青蒿素及其衍生物对菜青虫的生物活性

以二氢青蒿素为原料合成了10种双二氧青蒿素醚和5种单二氢青蒿素醚,用常规的非选择性叶碟法测定了质量浓度为1.0 g/L的合成化合物、青蒿素和二氢青蒿素对菜青虫的生物活性.结果表明:双醚对菜青虫的拒食活性最为显著,处理后24、48 h的拒食率分别为85.4%～96.9%和90.9%～98.6%,单醚分别为45.5%～60.6%和50.9%～68.2%,二氢青蒿素为36.6%和42.4%,青蒿素为40.1%和47.0%;双醚同样具有较高的杀虫活性,其处理后96 h的校正死亡率为72.7%～95.5%,单醚为45.4%～54.6%,二氢青蒿素为49.9%,青蒿素的杀虫活性不显著.结合活性数据,初步讨论了青蒿素衍生物的构效关系.     

四氢咔唑酮离解常数的光度法测定

研究了四氢咔唑酮在不同比例的乙醇.水混合溶剂中及不同酸度下的吸收光谱,提出了采用紫外分光光度法测定四氢咔唑酮在水中离解常数的方法.试验证明:在不同比例的乙醇.水混合溶剂中,四氢咔唑酮的离解常数与乙醇的体积分数存在良好的线性关系,通过外推至乙醇含量为零,可求得在实验条件下四氢咔唑酮在水溶液中的离解常数pKb为14.04.     

季戊四醇双缩二苄基甲酮的无溶剂合成研究

在无溶剂条件下,以SO4～2-/TiO₂-SnO₂固体超强酸为催化剂,合成了季戊四醇双缩二苄基甲酮;考察了催化剂的用量、反应物的摩尔比、反应时间和反应温度等对缩酮反应的影响。结果表明,催化剂的用量为反应物总质量的0.9%,季戊四醇和二苄基甲酮的摩尔比为1:2.3,反应温度为160℃,反应时间为8 h时,季戊四醇双缩二苄基甲酮的产率达74,5%。     

新型抗氧剂KY-1330合成的研究

采用两步法合成抗氧剂1,3,5-三甲基-2,4,6-三(3,5-二叔丁基-4-羟基苄基)苯(KY-1330),先以2,6-二叔丁基苯酚和多聚甲醛为原料,醚化合成3,5-二叔丁基-4-羟基苄基甲基醚,再与均三甲苯进行缩合反应得到抗氧剂KY-1330。通过正交实验优化了反应条件,醚化条件为:2,6-二叔丁基苯酚15.0 g,多聚甲醛3.5 g,催化剂二甲胺用量1.5 mL,反应温度100℃,反应时间为190 min,搅拌速度100 r/min,产率为87.2%;缩合条件为:3,5-二叔丁基-4-羟基苄基甲基醚与均三甲苯的摩尔比为4∶1,反应温度为5℃,反应时间为120 min,硫酸质量分数为80%,产率为81.5%。     

二氢杨梅素的制备及其对酪氨酸酶的抑制研究

通过正交实验确定超声波提取藤茶中总黄酮的最佳工艺条件,用柱层析-重结晶法从藤茶中分离得到二氢杨梅素。选用L-酪氨酸、L-多巴为底物,分别测定二氢杨梅素对酪氨酸酶的单酚酶、二酚酶的抑制率。结果表明,提取的最佳工艺条件:提取溶剂是体积分数为60%的乙醇,料液比1∶30(g/mL),提取温度40℃,提取时间40 min,总黄酮得率为46.54%。柱层析-重结晶法分离纯化得到的二氢杨梅素得率为41.12%,纯度为99.12%。二氢杨梅素对单酚酶、二酚酶均有显著的抑制作用,抑制率分别可达95.87%,69.01%。     

HNPC-A9908正辛醇/水分配系数的测定

采用摇瓶法,对HNPC-A9908[O-(3-苯氧苄基)-2-甲硫基-1-(4-氯苯基)丙基酮肟醚]这一新的非酯肟醚类拟除虫菊酯杀虫剂在醇/水体系中的分配系数的测定。测定结果表明,在25℃条件下,振荡5￣7h可达到平衡,分配系数平均为5.00。     

