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Critical approaches in the catalytic transformation of sugar isomerization and epimerization after Fischer-History,challenges,and prospects

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Green Energy & Environment 2024年第3期9卷 435-453页

作者： Da-Ming Gao Xun Zhang haichao liu Hidemi Fujino Tingzhou Lei Fuan Sun Jie Zhu Taoli Huhe National-local Joint Engineering Research Center of Biomass Refine and High-Quality Utilization Changzhou UniversityChangzhou213164China Institute of Urban and Rural Mining Research Changzhou UniversityChangzhou213164China Changzhou Key Laboratory of Biomass Green Safe&High Value UtilizationChangzhou UniversityChangzhou213164China Beijing National Laboratory for Molecular Science College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Department of Rehabilitation Science Kobe University Graduate School of Health SciencesKobe654-0142Japan

The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and the synthesis of ***,high-fructose corn syrup(HFCS)is industrially produced in more than 10 million tons annually using immobilized glucose *** low-calorie saccharides such as tagatose and psicose,which are becoming popular sweeteners,have also been produced on a pilot scale in order to replace sucrose and ***,current catalysts and catalytic processes are still difficult to utilize in biomass conversion and also have strong substrate dependence in producing high-value,rare *** the specific reaction properties of saccharides and catalysts,since the pioneering discovery by Fischer,various catalysts and catalytic systems have been discovered or developed in attempts to extend the reaction pathways,improve the reaction efficiency,and to potentially produce commercial *** this review,we trace the history of sugar isomerization/epimerization reactions and summarize the important breakthroughs for each reaction as well as the difficulties that remain unresolved to date.

关键词： Rare sugars Isomerization Ketonization Epimerization Catalytic transformation

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Machine learning and bioinformatics to identify biomarkers in response to Burkholderia pseudomallei infection in mice

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BIOCELL 2024年第4期48卷 613-621页

作者： YAO FANG FEI XIA FEIFEI TIAN L EI QU FANG YANG JUAN FANG ZHENHONG HU haichao liu Department of Respiratory and Critical Care Medicine General Hospital of Center Theater of PLAWuhan430070China School of Medicine Wuhan University of Science and TechnologyWuhan430065China School of Life Science and Engineering Southwest Jiaotong UniversityChengdu611756China

Objective:In the realm of Class I pathogens,Burkholderia pseudomallei(BP)stands out for its propensity to induce severe *** the intricate interactions between BP and host cells is imperative for comprehending the dynamics of BP infection and discerning biomarkers indicative of the host cell response ***:mRNA extraction from BP-infected mouse macrophages constituted the initial step of our *** gene expression arrays,the extracted RNA underwent conversion into digital *** percentile shift method facilitated data processing,with the identiﬁcation of genes manifesting signiﬁcant differences accomplished through the application of the ***,a comprehensive analysis involving Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway was conducted on the differentially expressed genes(DEGs).Leveraging the ESTIMATE algorithm,gene signatures were utilized to compute risk scores for gene expression *** vector machine analysis and gene enrichment scores were instrumental in establishing correlations between biomarkers and macrophages,followed by an evaluation of the predictive power of the identiﬁed ***:The functional and pathway associations of the DEGs predominantly centered around G protein-coupled receptors.A noteworthy positive correlation emerged between the blue module,consisting of 416 genes,and the ***4,identiﬁed through support vector machine analysis among intersecting genes,indicated a robust interaction with macrophages,suggesting its potential as a robust ***4 exhibited commendable predictive efﬁcacy,with BP infection inducing its expression in both macrophages and mouse lung *** blotting in macrophages conﬁrmed a signiﬁcant upregulation of FZD4 expression from 0.5 to 24 h *** mouse lung tissue,FZD4 manifested higher expression in the cytoplasm of pulmonary epithelial cells in BP-infected lungs than in the

关键词： Burkholderia pseudomallei Microarray assay Machine learning Bioinformatics FZD4

