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高速逆流色谱法一次性分离制备藏药蓝玉簪龙胆中的三个化合物

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西南民族大学学报（自然科学版） 2016年第6期42卷 660-664页

作者：李姗赵野刘圆张志锋西南民族大学药学院西南民族大学青藏高原研究院四川成都610041

目的:通过高速逆流色谱法(HSCCC)从藏药材蓝玉簪龙胆中分离制备得到三个高纯度化合物.方法:选择乙酸乙酯-正丁醇-水(4:0.5:5,v/v/v)为二相溶剂系统,上下两相分别作为固定相、流动相,主机转速设置为900 r/min,流动相溶剂流速为2.m L/min... 详细信息

目的:通过高速逆流色谱法(HSCCC)从藏药材蓝玉簪龙胆中分离制备得到三个高纯度化合物.方法:选择乙酸乙酯-正丁醇-水(4:0.5:5,v/v/v)为二相溶剂系统,上下两相分别作为固定相、流动相,主机转速设置为900 r/min,流动相溶剂流速为2.m L/min,紫外检测波长为2.4 nm,柱温为2.℃.所采集的组分减压浓缩后烘干得到龙胆苦苷、异荭草素、异牡荆苷,应用ESI-MS/MS分析鉴定,并用HPLC测定其质量分数.结果:在2.0 min内可一步纯化150 mg藏药材蓝玉簪龙胆水粗提物中的龙胆苦苷、异荭草素、异牡荆苷,三者完全分离,纯度分别达到98.2.、94.5%、96.0%.结论:利用高速逆流色谱法可快速、简单、高效地富集蓝玉簪龙胆中龙胆苦苷、异荭草素、异牡荆苷三种化合物.

关键词：高速逆流色谱蓝玉簪龙胆龙胆苦苷异荭草素异牡荆苷

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转基因作物对土壤无脊椎动物的影响

生态学杂志 2016年第10期35卷 2838-2844页

作者：郭佳惠孔云李刚赵建宁杨殿林闫凤鸣修伟明农业部产地环境质量重点实验室农业部环境保护科研监测所天津300191 河南农业大学植物保护学院郑州450002 沈阳农业大学植物保护学院沈阳110866

随着生物技术的快速发展,越来越多的转基因作物被引入农业生态系统,继而引发转基因作物对土壤生态系统带来影响的担忧。土壤无脊椎动物作为食物链中的分解者,是土壤生态系统的重要组成成分,其数量和多样性直接与土壤的健康和质量相关。... 详细信息

随着生物技术的快速发展,越来越多的转基因作物被引入农业生态系统,继而引发转基因作物对土壤生态系统带来影响的担忧。土壤无脊椎动物作为食物链中的分解者,是土壤生态系统的重要组成成分,其数量和多样性直接与土壤的健康和质量相关。土壤无脊椎动物作为土壤质量的重要指标,已成为转基因作物环境安全性评价的重要内容之一。本文在概述近些年国内外关于转基因作物外源表达产物在土壤中的残留动态的检测结果的基础上,综述关于棉花、玉米、水稻、油菜等转基因作物对线虫、跳虫、螨类和蚯蚓等代表性土壤无脊椎动物影响的最新研究进展。总体来说,转基因作物对土壤无脊椎动物的群落多样性没有明显不利影响,但个别对环境变化特别敏感的类群,在数量或组成上有所不同。由于调查方法和作物种类、土壤类型等因素的不统一,不同的研究结果无法进行比较,因此,建议尽快建立转基因作物对土壤无脊椎动物影响的评价方法和标准,以便为转基因作物的环境影响评价提供客观可靠的评价结果,推动我国的转基因作物研发和商业化推广,同时最大限度地降低转基因作物对环境的不利影响。

关键词：转基因作物土壤无脊椎动物土壤生态系统环境风险评价

Precisely modulating covalent and coordination bonds in the porous network for highly selective metal ion extraction

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Science China Chemistry 2024年第4期67卷 1039-1040页

