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Microwave assisted liquefaction of wheat straw alkali lignin for the production of monophenolic compounds

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Journal of Energy Chemistry 2015年第1期24卷 72-76页

作者： xinping ouyang Guodian Zhu Xiangzhen Huang Xueqing Qiu School of Chemistry & Chemical Engineering South China University of Technology

The microwave assisted liquefaction process of wheat straw alkali lignin was investigated to obtain monophenolic compounds as the precursor of bio-fuel. It is found that the total yield of monophenolic compounds is significantly improved under microwave irradiation, reaching 15.77% under a relatively mild liquefaction condition of 10 wt% H2SO4 as the catalyst, 10 wt% phenol as the hydrogen-donor reagent at 120 ℃ for 40 rain. Compared with conventional thermal liquefaction process, microwave irradiation promotes the cleavage of C-C bonds, which gives an extra 29% of Caryl-Cα bond cleavage, and increases the yield of monophenolic compounds from 0.92% to 13.61% under the same conditions. The excessive temperature and prolonged time under microwave irradiation will promote the recondensation of degraded lignin fragments, so the key to obtain high yield of monophenolic compounds is to avoid the recondensation reaction. The selected solid catalyst promotes the dissociation of methoxy groups, and the addition of phenol into liquefaction can only slightly improve the yield of monophencolic compounds.

关键词： lignin liquefaction degradation monophenolic compounds microwave irradiation

Oxidative depolymerization of lignin improved by enzymolysis pretreatment with laccase

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Journal of Energy Chemistry 2018年第3期27卷 801-805页

作者： Yuan Zhu xinping ouyang Ying Zhao Linfeng Jiang Haijun Guo Xueqing Qiu School of Chemistry and Chemical Engineering South China University of TechnologyGuangzlzou 510640duangdongChino

A new lignin depolymerization approach for improving the yield of aromatic monomers（YAM） by enzymolysis pretreatment was investigated, in which lignin was pretreated with laccase followed by oxidative depolymerization. It was found that lignin depolymeirzation was enhanced significantly by enzymolysis. The oxidative depolymerization contributed to 21.37% of YAM after the enzymolysis pretreatment,whereas the conventional oxidative depolymerization only gave 14.10% of YAM. The addition of ethanol in enzymatic pretreatment process improved the efficiency of enzymolysis, which effectively improved the solubility of pretreated lignin and depolymerization degree（DD） of lignin. The enzymolysis pretreatment increased the content of syringyl（S） style aromatic monomers, which hindered the recondensation among polymerized products. As lignin has low solubility in acidic aqueous solution, ethanol was added into enzymolysis system to improve the efficiency. However, the enzymolysis of lignin should be carried out for a limited period of time to prevent the inactivation of laccase.

关键词： Lignin Depolymerization Enzymolysis Pretreatment Aromatic monomer

氮掺杂碳包覆FeCoNi颗粒的合成及催化甘油脱氢制备乳酸

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广东石油化工学院学报 2024年第1期34卷 29-32,39页

作者：董小瑨欧阳新平谭华华南理工大学化学与化工学院广东广州510640 广东石油化工学院化学学院广东茂名525000

乳酸作为一种生物质基平台化学品,是合成可生物降解聚合物的理想原料。本文通过一锅法合成了氮掺杂碳包覆FeCoNi合金催化剂。TEM结果表明FeCoNi@NC纳米材料为核壳结构,过渡金属核在热解过程中催化非晶碳石墨化,有利于金属纳米颗粒向碳... 详细信息

乳酸作为一种生物质基平台化学品,是合成可生物降解聚合物的理想原料。本文通过一锅法合成了氮掺杂碳包覆FeCoNi合金催化剂。TEM结果表明FeCoNi@NC纳米材料为核壳结构,过渡金属核在热解过程中催化非晶碳石墨化,有利于金属纳米颗粒向碳层之间的电子转移,从而提升催化活性。FeCoNi@NC在催化甘油脱氢反应中表现出优异的催化活性,在220℃时甘油转化率和乳酸的选择性分别达到98.1%和95.6%。另外,外层碳壳的保护作用抑制了合金颗粒的浸出和失活,FeCoNi@NC在连续5次循环使用后仍能保持稳定。这种催化系统将生物柴油副产物甘油升级为高值乳酸提供了一种高效经济的方法借鉴。

