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The Oxyalkylation of Hydrophilic Black Alder Bark Extractives with Propylene Carbonate with a Focus on Green Polyols Synthesis
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作者 Alexandr Arshanitsa Matiss Pals +1 位作者 Daniela Godina Oskars Bikovens 《Journal of Renewable Materials》 EI CAS 2024年第11期1927-1948,共22页
The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and l... The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and lowtoxic base-catalyzed modification with propylene carbonate(PC).FTIR spectroscopy,HP-LC,GC,GPC,and wet chemistry methods were used to characterize the starting constituents,intermediate and final products of the reaction and to monitor the different pathways of PC conversion.The reaction of extractives as well as the model compounds,including catechol,xylose,PEG 400,and benzoic acid,with PC indicated the ability of OH groups of different origins present in the extractives to condense with equivalent amounts of PC.The polyols obtained consist of a copolymer fraction with one oxypropyl unit grafted per OH functionality of extractive components on average and oligo oxypropyl diols with a small number of carbonate linkages in the chain,obtained as a result of remaining PC homopolymerization.The domination of the oxypropylation mechanism vs.transcarbonation for PC ring opening was observed for both copolymerization and homopolymerization processes,making the process of oxypropylation with PC similar to that of conventional oxypropylation.At optimal reaction conditions,including a PC/OH ratio of 3.0 and a 24-h duration at 150°C,uniform polyols with low viscosity of~900 mPa·s^(-1),a biomass content of~27%,and an OHV of~500 mg KOH·g^(-1) were obtained.Increasing the temperature of modification allows shortening the process but drastically increases the polyol viscosity.At fixed temperature values,increasing the PC/OH ratio not only decreases the biomass content but also strongly prolongs the processing.The significantly increased duration of the process using PC as an alternative oxyalkylation agent compared to that of oxyalkylation with propylene oxide is a reasonable trade-off for using a safer and more environmentally friendly technology. 展开更多
关键词 Bark extractives propylene carbonate OXYALKYLATION polyolS
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Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(NIPU) 被引量:1
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作者 Saeed Kazemi Najafi Farhood Najafi +2 位作者 Antonio Pizzi Fatemeh Hassani Khorshidi Rabi Behrooz 《Journal of Renewable Materials》 SCIE EI 2023年第5期2171-2190,共20页
Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and carbon-hydrogen.These compounds are mainly used as reactants to make other polymers.Amon... Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and carbon-hydrogen.These compounds are mainly used as reactants to make other polymers.Among biopolymers,lignin is regarded as the base of a new polymer in polyol construction.The present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the environment.To this aim,first,lignin was extracted from raw liquor.Next,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene carbonate.The results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified lignin.Moreover,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR analysis.Additionally,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample. 展开更多
关键词 polyol LIGNIN DIETHYLENETRIAMINE ETHYLENEDIAMINE propylene carbonate polyurethanes NIPU
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Preparation and Properties of Vegetable-Oil-Based Thioether Polyol and Ethyl Cellulose Supramolecular Composite Films
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作者 Ruyu Yan Jian Fang +7 位作者 Xiaohua Yang Na Yao Mei Li Yuan Nie Tianxiang Deng Haiyang Ding Lina Xu Shouhai Li 《Journal of Renewable Materials》 SCIE EI 2023年第4期1937-1950,共14页
Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes i... Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes it too brittle to be used widely.The hydroxyl group on EC can form a supramolecular system in the form of a non-covalent bond with an effective plasticizer.In this study,an important vegetable-oil-based derivative named dimer fatty acid was used to prepare a novel special plasticizer for EC.Dimer-fatty-acid-based thioether polyol(DATP)was synthesized and used to modify ethyl cellulose films.The supramolecular composite films of DATP and ethyl cellulose were designed using the newly-formed van der Waals force.The thermal stability,morphology,hydrophilicity,and mechanical properties of the composite films were all tested.Pure EC is fragile,and the addition of DATP makes the ethyl cellulose films more flexible.The elongation at the break of EC supramolecular films increased and the tensile strength decreased with the increasing DATP content.The elongation at the break of EC/DATP(60/40)and EC/DATP(50/50)was up to 40.3%and 43.4%,respectively.Noticeably,the thermal initial degradation temperature of the film with 10%DATP is higher than that of pure EC,which may be attributed to the formation of a better supramolecular system in this composite film.The application of bio-based material(EC)is environmentally friendly,and the novel DATP can be used as a special and effective plasticizer to prepare flexible EC films,making it more widely used in energy,chemical industry,materials,agriculture,medicine,and other fields. 展开更多
关键词 Ethyl cellulose dimeric fatty acid based thioether polyol supramolecular system composite films
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Polyol合成法制备生物医药用超小粒径Fe_3O_4磁性纳米晶体 被引量:6
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作者 刘红玲 吴君华 《化学研究》 CAS 2008年第3期9-13,共5页
采用一罐polyol合成法还原Fe(Ⅲ)乙酰丙酮化合物制备了粒径可调、单分散、直径5nm以下的磁性Fe3O4纳米晶体.其晶粒表面为所用聚合物表面活性剂PVP所包覆.运用透射电镜/高分辨透射电镜、X射线衍射、振动样品磁强计和超导量子干涉仪对其... 采用一罐polyol合成法还原Fe(Ⅲ)乙酰丙酮化合物制备了粒径可调、单分散、直径5nm以下的磁性Fe3O4纳米晶体.其晶粒表面为所用聚合物表面活性剂PVP所包覆.运用透射电镜/高分辨透射电镜、X射线衍射、振动样品磁强计和超导量子干涉仪对其结构和性能进行了表征.结果表明所制得的Fe3O4磁性纳米晶体在室温下显示出优良的超顺磁性,且结晶度高、分散性好、化学性质稳定同时表面易修饰.磁滞回线的模型分析说明该Fe3O4纳米晶粒是磁性单畴.该法制得的超顺磁Fe3O4纳米晶粒在生物和医学领域具有重要的应用价值. 展开更多
关键词 polyol合成法 超小粒径 FE3O4 尺寸控制
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微波辅助polyol法制备的纳米镍颗粒 被引量:4
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作者 徐小兵 刘先松 +2 位作者 Udi Meridor Aviad Frydman Aharon Gedanken 《磁性材料及器件》 CAS CSCD 2008年第6期33-35,共3页
采用微波辅助polyol还原法制备了单分散的纳米Ni颗粒。分别用X射线衍射(XRD)和透射电镜(TEM)观测样品的相结构和微观形貌,用振动样品磁强计(VSM)测试Ni颗粒的磁性。XRD显示样品为面心立方结构,TEM观察显示金属镍颗粒的形貌是理想的球型... 采用微波辅助polyol还原法制备了单分散的纳米Ni颗粒。分别用X射线衍射(XRD)和透射电镜(TEM)观测样品的相结构和微观形貌,用振动样品磁强计(VSM)测试Ni颗粒的磁性。XRD显示样品为面心立方结构,TEM观察显示金属镍颗粒的形貌是理想的球型。当把反应温度提高到400℃,并且在实验过程中加入适量的PVP时,发现镍颗粒呈现出一种毛茸茸的多毛形态,这种分散均匀的单一态形貌类似于纳米头发的结构。同时,VSM测试结果表明球型纳米Ni颗粒具有典型的铁磁性。 展开更多
关键词 单分散Ni球 微波辅助polyol还原法 结构 磁性
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微波辅助polyol法制备纳米金属镍及磁性研究 被引量:1
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作者 徐小兵 刘先松 +2 位作者 Udi Meridor Aviad Frydman Aharon Gedanken 《功能材料》 EI CAS CSCD 北大核心 2008年第4期553-556,共4页
采用微波辅助polyol法成功地制备了直径范围在5~10nm、100~180nm的单分散Ni球,对其磁性进行了测量分析。用XRD和EDAX,接着用TEM和MFM分别对制备的样品进行测试,并用VSM和SQUID进一步讨论了铁磁/反铁磁的界面耦合效应。XRD显示该... 采用微波辅助polyol法成功地制备了直径范围在5~10nm、100~180nm的单分散Ni球,对其磁性进行了测量分析。用XRD和EDAX,接着用TEM和MFM分别对制备的样品进行测试,并用VSM和SQUID进一步讨论了铁磁/反铁磁的界面耦合效应。XRD显示该样品是面心立方结构,EDAX数据表明制备过程中镍球被轻微氧化,MFM和TEM观察结果显示样品金属镍是比较理想的球型,VSM测试结果表明Ni纳米球具有典型的铁磁性。 展开更多
关键词 单分散Ni球 微波辅助polyol还原法 磁性
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镍纳米晶体的微波辅助polyol法可控合成与表征 被引量:1
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作者 章成文 刘先松 《兵器材料科学与工程》 CAS CSCD 2010年第4期56-58,共3页
通过微波辅助polyol法合成多种形态的镍纳米晶体,采用X射线衍射(XRD)、透射电子显微镜(TEM)分析样品的结构和微观形貌,使用振动样品磁强计(VSM)研究镍纳米晶体的磁性能。XRD结果显示,样品为面心立方结构;TEM结果显示通过控制实验条件,... 通过微波辅助polyol法合成多种形态的镍纳米晶体,采用X射线衍射(XRD)、透射电子显微镜(TEM)分析样品的结构和微观形貌,使用振动样品磁强计(VSM)研究镍纳米晶体的磁性能。XRD结果显示,样品为面心立方结构;TEM结果显示通过控制实验条件,可以得到单分散的球状、链状、头发状镍纳米晶体。VSM分析结果,表明头发状镍纳米晶体具有典型的铁磁性。 展开更多
关键词 镍纳米晶体 微波辅助polyol 可控合成
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Promotion of Ni/MCM-41 Catalyst for Hydrogenation of Naphthalene by co-Impregnation with Polyols