作者： Jie Li Xiao feng Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials Key Laboratory of Cluster ScienceMinistry of EducationAdvanced Technology Research Institute(Jinan)Frontiers Science Center for High Energy MaterialSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Scandium(Sc)is recognized as a“strategic”and“critical”element by several countries,including the *** Russia,owing to its wide range of applications in high-tech fields such as superconductivity,alloys,lasers,nucle... 详细信息

关键词： alloys coordination network

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052.aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang Li Qing Yu feng-feng Chen Jia-wen He Hong-mei Yang Meng-nie Li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052.aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052.aluminum alloy was studied by adding 0%,0.05%,0.2.,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052.alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052.aluminum alloy Al3Fe phase mechanical properties grain boundary

Quantifying quantum entanglement via machine learning models

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Communications in Theoretical Physics 2024年第7期76卷 52-56页

作者： Changchun feng Lin Chen LMIB(Beihang University) Ministry of EducationBeijing 100191China School of Mathematical Sciences Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 00191China

Quantifying entanglement measures for quantum states with unknown density matrices is a challenging *** learning offers a new perspective to address this *** training machine learning models using experimentally measurable data,we can predict the target entanglement *** this study,we compare various machine learning models and find that the linear regression and stack models perform better than *** investigate the model's impact on quantum states across different dimensions and find that higher-dimensional quantum states yield better ***,we investigate which measurable data has better predictive power for target entanglement *** correlation analysis and principal component analysis,we demonstrate that quantum moments exhibit a stronger correlation with coherent information among these data features.

关键词： quantum information entanglement predict machine learning coherence

Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws

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Communications on Applied Mathematics and Computation 2024年第1期6卷 605-624页

作者： feng Zheng Jianxian Qiu College of Mathematics and Statistics Fujian Normal UniversityFuzhou350117FujianChina School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling&High-Performance Scientific Computing Xiamen UniversityXiamen361005FujianChina

In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation *** can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary ***,it avoids complicated least square procedure when we implement the genuine two dimensional(2.)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO *** numerical tests are performed to verify the high resolution and high accuracy of the scheme.

关键词： Finite volume Dimension by dimension HWENO Hyperbolic conservation laws

A dual-function selection system enables positive selection of multigene CRISPR mutants and negative selection of Cas9-free progeny in Arabidopsis

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aBIOTECH 2024年第2期5卷 140-150页

作者： feng-Zhu Wang Ying Bao Zhenxiang Li Xiangyu Xiong Jian-feng Li State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

The CRISPR/Cas9 technology revolutionizes targeted gene knockout in diverse organisms including ***,screening edited alleles,particularly those with multiplex editing,from herbicide-or antibiotic-resistant transgenic plants and segregating out the Cas9 transgene represent two laborious *** solutions to facilitate these processes rely on different selection ***,by taking advantage of the opposite functions of a D-amino acid oxidase(DAO)in detoxifying D-serine and in metabolizing non-toxic D-valine to a cytotoxic product,we develop a DAO-based selection system that simultaneously enables the enrichment of multigene edited alleles and elimination of Cas9-containing progeny in Arabidopsis *** five DAOs tested in Escherichia coli,the one encoded by Trigonopsis variabilis(TvDAO)could confer slightly stronger D-serine resistance than other *** expression of TvDAO in Arabidopsis allowed a clear distinction between transgenic and nontransgenic plants in both D-serine-conditioned positive selection and D-valine-conditioned negative *** a proof of concept,we combined CRISPR-induced single-strand annealing repair of a dead TvDAO with D-serine-based positive selection to help identify transgenic plants with multiplex editing,where D-serine-resistant plants exhibited considerably higher co-editing frequencies at three endogenous target genes than those selected by ***,D-valine-based negative selection successfully removed Cas9 and TvDAO transgenes from the survival offspring carrying inherited ***,this work provides a novel strategy to ease CRISPR mutant identification and Cas9 transgene elimination using a single selection marker,which promises more efficient and simplified multiplex CRISPR editing in plants.

