemical conversion of a fuel molecule, leading ultimately to the propulsion of the object. So far it has been quite difficult to synthesize such dissymmetric objects and most approaches are based on using interfaces to break the symmetry. We demonstrate here that a very simple approach based on bipolar electrochemistry allows the bulk generation of carbon microtubes that are modified selectively at one end with a Pt cluster. The presence of this metal cluster allows the catalytic decomposition of hydrogen peroxide and the resulting oxygen bubbles trigger the propulsion of the object. The type of motion can be switched from linear to circular as a function of the exact position of the Pt cluster. 相似文献
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综述了煤炭电化学脱硫的原理 ,借助煤在电解槽阳极发生的电化学氧化反应将煤中的无机硫或有机硫氧化成可溶于水的硫化物 ,介绍了电解脱硫设备及工艺流程、电化学脱硫技术发展方向及趋势 ,认为该方法的显著特点是常温常压下操作 ,工艺简便 ,能量回收率高 ,并可联产大量高纯氢气 ;同时也指出了煤炭电化学脱硫技术中存在的问题 相似文献
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Direct electrochemistry of hemoglobin can be performed in acidic and basic aqueous solutions in the pH range 1-13, using stable, electrochemically active films deposited on a didodecyldimethylammonium bromide (DDAB) modified glassy carbon electrode. Films can also be produced on gold, platinum, and transparent semiconductor tin oxide electrodes. Hemoglobin/DDAB films exhibit one, two, and three redox couples when transferred to strong acidic, weak acidic and weak basic, and strong basic aqueous solutions, respectively. These redox couples, and their formal potentials, were found to be pH dependent. An electrochemical quartz crystal microbalance and cyclic voltammetry were used to study the in situ deposition of DDAB on gold disc electrodes and hemoglobin deposition on DDAB film modified electrodes. A hemoglobin/DDAB/GC modified electrode is electrocatalytically reduction active for oxygen and H2O2, and electrocatalytically oxidation active for S2O42− through the Fe(III)/Fe(II) redox couple. In the electrocatalytic reduction of S4O62−, S2O42−, and SO32−, and the dithio compounds of 2,2′-dithiosalicylic acid and 1,2-dithiolane-3-pentanoic acid, the electrocatalytic current develops from the cathodic peak of the redox couple at a potential of about −0.9 V (from the Fe(II)/Fe(I) redox couple) in neutral and weakly basic aqueous solutions. Hemoglobin/DDAB/GC modified electrodes are electrocatalytically reduction active for trichloroacetic acid in strong acidic buffered aqueous solutions through the Fe(III)/Fe(II) redox couple. However, the electrocatalytic current developed from the cathodic peak of the redox couple at a potential of about −0.9 V (from the Fe(II)/Fe(I) redox couple) in weak acidic and basic aqueous solutions. The electrocatalytic properties were investigated using the rotating ring-disk electrode method. 相似文献
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Copolymer of aniline and pyrrole was synthesized by inverted emulsion polymerization method by oxidizing aniline and pyrrole using benzoyl peroxide in presence of sodium laurylsulphate surfactant and p‐toluenesulphonic acid. Copolymer samples were characterized by infrared, X‐ray diffraction and scanning electron microscopic techniques and compared their properties with the corresponding homopolymers. The optimum reaction conditions for the preparation of copolymer with reasonably good yield (1.72 g) and conductivity (7.3 × 10?2 S/cm) were established. The synthesis procedure was extended to prepare copolymer samples using various protonic acids. Electrochemical characterization such as cyclic voltammetry, charge‐discharge and impedance were carried out on symmetrical supercapacitor cell consists of poly(aniline‐co‐pyrrole)‐p‐toluenesulfonic acid salt, wherein, the copolymer salt was synthesized using equal amount of aniline and pyrrole monomers. The values of specific capacitance, energy and power densities for poly(aniline‐co‐pyrrole)‐p‐toluenesulfonic acid system (PANI‐PPy) were calculated from charge‐discharge studies and are found to be 21 F/g, 5.7 Wh/Kg and 100 W/Kg respectively. Impedance analysis showed specific capacitance value (57 F/g) at 0.01 Hz at 0.22 V. Among the copolymer salts, copolymer prepared with sulfuric acid showed higher capacitance (66 F/g). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献