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防风均一多糖SP800301的化学结构研究

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北京中医药大学学报 2024年第6期47卷 853-862页

作者：王欣钰范海涛何新阳孙萌姜艳艳刘斌北京中医药大学中药学院北京102488 北京电子科技职业学院生物工程学院国家中医药管理局“中药经典名方有效物质发现”重点研究室

目的对从防风中分离得到的均一多糖SP800301进行结构解析,确定化学结构。方法采用二乙氨基乙基(DEAE)-纤维素、葡聚糖凝胶G-75等柱色谱法,分离纯化防风多糖;采用电喷雾串联质谱、气相色谱质谱联用、核磁共振等技术,对分离得到的防风均... 详细信息

目的对从防风中分离得到的均一多糖SP800301进行结构解析,确定化学结构。方法采用二乙氨基乙基(DEAE)-纤维素、葡聚糖凝胶G-75等柱色谱法,分离纯化防风多糖;采用电喷雾串联质谱、气相色谱质谱联用、核磁共振等技术,对分离得到的防风均一多糖SP800301的分子量分布、单糖组成、寡糖片段、糖残基类型和糖苷键连接方式等进行分析,确定结构;采用电子显微镜和原子力显微镜扫描法表征防风均一多糖SP800301的外貌特点。结果防风多糖SP800301均一性良好,分子量为9.1×10~4g/mol,糖醛酸含量52.72%,由鼠李糖、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为4.3∶58.1∶25.4∶5.0∶7.3。主要以聚半乳糖醛酸为主链,支链由鼠李糖、半乳糖醛酸、半乳糖、葡萄糖和阿拉伯糖组成,其中,阿拉伯糖在支链末端,糖链中部分半乳糖醛酸形成了甲酯。结论明确了防风中均一多糖SP800301的化学结构,丰富了防风中多糖的化学成分内涵,为进一步研究防风多糖的免疫调节作用机制奠定基础,为防风在临床的应用提供科学依据。

关键词：防风多糖化学结构半乳糖醛酸阿拉伯糖物质基础

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防风中1个新多糖的结构及免疫调节活性研究

中草药 2024年第4期55卷 1089-1099页

作者：何新阳范海涛孙萌李洁夏青姜艳艳刘斌北京中医药大学中药学院北京电子科技职业学院生物工程学院齐鲁工业大学(山东省科学院)生物研究所国家中医药管理局“中药经典名方有效物质发现”重点研究室

目的对防风Saposhnikovia divaricata中分离得到均一多糖的结构及其免疫调节活性进行研究。方法采用DEAE-纤维素、Sephadex G-75等柱色谱法，对防风多糖进行系统分离纯化，采用ESI-MSn、GC-MS、NMR等谱学技术，对分离得到的防风多糖SP... 详细信息

目的对防风Saposhnikovia divaricata中分离得到均一多糖的结构及其免疫调节活性进行研究。方法采用DEAE-纤维素、Sephadex G-75等柱色谱法，对防风多糖进行系统分离纯化，采用ESI-MSn、GC-MS、NMR等谱学技术，对分离得到的防风多糖SP800203的相对分子质量分布、单糖组成、寡糖片段、糖残基类型和糖苷键连接方式等进行分析，确定其结构。采用细胞实验和斑马鱼实验，研究防风多糖SP800203的免疫调节活性。结果从防风中分离得到防风多糖SP800203，糖醛酸质量分数为75.73%，相对分子质量约为7.14×104，由鼠李糖、半乳糖、阿拉伯糖和半乳糖醛酸组成，单糖物质的量比为2.8∶6.7∶6∶84.5。主链由半乳糖醛酸聚合而成，2条支链分别由阿拉伯糖、半乳糖醛酸、半乳糖、鼠李糖，以及阿拉伯糖、半乳糖醛酸、半乳糖聚合而成，二者分别通过β、α糖苷键与主链相连。防风多糖SP800203可以促进巨噬细胞一氧化氮、肿瘤坏死因子-α、白介素-1β和白介素-6的释放，增加斑马鱼的免疫细胞密度和巨噬细胞数量。结论防风多糖SP800203为从防风中分离得到的新的均一多糖，具有良好的免疫调节活性；研究结果为阐明防风免疫调节作用机制奠定了基础，为防风临床应用及进一步研究与开发提供科学依据。

关键词：防风多糖结构表征免疫调节半乳糖醛酸鼠李糖半乳糖阿拉伯糖

Aeration optimization through operation at low dissolved oxygen concentrations:Evaluation of oxygen mass transfer dynamics in different activated sludge systems

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Journal of Environmental Sciences 2017年第5期29卷 224-235页

作者： haitao fan Lu Qi Guoqiang Liu Yuankai Zhang Qiang fan Hongchen Wang Research Center for Low Carbon Technology of Water Environment Renmin University of China School of Environment Jinan University

