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白肋烟中糖酯类化合物的分离与鉴定

质谱学报 2024年第3期45卷 375-385,I0003页

作者：袁凯龙朱俊臣谢越刘化兵金慧清孙翠荣张晓兵冯鸿儒潘远江浙江中烟工业有限责任公司浙江杭州310008 浙江大学药学院浙江省先进给药系统重点实验室浙江杭州310058 浙江大学化学系浙江杭州310027

烟草中糖酯类化合物是重要的致香前体物,对烟叶的品质具有重要影响。但目前还未见关于白肋烟烟叶中糖酯类化合物的分离分析研究。本实验利用高分辨液相色谱-串联质谱(LC-MSn)技术,从白肋烟叶提取物中共分离鉴定出4类蔗糖酯和2类葡萄糖酯... 详细信息

烟草中糖酯类化合物是重要的致香前体物,对烟叶的品质具有重要影响。但目前还未见关于白肋烟烟叶中糖酯类化合物的分离分析研究。本实验利用高分辨液相色谱-串联质谱(LC-MSn)技术,从白肋烟叶提取物中共分离鉴定出4类蔗糖酯和2类葡萄糖酯,每类均包含多种同系物。其中,4种蔗糖酯为首次发现,8种葡萄糖酯的结构鉴定在栽培烟草中为首次报道。本研究丰富了烟草中糖酯类化合物的种类,对烟草中不同类型蔗糖酯和葡萄糖酯的分析鉴定和代谢研究具有参考意义。

关键词：白肋烟蔗糖酯葡萄糖酯液相色谱-串联质谱(LC-MSn) 结构鉴定

Effects of Density-Dependent Quark Mass on Phase Diagram of Color-Flavor-Locked Quark Matter

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Communications in Theoretical Physics 2006年第4期45卷 691-696页

作者： zhang xiao-bing LI Xue-Qian Department of Physics Nankai University Tianjin 300071 China

Considering the density dependence of quark mass, we investigate the phase transition between the （unpaired） strange quark matter and the color-flavor-locked matter, which are supposed to be two candidates for the ground state of strongly interacting matter. We lind that if the current mass of strange quark m, is smmall, the strange quark matter remains stable unless the baryon density is very high. If m, is large, the phase transition from the strange quark matter to the color-flavor-locked matter in particular to its gapless phase is found to be different from the results predicted by previous works. A complicated phase diagram of three-flavor quark matter is presented, in which the color-flavor-locked phase region is suppressed for moderate densities.

关键词： strange quark matter color-flavor locked quark matter pairing

Influence of Relativistic Finite Volume Effect of Nucleons on the Dense Matter Properties

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Chinese Physics Letters 1998年第7期15卷 483-485页

作者： zhang xiao-bing zhang Qi-ren Department of Technical Physics Peking UniversityBeijing 100871

The influence of the relativistic finite volume effect of nucleons on the properties of dense nuclear matter is examined at finite temperature and it is found that the abnormal nuclear state can appear at sufficiently high ***,by using this methed the phase transition between hadronic matter and quark-gluon plasma is *** numerical results show that the value of nucleon radius is important for reproducing this phase transition correctly.

关键词： density finite transition

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金沙土遗址裂隙灌浆材料比选室内试验研究

科学技术与工程 2024年第7期24卷 2847-2855页

作者：岳磊王捷张小兵王逢睿周杰王瑞林中铁西北科学研究院有限公司兰州730000 国家文物局石窟保护技术重点科研基地兰州730000 甘肃省岩土文物保护工程技术研究中心兰州730000 甘肃省敦煌文物保护研究中心酒泉736200

为探究适用于金沙土遗址裂隙加固的灌浆材料,选取了烧料礓石、SH(改性聚乙烯醇)和无机矿物聚合物与金沙遗址试验土拌合制备了三种灌浆材料。通过室内试验,对各种灌浆材料结石体试样的基本物理性能、力学性能及耐久性能进行了详细分析。... 详细信息

为探究适用于金沙土遗址裂隙加固的灌浆材料,选取了烧料礓石、SH(改性聚乙烯醇)和无机矿物聚合物与金沙遗址试验土拌合制备了三种灌浆材料。通过室内试验,对各种灌浆材料结石体试样的基本物理性能、力学性能及耐久性能进行了详细分析。试验结果表明,无机矿物聚合物灌浆材料具有较低的收缩性,能够有效填充裂隙;同时,其较高的抗折和抗压强度为提升土遗址的力学稳定性提供了可靠保障;在研究的三种灌浆材料中,无机矿物聚合物灌浆材料展现出最佳的耐久性能。因此,建议在金沙土遗址的裂隙注浆加固工程中采用无机矿物聚合物灌浆材料,研究成果将为潮湿环境下土遗址裂隙灌浆材料的选择与应用提供有益的指导。

关键词：金沙遗址土遗址无机土加固剂灌浆材料

基于反向比例解析的近红外光谱定量模型快速构建方法

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分析测试学报 2024年第5期43卷 792-797页

作者：张晓兵徐志强钟永健朱宏福李峥张军詹映彭云发刘建国浙江中烟工业有限责任公司技术中心浙江杭州310024 上海创和亿电子科技发展有限公司上海200082

为解决光谱漂移问题,该研究设计了一种基于反向比例解析的近红外光谱定量模型方法。以烟叶近红外光谱和烟碱含量为研究对象,将数据划分为训练集和测试集。通过计算训练集光谱与测试集光谱的相关性并按照高低排序,选择前20%的光谱,运用... 详细信息