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作者 仇松柏 翁育靖 +3 位作者 李玉萍 马龙隆 张琦 王铁军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期433-438,J0001,共7页
The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols (ethylene glycol, glycerol, xylitol, sorbitol and glucose), were investigated by hydrogenation of naphthalene. Compare... The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols (ethylene glycol, glycerol, xylitol, sorbitol and glucose), were investigated by hydrogenation of naphthalene. Compared with the conventional wetness impregnation, addition of moderate polyols into the metal nitrate support surface, resulting in formation of persion of the active phase and significant aqueous solution could enhance interaction with very small NiO particle size (〈5 nm), high discatalytic activity. Particle size of Ni^0 decreased from 36.1 nm to below 5 nm; meanwhile the complete hydrogenation of naphthalene was dependent on the Ni^0 particle size. The hydrogenation activities of the catalysts prepared by co-impregnation with polyols were very high with 100% conversion even at iow temperature of 55 ℃. 展开更多
关键词 Ni/MCM-41 co-Impregnation Naphthalene hydrogenation polyolS
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微波辅助polyol法制备形貌各异的纳米镍
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作者 章成文 刘先松 《新乡学院学报》 2010年第3期44-46,共3页
采用微波辅助polyol法成功制备了直径在5~10nm、100~180nm的单分散Ni颗粒,研究了其磁性能。采用X线衍射仪(XRD)、透射电子显微镜(TEM)分析了样品的结构和微观形貌,使用振动样品磁强计(VSM)研究了镍纳米晶体的磁性能。XRD显示该样品是... 采用微波辅助polyol法成功制备了直径在5~10nm、100~180nm的单分散Ni颗粒,研究了其磁性能。采用X线衍射仪(XRD)、透射电子显微镜(TEM)分析了样品的结构和微观形貌,使用振动样品磁强计(VSM)研究了镍纳米晶体的磁性能。XRD显示该样品是面心立方结构,TEM观察结果表明样品金属镍呈现毛茸茸的头发结构,VSM测试结果表明Ni纳米颗粒具有典型的铁磁性。 展开更多
关键词 单分散Ni球 微波辅助polyol 磁性能
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Polyol法制备PEO-PPO-PEO包裹的多功能CoFeAu纳米粒子(英文) 被引量:1
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作者 邵红琴 张晓燕 +2 位作者 侯澎 吴君华 刘红玲 《化学研究》 CAS 2013年第3期242-246,共5页
采用Polyol合成法,以三嵌段共聚物PEO-PPO-PEO为表面活性剂,以1,2-十六烷二醇为还原剂,乙酰丙酮钴(Ⅱ)、乙酰丙酮铁(Ⅱ)和醋酸金为前驱体,成功合成了CoFeAu纳米粒子.傅立叶变换红外光谱(FT-IR)分析证实了共聚物PEO-PPO-PEO包裹在CoFeAu... 采用Polyol合成法,以三嵌段共聚物PEO-PPO-PEO为表面活性剂,以1,2-十六烷二醇为还原剂,乙酰丙酮钴(Ⅱ)、乙酰丙酮铁(Ⅱ)和醋酸金为前驱体,成功合成了CoFeAu纳米粒子.傅立叶变换红外光谱(FT-IR)分析证实了共聚物PEO-PPO-PEO包裹在CoFeAu纳米颗粒表面,X射线衍射仪(XRD)测试得出该纳米粒子是面心立方晶体结构、晶格参数为0.406nm、结晶性能好.紫外可见近红外分光光度计吸收光谱仪和振动样品磁强计(VSM)测试证明了该纳米粒子兼具良好的光学和磁学特性.该多功能CoFeAu纳米粒子有望在催化材料、磁材料、光电和生物医药等方面发挥有益作用. 展开更多
关键词 polyol合成法 CoFeAu纳米粒子 光学和磁学性能
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Epalrestat protects against diabetic peripheral neuropathy by alleviating oxidative stress and inhibiting polyol pathway 被引量:42
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作者 Qing-rong Li Zhuo Wang +8 位作者 Wei Zhou Shou-rui Fan Run Ma Li Xue Lu Yang Ya-shan Li Hong-li Tan Qi, ng-hua Shao Hong-ying Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第2期345-351,共7页
Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by... Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway. 展开更多
关键词 nerve regeneration peripheral nerve injury STREPTOZOTOCIN reactive oxygen species diabetic neuropathy oxidative stress aldosereductase antioxidant enzymes polyol pathway aldose reductase inhibitor superoxide dismutase CATALASE glutathione peroxidase rats NSFCgrant neural regeneration
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Preparation and characterization of tung oil-based flame retardant polyols 被引量:3
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作者 Wei Zhou Puyou Jia +1 位作者 Yonghong Zhou Meng Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2664-2671,共8页