（3aS,6aR）-1,3-二苄基-四氢-4H-噻吩并[3,4-d]咪唑-2,4-二酮（1H）制备工艺优化

d-生物素的重要中间体：（3aS,6aR）-1,3-二苄基-四氢-4H-噻吩并[3,4-d]咪唑-2,4-二酮（1H）（以下简称硫代内酯）由（3aS,6aR）-1,3-二苄基-四氢-4H-呋喃并[3,4-d]咪唑-2,4-二酮（1H）（以下简称内酯）中呋喃环上的氧用硫取代而成。目前常用的硫代工艺均有一些明显的弊端,本文对硫代工艺进行改进,可以提高硫代反应的收率和产物的质量。     

含Pd类水滑石催化剂的活性研究

用共沉淀法制备Pd类水滑石催化剂,用固定床管式反应装置测试催化剂对丙酮一步法制备MIBK的催化活性,研究了反应温度、氢酮比、进料液空速及催化剂组成对该反应的影响.在常压下,反应温度为180℃,氢酮摩尔比为1.5,液空速为1.20 h-1,选取不同组成的催化剂进行催化性能测试.结果表明:当Mg/Al比为3:1,Pd质量分数是0.2%时,丙酮的转化率达到82.87%,MIBK的选择性为53.56%,收率为44.39%.     

抗氧剂330合成工艺研究

研究了以中间体3,5-二叔丁基-4-羟基苄基甲基醚（简称苄醚）与均三甲苯为原料，在硫酸催化剂的作用下合成1,3,5-三甲基-2,4,6-三（3,5-二叔丁基-4-羟基苄基）苯（简称抗氧剂330）的工艺条件，确定了主要杂质的种类和结构，提出了副反应的反应机理，确定了副反应抑制剂的类型和用量。结果表明，合适的反应条件：硫酸含量为94.0%(w)，催化剂与苄醚摩尔比1.2∶1.0，促进剂乙酸用量为苄醚质量的20%，反应温度宜控制在-10℃，苄醚与均三甲苯摩尔比（3.2∶1.0）～(3.3∶1.0)；确定了影响抗氧剂330透光率和收率的2种主要杂质及其结构，分别为4,4′-双-（2,6-二叔丁基苯酚）甲烷和1,3,5-三甲基-2,4-二（3,5-二叔丁基-4-羟基苄基）苯；在反应体系中添加甲缩醛，可以抑制副反应的发生，合适的用量为苄醚质量的2.5%～5.0%；在优化的工艺条件下合成抗氧剂330，平均收率为87.7%,425,500 nm透光率均超过95%，达到了优级品的要求。     

天然抗氧化剂二氢杨梅素的热稳定性及抗氧化性质研究

研究了新型食品用天然抗氧化剂二氢杨梅素的热稳定性及增效剂对其在植物油体系的抗氧化活性的影响.采用差示扫描热分析法研究了二氢杨梅素的热稳定性,结果表明二氢杨梅素可在220℃以下的高温使用.并确定纯度为95%的二氢杨梅素在花生油体系中的最优添加量为0.04%,并且当增效剂L-抗坏血酸和亚硫酸钠的添加量为0.02%时,可有效地提高二氢杨梅素的抗氧化性能.     

Pyrolysis of hydrocarbon mixtures characteristic of coal: Application to dibenzyl mixture

Thermal cracking of dibenzyl dissolved in two solvents, tetralin and decalin, has been studied in a flow reactor, in the presence of steam, under atmospheric pressure and at temperatures between 600 and 750 °C. The nature of the products obtained depends upon the structure of the hydrogen-donor agent, but is independent of the structure of dibenzyl. Valuable products such as ethylene and a benzene, toluene and xylene (BTX) mixture, obtained by a β-scission reaction with a monomolecular mechanism, are predominant when decalin is used as solvent. The dehydrogenation of tetralin to naphthalene precedes cracking reactions of the bimolecular type, which lead to significant production of hydroaromatics such as indene. Cracking of dibenzyl, followed by hydrogen transfer from the solvent to the radicals formed, leads to toluene irrespective of the chemical nature of the hydrogen donor.     