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微点蚀损伤的研究进展与展望

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摩擦学学报（中英文） 2024年第5期44卷 715-728页

作者：赵景鑫姜程李维民刘海超栗心明青岛理工大学机械与汽车工程学院山东青岛266520 中国科学院兰州化学物理研究所固体润滑国家重点实验室甘肃兰州730000 淄博高端合成润滑材料创新中心山东淄博255000

微点蚀是高应力滑滚接触副在润滑油膜不能充分建立的条件下由于表面粗糙度的塑性变形引发的1种表面起源型疲劳损伤现象,常见于硬齿面齿轮、滚动轴承等关键机械零部件中,严重影响运动部件传动精度、服役寿命及可靠性.本文中重点调研了微... 详细信息

微点蚀是高应力滑滚接触副在润滑油膜不能充分建立的条件下由于表面粗糙度的塑性变形引发的1种表面起源型疲劳损伤现象,常见于硬齿面齿轮、滚动轴承等关键机械零部件中,严重影响运动部件传动精度、服役寿命及可靠性.本文中重点调研了微点蚀研究与润滑材料评价所用的试验方法、微点蚀的成因及其关键影响因素,总结了微点蚀形成所涉及的表面/次表面微裂纹萌生及可能的演化过程.从摩擦学角度给出了工程实践中抑制微点蚀的可行性措施,并对未来关于微点蚀的重点研究问题进行了展望.本文中对润滑界面微点蚀失效分析、表面合理润滑设计和润滑油品抗微点蚀的添加剂关键组分筛选与评定有一定指导意义.

关键词：微点蚀滑滚接触失效分析润滑材料润滑

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气腹针在单孔腹腔镜鞘状突高位结扎术中的应用

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中国微创外科杂志 2024年第2期24卷 150-153页

作者：康延杰刘海潮刘少朋孙建涛郑州大学附属洛阳中心医院泌尿外科洛阳471000 郑州大学附属洛阳中心医院肝胆疝外科洛阳471000

目的探讨气腹针法单孔腹腔镜鞘状突高位结扎术的应用价值。方法回顾性分析2021年1月~2023年3月气腹针法单孔腹腔镜鞘状突高位结扎术51例资料。用气腹针代替疝针行鞘状突高位结扎。结果手术均获成功,未增加辅助孔或中转开放手术。46... 详细信息

目的探讨气腹针法单孔腹腔镜鞘状突高位结扎术的应用价值。方法回顾性分析2021年1月~2023年3月气腹针法单孔腹腔镜鞘状突高位结扎术51例资料。用气腹针代替疝针行鞘状突高位结扎。结果手术均获成功,未增加辅助孔或中转开放手术。46例单侧手术时间6~15 min,(8.9±1.9)min;5例双侧手术时间13~19 min,(15.4±2.3)min。术后随访6个月,均无复发,无线结反应、阴囊水肿、阴囊血肿、医源性隐睾及睾丸萎缩等并发症发生。结论气腹针法单孔腹腔镜鞘状突高位结扎术具有单孔手术、单次穿刺、操作简便易行的优点,疗效确切,值得推广。

关键词：交通性鞘膜积液腹股沟斜疝单孔腹腔镜手术气腹针鞘状突

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Insights into support effects on Ce-Zr-O mixed oxide-supported gold catalysts in CO oxidation

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Journal of Energy Chemistry 2013年第1期22卷 98-106页

作者： Hongpeng Zhang haichao liu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species College of Chemistry and Molecular Engineering Peking University

