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胶原蛋白及多酚：新关系及新成果（第一部分：新鞣制过程中类黄酮地反应）

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北京皮革（中外皮革信息版）（中） 2008年第5期 95-101页

作者： A．D．covington T．H．Lilley L．song c．s．evans 王亚娟（编译）不详四川成都四川大学轻纺与食品学院 610065

植物鞣剂的收敛性会影响鞣制效果，从而影响其在现代鞣制中作为有机鞣剂的发展。非鞣剂的存在避免了由于多酚的强反应性而导致鞣剂不能充分渗透到皮内的问题，而非鞣剂来自于自然产物，如绿茶或由鞣剂降解为非鞣剂。而无论是鞣质还是非... 详细信息

植物鞣剂的收敛性会影响鞣制效果，从而影响其在现代鞣制中作为有机鞣剂的发展。非鞣剂的存在避免了由于多酚的强反应性而导致鞣剂不能充分渗透到皮内的问题，而非鞣剂来自于自然产物，如绿茶或由鞣剂降解为非鞣剂。而无论是鞣质还是非鞣质在结合鞣时都可以与醛类物质发生结合，从而使胶原的湿热稳定性得以提高。原翠雀定以及原剌槐青定的使用在该篇文章中被提及，他们的共同特点就是含有连苯三酚B环。同时非鞣质的用途也为现代有机鞣制提供了特定路径。

关键词：反应性鞣制多酚胶原类黄酮植物鞣剂白及湿热稳定性

胶原与多酚的新反应研究成果（二）——鞣制与染色工艺中酚的反应

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北京皮革（中外皮革信息版）（中） 2008年第6期 79-84页

作者： A. D. covington[英国] c.s.evans[英国] T. H.Lilley[英国] 王康建(编译) 不详四川大学生物质与皮革工程系成都610065

多酚是原料皮与毛发色素的基本组成部分，它们能够聚合而产生自然黑、棕色与橘红色色素。漆酶能催化这种反应，不仅产生颜色，而且在胶原存在下，所产生的色素能以共价键的形式与革结合，革因而与一种耐晒色素牢固结合。还未证明可将革... 详细信息

多酚是原料皮与毛发色素的基本组成部分，它们能够聚合而产生自然黑、棕色与橘红色色素。漆酶能催化这种反应，不仅产生颜色，而且在胶原存在下，所产生的色素能以共价键的形式与革结合，革因而与一种耐晒色素牢固结合。还未证明可将革染成纯黑色，但是将革染成土灰色、绿色，乃至棕色／黑色，都是很容易的。这种胶原的稳定机理似乎有一个特征，就是围绕三股螺旋产生一个多酚矩阵，它对革的加固具有额外的帮助。既然传统工艺的每一个步骤，特别是鞣制，都是显著地弱化胶原，这就是去除这种效应的最佳化学反应。

关键词：化学反应多酚胶原染色工艺研究成果鞣制红色色素组成部分

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联苯酚在染色中的应用

北京皮革（中外皮革信息版）（中） 2008年第7期 77-78页

作者： O.sUPARNO A.D.cOVINGTON c.s.evans 罗荣（译）刘白玲（译）陈华林（译）吕绪庸（校）不详中国科学院皮革化工材料工程技术研究中心成都610041 中国科学院研究生院北京100049 成都培根皮革科研所 610041

本文采用一种新方法替代常规染色法使皮革着色，是采用能产生天然皮的颜色即黑色素的化学过程。1，8-二羟基萘和其他二羟基萘能够被一种多酚氧化酶——漆酶所氧化，并聚合成染料。这种染料不仅能产生颜色，而且在有胶原存在时，还可与... 详细信息

本文采用一种新方法替代常规染色法使皮革着色，是采用能产生天然皮的颜色即黑色素的化学过程。1，8-二羟基萘和其他二羟基萘能够被一种多酚氧化酶——漆酶所氧化，并聚合成染料。这种染料不仅能产生颜色，而且在有胶原存在时，还可与胶原形成共价结合，从而具有鞣制效果。

关键词：染色法联苯酚多酚氧化酶应用二羟基萘合成染料化学过程黑色素

Palladium-catalyzed s_(N)2 glycosylation of phenols

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science china chemistry 2024年第4期67卷 1037-1038页

作者： Yu Zhu P.Andrew evans Department of chemistry Queen’s University90 Bader LaneKingstonK7L 3N6Canada Xiangya school of Pharmaceutical sciences Central South UniversityChangsha 410013China

Glycosides are essential structural motifs present in an array of important medicines,materials,and natural products[1].Nevertheless,the chemo-and stereoselective construction of the glycosidic linkage is a long-standing challenge because relatively minor variations in the glycosyl donor or acceptor’s structure can impact stereoselectivity,thus influencing the product's functional properties.