关键词： CRISPR Genome editing D-amino acid oxidase Cas9-free Selection marker

Honokiol Prevents Intestinal Barrier Dysfunction in Mice with Severe Acute Pancreatitis and Inhibits JAK/STAT1 Pathway and Acetylation of HMGB1

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Chinese Journal of Integrative Medicine 2024年第6期30卷 534-542页

作者： LI Jie CHEN Ya-feng GAO Lei LI Yi-jie feng Dian-xu Department of General Surgery Putuo HospitalShanghai University of Traditional Chinese MedicineShanghai200062China

Objective To investigate the effect of honokiol(HON)and the role of high-mobility group protein B1(HMGB1)on the pathogenesis of severe acute pancreatitis(SAP).Methods Thirty mice were numbered according to weight,and randomly divided into 5 groups using a random number table,including control,SAP,SAP and normal saline(SAP+NS),SAP and ethyl pyruvate(SAP+EP),or SAP+HON groups,6 mice in each *** of pancreas,intestine,and blood were collected 12.h after SAP model induction for examination of pathologic changes,immune function alterations by enzyme linked immunosorbent assay(ELISA),and Western *** vitro experiments,macrophages were divided into 5 groups,the control,lipopolysaccharide(LPS),LPS+DMSO(DMSO),LPS+anti-HMGB1 monoclonal antibody(mAb),and LPS+HON *** tight connection level was determined by transmission electron microscopy and fluorescein *** location and acetylation of HMGB1 were measured by Western ***,pyridone 6 and silencing signal transducer and activator of the transcription 1(siSTAT1)combined with honokiol were added to determine whether the Janus kinase(JAK)/STAT1 participated in the regulation of honokiol on *** protein expression levels of HMGB1,JAK,and STAT1 were detected using Western *** Mice with SAP had inflammatory injury in the pancreas,bleeding of intestinal tissues,and cells with disrupted *** in the SAP+HON group had significantly fewer pathological *** with SAP also had significant increases in the serum levels of amylase,lipase,HMGB1,tumor necrosis factor-α,interleukin-6,diamine oxidase,endotoxin-1,and *** in the SAP+HON group did not show these abnormalities(P2.cells indicated that LPS increased the levels of occludin and claudin-1 as well as tight junction permeability,decreased the levels of junctional adhesion molecule C,and elevated intercellular permeability(P<0.01).HON treatment blocked these *** of

关键词： severe acute pancreatitis intestinal barrier dysfunction honokiol high-mobility group protein B1 Januskinase signal transducerand activatorof transcription1

Enhanced High-Temperature Energy Storage Performance of All-Organic Composite Dielectric via Constructing Fiber-Re in forced Structure

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Energy & Environmental Materials 2024年第2期7卷 299-307页

作者： Mengjia feng Yu feng Changhai Zhang Tiandong Zhang Xu Tong Qiang Gao Qingguo Chen Qingguo Chi Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China School of Electrical and Electronic Engineering Harbin University of Science and TechnologyHarbin 150080China

Optimizing the high-temperature energy storage characteristics of energy storage dielectrics is of great significance for the development of pulsed power devices and power control *** a polymer with a higher glass transition temperature(T_(g))as the matrix is one of the effective ways to increase the upper limit of the polymer operating ***,current high-T_(g)polymers have limitations,and it is difficult to meet the demand for high-temperature energy storage dielectrics with only one *** example,polyetherimide has high-energy storage efficiency,but low breakdown strength at high *** has high corona resistance,but low high-temperature energy storage *** this work,combining the advantages of two polymer,a novel high-T_(g)polymer fiber-reinforced microstructure is *** is designed as extremely fine fibers distributed in the composite dielectric,which will facilitate the reduction of high-temperature conductivity loss for *** the same time,due to the high-temperature resistance and corona resistance of polyimide,the high-temperature breakdown strength of the composite dielectric is *** the polyimide content with the best high-temperature energy storage characteristics is determined,molecular semiconductors(ITIC)are blended into the polyimide fibers to further improve the high-temperature ***,excellent high-temperature energy storage properties are *** 0.2. vol%ITIC-polyimide/polyetherimide composite exhibits high-energy density and high discharge efficiency at 150℃(2.9 J cm^(-3),90%)and 180℃(2.16 J cm^(-3),90%).This work provides a scalable design idea for high-performance all-organic high-temperature energy storage dielectrics.

关键词： all-organic energy storage density high-temperature high-temperature breakdown strength