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Production and Utilization of L-Arabinose in China
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作者 Biao Hu Haiyang li +5 位作者 Qingfu Wang Yicong Tan Ruirong Chen jingrong li Wenting Ban Lei liang 《World Journal of Engineering and Technology》 2018年第3期24-36,共13页
L-arabinose is a newly developed low-caloric monosaccharide, which has many biomedical and health effects, especially intestinal sucrase inhibition effect. L-arabinose is mainly produced by chemical or enzymatic hydro... L-arabinose is a newly developed low-caloric monosaccharide, which has many biomedical and health effects, especially intestinal sucrase inhibition effect. L-arabinose is mainly produced by chemical or enzymatic hydrolysis of hemicellulose. The taste of L-arabinose is quite similar to that of sucrose, with approximately 50% of the sweetness. As a functional additive, L-arabinose can be used in medical and pharmaceutical applications for the treatment of diseases such as diabetes, chronic constipation, mineral absorption disorder and secondary bile acid formation disorder. However, L-arabinose has not been widely used in functional foods due to high price and lack of publicity and guidance. A comprehensive review of L-arabinose physicochemical properties, production, applications field, market statue and development direction is presented in this paper. 展开更多
关键词 L-ARABINOSE Application FIELDS MARKET STATUE Development Direction
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MnCo改性的MCM-41催化剂用于氯苯催化燃烧的研究(英文) 被引量:6
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作者 成珍 李敬荣 +1 位作者 杨鹏 左树锋 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期849-856,共8页
含氯挥发性有机化合物(CVOCs)是对人体健康和环境危害极大的有机化合物.常见的有二氯乙烷、三氯乙烯、三氯甲烷、四氯化碳和氯苯等.有些CVOCs是"三致"(致畸、致癌、致突变)物质,有些少量进入大气就能破坏臭氧层,亦或与臭氧等... 含氯挥发性有机化合物(CVOCs)是对人体健康和环境危害极大的有机化合物.常见的有二氯乙烷、三氯乙烯、三氯甲烷、四氯化碳和氯苯等.有些CVOCs是"三致"(致畸、致癌、致突变)物质,有些少量进入大气就能破坏臭氧层,亦或与臭氧等形成光化学烟雾,引起全球变暖.因此,对于其消除迫在眉睫.CVOCs通常采用高温直接燃烧、吸附、光催化氧化和催化燃烧等方法降解.其中,催化燃烧是非常有效的.我们选择氯苯作为CVOCs探针分子是因其不仅存在于农药和化工产品中,在室内环境中也大量存在,而负载贵金属和非贵金属型催化剂可用于其催化降解.贵金属催化剂价格高而且易氯中毒,但过渡金属催化剂价格低且抗失活,因而是不错的选择.通常过渡金属催化剂使用V_2O_5,Cr_2O_3,MnO_2,Co_3O_4及NiO等活性组分,而Mn和Co氧化物有较好活性且没有环境污染,常用作活性组分.另外,MCM-41是有序介孔硅酸盐和硅铝酸盐家族中M41S的一员,具有高的比表面积和较窄的孔径分布,常用作催化剂的载体.我们利用具有大比表面积、大孔径的MCM-41作为载体,采用浸渍法负载MnO_x,CoO_x,MnO_x-CoO_x等活性组分,制备系列的催化剂用于低浓度氯苯的催化燃烧,研究催化剂的催化活性、选择性及稳定性.并利用XRD、N_2吸脱附、高分辨电镜-能谱分析、H_2-TPR和CB-TPD等手段对MCM-41及催化剂的织构-结构、表面形貌、活性组分分散状态、氧化还原性能及吸附性能等做了系统的研究.采用表面活性剂软模板技术合成了具有大比表面积、大孔径、耐热稳定性高的MCM-41介孔分子筛,负载不同比例的Mn/Co(摩尔比是3:1、6:1及9:1,其中总负载量为10%),以氯苯催化燃烧为探针反应,筛选出活性最佳时的Mn/Co比例.活性评价实验结果表明,各催化剂的活性以下列顺序依次降低:MnCo(6:1)/MCM-41>MnCo(9:1)/MCM-41>MnCo(3:1)/MCM-41>Mn/MCM-41>Co/MCM-41,其中MnCo(6:1)/MCM-41活性最佳,在270 oC即可完全催化燃烧氯苯.耐久性实验结果显示,MnCo(6:1)/MCM-41在连续反应1000 h后,其活性没有降低,表明其具有非常良好的稳定性.XRD实验结果表明,在Mn/MCM-41及Co/MCM-41催化剂上分别检测到MnO_2及Co_3O_4的特征衍射峰.在MnCo(6:1)/MCM-41催化剂上,MnO_2及Co_3O_4的特征衍射峰消失,同时出现了MnCoOx的特征衍射峰,这是由于MnO_2及Co_3O_4的强相互作用经过焙烧后形成的,且MnCoO_x的特征衍射峰较小,表明双金属活性组分的分散比单金属催化剂好.N_2吸脱附结果显示,MCM-41的比表面积达到805.9 m^2/g,孔体积达到0.795 cm^3/g.负载活性组分后其比表面积及孔体积均有不同程度的减小,这是由于活性组分进入了MCM-41的孔隙.高分辨电镜结果表明,MCM-41具有均匀的介孔孔道结构,MnCoO_x在MCM-41表面的颗粒小,分散好.能谱扫描出Mn,Co,O等元素,表明活性组分成功地负载在MCM-41载体上.H_2-TPR表明,双金属催化剂的还原峰温较单金属催化剂低,表明其具有更好的氧化性能.CB-TPD结果表明,MnCo双金属催化剂脱附氯苯的温度高于单金属催化剂,说明氯苯与催化剂之间的相互作用更强,即双金属催化剂对氯苯的吸附能力更强,使得氯苯催化燃烧更加充分,因此其催化性能更好.同时,深入探讨了MnO_x,CoO_x,MnCoO_x和MCM-41之间的相互作用及对催化燃烧性能的影响. 展开更多
关键词 MCM-41分子筛 Mn/Co 催化燃烧 氯苯 表征
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Atramacronoids A-C,three eudesmanolide sesquiterpene-phenol hybrids with an unprecedented C-C linkage from the rhizomes of Atractylodes macrocephala
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作者 Haixin Zhang jingrong li +8 位作者 Jinguang Si Chengya Dong Qi li Meng Yu lingling Qin lingyu li Chenxu Zhao Tao Zhang Zhongmei Zou 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第1期284-288,共5页
Three eudesmanolide sesquiterpene-phenol hybrids,atramacronoids A-C(1-3),featuring an unusual6/6/5/5/6 skeleton furnished by forming an unexpected C-8-C-16 linkage,were obtained from the rhizomes of Atractylodes macro... Three eudesmanolide sesquiterpene-phenol hybrids,atramacronoids A-C(1-3),featuring an unusual6/6/5/5/6 skeleton furnished by forming an unexpected C-8-C-16 linkage,were obtained from the rhizomes of Atractylodes macrocephala.Their structures and absolute configurations were elucidated by spectroscopic data analysis,chemical calculations,combined with X-ray diffractions.The plausible biosynthetic pathways for compounds 1-3 are proposed.Surprisingly,compound 1 exhibited cytotoxicity against SGC-7901 cells by inducing cells apoptosis,which might relate to the promotion of synthesis of neutrophil elastase. 展开更多
关键词 Atractylodes macrocephala COMPOSITAE Sesquiterpene-phenol hybrids ANTI-CANCER Neutrophil elastase
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