Free radical chemistry of coal liquefaction: role of molecular hydrogen

Model compounds containing the types of carboncarbon bonds thought to be present in coal were pyrolyzed in the presence of tetralin and molecular hydrogen at 450 °C. The relative rates of conversion of the model structures are predictable from the bond dissociation energies of the compounds. Conversion of dibenzyl in the presence of both tetralin and molecular hydrogen or in the presence of hydrogen alone proceeds along two parallel reaction paths. Toluene is produced by a thermal cracking reaction in which the rate-controlling step is the thermal cleavage of the β-bond in dibenzyl. Benzene and ethylbenzene are produced by a hydrocracking reaction. The rate of the hydrocracking reaction is directly proportional to the hydrogen pressure. The strong bond in diphenyl is hydrocracked in a system containing both molecular hydrogen and a source of free radicals. These studies on model coal structures offer firm evidence that molecular hydrogen can participate directly in free radical reactions under coal liquefaction conditions. Under some conditions molecular hydrogen can compete with a good donor solvent to stabilize the thermally produced free radicals. Molecular hydrogen can also promote some hydrocracking reactions in coal liquefaction that do not occur to an appreciable extent in the presence of only donor.     

磷改性USY分子筛催化剂上四氢萘选择性开环反应性能

通过P改性对USY分子筛酸量进行调节,考察酸量对四氢萘选择性开环反应的影响。结果表明,P改性后USY分子筛弱酸量增加,中强酸略增,强酸基本不变,P_(0.5)-USY分子筛弱酸量增加有利于四氢萘生成不饱和开环产物。负载贵金属Pt后,Pt_(0.4)/P_(0.5)-USY催化剂上四氢萘转化率99.37%,开环选择性40.79%,贵金属Pt的引入对结焦前驱体的生成有抑制作用。     

Highly efficient and organic nitrogen‐containing cation‐promoted aerobic oxidation of alkylaromatics in the presence of N‐hydroxyphthalimide

BACKGROUD: Direct oxidation of alkylaromatics to the corresponding aromatic ketone is an important process in the manufacture of perfumes, pharmaceuticals, flavors, dyes and agrochemicals. For example, tetralin is oxidized to produce 1‐tetralinone, which is a key intermediate in the commercial production of 1‐naphthol, 2‐hydroxy‐1‐tetralone, aureolic acid antibiotics and other pharmaceuticals. RESULTS: In this investigation, it was found that alkylaromatics could be efficiently and selectively oxidized to the corresponding aromatic ketones when methyl violet was employed as a promotor in the presence of N‐hydroxyphthalimide (NHPI); tetralin was oxidized with 89% conversion and 76% selectivity to 1‐tetralinone under 0.3 MPa of O₂ at 75 °C for 2.5 h. The effects of temperature, oxygen pressure, reaction time and additive inclusion were studied in detail. A possible reaction mechanism for tetralin oxidation has been proposed. CONCLUSION: It was demonstrated that methyl violet could efficiently promote the aerobic oxidation of alkylaromatics in the presence of NHPI under mild conditions. Further investigations indicated that the nitrogen cation had a crucial promotion effect in the oxidation process. Copyright © 2009 Society of Chemical Industry     

Hydrogenation of tetralin on a sulfided ruthenium on KY zeolite catalyst. Effect of the sulfidation method

Hydrogenation of tetralin was used to modelize the hydrogenation of aromatic compounds in gasoils. This reaction was carried out under a 5 MPa hydrogen pressure, at 300°C, in the presence of hydrogen sulfide. Before reaction, the Ru on KY zeolite catalyst was presulfided in situ at 400°C either by a H₂S/H₂ mixture, or by dimethyl disulfide in n-heptane. The catalyst sulfided by dimethyl disulfide was 3 times less active than that sulfided by H₂S, due to coking during sulfidation. Another type of carbonaceous deposit was formed during the tetralin reaction, the nature and the amount of this deposit was not depending on the sulfidation method.     

