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莰烯在对－甲苯磺酸等催化下与炔丙醇、２－炔丁醇、３－三甲基硅基炔丙醇反应，分别制制得冰片基炔丙基醚，冰片基－２－炔丁基醚和冰片基－（３－三甲基硅基）炔丙基醚，产率６３％－７４％。 相似文献
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莰烯在硫酸催化下与１，４－丁炔二醇，乙二醇，１，２－丙二醇，１，３－丙二醇反应，分别制得４－冰片氧基－２－丁炔－１－醇，２－冰片氧基乙醇，１－冰片氧基－２－丙醇，３－冰片氧基－１－丙醇，产率分别为５２．７％，５９．７％，４２．６％和４２．０％。上述产物用乙酸酐酯化后得到相应的乙酸酯，其产率分别为８１．３％，７８．９％，７４．８％和７３．６％。所制备的化合物均进行了ＭＳ、ＩＲ、＾１Ｈ ＮＭＲ分析和评 相似文献
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将莰烯分别与１，２－丙二醇及１，３－丁二醇加成所得产物１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］２－丙醇及４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁醇，氧化得到两只新型的可用作香料的萜醚酮，１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］丙酮，与４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁酮。 相似文献
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将莰烯分别与１，２－丙二醇及１，３－丁二醇加成所得产物１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］２－丙醇及４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁醇，氧化得到两只新型的可用作香料的萜醚酮，１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］丙酮，与４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁酮。 相似文献
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２．５陶瓷 陶瓷刀具材料分为三大类： （１）氧化铝基陶瓷：一般在Ａｌ２Ｏ３基中加入ＴｉＣ、ＷＣ、ＳｉＣ、ＴａＣ、ＺｒＣ等成分，经热压制成复合陶瓷，硬度达ＨＲＣ９３～９５，抗弯强度０．７～０．９ＧＰａ。为提高韧性，常加少量Ｃｏ、Ｎｉ等。 （２）氮化硅基陶瓷：常用的是 Ｓｉ３Ｎ４＋ ＴｉＣ＋Ｃｏ复合陶瓷，其韧性高于氧化铝基陶瓷，硬度相当。 （３）复合氮化硅—氧化铝陶瓷：其组成为Ｓｉ３Ｎ４占 ７７％，Ａｌ２Ｏ３占 １３％，Ｙ２Ｏ３占 １０％。硬度可达 ＨＶ１８００，抗弯强度１．２ＧＰａ。该陶瓷又称赛阿隆（ Ｓｉ… 相似文献
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冰片基羟烷基醚的合成与酯化 总被引：1，自引：0，他引：1
莰烯在硫酸催化下与1,4-丁炔二醇,乙二醇,1,2-丙二醇,1,3-丙二醇反应,分别制得4-冰片氧基-2-丁炔-1-醇,2-冰片氧基乙醇,1-冰片氧基-2-丙醇,3-冰片氧基-1-丙醇,产率分别为52.7％,59.7％,42.6％和42.0％。上述产物用乙酸酐酯化后得到相应的乙酸酯,其产率分别为81.3％,78.9％,74.8％和73.6％。所制备的化合物均进行了MS、IR、~1H NMR分析和评香鉴定。 相似文献
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研究了兰考泡桐（Ｐａｕｌｏｗｎｉａｅｌｏｎｇａｔａ）木片用４种酶液（纤维素酶液ＥＳ２８、半纤维素酶ＥＡｎ７６、木质素酶Ｅ０２５及Ｅ０１４）预处理制生物机械浆。测定了预处理对木片主要化学组成、磨浆能耗、纸浆强度的影响。结果表明：（１）Ｅ０１４、Ｅ０２５、ＥＳ２８、ＥＡｎ７６预处理后，木片失重３．１８％～３．７２％，其中３．９％～１８．６％为木质素损失，纤维素损失则高达３８．２％～４６．２％；（２）磨浆度为５５ＳＲ时，４种酶液可节省能耗２．０％～７．０％，裂断长变化为－１８．１％～７．９％，耐破度变化为－１３％～７．３％，撕裂度为－１２．９％～８．４％，光学性质（如白度、光散射系数）变化不大，不透明度几乎不变。综合能耗节省与强度性质的提高，Ｅ０１４及ＥＡｎ７６效果较好，ＥＳ２８则由于纤维素酶对纤维的损伤效果不佳，Ｅ０２５效果则一般。 相似文献
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３，７－二甲基－１，６－辛二烯（１）在固体酸（分子筛，离子膜和离子交换树脂）作用下与甲酸发生环化水合反应，生成１－（３，３－二甲基环己基）乙醇甲酸酯（４ａ）和３，７，７－三甲基环庚醇甲酸酯（５ａ）的混合物，经皂化反应得到相应的醇（４ｂ和５ｂ）。５，７－二甲基－１，６－辛二烯（２）在同样条件下发生类似的反应，生成３，３，５－三甲基环庚醇甲酸酯（６ａ）经皂化生成３，３，５－三甲基环庚醇（６ｂ）。 相似文献
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-蒎烯合成龙脑研究 总被引：2，自引：1，他引：1
在固体超强酸催化作用下β-蒎烯和无水草酸平稳地发生酯化反应,生成草酸龙脑酯;加入氢氧化钠溶液发生皂化反应得到龙脑。酯化反应采用程序升温的方式（65℃、1h,75℃、4h,90℃、1h）,皂化反应时间为1h。在上述反应条件下,当催化剂SO4^2-／ZrO2用量为7％时（以β-蒎烯质量计,下同）,粗龙脑产率为62．0％,产品中正、异龙脑比为13．6：48．7;当催化剂S2O8^2-／ZrO2用量为7％时,粗龙脑产率为66．7％,正、异龙脑比为11．5：49．5;这两种催化剂对正龙脑选择性比较差。当用稀土复合固体超强酸SO4^2-／ZrO2-CeO2为催化剂,用量3％时,粗龙脑产率为56．1％,但对正龙脑的选择性高于其他催化剂,正、异龙脑比为46．0：23．2。 相似文献
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银杏叶用园建园材料选择的研究 总被引：2，自引：0，他引：2