In wastewater treatment plants（WWTPs）using the activated sludge process,two methods are widely used to improve aeration efficiency — use of high-efficiency aeration devices and optimizing the aeration control strategy. Aeration efficiency is closely linked to sludge characteristics（such as concentrations of mixed liquor suspended solids（MLSS）and microbial communities）and operating conditions（such as air flow rate and operational dissolved oxygen（DO）concentrations）. Moreover,operational DO is closely linked to effluent quality. This study,which is in reference to WWTP discharge class A Chinese standard effluent criteria,determined the growth kinetics parameters of nitrifiers at different DO levels in small-scale tests. Results showed that the activated sludge system could meet effluent criteria when DO was as low as 0.3 mg/L,and that nitrifier communities cultivated under low DO conditions had higher oxygen affinity than those cultivated under high DO conditions,as indicated by the oxygen half-saturation constant and nitrification ability. Based on nitrifier growth kinetics and on the oxygen mass transfer dynamic model（determined using different air flow rate（Q′air）and mixed liquor volatile suspended solids（MLVSS）values）,theoretical analysis indicated limited potential for energy saving by improving aeration diffuser performance when the activated sludge system had low oxygen consumption; however,operating at low DO and low MLVSS could significantly reduce energy consumption. Finally,a control strategy coupling sludge retention time and MLVSS to minimize the DO level was discussed,which is critical to appropriate setting of the oxygen point and to the operation of low DO treatment technology.

关键词： Aeration optimization Low dissolved oxygen nitrification Mixed liquor suspended solids Oxygen mass transfer Oxygen uptake rate

A matching algorithm between precursory 3D process model and 2D working procedure drawing based on subgraph isomorphism

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Science China(Technological Sciences) 2011年第7期54卷 1826-1832页

作者： HUANG Rui ZHANG ShuSheng fan haitao TAO Jun Key Laboratory of Contemporary Design and Integrated Manufacture Ministry of Education Northwest Polytechnical University Xi'an 710072 China

To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D working procedure drawings. First, the projection drawings of the precursory 3D process model are obtained, then the primitives are extracted and the attributed adjacency graph (AAG) is constructed. Finally, by taking the 2D working procedure drawing as the AAG, and the projection drawing as the whole AAG, the matching problem between precursory 3D process model and 2D working procedure drawings is translated into the problem of subgraph isomorphism. To raise the matching efficiency, the AAG is partitioned, and the vertexes of the graph are classified effectively using the vertex’s attributes. Experimental results show that this method is able to support exact match and the matching efficiency can meet the requirement of practical applications.

关键词： subgraph isomorphism process model three-dimensional model reconstruction working procedure drawing

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基于超声纵横波原位法的螺栓预紧力检测研究

工业加热 2024年第5期53卷 79-84页

作者：刘阳陈东范海涛刘飞贺瑞敏内蒙古电力(集团)有限责任公司内蒙古呼和浩特010030

针对超声纵横波的螺栓预紧力原位测量精度受几何层面和材料层面因素的影响,通过声弹力学的理论推导,提出了基于形状因子和材料因子的螺栓预紧力超声原位检测模型,并对多种规格、等级、厂商的螺栓的形状因子和材料因子的影响进行试验。... 详细信息

针对超声纵横波的螺栓预紧力原位测量精度受几何层面和材料层面因素的影响,通过声弹力学的理论推导,提出了基于形状因子和材料因子的螺栓预紧力超声原位检测模型,并对多种规格、等级、厂商的螺栓的形状因子和材料因子的影响进行试验。结果表明,本测量方法具有较高的拟合度,且可将形状因子λ<0.3作为适用条件。由此得出,通过测量验证了理论推导的正确性,定量地获得了各种因素对测量精度的影响范围,为建立纵横波虚拟标定曲线算法和数据库提供了坚实的基础。

关键词：超声纵横波原位法材料因子螺栓预紧力声弹力学理论

TOC estimation from logging data using principal component analysis

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能源地球科学(英文) 2023年第4期4卷 1-8页

作者： Yaxiong Zhang Gang Wang Xindong Wang haitao fan Bo Shen Ke Sun Petroleum Exploration and Production Research Institute SINOPECBeijing102206China Research Institute of Exploration and Development Xinjiang Oilfield CompanyKaramay834000China Materials and Equipment Center of CNPC Well Logging Company Xi'an710000China Geophysics and Oil Resource Institute Yangtze UniversityWuhan430010China Library Yangtze UniversityWuhan430010China

