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高效液相色谱测定除脂生发片中丹皮酚、黄柏酮、5-O-甲基维斯阿米醇苷和胡薄荷酮

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化学分析计量 2024年第6期33卷 94-99页

作者：程莉穆晓冬河北中石油中心医院药学部河北廊坊065000

建立高效液相色谱波长切换法测定除脂生发片中丹皮酚、黄柏酮、5-O-甲基维斯阿米醇苷和胡薄荷酮成分含量。色谱柱为Agilent EclipsePlus C18(250 mm×4.6 mm,5μm);以乙腈(流动相A)-0.3%磷酸(流动相b)为流动相,梯度洗脱;柱温30℃;柱流量... 详细信息

建立高效液相色谱波长切换法测定除脂生发片中丹皮酚、黄柏酮、5-O-甲基维斯阿米醇苷和胡薄荷酮成分含量。色谱柱为Agilent EclipsePlus C18(250 mm×4.6 mm,5μm);以乙腈(流动相A)-0.3%磷酸(流动相b)为流动相,梯度洗脱;柱温30℃;柱流量1.0 mL/min;丹皮酚、黄柏酮、5-O-甲基维斯阿米醇苷和胡薄荷酮的检测波长分别为274、236、254和252 nm;进样体积:10μL,高效液相色谱-二极管阵列检测器定量检测。丹皮酚、黄柏酮、5-O-甲基维斯阿米醇苷和胡薄荷酮分别在质量浓度0.01996~1.996、0.5868~5.868、0.997~9.97、0.0998~9.98μg/mL内与其色谱峰面积呈线性关系,相关系数分别为0.9996、0.9980、0.9997和0.9999,平均回收率分别为100.92%、100.54%、101.14%、100.93%;测定结果的相对标准偏差均小于5.0%(n=6)。该方法具有样品处理简单、分析时间短、检测结果准确等优点,适用于除脂生发片制剂的质量控制。

关键词：高效液相色谱除脂生发片丹皮酚黄柏酮 5-O-甲基维斯阿米醇苷胡薄荷酮

离子液体表面活性剂改性凹凸棒石去除玉米赤霉烯酮

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硅酸盐学报 2024年第10期52卷 3170-3179页

作者：康玉茹牟斌朱永峰惠爱平王爱勤中国科学院兰州化学物理研究所甘肃省黏土矿物重点实验室兰州730000

玉米赤霉烯酮(ZEN)由于强生殖毒性、致癌等毒害作用,严重危害动物和人体健康,吸附法是去除ZEN的有效方法之一。采用咪唑类离子液体表面活性剂(C_nmimbr,n=12、14、16、18)改性凹凸棒石(APT)制备了ZEN吸附剂(C_nmimbr-APT)。通过Fourier... 详细信息

玉米赤霉烯酮(ZEN)由于强生殖毒性、致癌等毒害作用,严重危害动物和人体健康,吸附法是去除ZEN的有效方法之一。采用咪唑类离子液体表面活性剂(C_nmimbr,n=12、14、16、18)改性凹凸棒石(APT)制备了ZEN吸附剂(C_nmimbr-APT)。通过Fourier红外光谱(FT-IR)、X射线衍射(XRD)、氮气吸附-脱附分析等表征方法结合烧失量、吸湿率测定,探讨了C_nmimbr-APT的微观结构及表界面性质,系统考察了改性参数(C_nmimbr用量及碳链长度)和吸附条件(吸附剂用量、吸附时间、初始浓度、pH值、共存营养物质)对C_nmimbr-APT吸附性能的影响。结果表明:C_nmimbr改性过程未改变APT的晶体结构,改性后吸附剂的表面疏水性增强。吸附驱动力主要为C_nmimbr中碳链与ZEN分子间的疏水作用,吸附性能与C_nmimbr用量和碳链长度呈正相关。C_(16)mimbr-APT对ZEN的吸附过程符合准二级动力学模型和Langmuir等温模型,当C_(16)mimbr用量为5.0%(质量分数)时,C_(16)min br-APT对ZEN的最大吸附量为7.45 mg·g^(-1)。吸附体系的pH值及共存氨基酸、维生素和矿物质(L-赖氨酸、维生素b1、Ca^(2+)、Cu^(2+)、Fe^(3+)等)对ZEN吸附性能无显著影响。因此,C_nmimbr-APT在吸附去除ZEN方面具有潜在的应用价值。

关键词：凹凸棒石离子液体表面活性剂玉米赤霉烯酮吸附

一种用于探冰雷达的高增益Vivaldi天线

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上海电力大学学报 2024年第3期40卷 274-278,292页