Three kinds of tung oil-based structural flame retardants polyols(TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycer... Three kinds of tung oil-based structural flame retardants polyols(TOFPs) were prepared by new methods in this paper. First, tung oil was used to produce monoglyceride and diglyceride by transesterification with glycerol by sodium methoxide. The products after transesterification were epoxidized by peracetic acid which was in-situ generated from acetic acid and hydrogen peroxide in the presence of sulfuric acid catalyst. And then, TOFPs were prepared from epoxidized alcoholysis tung oil(EGTO) with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO), diethyl phosphate(DEP) and diethanolamine(DEA) by ring-opening reactions, respectively. GPC was used to evaluate the conversion rate, at optimum reaction conditions, selectivity for monoglyceride in transesterification. The influence of different parameters such as temperature, mole ratio or mass ratio on the conversion rate of transesterification and epoxidation were investigated. The molecular structures of TOFPs were characterized by FTIR and ~1HNMR. Finally, tung oil-based polyurethane foams(TOPUFs) were prepared by a one-shot process using TOFPs with polyisocyanate. The LOI values of TOPUFs whose content of DOPO-EGTO,DEP-EGTO and DEA-EGTO were 100 wt% can reach to 26.2%, 25.1%, and 24.4%, respectively. 展开更多
关键词 Tung OIL TRANSESTERIFICATION EPOXIDATION FLAME retardant polyolS
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Self-reducing bifunctional Ni-W/SBA-15 catalyst for cellulose hydrogenolysis to low carbon polyols 被引量:4
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作者 Zhuqian Xiao Qiuwei Ge +4 位作者 Chuang Xing Chengjun Jiang Sheng Fang Jianbing Ji Jianwei Mao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第3期434-444,共11页
A series of self-reducing bifunctional Ni-W/SBA-15 catalysts were synthesized using biomass-based carbon source as the reducing agent without conventional further reduction step. The self-reducing catalysts were perfo... A series of self-reducing bifunctional Ni-W/SBA-15 catalysts were synthesized using biomass-based carbon source as the reducing agent without conventional further reduction step. The self-reducing catalysts were performed on the hydrogenolysis of cellulose to low carbon polyols. The effects of calcination temperature and metallic loading contents for cellulose hydrogenolysis reaction were investigated detailedly.The optimal calcination temperature was found to be 673 K by TG analysis. The active metal nanoparticles with a better dispersion were observed using SEM and element mapping technology. The yield of low carbon polyols using the catalyst with the receipt of 10%Ni-15%W/SBA-15-673 K can reach as high as68.14%, of which the ethylene glycol(EG) accounts for 61.04%. 展开更多
关键词 Cellulose HYDROGENOLYSIS Low carbon polyols Self-reducing catalyst
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Synthesis and electrochemical properties of Li_2MnSiO_4/C nanoparticles via polyol process 被引量:3
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作者 LIU Wengang XU Yunhua YANG Rong 《Rare Metals》 SCIE EI CAS CSCD 2010年第5期511-514,共4页
Carbon-coated lithium manganese silicate (Li2MnSiO4/C) nanoparticles were synthesized by polyol process. X-ray diffraction (XRD) patterns of the obtained materials exhibit a good fit with that of the Li2MnSiO4 pha... Carbon-coated lithium manganese silicate (Li2MnSiO4/C) nanoparticles were synthesized by polyol process. X-ray diffraction (XRD) patterns of the obtained materials exhibit a good fit with that of the Li2MnSiO4 phase. Field emission scanning electron microscopy (FESEM) images of the obtained samples show that the particle size is only tens of nanometers. The high resolution transmission electron microscopy (HRTEM) analysis shows that the Li2MnSiO4 nanoparticles are surrounded by a very thin film of amorphous carbon. The composite prepared through polyol process shows good performance as cathode materials in lithium cells at room temperature. The charge capacity of the Li2MnSiO4/C samples is 219 mAh/g (about 1.3 Li^+ per unit formula extracted), and the discharge capacity is 132 mAh/g (about 0.8 Li^+ per unit formula inserted) in the first cycle in the voltage range of 1.5-4.8 V. A good capacity cycling maintenance of 81.8% after 10 cycles was obtained. 展开更多
关键词 lithium ion batteries cathode materials electrochemical properties polyol process SILICATES