Au]Cel_xZrxO2 catalysts （x = 0-0.8） were prepared by a deposition-precipitation method using Cel_xZrxO2 nanoparticles as supports with variable Ce and Zr contents. Their structures were characterized by complimentary means such as X-ray diffraction, Raman, scanning trans- mission electron microscopy and X-ray photoelectron spectroscopy （XPS）. These Au catalysts possessed similar sizes and crystalline phases of Cel_xZrzO2 supports as well as similar sizes and oxidation states of Au nanoparticles. The oxidation state of Au nanoparticles was dominated by Au~ especially in CO oxidation. Their activities were examined in CO oxidation at different temperatures in the range of 303-333 K. The CO oxidation rates normalized per Au atoms increased with the increasing Ce contents, and reached the maximum value over Au/CeO2. Such change was in parallel with the change in the oxygen storage capacity values, i.e. the amounts of active oxygen species on Au/Cel_zZrzO2 catalysts. The excellent correlation between the two properties of the catalysts suggests that the intrinsic support effects on the CO oxidation rates is related to the effects on the adsorption and activation of O2 on Au/Cel_xZrxO2 catalysts. Such understanding on the support effects may be useful for designing more active Au catalysts, for example, by tuning the redox properties of oxide supports.

关键词： gold catalyst ceria-zirconia support CO oxidation oxygen storage capacity support effect

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废旧聚氨酯泡沫醇解产物作为再生剂实现废橡胶的力化学再生

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高分子材料科学与工程 2024年第4期40卷 119-126页

作者：刘功旭白立臣郭守运柴海林渐兴澳赵金阳刘可鑫郭磊刘海超青岛科技大学机电工程学院山东青岛266061

近年来,废聚氨酯和废橡胶产量呈上升趋势,其资源化循环利用成为研究热点。文中使用丙二醇作为醇解剂在不同温度下分解聚氨酯泡沫,并利用聚氨酯醇解产物作为再生剂实现了废橡胶的力化学再生。醇解产物下层液(PAPL)含有较多的胺类基团,可... 详细信息

近年来,废聚氨酯和废橡胶产量呈上升趋势,其资源化循环利用成为研究热点。文中使用丙二醇作为醇解剂在不同温度下分解聚氨酯泡沫,并利用聚氨酯醇解产物作为再生剂实现了废橡胶的力化学再生。醇解产物下层液(PAPL)含有较多的胺类基团,可与橡胶再生过程中产生的自由基结合,提高橡胶的脱硫程度,从而提高再生胶(RRs)的力学性能。与只填加活化剂的RRs相比,在原有活化剂填加份数的基础上,加入PAPL可缩短RRs的最佳硫化时间,提高交联密度。使用180℃制备的聚氨酯醇解产物下层液,RRs硫化橡胶的综合性能最好,拉伸强度达到15.6MPa,断裂伸长率达到325.5%。该方法实现了废聚氨酯和废橡胶的双重高价值回收,应用前景广阔。

关键词：聚氨酯醇解废橡胶回收再生试剂高价值回收

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MVR蒸发器及蒸汽压缩机应用比较

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化工设计 2024年第2期34卷 35-36,2页

作者：刘殿宇刘海超华禹乳品机械制造有限公司黑龙江安达151400 上海汽车电驱动有限公司上海201801

MVR蒸发器所选用的蒸汽压缩机有离心蒸汽压缩机、罗茨蒸汽压缩机及单级螺杆蒸汽压缩机,前两种是近十几年来普遍采用的压缩机,最后一种是近几年才开始在MVR蒸发器中应用,其最大的特点是在蒸发器工作过程中温升较高,MVR蒸发器是将二次蒸... 详细信息