关键词：甘油无受体脱氢乳酸碳包覆 FeCoNi@NC

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Review of the evolution and prevention of friction,wear,and noise for water-lubricated bearings used in ships

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Friction 2024年第1期12卷 1-38页

作者： Zhuo ZHANG Wu ouyang Xingxin LIANG xinping YAN Chengqin YUAN Xincong ZHOU Zhiwei GUO Conglin DONG Zhenglin LIU Yong JIN Jinhua XIAO School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Reliability Engineering Institute National Engineering Research Center for Water Transport SafetyWuhan 430063China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430063China East Lake Laboratory Wuhan 420202China

With the development of green tribology in the shipping industry,the application of water lubrication gradually replaces oil lubrication in stern bearings and thrust *** terms of large-scale and high-speed ships,water-lubricated bearings with high performance are more strictly ***,due to the lubricating medium,water-lubricated bearings have many problems such as friction,wear,vibration,noise,*** review focuses on the performance of marine water-lubricated bearings and their failure prevention ***,the research of marine water-lubricated bearings is reviewed by discussing its lubrication principle,test technology,friction and wear mechanism,and friction noise generation *** performance enhancement methods have been overviewed from structure optimization and material ***,the potential problems and the perspective of water-lubricated bearings are given in detail.

关键词： water-lubricated bearings lubrication principles test techniques friction and wear friction noise evolution and prevention

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劣质原油的电脱盐工艺优化

广东石油化工学院学报 2024年第3期34卷 21-26,38页

作者：彭艳陈宏孔辰泽林健杨琬婷谭伟红程丽华欧阳新平范钦臻华南理工大学化学与化工学院广东广州510641 广东石油化工学院化学工程学院广东茂名525000 中国石油化工股份有限公司茂名分公司广东茂名525000

以纳波-奥瑞特-拉帕混合原油为对象,考察了破乳剂类型、破乳剂用量、混合强度、电脱温度、电场强度和电脱级数对电脱盐脱水效率的影响,确定了静态试验评价阶段最佳工艺条件:40μg/g的破乳剂用量、1200 r/min的混合强度、120℃的电脱温度... 详细信息

以纳波-奥瑞特-拉帕混合原油为对象,考察了破乳剂类型、破乳剂用量、混合强度、电脱温度、电场强度和电脱级数对电脱盐脱水效率的影响,确定了静态试验评价阶段最佳工艺条件:40μg/g的破乳剂用量、1200 r/min的混合强度、120℃的电脱温度、1200 V/cm的电场强度以及二级电脱级数。在小试确定工艺参数基础上,通过中试阶段现场设备的调试,使得脱后原油含盐(NaCl)的质量分数为2.87 mg/L,油中含水质量分数为0.15%,降至工业标准范围内。

关键词：电脱盐破乳剂工艺优化劣质原油

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Oxidative Degradation of Soda Lignin Assisted by Microwave Irradiation

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Chinese Journal of Chemical Engineering 2010年第4期18卷 695-702页

作者：欧阳新平林再雄邓永红杨东杰邱学青 School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou 510640China

The effects of oxidant dosage,oxidation temperature and time on the degradation of soda lignin by hydrogen peroxide with and without the presence of microwave irradiation were *** is found that the oxidative degradation of lignin includes the cleavage of ether bond inβ-O-4 structure,the partial destruction of aromatic ring,and the re-condensation of the degraded *** to the conventionally heated oxidation of lignin,the microwave irradiation efficiently facilitates the degradation of the lignin with high molecular weight and the re-condensation of that with low molecular weight at a low oxidant dosage,low oxidation temperature,or a short oxidation time,which leads to the formation of the degraded lignin with narrower molecular weight distribution and lower molecular ***,the lignin degraded in the presence of microwave irradiation has the characteristics of higher content of phenolic hydroxyl group,lower content of methoxyl group,and lower degree of condensation,which enhances the reactivity of ***,the oxidative degradation of lignin assisted by microwave irradiation may be a new pretreatment approach for efficiently utilizing the soda lignin.