关键词： properties Palladium catalyzed

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convergence,scalarization and continuity of Minimal solutions in set Optimization

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Journal of the Operations Research society of china 2024年第3期12卷 773-793页

作者： Karuna c.s.Lalitha Department of Mathematics University of DelhiDelhiDelhi110007India Department of Mathematics University of Delhi South CampusNew DelhiDelhi110021India

The paper deals with the study of two different aspects of stability in the given space as well as the image space,where the solution concepts are based on a partial order relation on the family of bounded subsets of a real normed linear *** first aspect of stability deals with the topological set convergence of families of solution sets of perturbed problems in the image space and Painlevé–Kuratowski set convergence of solution sets of the perturbed problems in the given *** convergence in the given space is also established in terms of solution sets of scalarized perturbed *** second aspect of stability deals with semicontinuity of the solution set maps of parametric perturbed problems in both the spaces.

关键词： Topological convergence Painlevé-Kuratowski convergence Upper semicontinuity Lower semicontinuity stability scalarization

Geochemistry and depositional environment of fuchsite quartzites from sargur Group,western Dharwar craton,India

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Acta Geochimica 2024年第3期43卷 555-570页

作者： c.s.sindhuja G.Harshitha c.Manikyamba K.s.V.subramanyam csIR(council of scientific and Industrial Research)-National Geophysical Research Institute(NGRI) Uppal RoadHyderabad 500007India

Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar craton including the oldest(~3.3 Ga)sargur Group of western Dharwar *** present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation *** major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and *** geochemical com-positions are characterized by high siO_(2),Al_(2)O_(3),low MgO,caO,strongly enriched cr(1326–6899 ppm),Ba(1165–3653 ppm),sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(Ucc).The Ucc normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/sm)Ucc=0.33–0.95]compared to heavy REE[(Gd/Yb)_(Ucc)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered *** overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin *** comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by cr-richfluids released during high-grade metamorphism of associated ultramafic *** sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of cr-richfluids and the formation of fuchsite quartzite during or after the *** sug-gest a pre-existing stable crust prior to the sargur Group and the link between orogenic events and various mineral deposits in the Dharwar craton.

关键词： Dharwar craton Ghattihosahalli Fuchsite quartzite Provenance Depositional setting

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Early Phases of star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： N.c.Martinez s.Paron cONIcET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

star-forming processes strongly influence the IsM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the HcN/HNc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)N,N_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HMPOs),hot molecular cores(HMcs) and ultracompact H II *** found that the use of the HcN/HNc ratio as a universal thermometer in the IsM should be taken with care because the HcN optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the HcN spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)N,N_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HMPOs and *** molecular line widths of these four species increase from the IRDc to the HMc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation IsM:molecules IsM:clouds

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Enantioselective iridium-catalyzed allylic substitution with a Reformatsky reagent: direct construction of β-stereogenic homoallylic esters

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science china chemistry 2024年第11期67卷 3791-3797页

作者： Debasis Pal Kirana D.Veeranna Yuk Fai Wong P.Andrew evans Department of chemistry Queen's University Xiangya school of Pharmaceutical sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

Local MFs Matrix Decomposition Algorithms for Elliptic BVPs in Annuli

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 93-120页

作者： c.s.chen Andreas Karageorghis Min Lei school of Mathematics and Natural sciences University of Southern MississippiHattiesburgMS 39406USA Department of Mathematics and statistics University of CyprusP.O.Box 20537Nicosia 1678Cyprus college of Mathematics Taiyuan University of TechnologyTaiyuan 030024P.R.China

We apply the local method of fundamental solutions(LMFs)to boundary value problems(BVPs)for the Laplace and homogeneous biharmonic equations in *** appropriately choosing the collocation points,the LMFs discretization yields sparse block circulant system *** a result,matrix decomposition algorithms(MDAs)and fast Fourier transforms(FFTs)can be used for the solution of the systems resulting in considerable savings in both computational time and storage *** accuracy of the method and its ability to solve large scale problems are demonstrated by applying it to several numerical experiments.

关键词： Local method of fundamental solutions Poisson equation biharmonic equation matrix decomposition algorithms fast Fourier transforms