作者：曹小兵窦银科寇立伟左广宇太原理工大学电气与动力工程学院山西太原030024 山西省能源互联网研究院极地与极端环境能源装备设计与控制团队山西太原030032

介绍了一种用于S波段(2~4 GHz)探冰雷达的高增益Vivaldi天线。天线选择介电常数3.48的ROC4350b为介质板材料,采用微带馈电线转槽线的耦合结构进行馈电,并在辐射臂两侧加载两段指数型开槽提升整体增益,在渐变槽线中间加载指数型引向器进... 详细信息

介绍了一种用于S波段(2~4 GHz)探冰雷达的高增益Vivaldi天线。天线选择介电常数3.48的ROC4350b为介质板材料,采用微带馈电线转槽线的耦合结构进行馈电,并在辐射臂两侧加载两段指数型开槽提升整体增益,在渐变槽线中间加载指数型引向器进一步提升天线辐射性能。仿真优化后天线总体尺寸为113.6 mm×85.0 mm×1.52 mm。仿真结果表明,天线在S波段内回波损耗S11b,天线增益整体在5.39 db以上,最高达到了9.6 db,且增益曲线平滑,实测结果与仿真结果较为吻合。

关键词： Vivaldi天线带宽指数型开槽指数型引向器

Social acceptance for commercialization of genetically modified food animals

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National Science Review 2021年第8期8卷 136-137页

作者： Ziyao Fan Yulian mu Tad Sonstegard Xiaomei Zhai Kui Li Perry b.Hackett Zuoyan Zhu Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural Sciences State Key Laboratory of Animal Nutrition Institute of Animal ScienceChinese Academy of Agricultural Sciences Center for bioethics Chinese Academy of Medical Sciences and Peking Union Medical College School of Population Medicine and Public Health Peking Union Medical College Center for Genome Engineering Department of Genetics Cell Biology and Development University of Minnesota State Key Laboratory of Freshwater Ecology and biotechnology Institute of Hydrobiology Chinese Academy of Sciences

Since late 2020, China and the United States, the world’s two largest economies,have embarked on regulatory reforms to boost the regulatory development of genetically modified food animals(GMFAs). The Ministry of Agriculture and Rural Affairs of the People’s Republic of China issued a circular to encourage original innovation of agriculturally important,

关键词： CATTLE

Investigation of kinetics in bioaugmentation of crude oil via high-throughput sequencing: Enzymatic activities, bacterial community composition and functions

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Petroleum Science 2022年第4期19卷 1905-1914页

作者： Yong-Rui Pi mu-Tai bao School of Ocean Yantai UniversityYantai264005China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education/Institute for Advanced Ocean StudyOcean University of China Qingdao266100China

The enzymes and the characteristics of the community of the petroleum-degrading bacteria play a crucial role in the crude oil biodegradation. The prediction of kinetics of the key groups of hydrocarbons in crude oil was important to evaluate the bioremediation speed and constant. Most of the n-alkanes(C9-C29) were degraded in 25 days, and the average degradation rates of C_(18)~C_(27) higher than 100 μg g^(-1) d^(-1).The hopanes, such as H_(30), had a biodegradation rate more than 10 μg g^(-1) d^(-1). The related enzymes activities changed along with the crude oil biodegradation, especially dehydrogenase. The 16 S rRNA gene amplicon sequencing revealed that Proteobacteria, Firmcutes, bacteroidetes, Actinobacteria, Acidobacteria were the main petroleum hydrocarbon degraders during the crude oil biodegradation, and the top two highest relative abundance of the genera were Alcaligenes and Acinetobacter. Acinetobacter presented positive correlation to biodegradation of n-alkanes and PAHs. based on COG analysis, the largest group involved in the general function was amino acid transport and metabolism. The functional categories of bacterial communities were mainly focused on the carbohydrate and amino acid metabolism, xenobiotics biodegradation and metabolism, membrane transport, and so on. Overall, these findings highlight the potential guideline for more adequate monitoring of microbial degradation of crude oil.