关键词： oxidation degradation soda lignin microwave irradiation

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3种管内强化管沸腾换热性能对比

化工学报 2015年第6期66卷 2076-2081页

作者：欧阳新萍陈静竹李泰宇上海理工大学制冷与低温工程研究所上海200093 电装(中国)投资有限公司上海技术中心上海201108

对3种不同螺纹结构的强化管的管内沸腾换热性能进行对比实验研究,采用R22为实验工质。3种强化管的内径和外径相同,分别为6.9 mm和7.92 mm;管外均为光滑表面,管内的强化结构参数则不同：螺纹的螺旋角变化范围为14°~18°,螺纹高为0.15~0.... 详细信息

对3种不同螺纹结构的强化管的管内沸腾换热性能进行对比实验研究,采用R22为实验工质。3种强化管的内径和外径相同,分别为6.9 mm和7.92 mm;管外均为光滑表面,管内的强化结构参数则不同：螺纹的螺旋角变化范围为14°~18°,螺纹高为0.15~0.22 mm,螺纹槽宽度为0.1~0.2 mm。在给定进口和出口制冷剂的状态下,通过改变管内工质的质量流速,测试3根强化管的换热特性与质量流速的关系,并进行性能对比。实验结果表明：3种螺纹管管内沸腾传热系数分别比光管高出60%~80%,80%~120%和80%。分析认为,当流动处于层状流或者层状流与环状流的过渡区时,较大的螺旋角有利于换热;当流体处于环状流时,较多的螺纹头数有利于换热。

关键词：热力学传热气液两相流沸腾内螺纹管

R410A、R404A、R407C在水平强化换热管外的凝结换热

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化工进展 2017年第2期36卷 481-486页

作者：欧阳新萍舒涛刘冰翛上海理工大学能源与动力工程学院上海200093

研究了R410A、R404A、R407C在水平强化管外的凝结换热,并进行了换热性能的对比。实验管为常用的管内螺纹、管外斜翅的三维低肋管。应用威尔逊图解法对实验数据进行处理,得到管内对流换热系数并给出Dittus-Boelter形式的强化管管内对流... 详细信息

研究了R410A、R404A、R407C在水平强化管外的凝结换热,并进行了换热性能的对比。实验管为常用的管内螺纹、管外斜翅的三维低肋管。应用威尔逊图解法对实验数据进行处理,得到管内对流换热系数并给出Dittus-Boelter形式的强化管管内对流换热关联式,再根据热阻分离的方法得到管外凝结换热系数。结果表明,在相同换热参数下,凝结换热系数大小依次为R410A、R404A、R407C。3种制冷工质应用于该强化换热管的换热增强倍率分别在9.53~14.07、6.81~11.48和3.23~5.28的范围。而R410A、R404A和R407C在强化管内的强化倍率分别为1.77、1.73和1.76,三者相差不大。R410A管外凝结换热系数随着壁面过冷度的增大而减小,与单一制冷工质这一冷凝特性相同;而R404A和R407C与R410A不同,随着壁面过冷度的增大,管外凝结换热系数增大,这主要是非共沸制冷工质管外凝结过程存在的气膜热阻所致。

关键词：凝结换热强化换热混合制冷剂强化管

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制冷换热器双侧强化换热管的实验方法对比

制冷学报 2023年第6期44卷 61-68页

作者：苏博文欧阳新萍上海理工大学能源与动力工程学院上海200093

大型制冷系统中的换热管通常采用管内、管外表面双侧强化结构,因不便在壁面布置温度传感元件,双侧强化管需要特别的实验方法来测定其性能,包括Wilson图解法(WPM)、修正Gnielinski公式法(MGF)、Wilson-Gnielinski公式法(W-GF)。不同的方... 详细信息

大型制冷系统中的换热管通常采用管内、管外表面双侧强化结构,因不便在壁面布置温度传感元件,双侧强化管需要特别的实验方法来测定其性能,包括Wilson图解法(WPM)、修正Gnielinski公式法(MGF)、Wilson-Gnielinski公式法(W-GF)。不同的方法有各自的应用场合和使用局限性。本文针对双侧强化管提出一种便于应用的新方法,称为待定指数法(UEM),通过线性拟合和优化得到关联式中的待定参数,可有效分离管内、管外对流换热表面传热系数。在双侧强化管上进行了R134a管外蒸发、水管内流动的两组实验,以此对包含新方法的4种实验方法进行应用对比。结果表明:4种实验方法得到的强化管管内、管外对流换热表面传热系数的强化倍率分别在2.88~3.23、3.15~3.54之间,不同方法得到的管内、管外对流换热表面传热系数差异分别在15%、11%以内。4种实验方法可根据不同的应用条件选择使用,UEM限制条件少、应用方便,是一种更加高效、准确的实验方法。

关键词：传热系数实验方法制冷换热器双侧强化管

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