MVR蒸发器所选用的蒸汽压缩机有离心蒸汽压缩机、罗茨蒸汽压缩机及单级螺杆蒸汽压缩机,前两种是近十几年来普遍采用的压缩机,最后一种是近几年才开始在MVR蒸发器中应用,其最大的特点是在蒸发器工作过程中温升较高,MVR蒸发器是将二次蒸汽通过蒸汽压缩机全部压缩作为加热热源,去蒸发器壳程加热蒸发料液,MVR蒸发器要连续进料连续出料,必须将物料加热至沸点或沸点以上的温度。实际应用中,由于物料进入蒸发器前预热温度较低,有的没有达到沸点或沸点以上的温度,导致不能及时启动压缩机,甚至由于二次蒸汽量不足,压缩机工作过程中出现喘振的事例比较多见;有些蒸发器比较小,使用单位又没有蒸汽热源,大多都是制造厂家提供蒸汽发生器,有的蒸汽发生器产气量过小,致使预热温度迟迟达不到要求温度,也就不能按时启动蒸汽压缩机,这样的事例也比较多见。料液进入蒸发器前的预热效果直接关系到MVR蒸发器能否正常工作,即便预热效果良好,在生产过程中由于沸点升高、热损耗及压缩机本身的需要,也必须补充一定量的额外蒸汽,否则蒸发很难正常进行。要达到理想的蒸发状态,在诸多影响因素中,蒸汽压缩机喷淋水有多少气化参与了加热,也很重要。本文就MVR蒸发器及三种压缩的应用进行阐述,为同类应用提供参考。

关键词： MVR蒸发器蒸汽压缩机应用

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环醚直接双羰基化合成α,ω-二元羧酸

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Chinese Journal of Catalysis 2024年第1期56卷 122-129页

作者：马长坡赖楹赵天歌张小炫刘海超杨维冉南昌大学化学化工学院江西南昌330031 北京大学化学与分子工程学院北京分子科学国家研究中心北京100871

二元羧酸是制备聚酰胺、聚酯和聚氨酯的重要中间体,其传统合成途径具有一定的局限性.以己二酸为例,其主要工业生产工艺是利用硝酸氧化KA油,该方法存在KA油产量低和产生大量温室气体N2O等问题.因此,探索工艺绿色、原子有效和采用可再生... 详细信息

二元羧酸是制备聚酰胺、聚酯和聚氨酯的重要中间体,其传统合成途径具有一定的局限性.以己二酸为例,其主要工业生产工艺是利用硝酸氧化KA油,该方法存在KA油产量低和产生大量温室气体N2O等问题.因此,探索工艺绿色、原子有效和采用可再生原料的二元羧酸制备方法具有重要意义.环醚和多元醇很容易从生物质原料中得到,以它们为原料,通过双羰基化直接制备二元羧酸,是一种非常有潜力的反应途径.但目前大多数文献报道由环醚或多元醇通过羰基化反应生成的产物主要是C+1单羧酸.本课题组一直致力于碘催化生物质衍生的多元醇的加氢脱氧,研究发现,在特定的反应条件下,多元醇可以选择性地形成多碘取代化合物的中间体.受此启发,本文报道了一种由环醚或多元醇形成二碘代物中间体,然后直接通过双羰基化反应生成对应的C+2二羧酸的新策略.由于己二酸是最重要的二元羧酸之一,且四氢呋喃(THF)可以从丰富的生物质衍生的糠醛中获得,本文重点研究了通过双羰基化反应直接利用THF合成己二酸.在优化的反应条件下,以铑盐为催化剂,碘为促进剂,乙酸和水为混合溶剂,在170℃,CO和H_(2)条件下,THF可以84%的产率转化为己二酸.循环实验结果表明,该催化体系在5次循环后仍能够稳定运行.该催化体系不仅适用于各种环醚,也适用于不同的伯二醇合成对应的C+2α,ω-二元羧酸.通过对反应中间体进行检测以及控制实验研究发现,选择性生成1,4-二碘丁烷中间体是进一步双羰基化制备己二酸的关键,而生成烯烃中间体和单碘代物中间体是形成副产物戊酸的主要原因.在实验结果和文献研究基础上,提出了THF转化为己二酸的反应机理.在反应中,活性铑常以Rh(I)的形式存在,并且从质谱中观察到了[Rh(CO)_(2)I_(2)]−阴离子,它可以在羰基化条件下由不同的铑前体(例如RhCl_(3))经过CO和碘还原后衍生.具体反应步骤为,首先铑催化剂催化H2和I2生成HI,然后THF与HI反应生成1,4-二碘丁烷中间体,此中间体经过铑催化活化在两端分别进行羰基化反应,最终生成产物己二酸.通过质谱检测到两个推测的中间体,进一步证实该反应机理.综上,本文为己二酸、戊二酸和其他重要的二羧酸(如1,7-庚二酸和1,8-辛二酸)的有效合成提供了一种新策略,为二元羧酸的高效、绿色合成提供参考.