对来自浙江、河南、山东、江苏等银杏产地的１３个优良单株３年生银杏嫁接苗的叶产量、黄酮含量、黄酮的组成成份、内酯含量、内酯的组成成份及黄酮、内酯的年变化规律等进行了比较研究。结果表明,不同银杏优良单株间的叶产量、黄酮含量、内酸含量等存在显著差异;黄酮和内酯在叶中的含量以９￣１０月最高,银杏植株各器官中黄酮的含量以叶最高,茎最低;在总黄酮中,槲皮素所占比例最大,其次为山奈酚,最后为异鼠李素;内酯的组成成分中则以银杏内酯Ａ为最大,其次为白果内酯,最后为银杏内酯Ｂ、银枵内酯Ｃ;根据叶产量、黄酮产量、内酯产量等指标,将１３个银杏叶用优良单株分成３类：优－Ｅ４,中等－Ｅ１、Ｅ２、Ｅ５、Ｅ６,差－Ｅ３、Ｅ７、Ｅ８、Ｅ１０、Ｗ２、Ｗ３、Ｗ４、Ｗ５,即优良单株Ｅ４是采叶园最后的建园材料,Ｅ１、Ｅ２、Ｅ５、Ｅ６等次之。 相似文献
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Constituents and cytotoxicity of Zanthoxylum rhesta stem bark 总被引：2，自引：0，他引：2
3,5-Dimethoxy-4-geranyloxycinnamyl alcohol (1), 8-methoxy-N-methylflindersine (2), xanthyletin and sesamin have been isolated from petroleum ether extract of the stem bark of Zanthoxylum rhesta. The petroleum ether extract and 8-methoxy-N-methylflindersine showed cytotoxicity on brine shrimp nauplii. 相似文献
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The extract from leaves of Rhododendron dauricum L. was extracted with 95% alcohol by common method for studying its insecticidal activities. The chemical components of the alcohol extract and relative contents were analyzed by GC-MS. The insecticidal activities of the alcohol extract were tested on the 2nd?3rd instar larvae of Lymantria dispar L. for five days. Five concentrations of the extract samples were designed as 50, 10, 5, 1, and 0.5 g?L?1. The results show that the alcohol extracts from leaves of R. dauricum exhibited insecticidal activities against larvae of L. dispar. The corrected mortality of larvae of L. dispar for was over 50% for both contact toxicity and stomach toxicity at the extract concentration of ≥ 5 g·L?1 after five days of application. The insecticidal activity in contact toxicity is more effect than stomach toxicity for the alcohol extract. Twenty compounds, with total GC relative contents of 93.81% in the alcohol extract from leaves of R. dauricum were identified. The main chemical components in the extract are: (1) 4,5-Dihydro-5-oxo-3-(p-tolyl) isoxazole, with a relative content of 40.03%; (2) 1,3-Benzenediol, 5-methyl-2-(3,7,11-trimethyl-2,6,10- dodecatrienyl)-, (E,E)-, the relative content 18.27%; (3) 3,6-Diphenyl- 1,2,3,4,5,6,7,8-octahydro-1,8-acridinedione, the relative content 3.89%; (4) 6H-[1,2,4]Triazolo[1,5-a]indole, 4a,5,7,8,8a,9-hexahydro-9- methylene-, the relative content 2.99%; (5) 7-Amino-4-methyl-1,8- naphthyridin-2-ol, the relative content 2.64%; (6) 4-Methyl-2,6- dihydroxyquinoline, the relative content 2.63%; (7) 2,4,6- Triaminoquinazoline, the relative content 2.27%; (8) 2(1H)-Quinolinone, 4-hydroxy-1-methyl-, the relative content 2.02%. 相似文献
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To characterize the mechanism of the reaction of lignin with aqueous acetic acid (AW) containing a small amount of H2SO4, guaiacylglycerol--guaiacyl ether (GOG), and guaiacylglycerol--syringol ether (GOS) were refluxed in 90% AW with 0.28% H2SO4 for 0–120 min. Reaction products and their silylated derivatives were characterized by analytical methods such as gas chromatography-mass spectrometry and nuclear magnetic resonance. When the model compounds