关键词： Crude oil bioaugmentation Kinetics Enzyme activities Microbial functions

Decorating ketjen black with ultra-small Mo_(2)C nanoparticles to enhance polysulfides chemisorption and redox kinetics for lithium-sulfur batteries

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Journal of Energy Chemistry 2020年第12期29卷 207-215页

作者： Nan Jiang guangyu Jiang Dechao Niu Jiayi Mao Meiwan Chen Kaiyuan Li Yongsheng Li Lab of Low-Dimensional Materials Chemistry Key Laboratory for Ultrafine Materials of Ministry of Education.School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The low sulfur utilization and fast capacity fading resulting from the sluggish redox reaction and abominable polysulfides shuttle greatly hinder the practical applications of lithium-sulfur(Li-S) ***, we develop a facile "in-situ growth" method to decorate ultra-small Mo2 C nanoparticles(USMo2 C) on the surface of Ketjen black(Kb) to functionalize the commercial polypropylene(PP) separators,which can accelerate the redox kinetics of lithium polysulfides conversion and effectively increase the utilization of sulfur for Li-S batteries. Importantly, the US-Mo2 C nanoparticles have abundant sites for chemical adsorption towards polysulfides and the conductive carbon networks of Kb have cross-linked pore channels, which can promote electron transport and provide physical barrier and volume expansion space for polysulfides. Due to the combined effects of the US-Mo2 C and Kb, Li-S cells employing the multifunctional PP separators modified with Kb/US-Mo2 C composite(Kb/US-Mo2 C@PP) exhibit a high specific capacity(1212.8 mAh g^(-1) at 0.2 C), and maintain a reversible capacity of 1053.3 m Ah g^(-1) after 100 *** importantly, the Kb/US-Mo2 C@PP cells with higher sulfur mass loading of 4.9 mg cm^(-2) have superb areal capacity of 2.3 mAh cm^(-2). This work offers a novel and promising perspective for high-performance Li-S batteries from both the shuttle effect and the complex polysulfides conversion.

关键词： in-situ growth Ultra-small Mo_(2)C Catalytic effect Chemisorption multifunctional separator Lithium-sulfur batteries

NUMERICAL SOLUTION OF THE THREE-DIMENSIONAL ELASTOHYDRODYNAMIC LUbRICATION FOR HEAVILY-LOADED FINITE JOURNAL bEARINGS

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Journal of Hydrodynamics 1992年第4期4卷 78-87页

作者： Sun, mu Lin, Xiaohui Navigatoin Engineering Coll of Nanjing Nanjing China

Elastohydrodynamic lubrication theory is combination of classical hydrodynamic lubrication and elastic theory. A coupling of finite element and boundary element method was applied to the analysis of 3-D elastohydro-dynamic lubrication for heavily-loaded finite journal bearings. In order to overcome difficulties of convergence at high eccentricity ratios, an iterative scheme was provided in this paper. The scheme called weighted average method was successfully carried out in the iterative procedures of a set of nonlinear equations that was constituted by a 2-D Reynolds' equation, a viscosity-pressure equation as well as 3-D elasticity equations. The analysis yields performances parameters and minimum film thickness of the finite journal bearings under heavy loading.

关键词： boundary element method Elastohydrodynamics Finite element method Journal bearings Three dimensional

Description of spectrum and electromagnetic transitions in ^(94)Mo through the proton-neutron interacting boson model

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Science China(Physics,Mechanics & Astronomy) 2018年第1期61卷 37-43页

作者： ChengFu mu DaLi Zhang Department of Physics Huzhou University

We investigated the properties of low-lying states in ^(94)Mo within the framework of the proton-neutron interacting boson model(IbM-2), with special focus on the characteristics of mixed-symmetry states. We calculated level energies and M1 and E2 transition strengths. The IbM-2 results agree with the available quantitative and qualitative experimental data on ^(94)Mo. The properties of mixed-symmetry states can be well described by IbM-2 given that the energy of the d proton boson is different from that of the neutron boson, especially for the transition of b(M1, 4_2^+→ 4_1^+).

关键词： 94Mo mixed-symmetry states M1 and E2 transition strengths IbM-2

Description of mixed symmetry states in 96Ru using IbM-2

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 32-39页

作者： DaLi ZHANG ChengFu mu Department of Physics Huzhou University Huzhou 313000 China

We have investigated the properties of low-tyiag states iu 96Ru within the framework of the neutron-proton interacting boson model （IbM-2）, with special attention paid to the characteristics of the mixed symmetry states. by considering the relative energy of d proton boson to be different from that of neutron boson, the level energies and M1, E2 transition strengths have been calculated. The IbM-2 calculation is consistent with the experimental data of 96Ru both quantitatively and qualitatively. Particularly, the strong M1 transition between the 42^＋ and 41^＋ states has been reproduced nicely. The calculated results show that the M1 transition strength of b（M1,42^＋ → 41^＋） in 96Ru carl be described successfully by the IbM-2.

关键词： 96Ru mixed-symmetry M1 transition strengths IbM-2