Total organic carbon(TOC)content is one of the most important parameters for characterizing the quality of source rocks and assessing the hydrocarbon-generating potential of *** Lucaogou Formation shale reservoirs in the Jimusaer Sag,Junggar Basin,NW China,is characterized by extremely complex lithology and a wide variety of mineral compositions with source rocks mainly consisting of carbonaceous mudstone and dolomitic *** logging responses of organic matter in the shale reservoirs is quite different from those in conventional *** show that the traditional△logR method is not suitable for evaluating the TOC content in the study *** of the sensitivity characteristics of TOC content to well logs reveals that the TOC content has good correlation with the separation degree of porosity *** a dimension reduction processing by the principal component analysis technology,the principal components are determined through correlation analysis of porosity *** results show that the TOC values obtained by the new method are in good agreement with that measured by core *** average absolute error of the new method is only 0.555,much less when compared with 1.222 of using traditional△logR *** proposed method can be used to produce more accurate TOC estimates,thus providing a reliable basis for source rock mapping.

关键词： Total organic carbon Principal component analysis Separation degree Source rocks Shale oil

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X型中心钢支撑混凝土框架地震反应特性

中南大学学报（自然科学版） 2015年第6期46卷 2299-2308页

作者：国静樊海涛烟台大学土木工程学院山东烟台264005

为了研究X型中心钢支撑钢筋混凝土框架结构体系地震反应特性,分别对5层、8层和12层钢筋混凝土框架和X型中心钢支撑钢筋混凝土框架模型结构的动力特性和弹性地震反应进行分析,探讨X型中心钢支撑对结构侧移刚度、自振周期、水平地震作用... 详细信息

为了研究X型中心钢支撑钢筋混凝土框架结构体系地震反应特性,分别对5层、8层和12层钢筋混凝土框架和X型中心钢支撑钢筋混凝土框架模型结构的动力特性和弹性地震反应进行分析,探讨X型中心钢支撑对结构侧移刚度、自振周期、水平地震作用下结构内力分布的影响。研究结果表明:在没有明显增大结构重力荷载的条件下,支撑提高了结构侧移刚度,降低了结构自振周期,减小了水平地震作用下结构侧移和层间侧移角;支撑分担了部分楼层剪力,改变了结构的内力分布特点,降低了结构构件的内力,为实现"多道设防"的抗震设计原则创造了有利条件;X型中心钢支撑对钢筋混凝土框架结构地震反应的影响随着层数的增大而有所降低,与普通框架相比,5层、8层和12层支撑框架最大层间位移角的降低幅度分别为36%,24%和20%。

关键词：钢筋混凝土框架 X型中心钢支撑地震反应特性反应谱法动力时程分析法

The Study on Teaching Pattern of Progressive Graduation Design in Civil Engineering Specialty

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The Study on Teaching Pattern of Progressive Graduation Desi...

Influences of chemical reactions on polysulfide reduction reaction process on promotor surface in Li-S batteries

2013年教育技术与管理科学国际会议

作者： haitao fan Jing Guo School of Civil Engineering Yantai University

Progressive graduate design is one of the graduate design teaching patterns that the graduate design results will be the deepening and improvement of the series of curriculum designs *** teaching pattern can improve efficiency and meet requirements of the design depth,and is advantageous to the grasp of the Graduation design content will be the deepening and perfect professional knowledge system and enhancement of the practice ability of students,and the enhancement of the teaching responsibility and the formation of the teacher groups.

关键词： graduation design teaching pattern teacher groups

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Nano Research 2024年第4期17卷 2712-2718页

作者： Yufeng Luo Zhenhan fang Zixin Hong Shaorong Duan haitao Liu Hengcai Wu Qunqing Li Yuegang Zhang Shoushan fan Wenhui Duan Jiaping Wang Tsinghua-Foxconn Nanotechnology Research Center Tsinghua UniversityBeijing 100084China Department of Physics Tsinghua UniversityBeijing 100084China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Frontier Science Center for Quantum Information Tsinghua UniversityBeijing 100084China

Polar promotors have been proven effective in catalyzing the polysulfide(PS)reduction reaction(PSRR)process in lithium-sulfur(Li-S)***,the promotor surface tends to be poisoned due to the accumulation of insoluble discharging products of lithium disulfide(Li_(2)S_(2))and lithium sulfide(Li_(2)S)during Li-S battery ***,we investigate the detailed PSRR mechanism on the surface of manganese sulfides(MnS)as a representative promoter by performing in-situ Raman mapping *** catalytic ability of MnS enables thorough electrochemical reduction of PSs to Li_(2)S_(2) and Li_(2)S on the MnS *** generated Li_(2)S_(2) and Li_(2)S then adsorb the dissolved PSs via chemical reactions among sulfur species during the subsequent PSRR *** phenomenon mitigates promotor poisoning and continuously improves the reversible ***,the assembled Li-S cell demonstrates excellent electrochemical performance after introducing a conductive interlayer containing a thin piece of carbon nanotube film and MnS promotors.

关键词： promotors polysulfides chemical reactions catalytic ability in-situ Raman measurements