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Photocatalytic Oxidative Desulfurization of Dibenzothiophene on TiO2 Modified Bimodal Mesoporous Silica

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China Petroleum Processing & Petrochemical Technology 2017年第3期19卷 59-67页

作者： xu meizhen Yang Lina Li Jian School of Petrochemical Engineering Liaoning Shihua UniversityFushun 113001

By using the bimodal mesoporous silica(BMMS) as the carrier and butyl titanate as the titanium source, the TiO_2/BMMS catalyst was prepared. The samples were characterized by XRD, XRF, N_2 adsorption and desorption, FTIR, UVvis,SEM, EDS, and TEM techniques. The test results showed that TiO_2 was amorphous, the TiO_2/BMMS catalyst had an ordered bimodal mesoporous structure, and the chemical interaction existed between BMMS and TiO_2. Since the TiO_2/BMMS had a lower band gap, its photocatalytic activity was better than TiO_2. Under UV irradiation a one-pot PODS system was set up, using TiO_2/BMMS as the catalyst, H_2O_2 as the oxidant, and methanol as the solvent. The TiO_2/BMMS catalyst showed better photocatalytic activity than the mono-modal mesoporous TiO_2/SBA-15 catalyst, and the desulfurization rate of dibenzothiophene(DBT) over TiO_2/BMMS catalyst could reach 99._2%. The TiO_2/BMMS catalyst also had so good stability that the desulfurization rate of DBT did not drop apparently after 8 cycles of reusing, and could still be close to 90%.

关键词： bimodal mesoporous silica amorphous TiO2 photocatalytic activity UV irradiation dibenzothiophene

Synthesis of Bimodal Mesoporous TiO_(2)-PTA/BMMS and Its Enhanced Performance in the Photocatalytic Oxidative Desulfurization

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China Petroleum Processing & Petrochemical Technology 2021年第3期23卷 58-68页

作者： Yang Lina Zhang Xi Cui Licheng xu meizhen Li Jian School of Petrochemical Engineering Liaoning Petrochemical UniversityLiaoning 113001

With the bimodal mesoporous silica(BMMS)acting as the support and the composite of TiO2 with phosphotungstic acid(PTA)functioning as the active constituent,TiO_(2)-PTA/BMMS was synthesized by the two-step impregnation *** catalyst was applied in the photocatalytic oxidative desulfurization(PODS)process,with dibenzothiophene serving as the model sulfur *** proceeds in one pot,in which H_(2)O_(2) acts as the oxidant and methanol plays the role of the ***_(2)-PTA/BMMS was characterized by XRD,N_(2) adsorption and desorption,XRF,FTIR,UV-vis,SEM,EDS and TEM *** showed that the introduction of PTA contributes higher order,higher surface area and pore volume to the bimodal mesoporous *** TiO_(2)-PTA/BMMS used as the catalyst under the UV irradiation,the desulfurization rate can reach 99.6%.This result is obviously higher than that achieved by TiO_(2)/*** catalyst also has no significant drop in catalytic activity after eight runs of *** such catalytic system,the synergistic effects of this photocatalytic oxidation and the extraction with the methanol serving as the solvent played an indispensable role.

关键词： phosphotungstic acid bimodal mesoporous silica titanium dioxide photocatalytic desulfurization UV irradiation dibenzothiophene

Induction of the apoptosis, degranulation and IL-13 production of human basophils by butyrate and propionate via suppression of histone deacetylation

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Induction of the apoptosis, degranulation and IL-13 producti...

第十四届全国免疫学学术大会

作者： Yanbiao Shi meizhen xu Shuai Pan Hui Wang Jiangsu Key Laboratory of Immunity and Metabolism Department of Pathogenic Biology and ImmunologyXuzhou Medical University