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Ehealth monitoring in irritable bowel syndrome patients treated with low fermentable oligo-, di-, mono-saccharides and polyols diet 被引量:7
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作者 Natalia Pedersen Zsuzsanna Vegh +5 位作者 Johan Burisch Lisbeth Jensen Dorit Vedel Ankersen Maria Felding Nynne Nyboe Andersen Pia Munkholm 《World Journal of Gastroenterology》 SCIE CAS 2014年第21期6680-6684,共5页
In the present study we report on changes in irritable bowel syndrome-severity scoring system (IBS-SSS) and irritable bowel syndrome-quality of life (IBS-QoL) in 19 IBS patients, aged 18 to 74 years (F/M: 14/5), durin... In the present study we report on changes in irritable bowel syndrome-severity scoring system (IBS-SSS) and irritable bowel syndrome-quality of life (IBS-QoL) in 19 IBS patients, aged 18 to 74 years (F/M: 14/5), during 12 wk registering their symptoms on the web-application (www.ibs.constant-care.dk). During a control period of the first 6-wk patients were asked to register their IBS-SSS and IBS-QoL on the web-application weekly without receiving any intervention. Thereafter, low fermentable oligo-, di-, mono-saccharides and polyols (FODMAP) diet (LFD) was introduced for the next 6 wk while continuing the registration. Though a small sample size a significant improvement in disease activity (IBS-SSS) was observed during both the control period, median: 278 (range: 122-377), P = 0.02, and subsequently during the LFD period, median: 151 (range: 29-334), P &#x0003c; 0.01. The IBS-QoL solely changed significantly during the LFD period, median: 67 (37-120), P &#x0003c; 0.01. The significant reduction in disease activity during the control period shows a positive effect of the web-application on IBS symptoms when presented as a &#x0201c;traffic light&#x0201d;. However adding the diet reduced IBS-SSS to &#x0003c; 150, inactive to mild symptoms. In the future results from larger scale trials are awaited. 展开更多
关键词 Irritable bowel syndrome Low fermentable oligo- di- mono-saccharides and polyols diet SELF-MANAGEMENT Disease-specific quality of life Disease activity
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Redox imbalance stress in diabetes mellitus: Role of the polyol pathway 被引量:27
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作者 Liang-jun Yan 《Animal Models and Experimental Medicine》 2018年第1期7-13,共7页
In diabetes mellitus, the polyol pathway is highly active and consumes approximately 30% glucose in the body. This pathway contains 2 reactions catalyzed by aldose reductase(AR) and sorbitol dehydrogenase, respectivel... In diabetes mellitus, the polyol pathway is highly active and consumes approximately 30% glucose in the body. This pathway contains 2 reactions catalyzed by aldose reductase(AR) and sorbitol dehydrogenase, respectively. AR reduces glucose to sorbitol at the expense of NADPH, while sorbitol dehydrogenase converts sorbitol to fructose at the expense of NAD+, leading to NADH production. Consumption of NADPH, accumulation of sorbitol, and generation of fructose and NADH have all been implicated in the pathogenesis of diabetes and its complications. In this review, the roles of this pathway in NADH/NAD+redox imbalance stress and oxidative stress in diabetes are highlighted. A potential intervention using nicotinamide riboside to restore redox balance as an approach to fighting diabetes is also discussed. 展开更多
关键词 diabetes MELLITUS FRUCTOSE NADH/NAD^+ oxidative STRESS polyol pathway redox IMBALANCE STRESS
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A Novel Sesquiterpene Polyol Ester from Celastrus Angulatus and its Antitumor Activities 被引量:2
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作者 Wei Ping YIN Tian Zeng ZHAO +2 位作者 Ling Jie GAO Da Peng ZOU Jian Xun KANG(Institute of Chemistry,Henan Academy of Sciences Zhengzhou 450003 Centre of Instrumental Analysis. Zhengzhou University. Zhengzhou 450052) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第6期487-490,共4页