关键词： α,ω-二元羧酸双羰基化环醚多元醇己二酸

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Hydroxyl radicals-mediated oxidative cleavage of the glycosidic bond in cellobiose by copper catalysts and its application to low-temperature depolymerization of cellulose

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Chinese Journal of Catalysis 2020年第7期41卷 1073-1080页

作者： Fangwei Gu haichao liu Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

As the most abundant source of biomass in nature for sustainable production of fuels and chemicals,efficient depolymerization of cellulose under mild conditions,due to the difficulty in selective cleavage of itsβ-1,4-glycosidic bonds,still remains ***,we report a novel method for oxidative cleavage of the glycosidic bonds by free *** by the cellobiose reaction,it was found that·OH radicals,generated from the decomposition of H2O2 catalyzed by CuSO4 or CuO/SiO2,were efficient for selective conversion of cellobiose to glucose and gluconic acid at a low temperature of 333 K,and their selectivities reached 30.0%and 34.6%,respectively,at 23.4%cellobiose *** radicals,such as·SO4?,also exhibited high efficacy in the cellobiose *** studies suggest that the oxidative cleavage of theβ-1,4-glycosidic bond by the free radicals involve formation of the carbon radical intermediate via abstraction of the H atom dominantly at the C1 *** this oxidative mechanism,treatment of microcrystalline cellulose with·OH by impregnation with H2O2 and CuSO4 catalyst at 343 K led to significant enhancement in its hydrolysis *** results demonstrate the effectiveness of this new method in the oxidative cleavage of glycosidic bonds,and its viability for the efficient depolymerization of cellulose at low temperatures,which can be further improved,for example,by exploring new free radicals and optimizing their reactivity and selectivity.

关键词： Cellulose depolymerization Cellobiose Hydroxyl radical Oxidative cleavage Glycosidic bond

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Base-free aerobic oxidation of glycerol on TiO_2-supported bimetallic Au–Pt catalysts

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Journal of Energy Chemistry 2015年第5期24卷 669-673页

作者： Yihong Shen Yuming Li haichao liu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species College of Chemistry and Molecular Engineering Peking University

The aerobic oxidation of glycerol provides an economically viable route to glyceraldehyde, dihydroxyacetone and glyceric acid with versatile applications, for which monometallic Pt, Au and Pd and bimetallic Au-Pt, Au- Pd and Pt-Pd catalysts on TiO2 were examined under base-free conditions. Pt exhibited a superior activity relative to Pd, and Au-Pd and Pt-Pd while Au was essentially inactive. The presence of Au on the Au-Pt/TiO2 catalysts led to their higher activities （normalized per Pt atom） in a wide range of Au/Pt atomic ratios （i.e. 1/3-7/1 ）, and the one with the Au/Pt ratio of 3/1 exhibited the highest activity. Such promoting effect is ascribed to the increased electron density on Pt via the electron transfer from Au to Pt, as characterized by the temperature-programmed desorption of CO and infra-red spectroscopy for CO adsorption. Meanwhile, the presence of Au on Au-Pt/TiO2, most like due to the observed electron transfer, changed the product selectivity, and facilitated the oxidation of the secondary hydroxyl groups in glycerol, leading to the favorable formation of dihydroxyacetone over glyceraldehyde and glyceric acid that were derived from the oxidation of the primary hydroxyl groups. The synergetic effect between Au and Pt demonstrates the feasibility in the efficient oxidation of glycerol to the targeted products, for example, by rational tuning of the electronic properties of metal catalysts.

关键词： Glycerol aerobic oxidation Glyceraldehyde Dihydroxyacetone Bimetallic Au-Pt catalyst Synergetic effect

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