Background: Allergic diseases are orchestrated by dysregulated Th2-type immune responses involving multiple immune effector cells. Basophils are one of the key effector cells in mediating allergic immune responses through releasing cytokines and mediators e.g. IL-4, IL-13 and histamine. Short chain fatty acids(SCFAs) produced by commensal intestinal microbiota via fermentation of indigestible dietary fibers are reported to suppress allergic immune reactions by targeting mast cells, eosinophils and type 2 innate lymphoid cells(ILC2). However, the role of SCFAs on basophils are not known yet. In this study, we aimed to elucidate the function of SCFAs on human ***: Human basophils were purified from healthy donors by FACS sorting. The expression of surface receptors and the apoptosis were analyzed by flow cytometric analysis. The cytokines IL-4 and IL-13 and histamine release were measured by ***: Human basophils express SCFAs receptor GPR41, which was enhanced by IL-3 rather than other established modulators e.g. anti-IgE, fMLP or C5a. Acetate but not propionate and butyrate induced calcium influx via GPR41. However, SCFA propionate and butyrate rather than acetate induced the apoptosis of basophils. In vitro cytokine release assay showed that propionate and butyrate suppressed the expression of IL-4 while acetate, propionate and butyrate enhanced the expression of IL-13. Moreover, propionate and butyrate enhanced the histamine release associated with increased expression of the basophil degranulation marker ***: Our findings demonstrate that a complicated role of SCFAs in mediating the biology of basophils. The effects of SCFAs in regulating basophils-associated allergic disorders need to be further justified.

关键词： basophil Short chain fatty acids histone deacetylation

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中小学智育主要问题的调查与分析

当代教育科学 2006年第1期 30-33,36页

作者：徐美贞中央教育科学研究所学校教育研究部

经过几年的实验与探索，以课程改革为标志的智育已经取得了一些比较明显的成效。但是随着课程改革实验的不断深入和全面推进，新课程实施过程中的一些问题也逐渐显现。同时，我们也注意到，在智育方面存在着地区、城乡、学段方面的差异... 详细信息

经过几年的实验与探索，以课程改革为标志的智育已经取得了一些比较明显的成效。但是随着课程改革实验的不断深入和全面推进，新课程实施过程中的一些问题也逐渐显现。同时，我们也注意到，在智育方面存在着地区、城乡、学段方面的差异，呈现出发展不平衡的现象。为了了解我国智育中主要问题的现状，为今后的学校实践活动提供更好的服务，同时为教育决策部门制定更加符合实情的新课程政策提供依据，我们于2004年开展了本次调查研究工作。

关键词：调查与分析智育中小学课程改革实验调查研究工作发展不平衡课程实施实践活动课程政策决策部门

一类内部点条件含有谱参数的二阶微分算子的特征值

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数学物理学报（A辑） 2024年第4期44卷 815-828页

作者：刘薇许美珍内蒙古工业大学理学院呼和浩特010051

该文主要讨论了一类内部点条件含有谱参数的二阶微分算子的自伴性和特征值的依赖性.首先,在适当的Hilbert空间中定义一个与问题相关的线性算子T,将所要研究的问题转化为对此空间中算子T的研究,并根据自伴算子的定义证明了算子T是自伴的... 详细信息

该文主要讨论了一类内部点条件含有谱参数的二阶微分算子的自伴性和特征值的依赖性.首先,在适当的Hilbert空间中定义一个与问题相关的线性算子T,将所要研究的问题转化为对此空间中算子T的研究,并根据自伴算子的定义证明了算子T是自伴的.另外,在自伴的基础上,证明了特征值不仅连续依赖而且可微依赖于问题的各个参数,并给出相应的微分表达式.同时,还讨论了特征值关于问题部分参数的单调性.

关键词：内部点条件谱参数自伴性特征值的依赖性特征值的单调性

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一类具有转移条件高阶微分算子的J-自伴性

数学进展 2022年第1期51卷 93-102页

作者：李骥许美珍内蒙古工业大学理学院内蒙古呼和浩特010051

本文研究了一类具有转移条件的高阶复系数微分算子的J-自伴性,利用J-对称微分算式的拉格朗日双线性型、J-自伴算子的定义及矩阵表示的方法,证明了这类微分算子是J-自伴的,且对应于不同特征值的特征向量和特征子空间都是C-正交的.

关键词：高阶微分算子转移条件 J-自伴 C-正交

Regulation of T lymphocyte development and homeostasis by Aurora-A

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Regulation of T lymphocyte development and homeostasis by Au...