为解决光谱漂移问题,该研究设计了一种基于反向比例解析的近红外光谱定量模型方法。以烟叶近红外光谱和烟碱含量为研究对象,将数据划分为训练集和测试集。通过计算训练集光谱与测试集光谱的相关性并按照高低排序,选择前20%的光谱,运用约束规划的方法,计算测试集的拟合系数,得到测试集光谱的估计值。结果显示,使用反向比例解析法建立的模型的平均绝对误差为0.3466,预测标准偏差为0.4252,相关系数为0.7932,优于PLS模型。反向光谱比例解析可以有效解决光谱漂移问题,实现烟草中烟碱含量的准确预测,为烟碱的有效测量提供参考。

关键词：反向比例近红外光谱相关性拟合系数加权

Evaluation of Component Activity in Molten MnO-SiO_(2)-Al_(2)O_(3)-CaO System with Model SELF-SReM4

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Journal of Iron and Steel Research International 2000年第1期7卷 6-8页

作者： zhang xiao-bing JIANG Guo-chang XU Kuang-di Shanghai University

A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of *** application of SELF-SReM4 in C-Mn-Fe-Si system without the SiC formation has been introduced in previous ***’s application for molten slag of MnO-SiO2-Al2O3-CaO was introduced in this *** provide a basis for the prediction of the metal-slag equilibrium conditions.

关键词： sub-regular solution model component activity m olten slag MnO-SiO2-Al2O3-CaO

Levels and distributions of polychlorinated naphthalenes in sewage sludge of urban wastewater treatment plants

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Chinese Science Bulletin 2008年第4期53卷 508-513页

作者： GUO Li zhang bing xiao Ke zhang QingHua ZHENG MingHui State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences ChineseAcademy of Sciences Beijing 100085 China

Over seventy congeners of polychlorinated naphthalenes(PCNs) in sewage sludge of 8 urban waste-water treatment plants(WWTPs) in Beijing were analyzed by isotope dilution,and high resolution gas chromatography/high resolution mass spectrometry(HRGC/HRMS) *** total PCN concentrations determined in the samples range from 1.48 to 28.21 ng/g dw(dry weight) with TEQ concentrations of 0.11―2.45 pg/g *** levels were lower than those found in other *** and TrCNs were the most dominant homologues of *** similar congener profiles in all the samples suggest the similarity in certain *** from industrial input might be the most significant source of PCNs in the sludges in this study,and thermal processes such as waste incineration and coal combustion may be another source of the PCNs contamination.

关键词：污水污泥萘高分辨质谱法高分辨气相色谱分析城市污水处理厂

Optimization of Oscillation Model for Slab Continuous Casting Mould Based on Mould Friction Measurements in Plant Trial

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Journal of Iron and Steel Research International 2013年第1期20卷 13-20页

作者： WANG Xu-dong YAO Man zhang Li zhang xiao-bing CHEN Shao-hui School of Material Science and Engineering Dalian University of Technology Research Institute Baoshan Iron and Steel Co Ltd Jiangsu Sha-steel Group

Lubrication and friction between the mould and strand are strongly influenced by mould oscillation, and play an important role in slab quality and operating safety during continuous casting processes. Investigation of mould oscillation is therefore essential for getting a better online control of the mould processes. A feasible approach for the development and optimization of mould oscillation was put forward, which combined online measurement of mould friction, design of negative oscillating parameters and evaluation for powder consumption. Three different control models including sinusoidal and non-sinusoidal oscillation for mould oscillations were developed to investigate and evaluate the effects of oscillation on mould friction and powder lubrication. For the purpose of investigating mould friction between mould and strand, online measurement was carried out on a slab continuous caster equipped with a hydraulic oscillator. Also the comparison of the mould friction in sinusoidal and non-sinusoidal mould oscillation was made for subsequent analysis. The industrial experiment result shows that the combination of inverse control model and non-sinusoidal oscillation mode will contribute to the proper powder consumption, leading to a suitable effect of friction force on strand surface, especially for high speed continuous casting. The proposed method provides reliable basis for guiding and optimizing mould oscillation among control models, sinusoidal oscillation and non-sinusoidal oscillation.

关键词： continuous casting mould friction oscillation mode non-sinusoidal powder consumption

Effect of Nb Solute and NbC Precipitates on Dynamic or Static Recrystallization in Nb Steels

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Journal of Iron and Steel Research International 2012年第11期19卷 52-56页

作者： xiao Fu-ren CAO Ya-bin QIAO Gui-ying zhang xiao-bing LIAO Bo Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004HebeiChina School of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina Jiangsu Shagang Group Co Ltd Zhangjiagang215625JiangsuChina

Nb is often considered to be a powerful alloying element for controlling the recrystaUization process in mi- croalloyed high strength steels. However, Nb can be presented either as solute in solution, where it is thought to ex- hibit a strong solute drag effect, or as NbC precipitates, which are thought to be effective at pinning grain bounda- ries. Therefore, it is very important to quantitatively measure Nb in solution or in NbC precipitates. A quantitative analysis method of Nb in solution and in precipitates was proposed. The test procedure involved chemical dissolution, filtration and inductively coupled plasma atomic emission spectroscopic （ICP-AES） analysis. The amount of Nb in solution in Nb-microallyed steels under different treatment conditions was evaluated. The results show that the niobium and carbon contents in steels have a great effect on niobium dissolution kinetics. The solute Nb is more effective to retard dynamic recrystallization, while the NbC precipitates are more effective to inhibit static recrystaltization. The results may help to comprehend effect of Nb in steels, and provide some guides in the design of new high strength Nb-bearing steels.

关键词： Nh microalloyed steel solution precipitation quantitative analysis recrystallization