A new sesquiterpene polyol ester was isolated from the leaves of Celastrus angulatus. Its structure was determined as 1 (beta), 2 (beta), 9 (a) -triacetoxy-8 (a) -((a) -hydroxyl-isobutyryloxy)-15-benzoyloxy-4 (a) -hyd... A new sesquiterpene polyol ester was isolated from the leaves of Celastrus angulatus. Its structure was determined as 1 (beta), 2 (beta), 9 (a) -triacetoxy-8 (a) -((a) -hydroxyl-isobutyryloxy)-15-benzoyloxy-4 (a) -hydroxy-dihydroagarofuran by means of NMR, MS and IR spectral analysis. Preliminary biological study on antitumor activity revealed that this compound showed strong nonselective cytotoxicity against four of the NCI panel cell lines. 展开更多
关键词 Celastrus angulatus sesquiterpene polyol ester NMR antitumor activities
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Polyol-Mediated Synthesis and Photoluminescent Properties of LaPO_4∶Eu ^( 3+) Nanoparticles 被引量:1
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作者 Wang Zhenling Qiao Ziwen +1 位作者 Quan Zewei Lin Jun 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期263-263,共1页
Eu^3+-doped LaPO4 nanoparticles were prepared by polyol method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermogravimetry-differential thermal analysis (... Eu^3+-doped LaPO4 nanoparticles were prepared by polyol method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), thermogravimetry-differential thermal analysis (TG-DTA), Uv-vis diffuse reflectance spectra (DRS), photoluminescence (PL) spectra and lifetime measurement. The results of XRD indicate that the as-prepared nanoparticles are crystallized well at 160 ℃ and assigned to the monoclinic monazite-structure of LaPO4 phase. The obtained LaPO4:Eu^3+ nanoparticles are spherical with narrow size distribution and the average size of 25 nm. 展开更多
关键词 LAPO4 polyol method NANOPARTICLE PHOTOLUMINESCENCE EUROPIUM rare earths
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Catalytic Conversion of Biomass-Derived Polyols into Para-xylene over SiO2-Modified Zeolites 被引量:2
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作者 Sheng-fei Wang Ming-hui Fan +1 位作者 Yu-ting He Quan-xin Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第4期513-520,I0003,共9页
This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromat... This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts. 展开更多
关键词 Biomass-derived polyols PARA-XYLENE Catalytic conversion SiO2-modified HZSM-5
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Optimisation of Bio-polyol Production from Cassava Residue Using Ethylene Glycol as the Liquefaction Reagent 被引量:2
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作者 KANG Jiaqing JIN Yanqiao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期945-949,共5页
Cassava residue was liquefied by using ethylene glycol(EG), ethylene carbonate, propylene carbonate and polyethylene glycol(molecular weight: 400 g/mol) as the liquefaction reagent respectively at the temperature of 1... Cassava residue was liquefied by using ethylene glycol(EG), ethylene carbonate, propylene carbonate and polyethylene glycol(molecular weight: 400 g/mol) as the liquefaction reagent respectively at the temperature of 130-170 ℃ with sulfuric acid as the catalyst. The influences of liquefaction parameters, such as the type of liquefaction reagents, mass ratio of EG/cassava residue, liquefaction temperature and time on the properties of the products were discussed. The optimum liquefaction conditions were obtained when the mass ratio of EG/cassava residue was 6:1(w/w), the liquefaction temperature was 150 ℃, the liquefaction time was3 h and the mass fraction of concentrated sulfuric acid/EG was 2.5 wt%. The hydroxyl numbers and residue content of the liquefied products at optimal conditions were 1 137 mgKOH/g and 0.43%, respectively. FT-IR spectrum showed that the liquefaction product of cassava residue was polyether polyol and could be used to prepare polyurethane material or alkyd resins. 展开更多
关键词 CASSAVA residue LIQUEFACTION bio-polyol ethylene GLYCOL
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