were allowed to react at boiling temperature for 0 min (heat-up time 30 min), most of their primary alcohol groups and some of their secondary alcohol groups were acetylated, but their phenolic groups were not. About 90% of GOG was degraded, polymerized, or both during boiling for at least 15 min, yielding guaiacol and isocoumaran compounds (GOG-e and GOG-f) in addition to homovanillin (II) as guaiacylvinyl alcohol (I) and other minor products. GOS yielded syringol, homovanillin (II), and a novel compound (V) together with unknown products but not the corresponding isocoumaran compounds. 相似文献
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以柚皮苷和橙皮苷为原料,经碘/吡啶脱氢,O-甲基化和糖苷水解等反应,分别合成了2种天然黄酮芹菜素-5,4'-二甲醚(1)和木犀草素-5,3',4'-三甲醚(2)。然后以1和2为底物,分别与甲醛、二级胺在酸性醇溶剂中发生微波协助的Mannich反应,对黄酮8-位进行胺甲基化修饰,合成了15个新型黄酮Mannich碱衍生物3~17。所合成的化合物经~1H NMR、~(13) C NMR和MS等进行了结构确证,并采用细胞计数Kit-8(CCK-8)法测试了化合物1~17对子宫颈癌Hela细胞的体外抑制活性。结果表明,化合物1、2、7、9、10、12和17对Hela细胞增殖具有明显的抑制活性,其中化合物10、12和17的半数抑制浓度(IC_(50))分别为16.13、29.04和9.14μmol/L,活性高于阳性对照药物顺铂(IC_(50)为41.25μmol/L)。 相似文献
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以核桃壳和杏壳为原料,采用磷酸法制备活性炭,以亚甲基蓝吸附值、碘吸附值和得率为指标,研究了原料粒径和含水率对磷酸法活性炭性能的影响。结果表明:原料的粒径和含水率对活性炭的吸附性能有重要影响,在一定范围内减小原料粒径,对提高活性炭吸附性能有利,而原料含水率对活性炭吸附性能的影响因不同原料而异。增加原料含水率,对核桃壳活性炭吸附性能的提高有利,但会降低小粒径杏壳活性炭的吸附性能。以核桃壳为原料制备活性炭时,选择粒径0.5~0.7 mm、含水率11%的原料为佳,得率可达41%,亚甲基蓝吸附值230 mg/g,碘吸附值874 mg/g;以杏壳为原料制备活性炭时,选择粒径0.7~1.2 mm、烘干的原料为佳,得率可达42%,亚甲基蓝吸附值87 mg/g,碘吸附值734 mg/g。 相似文献
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Takuya Akiyama Tomoko Sugimoto Yuji Matsumoto Gyosuke Meshitsuka 《Journal of Wood Science》2002,48(3):210-215
Ozonation as a quantitative tool to analyze the stereo structures of arylglycerol--aryl ether linkages was examined using wood meal, milled wood lignin, and a lignin model compound, 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol (veratrylglycerol--guaiacyl ether, VG). The procedure was improved. When mild postreduction was conducted for ozonation products, the total yield of erythronic and threonic acids from this model compound was 74%, which is 15% higher than the yield without postreduction. A decrease in the recovery of these two acids under prolonged ozonation treatment was successfully suppressed by postreduction. Theerythro/threo ratio of VG determined by the ozonation method with postreduction is in good agreement with the ratio determined by1H-nuclear magnetic resonance. Excellent reproducibility of the yield was obtained by adopting a procedure that included trimethylsilylation of ammonium salts of ozonation products using a dimethylsulfoxide-hexamethyldisilazane-trimethylchlorosilane mixture and subjecting it to gas chromatography analysis. It was concluded that arylglycerol--aryl ether structures comprise at least 35% of the C3-C6 structure in birch wood meal, with anerythro/threo ratio of 2.8.This paper was presented at the 43rd Lignin Symposium, Fuchu, Japan, October 1998; and at the 10th ISWPC, Yokohama, Japan, June 1999 相似文献