边界条件含有特征参数的四阶微分算子的自伴性和特征值的依赖性

第十四届全国免疫学学术大会

作者： Sijia Gao Shuai Pan Yanbiao Shi meizhen xu Ruixue Bai Jinfeng Ren Hui Wang xuzhou Medical University

The serine/threonine kinase Aurora-A plays a crucial role in controlling cellular division and has been implicated to contribute to *** cancer clinical trials have reported suppression of peripheral lymphocyte counts by treatment with Aurora-A inhibitor,indicating a possible role of Aurora-A in regulating lymphocytes *** lab has recently reported that ablation of Aurka inhibits the development and homeostasis of B *** it has been shown that Aurora-A regulates T lymphocyte activation by controlling LCK phosphorylation,its role in regulating the biology ofT lymphocytes remains to be further ***,we in the present study generated T cell specific Aurka knockout mice,namely LckAurka mice and CD4Aurka mice,which had Aurka deleted at the stage of double negative(DN) 3 and double positive(DP),*** of Aurka in LckAurka mice led to a significant reduction of DN3 and DN4 thymocytes in the thymus while no change of thymocyte development in CD4Aurka *** analysis revealed reduced CD4and CD8T lymphocytes in secondary lymphoid organs from both LckAurka and CD4Aurka ***,this reduction was associated with loss of naive CD4and CD8T *** addition,increased apoptosis of DN thymocytes and naive CD4T cells from LckAurka mice was observed upon in vitro stimulation with *** results indicate that Aurora-A might regulate T cell development at the DN stages and T cell homeostasis through acting downstream of IL-7 signaling pathway.

关键词： Aurora-A lymphocyte development peripheral homeostasis

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数学物理学报（A辑） 2022年第3期42卷 671-693页

作者：闫文文许美珍内蒙古工业大学理学院呼和浩特010051

该文考虑了一类边界条件一端含有特征参数且具有转移条件的四阶微分算子的自共轭性及特征值的依赖性.通过在适当的Hilbert空间上定义一个与问题相关的线性算子T,将上述问题的研究转化为对此空间中算子的研究,并证明算子T是自共轭的.另外... 详细信息

该文考虑了一类边界条件一端含有特征参数且具有转移条件的四阶微分算子的自共轭性及特征值的依赖性.通过在适当的Hilbert空间上定义一个与问题相关的线性算子T,将上述问题的研究转化为对此空间中算子的研究,并证明算子T是自共轭的.另外,在算子T自伴的基础上证明特征值不仅连续依赖而且可微依赖于问题的各个参数,并给出相应的微分表达式.特别地,给出特征值关于特征参数依赖的边界条件系数矩阵的Fréchet导数及关于内部不连续点c左右两侧的一阶导数.

关键词：四阶微分算子转移条件自共轭性特征值的依赖性 Fréchet导数

隐式曲面多孔结构压缩性能与流体压降性能研究

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机械工程学报 2024年第18期60卷 394-406页

作者：张明康师文庆徐梅珍王迪陈杰广东海洋大学机械与能源工程学院阳江529500 华南理工大学阳江研究院阳江529500 广东海洋大学材料科学与工程学院阳江529500 广东海洋大学食品科学与工程学院阳江529500 华南理工大学机械与汽车工程学院广州510641

传统金属过滤器的制造工序复杂、开发周期长,对于一些特殊过滤装置难以实现快速迭代设计和制造。压降性能是过滤器的重要评价指标之一,而过滤器结构在流体压力较大时,也需要同时考虑其力学性能。为解决上述问题,基于隐式曲面函数夹断优... 详细信息

传统金属过滤器的制造工序复杂、开发周期长,对于一些特殊过滤装置难以实现快速迭代设计和制造。压降性能是过滤器的重要评价指标之一,而过滤器结构在流体压力较大时,也需要同时考虑其力学性能。为解决上述问题,基于隐式曲面函数夹断优化函数,设计并通过激光选区熔化成形技术制备四种经典隐式曲面多孔结构过滤器,研究对比其压缩性能和压降性能。研究结果表明,Gyroid、Diamond和IWP三种隐式曲面多孔结构的压缩曲线属于弯曲主导型结构变形方式,Primitive多孔结构的压缩曲线属于拉伸主导型结构变形方式,且Primitive结构具有最高的压缩弹性模量和屈服强度,同时拟合四种隐式曲面多孔结构的Gibson-Ashby修正预测模型。利用优化后的隐式曲面结构函数,设计多孔过滤器,其压降分析结果表明,Primitive的压降值最低,流体阻力最小,因此Primitive结构可作为过滤器最优的设计单元体类型。分析隐式曲面多孔过滤器结构的力学性能和压降性能,揭示其压降变化机理,为新型过滤器结构设计提供参考。

关键词：多孔结构增材制造隐式曲面力学性能过滤器