Evidence for the involvement of quinone rings in reactions of some coals with tetralin

Model compounds representing a variety of hydrocarbon groups and most of the oxygen-containing functional groups have been tested for reactivity with tetralin at 400° C. Only the quinones were capable of oxidizing tetralin to naphthalene. Anthraquinone is completely deoxygenated to anthracene. Evidence for homolysis of carbon-carbon bonds was found only in the case of dibenzyl, and this was not accompanied by oxidation of tetralin. The extractability of subbituminous coals with the non-reducing solvent, diphenyl-diphenyl ether eutectic, is correlated with oxygen content and depth of burial. It is suggested that oxidized coals near the surface contain quinone rings, and that dissolution by tetralin is primarily then due to lowering of the solvent parameter as a consequence of deoxygenation.     

煤基合成气甲烷化用镍基催化剂失活热力学和抗失活预测

利用热力学数据对煤基合成气甲烷化用镍基催化剂硫中毒以及积炭热力学进行了详细的计算。计算发现,活性金属Ni、Mo在甲烷化反应条件下与H₂S、COS发生反应是自发进行的过程。10^-10数量级分压的H₂S含量、10^-14数量级分压的COS含量即可使镍金属活性组分生成硫化镍而使催化剂失活;当Mo作为助剂添加到Ni基催化剂时,硫含量不能超过10^-6数量级。不同温度区间发生的积炭反应类型不同,当温度为633.15～898.15K时,积炭反应主要以CO歧化反应、CO还原反应为主;898.15～983.15K时以CH₄裂解反应为主。另外,在0.1MPa下,添加摩尔分数为11.11%及以上含量水蒸气可以避免积炭。     

配入低阶煤炼焦对焦炭性能影响的研究

选用焦煤、1/3焦煤、肥煤、瘦煤、长焰煤进行配煤,堆密度为0.7g/cm3和1.0g/cm3,采用2kg焦炉炼焦,对焦炭的冷态强度和热态性能分析检测,探讨了堆密度及低阶煤加入量对焦炭性能的影响,结果表明,配入低阶煤后,焦炭的冷态强度及热态性能变差,配比小于5%时,影响较小,适当提高原料煤堆密度,焦炭的冷态强度及热态性能得到改善。     

阳离子脱色剂的合成及应用

针对A/O生化处理后的焦化废水色度不达标问题,以双氰胺、甲醛为主要原料,合成了双氰胺-甲醛阳离子脱色絮凝剂,对焦化废水进行脱色试验。结果表明,当焦化废水色度为158、pH值为7、絮凝剂投加量为8mL/L时,脱色率可达61.21%。     

Aspects of the chemistry of donor solvent coal dissolution: Promotion of the bond cleavage reactions of diphenylalkanes and the related ethers and amines

The influences of Illinois No. 6 coal, benzyl phenyl sulphide, 9, 10-anthraquinone, tetracene, phenol and benzoic acid on the rates of decomposition of 1,2-diphenylethane, 1,3-diphenylpropane, 1, 4-diphenylbutane, benzyl phenyl ether, dibenzyl ether, N-benzylaniline, and dibenzylamine in tetralin have been investigated. Radical initiators such as benzyl phenyl sulphide enhance the rate of decomposition of the compounds that form benzylic radicals which can decompose via β-scission reactions. Weak organic acids enhance the reaction rates of the compounds, for example, benzyl phenyl ether and N-benzylaniline, that undergo the homolysis reaction via polar transition states. Among the reactive initiators considered in this Paper, benzyl phenyl sulphide is the only compound which, in small quantities, accelerates the conversion of Illinois No. 6 coal to pyridine-soluble products in tetralin at 400 °C. The facile reactions of Illinois No. 6 coal with tetralin and the accelerating effects of benzyl phenyl sulphide, anthraquinone, tetracene and phenols on the decomposition of the diphenylalkanes and the related heteroatom analogues are discussed.